Effect of defect-healing treatment on layered silicate precursors toward well-defined crosslinked frameworks

The synthesis of zeolites from two-dimensional layered precursors through interlayer crosslinking of the layers is a promising avenue for realizing meticulously designed synthesis routes. However, the presence of defective silanol species in the precursors hinders the achievement of desirable synthesis outcomes. This study focuses on PREFER-a layered precursor for FER-type zeolites-which was synthesized and subjected to a liquid-mediated defect-healing treatment that we recently developed. The defect-healing process involves the use of fluoride compounds for reconstruction and organic pore fillers to stabilize the framework. The effects of the treatment on the structure, composition, and iron insertion behavior of PREFER were examined. Characterization results revealed a reduction in the number of intralayer silanol defects, whereas interlayer silanols were unaffected by the defect-healing treatment. Furthermore, the subsequent alterations observed in the crosslinking behavior with iron atoms indicated that the defect-healing treatment may enhance the insertion of iron species between the layers in more homogeneous environments compared with the untreated precursor. These findings provide valuable insights into the prospects of controlled interlayer linkage in two-dimensional zeolite materials.

Synthesis and Structural Analysis of High-Silica ERI Zeolite with Spatially-Biased Al Distribution as a Promising NH3-SCR Catalyst

Erionite (ERI) zeolite has recently attracted considerable attention for its application prospect in the selective catalytic reduction of NOx with NH3 (NH3-SCR), provided that the high-silica (Si/Al > 5.5) analog with improved hydrothermal stability can be facilely synthesized. In this work, ERI zeolites with different Si/Al ratios (4.6, 6.4, and 9.1) are synthesized through an ultrafast route, and in particular, a high-silica ERI zeolite with a Si/Al ratio of 9.1 is obtained by using faujasite (FAU) as a starting material. The solid-state 29Si MAS NMR spectroscopic study in combination with a computational simulation allows for figuring out the atomic configurations of the Al species in the three ERI zeolites. It is revealed that the ERI zeolite with the highest Si/Al ratio (ERI-9.1, where the number indicates the Si/Al ratio) exhibits a biased Al occupancy at T1 site, which is possibly due to the presence of a higher fraction of the residual potassium cations in the can cages. In contrast, the Al siting in ERI-4.6 and ERI-6.4 proves to be relatively random.

Revealing the evolution of local structures in the formation process of alkaline earth metal cation-containing zeolites from glasses

Alkaline earth metal cations are ubiquitously present in natural zeolites but less exploited in synthetic zeolites due to their low solubility in water, and hence it remains elusive how they contribute to zeolite formation. Herein, harmotome, a PHI-type zeolite with Ba2+, is readily synthesized from a Ba-containing aluminosilicate glass. This glass-to-zeolite transformation process, in particular the structure-regulating role of Ba2+, is investigated by anomalous X-ray scattering and high-energy X-ray total scattering techniques. The results demonstrate that the steady Ba2+-aluminosilicate interactions not only help prevent the precipitation of barium species under alkaline synthetic conditions, but also dictate the local structures with distinct interatomic distances between the Ba2+ and the surrounding aluminosilicate species throughout the transformation process, which lead to the successful formation of harmotome without detectable impurities. This study highlights the usefulness of the comprehensive X-ray scattering techniques in revealing the formation scheme of the zeolites containing specific metal species. In addition, a promising alternative approach to design and synthesize zeolites with unique compositions and topologies by using well-crafted glasses with suitable metal cation dopants is demonstrated.

Unexpected Low Temperature Activity with Low N2 O Emission of Stabilized Al-rich Zeolite Beta for Selective Catalytic Reduction of NOx

The low temperature activity of Fe-loaded zeolites as selective catalytic reduction of NOx by NH3 (NH3 -SCR) catalysts is a critical drawback for practical application. Here, we found unexpected improvement of low temperature activity by our proposed post-synthetic treatment. An Al-rich zeolite beta (Si/Al=5) is employed as the catalyst support, and the parent sample is dealuminated for higher hydrothermal stability, followed by the liquid-mediated stabilization treatment and impregnation. It is found that stabilized samples feature excellent low temperature activity and high N2 selectivity even for a long-term operation, along with the ability to maintain high NOx conversion after aging. The improved SCR activity should be attributed to abundant acid sites in Al-rich framework and better stabilization of monomeric iron species after the stabilization treatment. Furthermore, the low yield of side product N2 O is probably due to the absence of the generation of NH4 NO3 during NH3 -SCR catalyzed by Fe-loaded zeolites.

Drastic Photoemission Color Alternation from a Single Molecule as a Starting Material Introduced in Acid-Treated Zeolites: From Pure Blue to White

Since high-purity blue- and white-light emitters are an indispensable group of materials for the creation of next-generation optical devices, a number of light-emitting materials have been developed from both inorganic and organic synthetic chemistry. However, these synthetic chemical methods are far from the perspective of green chemistry due to the multistep synthetic process and the use of toxic reagents and elements. Herein, we demonstrate that the introduction of simple unsubstituted anthracenes into zeolite-like pores can create a wide variety of luminescent materials, from ultrapure blue luminescent materials (emission peak at 465 nm with a full width of half-maximum of 8.57 nm) to efficient white luminescent materials [CIE coordination at (0.31, 0.33) with a quantum efficiency of 11.0% under 350 nm excitation light]. The method for rational design of the luminescent materials consists of the following two key strategies: one is molecular orbital confinement of the anthracene molecules in the zeolite nanocavity for regulating the molecular coordination associated with photoexcitation and emission and the other is the interaction of unsubstituted anthracenes with extra-framework aluminum species to stabilize the 2-dehydride anthracene cation in the zeolite cavity.

Atom-Selective Analyses Reveal the Structure-Directing Effect of Cs Cation on the Synthesis of Zeolites

To understand the crystallization mechanism of zeolites, it is important to clarify the detailed role of the structure-directing agent, which is essential for the crystallization of zeolite, interacting with an amorphous aluminosilicate matrix. In this study, to reveal the structure-directing effect, the evolution of the aluminosilicate precursor which causes the nucleation of zeolite is analyzed by the comprehensive approach including atom-selective methods. The results of total and atom-selective pair distribution function analyses and X-ray absorption spectroscopy indicate that a crystalline-like coordination environment gradually forms around Cs cations. This corresponds to the fact that Cs is located at the center of the d8r units in the RHO structure whose unit is unique in this zeolite, and a similar tendency is also confirmed in the ANA system. The results collectively support the conventional hypothesis that the formation of the crystalline-like structure before the apparent nucleation of the zeolite.

Tracking Sub-Nano-Scale Structural Evolution in Zeolite Synthesis by In Situ High-Energy X-ray Total Scattering Measurement with Pair Distribution Function Analysis

The crystallization mechanism of zeolites remains unclarified to date because of lack of effective techniques in characterizing the local structures of amorphous precursors under synthetic conditions. Herein, in situ high-energy X-ray total scattering measurement with pair distribution function analysis is performed throughout the hydrothermal synthesis of SSZ-13 zeolite to investigate the amorphous-to-crystalline transformation at the sub-nano level in real time. Ordered four-membered rings (4Rs) are dominantly formed during the induction period, prior to the significant increase in the number of symmetric six- and eight-membered rings (6Rs and 8Rs) in the crystal growth stage. These preformed ordered 4Rs contribute to the formation of d6r and cha composite building units containing 6Rs and 8Rs with the assistance of the organic structure-directing agent, leading to the construction of embryonic zeolite crystallites, which facilitate the crystal growth through a particle attachment pathway. This work enriches the toolbox for better understanding the crystallization pathway of zeolites.

Atezolizumab plus bevacizumab versus lenvatinib or sorafenib in non-viral unresectable hepatocellular carcinoma: an international propensity score matching analysis

BACKGROUND

A growing body of evidence suggests that non-viral hepatocellular carcinoma (HCC) might benefit less from immunotherapy.

MATERIALS AND METHODS

We carried out a retrospective analysis of prospectively collected data from consecutive patients with non-viral advanced HCC, treated with atezolizumab plus bevacizumab, lenvatinib, or sorafenib, in 36 centers in 4 countries (Italy, Japan, Republic of Korea, and UK). The primary endpoint was overall survival (OS) with atezolizumab plus bevacizumab versus lenvatinib. Secondary endpoints were progression-free survival (PFS) with atezolizumab plus bevacizumab versus lenvatinib, and OS and PFS with atezolizumab plus bevacizumab versus sorafenib. For the primary and secondary endpoints, we carried out the analysis on the whole population first, and then we divided the cohort into two groups: non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH) population and non-NAFLD/NASH population.

RESULTS

One hundred and ninety patients received atezolizumab plus bevacizumab, 569 patients received lenvatinib, and 210 patients received sorafenib. In the whole population, multivariate analysis showed that treatment with lenvatinib was associated with a longer OS [hazard ratio (HR) 0.65; 95% confidence interval (CI) 0.44-0.95; P = 0.0268] and PFS (HR 0.67; 95% CI 0.51-0.86; P = 0.002) compared to atezolizumab plus bevacizumab. In the NAFLD/NASH population, multivariate analysis confirmed that lenvatinib treatment was associated with a longer OS (HR 0.46; 95% CI 0.26-0.84; P = 0.0110) and PFS (HR 0.55; 95% CI 0.38-0.82; P = 0.031) compared to atezolizumab plus bevacizumab. In the subgroup of non-NAFLD/NASH patients, no difference in OS or PFS was observed between patients treated with lenvatinib and those treated with atezolizumab plus bevacizumab. All these results were confirmed following propensity score matching analysis. By comparing patients receiving atezolizumab plus bevacizumab versus sorafenib, no statistically significant difference in survival was observed.

CONCLUSIONS

The present analysis conducted on a large number of advanced non-viral HCC patients showed for the first time that treatment with lenvatinib is associated with a significant survival benefit compared to atezolizumab plus bevacizumab, in particular in patients with NAFLD/NASH-related HCC.

Dealumination of small-pore zeolites through pore-opening migration process with the aid of pore-filler stabilization

Small-pore zeolites are gaining increasing attention owing to their superior catalytic performance. Despite being critical for the catalytic activity and lifetime, postsynthetic tuning of bulk Si/Al ratios of small-pore zeolites has not been achieved with well-preserved crystallinity because of the limited mass transfer of aluminum species through narrow micropores. Here, we demonstrate a postsynthetic approach to tune the composition of small-pore zeolites using a previously unexplored strategy named pore-opening migration process (POMP). Acid treatment assisted by stabilization of the zeolite framework by organic cations in pores is proven to be successful for the removal of Al species from zeolite via POMP. Furthermore, the dealuminated AFX zeolite is treated via defect healing, which yields superior hydrothermal stability against severe steam conditions. Our findings could facilitate industrial applications of small-pore zeolites via aluminum content control and defect healing and could elucidate the structural reconstruction and arrangement processes for inorganic microporous materials.

AB1335 BONE MARROW EDEMA SCORE IN HAND X-RAY FILM BY AI DEEP LEARNING ASSOCIATE WITH MRI BONE EDEMA IN RHEUMATOID ARTHRITIS

Background

Rapid radiographic progression (RRP) was reported to be one of clinical symptom in difficult to treat RA(D2T RA) (1). Eular recommendation for imaging showed BME is strong and independent prognostic factor for bone destruction(2). We reported bone marrow edema (BME) in MRI image was most associated with RRP compared with bone erosion, synovitis in Adalimumab add-on therapy in MTX-IR RA patients(3). To rescue RRP, early detection of BME is important although cost of MRI is expensive and hard to repeat.

Objectives

To investigate the score of BME in hand X ray film by deep learning between X ray film and MRI BME information can discriminate the differences between BME and non-BME images.

Methods

In this work, we use a neural network consisted of convolutional layers and fully connected layers to classify X-ray images (Figure 1) In this paper, the output is the socre of BME which ranges from 0 to1(threshold = 0.4). We also used an interpretation technique called the Grad-CAM for visual explanations. Hand MRI (1.5T) were used.

Figure 1.

The convolutional neural network design. A red block “Conv” means a convolutional block. It contains a 2D convolution layer, a leaky relu activation function, a maxpooling layer and a batch normalization layer. The numbers above each “Conv” block are (kernal size, kernal size, kernal number). A green block “FC” is a fully connection layer. The number above it is (neuron number). After the last Softmax layer, the output becomes the probability of BME which ranges from 0 to 1.

Results

Regarding data split, 104 images including 79 non-BME images and 25 BME images are used as a hold-out test set. The rest of the images (473 images) are used as training data and validation data. Five fold cross-validation is used for these 473images. For each fold, there are about 378 images including 297 non-BME images and 81 BME images in the training set. There are about 95 images including 74 non-BME images and 21 BME images in the validation set. In order to fully utilize every image and unify the distribution of the training set and the validation set, the ratio of non-BME and BME is controlled to be the same which is about 3.66:1. The five folds showed similar performance on the hold-out test set. AUC is the area under the ROC curve. As the result, AUC which indicates the general performance of this model, ranged from 0.88 to 0.91. The average precision was 63% and the average recall rate was 87%. In this experiment, the initialization seed will greatly influence the final result. For example, AUC can be reduced to 0.73 from 0.89 because of a different initialization seed. It perhaps results from the shortage of data, which can easily make the neural network drop into a local minimum.We also utilized Grad-cam to visualize the result. The result of Grad-cam shows the importance of each part to the final prediction(Figure 2).

Figure 2.

Result of Grad-cam. Numbers in the parenthesises are the possibilities of BME. The middle case is unexpected because red region is the surrounding of the hand. The left and right cases may indicate the evidence for prediction.

Conclusion

The preliminary result is much better than a random guess. According to this result, there should be a certain difference between BME and non-BME images. If it’s the characteristic of BME that domains this difference, our classification algorithm will be feasible for BME. Our future work is to justify the evidence of the predictions and improve performance.

References

[1]Nagy G et al. Eular definition of difficult- to - treat to rheumatoid arthritis. Ann Rheum Dis 2021;80:31-35

[2]Colebatch AN et al. Eular recommendation for the use of imaging of joints in the clinical management of rheumatoid arthritis. Ann Rheum Dis 2013;72: 804-814

[3]Katayama K et al. Bone marrow OEDEMA is more associated with rapid radiographic progression than in synovitis or bone erosion by using low field MRI in bio-naiive rheumatoid arthritis patients treated with adalimumab and methotrexate combination therapy. Ann Rheum Dis 2014, eular meeting SAT0100.

Disclosure of Interests

None declared

Exploring Hydrothermal Synthesis of SAPO-18 under High Hydrostatic Pressure

The effect of external hydrostatic pressure on the hydrothermal synthesis of the microporous silicoaluminophosphate SAPO-18 has been explored. The crystallization of the SAPO-18 phase is inhibited at 150 °C under high pressures (200 MPa) when using relatively diluted synthesis mixtures. On the contrary, the use of concentrated synthesis mixtures allowed SAPO-18 to be obtained in all the studied conditions. The obtained solids were characterized with XRD, SEM, ICP-AES, TG and ²⁷Al and ³¹P MAS NMR spectroscopy. The results highlight the importance of the external pressure effect on the hydrothermal synthesis of molecular sieves and its influence on the interaction between the organic molecule and the silicoaluminophosphate network.

Nonalcoholic steatohepatitis in hepatocarcinoma: new insights about its prognostic role in patients treated with lenvatinib

BACKGROUND

Hepatocellular carcinoma (HCC) treatment remains a big challenge in the field of oncology. The liver disease (viral or not viral) underlying HCC turned out to be crucial in determining the biologic behavior of the tumor, including its response to treatment. The aim of this analysis was to investigate the role of the etiology of the underlying liver disease in survival outcomes.

PATIENTS AND METHODS

We conducted a multicenter retrospective study on a large cohort of patients treated with lenvatinib as first-line therapy for advanced HCC from both Eastern and Western institutions. Univariate and multivariate analyses were performed.

RESULTS

Among the 1232 lenvatinib-treated HCC patients, 453 (36.8%) were hepatitis C virus positive, 268 hepatitis B virus positive (21.8%), 236 nonalcoholic steatohepatitis (NASH) correlate (19.2%) and 275 had other etiologies (22.3%). The median progression-free survival (mPFS) was 6.2 months [95% confidence interval (CI) 5.9-6.7 months] and the median overall survival (mOS) was 15.8 months (95% CI 14.9-17.2 months). In the univariate analysis for OS NASH-HCC was associated with longer mOS [22.2 versus 15.1 months; hazard ratio (HR) 0.69; 95% CI 0.56-0.85; P = 0.0006]. In the univariate analysis for PFS NASH-HCC was associated with longer mPFS (7.5 versus 6.5 months; HR 0.84; 95% CI 0.71-0.99; P = 0.0436). The multivariate analysis confirmed NASH-HCC (HR 0.64; 95% CI 0.48-0.86; P = 0.0028) as an independent prognostic factor for OS, along with albumin-bilirubin (ALBI) grade, extrahepatic spread, neutrophil-to-lymphocyte ratio, portal vein thrombosis, Eastern Cooperative Oncology Group (ECOG) performance status and alpha-fetoprotein. An interaction test was performed between sorafenib and lenvatinib cohorts and the results highlighted the positive predictive role of NASH in favor of the lenvatinib arm (P = 0.0047).

CONCLUSION

NASH has been identified as an independent prognostic factor in a large cohort of patients with advanced HCC treated with lenvatinib, thereby suggesting the role of the etiology in the selection of patients for tyrosine kinase treatment. If validated, this result could provide new insights useful to improve the management of these patients.

No more trial and error for zeolites

[Figure: see text].

Revealing scenarios of interzeolite conversion from FAU to AEI through the variation of starting materials

Interzeolite conversion, which refers to the synthesis of zeolites using a pre-made zeolite as the starting material, has enabled promising outcomes that could not be easily achieved by the conventional synthesis from a mixture of amorphous aluminum and silicon sources. Understanding the mechanism of interzeolite conversion is of particular interest to exploit this synthesis route for the preparation of tailor-made zeolites as well as the discovery of new structures. It has been assumed that the structural similarity between the starting zeolite and the target one is crucial to a successful interzeolite conversion. Nevertheless, an image as to how one type of zeolite evolves into another one remains unclear. In this work, a series of dealuminated FAU zeolites were created through acid leaching and employed as the starting zeolites in the synthesis of AEI zeolite under various conditions. This experimental design allowed us to create a comprehensive diagram of the interzeolite conversion from FAU to AEI as well as to figure out the key factors that enable this kinetically favourable crystallization pathway. Our results revealed different scenarios of the interzeolite conversion from FAU to AEI and pinpointed the importance of the structure of the starting FAU in determining the synthesis outcomes. A prior dealumination was proven effective to modify the structure of the initial FAU zeolite and consequently facilitate its conversion to the AEI zeolite. In addition, this strategy allowed us to directly transfer the knowledge obtained from the interzeolite conversion to a successful synthesis of the AEI zeolite from dealuminated amorphous aluminosilicate precursors. These results offer new insights to the design and fabrication of zeolites via the interzeolite conversion as well as to the understandings of the crystallization mechanisms.

P–139 The role of hormones and LH receptor expression of granulosa cells collected from large and small follicles in natural/minimal stimulation cycle IVF

Study question

Do different follicle sizes influence gonadotropins (LH, FSH) and sex steroid (estradiol) in follicular fluids and LH receptor expression (LHCGR) in cumulus oocyte complexes (COCs)?

Summary answer

It was found that differences in levels of FSH, estradiol values and LHCGR mRNA expression level in COCs between small and large follicles.

What is known already

The maturity rate in oocytes of small follicle is significantly lower compared to that of large follicles.

Study design, size, duration

After obtaining written consents from 78 infertile patients, we aspirated the large (>15 mm) and small (<5 mm) follicles, and collected follicular fluids at oocyte retrieval.

Participants/materials, setting, methods

We measured levels of LH, FSH and estradiol by enzyme immunoassay from large and small follicular fluids after oocytes retrievals. All collected oocytes were distinguished from large and small follicles, we confirmed the maturity of retrieved oocytes by the presence of first polar body. Then we extracted total RNA from granulosa cells and measured mRNA expression of LHCGR, encoding the human LH receptor, by quantitative real-time PCR. Each value was normalized to ACTB mRNA levels.

Main results and the role of chance

LH levels were nearly equal between small and large follicles (P = 0.8356). Whereas FSH and estradiol levels were significantly lower in small follicles (P < 0.0001). The expression levels of LHCGR mRNA were significantly lower in small follicles than in large follicles during natural cycles. The maturity rate in oocytes of small follicle was significantly lower compared to that of large follicles (96.0% vs. 21.7%, P < 0001).

Limitations, reasons for caution

The main limitation of the present study was collected by 42 natural cycles and 36 mild stimulation cycles with letrozole following low-dose clomiphene.

Wider implications of the findings: In spite of almost the same LH levels between two groups, the reason why the significantly lower maturation rates of oocytes collected from small follicles is poor LHCGR mRNA expression due to insufficient granulosa cells glowth because of low FSH and estradiol levels.

Trial registration number

Not applicable

Reaction Kinetics Regulated Formation of Short-Range Order in an Amorphous Matrix during Zeolite Crystallization

The crystallization of zeolites, a disorder-to-order transformation of aluminosilicates, has not been thoroughly understood because the nucleation events in the amorphous matrix are difficult to recognize from the diverse structural changes, especially for the dense hydrogel systems. Therefore, relationships between the synthesis conditions, the generated amorphous species, and the crystallization behavior of zeolites remain unclear. Herein, by comparatively investigating the structural evolution of the aluminosilicate matrix in a dense hydrogel system when different Si reactants (fumed silica and silicate solution) are employed, we demonstrate that the reactivity of the reactants and the kinetics of the condensation reaction is critical to the formation of short-range order in an amorphous matrix, which greatly influences the nucleation frequency of zeolites. It was revealed that an amorphous solid containing plentiful Al-rich four-membered rings and Si-rich six-membered rings could be produced when fumed silica gradually reacted with sodium aluminate solution at 80 °C. It is considered that the interaction between these rings promotes the construction of the essential building units of zeolite X (FAU). In contrast, a complex aluminosilicate matrix was formed immediately when sodium silicate solution was mixed with sodium aluminate solution due to the intense condensation reaction. Furthermore, this complex matrix became more stable when the reactant mixture was hydrothermally treated at 80 °C, which significantly impedes the crystallization process. Aging the reactant mixture at ambient temperature before heating, instead, facilitated the formation of short-range order in the amorphous matrix, which increases the nucleation frequency of zeolites.

Tracking the crystallization behavior of high-silica FAU during AEI-type zeolite synthesis using acid treated FAU-type zeolite

During AEI zeolite synthesis using acid treated FAU (AcT-FAU), we found the recrystallization of high-silica FAU with high crystallinity and Si/Al ratio of 6.1 using N,N-dimethyl-3,5-dimethylpiperidinium hydroxide (DMDMPOH) after 2 h, followed by the crystallization of AEI via FAU-to-AEI interzeolite conversion at a longer synthesis time. In order to understand the formation mechanism of high-silica FAU and generalize its direct synthesis, we have investigated this synthesis process. An analysis of the short-range structure of AcT-FAU revealed that it has an ordered aluminosilicate structure having a large fraction of 4-rings despite its low crystallinity. The changes in the composition of the products obtained at different synthesis times suggested that DMDMP⁺ plays a certain role in the stabilization of the FAU zeolite framework. Moreover, the results of thermogravimetric analysis showed that the thermal stability of DMDMP⁺ changed with the zeolite conversion. To the best of our knowledge, this is the first study to clarify the structure-directing effect of DMDMP⁺ on FAU zeolite formation.

A high-silica FAU was obtained during FAU-to-AEI interzeolite conversion using acid treated FAU.

Recent progress in the improvement of hydrothermal stability of zeolites

Zeolites have been successfully employed in many catalytic reactions of industrial relevance. The severe conditions required in some processes, where high temperatures are frequently combined with the presence of steam, highlight the need of considering the evolution of the catalyst structure during the reaction. This review attempts to summarize the recently developed strategies to improve the hydrothermal framework stability of zeolites.

Synthetic and natural MOR zeolites as high-capacity adsorbents for the removal of nitrous oxide

N₂O is typically present as a trace gas in chemical processes, but its emission causes serious environmental issues. We herein demonstrate that ion-exchanged mordenite zeolites (framework code: MOR) can exhibit high capacities for N₂O adsorption under ambient conditions. In particular, a natural MOR zeolite gives an adsorption capacity as high as 0.34 mmol-N₂O per g-zeolite (1 atm, 25 °C), representing the best performing material among all zeolite-based adsorbents reported so far. The results contribute toward a comprehensive understanding of the structure-activity relationship and offer insights to establishing a zeolite-based adsorption system for enriching or removing N₂O.

Aryl radical initiators accumulated within layered silicates realize polystyrene with directly and regioselectively bonded aryl-terminal groups

The arbitrary design of a terminal group of polymers exploits the still-veiled functions of polymers with potential for application in fields such as drug delivery systems, photonics, and energy conversions. Here we demonstrate for the first time that polystyrenes with directly and regioselectively bonded aryl-terminal groups can be obtained via styrene radical polymerization initialized by arbitrary aryl radicals accumulated within the interlayer space of smectite clay minerals, which can be prepared by our developed 'Clay Catalysed ab intra Deamination (CCD)' method.

Ultrafast and continuous-flow synthesis of AFX zeolite via interzeolite conversion of FAU zeolite

Continuous-flow synthesis of AFX zeolite is achieved with the residence time of 10 min, using FAU zeolite as the silica and alumina source, and acid-leached seeds which promote secondary nucleation of AFX.

Rational Manipulation of Stacking Arrangements in Three-Dimensional Zeolites Built from Two-Dimensional Zeolitic Nanosheets

Unit-cell-thin zeolitic nanosheets have emerged as fascinating materials for catalysis and separation. The controllability of nanosheet stacking is extremely challenging in the chemistry of two-dimensional zeolitic materials. To date, the organization of zeolitic nanosheets in hydrothermal synthesis has been limited by the lack of tunable control over the guest-host interactions between organic structure-directing agents (OSDAs) and zeolitic nanosheets. A direct synthetic methodology is reported that enables systematic manipulation of the aluminosilicate MWW-type nanosheet stacking. Variable control of guest-host interactions is rationally achieved by synergistically altering the charge density of OSDAs and synthetic silica-to-alumina composition. These finely controlled interactions allow successful preparation of a series of three-dimensional (3D) zeolites, with MWW-layer stacking in wide ranges from variably disorder to fully ordered, leading to tunable catalytic activity in the cracking reaction. These results highlight unprecedented opportunities to modulate zeolitic nanosheets arrangement in 3D zeolites whose structure can be tailored for catalysis and separation.

Toward Efficient Synthesis of Chiral Zeolites: A Rational Strategy for Fluoride-Free Synthesis of STW-Type Zeolite

The STW-type zeolite is attractive for developing novel enantioselective syntheses/separation of chiral compounds because it is the only chiral zeolitic microporous material whose enantioenriched synthesis has been achieved. In addition to the conventional industries in which zeolites are used, STW should have diverse industrial applications in the pharmaceutical and food industries. However, the toxic and caustic fluoride required for synthesizing STW severely hinders its commercialization by mass production. Herein, we report the first example of fluoride-free STW synthesis, in which the two roles of fluoride-formation of a zeolitic framework rich in tetravalent T-atoms and promotion of double 4-membered ring unit formation-were substituted by dry gel conversion and Ge addition, respectively. The STW obtained was highly crystalline, with a similar micropore volume and thermal stability as those of original fluoride-based STW. Our approach is promising not only for the fluoride-free synthesis of enantiomeric STW but also for general fluoride-free syntheses.

Ultrafast Encapsulation of Metal Nanoclusters into MFI Zeolite in the Course of Its Crystallization: Catalytic Application for Propane Dehydrogenation

Encapsulating metal nanoclusters into zeolites combines the superior catalytic activity of the nanoclusters with high stability and unique shape selectivity of the crystalline microporous materials. The preparation of such bifunctional catalysts, however, is often restricted by the mismatching in time scale between the fast formation of nanoclusters and the slow crystallization of zeolites. We herein demonstrate a novel strategy to overcome the mismatching issue, in which the crystallization of zeolites is expedited so as to synchronize it with the rapid formation of nanoclusters. The concept was demonstrated by confining Pt and Sn nanoclusters into a ZSM-5 (MFI) zeolite in the course of its crystallization, leading to an ultrafast, in situ encapsulation within just 5 min. The Pt/Sn-ZSM-5 exhibited exceptional activity and selectivity with stability in the dehydrogenation of propane to propene. This method of ultrafast encapsulation opens up a new avenue for designing and synthesizing composite zeolitic materials with structural and compositional complexity.

Multi-objective de novo molecular design of organic structure-directing agents for zeolites using nature-inspired ant colony optimization

Organic structure-directing agents (OSDAs) are often employed for synthesis of zeolites with desired frameworks. A priori prediction of such OSDAs has mainly relied on the interaction energies between OSDAs and zeolite frameworks, without cost considerations. For practical purposes, the cost of OSDAs becomes a critical issue. Therefore, the development of a computational de novo prediction methodology that can speed up the trial-and-error cycle in the search for less expensive OSDAs is desired. This study utilized a nature-inspired ant colony optimization method to predict physicochemically and/or economically preferable OSDAs, while also taking molecular similarity and heuristics of zeolite synthesis into consideration. The prediction results included experimentally known OSDAs, candidates having structures closely related to known OSDAs, and novel ones, suggesting the applicability of this approach.

Inspired by the exploratory methods of ant colonies, adaptive optimization was employed to explore the chemical space for organic molecules that guide zeolite crystallization, giving both physicochemically and economically promising molecules.

Superior Ion-exchange Property of Amorphous Aluminosilicates Prepared by a Co-precipitation Method

The development of inexpensive inorganic ion-exchangers for the purification of environmental pollutants is a social demand. Amorphous aluminosilicates with a relatively high homogeneous Al environment are prepared by a feasible co-precipitation method, i. e., mixing an acidic aluminum sulfate solution and basic sodium silicate solution, which exhibit excellent ion-exchange selectivity for Cs⁺ and Sr²⁺ . The K_d value for Sr²⁺ was comparable with that of zeolite 4A. The local structures and ion-exchange behavior of the amorphous aluminosilicates are systematically investigated. The ion-exchange property of the amorphous aluminosilicates can be tuned by changing the interaction between the exchangeable cation and the amorphous aluminosilicates. Also, the amorphous aluminosilicates can adsorb bulky cations that zeolites hardly adsorb due to the limitation of the miropore size of zeolites.

SAT0146 INHIBITION OF RADIOGRAPHIC PROGRESSION BY IGURATINOD IN 116 JAPANESE RHEUMATOID ARTHIRITIS PATIENTS DESPITE CONVENTIONAL SYNTHETIC DISEASE-MODIFYING ANTIRHEUMATIC DRUGS THERAPY

Background:

Japanese double-blind clinical practice studies of Iguratimod (IGU) for active rheumatoid arthritis (RA) patients indicated an early and sustained efficacy as a new conventional synthetic disease-modyfing anti-rheumatic drugs (csDMARDs) [1] as well as the safety of the treatment[2]. IGU also inhibit activation of NFkB and production of RANKL, indicating strong inhibiting activity against bone destruction. However, studies focused on the inhibitory effects of joint destruction by IGU has been poorly documented in clinical practice (3).

Objectives:

To evaluate inhibitory effect during 1 year by additional IGU therapy in 116 RA patients despite csDMARDs therapy.

Methods:

Inhibitory effects of joint damage were evaluated by modified total Sharp scoring (mTSS) at baseline and 1 year after IGU prescription. RA activity was measured by DAS28-ESR.

Results:

The subjects were 116 cases, 30 male, age 63.2 yrs, disease duration 93.7 months. MTX was used weekly (84 cases, 72.4%), and cs DMARDs were used as BUC 43 cases, SASP 13 cases, TAC 5 cases, and LEF 1 cases. bDMARDs were used even in 8 cases, and steroids were used in 3.9 mg (70 cases, 60.3 %). Complications were observed in 70 cases (60.3%). DAS28-ESR were significantly improved from 4.29 (baseline) to 3.65 (6 months), 3.68 (12 months), respectively (P<0.0001). As shown in Figure 1, joint destruction measured by mTSS was significantly suppressed from 7.74 to 0.57 at 1 year (P<0.0001). 70.6% of patients satisfied structural remission (ΔmTSS≤0.5). Clinically relevant radiographic progression (CRRP)(mTSS>3) was observed in 10 cases (8.6%), and rapid radiographic progression(RRP) (mTSS≥5) was observed in 2 cases (1.6%). Adverse events were observed in 26 cases (22.4 %).

To investigate prognostic factor for CRRP, clinical data in baseline, 6, 12 months between ten patients with CRRP and 82 patients with structural remission were compared. As shown in Table 1, longer disease duration, more SJC (P<0.05), High CRP level(P<0.005) were prognostic for CRRP in IGU treated patients.

Conclusion:

Iguratimod suppressed not only clinical activities but also joint destruction in RA patients resistant to csDMARDs therapy.

Table 1. Prognostic factor for CRRP

References:

[1]Ishiguro N, Yamamoto K, Katayama K et al. Concomitant iguratimod therapy in patients with active rheumatoid arthritis despite stable doses of methotrexate a randomized, double-blind, placebo-controlled trial. Mod Rheumatol. 2013;23(3):430-9

[2]Hara M, Ishiguro N, Katayama K et al. Safety and efficacy of combination therapy of iguratimod with methotrexate for patients with active rheumatoid arthritis with an inadequate response to methotrexate: an open-level extension of a randomized, double-blind, placebo-controlled trial. Mod Rheumatol. 2014;24(3):410–8.

[3]Ishikawa K, Ishikawa J.Iguratimod, a synthetic disease modifying anti-rheumatic drug inhibiting the activation of NF-jB and production of RANKL: Its efficacy, radiographic changes,safety and predictors over two years’ treatment for Japanese rheumatoid arthritis patients. Mod.Rheumatol.2019,29(3), 418–429.

Disclosure of Interests:

None declared

FRI0127 Suppression of radiographic progression after gradual methotrexate tapering in patients with rheumatoid arthritis patients maintaining low disease activity - Prospective multicenter study-

Background:

Many studies have been reported to reduce/discontinue Biologics in the treatment of rheumatoid arthritis (RA). In contrast, study for tapering methotrexate (MTX) has been limited (1,2).

Objectives:

We prospectively examined whether bone destruction will progress at 48 weeks after tapering or discontinuing MTX (UMIN000028875).

Methods:

The subjects were RA patients who have maintained low disease activity or lower for 24 weeks or more in DAS28-CRP after MTX administration. Patients having PDUS Grade 2 or 3 per site by bilateral hand ultrasonography (26 area) were excluded in this study owing to risk for joint destruction. The joint destruction was evaluated by the joint X-ray evaluation by modified total Sharp scoring (mTSS) at 1 year after the start of tapering MTX. Evaluation of clinical disease activities, severe adverse events, the continuation rate during MTX tapering were also evaluated. According to tapering response, prognostic factor for good response for tapering, joint destruction was determined. Predictors for successful tapering MTX and progression of bone destruction were determined. Statistical analysis was performed by t-test or Wilcoxon rank sum test using SAS .13.2 software.

Results:

The subjects were 79 (16 males, 63 females). Age average 60.9 years, disease duration 4 years 4 months, MTX dose 8.43 mg / w, DAS28-CRP 1.52, DMARDs (24.3%), ACPA 192.7 U / ml (70.5%), RF 55.6 IU / ml (65.4%).MTX was tapered from an average of 8.43 mg / w before study to 5.46 mg / w one year later. In the treatment evaluation, DAS28-CRP increased from 1.52 to 1.84. 89.7% of subjects did not progress joint damage. Other disease activities significantly increased (Table 1). The one-year continuation rate was 78.2%. Since tapering effects were varied widely, we divided patients into three groups; Flared group (N=14, initial MTX dose 8.71mg/w, final MTX dose 8.42mg/w), Low response group (N=31, final MTX reduction rate< 50%, initial MTX dose 8.93mg/w, final MTX dose 6.22mg/w), High response group (N=34, final MTX reduction rate≥ 50%, initial MTX dose 8.5mg/w, final MTX dose 3.15mg/w)(Table 2).Higher RF value at baseline and higher MTX dose at 3M, 6M were predictors of whether a subject was in Low response group or High Response group. Higher RF value and mTSS at baseline and higher MTX dose at 6M were predictors whether a subject was in Flared group or High response group. Lower age was predictor of whether a subject was in Flared group or Low responder group. Finally, mean ΔmTSS /y in Flared group (0.36) was not significantly higher than in low response group (0.07) and in high response group (0.01).

Table 1Table 2.

Predictors for successful tapering MTX and progression of bone destruction

Conclusion:

Patients with MTX-administered low disease activity and finger joint echo PDUS grade 1 satisfy almost no joint destruction even after MTX reduction. For tapering, predictors may be helpful for maintaining patient’s satisfaction.

References:

[1]Baker KF, Skelton AJ, Lendrem DW et al. Predicting drug-free remission in rheumatoid arthritis: A prospective interventional cohort study. J. Autoimmunity. 2019;105: 102298.

[2]Lillegraven S, Sundlisater N, Aga A et al. Tapering of Conventional Synthetic Disease Modifying Anti-Rheumatic Drugs in Rheumatoid Arthritis Patients in Sustained Remission: Results from a Randomized Controlled Trial. American College of Rheumatology. 2019; Abstract L08.

Disclosure of Interests:

None declared

AB0298 LONG-TERM SUPPRESSION OF RAPID RADIOGRAPHIC PROGRESSION AFTER DISCONTINUATION/REDUCTION OF SHORT-TERM BIOLOGIC THERAPY IN PATIENTS WITH EARLY DESTRUCTIVE RHEUMATOID ARTHRITIS ACCOMPANIED WITH EXTENSIVE BONE MARROW EDEMA

Background:

We reported that short-term (3 or 6 months) treatment with biologics (BIO) group compared with conventional synthetic non-biological disease-modifying anti rheumatic drug (csDMARDs) enhanced group is more effective in the reducing bone marrow edema (BE) and improving structural remission in early destructive RA accompanied with extensive hand BM despite csDMARDs therapy (1).

Objectives:

Purpose of this extended study is to investigate whether suppression of RRP will maintain after the discontinuation/reduction of short term biological treatment during over 1 year. Clinical registration number; (UMIN-CTR 000013614)(Figure 1)

Methods:

RA disease activity was evaluated by DAS28-ESR after BIO withdrawal/reduction at 12 months. Bone destruction was determined by modified total Sharp scoring (mTSS) using by conventional radiography expressed as yearly progression of mTSS (ΔmTSS/y) at 12 months. Statistical analysis were performed by t-test or Wilcoxon rank sum test using SAS .13.2 software

Results:

Fourteen out of 23 patients in BIO group achieved improvement of BM (>70% improvement of baseline BE). Three patient continued BIO. Among 11 patient started to discontinuation/reduction of BIO, 7 patients were successful for discontinuation of BIO. Four patients flared (Table 1). Mean DAS28-ESR, mean ΔmTSS/y at 0, 12 months after discontinuation in 7 patients were 1.77, 2.02 and -0.66,-0.44, respectively (no significant difference between values in 0 and12 month). In contrast, those in 4 flared patients were 1.91, 4.08 and 0, 1.83, respectively (significant difference). Finally, to resolve baseline prognostic factors for improvement of BE for biological treatment, we compared baseline data between 14 BE improved and 9 BE unimproved RA patients. Low DAS28-ESR at 3 or 6 month (P<0.001) are indicated for significant prognostic factor for improvement of BE, although Low DAS28-ESR at baseline (P=0.07) may associate improvement of BE.

Table 1.

Summary of 1 year clinical data in 11 patients treated in BIO discontinuation/reduction after improvement of BE by short-term treatment of BIO

Conclusion:

Results of this study indicated suppression of RRP will maintain during over 1 year after the discontinuation of short term biological treatment in some patients. We recommend that a short-term treatment with biologics for early RA patients, who are resistant to non-bio DMARDs therapy and at high risk to transit to RRP, will be an effective and economical treatment strategy.

References:

[1]K. Katayama, T. Okubo, S. Sato et al. Prevention of extensive bone marrow edema and consequent rapid radiographic progression by short term usage of biologics in DMARDs resistant patients with early destructive rheumatoid arthritis. EULAR meeting. FRI 0124(2018).

Disclosure of Interests:

None declared

Extremely Stable Zeolites Developed via Designed Liquid-Mediated Treatment

Improving the stability of porous materials for practical applications is highly challenging. Aluminosilicate zeolites are utilized for adsorptive and catalytic applications, wherein they are sometimes exposed to high-temperature steaming conditions (∼1000 °C). As the degradation of high-silica zeolites originates from the defect sites in their frameworks, feasible defect-healing methods are highly demanded. Herein, we propose a method for healing defects to create extremely stable high-silica zeolites. High-silica (SiO₂/Al₂O₃ > 240) zeolites with *BEA-, MFI-, and MOR-type topologies could be stabilized by significantly reducing the number of defect sites via a liquid-mediated treatment without using additional silylating agents. Upon exposure to extremely high temperature (900-1150 °C) steam, the stabilized zeolites retain their crystallinity and micropore volume, whereas the parent commercial zeolites degrade completely. The proposed self-defect-healing method provides new insights into the migration of species through porous bodies and significantly advances the practical applicability of zeolites in severe environments.

Water-Dispersible Triplet-Triplet Annihilation Photon Upconversion Particle: Molecules Integrated in Hydrophobized Two-Dimensional Interlayer Space of Montmorillonite and Their Application for Photocatalysis in the Aqueous Phase

Green incident light (λ = ∼500 nm) is converted to blue light (λ = 400-450 nm) in air using bulky alkylammonium (DMDOA⁺), 9,10-diphenylanthracene (DPA), and Ru(dmb)₃²⁺ (dmb = 4,4'-dimethyl-2,2'-bipyridine) intercalated in a layered clay compound called "montmorillonite" [MMT-DMDOA⁺-DPA-Ru(dmb)₃²⁺]. The two-dimensional interstitial space has an interlayer spacing of a few nanometers. Emitter DPA is present in this interlayer spacing, having an intermolecular distance of approximately 3.0 nm at a high concentration. Sensitizer Ru(dmb)₃²⁺ is relatively dilute, having an intermolecular distance of 47 nm. The emission decay measurements and quantitative evaluation of the emission intensity demonstrate that blue light emission is induced by sequential processes, which consist of a triplet-triplet (T-T) energy transfer reaction from Ru(dmb)₃²⁺ to DPA and T-T annihilation of DPA molecules. From thermogravimetry and Fourier transform infrared spectra measurements, we observe that the cointercalated alkylammonium acts as a waterproof agent to prevent quenching of the molecules in the excited triplet states by H₂O. Finally, we demonstrate a photocatalytic decomposition of Rhodamine B dissolved in H₂O-containing MMT-DMDOA⁺-DPA-Ru(dmb)₃²⁺ and Pt-deposited WO₃ photocatalyst, where wavelength of incident light (λ > 440 nm) is longer than the absorption edge of WO₃ photocatalyst. The mechanism of photocatalytic decomposition is the following: (i) the incident long wavelength light is upconverted to 400-450 nm light by MMT-DMDOA⁺-DPA-Ru(dmb)₃²⁺, and then, (ii) WO₃ photocatalyst is excited by the generated 400-450 nm light, and finally, (iii) Rhodamine B is decomposed on the Pt cocatalyst induced by the holes in a valence band of WO₃.

Unique crystallization behavior in zeolite synthesis under external high pressures

Hydrothermal synthesis of zeolites under external high pressures generates unique crystallization behaviors that are different from the synthesis under autogenous pressure.

Optimized ultrafast flow synthesis of CON-type zeolite and improvement of its catalytic properties

The fast synthesis of CON-type zeolite could be an option for mass production using a continuous flow synthesis system.

Bridging the Gap between Structurally Distinct 2D Lamellar Zeolitic Precursors through a 3D Germanosilicate Intermediate

There is broad scientific interest in lamellar zeolitic materials for a large variety of technological applications. The traditional synthetic methods towards two-dimensional (2D) zeolitic precursors have made a great impact in the construction of families of related zeolites; however, the connection between structurally distinct 2D zeolitic precursors is much less investigated in comparison, thereby resulting in a synthetic obstacle that theoretically limits the types of zeolites that can be constructed from each layer. Herein, we report a Ge-recycling strategy for the topotactic conversion between different 2D zeolitic precursors through a three-dimensional (3D) germanosilicate. Specifically, the intermediate germanosilicate can be constructed within 150 min by taking advantage of its structural similarity with the parent lamellar precursor. This process enables the conversion of one 2D zeolite structure into another distinct structure, thus overcoming the synthetic obstacle between two families of zeolitic materials.

Bioinspired Approach to Silica Nanoparticle Synthesis Using Amine-Containing Block Copoly(vinyl ethers): Realizing Controlled Anisotropy

Core-shell polymer-silica hybrid nanoparticles smaller than 50 nm in diameter were formed in the presence of micelles of poly(2-aminoethyl vinyl ether-block-isobutyl vinyl ether) (poly(AEVE_m-b-IBVE_n)) through the hydrolysis and polycondensation of alkoxysilane in aqueous solution at a mild pH and temperature. The size of the nanoparticles as well as the number and size of the core parts were effectively controlled by varying the molecular weight of the copolymers. The polymers could be removed by calcination to give hollow silica nanoparticles with Brunauer-Emmett-Teller surface areas of more than 500 m² g^-1. Among these, silica nanoparticles formed with poly(AEVE₁₁₅-b-IBVE₄₀) displayed an anisotropy of single openings in the shell. The use of an alternative copolymer, poly(AEVE-b-2-naphthoxyethyl vinyl ether) (poly(AEVE₁₁₃-b-βNpOVE₄₀)), yielded core-shell nanoparticles with less pronounced anisotropy. These results showed that the degree of anisotropy could be controlled by the rigidity of micelles; the micelle of poly(AEVE₁₁₅-b-IBVE₄₀) was more deformable during silica deposition than that of poly(AEVE₁₁₃-b-βNpOVE₄₀) in which aromatic interactions were possible. This bioinspired, environmentally friendly approach will enable large-scale production of anisotropic silica nanomaterials, opening up applications in the field of nanomedicine, optical materials, and self-assembly.

Tracking the rearrangement of atomic configurations during the conversion of zeolite to zeolite

In order to realize designed synthesis, understanding the formation mechanism of zeolites at an atomic level has long been aspired, but remains challenging due to the fact that the knowledge of atomic configurations of the species formed during the process is limited. We focus on a synthesis system that crystallizes CHA zeolite from FAU zeolite as the sole source of tetrahedral atoms of Si and Al, so that end-to-end characterization can be conducted. Solid-state ²⁹Si MAS NMR is followed by high-throughput computational modeling to understand how atomic configurations changed during the interzeolite conversion. This reveals that the structural motif commonly found in FAU and CHA is not preserved during the conversion; rather, there is a specific rearrangement of silicates and aluminates within the motif. The atomic configuration of CHA seems to be influenced by that of the starting FAU, considering that CHA synthesized without using FAU results in a random Al distribution. A Metropolis Monte-Carlo simulation combined with a lattice minimization technique reveals that CHA derived from FAU has energetically favorable, biased atomic locations, which could be a result of the atomic configurations of the starting FAU. These results suggest that by choosing the appropriate reactant, Al placement could be designed to enhance the targeted properties of zeolites for catalysis and adsorption.

A series of magnon crystals appearing under ultrahigh magnetic fields in a kagomé antiferromagnet

Geometrical frustration and a high magnetic field are two key factors for realizing unconventional quantum states in magnetic materials. Specifically, conventional magnetic order can potentially be destroyed by competing interactions and may be replaced by an exotic state that is characterized in terms of quasiparticles called magnons, the density and chemical potential of which are controlled by the magnetic field. Here we show that a synthetic copper mineral, Cd-kapellasite, which comprises a kagomé lattice consisting of corner-sharing triangles of spin-1/2 Cu2+ ions, exhibits an unprecedented series of fractional magnetization plateaus in ultrahigh magnetic fields of up to 160 T. We propose that these quantum states can be interpreted as crystallizations of emergent magnons localized on the hexagon of the kagomé lattice.

Insights into the ion-exchange properties of Zn(ii)-incorporated MOR zeolites for the capture of multivalent cations

Understanding the properties of zeolites for cation exchange is important because the ion-exchange performance largely determines their suitability in applications such as catalysis and adsorptive separation. We synthesized a Zn(ii)-incorporated mordenite-framework aluminosilicate zeolite (Zn,Al-MOR), in which both Zn and Al are substituted in the framework, and studied its ion-exchange behavior for multivalent cations. For comparison, the original aluminosilicate mordenite (Al-MOR) was also synthesized with a composition adjusted to ensure that its charge density was similar to that of Zn,Al-MOR. While the incorporation of Zn(ii) led to a slower kinetic process, the selectivities and the exchange capacities toward multivalent cations (especially divalent cations) were significantly improved. Herein, we discussed the mechanism responsible for improving the ion-exchange performance in the presence of Zn(ii) and found that the incorporation of Zn(ii) led to a significant improvement in the ion-exchange temperature dependence of the MOR, which led to the ability to enhance ion-exchange capacity through temperature control during actual application. It was also revealed that the presence of Zn(ii) significantly improves selectivity and spontaneity toward the exchange of multivalent cations, Ni2+. Moreover, XRD and nitrogen-adsorption/desorption analyses revealed that the structures of the materials are maintained during the ion exchange, which is indicative of superior structural stability and tolerance to ion exchange.

Ultrafast synthesis of zeolites: breakthrough, progress and perspective

An ultrafast route was established to synthesize industrially important zeolites in several minutes, which represents a breakthrough in the field of zeolite synthesis.