Silicon microfabricated reactor for operando XAS/DRIFTS studies of heterogeneous catalytic reactions

A novel microreactor for operando XAS and DRIFTS studies of catalytic reactions is reported, exhibiting plug-flow, isothermal behaviour and absence of mass transfer resistances and dead volume, enabling time- and spatially-resolved experiments.

Facile room temperature deposition of gold nanoparticle-ionic liquid hybrid film on silica substrate

This work presents facile synthesis of gold nanoparticle (Au NP)-ionic liquid hybrid film of <10nm by a simple two-step process at room temperature by deposition of Au NPs suspended in 1-hexyl-1methyl-pyrolidinium bromide, on Si (111) substrates. FTIR results demonstrated that ionic liquid properties remain unaltered during and after Au NP synthesis, and even coating on Si (111) substrate. XRD, XPS, and XAS spectral data confirm the presence of Au(0) while EXAFS data indicated the presence of small particles or incomplete surface species. Cross-sectional analysis using FE-SEM and edge length measurement using AFM showed that the film thickness is ca 10nm.

Particle size, morphology and phase transitions in hydrothermally produced VO2(D)

An easy and reproducible method to synthesise thermochromic VO₂[M] via VO₂[D] at a low calcination temperature.

Length and Weight Relationship and Growth Performance of <i>Meretrix casta</i> under Experimental Culture Condition in Three Different Estuarine Environment

The Meretrixcasta is an edible clam for human beings and it is widely distributed around the aquatic ecosystem. The clam has relatively thick shells that can attain a length of three inches. The knowledge of the biology, culture and biochemical composition of any edible organism is extremely important. Though the size, shape and colour of clam are different their nutritive value is very good. A maximum average length of 27.15mm was observed in the M.casta studied during 2011 and a maximum average length of 26.51mm was observed during 2012. The average lengths of M.casta in all the three different estuaries studied were as follows: 27.15 > 25.82 > 25.04 mm in 2011 and 26.51 > 25.88 > 25.17mm in 2012. A maximum average weight of 7.824 and 7.155g was observed during 2011 and in 2012; a maximum weight of 7.528g and minimum of 6.941g was recorded uniformly in all the three different estuaries. However, in 2011and 2012 a maximum and minimum of average length of 26.86, 25.10 mm, and average weight of 7.67 and 7.05g respectively were noticed in both Vellar and Uppanar estuaries of M.casta. the present investigation, it is clearly observed that M.casta can grow a weight of 0.13g/day and length of 0.122mm/day among the three different estuaries studied in the Cuddalore district which is located in Bay of Bengal.

Determination of Ammonia, Nitrate and Nitrite Concentrations in Marine Water Samples with Cultured Marine Ornamental Fish Water Sample Analysis

The present studies were concentration of ammonia, nitrite, nitrate, dissolved oxygen, temperature, salinity and pH. For seven physicochemical parameters were determined in marine water samples along with marine ornamental fish water sources from CAS in marine biology laboratory conditions at Parangipettai. Water sample have been studied at a marine water sources. The study concentrations of parameters like ammonia, nitrite, nitrate, dissolved oxygen, temperature, salinity, and pH. And physicochemical parameters have been calculated. The data showed the difference of the investigated parameters in samples as follows; Concentration of water quality parameters like ammonia was maximum level above 1.158 μmol¯1, nitrite was ranging from 0.811 to 0.922 μmol¯1, nitrate was range maximum level above 4.84 μmol¯1, dissolved oxygen content was maximum level above 2.4 mg¯1, temperature was ranging from 32.3 to 100 °C, salinity values ranging from 0 to 36ppt and pH was ranging from 6.5 to 8.0. During the study period of from July 2013 to June 2014 we investigated concentration of seven physicochemical parameters value Marine water samples with cultured fish species in presence of water from CAS in Marine Biology laboratory Annamalai University at Parangipettai.

Determination of Ammonia, Nitrate and Nitrite Concentrations in Marine Water Samples with Cultured Marine Ornamental Fish Water Sample Analysis

The present studies were concentration of ammonia, nitrite, nitrate, dissolved oxygen, temperature, salinity and pH. For seven physicochemical parameters were determined in marine water samples along with marine ornamental fish water sources from CAS in marine biology laboratory conditions at Parangipettai. Water sample have been studied at a marine water sources. The study concentrations of parameters like ammonia, nitrite, nitrate, dissolved oxygen, temperature, salinity, and pH. And physicochemical parameters have been calculated. The data showed the difference of the investigated parameters in samples as follows; Concentration of water quality parameters like ammonia was maximum level above 1.158 μmol¯1, nitrite was ranging from 0.811 to 0.922 μmol¯1, nitrate was range maximum level above 4.84 μmol¯1, dissolved oxygen content was maximum level above 2.4 mg¯1, temperature was ranging from 32.3 to 100 °C, salinity values ranging from 0 to 36ppt and pH was ranging from 6.5 to 8.0. During the study period of from July 2013 to June 2014 we investigated concentration of seven physicochemical parameters value Marine water samples with cultured fish species in presence of water from CAS in Marine Biology laboratory Annamalai University at Parangipettai.

Proximate, Fatty Acid and Mineral Composition of Orange-Spotted Grouper <i>Epinephelus coioides </i>from Parangipettai Coast

The marine fish are extraordinarily nourishing food and are affluently accessible fish meat source. Fresh examined sample of grouper fish was collected from Mudasal odai fish landing center. The protein, carbohydrate, lipid, ash and moisture contents of Epinephelus coioides were found to be 19.07 mg, 4.03, 2.61, 77.38 mg and 1.21 mg/g respectively. The potassium and phosphorus are the predominant elements other nine components are present in considerable quantities in the total of 11 minerals. Palmitic acid, Oleic acid and Stearic acid were observed to be the major elements of total presented 15 fatty acids. In this current study we have concluded the grouper fish having rich source of protein and good fatty acids and it will facilitate to enhance the nutrition level on poor folks

Proximate, Fatty Acid and Mineral Composition of Orange-Spotted Grouper <i>Epinephelus coioides </i>from Parangipettai Coast

The marine fish are extraordinarily nourishing food and are affluently accessible fish meat source. Fresh examined sample of grouper fish was collected from Mudasal odai fish landing center. The protein, carbohydrate, lipid, ash and moisture contents of Epinephelus coioides were found to be 19.07 mg, 4.03, 2.61, 77.38 mg and 1.21 mg/g respectively. The potassium and phosphorus are the predominant elements other nine components are present in considerable quantities in the total of 11 minerals. Palmitic acid, Oleic acid and Stearic acid were observed to be the major elements of total presented 15 fatty acids. In this current study we have concluded the grouper fish having rich source of protein and good fatty acids and it will facilitate to enhance the nutrition level on poor folks

Bio-inspired CO2conversion by iron sulfide catalysts under sustainable conditions

CO₂conversion to small bio-molecules on greigite minerals under room temperature and pressure.

Recipes from Yellow Clam <i>Meretrix casta</i> (Chemnitz)

Seafood is an excellent provider of protein with high biological values. Fish, shellfish and other aquatic organisms are appropriate for food and have world-wide importance. They‟re wonderful sources of high quality proteins, superior to those in red meat and poultry foods. The human dietary amendments that characterize the “nutrition transition” include every quantitative and qualitative change in the human diets. The present study Meretrix casta meat is used for the preparation of excellent recipes like cake, soup and mint stuffed tomato with yellow clam using M. casta meat, that have the potential to be become a regular food item in the house hold diet with consumer acceptance. The differences in food habits over the length and breadth of the nation are most that available food resources are not being used properly due to the lack of information regarding their importance. The panel of judges vouched safe for taste and delicacy of the dishes in the present study. The panel detected that the dishes were a lot of as good as those created out of the much sought after seafood in taste, smell and flavor

Proximate Composition and Fatty Acid Analysis of Puffer Fish, <i>Lagocephalus inermis</i> (Temminck and Schlegel, 1850) and <i>Lagocephalus lunaris</i> (Bloch and Schneider, 1801) from Parangipettai, Southeast Coast of India

The nutritional effects of marine food have increased far and wide due to the beneficial effects of consuming marine food, fats and oils. In general, the proximate composition is well known as a proportion composition of basic elements such as protein, lipids, carbohydrate, minerals and water. The puffer fish Lagocephalus lunaris and Lagocephalus inermis were collected at Mudasal odai fish landing centre and the skin and visceral organs like gonads and intestines were removed the edible portion only took for the analysis. Species of the fish sample was oven-dried in an electric oven at between 70 – 80 °C until the samples had constant weight. The protein, carbohydrate, fat, ash and moisture content of green -rough-back puffer fish and smooth-backed blow fish were investigated. L. lunaris and L. inermis were has 9.22 %, 8.92 %, 1.96 %, 1.87 %, 11.25 %, 11.98 %, 80.32 %, 86.05 %, 0.96 %, 1.27 % respectively. Totally seven saturated fatty acids; ten Mono unsaturated fatty acids and two poly unsaturated fatty acids were found as the major components on the investigated puffer fish. Polyunsaturated fatty acid like n-3 has 31.17 %, 31.19 and n-6 7.26 %, 7.29 % of PUSFA found as the dominant composition on puffer fish. This study revealed that these species are having high saturated fatty acid and protein content and able to compete with more commercially utilize species in terms of nutritional value, and they can definitely also compete when it comes to taste. It can act as a good source of nutritional and economic value when it is carefully handled and properly cooked.

Proximate Composition and Fatty Acid Analysis of Puffer Fish, Lagocephalus inermis (Temminck and Schlegel, 1850) and Lagocephalus lunaris (Bloch and Schneider, 1801) from Parangipettai, Southeast Coast of India

The nutritional effects of marine food have increased far and wide due to the beneficial effects of consuming marine food, fats and oils. In general, the proximate composition is well known as a proportion composition of basic elements such as protein, lipids, carbohydrate, minerals and water. The puffer fish Lagocephalus lunaris and Lagocephalus inermis were collected at Mudasal odai fish landing centre and the skin and visceral organs like gonads and intestines were removed the edible portion only took for the analysis. Species of the fish sample was oven-dried in an electric oven at between 70 – 80 °C until the samples had constant weight. The protein, carbohydrate, fat, ash and moisture content of green -rough-back puffer fish and smooth-backed blow fish were investigated. L. lunaris and L. inermis were has 9.22 %, 8.92 %, 1.96 %, 1.87 %, 11.25 %, 11.98 %, 80.32 %, 86.05 %, 0.96 %, 1.27 % respectively. Totally seven saturated fatty acids; ten Mono unsaturated fatty acids and two poly unsaturated fatty acids were found as the major components on the investigated puffer fish. Polyunsaturated fatty acid like n-3 has 31.17 %, 31.19 and n-6 7.26 %, 7.29 % of PUSFA found as the dominant composition on puffer fish. This study revealed that these species are having high saturated fatty acid and protein content and able to compete with more commercially utilize species in terms of nutritional value, and they can definitely also compete when it comes to taste. It can act as a good source of nutritional and economic value when it is carefully handled and properly cooked.

Fatal necrotizing fasciitis following elective inguinal hernia repair

Necrotizing soft tissue infections (NSTIs) following elective hernia repair are extremely uncommon, though they can occur following emergency surgery for complicated hernias. They are also usually seen in individuals with impaired immunity. We report a case of fatal necrotizing fasciitis following elective hernia repair in an otherwise healthy young patient. A high index of suspicion is required to diagnose this condition early, as it is difficult to differentiate it from superficial surgical site infection.

Pelvic leiomyoma presenting as perineal hernia

Primary perineal hernias are rare and can be a diagnostic challenge. We report the case of a 45-year-old female patient who presented with painless perineal swelling suggestive of perineal hernia. Computed tomography (CT) scanning revealed a pelvic mass herniating through the pelvic floor into the perineum. The lesion was completely excised by an abdominoperineal approach. Histopathological examination of the lesion revealed a leiomyoma. This case report suggests that the possibility of perineal herniation of a pelvic leiomyoma should be considered in a female patient with suspected primary perineal hernia. We recommend an abdominoperineal approach for the surgical management of such a lesion.

The rheology of collapsing zeolites amorphized by temperature and pressure

Low-density zeolites collapse to the rigid amorphous state at temperatures that are well below the melting points of crystals of the same composition but of conventional density. Here we show, by using a range of experimental techniques, how the phenomenon of amorphization is time dependent, and how the dynamics of order-disorder transitions in zeolites under temperature and pressure are equivalent. As a result, thermobaric regions of instability can be charted, which are indicative of polyamorphism. Moreover, the boundaries of these zones depend on the rate at which temperature or pressure is ramped. By directly comparing the rheology of collapse with structural relaxation in equivalent melts, we conclude that zeolites amorphize like very strong liquids and, if compression occurs slowly, this is likely to lead to the synthesis of perfect glasses.

Solvent-free routes to clean technology

A major aim for the chemical technology of the future is the avoidance of noxious and environmentally unacceptable organic solvents. In this concept article we discuss more environmentally friendly and highly selective alternatives which we have evolved for carrying out a number of important chemical conversions. These entail the use of porous heterogeneous catalysts in which the active sites have been atomically engineered and fully characterized. Such solid catalysts operate under solvent-free conditions and usually entail one-step processes.

The role of synchrotron-based studies in the elucidation and design of active sites in titanium-silica epoxidation catalysts

X-ray absorption fine structure (XAFS) measurements unambiguously establish the structure of the active centers in high-performance Ti-SiO2 epoxidation catalysts. Subtleties in structural changes in proceeding from the dispersed titanocene dichloride precursor to the anchored Ti(IV) centers are charted, in situ, by both near-edge (XANES) and extended-edge (EXAFS) measurements. The active centers are tripodally attached titanol groups: (Si-O)3-TiOH. These permit facile expansion of the coordination shell (also monitored by in situ XAFS studies) during catalysis, and thereby lead to the formulation of a plausible mechanism of epoxidation of alkenes that is consonant with recent DFT computations. Previously proposed mechanisms, based on a three-coordinated titanyl group (as well as possible five- or six-coordinated active sites), are discounted. Comparable XAFS studies of soluble catalytically active four-coordinated Ti(IV)-containing molecular entities establish that the heterogeneous Ti-SiO2 catalyst has "single-site" active centers. Equipped with such information, minute changes in hydrophobicity and local composition (e.g., replacement of one Si by a Ge) can be wrought so as to boost the performance of the catalyst. The merits of using combined in situ X-ray absorption spectroscopic and X-ray diffractometric measurements are also highlighted.

The architecture of Mg(II) centres in MAPO-36 solid acid catalysts

The local structure around Mg2+ ions of a Magnesium substituted aluminophosphate, with the ATS structure (MgAPO-36, Mg/P=0.08), in the as-prepared and calcined state has been investigated by Mg K-edge XAS spectroscopy. High quality XAS data were collected using the solid-state fluorescence detector. Mg2+ is found to replace tetrahedrally co-ordinated Al3+ in the as-prepared state and remained intact even after calcination, thus yielding a highly active, solid acid catalyst.

The role of XAFS in the in situ and ex situ elucidation of active sites in designed solid catalysts

New mesoporous and microporous catalysts based on silica, aluminophosphates, or aluminophosphates containing one or other of the heteroatoms Ti, Co, Mn, Fe and Cr, are ideally suited for study by X-ray absorption fine structure (XAFS). The information derived from X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) elucidates the nature of the catalytically active site, generally (but not invariably) under in situ conditions. This, in turn, provides new insights into the mechanism of the catalysis and suggests methods of improving the performance of the original catalyst. In this way, significant advances have recently been made in designing catalysts for the selective oxidation of alkanes, for the epoxidation of alkenes and for the dehydration of alcohols to yield olefins. Combined with density functional theory (DFT) computations, XAFS studies have also yielded fresh insights into the architecture of nanoparticle catalysts, such as Ru12Cu4C2 supported on mesoporous silica.

Molecular sieve catalysts for the regioselective and shape- selective oxyfunctionalization of alkanes in air

Framework-substituted, molecular-sieve, aluminophosphate, microporous solids are the centerpieces of a new approach to the aerobic oxyfunctionalization of saturated hydrocarbons. The sieves, and the few percent of the Al(III) sites within them that are replaced by catalytically active, transition-metal ions in high oxidation states (Co(III), Mn(III), Fe(III)), are designed so as to allow free access of oxygen in to and out of the interior of these high-area solids. Certain metal-substituted, molecular sieves permit only end-on approach of linear alkanes to the active centers, thereby favoring enhanced reactivity of the terminal methyl groups. By optimizing cage dimension, with respect to that of the hydrocarbon reactant, as well as adjusting the average separation of active centers within a cage, and by choosing the sieve with the appropriate pore aperture, highly selective conversions such as n-hexane to hexanoic acid or adipic acid, and cyclohexane to cyclohexanol, cyclohexanone, or adipic acid, may be effected at low temperature, heterogeneously in air.

Effect of Si(IV) substitution on the stability of microporous ZnAPSO-44 solid acid catalysts: a combined XAS/XRD study

The combined XAS/XRD technique has been used to investigate the stability of the microporous structure during calcination process for a series of ZnAPSO-44 materials. Incorporation of large amounts of Zn is found to produce materials that are unstable upon removal of the structure directing organic template molecule. However, simultaneous incorporation of Si is found to increase the thermal stability of the materials, yielding catalysts that are well suited for acid catalysed reactions.

The site occupancy of Mg in the brownmillerite structure and its effect on hydration properties: an X-ray/neutron diffraction and EXAFS study

Samples of pure (Ca2FeAlO5) and lightly doped (Ca2Fe0.95Al0.95Mg0.05Si0.05O5) brownmillerite have been synthesized. Synchrotron X-ray and neutron diffraction data have been collected so that the structures can be refined using, simultaneously, both diffraction data sets and known compositional information; this overcomes the problem of under-determinacy resulting from multi-occupation of the tetrahedrally and octahedrally coordinated sites in the structure. For the pure form, a 2.7:1 iron/aluminium preference for octahedral/tetrahedral (respectively) occupation is obtained. This trend is reflected also in the doped brownmillerite, though, because of the low level of Mg doping, the occupancy of Mg is only resolved through the additional use of Mg EXAFS (extended X-ray absorption fine structure) data, which shows that Mg displays a distinct octahedral site preference rather than a disordered occupation between the octahedral/tetrahedral sites. The consequences of Mg doping are then examined using time-resolved multi-angle energy-dispersive powder X-ray diffraction studies of the mineral undergoing hydration; this shows that the pure form is more active than the doped form.

Use of YB(66) as monochromator crystals for soft-energy EXAFS

YB(66)(400) crystals present a new advance in monochromator crystals suitable for use at energies below 2 keV. In this paper a comparison of their performance with that provided by the more usual beryl and quartz crystals, which cover the same energy range, is presented. In general, the YB(66) crystals are much superior; however, they do exhibit a pair of large 'crystal glitch'-type features in the 1380-1440 eV region. These fall in the Mg K-EXAFS region and so can present a serious problem in studies of this edge for a wide range of materials. An important class of materials so afflicted are magnesium-substituted aluminophosphate molecular sieves (zeolites), which are used in many applications, in particular as solid acid catalysts for conversion of methanol to hydrocarbon.