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Hegde G, Mondal SK, Hegde G, Jagadeesh G, Asokan S. Blast wave pressure measurement and analysis in air and granular media inside a shock tube using a fiber Bragg grating sensor. Rev Sci Instrum 2024; 95:045003. [PMID: 38602459 DOI: 10.1063/5.0187068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 03/24/2024] [Indexed: 04/12/2024]
Abstract
In this work, we have demonstrated the use of a fiber Bragg grating (FBG) sensor to measure the pressure profile of blast waves generated inside a vertical shock tube (VST). An FBG pressure sensor probe has been designed and developed that can be incorporated into the wall of the VST. The VST facility is used to generate blast waves with decay times of the order of a few milliseconds to simulate explosive events. Pressure measurement experiments have been carried out at different incident blast wave peak pressures inside the VST. The FBG pressure sensor measurements are validated against a standard piezoelectric pressure transducer at an acquisition rate of 1 MHz. The pressure signals of both sensors are found to match well with similar rise times and decay profiles. The validated FBG pressure sensor is then incorporated into a sand column mounted in the test section of the VST to measure the pressure profile of blast wave-induced stress waves in granular media. The FBG and piezoelectric pressure sensor data are compared using fast Fourier transform analysis and continuous wavelet transform. The feasibility of FBG sensors for blast pressure measurement under harsh conditions imposed inside shock tube environments is established.
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Affiliation(s)
- Gautam Hegde
- Instrumentation and Applied Physics, Indian Institute of Science, Bengaluru 560012, Karnataka, India
| | - Suraj Kumar Mondal
- Department of Aerospace Engineering, Indian Institute of Science, Bengaluru 560012, Karnataka, India
| | - Gopalkrishna Hegde
- Department of Aerospace Engineering, Indian Institute of Science, Bengaluru 560012, Karnataka, India
| | - G Jagadeesh
- Department of Aerospace Engineering, Indian Institute of Science, Bengaluru 560012, Karnataka, India
| | - S Asokan
- Instrumentation and Applied Physics, Indian Institute of Science, Bengaluru 560012, Karnataka, India
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Nath B, Behera SK, Kumar J, Hemmerle A, Fontaine P, Ramamurthy PC, Mahapatra DR, Hegde G. Understanding the Heterointerfaces in Perovskite Solar Cells via Hole Selective Layer Surface Functionalization. Adv Mater 2024; 36:e2307547. [PMID: 38030567 DOI: 10.1002/adma.202307547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 11/27/2023] [Indexed: 12/01/2023]
Abstract
Interfaces in perovskite solar cells (PSCs) play a pivotal role in determining device performance by influencing charge transport and recombination. Understanding the physical processes at these interfaces is essential for achieving high-power conversion efficiency in PSCs. Particularly, the interfaces involving oxide-based transport layers are susceptible to defects like dangling bonds, excess oxygen, or oxygen deficiency. To address this issue, the surface of NiOx is passivated using octadecylphosphonic acid (ODPA), resulting in improved charge transport across the perovskite hole transport layer (HTL) interface. This surface treatment has led to the development of hysteresis-free devices with an impressive ≈13% increase in power conversion efficiency. Computational studies have explored the halide perovskite architecture of ODPA-treated HTL/Perovskite, aiming to unlock superior photovoltaic performance. The ODPA surface functionalization has demonstrated enhanced device performance, characterized by superior charge exchange capacity. Moreover, higher band-to-band recombination in photoluminescence and electroluminescence indicates presence of lower mid-gap energy states, thereby increasing the effective photogenerated carrier density. These findings are expected to promote the utilization of various phosphonic acid-based self-assembly monolayers for surface passivation of oxide-based transport layers in perovskite solar cells. Ultimately, this research contributes to the realization of efficient halide PSCs by harnessing the favorable architecture of NiOx interfaces.
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Affiliation(s)
- Bidisha Nath
- Interdisciplinary Centre for Energy Research, Indian Institute of Science, Bengaluru, Karnataka, 560012, India
| | - Sushant K Behera
- Department of Materials Engineering, Indian Institute of Science, Bengaluru, Karnataka, 560012, India
| | - Jeykishan Kumar
- Interdisciplinary Centre for Energy Research, Indian Institute of Science, Bengaluru, Karnataka, 560012, India
| | - Arnaud Hemmerle
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, 91190, France
| | - Philippe Fontaine
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, 91190, France
| | - Praveen C Ramamurthy
- Interdisciplinary Centre for Energy Research, Indian Institute of Science, Bengaluru, Karnataka, 560012, India
- Department of Materials Engineering, Indian Institute of Science, Bengaluru, Karnataka, 560012, India
| | - Debiprosad Roy Mahapatra
- Centre for Biosystems Science and Engineering, Indian Institute of Science, Bengaluru, Karnataka, 560012, India
| | - Gopalkrishna Hegde
- Department of Aerospace Engineering, Indian Institute of Science, Bengaluru, Karnataka, 560012, India
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Pillai JK, Chari B, Hegde G, Chapman P, Halls M, Botchu R. Imaging in international sporting event: experience from the Birmingham Commonwealth Games 2022. Clin Radiol 2023; 78:e477-e485. [PMID: 36958956 DOI: 10.1016/j.crad.2023.02.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 02/20/2023] [Accepted: 02/22/2023] [Indexed: 03/12/2023]
Abstract
AIM To explain the design and delivery of diagnostic imaging and image-guided intervention services for an international games. The authors share their experiences from the Birmingham Commonwealth Games 2022. MATERIALS AND METHODS A retrospective analysis was undertaken of anonymised data from the Zillion, Easyvision (RIS and PACS), and Encounter platforms for image viewing, interpretation and reporting during the Games. The data collected included age and gender, type of sport, nature of the injury, and imaging findings with diagnoses. RESULTS The number of individuals who had radiological investigations at the Birmingham Commonwealth Games was 518 and the vast majority of them were athletes (90 %). The average age of athletes who had imaging was 28 years and that of non-athletes who accessed imaging services was 46.4 years with male predominance. Magnetic resonance imaging was the most frequently used imaging technique and the lower limb was the most frequently imaged body part. Athletes playing netball and beach volleyball had the highest percentage of injuries. CONCLUSION The authors share their experience from the Birmingham Commonwealth Games 2022 regarding the nuances and challenges in radiology service provision for an international sports event that would be helpful for musculoskeletal radiologists in the design and delivery of similar international events in the future.
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Affiliation(s)
- J K Pillai
- Department of Radiology, London North West University Healthcare NHS Trust, UK.
| | - B Chari
- Department of Radiology, Nuffield Orthopaedic Centre, Oxford University Hospitals NHS Foundation Trust, UK
| | - G Hegde
- Department of Musculoskeletal Radiology, Royal Orthopaedic Hospital NHS Foundation Trust, Birmingham, UK
| | - P Chapman
- Department of Radiology, Hampshire Hospitals NHS Foundation Trust, UK
| | - M Halls
- Department of Radiology, Worcestershire Royal Hospital, UK
| | - R Botchu
- Department of Musculoskeletal Radiology, Royal Orthopaedic Hospital NHS Foundation Trust, Birmingham, UK
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Ramakrishnan RK, Ravichandran AB, Kaushik I, Hegde G, Talabattula S, Rohde PP. The Quantum Internet: A Hardware Review. J Indian Inst Sci 2022. [DOI: 10.1007/s41745-022-00336-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Smith E, Hegde G, Czyz M, Hughes S, Haleem S, Grainger M, James SL, Botchu R. A Radiologists' Guide to En Bloc Resection of Primary Tumors in the Spine: What Does the Surgeon Want to Know? Indian J Radiol Imaging 2022; 32:205-212. [PMID: 35924121 PMCID: PMC9340175 DOI: 10.1055/s-0042-1744162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/30/2022] Open
Abstract
AbstractEn bloc resection in the spine is performed for both primary and metastatic bone lesions and has been proven to lengthen disease-free survival and decrease the likelihood of local recurrence. It is a complex procedure, which requires a thorough multi-disciplinary approach. This article will discuss the role of the radiologist in characterizing the underlying tumor pathology, staging the tumor and helping to predict possible intraoperative challenges for en bloc resection of primary bone lesions. The postoperative appearances and complications following en bloc resection in the spine will be considered in subsequent articles.
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Affiliation(s)
- E. Smith
- Department of Musculoskeletal Imaging, Royal Orthopaedic Hospital, Birmingham, United Kingdom
| | - G. Hegde
- Department of Musculoskeletal Imaging, Royal Orthopaedic Hospital, Birmingham, United Kingdom
| | - M. Czyz
- Department of Spinal Surgery, Royal Orthopaedic Hospital, Birmingham, United Kingdom
| | - S. Hughes
- Department of Spinal Surgery, Royal Orthopaedic Hospital, Birmingham, United Kingdom
| | - S. Haleem
- Department of Spinal Surgery, Royal Orthopaedic Hospital, Birmingham, United Kingdom
| | - M. Grainger
- Department of Spinal Surgery, Royal Orthopaedic Hospital, Birmingham, United Kingdom
| | - S. L. James
- Department of Musculoskeletal Imaging, Royal Orthopaedic Hospital, Birmingham, United Kingdom
| | - R. Botchu
- Department of Musculoskeletal Imaging, Royal Orthopaedic Hospital, Birmingham, United Kingdom
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R V, Hegde G, Botchu R. MRI imaging of soft tissues tumours and tumour like lesions-SLAM approach. J Clin Orthop Trauma 2022; 28:101872. [PMID: 35494486 PMCID: PMC9046452 DOI: 10.1016/j.jcot.2022.101872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 02/22/2022] [Accepted: 04/13/2022] [Indexed: 10/18/2022] Open
Abstract
Imaging is vital in characterising and delineating the extent of soft tissue tumours and there is abundant literature on this. A simplified approach is required to characterise the lesions on MR and we describe a simplified street-smart approach called SLAM (signal, location, age, multiplicity and matrix).
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Affiliation(s)
| | - G. Hegde
- Department of Musculoskeletal Radiology, Royal Orthopedic Hospital, Birmingham, UK
| | - R. Botchu
- Department of Musculoskeletal Radiology, Royal Orthopedic Hospital, Birmingham, UK,Corresponding author. Royal Orthopedic Hospital, Bristol Road South, Northfield, Birmingham, UK.
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Smith E, Hegde G, Czyz M, Grainger M, James S, Botchu R. A guide to assessing post-operative complications following en bloc spinal resection. J Clin Orthop Trauma 2021; 23:101653. [PMID: 34745878 PMCID: PMC8551820 DOI: 10.1016/j.jcot.2021.101653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 10/05/2021] [Accepted: 10/12/2021] [Indexed: 10/20/2022] Open
Abstract
En-bloc resection of spinal tumours is a complex procedure with significant morbidity and mortality. The extensive resection leaves a large soft tissue and osseous defect requiring reconstruction. Following en-bloc resection, there may be complications relating to both the removal of the tumour and the subsequent reconstruction. This paper outlines the imaging appearances of the frequently encountered complications in our experience. The primary aim is to improve the confidence of the radiologist when reporting imaging following spinal en-bloc resection, however we believe this is also useful for the spinal and orthopaedic surgeons in assessing the patients following en block resection.
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Affiliation(s)
- E. Smith
- Department of Musculoskeletal Imaging, Royal Orthopaedic Hospital, Birmingham, UK
| | - G. Hegde
- Department of Musculoskeletal Imaging, Royal Orthopaedic Hospital, Birmingham, UK
| | - M. Czyz
- Department of Spinal Surgery, Royal Orthopaedic Hospital, Birmingham, UK
| | - M. Grainger
- Department of Spinal Surgery, Royal Orthopaedic Hospital, Birmingham, UK
| | - S.L. James
- Department of Musculoskeletal Imaging, Royal Orthopaedic Hospital, Birmingham, UK
| | - R. Botchu
- Department of Musculoskeletal Imaging, Royal Orthopaedic Hospital, Birmingham, UK,Corresponding author. Department of Musculoskeletal Radiology, The Royal Orthopedic Hospital, Bristol Road South, Northfield, Birmingham, UK.
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Hegde G, Azzopardi C, Davies A, Patel A, James S, Botchu R. Spinal collision lesions. J Clin Orthop Trauma 2021; 19:21-25. [PMID: 34046296 PMCID: PMC8141933 DOI: 10.1016/j.jcot.2021.05.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Revised: 03/03/2021] [Accepted: 05/05/2021] [Indexed: 12/27/2022] Open
Abstract
UNLABELLED Collision lesions are rare neoplasms often described in the hepatobiliary system, genitourinary system and adrenal glands. Vertebral haemangiomas (VH) are the most common lesions involving the vertebral bodies. VHs are usually asymptomatic and considered as "Do not touch" lesions. Rarely they can be symptomatic. Imaging findings of typical and atypical haemangiomas, variant forms of haemangioma such as aggressive haemangiomas are well known. Collision lesions involving VHs are extremely rare. This article presents a series of cases with collision lesions of the vertebral body involving VHs. ADVANCES IN KNOWLEDGE This Case series demonstrates the various collision lesions in spinal haemangioma.
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Affiliation(s)
| | | | | | | | | | - R. Botchu
- Corresponding author. Department of Musculoskeletal Radiology, The Royal Orthopedic Hospital, Bristol Road South, Northfield, Birmingham, UK.
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Hegde G, Subramanian A, Azzopardi C, Patel A, James SL, Botchu R. Iliotibial band enthesopathy: an unusual cause of lateral knee pain post total knee replacement. J Ultrasound 2021; 25:83-87. [PMID: 33591565 PMCID: PMC8964855 DOI: 10.1007/s40477-021-00565-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 01/25/2021] [Indexed: 11/26/2022] Open
Abstract
Iliotibial band (ITB) pathology is one of the main causes of lateral knee pain. The enthesopathy of the ITB at its insertion post total knee replacement (TKR) is a rare cause of lateral knee pain. We describe a series of cases of ITB enthesopathy with sonographic findings and management.
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Affiliation(s)
- G Hegde
- Department of Musculoskeletal Imaging, Department of Musculoskeletal Radiology, The Royal Orthopaedic Hospital, Bristol Road South, Northfield, Birmingham, UK
| | - A Subramanian
- Department of Musculoskeletal Imaging, Department of Musculoskeletal Radiology, The Royal Orthopaedic Hospital, Bristol Road South, Northfield, Birmingham, UK
| | - C Azzopardi
- Department of Musculoskeletal Imaging, Department of Musculoskeletal Radiology, The Royal Orthopaedic Hospital, Bristol Road South, Northfield, Birmingham, UK
| | - A Patel
- Department of Musculoskeletal Imaging, Department of Musculoskeletal Radiology, The Royal Orthopaedic Hospital, Bristol Road South, Northfield, Birmingham, UK
| | - S L James
- Department of Musculoskeletal Imaging, Department of Musculoskeletal Radiology, The Royal Orthopaedic Hospital, Bristol Road South, Northfield, Birmingham, UK
| | - Rajesh Botchu
- Department of Musculoskeletal Imaging, Department of Musculoskeletal Radiology, The Royal Orthopaedic Hospital, Bristol Road South, Northfield, Birmingham, UK.
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Shenoy BM, Hegde G, Roy Mahapatra D. Field enhancement in microfluidic semiconductor nanowire array. Biomicrofluidics 2020; 14:064102. [PMID: 33163137 PMCID: PMC7609134 DOI: 10.1063/5.0028899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 10/15/2020] [Indexed: 06/11/2023]
Abstract
Nano-material integrated microfluidic platforms are increasingly being considered to accelerate biological sample preparation and molecular diagnostics. A major challenge in this context is the generation of high electric fields for electroporation of cell membranes. In this paper, we have studied a novel mechanism of generating a high electric field in the microfluidic channels by using an array of semiconductor nanowires. When an electrostatic field is applied across a semiconductor nanowire array, the electric field is localized near the nanowires and the field strength is higher than what was reported previously with various other micro-geometries. Nanowires made of ZnO, Si, and Si-SiO2 and their orientation and array spacing are considered design parameters. It is observed that for a given ratio of the spacing between nanowires to the diameter, the electric field enhancement near the edges of ZnO nanowires is nearly 30 times higher compared to Si or Si-SiO2 nanowire arrays. This enhancement is a combined effect of the unique geometry with a pointed tip with a hexagonal cross section, the piezoelectric and the spontaneous polarization in the ZnO nanowires, and the electro-kinetics of the interface fluid. Considering the field localization phenomena, the trajectories of E. coli cells in the channel are analyzed. For a given inter-nanowire spacing and an applied electric field, the channels with ZnO nanowire arrays have a greater probability of cell lysis in comparison to Si-based nanowire arrays. Detailed correlations between the cell lysis probability with the inter-nanowire spacing and the applied electric field are reported.
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Affiliation(s)
- Bhamy Maithry Shenoy
- Department of Aerospace Engineering, Indian Institute of Science, Bangalore 560012, India
| | - Gopalkrishna Hegde
- BioSystems Science and Engineering, Indian Institute of Science, Bangalore 560012, India
| | - D. Roy Mahapatra
- Department of Aerospace Engineering, Indian Institute of Science, Bangalore 560012, India
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A K J, Garg K, Ramamurthy PC, Mahapatra DR, Hegde G. Moldable biomimetic nanoscale optoelectronic platforms for simultaneous enhancement in optical absorption and charge transport. Nanoscale 2018; 10:3730-3737. [PMID: 29411826 DOI: 10.1039/c7nr09015c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Nano-scale patterns such as those found on the exterior surface of the eyes of certain nocturnal insects have far-reaching implications in terms of optoelectronic device design. The advantage of using these patterns for optoelectronic enhancement in photovoltaic light harvesting has been less explored due to the lack of suitable engineered materials to easily fabricate such nanostructures. Here, an attempt is made to realize these complex patterns using a self-assembly based molding process on hitherto unexplored robust structural epoxies with excellent repeatability and scalability to a larger area. The incorporation of these patterns in the substrate shows nearly a 50% broadband drop in the specular reflectance of the nanostructured substrate. Furthermore, it is demonstrated that by tweaking the bio-inspired patterns on the interior side of a light harvesting device, it is possible to obtain a broadband improvement in the external quantum efficiency in the spectral window between 350 and 650 nm leading to a significant improvement of up to 49% in the photocurrent density in the structured devices. From our experiment and simulations, it is observed that this enhancement stems from a combination of two effects: first, a broadband drop in the specular reflectance exceeding 70%, arising from trapped surface plasmon-polariton modes, and second, an improved charge separation in the structured device arising due to perturbed built-in electric fields. Furthermore, the simulations which take into account the interfacial nano-scale morphology show that for absorbers with low carrier mobilities, a significant improvement in the photocurrent and in the fill factor is simultaneously possible. Overall, this work demonstrates a combination of tweaked bio-mimetic design and the use of unconventional robust structural materials as nanostructured optoelectronic substrates. This effort can bridge the gap between naturally evolved designs and practical optoelectronics to enhance the performance.
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Affiliation(s)
- Jagdish A K
- Center for Nano Science and Engineering, Indian Institute of Science, Bangalore, India560012.
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Sagar HP, Mahalingam V, Mahapatra DR, Hegde G, Hanagud S, Rahman MR. Transient dynamic distributed strain sensing using photonic crystal waveguides. Appl Opt 2017; 56:7877-7885. [PMID: 29047773 DOI: 10.1364/ao.56.007877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 09/01/2017] [Indexed: 06/07/2023]
Abstract
This paper presents a new type of one-dimensional photonic crystal (PC) waveguide sensor and a technique for prediction of transient strain response accurately. The PC waveguide is integrated on a silicon substrate. We investigate the effect of non-uniform strain localization on the optical signal and use that information to capture the transient strain. Wavelength shift due to distributed strain field is modeled by incorporating the mechanically deformed geometry and photo-acoustic coupling through Pockels effect in a finite element formulation. We demonstrate the advantages of using our proposed method, where multiple spectral peak shift is used instead of single peak shift in order to improve sensing output accuracy and also to estimate the sensor parameter regressively, where the signal's bandwidth is limited. The maximum sensitivity of the waveguide sensor in terms of wavelength shift is estimated to be 0.36 pm/μstrain in single-peak-based sensing, whereas the proposed adaptive multispectral estimation scheme shows an enhanced sensitivity of 4.029 pm/μstrain.
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Sreenivasulu T, Kolli VR, Yadunath TR, Badrinarayana T, Sahu A, Hegde G, Mohan S, Srinivas T. Photonic Crystal-Based force Sensor to Measure Sub-Micro Newton forces over a Wide Range. CURR SCI INDIA 2016. [DOI: 10.18520/cs/v110/i10/1989-1994] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Abstract
We describe the fabrication of silver nanotriangle array using angle resolved nanosphere lithography and utilizing the same for enhancing fluorescence. The well established nanosphere lithography is modified by changing the angle of deposition between the nanosphere mask and the beam of silver being deposited resulting in nanotriangles of varying surface area and density. The 470 nm plasmon resonance wavelength of the substrate was determined using minimum reflectivity method which closely matches with excitation wavelength of the fluorophore. Ten times enhancement in fluorescence emission intensity is obtained from fluorescein isothiocyanate coated on top of silver nanotriangle array separated by a spacer layer of poly vinyl alcohol as compared to glass. The enhanced fluorescence emission is attributed to the increase in local field enhancement.
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Affiliation(s)
- Ravi Kumar Kannadorai
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 639798, Singapore
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Abstract
The concept of starting up a batch, high-solids anaerobic digester by simply flooding the bed with a pH-buffer solution was tested using a mixture of vegetable waste and wood chips as feedstock at mesophilic (38 degrees C) and thermophilic (55 degrees C) conditions. At both temperatures stable and balanced methanogenesis was rapidly established within four days and was sustained until substrate was exhausted. Methanogenesis was more rapidly initiated in the thermophilic digester than in the mesophilic digester. Acetic, propionic and butyric acids accumulated in the leachate of both digesters during the start-up of digestion of uninoculated batch of waste. Thereafter all acids were degraded; which was quicker in the thermophilic digester. The accumulation and degradation of these acids was slower in the mesophilic digester. These studies showed that inoculum for carrying out thermophilic and mesophilic anaerobic digestion is readily available within the waste and its activity for complete mineralization of organic matter can be enhanced and sustained by providing adequate alkalinity. By employing a process in which anaerobic digestion of subsequent batches of waste was carried out by flooding with leachate drained from the digestion of a previous batch of waste, the volatile organic acid accumulation was maintained low and 95% of the methane yield potential of the waste was produced in 11 days under thermophilic conditions as opposed to 27 days under mesophilic conditions.
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Affiliation(s)
- G Hegde
- School of Environmental Science, Murdoch University, Perth, WA 6150, Australia
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Shastri S, Hegde G, Mroszczak E, Herschler R. Influence of variation in spray-dried lactose quality on in vitro dissolution and bioavailability of an experimental oxfendazole bolus for cattle. Am J Vet Res 1982; 43:714-7. [PMID: 7073097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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