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Journal of Ocean Engineering and Science 2016年第3期1卷 186-202页

作者： Dikshant Singh Saini Debasis Karmakar Samit ray-chaudhuri Department of Civil Engineering Indian Institute of Technology KanpurKanpurUP 208016India

Tubular structures are widely used in offshore installations,trusses,high rise buildings,towers for wind turbines,ski-lift installations,lightning,road pole signals etc.,owing to their excellent structural performance and attractive *** concentration,especially in the welded joints of these structures,is an important design consideration particularly for fatigue *** the context of tubular and non-tubular joints,this paper provides a review of the experimental and numerical studies that have been carried out so far to determine the stress concentration factor(SCF).Emphasis is also placed on the complexity of capturing different types of stresses in tubular/non-tubular joints for estimation of *** code provisions for evaluation of SCF are also ***,a few issues,which require significant research effort to advance our understanding and to improve the current design guidelines,have been identified.©2016 Shanghai Jiaotong *** by Elsevier B.V.

关键词： Hot-spot stress Stress concentration factor(SCF) Fatigue Tubular joints Non-tubular joints

Effect of sodium arsenite on spermatogenesis, plasma gonadotrophins and testosterone in rats

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Asian Journal of Andrology 2003年第1期5卷 27-31页

作者： Mahitosh Sarkar Gargi ray chaudhuri Aloke Chattopadhyay Narendra Mohan Biswas Reproductive Physiology Unit Dept. of Physiology University Colleges of Science and Technology Calcutta University Calcutta-700 009 India

To investigate the effect of arsenic on spermatogenesis. Methods: Mature (4 months old) Wistar rats were intraperitoneally administered sodium arsenite at doses of 4, 5 or 6 mg-kg^-day1 for 26 days. Different varieties of germ cells at stage VII seminiferous epithelium cycle, namely, type A spermatogonia (ASg), preleptotene spermatocytes (pLSc), midpachytene spermatocytes (mPSc) and step 7 spermatids (7Sd) were quantitatively evaluated, along with radioimmunoassay of plasma follicle-stimulating hormone (FSH), lutuneizing hormone (LH), testosterone and assessment of the epididymal sperm count. Results: In the 5 and 6 mg/kg groups, there were significant dose-dependent decreases in the accessory sex organ weights, epididymal sperm count and plasma concentrations of LH, FSH and testosterone with massive degeneration of all the germ cells at stage VII. The changes were insignificant in the 4 mg/kg group. Conclusion: Arsenite has a suppressive influence on spermatogenesis and gonadotrophin and testosterone release in rats.

关键词： arsenite spermatogenesis gonadotrophins testosterone testis

NONMOTOR SYMPTOMS—THE HIDDEN FACE OF PARKINSON'S DISEASE Identification and Managment

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Structural, microstructural, and thermal characterizations of a chalcopyrite concentrate from the Singhbhum shear zone, India

2018第七届国际帕金森病及运动障碍学术会议西湖论坛

作者： K ray chaudhuri (ray chaudhuri) National Parkinson Foundation International Centre of Excellence Kings College HospitalKings College

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International Journal of Minerals,Metallurgy and Materials 2015年第3期22卷 225-232页

作者： Ritayan Chatterjee Shamik chaudhuri Saikat Kumar Kuila Dinabandhu Ghosh Department of Metallurgical and Materials Engineering Jadavpur University Division of Materials Engineering Lund University

The structural and morphological characterizations of a chalcopyrite concentrate, collected from the Indian Copper Complex, Ghatshila, India, were carried out by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The con- centmte powder was composed mainly of free chalcopyrite and low quartz in about 3：1 weight ratio. The particle size was about 100 μm. Spectroscopic studies （FTIR, Raman, UV-visible） of the concentrate supported the XRD findings, and also revealed a marginal oxidation of the sulfide phase. The energy band gap of the sulfide was found to be 3.4 eV. Differential thermal analysis and thermogravimetry of the con- centrate showed a decomposition of chalcopyrite at 658 K with an activation energy of 208 kJ-mol 1, and two successive structural changes of silica at 848 K and 1145 K.

关键词： chalcopyrite structural properties microstructure thermal characteristics

Petrography of Middle Jurassic to Early Cretaceous sandstones in the Kutch Basin,western India:Implications on provenance and basin evolution

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Journal of Palaeogeography 2018年第3期7卷 239-252页

作者： Angana chaudhuri Santanu Banerjee Emilia Le Pera Department of Earth Sciences Indian Institute of Technology Bombay Dipartimento di Biologia Ecologia e Scienze della Terra University della

This paper investigates the provenance of Middle Jurassic to Early Cretaceous sediments in the Kutch Basin, western India, on the basis of mineralogical investigations of sandstones composition （Quartz-Feldspar-Lithic （QFL） fragment）, Zircon-Tourmaline-Rutile （ZTR） index, and mineral chemistry of heavy detrital minerals of the framework. The study also examines the compositional variation of the sandstone in relation to the evolution of the Kutch Basin, which originated as a rift basin during the Late Triassic and evolved into a passive margin basin by the end Cretaceous. This study analyzes sandstone samples of Jhumara, Jhuran and Bhuj Formations of Middle Jurassic, Upper Jurassic and Lower Cretaceous, respectively, in the Kutch Mainland. Sandstones record a compositional evolution from arkosic to subarkosic as the feldspar content decreases from 68% in the Jhumara Formation to 27% in the Bhuj Formation with intermediate values in the Jhuran Formation. The QFL modal composition indicates basement uplifted and transitional continental settings at source. Heavy mineral content of these sandstones reveals the occurrence of zircon, tourmaline, rutile, garnet, apatite, monazite and opaque minerals. Sub-rounded to well-rounded zircon grains indicate a polycyclic origin. ZTR indices for samples in Jhumara, Jhuran and Bhuj Formations are 25%, 30% and 50% respectively. Chemistry of opaque minerals reveals the occurrence of detrital varieties such as ilmenite, rutile, hematite/magnetite and pyrite, in a decreasing order of abundances. Chemistry of ilmenites in the Jhumara Formation reveals its derivation from dual felsic igneous and metabasic source, while those in Jhuran and Bhuj Formations indicate a metabasic derivation. Chemistry of garnet reveals predominantly Fe-rich （almandine） variety of metabasic origin. X-ray microscopic study provides the percentage of heavy minerals ranging from 3% to 5.260. QFL detrital modes reflect the evolution of the basin from an active rif

关键词： Siliciclastic provenance Tectonic setting Heavy minerals Mineral chemistry X-ray microscopy Mesozoic,Kutch Basin

Why do‘OFF’periods still occur during continuous drug delivery in Parkinson’s disease?

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Translational Neurodegeneration 2022年第1期11卷 280-293页

作者： Silvia Rota Daniele Urso Daniel J.van Wamelen Valentina Leta Iro Boura Per Odin Alberto J.Espay Peter Jenner K.ray chaudhuri Department of Basic and Clinical Neurosciences Institute of PsychiatryPsychology and NeuroscienceKing’s College LondonLondonUK Parkinson’s Foundation Centre of Excellence King’s College HospitalLondonUK Department of Neuroimaging Institute of PsychiatryPsychology and NeuroscienceKing’s College LondonLondonUK Centre for Neurodegenerative Diseases and the Aging Brain Department of Clinical Research in NeurologyUniversity of Bari‘Aldo Moro“Pia Fondazione Cardinale G.Panico”73039 TricaseItaly Donders Institute for Brain Cognition and BehaviourDepartment of NeurologyRadboud University Medical CentreNijmegenThe Netherlands School of Medicine University of CreteCreteGreece Department of Neurology University Hospital of HeraklionCreteGreece Division of Neurology Department of Clinical Sciences LundLund UniversityLundSweden University of Cincinnati Gardner Neuroscience Institute Gardner Family Center for Parkinson’s Disease and Movement DisordersDepartment of NeurologyUniversity of CincinnatiCincinnatiOHUSA Institute of Pharmaceutical Sciences Faculty of Life Science and MedicineKing’s College LondonLondonUK.

Continuous drug delivery(CDD)is used in moderately advanced and late-stage Parkinson’s disease(PD)to control motor and non-motor fluctuations(‘OFF’periods).Transdermal rotigotine is indicated for early fluctuations,while subcutaneous apomorphine infusion and levodopa-carbidopa intestinal gel are utilised in advanced *** three strategies are considered examples of continuous dopaminergic stimulation achieved through CDD.A central premise of the CDD is to achieve stable control of the parkinsonian motor and non-motor states and avoid emergence of‘OFF’***,data suggest that despite their efficacy in reducing the number and duration of‘OFF’periods,these strategies still do not prevent‘OFF’periods in the middle to late stages of PD,thus contradicting the widely held concepts of continuous drug delivery and continuous dopaminergic *** these emergent‘OFF’periods still occur is *** this review,we analyse the potential reasons for their *** contribution of drug-and device-related involvement,and the problems related to site-specific drug delivery are *** propose that changes in dopaminergic and non-dopaminergic mechanisms in the basal ganglia might render these persistent‘OFF’periods unresponsive to dopaminergic therapy delivered via CDD.

关键词： ‘OFF’periods Continuous drug delivery Continuous dopaminergic stimulation Rotigotine patch Subcutaneous apomorphine infusion Levodopa-carbidopa intestinal gel

Optimization and application of UVC irradiation for prevention of fungal biodeterioration of vegetable tanned and chrome tanned leather

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Journal of Leather Science and Engineering 2022年第2期4卷 380-393页

作者： Eshita Jhahan Subarna Bhattacharyya Anirban chaudhuri Nirmal Sarkar Shaheen Akhtar Punarbasu chaudhuri School of Environmental Studies Jadavpur UniversityKolkata 700032India Department of Environmental Science University of CalcuttaKolkataIndia.

UV-C irradiation critically effects the growth of micro-fungi and also deteriorate leather materials. In the present study vegetable tanned and chrome tanned leather were infected with pure cultures of Aspergillus niger and Aspergillus flavus, which were isolated from stored leather materials. UV-C light (λ = 254 nm) was applied on infected leather for 15 and 60 min. The changes in leather qualities were examined through weight, tensile strength, scanning electron microscope, energy dispersive X-ray and Fourier transform infrared spectroscopy study after 15 and 30 days of fungal inoculation. Vegetable tanned leather was more vulnerable in case of fungal attack than chrome tanned leather while A. flavus showed more influence on leather deterioration than A. niger. The results showed that weight loss after 30 days for 15 and 60 min irradiation exposure was 1.3% compared to A. flavus infected leather (3.93%). The tensile strength of vegetable and chrome tanned UV irradiated leather was increased by 44% and 7% respectively. The scanning electron microscopic images exhibit the limited presence of conidiophores in UV-C exposed leather which confirmed the potentiality of irradiation for controlling fungal growth. The infrared spectral analysis of UV-C exposed infected leather samples showed neither shifting of wavenumber nor displacement of any functional groups. Alto-gether the efficacy of UV-C irradiation against biodeterioration of leather was concluded to be effective. This method can be used to control fungal growth without compromising the leather quality.

关键词： Aspergillus Biodeterioration Leather SEM Tensile strength UV-C

Kinetic studies on the reduction of iron ore nuggets by devolatilization of lean-grade coal

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International Journal of Minerals,Metallurgy and Materials 2016年第12期23卷 1360-1368页

作者： Chanchal Biswas Prithviraj Gupta Arnab De Mahua Ghosh chaudhuri Rajib Dey Department Metallurgical and Material Engineering Jadavpur University Department of Metallurgy and Materials Engineering Indian Institute of EngineeringScience & Technology School of Materials Science and Nano Technology Jadavpur University

An isothermal kinetic study of a novel technique for reducing agglomerated iron ore by volatiles released by pyrolysis of lean-grade non-coking coal was carried out at temperature from 1050 to 1200℃ for 10-120 min. The reduced samples were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and chemical analysis. A good degree of metallization and reduction was achieved. Gas diffusion through the solid was identified as the reaction-rate-controlling resistance; however, during the initial period, particularly at lower temperatures, resistance to interfacial chemical reaction was also significant, though not dominant. The apparent rate constant was observed to increase marginally with decreasing size of the particles constituting the nuggets. The apparent activation energy of reduction was estimated to be in the range from 49.640 to 51.220 kJ/mol and was not observed to be affected by the particle size. The sulfur and carbon contents in the reduced samples were also determined.

关键词： iron ore reduction coal devolatilization kinetic studies

Substrate effect on morphology and photoluminescence from ZnO monopods and bipods

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Frontiers of Optoelectronics 2011年第2期4卷 130-136页

作者： Pijus Kanti SAMANTA Partha Roy chaudhuri Department of Physics Rabindra Satabarsiki Mahavidyalaya Department of Physics & Meteorology Indian Institute of Technology Kharagpur

A simple wet chemical bath deposition has been successfully deployed to fabricate zinc oxide(ZnO)nanostructures. For substrate free growth, the nanostructure is spindle like monopods. But when the nanostructures grow on the glass and quartz substrates, they are bipods(two monopods joined together base to base). Variation in the size of the spindles of the monopods and bipods and the particle size was observed due to the strain exists in the thin film due to lattice mismatch at the interface of the thin film and the substrates. The X-ray diffraction(XRD) and selected area diffraction results confirmed the hexagonal unit cell structures of the monopods and bipods. Also the growth rates of various planes are different and the growth is anisotropic. The substrate free grown monopods show visible photoluminescence(PL) at 421 nm. But the emission gets shifted by 3 and 6 nm for ZnO thin film deposited on quartz and glass substrates respectively due to interfacial strain. In case of ZnO on quartz substrate a strong ultra-violet(UV) peak was observed at 386 nm due to band edge transition. These emissions are also accompanied by few weaker emission peaks due to various defect related transition.

关键词： monopods bipods particle-size strain photoluminescence (PL) recombination