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Advances in Biological Chemistry 2019年第1期9卷 1-22页

作者： subarna karmaker Farin Sintaha Tapan Kumar Saha Department of Chemistry Jahangirnagar University Savar Bangladesh

The adsorption of reactive red 239 (RR239) dye onto chitosan 8B was studied in aqueous solution at various pHs, initial dye concentrations, ionic strengths and temperatures, respectively. The adsorption of dye onto chitosan 8B was confirmed by diffuse reflectance electronic absorption spectra. The adsorption of RR239 onto chitosan 8B was greatly influenced by solution pHs, initial dye concentrations, ionic strengths and temperatures. The kinetics and mechanism of dye adsorption process were analyzed by pseudo first-, second-order, Elovich and intraparticle diffusion kinetic models. The adsorption kinetics of RR239 dye followed a pseudo second-order model very well. The surface sorption and intraparticle diffusion mechanisms were involved in the actual sorption process. The equilibrium isotherm data were fitted well with the Langmuir model rather than the Freundlich, Temkin and Dubinin-Radushkevich models. The maximum dye adsorption onto chitosan 8B was estimated to be 163.93 μmol/g at 45°C. The activation energy (Ea) was obtained to be 23.30 kJ/mol. The computed thermodynamic parameters such as ΔG, ΔH, ΔS, ΔG, ΔH and ΔS confirmed that the adsorption of RR239 dye onto chitosan 8B was a spontaneous endothermic physisorption process. Desorption test was carried out in NaOH solution (pH 12.5) and the chitosan flakes could be reused.

关键词： Chitosan Reactive Red 239 Adsorption Kinetics Mechanism Thermodynamics

Antioxidant,antimicrobial,cytotoxic and analgesic activities of ethanolic extract of Mentha arvensis L.

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Asian Pacific Journal of Tropical Biomedicine 2014年第10期4卷 792-797页

作者： Nripendra Nath Biswas subarna Saha Mohammed khadem Ali School of Chemistry University of New South WalesNSW-2052SydneyAustralia Pharmacy Discipline Life science schoolKhulna University Khulna-9208Bangladesh Department of Biotechnology and Genetic Engineering Life Science SchoolKhulna-UniversityKhulna-9208Bangladesh

Objective:To investigate potential antioxidant,antimicrobial,cytotoxic and analgesic activities of ethanolic extract of Mentha arrensis l.,in different in vivo and in vitro experimental ***:In vitro DPPH radical scavenging assay was used to evaluate the antioxidant activity of the plant *** vivo analgesic activity was carried out by acetic acid—induced writhing test in Swiss albino *** studies in mice were undertaken at the doses of 250 and 500 mg/kg body *** activilv was studied by disk diffusion assay against some Gram—positive and Gram—negative bacterial *** shrimp lethality assay was used to investigate cyloloxicity effects of the plant ***:The extract showed free radical scavenging activity in the DPPH assay(IC5041 μg/mL)compared to the standard antioxidant ascorbic acid(IC5019 μg/mL).The extract also produced prominent antimicrobial activity against Salmonella *** *** boydii,Streptococcus pyogenes and Streptococcus aureus compared to standard drug kanamycin at the dose of 30 μg/*** extract exhibited lethality against the brine shrimp nauplii with the LC50,values of 40 μg/*** also 90%mortality(LC90) value was found to be 160 μg/*** analgesic *** extract demonstrated statistically significant（P<0.01） analgesic effect in acetic acid induced writhing in white albino mice al both dose ***:These results suggest that the ethanolic extract of Mentha arvenns *** potential antioxidant,antibacterial,cytotoxic and analgesic activities that support the ethnopharmacological uses of this plant.

关键词： Antioxidant Antibacterial Cytotoxic Analgesic Mentha arvensis L.

A New Species of the Genus Tylototriton(Amphibia: Urodela: Salamandridae) from Eastern Himalaya

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Asian Herpetological Research 2015年第4期6卷 245-256页

作者： Janak Raj KHATIWADA Bin WANG subarna GHIMIRE Karthikeyan VASUDEVAN Shanta PAUDEL Jianping JIANG Chengdu Institute of Biology Chinese Academy of Sciences University of Chinese Academy of Sciences Tribhuvan University Central Department of Zoology CSIR-Centre for Cellular and Molecular Biology (CCMB) Laboratory for the Conservation of Endangered Species Himalayan Research and Conservation Nepal

A new species of the genus Tylototriton is described from eastern Himalaya based on molecular and morphological comparisons. The new species is diagnosable from the closely-related species by having light brown colouration in dorsal region in life, flat and blunt snout, greatly separated dorsolateral bony ridges on head and straightthick tailfin. In addition to head morphology, the new species is also morphologically distinguishable from its closelyrelated species Tylototriton shanorum by having 16 dorsal warts and average smaller Snout Vent Length（SVL）.

关键词： Tylototriton himalayanus sp. nov. eastern Himalaya morphology molecular phylogeny taxonomy

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

Stereoconvergent and stepwise 1,3-dipolar cycloadditions of nitrile oxides and nitrile imines

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Chinese Chemical Letters 2022年第6期33卷 3012-3016页

作者： Zhenni Zhao Zhi Ou subarna Jyoti Kalita Feng Cheng Qian Huang Yangyi Gu Yuhao Wang Yan Zhao Yiyong Huang Department of Chemistry School of ChemistryChemical Engineering and Life ScienceWuhan University of TechnologyWuhan 430070China State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China

The first example of stereoconvergent 1,3-dipolar cycloaddition of nitrile oxides and nitrile imines with E/Z isomeric mixture of electron-deficient olefins is reported,delivering isoxazolines and pyrazolines bearing two vicinal stereogenic tertiary and trifluoromethylated quaternary carbon centers with perfect regioand *** possibility of concerted cycloaddition/epimerization sequence under basic condition to form the thermodynamically stable diastereomers is excluded through some control experiments and DFT calculations,and a stepwise mechanism is proposed.

关键词： Stereoconvergent 1,3-Dipolar cycloaddition Isoxazoline Pyrazoline Trifluoromethyl

Stereodivergent catalytic asymmetric allylic alkylation(AAA)

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Science Bulletin 2020年第22期65卷 1865-1868,M0003页

作者： subarna Jyoti Kalita Yi-Yong Huang Uwe Schneider Department of Chemistry School of ChemistryChemical Engineering and Life ScienceWuhan University of TechnologyWuhan 430070China EaStCHEM School of Chemistry The University of EdinburghEdinburgh EH93FJUK

Chirality or handedness,i.e.,the non-superimposability of a structure(lacking a plane or center of symmetry)with its mirrorimage,strongly impacts various chemistry/biology areas,and plays an important role,e.g.,in materials chemistry[1].In medicinal chemistry it is critical to evaluate the therapeutic and toxicological properties of all stereoisomers of a drug molecule because diastereoisomers and enantiomers may exhibit distinct biological and pharmacological activities[2].

关键词：烯丙基化反应 isomers 发散型

Evaluation of Drought Tolerant Rice Cultivars Using Drought Tolerant Indices under Water Stress and Irrigated Condition

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American Journal of Climate Change 2019年第2期8卷 228-236页

作者： Mandeep Adhikari Nav Raj Adhikari subarna Sharma Janmajaya Gairhe Rishi Ram Bhandari Sakshi Paudel Department of Plant Breeding Institute of Agriculture and Animal Science Tribhuvan University Kirtipur Nepal Department of Biological Sciences Mississippi State University Starkville Mississippi State USA Department of Soil Science and Agri-Engineering Institute of Agriculture and Animal Science Tribhuvan University Kirtipur Nepal Department of Entomology and Plant Pathology Auburn University Auburn Alabama USA Prithu Technical College Institute of Agriculture and Animal Science Tribhuvan University Dang Nepal

Drought is the most critical abiotic factor reducing rice yield in rainfed and drought prone areas. Majority of rice cultivated area in south Asia are under rainfed, where water stress at any of the critical growth stage causes sharp decline in yield. Research was conducted in western Nepal at farmers field around the close vicinity of Regional Agriculture Research Center (RARS) Nepalgunj. Ten different rice cultivars were evaluated under drought stress and non-stress condition during the year 2017 to identify superior stress tolerant cultivars. Different drought tolerance indices like stress tolerance (TOL), Stress tolerance index (STI), Stress susceptibility index (SSI), were tested in screening superior rice cultivars. Significant reduction in mean grain yield was observed under drought stress in all rice cultivars under the study. The rice cultivars with high STI values and low TOL and SSI were identified as superior drought tolerant cultivars. Based on results of different tolerance indices, Sukha series of rice, Sukha Dhan 1-6 and Radha-4 showed low TOL and SSI and high STI values and were identified as drought tolerant cultivars. The present study reveals that selection based on drought tolerance indices can be an efficient tool in identification of superior drought tolerant cultivars with higher yield and stability.

关键词： Rice Drought Stress Drought Tolerance Indices Drought Tolerant Cultivars

Sb_(2)Te_(3)/graphite nanocomposite: A comprehensive study of thermal conductivity

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Journal of Materiomics 2021年第3期7卷 545-555页

作者： subarna Das P.Singha V.A.Kulbachinskii V.G.Kytin Gangadhar Das S.Janaky A.K.Deb Sudip Mukherjee A.Maignan S.Hebert R.Daou Chandrabhas Narayana S.Bandyopadhyay Aritra Banerjee Department of Physics University of Calcutta92 A P C RoadKolkata700009India Laboratoire de Cristallographie et Sciences des Materiaux(CRISMAT) Normandie UniversiteUMR6508 CNRSENSICAENUNICAEN14000CaenFrance Department of Low Temperature Physics and Superconductivity Physics FacultyM.V.Lomonosov Moscow State University119991MoscowRussia Moscow Institute of Physics and Technology 141700DolgoprudnyMoscow RegionRussia Chemistry and Physics of Materials Unit Jawaharlal Nehru Centre for Advanced Scientific ResearchJakkur P.OBangalore560064India Department of Physics Raiganj UniversityUttar DinajpurWest Bengal733134India UGC-DAE Consortium for Scientific Research Mumbai CentreR-5 ShedBARC CampusTrombayMumbai400008India Center for Research in Nanoscience and Nanotechnology University of CalcuttaJD-2Sector-IIISaltlakeKolkata700106India

Thermoelectric performance largely depends on the reduction of lattice thermal conductivity(kL).The study of the thermal conductivity(k)of a Sb_(2)Te_(3)/graphite nanocomposite system demonstrates-40%reduction in kL with graphite incorporation.A plausible explanation of intrinsic low kL observed in Sb_(2)Te_(3) based system is presented by modeling experimental specific heat(Cp)*** spectroscopy measurement combined to X-Ray diffraction data confirms the presence of graphite as separate phase in the composite *** is found that phonon scattering dominates heat transport mechanism in the nanostructured Sb_(2)Te_(3)/graphite *** reduction in kL is accomplished by intensifying scattering rate of phonons via various *** introduces effective scattering sources,i.e.,defects of different dimensionalities in synthesized nanocomposite ***,graphite mediates phonon-phonon coupling and enhances lattice anharmonicity,which causes an intrinsic scattering of phonons with all frequencies in the Sb_(2)Te_(3)/graphite nanocomposite *** density and phonon anharmonicity of the synthesized samples are estimated from in depth analysis of temperature dependent synchrotron powder diffraction and Raman spectroscopic *** value as low as 0.8 W m1 K1 at 300 K,achieved with graphite dispersion in Sb_(2)Te_(3) based composite system makes the present comprehensive study an interesting concept to be developed in thermoelectric materials.

关键词： Thermoelectric systems Thermal conductivity Phonons X-ray powder diffraction Raman spectroscopy Specific heat measurements

痉挛性马蹄内翻足的交通隧道腱-骨附着胫后肌转移术

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中国矫形外科杂志 2022年第3期30卷 260-263页

作者：杜良杰任群榜刘宏炜李军刘永 subarna DANGOL 首都医科大学康复医学院北京博爱医院脊柱脊髓神经功能重建科北京100068 扶沟老年康复护理院河南扶沟461300

[目的]介绍隧道交通腱-骨锚定肌腱转移技术及其对痉挛性马蹄内翻足的初步临床结果.[方法]对20例痉挛性马蹄内翻足患者,行选择性胫神经肌支切断,并将胫后肌转移到骰骨或第三楔骨.在骨上制作相互交通的一个中央隧道和三个周围隧道,引入缝... 详细信息

[目的]介绍隧道交通腱-骨锚定肌腱转移技术及其对痉挛性马蹄内翻足的初步临床结果.[方法]对20例痉挛性马蹄内翻足患者,行选择性胫神经肌支切断,并将胫后肌转移到骰骨或第三楔骨.在骨上制作相互交通的一个中央隧道和三个周围隧道,引入缝线并与肌腱末端缝合,将肌腱缝合固定在中央隧道内,缝合线末端在周围隧道外两两打结固定.术后随访半年,评定肌腱与骨愈合情况,踝关节屈伸活动度范围,Holden步行能力和6 min距离.[结果]胫后肌转移后愈合率为100%.所有患者马蹄内翻畸形均消失,行走功能明显改善.与术前相比,术后6个月小腿三头肌肌张力MAS评分、踝关节屈伸活动范围(range of motion,ROM),6 min步行距离和Holden步行能力评分均显著改善(P<0.05).[结论]此隧道交通腱-骨固定胫后肌转移方法安全可靠,可有效矫正患肢马蹄内翻畸形,改善下肢负重行走功能.

关键词：痉挛性马蹄内翻足周围神经肌支选择性切断术胫后肌转移腱-骨固定

孕期妇女补充微量元素对子代6～8岁时代谢综合症指征的影响

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孕期妇女补充微量元素对子代6～8岁时代谢综合症指征的影响