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Estimation of above-ground biomass and carbon stock of an invasive woody shrub in the subtropical deciduous forests of Doon Valley,western Himalaya,India

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Journal of Forestry Research 2015年第2期26卷 291-305页

作者： gautam Mandal S.P.Joshi Ecology Research Laboratory Department of BotanyDAV (PG) College Faculty of Science The Lawrence School

This study describes the different parameters used to derive the allometric equation for calculating the biomass of an invasive woody shrub Lantana camara *** the subtropical conditions of western *** identifies the most accurate and convenient method for biomass calculation by comparing destructive with nondestructive *** parameters were measured on a wide range of Lantana from different community levels for the non-destructive calculation of total aboveground *** explanatory variables were identified and measured such as basal diameter either as a single independent variable or in combination with plant *** other suitable combinations of available independent variables include crown length,crown width,crown area,crown volume and coverage of the *** the wide range of allometric equations used with different variables,the equation with D2 H as a variable was found to be the most suitable estimator of biomass calculation for ***,being the most disturbed area due to its high tourist activity round the year,showed maximum coverage（58.57 % ha-1）,highest biomass（13,559.60 kg ha-1） and carbon density（6,373.01 kg ha-1）of *** degree of Lantana’s invasiveness in subtropical conditions was also calculated on the basis of importance value index（IVI）.The maximum IVI（22.77）and mean coverage（26.8 % ha-1） was obtained from the areas near Jolly Grant airport,indicating that physically disturbed areas are more suitable for the growth of Lantana,which may significantly increase shrub *** importance of incorporating allometric equations in calculation of shrub biomass,and its role in atmospheric carbon assimilation has thus been highlighted through the findings of this study.

关键词： Above ground carbon pools Allometric regression equations Carbon density Importance value index(IVI) Shrub biomass

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Effect of disturbance on biomass,production and carbon dynamics in moist tropical forest of eastern Nepal

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Forest Ecosystems 2016年第3期3卷 221-230页

作者： Tilak Prasad gautam Tej Narayan Mandal Department of Botany Mahendra Morang Adarsha Multiple CampusTribhuvan University Department of Botany Post Graduate Campus Tribhuvan University

Background： Forest biomass is helpful to assess its productivity and carbon （C） sequestration capacity. Several disturbance activities in tropical forests have reduced the biomass and net primary production （NPP） leading to climate change. Therefore, an accurateestimation of forest biomass and C cycling in context of disturbances is required for implementing REDD （Reducing Emissions from Deforestation and Forest Degradation） policy. Methods： Biomass and NPP of trees and shrubs were estimated by using allometric equations while herbaceous biomass was estimated by harvest method. Fine root biomass was determined from soil monolith. The C stock in vegetation was calculated by multiplying C concentration to dry weight. Results： Total stand biomass （***-1） in undisturbed forest stand （US） was 960.4 while in disturbed forest stand （DS） it was 449.1. The biomass （***-1） of trees, shrubs and herbs in US was 948.0, 4.4 and 1.4, respectively, while in DS they were 438.4, 6.1 and 1.2, respectively. Total NPP （***-1） was 26.58 （equivalent to 12.26 Mg ***-1） in US and 14.91 （6.88 Mg ***-1） in DS. Total C input into soil through litter plus root turnover was 6.78 and 3.35 ***-1 in US and DS, respectively. Conclusions： Several disturbance activities resulted in the significant loss in stand biomass （53 %）, NPP （44 %）, and C sequestration capacity of tropical forest vegetation is far greater than that returned to the soil n eastern Nepal. The net uptake of carbon by the by the turnover of fine root and litter. Therefore, both stands of present forest act as carbon accumulating systems. Moreover, disturbance reflects higher C emissions which can be reduced by better management.

关键词： Tropical forest Disturbance Biomass Production Carbon cycling Nepa

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One-dimensional ZnS-based Hetero-,Core/shell and Hierarchical Nanostructures

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Journal of Materials Science & Technology 2008年第4期24卷 520-528页

作者： Ujjal K.gautam Yoshio BANDO Dmitri GOLBERG Nanoscale World Premier International Center for Materials Nanoarchitectonics and Nanoscale Materials Center National Institute for Materials ScienceNamiki 1-1TsukbaIbaraki 305-0044Japan

A focus of the current nanotechnology has shifted from routine fabrication of nanostructures to designing functional electronic devices and realizing their immense potentials for applications. Due to infusion of multi-functionality into a single system, the utilization of hetero-, core/shell and hierarchical nanostructures has become the key issue for building such devices. ZnS, due to its direct wide bandgap, high index of refraction, high transparency in the visible range and intrinsic polarity, is one of the most useful semiconductors for a wide range of electronics applications. This article provides a dense review of the state-of-the-art research activities in one-dimensional （1D） ZnS-based hetero-, core/shell and hierarchical nanostructures. The particular emphasis is put on their syntheses and applications.

关键词： Heterostructures Core/shell Hierarchical structures ZnS Nanodevices

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Search for periodicities of the solar irradiance data from the Earth Radiation Budget Satellite (ERBS) using the periodogram method

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Research in Astronomy and Astrophysics 2010年第4期10卷 348-354页

作者： Sankar Narayan Patra gautam Bhattacharya Koushik Ghosh Department of Applied Electronics and Instrumentation Engineering University Institute of Technologythe University of Burdwan Department of Physics University Institute of Technologythe University of Burdwan Department of Mathematics University Institute of Technologythe University of Burdwan

We have analyzed the solar irradiance data from the Earth Radiation Budget Satellite （ERBS） during the time period from 1984 October 15 to 2003 October *** first filtering the data by Simple Exponential Smoothing,we have applied the periodogram method to the processed data in order to search for its time *** study exhibits multi-periodicities on these data around 110,118,574 and 740d with very high confidence levels （more than 99%）.These periods are significantly similar to the periods of other solar activities which may suggest that solar irradiance may be associated with other solar activities.

关键词： Sun:activity - Sun:fundamental parameters

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Friction and wear behavior of Cu-4 wt.％Ni-TiC composites under dry sliding conditions

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Friction 2017年第4期5卷 437-446页

作者： Pushkar JHA Rakesh Kumar gautam Rajnesh TYAGI Department of Mechanical Engineering Indian Institute of Technology(Banaras Hindu University)Varanasi 221005India

The present study synthesized Cu–4 wt% Ni matrix composites reinforced with different percentages of TiC (0, 2, 4, 6, and 8 wt%) through high-energy ball milling, followed by compaction and sintering. The friction and wear behavior was examined at four different normal loads of 5, 10, 15, and 20 N. A constant sliding speed of 1.25 m/s was maintained while sliding against a hardened counterface made of EN31 steel (HRC 60) under ambient conditions using a pin-on-disk test rig. The composite hardness increased until the addition of 4 wt% of TiC, beyond which it was observed to decrease. Such a trend may be attributed to the TiC agglomeration in the composites containing relatively larger amounts of TiC (i.e., 6 and 8 wt%). The wear rate linearly increased with the load. However, the composites exhibited a lower rate of wear than the matrix alloy, which may have resulted from the relatively higher hardness of composites. The observed friction and wear behavior has been explained on the basis of hardness and presence of the transfer layer on the worn surface and its nature, i.e., loose or well compacted. Addition of 4 wt% TiC showed the optimum performance in terms of friction and wear caused by its higher hardness and ability to hold a transfer layer of a relatively larger thickness compared to the other materials. The wear mechanism for the Cu4Ni matrix alloy was a mix of adhesive and oxidative wear and primarily abrasive for the composites containing hard TiC particles.

关键词： sliding wear composites TiC particles friction

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口服氨甲环酸、外用维生素C、维生素E联合IPL治疗黄褐斑的疗效观察

口服氨甲环酸、外用维生素C、维生素E联合IPL治疗黄褐斑的疗效观察

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作者： Madhab gautam 湖北医药学院

学位级别：硕士

背景:黄褐斑是一种常见的、慢性的、获得性、局限性色素增多或色素沉着性皮肤病,也被称为“肝斑”。它表现为对称分布的不规则锯齿状或地图状的色素沉着。这种色素沉着影响着世界上数百万人,且女性比男性更容易出现黄褐斑。由于黄褐斑... 详细信息

背景:黄褐斑是一种常见的、慢性的、获得性、局限性色素增多或色素沉着性皮肤病,也被称为“肝斑”。它表现为对称分布的不规则锯齿状或地图状的色素沉着。这种色素沉着影响着世界上数百万人,且女性比男性更容易出现黄褐斑。由于黄褐斑具有难治性和复发性,因此其治疗效果欠佳。我们通过观察比较口服氨甲环酸、外用维生素C、外用维生素E联合(Intense pulsed light,IPL)治疗在黄褐斑中的疗效,为黄褐斑的治疗提供更效的治疗方法。目的:通过比较和评价口服氨甲环酸、外用维生素C、外用维生素E联合强脉冲光治疗黄褐斑12周的疗效和安全性,为黄褐斑的治疗提供更有效的治疗手段。材料与方法:本研究选取了2018年2月至2019年12月在湖北医药学院附属在国药东风总医院皮肤科就诊的99例黄褐斑患者。本研究从99例患者的病例记录和治疗记录中提取数据。患者选入采用纳入和排除标准。变量是人口统计数据,如年龄和性别。入选标准:确诊黄褐斑患者;年龄在25-45岁。治疗前后色素沉着改善程度评分如下:0、色素沉着加重,无变化;2、病情轻(病灶清除率75%)。结果:研究发现黄褐斑的高发年龄是在25-40岁之间,平均年龄为32.5岁,范围在25-45岁之间。所有患者均定期随访并进行MSI评分。研究表明,少数患者在接受治疗后黄褐斑出现好转;IPL的治疗时间从40分钟到120分钟不等,平均治疗时间为60分钟;患者就医时间从2小时到4小时不等,平均就医时间为3小时。3例患者黄褐斑出现反复(5%)。治疗前黄褐斑患者的平均MSI评分为7.96±1.26,1年后平均MSI评分为2.52±0.81。治疗前的平均评分系统(MSI)为3.26±1.41,1年后随访平均评分系统(MSI)为8.26±1.17。随访患者3个月和1年,82.12%的患者MSI评分为良好或显著,且通过改良的Mac nab评分法,89.3%的患者黄褐斑的改善为良好或显著。结论:IPL、外用维生素C、维生素E、口服氨甲环酸联合治疗效果更佳。

关键词：黄褐斑治疗氨甲环酸维生素C 维生素E IPL

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Prophylactic Effect of Gossypin Against Percutaneously Administered Sulfur Mustard

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Biomedical and Environmental Sciences 2007年第3期20卷 250-259页

作者： ANSHOO gautam R.VIJAYARAGHAVAN Defence Research and Development Establishment Gwalior-474002India

Objective To evaluate the protective efficacy of gossypin （3,3＇,4＇,5,7,8-hexahydroxyflavone 8-glucoside） by administering it intraperitoneally, for dose, time, and vehicle dependent effects against sulphur mustard （SM）, administered through percutaneous route in mice. Methods SM （diluted in PEG-300） was administered percutaneously. The protective efficacy of gossypin was evaluated by administering it intraperitoneally （50, 100, 200, and 400 mg/kg）, in various vehicles （water, PEG-300 and DMSO）, and time intervals （30 min prior, simultaneous and 2 h post）. The time dependent protection of gossypin （200 mg/kg in PEG-300; i.p.） was also evaluated using selected biochemical variables （GSH, GSSG, MDA, total antioxidant status, Hb, WBC count, RBC count, glutathione peroxidase, glutathione reductase, and superoxide dismutase） and liver histology. The protection of gossypin by oral route was also evaluated against percutaneously administered SM. Results The protection against systemic toxicity of SM （LD50 8.1 mg/kg） was better when gossypin was given with PEG-300 （8.0 folds） than DMSO （5.7 folds）. No protection was observed when gossypin was administered with water. Good protection （8.0 folds） was observed when gossypin was administered （200 mg/kg in PEG-300; i.p.） at 30 min prior or simultaneous to SM exposure, but no protection was observed when gossypin was administered 2 h post to SM exposure. A significant weight loss was observed 7 days after SM administration （2 LD50）, with a significant increase in RBC and Hb. A significant decrease in total antioxidant status of plasma, liver GSH and GSSG levels, and in the activities of glutathione peroxidase, glutathione reductase and superoxide dismutase was also observed 7 days after SM administration. SM treated mouse liver also showed necrosis. A significant protection was observed when gossypin （200 mg/kg in PEG-300; i.p.） was administered either as a pretreatment （30 min before） or simultaneous treatment, and not as a post

关键词： Sulfur mustard Gossypin Oxidative stress Glutathione Intraperitoneal Oral

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Effect of operating parameters on coal gasification

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International Journal of Coal Science & Technology 2018年第2期5卷 113-125页

作者： Akanksha Mishra Shalini gautam Tripurari Sharma Department of Mechanical Engineering Sharda UniversityGreater Noida India Department of Fuel and Mineral Engineering Indian Institute of Technology (Indian School of Mines) Dhanbad India

Coal combustion and gasification are the processes to utilize coal for production of electricity and many other applications. Global energy demand is increasing day by day. Coal is an abundant source of energy but not a reliable source as it results into high CO2 emissions. Energy industries are expected to decrease the CO2 emission to prevent global warming. Coal gasification is a process that reduces the CO2 emission and emerges as a clean coal technology. Coal gasification process is regulated by several operating parameters. A Number of investigations have been carried out in this direction. A critical review of the work done by several researchers in the field of coal gasification has been compiled in this paper. The effect of several operating parameters such as coal rank, temperature, pressure, porosity, reaction time and catalyst on gasification has been presented here.

关键词：煤燃烧气化能源行业煤炭

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Simplified theoretical analysis and numerical study on the dynamic behavior of FCP under blast loads

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Frontiers of Structural and Civil Engineering 2020年第4期14卷 983-997页

作者： Chunfeng ZHAO Xin YE Avinash gautam Xin LU YLMO Anhui Key Laboratory of Civil Engineering Structures and Materials Hefei University of TechnologyHefei 230009China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024.China School of Civil Engineering Hefei University of TechnologyHefei 230009China Deparment of Civil and Environmental Enginering University of HoustonHoustonTX 77024USA

Precast concrete structures have developed rapidly in the last decades due to the advantages of better quality,non-pollution and fast construction with respect to conventional cast-in-place *** the present study,a theoretical model and nonlinear 3D model are developed and established to assess the dynamic behavior of precast concrete slabs under blast *** first,the 3D model is validated by an experiment performed by other *** verified model is adopted to investigate the blast performance of fabricated concrete panels(FCPs)in terms of parameters of the explosive charge,panel thickness,and reinforcement ***,a simplified theoretical model of the FCP under blast load is developed to predict the maximum *** is indicated that the theoretical model can precisely predict the maximum displacement of FCP under blast *** results show that the failure modes of the panels varied from bending failure to shear failure with the mass of TNT *** thickness of the panel,reinforcement ratio,and explosive charges have significant effects on the anti-blast capacity of the FCPs.

关键词： precast structure fabricated concrete panel blast resistance theory model empirical equation

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Hydrogen sulfide,nitric oxide,and neurodegenerative disorders

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Translational Neurodegeneration 2018年第1期7卷 16-23页

作者： Sandesh Panthi Sumeet Manandhar Kripa gautam Otago School of Biomedical Sciences University of OtagoDunedinNew Zealand Department of Pharmacy Chosun UniversityGwangjuSouth Korea China Medical University ShenyangPeople’s Republic of China

Hydrogen Sulfide(H_(2)S)and Nitric Oxide(NO)have become recognized as important gaseous signaling molecules with enormous pharmacological effects,therapeutic value,and central physiological *** is one of the most important regulators of the pathophysiological condition in central nervous system(CNS).It is critical in the various functioning of the brain;however,beyond certain concentration/level,it is toxic.H_(2)S was regarded as toxic gas with the smell like rotten ***,it is now regarded as emerging neuroprotectant and ***,the use of donors and inhibitors of these signaling molecules have helped us to identify their accurate and precise biological *** most abundant neurotransmitter of CNS(glutamate)is the initiator of the reaction that forms NO,and H_(2)S is highly expressed in *** molecules are shedding light on the pathogenesis of various neurological *** review is mainly focused on the importance of H_(2)S and NO for normal functioning of CNS.

关键词： Hydrogen sulfide Nitric oxide Central nervous system Gasotransmitters Gaseous signaling molecules Neurodegeneration Neurodegenerative disorders

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