检索结果-南通市图书馆

Simulating Alpine Vegetation Net Primary Productivity by Remote Sensing in Qinghai Province,China

Journal of Mountain Science 2014年第4期11卷 967-978页

作者： WEI Ya-xing wang li-wen Center for Marine Economic and Sustainable Development Liaoning Normal University liaoning Key Laboratory of Physical Geography and Geomatics Liaoning Normal University College of Urban and Environmental Science Liaoning Normal University

Primary productivity of ecosystem is important indicator about ecological assessment. Remote sensing technology has been used to monitor net primary productivity （NPP） of ecological system for several years. In this paper, the remotely sensed NPP simulation model of alpine vegetation in Qinghai Province of Tibet Plateau was set up based on the theory of light use efficiency. Firstly a new approach based on mixed pixels and Support Vector Machine （SVM） algorithm were used to correct simulated NPP values derived from Moderate Resolution Imaging Spectroradiometer （MODIS） data. Finally, spatial distribution and monthly variation characteristics of NPP in Qinghai Province detail. The result showed in 2006 were analyzed in that NPP of vegetation in Qinghai Province in 2006 ranged from o to 422 gC/m2/a and the average NPP was 151 gC/m2/a. NPP gradually increased from northwest to southeast. NPP of different vegetation types were obviously different. The average NPP of broad-leaved forest was the largest （314 gC/m2/a）, and sparse shrub was the smallest （101 gC/m2/a）. NPP in Qinghai Province significantly changed with seasonal variation. The accumulation of NPP was primarily in the period （from April to September） with better moist and heat conditions. In July, the average NPP of vegetation reached the maximum value （43 gC/m2）. In our model, the advantage of traditional LUE models was adopted, and our study fully considered typicalcharacteristics of alpine vegetation light use efficiency and environmental factors in the study area. Alpine vegetation is the most important ecological resource of Tibet Plateau, exactly monitoring its NPP value by remote sensing is an effective protection measure.

关键词： Net primary productivity Remotesensing light use efficiency model Contexturalapproach Support Vector Machine

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Formation mechanism of an aluminium-based chemical conversion coating on AZ91D magnesium alloy

引用

International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 641-647页

作者： Wei-ping li Xi-mei wang li-qun Zhu wen li Key Laboratory of Aerospace Materials and Performance （Ministry of Education of China） School of Materials Science and EngineeringBeihang University Beijing 100083 China

An environmentally clean aluminium-based conversion coating on AZ91D magnesium alloy was studied in aluminium nitrate solutions. The morphology, composition, structure, and formation mechanism of the coating were investigated in detail using scanning electron microscopy/energy dispersion spectrometry, X-ray diffraction, transmission electron microscopy, and electrochemical corrosion tests. The results show that the conversion coating is composed of magnesium, aluminium, and oxygen, and shows an amorphous structure. In the initial stage of coating formation, the grain-like nucleus is composed of Al10O15·xH2O, （Al2O3）5.333, Al2O3, AlO（OH）, MgAl2O4, （Mg0.88Al0.12）（Al0.94Mg0.06）2O4, and （Mg0.68Al0.32）（Al0.84Mg0.16）2O4. The conversion coating formed in the 0.01 mol/L aluminium nitrate solution for 15 min can improve the corrosion resistance of the magnesium alloy greatly. The discussion reveals that the possible formation mechanism for the aluminium-based conversion coating is the reduction reaction on micro-cathodic sites due to the electrochemically heterogeneous magnesium alloy substrate.

关键词： magnesium alloys coatings aluminium nitrate corrosion resistance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of polar cortical cytoskeleton and unbalanced cortical surface tension on intercellular bridge thinning during cytokinesis

引用

Acta Mechanica Sinica 2011年第6期27卷 1081-1090页

作者： li wang Mei-wen An Xiao-Na li Fang Yang Yang liu Institute of Applied Mechanics and Biomedical Engineering Taiyuan University of Technology 030024 Taiyuan China

To probe the contributions of polar cortical cytoskeleton and the surface tension of daughter cells to intercellular bridge thinning dynamics during cytokinesis,we applied cytochalasin D（CD） or colchicine（COLC） in a highly localized manner to polar regions of dividing normal rat kidney（NRK） *** observed cellular morphological changes and analyzed the intercellular bridge thinning trajectories of dividing cells with different polar cortical *** blebbistatin（BS） application was used to obtain cells losing active contractile force *** results show that locally released CD or colchicine at the polar region caused inhibition of cytokinesis before *** treatment at phases after ingression allowed completion of cytokinesis but dramatically influenced the trajectories of intercellular bridge *** single polar cortical actin induced transformation of the intercellular bridge thinning process,and polar cortical tension controlled deformation time of intercellular *** study provides a feasible framework to induce and analyze the effects of local changes in mechanical properties of cellular components on single cellular cytokinesis.

关键词： Cytokinesis Normal rat kidney epithelial cells Intercellular bridge Polar cortical cytoskeleton - Cortical surface tension

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Modulation Transfer Spectroscopy of Ytterbium Atoms in a Hollow Cathode Lamp

引用

Chinese Physics Letters 2011年第3期28卷 55-57页

作者： wang wen-li XU Xin-Ye State Key Laboratory of Precision Spectroscopy and Department of Physics East China Normal UniversityShanghai 200062

We present the experimental study of modulation transfer spectroscopy of ytterbium atoms in a hollow cathode *** dependences of its linewidth,slope and magnitude on the various experimental parameters are measured and fitted by the well-known theoretical *** experimental results are in good agreement with the theoretical *** have observed the Dicke narrowing effect by increasing the current of the hollow cathode *** is also found that there are the optimal current and laser power to generate the better modulation transfer spectroscopy signal,which can be employed for locking the laser frequency to the atomic transition.

关键词： transition laser Dicke

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Genetic analysis of adult plant,quantitative resistance to stripe rust in wheat landrace Wudubaijian in multi-environment trials

引用

Journal of Integrative Agriculture 2022年第8期21卷 2305-2318页

作者： CHAO Kai-xiang WU Cai-juan li Juan wang wen-li wang Bao-tong li Qiang State Key Laboratory of Crop Stress Biology for Arid Areas College of Plant ProtectionNorthwest A&F UniversityYangling 712100P.R.China College of Chemistry Biology and Environment Yuxi Normal UniversityYuxi 653100P.R.China

Stripe rust,caused by Puccinia striiformis ***(Pst),is one of the most destructive diseases on wheat ***,a wheat landrace released from Gansu Province in China since 1950,exhibits adult-plant resistance to stripe rust for several *** elucidate the genetic basis of stripe rust resistance,Wudubaijian was crossed with the high susceptible cultivar Mingxian 169,and stripe rust tests of both parents and the F2:3 lines were conducted in four environments of Yangling and Tianshui in 2015 and 2016,*** relative area under disease progress curve(rAUDPC)of Mingxian 169/Wudubaijian F_(2:3) lines showed that the resistance of Wudubaijian was controlled by quantitative trait loci(QTL).Combined with phenotypic data and molecular markers,two stable QTLs were identified in ***-5A with the phenotypic variance of 15.02-40.26% was located between 5AS1-0.40-0.75 and 5AS3-0.75-0.98 of chromosome 5AS,and ***-2B.1 with the phenotypic variance of 9.54-10.40%was located in the bin C-2BS1-0.53 of chromosome *** the location of flanking markers and epistasis analysis,***-5A may be a new major QTL that can be used in conjunction with other stripe rust resistance genes(QTLs).

关键词： Triticum aestivum Puccinia striiformis f.sp.tritici adult-plant resistance QTL mapping

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Precipitation Kinetics of Cr_2N in High Nitrogen Austenitic Stainless Steel

引用

Journal of Iron and Steel Research International 2008年第6期15卷 72-77页

作者： SHI Feng wang li-jun CUI wen-fang liU Chun-ming School of Materials and Metallurgy Northeastern University Shenyang 110004 Liaoning China

The precipitation behavior of Cr2 N during isothermal aging in the temperature range from 700 ℃ to 950 ℃ in Fe-18Cr-12Mn-0.48N （in mass percent） high nitrogen austenitic stainless steel, including morphology and content of precipitate, was investigated using optical microscopy, scanning electron microscopy, and transmission electron microscopy. The isothermal precipitation kinetics curve of Cr2 N and the corresponding precipitation activation energy were obtained. The results show that Cr2N phase precipitates in a cellular way and its morphology is transformed from initial granular precipitates to lamellar ones in the cell with increasing aging time. The nose temperature of Cr2 N precipitation is about 800 ℃, with a corresponding incubation period of 30 min, and the ceiling temperature of Cr2N precipitation is 950℃. The diffusionactivation energy of Cr2 N precipitation is 296 kJ/mol.

关键词： high nitrogen austenitic stainless steel isothermal aging precipitation kinetics precipitation activation energy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Preliminary Research on Cd^(2+) Removal from Wastewater by Sphaerotilus Natans

引用

Chemical Research in Chinese Universities 2005年第6期21卷 654-657页

作者： QIN Yu-chun GUAN Xiao-hui YIN Rong wang li-wen WEI De-zhou School of Resources and Civil Engineering Northeastern University Shenyang 110004 P. R. China Department of Applied Chemistry Northeast Institute of Electric Power Engineering Jilin 132012 P. R. China Department of Common Courses Beihua University Jilin 132011 P. R. China

Influencing factors, such as the biomass concentration, pH value, temperature and time of adsorption on the removal of Cd^2＋ were investigated when Sphaerotilus natans was used as a biosorbent. The results show that Sphaerotilus natans has a significant effect on the adsorption of Cd^2＋. The process of adsorption will reach the equilibrium in 20 min. Temperature has no significant effect on the adsorption. The removal rate of Cd^2＋. can approach to 90% under the conditions of pH 5.5, the biomass mass concentration O. 6 g/L and the initial mass concentration of cadmium ≤20 mg/L. The maximum specific uptake is 1.9 mmol/g dry biomass . The adsorption was fitted with the Freundlich isotherm adsorption equation when the concentration of Cd^2＋ is in a range of 0--100 mg/L. HCl and EDTA can desorb Cd^2＋ from biomass effectively.

关键词： Sphaerotilus natans Cadmium ion Adsorption character Influencing factor

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Phenanthroline-based Fluorescent Chemosensor for Selective Detection of Zn^(2+) in DMF Buffer Solution

引用

Chemical Research in Chinese Universities 2010年第6期26卷 884-887页

作者： wang Xlu-li ZHENG wen-yan liN Hong-yan liU Guo-cheng Faculty of Chemistry and Chemical Engineering Key Laboratory of Applied Chemistry of Liaoning Province Bohai University Jinzhou 121000 P. R. China

A simple ＂off-on＂ fluorescent chemosensor with high selectivity to zinc ions based on 1,10-phenanthro-line receptor dipyrido[3,2-d：2＇,3＇-f]quinoxaline（L） was *** selectivity response of receptor L to zinc ion was demonstrated by UV-Vis absorption and fluorescence spectroscopies in DMF buffer *** experiment results show that the fluorescent chemosensor L exhibits the optimum response behavior to Zn2＋ in the range of pH 8.0―9.0 and shows excellent selectivity to Zn2＋ over other cations tested.

关键词： Fluorescence Chemosensor Phenanthroline-based Cation detection selectivity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Curcumin,a Potential Inhibitor of Up-regulation of TNF-alpha and IL-6 Induced by Palmitate in 3T3-L1 Adipocytes through NF-kappaB and JNK Pathway

引用

Biomedical and Environmental Sciences 2009年第1期22卷 32-39页

作者： SHAO-liNG wang YING li YING wen YAN-FENG CHEN li-XIN NA SONG-TAO li CHANG-HAO SUN Department of Nutrition and Food Hygiene Harbin Medical University No. 157 Baojian Road Harbin 150081 Heilongjiang China

Objective To investigate the attenuating effect of curcumin, an anti-inflammatory compound derived from dietary spice turmeric （Curcuma longa） on the pro-inflammatory insulin-resistant state in 3T3-L1 adipocytes. Methods Glucose uptake rate was determined with the [3H] 2-deoxyglucose uptake method. Expressions of tumor necrosis factor-α （TNF-α） and interleukin-6 （IL-6） were measured by quantitative RT-PCR analysis and EliSA. Nuclear transcription factor kappaB p65 （NF-r,B p65） and mitogen-activated protein kinase （MAPKs） were detected by Western blot assay. Results The basal glucose uptake was not altered, and curcumin increased the insulin-stimulated glucose uptake in 3T3-L1 cells. Curcumin suppressed the transcription and secretion of TNF-α and IL-6 induced by palmitate in a concentration-dependent manner. Palmitate induced nuclear translocation of NF-kB. The activities of Jun NH2-terminal kinase ONK）, extracellular signal-regulated kinasel/2 （ERKI/2） and p38MAPK decreased in the presence of curcumin. Moreover, pretreatment with SP600125 （inhibitor of JNK） instead of PD98059 or SB203580 （inhibitor of ERKI/2 or p38MAPK, respectively） decreased the up-regulation of TNF-α induced by palmitate. Conelusion Curcumin reverses palmitate-induced insulin resistance state in 3T3-L1 adipocytes through the NF-kB and JNK pathway.

关键词： Curcumin Insulin resistance Inflammation Adipocyte Free fatty acids

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

An Algorithm for Detecting Ice Cloud at Different Altitudes by Combining Dual CrIS Full Spectrum Resolution CO2 Channels

引用

Journal of Tropical Meteorology 2020年第3期26卷 300-310页

作者： wang li-wen ZHENG You-fei TIAN Miao XU Jing-xin Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science&TechnologyNanjing 210044 China Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science&TechnologyNanjing 210044China Information Engineering Department School of Information and Communication EngineeringUniversity of Electronic Science and Technology of ChinaChengdu 611731 China State Environmental Protection Key Laboratory of Atmospheric Physical Modeling and Pollution Control State Power Environmental Protection Research InstituteNanjing 210031 China

Using infrared sensors to detect ice clouds in different atmospheric layers is still a *** different scattering and absorption properties of longwave and shortwave infrared channels can be utilized to fulfill this *** this study,the release of Suomi-NPP Cross-track Infrared Sounder(Cr IS)full spectrum resolution is used to select and pair channels from longwave(~15μm)and shortwave(~4.3μm)CO2 absorption bands under stricter conditions,so as to better detect ice ***,the differences of the weighting function peaks and cloud insensitive level altitudes of the paired channels are both within 50 h Pa so that the variances due to atmospheric conditions can be *** training data of clear sky are determined by Visible Infrared Imaging Radiometer Suite(VIIRS)cloud mask product and used to find the linear relationship between the paired longwave and shortwave CO2 absorption *** the linear relationship,the so-called cloud emission and scattering index(CESI)is derived to detect ice *** clearly captures the center and the ice cloud features of the Super Typhoon Hato located above 415 h ***,the CESI distributions agree with cloud top pressure from the VIIRS in both daytime and nighttime in different atmospheric layers.

关键词： Cross-track Infrared Sounder Full Spectral Resolution(CrIS FSR) ice cloud detection dual CO2 absorption bands

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：