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A dynamic model for exploring water-resource management scenarios in an inland arid area: Shanshan County, Northwestern China

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Journal of Mountain Science 2017年第6期14卷 1039-1057页

作者： CHEN Chao ahmad sajjad KALRA Ajay XU Zhi-xia Department of Civil and Environmental Engineering and Construction University of Nevada Department of Civil and Environmental Engineering Southern Illinois University Department of Water Resources China Institute of Water Resources and Hydropower Research

Water scarcity is a challenge in many arid and semi-arid regions; this may lead to a series of environmental problems and could be stressed even further by the effects from climate change. This study focused on the water resource management in Shanshan County, an inland arid region located in northwestern China with a long history of groundwater overexploitation. A model of the supply and demand system in the study area from 2006 to2030, including effects from global climate change,was developed using a system dynamics(SD)modeling tool. This SD model was used to 1) explore the best water-resource management options by testing system responses under various scenarios and2) identify the principal factors affecting the responses, aiming for a balance of the groundwater system and sustainable socio-economic *** causes were identified as primarily responsible for water issues in Shanshan: low water-use efficiency low water reuse, and increase in industrial waterdemand. To address these causes, a combined scenario was designed and simulated, which was able to keep the water deficiency under 5% by 2030. The model provided some insights into the dynamic interrelations that generate system behavior and the key factors in the system that govern water demand and supply. The model as well as the study results may be useful in water resources management in Shanshan and may be applied, with appropriate modifications, to other regions facing similar water management challenges.

关键词：水资源管理内陆干旱区中国西北部动态模型鄯善县系统动力学气候变化影响全球气候变化

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黄沙坪铅锌多金属矿床岩浆岩石英斑晶的结构与地球化学组成

黄沙坪铅锌多金属矿床岩浆岩石英斑晶的结构与地球化学组成

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作者： sajjad ahmad Shah（撒加达）中南大学

学位级别：硕士

黄沙坪矽卡岩型W-Mo-Cu多金属矿床是南岭中部地区重要的矿床,其储量为74.31 Mt W-Mo(WO 0.28%,Mo 0.07%),20.35 Mt Cu(Cu 1.12%)。该矿床以发育与石英斑岩有关的Cu成矿系统和与花岗斑岩有关的W-Mo矽卡岩成矿系统为特征。矿区除发育成矿... 详细信息

黄沙坪矽卡岩型W-Mo-Cu多金属矿床是南岭中部地区重要的矿床,其储量为74.31 Mt W-Mo(WO 0.28%,Mo 0.07%),20.35 Mt Cu(Cu 1.12%)。该矿床以发育与石英斑岩有关的Cu成矿系统和与花岗斑岩有关的W-Mo矽卡岩成矿系统为特征。矿区除发育成矿岩体花岗斑岩和石英斑岩外,还发育不成矿岩体英安斑岩和正长斑岩。前人对该矿床的研究已相当丰富,但由于黄沙坪岩浆岩蚀变强烈,其成因还缺乏有效的制约。本文重点研究了黄沙坪岩浆岩石英斑晶的阴极发光(CL)内部结构和微量元素地球化学特征。碎裂结构、扰动的震荡环带、缺少斜长石斑晶表明石英斑岩形成深度较深,其上升就位的速度较快;而花岗斑岩石英斑晶具有均一的内部结构,揭示其岩浆在较稳定的条件下缓慢上升。此外,这些致矿花岗岩石英斑晶具有较低的Ti/Al比值(0.05-0.10),表明其具有过铝质(Al>Na+K+Ca、斜长石比例增加)、更酸性(高Al含量)和较低的温度等性质;而无矿的花岗岩具有高Ti/Al比值(0.3),表明其具有偏铝质(Al

关键词：微量元素内部结构花岗岩石英斑晶黄沙坪

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Using Path Analysis to Identify the Influence of Climatic Factors on Spring Peak Flow Dominated by Snowmelt in an Alpine Watershed

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Journal of Mountain Science 2014年第4期11卷 990-1000页

作者： ZHANG Fei-Yun LI Lan-Hai ahmad sajjad LI Xue-Mei State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Graduate School University of Chinese Academy of Sciences Department of Civil and Environmental Engineering University of Nevada Las Vegas NV 89154-4015 USA Faculty of Geomatics Lanzhou Jiaotong University

Spring snowmelt peak flow(SSPF) can cause serious damage. Precipitation as rainfall directly contributes to the SSPF and influences the characteristics of the SSPF, while temperature indirectly impacts the SSPF by shaping snowmelt rate and determining the soil frozen state which partitions snowmelt water into surface runoff and soil infiltration water in spring. It is necessary to identify the important and significant paths of climatic factors influencing the SSPF and provide estimates of the magnitude and significance of hypothesized causal connections between climatic factors and the *** study used path analysis with a selection of five factors – the antecedent precipitation index(API),spring precipitation(SP), winter precipitation as snowfall(WS), 0°C temperature accumulation in spring(AT) – to analyze their influences on the SSPF in the Kaidu River in Xinjiang,China. The results show that |ATN|, AT and WS have a significant correlation with the SSPF, while API and SP do not show a significant correlation. AT and WS directly influence the SSPF, while as the influence of |ATN| on SSPF is indirect through WS and AT. The indirect influence of |ATN| on SSPF through WS accounts for 69% of the total influence of |ATN| on SSPF. Compared to the multiple linear regression method, path analysis provides additional valuable information, including influencing paths from independent variables to the dependent variable as well as direct and indirect impacts of external variables on the internal variable. This information can help improve the description of snow melt and spring runoff in hydrologic models as well as the planning and management of water resources.

关键词：路径分析融雪速度气候因素高峰流量多元线性回归方法流域高山春运

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Drought Forecasting in a Semi-arid Watershed Using Climate Signals:a Neuro-fuzzy Modeling Approach

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Journal of Mountain Science 2014年第6期11卷 1593-1605页

作者： Bahram CHOUBIN Shahram KHALIGHI-SIGAROODI Arash MALEKIAN sajjad ahmad Pedram ATTAROD Department of Watershed Management Sari University of Agriculture Sciences and Natural ResourcesSari 48181-68984Iran University of Tehran Faculty of Natural ResourcesKaraj 31585-3314 Iran Department of Civil and Environmental Engineering University of NevadaLas Vegas NV 89154-4015 USA

Large-scale annual climate indices were used to forecast annual drought conditions in the Maharlu-Bakhtegan watershed,located in Iran,using a neuro-fuzzy *** Standardized Precipitation Index(SPI) was used as a proxy for drought *** the 45 climate indices considered,eight identified as most relevant were the Atlantic Multidecadal Oscillation(AMO),Atlantic Meridional Mode(AMM),the Bivariate ENSO Time series(BEST),the East Central Tropical Pacific Surface Temperature(NINO 3.4),the Central Tropical Pacific Surface Temperature(NINO 4),the North Tropical Atlantic Index(NTA),the Southern Oscillation Index(SOI),and the Tropical Northern Atlantic Index(TNA).These indices accounted for 81% of the variance in the Principal Components Analysis(PCA) *** Atlantic surface temperature(SST:Atlantic) had an inverse relationship with SPI,and the AMM index had the highest *** forecasts of neuro-fuzzy model demonstrate better prediction at a two-year lag compared to a stepwise regression model.

关键词：神经模糊模型半干旱流域干旱预测气候指数模糊建模方法热带大西洋南方涛动指数热带太平洋

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Molecular mechanism of different viruses associated with autoimmunity

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Life Research 2022年第1期5卷 9-19页

作者： Arslan Habib Zeeshan Ashraf Irfan Ullah khan Amjad Ali Dominic Kwesi Quainoo sajjad ahmad Qamar Umutumwa Eric Principe Dur E Maknoon Razia Laboratory of Molecular Immunology School of Life SciencesFudan UniversityShanghaiChina Department of Fisheries and Aquaculture University of Veterinary&Animal SciencesLahorePakistan Centre of Biotechnology and Microbiology Faculty of Life SciencesUniversity of PeshawarPakistan Department of Biotechnology Faculty of BiosciencesUniversity for Development StudiesGhana Department of Zoology University of OkaraOkaraPakistan School of Biotechnology East China University of Science&TechnologyShanghaiChina Department of Biochemistry Government College University FaisalabadPakistan

Different kinds of human chronic diseases may develop the mechanism of autoimmune *** a group of disorders,in the Western world autoimmunity possess as the third most prevalent morbidity and ***,the mechanism of most autoimmune diseases is still under *** infection is the principal factor involved in the induction of autoimmune diseases other than genetic factors and cytokine *** mechanisms have been proposed by which viral infection might interrupt tolerance to self and induce autoimmune cascade which eventually leads to the destruction of a specific type of cell or a whole-body *** autoimmune attack can be understood through the different immune systems and other possible mechanisms such as molecular mimicry,bystander activation and epitope *** addition to genetic and viral factors,other environmental factors are also involved including bacterial,parasitic and fungal ***,different animal models have been studied which provide strong evidence that viruses induced AIDs as well as accelerated and increased lesions in conditions where self-tolerance is *** the current review,we discussed the virus-induced autoimmunity and the molecular mechanism which is associated with this *** we also discussed the different viruses such as rubella virus,enteroviruses,measles virus,human T-lymphotropic virus type1,human cytomegalovirus,human herpes virus-6,Epstein-Barr virus,rotavirus and some other viruses which modulate the development of AIDs.

关键词： autoimmunity viruses immune tolerance molecular mechanism

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Genetic diversity and population structure of Pisum sativum accessions for marker-trait association of lipid content

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The Crop Journal 2015年第3期3卷 238-245页

作者： sajjad ahmad Simerjeet Kaur Neil Dylan Lamb-Palmer Mark Lefsrud Jaswinder Singh Department of Plant Science Mc Gill University Ste Anne de Bellevue Quebec H9X 3V9 Canada Department of Bioresource Engineering Mc Gill University Ste Anne de Bellevue Quebec H9X 3V9 Canada

Field pea(Pisum sativum L.) is an important protein-rich pulse crop produced globally. Increasing the lipid content of Pisum seeds through conventional and contemporary molecular breeding tools may bring added value to the crop. However, knowledge about genetic diversity and lipid content in field pea is limited. An understanding of genetic diversity and population structure in diverse germplasm is important and a prerequisite for genetic dissection of complex characteristics and marker-trait associations. Fifty polymorphic microsatellite markers detecting a total of 207 alleles were used to obtain information on genetic diversity, population structure and marker-trait associations. Cluster analysis was performed using UPGMA to construct a dendrogram from a pairwise similarity matrix. Pea genotypes were divided into five major clusters. A model-based population structure analysis divided the pea accessions into four groups. Percentage lipid content in 35 diverse pea accessions was used to find potential associations with the SSR markers. Markers AD73, D21, and AA5 were significantly associated with lipid content using a mixed linear model(MLM) taking population structure(Q) and relative kinship(K) into account. The results of this preliminary study suggested that the population could be used for marker-trait association mapping studies.

关键词： Diversity Field Pea Lipid content Marker-trait association Mixed linear model SSR

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Assessment of Metals Concentration and Ecotoxicology of the Sediment Core of Rehri Creek, Karachi Coast, Pakistan

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Acta Geologica Sinica(English Edition) 2013年第5期87卷 1434-1443页

作者： Muhammad Z. CHAUDHARY Nasir ahmad Azhar MASHIATULLAH sajjad MUNIR Tariq JAVED Isotope Application Division Pakistan Institute of Nuclear Science and Technology (PINSTECH) Institute of Geology University of the Punjab Department of Earth & Environmental Sciences Bahria University Islamanad

Trace metal concentrations were investigated in a recent sediment core collected from the Rehri Creek area of the Karachi coast, Sindh - Pakistan. The core was sliced horizontally at 2.5-cm intervals to determine grain size, sediment composition, pH, organic matter, and acid-leachable trace metals： cadmium, chromium, copper, lead, and zinc. The trace metals were analyzed by ICP. To separate anthropogenic from geogenic input, several approaches were made, including comparison with sediment quality guidelines--ecotoxicological sense of heavy metal contamination and classification by quantitative indexes. Grain-size analysis and sediment composition of core sample show a sandy nature with neutral pH. Elemental sequence （ES） of the trace metals is in the order of Zn （19.2-109.56 ppm）〉 Si （66.46-101.71 ppm）〉 Ba （12.05-26.86 ppm）〉 As （8.18-17.36 ppm）〉 Ni （4.2- 14.69 ppm）〉 Cr （3.02-9.62 ppm）〉 Pb （2.79-6.83 ppm）〉 Cu （2.2-5.29 ppm）〉 Co （0.9-2.05 ppm）. Thus it is likely that the area may face a serious threat of metal pollution with the present deposition rates unless stringent pollution control norms are adopted. The Sediment Geo-accumulation Index shows that there is no Cr, Cu, Ni, Pb, Zn, or Fe pollution; however, the former index and the Pollution Load Index indicate arsenic pollution in the sediments.

关键词： trace elements lake sedimentation sediment quality guidelines pollution shale values

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Synthesis of a New Class of Highly Functionalized Phosphorus Ylides Containing Heterocyclic Compounds

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Chinese Journal of Chemistry 2012年第8期30卷 1893-1900页

作者： Shaabani ahmad Keshipour sajjad Aghaei Morteza Khodabandeh M. Hassan Zahedi Mansour Department of Chemistry Shahid Beheshti University G. C. P. O. Box 19396-4716 Tehran Iran

The zwitterionic intermediate generated from the reaction of triphenylphosphine with electron deficient acety- lenic compounds was trapped by various NH acids. The synthesis resulted in a new class of highly functionalized heterocyclic compounds. Some of the reactions produced E and Z isomers. And the stability and transformation of them were studied by dynamic 1H NMR and density functional theory （DFT） calculations.

关键词： highly functionalized heterocyclic compounds phosphorus ylides triphenylphosphine DFT dynamic 1H NMR

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Formamidinium-incorporated Dion-Jacobson phase 2D perovskites for highly efficient and stable photovoltaics

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Journal of Energy Chemistry 2021年第6期30卷 632-638,I0015页

作者： sajjad ahmad Wei Yu Ruixue Lu Yang Liu Tonggang Jiu Shuping Pang Xin Guo Can Li State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian National Laboratory for Clean EnergyDalian 116023LiaoningChina Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101ShandongChina University of Chinese Academy of Sciences Beijing 100049China Department of Chemistry Fudan UniversityShanghai 200438China

Dion-Jacobson phase two-dimensional(DJ 2D)perovskites,recently attracting considerable interests,exhibit excellent environmental stability and structural tunability,but their solar cells still offer unsatisfactory power conversion efficiencies(PCEs).Herein,we develop DJ 2D perovskites employing formamidinium(FA+)as a ternary cation in the perovskite cages((PDA)(FA)x(MA)3-xPb4 I13,χ=0,0.15,0.3 and 0.6,PDA=1,3-propanediammonium)for highly efficient and stable perovskite solar cells(PSCs).We found that the DJ 2D perovskite with a 10%FA+fraction presents improved crystallinity,preferred vertical orientation,and longer charge carrier lifetime compared to that without FA+*** a result,the FAdoped DJ 2D PSCs exhibit a champion PCE of 14.74%with superior device *** unencapsulated devices sustain over 92%of its initial PCE after storage at a constant relative humidity(RH)of 65%for 6000 h,90%by heat at 85℃in air for 800 h,and 94%under 1-sun illumination for 5000 *** findings demonstrate that the incorporation of FA cation into the DJ 2D perovskite is a promising strategy to develop highly efficient and stable DJ 2D PSCs.

关键词： Dion-Jacobson 2D perovskites Perovskite solar cells Formamidinium doping Power conversion efficiency

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Saponins and solvent extracts from Atriplex laciniata L. exhibited high anthelmintic and insecticidal activities

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Journal of Traditional Chinese Medicine 2017年第5期37卷 599-606页

作者： Zul Kamal Farhat Ullah sajjad ahmad Muhammad Ayaz Abdul Sadiq Muhammad Imran Shujat ahmad Faiz Ur Rahman Anwar Zeb Department of Pharmacy Shaheed Benazir Bhutto University Sheringal Dir Upper 18050Pakistan Department of Pharmacy University of Malakand Chakdara Dir Lower 18000 Pakistan Department of Zoology Shaheed Benazir Bhutto University Sheringal Dir Upper 18050 Pakistan

OBJECTIVE: To investigate saponins and various solvent extracts from Atriplex laciniata(A. laciniata)against human parasites and various ***: The samples from A. laciniata used in the activities were crude saponins(*** F) and solvent samples including methanolic extract(*** F), ethyl acetate(*** F), choloroform(*** F),n-hexane(*** F) and water residual(*** F). Anthelmintic potentials of the samples were analyzed against Pheretima posthuma(earthworms) and Ascaridia galli(round worms) using contact toxicity method. Insecticidal activities were performed against Heterotermes indicola(termite), Monomorium pharaonis(pharaoh ant), Tribolium castaneum(flour beetle) and Rhyzopertha dominica(grain borer) using standard ***: In anthelmintic assay, *** F and *** F were most effective against P. posthuma and A. gal-li with average death times of 25.62 and 29.65 min respectively. Likewise the anthelmintic assay, *** F and *** F were most effective against H. indicola causing 90.36% and 73.24% lethality respectively. Furthermore, in anti-Pharaoh activity *** F, *** F, *** F, *** F and *** F exhibited highest activity with LD50 of 78, 220, 260, 330 and > 800 mg/m L respectively. *** F and *** F were highly effective against R. dominica causing 80.11% and71.30% lethality respectively. *** F was found most active against T. ***: Our findings suggest that the *** F, *** F and *** F extracted from *** *** be the best options for the isolation of anthelmintic and bio-insecticidal compounds.

关键词： Saponins Atriplex 寄生虫 Heterotermes indicola Monomorium pharaonis Rhyzopertha dominica Tribolium castaneum

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