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Water sources for typical desert vegetation in the Ebinur Lake basin

Journal of Geographical sciences 2022年第6期32卷 1103-1118页

作者： HAO Shuai LI Fadong College of Geographic science and Tourism Xinjiang Normal UniversityUrumqi 830054China Key Laboratory of xinjiang uygur autonomous region Xinjiang Laboratory of Lake Environment and Resources in Arid AreaUrumqi 830054China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China College of Resource and Environment University of Chinese Academy of SciencesBeijing 100190China

In arid and semi-arid environments,desert vegetation plays an important role in preventing soil erosion by wind and helps maintain the stability of desert and oasis *** types of typical desert vegetation,namely Populus euphratica,Haloxylon ammodendron,Nitraria sibirica,and Halostachs caspica,corresponding to different habitats(i.e.,river bank,sand dune,desert,and salt marsh)were chosen as the model vegetation in this ***δ^(2)H andδ^(18)O for rainwater,soil water,and plant water were applied to identify the water sources and quantify the proportions of different water sources used over the entire plant growth period(from March to October).The results showed that the precipitationδ^(2)H andδ^(18)O in the Ebinur Lake basin varied from-142.5‰to-0.6‰and from-20.16‰to 1.20‰,*** largestδ^(2)H andδ^(18)O values occurred in summer and the smallest in *** soil waterδ^(2)H andδ^(18)O of the four habitats decreased gradually with increasing ***δ^(2)H andδ^(18)O values of water extracted from the stems of the four plants had similar variation trends,that is,the maximum was observed in spring and the minimum in *** the four plants,*** had the highest stable isotopic values in the stem water,followed by ***,***,and *** water sources and utilization ratios of desert vegetation varied across different growth *** the growing period,*** mainly used groundwater,whereas the water source proportions used by *** varied greatly throughout the growing *** spring,plants mainly relied on surface soil water,with a contribution rate of 80%-94%.However,in summer,the proportion of deep soil water used was 31%-36%;and in autumn,the proportion of middle soil water used was 33%-36%.*** mainly relied on topsoil water in spring and autumn,and the proportion of soil water in the middle layer slightly increased to 20%-36%in *** mainly used intermediate so

关键词： desert vegetation water use stable isotopes of hydrogen and oxygen Ebinur Lake basin

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Assessment of ecological quality in Northwest China(2000-2020)using the Google Earth Engine platform:Climate factors and land use/land cover contribute to ecological quality

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Journal of Arid Land 2022年第11期14卷 1196-1211页

作者： WANG Jinjie dING Jianli GE Xiangyu QIN Shaofeng ZHANG Zhe College of Geography and Remote Sensing science Xinjiang UniversityUrumqi 800046China xinjiang Key Laboratory of Oasis Ecology Xinjiang UniversityUrumqi 830046China Key Laboratory of Smart City and Environment Modelling of Higher Education Institute Xinjiang UniversityUrumqi 830046China

The ecological quality of inland areas is an important aspect of the United Nations Sustainable development Goals(UN SdGs).The ecological environment of Northwest China is vulnerable to changes in climate and land use/land cover,and the changes in ecological quality in this arid region over the last two decades are not well *** makes it more difficult to advance the UN SdGs and develop appropriate measures at the regional *** this study,we used the Moderate Resolution Imaging Spectroradiometer(MOdIS)products to generate remote sensing ecological index(RSEI)on the Google Earth Engine(GEE)platform to examine the relationship between ecological quality and environment in xinjiang during the last two decades(from 2000 to 2020).We analyzed a 21-year time series of the trends and spatial characteristics of ecological *** further assessed the importance of different environmental factors affecting ecological quality through the random forest algorithm using data from statistical yearbooks and land use *** results show that the RSEI constructed using the GEE platform can accurately reflect the ecological quality information in xinjiang because the contribution of the first principal component was higher than 90.00%.The ecological quality in xinjiang has increased significantly over the last two decades,with the northern part of this region having a better ecological quality than the southern *** areas with slightly improved ecological quality accounted for 31.26%of the total land area of xinjiang,whereas only 3.55%of the land area was classified as having a slightly worsen(3.16%)or worsen(0.39%)ecological *** vast majority of the deterioration in ecological quality mainly occurred in the barren areas Temperature,precipitation,closed shrublands,grasslands and savannas were the top five environmental factors affecting the changes in *** factors were allocated different weights for different RSEI *** genera

关键词： ecological quality land use/land cover spatiotemporal change remote sensing ecological index(RSEI) Google Earth Engine xinjiang

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Radical cascade cyclization for the green and simple synthesis of silylated indolo[2,1-a]isoquinoline derivatives via visible light-mediated Si–H bonds activation

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Chinese Chemical Letters 2024年第1期35卷 243-249页

作者： Zhenkai Lei Fei Xue Bin Wang Shijie Wang Yu Xia Yonghong Zhang Weiwei Jin Chenjiang Liu State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources Key Laboratory of Oil and Gas Fine ChemicalsMinistry of Education&Xinjiang Uygur Autonomous RegionUrumqi Key Laboratory of Green Catalysis and Synthesis TechnologyCollege of ChemistryXinjiang UniversityUrumqi 830017China College of Future Technology Institute of Materia Medic1Xinjiang UniversityUrumqi 830017China xinjiang uygur autonomous region Product Quality Supervision and Inspection Institute Urumqi 830011China

Photocatalytic and photoinduced silyl radicals cascade cyclization procedures for the green and simple preparation of fused tetracyclic skeleton silylated indolo[2,1-a]isoquinoline-6(5H)-ones from 2-aryl-N-acryloyl indoles with hydrosilanes are *** photocatalytic reaction is carried out with 9,10-dicyanoanthracene(dCA)as an organophotocatalyst and 3-acetoxyquinuclidine as hydrogen atom transfer(HAT)catalyst at room temperature under metal-and oxidant-free *** keys to the success of photoredox-catalytic conversion include(1)the reductive quenching of dCA^(*)[E_(1/2)(*P/P^(-))=+1.97 V *** in MeCN]by 3-acetoxyquinuclidine(E_(p)=+1.22 V *** in MeCN),and(2)the thermodynamic feasibility of hydrogen atom abstraction from hydridic Si-H bond by electrophilic N^(+·).Particularly,the simple photoinduced cascade cyclization using(TMS)3SiH with 2-aryl-N-acryloyl indoles was exploited via an electron-donor-acceptor(EdA)complex under visible light irradiation.

关键词： Indolo[2,1-a]isoquinolines Silyl radicals Green photocatalytic Simple photoinduced Silylated Hydrogen atom transfer EdA complex

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Evolution of groundwater recharge-discharge balance in the Turpan Basin of China during 1959-2021

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Journal of Arid Land 2023年第9期15卷 1037-1051页

作者： QIN Guoqiang WU Bin dONG Xinguang dU Mingliang WANG Bo College of Hydraulic and Civil Engineering Xinjiang Agricultural UniversityUrumqi 830052China

Groundwater overexploitation is a serious problem in the Turpan Basin,xinjiang uygur autonomous region of China,causing groundwater level declines and ecological and environmental problems such as the desiccation of karez wells and the shrinkage of *** on historical groundwater data and field survey data from 1959 to 2021,we comprehensively studied the evolution of groundwater recharge and discharge terms in the Turpan Basin using the groundwater equilibrium method,mathematical statistics,and GIS spatial *** reasons for groundwater overexploitation were also *** results indicated that groundwater recharge increased from 14.58×10^(8)m^(3)in 1959 to 15.69×10^(8)m^(3)in 1980,then continued to decrease to 6.77×10^(8)m^(3)in *** discharge increased from 14.49×10^(8)m^(3)in 1959 to 16.02×10^(8)m^(3)in 1989,while continued to decrease to 9.97×10^(8)m^(3)in *** 1980,groundwater recharge-discharge balance has been broken,the decrease rate of groundwater recharge exceeded that of groundwater discharge and groundwater recharge was always lower than groundwater discharge,showing in a negative equilibrium,which caused the continuous decrease in groundwater level in the Turpan *** 1980 to 2002,groundwater overexploitation increased rapidly,peaking from 2003 to 2011 with an average overexploitation rate of 4.79×10^(8)m^(3)/a;then,it slowed slightly from 2012 to 2021,and the cumulative groundwater overexploitation was 99.21×10^(8)m^(3)during *** research can provide a scientific foundation for the restoration and sustainable use of groundwater in the overexploited areas of the Turpan Basin.

关键词： groundwater overexploitation groundwater recharge groundwater discharge climate change human activities Turpan Basin

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Estimation of soil organic matter in the Ogan-Kuqa River Oasis, Northwest China, based on visible and near-infrared spectroscopy and machine learning

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Journal of Arid Land 2023年第2期15卷 191-204页

作者： ZHOU Qian dING Jianli GE Xiangyu LI Ke ZHANG Zipeng GU Yongsheng College of Geography and Remote Sensing science Xinjiang UniversityUrumqi 830046China xinjiang Key Laboratory of Oasis Ecology Xinjiang UniversityUrumqi 830046China Key Laboratory of Smart City and Environment Modelling of Higher Education Institute Xinjiang UniversityUrumqi 830046China

Visible and near-infrared(vis-NIR)spectroscopy technique allows for fast and efficient determination of soil organic matter(SOM).However,a prior requirement for the vis-NIR spectroscopy technique to predict SOM is the effective removal of redundant ***,this study aims to select three wavelength selection strategies for obtaining the spectral response characteristics of *** SOM content and spectral information of 110 soil samples from the Ogan-Kuqa River Oasis were measured under laboratory conditions in July *** correlation analysis was introduced to preselect spectral wavelengths from the preprocessed spectra that passed the 0.01 level significance *** successive projection algorithm(SPA),competitive adaptive reweighted sampling(CARS),and Boruta algorithm were used to detect the optimal variables from the preselected ***,partial least squares regression(PLSR)and random forest(RF)models combined with the optimal wavelengths were applied to develop a quantitative estimation model of the SOM *** results demonstrate that the optimal variables selected were mainly located near the range of spectral absorption features(i.e.,1400.0,1900.0,and 2200.0 nm),and the CARS and Boruta algorithm also selected a few visible wavelengths located in the range of 480.0–510.0 *** models can achieve a more satisfactory prediction of the SOM content,and the RF model had better accuracy than the PLSR *** SOM content prediction model established by Boruta algorithm combined with the RF model performed best with 23 variables and the model achieved the coefficient of determination(R2)of 0.78 and the residual prediction deviation(RPd)of *** Boruta algorithm effectively removed redundant information and optimized the optimal wavelengths to improve the prediction accuracy of the estimated SOM ***,combining vis-NIR spectroscopy with machine learning to estimate SOM content is an important method to improve th

关键词： soil organic matter content vis-NIR spectroscopy random forest Boruta algorithm machine learning

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Mediating role of social support in dysphoria,despondency,and quality of life in patients undergoing maintenance hemodialysis

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World Journal of Psychiatry 2024年第3期14卷 409-420页

作者： Xiang Zhou Hong Jiang Yi-Peng Zhou Xiao-Yu Wang Hai-Yan Ren Xue-Fei Tian Qing-Qing Zhang department of Nephrology People’s Hospital of Xinjiang Uygur Autonomous RegionXinjiang Clinical Research Center for Kidney DiseaseUrumqi 832000Xinjiang Uygur Autonomous RegionChina department of Endocrinology and Metabolism People’s Hospital of Xinjiang Uygur Autonomous RegionUrumqi 832000Xinjiang Uygur Autonomous RegionChina Section of Nephrology Department of Internal MedicineYale University School of MedicineNew HavenCT 06510United States

BACKGROUNd dysphoria and despondency are prevalent psychological issues in patients undergoing Maintenance Hemodialysis(MHd)that significantly affect their quality of life(QOL).High levels of social support can significantly improve the physical and mental well-being of patients undergoing ***,there is limited research on how social support mediates the relationship between dysphoria,despondency,and overall QOL in patients undergoing *** is imperative to investigate this mediating effect to mitigate dysphoria and despondency in patients undergoing MHd,ultimately enhancing their overall *** To investigate the mediating role of social support in relationships between dysphoria,despondency,and QOL among patients undergoing *** Participants comprised 289 patients undergoing MHd,who were selected using a random sampling *** Social Support Rating Scale,Self-Rating Anxiety Scale,Self-Rating depression Scale,and QOL Scale were *** analysis was performed to examine the associations between social support,dysphoria,despondency,and QOL in patients undergoing *** assess the mediating impact of social support on dysphoria,despondency,and QOL in patients undergoing MHd,a bootstrap method was *** Significant correlations among social support,dysphoria,despondency,and quality in patients undergoing MHd were observed(all P01).dysphoria and despondency negatively correlated with social support and QOL(P01).dysphoria and despondency had negative predictive impacts on the QOL of patients undergoing MHd(Pdirect effect of dysphoria on QOL was statistically significant(Pdiated the relationship between dysphoria and QOL,and this mediating effect was significant(Pdirect effect of despondency on QOL was significant(Pd a mediating role between despondency and QOL,with a significant mediating effect(Pd

关键词： Maintenance hemodialysis Social support dysphoria despondency Quality of life Mediating effect

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Learning Sequential and Structural dependencies Between Nucleotides for RNA N6-Methyladenosine Site Identification

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2123-2134页

作者： Guodong Li Bowei Zhao Xiaorui Su dongxu Li Yue Yang Zhi Zeng Lun Hu xinjiang Technical Institute of Physics and Chemistry Chinese Academy of ScienceUrumqi 830011China College of Computer Xi’an Jiaotong UniversityXi’an 710049China IEEE

N6-methyladenosine(m6A)is an important RNA methylation modification involved in regulating diverse biological processes across multiple ***,the identification of m6A modification sites provides valuable insight into the biological mechanisms of complex diseases at the post-transcriptional *** a variety of identification algorithms have been proposed recently,most of them capture the features of m6A modification sites by focusing on the sequential dependencies of nucleotides at different positions in RNA sequences,while ignoring the structural dependencies of nucleotides in their threedimensional *** overcome this issue,we propose a cross-species end-to-end deep learning model,namely CR-NSSd,which conduct a cross-domain representation learning process integrating nucleotide structural and sequential dependencies for RNA m6A site ***,CR-NSSd first obtains the pre-coded representations of RNA sequences by incorporating the position information into single-nucleotide states with chaos game representation *** then constructs a crossdomain reconstruction encoder to learn the sequential and structural dependencies between *** minimizing the reconstruction and binary cross-entropy losses,CR-NSSd is trained to complete the task of m6A site *** experiments have demonstrated the promising performance of CR-NSSd by comparing it with several state-of-the-art m6A identification ***,the results of cross-species prediction indicate that the integration of sequential and structural dependencies allows CR-NSSd to capture general features of m6A modification sites among different species,thus improving the accuracy of cross-species identification.

关键词： Cross-domain reconstruction cross-species prediction N6-methyladenosine(m6A)modification site RNA sequence sequential and structural dependencies

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Understanding the Activity Performance of Comets 38P/Stephan-Oterma,64P/Swift-Gehrels and C/2017 M4(ATLAS)through Broadband Photometric Observations

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Research in Astronomy and Astrophysics 2024年第8期24卷 147-156页

作者： Xuan Zhang Jin-Zhong Liu Le-Tian Wang xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

In this work,we report observations of three comets:38P/Stephan-Oterma,64P/Swift-Gehrels,and C/2017 M4(ATLAS),conducted with the Nanshan one-meter wide-field telescope in 2018 August and November,and *** extracted morphological features through image enhancement techniques and calculated the dust activity parameter,Afρ,along with dust mass loss rates and coma color indices using broadband photometric *** morphological analysis uncovered a spectrum of dust characteristics among the observed comets,ranging from a significant twisted structure in comet 38P/Stephan-Oterma’s coma to the regular coma envelope surrounding comet 64P/*** Afρvalues varied between 148.8±0.3 cm for 64P/Swift-Gehrels and1118.5±6.2 cm for C/2017 M4(ATLAS)(measured within a reference aperture radius ofρ=6″),indicating a range from moderate to high activity *** mass loss rates were estimated from 328.1 kg s^(-1)for comet 64P/Swift-Gehrels to 1395.5 kg s^(-1)for comet C/2017 M4(ATLAS).The color indices of comets 38P/Stephan-Oterma and C/2017 M4(ATLAS)closely resemble the average colors of active short-period comets and active longperiod comets,*** contrast,64P/Swift-Gehrels exhibits a significantly bluer hue than typical Jupiter family comets.

关键词： comets general-comets individual(38P/Stephan-Oterma,64P/Swift-Gehrels,C/2017 M4(ATLAS))-techniques photometric

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degradable preformed particle gel as temporary plugging agent for low-temperature unconventional petroleum reservoirs:Effect of molecular weight of the cross-linking agent

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Petroleum science 2022年第6期19卷 3182-3193页

作者： Hong-Jun Zhang dao-Yi Zhu Yong-Long Gong Jun-Hui Qin Xiao-Ning Liu Yuan-Hang Pi Qi Zhao Run-Tian Luo Wan-Sheng Wang Ke-Ke Zhi Zong-Jie Mu China University of Petroleum-Beijing at Karamay KaramayXinjiang834000China

The development of unconventional petroleum resources has gradually become an important succession for increasing oil ***,the related engineers and researchers are paying more and more attention to the application of temporary plugging agents(TPAs)for their efficient *** can expand the stimulated reservoir volume(SRV)and facilitate the flow of oil and gas to the bottom of the ***-gels used as temporary plugging agents have the characteristics of the simple injection process,good deformation,high plugging strength,and complete self-degradation performance,which have been widely applied in recent *** this paper,five samples of dPPG polymerized by different molecular weights of cross-linking agents were *** addition,infrared spectroscopy analysis,differential calorimetry scanning(dSC)analysis,static particle gel swelling and degradation performance evaluation experiments,and dynamic temporary plugging performance experiments in cores were conducted at 34°*** show that as the molecular weight of the cross-linking agent(at 0.01 g)in the dPPG molecule decreased from 1,000 to 200 da,the fewer cross-linking sites of dPPG,the looser the microscopic three-dimensional mesh structure *** swelling ratio increased from 7 to 33 ***,the complete degradation time increased from 40 to 210 ***,the dSC results confirmed that the higher the molecular weight of the cross-linking agent,the worse is chemical stability and the more prone it to *** samples had good temporary plugging performance in reservoir *** prepared by the cross-linking agent with smaller molecular weight has a stronger swelling ratio,higher gel strength,and greater plugging strength in the core ***,the degraded dPPG is less damaging to the ***,their slower degradation rates take a slightly longer times to reach complete *** results of this paper can provide new ideas and

关键词： Temporary plugging agent Preformed particle gel degradable cross-linking agent Molecular weight Low-temperature reservoir

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Research on Quantitative Identification of Three-dimensional Connectivity of Fractured-Vuggy Reservoirs

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Energy Engineering 2024年第5期121卷 1195-1207页

作者： Xingliang deng Peng Cao Yintao Zhang Yuhui Zhou Xiao Luo Liang Wang Exploration and development Research Institute PetroChina Tarim Oilfield CompanyKorla841000China PetroChina Hangzhou Research Institute of Geology Hangzhou310023China School of Petroleum Engineering Yangtze UniversityWuhan430100China

The fractured-vuggy carbonate oil resources in the western basin of China are extremely *** connectivity of carbonate reservoirs is complex,and there is still a lack of clear understanding of the development and topological structure of the pore space in fractured-vuggy ***,effective prediction of fractured-vuggy reservoirs is *** view of this,this work employs adaptive point cloud technology to reproduce the shape and capture the characteristics of a fractured-vuggy *** identify the complex connectivity among pores,fractures,and vugs,a simplified one-dimensional connectivity model is established by using the meshless connection element method(CEM).Considering that different types of connection units have different flow characteristics,a sequential coupling calculation method that can efficiently calculate reservoir pressure and saturation is *** automatic history matching,the dynamic production data is fitted in real-time,and the characteristic parameters of the connection unit are *** results show that the three-dimensional connectivity model of the fractured-vuggy reservoir built in this work is as close as 90%of the fine grid model,while the dynamic simulation efficiency is much higher with good accuracy.

关键词： Fractured-vuggy reservoir three-dimensional connectivity connection unit dynamic prediction automatic history matching

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