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Journal of Arid Land 2020年第2期12卷 227-238页

作者： ZHAO Jingjing gong lu CHEN Xin College of Resources and Environment Science Xinjiang UniversityUrumqi 830046China Key Laboratory of Oasis Ecology Xinjiang UniversityUrumqi 830046China

Changes in ecological stoichiometry reflect nitrogen(N),phosphorus(P)and both N and P limitations in a plant community,which in turn affect plant diversity of the ***,the relationship between plant community diversity and ecological stoichiometry has not yet been fully researched in arid and semi-arid *** stoichiometry and plant community diversity indices of eighteen communities in the upper reaches of Tarim River,northwestern China,were analyzed by multivariate analysis of variance in *** correlation between ecological stoichiometry and plant community diversity was assessed by redundancy analysis(RDA).Results indicated that the Margalef index was significantly correlated with carbon(C)and P concentrations,the Simpson index and Shannon-Weaner index were significantly correlated with plant C concentration,and the Pielou index was significantly correlated with plant C and N ***,C:N and C:P ratios had significant impacts on plant community *** results highlight the importance of ecological stoichiometry in driving plant community diversity in the upper reaches of Tarim River,northwestern China.

关键词： Margalef index Simpson index Shannon-Weaner index redundancy analysis Tarim River

Reclamation during oasification is conducive to the accumulation of the soil organic carbon pool in arid land

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Journal of Arid Land 2023年第3期15卷 344-358页

作者： YANG Yuxin gong lu TANG Junhu College of Ecology and Environment Xinjiang UniversityUrumqi 830017China Key Laboratory of Oasis Ecology Ministry of EducationUrumqi 830017China Xinjiang Jinghe Observation and Research Station of Temperate Desert Ecosystem Ministry of EducationUrumqi 830017China

Soil organic carbon(SOC)and its stable isotope composition reflect key information about the carbon cycle in *** of carbon fractions in oasis continuous cotton-cropped fields can elucidate the SOC stability mechanism under the action of the human-land relationship during the oasification of arid land,which is critical for understanding the carbon dynamics of terrestrial ecosystems in arid lands under global climate *** this study,we investigated the Alar Reclamation Area on the northern edge of the Tarim Basin,Xinjiang Uygur Autonomous Region of China,in *** original desert and oasis farmlands with different reclamation years,including 6,10,18,and 30 a,and different soil depths(0-20,20-40,40-60 cm),we analyzed the variations in SOC,very liable carbon(C_(VL)),liable carbon(C_(L)),less liable carbon(C_(LL)),and non-liable carbon(C_(NL))using the method of spatial *** differences in the stable carbon isotope ratio(δ^(13)C)and beta(β)values reflecting the organic carbon decomposition rate were also determined during *** redundancy analysis,we derived and discussed the relationships among SOC,carbon fractions,δ^(13)C,and other soil physicochemical properties,such as the soil water content(SWC),bulk density(BD),pH,total salt(TS),total nitrogen(TN),available phosphorus(AP),and available potassium(AK).The results showed that there were significant differences in SOC and carbon fractions of oasis farmlands with different reclamation years,and the highest SOC was observed at the oasis farmland with 30-a reclamation year.C_(VL),C_(L),C_(LL),and C_(NL) showed significant changes among oasis farmlands with different reclamation years,and C_(VL) had the largest variation range(0.40-4.92 g/kg)and accounted for the largest proportion in the organic carbon *** proportion of C_(NL) in the organic carbon pool of the topsoil(0-20 cm)gradually increased.δ^(13)C varied from-25.61‰to-22.58‰,with the topsoil showing the most positive va

关键词： oasification soil organic carbon carbon fractions labile carbon δ^(13)C arid land

On f-Hypercentral Actions of Finite Group

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Communications in Mathematics and Statistics 2021年第4期9卷 521-533页

作者： Baojun Li lu gong School of Sciences Nantong UniversityNantong 226019JiangsuPeople’s Republic of China

Let f be a formation function and G an *** is said that A acts f-hypercentrally on G if A acts f-centrally on every A-composition factor of *** this paper,groups are investigated by f-hypercentral *** particular,some ... 详细信息

关键词： Finite group Formation f-hypercentral action Nilpotency

Relations between soil heterogeneity and common reed(Phragmites australis *** Steud.) colonization in the Keriya River Basin,Xinjiang of China

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Journal of Arid Land 2014年第6期6卷 753-761页

作者： lu gong ChangJun LI Tashpolat TIYIP College of Resources and Environment Science Xinjiang University Key Laboratory of Oasis Ecology Ministry of Education Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Cele National Station of Observation & Research for Desert-Grassland Ecosystem in Xinjiang

How common reed （Phragmites australis Trin. ex Steud.） colonization correlates to soil heterogeneity and environmental determinants remains unclear in arid areas. We conducted a field investigation and soil sampling in 100 plots along Keriya River Basin to uncover the relationship between common reed and heterogeneous soils. Reed colonization variables and its soil properties were measured and recorded for the analysis of their relationship using Pearson correlation and redundancy analysis methods. The comparison results of common reed characteris- tics among 100 plots showed that common reeds performed strong tolerance and ecophysiological plasticity to edaphic stresses. Common reed colonization was tightly connected to soil heterogeneity according to the correla- tion analysis between its colonization characteristics and soil properties. Common reed colonization got feedbacks on soil properties as well, including the increase of soil organic matter and the alleviation of salt uplifting. The main limiting environmental determinant of common reed colonization was soil salt, followed by pH and soil water content.

关键词： soil heterogeneity plant colonization common reed plasticity determinant

Extended Technicolor Dynamics and Single Top Quark Production at the Fermilab Tevatron

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Chinese Physics Letters 1998年第9期15卷 631-633页

作者： YUE Chong-xing lu gong-ru CCAST(World Laboratory) P.O.Box 8730Beijing 100080 and Department of Physics He’nan Normal UniversityXinxiang 453002

The large electron positron collider value of branching ratio Rb is larger than the standard model predicted value RSMb,this deviationδRb is treated as an allowed range for the correction to the single top quark production cross sectionσ(tb)arising from the extended technicolor *** is found that the relative correctionδσ(tb)/σ0(tb)is quite large for a certain range of the free parameters in the model,and may be detected in the future proton-antiproton collision experiments.

关键词： dynamics. correction Fermi

New Physics Effects on Rare Decays B_u^+→π^+■^+■^-, ρ^+■^+■-in a Top Quark Two-Higgs-Doublet Model

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Communications in Theoretical Physics 2008年第9期50卷 696-702页

作者： SONG Hai-Zhen lu Lin-Xia lu gong-Ru Department of Physics Nanyang Normal University Nanyang 473061 China Department of Physics Henan Normal University Xinxiang 453007 China

Using the form factors from light-cone sum rules, we study the branching ratios and forward-backward asymmetries （FBAs） of the exclusive decays Bu^＋→π^＋e^＋e^- and Bu^＋ →ρ^＋e^＋e^- （e= e,μ） in the standard model （SM） and the top quark two-Higgs-doublet model （T2HDM）. From the numerical results, we find that the new physics contributions cannot provide very large enhancement to the branching ratios and the theoretical predictions are in good agreement with the SM ones. The T2HDM effects on FBAs of these decays are small. Precision measurements of the dilepton invariant mass distributions, especially in the lower dilepton mass region, and the FBAs in the decays Bu^＋ → π^＋（ρ^＋）e^＋ e^- will greatly help in discriminating among the SM and the new physics models.

关键词： new physics effects rare decay two-Higgs-doublet model branching ratio forward-backward asymmetry

The Production of Pseudo Goldstone Boson in Top Quark Rare Decay

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Communications in Theoretical Physics 2002年第5期38卷 566-570页

作者： HUANG Jin-Shu lu gong-Ru Department of Physics Henan Nanyang Normal College Nanyang 473061 China Department of Physics Henan Normal University Xinxiang 453002 China

We calculate the flavor changing t → cπ0 decay in the framework of the topcolor assisted multiscaletechnicolor model. We find that (a) the branching ratio of t → cπ0 is insensitive to mπ, mπs and mπt, while it increasesquickly as ε increases; (b) for reasonable ranges of the parameters, the maximum of the branching ratio in this modelmay reach 7 × 10-6, seven orders larger compared to the one t → cH0 calculated in the standard model. This mightprovide an opportunity to detect the rare decay of the top quark in experiments.

关键词： branching ratio, rare decay of the top quark, pseudo Goldstone boson, technicolor

Stabilization of Cu/ZnO Based Catalysts by Nickel Additive in Methanol Decomposition

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Chemical Research in Chinese Universities 2001年第4期17卷 420-425页

作者： XI Jing-yu WANG Zhi-fei lu gong-xuan State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsThe Chinese Academy of SciencesLanzhou 730000P.R.China

A series of Cu/Zn based catalysts with and without Ni, prepared by the co-precipitation method, has been studied for methanol decomposition. CO and H2 are the major products. The Cu/Zn catalysts show a low initial activity and a poor stability. The formation of the CuZn alloys was observed in the deactivated Cu/Zn catalysts which were used for methanol decomposition at 250 . When small amounts of Ni were added in the catalyst, the Cu/Zn/Ni(molar ratio 5/4/ x) catalysts showed a high activity at a low temperature. The activity and the stability of the catalyst depend on the nickel content. The activity of the Cu/Zn/Ni catalysts was maintained at a. relatively stable value of 78% conversion of methanol with 95% selectivity of H2, 93% selectivity of CO, and a more than 70% yield of hydrogen was obtained at 250 C when x >1. The stability of the Cu/Zn/Ni (molar ratio 5/4/x) catalysts showed the maximum (ca 88%) when x=1. The stabilization effect of nickel on the Cu/Zn based catalysts may lead to the increasing of the dispersion of active Cu species and the prevention of CuZn alloys formation.

关键词： Nickel Cu/Zn catalysts Stabilization Methanol Decomposition

Nutrient resorption and its influencing factors of typical desert plants in different habitats on the northern margin of the Tarim Basin, China

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Journal of Arid Land 2023年第7期15卷 858-870页

作者： ZHOU Chongpeng gong lu WU Xue luO Yan College of Ecology and Environment Xinjiang UniversityUrumqi 830017China Key Laboratory of Oasis Ecology Ministry of EducationUrumqi 830017China

The resorption of nutrients from senescent leaves allows plants to conserve and recycle nutrients. To explore the adaptation strategies of desert plants to nutrient-limited environments, we selected four typical desert plants(Populus euphratica Oliv., Tamarix ramosissima Ledeb., Glycyrrhiza inflata Batal., and Alhagi camelorum Fisch.) growing in the desert area of the northern margin of the Tarim Basin,China. The contents of nitrogen(N), phosphorus(P), potassium(K), calcium(Ca), magnesium(Mg), and Ferrum(Fe) in the leaves of these four typical desert plants and their resorption characteristics were analyzed. The relationship of nutrient resorption efficiency with leaf functional traits and soil physical-chemical properties in two different habitats(saline-alkali land and sandy land) was *** results showed that the four plants resorbed most of the elements. Ca was enriched in the leaves of ***, G. inflate, and A. camelorum;Mg was enriched in the leaves of G. inflata;and Fe was enriched in the leaves of the four plants. The results of the redundancy analysis showed that leaf thickness, soil electrical conductivity, and soil P content were the major factors affecting the nutrient resorption efficiency of the four plants. Leaf thickness was negatively correlated with N resorption efficiency(NRE),P resorption efficiency, and Fe resorption efficiency;soil electrical conductivity was positively correlated with the resorption efficiency of most elements;and soil P content was negatively correlated with the resorption efficiency of most elements in the plant leaves. The results showed that soil physical-chemical properties and soil nutrient contents had an important impact on the nutrient resorption of plant *** same species growing in different habitats also differed in their resorption of different elements. The soil environment of plants and the biological characteristics of plant leaves affected the resorption of nutrient elements in different p

关键词： nutrient resorption leaf functional traits soil physical-chemical properties resorption efficiency different habitats desert plants

Synthesis and characterization of superhydrophobic magnesium oxysulfate whiskers

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Particuology 2023年第7期78卷 111-121页

作者： Zhenying Yao lu gong Chunmei Zhu Xin Lian Bai He Shenghui Tian Bo Yui School of Chemistry and Chemical Engineering Chongqing University of Science and TechnologyChongqing401331China Provincial and Ministerial Co-Constructive of Collaborative Innovation Center for MSw Comprehensive Utilization School of Metallurgy and Materials EngineeringChongqing University of Science and TechnologyChongqing401331China

Superhydrophobic materials have attracted much attention for their special *** this *** oxysulfate(MOS)whiskers were surface modified by vinyltrimethoxysilane(VTMS)and prepared as superhydrophobic materials,which are expected to be widely used in self-cleaning,corro-sion prevention,and oil-water *** factors of silane concentration,hydrolysis time,reaction temperature,and reaction time were *** superhydrophobic Mos whiskers were *** and XRD turned out that there were no apparent changes in the morphology and crystalli-zation behavior of whiskers before and after modification,while the surface was uniformly coated with a layer of non-crystal material,and the surface of the whiskers employed a chemical bond Si-O-Mg covalently *** thermogravimetric analysis ultimately demonstrated that surface modification was beneficial to the improvement of the thermal stability of MoS *** MoS whiskers showed good compatibility with organic solvents through oil-water separation experiments,and demonstrated excellent self-cleaning *** methodology for the surface treatment of Mos whiskers to prepare superhydrophobic whiskers in this work may be extended for other whiskers or fillers,which may be promising for the preparation of superhydrophobic materials.

关键词： Magnesium oxysulfate whiskers Surface modification Vinyltrimethoxysilane Superhydrophobicity