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Spatial distribution and formation mechanism of aeolian sand in the middle reaches of the Yarlung Zangbo River

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Journal of Mountain Science 2019年第9期16卷 1987-2000页

作者： LIU Yong WANG Yun-sheng shen Tong State Key Lab. of Geo-Hazard Prevention and Geo-Environment Protection Chengdu University of Technology Chengdu China Institute of Exploration Technology Chinese Academy of Geological Sciences Chengdu China

Aeolian sand landforms in the Yarlung Zangbo River(YZR) valley are a special type of aeolian landform that has attracted the attention of many scholars. However, the spatial distribution as well as the formation mechanism of aeolian sand has rarely been reported with integrated studies. In this paper, for remote sensing interpretation, scanning electron microscopy(SEM), X-ray diffraction(XRD) and particle size distribution(PSD) methods were used to analyze the spatial distribution and the deposition characteristics of aeolian sand. Combined with wind data and topography, the main driving factors and the formation mechanism of aeolian sand landforms were also examined. In the middle reaches of the YZR valley, there is a total of 2324.43 km^2 of aeolian sand, especially on the north bank of the wide valleys. In different wide valleys, the aeolian sand landforms exhibit a decreasing trend from the upstream to the downstream regions in both the area and expansion rate of aeolian sand. The cyclonic vortexes generated by the westerly winds and glacial winds are the main driving factors for transporting alluvial sand to the riverbank areas to form aeolian dunes. There are three main types of sand dunes in the river valley: climbing dunes, lee dunes and circumfluent dunes. Climbing dunes and lee dunes are mostly located west of the Jiacha Gorge, and the circumfluent dunes are mostly located east of the Jiacha Gorge.

关键词： Aeolian processes Remote sensing interpretation Scanning electron microscopy X-ray diffraction Particle size distribution Glacial winds Cyclonic vortexes

Transarterial chemoembolization failure/refractoriness: A scientific concept or pseudo-proposition

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World Journal of Gastrointestinal Surgery 2022年第6期14卷 528-537页

作者： shen zhang Bin-Yan Zhong Lei zhang Wan-sheng Wang Cai-Fang Ni Department of Interventional Radiology The First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina

Multi-session transarterial chemoembolization(TACE)is usually needed for the treatment of intermediate-stage hepatocellular carcinoma(HCC),but it may not always have a positive influence on prognosis due to high heterogeneity of *** avoid ineffective repeated TACE,the concept of TACE failure/refractoriness has been proposed by several organizations and is being addressed using tyrosine kinase *** concept of TACE failure/refractoriness is controversial due to ambiguous definitions and low evidence-based *** date,only a few studies have examined the rationality concerning the definition of TACE failure/refractoriness,although the concept has been introduced and applied in many TACE-related clinical *** review focuses on some of the issues related to different versions of TACE failure/refractoriness,the rationality of related definitions,and the feasibility of continuing TACE after so-called failure/refractoriness based on published evidence.A suggestion to re-define TAEC failure/refractoriness is also put forward.

关键词： Hepatocellular carcinoma Transarterial chemoembolization Failure Refractoriness

Strong Convergence Theorems for Strictly Asymptotically Pseudocontractive Mappings in Hilbert Spaces

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Acta Mathematica Sinica,English Series 2011年第7期27卷 1367-1378页

作者： Shi sheng zhang Department of Mathematics Yibin University Yibin 644007 P. R. China

The purpose of this paper is by using CSQ method to study the strong convergence problem of iterative sequences for a pair of strictly asymptotically pseudocontractive mappings to approximate a common fixed point in a Hilbert space. Under suitable conditions some strong convergence theorems are proved. The results presented in the paper are new which extend and improve some recent results of Acedo and Xu [Iterative methods for strict pseudo-contractions in Hilbert spaces. Nonlinear Anal., 67（7）, 2258-2271 （2007）], Kim and Xu [Strong convergence of modified Mann iterations for asymptoti- cally nonexpansive mappings and semigroups. Nonlinear Anal., 64, 1140-1152 （2006）], Martinez-Yanes and Xu [Strong convergence of the CQ method for fixed point iteration processes. Nonlinear Anal., 64, 2400-2411 （2006）], Nakajo and Takahashi pings and nonexpansive semigroups. J. Math [Strong convergence theorems for nonexpansive map- Anal. Appl., 279, 372-379 （2003）], Marino and Xu [Weak and strong convergence theorems for strict pseudocontractions in Hilbert spaces. J. Math. Anal. Appl., 329（1）, 336-346 （2007）], Osilike et al. [Demiclosedness principle and convergence theorems for k-strictly asymptotically pseudocontractive maps. J. Math. Anal. Appl., 326, 1334-1345 （2007）], Liu [Convergence theorems of the sequence of iterates for asymptotically demicontractive and hemicontractive mappings. Nonlinear Anal., 26（11）, 1835-1842 （1996）], Osilike et al. [Fixed points of demi-contractive mappings in arbitrary Banach spaces. Panamer Math. J., 12（2）, 77-88 （2002）], Gu [The new composite implicit iteration process strictly pseudocontractive mappings. J. Math with errors for common fixed points of a finite family of Anal. Appl., 329, 766-776 （2007）].

关键词： Strictly asymptotically pseudocontractive mapping strictly pseudocontractive mapping of Browder Petryshyn type CSQ methods common fixed point

Water quality, agriculture and food safety in China:Current situation, trends, interdependencies, and management

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Journal of Integrative Agriculture 2015年第11期14卷 2365-2379页

作者： zhang Xiao-nan GUO Qiu-ping shen Xiao-xue YU sheng-wen QIU Guo-yu shenzhen Engineering Laboratory for Water Desalinization with Renewable Energy School of Environment and EnergyPeking University Chinese Academy for Environmental Planning

Water quality in China is becoming a severe challenge for agriculture and food safety, and it might also impact health of population via agriculture and food. Thus, it is causing widespread concern. Based on extensive literatures review and data mining, current situation of water pollution in China and its effects on food safety were analyzed. The 2nd National Water Resource Survey in China show that the surface water all over the country was under slight pollution and about 60% of groundwater is polluted. Drinking water quality is basically guaranteed in urban area but it is worrisome in rural areas. In addition, China is the largest consumer of fertilizer and pesticide in the world and the amounts of application still show increasing trends. Fertilizers and pesticides are the most important sources of pollution, which affect human health as persistent organic pollutants and environmental endocrine disruptors. Eutrophication of surface water and nitrate pollution of groundwater are serious threats to drinking water safety. Sewage irrigation is becoming a pollution source to China＇s water and land because of lacking of effective regulations. Although, with the advance in technology and management level, control of nitrogen and phosphorus emissions and reducing water pollution is still a major challenge for China.

关键词： agriculture drinking water eutrophication fertilizer food safety groundwater heavy metals microcystin nitrate pesticide pollution water quality

Effects of host （Boettcherisca peregrina） copper exposure on development, reproduction and vitellogenesis of the ectoparasitic wasp, Nasonia vitripennis

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Insect Science 2009年第1期16卷 43-50页

作者： Gong-Yin Ye sheng-zhang Dong Hui Dong Cui Hu Zhi-Cheng shen Jia-An Cheng State Key Laboratory of Rice Biology Institute of Insect Sciences Zhejiang University Hangzhou China

Effects of copper （Cu） accumulation by the flesh fly Boettcherisca peregrina （R.- D.）（Diptera： Sarcophagidae） on the ectoparasitic wasp Nasonia vitripennis （Walker）（Hymenoptera： Pteromalidae） were investigated experimentally by exposing host larvae to contaminated diets with final Cu concentrations of 400μg/g and 800μg/g diet fresh weight （DFW）, respectively. Results showed that Cu can be transferred along food chains to secondary consumers （parasitoids） in small amounts, resulting in negative effects on parasitoid growth and development （body weight and developmental duration） as well as fecundity （number of offspring per female）. Copper exposure also inhibited vitellogenesis ofparasitoids from Cu-contaminated host pupae. It is suggested that the decreased fecundity and inhibition of vitellogenesis ofN. vitripennis resulted from poor host nutritional state rather than from direct effects of Cu stress.

关键词： Boettcherisca peregrina copper fecundity Nasonia vitripennis vitellogenesis

On Lawson's Area-minimizing Hypercones

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Acta Mathematica Sinica,English Series 2016年第12期32卷 1465-1476页

作者： Yong sheng zhang School of Mathematics and Statistics Northeast Normal University

We show the area-minimality property of all homogeneous area-minimizing hypercones in Euclidean spaces （classified by Lawlor） following Lawson＇s original idea in his 72＇ Trans. A.M.S. paper ＂The equivariant Plateau problem and interior regularity＂. Moreover, each of them enjoys （coflat） calibrations singular only at the origin.

关键词： Area-minimizing hypercone coflat calibration comass

The YNEV stellar evolution and oscillation code

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Research in Astronomy and Astrophysics 2015年第4期15卷 549-568页

作者： Qian-sheng zhang Yunnan Observatories Chinese Academy of Sciences Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences

We have developed a new stellar evolution and oscillation code YNEV, which calculates the structures and evolutions of stars, taking into account hydrogen and helium burning. A nonlocal turbulent convection theory and an updated over- shoot mixing model are optional in this code. The YNEV code can evolve low- and intermediate-mass stars from the pre-main sequence to a thermally pulsing asymptotic branch giant or white dwarf. The YNEV oscillation code calculates the eigenfrequen- cies and eigenfunctions of the adiabatic oscillations for a given stellar structure. The input physics and numerical scheme adopted in the code are introduced. Examples of solar models, stellar evolutionary tracks of low- and intermediate-mass stars with different convection theories （i.e. mixing-length theory and nonlocal turbulent con- vection theory）, and stellar oscillations are shown.

关键词： stars -- stellar structure -- stellar evolution -- stellar oscillations

On Graded Selfduality

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Acta Mathematica Sinica,English Series 2001年第1期17卷 113-118页

作者： sheng Gui zhang Department of Mathematics Fujian Normal University

In this paper, we discuss the connection between the rigid graded selfduality over some noncommutative graded ring and the selfduality over its initial subring.

关键词： Selfduality Graded selfduality

ADDED MASS OF UNDERWATER PLATES AND BEAM STIFFENED PLATES IN VIBRATION

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Journal of Hydrodynamics 1991年第2期3卷 13-20页

作者： zhang, sheng-ming China Ship Scientific Research Cent Wuri China

In this paper, the added mass of plates and beam stiffened plates vibrating in water are summarized for the purpose of convenience in engineering design. The analytical formulae, calculated data tables, calculated cur... 详细信息

关键词： Mathematical Techniques Boundary Element Method Plates Vibrations Ships Vibrations Tanks Vibrations