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Spatial distribution of soil salinization under the influence of human activities in arid areas, China

Journal of Arid Land 2024年第10期16卷 1344-1364页

作者： LIU Yufang YANG Qingwen PEI Xiangjun LI Jingji wang shuangcheng HUANG Zhenfu HAN Wei ZHENG Tianliang College of Ecology and Environment Chengdu University of Technology Tianfu Yongxing Laboratory Hydrogeological and Engineering Geological Team of Xinjiang Bureau of Geo-Exploration & Mineral Development

The Hotan Prefecture of Xinjiang Uygur Autonomous Region, China belongs to arid desert climate, with significant soil salinization issues. The study selected six rivers in Hotan Prefecture（Pishan, Qaraqash, Yurungqash, Celle, Kriya, and Niya rivers） to explore the spatial distribution of soil salinization in this area and its underlying mechanisms. Sampling was conducted along each river's watershed, from the Gobi in the upper reaches, through the anthropogenic impact area in the middle reaches, to the desert area in the lower reaches. Soil physical-chemical indicators, including total soluble salts, pH, K+, Na+, Ca2+, Mg2+, SO42–, Cl–, CO32–, HCO3–, organic matter, available nitrogen, available phosphorus, and available potassium, were tested, along with the total dissolved solids of surface water and groundwater. The results revealed that the soil water and nutrient contents in anthropogenic impact area were higher than those in Gobi and desert areas, while the p H and total soluble salts were lower than those in Gobi and desert areas. The ions in the soil of the study area were primarily Cl–, SO42–, K+, and Na+, and the ion concentration of soil salt were positively correlated with surface water and groundwater. Overall, the study area exhibited low soil water content, low clay content, infertile soil, and high soil salinization, dominated by weak to moderate chloride-sulfate types. Compared with Gobi and desert areas, the soil in anthropogenic impact area had higher soil water content, lower p H, lower soluble salts, and higher nutrients, indicating that human farming activities help mitigate salinization. These findings have practical implications for guiding the scientific prevention and control of soil salinization in the arid areas and for promoting sustainable agricultural development.

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青海西宁方言的话题结构和宾动结构

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方言 2024年第3期46卷 348-359页

作者：王双成上海师范大学人文学院上海

青海西宁方言的宾动结构(OV)一直以来受到学者们的高度关注,主要原因是在同周边SOV语言的接触过程中,西宁方言的语序出现明显的SOV化,格标记的产生更使得其离VO语序越来越远。由于话题结构和宾动结构在语序上的最大共性是名词性成分都... 详细信息

青海西宁方言的宾动结构(OV)一直以来受到学者们的高度关注,主要原因是在同周边SOV语言的接触过程中,西宁方言的语序出现明显的SOV化,格标记的产生更使得其离VO语序越来越远。由于话题结构和宾动结构在语序上的最大共性是名词性成分都前置于动词,无形中出现“雷同”。西宁方言虽然发展出了真正意义上的OV语序,但这并不等于说西宁方言没有话题结构,西宁方言的宾动结构和话题结构在形式上也存在明显的区分,宾语带有宾格标记“下”[·xa],话题一般可以带话题标记“吵”[·sa]或“嘛”[·ma](非强制)。西宁方言的否定句、疑问句也是最重要的话题化条件,这同吴语等话题优先的方言具有共性。

关键词：青海西宁方言中原官话话题结构宾动结构语言接触

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不同热处理热轧搪瓷钢含钛析出相的定性定量分析

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冶金分析 2024年第3期44卷 1-7页

作者：缪乐德张毅王双成宝山钢铁股份有限公司中央研究院

热轧搪瓷用钢要求具备良好的抗鳞爆性能，要提高贮氢性能即增加氢陷阱，最有效的方法是增加钢中析出相的含量。为了对不同热处理的热轧搪瓷钢的析出相进行定量分析，本文采用电解提取方法将析出相从基体中分离，通过扫描电镜(SEM)和X射... 详细信息

热轧搪瓷用钢要求具备良好的抗鳞爆性能，要提高贮氢性能即增加氢陷阱，最有效的方法是增加钢中析出相的含量。为了对不同热处理的热轧搪瓷钢的析出相进行定量分析，本文采用电解提取方法将析出相从基体中分离，通过扫描电镜(SEM)和X射线衍射(XRD)定性研究了提取后析出相的形貌以及结构的变化过程；并利用Rietveld全谱拟合法计算不同析出相的组成及含量。同时采用透射电镜(TEM)和三维原子探针(3DAP)对纳米级析出相进行了表征。最后，探讨了热轧搪瓷钢中析出相与贮氢性能的关系。结果表明，通过XRD检测，热轧搪瓷钢中的析出相主要为Ti2CS、TiC0.95和TiC0.3N0.7;透射电镜显示150 nm以上粗大析出物含有硫，为碳硫化钛，100 nm左右的碳化钛，以及10 nm级的大量析出，且分布不均匀，3DAP确认其为碳化钛。850℃热处理的试样析出相的含量(质量分数，下同)最高，达到了0.39%,颗粒比表面积最大，氢穿透实验显示其平均穿透时间最长，有更高的贮氢性能。

关键词：热轧搪瓷钢析出相热处理电解定性定量分析

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Restricted Bayesian classification networks

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Science China(Information Sciences) 2013年第7期56卷 210-224页

作者： wang shuangcheng XU GuangLin DU RuiJie School of Mathematics and Information Shanghai Lixin University of Commerce Open Economic and Trade Research Center Shanghai Lixin University of Commerce

Bayesian networks are graphical models that describe dependency relationships between variables, and are powerful tools for studying probability classifiers. At present, the causal Bayesian network learning method is used in constructing Bayesian network classifiers while the contribution of attribute to class is over-looked. In this paper, a Bayesian network specifically for classification-restricted Bayesian classification networks is proposed. Combining dependency analysis between variables, classification accuracy evaluation criteria and a search algorithm, a learning method for restricted Bayesian classification networks is presented. Experiments and analysis are done using data sets from UCI machine learning repository. The results show that the restricted Bayesian classification network is more accurate than other well-known classifiers.

关键词： restricted Bayesian classification network Bayesian network classifier classification accuracy dependency analysis

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KNO_(3)对NaCl胁迫下苹果砧木T337幼苗生理特性的影响

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甘肃农业大学学报 2024年第1期59卷 123-134页

作者：程娇高彦龙张瑞张德张仲兴王双成王延秀甘肃农业大学园艺学院甘肃兰州730070

【目的】研究100 mmol/L NaCl胁迫下不同浓度KNO_(3)对T337幼苗生理特性的影响。【方法】以盆栽2年生苹果砧木T337为试验材料,本试验设置6个处理,即CK1(浇灌清水)、盐胁迫(CK2)以及盐胁迫+喷施4种浓度KNO_(3)[0.1(T_(1))、0.2(T_(2))、0... 详细信息

【目的】研究100 mmol/L NaCl胁迫下不同浓度KNO_(3)对T337幼苗生理特性的影响。【方法】以盆栽2年生苹果砧木T337为试验材料,本试验设置6个处理,即CK1(浇灌清水)、盐胁迫(CK2)以及盐胁迫+喷施4种浓度KNO_(3)[0.1(T_(1))、0.2(T_(2))、0.3(T_(3))、0.4 mg/L(T_(4))],测定各处理叶片的叶绿素含量、光合荧光参数、抗氧化酶活性及渗透调节物质的含量,并利用主成分分析对其进行综合评价。【结果】随盐胁迫(CK2)时间的延长,T337叶片光合色素(Chl a、Chlb、Chla/b、Chla+b),气孔导度(Gs)、蒸腾速率(Tr)、净光合速率(Pn)、PSⅡ最大光化学效率(Fv/Fm)、光化学淬灭系数(qP)含量均呈逐渐下降的趋势,非光化学淬灭系数(qN)、初始荧光(Fo)、胞间二氧化碳浓度(Ci)、相对电导率(REC)、丙二醛(MDA)含量、脯氨酸(Pro)均呈上升趋势,超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)呈先升后降的趋势。与CK1相比,盐胁迫+外源KNO_(3)(T_(1)-T_(4))处理后T337幼苗叶片各指标均呈现不同幅度变化,且存在明显的浓度效应,并以T_(3)(0.3 mg/L KNO_(3))处理叶片叶绿素含量、Gs、Tr、Pn、Fv/Fm、qP降幅最小,Ci、REC、MDA、qN、Fo升幅最小,Pro及SOD、POD、CAT升幅最大。综合评价表明,各处理对T337幼苗特性的效应依次为:CK1>T_(3)>T_(1)>T_(2)>T_(4)>CK2。【结论】综上,施用适宜浓度外源KNO_(3)可有效改善盐胁迫下T337幼苗光合能力,显著提高抗氧化酶活性和渗透调节物质含量,降低细胞膜透性,从而达到缓解盐胁迫的作用,且以0.3 mg/L KNO_(3)处理缓解盐胁迫对T337造成的伤害效果最好。

关键词：苹果 T337 盐胁迫 KNO_(3) 生理特性

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Asymptotic solution of thermocapillary convection in two immiscible liquid layers in a shallow annular cavity

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Science China(Technological Sciences) 2010年第6期53卷 1655-1665页

作者： LI YouRong,wang shuangcheng,WU ShuangYing & SHI WanYuan College of Power Engineering,Chongqing University,Chongqing 400044,China College of Power Engineering Chongqing University

The steady laminar two-dimensional thermocapillary convection of two superposed horizontal liquid layers in a shallow annular cavity was investigated using asymptotical *** liquids were supposed to be immiscible with a nondeformable *** cavity was heated from the outer cylindrical wall and cooled at the inner *** and top surfaces were rigid and *** solutions were obtained in the core region in the limit as the aspect ratio,which was defined as the ratio of the lower layer thickness to the gap width,and trended to *** numerical experiments were also carried out to compare with the asymptotic solution of the steady two-dimensional thermocapillary *** is found that the expressions of velocity and temperature fields in the core region are valid in the limit of the small aspect ratio.

关键词： asymptotic solution thermocapillary flow two-layer system shallow annular cavity

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Microstructure and properties of Ti-bearing hot-rolled high-strength steel plates for two-sided enameling

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Baosteel Technical Research 2018年第4期12卷 21-27页

作者： wang shuangcheng SUN Quanshe XU Chun Research Institute Baoshan Iron & Steel Co.Ltd. School of Material Science and Engineering Shanghai Institute of Technology

The composition and production technology of the type of hot-rolled steel plate used in two-sided enameling were briefly described. The microstructure and mechanical properties before and after enameling were contrastively investigated,and the precipitates in the samples were analyzed using transmission electron microscope and energy dispersive spectrometer. The results show the ferrite grain size of the steel plate after high-temperature enamel firing to be fine,with a large number of TiC and Ti;C;S;precipitates dispersed throughout the ferrite matrix. After two rounds of enamel firing at a temperature range of 800-890 ℃,its yield strength can still reach342 MPa. The results of a hydrogen permeation test show that the hydrogen storage properties of the steel plate are much better than those of ordinary structural carbon steel. A better bubble structure in the enamel layer can be obtained by this steel plate,with no fish-scale defects on the enameled steel-plate surface.

关键词： hot rolled two-sided enameling precipitates steel plates for enameling

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Effect of gastrointestinal heat retention syndrome on gut microbiota in children with upper respiratory tract infection and lung-heat syndrome

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Journal of Traditional Chinese Medical Sciences 2022年第1期9卷 13-21页

作者： shuangcheng wang Xueyan Ma Liqun Wu He Yu Yanran Shan Yuanshuo Tian Tiegang Liu Xiaohong Gu School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing102488China Department of Pediatrics Dongfang Hospital of Beijing University of Chinese MedicineBeijing100078China

Objective:Gastrointestinal heat retention syndrome(GHRS)is associated with lung-heat syndrome and is related to recurrent respiratory *** respiratory tract infection(URTI)lung heat syndrome is common in *** study will explore the effect of GHRS on the structure and function of gut microbiota in children with URTI lung-heat ***:Participants were divided into both groups using the self-developed URTI scale and the“GHRS Diagnostic Scale$Pediatric Part”:GHRS-positive children(LS group)and GHRS-negative children(L group).General information,clinical symptoms,and stool were *** used 16S rRNA amplicon sequencing technology to determine the gene sequence of the V3eV4 region in feces and measure the gut microbiota of the both groups at the genus ***:A total of 23 children were included in the both *** were 12 cases in the LS group and 11 cases in the L *** was no statistical difference between the both groups in age,gender,height,weight,and body mass *** effective sequences shared by the both groups accounted for 85.66%of the *** the gut microbiota,there was no difference in the a diversity and the b diversity between the both *** with the L group,the LS group had a significant increase in the relative abundance of the Ruminococcus gnavus group,Prevotella-9,Staphylococcus,and Actinomyces(P<.05).The functions of the both groups of microbiota primarily concentrate on metabolism,genetic information processing,and environmental information *** relative abundance of signaling molecules and interactions in the LS group were higher than that in the L group(P<.05).The redundancy analysis(RDA)showed that the URTI score had the greatest impact on the distribution of ***:GHRS may affect the development of URTI lung-heat syndrome by changing the relative abundances of gut microbiota.

关键词： Gastrointestinal heat retention syndrome Upper respiratory tract infection Gut microbiota Lung-heat syndrome Lung-stomach heat retention syndrome 16S rRNA gene sequencing Redundancy analysis Diversity

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Anti-inflammatory mechanism of the non-volatile ingredients performance liquid chromatography-heated electron spray ionization-high resolution mass spectroscope and cell metabolomics

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Journal of Traditional Chinese Medicine 2024年第2期44卷 260-267页

作者： JING Wenguang LIN Xiaoyu LI Chu ZHAO Xiaoliang CHENG Xianlong wang Penglong WEI Feng MA shuangcheng Institute of Control of Chinese Traditional Medicine and Ethnic Medicine National Institutes for Food and Drug ControlBeijing 102629China School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing 102488China Beijing Key Laboratory of Traditional Chinese Medicine Basic Research on Prevention and Treatment of Major Diseases Experimental Research CenterChina Academy of Chinese Medical SciencesBeijing 100700China

OBJECTIVE:To explore the anti-inflammatory components and mechanism of the non-volatile ingredients of ***:High performance liquid chromatographyheated electron spray ionization-high resolution mass spectroscope(HPLC-HESI-HRMS)was used to analyze the chemical constituents of the non-volatile ingredients of *** anti-inflammatory activity of ingredients was evaluated using lipopolysaccharide(LPS)induced RAW264.7 cell inflammation model,and the antiinflammatory mechanism was investigated using multivariate statistical analysis of cell ***:The non-volatile ingredients of patchouli were characterized by HPLC-HESI-HRMS,and 36 flavonoids and 18 other components were *** ingredients of patchouli not only had a good protective effect on the LPS-induced inflammation model of RAW264.7 cells,but also regulated the expression levels of arginine,L-leucine,cholesterol,fructose and sorbitol by down-regulating arginine metabolism,aminoacyl-tRNA biosynthesis,polyol/sorbitol pathway,so as to reduce inflammation and reduce cell ***:The non-volatile ingredients of patchouli had good anti-inflammatory effect and exerted its curative effect by regulating endogenous metabolic pathway to reduce inflammatory response.

关键词： Pogostemon non-volatile ingredients anti-inflammatory cell metabolomics

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Causes of the formation of pit defects on the surface of the enamel layer

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Baosteel Technical Research 2020年第3期14卷 39-43页

作者： WEI Jiao SUN Quanshe wang shuangcheng Research Institute Baoshan Iron&Steel Co.Ltd.Shanghai 201999China

During the production of the inner walls of ovens,pit defects were formed on the surface of the enamel layer that was enameled on the cold-rolled steel via electrostatic powder spraying and *** paper elaborates on the microstructure and element distribution of the enamel-steel interface and the enamel *** microscopy,scanning electron microscopy,and energy-dispersive spectroscopy were adopted to investigate the microstructure of a longitudinal section of the defect,and the pit-forming causes were *** results show that rusty spots lead to pit *** high-temperature firing,there is an inadequate fusion and reaction between iron oxides of the rusty spots and the enamel *** rusty spots are closely related to pretreatment process;thus,to avoid their occurrence,electrostatic powder spraying and sintering should be performed timely after forming,degreasing,and thorough drying of the metal sheets.

关键词： cold-rolled steel for enameling pit defects rusty spots pretreatment process before enameling

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