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青海省春小麦田杂草群落组成及其多样性分析

干旱地区农业研究 2024年第2期42卷 254-263页

作者：付贞桢魏有海郭良芝翁华程亮朱海霞李玮陈红雨青海大学农林科学院青海西宁810016 青海省农林科学院青海西宁810016

为明确青海省春小麦田杂草发生种类及其群落特征,采用倒置“W”九点取样法对青海省东部农业区和柴达木盆地农业区春小麦田杂草种类、生活型、科属组成、群落结构及杂草多样性进行调查。统计分析发现:小麦田有85种杂草,隶属24科64属。其... 详细信息

为明确青海省春小麦田杂草发生种类及其群落特征,采用倒置“W”九点取样法对青海省东部农业区和柴达木盆地农业区春小麦田杂草种类、生活型、科属组成、群落结构及杂草多样性进行调查。统计分析发现:小麦田有85种杂草,隶属24科64属。其中,菊科和禾本科是数量最多的科别,杂草分别为16种和14种。从杂草的综合优势度来看,藜(chenopodium album L.)、野燕麦(Avena fatua L.)、萹蓄(Polygonum aviculare L.)、苦苣菜(Sonchus oleraceus L.)、苣荬菜(Herba Sonchi Brachyoti)5种杂草为优势杂草,芦苇(Phragmites australis(Cav.)Trin.)、赖草(Leymus secalinus(Georgi)Tzvel.)、狗尾草(Setaria viridis(Linn.)Beauv.)、藏蓟(Cirsium eriophoroides)、荞麦蔓(Fagopyrum esculentum Moench.)、节裂角茴香(Hypecoum leptocarpum *** Thoms.)、猪殃殃(Galium spurium L.)、大刺儿菜(Cirsium arvense ***(willd.)Ledeb)、密花香薷(Elsholtzia densa Benth.)、野油菜(Brassica juncea(L.)*** Coss.)10种杂草为区域性优势杂草。此外有常见杂草22种,一般性杂草48种。东部农业区田间杂草物种丰富度较柴达木地区高,湟中区、大通县、互助县麦田杂草的物种丰富度依次为46、45、42;柴达木盆地的都兰县、德令哈市、乌兰县、格尔木市麦田杂草的物种丰富度依次为30、26、23、13,调查区以格尔木市的物种丰富度最小。比较杂草的生活型发现,同一地区越年生杂草、多年生杂草的发生数量和一年生杂草的数量基本接近50%;从杂草群落的相似性来看,东部农业区的湟中区、互助县、大通县杂草群落组成极为相似,而柴达木盆地绿洲农业区的都兰县、德令哈市、格尔木市、乌兰县杂草群落相似性程度高,杂草群落结构的相似性结果与区域小麦生产实际相吻合。群落结构组成和区域耕作制度、气候条件、土壤理化性质、田间管理水平等具有较大的相关性,建议加强杂草优势种和区域性优势杂草的防控和监测,因地制宜制定杂草绿色防控措施。

关键词：春小麦田杂草群落组成物种多样性青海省

GB/T 24733—2023《等温淬火球墨铸铁件》国家标准修订解读

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铸造 2024年第9期73卷 1336-1341页

作者：崔宇赵竞翔李增利李克锐陈昭杜瑞昌王拓郑州机械研究所有限公司河南郑州450001

介绍了GB/T 24733—2023《等温淬火球墨铸铁件》修订过程,论述了标准的主要修订内容,解读了与原标准和ISO 17804:2020《铸造奥铁体球墨铸铁分类》的主要技术差异和修订缘由,指出了新标准的特点和应用范围。

关键词：等温淬火球墨铸铁奥铁体球墨铸铁标准解读

Effects of water discharge on river-dominated delta growth

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Petroleum Science 2021年第6期18卷 1630-1649页

作者： Yan-Bao Zhang Yi-ke Liu Jia Yi Xue-Jian Liu Institute of Geophysics China Earthquake AdministrationBeijing100081China key Laboratory of Petroleum Resources Research Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China China Earthquake Disaster Prevention Center China Earthquake AdministrationBeijing100029China The Pennsylvania State University Department of GeosciencesUniversity ParkPA16802USA

River-dominated deltas are commonly developed at modern bays and lakes and ancient petroliferous *** discharge is an important variable at pay zone scales in river-dominated delta reservoirs,which affects deltaic sand distributions and ***,it's unclear how it influences riverdominated delta *** paper integrates Delft3 D simulations and modern analogs to analyze the effects of water discharge,considering growth time,sediment supply,and coupled effects of sediment *** water discharges lead to the formation of lobate deltas,and the water discharge of 1,000 m~3/s is a referenced threshold ***-grained,highly-cohesive sediments increase the threshold values of water discharge at which the deltas become lobate from digitate,and vice *** the same simulation time,high water discharges favor more rugose shorelines,more distributary channels(especially secondary distributaries),and longer and wider deltas with more land ***,for the same sediment supply,high water discharges have few effects on shoreline roughness and the number of distributary channels.

关键词： River-dominated delta Water discharge Morphology Distributary channel Hydrocarbon exploration

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轻型汽油车NH_(3)排放研究

汽车工程 2024年第3期46卷 483-488页

作者：方娜陈涛管永超方勇万建刘成田颖秦建宾王小涛康文霞东风汽车集团有限公司技术中心武汉430058

研究了某1.5T SUV车不同排放测试循环(WLTC与CLTC)和催化剂不同状态(新鲜和老化)对NH_(3)排放的影响。通过试验研究表明:发动机原始NH_(3)排放量很低,而经过第一块三元催化剂后,NH_(3)排放量大幅增加。催化剂老化后OSC降低,内部空燃比... 详细信息

研究了某1.5T SUV车不同排放测试循环(WLTC与CLTC)和催化剂不同状态(新鲜和老化)对NH_(3)排放的影响。通过试验研究表明:发动机原始NH_(3)排放量很低,而经过第一块三元催化剂后,NH_(3)排放量大幅增加。催化剂老化后OSC降低,内部空燃比波动幅度大,经过老化催化剂的NH_(3)排放相对新鲜催化剂的NH_(3)排放有所增加。催化剂状态、排放测试循环和发动机空燃比等对NH_(3)排放有明显影响,这些对于催化剂设计和标定优化均有指导意义。

关键词： NH_(3)排放三元催化剂排放循环空燃比

Dynamic performance of a long-stroke fast tool servo system

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Nanotechnology and Precision Engineering 2022年第2期5卷 38-53页

作者： Zheng Gong Dehong Huo Zengyuan Niu Wanqun chen Kai cheng School of Engineering Newcastle UniversityNewcastle upon Tyne NE17RUUnited Kingdom UPTech Jiangsu Industrial Technology Research InstituteKunshan 215300China School of Electromechanical Engineering Soochow UniversitySoochow 215031China School of Engineering and Design Brunel University LondonLondon UB83PHUnited Kingdom

A fast tool servo(FTS)system can be used to efficiently manufacture optical freeform *** paper investigates the dynamic performance of an FTS system driven by a voice coil motor and guided by air bearings.A simulation model and testing platform are developed to evaluate the load capacity and stiffness of the air *** mechanical dynamic performance of the designed FTS,including modal and harmonic analyses,is assessed using finite element analysis.A nonlinear relation between air-bearing stiffness and mechanical bandwidth is *** working dynamic performance is tested through system runout,tracking performance,and closed-loop *** relations between air-bearing stiffness and the mechanical and working bandwidths are established and *** experiments verify the feasibility of the FTS system with 31.05 N/μm stiffness air-bearings.

关键词： FTS Dynamic performance Air bearing Stiffness

Exploring the effect of Arctic perennial sea ice on modulation of local air temperature

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Advances in Climate Change Research 2022年第4期13卷 473-488页

作者： Yu-Fang YE Mohammed SHOKR Zhuo-Qi chen Xiao cheng School of Geospatial Engineering and Science Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Science and Technology Branch Environment and Climate Change CanadaToronto M3H5T4Canada

Sea ice cover plays an important role in modulating local temperature through heat and moisture *** infuence of thin ice lead and polynya has been wellinvestigated,however,the effect of perennial ice(also called muliyear ice,MYI)has *** study is motivated by it and investigated a hypothesis that changes in MYI concentration in winter triggers changes in short-term local 2-m air *** hypothesis was tested using time series analysis of the two parameters and correlation between *** from the winters of 2004-2009 were used for the examination at three spatial *** hypothesis is found to be potentially accepted when MYI exists in a consolidated ice regime with negligible thin ice or open water in the surroundings,and the air temperature is low *** for the acceptance of the hypothesis were quantitatively *** qualifications entail that the ice cell must experience daily change of MYI concentration meanwhile satisfy the criteria of total ice concentration(TIC),young ice concentration(YIC)and air temperature(Tar)in the surrounding area,which are TIC>88.3%,YIC<9.5%and T_(air)<-19.0℃.Inverse relationships between changes in MYI concentration and the corresponding changes in air temperature were developed retroactively using data that satisfied the acceptance *** relationships varied with years,depending on ice conditions such as ice type distributions and snow *** study offers a first attempt to assess the effect of MYI on the same-day local surface air temperature using satelite observations,and provides evidence of this effect under quantitatively quanlifying conditions.

关键词： Arctic sea ice Multiyear ice Arctic response to climate change Microwave remote sensing

Elite capture,the“follow-up checks”policy,and the targeted poverty alleviation program:Evidence from rural western China

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Journal of Integrative Agriculture 2021年第4期20卷 880-890页

作者： cheng Xiao-yu WANG Jian-ying kevin Z.chen Institute of Agricultural Economics and Development Chinese Academy of Agricultural SciencesBeijing 100081P.R.China School of Economics Zhejiang University of Finance&EconomicsHangzhou 310018P.R.China China Academy for Rural Development Zhejiang UniversityHangzhou 310058P.R.China International Food Policy Research Institute WashingtonD.C.20005USA

Decentralized methods for targeting poverty are widely adopted in developing countries to improve the performance of various poverty alleviation programs.A common challenge for implementing successful decentralized targeting is the existence of elite *** has recently implemented a nationwide decentralized poverty targeting program,the targeted poverty alleviation(TPA)policy,to achieve the national goal of eliminating absolute poverty by the end of *** the largest decentralized poverty targeting program in the world,TPA's successful implementation was believed to be threatened by elite capture in some earlier *** 2015,a targeting correction mechanism,called"follow-up checks"policy,has been *** the"follow-up checks"policy,the elites and other ineligible households who receive benefits under TPA were removed from the *** paper investigates the elite capture phenomenon in TPA using village census data from a poverty-stricken county in 2017-two years after implementing the"follow-up checks"*** find no evidence of elite capture in *** elites are unlikely to become beneficiaries or receive more benefits than *** results contradict earlier findings that reported elite capture in *** argue that the reason is the accountability emphasized by the central government in the"follow-up checks"*** findings imply that having proper accountability is critical for improving targeting performance by global antipoverty initiatives.

关键词： elite capture decentralized poverty targeting targeted poverty alleviation the"follow-up checks"policy accountability

Reduced water dissociation barrier on constructing Pt-Co/CoO_(x)interface for alkaline hydrogen evolution

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Nano Research 2022年第6期15卷 4958-4964页

作者： Yandong Wang Wei Wu Runzhe chen Caoxin Lin Shichun Mu Niancai cheng College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China State key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Water dissociation process is generally regarded as the rate-limiting step for alkaline hydrogen evolution reaction(HER),and severely inhibits the catalytic efficiency of Pt based *** overcome this problem,the in-situ constructed interfaces of PtCo alloy and amorphous cobalt oxide(CoO_(x))on the carbon powder are *** amorphous CoO_(x)at Pt-Co/CoO_(x)interfaces not only provide active sites for water dissociation to facilitate Volmer step,but also produce the strong electronic transfer with ***,the obtained interfacial catalysts exhibit outstanding alkaline HER performance with a Tafel slope of 29.3 mV·dec^(−1)and an ultralow overpotential of only 28 mV at 10 mA·cm^(−2).Density functional theory(DFT)reveals that the electronic accumulation on the interfacial Co atom in Pt-Co/CoO_(x)constructing the novel active site for water *** to the Pt-Co,all of the energy barriers for water adsorption,water dissociation and hydrogen adsorption/desorption are reduced in Pt-Co/CoO_(x)interfaces,suggesting a boosted HER kinetics for alkaline HER.

关键词： interfacial construction amorphous cobalt oxide water dissociation dual active site electronic regulation

芪黄健脾滋肾颗粒对系统性红斑狼疮患者疗效及STAT3/mTOR信号通路的影响

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中国实验方剂学杂志 2024年第8期30卷 118-125页

作者：汤忠富黄传兵程丽丽陈君洁尚双双李明刘思娣安徽中医药大学第一附属医院合肥230031

目的:探讨芪黄健脾滋肾颗粒治疗系统性红斑狼疮(SLE)的临床疗效及对信号转导及转录激活因子3/哺乳动物雷帕霉素靶蛋白(STAT3/m TOR)信号通路的影响,分析其可能作用机制。方法:选取安徽中医药大学第一附属医院2022年5月至2023年5月符合... 详细信息

目的:探讨芪黄健脾滋肾颗粒治疗系统性红斑狼疮(SLE)的临床疗效及对信号转导及转录激活因子3/哺乳动物雷帕霉素靶蛋白(STAT3/m TOR)信号通路的影响,分析其可能作用机制。方法:选取安徽中医药大学第一附属医院2022年5月至2023年5月符合标准的SLE女性患者60例,随机分成对照组和观察组(每组各30例),对照组予以醋酸泼尼松+硫酸羟氯喹口服;观察组在对照组基础上予以芪黄健脾滋肾颗粒口服。连续治疗8周后,评估两组患者治疗前后SLE疾病活动度(SLEDAI)、中医证候积分,比较治疗前后血红细胞沉降率(ESR)、超敏C反应蛋白(hs-CRP)、免疫指标[免疫球蛋白G(Ig G)、C3、C4、CD4^(+)、CD8^(+)]、白细胞介素(IL)-17、IL-23、γ干扰素(IFN-γ)、24 h尿蛋白定量(24 h PRO)、血肌酐(SCr)、STAT3/m TOR通路相关因子[STAT3、磷酸化(p)-STAT3、m TOR蛋白和STAT3、m TOR m RNA]表达变化及不良反应情况。结果:经8周治疗后,观察组临床总有效率为93.33%(28/30),明显高于对照组临床总有效率的70.00%(21/30)(χ^(2)=4.007,P<0.05)。与本组治疗前比较,两组患者SLEDAI、中医证候积分、ESR、hs-CRP、Ig G、CD8^(+)、IL-17、IL-23、IFN-γ、24 h PRO、SCr和STAT3/m TOR通路相关因子表达均显著降低(P<0.01),C3、C4、CD4^(+)显著升高(P<0.01)。与对照组治疗后比较,观察组患者SLEDAI、中医证候积分、ESR、hs-CRP、Ig G、CD8^(+)、IL-17、IL-23、IFN-γ、24 h PRO、SCr和STAT3/m TOR通路相关因子表达均明显降低(P<0.05,P<0.01),C3、C4、CD4^(+)明显升高(P<0.05,P<0.01)。两组治疗前后均未出现严重不良反应。结论:芪黄健脾滋肾颗粒能有效改善SLE机体炎症反应,降低疾病活动度,改善肾损伤,其机制可能与抑制STAT3/m TOR信号通路调节免疫功能有关。

关键词：系统性红斑狼疮芪黄健脾滋肾颗粒信号转导及转录激活因子3/哺乳动物雷帕霉素靶蛋白(STAT3/mTOR)信号通路免疫炎症六味地黄汤四君子汤