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低扬程泵装置原、模型和防止“有害”汽蚀参数换算

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排灌机械工程学报 2015年第3期33卷 185-195页

作者：周君亮江苏省水利厅江苏南京210029

依据中国泵和泵站模型水工试验作设计前期工作时,行业规定在泵水力装置模型制作中要求过流流道几何相似,但表面粗糙度与原型按一定比例相等和不重视容积损失相似,有比尺效应;在模型试验中,流道水流流态可能有部分在光滑紊流区与原型水... 详细信息

依据中国泵和泵站模型水工试验作设计前期工作时,行业规定在泵水力装置模型制作中要求过流流道几何相似,但表面粗糙度与原型按一定比例相等和不重视容积损失相似,有比尺效应;在模型试验中,流道水流流态可能有部分在光滑紊流区与原型水流态不相同和允许降低原型泵转速做模型试验,有Re数效应;两者造成原、模型水力参数换算后误差很大,须用经验公式修正,各国学者已提出了十几个经验公式.提出了人工消除参数中的比尺效应和Re数效应,将模型试验成果按不等效率换算成与原型泵流道几何相似、水流流速相同、水力效率不相同的新模型,新模型成果由水工相似定律等效率换算成新模型原型水力参数,并可防止叶型"有害"汽蚀.采用该方法换算皂河第一抽水站模型试验为原型水力参数,与试运行成果符合.

关键词：泵水力装置参数水力损失容积损失机械损失比尺效应 Re数效应汽蚀比转数

Study on the proposed environmental guidelines for Cd, Hg, Pb and As in soil of China

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Journal of Environmental Sciences 1992年第1期4卷 66-73页

作者： Wu Yanyu, Tian junliang zhou QixingInstitute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110015, ChinaNorthwest Institute of Water and Soil Conservation, Chinese Academy of Sciences, Shaanxi 712100, China

This paper deals with the soil-environmental standard. According to the current situation of researching on the soil-environmental quality guideline at home and abroad, and on the basis of the foundations and principles of enacting the soil-environmental standard, the soil environment quality guideline values of Hg, Cd, Pb and As were suggested.

关键词： soil-environmental standard soil guideline heavy metal functional land use soil background content.

Polymer-supported chiral palladium-based complexes as efficient heterogeneous catalysts for asymmetric reductive Heck reaction

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Green Synthesis and Catalysis

Green Synthesis and Catalysis 2024年第2期5卷 102-107页

作者： Hui Zhang Bing Xu Liejin zhou Zhan-Ming Zhang junliang Zhang College of Marine Ecology and Environment Shanghai Ocean University999 Hucheng Ring RoadShanghai 201306China Department of Chemistry Fudan University2005 Songhu RoadShanghai 200438China Graduate School of Pharmaceutical Sciences Tohoku UniversitySendai 980-8578Japan Fudan Zhangjiang Institute Shanghai 201203China

Heterogeneous asymmetric catalysis is an important strategy for the industrial production of chiral ***,we reported a polymer-bound Xu-Phos-derived palladium catalyst that shows good performance in heterogeneous asymmetric reductive Heck reaction of allyl aryl *** heterogeneous catalyst was easily prepared by efficient immobilization of the sulfonamide phosphine ligand(Xu-Phos)in the cross-linked polystyrene via copolymerization,and exhibits similar catalytic activity and enantioselectivity to that of the homogeneous ***,the heterogeneous catalyst system is proved to be easily recovered and reused several times without losing catalytic activity obviously.

关键词： Heterogeneous catalysis Recoverability Palladium Hydroarylation Asymmetric catalysis

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渤中M油田低渗储层裂缝特征及对开发的影响

特种油气藏 2018年第3期25卷 102-107页

作者：周军良中海石油(中国)有限公司天津分公司天津300459

M油田为海上低渗油藏开发先导试验区,明确裂缝特征及其对开发的影响对提高试验区开发效果具有重要意义。运用岩心、薄片、成像测井、试产等资料,利用地质学、统计学方法得出储层裂缝对产能的影响。结果表明:渤中M油田低渗储层以高角度... 详细信息

M油田为海上低渗油藏开发先导试验区,明确裂缝特征及其对开发的影响对提高试验区开发效果具有重要意义。运用岩心、薄片、成像测井、试产等资料,利用地质学、统计学方法得出储层裂缝对产能的影响。结果表明:渤中M油田低渗储层以高角度、低角度宏观构造裂缝和微观粒内缝为主;裂缝分布受构造、岩性、层厚、异常高压等因素控制;有效裂缝主要发育在背斜核部及断层上盘,是薄油层区域影响开发井产能的关键因素,决定了注采开发的效果。成果与目前生产动态吻合性好,有助于试验区低效井的治理及扩大注水规模,改善开发效果,也可为类似区块勘探开发提供借鉴。

关键词：低渗储层裂缝产能影响因素沙河街组渤中M油田

A Concise Synthesis of 2,4-Disubstituted and 2,3,4-Trisubstituted Pyrroles

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A Concise Synthesis of 2,4-Disubstituted and 2,3,4-Trisubsti...

从知识至上到生命关怀:建国以来课堂教学质量观的演进轨迹

中国化学会·第十六届全国有机合成化学学术研讨会

作者：刘唱 Yue Jin junliang zhou Jian Zhang Weili Zhao 河南大学 Key Laboratory for Special Functional Materials of the Ministry of Education Henan University School of Pharmacy Fudan University

Pyrroles are one of the most prevalent heterocyclic compounds,and are widely present as the basic cores in many natural *** pharmaceutical compounds,and a variety of functional *** many strategies for pyrroles have been developed,access to 2,4-disubstituted/2,3,4-trisubstituted pyrroles remains *** our previous reports,we have prepared 2,4-diaryl and conformationally restricted pyrroles with 2 H-azirines as the key ***,the instability and scarcity of 2 H-azirines,as well as hazardous re agent(s)(iodine azide or sodium azide/Br)required for the preparation limited the *** development of novel synthetic strategy for pyrroles remains an ongoing *** this work,a concise approach that constructs a wide range of 2,4-disubstituted and 2,3,4-trisubstituted pyrroles using simple and easily available materials with in situ generated 2 H-azirine as the key intermediate is *** circumvent instability of ketoxime sulfonates due to Beckman rearrangement,a one-pot strategy using in situ generated ketoxime sulfonates is also *** one-pot method afforded more convenient access to various pyrroles with improved yields and opened up novel possibility to construct pyrroles with great variety of substitution patterns.

关键词： pyrroles synthesis 2,4-disubstituted 2,3,4-trisubstituted ketoxime sulfonates ketones

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现代教育管理 2018年第1期 92-97页

作者：周俊良华中师范大学湖北武汉430079

教学质量观是教学实践发展的晴雨表,是指导教学变革的方向性指南。中华人民共和国成立至今,课堂教学质量观由过去对智育第一、知识至上的尊崇过渡到对学生生命发展独特性、整体性的尊重,并开始关注教学内容、过程与学生生命意义的联系,... 详细信息

教学质量观是教学实践发展的晴雨表,是指导教学变革的方向性指南。中华人民共和国成立至今,课堂教学质量观由过去对智育第一、知识至上的尊崇过渡到对学生生命发展独特性、整体性的尊重,并开始关注教学内容、过程与学生生命意义的联系,呈现出鲜明的阶段性特征。教学质量观的这种演变实质上是工具理性与价值理性间互相博弈的过程,它与对人本性之认识程度相关,并随之变化。此外,教学质量观的变迁与教学实践的发展并非总是亦步亦趋,而是存在观念与实践脱节的现象。

关键词：教学质量观演变轨迹知识至上生命关怀

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沉积物与盐度对罗红霉素生物有效性的影响

生态毒理学报 2017年第3期12卷 460-469页

作者：陈悦周俊良华东师范大学河口海岸学国家重点实验室上海200062

在河口环境,沉积物与盐度对抗生素的生物有效性有重要影响。使用超高效液相色谱-串联质谱(UPLC-MS/MS)分析单一和复合控制系统(水、水-沉积物、水-斑马鱼、水-沉积物-斑马鱼)中的各相态中的罗红霉素,以期量化各相态中罗红霉素的迁移、... 详细信息

在河口环境,沉积物与盐度对抗生素的生物有效性有重要影响。使用超高效液相色谱-串联质谱(UPLC-MS/MS)分析单一和复合控制系统(水、水-沉积物、水-斑马鱼、水-沉积物-斑马鱼)中的各相态中的罗红霉素,以期量化各相态中罗红霉素的迁移、分布。随着暴露时间延长,水体中罗红霉素浓度不断减少,沉积物和斑马鱼体内罗红霉素不断蓄积。沉积物的存在会减少罗红霉素在斑马鱼中的生物有效性。在高盐度环境下,沉积物拥有更大的吸附效率,符合盐析效应,导致罗红霉素的生物有效性及斑马鱼富集能力下降。水-沉积物-斑马鱼系统达平衡时,沉积物为罗红霉素的主要富集场所,可积累42.0%的罗红霉素。同时,斑马鱼可吸收和富集0.16%的罗红霉素。上述研究为研究抗生素环境行为和毒理提供了参考。

关键词：罗红霉素斑马鱼生物有效性沉积物盐度

A 9.5-kb deletion in the 1st intron of OsMADS51 enhances temperature sensitivity in rice

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The Crop Journal 2024年第4期12卷 1031-1040页

作者： Lei Zhao Haifei Hu Junyu Chen Chongrong Wang Yibo Chen Hong Li Daoqiang Huang Zhidong Wang Degui zhou Rong Gong Yangyang Pan junliang Zhao Liangyong Ma Shaochuan zhou Rice Research Institute Guangdong Academy of Agricultural SciencesGuangzhou 510640GuangdongChina State Key Laboratory of Rice Biology and Chinese National Center for Rice Improvement China National Rice Research InstituteHangzhou 310006ZhejiangChina Guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510640GuangdongChina Key Laboratory of Genetics and Breeding of High Quality Rice in Southern China(Co-construction by Ministry and Province) Ministry of Agriculture and Rural AffairsGuangzhou 510640GuangdongChina Guangdong Rice Engineering Laboratory Guangzhou 510640GuangdongChina Guangdong Key Laboratory of New Technology in Rice Breeding Guangzhou 510640GuangdongChina

Temperature is an important environmental factor affecting heading date of *** its importance,genes responsible for temperature-sensitive heading in rice have remained *** previous study identified a quantitative trait locus qHd1 which advances heading date under high temperatures.A 9.5-kb insertion was found in the first intron of OsMADS51 in indica variety Zhenshan 97(ZS97).However,the function of this natural variant in controlling temperature sensitivity has not been *** this study,we used CRISPR/Cas9 to knock out the 9.5-kb insertion in *** conducted under cotrolled conditions in phytotrons confirmed that deletion increased temperature sensitivity and advanced heading by downregulating the expression level of ***-hybrid assays in yeast,ChIP-quantitative polymerase chain reaction,electrophoretic mobility shift,and luciferase-based transient transactivation assays collectively confirmed that OsMADS51 affects heading date by regulation of heading date gene *** further determined that the long non-coding RNA HEATINR is generated from the first intron of OsMADS51,offering an explanation for how the 9.5-kb insertion affects temperature *** also found that OsMADS51 was strongly selected in early/late-season rice varieties in South China,possibly accounting for their strong temperature *** insights not only advance our understanding of the molecular mechanisms underlying the temperature-responsive regulation of heading date in rice but also provide a valuable genetic target for molecular breeding.

关键词： OsMADS51 Insertion Long non-coding RNA Oryza sativa

Construction of Multiple Carbon-Carbon Bonds via in situ-Derived Diazo Intermediate from α-Halo-N-tosylhydrazones

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Construction of Multiple Carbon-Carbon Bonds via in situ-Der...