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基于“Suzuki-Miyaura反应”的有机综合实验

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实验室科学 2024年第5期27卷 12-17,22页

作者：任小雨赵燕王天利四川大学化学学院四川成都610065

钯催化的Suzuki-Miyaura偶联反应作为最直接有效的构建碳碳键的方法,在制备联芳基结构的天然产物、药物中间体以及功能材料中,具有重要意义。将科研前沿热点的相关内容引入本科生的有机实验教学,通过此实验,学生可学习查阅文献,了解过... 详细信息

钯催化的Suzuki-Miyaura偶联反应作为最直接有效的构建碳碳键的方法,在制备联芳基结构的天然产物、药物中间体以及功能材料中,具有重要意义。将科研前沿热点的相关内容引入本科生的有机实验教学,通过此实验,学生可学习查阅文献,了解过渡金属催化的前沿研究进展,掌握TLC监测反应的方法、萃取洗涤及柱层析纯化的方法,学习核磁共振、高效液相色谱鉴定化合物结构的方法,使学生体验有机化学科研实验的全过程,培养学生动手能力和创新能力,激发学生科研兴趣,有效培养学生的创新思维和独立分析问题、解决问题等综合能力。

关键词：过渡金属催化钯催化 Suzuki-Miyaura偶联反应有机综合实验

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高校化学科研实验室的安全问题与管理建议

实验室科学 2024年第4期27卷 210-213页

作者：任小雨赵燕张琴芳四川大学化学学院四川成都610065

近年来全国高校化学实验室安全事故频发,化学实验室安全问题受到国家和社会的高度关注。由于化学科研实验室的特殊性,相比其他化学基础实验室,其安全隐患更多,安全管理难度更大。高校化学科研实验室是科学研究和人才培养的重要基地,为... 详细信息

近年来全国高校化学实验室安全事故频发,化学实验室安全问题受到国家和社会的高度关注。由于化学科研实验室的特殊性,相比其他化学基础实验室,其安全隐患更多,安全管理难度更大。高校化学科研实验室是科学研究和人才培养的重要基地,为确保人才培养和科学研究的顺利进行,化学科研实验室的安全管理工作应予以高度重视。为此,在分析化学科研实验室存在的安全隐患基础上,提出相关的安全管理建议,希望对科研实验室的建设和安全管理提供参考。

关键词：化学科研实验室实验室安全管理实验室建设实验室安全准则

Observations of Dynamic Turbulence in the Lower Stratosphere over Inner Mongolia Using a High-resolution Balloon Sensor Constant Temperature Anemometer

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Advances in Atmospheric Sciences 2022年第3期39卷 519-528页

作者： xiaoyu ren Yi LIU Zhaonan CAI Yuli ZHANG Carbon Neutrality Research Center Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing100029China University of Chinese Academy of Sciences Beijing 100049China

We present characterizations of the dynamic turbulence in the lower stratosphere measured by a new balloon-based system designed for detecting finer scale dynamic turbulence. The balloon-based system included a constant temperature anemometer(CTA) operating at a sampling rate of 2 k Hz at an ascent speed of 5 m s^(-1)(corresponding to a vertical resolution of 2.5 mm), an industrial personal computer, batteries, sensors for ambient temperature and humidity, an A/D converter, and others. The system was successfully launched to 24 km altitude over Bayannur City, Inner Mongolia Province. Results show the spatial intermittence of the turbulence layers, with clear boundaries between turbulent and nonturbulent regions. This is the first time that the dynamic turbulence spectrum down to the viscous sub-range has been obtained throughout the lower stratosphere over China. With that, the energy dissipation rates of dynamic turbulence could be calculated with high precision. The profile of the dissipation rates varied from 7.37 × 10^(-7) to 4.23 W kg^(-1) and increased with altitude in the stratosphere.

关键词： dynamic turbulence stratosphere balloon payload high spatial resolution dissipation rates Inner Mongolia

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特色新品种“香粉3号”蕉果实品质评价

中国南方果树 2024年第5期53卷 80-85页

作者：汪乔英胡玉林任小玉肖伟军胡会刚中国热带农业科学院南亚热带作物研究所/海南省热带园艺产品采后生理与保鲜重点实验室/农业农村部热带果树生物学重点实验室广东湛江524091 华中农业大学园艺林学学院武汉430070

“香粉3号”“香粉1号”蕉同属龙牙蕉(AAB),果香浓郁,果肉细腻,糖度高,口感好。为了明确“香粉3号”蕉的果实品质优势,以“香粉1号”蕉为对照,在断蕾后15、25、45、85(青熟)、88 d(完熟)等5个时期测定比较两个品种可溶性糖、可滴定酸、... 详细信息

“香粉3号”“香粉1号”蕉同属龙牙蕉(AAB),果香浓郁,果肉细腻,糖度高,口感好。为了明确“香粉3号”蕉的果实品质优势,以“香粉1号”蕉为对照,在断蕾后15、25、45、85(青熟)、88 d(完熟)等5个时期测定比较两个品种可溶性糖、可滴定酸、维生素C、总黄酮、色氨酸含量,以及超氧化物歧化酶、过氧化氢酶、过氧化物酶和苯丙氨酸解氨酶等抗氧化相关酶活性。结果表明,果实生长发育过程中,“香粉3号”果肉的可溶性糖、可滴定酸、维生素C、总黄酮等物质含量均普遍高于“香粉1号”;断蕾后88 d(完熟),“香粉3号”果肉的可溶性糖、维生素C、总黄酮显著高于“香粉1号”(p<0.05),两个品种色氨酸含量无显著性差异;该时期“香粉3号”果肉的过氧化氢酶和过氧化物酶活性显著高于“香粉1号”(p<0.05)。说明“香粉3号”果实品质较优,抗氧化酶活性较强,具有推广潜力。

关键词：香粉3号香粉1号龙牙蕉可溶性糖抗氧化酶活性

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Spatial distribution of soil erosion and its impacts on soil productivity in Songnen typical black soil region

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International Soil and Water Conservation Research 2023年第4期11卷 649-659页

作者： Yun Xie Jie Tang Yan Gao Zhijia Gu Gang Liu xiaoyu ren Department of Geographic Science Faculty of Arts and SciencesBeijing Normal University at ZhuhaiZhuhai519087China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing100875PR China Songliao Water Resources Commission Ministry of Water ResourcesChangchunJilin130021PR China Key Laboratory for Synergistic Prevention of Water and Soil Environmental Pollution School of Geographic SciencesXinyang Normal UniversityXinyang464000PR China

Soil erosion is an important reason for land *** black soil region of Northeast China is the main grain production base in China,however,the black soil productivity in this region is at risk and unsustainable now because there was few soil conservation measures in nearly 100 years of *** assess the impact of erosion on land productivity,both 210 sampling points for ^(137)Cs measurement and 112 sampling points for soil profile features were laid out on cultivated land of Songnen typical black soil region in combination with the 2010 China land use *** current soil erosion/deposition rate and land productivity index PI were calculated over the study area,and then the PI values were predicted erosion by 20,50,100,and 200 years without soil and water conservation measures based on the current erosion rate and soil profile *** results showed that the average soil erosion rate of cultivated land in the study area was 705.8 t/(km^(2)·a),and 77.0%of the cultivated land had soil erosion rate larger than the soil loss tolerance of 200 t/(km^(2)·a).Spatially,the soil erosion rate in the northern region was greater than that in the southern region significantly,which was mainly affected by slope *** relationship between soil erosion rate(SL)and slope steepness(θ)in degree was established according to the results of ^(137)Cs measured at 210 sample points:SL=556.4*θ or SL=0.464*θin mm/a(given soil bulk density is 1200 kg/m^(3)).The current mean value of PI for cultivated land was 0.59,decreasing significantly from north to south,which was mainly influenced by organic matter *** predicted PI values decreased significantly with the increase of erosion years in the northern *** is related to the topography of rolling and hills in the northern area with a greater soil loss rate,leading to a rapid decrease of organic matter content and the increase of sand content in the topsoil in the *** spatial distributions

关键词： Soil erosion Land productivity PI model Soil loss rate Black soil region

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山西省资源型城市产业结构及竞争力演进

科技和产业 2024年第12期24卷 179-188页

作者：杨洁任笑雨陈佳宁贾培煜太原师范学院地理科学学院山西晋中030619 太原市外国语学校太原030027 太原师范学院碳中和研究院山西晋中030619

运用产业结构熵、泰尔指数、偏离-份额分析法定量测算2003—2017年山西省资源型城市三次产业的结构、竞争力及其空间分布的演变趋势与特征。结果发现,(1)2003—2017年,阳泉、临汾、运城产业结构趋于多样化,大同等其余七市产业结构趋于... 详细信息

运用产业结构熵、泰尔指数、偏离-份额分析法定量测算2003—2017年山西省资源型城市三次产业的结构、竞争力及其空间分布的演变趋势与特征。结果发现,(1)2003—2017年,阳泉、临汾、运城产业结构趋于多样化,大同等其余七市产业结构趋于专业化;大同、阳泉、运城产业结构合理化水平降低,长治等七市产业结构趋于合理化;除了吕梁市,其余九个资源型城市产业结构均趋于高级化。(2)从三次产业结构与竞争力发展水平上看,第一、二产业发展呈恶化趋势,第一产业的双劣势区域显著扩大,第二产业的双优势区域显著缩小;第三产业发展呈向好趋势,双劣势区域显著缩小。最后,从政府政策层面及各资源型城市发展特点角度,对资源型城市提升产业竞争力和转型发展提升提出对策。

关键词：产业结构产业竞争力资源型城市偏离—份额分析法山西省

Stereodivergently asymmetric synthesis of chiral phosphorus compounds by synergistic combination of ion-pair catalyst and base

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Science China Chemistry 2022年第12期65卷 2500-2511页

作者： Hui-Lin Hu xiaoyu ren Jiajia He Lixiang Zhu Siqiang Fang Zhishan Su Tianli Wang Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu610064China

Stereodivergently constructing the designed products having adjacent multi-stereocenters via a given reaction,with excellent control of both absolute and relative configurations,presents one of the substantial hurdles in asymmetric ***,we report a precisely stereodivergent asymmetric protocol by synergistic combination of phosphonium-involved ion-pair catalysis and base for accessing to chiral phosphorus compounds bearing two adjacent chiral centers particularly containing an acidic protonated enantioenriched carbon atom,having broad functional group compatibility in both dynamic and thermodynamic processes under mild reaction *** keys for the success in constructing these stereoisomers with high levels of regio-,diastereo-,and enantioselectivities were contained:firstly,the precise stereo-control in providing dynamic products was enabled by bifunctional phosphonium salt catalyst with semi-enclosed cavity;secondly,the readily stereospecific transformation of adducts from dynamic to thermodynamic version was initiated by achiral *** four stereoisomers could be readily accessed even in gram-scale in high yields with maintaining excellent stereoselectivities,illustrating the potential of this synergistic catalytic methodology in organic ***,mechanistic studies including density functional theory(DFT)calculations and control experiments provide insights into the mechanism.

关键词： stereodivergent asymmetric synthesis chiral phosphorus compounds dipeptided phosphonium salts cooperative catalysis base control

贵阳市某三甲医院妇产科医护人员加速康复外科知信行现状及讲座的干预效果

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贵州医科大学学报 2024年第1期49卷 115-120页

作者：赵文文杨涵琳任小玉朱焱訾聃贵州医科大学公共卫生与健康学院贵州贵阳550025 贵州省人民医院妇科贵州贵阳550000

目的了解贵阳市某三甲医院妇产科医护人员加速康复外科(ERAS)知信行现状,探讨讲座在改善妇产科医护人员加速康复知信行中的效果。方法以贵阳市某三甲医院妇产科146名医护人员为研究对象,自行设计调查问卷,计算问卷各维度得分评价调查... 详细信息

目的了解贵阳市某三甲医院妇产科医护人员加速康复外科(ERAS)知信行现状,探讨讲座在改善妇产科医护人员加速康复知信行中的效果。方法以贵阳市某三甲医院妇产科146名医护人员为研究对象,自行设计调查问卷,计算问卷各维度得分评价调查对象ERAS知信行状态,采用单因素方差分析妇产科医护人员ERAS知信行得分;对妇产科医护人员进行1次讲座形式的知识宣教,比较讲座前后妇产科医护人员ERAS知信行得分变化情况。结果讲座前妇产科医护人员加速康复外科知识得分较低,得分率仅为65.74%;单因素方差分析和独立样本t检验显示,研究对象知信行得分在学历、年龄、科室、职称、工作年限方面比较,差异有统计意义(P<0.05);讲座后妇产科医护人员加速康复外科知信行整体得分及知识、态度、行为各项单独得分均较讲座前提高(P<0.05)。结论妇产科医护人员加速康复外科知识得分较低,对妇产科医护人员进行讲座形式的培训后,可有效提高医护人员的知信行状况。

关键词：加速康复外科妇产科知识态度行为讲座

On Water： Free Catalysis Approach for the Synthesis of Nitrones from Hydroxamic Acids and Dimethy/ Diethyl Acetylenedicarboxylate

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Chinese Journal of Chemistry 2013年第8期31卷 1003-1006页

作者： Jian Li Yongqin He xiaoyu ren Xiaokang Shi Sizhuo Yang Xiai Gao Guosheng Huang Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000 China Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province Lanzhou Gansu 730000 China

Benzohydroxamic acid reacts with dimethyl acetylenedicarboxylate in the presence of 10 mol% NaOAc to gen- erate （E）-N-（1,4-dimethoxy-l,4-dioxobutan-2-ylidene）-l-phenylcarboxamide oxide in good-to-excellent yield in water at room temperature for 2 h, which supplies a simple, efficient and environmentally friendly method to syn- thesize a wide range of nitrones. The benefits of this strategy not only conform to the requirment of green chemisty, but also possess atom economy.

关键词： nitrones benzohydroxamic acid dimethyl acetylenedicarboxylate environmentally friendly greenchemisty