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Photocatalytic decarboxylative alkylations of C(sp^(3))–H and C(sp^(2))–H bonds enabled by ammonium iodide in amide solvent

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Science China Chemistry 2021年第3期64卷 439-444页

作者： guang-Zu Wang Ming-chen fu Bin Zhao Rui Shang Department of Chemistry University of Science and Technology of ChinaHefei 230026China Department of Chemistry School of ScienceThe University of Tokyo7-3-1 HongoBunkyo-kuTokyo 113-0033Japan

A simple ammonium iodide salt in amide solvent catalyzes regioselective decarboxylative alkylation of C(sp^(3))-H bonds of Naryl glycine derivatives, of C(sp^(2))-H bond of heteroarenes, and cascade radical addition to unsaturated bond followed by intramolecular addition to arene, with a broad scope of N-hydroxyphthalimide derived redox active esters under visible light irradiation. The reactions are suggested to proceed through photoactivation of a transiently assembled chromophore from electron-deficient phthalimide moiety and iodide anion through an anion-π interaction in solvent cage followed by diffusion to generate solvated free radical species to react with C-H substrates. The simplicity, practicality, and broad substrate scope of this method highlight the synthetic power of photocatalysis through transiently assembled chromophore, and will hopefully inspire further developments of low cost photocatalysis based on various non-covalent interactions, which are prevalent in supramolecular chemistry and biosystems, for sustainable organic synthesis.

关键词： decarboxylative alkylation transiently assembled chromophore anion-πinteraction ammonium iodide solvent cage

[Solid-phase extraction coupled with high performance liquid chromatography-triple quadrupole mass spectrometry for simultaneous determination of seven coumarins in water samples from drinking water treatment plants]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 78-86页

作者： Wen-Mei Jiao Jing-Ming Yang Ce Xu fu-Kang Gao Lu-Yao Shen Yu-Bo Yuan Zhi-Fen Guo guang Huang School of Life Sciences and Chemical Engineering Jiangsu Second Normal University Nanjing 211200 China. School of Stomatology Nanjing Medical University Nanjing 210029 China. School of Public Health Nanjing Medical University Nanjing 211166 China. Key Laboratory of Modern Toxicology Ministry of Education School of Public Health Nanjing Medical University Nanjing 211166 China.

Chlorinated coumarins, which are as cytotoxic as highly toxic halobenzoquinones toward CHO-K1 cells, have recently been identified as disinfection byproducts in drinking water disinfection processes. Therefore, detecting coumarins in water samples collected at various stages from drinking water treatment plants helps assess the formation of chlorinated coumarins in drinking water. Hence, a simple, rapid, accurate, and sensitive method for quantifying coumarins in water samples is required. In this study, a method was developed based on solid-phase extraction coupled with high performance liquid chromatography-triple-quadrupole mass spectrometry for analyzing seven coumarins in water samples from drinking water treatment plants, including 6,7-dihydroxycoumarin, 7-hydroxycoumarin, 6-hydroxy-4-methylcoumarin, 8-chloro-7-hydroxycoumarin, coumarin, 7-chloro-6-hydroxy-4-methylcoumarin, and 3,8-dichloro-7-hydroxycoumarin. Sample pretreatment involved solid-phase extraction using HLB columns, followed by elution with water and methanol, each containing 0.25% formic acid. The extracted solution was separated via gradient elution using a Phenomenex Luna C18 column (100 mm×2.0 mm, 3 mm) with 0.1% formic acid aqueous solution and methanol as the mobile phases, with analytes detected by triple-quadrupole mass spectrometry equipped with electrospray ionization source in multiple reaction monitoring mode. The matrix effect, precision, and accuracy of the developed method were investigated using raw and treated water as matrices. Matrix effects of 0.84-1.12 were recorded for the detection of 6,7-dihydroxycoumarin, 7-hydroxycoumarin, 6-hydroxy-4-methylcoumarin, and coumarin in raw water, while values of 0.67-0.70 were recorded for 8-chloro-7-hydroxycoumarin, 7-chloro-6-hydroxy-4-methylcoumarin, and 3,8-dichloro-7-hydroxycoumarin in finished water. The three chlorinated coumarins exhibited matrix effects above 0.80 after the finished water matrix had been diluted four times. These re

关键词： coumarins disinfection byproducts drinking water high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) solid-phase extraction (SPE)

The Possible Effect of Climate Warming on Northern Limits of Cropping System and Crop Yield in China

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Agricultural Sciences in China 2011年第4期10卷 585-594页

作者： YANG Xiao-guang LIU Zhi-juan chen fu College of Resources and Environmental Sciences China Agricultural University Beijing 100193 P.R. China College of Agronomy and Biotechnology China Agricultural University Beijing 100193 P.R.China

Significantly increasing temperature since the 1980s in China has become a consensus under the background of global climate change and how climate change affects agriculture or even cropping systems has attracted more and more attention from Chinese government and scientists. In this study, the possible effects of climate warming on the national northern limits of cropping systems, the northern limits of winter wheat and double rice, and the stable-yield northern limits of rainfed winter wheat-summer maize rotation in China from 1981 to 2007 were analyzed. Also, the possible change of crop yield caused by planting limits displacement during the periods 1950s-1981 and 1981-2007 was compared and discussed. The recognized calculation methods of agricultural climatic indices were employed. According to the indices of climatic regionalization for cropping systems, the national northern limits of cropping systems, winter wheat and double rice, and the stable-yield northern limits of rainfed winter wheat-summer maize rotation during two periods, including the 1950s-1980 and 1981-2007, were drawn with ArcGIS software. Compared with the situation during the 1950s- 1980, the northern limits of double cropping system during 1981-2007 showed significant spatial displacement in Shaanxi, Shanxi, Hebei, and Liaoning provinces and Beijing municipality, China. The northern limits of triple cropping system showed the maximum spatial displacement in Hunan, Hubei, Anhui, Jiangsu, and Zhejiang provinces, China. Without considering variety change and social economic factors, the per unit area grain yield of main planting patterns would increase about 54-106% if single cropping system was replaced by double cropping system, which turned out to be 27- 58% if double cropping system was replaced by triple cropping system. In Liaoning, Hebei, Shanxi, Shaanxi, Gansu, and Qinghai provinces, Inner Mongolia and Ningxia autonomous regions, China, the northern limits of winter wheat during 1981-200

关键词： climate warming the northern limits of cropping system the planting northern limits of winter wheat the planting northern limits of double rice crop yield

2型猪链球菌SsU05-0474的表达纯化及单克隆抗体制备

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中国动物传染病学报 2016年第2期24卷 25-30页

作者：杨宝玲陈福广谢芳刘思国沈国顺张跃灵沈阳农业大学畜牧兽医学院沈阳110866 中国农业科学院哈尔滨兽医研究所兽医生物技术国家重点实验室哈尔滨150001

为了鉴定2型猪链球菌(Streptococcus suis serotype 2,Ss2)菌毛骨架蛋白Ss U05-0474(本文中简称SsMps)在菌体中的位置和存在形式,本研究以2型猪链球菌05ZYH33菌株基因组作为模板,PCR扩增菌毛骨架蛋白基因Ss U05-0474,将其克隆至表达载体... 详细信息

为了鉴定2型猪链球菌(Streptococcus suis serotype 2,Ss2)菌毛骨架蛋白Ss U05-0474(本文中简称SsMps)在菌体中的位置和存在形式,本研究以2型猪链球菌05ZYH33菌株基因组作为模板,PCR扩增菌毛骨架蛋白基因Ss U05-0474,将其克隆至表达载体pET22b,构建重组质粒pET22b/SsMps,转化至*** BL21(DE3)中,用IPTG诱导表达SsMps蛋白,并通过亲和层析纯化。纯化的SsMps蛋白免疫BALB/c雌鼠,利用细胞融合筛选制备该重组蛋白的单克隆抗体。结果显示,SsMps蛋白在大肠杆菌中以可溶形式表达,分子质量大小为45 k Da。每升大肠杆菌培养物可获得SsMps重组蛋白约30 mg,纯度大于95%。获得了1株该重组蛋白的单克隆抗体1D9,抗体亚型为IgG1/κ。通过单抗1D9与05ZYH33菌体蛋白组分Western blot,发现该抗体能够特异识别SsMps,并定位出SsMps大部分存在于细胞壁蛋白成分中,呈不同聚体存在。本研究制备的SsMps纯化蛋白及其单克隆抗体为研究SsMps蛋白的功能提供了工具。

关键词： 2型猪链球菌 Ss Mps基因蛋白表达蛋白纯化单克隆抗体

Fast-growing forest pruning robot structure design and climbing control

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Advances in Manufacturing 2015年第2期3卷 166-172页

作者： guang-Hua fu Xue-Mei Liu Yan-fu chen Jin Yuan School of Mechanical and Electronic Engineering Shandong Agricultural University Shandong Provincial Key Laboratory of Horticultural Machinery and Equipment

According to the requirement of fast-growing forest pruning operation, the pruning robot was developed. The structure and control system of pruning robot were described, the work flow of pruning robot was expounded. The type and structure of the driving motor and the compression spring were decided with force-balance analysis. The tilt problem of pruning robot was resolved by ADAMS and Matlab co-sim- ulation, and the control scheme of climbing mechanism was determined. The experiment results of the prototype indicate that pruning robot can climb tree trunk smoothly at a speed of 20 mm/s and cross the raised trunk. The pruning saw which is driven by the adjustable speed motor can cut the branches of 30 mm. And the residual amount of branches is less than 5 mm. Pruning robot can meet the practical requirements of the fast-growing forest pruning work.

关键词： Fast-growing forest - Pruning robot Structure - Co-simulation

Performance of a single-stage Linde-Hampson refrigerator operating with binary refrigerants at the temperature level of-60°C

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第2期11卷 115-127页

作者： Qin WANG Kang CUI Teng-fei SUN fu-sheng chen guang-ming chen State Key Laboratory of Clean Energy Utilization Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

The optimization of the performance of a single-stage Linde-Hampson refrigerator （LHR） operating with six different binary refrigerants （R23/R134a, R23/R227ea, R23/R236ea, R170/R290, R170/R600a and R170/R600） with ozone depletion potentials （ODPs） of zero was conducted using a new approach at the temperature level of-60℃. Among these binary refrig- erants, the 0.55 and the 0.6 mole fractions of R23 for R23/R236ea are the most prospective nonflammable ones for the medium and low suction pressure compressors, respectively. For these two kinds of compressors, the 0.6 and the 0.65 mole fractions of R170 for R 170/R600, respectively, are the most prospective binary refrigerants with low global warming potentials （GWPs）. The results of optimization of pressure levels indicate that the optimum low pressure value for coefficients of performance （COP） is achieved when the minimum temperature differences occur at both the hot and the cold ends of the recuperator at a specified composition and pressure ratio. Two useful new parameters, the entropy production per unit heat recuperated and the ratio of heat recuperating capacity to the power consumption of the compression, were introduced to analyze the exergy loss ratio in the recuperator. The new approach employed in this paper also suggests a promising application even to the optimization of the performance with multi-component refrigerants.

关键词： Linde-Hampson Binary refrigerant Refrigerator Performance Optimization

First-Principle Calculations for Elastic and Thermodynamic Properties of Diamond

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Communications in Theoretical Physics 2009年第6期51卷 1129-1134页

作者： fu Zhi-Jian JI guang-fu chen Xiang-Rong GOU Qing-Quan Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China Laboratory for Shock Wave and Detonation Physics Research Institute of Fluid Physics Chinese Academy of Engineering Physics Mianyang 621900 China International Centre for Materials Physics Chinese Academy of Sciences Shenyang 110016 China

The elastic constants and thermodynamic properties of diamond are investigated by using the CRYSTALO3 program. The lattice parameters, the bulk modulus, the heat capacity, the Gruneieen parameter, and the Debye temperature are obtained. The results are in good agreement with the available experimental and theoretical data. Moreover, the relationship between V/V0 and pressure, the elastic constants under high pressure are successfully obtained. Especially, the elastic constants of diamond under high pressure are firstly obtained theoretically. At the same time, the variations of the thermal expansion α with pressure P and temperature Tare obtained systematically in the ranges of 0-870 GPa and 0-1600 K.

关键词： density functional theory elastic constants thermodynamic properties diamond

紫外线消毒系统中超声波抑垢的机制及参数优化

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土木与环境工程学报（中英文） 2025年第1期47卷 221-228页

作者：陈光赵志伟李莉重庆大学环境与生态学院重庆400045

紫外消毒技术因具有无须投加化学药剂、消毒广谱性、产生副产物少等优势越来越受重视,但石英套管结垢引起的消毒效果难以保障,成为限制紫外消毒技术发展的瓶颈。在污水厂紫外线消毒渠中搭建中试试验装置,利用超声波抑制石英套管结垢,结... 详细信息

紫外消毒技术因具有无须投加化学药剂、消毒广谱性、产生副产物少等优势越来越受重视,但石英套管结垢引起的消毒效果难以保障,成为限制紫外消毒技术发展的瓶颈。在污水厂紫外线消毒渠中搭建中试试验装置,利用超声波抑制石英套管结垢,结果表明,超声波能通过延长结垢诱导期来抑制垢的生成;以相对紫外线强度为考察对象,通过单因素试验确定超声波功率、清洗周期、超声时间合适的范围分别在500~1000 W、0.5~1.0 d、20~40 min;对于使用时间为0、0.5、1、3、5 a的石英套管,超声波均有很好的抑垢效果。为了进一步优化参数,采用Box-Behnken设计法和响应面分析方法对主要因素加以优化,得到了响应面回归模型和最优解。结果表明,超声波技术抑垢清垢的优化工艺参数为超声波功率P=965 W,清洗周期T=0.5 d,超声时间t=34 min,预测相对紫外线强度最大值为1.01。通过统计学检验,模型具有良好的拟合性,在优化工艺条件下得到的相对紫外线强度预测值与试验值接近,误差为1.00%。

关键词：超声波紫外线消毒石英套管结垢响应面法

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非厄米PT对称多通道光波导体系的调控及动力学

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原子与分子物理学报 2025年第1期42卷 108-117页

作者：孙武叶伏秋张光成吉首大学物理与机电工程学院吉首416000

宇称-时间(PARITY-TIME PT)对称光学波导系统中有关PT对称性的调控主要通过周期性变化的复折射率材料来实现.本文中我们给出了一种对于已耦合的双通道波导体系中额外引入周期调制的中性波导操纵PT对称性的构型,通过高频近似将系统转换... 详细信息

宇称-时间(PARITY-TIME PT)对称光学波导系统中有关PT对称性的调控主要通过周期性变化的复折射率材料来实现.本文中我们给出了一种对于已耦合的双通道波导体系中额外引入周期调制的中性波导操纵PT对称性的构型,通过高频近似将系统转换为重整化参数后的等效未调制系统后,发现可以通过额外引入单频周期调制的光波导去调控体系的PT对称性,并且讨论了周期调制的非厄米三通道波导体系的能谱特性.最后通过解析和数值的方法给出了光在非厄米三通道光学波导中的动力学演化.

关键词： PT对称非厄米三通道波导