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N-Acety-L-Cysteine-Stabilized Pt Nanozyme for Colorimetric Assay of Heparin

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Journal of Analysis and Testing 2019年第3期3卷 277-285页

作者： xinxue li Qingwei Huang Wei li Jinli Zhang Yan Fu School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350People’s Republic of China

N-Acety-L-cysteine(NAC),enriched with multiple electron-rich groups involving-SH,-C=O,and-COOH,exhibits strong affinities to transition metal ***,NAC was adopted as the stabilizing agent to synthesize a series of peroxidase-like Pt nanoclusters(NCs)with different physicochemical *** the cluster size and the charge state of NAC-Pt NCs are highly dependent upon the molar ratio of[K_(2)PtCl_(4)]/[NAC],contributing to different peroxidase mimicking *** most active Pt nanozyme(~1.7 nm),composed of 60%metallic Pt^(0) and 40%positively charged Pt^(2+)respectively,exhibits the K_(m) of 0.132 mM for 3,3′,5,5′-tetramethylbenzidine and 35 mM for H_(2)O_(2).Based on the heparin-activated enzymatic activ-ity of NAC-Pt at pH 6.0,an ultrasensitive test was established for quantitative determination of heparin,giving the linear response of 0.5-20μg/mL as well as the limit of detection of 2×10^(−3)μg/*** proposed method is also applicable in biological fluid for practical *** a colorimetric method possesses several advantages involving high sensitiv-ity,short response,eco-friendly synthesis,low consumption of material and energy,free of expensive instrument,as well as simple operation.

关键词： Biothiol Platinum Nanocluster Peroxidase Colorimetry

Effect of poly(ethylene glycol) molecular weight on CO_2/N_2 separation performance of poly(amide-12-b-ethylene oxide)/poly(ethylene glycol) blend membranes

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Journal of Energy Chemistry 2019年第1期28卷 39-45页

作者： Shichao Feng Jizhong Ren Dan Zhao Hui li Kaisheng Hua xinxue li Maicun Deng State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences

Membranes from block copolymer poly(amide-12-b-ethylene oxide)(Pebax1074) and its blends with different molecular weight poly(ethylene glycol)(PEG)(200, 400, 600, 1500, 4600 and 8000) were prepared. The thermal properties and structures of Pebax1074/PEG blend membranes were characterized by DSC and SEM, and the gas permeation properties of CO_2 and N_2 were also investigated at different temperatures. For Pebax1074/PEG blend membranes with low molecular weight PEG(MW≤ 600), higher gas permeabilities than Pebax1074 were achieved. The permeability increased with the increase of PEG molecular weight. The addition of low molecular weight PEG resulted in decrease in activation energy of permeation. For Pebax1074/PEG blend membranes with high molecular weight PEG(MW≥ 1500), due to the melt of PEO phase crystals, the gas permeation properties of blend membranes were temperaturedependent, which could be divided into crystalline region, transition region and amorphous region according to two different transition temperatures. PEG molecular weight and operation temperature determined different gas permeation properties of Pebax1074/PEG blend membranes in three regions. The activation energies of permeation in crystalline region were larger than those in amorphous region.

关键词： Poly(amide-12-b-ethylene oxide) Polyethylene glycol Blend membrane Carbon dioxide separation

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不同外推方法求解近海风机的极限载荷

上海交通大学学报 2016年第6期50卷 844-848页

作者：李昕雪王迎光上海交通大学船舶海洋与建筑工程学院海洋工程国家重点实验室上海200240

利用时域仿真得到短期载荷,对比了广义极值(GEV)分布方法与基于广义Pareto分布(GPD)的阈值模型求解面外叶根部弯矩极值的差异.结果表明:GEV分布方法忽略了其他分组中较大的样本,造成了数据的较大浪费;而基于GPD的阈值模型可以充分利用... 详细信息

利用时域仿真得到短期载荷,对比了广义极值(GEV)分布方法与基于广义Pareto分布(GPD)的阈值模型求解面外叶根部弯矩极值的差异.结果表明:GEV分布方法忽略了其他分组中较大的样本,造成了数据的较大浪费;而基于GPD的阈值模型可以充分利用数据中的极值信息,考虑了超过某一值的所有数据,可以预测近海风机的面外叶根部弯矩.

关键词：近海风机极限载荷广义极值分布广义Pareto分布

Hydrolysis of Carbonyl Sulfide in Binary Mixture of Diethylene Glycol Diethyl Ether and Water

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Chinese Journal of Chemical Engineering 2005年第2期13卷 234-238页

作者：李新学刘迎新魏雄辉 Department of Applied Chemistry College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

The solubility and hydrolysis of carbonyl sulfide in binary mixture of diethylene glycol diethyl ether and water are studied as a function of composition. The use of an aqueous solution of diethylene glycol diethyl ether enhances the solubility and hydrolysis rate of carbonyl sulfide compared with that in pure water. The composition of the mixture with maximum hydrolysis rate varies with temperature. The thermophysical properties including density, viscosity, and surface tension as a function of composition at 20℃ under atmospheric pressure as well as liquid-liquid equilibrium (LLE) data over the temperature range from 28℃ to 90℃ are also measured for the binary mixture.

关键词： carbonyl sulfide solubility hydrolysis diethylene glycol diethyl ether

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化学与社会课程考核的育人导向探索

大学化学 2019年第11期34卷 27-32页

作者：李新学北京科技大学化学系

以积累化学知识为基础,以提升综合素质为目标,探讨了化学与社会课程考核中强化育人价值的途径。始终贯穿立德树人的理念,采用形成性评价考核方式,在课堂测试、课堂讨论、课堂辩论、实验课开设、论文写作、期末测试等环节,注重培育大学... 详细信息

以积累化学知识为基础,以提升综合素质为目标,探讨了化学与社会课程考核中强化育人价值的途径。始终贯穿立德树人的理念,采用形成性评价考核方式,在课堂测试、课堂讨论、课堂辩论、实验课开设、论文写作、期末测试等环节,注重培育大学生的社会责任感、自主学习能力、实践意识和创新精神。

关键词：化学与社会素质教育考核方式育人导向

基于信号处理技术的光纤激光器脉冲振幅均衡研究

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激光杂志 2022年第3期43卷 134-137页

作者：龙小丽李欣雪覃凤广东理工学院广东肇庆526100

为解决当前光纤激光器脉冲振幅均衡过程中存在的一些难题,提高光纤激光器脉冲振幅均衡精度,提出了基于信号处理技术的光纤激光器脉冲振幅均衡方法研究。首先通过信号重采样技术将光纤激光器脉冲振幅信号变为阶比值固定的信号,然后根据... 详细信息

为解决当前光纤激光器脉冲振幅均衡过程中存在的一些难题,提高光纤激光器脉冲振幅均衡精度,提出了基于信号处理技术的光纤激光器脉冲振幅均衡方法研究。首先通过信号重采样技术将光纤激光器脉冲振幅信号变为阶比值固定的信号,然后根据小波调节方法提取不同阶比分量,最后利用机器学习算法实现光纤激光器脉冲振幅均衡。仿真实验结果表明,所提方法的光纤激光器脉冲振幅均衡延时最高为16 ms,光纤激光器脉冲振幅均衡复杂度平均为0.018%,脉冲能量平均为634 mJ,能够有效获得理想的光纤激光器脉冲振幅均衡结果。

关键词：信号处理技术光纤激光器脉冲振幅均衡实验

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一种测试活性炭吸附性能的新方法

工业水处理 2008年第6期28卷 61-63页

作者：杨健李新学闻人勤上海电力学院上海200090 太仓港环保发电有限公司江苏太仓215433

介绍了一种利用天然水中有机物为标准物测试活性炭吸附性能的测试新方法,其测试结果较好地表征了活性炭在实际水处理中对有机物的吸附性能。

关键词：活性炭天然水有机物吸附

逆向思维法在普通化学稀溶液沸点升高和凝固点降低教学中的应用

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大学化学 2024年第11期39卷 359-364页

作者：李新学北京科技大学化学系北京100083

结合普通化学中稀溶液沸点升高和凝固点降低的教学内容,提出以课程教学为载体,采用逆向思维法,培养大学生的质疑精神、辨析能力、自主学习内生动力、创新意识和探索能力。

关键词：沸点升高凝固点降低逆向思维创新能力

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Density, Viscosity, and Excess Properties for Binary Mixture of Diethylene Glycol Monoethyl Ether ＋ Water from 293.15 to 333.15 K at Atmospheric Pressure

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Chinese Journal of Chemical Engineering 2009年第6期17卷 1009-1013页

作者：李新学徐国民王彦伟胡一江 Department of Chemistry University of Science and Technology Beijing Beijing 100083 China No 4 Oil Production Company Petrochina Daqing Oilfield Daqing 163511 China

Densities and viscosities were measured as a function of composition for binary liquid mixture of diethylerie glycol monoethyl ether [CH3CH2O（CH2）2O（CH2）2OH] ＋ water from 293.15 to 333.15 K at atmospheric pressure, with a capillary pycnometer and Ubbelohde capillary viscometer respectively. From the experimental data, the excess molar volume V^E, viscosity deviation △η, and the excess energy of activation for viscous flow △G^＊E were calculated. These data were correlated by the Redlich-Kister type equations to obtain the coefficients and standard deviations. The results showed a strong molecular interaction between diethylene glycol monoethyl ether and water.

关键词： density viscosity diethylene glycol monoethyl ether binary mixture excess molar volume viscosity deviation