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沈阳工业学院学报 2003年第1期22卷 23-25页

作者：陈亮杨康张大伟沈阳工业学院信息科学与工程分院辽宁沈阳110016

提出了一种基于灰度偏差匹配的快速高效地查询指纹信息的方法 ,该方法在匹配速度上相对于基于特征点匹配的方法在单点匹配上要快至少两倍以上 .

关键词：指纹识别特征向量灰度匹配

Analysis of the anti-T2DM components in dichloromethane fraction of Schisandra sphenanthera and its mechanism

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Traditional Medicine Research 2025年第1期10卷 27-43页

作者： Shi-Bo Feng Hai-Hui Jiang Hui-Li kang Yi Jiang Hua-Wei zhang Xiao-Mei Song Yu-Ze Li Wen-Li Huang Dong-Dong zhang Chong Deng School of Pharmacy Shaanxi University of Chinese MedicineXianyang 712046China School of Pharmacy and Shaanxi Qinling Application Development and Engineering Center of Chinese Herbal Medicine Shaanxi University of Chinese MedicineXianyang 712046China Key Laboratory for Research and Development of“Qin Medicine”of Shaanxi Administration of Traditional Chinese Medicine Xianyang 712046China Shaanxi Key Laboratory of Research and Application of“Taibai Qi Yao” Xianyang 712046China

Background:The type 2 diabetes mellitus(T2DM)pharmacodynamic study of various parts of Schisandra sphenanthera was conducted in the previous stage,and it was found that dichloromethane extracted part(SDP)had a significant hypoglycemic ***,the components of SDP were analyzed,and the specific mechanism of its anti-T2DM was ***:We used a high-fat,high-sugar diet in combination with streptozotocin to induce a T2DM rat model,and the model rats were divided into two groups according to body weight and blood ***,oral glucose tolerance test,fasting blood glucose,low density lipoprotein cholesterol,superoxide dismutase,insulin,glycated hemoglobin,total cholesterol,nonesterified free fatty acids,alanine aminotransferase,high-density lipoprotein cholesterol,aspartate aminotransferase,malondialdehyde,and glutathione peroxidase were measured,organ indices were calculated,and pathological sections of pancreas and liver were *** 16S rRNA V3–V4 region of intestinal flora was sequenced to explore the effect of SDP on biochemical indicators and intestinal *** on the above indicators,the anti-T2DM mechanism of SDP in Schisandra sphenanthera was ***:After six weeks of administration,the biochemical indices of diabetic rats were diminished compared to the control *** SDP could significantly increase the gut microbialα-diversity index,resulting in significant changes in the flora of T2DM rats,with increased richness and diversity,reduced harmful flora,and significantly back-regulated the levels of acetic acid,propionic acid,and butyric ***:SDP can improve the symptoms associated with elevated blood glucose,dyslipidemia,elevated fasting insulin levels,and damaged glucose tolerance in *** against T2DM may be through the control of intestinal flora to normalize and exert anti-diabetic effect;its main active components may be lignans and terpenoids.

关键词： Schisandra sphenanthera T2DM intestinal flora HPLC

真空预冷压强对鲜枸杞SOD酶活性的影响及分子动力学模拟

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食品工业科技 2025年第1期46卷 54-60页

作者：张宏博康宁波周良欢张军瞿前进宁夏大学食品科学与工程学院宁夏银川750021

为探究真空预冷处理对鲜枸杞超氧化物歧化酶(superoxide dismutase,SOD)活性的影响及其分子水平机理,本研究将宁夏新鲜枸杞置于真空预冷900、1100 Pa压强下处理,提取粗酶液进行SOD酶活性测定,并进行150 ns分子动力学模拟研究SOD酶在不... 详细信息

为探究真空预冷处理对鲜枸杞超氧化物歧化酶(superoxide dismutase,SOD)活性的影响及其分子水平机理,本研究将宁夏新鲜枸杞置于真空预冷900、1100 Pa压强下处理,提取粗酶液进行SOD酶活性测定,并进行150 ns分子动力学模拟研究SOD酶在不同真空预冷压强处理下的内部变化,分析均方根误差、回旋半径、总能量、势能、动能、键角能、均方根涨落、氢键数量、表面结构、溶剂可及表面积的改变,进而筛选出真空预冷处理的最佳压强条件。结果显示,900 Pa处理下SOD酶活最高。分子动力学模拟结果表明,体系总能量、势能、动能及键角能均处于平衡稳定状态,压强增大使得蛋白质表面结构改变,氢键数量减少,溶剂可及表面积不断减小。在900 Pa处理下,蛋白质结构最紧密,活性口袋变宽且易与蛋白结合。而1100 Pa处理下酶蛋白活性降低,蛋白结构破坏,活性口袋变小。本研究可为研究鲜枸杞保鲜及加工提供科学参考。

关键词：枸杞真空预冷超氧化物歧化酶分子动力学模拟

ECD spectrometric methods for detecting the enantioselective enzymatic hydrolysis of racemic 3-acetoxy-4-phenyl-β-lactam

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Chinese Chemical Letters 2012年第10期23卷 1197-1200页

作者： Xiang zhang Li Li Yi kang Si da Li Yin Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation Institute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

（-）-（3R, 4S）-3-Acetoxy-4-phenylazetidin-2-one （（-）-1） was the key intermediate for preparing optical C-13 side-chain moiety in partial synthesis of docetaxel and paclitaxel. It can be successfully prepared via enantioselective hydrolysis of racemic esters （（-4-）-1） catalyzed by bacterial lipases, but the current reaction evaluation method is tedious and inconvenient. Electronic circular dichroism （ECD） has been widely applied in the stereochemical study of chiral compounds. In this paper, a rapid ECD spectroscopic method has been proposed and established to detect the transformation directly. The absolute configurations of lipase-catalyzed hydrolysis products have also been confirmed by quantum-chemical calculation using time-dependent density functional theory （TDDFT） methodology.

关键词： ECD spectroscopy Evaluation method Absolute configuration Time-dependent density functional theory

激光诱导荧光技术与地下水重金属原位检测应用进展

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岩矿测试 2025年第1期44卷 19-34页

作者：毛康薛家奇陈卓张华中国科学院地球化学研究所环境地球化学国家重点实验室贵州贵阳550081

对地下水重金属污染进行现场检测,是快速识别重金属种类和评价污染程度的重要手段。激光诱导荧光技术(LIF)利用特定荧光探针,在目标重金属存在下,通过激光诱导荧光探针产生/猝灭荧光,从而完成对重金属的识别和检测,具有快速甄别地下水... 详细信息

对地下水重金属污染进行现场检测,是快速识别重金属种类和评价污染程度的重要手段。激光诱导荧光技术(LIF)利用特定荧光探针,在目标重金属存在下,通过激光诱导荧光探针产生/猝灭荧光,从而完成对重金属的识别和检测,具有快速甄别地下水重金属污染特性和无损获取其价态的优势。本文在简述LIF检测重金属原理和LIF原位检测地下水重金属装备基础上,重点从荧光探针合成及其在重金属传感检测方法的构建上总结了基于不同荧光探针的LIF现场检测重金属的研究进展。目前可用于重金属检测的荧光探针包括以小分子探针、有机大分子和聚集诱导发光为主的有机荧光探针和以金纳米簇、量子点和金属有机框架材料为代表的纳米荧光探针。这些探针的合成及其对应的传感检测方法的构建表明LIF技术在地下水重金属检测中具有巨大优势。而针对地下水重金属检测的LIF设备研发方面的成果虽不如荧光传感检测方法丰富,但已研制出部分重金属的传感器和检测装备,表现出良好的应用前景。未来研究将会聚焦在地下水重金属主控因子识别和抗干扰技术研发、荧光探针合成与LIF检测方法构建、重金属传感部件和检测装备集成研制,以及检测技术标准化,为后续场地地下水典型重金属LIF检测技术的研究提供参考。

关键词：地下水重金属激光诱导荧光荧光探针现场检测

Oscillating Frequency Response of a Langasite Crystal Microbalance in Liquid Phase

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Chinese Chemical Letters 2005年第11期16卷 1547-1550页

作者： Qi kang Huai Jin zhang Xue Yong LIU da Zhong SHEN School of Chemistry and Chemical Engineering Shandong University Jinan 250100 State Key Laboratory of Crystal Materials Shandong University Jinan 250100

The frequency responses of a langasite crystal microbalance （LCM） in liquid phase were investigated. It was shown that the LCM possessed much stronger oscillating ability in liquid phase than that of the commonly used quartz crystal microbalance （QCM）. The frequency shifts of the LCM to the changes in mass loading, as well as viscosity and density of the liquid were measured. The LCM was applied to monitor the adsorption process of an ionic liquid film to ethanol vapor.

关键词： Piezoelectric sensor langasite crystal frequency response ionic liquid.

Analyzing the response of a contactless conductivity detector in capillary electrophoresis by a resonant method

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Chinese Chemical Letters 2012年第7期23卷 831-834页

作者： Qi kang Qing zhang Yao Long Li Dong Dong Li da Zhong Shen The Key Lab in Molecular and Nano-Materials Probes of the Ministry of Education of China School of ChemistryChemical Engineering and Material ScienceShandong Normal UniversityJinan 250014China

We report a resonant method to measure the wall capacitance（C_w） and solution resistance（R_S） in a capacitively coupled contactless conductivity detector（C^4D）.Under the typical operating conditions in capillary electrophoresis（I.D.50μm,O.D. 360μm,electrode length of 4 mm,electrode gap of 1 mm,frequency of 200 kHz）,the values of C_w measured in 1 and 20 mmol/L NaCl solutions are 2.8 and 32 fF,which are only 1.1%and 12%of prediction by the equation in references,*** value of R_S is less than the prediction in solutions withκ〈0.02 S/*** response current of C^4D is due to the change in C_w because the total impedance of a C^4D is composed mainly by the impedance from C_w.

关键词： Contactless conductivity detector Equivalent circuit parameter Quartz crystal resonator Resonant method

Characteristics of carbonaceous aerosols analyzed using a multiwavelength thermal/optical carbon analyzer: A case study in Lanzhou City

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Science China Earth Sciences 2019年第2期62卷 389-402页

作者： Yulan zhang Shichang kang State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environmental Resources Chinese Academy of Sciences Geoscience Innovation and Innovation Center of the Tibetan Plateau Chinese Academy of Sciences University of Chinese Academy of Sciences

Characteristics of atmospheric carbonaceous aerosols in Lanzhou City from December 2014 to November 2015 are analyzed using a multiwavelength thermal/optical carbon analyzer. Results reveal that average concentrations of black carbon (BC) and organic carbon in atmospheric aerosols at Lanzhou are 6.7 and 25.4 μg m^(-3), respectively, showing obvious seasonality (higher in winter and lower in summer). This is consistent with findings in cities of northern China. Primary organic aerosols and secondary organic aerosols respectively account for approximately 60% and 17% of carbonaceous aerosols. No significant seasonality is found for secondary organic carbon, indicating that its potential sources do not vary significantly throughout the study period. The mass absorption cross-section (MAC_(632nm)) of BC is 7.1 m^2g^(-1), slightly higher than that of immediately emitted BC. MAC values of BC at different wavelengths vary drastically; they are higher for ultraviolet and visible light (8.5–10.2 m^2g^(-1)) than for near-infrared light (4.9–5.7 m^2g^(-1)). The aerosol absorption optical depth generally declines from the near-infrared to the near-ultraviolet region. The values are higher in winter than in summer, thus showing there are different contributions of BC deposition in different seasons. Brown carbon (BrC) has an ?ngstr?m absorption exponent (AAE) value of approximately 2.75, which is similar to the AAE value of BrC generated by diesel combustion (2.3). The contribution of BrC to light absorption is as much as 34% at a wavelength of 635 nm. This study demonstrates that the multiwavelength thermal/optical carbon analyzer can quantify absorption properties of BrC in atmospheric aerosols. This can enhance understanding of carbonaceous aerosols and provide key parameters for simulations of climate models.

关键词： Carbonaceous aerosol Black carbon Organic carbon Brown carbon Multiwavelength thermal/optical carbon analyzer

Apparel Brand Overlap Based on Customer Perceived Value and Eye-Tracking Technology

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Tsinghua Science and Technology 2018年第1期23卷 47-64页

作者： Lei Jiang kang zhang School of Computer Software Tianjin University Tianjin 300350 China Institute of Art and Fashion Tianjin Polytechnic University Tianjin 300387 China

Competition in the apparel market has developed from preliminary price competition, quality competition, and scale competition to the current state of brand competition. The phenomenon of brand overlap cannot be avoided by apparel enterprises during the process of building and manufacturing their brands. This paper has selected nine identification elements of three dimensions, which we used to construct an apparel brand overlap identification model. This model is based on the theories of customer perceived value and brand identity and was constructed by taking consumer perspectives as the starting point. Two apparel brands from the representative international E Company have been selected as our empirical research objects. An apparel brand overlap identification model has been constructed based on questionnaire analysis and a cognitive experiment involving eye-tracking technology. In addition, the overlap elements among apparel brands, as well as the cognitive situation of consumers with regard to brand overlap, have been analyzed.

关键词： eye-tracking technology customer perceived value brand overlap brand identity apparel brand

Existence and Regularity of Solution to the Generalized Tricomi Equation with a Singular Initial datum at a Point

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Acta Mathematica Sinica,English Series 2012年第6期28卷 1135-1154页

作者： kang Qun zhang Department of Mathematics&IMS Nanjing University

In this paper, we study the existence and regularity of a solution to the initial datum problem of a semilinear generalized Tricomi equation in mixed-type initial datum on the degenerate plane is smooth away from the origin, domain. We suppose that an and has a conormal singularity at this point, then we show that in some mixed-type domain, the solution exists and is conormal with respect to the characteristic conic surface which is issued from the origin and has a cusp singularity.

关键词： Generalized Tricomi equation confluent hypergeometric function existence conormalregularity cusp singularity