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Microwave-assisted base-free synthesis of trans-cinnamic acids using hypervalent iodonium salts

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Chinese Chemical Letters 2007年第3期18卷 272-274页

作者： min Zhu Chao Shentu Zhong Shi Zhou College of Biological and Environmental Sciences Zhejiang Shuren University Hangzhou 310015 China

A fast and convenient base-free Heck reaction of acrylic acid with hypervalent iodonium salts was achieved under microwave irradiation in water, providing a simple method for the synthesis of trans-cinnanfic acids in ... 详细信息

关键词： Heck reaction Hypervalent iodonium salts Microwave irradiation trans-Cinnamic acids

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基于最小二乘支持向量机的模糊时序分析方法

浙江大学学报（工学版） 2005年第8期39卷 1142-1146页

作者：沈斌姚敏易文晟浙江大学计算机科学与技术学院浙江杭州310027

利用最小二乘支持向量机良好的分类和函数估计能力,提出了一种新的模糊时序分析方法.该方法包括两部分:在模糊时序处理部分通过建立启发式规则、模糊变量、论域、模糊集合和隶属度函数,完成历史数据的模糊化;最小二乘支持向量机处理部... 详细信息

利用最小二乘支持向量机良好的分类和函数估计能力,提出了一种新的模糊时序分析方法.该方法包括两部分:在模糊时序处理部分通过建立启发式规则、模糊变量、论域、模糊集合和隶属度函数,完成历史数据的模糊化;最小二乘支持向量机处理部分替代传统的模糊关系计算,对模糊化的历史数据进行分析,然后去模糊化得到最后的预测结果.与多种传统模糊时序分析方法的对比试验表明,该方法充分利用了支持向量机较好的推广性能等优点,具有更高的精度和较好的泛化效果.

关键词：模糊时序最小二乘支持向量机模糊逻辑

荧光光谱法和紫外分光光度法在发酵调味品中苯甲酸含量测定中的应用和比较

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中国调味品 2010年第1期35卷 78-80,84页

作者：吴勤民江苏食品职业技术学院江苏淮安223001

对紫外分光光度法和荧光光谱法测定酱油和食醋中苯甲酸含量的方法进行了优化和比较,实验结果表明,荧光光谱最佳发射波长为320 nm,最佳激发波长为225 nm,最佳测定pH为2.6;最优化样品氧化条件为水浴温度为100℃,蒸馏液体积为50 mL,水浴时... 详细信息

对紫外分光光度法和荧光光谱法测定酱油和食醋中苯甲酸含量的方法进行了优化和比较,实验结果表明,荧光光谱最佳发射波长为320 nm,最佳激发波长为225 nm,最佳测定pH为2.6;最优化样品氧化条件为水浴温度为100℃,蒸馏液体积为50 mL,水浴时间为17.5 min;荧光光度法在测定准确度、最低检测限和加标回收率以及检测的方便性都明显优于紫外分光光度法。

关键词：荧光光谱法紫外分光光度法苯甲酸发酵调味品

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发酵豆制品异黄酮含量及其抗氧化活性测定

中国调味品 2009年第8期34卷 109-111,113页

作者：吴勤民江苏食品职业技术学院江苏淮安223001

实验对淡豆豉中异黄酮含量及其抗氧化活性进行了研究,实验结果表明:紫外检测的最佳波长为255nm;测定上限可达到9.0mg/L,下限为0.1mg/L,回收率为99%,RSD为2%;豆豉能显著降低MDA和增加SOD活力,对猪油脂肪有很强的抗氧化作用。

关键词：淡豆豉紫外分光光度法 MDA SOD 抗氧化

Synthesis of porous iron hydroxy phosphate from phosphate residue and its application as a Fenton-like catalyst for dye degradation

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Journal of Environmental Sciences 2022年第2期34卷 307-319页

作者： Weilin Guo yin Cao yi Zhang Lijun Wang Lingxue Kong School of Environmental and Materials Engineering Shanghai Polytechnic UniversityShanghai 200240China Deakin University GeelongInstitutefor Frontier MaterialsVictoria 3216Australia Shanghai Innovation Institutefor Materials Shanghai 200444China

Phosphate residue is a kind of hazardous solid waste and if not properly disposed of, could cause serious environmental contaminations. The abundant iron salt available in phosphate residue can be used to prepare photo-Fenton catalytic reagent for wastewater treatment. In this study, the phosphate residue was effectively purified by a hydrothermal recrystallization method, reaching an iron phosphate purity of 94.2%. The particles of iron phosphate were further processed with ball milling with their average size reduced from 19.4 to 1.6 μm. By hydrothermal crystallization of iron phosphate and thermal decomposition of oxalate precursor, porous iron hydroxy phosphate was prepared. The modified porous iron hydroxy phosphate(m-PIHP) of higher surface area with iron oxalate on its surface can degrade 98.87% of Rhodamine B in 15 min. Cyclic experiment showed that the catalyst still had a good catalytic activity after six cycles( > 40%). The X-ray photoelectron spectroscopy results showed that the iron oxalate complex on the catalyst surface decomposed to produce ferrous ions and accelerated the rate of · OH production. The current work demonstrated that the m-PIHP synthesized from phosphate residue and modified with iron oxalate can be used as an effective dye wastewater treatment agent.

关键词： Phosphate residue Porous iron hydroxy phosphate Fenton-like ·OH

Analysis of American skills and its educational inspiration for Chinese medicine

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Journal of Acute Disease 2017年第2期6卷 53-56页

作者： Yan-min Gao Yan-Qi Hu Chen-Lei Li Xiao-Long qin School of Clinical Medicine Shanghai University of Medicine and Health SciencesShanghai201318China

There are various modes of American pre-hospital emergency with different rescue levels which can meet the needs of out-of-hospital rescue in different environments and grades. Pre-hospital emergency workers are relatively divided into different levels with different requirements of skills and practicing certificates. These sources and training of pre-hospital emergency workers of different levels are independent, totally different from those of medical workers in the hospital. By participating and watching the process of American pre-hospital emergency on the spot, observing and experiencing the classification and education levels of American pre-hospital emergency, analyzing the system of American pre-hospital emergency and their requirements for pre-hospital emergency workers' skills, and comparing with the actual situation of Chinese medicine education, the study showed the training differences between American pre-hospital emergency workers and Chinese pre-hospital emergency workers and their advantages in the hope of enhancing the pertinence of training Chinese pre-hospital emergency workers and providing a new direction for the development of Chinese pre-hospital emergency system from another view.

关键词： American workers Skill Analysis Inspiration

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高校学生档案转递中存在的问题与对策

山西档案 2011年第5期 33-34页

作者：曹勤民山西大学档案馆山西太原030006

高校学生毕业、就业后，安全、及时、准确地将其档案转递给用人单位或者新的档案主管单位，对有效服务用人单位、维护高校毕业生的权益，有着重要的意义。但是，长期以来存在的高校学生档案转递不安全、不及时、不准确的问题，不仅影响... 详细信息

高校学生毕业、就业后，安全、及时、准确地将其档案转递给用人单位或者新的档案主管单位，对有效服务用人单位、维护高校毕业生的权益，有着重要的意义。但是，长期以来存在的高校学生档案转递不安全、不及时、不准确的问题，不仅影响了一些高校毕业生的顺利就业和未来发展，而且还影响对高校毕业生档案的有效保护。因此，必须正确看待高校学生档案转递中存在的问题，分析问题产生的原因，采取相应对策切实加以解决。

关键词：学生档案高校转递存在问题

Concentration of α-Linoleic Acid of Perilla Oil by Gradient Cooling Urea Inclusion

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Agricultural Sciences in China 2009年第6期8卷 685-690页

作者： GU Hai-bo MA Xue-yi WU Jing-bo ZHANG Qi YUAN Wen-bing CHEN yi-ping Key Study Center of the National ministry of Education for Tropical Resources Utilization/Hainan Provincial Key Labortary of Fine Chemistry Haikou 570228 P.R. China State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 P.R.China Department of Chemistry and Chemical Engineering Jiangsu University Zhenjiang 212013 P.R.China

In this study, production of ct-linoleic acid concentrated from crude perilla oil by gradient cooling urea inclusion was optimized. The fatty acid composition was determined after ethyl esterification by gas chromatography （GC）. In this process, orthogonal experiment was carried out. Under optimum conditions, the maximum amount of α-linoleic acid （91.5%） was obtained at a urea to fatty acid ratio of 3, a solvent to fatty acids ratio of 7, a reaction temperature of 348 K and a crystallization time of 690 min. A simple method of gradient cooling urea inclusion was used to purify α-linolenic acid by using urea to form inclusion complexes with the saturated and the less unsaturated fatty acids, which enhanced the purity of α-linoleic acid ethyl ester by above 90%.

关键词： gradient cooling α-linoleic acid urea inclusion fatty acid perilla oil

Effect of Intrinsic Decoherence of Milburn's Model on Entanglement of Two-Qutrit States

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Communications in Theoretical Physics 2008年第2期49卷 516-520页

作者： QIU Liang WANG An-min MA Xiao-San Department of Modern Physics University of Science and Technology of China Hefei 230026. China

We model of intrinsic analyze the time evolution of entanglement of two-qutrit system within the framework of Milburn＇s decoherence. The entanglement evolution relies not only on the parameters of system, but also on the concrete states either pure or mixed. The linear entropy used to measure the extent to which the intrinsic decoherenee affects quantum states is evaluated.

关键词： intrinsic decoherence Milburn's model time evolution of entanglement