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Studies on the Phase Properties of Winsor Ⅰ-Ⅲ Type Microemulsions with Dielectric Relaxation Spectroscopy

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Chinese Chemical Letters 2005年第9期16卷 1263-1266页

作者： Jin Ling CHAI yan hong gao Kong Shuang ZHAO Gan Zuo LI gao Yong ZHANG Department of Chemistry Shandong Normal University Jinan 250014 Key Laboratory for Colloid and Interface Chemistry of State Education Ministry Shandong University Jinan 250100 Department of Chemistry.Beijing Normal University Beijing 100875

The dielectric relaxation spectroscopy （DRS） of Winsor I -Ⅲ microemulsions for nonionic surfactant octyl polyglucoside CsG1.46/1-butanol/cyclohexanedwater system was studied. The experiment shows that the permittivity decreases with the increase in the frequency and clear dielectric relaxation phenomena were observed. Permittivity obviously decreases with the change of the microstructure of the microemulsion, W/O, B.C. and O/W can be distinguished by the permittivity.

关键词： Phase property microemulsion dielectric relaxation spectroscopy

Effects of cultivation conditions on the diversity of microbes involved in the conversion of rice straw to fodder

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Journal of Environmental Sciences 2007年第1期19卷 67-73页

作者： yanG hong-yan gao Li-juan WANG Xiao-fen WANG Wei-dong CUI Zong-jun College of Agronomy and Biotechnology China Agricultural University Beijing 100094 China

To confirm the optimum cultivation conditions for analyzing lactic acid bacterial communities and to provide the cultivation foundation for lactic acid bacterial communities that were used to convert straw into fodder, fermented rice straw was inoculated into 13 different broths. After 48 h of cultivation, pH values, volatile products, and microbial diversity were analyzed. Except for LAB broth, the pH values of the other broths could decrease to approximately 4.5. GC/MS analysis showed that lactic acid in Tomato MRS broth, MRS broth, LAB broth, and Tomato juice broth was higher than that in the other broths. DNA concentration analysis showed that the counts of microbes in Tomato MRS broth were 2.5 times of those in other broths and that tomato juice favored the reproduction of the microbes. Denaturing gradient gel electrophoresis （DGGE） analysis showed that the number of lactic acid bacterial species in HYA broth, Tomato juice broth, and Tomato MRS broth were higher than those in the other broths.

关键词： straw cultivation condition microbial diversity DGGE

Isolation and Identification of Virus dsRNA from Strawberry Plants

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Agricultural Sciences in China 2007年第1期6卷 86-93页

作者： LI He DAI hong-yan ZHANG Zhi-hong gao Xiu-yan DU Guo-dong ZHANG Xin-yu College of Horticulture Shenyang Agricultural University Shenyang 110161 P.R.China

The analysis of virus genome is based on nucleic acid isolation. The aims of this study were to develop a method for isolation and identification of virus double-stranded ribonucleic acid （dsRNA） and to elucidate the nucleotide sequences of strawberry virus. Using the modified method, virus dsRNA was extracted from strawberry virus indicator plants and cultivated strawberry plants and detected using agarose gel electrophoresis with ethidium bromide staining and reverse transcription-polymerase chain reaction （RT-PCR）. The quantity of virus dsRNA varied among strawberry cultivars. The quantity of dsRNA from in vitro plantlets was higher than that from the young leaves of field plants. For the field-grown plants, there was more dsRNA in the young leaves. Virus dsRNA extracted from strawberry plants was resistant to deoxyribonuclease Ⅰ （DNase Ⅰ）, but evidently, it became resistant to ribonuclease A （RNase A） only in the presence of 0.5 M NaCl. Its bands in agarose gel could be readily recycled using an agarose gel DNA purification kit. With RT-PCR, the segments of both strawberry mottle virus and Strawberry mild yellow edge virus genomes were amplified by using the virus dsRNA recycled from gel or treated with DNase Ⅰ /RNase A as templates. The system developed for dsRNA isolation and identification in strawberry plants laid a sound foundation for the work on genome analysis of strawberry virus isolates in China.

关键词： dsRNA virus strawberry isolation RT-PCR

The Target of Benzimidazole Carbamate Against Cysticerci cellulosae

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Agricultural Sciences in China 2007年第8期6卷 1009-1017页

作者： LI Qing-zhang HAO yan-hong gao Xue-jun gao Wen-xue ZHAO Bing College of Biological Science Northeast Agricultural University Harbin 150030 P.R.China

To study the target of benzimidazole carbamate drugs against Cysticerci cellulosae and give a theoretical basis for type evolution and new drug design, the changes of key enzyme activities and metabolite contents in the pathway of energy metabolism in C. cellulosae in vitro and in vivo were tested with albendazole and oxfendazole, respectively. Both albendazole and oxfendazole inhibited the pathways of anaerobic glycolysis, partial inversed tricarboxylic acid cycle of Taenia Solium oncosphere, immature and mature Cysticerci in vitro, and immature and mature Cysticerci in vivo to a certain degree, and enhanced fat decomposing, amino acid decomposing, xanthine decomposing metabolism, and on the other hand, the absorption of glucose was hindered; furthermore, both albendazole and oxfendazole inhibited the activities of the fumaric reductase （FR） complex noncompetently in vitro. Benzimidazole carbamate drugs could inhibit the activities of FR complex noncompetently and hinder the absorption of glucose.

关键词： albendazole oxfendazole Cysticerci cellulosae target energy metabolism

Rapid determination of C1^- by light-absorption ratio variation approach using Cl^--eosin Y-Ag^+ adsorptive precipitation

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Chinese Chemical Letters 2008年第5期19卷 569-572页

作者： Jing Bai hong yan Wang hong Wen gao State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and Engineering Tongji University Shanghai 200092 China

The adsorptive precipitation between eosin Y （EY） and AgCl colloids at pH 3.73 caused the sensitive color change of the solution. The reaction mechanism between EY and AgCl was analyzed and this reaction was used fo... 详细信息

关键词： Determination of chloride Eosin Y Adsorptive precipitation Light-absorption ratio variation approach

Tomato Fruit Development and Ripening Are Altered by the Silencing of LeEIN2 Gene

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Journal of Integrative Plant Biology 2006年第12期48卷 1478-1485页

作者： hong-Liang Zhu Ben-Zhong Zhu Yi Shao Xiao-Guang Wang Xi-Jin Lin Yuan-hong Xie Ying-Cong Li hong-yan gao Yun-Bo Luo Laboratory of Fruit Biology College of Food Science and Nutritional Engineering China Agricultural University Beijing 100083 China

Loss-of-function ethylene insensitive 2 （EIN2） mutations showed ethylene insensitivity in Arabidopsis, which indicated an essential role of EIN2 in ethylene signaling. However, the function of EIN2 in fruit ripening has not been investigated. To gain a better understanding of EIN2, the temporal regulation of LeEIN2 expres- sion during tomato fruit development was analyzed. The expression of LeEIN2 was constant at different stages of fruit development, and was not regulated by ethylene. Moreover, LeEIN2-silenced tomato fruits were developed using a virus-induced gene silencing fruit system to study the role of LeEIN2 in tomato fruit ripening. Silenced fruits had a delay in fruit development and ripening, related to greatly descended expression of ethylene-related and ripening-related genes in comparison with those of control fruits. These results suggested LeEIN2 positively mediated ethylene signals during tomato development. In addition, there were fewer seeds and Iocules in the silenced fruit than those in the control fruit, like the phenotype of parthenocarpic tomato fruit. The content of auxin and the expression of auxin-regulated gene were declined in silenced fruit, which indicated that EIN2 might be important for crosstalk between ethylene and auxin hormones.

关键词： ethylene fruit development LeEIL1 LeEIN2 tomato virus-induced gene silencing

Thermal and mechanical behavior of casting copper alloy wheel during wheel and belt continuous casting process

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China Foundry 2024年第1期21卷 82-90页

作者： Kun gao yan Peng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

To investigate the thermal and mechanical behavior of casting wheel,a two-dimensional thermoelastic-plastic finite element model was used to predict the temperature,stress and distortion distribution of the casting wheel during the wheel and belt continuous casting *** effects of grinding thickness and casting speed on the thermal and mechanical behaviors of the center of the hot face of the casting wheel were discussed in *** each rotation,the casting wheel passes through four different spray *** results show that the temperature distribution of the casting wheel in different spray zones is similar,the temperature of the hot face is the highest and the temperature reaches the peak in the spray zoneⅢ.The stress and distortion depend on the temperature distribution,and the maximum stress and distortion of the hot face are 358.2 MPa and 1.82 mm,*** temperature at the center of the hot face decreases with increasing grinding thickness and increases with increasing casting speed.

关键词： casting wheel finite element model grinding thickness casting speed hot face spray zones

Numerical simulation of fluid flow and free surface fluctuations during wheel and belt casting process

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Journal of Iron and Steel Research International 2024年第5期31卷 1117-1126页

作者： Kun gao yan Peng National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina

The unstable fluid flow and severe free surface fluctuations in the wheel and belt caster can affect the quality of the cast *** lower level height tends to entrap inclusions in the molten *** the other hand,the higher level height makes the production process more dangerous due to the overflow of high temperature fluid from the mold.A computational model of the molten metal pouring process was *** transient fluid flow and free surface fluctuations behavior were calculated using the three-dimensional large eddy simulation model and the volume of fluid *** results show that the flow velocity of the main jet gradually decreases under the influence of the low kinetic energy fluid in the *** is an obvious oscillation in the tail of the jet,while the flow field is asymmetric in *** jet is closer to the inside radius side due to the Coanda effect,and there is a recirculation zone on the inside radius and the outside radius respectively,according to the 10 s time-averaged *** with the industrial observation and simulation results,the shape of the free surface is a wave that varies with *** addition,the free surface height is lowest and the flow velocity is highest in the region near the jet.

关键词： Fluid flow Free surface Wheel and belt caster Large eddy simulation Volume of fluid method

Significantly Enhanced Melt Memory Effect of Metallocene-made Isotactic Polypropylene Containing Talc

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Chinese Journal of Polymer Science 2024年第2期42卷 213-222,I0008页

作者： hong-Wen Sun Fu-Shan Wang yan gao Fu-Qing Wei Jia-Chun Feng State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China Lanzhou Petrochemical Corporation of PetroChina Lanzhou730060China Lanzhou Petrochemical Research Center Petrochemical Research Institute of PetroChinaLanzhou730060China

The melt memory effect is a widely observed phenomenon in semi-crystalline polymers. In practical applications, various additives are usually introduced into polymers, which may affect their melt memory behavior. In this work, the effect of talc on the melt memory effect of metallocene-made isotactic polypropylene(M-PP) was investigated in detail by using the differential scanning calorimetry. The results indicated that the introduction of talc significantly strengthened the melt memory effect of M-PP. Specifically, the upper limit temperature of Domain II increased from 161 ℃ to 174 ℃, resulting in a substantial widening of the temperature range of Domain IIa from 1 ℃ to 14 ℃. Analysis of the crystal orientation of the M-PP containing talc cooled from various Ts suggested that the remarkably enhanced melt memory effect could be ascribed to the stabilization of oriented nuclei facilitated by talc. This stabilizing effect was likely attributable to the prefreezing effect or the sorption interaction between talc and the M-PP chains.

关键词： Metallocene-made isotactic polypropylene Talc Melt memory effect Crystal orientation