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Studies on the flame propagation characteristic and thermal hazard of the premixed N2O/fuel mixtures

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Defence Technology（防务技术） 2020年第3期16卷 564-570页

作者： Yu-yan Li Rong-pei Jiang Zhi-peng Li Sen Xu Feng Pan Li-feng Xie School of Chemical Engineering Nanjing University of Science and TechnologyNanjingJiangsu 210094PR China Beijing Insitute of Aerospace Testing Technology Beijing Key Laboratory of Research and Application for Aerospace Green PropellantsBeijing 100074PR China national quality Supervision and inspection center for Industrial Explosive Materials NanjingJiangsu 210094PR China

An experimental study was carried out to investigate the flame propagation and thermal hazard of the premixed N2O/fuel mixtures,including NH3,C3H8 and *** study provided the high speed video images and data about the flame locations,propagation patterns,overpressures and the quenching diameters during the course of combustion in different channels to elucidate the dynamics of various combustion *** onset decomposition temperature was determined using high-performance adiabatic *** was shown that the order of the flame acceleration rate and thermal hazard was N2O/C2H4>N2O/C3H8>N2O/NH3.

关键词： Flame propagation Flame acceleration rate Quenching diameter Thermal hazard

Isolation and phylogenetic study of Rift Valley fever virus from the first imported case to China

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Virologica Sinica 2017年第3期32卷 253-256页

作者： Yongxia Shi Kui Zheng Xiaobo Li Liqiang Li Shufen Li Jinmin Ma Jun Dai Jingkai Ji Shuai Yuan Haorong Lu Jiandong Li Fangfang Sun Xun Xu Jicheng Huang inspection and Quarantine Technology center Guangdong Entry-Exit Inspection and Quarantine Bureau BGI-Shenzhen China national Gene Bank-Shenzhen BGI-Shenzhen Department of Biology University of Copenhagen BGI Education center University of Chinese Academy of Sciences

Dear Editor,Rift Valley fever(RVF)is an anthropozoonosis caused by Rift Valley fever virus(RVFV).RVFV belongs to the Phlebovirus genus in the family Bunyaviridae,which is circulating among *** infection with RVFV is g... 详细信息

关键词：裂谷热病毒人畜共患传染病系统进口中国反刍动物人类感染并发症

Optimization of Detection Methods for Avermectin Residue

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Animal Husbandry and Feed Science 2012年第1期4卷 10-12,15页

作者： PAN Yuan NIU Hua ZHANG Xue-zhong REN Yi Yunnan Provincial Institute of Product quality Supervision and inspection Kunming 650223China national center for Tropical Agricultural Product quality Supervision&inspection Kunming 650223China

[ Objective] To develop an efficient and practical method for detecting avermectin residue in animal-derived food. [ Method ] Acetonitrile was used as the extraction fluid. After the removal of moisture, trifluoroacetic anhydride and N-methyl imidazole were used for derivatization and mixed well. After complete derivatization, high-performance liquid chromatography （HPLC） with C18 column was used for accurate qualitative and quantitative analysis of the detected substance using methanol aqueous solution （92： 8, V/ V）. [ Result] The detection limit of HPLC connected with a fluorescence detector was up to 0.1 ug/L. When the standard was added to the substrate at a final concentration in the range of 0.1 -20.0 lag/L, the recoveries were in the range of 80% -108% and the relative deviation was in the range of 4.1% -11.4%. [ Conclusion] The developed HPLC con- nected with a fluorescence detector is simple, practical, highly sensitive and resistant to interference, and it thus can meet the needs for determina- tion of biological toxin residues of avermectins in animal-derived food in laboratory.

关键词： Avermectin residues High-performance liquid chromatography Fluorescence detector

Design And Preparation Of Cement-based Composite with Electromagnetic Protection

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Design And Preparation Of Cement-based Composite with Electr...

The Application of the Steel Slag in the Radiation Shield Heavy Concrete

中国材料大会2012

作者： Kun Tian Shengyin Zhou Jiangrong Xiao Ruguang Li Peng Yao national Energy-Saving Construction Material quality Supervision inspection center

ISBN: (纸本)9783037856062;3037856068

Using space electromagnetic wave propagation principle, environment requirements of building protective engineering structure and performance characteristics of cement-based composites, a design idea of cement-based composite with electromagnetic protection is presented in the present study. This design idea was tested and verified. According to the proposed new designed method, by optimizing and selecting the wave-transparent aggregate and absorbing agent material, the absorbing composite materials of cement-based electromagnetic protection, electromagnetic wave absorbent, energy saving and environmental protection can be improved. A new cement-based composite with electromagnetic protection and microwave absorbing properties （the minimum reflectivity is -8.4dB）, wide frequency bandwidth, and letter mechanical properties was prepared by using a 20 mm sample between 8-18 GHz. The results provide a basis design and preparation of cement-based composite with electromagnetic protection.

关键词： Electromagnetic protection Cement-based Composite.

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The Application of the Steel Slag in the Radiation Shield He...

Effect of Methylene Blue (MB)-value of Manufactured Sand on the Durability of Concretes

中国材料大会2012

作者： Ruguang Li Shengyin Zhou Kun Tian Peng Yao national Energy-Saving Construction Material quality Supervision inspection center

ISBN: (纸本)9783037856062

The steel slag was broken into steel slag powders and sands. The performance of the radiation shield heavy concrete was studied in this work by mixing different content of steel slag sand and powder. The results showed that the water requirement of normal consistency and setting time increased with the increase of the content of the steel slag powder. The strength reduced in the early stage of the experiment. The strength increased firstly and decreased later. The optimal content of steel slag powder for strength was 20%. For the steel slag powder and sand, whether the concrete added one or two components, the concrete slump loss increased and strength reduced at 3 days. The steel slag powder and sand added into concrete improved the performance of the concrete effectively, solved the heavy aggregate subsidence and improved the concrete homogenous.

关键词： Steel slag powder Steel slag sand Working performance Homogeneous.

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Journal of Wuhan University of Technology(Materials Science) 2012年第6期27卷 1160-1164页

作者：王稷良 NIU Kaimin TIAN Bo SUN liqun Key Laboratory of Road Structure and Material Ministry of Communications(Beijing) Research Institute of Highway Ministry of CommunicationBeijing 100088China Guizhou Province Building Materials Product quality Supervision and inspection center Guiyang 550002China

The relation between the methylene blue （MB） value of MS and its limestone powder content and clay content was investigated. The effects of MB values ranging from 0.35 to 2.5 on the workability of fresh concrete, the mechanical properties, the resistance to freezing as well as the resistance to chlorine ion permeation of the hardened concrete were all investigated. The experimental results showed that the MB value had no correlation with the limestone powder content of MS, while it was directly related to the clay content. With an increase of MB value, concrete workability decreased, as did the flexural and 7-day compressive strengths, however, the 28-day compressive strength was not affected. Furthermore, influence of MB value on concretes of different strength levels was different. For low-strength concretes, an increase of MB value could improve its impermeability, but this was not the case for high-strength concretes. Instead, their resistance to chloride ion permeability decreased slightly. However, even a slight increase in MB value remarkably accelerated freeze-thaw damage of MS concrete. It was thus concluded that the critical MB value of 1.4 would not cause significant deterioration in the performance of MS concretes.

关键词： manufactured sand methylene blue value clay content resistance to freezing chlorine ionpermeability coefficient

Investigations for vibration and friction torque behaviors of thrust ball bearing with self-driven textured guiding surface

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Friction 2023年第6期11卷 894-910页

作者： Can WU Kai YANG Jing NI Shuigen LU Lidan YAO Xinglin LI School of Mechanical Engineering Hangzhou Dianzi UniversityHangzhou310018China Hangzhou Bearing Test&Research center with Assistance of UNDP/UNIDO Hangzhou310022China Machinery Industry Bearing quality inspection center(Hangzhou) Hangzhou310022China Sinopec Research Institute of Petroleum Processing Beijing100083China

In order to improve the starved lubrication condition of rolling bearings,three kinds of textures,namely dimple,groove texture,and gradient groove texture,were developed on the guiding surface of thrust ball bearings in this *** results show that gradient groove texture has the one-way self-driving function of liquid *** root mean square(RMS)value of vibration acceleration of gradient groove textured bearing(GGB)decreased by 49.1% and the kurtosis decreased by 24.6% compared with non-textured bearing(NB)due to the directional spreading effect of gradient groove textures on *** frequency domain analysis showed that the textures mainly suppressed the medium and high-frequency energy of bearing vibration,and the GGB was reduced the most with 65.3% and 48%,*** addition,whether the grease is sufficiently sheared has a large impact on the oil guiding effect,and the friction torque of GGB could decrease by 10.5% compared with NB in the sufficiently sheared ***,the gradient groove texture with oil self-driven effect on the guiding surface of rolling bearing can effectively improve the lubrication condition of the bearing and thus reduce the bearing vibration and friction torque,which has a promising application prospect.

关键词： self-driven textures gradient grooved bearing guiding surface bearing vibration friction torque

Ciprofloxacin stress changes key enzymes and intracellular metabolites of Lactobacillus plantarum DNZ-4

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Food Science and Human Wellness 2022年第2期11卷 332-340页

作者： Pin Chen Xiaoqian Chen Wei Yu Bo Zhou Lihua Liu Yuzhuo Yang Peng Du Libo Liu Chun Li Key Laboratory of Dairy Science Ministry of EducationFood Science CollegeNortheast Agricultural UniversityHarbin 150030China Institute of Animal Science(IAS) Chinese Academy of Agricultural Sciences(CAAS)Beijing 100193China national Dairy Product quality Supervision and inspection center Harbin 150024China

Ciprofloxacin(CIP)is an antibiotic used to treat infections caused by *** this experiment,key enzymes and intracellular metabolites of Lactobacillus plantarum DNZ-4 was researched under CIP *** results showed that the activities of hexokinase,pyruvate kinase,β-galactosidase and Na^(+),K^(+)-ATPase after 1/2 minimum bacteriostatic concentration(MIC)CIP treatment were significantly decreased(P<0.01).Gas chromatography-mass spectrometry was used to analysis the changes of main metabolites in the cells and principal component analysis and partial least square model were *** results indicated that CIP could cause changes in intracellular fatty acids,carbohydrates and amino acids,and the mechanism of amino acid metabolism under CIP stress was significantly *** DNZ-4 made stress response to CIP by regulating the ratio of saturated fatty acids and unsaturated *** experiment revealed the changes of growth and metabolism mechanism of *** DNZ-4 under CIP stress,which help to provide technical means for the development of effective probiotics preparation products.

关键词： Ciprofl oxacin Lactobacillus plantarum DNZ-4 Key enzymes Metabolism

Lactobacillus fermentum as a new inhibitor to control advanced glycation end-product formation during vinegar fermentation

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Food Science and Human Wellness 2022年第5期11卷 1409-1418页

作者： Qin Li Leibing Li Hanjian Zhu Fan Yang Ke Xiao Lin Zhang Menglin Zhang Yongsheng Peng Chao Wang Dongsheng Li Qian Wu Mengzhou Zhou Key Laboratory of Fermentation Engineering(Ministry of Education) National"111"Center for Cellular Regulation and Molecular PharmaceuticsHubei Key Laboratory of Industrial MicrobiologyCooperative Innovation Center of Industry Fermentation(Ministry of Education&Hubei Province)Hubei University of TechnologyWuhan 430068China Wuhan Product quality Supervision and inspection Institute Wuhan 430000China

The inhibitory activity of lactic acid bacteria(LAB)toward advanced glycation end-products(AGEs)during vinegar fermentation was studied,and its relationships with the substrate consumption,antioxidant capacity,total phenolic content,total flavonoid compounds,α-glucosidase,andα-amylase activity inhibition were *** vinegar was made from rice powder flour by liquid-state fermentation(LSF).The selected LAB strains were separately co-cultivated with Saccharomyces cerevisiae and Acetobacter pasteurianus 1.41 in alcoholic and acetic acid fermentation,*** 3 strains,Lactobacillus fermentum showed the strongest inhibitory effect on the formation of total fluorescent AGEs and carboxymethyl lysine(CML)/carboxyethyl lysine(CEL)in the fermentation *** corresponding mechanisms included the acceleration of substrate consumtion,improvement of antioxidant activities,and inhibition ofα-glucosidase andα-*** addition,the fluorescent AGEs and the CML/CEL were negatively correlated with the antioxidant activities,while theα-glucosidase andα-amylase activities were positively correlated with the total phenols and total ***,the variety of main flavor compounds increased,including esters,alcohols,phenols and *** results of the study support the potential use of screened LAB strains to inhibit the formation of fluorescent AGEs,CML and CEL on fermented products and in the food processing industry,without associated risks to consumers.

关键词： Lactobacillus fermentum Advanced glycation end-product Vinegar fermentation Antioxidant capacity