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Chinese Chemical Letters 2012年第10期23卷 1141-1144页

作者： Yong Ling you An Xiao guang Tong Chen Dong Geng Wang Yu qin Li Xin Yang Wang Heng Zheng Department of Pharmacy School of MedicalNantong UniversityNantong 226001China Medicinal College Anhui College of Traditional Chinese MedicineHefei 230031China Department of Bioinformatics College of Life Science and TechnologyChina Pharmaceutical UniversityNanjing 210009China

Novel farnesylthiosalicylic acid （PTA） derivatives 5a-m with different substituted 1,3,4-thiadiazoles were synthesized. Compounds 5b, 5e, 5e and 5f displayed anti-tumor activities superior to FTA in most cancer cells tested. Furthermore, 5e induced tumor cell apoptosis, which was accompanied by lower Bcl-2 expression, but with higher Bax and caspase 3 expression activities in cancer cells.

关键词： Synthesis Farnesylthiosalicylic acid 1,3,4-Thiodiazole Anti-tumor agents Cytotoxic activities Cell apoptosis

Design and Application of a DSP Controller for Giant Magnetostrictive Smart Structure

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Chinese Journal of Aeronautics 2006年第B12期19卷 220-223页

作者： ZHANG Wen-guang Mao Jian-qin School of Mechanical Engineering and Automation Beijing University of Aeronautics and Astronautics Beijing 100083 China

It is proposed a digital signal processing （DSP） controller used in the control system of six degree-of-freedom （DOF） giant magnetostrictive smart structure （GMSS）. Also are presented the controller design and its implementation, the embedded adaptive least mean-square （LMS） control algorithm and the real-time experiments of GMSS. Three programs are embedded in this controller. Of them are the adaptive LMS control algorithm and the other two which are used to search for the optimal values for the initial weight vectors. Moreover, the work flow and the control approach of the GMSS with the DSP controller are introduced. The experimental results indicate that the DSP controller has better control precision and real-time property, and the damping effect is up to 20 dB-30 dB.

关键词： GMSS DSP active vibration control LMS algorithm

An Attribute-Based Access Control with Efficient and Secure Attribute Revocation for Cloud Data Sharing Service

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Journal of Electronic Science and Technology 2017年第1期15卷 90-98页

作者： Nyamsuren Vaanchig Wei Chen Zhi-guang qin School of Information and Software Engineering Universityof Electronic Science and Technology of ChinaChengdu 610054China

Nowadays, there is the tendency to outsource data to cloud storage servers for data sharing purposes. In fact, this makes access control for the outsourced data a challenging issue. Ciphertext-policy attribute-based encryption（CP-ABE） is a promising cryptographic solution for this challenge. It gives the data owner（DO） direct control on access policy and enforces the access policy cryptographically. However,the practical application of CP-ABE in the data sharing service also has its own inherent challenge with regard to attribute revocation. To address this challenge, we proposed an attribute-revocable CP-ABE scheme by taking advantages of the over-encryption mechanism and CP-ABE scheme and by considering the semitrusted cloud service provider（CSP） that participates in decryption processes to issue decryption tokens for authorized users. We further presented the security and performance analysis in order to assess the effectiveness of the scheme. As compared with the existing attributerevocable CP-ABE schemes, our attribute-revocable scheme is reasonably efficient and more secure to enable attribute-based access control over the outsourced data in the cloud data sharing service.

关键词： attribute cloud challenging encryption token challenge enable secret reasonably inherent

Studies on Synthesis and Properties of Mg-Al-nitrate Layered Double Hydroxides

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Chinese Chemical Letters 2003年第1期14卷 79-82页

作者： qin Zheng YANG Chun guang ZHANG 等 KeyLaboratoryforColloid&InterfaceChemistryofEducationMinistry ShandongUniversityJinan250100 KeyLaboratoryforColloid&InterfaceChemistryofEducationMinistry ShandongUniversityJina

A positive Mg-Al-nitrate layered double hydroxides (LDHs) has been synthesized using a non-steady coprecipitation method. The shape, size, chemical composition, electrical property and anion exchange property of the positive nanoparticle were studied by SEM, XRD, FTIR, chemical analysis, spectroanalysis and measuring of electrophoretic mobilities. Preliminary results show the positive nanoparticle is a promising precursor of polymer/LDHs nanocomposite.

关键词： Layered double hydroxide nanoparticle synthesis positive.

Pullback Attractors for a 3D Non-autonomous Navier-Stokes-Voight Equations

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Acta Mathematicae Applicatae Sinica 2019年第4期35卷 737-752页

作者： Yu-ming qin Xin-guang YANG Xin LIU Department of Applied Mathematics Donghua University Shanghai 201620 China Department of Mathematics and Information Science Henan Normal University Xinxiang 453007 China School of Information Science and Technology Donghua University Shanghai 201620 China Department of Applied Mathematics School of Statistics and Information Shanghai University of International Business and Economics Shanghai 201620 China

This paper is concerned with the existence of pullback attractors for the three dimensional nonautonomous Navier-Stokes-Voight equations for the processes generated by the weak and strong solutions. The main difficulty is how to establish the pullback asymptotic compactness via energy equation approach under suitable assumption on external force.

关键词： Navier-Stokes-Voight equations processes pullback attractor

Wind-tunnel experimental studies of the spatial snow distribution over grass and bush surfaces

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Journal of Hydrodynamics 2022年第1期34卷 85-93页

作者： guang Li Jun-ming qin Hong-xiang Yu Ning Huang Key Laboratory of Mechanics on Disaster and Environment in Western China The Ministry of Education of ChinaLanzhou UniversityLanzhou730000China School of Civil Engineering and Mechanics Lanzhou UniversityLanzhou730000China College of Atmospheric Science Lanzhou UniversityLanzhou730000China School of Architecture Civil and Environmental EngineeringSwiss Federal Institute of Technology LausanneLausanneSwitzerland

The snow is one of the most important water resources in grassland in northern and western China, while the wind blowing snow due to the strong wind there is a common phenomenon, which can lead to heavy disasters to harm the local animal husbandry and transportation. A reasonable arrangement of the snow protection forests is one of the most economical and effective methods to prevent the wind blowing snow, and a great number of investigations were carried out for its wind block effects. However, the deposition patterns of the snowfall and the blowing snow in the forests are still largely unknown. In this study, the wind tunnel experiments are performed to investigate the influences of the vegetation (grass and bush) on the wind speed profiles and the spatial distribution of the accumulated snow, by using the bran as the snow substitute. The snow blocking abilities of two bush models are analyzed to show the effects of different coverages. The results show that the grass and the bush have different effects on the wind speed profiles, and the snow-blocking abilities of the vegetation and the resulting spatial distribution are determined by the amount of the snowfall, the wind speed, and the height and the coverage of the vegetation. For the engineering design, if the snow is required on the windward side of the vegetation or in the vegetation, the densely arranged forest belts are needed, if the snow is required to accumulate on the leeward side of the vegetation, the sparse forest belts can be used. This work would be helpful as a reference to the reasonable arrangement of the snow-protection forests in pastoral areas.

关键词： Wind tunnel experiment wind speed profile vegetation snow-protection forest snow blocking ability

Experimental investigation of unsteady attached cavitating flow induced pressure fluctuation

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Journal of Hydrodynamics 2022年第1期34卷 31-42页

作者： Hou-sheng Zhang guang-hao Chen qin Wu Biao Huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China AVIC Jincheng Nanjing Engineering Institute of Aircraft System Nanjing211106China

This paper experimentally investigates the pressure fluctuation induced by the unsteady attached cavitating flow, with special focus on the quasi-periodic cloud cavitation. A simultaneous sampling method is adopted for the synchronous measurement of the wall pressure signals and the cavitating flow images in a convergent-divergent channel. The results show that the pressure fluctuation is composed of three parts, the flow noise, the low-frequency fluctuation, and the cavity collapse induced impulse, and the pressure evolution of the quasi-periodic cloud cavitation is well consistent with the cavitation evolution. The statistical analysis of the pressure fluctuation shows that, when σ > 1.01, the probability density function (PDF) is nearly in the normal distribution, implying the randomness of the pressure fluctuation, when 0.84 1.01, when σ < 0.84, the PDF becomes narrow and asymmetric. In addition, the variance and the average value of the pressure indicate that the fluctuation intensity increases downstream along the cavity and reaches the maximum at the cavity closure and it also increases with the decrease of the cavitation number. The spectral analysis shows that the low-frequency pressure fluctuations mainly consist of two dominant components, the cavity shedding induced fluctuation and the lock-in fluctuation. The cavity shedding induced frequency decreases with the decrease of the cavitation number but the lock-in frequency is kept nearly constant. According to the spectral analysis of the cavity area fluctuation and the modal analysis of the flow system, the lock-in is possibly caused when the fluctuation frequency of the cavity volume approaches the natural frequency of the flow system.

关键词： Cavitation pressure fluctuation statistical features lock-in phenomenon

Recovery of valuable metals from waste diamond cutters through ammonia–ammonium sulfate leaching

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International Journal of Minerals,Metallurgy and Materials 2017年第12期24卷 1352-1360页

作者： Ping Xue guang-qiang Li Yong-xiang Yang qin-wei qin Ming-xing Wei Key Laboratory for Ferrous Metallurgy and Resource Utilization of Ministry of Education Wuhan University of Science and Technology School of Electromechanical and Architectural Engineering Jianghan University Department of Materials Science and Engineering Delft University of Technology

Copper and zinc were recovered from waste diamond cutters through leaching with an ammonia–ammonium sulfate system and air as an oxidant. The effects of experimental parameters on the leaching process were investigated, and the potential–pH(E–pH) diagrams of Cu–NH_3–SO_4^(2-)–H_2O and Zn–NH_3–SO_4^(-2)–H_2O at 25°C were drawn. Results showed that the optimal parameters for the leaching reaction are as follows: reaction temperature, 45°C; leaching duration, 3 h; liquid-to-solid ratio, 50:1(mL/g); stirring speed, 200 r/min; ammonia concentration, 4.0 mol/L; ammonium sulfate concentration, 1.0 mol/L; and air flow rate, 0.2 L/min. The results of the kinetics study indicated that the leaching is controlled by the surface chemical reaction at temperatures below 35°C, and the leaching is controlled by diffusion through the product layer at temperatures above 35°C.

关键词： recovery waste diamond cutters renewable resources ammonia–ammonium sulfate leaching kinetics

The role of periphytes in the shift between macrophyte and phytoplankton dominated systems in a shallow,eutrophic lake (Lake Taihu,China)

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Science China(Life Sciences) 2006年第6期49卷 597-602页

作者： qin Boqiang SONG Yuzhi GAO guang Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China

Based on experiments of periphyte response to different trophic levels and their impact on macrophyte production,it was found that the periphyte biomass increased with the nutrient con-centrations. Increased trophic level and periphyte biomass resulted in decreased macrophyte photo-synthesis. It was suggested that the periphytes could cause resilience and hysteresis in the system shifts between macrophyte and phytoplankton domination. Other factors,such as fish farming,storm induced waves and mechanical destruction,and high water levels could be the perturbations during the system shifts,but these are not the key factors. Instead,the nutrient loading and periphyte abundance could determine the shift in lake ecosystem between macrophyte and phytoplankton domination. This finding could theoretically elucidate the mechanism of ecosystem shifts between macrophyte and phytoplankton domination.

关键词： shallow lake, eutrophication, ecosystem shift, macrophyte, phytoplankton.

Inhibited experimental corneal neovascularization by neutralizing anti-SDF-1α antibody

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International Journal of Ophthalmology(English edition) 2012年第1期5卷 7-12页

作者： Gao-qin Liu, Xue-guang Zhang Department of Ophthalmology the First Affiliated Hospital of Soochow University Suzhou 215006 Jiangsu Province China Jiangsu Institute of Clinic Immunology the First Affiliated Hospital of Soochow University Suzhou 215006 Jiangsu Province China

AIM: To explore the effect of SDF-1α on the development of experimental corneal neovascularization (CRNV).METHODS: CRNV was induced by alkali injury in mice. The expression of SDF-1α and CXCR4 in burned corneas was examined by Flow Cytometry. Neutralizing anti-mouse SDF-1α antibody was locally administrated after alkali injury and the formation of CRNV 2 weeks after injury was assessed by Immunohistochemistry. The expression of VEGF and C-Kit in burned corneas was detected by ***: The number of CRNV peaks at 2 weeks after alkali injury. Compared to control group, SDF-1α neutralizing antibody treatment significantly decreased the number of CRNV. RT-PCR confirmed that SDF-1α neutralizing antibody treatment resulted in decreased intracorneal VEGF and C-Kit ***: SDF-1α neutralizing antibody treated mice exhibited impaired experimental CRNV through down regulated VEGF and C-Kit expression.

关键词： corneal neovascularization alkali injury chemokine