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Controlled Ring-opening(Co)Polymerization of Renewable Macrolactones by Al-based Catalysts with Different Sidearms

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Chinese Journal of Polymer Science 2023年第11期41卷 1706-1713,I0006页

作者： wu-Chao Zhao Jing Yuan Jiang-hua He yue-Tao Zhang State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China

It remains a challenging task to achieve ring-opening(co)polymerization(ROP)of ***,we synthesized a series of Al-based catalysts and systemically investigated the effect of N-containing substituent on the sidearms on ROP of ***3 possessing Nmethyl group could effectively achieve controlled ROP of pentadecalactone(PDL)and macro(di)lactone ethylene brassylate(EB)in combination with BnOH,furnishing polyethylene-like PPDL and PEB with M_(W)up to 90.3 and 321 kg/mol,*** copolymerization of PDL and small-ring lactonesε-caprolactone(e-CL)andδ-valerolactone(δ-VL)could prepare random copolyesters with tailored T_(m)in the range of 57-94℃by controlling the ratios of PDL and e-CL,*** importantly,well-defined block copolyesters could be obtained by sequential adding PDL andε-CL,δ-VL,which have been proved by GPC-MALLS,DSC and^(13)C-NMR.

关键词： Ring-opening(co)polymerization Macrolactones Polyethylene-like polymers Sidearm effect Aluminum complex

Microencapsulation of Fish Oil by Simple Coacervation of Hydroxypropyl Methylcellulose

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Chinese Journal of Chemistry 2005年第11期23卷 1569-1572页

作者： wu, Ke-Gang CHAI, Xiang-hua CHEN, yue Food Science and Bioengineering Department Guangdong University of Technology Guangzhou Guangdong 510090 China Biology Department Shantou University Shantou Guangdong 515063 China

To improve the oxidative stability and application of fish oil, it was microencapsulated by simple coacervation followed by spray drying. Simple coacervation took place by adding malt dextrin into the emulsion of fish oil and hydroxypropyl methylcellulose （HPMC） solution. Influences of several process parameters on the microencapsulation were evaluated and the oxidative stability and microstructure of microcapsules were analyzed. Results showed that the coacervation could be observed only when dextrose equivalent value （DE value） of malt dextrin, concentration of HPMC solution and fish oil percentage in microcapsules were no more than 20. 5% and 40%, respectively. Moreover, microencapsulation efficiency was higher at HPMC solution concentration of 4% and fish oil percentage of less than 30%. The oxidative stability of fish oil was improved by the microencapsulation and done best in the ease of replacing malt dextrin by 40% with acacia. Scanning electronic microscopic photographs showed that the microcapsule obtained was a round, smooth and hollow microcapsule with its wall made up of innumerable small and solid submicrocapsules with the core of fish oil.

关键词： fish oil hydroxypropyl methylcellulose malt dextrin microencapsulafion simple coacervation

Application of PCR-DGGE in Research of Bacterial Diversity in Drinking Water

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Biomedical and Environmental Sciences 2006年第5期19卷 371-374页

作者： QING wu XIN-hua ZHAO SHENG-yue ZHAO Department of Environmental Science and Engineering Tianjin University Tianjin 300072 China

Objective To analyze the structure of bacteria in drinking water by molecular biological techniques, Methods DNA of bacteria in drinking water was directly extracted without culture. 16S ribosomal DNA fragments, including V-6, -7, and -8 regions, were amplified with universal primers （EUBf933CJC and EUBr1387） and analyzed by DGGE. Results DGGE indicated that amplification products could be separated, The results showed that DGGE could be used in the separation of different microbial 16SrRNA genes extracted from drinkng water. Though there were special bacteria in different water samples, the predominant bacteria were essentially the same. Three sequences of the reclaimed specific bands were obtained, and phylogenetic tree of these bands was made. Conclusion Bacterial diversity in drinking water is identified by molecular biological techniques.

关键词： Drinking water Denaturing gradient gel electrophoresis (DGGE) 16S ribosome RNA Microbial diversity

Fabrication and Performance of a Low Operating Pressure Nanofiltration Poly(vinyl chloride) Hollow Fiber Membrane

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Chinese Journal of Polymer Science 2014年第3期32卷 377-384页

作者： Jian-hua Wang yue-li wu Yong-hua Zhang 朱宝库 You-yi Xu MOE Key Laboratory of Macromolecular Synthesis and Functionalization MOE Engineering Research Center of Membrane and Water Treatment TechnologyDepartment of Polymer Science and EngineeringZhejiang University

A low operating pressure nanofiltration membrane is prepared by interfacial polymerization between m-phenylenediamine （MPDA） and trimesoyl chloride （TMC） using PVC hollow fiber membrane as supporting. A series of PVC nanofiltration membranes with different molecular weight cutoff （MWCO） can be obtained by controlling preparation conditions. Chemical and morphological characterization of the membrane surface was carried out by FTIR-ATR and SEM. MWCO was characterized by filtration experiments. The preparation conditions were investigated in detail. At the optimized conditions （40 min air-dried time, aqueous phase containing 0.5% MPDA, 0.05% SDS and 0.6% acid absorbent, oil phase containing 0.3% TMC, and 1 min reaction time）, under 0.3 MPa, water flux of the gained nanofiltration membrane reaches 17.8 L/m2-h, and the rejection rates of methyl orange and MgSO4 are more than 90% and 60%, respectively.

关键词： PVC Interracial polymerization Nanofiltration membrane Hollow fiber membrane.

Suadimins D—J,Monoterpenoid Indole-Quinoline and Bisindole Alkaloids from Melodinus suaveolens

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Chinese Journal of Chemistry 2023年第18期41卷 2296-2304页

作者： Xin-hua Gao Pei-Qian wu Yao-yue Fan Bin Zhou Jian-Min yue State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of Sciences555 Zuchongzhi RoadShanghai201203China shandong Laboratory of Yantai Drug Discovery Bohai Rim Advanced Research Institute for Drug DiscoveryYantaiShandong 264117China Research Units of Discovery of New Drug Lead Molecules Chinese Academy of Medical SciencesShanghai 201203China

Comprehensive Summary,Compounds 1—12,including seven complex monoterpenoid indole-quinoline and bisindole alkaloids,suadimins D—J(1—7)with previously unreported carbon-carbon linkages,were isolated and identified from the twigs and leaves of Melodinus *** structures were elucidated by a combination of diverse methods,especially the extensive spectroscopic data analysis and electric circular dichroism(ECD)*** cytotoxicity of these compounds against three cancer cell lines was evaluated,some of which showed moderate activities with IC50 values ranging from 2.4 to 8.0μM.

关键词： Melodinus suaveolens Alkaloids Dimerization Structure elucidation ECD calculations Cytotoxic activity

Use of high-resolution X-ray computed tomography and 3D image analysis to quantify mineral dissemination and pore space in oxide copper ore particles

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International Journal of Minerals,Metallurgy and Materials 2017年第9期24卷 965-973页

作者： Bao-hua Yang Ai-xiang wu Guillermo A.Narsilio Xiu-xiu Miao Shu-yue wu Information Science and Engineering School Hunan International Economics UniversityChangsha 410205China Department of Infrastructure Engineering The University of MelbourneVictoria 3010Australia Key Laboratory of High-efficient Mining and Safety of Metal Mines(Ministry of Education) University of Science and Technology BeijingBeijing 100083China

Mineral dissemination and pore space distribution in ore particles are important features that influence heap leaching performance. To quantify the mineral dissemination and pore space distribution of an ore particle, a cylindrical copper oxide ore sample (I center dot 4.6 mm x 5.6 mm) was scanned using high-resolution X-ray computed tomography (HRXCT), a nondestructive imaging technology, at a spatial resolution of 4.85 mu m. Combined with three-dimensional (3D) image analysis techniques, the main mineral phases and pore space were segmented and the volume fraction of each phase was calculated. In addition, the mass fraction of each mineral phase was estimated and the result was validated with that obtained using traditional techniques. Furthermore, the pore phase features, including the pore size distribution, pore surface area, pore fractal dimension, pore centerline, and the pore connectivity, were investigated quantitatively. The pore space analysis results indicate that the pore size distribution closely fits a log-normal distribution and that the pore space morphology is complicated, with a large surface area and low connectivity. This study demonstrates that the combination of HRXCT and 3D image analysis is an effective tool for acquiring 3D mineralogical and pore structural data.

关键词： high-resolution X-ray computed tomography 3D image analysis ore particles mineral dissemination pore space

Apollo: Rapidly Picking the Optimal Cloud Configurations for Big Data Analytics Using a Data-Driven Approach

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Journal of Computer Science & Technology 2021年第5期36卷 1184-1199页

作者： yue-Wen wu Yuan-Jia Xu Heng wu Lin-Gang Su Wen-Bo Zhang hua Zhong University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Computer Science Institute of SoftwareChinese Academy of SciencesBeijing 100190China

Big data analytics applications are increasingly deployed on cloud computing infrastructures,and it is still a big challenge to pick the optimal cloud configurations in a cost-effective *** this paper,we address this problem with a high accuracy and a low *** propose Apollo,a data-driven approach that can rapidly pick the optimal cloud configurations by reusing data from similar *** first classify 12 typical workloads in BigDataBench by characterizing pairwise correlations in our offline *** a new workload comes,we run it with several small datasets to rank its key characteristics and get its similar *** on the rank,we then limit the search space of cloud configurations through a classification *** last,we leverage a hierarchical regression model to measure which cluster is more suitable and use a local search strategy to pick the optimal cloud configurations in a few extra *** evaluation on 12 typical workloads in HiBench shows that compared with state-of-the-art approaches,Apollo can improve up to 30%search accuracy,while reducing as much as 50%overhead for picking the optimal cloud configurations.

关键词： big data analytics cloud configuration data driven

Molecular Dynamics Simulation of Microstructure of Nanocrystalline Copper

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Chinese Physics Letters 2001年第3期18卷 411-413页

作者： WEN Yu-hua ZHOU Fu-Xin LIU yue-wu State Key LNM Institute of MechanicsChinese Academy of SciencesBeijing 100080

The microstructure of computer generated nanocrystalline coppers is simulated by using molecular dynamics with Finnis-Sinclair potential,analysed by means of radial distribution functions,coordination number,atomic energy and local crystalline *** influence of the grain size on the nanocrystalline structure is *** results reveal that as the grain size is reduced,the grain boundary shows no significant structural difference,but the grain interior becomes more disordered,and their structural difference diminishes gradually;however,the density and the atomic average energy of the grain boundary present different tendencies from those of the grain interior.

关键词： grain Microstructure microstructure

Comparative study on identi¯cation of healthy and osteoarthritic articular cartilages by fourier transform infrared imaging and chemometrics methods

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Journal of Innovative Optical Health Sciences 2017年第3期10卷 43-51页

作者： Zhi-hua Mao yue-Chao wu Xue-Xi Zhang Hao Gao Jian-hua Yin Department of Biomedical Engineering Nanjing University of Aeronautics and Astronautics 29 Yudao St Nanjing210016 JiangsuP.R.China

Two discriminant methods,partial least squares-discriminant analysis(PLS-DA)and Fisher's discriminant analysis(FDA),were combined with Fourier transform infrared imaging(FTIRI)to differentiate healthy and osteoarthritic articular cartilage in a canine *** cartilage had been developed for up to two years after the anterior cruciate ligament(ACL)transection in one *** specimens were sectioned into 10μm thickness for FTIRI.A PLS-DA model was developed after spectral *** IR spectra extracted from FTIR images were calculated by PLS-DA with the discriminant accuracy of 90%.Prior to FDA,principal component analysis(PCA)was performed to decompose the IR spectral matrix into informative princi pal component *** on the different discriminant mechanism,the discriminant accuracy(96%)of PCA-FDA with high convenience was higher than that of *** healthy cartilage sample was mis assigned by these two *** above mentioned suggested that both integrated technologies of FTIRI-PLS-DA and,especially,FTIRI-PCA-FDA could become a promising tool for the discrimination of healthy and osteoarthritic cartilage specimen as well as the diagnosis of cartilage lesion at microscopic *** results of the study would be helpful for better understanding the pathology of osteoarthritics.

关键词： Articular cartilage osteoarthritis Fourier transform infrared imaging partial least squares discriminant analysis Fisher's discriminant analysis.