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Uncinatic acids A-C,three new carboxylated flavonoids from Selaginella uncinata

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Chinese Chemical Letters 2017年第7期28卷 1465-1468页

作者： rui liu Hui Zou Ping-Sheng Xu Zhen-Xing Zou Jing Li Fei Cheng rui-huan liu Gan Zhou Kang-Ping Xu Gui-Shan Tan Xiangya Hospital of Central South University Changsha 410008China Xiangya School of Pharmaceutical Sciences Central South UniversityChangsha 410013China

Three new carboxylated flavonoids, uncinatic acids A-C（1–3）, were isolated from the whole herb of Selaginella uncinata. Their structures were established on the basis of extensive NMR analysis including1 D, 2D NMR experiments and HR-ESIMS techniques. All of them share the carboxylation structural characteristic. Compounds 1 and 2 belong to novel naturally occuring furanoflavonoids which is firstly reported in genus Selaginella. Such furanoflavonoids with dicarboxylic acid structrure have never been discovered before. In addition, the isolates were tested for their cytotoxicity against A549 and BGC-823 cell lines in vitro.

关键词： Selaginella uncinata Selaginella Uncinatic acids A-C Carboxylated flavonoids Furanoflavonoids Anticancer Cytotoxicity

Fe/MCM-41 as a promising heterogeneous catalyst for ozonation of p-chlorobenzoic acid in aqueous solution

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Chinese Chemical Letters 2011年第6期22卷 683-686页

作者： rui huan huang Jie liu Lai Sheng Li Qiu Yun Zhang Li Xuan Zeng Ping Lu School of Chemistry & Environment South China Normal University Guangzhou 510006 China

Mesoporous MCM-41 and Fe loaded MCM-41（Fe/MCM-41）,which were successfully prepared by a hydrothermal method and a dipping method respectively,were applied as heterogeneous catalysts for ozonation of p-chlorobenzoic acid（p-CBA） in aqueous ***-41 and Fe/MCM-41 were characterized by XRD,FT-IR and diffuse reflectance UV-vis（DR-UV-vis） techniques. The presence of either MCM-41 or Fe/MCM-41 improves p-CBA and total organic carbon（TOC） removal efficiency compared to ozonation *** the experimental condition,TOC removal rate of Fe/MCM-41/O_3 process is over 63.5%at 60 min oxidation time,44.5%using MCM-41 as catalyst,only 37.7%with ozonation *** presence of tert-butanol（TBA） in the Fe/MCM-41/ O_3 process indicated that the oxidation mechanism of p-CBA occurs via OH in the liquid *** Fe/MCM-41 is a promising catalyst.

关键词： Fe/MCM-41 Catalytic ozonation p-Chlorobenzoic acid TOC

Characterization of the current crowding effect on chip surface using a quantum wide-field microscope

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Chinese Optics Letters 2024年第6期22卷 123-128页

作者： rui Zhao Ding Wang huan Fei Wen Yunbo Shi Jun Tang Jun liu Science and Technology on Electronic Test&Measurement Laboratory North University of ChinaTaiyuan 030051China

We characterize the current crowding effect for microwave radiation on a chip surface based on a quantum wide-field microscope combining a wide-field reconstruction technique. A swept microwave signal with the power of 0–30 d Bm is supplied to a dumbbell-shaped microstrip antenna, and the significant differences in microwave magnetic-field amplitudes attributed to the current crowding effect are experimentally observed in a 2.20 mm ×1.22 mm imaging area. The normalized microwave magnetic-field amplitude along the horizontal geometrical center of the image area further demonstrates the feasibility of the characterization of the current crowding effect. The experiments indicate the proposal can be qualified for the characterization of the anomalous area of the radio-frequency chip surface.

关键词： current crowding effect microwave field on chip surface quantum wide-field microscope nitrogen-vacancy center

A new abdominal drainage tube fixation method for 3-port laparoscopic cholecystectomy improves patients’postoperative quality of life

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Laparoscopic, Endoscopic and Robotic Surgery 2024年第3期7卷 107-112页

作者： Fenghua Zhang Lin Lin huan Zhang Jinghua liu rui Wang Department of Operating Room Linyi People’s HospitalLinyi 276000China Department of Health Care Linyi People’s HospitalLinyi 276000China Department of Hepatobiliary Surgery Guangzhou University of Chinese MedicineGuangzhou 510006China Department of Hepatobiliary Surgery and Minimally Invasive Institute of Digestive Surgery Linyi People’s HospitalLinyi 276000China

Objective Laparoscopic surgery has become a routine general surgery with many advantages,such as alleviating abdominal ***,postoperative pain caused by abdominal drainage tubes has attracted little attention from medical *** aim of this study was to explore the influence of a new abdominal drainage tube fixation method for 3-port laparoscopic cholecystectomy(LC)on patients’postoperative quality of *** Patients who underwent 3-port LC with abdominal drainage tubes in the Department of Hepatobiliary Surgery of Linyi People’s Hospital from March 1,2023 to October 31,2023 due to gallstones with chronic cholecystitis were selected for this *** patients were randomly divided into an experimental group and a control *** the experimental group,the new abdominal drainage tube fixation method was used,while in the control group,the traditional method was ***,the quality of life of patient in terms of pain,activity,recovery time,and mental health status was *** exudate around the patient’s drainage tube was collected for bacterial culture and *** A total of 139 patients were randomly divided into an experimental group(70 patients)and a control group(69 patients).The patients’baseline characteristics were not significantly *** patients in the experimental group had better outcomes in quality of life,with higher pain scores(24.03±2.37 vs.15.48±2.29,p<0.001)and activity scores(20.57±1.78 vs.14.13±1.43,p<0.001),and a shorter postoperative recovery time(2.36±0.68 d vs.2.96±1.34 d,p<0.001).The same results were shown in linear regression analysis scores of the 2 *** positive rate of bacterial culture in the exudate around the patient’s drainage tube in the experimental group was significantly lower than that in the control group(12.9%vs.43.5%,p<0.001);and furthermore,the positive rate of conditional pathogenic bacteria was even lower(7.1%vs.33.3%,p<0.001)in the experimental group than in the contro

关键词： Abdominal drainage tube Surgical site infection Quality of life Fixation method Laparoscopic cholecystectomy

Construction of multifunctional lanthanum manganese mixed nanoparticles mediated by ionic liquids for selective aerobic oxidation of cyclohexane

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Rare Metals 2024年第5期43卷 2205-2221页

作者： Hao Li rui-rui Zhang Ke-Xin Li Shuang Wei Yu-Mei liu rui-Xia liu Beijing Key Laboratory of Ionic Liquids Clean Process CAS Key Laboratory of Green Process and EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Selective oxidation of alkanes to produce highvalue chemicals is an essential strategy and means to realize efficient utilization of *** this work,a strategy of lanthanum manganese mixed metal oxides(LMMO)regulated via a facile ionic liquid(IL)-assisted hydrothermal method was proposed to construct the multifunctional catalysts,which exhibited excellent catalytic performance in the selective aerobic oxidation of *** 8.9%cyclohexane conversion with 90%KA oi(cyclohexanol and cyclohexanone)selectivity was achieved over the optimal LMMO catalyst under mild *** effects of anion type,carbon chain length and concentration of ILs on the structure and properties of catalysts were investigated through various characterizations,indicating the structure-directing and template effect of ILs on the multifunctional *** formation of self-assembled spherical nanoparticles followed the"dissolution-nucleation-proliferation"mechanism with the introduction of 1-butyl-3-methylimidazolium hydrogen sulfate,ascribing the synergistic effect between the microenvironment of ILs and the hydrothermal ***,the high reactive oxygen concentration redox capacity,and suitable basic sites of LMMO catalysts mediated by ILs enhance the activation of C-H bonds and molecular oxygen,simultaneously influencing the adsorption and desorption of the substrate.A comprehensive understanding of the high KA oil selectivity and radical reaction mechanism was elucidated based on in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and radical trapping *** recycling and regeneration experiments further illuminated that the removal of adsorbed cyclohexanone acting on the LMMO catalyst was the key to achieve high KA oil selectivity.

关键词： Ionic liquids Nanoparticle Multifunctional catalyst Cyclohexane oxidation

Non-Convex Optimization of Resource Allocation in Fog Computing Using Successive Approximation

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Journal of Systems Science & Complexity 2024年第2期37卷 805-840页

作者： LI Shiyong liu huan LI Wenzhe SUN Wei School of Economics and Management Yanshan UniversityQinhuangdao 066000China

Fog computing can deliver low delay and advanced IT services to end users with substantially reduced energy ***,with soaring demands for resource service and the limited capability of fog nodes,how to allocate and manage fog computing resources properly and stably has become the ***,the paper investigates the utility optimization-based resource allocation problem between fog nodes and end users in fog *** authors first introduce four types of utility functions due to the diverse tasks executed by end users and build the resource allocation model aiming at utility ***,for only the elastic tasks,the convex optimization method is applied to obtain the optimal results;for the elastic and inelastic tasks,with the assistance of Jensen’s inequality,the primal non-convex model is approximated to a sequence of equivalent convex optimization problems using successive approximation ***,a two-layer algorithm is proposed that globally converges to an optimal solution of the original ***,numerical simulation results demonstrate its superior performance and *** with other works,the authors emphasize the analysis for non-convex optimization problems and the diversity of tasks in fog computing resource allocation.

关键词： Fog computing non-convex optimization optimal resource allocation successive approximation method utility function

Strong and tough chitin hydrogel constructed by dehydration and rehydration strategy

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Nano Research 2024年第9期17卷 8192-8199页

作者： rui-rui liu Li-Bo Mao Shu-Hong Yu Division of Nanomaterials and Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials and ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China Institute of Innovative Materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

As a renewable,biocompatible,biodegradable soft material,chitin hydrogels have better advantages in stability,antibacterial activity,antifouling,cost,immunogenicity,and so on than most polymer ***,compared with other widely used polymer hydrogels with high strength and toughness,the practical applications of chitin-based hydrogels have been limited by their weak mechanical properties,such as cartilage repair and meniscus ***,we present the design and fabrication of chitin hydrogels with excellent mechanical strength and toughness by a dehydration and rehydration *** sequential dehydration and rehydration processes,the crystalline domains in the chitin hydrogels can be properly *** optimized crystallinity,the elastic modulus of the chitin hydrogels exceeds all previously reported values,and the fracture toughness is even comparable to some synthetic polymer hydrogels,while maintaining a high-water-content of about 80 wt.%.At the same water content,the mechanical properties of the chitin hydrogels are positively correlated with the hydrogel crystallinity,which proves that the change of mechanical properties of hydrogels is not simply dependent on weight *** hydrogels can be further strengthened by incorporating other biopolymers that are intrinsically weak,which makes the hydrogels promising for applications in fields such as cartilage repair and meniscus ***,the hydrogels enable loading and release of water-soluble and poorly water-soluble *** highly extendable strengthening and toughening strategy of chitin and chitin-based biopolymer hydrogels paves the way for their widely applications.

关键词： chitin hydrogel crystallinity rehydration chemical transformation strong and tough

Combustion characteristics of millimeter-sized aluminum particles in fluidized bed under various O_(2)/CO_(2)/H_(2)O atmospheres Author links open overlay panel

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Particuology 2024年第8期91卷 315-322页

作者： Jialing Zhou rui Zhang Dong liu Key Laboratory of Thermal Control of Electronic Equipment Ministry of Industry and Information TechnologyNanjing210094China Advanced Combustion Laboratory School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing210094China

Aluminum is an attractive alternative fuel,but it burns very inefficiently due to the formation of a dense Al_(2)O_(3)layer which prevents O_(2)from diffusion to the surface of Al *** previous experiments,the combustion of millimeter-sized Al(mAl)particles in the fluidized bed has achieved a substantial increase in the combustion efficiency,but further improvements are still *** this study,the effects of reaction atmosphere on the fluidized combustion of mAl particles were *** experiments with different O_(2)/H_(2)O/CO_(2)concentrations were *** experimental results indicate that the combustion efficiency of mAl particles in fluidized bed increases as the mole fraction of O_(2),H_(2)O or CO_(2)increases,and the highest combustion efficiency can reach 38.7%.After the analysis of the oxide film on the surface of aluminum particles,it was found that it is easier to generate the unstableθ-Al_(2)O_(3)under CO_(2)atmosphere,and it is easier to generate the unstableγ-Al_(2)O_(3)andθ-Al_(2)O_(3)under H_(2)O *** unstable Al_(2)O_(3)film is more likely to be abraded in the fluidized bed,which leads to the effective improvement of the combustion efficiency.

关键词： Al combustion Fluidized bed Atmosphere Combustion efficiency

Tunable Phase Structure of Side-chain Liquid Crystalline Polymers Enabled by Molecular Engineering of Dual Mesogenic Cores

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Chinese Journal of Polymer Science 2024年第10期42卷 1459-1469页

作者： Wen-huan Yao Lan-Sheng liu Jie Zhao Yan-Xia Wang An-Zhi Ma Zheng-rui Ma Lan-Ying Zhang Ruo-Chen Lan College of Chemistry and Chemical Engineering Hunan University Key Laboratory of Eco-Functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-Environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical Engineering Northwest Normal University Department of Materials Science and Engineering College of Engineering Peking University Institute of Advanced Materials & Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education College of Chemistry and Chemical Engineering Jiangxi Normal University

A series of novel side-chain liquid crystalline (SCLC) copolymers were synthesized by attaching two distinct mesogenic units, namely a chiral cholesteryl-based monomer (M1) and an achiral biphenyl-based monomer (M2), to a poly(3-mercaptopropylmethylsiloxane)(PMMS) backbone via thiol-ene click chemistry. The influence of side chain composition on the self-assembly behavior and phase structures of these SCLC copolymers was systematically investigated using different instrument. Results indicate that three distinct liquid crystalline phases and four unique molecular configurations were identified within the polymer series, with the emergence of the liquid crystalline phase being a synergistic outcome of the two distinct side chains. This study underscores the critical influence of side chain dimensions, rigidity, and spatial volume on the self-assembly structures and phase characteristics of liquid crystalline polymers, providing valuable insights for the rational design and development of advanced functional materials with tailored properties.

关键词： Chiral molar ratio Liquid crystalline copolymers Phase structure Self-assembly