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Chinese Chemical Letters 2007年第12期18卷 1487-1489页

作者： liang Yin Chao Feng Wang huan ling Wang rong li Jian Tai Ma College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 China

New Frechet-type dendritic BINOL ligands bearing several BINOL units at the periphery have been successfully synthesized. The （dendritic BINOL） Ti（IV） complexes were proved to be efficient catalysts for the enantioselective addition of diethylzinc to aromatic aldehydes. Moreover, these ligands could be quantitatively recovered and reused at least five times without a loss of the yield and enantioselectivity.

关键词： Asymmetric catalysis BINOL Aldehydes

Hybrid Luminescent Films Obtained by Covalent Anchoring Terbium Complex to Silica-based Network

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Chinese Chemical Letters 2002年第10期13卷 991-992页

作者： Feng Yi liU lian She FU Jun WANG huan rong li Hong Jie ZHANG Key Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022

New monomer N-(4-carboxyphenyl)-NL-(propyltriethoxysilyl)urea (1) which acts as both a ligand for Th3+ ion and a sol-gel precursor has been synthesized and characterized by H-1 NMR, and MS. Hybrid luminescent thin films consisting of organoterbium covalently bonded to a silica-based network have been obtained in situ via a sol-gel approach. Strong line emission of Tb3+ ion was observed from the hybrid luminescent films under UV excitation.

关键词： Hybrid thin film luminescence sol-gel.

Synthetic fungal melanin UV absorbers

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Science China Chemistry 2024年第9期67卷 3098-3110页

作者： Chao Wang rong Zhang Jianhua Zhang Xueqian Zhang Hengjie Zhang huan Cao Zhen Yang Yiwen li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China Department of Radiology Huaxi MR Research CenterFunctional and Molecular Imaging Key Laboratory of Sichuan ProvinceNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengdu 610041China

Agents with robust ultraviolet(UV)absorption capabilities play a vital role in safeguarding organisms and inorganic materials from UV ***,the synthetic procedures towards these UV absorbers are usually lengthy and complicated,accompanied by undesirable side reactions and the generation of toxic *** nature,allomelanin,a class of melanins variant found in melanized fungi near the Chernobyl nuclear power plant,plays crucial roles in the cell wall of melanized fungi,offering resistance to harsh external environments and promising UV resistance ***,allomelanin can be rapidly biosynthesized via the polymerization of 1,8-dihydroxynaphthalene in presence of enzymes in *** by this,we report here a green enzymatic polymerization strategy to efficiently and eco-friendly synthesize polydihydroxynaphthalene(PDHN)-based artificial allomelanin nanoparticles(NPs)with interesting *** calculations and experimental results demonstrated that the PDHN NPs exhibited excellent UVabsorption capacity,surpassing another widely used artificial melanin,polydopamine(PDA).Moreover,the light absorption mechanism of PDHN NPs was systematically elucidated for the first ***,the PDHN NPs were incorporated with polyvinyl alcohol(PVA)to create an anti-aging composite film with significantly enhanced UV shielding *** potential of these composite films in safeguarding plants from UV damage was meticulously ***,these PDHN NPs were first found to produce hydroxyl radicals(·OH)under UV irradiation,offering antibacterial properties that expand their potential applications.

关键词： melanin artificial allomelanin nanoparticles green synthesis UV absorption antibacterial

An efficient approach for the equivalent linearization of frame structures with plastic hinges under nonstationary seismic excitations

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 677-690页

作者： huang huan li Yingxiong li Yuyu College of Water Conservancy and Civil Engineering South China Agricultural UniversityGuangzhou 510642China Institute of Smart City and Intelligent Transportation Southwest Jiaotong UniversityChengdu 611756China

An efficient approach is proposed for the equivalent linearization of frame structures with plastic hinges under nonstationary seismic *** concentrated plastic hinges,described by the Bouc-Wen model,are assumed to occur at the two ends of a linear-elastic beam *** auxiliary differential equations governing the plastic rotational displacements and their corresponding hysteretic displacements are replaced with linearized differential ***,the two sets of equations of motion for the original nonlinear system can be reduced to an expanded-order equivalent linearized equation of motion for equivalent linear *** solve the equation of motion for equivalent linear systems,the nonstationary random vibration analysis is carried out based on the explicit time-domain method with high ***,the proposed treatment method for initial values of equivalent parameters is investigated in conjunction with parallel computing technology,which provides a new way of obtaining the equivalent linear systems at different time *** on the explicit time-domain method,the key responses of interest of the converged equivalent linear system can be calculated through dimension reduction analysis with high *** examples indicate that the proposed approach has high computational efficiency,and shows good applicability to weak nonlinear and medium-intensity nonlinear systems.

关键词： nonstationary random vibration plastic hinge equivalent linearization method explicit time-domain method parallel computation

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

A Two-stage Service-oriented Task Offloading Framework with Edge-cloud Collaboration:A Game Theory Approach

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Journal of Systems Science and Systems Engineering 2024年第5期33卷 521-551页

作者： Shiyong li Wenzhe li huan liu Wei Sun School of Economics and Management Yanshan UniversityQinhuangdao 066004

With the fast development of Mobile Internet,data traffic generated by end devices is anticipated to witness substantial growth in the future ***,processing tasks locally will cause latency due to the limited resources of the end ***-cloud collaboration,an effective solution for latency-sensitive applications,is attracting greater attention from both industry and *** combines the advantages of the cloud center with abundant computing resources and edge nodes with low-latency *** this paper,we propose a two-stage task offloading framework with edge-cloud collaboration to assist end devices processing latency-sensitive tasks either on the edge servers or in the cloud *** for homogeneous task offloading,in the first stage,the competitive end devices offload tasks to the edge *** formulate the selfish task offloading problem among end devices as a potential *** the second stage,the edge nodes request resources from the cloud center to process end devices tasks due to their limited ***,we consider the heterogeneous task offloading problem and use intelligent optimization algorithm to obtain the optimal offloading *** results show that the service prices of edge nodes influence the decisions and task offloading costs of end *** also verify the intelligent optimization algorithm can achieve optimal performance with low complexity and fast convergence.

关键词： Edge-cloud collaboration task offloading potential game simulation annealing algorithm

Enhanced properties of stone coal-based composite phase change materials for thermal energy storage

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 206-215页

作者： Baoshan Xie huan Ma Chuanchang li Jian Chen Key Laboratory of Renewable Energy Electric-Technology of Hunan Province School of Energy and Power EngineeringChangsha University of Science and TechnologyChangsha 410114China State Key Laboratory of Disaster Prevention and Reduction for Power Grid Changsha University of Science and TechnologyChangsha 410114China

Phase change materials (PCMs) can be incorporated with low-cost minerals to synthesize composites for thermal energy storage in building *** coal (SC) after vanadium extraction treatment shows potential for secondary utilization in composite *** prepared SC-based composite PCMs with SC as a matrix,stearic acid (SA) as a PCM,and expanded graphite (EG) as an *** combined roasting and acid leaching treatment of raw SC was conducted to understand the effect of vanadium extraction on promoting loading *** showed that the combined treatment of roasting at 900℃ and leaching increased the SC loading of the composite by 6.2%by improving the specific surface *** loading capacity and thermal conductivity of the composite obviously increased by 127%and 48.19%,respectively,due to the contribution of 3wt% *** data were supported by the high load of 66.69%and thermal conductivity of 0.59 W·m^(-1)·K-1of the designed *** obtained composite exhibited a phase change temperature of 52.17℃,melting latent heat of 121.5 J·g^(-1),and good chemical *** SC-based composite has prospects in building applications exploiting the secondary utilization of minerals.

关键词： thermal energy storage phase change material stone coal vanadium extraction secondary utilization

Application of Natural Medicinal Plants Active Ingredients in Oral Squamous Cell Carcinoma

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Chinese Journal of Integrative Medicine 2024年第9期30卷 852-864页

作者： REN Qun-li li Xiao-lan TIAN Tian li Shuang SHI rong-yi WANG Qian ZHU Yuan WANG Miao HU huan liU Jian-guo School of Stomatology Zunyi Medical UniversityZunyiGuizhou Province563000China Microbial Resources and Drug Development Key Laboratory of Guizhou Tertiary Institution Zunyi Medical UniversityZunyiGuizhou Province563000China School of Basic Medicine Zunyi Medical UniversityZunyiGuizhou Province563000China

Oral squamous cell carcinoma(OSCC)is the most common malignant cancer of the head and neck,with high morbidity and mortality,ranking as the sixth most common cancer in the *** treatment of OSCC is mainly radiotherapy,chemotherapy and surgery,however,the prognosis of patients is still poor and the recurrence rate is *** paper reviews the range of effects of natural medicinal plant active ingredients(NMPAIs)on OSCC cancer,including the types of NMPAIs,anti-cancer mechanisms,involved signaling pathways,and clinical *** NMPAIs include terpenoids,phenols,flavonoids,glycosides,alkaloids,coumarins,and volatile *** active ingredients inhibit proliferation,induce apoptosis and autophagy,inhibit migration and invasion of OSCC cells,and regulate cancer immunity to exert anti-cancer *** mechanism involves signaling pathways such as mitogen-activated protein kinase,phosphatidylinositol 3 kinase/protein kinase B,nuclear factor kappa B,miR-22/WNT1/β-catenin and Nrf2/***,NMPAIs can inhibit the growth of OSCC,and the combined drug is more *** medicinal plants are promising candidates for the treatment of OSCC.

关键词： natural medicinal plant active ingredients oral squamous cell carcinoma mechanism signaling pathway review

A molecular insight into coke formation process of vacuum residue in thermal cracking reaction

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Petroleum Science 2024年第3期21卷 2130-2138页

作者： Ji-Guang li Xin Guo huan-Di Hou Heavy Oil Processing Department Sinopec Research Institute of Petroleum Processing Co.LtdBeijing100083China

Understanding the coking behaviors has been considered to be really essential for developing better vacuum residue processing technologies.A battery of thermal cracking tests of typical vacuum residue at 410℃ with various reaction time were performed to evaluate the coke formation *** total yields of ideal components including naphtha,atmospheric gas oil(AGO)and vacuum gas oil(VGO)of thermal cracking reactions increased from 10.89%to 40.81%,and the conversion ratios increased from8.05%to 43.33%with increasing the reaction time from 10 to 70 *** asphaltene content increased from 12.14%to a maximum of 22.39%and then decreased,and this maximum of asphaltene content occurred at the end of the coking induction *** asphaltenes during the coking induction period,at the end and after coking induction period of those tested thermal cracking reactions were characterized to disclose the structure changing rules for coke formation process,and the coke formation pathways were discussed to reveal the coke formation process at molecular level.

关键词： Vacuum residue Thermal cracking Asphaltene Coking induction period Sulfur Nitrogen

Research on vibration energy harvesting technology of power equipment based on alternating magnet array

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High Voltage 2024年第2期9卷 336-345页

作者： Pinlei Lv Chengyu Fan Aijun Yang huan Yuan Jifeng Chu Mingzhe rong Xiaohua Wang State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anChina State Grid Sichuan Electric Power Research Institute ChengduChina

Vibration with a frequency of 100 Hz is widely distributed in the power equipment,and it can provide a new way to supply energy for sensors by vibration energy *** vibration energy harvesting method based on electromagnetic induction principle was studied through the arrayed structure of magnets and *** magnetic field models were established for four magnet array structures and it was found that the alternating magnet array has the largest magnetic flux and magnetic flux *** on the alternating magnet array,prototypes of energy harvester with vertical and parallel movement mode were *** structural parameter optimisation analysis,two different energy harvesters were fabricated and it was found that the energy harvester with a parallel movement mode has better output *** energy harvester could provide output voltage/current and power of 8.35 V/17.39 mA and 15.13 mW(matched resistance is 200Ω)at an acceleration of 5 m⋅s^(-2).The 100 mF capacitor could be charged to 2.72 V within 300 s,and the final voltage of the capacitor is greater than 3 V,which could sustainably drive commercial wireless temperature/humidity sensors.

关键词： power energy alternating