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Chinese Journal of Catalysis 2024年第8期63卷 164-175页

作者： Chao Li Shuo Wang Yuan liub Xihe Huang Yan Zhuang Shuhong Wu Ying Wang Na Wen Kaifeng Wu Zhengxin Ding Jinlin Long State Key Laboratory of Photocatalysis on Energy and Environment College of ChemistryFuzhou UniversityFuzhou 350116FujianChina State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 110623LiaoningChina College of Chemistry Fuzhou UniversityFuzhou 350116FujianChina

Covalent organic frameworks(COFs)are promising materials for converting solar energy into green ***,limited charge separation and transport in COFs impede their application in the photocatalytic hydrogen evolution reaction(HER).In this study,the intrinsically tunable inter-nal bond electric field(IBEF)at the imine bonds of COFs was manipulated to cooperate with the internal molecular electric field(IMEF)induced by the donor-acceptor(D-A)structure for an effi-cient *** aligned orientation of IBEF and IMEF resulted in a remarkable H_(2)evolution rate of 57.3 mmol·g^(-1)·h^(-1)on TNCA,which was approximately 520 times higher than that of TCNA(0.11 mmol·g^(-1)·h^(-1))with the opposing electric field *** superposition of the dual electric fields enables the IBEF to function as an accelerating field for electron transfer,kinetically facilitat-ing the migration of photogenerated electrons from D to ***,theoretical calculations indicate that the inhomogeneous charge distribution at the C and N atoms in TNCA not only pro-vides a strong driving force for carrier transfer but also effectively hinders the return of free elec-trons to the valence band,improving the utilization of *** strategy of fabricating dual electric fields in COFs offers a novel approach to designing photocatalysts for clean energy synthesis.

关键词： Covalent organic framework Internal molecular electric field Internal bond electric field Photocatalysis Hydrogen evolution

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Integral sliding-mode robust observer-based congestion control for wireless access networks

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Journal of Control and Decision 2022年第2期9卷 152-164页

作者： Ladan Khoshnevisan Farzad R.Salmasia Xinzhi liub School of Electrical and Computer Engineering College of EngineeringUniversity of TehranTehranIran bDepartment of Applied Mathematics Faculty of MathematisUniversity of WaterlooWaterlooCanada

Designing a robust active queue management(RAQM)is mandatory to avoid congestion in networks with wireless access links,because transmission control protocol(TCP)can detect con-gestion after its occurrence in a communication network and wireless links suffer from bottleneck capacity variations caused by fading and packet error rate(PER)in the acknowledgement ***,the average window size cannot be measured explicitly from the output signal and input and state delay are imposed to a network,which complicate theRAQMdesign problem in nonlinear ***,the main contribution of this study is to design a robust observer based control procedure based on integral sliding mode protocol to estimate the average window size,to control congestion in a TCP/RAQM network and to compensate input and state ***-ulation results via professional simulator NS-2 and SIMULINK confirm that the procedure can effectively estimate the window size and can robustly avoid congestion.

关键词： Congestion control integral sliding mode robust active queue management(RAQM) robust observer-based control(ROBC) transmission control protocol(TCP) wireless access network

Amino-functionalized poloxamer 407 with both mucoadhesive and thermosensitive properties:preparation, characterization and application in a vaginal drug delivery system

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Acta Pharmaceutica Sinica B 2017年第5期7卷 593-602页

作者： Liqian Ci zhigang Huang Yu liub Zhepeng Liu Gang Wei Weiyue Lu School of Medical Instrument and Food Engineering University of Shanghai for Science and Technology Department of Pharmaceutics School of Pharmacy Fudan University & Key Laboratory of Smart Drug Delivery (Fudan University)Ministry of Education

Lack of mucoadhesive properties is the major drawback to poloxamer 407(F127)-based in situ hydrogels for mucosal administration. The objective of the present study was to construct a novel mucoadhesive and thermosensitive in situ hydrogel drug delivery system based on an aminofunctionalized poloxamer for vaginal administration. First, amino-functionalized poloxamer 407(F127-NH2) was synthesized and characterized with respect to its micellization behavior and interaction with mucin. Then using acetate gossypol(AG) as model drug, AG-loaded F127-NH2-based in situ hydrogels(NFGs) were evaluated with respect to rheology, drug release, ex vivo vaginal mucosal adhesion, in vivo intravaginal retention and local irritation after vaginal administration to healthy female mice. The results show that F127-NH2 is capable of forming a thermosensitive in situ hydrogel with sustained drug release properties. An interaction between positively charged F127-NH2 and negatively charged mucin wasrevealed by changes in the particle size and zeta potential of mucin particles as well as an increase in the complex modulus of NFG caused by mucin. Ex vivo and in vivo fluorescence imaging and quantitative analysis of the amount of AG remaining in mouse vaginal lavage all demonstrated greater intravaginal retention of NFG than that of an unmodified F127-based in situ hydrogel. In conclusion, amino group functionalization confers valuable mucoadhesive properties on poloxamer 407.

关键词： Poloxamer 407 Amino group Acetate gossypol In situ hydrogel Mucoadhesive gel

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A simple method for the isolation and purification of resveratrol from Polygonum cuspidatum

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Journal of Pharmaceutical Analysis 2013年第4期3卷 241-247页

作者： Dong-Geng Wanga Wen-Ying liub Guang-Tong Chena Medical School Nan Tong University Department of Pharmaceutical Analysis China Pharmaceutical University

Resveratrol, a polyphenol compound with strong biological activity, has been widely used in medicine, health products and cosmetic industries. It is also the main active component of Polygonurn cuspidatum, a well-known traditional Chinese medicine. We developed a simple and effective method for the preparation of resveratrol from P. cuspidatum. The whole preparative process consisted of reflux extraction, filtering, hydrolyzing, liquid-liquid extraction and eluting. Filtering is to remove non polar or less polar compounds and debris fragments from the extract. Hydrolyzing is to transform polydatin to resveratrol to improve the yield of resveratrol. Eluting is to remove impurities including strong acidic and water-soluble compounds. By acid hydrolysis of glycoside （polydatin）, the yield of resveratrol increased about 4-fold. The extraction recovery in different stages was high, and the content of resveratrol in the final product was over 73.8%. Compared with other methods reported, this technology is eco-friendly, easier to perform, and also has a lower cost.

关键词： Potygonum cuspidaturn Resveratrol Solvent extraction Purification

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Recent advances in functional nanomaterials for X-ray triggered cancer therapy

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Progress in Natural Science:Materials International 2020年第5期30卷 567-576页

作者： Teng Liu Kai Yang Zhuang Liu State Key Laboratory of Radiation Medicine and Protection School of Radiation Medicine and Protection & School for Radiological and Interdisciplinary Sciences (RADX) Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions Soochow University Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices Soochow University

X-ray is a form of ionizing radiation with high energy and strong tissue-penetrability, which has been widely used for cancer therapy, including radiation therapy(RT) as one of the mainstream cancer treatments and radiodynamic therapy(RDT) as an emerging treatment modality. However, the nonspecific absorption of X-ray and peculiar tumor microenvironment would lead to the unsatisfied therapeutic effect and severe damage to normal tissues. The fast progress of nanotechnology has provided great opportunities for the development of functional nanoparticles and strategies to solve these problems. In this review, we will summarize the recent advances in functional nanomaterials and the related strategies, discuss how they solve the challenges in order to improve the therapeutic efficacy and safety of RT and RDT, and moreover comment on the challenges and prospects for efficient X-ray triggered cancer therapy based on nanomedicine.

关键词： X-ray irradiation Nanomaterials Cancer therapy Radiation therapy Radiodynamic therapy

Thermal stability conditions of a weakly interacting Fermi gas in a weak magnetic field

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Progress in Natural Science:Materials International 2009年第1期19卷 121-124页

作者： Fudian Mena,Hui liub,Houyu Zhua a College of Physics Science and Technology,China University of Petroleum(East China),Dongying 257061,China b College of Science,Anhui Science and Technology University,Fengyang 233100,China College of Physics Science and Technology China University of Petroleum (East China) Dongying 257061 China College of Science Anhui Science and Technology University Fengyang 233100 China

On the basis of the results derived from pseudopotential method and ensemble theory,thermal stability of a weakly interacting Fermi gas in a weak magnetic field is studied by using analytical method of *** exact analytical expressions of stability conditions at different temperatures are given,and the effects of interactions as well as magnetic field on the stability of the system are *** is shown that there is an upperlimit magnetic field for the stability of the system at low temperatures,and there is an attractive dividing value at high *** attractive interaction is lower than the critical value,the stability of the system has no request for magnetic field,but if attractive interaction is higher than the dividing value,a lower-limit magnetic field exists for the stability of the system.

关键词： Fermi gas Interaction Heat capacity Stability

Coastal erosion in China under the condition of global climate change and measures for its prevention

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Progress in Natural Science:Materials International 2009年第4期19卷 415-426页

作者： Feng Caia, Xianze Su a, Jianhui liub, Bing Li b, Gang Lei a a Third Institute of Oceanography State Oceanic Administration, Xiamen 361005, China b College of Marine Geo-Science, Ocean University of China, Qingdao 266003, China Third Institute of Oceanography State Oceanic Administration Xiamen 361005 China College of Marine Geo-Science Ocean University of China Qingdao 266003 China

The general characteristics of coastal erosion in China are described in terms of the regional geography, the form of erosion, the causes of erosion, and the challenges we are facing. The paper highlights the relationship between coastal erosion and sea level rises, storm waves and tides, and the influence of global climate changes on coastal erosion along the coastal zone of China. The response of the risk of coastal erosion in China to climate changes has obvious regional diversity. Research into and the forecasting of the effects of climate changes on coastal erosion are systemic work involving the natural environment, social economy, and alongshore engineering projects in the global system. Facing global warming and continual enhancement of coastal erosion, suggestions for basic theoretical study, prevention technology, management system assurance, and strengthening the legal system are presented here.

关键词： Global climate changes Sea level rise Coastal erosion China

Finite element simulating of temperature and stress fields for linear friction welding of Ti6Al4V

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Finite element simulating of temperature and stress fields f...

Role of Notch expression in premature senescence of murine bone marrow stromal cells

第五届国际材料与热加工物理模拟及数值模拟学术会议

作者： Wende BUa Jinhe liub Northwestern Polytechnical University Xi’an 710072 China

The present paper concerns the variation of temperature and stress fields during the linear friction welding （LFW） process obtained by the thermo-mechanical coupled analysis method. A numerical model of LFW of Ti6Al4V is established, according to the characters of LFW and friction theory. In the model the thermal calculation is coupled to the mechanical solution. Meanwhile, the constitutive relation of Ti6Al4V in condition of large elasto-plastic deformation is taken into account. The law of variation of transient temperature fields and stress fields in different instant is systematically investigated. Accordingly, the calculation results of temperature field indicate that there is a very high heating rate and a steep gradient in the welded joint zone during the heating phase. The stress field of the welded joint is induced by uneven distribution of temperature and deformation degree. The calculation data of temperature is in good agreement with the experimental data measured by means of thermocouples at some points. In conclusion, the numerical model created in this study is effective to simulate thermo-mechanical process of LFW of Ti6Al4V. The information obtained form this numerical calculation work can provide a theory base for technical parameters optimization of the welding performance of LFW of Ti6Al4V.

关键词： Linear friction welding finite element simulation temperature field stress field thermo-mechanical analysis

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Progress in Natural Science:Materials International 2009年第5期19卷 557-562页

作者： Kejie Zhanga,b, Lifang Huang b, Hanying Sunb, Yan Zhub, Yi Xiaob, Mei Huang b, Wenli liub,a Department of Hematology, Zhongshan Hospital, Xiamen University, Fujian Medical University Clinic Teaching Hospital, Xiamen 361004, China b Department of Hematology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China Department of Hematology Zhongshan Hospital Xiamen University Fujian Medical University Clinic Teaching Hospital Xiamen 361004 China Department of Hematology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

The aim of the present study was to investigate the role of the Notch signaling pathway in premature senescence of murine bone marrow stromal cells in vitro. The intracellular domain of Notch 1 (ICN) was transfected into cultured murine bone marrow stromal cells by lipofectamine transfection. After three days, the proliferation of transfected cells was measured by MTT assay. Cell cycle distribution was analyzed by flow cytometry. Senescence-associated beta-galactosidase (SA-beta-gal) was measured, and the percentage of positive cells was evaluated by assessing 1000 cells in random fields of view. The expressions of p53 and p21Cip1/Waf1 were analyzed by both RT-PCR and Western blot analysis. The results showed that activation of Notch signaling inhibited proliferation of murine bone marrow stromal cells with induction of G1 arrest, increased the percentage of SA-beta-gal positive cells, and upregulated p53 and p21Cip1/Waf1 mRNA and protein expression levels. Thus, the activated Notch signaling could induce premature senescence of bone marrow stromal cells through the p53-p21Cip1/Waf1 pathway.

关键词： Bone marrow stromal cells Premature senescence Notch signaling pathway