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Functionally Oriented Tumor Microenvironment Responsive Polymeric Nanoassembly:Engineering and Applications

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Chinese Journal of Polymer Science 2018年第3期36卷 273-287页

作者： wen-ming zhang Jian zhang Zhu Qiao Jun Yin Department of Polymer Science and Engineering School of Chemistry and Chemical EngineeringHefei University of Technology and Anhui Province Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei 230009China

The excellent drug encapsulation,prolonged in vivo circulation time,enhanced pharmacokinetics,and reduced adverse effects make the polymeric assemblies ideal carriers in nanomedicine,and become an emerging research field with rapid *** vivo,the polymer nanoassemblies will experience five steps,including circulation in the blood,accumulation in the tumoral site,penetration into the deep tumor tissue to reach cancer cells,internalization into cancer cells,and intracellular drug ***,although tremendous efforts have been made to the material design,currently available carriers still have difficulties in fulfilling all of the ***,the long-standing dilemma of the synchronized stability and permeability of vesicles is still a big challenge,which confused researchers for a long *** feature article tbcuses on the recent progress of single-or multi-stimuli triggered theranostic platforms,and the extracellularly reengineered shell-sheddable polymeric nanocarriers are systematically *** perspectives for future developments in the nanocarriers functioned with artificial helical polymers(the potential cell-penetrating peptides mimics)are also *** speculate that this feature article can fit the interesting of diverse readers and a guideline for the design of next generation of drug nanocarriers.

关键词： Block copolymers Tumor microenvironment responsive Self-assembly Theranostic Nanomedicine

Molecular Dynamics Analysis of the Effect of Laser and Defects on the Micro-Structure of Fused Silica

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Journal of Electronic Science and Technology 2020年第2期18卷 159-168页

作者： Li Li ming-wen zhang Zhe-Zhen Zhao School of Physics University of Electronic Science and Technology of ChinaChengdu 610054

In this work, the classic molecular dynamics simulations are employed to investigate the atomic structural modification of fused silica with defects as laser irradiation. The dynamics evolution of the atomic structure of fused silica is modeled during energy deposition. The structure parameters such as pair distribution functions(PDFs), bond angle distributions(BADs), and the coordination number are given. The calculated results reveal that fused silica undergoes significant changes in terms of Si-O, Si-Si, and O-O bond lengths, Si-O-Si and O-Si-O bond angles, and the Si and O coordination numbers during laser irradiation. The effects of different surface defects on the microstructure of fused silica are discussed too. The simulation results of molecular dynamics may help to understand the role of defects in the radiation effect of fused silica.

关键词： deposition. silica fused

Affinity Switching for Lysozyme and Dual-responsive Microgels by Stopped-flow Technique： Kinetic Control and Activity Evaluation

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Chinese Journal of Polymer Science 2017年第8期35卷 950-960页

作者： yun-zhu wu zhi-huang zhang xin han jian zhang wen-ming zhang 殷俊 Department of Polymer Science and Engineering School of Chemistry and Chemical Engineering Hefei University of Technology and Anhui Key Laboratory of Advanced Functional Materials and Devices Hefei 230009 China

The use of proteins as therapeutics in nanomedicine is an emerging research field and has developed ***,proteins are always vulnerable to renal excretion or digestion by the proteolytic system in vivo,which limits their usage to a large *** biocompatible polymers have been covalently linked to proteins to protect them from recognition by the immune system and prolong their circulation time,the biological activity of them is sometimes *** fill this gap,physical isolation,wrapping,or encapsulation techniques are *** to now,various mature examples were reported,but the whole time scales for guest molecules loading and releasing,especially the initial rapid loading process,were rarely ***,a series of dual-responsive poly（N-isopropylacrylamide-co-methacrylic acid）（P（NIPAM-co-MAA）） microgels were synthesized and employed to investigate the kinetics of in situ complexation and release of lysozyme under external stimuli modulation upon a stopped-flow apparatus,which was suitable for rapid dynamic *** inspection of the adsorption kinetics during the early stages（〈 50 s） revealed that the initial microgel collapse occurred within ~1 s,with more rapid transitions being observed when higher lysozyme concentrations were *** the dynamic traces could be well fitted with a double exponential function,suggesting a fast（τ1） and a slow（τ2） relaxation time,***,the kinetics of releasing bound lysozyme from microgels was carried on by utilizing the p H-responsive property,and the evaluation of the activity of released lysozyme was synchronously measured in a Micrococcus lysodeikticus（***） cell *** corresponding relaxation time（τ） was also calculated by fitting the recorded dynamic *** speculate that this work can provide basic dynamics data and theoretical basis for microgels based nanocarriers to be used for protein delivery,controlled release,and possible chemical sepa

关键词： responsive relaxation traces encapsulation lysozyme inspection Micrococcus fitting utilizing kinetics

Clean synthesis of calix[4]crown-5-sulfonyl cyclothiourea derivatives at room temperature in aqueous solution

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Chinese Chemical Letters 2009年第10期20卷 1166-1169页

作者： Cong wen Ding ming Jie zhang Ning Ma Chemistry Department of Science School Tianjin University Tianjin 300072 China

Calix[4]-crown-5-sulfonyl cyclothiourea derivatives 6 and 7 were synthesized from calix[4]-crown-5-monosulfonylethylenediamine derivatives 4 and 5 and carbon disulfide through nucleophilic addition and subsequent cyclization of intramolecule at room temperature in aqueous solution. The advantages of the novel protocol are the mild reaction condition, free organic solvent, simple final treatment, easy isolation of products and excellent yields.

关键词： Room temperature Aqueous solution Calix-crown-5-sttlfonyl cyclothiourea Clean synthesis

Connection between Volterra series and perturbation method in nonlinear systems analyses

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Acta Mechanica Sinica 2014年第4期30卷 600-606页

作者： Xing-Jian Dong Zhi-Ke Peng wen-ming zhang Guang Meng Institute of Vibration Shock & Noise Shanghai Jiao Tong University

This paper is concerned with the connection between the Volterra series and the regular perturbation method in nonlinear systems analyses. It is revealed for the first time that, for a forced polynomial nonlinear system, if its derived linear system is a damped dissipative system, the steady response obtained through the regular perturbation method is exactly identical to the response given by the Volterra series. On the other hand, if the derived linear system is an undamped conservative system, then the Volterra series is incapable of modeling the forced polynomial nonlinear system. Numerical examples are further presented to illustrate these points. The results provide a new criterion for quickly judging whether the Volterra series is applicable for modeling a given polynomial nonlinear system.

关键词： Volterra series · Regular perturbation method ·Polynomial nonlinear systems · Nonlinear Vibration

Revelation of bimolecular tautomerization induced by the concerted and radical interactions in lignin pyrolysis

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能源化学:英文版 2023年第9期84卷 1-10页

作者： wen-luan Xie Bin Hu wen-ming zhang He-long Li Guo-yong Song Ji Liu Qiang Lu National Engineering Research Center of New Energy Power Generation North China Electric Power UniversityBeijing 102206China Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing 100083China Suzhou Institute of North China Electric Power University Suzhou 215123JiangsuChina

Bimolecular interactions play crucial roles in lignin *** tautomerization of key intermediates has a significant impact on the formation of stable products,whereas bimolecular tautomerization has been rarely *** the present work,the bimolecular tautomerization mechanism induced by both concerted and radical interactions was proposed and carefully confirmed.A characteristicβ-O-4 lignin dimer,2-phenoxy-1-phenylethanol(α-OH-PPE),was used as the model compound to reveal two representative keto-phenol and enol-keto tautomerism mechanisms,based on theoretical calculations combined with pyrolysis *** results indicate that the unimolecular tautomerism as the rate-determining step limits product generation,due to fairly high energy *** the free hydroxy compounds and radicals derived from initial pyrolysis can further initiate bimolecular tautomerism reactions through the one-step concerted hydroxyl-assisted hydrogen transfer(hydroxylAHT)and two-step radical hydrogen abstraction interactions,*** alleviating and even avoiding the large ring tension of tautomerism,the unstable tautomers(2,4-cyclohexadienone and1-hydroxy styrene)can be rapidly tautomerized into stable phenol and acetophenone with the help of intermolecular *** from the significant advantage of retro-ene fragmentation in breaking theβ-O-4 bond to form tautomers,a large amount of stable phenolic and ketone products can be generated following bimolecular tautomerization in the pyrolysis ofβ-O-4 linked lignin.

关键词： Lignin pyrolysis Interaction mechanism Tautomerism Hydroxyl-assisted hydrogen transfer Radical chain reaction

Subchronic Toxicity Study on Soy Isoflavones in Rats

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Biomedical and Environmental Sciences 2009年第3期22卷 259-264页

作者： wen-ZHONG zhang wen-ming CUI XIN zhang WEI WANG XU-DONG JIA XIAO-PENG zhang NING LI Institute of Nutrition and Food Safety Chinese Center for Disease Control and Prevention Beijing 100021 China

Objective To investigate the subchronic toxicity of soy isoflavones （SIF） in male rats. Method Fifty Sprague-Dawley rats were randomly divided into 5 groups, 10 rats per group. SIF were given to rats in different groups by gavage at dose of 0, 0.2, 0.5, 1.5, and 4.5 g/kg bw, respectively for 13 weeks. Clinical manifestations, body weight, and food consumption were observed weekly. At the end of the study, urinalysis, hematology, clinical chemistry, total testosterone, and follicle-stimulating hormone were tested, and histopathological examinations were performed. Results No mortality, ophthalmic abnormalities or treatment-related clinical signs were identified during the study. As compared with the control group, significantly lower body weights and food consumption were observed in 1.5 and 4.5 g/kg bw groups. In clinical chemistry tests, triglyceride was significantly decreased and high-density lipoprotein cholesterol was significantly increased in all SIF-treated groups. Total testosterone levels were significantly lower in 0.50, 1.50, and 4.5 g/kg bw dose groups than in the control group. Microscopic examination showed that the mammary glands exhibited hyperplasia and excreted latex in rats of the 4.5 g/kg bw group. No changes attributable to treatment of SIF in other parameters were found. Conclusion SIF at high dosages caused significant endocrine disruption in male rats. The no observed adverse effect level （NOAEL） of SIF to male rats in this study is considered to be 0.20 g/kg bw.

关键词： Soy isoflavone Rat Subchronic toxicity

Parametric characteristic of the random vibration response of nonlinear systems

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Acta Mechanica Sinica 2013年第2期29卷 267-283页

作者： Xing-Jian Dong Zhi-Ke Peng wen-ming zhang Guang Meng Fu-Lei Chu State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Department of Precision Instruments Tsinghua University

Volterra series is a powerful mathematical tool for nonlinear system analysis,and there is a wide range of nonlinear engineering systems and structures that can be represented by a Volterra series *** the present study,the random vibration of nonlinear systems is investigated using Volterra *** expressions were derived for the calculation of the output power spectral density（PSD） and input-output cross-PSD for nonlinear systems subjected to Gaussian *** on these expressions,it was revealed that both the output PSD and the input-output crossPSD can be expressed as polynomial functions of the nonlinear characteristic parameters or the input *** studies were carried out to verify the theoretical analysis result and to demonstrate the effectiveness of the derived *** results reached in this study are of significance to the analysis and design of the nonlinear engineering systems and structures which can be represented by a Volterra series model.

关键词： Volterra series·Nonlinear system·Random vibration·Power spectrum density·Generalized frequency response functions

Effect of ultrasonic melt treatment on degassing of Mg-6Zn-1Ca alloy

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China Foundry 2015年第1期12卷 15-19页

作者： Zheng Jia wen-ming zhang Fu Yang Zhi-qiang zhang Qi-chi Le Jian-zhong Cui College of Mechanical Engineering Shenyang University Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern University

The effect of ultrasonic power and treatment time on degassing of Mg-6Zn-1Ca alloy was studied in this paper. The degassing effect was characterized by measuring densities of ingots. The results show that proper ultrasonic treatment can remove hydrogen from the melt of the Mg-6Zn-1Ca alloy. The ultrasonic degassing effect is closely related to the ultrasonic power density and treatment time. The degassing efficiency increases with an increase in ultrasonic power density when the melt is treated at 690 °C for 120 s, reaching its highest value at 1.2 W·cm-3. When the power density is 1.2 W·cm-3, with an increase in ultrasonic treatment time, the degassing efficiency increases at first, reaches its peak value at 120 s, then decreases as the ultrasonic treatment is further prolonged. In this experiment, the optimum degassing effect with an efficiency of 67.5 % is obtained by ultrasonic treatment with the power density of 1.2 W·cm-3 for 120 s. The maximum density of ingot can be increased from 1.8069 g·cm-3 to 1.8146 g·cm-3(increased by 0.43%).

关键词： ultrasonic treatment degassing efficiency Mg-6Zn-1Ca alloy cavitation