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The chemical composition, quality control and pharmacological effects of Gualou-Xiebai-Banxia Decoction: a review
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作者 Yan-Tao Wang Yin-Yan Lai +4 位作者 Li Wang Xiao-Li Zheng Hong-Ju Li Su-Hong Chen Zheng Xiang 《Traditional Medicine Research》 2025年第4期72-82,共11页
Gualou-Xiebai-Banxia Decoction(GXBD)is a traditional Chinese herbal formula including four traditional Chinese medicines:Gualou(Trichosanthis Fructus,TF),Xiebai(Allii Macrostemonis Bulbus,AMB),Banxia(Pinelliae Rhizoma... Gualou-Xiebai-Banxia Decoction(GXBD)is a traditional Chinese herbal formula including four traditional Chinese medicines:Gualou(Trichosanthis Fructus,TF),Xiebai(Allii Macrostemonis Bulbus,AMB),Banxia(Pinelliae Rhizoma,PR)and yellow wine.It is a classical therapy for chest stuffiness and pain syndrome and is widely used in the clinical treatment of coronary heart disease.It also shows significant therapeutic effects on pulmonary heart disease,hyperlipidemia,and arrhythmia.This study conducted a literature review and collected information on GXBD from databases such as PubMed,Web of Science,China National Knowledge Infrastructure,and ScienceDirect.The result indicated that the main active ingredients of GXBD are steroids,flavonoids,terpenoids,alkaloids,amino acids,and organic acids.Trigonelline,macrostemonoside and cucurbitacin B can provide reference for its quality control.GXBD may exert therapeutic effects on coronary heart disease through AMPK,PI3K-AKT,oxLDL,VEGF,and NF-κB signal pathways.This review provides a comprehensive analysis and summary of the chemical composition and in vivo metabolism of three traditional Chinese medicines(TF,AMB,and PR),along with an evaluation of the chemical composition,quality control,pharmacological effects,and clinical application of GXBD.Based on these,areas requiring further research on GXBD have been proposed to provide a reference for its further development and new drug research. 展开更多
关键词 Gualou-Xiebai-Banxia Decoction chemical composition chest stuffiness quality control pharmacological mechanism
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Theory and Practice of Oxide Inclusion Composition and Morphology Control in Spring Steel Production 被引量:5
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作者 XUEZheng-liang LIZheng-bang +3 位作者 ZHANGJia-wen YANGWu GANChao-fu WANGYu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2003年第2期38-44,共7页
In order to control the composition,morphology and size distribution of oxide inclusions in spring steel,the relationship between the content or activity of aluminum and calcium in molten steel and compositions of oxi... In order to control the composition,morphology and size distribution of oxide inclusions in spring steel,the relationship between the content or activity of aluminum and calcium in molten steel and compositions of oxide inclusion precipitated at different temperatures was determined based on thermodynamic equilibrium for spring steel 60Si2 MnA,and has been verified by practice.The size distribution of non-metallic inclusions electrolytically extracted from specimens of hot rolled spring steel was determined by image analyzer.The results show that there are a great deal of large inclusions in spring steel produced by the conventional process,and the quantity and the size of large inclusions in spring steel produced by new process are largely reduced.As a result,the fatigue properties of the spring steel produced by new process are highly improved,and the ratio ofσ-1/σbis raised from 0.451 to 0.468. 展开更多
关键词 spring steel oxide inclusion inclusion composition control inclusion morpholo-gy control fatigue limit strength
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Gypsum-based Silica Gel Humidity-controlling Composite Materials:Preparation,Characterization,and Performance
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作者 李曦 冉茂宇 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期337-344,共8页
Gypsum was used as substrate,and silica gel was mixed into substrate at a certain mass ratio to prepare humidity-controlling composites;moreover,the moisture absorption and desorption properties of gypsum-based compos... Gypsum was used as substrate,and silica gel was mixed into substrate at a certain mass ratio to prepare humidity-controlling composites;moreover,the moisture absorption and desorption properties of gypsum-based composites were compared with adding different silica gel particle size and proportion.The morphological characteristics,the isothermal equilibrium moisture content curve,moisture absorption and desorption rate,moisture absorption and desorption stability,and humidity-conditioning performance were tested and analyzed.The experimental results show that,compared with pure-gypsum,the surface structure of the gypsum-based composites is relatively loose,the quantity,density and aperture of the pores in the structure increase.The absorption and desorption capacity increase along with the increase of silica gel particle size and silica gel proportion.When 3 mm silica gel particle size is added with a mass ratio of 40%,the maximum equilibrium moisture content of humidity-controlling composites is 0.161 g/g at 98% relative humidity(RH),3.22 times that of pure-gypsum.The moisture absorption and desorption rates are increased,the equilibrium moisture absorption and desorption rates are 2.68 times and 1.61 times that of pure-gypsum at 58.5% RH,respectively.The gypsum-based composites have a good stability,which has better timely response to dynamic humidity changes and can effectively regulate indoor humidity under natural conditions. 展开更多
关键词 humidity controlling composite materials GYPSUM silica gel
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Composition control and temperature inferential control of dividing wall column based on model predictive control and PI strategies 被引量:2
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作者 Jianxin Wang Na Yu +2 位作者 Mengqi Chen Lin Cong Lanyi Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第5期1087-1101,共15页
The dividing wall column (DWC) is considered as a major breakthrough in distillation technology and has good prospect of industrialization. Model predictive control (MPC) is an advanced control strategy that has a... The dividing wall column (DWC) is considered as a major breakthrough in distillation technology and has good prospect of industrialization. Model predictive control (MPC) is an advanced control strategy that has acquired extensive applications in various industries. In this study, MPC is applied to the process for separating ethanol, n-propanol, and n-butanol ternary mixture in a fully thermally coupled DWC. Both composition control and tem- perature inferent/al control are considered. The multiobjective genetic algor/thm function "gamult/obj" in Matlab is used for the weight tuning of MPC. Comparisons are made between the control performances of MPC and PI strategies. Simulation results show that although both MPC and PI schemes can stabilize the DWC in case of feed disturbances, MPC generally behaves better than the PI strategy for both composition control and tempera- ture inferential control, resulting in a more stable and superior performance with lower values of integral of squared error (ISE). 展开更多
关键词 Dividing wall column composition control Temperature inferential control PI strategy Model predictive control Genetic algorithm
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Composition-controlled synthesis of platinum and palladium nanoalloys as highly active electrocatalysts for methanol oxidation 被引量:4
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作者 Haiqiang Zhao Weihong Qi +2 位作者 Xinfeng Zhou Haofei Wu Yejun Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第2期342-349,共8页
Platinum and palladium(PtPd)alloy nanoparticles(NPs)are excellent catalysts for direct methanol fuel cells.In this study,we developed PtPd alloy NPs through the co‐reduction of K2PtCl4and Na2PdCl4in a polyol synthesi... Platinum and palladium(PtPd)alloy nanoparticles(NPs)are excellent catalysts for direct methanol fuel cells.In this study,we developed PtPd alloy NPs through the co‐reduction of K2PtCl4and Na2PdCl4in a polyol synthesis environment.During the reaction,the feed molar ratio of the two precursors was carried over to the final products,which have a narrow size distribution with a mean size of approximately4nm.The catalytic activity for methanol oxidation reactions possible depends closely on the composition of as‐prepared PtPd alloy NPs,and the NPs with a Pt atomic percentage of approximately75%result in higher activity and stability with a mass specific activity that is7times greater than that of commercial Pt/C catalysts.The results indicate that through composition control,PtPd alloy NPs can improve the effectiveness of catalytic performance. 展开更多
关键词 Platinum and palladium alloy nanoparticles composition and size control Methanol oxidation
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Controllable thermal rectification design for buildings based on phase change composites
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作者 Hengbin Ding Xiaoshi Li +2 位作者 Tianhang Li Xiaoyong Zhao He Tian 《Journal of Semiconductors》 EI CAS CSCD 2024年第2期40-45,共6页
Phase-change material(PCM)is widely used in thermal management due to their unique thermal behavior.However,related research in thermal rectifier is mainly focused on exploring the principles at the fundamental device... Phase-change material(PCM)is widely used in thermal management due to their unique thermal behavior.However,related research in thermal rectifier is mainly focused on exploring the principles at the fundamental device level,which results in a gap to real applications.Here,we propose a controllable thermal rectification design towards building applications through the direct adhesion of composite thermal rectification material(TRM)based on PCM and reduced graphene oxide(rGO)aerogel to ordinary concrete walls(CWs).The design is evaluated in detail by combining experiments and finite element analysis.It is found that,TRM can regulate the temperature difference on both sides of the TRM/CWs system by thermal rectification.The difference in two directions reaches to 13.8 K at the heat flow of 80 W/m^(2).In addition,the larger the change of thermal conductivity before and after phase change of TRM is,the more effective it is for regulating temperature difference in two directions.The stated technology has a wide range of applications for the thermal energy control in buildings with specific temperature requirements. 展开更多
关键词 phase change composites controllable thermal rectification building applications
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Design and control of chemical compositions for high-performance austempered ductile iron 被引量:2
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作者 Gong Wenbang Chen Guodong +2 位作者 Luo Li Hao Jing Zhang Zhonghe 《China Foundry》 SCIE CAS 2012年第2期143-147,共5页
This paper presents the effects of chemical compositions of austempered ductile iron (ADI) on casting quality, heat treatment process parameters and mechanical properties of final products. Through experiment and pr... This paper presents the effects of chemical compositions of austempered ductile iron (ADI) on casting quality, heat treatment process parameters and mechanical properties of final products. Through experiment and production practice, the impacts of carbon equivalent on ADI and its mechanical properties have been studied. Proper content ranges for carbon and silicon have been obtained to avoid ADI casting shrinkage and graphite fioatation, as well as to achieve the optimal mechanical properties. According to the impact of silicon content on austenite phase transformation, the existing form of carbon in ADI has been analyzed, and also the formula and diagram showing the relationship between austenitizing temperature and carbon content in austenite have been deduced. The chemical composition range for high performance ADI and its control points have been recommended, to serve as a reference for production process. 展开更多
关键词 austempered ductile iron chemical composition composition control
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EXPERT SYSTEM FOR SINTER CHEMICAL COMPOSITION CONTROL BASED ON ADAPTIVE PREDICTION 被引量:1
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作者 Fan Xiaohui Wang Haidong +4 位作者 Chen Jin Huang Tianzheng Yang Shinong Wang Yueli Zheng Tianzhong 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 1996年第1期47-50,共4页
In order to stabilize the sinter chemical composition,the expert system for composition control based on adaptive prediction has been developed on the basis of modern control theory and artificial intelligence.It has ... In order to stabilize the sinter chemical composition,the expert system for composition control based on adaptive prediction has been developed on the basis of modern control theory and artificial intelligence.It has been verified by using real data at No.3 Sintering Plant of Anshan Iron and Steel Co.,and satisfactory results have been obtained. 展开更多
关键词 SINTER chemical composition adaptive prediction expert system for control
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A Feedforward Controller to Regulate the Chemical Composition of Molten Steel in a Continuous Casting Tundish
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作者 Miguel A. Barron Dulce Yolotzin Isaias Hilerio 《Intelligent Control and Automation》 2013年第3期245-249,共5页
A feedforward controller for the automatic regulation of chemical composition of molten steel in the tundish of a continuous casting machine is proposed in this work. The flow of molten steel inside the tundish is mod... A feedforward controller for the automatic regulation of chemical composition of molten steel in the tundish of a continuous casting machine is proposed in this work. The flow of molten steel inside the tundish is modeled as a distributed parameter system, and the resulting partial differential equation is transformed into a set of ordinary differential equations by means of the finite differences technique. From the above set and using a proper boundary condition, a feedforward control law is synthesized. No experimental tests are reported, however, the dynamic performance of the controller is illustrated by means of numerical simulations. 展开更多
关键词 Chemical composition Continuous CASTING Distributed Parameter System FEEDFORWARD controller MOLTEN Steel TUNDISH
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Composite control for coagulation process with time delay and disturbances
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作者 牛丹 陈夕松 +1 位作者 杨俊 周杏鹏 《Journal of Southeast University(English Edition)》 EI CAS 2016年第3期285-292,共8页
A composite control scheme consisting of modepredictive control (MPC) and disturbance observer (DOB) iproposed to solve the control performance degradationproblem of the turbidity of the treated water in the prese... A composite control scheme consisting of modepredictive control (MPC) and disturbance observer (DOB) iproposed to solve the control performance degradationproblem of the turbidity of the treated water in the presence osignificant changes in raw water quality, water flow rate andinternal model mismatch disturbances. The MPC is employedas a feedback controller for the coagulation process with alarge time delay. The DOB is adopted to estimate the severedisturbances in the turbidity control, such as large changes inraw water quality and water flow rate. The estimated valuesare applied for feed-forward compensation to rejecdisturbances. Finally, the disturbance rejection performancesfor step disturbances and time-varying disturbances in thenominal case and model mismatch case are tested. Thesimulation results illustrate that, compared with the MPCmethod, the proposed method can significantly improve thedisturbance rejection performance in the turbidity control othe treated water, no matter if in the presence of externadisturbances or internal model mismatch disturbances. 展开更多
关键词 disturbance observer composite control coagulant dosage disturbance rejection
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Reachability analysis of web service compositions via NWA 被引量:1
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作者 杜旭涛 邢春晓 周立柱 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期293-295,共3页
In order to improve the design and implementation quality of web service compositions,formal methods are used to model them and certain properties are verified.WCFA (web service interface control flow automata)is us... In order to improve the design and implementation quality of web service compositions,formal methods are used to model them and certain properties are verified.WCFA (web service interface control flow automata)is used to model web services,especially the control flow and possible interactions with other web services.A web service composition consists of a set of interacting WCFA.The global behavior of web service compositions is captured by NWA(nested word automata).A variation of the depth-first search algorithm is used to transform a set of WCFA into an NWA.State formulae and call stacks at each node of NWA are computed by a path-sensitive reachability analysis.Safety properties,call stack inspection properties and pre/post-conditions of service invocations are described by assertions.Then verification of these assertions is carried out by an automated SAT tool. 展开更多
关键词 web service composition FORMALISM nested word automata (NWA) web service interface control flow automata (WCFA) VERIFICATION
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Highly active mixed-phase TiO_2 photocatalysts fabricated at low temperature and the correlation between phase composition and photocatalytic activity 被引量:10
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作者 SHI, Lei WENG, Duan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第10期1263-1267,共5页
The idea of varying volume ratio of water to ethanol in solvent was firstly employed to yield phase composition controllable mixed- phase titanium dioxide (TiO2) photocatalysts via a low temperature solvothermal route... The idea of varying volume ratio of water to ethanol in solvent was firstly employed to yield phase composition controllable mixed- phase titanium dioxide (TiO2) photocatalysts via a low temperature solvothermal route at 353 K. It was found that anatase contents increase from 0 to 100% with increase of ethanol contents in solvent. The mixed-phase TiO2 with 60% anatase content exhibited the best photocatalytic activity in photodecomposing formaldehyde (FAD) under UV light irradiation, which increases by abou... 展开更多
关键词 titanium dioxide solvothermal synthesis phase compositional control synergistic effect PHOTOCATALYSIS
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The Controllability, Observability, and Stability Analysis of a Class of Composite Systems with Fractional Degree Generalized Frequency Variables 被引量:2
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作者 Cuihong Wang Yafei Zhao YangQuan Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第3期859-864,共6页
This paper is concerned with fundamental properties of a class of composite systems with fractional degree generalized frequency variables, including controllability, observability and stability. Firstly, some necessa... This paper is concerned with fundamental properties of a class of composite systems with fractional degree generalized frequency variables, including controllability, observability and stability. Firstly, some necessary and sufficient conditions are given to guarantee controllability and observability of such composite systems. Then we prove that the stability problem of such composite systems can be reduced to judging whether a fractional degree polynomial is stable. Finally, the stability analysis result is applied in the supervisory control of fractional-order multi-agent systems, and an example is provided to illustrate the effectiveness of the proposed methods. 展开更多
关键词 composite SYSTEM controlLABILITY fractionalorder SYSTEM OBSERVABILITY stability
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Synthesis and analysis of new humidity-controlling composite materials 被引量:2
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作者 Jian-li Shang Zhi-fang Zong Hao Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第5期594-602,共9页
Gypsum is a traditional building material. To improve the humidity-controlling properties of gypsum, we prepared a new type of humidity-controlling composite using the sol-gel method. Methods to determine the maximum ... Gypsum is a traditional building material. To improve the humidity-controlling properties of gypsum, we prepared a new type of humidity-controlling composite using the sol-gel method. Methods to determine the maximum equilibrium moisture content and speed of adsorption/desorption were subsequently applied to analyze the performance of the samples. The appearance and structural properties of the samples were characterized by scanning electronic microscopy (SEM). The experimental results show that the humidity-controlling gel with added LiCl exhibits high moisture storage and that the equilibrium maximum moisture content is 5.652 g/g at a 75.29% relative humidity (RH). A mass ratio of LiCl/sol = 0.15 is demonstrated to be appropriate for the preparation of the new humidity-controlling composites. A coarse network with tiny pores is observed on the surface of the new humidity-controlling composites, and this pore network provides sufficient space for moisture adsorption. 展开更多
关键词 composite materials GYPSUM humidity control sol-gel processing ADSORPTION DESORPTION
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Magneto-rheological elastomer (MRE) based composite structures for micro-vibration control 被引量:2
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作者 YQ Ni ZG Ying ZH Chen 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第3期345-356,共12页
Magneto-rheological elastomers (MILEs) are used to construct composite structures for micro-vibration control of equipment under stochastic support-motion excitations. The dynamic behavior of MREs as a smart viscoel... Magneto-rheological elastomers (MILEs) are used to construct composite structures for micro-vibration control of equipment under stochastic support-motion excitations. The dynamic behavior of MREs as a smart viscoelastic material is characterized by a complex modulus dependent on vibration frequency and controllable by external magnetic fields. Frequency-domain solution methods for stochastic micro-vibration response analysis of the MRE-based structural systems are developed to derive the system frequency-response function matrices and the expressions of the velocity response spectrum. With these equations, the root-mean-square (RMS) velocity responses in terms of the one-third octave frequency band spectrum can be calculated. Further, the optimization problem of the complex moduli of the MRE cores is defined by minimizing the velocity response spectra and the RMS velocity responses through altering the applied magnetic fields. Simulation results illustrate the influences of MRE parameters on the RMS velocity responses and the high response reduction capacities of the MRE-based structures. In addition, the developed frequency-domain analysis methods are applicable to sandwich beam structures with arbitrary cores characterized by complex shear moduli under stochastic excitations described by power spectral density functions, and are valid for a wide frequency range. 展开更多
关键词 magneto-rheological elastomer (MRE) micro-vibration control EQUIPMENT composite structure sandwich beam stochastic excitation
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Nonlinear dynamic characteristics and optimal control of a giant magnetostrictive film-shaped memory alloy composite plate subjected to in-plane stochastic excitation 被引量:2
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作者 竺致文 张庆昕 许佳 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期165-171,共7页
The nonlinear dynamic characteristics and optimal control of a giant magnetostrictive film (GMF)-shaped memory alloy (SMA) composite plate subjected to in-plane stochastic excitation are studied. GMF is prepared b... The nonlinear dynamic characteristics and optimal control of a giant magnetostrictive film (GMF)-shaped memory alloy (SMA) composite plate subjected to in-plane stochastic excitation are studied. GMF is prepared based on an SMA plate, and combined into a GMF-SMA composite plate. The Van der Pol item is improved to explain the hysteretic phenomena of GMF and SMA, and the nonlinear dynamics model of a GMF-SMA composite cantilever plate subjected to in-plane stochastic excitation is developed. The stochastic stability of the system is analyzed, and the steady-state probability density function of the dynamic response of the system is obtained. The condition of stochastic Hopf bifurcation is discussed, the reliability function of the system is provided, and then the probability density of the first-passage time is given. Finally, the stochastic optimal control strategy is proposed by the stochastic dynamic programming method. Numerical simulation shows that the stability of the trivial solution varies with bifurcation parameters, and stochastic Hopf bifurcation appears in the process; the system's reliability is improved through stochastic optimal control, and the first- passage time is delayed. A GMF-SMA composite plate combines the advantages of GMF and SMA, and can reduce vibration through passive control and active control effectively. The results are helpful for the engineering applications of GMF-SMA composite plates. 展开更多
关键词 giant magnetostrictive film shape memory alloy composite cantilever plate stochastic Hopf bifurcation optimal control
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Halloysite Nanotube Composited Thermo-responsive Hydrogel System for Controlled-release 被引量:3
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作者 林茜 巨晓洁 +3 位作者 谢锐 江明月 魏竭 褚良银 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第9期991-998,共8页
Halloysite nanotube-composited thermo-responsive hydrogel system has been successfully developed for controlled drug release by copolymerization of N-isopropylacrylamide (NIPAM) with silane-modified halloysite nanot... Halloysite nanotube-composited thermo-responsive hydrogel system has been successfully developed for controlled drug release by copolymerization of N-isopropylacrylamide (NIPAM) with silane-modified halloysite nanotubes (HNT) through thermally initiated free-radical polymerization. With methylene blue as a model drug, thermo-responsive drug release results demonstrate that the drug release from the nanotubes in the composited hy-drogel can^be well controlled by manipulating the environmental temperature. When the hydrogel network is swol- len at temperature below the lower critical solution temperature (LCST), drug releases steadily from lumens of the embedded nanotubes, whereas the drug release stops when hydrogel shrinks at temperature above the LCST. The release of model drug from the HNT-composited hydrogel matches well with its thermo-responsive volume phasetransition, and shows characteristics of well controlled release. The design strategy and release results of the pro- posed novel HNT-composited thermo-responsive hydrogel system provide valuable guidance for designing respon- s_i_ve nanocomposites for controlled-release of active agents. 展开更多
关键词 halloysite nanotube composite hydrogel controlled release thermo-responsive carder poly(N-iso-propylacrylamide)
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Coating thickness control in continuously fabricating metallic glass-coated composite wires 被引量:1
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作者 Bao-yu Zhang Xiao-hua Chen +1 位作者 Zhao-ping Lu Xi-dong Hui 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2013年第5期456-461,共6页
A continuous production process was developed for coating bulk metallic glasses on the metallic wire surface. The effects of processing parameters, including the drawing velocity and coating temperature, on the coatin... A continuous production process was developed for coating bulk metallic glasses on the metallic wire surface. The effects of processing parameters, including the drawing velocity and coating temperature, on the coating thickness were investigated. It is found that the coating thickness increases with the increase in drawing velocity but decreases with the increase in coating temperature. A fluid mechanical model was developed to quantify the coating thickness under various processing conditions. By using this theoretical model, the coating thickness was calculated, and the calculated values are in good agreement with the experimental data. 展开更多
关键词 composite materials metallic glass COATINGS thickness control
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ADVANCED QUALITY CONCEPTS AND COMPOSITE RELIABILITY THROUGH STATISTICALPROCESS CONTROL 被引量:1
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作者 D. Evans (CCLRC, Rutherford Appleton Laboratory, Chilton, Oxon. OX14 2HQ U.K.) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1997年第3期263-269,共7页
The physical properties of thermosetting resins and resin based composites may be influenced by changes in any one of the mang formulating or process related variables involved in their manufacture. When resins and co... The physical properties of thermosetting resins and resin based composites may be influenced by changes in any one of the mang formulating or process related variables involved in their manufacture. When resins and composite materials are required to perform in aggressive environments, reliable and predicable performance is essential and therefore these materials must be prepared and tested in accorkance with a strictquality plan. This paper outlines the elements of statistical process control (S.P.C.)as it may be applied to non-metallic materials and discusses the concept of Capability Index (Cp). 展开更多
关键词 physical property compositE process control cryogenic application
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Failure analysis and control measures of deep roadway with composite roof:a case study 被引量:2
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作者 Yongliang Li Renshu Yang +4 位作者 Shizheng Fang Hai Lin Shaojie Lu Ye Zhu Maosheng Wang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第1期120-137,共18页
There is great variation in the lithology and lamination thickness of composite roof in coal-measure strata;thus,the roof is prone to delamination and falling,and it is difficult to control the surrounding rock when d... There is great variation in the lithology and lamination thickness of composite roof in coal-measure strata;thus,the roof is prone to delamination and falling,and it is difficult to control the surrounding rock when developing roadway in such rock strata.In deep mining,the stress environment of surrounding rock is complex,and the mechanical response of the rock mass is different from that of the shallow rock mass.For composite-roof roadway excavated in deep rock mass,the key to safe and efficient production of the mine is ensuring the stability of the roadway.The present paper obtains typical failure characteristics and deformation and failure mechanisms of composite-roof roadway with a buried depth of 650 m at Zhaozhuang Coal Mine(Shanxi Province,China).On the basis of determining a reasonable cross-section shape of the roadway and according to the failure characteristics of the composite roof in different regions,the roof is divided into an unstable layer,metastable layer,and stable layer.The controlled unstable layer and metastable layer are regarded as a small structure while the stable layer is regarded as a large structure.A superimposed coupling support technology of large and small structures with a multi-level prestressed bearing arch formed by strong rebar bolts and highly prestressed cable bolts is put forward.The support technology provides good application results in the field.The study thus provides theoretical support and technical guidance for ground control under similar geological conditions. 展开更多
关键词 Deep mining composite roof Failure mechanism Ground control
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