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Transitional Process of Ploy(N-isopropylacrylamide) in Deuterated Solution
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作者 Shao-hua Zhang Yang Chen +1 位作者 Heng Li Yu-xiang Weng 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第5期447-452,I0001,共7页
The fast phase-transitional process of ploy(N-isopropylacrylamide) (PNIPAM) in deuterated solution was studied by laser induced temperature jump technique combined with time-resolved mid-infrared absorbance differ... The fast phase-transitional process of ploy(N-isopropylacrylamide) (PNIPAM) in deuterated solution was studied by laser induced temperature jump technique combined with time-resolved mid-infrared absorbance difference spectroscopy on nanosecond level. The multi-peaks of amide I'band of PNIPAM among the energy range of 1565-1700 cm^-1 was experimentally resolved to three groups (i, ii, iii) for the first time, while the distinct threestage procedure in the phase transitional process of long-chain PNIPAM was observed firstly too. Furthermore, proper assignments were also made for the three group peaks in amide I'band and the three steps in the kinetics process of long-chain PNIPAM. 展开更多
关键词 Poly(N-isopropylacrylamide) Laser induced temperature jump Kinetic Transient mid-infrared absorbance difference spectroscopy MULTISTAGE transitional process
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Phase Transition in Recovery Process of Complex Networks
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作者 肖文 杨超 +1 位作者 羊亚平 陈宇光 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第5期132-136,共5页
The dynamic characteristic of complex network failure and recovery is one of the main research topics in complex networks. Real world systems such as traffic jams and Internet recovery could be described by the comple... The dynamic characteristic of complex network failure and recovery is one of the main research topics in complex networks. Real world systems such as traffic jams and Internet recovery could be described by the complex network theory. We propose a model to study the recovery process in complex networks. Two different recovery mechanisms are considered in three kinds of networks: external recovery and internal recovery. By simulating the process of the nodes recovery in networks, it is found that the system exhibits the feature of first-order phase transition only when the external recovery is considered. Internal recovery cannot induce such a kind of transitions. As external recovery and internal recovery coexist on networks, the systems will retain the most efficient part of external recovery and internal recovery. Meanwhile, a hysteresis could be observed when increasing or decreasing the failure probability. Finally, a largest degree node protection strategy is proposed for improving the robustness of networks. 展开更多
关键词 NET Phase Transition in Recovery process of Complex Networks ERN HNA SFN LNA
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Influence of Different Transition Modes on the Performances of a Hydraulic Turbine
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作者 Fengxia Shi Yucai Tang +2 位作者 Dedong Ma Xiangyun Shi Guangbiao Zhao 《Fluid Dynamics & Materials Processing》 EI 2023年第10期2481-2497,共17页
In order to analyze the response of a hydraulic turbine to a variation in the operating conditions,different laws of variation in time of the massflow rate have been considered.After validating the overall numerical fr... In order to analyze the response of a hydraulic turbine to a variation in the operating conditions,different laws of variation in time of the massflow rate have been considered.After validating the overall numerical framework through comparison with relevant experiments,the performances of the considered turbine have been analyzed from afluid-dynamic point of view.The results show that different time profiles of the massflow rate(in this work,for simplicity,referred to as“transition functions”)have a varying influence on the transient behavior of the turbine.When a quadratic function is considered for the case of largeflow,the transient head and torque increase gradually with time,thefluctuation amplitude of the transient hydraulic efficiency at the main frequency is the largest,and thefluctuation amplitude of the radial force is the smallest.For the smallflow case,the time profile with exponential nature leads to the best results.The transient head and torque decrease gradually with time,the pulsation amplitude of the transient hydraulic efficiency is the largest at the main frequency,and the pulsation amplitude of the radial force is the smallest. 展开更多
关键词 Transition functions hydraulic turbine transition process radial resultant force
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Liquid crystal droplets formation and stabilization during phase transition process
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作者 Xia Meng Jiayao Ye +5 位作者 Ao Li Xudong Zhu Zhaoyan Yang Lei Wang Bingxiang Li Yanqing Lu 《Chinese Physics B》 SCIE EI CAS 2024年第11期106-111,共6页
The study of phase transition processes in liquid crystals(LCs)remains challenging.Most thermotropic LCs exhibit a narrow temperature range and a rapid phase transition from the isotropic(ISO)to the nematic(N)phase,wh... The study of phase transition processes in liquid crystals(LCs)remains challenging.Most thermotropic LCs exhibit a narrow temperature range and a rapid phase transition from the isotropic(ISO)to the nematic(N)phase,which make it difficult to capture and manipulate the phase transition process.In this study,we observed the evolution of small droplets during the ISO–N phase transition in ferroelectric nematic(NF)LC RM734.After doping with metal nanoparticles(NPs),the temperature range of the phase transition broadened,and the droplets formed during the phase transition remained stable,with their diameter increasing linearly with temperature.In addition,droplets doped with NPs can be well controlled by an external electric field.This discovery not only aids in understanding the fundamental mechanisms of LC phase transitions but also provides a simple alternative method for preparing droplets,which is potentially valuable for applications in optoelectronic devices and sensors. 展开更多
关键词 liquid crystal droplets phase transition process metal nanoparticles
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Emotional Gait Generation for a Humanoid Robot 被引量:1
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作者 Lun Xie Zhi-Liang Wang Wei Wang Guo-Chen Yu School of Information Engineering, University of Science and Technology Beijing, Beijing 100083, PRC 《International Journal of Automation and computing》 EI 2010年第1期64-69,共6页
In this paper, an emotional mathematical model and affective state probability description space of a humanoid robot are set up on the basis of psycho-dynamics' psychological energy and affective energy conservation ... In this paper, an emotional mathematical model and affective state probability description space of a humanoid robot are set up on the basis of psycho-dynamics' psychological energy and affective energy conservation law. The emotional state transferring process and hidden Markov chain algorithm of stimulating transition process are then studied. The simulation results show that the mathematical model is applicable to the authentic affective state change rule of human beings. Finally, the gait generation experiment results of control signal and electric current tracking wave-form are presented to demonstrate the validity of the proposed mathematical model. 展开更多
关键词 Emotional mathematical model humanoid robot hidden Markov chain stimulating transition process gait generation.
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Improving the process forming limit considering forming defects in the transitional region in local loading forming of Ti-alloy rib-web components 被引量:2
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作者 Pengfei GAO Xiaodi LI +2 位作者 He YANG Xiaoguang FAN Zhenni LEI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第3期1270-1280,共11页
The isothermal local loading forming technology provides a feasible way to form Ti-alloy large-scale rib-web components in aerospace and aviation fields.However,the local loading process forming limit is restricted by... The isothermal local loading forming technology provides a feasible way to form Ti-alloy large-scale rib-web components in aerospace and aviation fields.However,the local loading process forming limit is restricted by forming defects in the transitional region.In this work,the feasibility of controlling forming defects and improving the process forming limit by adjusting die parameters is explored through finite element(FE) simulation.It is found that the common cavum and folding defects in the transitional region are significantly influenced by the fillet radii of left rib and middle rib,respectively.The cavum and folding defects can be effectively controlled by increasing the fillet radii of left rib and middle rib,respectively.The process forming limits considering forming defects in the transitional region are determined by the stepwise searching method under various die parameters.Moreover,the relationship between the process forming limit and die parameters is developed through the response surface methodology(RSM).The developed RSM models suggest that increasing the fillet radii of left and middle ribs is effective to improve the process forming limit during local loading forming of rib-web components.The results will provide technical basis for the design of die parameters and the reduction amount,which is of great importance to control forming defects and improve the process forming limit in local loading forming of Ti-alloy large-scale rib-web components. 展开更多
关键词 Defect Large-scale rib-web component Local loading forming process forming limit transitional region
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Mechanical Behavior of Bistable Bump Surface for Morphing Inlet
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作者 张平 周丽 程文杰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第6期610-622,共13页
There exists inlet-engine match conflict between high and low speeds for a non-adjustable bump inlet.A scheme of using a bistable bump surface at the throat region of the inlet is proposed to adjust the throat area.Th... There exists inlet-engine match conflict between high and low speeds for a non-adjustable bump inlet.A scheme of using a bistable bump surface at the throat region of the inlet is proposed to adjust the throat area.The FEM model of the bistable surface is established with hinged constraint,and the bistability condition and structural transition process are investigated in detail.Moreover,the effects of loading method,loading position and structural parameters on critical driving force,input energy and structural strain are studied.Finally,the influences of an elastic boundary condition on the structural bistability are discussed.The results show that the bistability of the adjustable bump surface requires a certain boundary constraint and geometric parameter combination,and that there are local and overall snap-through phenomena during transition which are related to the loading position and structural parameters.Therefore,suitable loading position and structural material could reduce input energy and meet the demand of structural strain. 展开更多
关键词 bistable structure inlet-engine match bump surface morphing inlet transition process
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Adaptive SPC monitoring scheme for DOE-based APC
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作者 Ye Liang Pan Ershun Xi Lifeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第2期329-336,共8页
Automatic process control (APC) based on design of experiment (DOE) is a cost-efficient approach for variation reduction. The process changes both in mean and variance owing to online parameter adjustment make it hard... Automatic process control (APC) based on design of experiment (DOE) is a cost-efficient approach for variation reduction. The process changes both in mean and variance owing to online parameter adjustment make it hard to apply traditional SPC charts in such DOE-based APC applied process. An adaptive SPC scheme is developed, which can better track the process transitions and achieve the possible SPC run cost reduction when the process is stable. The control law of SPC parameters is designed by fully utilizing the estimation properties of the process model instead of traditionally using the data collected from the production line. An example is provided to illustrate the proposed adaptive SPC design approach. 展开更多
关键词 automatic process control statistical process control robust parameter design process transitions.
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APPLICATION OF AN OBJECTIVE DISCRIMINATING METHOD IN THE EVOLUTION OF TROPICAL CYCLONE“HAIMA”DURING EXTRATROPICAL TRANSITION
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作者 张迎新 张守保 王福侠 《Journal of Tropical Meteorology》 SCIE 2008年第2期149-152,共4页
An objective method for discriminating the process of extratropical transition (ET) in tropical cyclones is introduced. With this method, the gridpoint output data of NWP are used to calculate three parameters: sto... An objective method for discriminating the process of extratropical transition (ET) in tropical cyclones is introduced. With this method, the gridpoint output data of NWP are used to calculate three parameters: storm-relative thickness symmetry (B), low-level (-VL^L ) and upper-level thermal wind (-VT^U ). This objective method is easy to calculate and convenient for operational use. To verify the method, this paper uses the NCEP reanalysis data to identify the evolution of ET for "Haima", a tropical storm (0421) that affected the eastern part of China in 2004. The result shows that the three parameters defined with the objective method are good indicators of the ET process. 展开更多
关键词 tropical cyclone process of extratropical transition parameter of thermal asymmetry (B) thermal wind
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Factors influencing female patients’ recovery after their first myocardial infarction as experienced by cardiac rehabilitation nurses
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作者 Inger Wieslander Jan Martensson +1 位作者 Bengt Fridlund Petra Svedberg 《Open Journal of Nursing》 2013年第2期230-240,共11页
Background: In the developed part of the world, coronary heart disease is the major cause of death and is one of the leading causes of disease burden. In Sweden, more than 30,000 people per year are affected by myocar... Background: In the developed part of the world, coronary heart disease is the major cause of death and is one of the leading causes of disease burden. In Sweden, more than 30,000 people per year are affected by myocardial infarction and out of these approximately 40% are women. Nearly 70% of the women survive and after a myocardial infarction a recovery process follows. Today’s health care focuses more on treatment, symptoms and risk factors than on the individuals’ perceptions of the recovery process. Aim: To explore cardiac rehabilitation nurses’ experiences of factors influencing female patients’ recovery after their first myocardial infarction. Methods: Twenty cardiac rehabilitation nurses were interviewed. The study was conducted using qualitative content analysis. Results: The cardiac rehabilitation nurses experienced that women’s recovery after a first myocardial infarction was influenced whether they had a supportive context, their ability to cope with the stresses of life, if they wanted to be involved in their own personal care and how they related to themselves. Conclusions: Women’s recovery after a myocardial infarction was influenced by factors related to surroundings as well as own individual factors. The underlying meaning of women’s recovery can be described as the transition process of a recovery to health. Our findings suggest that a focus on person-centered nursing would be beneficial in order to promote the every woman’s personal and unique recovery after a myocardial infarction. Finally, the cardiac rehabilitation nurses’ experiences of factors influencing male patients’ recovery after their first myocardial infarction should be important to investigate. 展开更多
关键词 Cardiac Rehabilitation Nurses Myocardial Infarction RECOVERY Transition process WOMEN
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Wide-range color-tunable afterglow emission by the modulation of triplet exciton transition processes based on buckybowl structure
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作者 Yongfeng Zhang Chenchen Xiong +10 位作者 Wenbo Wang Wenbo Dai Yue Ren Junming Xia Gengchen Li Jianbing Shi Bin Tong Xiaoyan Zheng Xiangfeng Shao Zhengxu Cai Yuping Dong 《Aggregate》 2023年第4期93-99,共7页
Buckybowl structures as non-uniform electrostatic potential distributions of poly-cyclic aromatic materials show a unique photoelectric performance.In this work,OTC was utilized for dynamic modulation of triplet excit... Buckybowl structures as non-uniform electrostatic potential distributions of poly-cyclic aromatic materials show a unique photoelectric performance.In this work,OTC was utilized for dynamic modulation of triplet exciton transition processes.Five host molecules with different functional units were selected,thus providing dif-ferent intermolecular interactions in the host/guest systems.Therefore,the delayed emissions were regulated from 536 to 624 nm via the tuning of the triplet exciton transition processes of OTC in different hosts.Experimental data and theoretical calculations revealed that the varied triplet transition behaviors resulted from the competition between the intersystem crossing(ISC)process of OTC-monomer and the reverse intersystem crossing(RISC)process of OTC-aggregates.This work proves the superior structure of buckybowl-based luminophore for controlling triplet exciton transition processes and supplies a new perspective for persistent afterglow luminophore design. 展开更多
关键词 buckybowl structure dynamic modulation host/guest doping systems room temperature phosphores-cence triplet exciton transition processes
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Experimental Study on Heat Storage Properties Comparison of Paraffin/Metal Foams Phase Change Material Composites 被引量:1
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作者 Waqar AHMED Abid HUSSAIN +2 位作者 Hanzla SHAHID Imran ALI Hafiz Muhammad ALI 《Journal of Thermal Science》 SCIE EI CAS CSCD 2024年第2期469-478,共10页
Heat storage properties of phase change materials(PCMs) are essential characteristics that perform a key role in thermal heat energy storage systems.The thermal properties of PCMs can be improved by developing metal f... Heat storage properties of phase change materials(PCMs) are essential characteristics that perform a key role in thermal heat energy storage systems.The thermal properties of PCMs can be improved by developing metal foam/PCM composites.The addition of metal foam in PCMs has a significant effect on the thermal characteristics of PCMs.In this paper,the heat storage properties of two different metal foam/PCM composites were experimentally examined.The behavior of paraffin in metal foam(copper and iron-nickel)/paraffin composites concerning pure paraffin at a constant heat flux of 1000 W/m^(2) in three directions simultaneously(x,y,and z) was studied.Paraffin was infiltrated into copper and iron-nickel foams to develop composite materials which resulted in enhancing the thermal conductivity of the paraffin.A comparative analysis is made on the heat storage properties of paraffin in copper and iron-nickel foams/paraffin composites.Inner temperature distribution during the phase transition process is experimentally evaluated.This comparison indicates that temperature uniformity in copper foam/paraffin composite is better than in iron-nickel foam/paraffin composite and pure paraffin at the same heat flux.Experimental results show that at heat flux of 1000 W/m^(2),the heat storage time for copper foam/paraffin composite is 20.63% of that of iron-nickel foam/paraffin composite. 展开更多
关键词 heat storage capacity paraffin/metal foam composite temperature uniformity heat storage rate phase transition process
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GATE REGULATION SPEED AND TRANSITION PROCESS OF UNSTEADY FLOW IN CHANNEL 被引量:4
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作者 TAN Guang-ming DING Zhi-liang WANG Chang-de YAO Xiong 《Journal of Hydrodynamics》 SCIE EI CSCD 2008年第2期231-238,共8页
The operation methods of channel and the speed of gate regulation have great influence on the transformation of flow in water conveyance channels. Based on characteristics method, a 1-D unsteady flow numerical model f... The operation methods of channel and the speed of gate regulation have great influence on the transformation of flow in water conveyance channels. Based on characteristics method, a 1-D unsteady flow numerical model for gate regulation was established in this study. The process of water flow was simulated under different boundary conditions. The influence of gate regulation speed and channel operation methods on flow transition process was analyzed. The numerical results show that under the same conditions, with increasing regulation speed of the gate, the change rates of discharge and water level increase, while the response time of channel becomes shorter, and ultimately the discharge and water level will transit to the same equilibrium states. Moreover, the flow is easier to reach stable state, if the water level in front of the sluice is kept constant, instead of,behind the sluice. This study will be important to the scheme design of automatic operation control in water conveyance channels. 展开更多
关键词 check gate regulation speed unsteady flow transition process numerical simulation
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PROCESS OF TRANSITION BETWEEN COLD AND WARM PERIODS AND ITS PREDICTION
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作者 魏凤英 曹鸿兴 王丽萍 《Acta meteorologica Sinica》 SCIE 2003年第2期190-204,共15页
The oscillation of multi-time scales and the process of transition between cold and warm periods over most parts of China and its 6 regions (the Northeast,North China,Changjiang River Valley,South China,the Southwest,... The oscillation of multi-time scales and the process of transition between cold and warm periods over most parts of China and its 6 regions (the Northeast,North China,Changjiang River Valley,South China,the Southwest,the Northwest) were analyzed with wavelet transformation and by computing the variances of the wavelet components for the temperature grade series during January 191I to February 2001,The prediction model for cold and warm periods has been developed and the trend of cold and warm change in the coming 10 years is predicted.The results show that the oscillation with periods of around 30-40 years was the strongest in the last 100 years and the 3-year oscillation in both winter and summer was also stronger,especially in winter. The transition time of cold and warm periods in terms of winter mean did not coincide with that of annual mean,but the difference between summer mean and annual mean is less.The processes of transition of 6 regions are somewhat different,their main characteristics are that the beginning year of significant warming for 1980s to 1990s was very different for the southern and the northern part of China.It is found that the stronger oscillation with 3-year period causes cooling in Northeast China in recent several winters.The experimental predictions show that the models used in the paper can project the major transition between high and low temperature periods. 展开更多
关键词 trend of coldness and warmness process of transition inter-annual oscillations inter-decadal oscillations
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Calculation of vibrational energy transition rates in acoustic relaxation processes for excitable gas molecules
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作者 ZHANG Kesheng ZHANG Xiangqun +2 位作者 TANG Wenyong XIAO Yingqun JIANG Xueqin 《Chinese Journal of Acoustics》 CSCD 2018年第2期202-218,共17页
To research the correlation between vibrational energy transition rates and acoustic relaxation processes in excitable gases, the vibrational relaxation theory provided by Tanczos [J. Chem. Phy3. 25, 439 (1956)] is ... To research the correlation between vibrational energy transition rates and acoustic relaxation processes in excitable gases, the vibrational relaxation theory provided by Tanczos [J. Chem. Phy3. 25, 439 (1956)] is applied to calculate the energy transition rates of Vibrational- Vibrational (V-V) and Vibrational-Translational (V-T) energy transfer in gas mixtures. The results of calculation for the multi-relaxation processes in various gas mixtures, consisting of carbon dioxide, methane, chlorine, nitrogen, and oxygen at room temperature, demonstrate that the acoustic energy stagnated in every vibrational mode is coupled with each other through V-V energy exchanges. The vibrational excitation energy will relax through the V-T de-excitation path of the lowest mode because of its fastest V-T transition rate, resulting in that only one absorption peak can be measured for most of excitable gas mixtures. Thus, an effective model is provided to analyze how the vibrational energy transition rates affect the characteristics of acoustic relaxation processes and acoustic propagation in excitable gas mixtures. 展开更多
关键词 Calculation of vibrational energy transition rates in acoustic relaxation processes for excitable gas molecules
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THE POINT PROCESS OF STATETRANSITIONS IN AREGULAR MARKOV CHAIN
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作者 史定华 郭进利 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 1998年第4期374-380,共7页
In this paper, we study the point process of state transitions in a regular Markov chain.Under a weaker condition, we prove that the point process is a 1-memory self-exciting point process and again obtain four useful... In this paper, we study the point process of state transitions in a regular Markov chain.Under a weaker condition, we prove that the point process is a 1-memory self-exciting point process and again obtain four useful formulas of the transition frequency, the absorbing distribution,the renewal distribution and the entering probability. As an applicstion, using these formulas we derive the LS transform of the busy period for the M/M/∞ queue. 展开更多
关键词 point process regular Markov chain state transition counting process transition frequency formula queueing theory
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Visualizing phase transition of upper critical solution temperature (UCST) polymers with AIE 被引量:1
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作者 Yong-Guang Jia Kai-Feng Chen +10 位作者 Meng Gao Sa Liu Jin Wang Xiaohui Chen Lin Wang Yunhua Chen Wenjing Song Huatang Zhang Li Ren Xiao-Xia Zhu Ben Zhong Tang 《Science China Chemistry》 SCIE EI CAS CSCD 2021年第3期403-407,共5页
The stimuli-responsive polymers with upper critical solution temperatures(UCST) are highly attractive for drug delivery applications. However, the phase transition process of UCST polymer is usually characterized by t... The stimuli-responsive polymers with upper critical solution temperatures(UCST) are highly attractive for drug delivery applications. However, the phase transition process of UCST polymer is usually characterized by turbidity measurement and electron microscopy, which are significantly restricted by low sensitivity and static observation. In contrary, the fluorescence technique has significant advantages in terms of high sensitivity, easy operation, and dynamic observation. However, the conventional fluorophores suffer from the drawbacks of aggregation-caused quenching(ACQ) after being encapsulated by UCST polymers, which are not suitable for direct visualization of the phase transition process. To tackle this challenge, we herein developed a series of UCST polymers based on polyacrylamides decorated with bile acid and aggregation-induced emission(AIE)-active tetraphenylethene(TPE) groups, which can be used for direct fluorescence monitoring of the phase transition process. Moreover, the AIE-active UCST polymers can serve as drug carriers, which can not only monitor the drug release process under thermal stimuli, but also verify the drug release by fluorescence recovery after thermal stimuli. It is expected that the AIE-active UCST polymers with self-monitoring ability are promising for biomedical applications. 展开更多
关键词 upper critical solution temperatures aggregation-induced emission phase transition process drug release monitoring bile acid
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Technical Progress and the Diffusion of Innovations: Classical and Schumpeterian Perspectives1
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作者 Heinz D. Kurz 《Frontiers of Economics in China-Selected Publications from Chinese Universities》 2017年第3期418-449,共32页
The paper discusses the diffusion of new technologies from the perspective of the classical economists and Schumpeter. After a comparison of the pre- and post-technical change long-period positions of the economy, we ... The paper discusses the diffusion of new technologies from the perspective of the classical economists and Schumpeter. After a comparison of the pre- and post-technical change long-period positions of the economy, we illustrate the process of transition between the two in terms of a two-sector model Next, we turn to a system with joint production. The fact that some products may be "bads" that need to be disposed of leads to a study of systems of production-cure-disposal. Finally, we investigate the selection pressure innovations exert on incumbent firms. An important message is that technical change cannot generally be studied within a partial framework of the analysis. 展开更多
关键词 classical economists creative destruction DIFFUSION disposalprocesses INNOVATION joint production SCHUMPETER Joseph A. selectionpressure technical change transition processes
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