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SUPERPlASTICITY OF A Ni-28.5Al-20.4Fe INTERMETAllIC AllOY

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Acta Metallurgica Sinica(English letters) 2000年第3期13卷 888-892页

作者： zhou, W.l. Guo, J.T. Chen, R.S. zhou, J.Y. Inst of Metal Research Chinese Acad of Sciences Shenyang China

Our previous investigation examined the superplastic behavior of an extruded Ni-28.5Al-20.4Fe alloy. Its tensile properties were determined at temperature from 1123 K to 1323 K and initial strain rates from 1.04×10-2s-1 to 1.04×10-4s-1. A maximum elongation of 233% was obtained at 1123 K and a strain rate of 5.2×10-4s-1. Furthermore, microstructural features, such as decrease in the average grain size after deformation at 850 °C and 980 °C, the presence of many dislocation-free grains adjacent to grains with a high dislocation density, indicate that dynamic recrystallization has occurred as an efficient accommodation mechanism. SEM examination of the fracture sample after superplastic deformation reveals many voids on the fracture surface. By correlating with the result of TEM observation, it is suggested that the superplastic deformation in this alloy should be controlled by a grain boundary sliding-based mechanism accommodated by the movement of dislocation and dynamic recrystallization.

关键词： Activation energy Aluminum alloys Intermetallics Iron alloys Microstructure Recrystallization (metallurgy) Superplasticity Tensile testing

Nanotechnology in retinal drug delivery

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International Journal of Ophthalmology(English edition) 2018年第6期11卷 1038-1044页

作者： Sibo Jiang Yesenia l Franco Yan zhou Jianjun Chen Department of Pharmaceutics University of Florida Department of Pharmaceutics University of Minnesota School of Pharmaceutical Sciences Guangdong Provincial Key Laboratory of New Drug Screening Southern Medical University

Retinal diseases, including age-related macular degeneration （AMD） and diabetic retinopathy （DR） are the leading causes of blindness in adults over the age of 50 years in the US. While most of those conditions do not have a cure, currently available treatment options attempt to prevent further vision loss. For many ophthalmic drugs, an efficient delivery system to provide maximum therapeutic efficacy and promote patient compliance remains an unmet medical need. An exploration of literature via PubMed spanning from 2007 to 2017 was conducted to identify studies that have evaluated nanotechnology as platforms for delivering therapeutic agents to the posterior segment of the eye where the retina is located. Until now, four routes that have been utilized for retinal drug delivery are the intravitreal, periocular, subretinal, and systemic routes. Intravitreal injections are now widely used in clinical practice due to their ability to directly target the back of the eye but are highly invasive procedures that may cause several complications, particularly with repeated uses over a short timespan. Nanotechnology shows great promise to revolutionize retinal drug delivery, offering many advantages such as a targeted delivery system towards the specific site of the retina as well as sustained delivery of therapeutic agents. In this review, specific eye anatomy and constraints on ocular drug administration are illustrated. Further, we list and highlight several examples of nanosystems, such as hydrogels, liposomes, dendrimers, and micelles, used via different drug delivery routes to treat various retinal diseases.

关键词： nanotechnology nanoparticle drug delivery retina age-related macular degeneration diabetic retinopathy

Comparison of gene expression between normalcolon mucosa and colon carcinoma by means of messenger RNA differential display

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World Journal of Gastroenterology 1999年第6期5卷 533-534页

作者： Wang l lu W Chen YG zhou XM Gu JR Shanghai Med Univ Dept Gastroenterol Huashan Hosp Shanghai 200040 Peoples R China Shanghai Canc Inst Natl Lab Oncogene & Related Genes Shanghai 200032 Peoples R China

INTRODUCTIONMessenger RNA differential display technique, developed by Dr. liang in 1992[1], is a powerful new tool for identifying and cloning differentially expressed genes in a certain type of cell line, tissue or a special developing stage. Using this method, large amounts of molecular biological information can be obtained easily and quickly. In our study, this technique was used to compare genes expressed differentially between normal colon mucosa and colon carcinomas, in order to understand the molecular biological basis of colon cancer.

关键词： colonic mucosa colonic neoplasms RNA, messenger gene expression

Development and Application of On-line Wind Power Risk Assessment System

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电力系统自动化 2012年第8期36卷 161-165页

作者： Su, Feng zhou, Xiaoxin Yu, Haiguo Xian, Wenjun lü, Ying Ren, lingyu Power System Department China Electric Power Research Institute Beijing 100192 China Qinghai Electric Power Dispatch Center Xining 810008 China

Because of the large-scale integration of wind power,the dynamic characteristics of power system have many uncertain *** on deterministic analysis methods,traditional on-line security assessment system cannot quantitatively estimate the actual operating conditions of the power system for only considering the most serious and credible ***,the risk theory is introduced into an on-line security assessment system and then an on-line risk assessment system for wind power is designed and implemented by combining with the dynamic security assessment *** on multiple data integration,the wind power disturbance probability is available and the security assessment of the power grid can obtain security indices in different *** operating risk index is an expectation of severity,computed by summing up all the products of the result probability and its *** results are reported to the dispatchers in on-line environment,while the comprehensive weak links are automatically provided to the power dispatching *** risk assessment system in operation can verify the reasonableness of the system.

关键词：安全评估系统风力发电系统风险理论应用开发定性分析方法动态安全评估电力调度中心

Effective Dielectric Properties of an Array of Multishell Carbon Nanotubes

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Chinese Physics letters 2001年第8期18卷 1129-1131页

作者： lÜ Wen-Gang WANG Rong-zhou DONG Jin-Ming National laboratory of Solid State Microstructures and Department of Physics Nanjing UniversityNanjing 210093

Using a photonic band calculation method,we calculate the effective dielectric function of an array of carbon nanotubes which have a simple equivalent isotropic dielectric *** results for the equivalent dielectric function and for the local graphite-like dielectric tensor are found to be almost the *** a fixed outer diameter of the nanotubes to be 10 nm and a fixed distance between them to be 10.3 nm,we investigate the effect of the hollow core and found that the ratio of the inner to the outer radii is approximately larger than *** taking a large ratio of 0.58,the theoretical results are improved greatly and can describe the experimental data very well.

关键词： dielectric outer function

Effect of strain,strain rate and temperature on workability of AZ80 wrought magnesium alloy

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中国有色金属学会会刊：英文版 2012年第S3期22卷 650-655页

作者： lü Wen-quan QUAN Guo-zheng YU Chun-tang ZHAO lei zhou Jie College of Materials Science and Engineering Chongqing University

The hot deformation behavior of AZ80 wrought magnesium alloy was studied in the temperature range of 523-673 K and the strain rate range of 0.01-10 s-1 using hot compression *** the flow stresses behavior,the processing maps were calculated and analyzed according to the dynamic materials *** stable,metastable and unstable regimes were *** optimum processing conditions were suggested as following:the DRX regions in Domain #1-0.25,Domain #2-0.25,Domain #1-0.45,Domain #2-0.45,Domain #3-0.45,Domain #1-0.65 and Domain #1-0.85,and the DRV regions in Domain #3-0.25 and Domain #*** each "safe" DRX domain,it is preferable to conduct hot working in the small region around efficiency peak *** strain has a great influence on the processing *** whole area of the "safe" domains increases with the increase of true strain from 0.25 to 0.65,while it decreases with the increase of true strain from 0.65 to *** results of kinetic analysis reveal that the values of apparent activation energy in all the domains are higher than that for self-diffusion in pure magnesium (135kJ/mol),and the deformation mechanism in all the domains is likely to be cross-slip.

关键词： AZ80 magnesium alloy strain rate kinetic analysis processing map flow behavior

Thermal hypersensitivity in a subset of irritable bowel syndrome patients

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World Journal of Gastroenterology 2009年第26期15卷 3254-3260页

作者： QiQi zhou Roger B Fillingim Joseph l Riley Ⅲ G Nicholas Verne Department of Medicine OhioState University Columbus Ohio 43210 United States College of Dentistry University of Florida Gainesville Florida 32610 United States North Florida/South Georgia Veteran Health System Gainesville Florida 32610 United States Research Service Cincinnati VAMCCincinnati Ohio 45220 United States

AIM： To characterize thermal hypersensitivity in patients with constipation- and diarrhea-predominant irritable bowel syndrome （IBS）. METHODS： Thermal pain sensitivity was tested among patients with diarrhea-predominant IBS （D-IBS） and constipation-predominant IBS （C-IBS） compared to healthy subjects. A total of 42 patients （29 female and 13 male; mean age 27.0 ＋ 6.4 years） with D-IBS; 24 patients （16 female and eight male; mean age 32.5 ：1：8.8 years） with C-IBS; and 52 control subjects （34 female and 18 male; mean age 27.3 ± 8.0 years） participated in the study. Thermal stimuli were delivered using a Medoc Thermal Sensory Analyzer with a 3 cm × 3 cm surface area. Heat pain threshold （HPTh） and heat pain tolerance （HPTo） were assessed on the left ventral forearm and left calf using an ascending method of limits. The Functional Bowel Disease Severity Index （FBDSI） was also obtained for all subjects. RESUlTS： Controls were less sensitive than C-IBS and D-IBS （both at P 〈 0.001） with no differences between C-IBS and D-IBS for HPTh and HPTo. Thermal hyperalgesia was present in both groups of IBS patients relative to controls, with IBS patients reporting significantly lower pain threshold and pain tolerance at both test sites. Cluster analysis revealed the presence of subgroups of IBS patients based on thermal hyperalgesia. One cluster （17% of the sample） showed a profile of heat pain sensitivity very similar to that of healthy controls; a second cluster （47% of the sample） showed moderate heat pain sensitivity; and a third cluster （36% of the sample） showed a very high degree of thermal hyperalgesia. CONClUSION： A subset of IBS patients had thermal hypersensitivity compared to controls, who reported significantly lower HPTh and HPTo. All IBS patients had a higher score on the FBDSI than controls. Interestingly, the subset of IBS patients with high thermal sensitivity （36%） had the highest FBDSI score compared to the other two groups of IBS patients.

关键词： Irritable bowel syndrome Visceral pain thermal hypersensitivity Heat pain threshold Heat pain tolerance

Disassociation of a one-dimensional cold molecule via quantum scattering

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Communications in Theoretical Physics 2023年第12期75卷 147-155页

作者： Wen-liang li Hai-Jing Song Tie-ling Song D l.zhou Institute of Physics Beijing National Laboratory for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China National Innovation Institute of Defense Technology AMSBeijing 100071China Department of Fundamental Science Space Engineering UniversityBeijing 101416China

Motivated by the recent experimental developments in ultracold molecules and atoms,we propose a simple theoretical model to address the disassociation,reflection,and transmission probability of a one-dimensional cold molecule via quantum ***,we show the Born approximation results in the weak interaction ***,by employing the lippmann-Schwinger equation,we give the numerical solution and investigate the disassociation’s dependence on the injection momentum and the interaction *** find that the maximum disassociation rate has a limit when increasing the interaction strengths and injection *** expect that our model can be realized in experiments in the near future.

关键词： cold molecule quantum scattering disassociation rate

A　k－ε－PDF　Two－Phase　Turbulence　Model　for　Simulating　Sudden－Expansion　Particle－laden　Flows

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Journal of Thermal Science 1996年第1期5卷 34-38页

作者： Y.li l.X.zhou DepartmentofEngineeringMechanics TsinghuaUniversityBeijingChina DepartmentofEngineeringMechanics Ts

A k - ε-PDF model based on statistical theory for turbulent gas-particle flows is proposed,and a numerical procedure combining the finite difference and finite fluctuating-velocity -group methods is *** obtained statistically averaged equations have the same form as those obtained by using the Reynolds *** the k -ε-PDF model (PDF particle turbulence model combined with the k - ε gas turbulence model),many terms,such as the diffusion term in particle Reynolds Stress equations,can be accurately calculated for verifying the second-moment-closure *** k - ε- PDF model is used to simulate sudden-expansion particle-laded *** of the predictions using both k -ε-PDF and the k - ε- kp models with experimental results shows that the k - ε-PDF model give more reasonable non-isotropic features of particle turbulence.

关键词： turbulent gas-particle flows statistical theory turbulence models nonisotropic turbulence.