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Journal of Thermal Science 2004年第2期13卷 155-162页

作者： Sui Lin zheng jiang Department of Mechanical and Industrial Engineering Concordia University Montreal Canada Flomerics Inc. Southborough USA

The purpose of the paper is to establish a theory of the constant heat flux ratio across the frozen layer based on the dimensional analysis of the system equations describing the freezing processes. An analytical model is then developed, utilizing this theory, for solving the planar, cylindrical and spherical freezing problems with both inward and outward freezing. As there is no exact solution available for the cylindrical and spherical freezing processes, the temperature distribution in the planar solidification obtained from the model is compared with the exact solution. They are in excellent agreement. For the cylindrical and spherical freezing, the complete inward solidification times calculated by the model are compared with those obtained from references. The results are in good agreement. The great advantage of the proposed model is its simplicity and is sufficiently accurate for most practical

关键词： analytical planar cylindrical spherical solidification theory constant heat flux ratio.

Method for Improving Transverse Wall Thickness Precision of Seamless Steel Tube Based on Tube Rotation

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Journal of Iron and Steel Research International 2015年第10期22卷 924-930页

作者： Yong-zheng jiang Hua-ping TANG State Key Laboratory of High Performance Complex Manufacturing Central South University

The tube rotation method （TRM） refers to the rotational movement of steel tube about its axis as well as translation in rolling direction in stretch reducing rolling process. The influence of the TRM on transverse wall thickness precision of seamless steel tube was studied. Thickness distribution of the TRM was obtained by superimposing the thickened amount of single pass rolling. Results show that the TRM can effectively improve the evenness of thickness distribution. In order to analyze the influence mechanism of the TRM, the finite element method was adopted to simulate the thickness distribution in stretch reduction process. Results show that the TRM changes the roundtrip flow between two fix places of conventional stretch reducing and inhibits the directional accumulation of metal. In addition, the TRM has a correction effect on thickness cusp. All these advantages of the TRM help to improve the transverse wall thickness precision of seamless steel tube.

关键词： seamless tube stretch reducing transverse unevenness tube rotation method

Photo-degradation of Acid-red 3B dye catalyzed by TiO_2 nanotubes

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Journal of Environmental Sciences 2006年第4期18卷 783-787页

作者： jiang Fang zheng Shou-rong zheng zheng XU Zhao-yi WANG Yan-jin State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China

TiO2 nanotube precursor was synthesized by the hydrothermal reaction of TiO2 powders with NaOH solution and the properties of the nanotube materials were tuned using different post-treatments. Transmission electron microscopic （TEM） observation revealed that the nanotube could be obtained by either a direct rinse with acid solution or rinse with distilled water followed by acid solution. The results of X-ray diffraction （XRD） and inductively coupled plasma （ICP） analysis indicated that the nanotube material was composed of H2Ti2O5·H2O. In addition, the photocatalytic activities of the resulting catalysts were found to be strongly dependent on the post-treatment. The results of the photocatalytic reaction showed that the degradation of Acid-red 3B dye fitted pseudo-zero-order kinetics and TiO2 nanotube prepared under direct rinse with acid solution exhibited a higher catalytic efficiency compared to other catalysts.

关键词： TiO2 nanotube Acid-red 3B photocatalysis hydrothermal reaction

Galvanic Effect Between Galvanized Steel and Carbon Fiber Reinforced Polymers

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Acta Metallurgica Sinica(English Letters) 2017年第4期30卷 342-351页

作者： Chi Zhang Da-jiang zheng Guang-Ling Song Center for Marine Materials Corrosion and Protection State Key Laboratory of Physical Chemistry of Solid SurfaceCollege of MaterialsXiamen University School of Mechanical and Mining Engineering The University of Queensland

The galvanic corrosion behavior of carbon fiber reinforced polymers （CFRPs） GM-CFRP and Tepex-CFRP in contact with a Zn-coated DP590 steel in solution containing 0.9 wt% NaCl＋ 0.1 wt% CaCl2 ＋ 0.075 wt% NaHCO3 was investigated. The results showed that the GM-CFRP/steel couple was initially more resistant to galvanic corrosion, but its galvanic corrosion activity gradually became higher than the Tepex-CFRP/steel couple. The different galvanic behaviors of these two couples were discussed based on the electrochemical performance of GM-CFRP, Tepex-CFRP and DP590 coupons in the testing solution.

关键词： Carbon fiber reinforced polymer (CFRP) Composite Carbon fiber Steel Galvanic effect

Retreatment of a patient who presented with synchronous multiple primary colorectal carcinoma: report of a case

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Chinese Journal of Cancer Research 2013年第4期25卷 482-485页

作者： zheng jiang Shan Muhammad Xishan Wang Colorectal Cancer Institute of the Heilongjiang Academy of Medical Sciences Department of Colorectal Cancer Surgery The 2nd Affiliated HospitalHarbin Medical University

It is well known that one-stage resection of synchronous multiple primary colorectal carcinoma is an ideal choice if the patient＇s physical condition is not bad. Detailed examination of the whole intestinal tract is very important for patients with colorectal cancer, which could prevent patients from receiving repeat treatment to a great extent. We present a case report of a patient with synchronous primary colorectal cancer. Because pre-or intra-operative examination is not sufficient at his first consultation, the patient had undergone multiple operations after receiving chemotherapy, radiotherapy and intestinal stent insertion, which results in peritoneal adhesions formation. The preoperative placement of prophylactic ureteral catheters facilitated recognition of ureters in operation that assure the prevention of ureteral injuries. If not aware of the importance of detailed preoperative examination and standardized treatment can lead to wrong treatment as in this case. Prophylactic ureteral catheters might assist in their immediate recognition.

关键词： Synchronous multiple primary colorectal carcinoma repeat operation prophylactic ureteral catheters

Inter- and intra-hemispheric EEG coherence in patients with mild cognitive impairment at rest and during working memory task

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第5期7卷 357-364页

作者： jiang zheng-yan zheng Lei-lei Department of Psychiatry the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China

Objective： To assess functional relationship by calculating inter- and intra-hemispheric electroencephalography （EEG） coherence at rest and during a working memory task of patients with mild cognitive impairment （MCI）. Methods： The sample consisted of 69 subjects： 35 patients （n = 17 males, n = 18 females; 52-71 years old） and 34 normal controls （n = 17 males, n = 17 females; 51 -63 years old）. Mini-mental state examination （MMSE） of two groups revealed that the scores of MCI patients did not differ significantly from those of normal controls （P〉0.05）. In EEG recording, subjects were performed at rest and during working memory task. EEG signals from F3-F4, C3-C4, P3-P4, T5-T6 and O1-O2 electrode pairs are resulted from the inter-hemispheric action, and EEG signals from F3-C3, F4-C4, C3-P3, C4-P4, P3-O1, P4-O2, T5-C3, T6-C4, T5-P3 and T6-P4 electrode pairs are resulted from the intra-hemispheric action for delta （1.0-3.5 Hz）, theta （4.0-7.5 Hz）, alpha-1 （8.0-10.0 Hz）, alpha-2 （10.5-13.0 Hz）, beta-1 （13.5-18.0 Hz） and beta-2 （18.5-30.0 Hz） frequency bands. The influence of inter- and intra-hemispheric coherence on EEG activity with eyes closed was examined using fast Fourier transformation from the 16 sampled channels. Results： During working memory tasks, the inter- and intra-hemispheric EEG coherences in all bands were significantly higher in the MCI group in comparison with those in the control group （P〈0.05）. However, there was no significant difference in inter- and intra-hemispheric EEG coherences between two groups at rest. Conclusion： Experimental results comprise evidence that MCI patients have higher degree of functional connectivity between hemispheres and in hemispheres during working condition, It suggests that MCI may be associated with compensatory processes during working memory tasks between hemispheres and in hemispheres. Moreover, failure of normal cortical connections may exist in MCI patients.

关键词： Mild cognitive impairment (MCI) EEG Coherence Working memory Cortical connectivity

Analysis of working behavior of Jinping-I Arch Dam during initial impoundment

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Water Science and Engineering 2016年第3期9卷 240-248页

作者： Shi-yong Wu Wei Cao jiang zheng Yalong River Hydropower Development Company Ltd.

To study the stress, deformation, and seepage pressure during the initial impoundment of the Jinping-I Arch Dam, monitoring analysis and numerical calculation were used in a dam behavior analysis that focused on the working behavior of the dam during the late period of the initial impoundment up to the end of November 2014. The numerical calculation was performed based on feedback analysis of the deformation and stress of the arch dam through inversion of the elastic moduli(E) of the dam body and foundation, using a three-dimensional finite element model for the linear elastic material of the arch dam. The main monitoring indices presented insignificant changes in the late period of the initial impoundment, and the results of feedback analysis were consistent with monitoring results. Analysis results also show that the deformations of the dam body and dam foundation were within the design range; the dam stress distributions were normal, with values lower than the design control criteria; and the seepage flows through the dam body and dam foundation were lower than the design drainage capacity of the deep-well pump house, demonstrating that the Jinping-I Arch Dam was in good working condition, and the initial impoundment had been successfully completed. The results of the working behavior analysis of the Jinping-I hydropower project during the initial impoundment can provide references for safe operation of similar projects.

关键词： Dam safety monitoring Working behavior Elastic modulus Dam impoundment Jinping-I hydropower project

Quick-scanning X-ray absorption fine structure beamline at SSRF

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Nuclear Science and Techniques 2024年第6期35卷 1-13页

作者： Yu Chen Qian Gao zheng jiang Jiong Li Shuo Zhang Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China

The layout and characteristics of the hard X-ray spectroscopy beamline(BL11B)at the Shanghai synchrotron radiation facility are described ***11B is a bending-magnet beamline dedicated to conventional and millisecond-scale quick-scanning X-ray absorption fine *** is equipped with a cylindrical collimating mirror,a double-crystal monochromator comprising Si(111)and Si(311),a channel-cut quick-scanning Si(111)monochromator,a toroidal focusing mirror,and a high harmonics rejection *** can provide 5-30 keV of X-rays with a photon flux of~5×10^(11)photons/s and an energy resolution of~1.31×10^(-4)at 10 *** performance of the beamline can satisfy the demands of users in the fields of catalysis,materials,and environmental *** paper presents an overview of the beamline design and a detailed description of its performance and capabilities.

关键词： Bending magnet beamline X-ray absorption fine structure Quick-scanning XAFS In situ Synchrotron radiation

Observer‑Based Resilient Control of CACC Vehicle Platoon Against DoS Attack

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Automotive Innovation 2023年第2期6卷 176-189页

作者： Xiao Tan Bin Liu Jingzhao Chen zheng jiang Engineering Research Center for Metallurgical Automation and Measurement Technology Ministry of EducationWuhan University of Science and TechnologyWuhan 430081China School of Information Science and Engineering Wuhan University of Science and TechnologyWuhan 430081China

Cooperative adaptive cruise control(CACC)is an important technology for improving road utilization and energy efficiency in the automotive *** CACC systems,connected vehicles can receive information from adjacent ones through com-munication ***,the networks are vulnerable to cyber-attacks,so the states of vehicles cannot be received promptly and *** paper studies the security resilience control for a CACC system subject to denial of service(DoS)*** core of the proposed resilient control strategy is to estimate the delay caused by DoS attack and then compensate for it in the ***,a CACC system is modeled by considering the impacts of DoS attack on the transmitted ***,a high-gain observer is presented to estimate the vehicle states including the time *** conver-gence of the observer is proved in a theorem based on the Lyapunov stability theory,and the high-gain-velocity observer is modified so that the estimation error of the velocity can converge to zero in a finite time.A resilient controller is designed by proposing a time delay compensation algorithm to mitigate the impacts of DoS *** effectiveness of the estimation and control methods is illustrated by a ten-vehicle simulation system operating at the FTP75 driving cycle *** the relative estimation errors are less than 6%.

关键词： Connected vehicle Resilient control DoS attack High-gain observer Time delay compensation

Changes in secretory pathway Ca^(2+)-ATPase 2 following focal cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2013年第1期8卷 76-82页

作者： Tonglin Lu Zhiping Hu Liuwang Zeng zheng jiang Department of Neurology Second Xiangya Hospital Central South University

This study aimed to investigate changes in secretory pathway Ca2＋-ATPase 2 expression following cerebral ischemia/reperfusion injury, and to define the role of Ca2＋-ATPases in oxidative stress. A rat model of cerebral ischemia/reperfusion injury was established using the unilateral middle cerebral artery occlusion method. Immunohistochemistry and reverse transcription-PCR assay results showed that compared with the control group, the expression of secretory pathway Ca2＋-ATPase 2 protein and mRNA in the cerebral cortex and hippocampus of male rats did not significantly change during the ischemic period. However, secretory pathway Ca2＋-ATPase 2 protein and mRNA expression reduced gradually at 1, 3, and 24 hours during the reperfusion period. Our experimental findings indicate that levels of secretory pathway Ca2＋-ATPase 2 protein and mRNA expression in brain tissue change in response to cerebral ischemia/reperfusion injury.

关键词： neural regeneration brain injury cerebral infarction secretory pathway Ca2+-ATPase 2 Golgiapparatus Ca2+ oscillations manganese focal cerebral ischemia oxidative damage Ca2^-ATPase grants-supported paper photographs-containing paper neuroregeneration