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A series of carbosilane dendrimers with acetyl end-group:From synthesis to their unique optical characteristics

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Chinese Chemical Letters 2009年第9期20卷 1085-1087页

作者： Wen Yan Sun Hai Feng Lu Deng xu wang sheng Yu Feng School of Chemistry and Chemical Engineering Shandong University Ji'nan 250100 China

A series of c arbosilane dendrimers with acetyl end-group were synthesized. Their structures were characterized by 1H NMR, IR, and MS, respectively. Then dendrimers were coordinated with lanthanide ions （Eu3＋ and Tb3＋, respectively）. The luminescence spectra of the complexes show narrow-width emissions in visible light region. 2009 sheng Yu Feng. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Synthesis Carbosilane dendrirner Luminescence Lanthanide ions

Thermal Resistance Testing Technology Research of Integration High Power-LED

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 106-110页

作者： Ping xue Chang-Hong Jia xu-sheng wang Hao Sun Optic & Electronic Engineering Research Center Harbin University of Science and Technology

In this paper,high-power LED with many integrated chips is used as thermal resistance analysis research object, and we do thermal resistance testing technology research on it. We put forward the thermocouple point contact test method. According to the principle that LED forward voltage changes with temperature,LED heat sink to surface temperature distribution is studied directly in the test,and then we analyze the thermal resistance of high-power LED with many integrated chips when its secondary packaging is introduced. This method makes the measurement of thermal resistance of LED more rapid and convenient. It provides an effective assessment method for the analysis of high power LED device design and engineering application.

关键词： thermal resistance junction temperature integrated high power LED cooling

Molecular composition of low-temperature oxidation products of the heavy oil

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Petroleum Science 2023年第5期20卷 3264-3271页

作者： Shuai Ma Yun-Yun Li Ri-Gu Su xu-sheng wang Jing-Jun Pan Quan Shi Guang-Zhi Liao Chun-Ming xu State Key Laboratory of Heavy Oil Processing Petroleum Molecular Engineering Center(PMEC)China University of PetroleumBeijing102249China Engineering Technology Research Institute of PetroChina Xinjiang Oilfield Company Karamay834000XinjiangChina CAS Lanzhou Institute of Chemical Physics Lanzhou730000GansuChina PetroChina Exploration&Production Company Beijing100007China

Low-temperature oxidation(LTO)is the main reaction that affects fuel formation in the in-situ combustion process,which has important significance for the subsequent combustion propulsion and the successful extraction of crude *** this study,heavy oil was subjected to LTO reactions at different *** types of reaction products with varying oxidation depths were characterized in terms of the number of oxygen atoms and the polarity of the molecule to reveal the low-temperature oxidation process of the heavy *** compounds and acid polyoxides in the oil phase and deep oxidation products with a higher number of oxygen atoms in the coke were identified with increasing oxidation *** experimental results showed that the oxidation reaction of the heavy oil changed from kinetic-controlled to diffusion-controlled in the open oxidation system of the heavy oil as the oxidation depth *** oxidation reaction of the oil phase reached a maximum and stable value in oxygen *** molecular compositions of the ketone compound and acid polyoxide did not change significantly with further increase in reaction *** molecular compositions of the deep oxidation products with a higher number of oxygen atoms in the coke phase changed *** coke precursor molecules with a lower oxygen content and condensation degree participated in the coke formation,and the oxidation reaction pathway and the complexity of the oxidation product component also increased.

关键词： Low-temperature oxidation In-situ combustion Heavy oil Coke precursor Molecular composition

Mechanism of over-activation in direct pathway mediated by dopamine D_1 receptor in rats with levodopa-induced dyskinesias

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Neuroscience Bulletin 2006年第3期22卷 159-164页

作者： xue-Bing CAO Qiang GUAN Yan xu Lan wang sheng-Gang SUN Department of Neurology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430022 China

Objective To study the changes of prodynorphin （PDyn） gene expression and dopamine and cAMPregulated phosphoprotein of 32 kDa （DARPP-32） phosphorylation in rats with levodopa-induced dyskinesias （LID）, and to explore the mechanism of over-activation in direct pathway mediated by dopamine D1 receptor. Methods Parkinson＇s disease （PD） rats were received levodopa （10 mg/kg, i.p.） for 28 d to get the LID rats. According to the behavior scale, LID rats were divided into mild （n=8） and severe （n=16） groups. On day 29, 8 rats in severe LID group were given an acute intraperitoneal injection of MK-801 （0.1 mg/kg） 15 min before levodopa treatment （MK-801 group, n=8）. The normal rats received same course and dosage of levodopa as the control group （n=8）. Hybridization in situ was used to measure the expression of PDyn mRNA in striatum. Protein and mRNA levels of total DARPP-32 and phospho-Thr-34 DARPP-32 level were measured by immunoblotting and RT-PCR, respectively. Results The levels of PDyn mRNA and phospho-Thr-34 DARPP-32 increased significantly in LID rats compared with control rats （P〈0.01）, and they also increased markedly in severe LID group compared with mild group （P〈0.01）. Conclusion Phospho-Thr-34 DARPP-32 level was increased in LID rats, which contributed to the over-activation of direct pathway mediated by dopamine D1 receptor.

关键词： levodopa-induced dyskinesias Prodynorphin Dopamine and cAMP-regulated phosphoprotein of 32 kDa

Improvement and Implementation of Embedded Fiber Bragg Grating Sensor Signal De-module

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 118-123页

作者： Hong-Min wang xu-sheng wang Chang-Hong Jia Kong-Qi Li Xiao-Fei Hu Hai-Qing Guo College of Automation Harbin University of Science and Technology

This paper focused on high-precision demodulation of wavelength shift of FBG sensor. Fiber tunable F-P filer was used as a demodulation method. 32-bit embedded processor ARM9-S3C2440 chip was used as the main controller and simulated annealing algorithm was realized on ARM to demodulate wavelength signal. Simulation results show that the simulated annealing algorithm is reliable to process analog signals on ARM chip and significant performance is achieved such as saving bandwidth,increasing the amounts of reusable fiber grating sensors in sensor system and speeding up data processing.

关键词： embedded fiber bragg grating simulated annealing algorithm

The Simulation and Experimental Validation on Gas-Solid Two Phase Flow in the Riser of a Dense Fluidized Bed

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Journal of Thermal Science 2009年第2期18卷 137-141页

作者： xue-yao wang Fan Jiang Xiang xu sheng-dian wang Bao-guo Fan Yun-han Xiao Key Laboratory of Advanced Energy and Power, Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing 100190 Key Laboratory of Advanced Energy and Power Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing China

Gas-solid flow in dense CFB (circulating fluidized bed)) riser under the operating condition, superficial gas 15.5m/s and solid flux 140 kg/m2s using Geldart B particles (sand) was investigated by experiments and CFD (computationalfluid dynamics) simulation. The overall and local flow characteristics are determined using the axialpressure profiles and solid concentration profiles. The cold experimental results indicate that the axial solid concentration distribution contains a dilute region towards the up-middle zone and a dense region near the bottomand the top exit zones. The typical core-annulus structure and the back-mixing phenomenon near the wall of theriser can be observed. In addition, owing to the key role of the drag force of gas-solid phase, a revised drag forcecoefficient, based on the EMMS (energy-minimization multi-scale) model which can depict the heterogeneouscharacter of gas-solid two phase flow, was proposed and coupled into the CFD control equations. In order to findan appropriate drag force model for the simulation of dense CFB riser, not only the revised drag force model butsome other kinds of drag force model were used in the CFD. The flow structure, solid concentration, clustersphenomenon, fluctuation of two phases and axial pressure drop were analyzed. By comparing the experimentwith the simulation, the results predicted by the EMMS drag model showed a better agreement with the experimentalaxial average pressure drop and apparent solid volume fraction, which proves that the revised drag forcebased on the EMMS model is an appropriate model for the dense CFB simulation.

关键词： riser gas-solid flow drag force EMMS model

Overview of in-situ oxygen production technologies for lunar resources

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 233-255页

作者： Youpeng xu sheng Pang Liangwei Cong Guoyu Qian Dong wang Laishi Li Yusheng Wu Zhi wang College of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China CAS Key Laboratory of Green Process and Engineering National Engineering Research Center for Green Recycling of Strategic Metal ResourcesInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial ***,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic *** oxygen and metal extraction can be achieved using existing metallurgical ***,the ample reserves of water ice on the Moon offer another means for oxygen *** paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental *** delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar *** two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the *** the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the *** review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives.

关键词： lunar resources in-situ oxygen production space metallurgy molten lunar regolith electrolysis

Prediction of Anoxic Sulfide Biooxidation Under Various HRTs Using Artificial Neural Networks

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Biomedical and Environmental Sciences 2007年第5期20卷 398-403页

作者： QAISAR MAHMOOD PING ZHENG DONG-LEI WU xu-sheng wang HAYAT YOUSAF EJAZ UL-ISLAM MUHAMMAD JAFFAR HASSAN GHULAM JILANI MUHAMMAD RASHID AZIM Department of Environmental Engineering College of Environment and Resource Science Zhejiang University Hangzhou 310029 Zhejiang China Institute of Statistical Genetics Zhejiang University Hangzhou 310029 Zhejiang China tUniversity of Arid Agriculture Rawalpindi Pakistan University of Arid Agriculture Rawalpindi Pakistan Federal Government Post-graduate College Sector H-8 Islamabad Pakistan

Objective During present investigation the data of a laboratory-scale anoxic sulfide oxidizing （ASO） reactor were used in a neural network system to predict its performance. Methods Five uncorrelated components of the influent wastewater were used as the artificial neural network model input to predict the output of the effluent using back-propagation and general regression algorithms. The best prediction performance is achieved when the data are preprocessed using principal components analysis （PCA） before they are fed to a back propagated neural network. Results Within the range of experimental conditions tested, it was concluded that the ANN model gave predictable results for nitrite removal from wastewater through ASO process. The model did not predict the formation of sulfate to an acceptable manner. Conclusion Apart from experimentation, ANN model can help to simulate the results of such experiments in finding the best optimal choice for ASO based denitrification. Together with wastewater collection and the use of improved treatment systems and new technologies, better control of wastewater treatment plant （WTP） can lead to more effective maneuvers by its operators and, as a consequence, better effluent quality.

关键词： Artificial neural networks Effluent sulfide prediction Effluent nitrite prediction Principal components analysis Wastewater treatment ASO reactor

Neuroprotective effect of the Chinese medicine Tiantai No.1 and its molecular mechanism in the senescence-accelerated mouse prone 8

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Neural Regeneration Research 2017年第2期12卷 301-306页

作者： Ying-hong Li xu-sheng wang Xiao-lin Chen Yu Jin Hong-bo Chen Xiu-qin Jia Yong-feng Zhang Zheng-zhi Wu First Affiliated Hospital of Shenzhen University (Shenzhen Second People's Hospital) Shenzhen Guangdong Province China School of Life Sciences Tsinghua University Beijing China Guangzhou Medical University Guangzhou Guangdong Province China Shenzhen Key Laboratory of Health Sciences and Technology Graduate School at Shenzhen Tsinghua University Beijing China

Tiantai No.1, a Chinese medicine predominantly composed of powdered Rhizoma Gastrodiae, Radix Ginseng, and Ginkgo leaf at a ratio of 2：1：2 and dissolved in pure water, is neuroprotective in animal models of various cognitive disorders, but its molecular mechanism remains unclear. We administered Tiantai No.1 intragastrically to senescence-accelerated mouse prone 8（SAMP8） mice（a model of Alzheimer＇s disease） at doses of 50, 100 or 150 mg/kg per day for 8 weeks and evaluated their behavior in the Morris water maze and expression of Alzheimer＇s disease-related proteins in the brain. Tiantai No.1 shortened the escape latency in the water maze training trials, and increased swimming time in the target quadrant during the spatial probe test, indicating that Tiantai No.1 improved learning and memory in SAMP8 mice. Immunohistochemistry revealed that Tiantai No.1 restored the proliferation potential of Ki67-positive cells in the hippocampus. In addition, mice that had received Tiantai No.1 had fewer astrocytes, and less accumulation of amyloid-beta and phosphorylated tau. These results suggest that Tiantai No.1 is neuroprotective in the SAMP8 mouse model of Alzheimer＇s disease and acts by restoring neuronal number and proliferation potential in the hippocampus, decreasing astrocyte infiltration, and reducing the accumulation of amyloid-beta and phosphorylated tau.

关键词： nerve regeneration neuroprotective effects Alzheimer's disease Tiantai No.1 SAMP8 amyloid-beta autophagy-lysosome pathway ubiquitin proteasome pathway tau phosphorylation neuronal apoptosis astrocytosis neural regeneration