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China Foundry 2022年第3期19卷 191-200页

作者： Yong-hui Jia Cheng-lu Hu qi-chi Le Wen-yi Hu Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Longyan University College of Chemistry and Materials ScienceLongyan 364012FujianChina

Based on multi-physical field coupling numerical simulation method,magnetic field distribution,melt flow,and heat transfer behavior of aΦ300 mm AZ80 alloy billet during differential phase electromagnetic DC casting(DP-EMC)with different electromagnetic parameters were *** results demonstrate that the increase in current intensity only changes the magnitude but does not change the Lorentz force's distribution *** maximum value of the Lorentz force increases linearly followed by an increase in current *** the frequency increases,the Lorentz force's r component remains constant,and the z component decreases *** change in current intensity correlates with the melt oscillation and convection intensity positively,as well as the liquid sump temperature *** does not mean that the higher the electric current,the better the metallurgical quality of the billet.A lower frequency is beneficial to generate a more significant melt flow and velocity fluctuation,which is helpful to create a more uniform temperature *** DP-EMC parameters for aΦ300 mm AZ80 Mg alloy are 10-20 Hz frequency and 80-100 A current intensity.

关键词： heat transfer melt flow differential phase electromagnetic field DC casting Mg alloy

Local boundary dilatation of quasiconformal maps

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Science China Mathematics 2005年第6期48卷 798-807页

作者： qi yi Department of Applied Mathematics LIMB of the Ministry of Education Beijing University of Aeronautics and Astronautics Beijing 100083 China

By studying the existence problem of locally extremal Beltrami differential posed by F. Gardiner and N. Lakic, we introduce a new definition of the local boundary dilatations of points in Teichmuller spaces of simply connected plane domains, which is the same as the usual ones in the case of Jordan domains. Then we show that the answer to the problem of F. Gardiner and N. Lakic is affirmative according to this new definition. Comparing with the usual definitions, the problem of F. Gardiner and N. Lakic is partly answered and the results of G. Cui and Y. qi is generalized.

关键词： quasiconformal map Teichmiiiler space.

Structure and Properties of β-Polypropylene Reinforced by Polypropylene Fiber and Polyamide Fiber

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Chinese Journal of Polymer Science 2014年第4期32卷 509-518页

作者： qi Liu hui-hui Li 闫寿科 State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

Matrix/fiber composites of,β-form isotactic polypropylene （iPP） matrix and α-iPP or PA6 fibers were prepared by laminating technique under different preparation temperatures. The mechanical properties and interracial morphologies of these composites were studied by tensile test, optical microscopy and scanning electron microscopy, respectively. The experimental results show that the tensile yield load and tensile modulus of β-iPP/PA6 matrix/fiber systems increased significantly at the expense of elongation at break. These mechanical properties show essentially no dependence on the sample preparation temperature. On the other hand, the mechanical properties of iPP matrix/fiber single polymer composites depend strongly on the sample preparation temperature. At low sample preparation temperature, e.g., 172 ℃, the solid cr-iPP fiber induces tr-iPP crystallization, leading to the formation of a-iPP transcrystalline layer around the fiber. This results in a remarkable increment of the tensile yield load and tensile modulus. The elongation at break is also much better than that of the iPP/PA6 matrix/fiber system. It reflects a better interracial adhesion of the single polymer composite compared with the iPP/PA6 composite. At higher sample preparation temperature, e.g., 174 ℃ or 176 ℃, the partial surface melting of the oriented fiber allows interdiffusion of iPP molecular chains in the molten fiber and matrix melt. The penetration of matrix chains into the molten iPP fiber results in some iPP molecular chains being included partially in the recrystallized fiber and the induced β-transcrystalline layers. This kind of configuration leads to an improvement of interfacial adhesion between the fiber and matrix, which causes a simultaneous increase of the tensile yield load, tensile modulus and elongation at break of β-iPP.

关键词： Polypropylene Composite Mechanical property Interfacial morphology.

Changes in the Cytokine Profiles of Patients with Chronic Hepatitis B during Antiviral Therapy

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Biomedical and Environmental Sciences 2021年第6期34卷 443-453页

作者： LI Ming hui LU hui hui CHEN qi qi LIN Yan Jie ZENG Zhan LU Yao ZHANG Lu DONG Jian Ping yi Wei XIE Yao Department of Hepatology Division 2 Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Department of Hepatology Division 2 Peking University Ditan Teaching HospitalBeijing 100015China Department of Infectious Diseases Haidian HospitalBeijing Haidian Section of Peking University Third HospitalBeijing 100080China Department of Gynecology and Obstetrics Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China

Objective To investigate the changes in the cytokine profiles of chronic hepatitis B(CHB)patients undergoing antiviral *** Hepatitis B e antigen(HBeAg)-positive patients were treated with Pegylated interferon(PEGIFN)and entecavir(ETV).Clinical biochemistry and cytokines were detected at baseline and every 3 *** In all,200 patients completed 48 weeks of treatment,100 in the PEG-IFN group and 100 in the ETV *** 3–6 months of treatment,compared with baseline,the PEG-IFN group showed a significant decrease in interferon-gamma(IFN-γ),interleukin-17 A(IL-17 A),interleukin-6(IL-6),interleukin-10(IL-10),and transforming growth factor beta(TGF-β)(P<0.001)and a significant increase in interferon-alpha 2(IFN-α2)(P<0.001).In the ETV group,IL-10 and TGF-β1 decreased significantly(P<0.001).After 3 months,the levels of IFN-α2,IL-17 A,and tumor necrosis factor-alpha(TNF-α)in the PEGIFN group were significantly higher than those in the ETV group(P<0.01).The levels of IL-6 and TGF-β3 were significantly lower than those in the ETV group(P<0.01).After 6 months,the levels of IFN-α2,IFN-γ,and TNF-αin the PEG-IFN group were significantly higher than those in the ETV group(P<0.01),while the levels of IL-6 and TGF-β3 were significantly lower than those in the ETV group(P<0.01).Compared with ETV,PEG-IFN had higher HBeAg and HBsAg disappearance *** During antiviral therapy,a change in the cytokine profile occurred;in the aspect of immune control and functional cure,PEG-IFN was significantly better than ETV.

关键词： Chronic hepatitis B Cytokine Interferon Nucleoside(nucleotide)analog

An online electricity cost budgeting algorithm for maximizing green energy usage across data centers

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Frontiers of Computer Science 2017年第4期11卷 661-674页

作者： hui DOU Yong qi School of Electronic and Information Engineering Xi'an Jiaotong University Xi'an 710049 China

With the sky-rocketing development of Internet services, the power usage in data centers has been signifi- cantly increasing. This ever increasing energy consumption leads to negative environmental impact such as global warming. To reduce their carbon footprints, large Internet service operators begin to utilize green energy. Since green energy is currently more expensive than the traditional brown one, it is important for the operators to maximize the green en- ergy usage subject to their desired long-term （e.g., a month） cost budget constraint. In this paper, we propose an online algorithm GreenBudget based on the Lyapunov optimization framework. We prove that our algorithm is able to achieve a delicate tradeoff between the green energy usage and the en- forcement of the cost budget constraint, and a control parameter V is the knob to arbitrarily tune such a tradeoff. We evaluate GreenBudget utilizing real-life traces of user requests, cooling efficiency, electricity price and green energy avail- ability. Experimental results demonstrate that under the same cost budget constraint, GreenBudget can increase the green energy usage by 11.55% compared with the state-of-the-art work, without incurring any performance violation of user requests.

关键词： electricity cost budgeting green energy coolingefficiency data center Lyapunov optimization

Distribution and mode of occurrence of uranium in bottom ash derived from high-germanium coals

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Journal of Environmental Sciences 2016年第5期28卷 91-98页

作者： yinglong Sun Guangxia qi Xuefei Lei hui Xu Lei Li Chao Yuan yi Wang Department of Environmental Engineering School of Environment Tsinghua University Department of Environmental Science and Engineering School of Food and Chemical EngineeringBeijing Technology and Business University

The radioactivity of uranium in radioactive coal bottom ash（CBA） may be a potential danger to the ambient environment and human health. Concerning the limited research on the distribution and mode of occurrence of uranium in CBA, we herein report our investigations into this topic using a number of techniques including a five-step Tessier sequential extraction, hydrogen fluoride（HF） leaching, Siroquant（Rietveld） quantification, magnetic separation, and electron probe microanalysis（EPMA）. The Tessier sequential extraction showed that the uranium in the residual and Fe–Mn oxide fractions was dominant（59.1%and 34.9%, respectively）. The former was mainly incorporated into aluminosilicates,retained with glass and cristobalite, whereas the latter was especially enriched in the magnetic fraction, of which about 50% was present with magnetite（Fe_3O_4） and the rest in other iron oxides. In addition, the uranium in the magnetic fraction was 2.6 times that in the non-magnetic fraction. The experimental findings in this work may be important for establishing an effective strategy to reduce radioactivity from CBA for the protection of our local environment.

关键词： Coal bottom ash Uranium Radioactivity Tessier sequential extraction Magnetic separation

Evaluation of spatial-temporal dynamics in surface water temperature of qinghai Lake from 2001 to 2010 by using MODIS data

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Journal of Arid Land 2013年第4期5卷 452-464页

作者： Fei XIAO Feng LING Yun DU qi FENG yi YAN hui CHEN Institute of Geodesy and Geophysics Chinese Academy of Sciences

Lake surface water temperature （SWT） is an important indicator of lake state relative to its water chemistry and aquatic ecosystem,in addition to being an important regional climate ***,few literatures involving spatial-temporal changes of lake SWT in the qinghai-Tibet Plateau,including qinghai Lake,are *** objective is to study the spatial-temporal changes in SWT of qinghai Lake from 2001 to 2010,using Moderate-resolution Imaging Spectroradiometer （MODIS） *** on each pixel,we calculated the temporal SWT variations and long-term trends,compared the spatial patterns of annual average SWT in different years,and mapped and analyzed the seasonal cycles of the spatial patterns of *** results revealed that the differences between the average daily SWT and air temperature during the temperature decreasing phase were relatively larger than those during the temperature increasing *** increasing rate of the annual average SWT during the study period was about 0.01℃/a,followed by an increasing rate of about 0.05℃/a in annual average air *** annual average SWT from 2001 to 2010 showed similar spatial patterns,while the SWT spatial changes from January to December demonstrated an interesting seasonal reversion *** high-temperature area transformed stepwise from the south to the north regions and then back to the south region from January to December,whereas the low-temperature area demonstrated a reversed annual cyclical *** spatial-temporal patterns of SWTs were shaped by the topography of the lake basin and the distribution of drainages.

关键词： surface water temperature (SWT) spatial-temporal changes MODIS qinghai Lake

Aromatic Moieties from Matured Chicken Manure and Agriculture Residues Compost Suppress Growth of Lepidium sativum L. and Trichoderma harzianum

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Pedosphere 2013年第6期23卷 826-834页

作者： LUO yi-Hong ZHANG Dong-qing YU Guang-hui SHEN qi-Rong Agricultural Ministry Key Lab of Plant Nutrition and Fertilization in Low-Middle Reaches of the Yangtze River Jiangsu Key Lab for Organic Solid Waste UtilizationCollege of Resources and Environmental SciencesNanjing Agricultural University Baoshan Environmental Protection Bureau

To better understand the role of organic matter(OM)prepared from chicken manure and agriculture residues compost on the growth of plants(Lepidium sativum L.)and antagonistic fungi(Trichoderma harzianum),we analyzed the structure and composition of extracted OM using fluorescence excitation-emission matrix(EEM)spectroscopy and solid-state13C cross-polarization magic-anglespinning nuclear magnetic resonance(13C CPMAS NMR)*** results showed that the EEM contours of water-extracted OM(WEOM)and alkali-extracted OM(AEOM)were ***,solid-state13C CPMAS NMR spectroscopy demonstrated that water extraction could not proportionally pull out aromatic moieties(112–145 ppm)from compost,but the alkali method in proportion extracted both carbohydrates(65–85 ppm)and aromatic *** results suggest that AEOM may better reflect the bulk OM composition of compost,and one should be cautious when applying WEOM as an alternative indicator of total compost *** investigations demonstrated that,compared to carbohydrates,aromatic moieties played a predominant role in growth suppression of Lepidium sativum *** and Trichoderma harzianum.

关键词： excitation-emission matrix spectroscopy extracted organic matter fluorescence reginal integration analysis nuclear magnetic resonance spectroscopy

Recognition results classification and post-processing methods for painted characters on billet surface

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Advances in Manufacturing 2017年第3期5卷 261-270页

作者： qi-Jie Zhao Chun-hui Huang Zhen-Nan Ke Jin-Gang yi School of Mechatronic Engineering and Automation Shanghai Key Laboratory of Intelligent Manufacturing andRobotics Shanghai University Shanghai 200072 People's Republic of China

Automatic identification of characters marked on billets is very important for steelworks to achieve manu- facturing and logistics informatization management. Due to the presence of adhesions, fractures, blurs, and other problems in characters painted on billets, character recognition accuracy with machine vision is relatively low, and hardly meets practical application requirements. To make the character recognition results more reliable and accu- rate, an identification results classification and post-pro- cessing method has been proposed in this paper. By analyzing issues in the image segmentation and recognition stage, the recognition result classification model, based on character encoding rules and recognition confidence, is built, and the character recognition results can be classified as correct, suspect, or wrong. In the post-processing stage, a human-machine-cooperation mechanism with a post- processing interface is designed to eliminate error infor- mation in suspect and wrong types. The system was developed and experiments conducted with images acquired in an iron and steel factory. The results show the character recognition accuracy to be approximately 89% using the character recognizer. However, this result cannot be directly applied in information management systems. With the proposed post-processing method, a human worker will query the suspect and wrong results classified by the system, determine whether the result is correct or wrong, and then, correct the wrong result through the post-processing interface. Using this method, the character recognition accuracy ultimately improves to 99.4%. Thus, the results will be more reliable applied in a practical system.

关键词： Painted character· Character segmentation.Character recognition · Recognition results classification·Post-processing method

C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway as a therapeutic target and regulatory mechanism for spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2231-2244页

作者： Xiangzi Wang Xiaofei Niu yingkai Wang Yang Liu Cheng Yang Xuyi Chen Zhongquan qi School of Medicine Guangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Graduate School of Tianjin University of Traditional Chinese Medicine TianjinChina Characteristic Medical Center of People’s Armed Police Forces TianjinChina Fujian Maternity and Child Health Hospital FuzhouFujian ProvinceChina

Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory *** expression of the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis exhibits significant differences before and after *** studies have revealed that the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis is closely associated with secondary inflammatory responses and the recruitment of immune cells following spinal cord injury,suggesting that this axis is a novel target and regulatory control point for *** review comprehensively examines the therapeutic strategies targeting the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis,along with the regenerative and repair mechanisms linking the axis to spinal cord ***,we summarize the upstream and downstream inflammatory signaling pathways associated with spinal cord injury and the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 *** review primarily elaborates on therapeutic strategies that target the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the latest progress of research on antagonistic drugs,along with the approaches used to exploit new therapeutic targets within the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the development of targeted ***,there are presently no clinical studies relating to spinal cord injury that are focusing on the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 *** review aims to provide new ideas and therapeutic strategies for the future treatment of spinal cord injury.

关键词： apoptosis C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway C-C motif chemokine receptor 2 antagonists chemokine ligand 2 chemokine receptor 2 inflammation macrophage microglia spinal cord injury therapeutic method