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Nuclear Science and Techniques 2023年第2期34卷 1-12页

作者： yu‑ying li Chang‑yu li Kun Hu Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China

With the development of silicon photomultiplier(SiPM)technology,front-end electronics for SiPM signal processing have been highly sought after in various fields.A compact 64-channel front-end electronics(FEE)system achieved by fieldprogrammable gate array-based charge-to-digital converter(FPGA-QDC)technology was built and *** FEE consists of an analog board and FPGA *** analog board incorporates commercial amplifiers,resistors,and *** FPGA board is composed of a low-cost *** electronics performance of the FEE was evaluated in terms of noise,linearity,and uniformity.A positron emission tomography(PET)detector with three different readout configurations was designed to validate the readout capability of the FEE for SiPM-based *** PET detector was made of a 15×15 lutetium–yttrium oxyorthosilicate(LYSO)crystal array directly coupled with a SiPM array *** experimental results show that FEE can process dual-polarity charge signals from the SiPM *** addition,it shows a good energy resolution for 511-keV gamma photons under the dual-end readout for the LYSO crystal array irradiated by a Na-22 ***,the FEE based on FPGA-QDC shows promise for application in SiPM-based radiation detectors.

关键词： Readout electronics Charge measurement Radiation detector Silicon photomultiplier Field-programmable gate array

Acidogenic sludge fermentation to recover soluble organics as the carbon source for denitrification in wastewater treatment： Comparison of sludge types

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Frontiers of Environmental Science & Engineering 2018年第4期12卷 25-32页

作者： lin lin ying-yu li Xiao-yan li Environmental Engineering Research Centre Departmelt of Civil Engineering The University of Hong Kong Pokfulam Hong Kong China Shenzhen Engineering Research Laboratory for Sludge and Food Waste Treatment and Resource Recovery Graduate School at Shenzhcn Tsinghua University Shcnzhen 518055 China＊

For biological nitrogen （N） removal from wastewater, a sufficient organic carbon source is requested fbr denitrification. However. the organic carbon/nitrogen ratio in municipal wastcwatcr is becoming lower in recent years, which increases the demand for the addition of external organic carbon, e.g. methanol, in wastewater treatment. The volatile fatty acids （VFAs） produced by acidogenic fenncntation of sewage sludge can be an attractive alternative for methanol. Chemically enhanced primary sedimentation （CEPS} is an effective process that applies chemical coagulants to enhance the removal of organic pollutants and phosphorus from wastewater by sedimentation. In temls of the chemical and biological characteristics, the CEPS sludge is considerably different from the conventional primary and secondary sludge. In the present study, FeCI3 and PACI （polyalunfinum chloride） were used as the coagulants for CEPS treatment of raw sewage. The derived CEPS sludge （Fe-sludge and Al-sludge） was then processed with mcsophilic acidogenic fennentation to hydrolysc the solid organics and produce VFAs for organic carbon recovery, and the sludge acidogenesis efficiency was compared with that of the conventional primary sludge and secondary sludge. The results showed that the Fe-sludge exhibited the highest hydrolysis and acidogenesis efficiency, while the Al-sludge and secondary＇ sludge had lower hydrolysis efficiency than that of primary sludge. Utilizing ffie Fc-sludgc fermentation liquid as tbc carbon source for denitrificatiom more than 99%of nitrate removal was achieved in the main-stream wastewater treatment without any external carbon addition, instead of 35% obtained from the conventional process of primary sedimentation followed by the oxic/anoxic （O/A） treatment.

关键词： Sewage sludge Chemically enhanced primary sedimentation(CEPS) Acidogenic fermentation Organic carbon recovery Nitrogen removal

A Note on Symplectic Algorithm

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Communications in Theoretical Physics 2001年第7期36卷 11-18页

作者： GUO Han-ying li yu-Qi WU Ke Institute of Theoretical Physics Academia Sinica P.O. Box 2735 Beijing 100080 China Institute of Theoretical Physics Academia Sinica P.O. Box 2735 Beijing 100080 China Institute of Theoretical Physics Academia Sinica P.O. Box 2735 Beijing 100080 China

We present the symplectic algorithm in the Lagrangian formalism for the Hamiltonian systems by virtue of the noncommutative differential calculus with respect to the discrete time and the Euler-Lagrange cohomological ... 详细信息

关键词： symplectic algorithm, Lagrangian formalism, Euler-Lagrange cohomology

Multi-physical fields distribution in billet during helical electromagnetic stirring:A numerical simulation research

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China Foundry 2024年第1期21卷 51-59页

作者： Dong Pan Qing-tao Guo Kai-lun Zhang Fu-zhi yu yu-ying li yu-bao Xiao State Key Laboratory of Metal Materials for Marine Equipment and Application Anshan 114009LiaoningChina Ansteel Beijing Research Institute Co. Ltd.Beijing 102200China

Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting *** from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimensional flow of molten metal and eliminating solidification *** this study,the single-winding helical stirring(SWHS)was introduced,offering advantages such as smaller volume and lower electromagnetic shielding compared to traditional helical stirring *** a comprehensive numerical simulation,the stirring parameters of SWHS were adjusted to yoke inclination angle of 43°and frequency of 12 *** higher electromagnetic force and flow velocity in drawing direction,as well as the lower temperature gradient induced by the SWHS,are positive factors for homogeneous solidification of *** experimental results on Al-8%Si alloy and 0.4%C-1.1%Mn steel demonstrate that compared to rotate stirring,the SWHS process can induce better billet quality and is more effective in accelerating the equiaxed expansion and reducing element *** SWHS process can enhance the equiaxed ratio of the billet by 58.3%and reduce segregation degree of carbon element by 10.97%.Consequently,SWHS holds great promise as a potential approach for improving the quality of continuous casting billets.

关键词： billet electromagnetic stirring helical solidification element segregation numerical simulation

Effect of Micro-Area pH Value on Formation of Different Rust Phases of Weathering Steel in Initial Corrosion Period

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Journal of Iron and Steel Research International 2010年第9期17卷 69-72,78页

作者： CHEN Xiao-ping WANG Xiang-dong liU Qing-you MI Feng-yi CHEN ying li yu-su Central Iron and Steel Research Institute Beijing 100081 China

The formation of protective rust layer of atmospheric corrosion resistance was discussed for weathering steel. The rust layers of experimental steels were made by using an accelerating industrial atmospheric corrosion test of dry-wet cyclic immersion. Furthermore XRD were used to measure and analyze the rust layers. The initial corrosion processes below thin water film were observed and the changes of micro-area pH value were measured. The results are as follows： The corrosion processes of P-RE weathering steel are obviously different from those of carbon steel. The surface of P-RE weathering steel rapidly forms a-FeOOH and the micro-area pH value is above 5.4 during the initial corrosion period. While the component of the rust layer for the carbon steel is mainly Fe3O4 and the microarea pH value is below 3.8.

关键词： weathering steel pH value micro area rust phase

SOliD PHASE TRANSITION OF SYNDIOTACTIC POLYSTYRENE IN SUPERCRITICAL CO_2

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Chinese Journal of Polymer Science 2002年第3期20卷 191-196页

作者： yu-ying li Jia-song He State Key Laboratory of Engineering Plastics, Center for Molecular Science, Institute of Chemistry Chinese Academy of Sciences, Beijing 100080 China Chinese Acad Sci Inst Chem Ctr Mol Sci State Key Lab Engn Plast Beijing 100080 Peoples R China

Solid phase transition of the a form crystals to the 3 form crystals in syndiotactic polystyrene (sPS) samples has occurred in supercritical CO2. This transformation is different from those detected under other conditions. The effects of some factors (e.g. time, temperature, and pressure) on the solid phase transformation of sPS in supercritical CO2 were analyzed in detail. Experimental results show that longer time, higher temperature or higher pressure favors the transformation of the a form crystals to the beta form crystals.

关键词： solid phase transition syndiotactic polystyrene supercritical CO2

Nischarin-siRNA delivered by polyethyleniminealginate nanoparticles accelerates motor function recovery after spinal cord injury

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Neural Regeneration Research 2017年第10期12卷 1687-1694页

作者： yue-min Ding yu-ying li Chu Wang Hao Huang Chen-chen Zheng Shao-han Huang Yang Xuan Xiao-yi Sun Xiong Zhang Department of Clinical Medicine School of MedicineZhejiang University City CollegeHangzhouZhejiang ProvinceChina Department of Physiology School of MedicineQuzhou College of TechnologyQuzhouZhejiang ProvinceChina Department of Pharmacy Zhejiang University City CollegeHangzhouZhejiang ProvinceChina Department of Basic Medicine College of MedicineZhejiang UniversityHangzhouZhejiang ProvinceChina

A previous study by our group found that inhibition of nischarin promotes neurite outgrowth and neuronal regeneration in Neuro-2 a cells and primary cortical *** recent years,more and more studies have shown that nanomaterials have good prospects in treatment of spinal cord *** proposed that small interfering RNA targeting nischarin（Nis-si RNA） delivered by polyethyleneimine-alginate（PEIALG） nanoparticles promoted motor function recovery in rats with spinal cord *** microinjection of 5 μL PEI-ALG/Nis-si RNA into the spinal cord lesion area of spinal cord injury rats was *** day 7 after surgery,Basso,Beattie and Bresnahan score was significantly higher in rats from the PEI-ALG/Nis-si RNA group compared with the spinal cord injury group and PEI-ALG/Control-si RNA *** day 21 after injection,hematoxylin-eosin staining showed that the necrotic area was reduced in the PEI-ALG/Nis-si RNA *** and western blot assay results confirmed successful inhibition of nischarin expression and increased protein expression of growth-associated protein-43 in the PEI-ALG/Nis-si RNA *** findings suggest that a complex of PEI-ALG nanoparticles and Nis-si RNA effectively suppresses nischarin expression,induces expression of growth-associated protein-43,and accelerates motor function recovery after spinal cord injury.

关键词： nerve regeneration spinal cord injury polyethylenimine alginate nanoparticles nischarin small interfering RNA necrotic area growth-associated protein-43 motor function neural regeneration

Kinetics of Nonisothermal and Isothermal Crystallization of Metallocene Polyethylene

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Chinese Chemical Letters 1999年第2期10卷 175-178页

作者： yu ying li Ji Jun ZENG Jia Song HE(State Key Laboratory of Engineering Plastics, Institute of Chemistry,The Chinese Academy of Sciences. Beijing 100080) Chinese Acad Sci Inst Chem State Key Lab Engn Plast Beijing 100080 Peoples R China

The kinetics of nonisothermal and isothermal crystallization of metallocene catalyzed and conventional polyethylenes has been studied by differential scanning calorimetry. Using Avrami equation, Ozawa theory and Mo Zhishen method, the experimental data have been analyzed. It is shown that metallocene polyethylene possesses a higher rate of crystallization due to a higher stereoregularity of its molecular chains. Moreover, they have different nonisothermal crystallization mechanisms and identical isothermal crystallization mechanisms.

关键词： metallocene polyethylene nonisothermal crystallization isothermal crystallization

Effects of upstream tirofiban versus downstream tirofiban on myocardial damage and 180-day clinical outcomes in high-risk acute coronary syndromes patients undergoing percutaneous coronary interventions

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Chinese Medical Journal 2009年第15期122卷 1732-1737页

作者： liU Tao XIE ying ZHOU yu-jie li yue-ping MA Han-ying GUO Yong-he liU yu-yang ZHAO ying-xin SHI Dong-mei Department of Geriatric Cardiology Beijing Anzhen Hospital Affiliated to Capital Medical University Beijing 100029 China

Background For patients with moderate to high-risk acute coronary syndromes （ACS） who undergo early, invasive treatment strategies, current guidelines recommend the usage of glycoprotein （GP） lib/Ilia inhibitors as an upstream treatment for a coronary care unit or as an downstream provisional treatment for selected patients who are undergoing percutaneous coronary intervention （PCI）. The relative advantage of either strategy is unknown. The purpose of this study was to evaluate the effects of upstream tirofiban versus the effects of downstream tirofiban on myocardial damage and 180-day major adverse cardiovascular events （MACE） after PCI in high-risk non-ST-segment elevation ACS （NSTE-ACS） undergoing PCI. Methods From July 2006 to July 2007, 160 high-risk NSTE-ACS undergoing PCI were randomized to receive upstream （within 4-6 hours before coronary angiography） tirofiban or downstream （the guidewire crossing the lesion） tirofiban, to evaluate the extent of myocardial damage after PCI by quantitatively and qualitatively analyzing the value of cardiac troponin I （cTnl） as well as MB isoenzyme of creatine kinase （CK-MB） before and after PCI. The incidences of 24-hour, 3-day, 7-day, 30-day and 180-day MACE after PCI were followed up and the rates of bleeding complications and thrombocytopenia during tirofiban administration were recorded. Results The peak release and cumulative release of cTnl levels within 48 hours after PCI were significantly lower with upstream tirofiban than downstream tirofiban （0.45 vs 0.63 and 0.32 vs 0.43, respectively; P 〈0.05）. Post-procedural cTnl elevation within 48 hours was significantly less frequent among patients who received the upstream tirofiban than those who received the downstream tirofiban （66.3% vs 87.5%, P 〈0.05）. The peak and cumulative release of CK-MB levels as well as post-procedural CK-MB elevation within 48 hours after PCI were not significantly different between the two groups （16 vs 14,5 vs 3 and 26.3% vs 36.3%, respecti

关键词： tirofiban coronary syndrome, acute angioplasty, transluminal, percutaneous coronary

Investigation of Dynamic Behavior in 1D Non-uniform Granular System

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Communications in Theoretical Physics 2005年第3X期44卷 551-554页

作者： ZHANG Duan-Ming SU Xiang-ying yu Bo-Ming li Rui PAN Gui-Jun SUN Hong-Zhang YIN Yan-Ping SUN Fan HE Min-Hua liU Dan Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

We present a non-uniform granular system in one-dimensional case, whose granularity distribution has the fractal characteristic. The particles are subject to inelastic mutual collisions and obey Langevin equation between collisions. By Monte Carlo simulation we study the dynamic actions of the system. Far from the equilibrium, i.e., τ 〉〉 τe, the results of simulation indicate that the inhomogeneity of the system and the inelasticity of the particles have great influences on the dynamic properties of the system, and correspondingly the influence of the inhomogeneity is more significant.

关键词： inelasticity restitution coefficient e inhomogeneity fractal dimension D non-uniform granular system