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World Journal of Gastroenterology 2010年第4期16卷 513-517页

作者： Tang, Li-Jun Wang, Tao cui, Jian-feng Zhang, Bing-Yin Li, Shi Li, Dong-Xuan Zhou, Shu Chengdu Gen Hosp Chengdu Mil Area Command Ctr Gen Surg Chengdu 610083 Sichuan Prov Peoples R China

AIM:To introduce and evaluate the new method used in treatment of pancreatic and peripancreatic infections secondary to severe acute pancreatitis(SAP).METHODS:A total of 42 SAP patients initially underwent ultrasound-guided percutaneous puncture and *** 8-Fr drainage catheter was used to drain the infected peripancreatic necrotic foci for 3-5 *** sinus tract of the drainage catheter was expanded gradually with a skin expander,and the 8-Fr drainage catheter was replaced with a 22-Fr drainage tube after 7-10 ***-guided debridement was performed repeatedly until the infected peripancreatic tissue was effectively removed through the drainage sinus ***:Among the 42 patients,the infected peripancreatic tissue or abscess was completely removed from 38 patients and elective cyst-jejunum anastomosis was performed in 4 patients due to formation of pancreatic *** death and complication occurred during the ***:Percutaneous catheter drainage in combination with choledochoscope-guided debridement is a simple,safe and reliable treatment procedure for peripancreatic infections secondary to SAP.

关键词： Severe acute pancreatitis Peripancreatic infection Percutaneous catheter drainage Choledochoscope Debridement

17-4PH不锈钢激光气体渗氮层显微组织与摩擦学性能

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表面技术 2024年第7期53卷 57-63页

作者：刘礼邵磊孙岩茹崔梓烁李克伟李文生山东科技大学材料科学与工程学院山东青岛266590 西北师范大学物理与电子工程学院兰州730070

目的提高17-4PH马氏体沉淀硬化不锈钢的表面硬度及耐磨性。方法采用光纤激光器对17-4PH不锈钢进行激光气体氮化,采用不同激光功率在其表面制备渗氮层。利用光学显微镜(OM)、电子扫描显微镜(SEM)和X射线衍射仪(XRD)等设备分析渗氮层的显... 详细信息

目的提高17-4PH马氏体沉淀硬化不锈钢的表面硬度及耐磨性。方法采用光纤激光器对17-4PH不锈钢进行激光气体氮化,采用不同激光功率在其表面制备渗氮层。利用光学显微镜(OM)、电子扫描显微镜(SEM)和X射线衍射仪(XRD)等设备分析渗氮层的显微组织和相组成;借助显微硬度仪测试渗氮层截面深度方向的硬度;采用多功能摩擦磨损试验机测试基体、渗氮层的摩擦学性能,并通过SEM分析磨痕形貌,揭示基体与渗氮层的磨损机制。结果在渗氮前样品组织为回火马氏体,经激光渗氮后样品表面形成了由板条马氏体组成的熔化区和回火马氏体组成的热影响区构成的渗氮层。经渗氮后,样品的硬度均得到提高。在激光功率3000 W下,渗氮层的表面硬度最高,达到了415HV0.2,约是基体硬度的1.2倍,渗氮层的硬度随着深度的增加呈下降趋势,在深度为2.6mm处其硬度与基体一致。在回火马氏体向板条马氏体转变的相变强化,以及氮原子(以固溶方式进入基体)的固溶强化作用下,提高了渗氮层的硬度。经渗氮后,样品的摩擦因数均高于基体,但渗氮后其磨损量相较于基体有所减少,在激光功率3000W下,其磨损体积最小,相较于基体减少了62%。在激光功率2500W下马氏体转变不完全,在激光功率3500W下渗氮层出现了裂纹,都降低了渗氮层的硬度,其耐磨性也随之减小,且都略低于在3000W下。磨损机制由渗氮前的以黏着磨损为主,转变为渗氮后的以磨粒磨损为主。结论在17-4PH马氏体沉淀硬化不锈钢表面进行激光渗氮后,其表面硬度和耐磨性均得到提高,在激光功率3000W下制备的渗氮层具有较高的表面硬度和优异的耐磨性。

关键词：激光气体渗氮 17-4PH马氏体沉淀硬化不锈钢显微组织表面硬度摩擦学性能

飞灰含碳在线测量在660 MW机组锅炉燃烧中应用

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冶金能源 2024年第1期43卷 54-56页

作者：张超柳宁绳鹏鹏崔小军陕西德源府谷能源有限公司

针对失重法飞灰测碳装置在取样及测量方面的不足,利用防堵耐磨等技术提高飞灰测碳装置的测量精度和取样稳定性,并将装置应用于660 MW机组锅炉智慧燃烧系统中,通过精准飞灰含碳测量反映炉内燃烧状态,确保燃烧优化控制模型预测的正确性。... 详细信息

针对失重法飞灰测碳装置在取样及测量方面的不足,利用防堵耐磨等技术提高飞灰测碳装置的测量精度和取样稳定性,并将装置应用于660 MW机组锅炉智慧燃烧系统中,通过精准飞灰含碳测量反映炉内燃烧状态,确保燃烧优化控制模型预测的正确性。研究结果表明,飞灰含碳实际值与预测值误差保持在较小范围内,最大误差不超过0.015%。优化燃烧系统后的现场运行结果表明,飞灰含碳量均值由2.1%降到1.5%,锅炉效率平均提高0.21%。

关键词：飞灰含碳在线测量技术防堵耐磨智慧燃烧

Second-order two-scale analysis and numerical algorithms for the hyperbolic–parabolic equations with rapidly oscillating coefficients

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Chinese Physics B 2015年第9期24卷 40-53页

作者：董灏聂玉峰崔俊芝武亚涛 School of Science Northwestern Polytechnical University Academy of Mathematics and Systems Science Chinese Academy of Sciences

We study the hyperbolic–parabolic equations with rapidly oscillating coefficients. The formal second-order two-scale asymptotic expansion solutions are constructed by the multiscale asymptotic analysis. In addition, we theoretically explain the importance of the second-order two-scale solution by the error analysis in the pointwise sense. The associated explicit convergence rates are also obtained. Then a second-order two-scale numerical method based on the Newmark scheme is presented to solve the equations. Finally, some numerical examples are used to verify the effectiveness and efficiency of the multiscale numerical algorithm we proposed.

关键词： hyperbolic–parabolic equations rapidly oscillating coefficients second-order two-scale numerical method Newmark scheme

Microstructure and Texture Evolution of Fe-33Mn-3Si-3Al TWIP Steel on Strain

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Journal of Wuhan University of Technology(Materials Science) 2019年第1期34卷 176-182页

作者： HU Yangyang SU Yu Schoole of Materials Engineering Shanghai University of Engineering Science

The microstructure and texture evolution of Fe-33Mn-3Si-3Al twinning induced plasticity(TWIP) steel were studied by the scanning electron microscope(SEM) and X-ray diffraction(XRD) at room temperature. After quasi-static tensile, the texture evolution of different strain was observed. It was shown that the Goss and Brass components increased within the strain range of less than 0.6. Whereas, the main components were decreased when the strain levels were greater than 0.6. This behavior was attributed to the low stacking fault energy(SFE) and was related to the strain energy of this high manganese steel. At high strain levels, the high strain energy may contribute to the Brass components transition to the A(rot-Brass) components.

关键词： strain microstructure texture evolution TWIP steel strain energy

Application of headed studs in steel fiber reinforced cementitious composite slab of steel beam-column connection

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Earthquake Engineering and Engineering Vibration 2012年第1期11卷 11-21页

作者： Yao cui Masayoshi Nakashima Center for Urban Earthquake Engineering Tokyo Institute of Technology Japan Disaster Prevention Research Institute Kyoto University Gokashyo Uji Kyoto Japan

Steel fiber reinforced cementitous composites （SFRCC） is a promising material with high strength in both compression and tension compared with normal concrete. The ductility is also greatly improved because of 6% volume portion of straight steel fibers. A steel beam-column connection with Steel fiber reinforced cementitous composites （SFRCC） slab diaphragms is proposed to overcome the damage caused by the weld. The push-out test results suggested that the application of SFRCC promises larger shear forces transferred through headed studs allocated in a small area in the slab. Finite element models were developed to simulate the behavior of headed studs. The failure mechanism of the grouped arrangement is fiarther discussed based on a series of parametric analysis. In the proposed connection, the SFRCC slab is designed as an exterior diaphragm to transfer the beam flange load to the column face. The headed studs are densely arranged on the beam flange to connect the SFRCC slab diaphragms and steel beams. The seismic performance and failure mechanism of the SFRCC slab diaphragm beam-column connection were investigated based on the cyclic loading test. Beam hinge mechanism was achieved at the end of the SFRCC slab diaphragm by using sufficient studs and appropriate rebars in the SFRCC slab.

关键词： multi-directional transmitting artificial boundary viscous-spring artificial boundary saturated soilfoundation Biot's equations

Reticulocyte hemoglobin content in the diagnosis of iron deficiency in Chinese pre-menopausal women

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Chinese Medical Journal 2007年第11期120卷 1010-1012页

作者： LUO Dan CHEN Yu WU Wei ZHANG feng XU Jia cui Wei LI Shu-lan LI Rong-sheng Department of Clinical Laboratory General Hospital of Air Force Beijing 100036 China Department of Clinical Laboratory Peking Union Medical College Hospital Chinese Academic of Medical Science ＆ Peking Union Medical College Beijing 100730 China Department of Hematology Peking Union Medical College Hospital Chinese Academic of Medical Science ＆ Peking Union Medical College Beijing 100730 China

Pre-menopausal women are at risk for iron deficiency due to menstrual blood losses. The prevalence rates （PR） of iron depletion, iron deficiency anemia （IDA）, and iron deficiency were 34.4%, 15.1% and 49.5% in pre-menopausal non-pregnant women respectively in China.1 Traditionally, the diagnosis of iron deficiency relies on the hematological markers （hemoglobin （HGB）, mean corpuscular volume （MCV）, mean corpuscular hemoglobin （MCH）, red cell distribution width （RDW）） and biochemical markers （serum ferritin （SF）, serum iron （SI）, transferrin saturation （TS）, total iron-binding capacity （TIBC））. Recently, the reticulocyte hemoglobin content （CHr） is considered to be used as a marker of iron deficiency.2 The aim of this study was to compare the diagnostic efficiency of CHr with the old markers in diagnosis of iron deficiency in Chinese pre-menopausal women.

关键词： reticulocyte iron deficiency iron deficiency anemia

Multi-objective optimization in quantum parameter estimation

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Science China(Physics,Mechanics & Astronomy) 2018年第4期61卷 30-35页

作者： BeiLi Gong Wei cui School of Automation Science and Engineering South China University of Technology

We investigate quantum parameter estimation based on linear and Kerr-type nonlinear controls in an open quantum system, and consider the dissipation rate as an unknown parameter. We show that while the precision of parameter estimation is improved,it usually introduces a significant deformation to the system state. Moreover, we propose a multi-objective model to optimize the two conflicting objectives:(1) maximizing the Fisher information, improving the parameter estimation precision, and(2)minimizing the deformation of the system state, which maintains its fidelity. Finally, simulations of a simplified ε-constrained model demonstrate the feasibility of the Hamiltonian control in improving the precision of the quantum parameter estimation.

关键词： quantum parameter estimation Fisher information multi-objective optimization

铜换热表面MgO颗粒与碳酸钙混合污垢沉积特性的分子动力学模拟

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中国电机工程学报 2024年第6期44卷 2310-2318,I0019页

作者：孙金泽崔晓松徐志明贾玉婷王景涛东北电力大学能源与动力工程学院吉林省吉林市132012

为探究MgO颗粒与碳酸钙混合污垢在换热表面沉积特性与机理,该文采用分子动力学模拟方法分析MgO颗粒和碳酸钙混合体系在铜换热表面的沉积过程,并通过改变碳酸钙浓度讨论浓度对混合污垢沉积特性的影响规律。结果表明,在混合污垢沉积过程中... 详细信息

为探究MgO颗粒与碳酸钙混合污垢在换热表面沉积特性与机理,该文采用分子动力学模拟方法分析MgO颗粒和碳酸钙混合体系在铜换热表面的沉积过程,并通过改变碳酸钙浓度讨论浓度对混合污垢沉积特性的影响规律。结果表明,在混合污垢沉积过程中,碳酸钙团簇在颗粒与换热表面间起到连接作用,形成稳固的沉积状态。此外,MgO颗粒对离子缔合形成团簇过程中的动力学特性和结构特性有所影响。随着碳酸钙浓度由0.26 mol/L升至1.1 mol/L,换热表面直接吸附的碳酸钙团簇数量变多,MgO颗粒更容易通过碳酸钙团簇的相互作用沉积在换热表面。MgO颗粒促进了碳酸钙的缔合过程,碳酸钙促进了混合团簇的沉积,进而形成初始沉积阶段的混合污垢。

关键词：碳酸钙 MgO颗粒铜换热表面混合污垢沉积特性分子动力学模拟

A Numerical Study on Pressure Drop in Microchannel Flow with Different Bionic Micro-Grooved Surfaces

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Journal of Bionic Engineering 2012年第1期9卷 99-109页

作者： Jing cui Yabo Fu School of Airport Civil Aviation University of China Tianjin 30300 P. R. China College of Physics and electronic engineering Taizhou University Taizhou 318000 P. R. China

The studies of bionics reveal that some aquatic animals and winged insects have developed an unsmoothed surface possessing good characteristics of drag reduction. In this paper, four types of bionic surfaces, placoid-shaped, V-shaped, rib- let-shaped, and ridge-shaped grooved surfaces, are employed as the microchannel surfaces for the purpose of reducing pressure loss. Lattice Boltzmann Method （LBM）, a new numerical approach on mescoscopic level, is used to conduct the numerical investigationsr. The results show that the micro-grooved surfaces possess the drag reduction performance. The existence of the vortices formed within the grooves not only decrease the shear force between fluid and wall but also minimize the contact area between fluid and walls, which can lead to a reduction of pressure loss. The drag reduction coefficient （η） for these four types of micro-structures could be generalized as follows： ηridge_shaped 〉 ηv-shaped 〉 ηplacoid-shaped 〉 ηriblet-shaped. Besides, the geometrical optimizations for the ridge-shaped grooves, which have the highest drag reduction performance, are performed as well. The results suggest that, for the purpose of drag reduction, the ridge-shaped grooves with smaller width to height ratio are recommended for the lower Reynolds number flow, while the ridge-shaped grooves with larger width to height ratio are be more suitable for the larger Reynolds number flow.

关键词： microchannel bionic grooves drag reduction lattice Boltzmann method