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Journal of Iron and Steel Research International 2005年第5期12卷 20-27页

作者： ZHANGLi-feng zhijian-jun MOUJi-ning CUIJian UniversityofIllinoisatUrbana-Champaign UrbanaIL61801USA BaoshanIronandSteelCo Shanghai201900China

The κ-ε two-equation model is used to simulate the fluid flow in the continuous casting tundish coupling with the effect of thermal buoyancy. The natural convection induced by the thermal buoyancy generates an upward flow pattern especially at the outlet zone, and has little effect on the fluid flow in the inlet zone. The maximum viscosity is 700 times larger than the laminar viscosity, which indicates the strong turbulent flow in the tundish. The maximum temperature difference in the whole tundish is 82 K. The temperature near the stopper rod and the short wall is obviously lower than that in the inlet zone. The existence of the stopper rod has a big effect on the fluid flow entering the SEN and the mold. All the characteristics of the tundish geometry should be considered to accurately simulate the fluid flow in the tundish.

关键词： thermal buoyancy fluid flow tundish inclusion stopper rod temperature

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The early risk stratification of the patients with acute chest pain

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Journal of Nanjing Medical University 2007年第6期21卷 363-366页

作者： Chunping Tang Yanrong Liu Qin Shen zhijian Yang jun Huang Ming Gui Chest Pain Emergency Department the First Affiliated Hospital of Nanjing Medical University＇ Nanjing 210029 Jiangsu Province China

Objective： This investigation was designed to stratify patients with acute chest pain based on their symptoms, electrocardiogram （ECG）, cardiac injury markers and the number of accompanying traditional risk factors（smoking, obesity, hyperlipemia, hypertension, diabetes）, and to assess the effect of the above factors to obtain a risk stratification for patients with chest pain. Methods： We identified 139 patients with acute chest pain, including 45 myocardiac infarction patients, 65 unstable angina patients and 29 chest pain patients without identified acute coronary syndrome（ACS） admitted to our Coronary Heart Center during December 2004 to February 2005. All patients accepted coronary angiography. All data was collected using questionnaires. Based on reported symptom, electrocardiogram （ECG）, cardiac injury markers and the number of the accompanying traditional risk factors, we stratified all patients into four groups： Group 1, patients with acute chest pain, ECG changes and abnormal cardiac injury biomarkers. Group 2, patients with acute chest pain and ECG changes（without abnormal cardiac injury biomarkers）. Group 3, patients with acute chest pain, normal ECG, normal cardiac injury biomarkers and 〉2 traditional risk factors. Group 4, patients with acute chest pain, normal ECG and normal cardiac injury biomarkers, but only ≤ 2 traditional risk factors. From this data we examined the difference of ACS incidence in the four groups. Results：After stratification the ACS incidence of the grouped patients in turn was 100%, 84%, 69.6% and 53.3%. The combination of early phase ECG and cardiac injury markers identified 70.9% patients with ACS（the specificity being 90.7%）. The mortality of group 3 was higher compared with group 4（69.6% vs 53.3%）, however the P value was more than 0.05 and didn＇ t show significant statistical difference. The correlation analysis found the number of the traditional risk factors had a significant positive correlation （r= 0.202, P = 0.044） with

关键词： acute chest pain risk stratification ECG cardiac injury markers

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基于改进蜣螂算法的电动汽车有序充电研究

现代电子技术 2025年第2期48卷 115-123页

作者：杜志坚廖道争程俊席磊三峡大学电气与新能源学院湖北宜昌443002 千乘研究院北京101111

为了解决大规模的电动汽车无序充电给电网带来的压力,提出一种改进蜣螂算法(LBDBO)的电动汽车有序充电方法。首先,建立一个以电网负荷峰谷差和用户费用最小化的目标函数;其次,针对传统蜣螂算法存在的收敛精度不足和易陷入局部最优解的问... 详细信息

为了解决大规模的电动汽车无序充电给电网带来的压力,提出一种改进蜣螂算法(LBDBO)的电动汽车有序充电方法。首先,建立一个以电网负荷峰谷差和用户费用最小化的目标函数;其次,针对传统蜣螂算法存在的收敛精度不足和易陷入局部最优解的问题,利用Logistic混沌映射对种群进行初始化,使蜣螂群体分布更均匀;然后,引入鱼鹰优化算法、透镜成像反向学习策略和局部搜索策略来更新蜣螂的位置,避免在迭代过程中陷入局部最优,同时提高寻优精度;最后,通过与标准蜣螂算法(DBO)、灰狼优化算法(GWO)、北方苍鹰优化算法(NGO)、鲸鱼优化算法(WOA)和基于减法平均的优化器算法(SABO)在基准测试函数中进行性能评估对比,验证策略改进的有效性。将LBDBO算法应用于电动汽车有序充电问题求解上,结果表明,改进算法可以显著降低峰谷差和充电成本,进一步验证了该算法的优越性和实用性。

关键词：电动汽车有序充电改进蜣螂算法 Logistic混沌映射电网负荷充电费用

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红花逍遥片治疗月经量少72例临床观察

中国民族民间医药 2017年第5期26卷 124-127页

作者：裴素娟邓智建杨君张强新乡医学院第一附属医院河南卫辉453100

目的:观察红花逍遥片治疗肝郁气滞血瘀型月经量少的疗效。方法:选取151例月经量少的患者为受试者,随机分成对照组38例、安慰剂组38例和试验组75例,3组分别给予女金片、红花逍遥片模拟剂和红花逍遥片口服治疗,疗程8周。比较3组治疗前后... 详细信息

目的:观察红花逍遥片治疗肝郁气滞血瘀型月经量少的疗效。方法:选取151例月经量少的患者为受试者,随机分成对照组38例、安慰剂组38例和试验组75例,3组分别给予女金片、红花逍遥片模拟剂和红花逍遥片口服治疗,疗程8周。比较3组治疗前后月经失血图总分变化、中医证候疗效、各单项症状疗效和不良反应情况。结果:治疗8周后,主要疗效月经失血图积分治疗前后增加值:试验组与对照组、安慰剂组比较差异均有统计学意义(P<0.05);次要疗效(中医证候疗效总有效率、中医症状总积分下降值、除经前乳胀外的中医各单项症状疗效)方面,3组比较差异均有统计学意义(P<0.05);治疗期间3组未发现不良事件。结论:红花逍遥片治疗肝郁气滞血瘀型月经量少安全有效。

关键词：月经量少肝郁气滞血瘀型红花逍遥片

Improved Staggered Algorithm for Phase-Field Brittle Fracture with the Local Arc-Length Method

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Computer Modeling in Engineering & Sciences 2023年第1期134卷 611-636页

作者： zhijian Wu Li Guo jun Hong Jiangsu Key Laboratory of Engineering Mechanics Department of Engineering MechanicsSchool of Civil EngineeringSoutheast UniversityNanjing214135China

The local arc-length method is employed to control the incremental loading procedure for phase-field brittle fracture *** improved staggered algorithm with energy and damage iterative tolerance convergence criteria is developed based on the residuals of displacement and *** improved staggered solution scheme is implemented in the commercial software ABAQUS with user-defined element *** layered system of finite elements is utilized to solve the coupled elastic displacement and phase-field fracture problem.A one-element benchmark test compared with the analytical solution was conducted to validate the feasibility and accuracy of the developed *** study shows that the result calculated with the developed method does not depend on the selected size of loading *** results of several numerical experiments show that the improved staggered algorithm is efficient for solving the more complex brittle fracture problems.

关键词： Phase-field model brittle fracture crack propagation ABAQUS subroutine staggered algorithm

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佐剂性关节炎大鼠模型的实验研究

天津药学 2004年第2期16卷 1-4页

作者：冯芳丁志建刘俊浙江养生堂天然药物研究所杭州310007

目的 :改进大鼠佐剂性关节炎 ( AA)模型制作的实验设计 ,提高造模成功率。方法 :选择影响造模成功率较大的因素 ,如弗氏完全佐剂 ( FCA)中的卡介苗 ( BCG)浓度、FCA注射量、FCA体内注射部位作为研究对象。结果 :不同 BCG浓度下的最高成... 详细信息

目的 :改进大鼠佐剂性关节炎 ( AA)模型制作的实验设计 ,提高造模成功率。方法 :选择影响造模成功率较大的因素 ,如弗氏完全佐剂 ( FCA)中的卡介苗 ( BCG)浓度、FCA注射量、FCA体内注射部位作为研究对象。结果 :不同 BCG浓度下的最高成功率为 78.5 % ;不同注射量最高成功率为 71.9% ;不同注射部位最高成功率为 70 .0 %。结论 :用含 2 0mg/ ml BCG浓度的 FCA 0 .1ml注射量 ,后肢足跖皮内注射能明显提高 AA大鼠造模的成功率。较以前文献报道的含 10mg/ ml BCG浓度的 FCA 0 .0 5 ml注射量 ,背部多点注射法等有较大的改进。

关键词：卡介苗(BCG) 弗氏不完全佐剂(FIA) 弗氏完全佐剂(FCA) 佐剂性关节炎(AA) 类风湿性关节炎(RA)

Adsorption Performance of Sliding Wall-Climbing Robot

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Chinese Journal of Mechanical Engineering 2010年第6期23卷 733-741页

作者： LI jun GAO Xueshan FAN Ningjun LI Kejie JIANG Zhihong JIANG zhijian School of Mechatronical Engineering Beijing Institute of Technology Beijing 100081 China School of Electric and Information Engineering Beijing University of Civil Engineering and Architecture Beo＇ing 100044 China

Sliding wall-climbing robot （SWCR） is applied worldwide for its continuous motion, however, considerable air leakage causes two problems： great power consumption and big noise, and they constraint the robot＇s comprehensive performance. So far, effective theoretical model is still lacked to solve the problems. The concept of SWCR＇s adsorption performance is presented, and the techniques of improving utilization rate of given adsorption force and utilization rate of power are studied respectively to improve SWCR＇s adsorption performance. The effect of locomotion mechanism selection and seal＇s pressure allocation upon utilization rate of given adsorption force is discussed, and the theoretical way for relevant parameters optimization are provided. The directions for improving utilization rate of power are pointed out based on the detail analysis results of suction system＇s thermodynamics and hydrodynamics. On this condition, a design method for SWCR-specific impeller is presented, which shows how the impeller＇s key parameters impact its aerodynamic performance with the aid of computational fluid dynamics （CFD） simulations. The robot prototype, BIT Climber, is developed, and its functions such as mobility, adaptability on wall surface, payload, obstacle ability and wall surface inspection are tested. Through the experiments for the adhesion performance of the robot adsorption system on the normal wall surface, at the impeller＇s rated rotating speed, the total adsorption force can reach 237.2 N, the average effective negative pressure is 3.02 kPa and the design error is 3.8% only, which indicates a high efficiency. Furthermore, it is found that the robot suction system＇s static pressure efficiency reaches 84% and utilization rate of adsorption force 81% by the experiment. This thermodynamics model and SWCR-specific impeller design method can effectively improve SWCR＇s adsorption performance and expand this robot applicability on the various walls. A sliding wall-climbing

关键词： wall-climbing robot adsorption performance centrifugal impeller CFD simulation

Removal of fluoride from water using titanium-based adsorbents

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Frontiers of Environmental Science & Engineering 2010年第4期4卷 414-420页

作者： zhijian LI Shubo DENG Xueying ZHANG Wei ZHOU jun HUANG Gang YU Department of Environmental Science and Engineering POPs Research CenterTsinghua UniversityBeijing 100084China

Three adsorbents including TiO_(2),Ti-Ce,and Ti-La hybrid oxides were prepared to remove fluoride from aqueous *** Ti-Ce and Ti-La hybrid adsorbents obtained by the hydrolysis-precipitation method had much higher sorption capacity for fluoride than the TiO_(2) adsorbent prepared through *** earth(Ce and La)oxides and TiO_(2) exhibited a synergistic effect in the hybrid adsorbents for fluoride *** sorption equilibrium of fluoride on the three adsorbents was achieved within 4 h,and the pseudo-second-order model described the sorption kinetics *** sorption isotherms fitted the Langmuir model well,and the adsorption capacities of fluoride on the Ti-Ce and Ti-La adsorbents were about 9.6 and 15.1 mg·g^(-1),respectively,at the equilibrium fluoride concentration of 1.0 mg·L^(-1),much higher than the 1.7 mg·g^(-1) on the TiO_(2).The sorption capacities of fluoride on the three adsorbents decreased significantly when the solution pH increased from 3 to *** electrostatic interaction played an important role in fluoride removal by the three adsorbents,and Fourier transform infrared(FTIR)analysis indicated that the hydroxyl groups on the adsorbent surface were involved in fluoride adsorption.

关键词： fluoride adsorption titanium dioxide titanium-based adsorbent sorption mechanism

Boron separation by adsorption and flotation with Mg-Al-LDHs and SDBS from aqueous solution

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Chinese Journal of Chemical Engineering 2023年第9期61卷 192-200页

作者： Chun Bai Huifang Zhang Qinglong Luo Xiushen Ye Haining Liu Quan Li jun Li zhijian Wu School of Chemical Engineering Qinghai UniversityXining 810016China Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt LakesChinese Academy of SciencesXining 810008China Key Laboratory of Salt Lake Resources Chemistry of Qinghai Province Xining 810008China

Layered double hydroxides(LDHs)have been shown to be effective adsorbents for ***,solid-liquid separation is still a problem when separating boron from industrial radioactive waste *** this research,three types of Mg-Al-LDHs including Mg-Al-LDH(NO_(3)^(-)),Mg-Al-LDH(Cl^(-))and Mg-Al-LDH(SO_(4)^(2-))were applied to adsorb boron,and moreover sodium dodecylbenzenesulfonate(SDBS)was used to float the LDH particles from aqueous solution after boron *** results showed that 60 min was sufficient for the equilibrium adsorption of the three *** boron adsorption capacity of three LDHs was determined as follows:Mg-Al-LDH(NO_(3)^(-))>Mg-Al-LDH(Cl^(-))>Mg-Al-LDH(SO_(4)^(2-)),and was 2.0,0.98 and 0.2 mmol·g^(-1),each ranging from 0 to 80 mmol·L^(-1)with the initial boron *** efficiency of boron removal by Mg-Al-LDH(NO_(3)^(-))and SDBS can reach up to 89.7%.Furthermore,the boron flotation mechanism of SDBS and LDHs has been studied,since SDBS as a flotation agent can react with LDHs and penetrate into the interlayer of LDHs in addition to electrostatic ***,LDHs in solution can be floated onto the foam layer to be separated from the solution,and the clarified solution was *** method is simple and promising for boron removal from aqueous solution.

关键词： Boron Separation Adsorption Flotation Layered double hydroxide Sodium dodecyl benzene sulfonate

Effects of Overwintering on the Survival and Vector Competence of Aedes albopictus in the Urban Life Cycle of Dengue Virus in Guangzhou,China

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Virologica Sinica 2021年第4期36卷 755-761页

作者： Yue Chen Ronghua Chen Jianrong Gao Chunyuan Li jun Liu zhijian Zhou Ruiwen Ren Center for Disease Prevention and Control of the Southern Theatre Command of the PLA Guangzhou510507China Guangdong Arbovirus Diseases Emergency Technology Research Center Guangzhou510507China

The Pearl River Delta,where Aedes albopictus(***)is the only vector for dengue transmission,has exhibited one of the highest dengue burdens in southern China in recent ***,whether dengue virus(DENV)can overwinter in *** in the Pearl River Delta has not been determined to *** this study,300 field-derived *** mosquitoes from Guangzhou that were infected with the predominant endemic DENV-1 strain were investigated under simulated urban balcony environment from October 16,2016,to june 16,*** vertical transmission of DENV in the infected overwintering *** was *** DENV infected overwintering mosquitoes were evaluated for viral load at nine-time points using reverse transcription-quantitative *** vector competence of the infected overwintering *** was also investigated by using suckling *** mosquitoes and larvae were found during the observation *** vertical transmission of DENV-1 was *** DENV-1-positive rates between overwintering males and females had no *** proportion of DENV-1-positive overwintering mosquitoes decreased over time and had no difference beyond three months after the *** mosquitoes can spread DENV-1 to *** engorged mosquitoes at an ambient temperature below 15℃were *** ratio of engorged mosquitoes was positively correlated with the ambient temperature ranging from 15 to 30℃.Our results demonstrated that DENV can overwinter in *** in the Pearl River Delta,*** is the competent vector for DENV,and maintain autochthonous dengue outbreaks in the Pearl River Delta through vertical transmission.

关键词： Dengue virus(DENV) Aedes albopictus Overwintering Vertical transmission Subtropical region