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石化技术与应用 2024年第4期42卷 306-313页

作者：易天立王琦桂薇华南理工大学环境与能源学院广东广州510006 黄河河口海岸科学研究院山东东营257091 连云港沃利工程技术有限公司上海分公司上海200000

综述了国内外催化裂解制低碳烯烃工艺的特点,阐述了催化裂解制低碳烯烃催化剂以及反应机理,指出开发多功能复合活性组元催化剂、创新催化裂解反应器型式、优化催化裂解工艺是未来催化裂解技术发展的3个方向。

关键词：催化裂解低碳烯烃轻油重油催化剂反应机理

Analysis of Non-uniform Mechanical Behavior for a Continuous Casting Mold Based on Heat Flux from Inverse Problem

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Journal of Iron and Steel Research International 2016年第2期23卷 83-91页

作者： Feng-ming DU Xu-dong WANG Yu liU tian-yi li Man YAO School of Materials Science and Engineering Dalian University of Technology

The distortion of mold plates plays an important role in the formation of surface cracks on continuously cast steel products. To investigate the non-uniform distortion of a mold, a full-scale stress model of the mold was de veloped. An inverse algorithm was applied to calculate the heat flux using the temperatures measured by the thermo- couples buried inside the mold plates. Based on this, a full-scale, finite-element stress model, including four copper plates, a nickel layer and water slots in different depths, was built to determine the complex mechanical behavior of the continuous casting mold used to produce steel slabs. The heat flux calculated by the inverse algorithm was applied to the stress model to analyze the non-uniform mechanical behavior. The results showed that the stress and distortion distributions of the four copper plates were not symmetrical, which reflected the non-uniform distortion behaviors of copper plates, water slots, nickel layer and the corner region of the mold. The gap between the mold and the slab was increased because of the corner distortion, which was very important for the heat transfer of initial solidifying shell, and it may be a major reason for the slow cooling of the slab corner.

关键词： finite-element stress model inverse algorithm nickel layer water slots continuous casting mold

Numerical modeling of flow in continuous bends from Daliushu to Shapotou in Yellow River

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Water Science and Engineering 2014年第2期7卷 194-207页

作者： He-fang JING Chun-guang li Ya-kun GUO li-jun ZHU yi-tian li School of Civil Engineering Beifang University of Nationalities School of Engineering University of Aberdeen School of Mathematics and Information Science Beifang University of Nationalities State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University

The upper reach of the Yellow River from Daliushu to Shapotou consists of five bends and has complex topography. A two-dimensional Re-Normalisation Group （RNG） k-ε model was developed to simulate the flow in the reach. In order to take the circulation currents in the bends into account, the momentum equations were improved by adding an additional source term. Comparison of the numerical simulation with field measurements indicates that the improved two-dimensional depth-averaged RNG k-e model can improve the accuracy of the numerical simulation. A rapid adaptive algorithm was constructed, which can automatically adjust Manning＇s roughness coefficient in different parts of the study river reach. As a result, not only can the trial computation time be significantly shortened, but the accuracy of the numerical simulation can also be greatly improved. Comparison of the simulated and measured water surface slopes for four typical cases shows that the longitudinal and transverse slopes of the water surface increase with the average velocity upstream. In addition, comparison was made between the positions of the talweg and the main streamline, which coincide for most of the study river reach. However, deviations between the positions of the talweg and the main streamline were found at the junction of two bends, at the position where the river width suddenly decreases or increases.

关键词： numerical simulation RNG k-e model Yellow River continuous bend circulationflow adaptive algorithm regarding Manning's roughness coefficient

Impact of water and sediment discharges on subaqueous delta evolution in Yangtze Estuary from 1950 to 2010

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Water Science and Engineering 2014年第3期7卷 331-343页

作者： Yun-ping YANG yi-tian li Yong-yang FAN Jun-hong ZHANG Key Laboratory of Engineering Sediment Tianjin Research Institute for Water Transport EngineeringMinistry of Transport State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University

In order to determine how the subaqueous delta evolution depends on the water and sediment processes in the Yangtze Estuary, the amounts of water and sediment discharged into the estuary were studied. The results show that, during the period from 1950 to 2010, there was no significant change in the annual water discharge, and the multi-annual mean water discharge increased in dry seasons and decreased in flood seasons. However, the annual sediment discharge and the multi-annual mean sediment discharge in flood and dry seasons took on a decreasing trend, and the intra-annual distribution of water and sediment discharges tended to be uniform. The evolution process from deposition to erosion occurred at the -10 m and -20 m isobaths of the subaqueous delta. The enhanced annual water and sediment discharges had a silting-up effect on the delta, and the effect of sediment was greater than that of water. Based on data analysis, empirical curves were built to present the relationships between the water and sediment discharges over a year or in dry and flood seasons and the erosion/deposition rates in typical regions of the suhaqueous delta, whose evolution followed the pattern of silting in flood seasons and scouring in dry seasons. Notably, the Three Gorges Dam has changed the distribution processes of water and sediment discharges, and the dam＇s regulating and reserving functions can benefit the subaqueous delta deposition when the annual water and sediment discharges are not affected.

关键词： water discharge sediment discharge, seasonal change delta Yangtze Estuary

Recent Advances in Carbon-Based Adsorbents for Adsorptive Separation of light Hydrocarbons

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Research 2022年第4期2022卷 261-281页

作者： Yong-Sheng Wang Xue-Jie Zhang Ya-Qi Ba tian-yi li Guang-Ping Hao An-Hui Lu State Key Laboratory of Fine Chemicals Liaoning Key Laboratory for Catalytic Conversion of Carbon ResourcesSchool of Chemical EngineeringDalian University of TechnologyDalian 116024China

light hydrocarbons(LHs)separation is an important process in petrochemical *** current separation technology predominantly relies on cryogenic distillation,which results in considerable energy *** separation using porous solids has received widespread attention due to its lower energy footprint and higher ***,tremendous efforts have been devoted to the design and synthesis of high-performance porous *** them,porous carbons display exceptional stability,tunable pore structure,and surface chemistry and thus represent a class of novel adsorbents upon achieving the matched pore structures for LHs *** this review,the modulation strategies toward advanced carbonbased adsorbents for LHs separation are firstly ***,the relationships between separation performances and key structural parameters of carbon adsorbents are discussed by exemplifying specific separation *** research findings on the control of the pore structures as well as the quantification of the adsorption sites are ***,the challenges of carbonaceous adsorbents facing for LHs separation are given,which would motivate us to rationally design more efficient absorbents and separation processes in future.

关键词： separation adsorbent porous

An analytical model of hot rolling force for a thick plate by combining globally optimal approximation yield criterion and egg-circular velocity field

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Journal of Iron and Steel Research International 2024年第3期31卷 647-659页

作者： Shun-hu Zhang yi Zhang Wen-hao tian Yan li Shagang School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

For the sake of solving the problem that it is difficult to be integrated for the Mises specific plastic power due to its nonlinearity,a new linear criterion,named the globally optimal approximation criterion,is constructed by the polygonal approximation to the Mises *** new criterion is proved to be the linear function of the principal stress componentsσ1,σ2 andσ3 and the trajectory of it on theπ-plane is a non-equiangular but equilateral dodecagon intersecting the Mises *** theoretical results of the current criterion described by the Lode stress parameters are in excellent accordance with the experimental ***,according to the trend that the metallic flow velocity between rollers aggrandizes gradually from the inlet to the outlet during the hot rolling of a thick plate,a biomimetic velocity field is proposed in which the horizontal velocity component fits the egg-circular curve *** velocity field and its simulated results agree quite ***,using the determined linear criterion,energy analysis of the constructed velocity field is utilized to obtain the interior deformation power,while the vector decomposition approach is utilized to obtain the frictional power and shear *** this basis,the overall power is obtained and the analytical solutions are generated for the rolling torque,rolling force and the coefficient of the stress state under different egg curves by minimizing the neutral ***,the parameter optimization of the characteristic parameterρwhich affects the slope of the egg-circular curve is carried out and the best egg-circular curve which can minimize the energy consumption is *** best agreement between the theoretical and observed values of rolling force and rolling torque is under this curve,and the mean relative errors of the rolling torque and rolling force are no more than 2.93%,while the maximum error is no more than 8.35%.

关键词： yield criterion Plastic deformation Rolling force Velocity field Analytical solution

Iridoids modulate inflammation in diabetic kidney disease: A review

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Journal of Integrative Medicine 2024年第3期22卷 210-222页

作者： Tong-yi Zhou Na tian liu li Rong Yu The First Clinical College of Chinese Medicine Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina Hunan Provincial Key Laboratory of Translational Research in Traditional Chinese Medicine Prescriptions and Zheng Changsha 410208Hunan ProvinceChina

In recent years,preclinical research on diabetic kidney disease (DKD) has surged to the forefront of scientific and clinical *** has become a pervasive complication of type 2 *** the complexity of its etiology and pathological mechanisms,current interventions,including drugs,dietary modifications,exercise,hypoglycemic treatments and lipid-lowering methods,often fall short in achieving desired therapeutic ***,primarily derived from the potent components of traditional herbs,have been the subject of long-standing *** data suggest that iridoids possess notable renal protective properties;however,there has been no summary of the research on their efficacy in the management and treatment of *** article consolidates findings from in vivo and in vitro research on iridoids in the context of DKD and highlights their shared anti-inflammatory activities in treating this ***,it explores how certain iridoid components modify their chemical structures through the regulation of intestinal flora,potentially bolstering their therapeutic *** review provides a focused examination of the mechanisms through which iridoids may prevent or treat DKD,offering valuable insights for future research endeavors.

关键词： Diabetic kidney disease Iridoids Gut-kidney axis Traditional Chinese medicine monomer Inflammation

Cyclometallated iridium phosphors with amino acid ancillary ligand for intracellular imaging

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Chinese Chemical Letters 2016年第10期27卷 1582-1585页

作者： tian-yi li Hua-Chao Chen yi-Ming Jing Hua-Bo Han Xiao liang You-Xuan Zheng Wei-jiang He State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced MicrostructuresSchool of Chemistry and Chemical EngineeringNanjing University

Two new iridium complexes, （dfppy）2Ir（L-alanine）（dfppy-2-（2,4-difluorophenyl）pyridine） and （piq）21r（L-alanine）（piq - 1-phenylisoquinoline） were prepared with L-alanine as ancillary ligand. The two complexes show bright greenish-blue and red emission respectively. Theoretic study demonstrated that the emission nature of these complexes is mainly determined by the main ligand. And their improved aqueous solubility and the retained quantum yield favor their application in cell imaging. Intracellular imaging suggested that these two complexes have fine cell membrane permeability and is mainly distributed in cytoplasm. This study displayed a new strategy to design aqueous soluble phosphorescent cyclometallated if（Ⅲ） complex via introducing amino acid as ancillary ligand.

关键词： Iridium complexL-AlanineWater solubilityPhosphorescent materialsCell imaging

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Virologica Sinica 2012年第3期27卷 165-171页

作者： Zheng Wang tian-yi li Jing-yun li li-li Chen Yong-jian liu Han-ping li Zuo-yi Bao Xiao-lin Wang Dao-min Zhuang Si-yang liu lin li Department of AIDS Research State Key Laboratory of Pathogen and BiosecurityBeo'ing Institute of Microbiology and EpidemiologyBeijing 100071China Urumqi General Hospital of Lanzhou Military Area Command Urumqi 830000China

Neutralizing antibodies are considered to be an important protective parameter used in HIV-1 vaccine evaluation. However, the exact role that neutralizing antibodies plays in controlling the disease progression of HIV-1 infected peoples is still undetermined. In this paper, we compared the protective function of the neutralizing antibody response in the plasma from LTNP and TP against clade B and clade C pseudoviruses. No difference in the neutralizing activities between the plasma from LTNP and TP was found, which was consistent with the most recent reports. In addition, no correlations between the titer or breadth and CD4+ or viral load in HIV-1 infected individuals were found. The protective roles played by neutralizing antibodies in controlling disease progression of HIV-1 infected people need to be considered in a new viewpoint.

关键词： HIV-1 Long term non-progressor (LTNP) Typical progressor (TP) Neutralization activity

Numerical study of the flow in the Yellow River with non-monotonous banks

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Journal of Hydrodynamics 2016年第1期28卷 142-152页

作者：景何仿李义天李春光 State Key Laboratory of Water Resources and Hydropower Engineering Sciences Wuhan University Research Institute of Numerical Computation and Engineering Applications North University for Nationalities

A 2-D depth averaged RNG k- ε model is developed to simulate the flow in a typical reach of the Upper Yellow River with non-monotonic banks. In order to take account of the effect of the secondary flow in a bend, the momentum equations are modified by adding an additional source term. A comparison between the numerical simulation and the field measurements indicates that the improved 2-D depth averaged RNG k- ε model can improve the accuracy of the numerical simulation. An arc spline interpolation method is developed to interpolate the non-monotonic river banks. The method can also be reasonably applied for the 2-D interpolation of the river bed level. Through a comparison of the water surface gradients simulated in the seven bends of the studied reach, some analytical formulae are improved to reasonably calculate the longitudinal and transverse gradients in meandering river reaches. Furthermore, the positions of the maximum water depth and the maximum velocity in a typical bend are discussed.

关键词： 2-D RNG k-ε model numerical simulation extra source term arc cubic spline interpolation non-monotonic bank