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Journal of Iron and Steel Research International 2024年第3期31卷 622-633页

作者： Pu Wang liang Chen Qun-wei Tang Wei-tao li Shao-xiang li Jia-quan Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Weifang Special Steel Group Co..Ltd. Weifang 262400ShandongChina School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

The propagation form of internal cracks induced by continuous casting soft reduction and the control strategy for enhancing the internal quality of 45 steel through industrial trials and a three-dimensional flow-heat transfer-solidification coupling model were *** results showed that the internal cracks induced by soft reduction exhibited a characteristic of being"coarse in the middle and fine at both ends",and displayed an elliptical arc distribution on the loose side of the strand cross *** cracks originated within the brittle temperature range and propagated inward to the liquid impenetrable temperature and outward to the zero ductility temperature or *** control strategy for enhancing the internal quality of the 45 steel strand through soft reduction is to adjust the casting speed or the reduction zone appropriately,ensuring that the central solid fraction of the reduction zone falls within the range of *** this point,a reasonable reduction amount is allocated to eliminate the center shrinkage cavities and center segregation,even if it results in minor reduction-induced cracks.

关键词： Continuous casting Soft reduction Crack propagation Internal quality Control strategy

Synthesis of Coumarin-functionalized Calix[4]arene and Selective Recognition for L-Tryptophan

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Chinese Chemical Letters 2006年第5期17卷 575-577页

作者： Jian quan LU li ZHANG Ting quan SUN Gui xiang WANG ling Yan WU Hubei Key Laboratory of Bioanalytical Technique Hubei Normal University Huangshi 435002

5,11,17,23-Tetra-tert-butyl-25, 27-bis（7＇-methoxycoumarin-3＇-methyloxy）-26, 28-dihydroxycalix[4]arene was synthesized and characterized. The derivative could recognize L-tryptophan with a 1：1 complexing ratio and an apparent equilibrium constant of 111 L mol^-1 in DMF acetonitrile as solvent by UV-visible and fluorescent spectrophotometry.

关键词： Calixarene synthesis recognition L-tryptophan.

基于干细胞因子/C-kit信号通路探讨鼠李糖乳酪杆菌Glory LG12的润肠通便作用

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食品科学 2025年第3期46卷 20-26页

作者：项芳琴李玉星李柏良东北农业大学食品学院黑龙江哈尔滨150006

目的:基于干细胞因子(stem cell factor,SCF)/C-kit信号通路探讨鼠李糖乳酪杆菌Glory LG12的润肠通便作用。方法:雄性ICR小鼠随机分为空白组、模型组以及鼠李糖乳酪杆菌Glory LG12低剂量(1.5×10^(6)CFU/只)、中剂量(1.5×10^(7)CFU/只... 详细信息

目的:基于干细胞因子(stem cell factor,SCF)/C-kit信号通路探讨鼠李糖乳酪杆菌Glory LG12的润肠通便作用。方法:雄性ICR小鼠随机分为空白组、模型组以及鼠李糖乳酪杆菌Glory LG12低剂量(1.5×10^(6)CFU/只)、中剂量(1.5×10^(7)CFU/只)和高剂量(1.5×10^(8)CFU/只)组,各组小鼠分别连续灌胃相应的药物15 d后,灌胃盐酸洛哌丁胺混悬液(4 mg/kg)建立便秘模型,测定各组小鼠的体质量、首粒黑便排出时间、5 h内黑便排出数量及质量、小肠推进率、血清中胃肠调节肽和炎性细胞因子水平及小鼠结肠组织SCF、C-kit转录水平,并观察结肠病理结构。结果:与模型组相比,中、高剂量的鼠李糖乳酪杆菌Glory LG12均能缩短小鼠的首粒黑便排出时间(P<0.001),增加小鼠5 h内排黑便的粒数和质量(P<0.01、P<0.001),提高小肠内的墨汁推进率(P<0.001);升高小鼠血清中胃动素、胃泌素、P物质和白细胞介素(interleukin,IL)10的质量浓度,降低内皮素1、生长抑素、血管活性肠肽和IL-6的质量浓度;增加结肠组织中SCF和C-kit mRNA相对表达量(P<0.01、P<0.001);修复受损结肠屏障。结论:鼠李糖乳酪杆菌Glory LG12能够通过调节SCF/C-kit通路,进而影响胃肠调节肽和炎性细胞因子的释放,发挥其促进胃肠蠕动的功能,改善便秘症状。

关键词：鼠李糖乳酪杆菌Glory LG12 便秘润肠通便效果炎性细胞因子胃肠调节肽干细胞因子/C-kit信号通路

Design and Analysis of a V-Shaped Permanent Magnet Vernier Motor for High Torque Density

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CES Transactions on Electrical Machines and Systems 2022年第1期6卷 20-28页

作者： Zixuan xiang Weiling Pu Xiaoyong Zhu li quan IEEE School of Electrical and Information Engineering Jiangsu UniversityZhenjiang 212013China

This paper proposes a V-shaped permanent magnet vernier(V-PMV)motor for potential applications in direct drive *** designing suitable pole slot ratio and adopting the V-shaped PM topology and dummy slots in rotor,the flux leakage can be avoided ***,the high-order harmonics with large amplitude in the airgap magnetic field are fully utilized and served as the effective working harmonics,which aim at enhancing the output torque and reducing the torque ***,to extensively explore the performance advantages of the V-PMV motor,a multi-objective optimization study is carried ***,the electromagnetic performances of the V-PMV motors are analyzed and compared in ***,a prototype machine is built and *** theoretical analysis and experimental results verify the validity of the motor and multi-objective optimization design approach.

关键词： Flux modulation motor PM Vernier motor PM utilization Working harmonics Optimization design

Fe-Nx Sites enriched microporous carbon nanoflower planted with tangled bamboo-like carbon nanotube as a strong polysulfides anchor for lithium-sulfur batteries

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Green Energy & Environment 2021年第4期6卷 506-516页

作者： Hongtai li Yanxiao Chen quan Jin Wei xiang Benhe Zhong Xiaodong Guo Bao Wang School of Chemical Engineering Sichuan UniversityChengdu 610065China State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China College of Materials and Chemistry&Chemical Engineering Chengdu University of TechnologyChengdu 610059China

Serious shuttle effect and sluggish conversion kinetics of lithium polysulfides(liPSs)have a massive impact on obstructing the practical application of lithium-sulfur(li-S)*** address such issues,Fe-Nx sites enriched microporous nanoflowers planted with tangled bamboo-like carbon nanotubes(Fe-Nx-C/Fe_(3)C-CNTs NFs)are found to be effective catalytic mediators with strong anchoring capabilities for *** bamboo-like carbon nanotubes catalyzed by Fe_(3)C/Fe entangled each other to form a conductive network,which encloses a flowerlike microporous carbon core with embedded well-dispersed Fe-Nx active *** expected,electrons smoothly transfer along the dense conductive bamboo-like carbon network while the flower-like carbon core consisting of micropores induces the homogeneous distribution of tiny sulfur and favors the lithium ions migration with all ***,Fe-Nx sites strongly trap long-chain liPSs with chemical anchoring,and catalyze the redox conversion of *** to the aforementioned synergistic effects,the S@Fe-Nx-C/Fe_(3)C-CNTs NFs cathode exhibited a remarkable specific capacity(635 mAh g_(s)^(-1))at 3 C and a favorable capacity decay with 0.04%per cycle even after 400 cycles at 1 C.

关键词： li-S batteries ZIFs One-pot Heterostructure Cathode

Abnormalities Occurring during Female Gametophyte Development Result in the Diversity of Abnormal Embryo Sacs and Leads to Abnormal Fertilization in indica/japonica Hybrids in Rice

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Journal of Integrative Plant Biology 2009年第1期51卷 3-12页

作者： Yu-xiang Zeng Chao-Yue Hu Yong-Gen Lu Jin-quan li xiang-Dong liu ( Guangdong Provincial Key Laboratory of Plant Molecular Breeding South China Agricultural University Guangzhou 510642 China)

Embryo sac abortion is one of the major reasons for sterility in indicaljaponica hybrids in rice. To clarify the causal mechanism of embryo sac abortion, we studied the female gametophyte development in two indicaljaponica hybrids via an eosin B staining procedure for embryo sac scanning using confocal laser scanning microscope. Different types of abnormalities occurred during megasporogenesis and megagametogenesis were demonstrated. The earliest abnormality was observed in the megasporocyte. A lot of the chalazal-most megaspores were degenerated before the mono-nucleate embryo sac stage. Disordered positioning of nucleus and abnormal nucellus tissue were characteristics of the abnormal female gametes from the mono-nucleate to four-nucleate embryo sac stages. The abnormalities that occurred from the early stage of the eight-nucleate embryo sac development to the mature embryo sac stage were characterized by smaller sizes and wrinkled antipodals. Asynchronous nuclear migration, abnormal positioning of nucleus, and degeneration of egg apparatus were also found at the eight-nucleate embryo sac stage. The abnormalities that occurred during female gametophyte development resulted in five major types of abnormal embryo sacs. These abnormal embryo sacs led to abnormal fertilization. Hand pollination using normal pollens on the spikelets during anthesis showed that normal pollens could not exclude the effect of abnormal embryo sac on seed setting.

关键词： indicaljaponica hybrid megagametogenesis megasporogenesis Oryza sativa whole-mount eosin B-staining confocal laser scanning microscopy.

Airgap-harmonic-oriented Partitioned Design Method of PMV Motor with Improved Torque Performances

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CES Transactions on Electrical Machines and Systems 2024年第1期8卷 43-50页

作者： Zhaopeng Wu li quan Zixuan xiang Deyang Fan Tengguang Wang Xiaoyong Zhu the School of Electrical and Information Engineering Jiangsu UniversityZhenjiang 212013China IEEE

Here,we introduce a partitioned design method that is oriented toward airgap harmonic for permanent magnet vernier(PMV)*** method proposes the utilization of airgap flux harmonics as an effective bridge between the torque design region and the torque *** illustrate the efficacy of this method,a partitioned design PMV motor is presented and compared with the initial ***,the torque design region of the rotor is artfully divided into the torque enhancement region and ripple reduction ***,the main harmonics that generate output torque are chosen and enhanced,***,the harmonics that generate torque ripple are selected and reduced based on torque harmonics ***,the functions of the partitioned PMV motor torque are assessed based on the finite element *** the purposeful design of these two regions,the output torque is strengthened while torque ripple is inhibited effectively,verifying the effectiveness and reasonability of the proposed design method.

关键词： Permanent magnet vernier(PMV)motor Airgap flux harmonic Partitioned design Low torque ripple

Spillover of international crude oil prices on China's refined oil wholesale prices and price forecasting:Daily-frequency data of private enterprises and local refineries

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Petroleum Science 2022年第3期19卷 1433-1442页

作者： Xun-Zhang Pan Xi-Ran Ma li-Ning Wang Ya-Chen Lu Jia-quan Dai xiang li School of Economics and Management China University of PetroleumBeijing 102249China Economics&Technology Research Institute China National Petroleum CorporationBeijing 100724China Key Laboratory of Oil and Gas Market Simulation and Price Forecasting China National Petroleum CorporationBeijing 100724China Institue of Energy Peking UniversityBeijing 100080China

Compared with retail prices of state-owned companies used in almost all existing studies,China’s refined oil wholesale prices of private enterprises and local refineries are more affected by the market and better reflect the real supply-demand *** the first time,this paper applies own-monitored dailyfrequency wholesale prices of China’s private enterprises and local refineries during 2013-2020 to derive spillover effects of international crude oil prices on China’s refined oil prices through the VAR-BEKKGARCH(vector autoregression-Baba,Engle,Kraft,and Kroner-generalized autoregressive conditional heteroscedasticity)model,and then tries to forecast wholesale prices through the PCA-BP(principal component analysis-back propagation)neural network *** show that international crude oil prices have significant mean spillover and volatility spillover effects on China’s refined oil wholesale *** in crude oil prices are the Granger cause of changes in refined oil wholesale *** the improvement of China’s oil-pricing mechanism in 2016,the volatility spillover from the international crude oil market to China’s refined oil market gradually increases,and the BRENT price variation has an increasing impact on the refined oil wholesale price *** PCA-BP model could serve as a candidate tool for forecasting China’s refined oil wholesale prices.

关键词： Own-monitored daily-frequency data Refined oil wholesale prices Spillover effects VAR-BEKK-GARCH PCA-BP neural Network

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苯乙烯中硫醇类含硫化合物的脱除研究

现代化工 2025年第1期45卷 87-92页

作者：孙公全尚森森赵卿波李晓盼刁晶晶吕小军李翔天津科技大学化工与材料学院天津300457 新疆天利石化股份有限公司新疆克拉玛依833699

以氢氧化钠、甲醇钠、乙醇钠和叔丁醇钾等固体碱以及AlCl_(3)、FeCl_(3)、ZnCl_(2)和CuCl_(2)等固体Lewis酸作催化剂,以摩尔分数为1%的己硫醇/苯乙烯溶液作模型油品,研究了硫醇在这些固体酸碱上的反应。结果表明,甲醇钠和乙醇钠以及FeCl... 详细信息

以氢氧化钠、甲醇钠、乙醇钠和叔丁醇钾等固体碱以及AlCl_(3)、FeCl_(3)、ZnCl_(2)和CuCl_(2)等固体Lewis酸作催化剂,以摩尔分数为1%的己硫醇/苯乙烯溶液作模型油品,研究了硫醇在这些固体酸碱上的反应。结果表明,甲醇钠和乙醇钠以及FeCl_(3)能够在室温下高活性地催化苯乙烯中少量己硫醇转化为二己基二硫醚和1-苯乙基己硫烷等大分子高沸点的含硫化合物,并可以通过后续精馏从苯乙烯中分离,为苯乙烯反应脱除硫醇硫提供了可行的方法。固体碱只催化了己硫醇的氧化反应,其活性与碱性和结构都有关,具有较强碱性和较小空间位阻的甲醇钠和乙醇钠表现出最佳的催化性能。FeCl_(3)既催化了己硫醇的氧化反应,也催化了己硫醇与苯乙烯的加成反应;CuCl_(2)也表现出很高的催化己硫醇氧化的活性,起到反应物或氧化剂的作用,可将己硫醇氧化成二己基二硫醚,同时释放出HCl,与苯乙烯反应生成1-氯-1-苯乙烷。

关键词：苯乙烯硫醇反应脱硫固体碱路易斯酸

Residual Curvature of Longitudinal Profile Plate Roller in Leveling Process

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Journal of Iron and Steel Research International 2013年第10期20卷 23-27页

作者： CUI li SHI quan-qiang liU xiang-hua HU Xian-lei Aviation Industry Corporation of China Shenyang Aircraft Corporation Institute of Metal Research Chinese Academy of Sciences State Key Laboratory of Rolling and Automation Northeastern University

Roller leveling process of longitudinal profile （LP） plate is hardly studied because plate thickness changes. Deformation characteristics and residual curvature during LP plate leveling process were investigated based on curva ture integral by elastic plastic differences. It was found that entry intermesh section is reduced with increasing thick- ness and entry intermesh should be from 0.7 to 1.1 mm for LP plate with 42/54 mm in thickness. In order to get satisfactory flatness along longitudinal direction, small entry intermesh should be selected and exit intermesh should be 0 ram. In addition, thickness section for I.P plate which can be leveled by 11 roller leveler is from 24 to 60 mm. Finally, there is an intermesh schedule that could level LP plate with initial curvature less than elastic limit curvature.

关键词： roller leveling LP plate intermesh residual curvature residual stress