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Structural Optimization of Electromagnetic Swirling Flow in Nozzle of Slab Continuous Casting

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Acta Metallurgica Sinica(English Letters) 2018年第12期31卷 1317-1326页

作者： xiao-Wei Zhu De-Wei Li Chun-Lei Wu Katsukiyo Marukawa qiang Wang Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern University School of Metallurgy Northeastern University School of Resources and Materials Northeastern University at Qinhuangdao

During the slab continuous casting process, the flow field of molten steel in the mold plays a decisive role in the quality ofthe slab. In this paper, electromagnetic swirling flow in nozzle technology is proposed to control the flow field in *** technology can drive molten steel to rotate inside the submerged entry nozzle by electromagnetic force, therebycontrolling the flow field. This research shows that it can reduce the impact of molten steel on the bottom of nozzle andpartly reduce the negative pressure at the upper part of nozzle outlet which is even eliminated by optimizing the structureand angle of nozzle. The area of heat flux of the mold wall becomes larger, and the crest value of heat flux gets lower thanthat without swirling in nozzle and any nozzle optimization. The meniscus fluctuates smoothly, and the flow velocity at thetop surface is within a reasonable range. The temperature field distribution in the mold is uniform which was beneficial tothe growth of equiaxed crystal and decreased element segregation.

关键词： Continuous casting Submerged entry nozzle Electromagnetic swirling flow Slab Numerical simulation

京津冀协同发展背景下河北高等职业院校高质量发展路径探析

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承德石油高等专科学校学报 2024年第4期26卷 1-4,16页

作者：秘密赵晓强刘少楷河北石油职业技术大学马克思主义学院河北承德067000 河北石油职业技术大学热能工程系河北承德067000 河北石油职业技术大学管理工程系河北承德067000

京津冀地区是我国经济最有活力、开放程度较高、创新能力最强、吸纳人口最多的地区之一,是拉动我国经济的重要引擎。在京津冀协同发展不断迈上新台阶,努力成为中国式现代化建设的先行区、示范区背景下,职业教育的协同为推动京津冀各方... 详细信息

京津冀地区是我国经济最有活力、开放程度较高、创新能力最强、吸纳人口最多的地区之一,是拉动我国经济的重要引擎。在京津冀协同发展不断迈上新台阶,努力成为中国式现代化建设的先行区、示范区背景下,职业教育的协同为推动京津冀各方面发展实施一定支持。现阶段河北职业院校仍存在内生动力缺失、合作范围小等实际问题,为实现河北高等职业院校高质量发展,更好参与京津冀协同发展,应从底层设计、专业布局及师资共享几方面来进行实践探索。

关键词：京津冀协同发展职业教育高等职业教育

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人民警察使用武器条件之厘定

河北公安警察职业学院学报 2024年第1期24卷 62-65,69页

作者：陈玉强蓝永琪重庆警察学院重庆401331

传统观点认为人民警察使用武器应具备四个条件,即判明情况、暴力犯罪行为正在发生、情形紧急、经警告无效,该“四要件说”存在逻辑混乱、判明标准内容不全及标准不清、暴力犯罪外延过大、正在发生以偏概全、对情形紧急定性不准等诸多问... 详细信息

传统观点认为人民警察使用武器应具备四个条件,即判明情况、暴力犯罪行为正在发生、情形紧急、经警告无效,该“四要件说”存在逻辑混乱、判明标准内容不全及标准不清、暴力犯罪外延过大、正在发生以偏概全、对情形紧急定性不准等诸多问题。首先,把判明情况和警告无效作为使用武器的实体和程序两大条件;其次,从三个维度细化“判明情况”内容,即是否严重暴力犯罪及其所处两种完成阶段(正在发生和拒捕逃跑)、有无不得使用武器的法定情形、是否紧急情形;最后,明确暴力犯罪、射击对象、紧急情形和不得使用武器情形的判明标准,不失为厘清问题的有益尝试。

关键词：使用武器条件判明情况警告无效紧急情形

美沙酮维持治疗对海洛因依赖者大脑度中心性影响的静息态fMRI研究

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磁共振成像 2024年第9期15卷 47-52页

作者：陈佳杰王志东金龙李玮李强王玮代晓峰空军军医大学第二附属医院放射诊断科西安710038 空军军医大学第二附属医院核医学科西安710038 中国人民解放军96604部队医院医学影像科兰州730030

目的探索美沙酮维持治疗(methadone maintenance treatment,MMT)对海洛因依赖(heroin dependence,HD)患者大脑拓扑特性度中心性(degree centrality,DC)的影响及其与心理行为学的相关性。材料与方法回顾性分析2016年1月至2017年12月于西安市灞桥区美沙酮门诊招募的41名正在接受MMT的HD患者,采集静息态功能磁共振成像(functional magnetic resonance imaging,fMRI)数据,评估稽延性戒断症状与渴求评分,纵向随访一年。对影像数据进行DC分析,并采用配对样本t检验进行纵向比较,差异脑区与心理学指标进行相关分析。结果HD患者入组时与MMT一年后稽延性戒断症状评分差异存在统计学意义(Z=3.004,P=0.003),渴求评分差异无统计学意义(Z=0.872,P=0.383)。与基线相比,HD患者经过MMT一年后,双侧丘脑、尾状核、壳核与左侧苍白球的DC降低;右侧舌回与距状回的DC值升高(Gaussian random field校正,单体素水平P95)。双侧尾状核及左侧苍白球DC值与戒断症状呈负相关性(r=-0.417,P=0.030;r=-0.392,P=0.043;r=-0.383,P=0.049),双侧壳核及左侧苍白球DC值的变化量与渴求的变化量呈正相关性(r=0.410,P=0.008;r=0.332,P=0.034;r=0.395,P=0.011)。结论美沙酮可能通过降低HD患者纹状体在成瘾奖赏脑网络中的中心性,从而调节HD患者戒毒后的稽延性戒断症状与心理渴求;同时可能抑制了冲动性,增强了视觉核心脑区的活动。该研究结果可以为美沙酮对HD患者治疗的神经机制提供影像学依据。

关键词：海洛因依赖美沙酮度中心性纹状体奖赏渴求磁共振成像

HPV疫苗接种对育龄期女性HPV感染的预防效果

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实用妇科内分泌电子杂志 2024年第12期11卷 12-15页

作者：王静向磊郝瑞峰陈强中国人民解放军63710部队医院检验病理科山西忻州036300

目的探讨人乳头瘤病毒(HPV)疫苗接种对育龄期女性HPV感染的预防效果。方法选取170例年龄24~50岁育龄期女性作为研究对象,根据是否接种过HPV疫苗分为试验组(接种过HPV疫苗,多为某部队现役人员及家属,生活习惯及受教育程度使得接种意识较... 详细信息

目的探讨人乳头瘤病毒(HPV)疫苗接种对育龄期女性HPV感染的预防效果。方法选取170例年龄24~50岁育龄期女性作为研究对象,根据是否接种过HPV疫苗分为试验组(接种过HPV疫苗,多为某部队现役人员及家属,生活习惯及受教育程度使得接种意识较高,感染率低)与对照组(未接种过HPV疫苗),各85例。采用实时荧光定量聚合酶链式反应(PCR)技术检测HPV高危型感染情况。比较两组疫苗预防效果、不良情绪及生活质量评分。结果试验组HPV持续感染、HPV高危型机会性感染、CINⅠ~Ⅱ级感染率(1.18%、2.35%、0)均低于对照组(9.41%、12.94%、7.06%),差异有统计学意义(P<0.05)。试验组焦虑自评量表(SAS)、抑郁自评量表(SDS)评分均低于对照组,差异有统计学意义(P<0.05)。试验组生活质量评分高于对照组,差异有统计学意义(P<0.05)。结论HPV疫苗接种对育龄期女性HPV感染具有明显预防效果,能显著降低HPV感染率,改善育龄期女性的情绪和生活质量,为育龄期女性群体预防HPV提供新的方案。

关键词： HPV疫苗接种育龄期女性预防效果

Ubiquitin at the crossroad of cell death and survival

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Chinese Journal of Cancer 2013年第12期32卷 640-647页

作者： Yu-Shan chen xiao-Bo Qiu Key Laboratory of Cell Proliferation and Regulation Biology Ministry of Education and College of Life Sciences Beijing Normal University

Ubiquitination is crucial for cellular processes,such as protein degradation,apoptosis,autophagy,and cell cycle *** of the ubiquitination network accounts for the development of numerous diseases,including ***,targeting ubiquitination is a promising strategy in cancer *** apoptosis and autophagy are involved in tumorigenesis and response to cancer *** both are categorized as types of cell death,autophagy is generally considered to have protective functions,including protecting cells from apoptosis under certain cellular stress *** review highlights recent advances in understanding the regulation of apoptosis and autophagy by ubiquitination.

关键词：细胞死亡泛素化十字路口细胞凋亡细胞周期进展癌症治疗自噬作用蛋白降解

The atom-bond connectivity index of chemical bicyclic graphs

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Applied Mathematics(A Journal of Chinese Universities) 2012年第2期27卷 243-252页

作者： chen Jin-song GUO xiao-feng College of Mathematics and Computer Science Hunan Normal University Changsha 410081 China. College of Mathematics and Computer Science Fuzhou University Fuzhou 350108 China. School of Mathematical Sciences Xiamen University Xiamen 361005 China.

The atom-bond connectivity（ABC） index provides a good model for the stability of linear and branched alkanes as well as the strain energy of cycloalkanes,which is defined as ABC（G） =∑ uv∈E（G） √d u＋dv-2 dudv,where du denotes the degree of a vertex u in G.A chemical graph is a graph in which no vertex has degree greater than *** this paper,we obtain the sharp upper and lower bounds on ABC index of chemical bicyclic graphs.

关键词： atom-bond connectivity index chemical bicyclic graph bound.

Expression and Purification of Recombinant MP-GFP Protein in Escherichia coli

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Agricultural Sciences in China 2011年第3期10卷 394-403页

作者： chen xiao-jun XU Han-hong Key Laboratory of Natural Pesticide and Chemical Biology Ministry of Education~South China Agricultural University Guangzhou510642 P.R.China School of Horticulture and Plant Protection Yangzhou University Yangzhou 225009 P..R. China

Guided pesticide is an unique compound resulted from the conjugation with carrier （amino acid, protein, sugars, etc） and the active pesticide ingredient. One of the attributes of the guided pesticide is its potential to accumulate at the site of the damaged points caused by pest or at the site of entry to the target pests, such as via inhalation, cuticular penetration, and oral digestion. Movement protein （MP） is a kind of protein coded by plant virus. A genetic fusion between green fluorescent protein （GFP） and movement protein resulted in the expression of a fluorescent fusion MP-GFP protein, which was fully biologically active in mediating the cell-to-cell spread of virus. In order to obtain a suitable carrier for a pesticide, fluorescent carrier MP-GFP was constructed. It was found that the recombinant MP-GFP protein was the inclusion body. The results indicated that optimized cultural condition for expression of recombinant MP-GFP protein was incubation at 37°C for 2 h and induction with 0.2 mmol L-1 IPTG （isopropyl-b-dthiogalactopyranoside） at 25°C for 4 h. MP-GFP protein was purified by using Ni-NTA resin. The expressed recombinant MP-GFP protein had both the fluorescence character of report GFP gene and moving character of movement protein. It could provide a guided carrier for studying the guided pesticide. It could also provide convenience for studying the delivery and distribution of the guided pesticide ingredients in the plant.

关键词： movement protein green fluorescent protein purification

Microstructure and properties of TiB_(2)-Ni coatings with different binder phase contents deposited by HVOF spray process

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Rare Metals 2022年第4期41卷 1385-1393页

作者： xiao chen Hong-Tao Wang Gang-Chang Ji xiao-Bo Bai Wei Fu School of Mechanical and Materials Engineering Jiujiang UniversityJiujiang 332005China

TiB_(2)–Ni coatings with different binder phase contents were sprayed on Q235 substrate by a high-velocity oxygen-fuel(HVOF)method using ball-milled *** microstructure,phase compositions,as well as thermal shock behavior,abrasive wear,and corrosion resistance to molten Al-12.07 wt%Si alloy performances of as-sprayed coatings were *** results show that the three TiB_(2)–Ni coatings structure is dense with low porosity,and the main phase compositions of the coatings are TiB_(2) and Ni similar to those of original *** coatings that have superior performance of thermal shock resistance have good bond to the substrate with no change in thick-ness and microstructure of ***,the coat-ings also have good durability in the molten Al-12.07 wt%Si after 60-h immersion *** the mass loss of Q235 steel is five times as much as that of TiB_(2)–50Ni coatings after abrasive wear test.

关键词： HVOF TiB_(2)-Ni Microstructure Abrasive wear Corrosion