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Shape Memory Effect Induced by Stress-induced α' Martensite in a Metastable Fe–Cr–Ni Austenitic Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2017年第6期30卷 513-520页

作者： Yong-Ning Wang Jie Chen hua-bei Peng Yu-hua Wen School of Manufacturing Science and Engineering Sichuan UniversityChengdu 610065China School of Aeronautics and Astronautics Sichuan UniversityChengdu 610065China

It is not clear whether a shape memory effect （SME） can be realized by stress-induced α＇ martensite in metastable austenitic stainless steels although the stress-induced ε martensite in these materials can result in the SME. To clarify this problem, the relationship between the shape recovery and the reverse transformation of the stress-induced ε and α＇ martensite in a 304 stainless steel was investigated. The results show that the stress-induced α＇ martensite can result in the SME when heating above 773 K. After deformation at 77 K and step heating or directly holding at 1073 K, two-stage shape recoveries below 440 K and above 773 K can be obtained due to the reverse transformation of the stress-induced ε martensite and α＇ martensite, respectively. After deformation at room temperature, the α＇ martensite produced can result in the SME only when directly holding at 1073 K. The intrusion of more dislocations before the formation of the α＇ martensite at room temperature than at 77 K is the reason that the α＇ martensite induced at room temperature cannot result in the SME in the case of slow heating. The recovered strains resulting from the stress-induced ε and α＇ martensite are proportional to the amounts of their reverse transformation, respectively.

关键词： Austenitic stainless steel Shape memory effect Alpha prime martensite Epsilon martensite Two-stage recoveries

门诊患者膝关节腔注射治疗中应用专科护理小组多学科合作模式的效果分析

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中国社区医师 2024年第15期40卷 134-136页

作者：林永霞孔旭陆贝江苏省苏北人民医院输液室江苏扬州225001

目的:分析在门诊患者膝关节腔注射治疗中应用专科护理小组多学科合作模式的效果。方法:选取2020年6月—2021年3月于苏北人民医院门诊注射室行膝关节腔注射治疗的260例患者作为研究对象,将2020年6—10月的130例患者设为对照组,2020年11月... 详细信息

目的:分析在门诊患者膝关节腔注射治疗中应用专科护理小组多学科合作模式的效果。方法:选取2020年6月—2021年3月于苏北人民医院门诊注射室行膝关节腔注射治疗的260例患者作为研究对象,将2020年6—10月的130例患者设为对照组,2020年11月—2021年3月的130例患者设为观察组。对照组实施常规护理,观察组建立专科护理小组并实施多学科合作模式。比较两组护理效果。结果:观察组穿刺失败、穿刺部位感染、疼痛加剧、残肢血运障碍及并发症总发生率高于对照组,差异有统计学意义(P<0.05)。观察组满意率高于对照组,差异有统计学意义(P=0.043)。结论:门诊患者膝关节腔注射治疗中建立专科护理小组的效果显著,能够降低并发症发生率,提高患者满意度,值得临床应用并予以推广。

关键词：专科护理小组门诊关节腔注射并发症护理质量

烧结温度对SiC-Al_(2)O_(3)-Y_(2)O_(3)-MgO陶瓷性能影响的研究

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中国陶瓷 2024年第8期60卷 24-29页

作者：孔维静鹿桂花周恒为喀什大学物理与电气工程学院喀什844000 伊犁师范大学物理科学与技术学院新疆凝聚态相变与微结构实验室伊宁835000

采用X射线衍射仪、扫描电子显微镜和硬度计研究了烧结助剂在最佳烧结温度下对SiC陶瓷的结构、形貌和性能的影响。结果表明:采用无压液相烧结合成SiC复合陶瓷,样品颗粒较为均匀,随着烧结温度的升高,样品的质量损失,气孔率和线收缩率均增... 详细信息

采用X射线衍射仪、扫描电子显微镜和硬度计研究了烧结助剂在最佳烧结温度下对SiC陶瓷的结构、形貌和性能的影响。结果表明:采用无压液相烧结合成SiC复合陶瓷,样品颗粒较为均匀,随着烧结温度的升高,样品的质量损失,气孔率和线收缩率均增加,而硬度先增加后减小。当烧结温度为1850℃时,陶瓷的硬度最高为30.4 GPa,热膨胀系数为3.68×10^(-6)/℃(室温至500℃温区范围内),最接近单晶硅的热膨胀系数(3.5×10^(-6)/℃),介电常数约为24.63,介电损耗最低,tanδ约为0.006,是一种致密性好,硬度高的碳化硅复合陶瓷材料。

关键词：碳化硅复合陶瓷烧结温度热膨胀

Current Phthalate Exposure Risks of Rural Population in the Northwest China: Evidence from an Internal Exposure Study

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Environment & Health 2024年第8期2卷 586-595页

作者： Yawen Zheng Liting hua Zining Zhang Lin Zhu Hongkai Zhu Hongwen Sun Hongzhi Zhao Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria College of Environmental Science and EngineeringNankai UniversityTianjin 300350China School of Urban and Environmental Sciences Key Laboratory of the Ministry of Education for Earth Surface ProcessesPeking UniversityBeijing 100871China State Key Laboratory of Environmental and Biological Analysis Department of ChemistryHong Kong Baptist UniversityHong KongChina

Phthalates(PAEs)are synthetic chemicals widely used in industrial and personal consumer products as adhesives or *** have been demonstrated to have toxic effects on the human ***,biological monitoring data for the internal PAE exposure levels of Chinese rural residents are still *** present study investigated the exposure levels of ten phthalate metabolites(mPAEs)of rural residents in Northwest *** results showed that mPAEs were wildly prevalent in urine and the geometric mean concentration ofΣ10mPAEs was 957.02 ng mL^(–1)(adjusted by specific gravity).Mono-n-butyl phthalate(MBP)and metabolites of di(2-ethylhexyl)-phthalate(DEHP)were the most dominant mPAEs in urine,with specific gravity adjusted median concentrations of 174.67 and 156.30 ng mL^(–1),*** concentrations of mPAEs were significantly associated with age,body mass index and economic level(p<0.05).By calculating the percentage and relative conversion rate of DEHP metabolites,it was found that the degree of oxidative metabolism of DEHP in children was significantly higher than that in adults(p<0.05),indicating that the pathway and degree of DEHP oxidation were *** risk assessment showed that 59.12%of rural residents may have a noncancer risk from PAE *** study provides important basis for assessing the occurrence and exposure of urinary phthalate metabolites among rural residents in China.

关键词： Phthalate Metabolites Human Biomonitoring Health Risk Assessment Rural Residents

SARS-CoV-2 ORF10 hijacking ubiquitination machinery reveals potential unique drug targeting sites

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Acta Pharmaceutica Sinica B 2024年第9期14卷 4164-4173页

作者： Kaixiang Zhu Lili Song Linyue Wang Lei hua Ziyu Luo Tongyun Wang Bo Qin Shuofeng Yuan Xiaopan Gao Wenyi Mi Sheng Cui NHC Key Laboratory of Systems Biology of Pathogens National Institute of Pathogen BiologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Key Laboratory of Pathogen Infection Prevention and Control(Peking Union Medical College) Ministry of EducationBeijing 100730China The Province and Ministry Co-Sponsored Collaborative Innovation Center for Medical Epigenetics Key Laboratory of Immune Microenvironment and Disease(Ministry of Education)Tianjin Medical University General HospitalDepartment of ImmunologyTianjin Medical UniversityTianjin 300070China Medical School Yan’an UniversityShaanxi ProvinceYan’an 716000China State Key Laboratory of Emerging Infectious Diseases Li Ka Shing Faculty of Medicinethe University of Hong KongPokfulamHong Kong SARChina Department of Microbiology Li Ka ShingFaculty of Medicinethe University of Hong KongPokfulamHong Kong SARChina

Viruses often manipulate ubiquitination pathways to facilitate their replication and ***2ZYG11B known as the substrate receptor of cullin-2 RING E3 ligase,is bound by SARS-CoV-2 ORF10 to increase its E3 ligase activity,leading to degradation of IFT46,a protein component of the intraflagellar transport(IFT)complex *** results in dysfunctional cilia,which explains certain symptoms that are specific to ***,the precise molecular mechanism of how ORF10 recognizes CUL2ZYG11B remains ***,we determined the crystal structure of CUL2ZYG11B complexed with the N-terminal extension(NTE)of SARS-CoV-2 ORF10(2.9 A°).The structure reveals that the ORF10 N-terminal heptapeptide(NTH)mimics the Gly/N-degron to bind *** studies identified key residues within ORF10 that are key players in its interaction with CUL2ZYG11B both in ITC assay and in vivo *** addition,we prove that enhancement of CUL2ZYG11B activity for IFT46 degradation by which ORF10-mediated correlates with the binding affinity between ORF10 and ***,we used a Global Protein Stability system to show that the NTH of ORF10 mimics the Gly/N-degron motif,thereby binding competitively to CUL2ZYG11B and inhibiting the degradation of target substrates bearing the Gly/N-degron ***,this study sheds light on how SARS-CoV-2 ORF10 exploits the ubiquitination machinery for proteasomal degradation,and offers valuable insights for optimizing PROTAC-based drug design based on NTH CUL2ZYG11B interaction,while pinpointing a promising target for the development of treatments for COVID-19.

关键词： SARS-CoV-2 ORF10 Crystal structure cullin-2 RING E3 ligase Drug design

体素内不相干运动扩散加权磁共振在食管癌术前分期及分化程度中的应用价值分析

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世界复合医学 2024年第4期10卷 171-174页

作者：孔琳朱华宫悦东台市人民医院影像科江苏东台224200

目的探究体素内不相干运动扩散加权磁共振(incoherent motion diffusion-weighted MRI,IVIM-DWI)在食管癌术前分期及分化程度中的应用价值。方法选择2020年10月—2023年8月东台市人民医院收治的87例疑似食管癌患者作为研究对象,所有... 详细信息

目的探究体素内不相干运动扩散加权磁共振(incoherent motion diffusion-weighted MRI,IVIM-DWI)在食管癌术前分期及分化程度中的应用价值。方法选择2020年10月—2023年8月东台市人民医院收治的87例疑似食管癌患者作为研究对象,所有患者术前均接受IVIM-DWI扫描,以病理学检查为金标准,分析IVIM-DWI扫描对食管癌术前分期及分化程度的诊断效能及符合率。结果病理学检查结果显示,81例确诊为食管癌,IVIM-DWI扫描确诊80例,IVIM-DWI的准确度、灵敏度、特异度分别为97.70%、98.77%、83.33%,kappa值为0.821。经病理学检查检查,81例食管癌患者中,恶性肿瘤分期系统(tumor node metastasis classification,TNM)Ⅰ期39例,TNMⅡ期30例,TNMⅢ期12例;高分化15例,中分化26例,低分化40例。IVIM-DWI扫描TNMⅠ期40例(97.50%),TNMⅡ期30例(100.00%),TNMⅢ期10例(91.67%);IVIM-DWI扫描高分化13例(86.67%),中分化27例(96.30%),低分化40例(100.00%)。结论 IVIM-DWI在食管癌术前分期及分化程度中具有较高的诊断效能,可作为食管癌术前分期、分化程度的优选诊疗方案。

关键词：体素内不相干运动扩散加权磁共振食管癌分期及分化程度诊断效能

Effectiveness of Surface Coatings Against Intensified Sewage Corrosion of Concrete

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Journal of Wuhan University of Technology(Materials Science) 2019年第5期34卷 1177-1186页

作者： kong Lijuan FANG Jun ZHANG bei School of Materials Science and Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050043China Hebei Provincial Key Laboratory of Traffic Engineering Materials Shijiazhuang Tiedao UniversityShijiazhuang 050043China

Three different kinds of coatings were coated on the concrete surface, and the changes in appearance, surface roughness, microstructure and components of coatings in artificial sewage were investigated. In addition, the strength, micrograph, mineral compositions and pore structure of concrete specimens after removing coatings were also studied. The results show that epoxy coal tar pitch coating(ECTPC) has the best effect of protecting concrete from the sewage corrosion. After being immersed in sewage for 90 days, the compressive strength of concrete coated with ECTPC is still as high as that of specimen immersed in water, and the cement paste has a high CH content and dense structure with low porosity, which mainly accounts for its excellent barrier property and certain antibacterial function. Cement-based bactericidal coating(CBC) also has good effectiveness to sewage corrosion of concrete. The strength and microstructure of concrete coated with CBC in sewage are still significantly superior to those of uncoated concrete. Although cement-based capillary crystalline waterproofing coating(CCCWC) is a good waterproof material, it is not suitable for the corrosion resistance of concrete in sewage. After 2 months corrosion, almost all of the CH crystals in coating reacted with the metabolic acid substance by microbes. Therefore, the strength and pore structure of concrete coated with CCCWC are only slightly superior to those of uncoated concrete. Overall, the protective effect of cement-based inorganic coatings is relatively poor.

关键词： surface coating concrete sewage corrosion biological adaptability protection

Hamiltonian analysis of 4-dimensional spacetime in Bondi-like coordinates

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Chinese Physics C 2018年第10期42卷 142-159页

作者： Chao-Guang huang Shi-bei kong Theoretical Physics Division Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

We discuss tile Hamiltonian formulation of gravity in four-dimensional spacetime under Bondi-like coordinates {v,r,xa,a=2,3}. In Bondi-like coordinates, the three-dimensional hypersurface is a null hypersurface, and the evolution direction is the advanced time v. The internal symmetry group SO（1,3） of the four-dimensional spacetime is decomposed into SO（1,1）, SO（2）, and T^±（2）, whose Lie algebra s0（1,3） is decomposed into s0（1,1）, s0（2）, and t^± （2） correspondingly. The SO（1,1） symmetry is very obvious in this type of decomposition, which is very useful in s0（1,1） BF theory. General relativity can be reformulated as the four-dimensional coframe （eμ^I） and connection （ωμ^IJ） dynamics of gravity based on this type of decomposition in the Bondi-like coordinate system. The coframe consists of two null 1-forms e-, e＋ and two spacelike 1-forms e2, e3. The Palatial action is used. The Hamiltonian analysis is conducted by Dirac＇s methods. The consistency analysis of constraints has been done completely. Among the constraints, there are two scalar constraints and one two-dimensional vector constraint. The torsion-free conditions are acquired from the consistency conditions of the primary constraints about πIJ^μg. The consistency conditions of the primary constraints πIJ^0= 0 can be reformulated as Gauss constraints. The conditions of the Lagrange multipliers have been acquired. The Poisson brackets among the constraints have been calculated. There are 46 constraints including 6 first-class constraints πIJ^0= 0 and 40 second-class constraints. The local physical degrees of freedom is 2. The integrability conditions of Lagrange multipliers no, 10, and eA are Ricci identities. The equations of motion of the canonical variables have also been shown.

关键词： Hamiltonian analysis 4d gravity Bondi-like coordinates

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私有信息、个人投资者行为与股价异常波动

管理科学学报 2024年第2期27卷 120-135页

作者：孔傲李昊骅李心丹朱洪亮南京财经大学金融学院南京210023 南京大学工程管理学院南京210093

股价异常波动危害投资者权益和股市安全,厘清股价异常波动的原因对于股市监管具有重要意义.本文从个股高频数据中提取股价中的私有信息含量,检验私有信息与中国A股市场个股异常波动的关系,并基于独特的账户数据分析个人投资者行为在这... 详细信息

股价异常波动危害投资者权益和股市安全,厘清股价异常波动的原因对于股市监管具有重要意义.本文从个股高频数据中提取股价中的私有信息含量,检验私有信息与中国A股市场个股异常波动的关系,并基于独特的账户数据分析个人投资者行为在这一关系中的作用.结果表明,排除市场因素的影响后,无论是否有公司层面的消息发布,私有信息都与股价异常波动的发生概率显著正相关,而个人投资者在这一关系中发挥了中介作用.进一步的研究发现,个人投资者的中介作用在股价暴涨和暴跌时有显著的非对称性:在股价上涨过程中,私有信息促进了个人投资者跟风买入的助涨行为,增大了股价暴涨的概率,而在股价下跌过程中,私有信息抑制了其抄底买入的止跌行为,也增大了股价暴跌的概率.本文的启示是,中国股市个股暴涨常常受到机构投资者和个人投资者的共同推动,而个股暴跌则是伴随机构投资者推跌和个人投资者提供流动性稳定股市的过程.

关键词：股价异常波动私有信息个人投资者行为反馈交易