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A Positron Study of Hysteresis Temperature in Ti-Ni Alloy

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Journal of Materials Science & Technology 1996年第6期12卷 470-472页

作者： wang, jc Qin, GY Zhang, GL Zheng, WH Chen, LY Gu, M ACAD SINICA SHANGHAI INST NUCL RESSHANGHAI 201800PEOPLES R CHINA TONGJI UNIV DEPT PHYSSHANGHAI 200092PEOPLES R CHINA

For Ti-Ni alloy, it is exceedingly difficult; to prepare an element that has a desired and defined hysteresis temperature for its preparing process is not perfect at present. Because the mechanism of transformation in Ti-Ni has not been fully clarified, it is far more exceedingly difficult to explain the hysteresis temperature only by using the traditional metal physics techniques. But position annihilation seems to be a suitable method for it. The positron annihilation measurements show that the hysteresis temperature may be controlled mainly by the relative fraction of the defects contained in a two-way shape memory element.

关键词： Titanium alloys

Positron Study of Origin of Thermoelastic MartensiteStabilization for a Cu-Zn-Al Alloy

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Journal of Materials Science & Technology 1996年第5期12卷 377-380页

作者： wang, jc Shao, ZC Zhang, GL Zheng, WH Yu, FH Chen, LY Gu, M ACAD SINICA SHANGHAI INST NUCL RESSHANGHAI 201800PEOPLES R CHINA TONGJI UNIV DEPT PHYSSHANGHAI 200092PEOPLES R CHINA

A series of Cu-23Zn-10Al (at pet) alloy specimens subjected to different heat-treatment processes have been studied by means of Doppler broadening technique of positron annihilation combined with mechanical test. Results show that the mechanism of quenched-in vacancies, instead of the other suggested ones, plays a dominant role in thermoelastic martensite stabilization of Cu-based shape memory alloy. Knowing the character of the movement of quenched-in vacancies and eliminating them as rapidly as possible are the basis for further optimizing heat-treatment process to obtain desired shape memory performance.

关键词： Shape memory effect

Mechanism of frost heave by film water migration under temperature gradient

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Chinese Science Bulletin 1997年第15期42卷 1290-1294页

作者： Xu, XZ wang, jc Zhang, LX Deng, YS Chuvilin, EM Yershov, ED Ishizaki, T Fukuda, M State Key Laboratory of Frozen Soil Engineering Lanzhou Institute of Glaciology and Geocryology Chinese Academy of Sciences Lanzhou China Geological Faculty of Moscow University Russia Institute of Low Temperature Science Hokkaido University Japan

IT is well known that there exists unfrozen film water in frozen soils due to the action of sur-face energy among soil particles and frost heave occurs by water migration under the tempera-ture gradient. The problem is how to determine the amount of frost heave quantitatively. The amount of frost heave induced by ice segregation can be calculated by the following e-quations:

关键词： temperature gradient film water frost heave.

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水乡古镇─—周庄

华中建筑 1995年第2期13卷 51-56页

作者： wang,jc 王绰美国弗吉尼亚理工大学建筑城市学院建筑系

文章介绍了江南水乡方镇─—周庄。从地理位置、自然环境、历史沿革、人文景观等方面勾勒出古镇的风貌及其人文、经济、地理特征。通过与名城苏州的比较，指出在经济大潮中，保护与开发利用古镇人文地理资源的途径。

关键词：水乡古镇环境景观拱桥水道城乡规划

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骨髓间充质干细胞移植治疗脑梗死的相关研究

中国组织工程研究与临床康复 2007年第33期11卷 6657-6660页

作者：闻霞孙锋王金春沈阳市第五人民医院神经内科辽宁省沈阳市110023

学术背景:目前已有将骨髓间质干细胞用于脑梗死动物模型治疗的报道,国内外有关骨髓间质干细胞用于治疗脑梗死的研究也取得了一些进展,但是对于其作用机制还不清楚,国内外有关这方面的争论比较多。目的:就骨髓间质干细胞治疗脑梗死的研... 详细信息

学术背景:目前已有将骨髓间质干细胞用于脑梗死动物模型治疗的报道,国内外有关骨髓间质干细胞用于治疗脑梗死的研究也取得了一些进展,但是对于其作用机制还不清楚,国内外有关这方面的争论比较多。目的:就骨髓间质干细胞治疗脑梗死的研究进展及其治疗作用机制进行综述。检索策略:由第一、三作者应用计算机检索PUBMED 2000-07/2007-03期间与骨髓间充质干细胞和脑梗死有关的文章,检索词为"mesenchymal stem cells,cerebral ischemia,stroke"并限定文章语言种类为"English"。同时计算机检索中国期刊全文数据库2002-01/2007-03相关的文章,检索词为"骨髓间质干细胞,移植,脑梗死",并限定文章语言种类为中文。纳入标准:文章所述内容应与骨髓间质干细胞治疗脑梗死的应用研究及其治疗作用机制研究相关。排除标准:重复研究。文献评价:共收集到300篇相关文献,排除248篇内容陈旧或重复的文献,52篇符合纳入标准,有51篇检索到全文,选用其中的33篇作为本文参考文献:16篇涉及骨髓间质干细胞移植治疗脑梗死的相关研究;8篇神经干细胞移植后的示踪标记相关研究文章;5篇脑血管疾病干细胞移植治疗现状相关文章。资料综合:骨髓间质干细胞具有多向分化潜能,在特定条件下可分化为具有神经元形态并表达神经元标记物的细胞,在脑内可与损伤的细胞融合,能分泌营养因子或者刺激损伤部位产生内源性因子,促进损伤组织的修复并减少细胞凋亡,已成为细胞移植治疗各种疾病的理想种子细胞。结论:骨髓间质干细胞对脑梗死具有较好的治疗作用,主要通过其移植后能够分泌大量营养因子从而发挥其神经保护作用和营养支持作用。

关键词：骨髓间质干细胞移植脑梗死综述文献

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对一种口腔锥形束CT的有效剂量的估算

中华放射医学与防护杂志 2017年第3期37卷 222-225页

作者：罗葳赵越王建超北京大学人民医院口腔科 100044 中国疾病预防控制中心辐射防护与核安全医学所核应急中国预防控制中心重点实验室北京100008

目的从测量一种口腔锥形束CT（CBCT）扫描机的剂量面积乘积（DAP），使用一个转换系数估算有效剂量。方法使用DAP测量方法对一台柯达（KODAK）9500扫描机使用2个视野：16cm×15cm和12cm×8cm。将一台瑞典RTI产DAP（Doseguard 100）仪器... 详细信息

目的从测量一种口腔锥形束CT（CBCT）扫描机的剂量面积乘积（DAP），使用一个转换系数估算有效剂量。方法使用DAP测量方法对一台柯达（KODAK）9500扫描机使用2个视野：16cm×15cm和12cm×8cm。将一台瑞典RTI产DAP（Doseguard 100）仪器配套透射电离室贴在机器X射线管出线口处测量每种曝光方案的DAP值（mGy·am2），所有测量重复3次取平均。引用文献中一个转换系数为0．080μSv／mGy·cm2对柯达扫描机，每一个平均DAP值估算有效剂量。结果对于KODAK9500机器在2个视野的DAP值变化范围从512到1083mGy·cm2和用0．080μSv／mGy·cm2估算有效剂量从41到87μSv。发现与文献中3台KODAK9500机器有效剂量相比，本研究得到的有效剂量明显偏低。结论发现对口腔CBCT扫描机进行DAP测量是一种很好定义和快捷测量的方法，通过选择一个适当转换系数可以估算有效剂量。然而，对不同类型口腔CBCT机器如何适当地选用转换系数，需要进一步加以细致地研究。

关键词：锥形束计算机体层摄影剂量面积乘积有效剂量转换系数

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He Li Li Sai wang Shao-Jiang wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 509-521页

作者： Xinyuan wang Fan Zhang Xingyu Zhou Qian wang Changyu Liu Yangyang Liu Hui wang Xiaojie Liu Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry & Materials Science Northwest University

Na3V2（PO4）2O2F （VP） is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory （DFT） and finite element simulations show that incorporating SO42-into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge ***,the average Na+diffusion coefficient of Na3V2（PO4）1.95（SO4）0.05O2F（VPS-1） is roughly double that of VP,leading to enhanced rate capability (80 C,75.5 mAh g-1) and cycling stability (111.0 mAh g-1capacity after 1000 cycles at 10 C current density) for ***-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 *** assembled VPS-1//SbSn/NPC full cell demonstrated stable cycling over 200 cycles at a high 5 C current,maintaining an average coulombic efficiency of 95.35%.

关键词： Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate Cathode

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难治性慢性骨髓炎35例临床分析

新乡医学院学报 2003年第1期20卷 32-33页

作者：王琪杨继辰新乡市第二人民医院骨科河南新乡453002

目的　探讨难治性慢性骨髓炎的治疗原则和方法。方法　对 3 5例难治性慢性骨髓炎患者在彻底清除病灶的基础上 ,动态观察局部细菌变化 ,依骨缺损的长度一期支撑植骨 ,采用转移皮瓣、肌瓣或肌皮瓣修复软组织缺损 ,局部置管滴注引流抗生素... 详细信息

目的　探讨难治性慢性骨髓炎的治疗原则和方法。方法　对 3 5例难治性慢性骨髓炎患者在彻底清除病灶的基础上 ,动态观察局部细菌变化 ,依骨缺损的长度一期支撑植骨 ,采用转移皮瓣、肌瓣或肌皮瓣修复软组织缺损 ,局部置管滴注引流抗生素溶液 ,选择应用合适的内、外固定器固定。结果　经综合治疗 ,全部病例感染得以彻底控制 ,平均治愈时间为 13个月 ,保证了肢体长度的均衡。结论　治性慢性骨髓炎 ,应动态观察细菌变化 ,针对性应用抗生素 ,一期支撑植骨可恢复肢体长度。

关键词：慢性骨髓炎旋转皮瓣植骨综合治疗