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受限空间新型竖井提升机的布置

云南水力发电 2025年第1期41卷 104-106页

作者：贺斌王栋林薛小伟中国水利水电第十四工程局有限公司云南昆明650041

缙云抽蓄尾水调压井采用ME20+4.5T-12 m门式起重机作为提升系统,较传统使用矿用绞车作为提升系统来说,门式起重机具有安全可靠、施工效率高、操作简便、现场安全文明施工整体较好等优势,打开了竖井施工的局限性,文章重点介绍了新型门式... 详细信息

缙云抽蓄尾水调压井采用ME20+4.5T-12 m门式起重机作为提升系统,较传统使用矿用绞车作为提升系统来说,门式起重机具有安全可靠、施工效率高、操作简便、现场安全文明施工整体较好等优势,打开了竖井施工的局限性,文章重点介绍了新型门式竖井提升机在受限空间的布置方案,解决地下洞室门式起重机在空间上的制约。

关键词：门式起重机竖井施工抽水蓄能贝雷梁

Different structural origins for different sized surface pits observed on a-plane GaN film

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Science China(Technological Sciences) 2016年第1期59卷 156-161页

作者： GAO ZhiYuan LI JiangJiang xue xiaowei CUI BiFeng XING YanHui ZOU DeShu Microelectronic School Beijing University of Technology

A correlation study between the observed surface morphology using high-resolution scanning electron microscopy(HRSEM) and the observed structural imperfections using transmission electron microscopy(TEM) has been conducted for a-plane Ga N. There are three different sized asymmetric surface pits: large pit of 500 nm–2 ?m in side length, medium pit of 50 nm in side length, and small pit with side lengths of less than 5 nm, which originate from incomplete island coalescence, screw dislocation, and partial dislocation(PD), respectively. Both screw dislocation and PD can produce pits on the free surface because they have a perpendicular line tension to the surface, which must remain in balance with the surface tension. The two types of dislocation lead to distinctive pit sizes because the PD has a smaller Burgers vector component along the dislocation line than the pure screw dislocation. A pit that is produced in the island-coalescing process is much larger than those caused by dislocations because island coalescence is a kinetic process that involves large-scale mass transportation, whereas the dislocation mediates the surface in the local area. These three types of surface pits sometimes interact with one another in space. The coalescence of the island determines the surface morphology at large scales, whereas the defects affect the details.

关键词： surface pits nonpolar Ga N screw dislocations partial dislocations Island coalescence

Enhancing Mechanical Properties of Mg–6Zn Alloy by Deformation-Induced Nanoprecipitation

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Acta Metallurgica Sinica(English Letters) 2021年第2期34卷 217-226页

作者： Kai Yan Huan Liu xiaowei xue Jing Bai Honghui Chen Shuangquan Fang Jingjing Liu College of Mechanical Engineering Yangzhou UniversityYangzhou 225127China College of Mechanics and Materials Hohai UniversityNanjing 211100China Northern Jiangsu People’s Hospital Affiliated to Yangzhou University Yangzhou 225001China School of Materials Science and Engineering Southeast UniversityNanjing 211189China

We presented the solution of deformation-induced precipitation after homogenization to enhance the mechanical properties of Mg–6 Zn *** results show that the improved strategy exhibits more effective strengthening role than grain refinement methods based on low-temperature severe plastic deformation under the same *** low-temperature deformation with larger extrusion ratio results in massive nano-sized precipitates and excellent mechanical properties with the yield strength of 355 MPa and the ultimate tensile strength of 405 *** increased mechanical properties are strong and tough enough to resist the stress and not be worn away when the alloy nail penetrates through the pig thigh bone,potentially extending more orthopedic surgery applications for Mg–Zn alloys.

关键词： Mg–6Zn alloy Equal channel angular pressing Deformation-induced precipitation Severe plastic deformation Mechanical property

Prenatal ultrasonographic characteristics and prognosis of isolated redundant foramen ovale flap

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Gynecology and Obstetrics Clinical Medicine 2022年第3期2卷 141-146页

作者： Yuntao Li Qiuyan Pei Zhenjuan Yang Yani Yan xiaowei xue Department of Obstetrics&Gynecology Peking University People's HospitalNo 11 Xizhimen South StreetBeijing100044China

Objective:To analyze the prenatal ultrasonographic characteristics and prognosis of the isolated redundant foramen ovale flap(RFOF).Methods:From January 2014 to December 2021,we collected data on fetal echocardiography analyses and perinatal outcomes for fetuses with isolated RFOF in Peking University People's ***:We found that 0.31%(87/28308)of participants have *** four-chamber results of the foramen ovale flap(FOF)showed that it was stiff and extended>50%or reached the lateral wall of the left atrium(LA)in *** seen from the foramen ovale(FO)channel and four-chamber views,the hypermobile and redundant flap were observed shrinking and stretching with the fetal cardiac cycle,which is similar to *** lateral displacement of flow from LA to the left ventricle(LV)around the FOF on color doppler demonstrated thin linear blood flow from the right to left and a reversal of flow across FO.A uniphasic,but not biphasic,pattern of FOF displacement was observed on *** I(23/87)and II(51/87)had a higher ratio of ventricular disproportion than Stage 0(11/87)and III(2/87).We observed the RA/LA(right/left atrium)>1.2 in 53 cases(60.9%),RV/LV(right/left ventricle)>1.2 in 53 cases(60.9%),PA/AO(pulmonary/aortic artery)>1.2 in 53 cases(60.9%),and moderate or severe tricuspid regurgitation in 10 cases and moderate pericardial effusion in 2 cases(2.2%).Seventy-four RFOF cases had follow-up *** death occurred in 2 cases;72 fetuses survived with normal or minor heart ***:RFOF should be considered if the left side of the heart of a fetus is smaller and related to hypermobile *** isolated RFOF cases,a monthly follow-up is recommended to monitor arrhythmia or fetal hydrop *** treatment is recommended for those with adequate gestational age and lung maturity.

关键词： Isolated Redundant foramen ovale flap Fetal echocardiography Ultrasound Fetal outcome

Relationships between hemorrhage, angioarchitectural factors and collagen of arteriovenous malformations

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Neuroscience Bulletin 2012年第5期28卷 595-605页

作者： Hongchuan Niu Yong Cao xuejiang Wang xiaowei xue Lanbing Yu Ming Yang Rong Wang Department of Neurosurgery Beijing Tiantan Hospital affiliated to Capital Medical University Beijing 100050 China Department of Physiology and Pathophysiology School of Basic Medical Science Capital Medical University Beijing 100050 China

Objective While associations between the angioarchitecture of arteriovenous malformations （AVMs） in the brain and pathological features have been described, here we investigated the relationship between the angioarchitecture, the pathological features of the vessel wall, and hemorrhagic events. Methods The study was conducted on 43 patients： 16 with ruptured AVM （rAVM）, 15 with non-ruptured AVM （nrAVM）, 6 with craniocerebral trauma （control） and 6 with epilepsy （control）. The diagnosis of AVM was confirmed by preoperative digital subtraction angiography. Tissues were stained with hematoxylin and eosin and Masson＇s trichrome （for collagen fibers） to evaluate the vessel wall structure and endothelial integrity. The content and distribution of collagen types I and III in the vessel wall were assessed by immunohistochemical staining. Results In the nrAVM group, the nidus had more draining veins than the rAVM group （P 〈0.05）. Severely damaged endothelial cells, significantly fewer smooth muscle cells in the media, and hyperplasic type-I and -III collagen fibers were found in the rAVM group. The content of collagen types I and III in rAVMs was higher than that in the nrAVM （P 〈0.05） and control groups （P 〈0.01）. Conclusion There is an association between angioarchitectural features such as the number of draining veins and the pathological structure of the AVM wall. These abnormalities may contribute to AVM rupture.

关键词： arteriovenous malformations angioarchitecture pathology

Analysis of ultrasound clinical early warning system in hyper-coiling umbilical cord

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Chinese Medical Journal 2023年第20期136卷 2516-2517页

作者： Junshu Xie Yani Yan Zhenjuan Yang Yuntao Li xiaowei xue Xiaohong Zhang Qiuyan Pei Department of Obstetrics and Gynecology Peking University People’s HospitalBeijing 100044China

To the Editor:The umbilical cord is the vital link between the fetus and the *** proper spiral state of the umbilical cord plays a key role in maintaining its *** umbilical coiling index(UCI)is the number of spiral cycles per 1 cm of length and is normally 0.17,with UCI>0.30 considered hyper-coiling.^([1])Previous studies have identified hyper-coiling umbilical cord significantly associated with adverse pregnancy outcomes.^([2])However,many other studies have failed to find a strong correlation between abnormal coiling and adverse outcomes.^([3])Whether there are other abnormal ultrasound indicators in the hyper-coiling cord(HC)that can give early warning of adverse pregnancy still needs to be further explored.

关键词： fetus pregnancy umbilical

热层析成像在乳腺癌模型早期筛查中的应用价值

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中国医学科学院学报 2020年第2期42卷 236-241页

作者：薛小伟李俊来薛少伟张程中国人民解放军总医院第二医学中心超声科北京100853 中国人民解放军总医院第一医学中心超声科北京100853

目的拟获得肿瘤生长过程中热层析与超声图像,对比分析热层析检出乳腺癌的能力,探讨乳腺癌产热的血管病理基础。方法分别用NOD/SCID小鼠及SD大鼠乳腺癌模型动物进行热层析、超声、超声造影检查。随后对肿瘤组织进行CD34染色,研究肿瘤产... 详细信息

目的拟获得肿瘤生长过程中热层析与超声图像,对比分析热层析检出乳腺癌的能力,探讨乳腺癌产热的血管病理基础。方法分别用NOD/SCID小鼠及SD大鼠乳腺癌模型动物进行热层析、超声、超声造影检查。随后对肿瘤组织进行CD34染色,研究肿瘤产热与微观血管的关系。结果热层析成像可以早于超声检查2~4 d发现肿瘤,肿瘤组织内CD34表达增高且血管增粗、增多、不规则。结论热层析成像可以早期发现肿瘤组织,具有早期筛查乳腺癌的潜力。

关键词：热层析成像乳腺癌超声

磷酸肌酸钠联合果糖二磷酸钠治疗新生儿窒息后心肌损伤的疗效观察

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药物评价研究 2019年第12期42卷 2402-2405页

作者：齐荣薛小卫李园宝鸡市人民医院新生儿科

目的研究注射用磷酸肌酸钠联合果糖二磷酸钠注射液对新生儿窒息患儿心功能的影响。方法选择2015年1月-2018年6月宝鸡市人民医院收治的70例新生儿窒息后心肌损伤患儿作为研究对象,采用抽签法将患儿随机分为两组。对照组将果糖二磷酸钠注... 详细信息

目的研究注射用磷酸肌酸钠联合果糖二磷酸钠注射液对新生儿窒息患儿心功能的影响。方法选择2015年1月-2018年6月宝鸡市人民医院收治的70例新生儿窒息后心肌损伤患儿作为研究对象,采用抽签法将患儿随机分为两组。对照组将果糖二磷酸钠注射液250 mg/(kg·d)溶于30 mL的10%葡萄糖溶液中静脉滴注。观察组在对照组治疗的基础上,将注射用磷酸肌酸钠0.5 g溶于30 mL的10%葡萄糖溶液中静脉滴注。两组均治疗2周。观察两组患者的临床疗效,同时比较两组治疗前后的肌酸激酶同工酶(CK-MB)、肌钙蛋白T(CTnT)、肌酸激酶(CK)和乳酸脱氢酶(LDH)水平及左室射血分数(LVEF)。结果治疗后,观察组的总有效率为94.29%,明显高于对照组的71.43%(P<0.05)。治疗后,两组CKMB、CTnT、CK和LDH水平均明显降低(P<0.05);且观察组血清学指标显著低于对照组(P<0.05)。治疗后,两组LVEF均明显升高(P<0.05),且观察组显著高于对照组(P<0.05)。结论注射用磷酸肌酸钠联合果糖二磷酸钠注射液可以提高新生儿窒息后心肌损伤的疗效,有效改善心功能,具有临床推广应用价值。

关键词：注射用磷酸肌酸钠果糖二磷酸钠注射液新生儿窒息心肌损伤心功能

降雨环境中多输入多输出地-卫信道相关性研究

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电波科学学报 2013年第4期28卷 692-696页

作者：王燕薛小玮弓树宏吴振森江苏移动公司无锡分公司网络部江苏无锡214074 西安电子科技大学理学院陕西西安710071

利用随机介质中波传播理论研究了随机雨介质中信号的起伏特性,研究了降雨散射环境中,卫星通信多输入多输出(Multi-Input Multi-Output,MIMO)信道相关性对多径信道的影响,导出了降雨环境下接收端天线相关系数和发射端天线相关系数的计算... 详细信息

利用随机介质中波传播理论研究了随机雨介质中信号的起伏特性,研究了降雨散射环境中,卫星通信多输入多输出(Multi-Input Multi-Output,MIMO)信道相关性对多径信道的影响,导出了降雨环境下接收端天线相关系数和发射端天线相关系数的计算公式,并对发射端相关系数和接收端相关系数作了进一步讨论.结果表明:降雨环境下,天线间距、发射频率、降雨率等因素对卫星通信MIMO系统相关系数有着重要影响.

关键词： MIMO 降雨环境相关系数发射端接收端