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Origin of the anomalous trends in band alignment of GaX/ZnGeX_2(X = N, P, As, Sb) heterojunctions

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Journal of Semiconductors 2019年第4期40卷 17-21页

作者： Ruyue Cao Hui-Xiong Deng Jun-wei Luo Su-huai wei State Key Laboratory of Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences University of Chinese Academy of Sciences Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Beijing Computational Science Research Center

Utilizing first-principles band structure method, we studied the trends of electronic structures and band offsets of the common-anion heterojunctions GaX/ZnGeX_2(X = N, P, As, Sb). Here, ZnGeX_2 can be derived by atomic transmutation of two Ga atoms in GaX into one Zn atom and one Ge atom. The calculated results show that the valence band maximums(VBMs) of GaX are always lower in energy than that of ZnGeX_2, and the band offset decreases when the anion atomic number increases. The conduction band minimums(CBMs) of ZnGeX_2 are lower than that of GaX for X = P, As, and Sb, as expected. However, surprisingly, for ZnGeN2, its CBM is higher than GaN. We found that the coupling between anion p and cation d states plays a decisive role in determining the position of the valence band maximum, and the increased electronegativity of Ge relative to Ga explains the lower CBMs of ZnGeX_2 for X = P, As, and Sb. Meanwhile, due to the high ionicity, the strong coulomb interaction is the origin of the anomalous behavior for nitrides.

关键词： GaX/ZnGeX2 heterojunctions band offsets atomic orbital coupling

Pain perception enhancement in consecutive secondeye phacoemulsification cataract surgeries under topical anesthesia

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1510-1518页

作者： Jia-wei Luo Yan-Hua Chen Jian-Feng Yu Yi-Xun Chen Min Ji huai-Jin Guan Eye Institute Affiliated Hospital of Nantong UniversityMedical School of Nantong UniversityNantong 226001Jiangsu ProvinceChina Nantong Center for Disease Control and Prevention Nantong 226001Jiangsu ProvinceChina

Cataract is the main cause of visual impairment and blindness worldwide while the only effective cure for cataract is still *** phacoemulsification under topical anesthesia has been the routine procedure for cataract ***,patients often grumbled that they felt more painful during the second-eye surgery compared to the first-eye *** intraoperative pain experience has negative influence on satisfaction and willingness for second-eye cataract surgery of patients with bilateral *** ocular pain is a complicated process induced by the nociceptors activation in the peripheral nervous ***,neuropsychological,and pharmacological factors work together in the enhancement of intraoperative *** published literatures have focused on the pain enhancement during the secondeye phacoemulsification *** this review,we searched PubMed database for articles associated with pain perception differences between consecutive cataract surgeries published up to Feb.1,*** summarized the recent research progress in mechanisms and interventions for pain perception enhancement in consecutive secondeye phacoemulsification cataract *** review aimed to provide novel insights into strategies for improving patients’intraoperative experience in second-eye cataract surgeries.

关键词： ocular pain cataract surgery topical anesthesia intraoperative experience second-eye phacoemulsification

Mechanical and damping performances of TPMS lattice metamaterials fabricated by laser powder bed fusion

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China Foundry 2024年第4期21卷 327-333页

作者： Yan-peng wei huai-qian Li Jing-jing Han Ying-chun Ma Hao-ran Zhou Jing-chang Cheng Jian Shi Zhi-quan Miao Bo Yu Feng Lin National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China

Lattice metamaterials based on three-period minimum surface(TPMS)are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ***,its vibration and noise reduction,and damping properties have not been fully ***,in this study,the TPMS structures with parameterization were designed by the method of surface migration,and the TPMS structures with high forming quality was manufactured by laser powder bed fusion(LPBF).The mechanical properties and energy absorption characteristics of the beam and TPMS structures were studied and compared by quasi-static *** modal shapes of the beam lattice structures and TPMS structures were obtained by the free modal analysis,and the damping properties of two structures were obtained by modal *** the two structures after heat treatment with the same porosity of 70%,the yield strength of the beam lattice structure reaches 40.76 MPa,elastic modulus is 20.38 GPa,the energy absorption value is 32.23 MJ·m^(-3),the damping ratio is 0.52%.The yield strength,elastic modulus,energy absorption value,and damping ratio of the TPMS structure are 50.74 MPa,25.37 GPa,47.34 MJ·m^(-3),and 0.99%,*** results show that TPMS structures exhibit more excellent mechanical properties and energy absorption,better damping performance,and obvious advantages in structural load and vibration and noise reduction compared with the beam lattice structures under the same porosity.

关键词： lattice metamaterials TPMS energy absorption damping laser powder bed fusion

Link between mutations in ACVRL1 and PLA2G4A genes and chronic intestinal ulcers:A case report and review of literature

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 932-943页

作者： Yong-Jing Tang Jian Zhang Jie Wang Ren-Dong Tian wei-wei Zhong Ben-Sheng Yao Bing-Yu Hou Ying-Hua Chen wei He Yi-huai He Department of Infectious Diseases The Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina Department of Gastroenterology Dafang County People's HospitalBijie 551600Guizhou ProvinceChina Department of Internal Medicine Puchang BranchMedical CommunitySuiyang County People's HospitalZunyi 563300Guizhou ProvinceChina Department of Infectious Diseases Jingmen Central HospitalJingmen 448000Hubei ProvinceChina Department of Infectious Diseases Dafang County People's HospitalBijie 551600Guizhou ProvinceChina

BACKGROUND Genetic factors of chronic intestinal ulcers are increasingly garnering *** present a case of chronic intestinal ulcers and bleeding associated with mu-tations of the activin A receptor type II-like 1(ACVRL1)and phospholipase A2 group IVA(PLA2G4A)genes and review the available relevant *** SUMMARY A 20-year-old man was admitted to our center with a 6-year history of recurrent abdominal pain,diarrhea,and dark *** the onset 6 years ago,the patient had received treatment at a local hospital for abdominal pain persisting for 7 d,under the diagnosis of diffuse peritonitis,acute gangrenous appendicitis with perforation,adhesive intestinal obstruction,and pelvic *** surgical treat-ment included exploratory laparotomy,appendectomy,intestinal adhesiolysis,and pelvic abscess *** patient’s condition improved and he was ***,the recurrent episodes of abdominal pain and passage of black stools started again one year after *** the basis of these features and results of subsequent colonoscopy,the clinical diagnosis was established as in-flammatory bowel disease(IBD).Accordingly,aminosalicylic acid,immunotherapy,and related symptomatic treatment were administered,but the symptoms of the patient did not improve *** investigations revealed mutations in the ACVRL1 and PLA2G4A ***1 and PLA2G4A are involved in angiogenesis and coagulation,*** suggests that the chronic intestinal ulcers and bleeding in this case may be linked to mutations in the ACVRL1 and PLA2G4A *** Kangfuxin liquid was administered to promote healing of the intestinal mucosa and effectively manage clinical *** Mutations in the ACVRL1 and PLA2G4A genes may be one of the causes of chronic intestinal ulcers and bleeding in *** administered Kangfuxin liquid may have therapeutic potential.

关键词： Intestinal ulcers Crohn’s disease Ulcerative colitis Activin A receptor type II-like 1 Phospholipase A2 group 4A Case report

反常色散增益光纤构建无源自相似脉冲光纤激光器

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光子学报 2023年第8期52卷 72-84页

作者：龚睿耿亚林裴丽魏淮北京交通大学电子信息工程学院光波技术研究所全光网络与现代通信网教育部重点实验室北京100044

通常自相似脉冲光纤激光器的增益光纤都为正常色散,而利用色散补偿在反常色散增益光纤的激光器中能否取得相同的效果,目前还缺乏相关研究。这类激光器输出和演化特性有何特点以及应如何优化等都成为有待解决的问题。对色散管理型含反常... 详细信息

通常自相似脉冲光纤激光器的增益光纤都为正常色散,而利用色散补偿在反常色散增益光纤的激光器中能否取得相同的效果,目前还缺乏相关研究。这类激光器输出和演化特性有何特点以及应如何优化等都成为有待解决的问题。对色散管理型含反常色散增益光纤的锁模激光器进行研究,通过和传统自相似激光系统的分析和对比,指出其完全符合无源自相似激光器特征,并可达到传统正常色散增益光纤构建的无源自相似脉冲激光器的效果。在理论上拓展了自相似脉冲激光器的可实现范围,弥补了传统自相似脉冲激光器在该方面的欠缺。此外,针对该类型激光器系统的色散图、净色散量和色散补偿部分的非线性等方面对输出脉冲的影响进行了详细讨论,为中红外波段使用反常色散增益光纤的激光器产生更高质量的超短脉冲提供了新思路。

关键词：光纤激光器自相似脉冲色散管理中红外波段激光器无源自相似

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单光纤光栅实现窄带全光纤反射器的分析

光电工程 2005年第3期32卷 89-92页

作者：鲁怀伟章宝歌周玲罗冠炜兰州交通大学数理与软件工程学院兰州交通大学光电技术与智能控制教育部重点实验室甘肃兰州730070 兰州交通大学光电技术与智能控制教育部重点实验室

提出了一种由单个光纤光栅和一个光纤方向耦合器组成的新型全光纤反射器,推导出了当光栅为均匀 Bragg 光栅、器件任意端口输入时,任何一端口的输出解析式。分析表明器件具有法布里-珀罗腔干涉仪的特点,耦合器的耦合比系数类似于法布里-... 详细信息

提出了一种由单个光纤光栅和一个光纤方向耦合器组成的新型全光纤反射器,推导出了当光栅为均匀 Bragg 光栅、器件任意端口输入时,任何一端口的输出解析式。分析表明器件具有法布里-珀罗腔干涉仪的特点,耦合器的耦合比系数类似于法布里-珀罗腔的反射率, 耦合比系数越大,输出光谱半高全宽度(FWHM)越窄, 消光比越好。当耦合比系数大于 0.8 时,FWHM 可以窄到0.02nm,消光比大于 0.9。如果光栅是“强”耦合,器件具有均匀分布的多通道梳状输出特性;光栅为“弱”耦合时,则能实现 FWHM 小于 0.02nm 的单频输出。器件只需单个光栅,克服了制作两个完全相同光栅的困难。

关键词：光纤反射器方向耦合器光纤光栅谱线宽度

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三种工况下扩底楔形桩承载特性模型试验研究

岩土力学 2017年第7期38卷 1887-1893页

作者：任连伟顾红伟彭怀风周杨河南理工大学土木工程学院河南焦作454000 河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210098

扩底楔形桩具有单位材料利用率高、竖向桩侧摩阻力和桩端阻力较常规等截面桩高的技术优点。然而,针对该桩型竖向及水平向承载力的定量模型试验研究相对较少。基于模型试验方法,开展砂性土中竖向、水平向荷载以及地面堆载等不同形工况荷... 详细信息

扩底楔形桩具有单位材料利用率高、竖向桩侧摩阻力和桩端阻力较常规等截面桩高的技术优点。然而,针对该桩型竖向及水平向承载力的定量模型试验研究相对较少。基于模型试验方法,开展砂性土中竖向、水平向荷载以及地面堆载等不同形工况荷载作用下扩底楔形桩的承载特性试验,测得不同荷载等级下桩侧摩阻力、桩端阻力、侧向土压力、桩顶下拽位移以及桩身下拽力等分布规律;同时,开展等混凝土用量常规等直径桩的承载特性试验作为对比分析,初步探讨了两种桩型的受力机制与异同点。研究结果表明,试验条件下,扩底楔形桩的单桩竖向承载力约为等直径圆桩的2.33倍,表现出侧阻力和端阻力都优于圆形桩的特点;水平承载力约为等直径圆桩的1.48倍,上部直径较大和扩大头的存在提高了其水平承载性能;与等直径圆桩相比,楔形角的存在可有效降低桩顶下拽位移,可见把传统桩型转变成扩底楔形桩是降低负摩阻力对桩基影响的有效方法之一。

关键词：扩底楔形桩模型试验竖向承载力水平承载力下拽位移

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一种全光纤型窄带梳状滤波器的特性分析

光学技术 2005年第4期31卷 608-610页

作者：鲁怀伟周玲章宝歌罗冠炜兰州交通大学数理与软件工程学院甘肃兰州730070 兰州交通大学光电技术与智能控制教育部重点实验室甘肃兰州730070

分析了由双光纤定向耦合器组成的梳状滤波器的透射特性。根据传输矩阵,推导出了该滤波器的输出光谱与有关参数之间的关系式。分析结果表明:该滤波器具有法布里_珀罗腔多光束干涉的特点,是一种窄带宽梳状滤波器;耦合器的耦合系数与法布里... 详细信息

分析了由双光纤定向耦合器组成的梳状滤波器的透射特性。根据传输矩阵,推导出了该滤波器的输出光谱与有关参数之间的关系式。分析结果表明:该滤波器具有法布里_珀罗腔多光束干涉的特点,是一种窄带宽梳状滤波器;耦合器的耦合系数与法布里_珀罗腔中的反射率类似,通过控制耦合系数可以调节滤波器的通带半宽度、消光比、隔离度、输出光强等。

关键词：应用光学梳状滤波器光纤方向耦合器法布里-珀罗腔

国家重点实验室创新资源捕获过程研究——基于C国家重点实验室的案例剖析

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科技进步与对策 2016年第2期33卷 13-18页

作者：聂继凯危怀安华中科技大学公共管理学院湖北武汉430074

通过对C国家重点实验室创新资源捕获过程的深度剖析,揭示了其信息搜索、评估、关联、附着、引进、消化、吸收、再创新和牵引9个阶段。在此基础上,以资源基础理论、协同创新理论和创新网络理论为支撑,凝练出国家重点实验室创新资源捕获... 详细信息

通过对C国家重点实验室创新资源捕获过程的深度剖析,揭示了其信息搜索、评估、关联、附着、引进、消化、吸收、再创新和牵引9个阶段。在此基础上,以资源基础理论、协同创新理论和创新网络理论为支撑,凝练出国家重点实验室创新资源捕获过程的一般理论模型——SBIP模型,并指出了今后深化研究的重点方向。SBIP模型拓展了相关研究领域,对我国国家实验室通过优化创新资源捕获过程来提升创新能力,具有重要的理论和现实意义。

关键词：国家重点实验室创新资源资源捕获 SBIP模型