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基于Ansys软件的t形密封圈的有限元分析

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橡胶工业 2025年第3期72卷 191-196页

作者：高荣彬黄乐梁火寿高军翔陈晴肖风亮广州国机密封科技有限公司广东广州510535 广州机械科学研究院有限公司广东广州510700

基于Ansys软件,对t形密封圈(由t形橡胶圈和挡圈组成)的结构参数(凸台宽度、台阶高度、凸台高度和外径)对其密封性能(径向力、与轴的接触宽度和接触压力)的影响进行有限元分析。结果表明:在装配状态下,凸台高度是影响t形密封圈的密封性... 详细信息

基于Ansys软件,对t形密封圈(由t形橡胶圈和挡圈组成)的结构参数(凸台宽度、台阶高度、凸台高度和外径)对其密封性能(径向力、与轴的接触宽度和接触压力)的影响进行有限元分析。结果表明:在装配状态下,凸台高度是影响t形密封圈的密封性能的关键结构参数;在加压状态下,凸台宽度和凸台高度是影响t形密封圈的密封性能的关键结构参数。

关键词： t形密封圈结构参数密封性能有限元分析

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中国银矿床类型、时空分布与找矿远景

岩石学报 2025年第2期41卷 383-415页

作者：秦克章韩日回凯旋李真真阚靖王乐高燊赵俊兴岩石圈演化与环境演变全国重点实验室中国科学院地质与地球物理研究所北京100029 中国科学院大学地球与行星科学学院北京100049 中国地质调查局沈阳地质调查中心沈阳110034 河北省地震动力学重点实验室防灾科技学院地球科学学院三河065201 青岛海洋科技中心海洋矿产资源评价与探测技术功能实验室青岛海洋地质研究所青岛266237 中国地质大学(北京)地球科学与资源学院北京100083

我国银矿床分布广泛,矿床成因类型多。近些年来,一些大型-超大型银矿床的相继发现,改写了我国银资源的分布格局。因此亟需对我国银矿床主要成因类型及时空分布规律进行系统总结与研究。本文经过系统整理,梳理出我国77座中型以上(>200t)... 详细信息

我国银矿床分布广泛,矿床成因类型多。近些年来,一些大型-超大型银矿床的相继发现,改写了我国银资源的分布格局。因此亟需对我国银矿床主要成因类型及时空分布规律进行系统总结与研究。本文经过系统整理,梳理出我国77座中型以上(>200t)的银多金属矿床的基本信息与要素,将我国银矿床划分为浅成低温热液型、斑岩型、矽卡岩型、VMS型、SEDEX型、MVt型、沉积型和风化型(红土型)等八种类型,其中以浅成低温热液型最为主要。中国银矿床主要形成于中生代,尤其是晚侏罗世-早白垩世,空间上划分出兴蒙、华北、秦岭-东昆仑、华南、西藏-三江等五个银成矿省。银成矿省成因与陆壳类型(古老和新生地壳)、伸展构造背景和大规模中酸性岩浆活动密切相关。综合上述因素,兴蒙复合造山带仍然是具有巨大找矿潜力的成矿区。那更康切尔沟银多金属矿床的发现表明东昆仑(原特提斯-新特提斯)叠合造山带地区具有很好的找矿潜力。三江复合造山带在银锡矿床的勘查方面亦潜力巨大。

关键词：中国银矿床成因类型地质特征时空分布银成矿省找矿前景

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A thorough analysis of the effect of surfactant/s on the solubility and pharmacokinetics of (S)-zaltoprofen

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Asian Journal of Pharmaceutical Sciences 2019年第4期14卷 435-444页

作者： cuong Viet Pham Jong-Suep Baek Jong-Hun Park Sang-Hun Jung Jong-Seong Kang Cheong-Weon Cho College of Pharmacy and Institute of Drug Research and Development Chungnam National UniversityDaejeon 34134Republic of Korea Department of Herbology College of Korean MedicineDongguk UniversityGyeongju 38066Republic of Korea

Until now, there are no publications about the preformulation studies on(S)-zaltoprofen((S)-ZPF). Hence, we first investigated the solubility of(S)-ZPF, screened solubilizers and performed the pharmacokinetic study of(S)-ZPF in the presence of the solubilizers. the measurement of the solubility of(S)-ZPF in 26 different solvents was carried out, including d-alpha tocopheryl polyethylene glycol 1000 succinate(tPGS), 2-hydroxypropyl-β-cyclodextrin(HPCD), and mixtures of individual solvent. the plasma concentration of(S)-ZPF and the amount of(S)-ZPF retained in stomach were determined after oral(35.0 mg/kg) and intravenous(5.0 mg/kg) administration. the solubility of(S)-ZPF showed an increase of 484-fold in tPGS compared to its aqueous solubility. there was a significant increase of AUC 0-24 h for pure(S)-ZPF in the tPGS group(813.59 ± 64.17 μg h/ml) in comparison with AUC 0-24 h in the HPCD group(595.57 ± 71.76 μg h/ml) and water group(465.57 ± 90.89 μg h/ml). In addition, the t max of(S)-ZPF in the tPGS group was 2 h, much faster than that in the HPCD or water groups(5.50 or 5.67 h, respectively). this suggested that tPGS played a significant role in the increase of solubility and bioavailability of(S)-ZPF.

关键词： (S)-zaltoprofen Solubility Bioavailability D-alpha tocopheryl polyethylene glycol 1000 succinate 2-hydroxypropyl-β-cyclodextrin

MBDA R&t EFFORt ON PULSED AND CONtINUOUS DEtONAtION WAVE ENGINES

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transactions of Nanjing University of Aeronautics and Astronautics 2011年第1期28卷 12-22页

作者： Falempin Francois le Naour Bruno MBDA导弹系统公司未来飞行器动力部

the continuous detonation wave engine（CDWE）can be considered to reduce the environmental conditions generated by pulsed detonation engine（PDE）while reducing the importance of initiation issue and simplifying some integration *** experimental programs are performed by MBDA and Lavrentiev Institute to study CDWE operating mode and to address some key points for the feasibility of an operational rotating wave engine for space *** is found that such engine can deliver impressive thrust in a very small package（275 daN for internal diameter of 50 mm and length of 100 mm,kerosene-oxygen engine）and that can be increased with the use of a diverging *** to the geometry of the combustion chamber,a plug or aerospike nozzle seems to be the best design,the thrust vectoring capability of this engine（with the local change of the mass flow rate）being a way to solve the problem of attitude *** heat fluxes are very high but located mostly near the injection *** point will help the gasification of the liquid component injected inside the combustion *** preliminary tests are performed to evaluate the capability of C/SiC composite materials to sustain the very severe mechanical environment generated by the rotating detonation *** these first steps,a large scale ground demonstrator allowing to address all issues for a continuous detonation rocket engine using LH2/LOx mixture is designed by *** the first step toward the development of this large scale engine,a small scale demo is tested in Spring 2010.

关键词： detonation wave engine propulsion performance model

Survey of current retinopathy of prematurity practices in China

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International Journal of Ophthalmology(English edition) 2021年第8期14卷 1241-1247页

作者： thao Phuong le Jing Feng leona Ding Rong Hu Xiao-Bo Lou J Niklas Ulrich Michelle t Cabrera Eye Associates Northwest P.C. SeattleWashington 98104-1306USA Department of Ophthalmology Beijing Chaoyang HospitalCapital Medical UniversityBeijing 100020China Department of Ophthalmology University of WashingtonSeattleWA 98195-0005USA Department of Ophthalmology Hunan People’s HospitalChangsha 410005Hunan ProvinceChina Department of Ophthalmology University of North CarolinaChapel HillNC 27515USA Department of Ophthalmology Seattle Children’s HospitalSeattleWA 98105USA

AIM:to understand retinopathy of prematurity(ROP)screening and treatment preferences among Chinese ***:A Chinese language survey was administered anonymously using Web Q(Catalyst,Seattle,WA,USA)among Chinese ROP screeners from December 2016 to January ***:Among 70 ophthalmologists contacted,65 responded(93%;78%female,mean age 40 y,57%pediatric ophthalmologists and 25%retina specialists).Most used screening criteria of birth weight≤2 kg(62%)with variation in cut-off gestational age(≤37 wk,34%;≤34 wk,22%;≤32 wk,31%).Ret Cam(Natus Medical Incorporated,Pleasanton,CA,USA)wide-field fundus photography assisted most screeners(72%)and was exclusively used by many(29%).Among 55 ophthalmologists treating ROP,anti-vascular endothelial growth factor(VEGF)was preferred over laser for both zoneⅠ(76%vs 24%)and zoneⅡROP(58%vs 42%).Retina specialists(P=0.004)and ophthalmologists with>3 mo of training(P=0.03)were more likely to use antiVEGF over laser for zoneⅠ*** of laser training(8/20,40%),access(6/20,30%)and anesthesia(4/20,20%)were common barriers to laser ***:Chinese ROP screeners favor antiVEGF injection and Ret Cam imaging for ROP management.A better understanding of ROP screening and treatment informs future research and education efforts in China.

关键词： pediatrics retina retinopathy of prematurity survey telemedicine

Stem cell-based therapy for human diseases

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Signal transduction and targeted therapy 2022年第9期7卷 3242-3282页

作者： Duc M.Hoang Phuong t.Pham trung Q.Bach Anh t.L.Ngo Quyen t.Nguyen trang t.K.Phan Giang H.Nguyen Phuong t.t.le Van t.Hoang Nicholas R.Forsyth Michael Heke Liem thanh Nguyen Department of Research and Development Vinmec Research Institute of Stem Cell and Gene TechnologyVinmec Healthcare SystemHanoiVietnam Department of Cellular therapy Vinmec High.Tech CenterVinmec Healthcare SsystemHanoiVietnam Institute for Science&technology in Medicine Keele UniversityKeeleUK a Department of Biology Stanford UniversityStanfordCAUSA

Recent advancements in stem cell technology open a new door for patients suffering from diseases and disorders that have yet to be *** cell-based therapy,including human pluripotent stem cells(hPsCs)and multipotent mesenchymal stem cells(MSCs),has recently emerged as a key player in regenerative *** are defined as self-renewable cell types conferring the ability to differentiate into various cellular phenotypes of the human body,including three germ *** are multipotent progenitor cells possessing self-renewal ability(limited in vitro)and differentiation potential into mesenchymal lineages,according to the International Society for Cell and Gene therapy(ISCt).this review provides an update on recent clinical applications using either hPSCs or MSCs derived from bone marrow(BM),adipose tissue(At),or the umbilical cord(UC)for the treatment of human diseases,including neurological disorders,pulmonary dysfunctions,metabolic/endocrine-related diseases,reproductive disorders,skin burns,and cardiovascular ***,we discuss our own clinical trial experiences on targeted therapies using MsCs in a clinical setting,and we propose and discuss the MSC tissue origin concept and how MSC origin may contribute to the role of MSCs in downstream applications,with the ultimate objective of facilitating translational research in regenerative medicine into clinical *** mechanisms discussed here support the proposed hypothesis that BM-MSCs are potentially good candidates for brain and spinal cord injury treatment,At-MSCs are potentially good candidates for reproductive disorder treatment and skin regeneration,and UC-MsCs are potentially good candidates for pulmonary disease and acute respiratory distress svndrometreatment.

关键词： diseases distress treatment

Optimization of Supercontinuum Sources for Ultra-Broadband t-CARS Spectroscopy

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Chinese Physics letters 2011年第3期28卷 78-80页

作者： LIU Xing LIU Wei YIN Jun QU Jun-le LIN Zi-Yang NIU Han-Ben Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Optoelectronic EngineeringShenzhen UniversityShenzhen 518060 College of Precision Instrument and Optoelectronics Engineering Tianjin UniversityTianjin 300072

For a typical photonic crystal fiber with two zero-dispersion wavelengths,we theoretically demonstrate a new way to generate supercontinuum using an input pulse of 30fs duration and lOkW peak power for providing a compact and cost effective light source to the ultra-broadband time-resolved coherent anti-Stokes Raman scattering spectroscopy.

关键词： spectroscopy continuum coherent

Genotoxic effects of microcystins mediated by nitric oxide and mitochondria

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Journal of Environmental Sciences 2015年第5期27卷 206-208页

作者： Qingqing Liu X.Chris le Division of Analytical and Environmental toxicology Department of Laboratory Medicine and Pathology 10-102 Clinical Sciences BuildingUniversity of AlbertaEdmonton Alberta T6G 2G3 Canada

Microcystins are potent toxins,produced naturally by cyanobacteria（blue green algae）,and they present significant threats to human and animal health（WHO,1999;Chorus,2001;Carmichael et al.,2001;Falconer,2005;IARC,20... 详细信息

关键词： Microcystin-LR Nitric oxide(NO) Mitochondria Chronic exposure Genotoxicity Cyanobacteria Blue green algae Natural toxins

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家马驯化史更迭

环球科学 2025年第1期 34-43页

作者：威廉·t.泰勒徐媛(翻译) 美国科罗拉多大学博尔德分校西北农林科技大学

新的考古学和遗传学发现颠覆了人们长期以来关于马驯化的认识。我们生活在一个马背上建立的世界。虽然如今人们很少会接触到马,但就在几十年前,全球的社会联系都是依靠家马维系的。那时,人们日常生活的方方面面都与马密不可分:邮差骑马... 详细信息

新的考古学和遗传学发现颠覆了人们长期以来关于马驯化的认识。我们生活在一个马背上建立的世界。虽然如今人们很少会接触到马,但就在几十年前,全球的社会联系都是依靠家马维系的。那时,人们日常生活的方方面面都与马密不可分:邮差骑马送信,人们乘坐马车旅行,商人用马将货物运往各大洲,农民用马耕种土地,土兵在战场上骑马厮杀。

关键词：日常生活驯化骑马遗传学考古学