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新修定的化学防护服国家标准解析

纺织学报 2024年第3期45卷 163-168页

作者：杨光杨小兵栗丽姚之凤周川张明明国民核生化灾害防护国家重点实验室北京100191 雾霾健康效应与防护北京市重点实验室北京100191 中国安全生产科学研究院北京100012

为厘清化学防护服国家标准修订后的情况,通过分析我国化学防护服国家标准发展历史,研究国外化学防护服标准,重点针对修订后的GB 24539—2021《防护服装化学防护服》的变化,从化学防护服的分类、性能要求、试验方法等方面对该标准加以解... 详细信息

为厘清化学防护服国家标准修订后的情况,通过分析我国化学防护服国家标准发展历史,研究国外化学防护服标准,重点针对修订后的GB 24539—2021《防护服装化学防护服》的变化,从化学防护服的分类、性能要求、试验方法等方面对该标准加以解读。分析发现:GB 24539—2021将相关标准进行整合,对化学防护服的分类进行了较大的调整和更新,删除了非气密型化学防护服-ET,增加了气密型化学防护服、有限泼溅化学防护服和织物酸碱类化学防护服;相应地,性能要求也产生了较大变化,主要包括服装整体防护性能、服装面料防护性能及服装面料理化性能;GB 24539—2021中的大部分试验方法沿用了之前相关标准中的试验方法,但也进行了相应的改进和完善,主要包括试样预处理条件和试验环境条件、化学防护服向内泄漏率测试方法、化学防护服液密性能测试方法、化学防护服面料耐磨损性能测试方法和耐屈挠破坏性能测试方法。

关键词：国家标准防护服装化学防护服防护性能耐磨损性能

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水中旋转圆盘振动阻尼测量与模拟

北京理工大学学报 2024年第4期44卷 377-385页

作者：姚志峰刘宝熙曾永顺白绵绵王福军中国农业大学水利与土木工程学院北京100083 清华大学能源与动力工程系北京100084 陕西省水利电力勘测设计研究院陕西西安710001 北京市供水管网系统安全与节能工程技术研究中心北京100083

为了研究模态做功法在计算旋转式机械水力阻尼时的适用性和准确性,利用旋转圆盘阻尼测量系统的实验数据对该方法做了评估.研究表明,圆盘的水力阻尼值随转速的增加呈现下降的趋势;利用模态做功法计算水力阻尼值时必须考虑旋转效应带来的... 详细信息

为了研究模态做功法在计算旋转式机械水力阻尼时的适用性和准确性,利用旋转圆盘阻尼测量系统的实验数据对该方法做了评估.研究表明,圆盘的水力阻尼值随转速的增加呈现下降的趋势;利用模态做功法计算水力阻尼值时必须考虑旋转效应带来的影响,如果直接使用静止条件下的模态结果,水力阻尼随转速的变化规律将完全和实验结果相反;在考虑旋转的条件下,计算精度有所提高,但整体呈现过预测的问题,该方法对旋转结构阻尼特性的预测精度还有待提高.

关键词：圆盘旋转振动模态做功水力阻尼

Dosimetry of chimeric TNT in lung tumor patients

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Nuclear Science and Techniques 2007年第4期18卷 227-231页

作者： CHEN Yangchun CHEN Shaoliang JU Dianwen SHI Hongcheng yao zhifeng Nuclear Medicine Department Zhongshan Hospital Fudan University Shanghai200032 China PET/CT Center of the First Affiliated Hospital of Guangzhou Medical College Guangzhou 510230 China Shanghai MediPharm Biotech Co Ltd Shanghai 201203 China

The purpose of this study was to assess the absorbed dose of tumor and main critical organs in 131I labeled chimeric tumor necrotic treatment (chTNT). In 9 patients, a single intravenous dose of (29.6±3.7) MBq/kg was administered. Blood samples were drawn at different time intervals, and urine was collected for up to one week. Tissue distribution of 131I-chTNT was followed for up to one week by gamma camera imaging. Absorbed doses to the whole body and to normal organs were computed according to the MIRD scheme using Mirdose-3 software. S-factors for lung tumors were estimated by comparison with lungs of similar mass and position in the body. It was found that mean serum disappearance half time values for 131I-chTNT were (4.93±9.36) h and (61.7±21.2) h for α, β respectively, while that for whole body was(99±10) h. Mean urine biological clearance half time value was (90±10) h. The absorbed dose to tumor was (8.28±2.65) Gy, and the tumor-to-nontumor dose ratio was 3.95±1.55. And the mean effective dose to patients was (1.02±0.29) mSv/MBq.

关键词：肺癌放射疗法放射量碘放射性同位素

A general alternate loading technique and its applications in the inverse designs of centrifugal and mixed-flow pump impellers

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Science China(Technological Sciences) 2021年第4期64卷 898-918页

作者： WANG ChaoYue WANG FuJun AN DongSen yao zhifeng XIAO RuoFu LU Li HE ChengLian ZOU ZhiChao College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System Beijing 100083China China Institute of Water Resources and Hydropower Research Beijing 100038China China Water Resources Beifang Investigation Design and Research Co.Ltd.Tianjin 300222China

For the inverse designs of centrifugal and mixed-flow pump impellers,clarifying the generation process of secondary flows and putting forward corresponding suppression measures is an important approach to improve the impeller *** this paper,to provide a better qualitative insight into the generation mechanism of secondary flows in the impeller,a simple kinematic equation is derived based on the ideal assumptions,which indicates that the potential rothalpy gradient(PRG)is the most important dynamic source that actively induces secondary vortical *** by the natural adverse PRG on the S1 and S2 stream surfaces,two typical secondary flows,H-S and P-S secondary flows,are clearly *** specially suppress these typical secondary flows,a general alternate loading technique(GALT)is proposed,aiming to adjust the real blade loadingδp to control the PRG *** the blade fore part,theδp on the hub streamline should be slowly increased to avoid breakneck growth of the potential rothalpy to reduce adverse streamwise PRG on the S2 *** the blade middle part,theδp should be moderately decreased to reduce adverse streamwise PRG on the S1 *** the blade aft part,the difference in theδp between the shroud and hub streamlines should be decreased faster to control the exit *** applying the GALT to the impeller designs of three typical pump types in hydraulic engineering,the organizational effect of the PRG on fundamental flow structures is *** GALT can effectively control the PRG distributions and suppress the secondary flows,thereby widening the pump’s high-efficiency zone,improving flow uniformity and suppressing pressure *** with the current Z-G method and the ALT,the GALT can meet the requirements of"de-experience"better,thereby enabling the designers to obtain good products explicitly and quickly.

关键词： alternate loading technique inverse design centrifugal pump mixed-flow pump impeller potential rothalpy gradient

High nitrogen stainless steel drug-eluting stent-Assessment of pharmacokinetics and preclinical safety in vivo

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Bioactive Materials 2020年第4期5卷 779-786页

作者： Shanshan Chen zhifeng yao Yongbiao Guan Hui Yang M.Babar Shahzad Yizhe Wu Bingchun Zhang Li Shen Ke Yang Institute of Metal Research Chinese Academy of Sciences72 Wenhua RoadShenyang110016China Shanghai Institute of Cardiovascular Diseases Department of CardiologyZhongshan HospitalFudan University180 Fenglin RoadShanghai200032China National Beijing Center for Drug Safety Evaluation and Research Beijing Institute of Pharmacology and ToxicologyAcademy of Military Medical Sciences27 Taiping RoadHaidian DistrictBeijing100850People's Republic of China

Pharmacokinetic analyses were performed using 20 pigs for 120-days implantation,while one sirolimus-eluting stent was implanted into one of their coronary *** different time points,the residual sirolimus on the stent,delivered locally(to artery wall),regionally(to adjacent and downstream muscle)and systemically(to plasma and visceral organs),was detected throughout 120 *** safety evaluation was performed using 32 pigs for 180-days implantation to study the safety of metal platform material and the effectiveness of sirolimus eluting coating on the HNS *** neointima area,restenosis rate and inflammatory grade for HNS and control group stents were detected and *** 80%sirolimus was eluted from the sirolimuseluting stents after 30-days implantation in ***,there was sustained sirolimus in the artery wall,cardiac muscle and heart throughout 120-days implantation,and sirolimus accumulated to the peak at 90-days *** was inferred that the sirolimus eluting stent in this study was covered by neointima before 90-days implantation,indicating that the sirolimus eluting coating on the HNS stent was safe and *** little sirolimus was distributed in visceral organs after 14-days *** sirolimus-eluting stent exhibited lower restenosis rate and lower inflammatory grade than control group,which verified that the sirolimus-eluting coating design in this study was reasonable and *** addition,there were no significant difference in restenosis rate and inflammatory score between HNS bare-metal stent and drug-eluting stents,illustrating that HNS has good bio-compatibility and is suitable to use as coronary artery stent material.

关键词： Sirolimus-eluting stent Pharmacokinetics Preclinical safety Tissue response

Experimental study of piperlongumine inducing apoptosis of human breast adenoma MDA-MB-231 cells

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The Chinese-German Journal of Clinical Oncology 2013年第7期12卷 319-325页

作者： zhifeng yao Jianxin yao Xia He Zhanfeng Li Yongbiao Liu Department of Radiation Oncology The First Affiliated Hospital of Nanjing Medical University Department of Medical Imaging Nanjing Health School of Jiangsu Union Technical Institute Department of Radiation Oncology The Affiliated Cancer Hospital of Nanjing Medical University

Objective： The aim of the study was to investigate the apoptosis induced by piperlongumine on human breast adenoma MDA-MB-231 cells and the mechanism involved. Methods： Human breast adenoma MDA-MB-231 cells line was cultured in vitro. The inhibitory effect of piperlongumine on the proliferation of human breast adenoma MDA-MB-231 cells was measured by CCK-8 assay. Distribution of cell cycle was analyzed by flow cytometry. The apoptosis rates of MDA-MB- 231 cells were measured using Annexin V/PI staining. The flow cytometry with the probe of DCFH-DA was used to detect the intracellular reactive oxygen species levels. Western blot was used to explore the protein expression of Bcl-2 and Bax. Results： The CCK-8 assay showed that piperlongumine had an inhibiting effect on the proliferation of MDA-MB-231 cells in a concentrationand time-dependent manner. MDA-MB-231 cells were markedly arrested at G0/G1 phase after treatment of piperlongumine. Piperlongumine induced apoptosis of MDA-MB-231 cells obviously. The level of intracellular reactive oxygen species was increased in a dose-dependent manner. The antioxidant N-acetyI-L-cystein inhibited the apoptosis of cells and the level of intracellular reactive oxygen species was also decreased. By Western blot analysis, we found the expression of Bax was up-regulated whereas that of Bcl-2 was down-regulated in a concentration-dependent manner. Conclusion： PiperIongumine possesses a significant function for inhibiting proliferation, arresting cells at G0/G1 phase and inducing apoptosis of MDA-MB-231 cells, which seems to be associated with the increased generation of intracellular reactive oxygen species as well as the down-regulation of Bcl-2 and up-regulation of Bax.

关键词： piperlongumine (piplartine, PL) human breast adenoma cells cell cycle apoptosis reactive oxygen species Bax Bcl-2

Combining anodic alcohol oxidative coupling for C-C bond formation with cathodic ammonia production

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National Science Review 2024年第5期11卷 217-226页

作者： Leitao Xu Wei Chen Cairong Wang Wenjie Wu Yelin yao zhifeng Huang Jingcheng Wu Ming Yang Yandong Wu Dianke Xie Yuqin Zou Shuangyin Wang State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringAdvanced Catalytic Engineering Research Center of the Ministry of Education Hunan University

Electrocatalytic oxidation of alcohols using heterogeneous catalysts is a promising aqueous, energy-efficient and environmentally friendly approach, especially for coupling different alcohols to prolong the carbon chain via co-oxidation. Precisely regulating critical steps to tailor electrode materials and electrolyte composition is key to selectively coupling alcohols for targeted synthesis. However, selectively coupling different alcohols remains challenging due to the lack of effective catalyst and electrolyte design promoting specific pathways. Herein, we demonstrate a paired electrolysis strategy for combining anodic oxidative coupling of ethanol（EtOH） and benzyl alcohol（PhCH2OH） to synthesize cinnamaldehyde（CAL） and cathodic ammonia production. The strategies involve:（i） utilizing the salt-out effect to balance selective oxidation and coupling rates;（ii） developing platinum-loaded nickel hydroxide electrocatalysts to accelerate intermediate coupling kinetics;（iii） introducing thermodynamically favorable nitrate reduction at the cathode to improve coupling selectivity by avoiding hydrogenation of products while generating valuable ammonia instead of hydrogen. We achieved 85% coupling selectivity and 278 μmol/h NH3productive rate at 100 m A/cm2with a low energy input（～1.63 V）. The membrane-free, low energy, scalable approach with a wide substrate scope highlights promising applications of this methodology. This work advances heterogeneous electrocatalytic synthesis through rational design principles that integrate anodic oxidative coupling with cathodic nitrate reduction reactions, having synergistic effects on efficiency and selectivity.

关键词： anodic alcohol oxidative coupling C–C bond formation cinnamaldehyde cathodic ammonia production

无创左室压力应变曲线在冠心病心肌缺血诊断中的价值

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中国临床医学 2024年第3期31卷 411-419页

作者：赵盈洁何芙蓉何玮过伟锋赵士海葛振一姚志锋陈海燕潘翠珍舒先红上海市影像医学研究所上海200032 复旦大学附属中山医院心脏超声诊断科上海200032 复旦大学附属中山医院心内科上海200032 复旦大学基础医学院上海200032 复旦大学附属中山医院血管外科上海200032 复旦大学附属中山医院放射科上海200032

目的以冠状动脉血流储备分数(fraction flow reservation,FFR)为金标准,采用无创左室压力应变环(pressure strain loop,PSL)评价心肌做功相关参数对冠状动脉粥样硬化性心脏病(coronary artery disease,CAD)心肌缺血的诊断价值。方法前... 详细信息

目的以冠状动脉血流储备分数(fraction flow reservation,FFR)为金标准,采用无创左室压力应变环(pressure strain loop,PSL)评价心肌做功相关参数对冠状动脉粥样硬化性心脏病(coronary artery disease,CAD)心肌缺血的诊断价值。方法前瞻性纳入2020年12月至2021年12月在复旦大学附属中山医院就诊的53例临床疑似CAD患者,均进行超声心动图检查、有创冠状动脉造影和FFR测量。根据冠脉造影结果将患者分为心肌缺血组(FFR≤0.8,24例)和非心肌缺血组(FFR>0.8,29例)。采用PSL进行脱机分析,获得左室整体做功指数(global work index,GWI)、整体有效功(global constructive work,GCW)、整体无效功(global wasted work,GWW)、整体做功效率(global work efficiency,GWE)、整体正向功(global positive work,GPW)及整体收缩期有效功(global systolic constructive work,GSCW)等心肌做功参数值,进行两组间比较。采用ROC曲线分析心肌做功参数对心肌缺血的诊断效能。结果在18、16和12节段水平,与非心肌缺血组相比,心肌缺血组GWI、GCW、GPW、GSCW均降低(P<0.001)。ROC曲线显示,GWI、GCW、GPW、GSCW在18节段水平AUC分别为0.803(95%CI 0.679~0.927)、0.807(95%CI 0.687~0.928)、0.822(95%CI 0.708~0.936)、0.819(95%CI 0.703~0.935)。其中,GWI最佳截断值为1676.3 mmHg%,预测心肌缺血的灵敏度、特异度和准确度分别为70.8%、86.2%和79.2%;GCW最佳截断值为1999.4mmHg%,预测心肌缺血的灵敏度、特异度和准确度分别为75.0%、82.8%和79.2%。结论采用PSL分析心肌做功对CAD心肌缺血人群有较好的筛查作用。

关键词：超声心动图压力应变环血流储备分数冠心病心肌缺血

小麦条锈病菌夏孢子显微图像远程采集系统设计与试验

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农业机械学报 2018年第11期49卷 39-47页

作者：雷雨姚志凤何东健西北农林科技大学机械与电子工程学院陕西杨凌712100 农业农村部农业物联网重点实验室陕西杨凌712100 陕西省农业信息感知与智能服务重点实验室陕西杨凌712100

利用孢子捕捉器捕捉小麦田间空气中的条锈病菌夏孢子已成为当前小麦条锈病预测预报的重要手段。针对现有的孢子捕捉设备效率低、费时费力、需人工定时换取载玻片或捕捉带等问题,基于ARK-1123C型嵌入式工控机和显微镜CCD数字摄像头,提出... 详细信息

利用孢子捕捉器捕捉小麦田间空气中的条锈病菌夏孢子已成为当前小麦条锈病预测预报的重要手段。针对现有的孢子捕捉设备效率低、费时费力、需人工定时换取载玻片或捕捉带等问题,基于ARK-1123C型嵌入式工控机和显微镜CCD数字摄像头,提出了一种高放大倍数、高分辨率的小麦条锈病菌夏孢子显微图像远程采集系统的设计方案。设计了系统的硬、软件结构,实现了自动取载玻片、涂脂、空中孢子捕捉、孢子显微图像采集、载玻片回收等一系列功能,且可根据用户需求远程设置孢子捕捉和显微图像采集参数,采集的图像通过无线网络传输到远程服务器中。为了验证系统的性能,在小麦田间进行了40 d的系统综合试验测试。测试结果表明,系统可长时间稳定工作,能够远程实时采集放大400倍的4 096像素×3 288像素的夏孢子显微图像。该系统能够实时采集和远程传输小麦条锈病菌夏孢子显微图像,可满足野外小麦田间空气中夏孢子监测的需求,为农田空气中小麦条锈病菌夏孢子的自动计数及条锈病的预测预报提供重要技术支持。

关键词：小麦条锈病夏孢子显微图像远程采集系统