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基于声子晶体的高速列车地板支撑层隔声研究

噪声与振动控制 2024年第1期44卷 220-225,233页

作者：李海萍曹兴潇石广田张晓芸宋杲张小安兰州交通大学机电工程学院兰州730070 兰州交通大学甘肃省轨道交通服役环境与智能运维重点实验室兰州730070

随着高速列车运营速度不断提高,轨道交通产生的振动噪声会严重影响列车的车内声环境,进而降低乘坐舒适性,因此针对列车噪声源部位的车体隔声设计至关重要。目前的隔声措施能够有效控制车内中高频噪声,而对于低频噪声的抑制效果还有待进... 详细信息

随着高速列车运营速度不断提高,轨道交通产生的振动噪声会严重影响列车的车内声环境,进而降低乘坐舒适性,因此针对列车噪声源部位的车体隔声设计至关重要。目前的隔声措施能够有效控制车内中高频噪声,而对于低频噪声的抑制效果还有待进一步提升。声子晶体是一种具有弹性波带隙的周期性结构材料,该结构不需要大尺寸即可在局域共振作用下形成低频带隙,进而抑制弹性波的传播从而起到低频降噪作用。基于声子晶体周期性理论,以车辆转向架部位地板的木骨支撑层为对象,研究声子晶体在木骨支撑层隔声中的应用,系统分析声子晶体结构的带隙特性和隔声特性以及基于声子晶体结构的支撑层隔声性能。研究结果表明:通过改变结构形式及其参数可实现对于声子晶体结构的带隙形成频带及其隔声特性的人为设计和控制;以高速列车地板中的木骨结构为对象,结合声子晶体理论将其设计为木骨和声子晶体组合结构形式,不仅能够保持声子晶体在0~220 Hz低频段和620~710 Hz频段优越的隔声性能,同时可极大提升220~620 Hz频段的隔声性能;既维持该层结构的支撑作用,又能很好提升隔声性能,在高速列车地板设计中具有很强的有效性和适用性。

关键词：声学轨道交通车辆低频噪声控制声子晶体带隙特性隔声特性

Studies on the motion and radiation of interior plasmas in gas-filled hohlraums with different laser entrance hole sizes

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Plasma Science and Technology 2024年第7期26卷 40-47页

作者：郭亮李欣李琦李三伟胡昕李晋邓博邓克立王强强曹柱荣侯立飞车兴森杜华冰徐涛何小安李志超蒋小华蒋炜郑春阳郑无敌宋鹏丁永坤杨冬杨家敏 Research Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900People’s Republic of China Institute of Applied Physics and Computational Mathematics Beijing 100088People’s Republic of China

An experiment on 100 k J laser facility is performed to study the motive features and radiation properties of plasmas from different areas inside gas-filled cylindrical hohlraums.These hohlraums are designed to possess one open end and one laser entrance hole(LEH)with different diameters,which would or not result in the blocking of the LEH.An x-ray streak camera that is set at 16 degrees with respect to the hohlraum axis is applied to acquire the timeresolved x-ray images from the open end.Based on the images,we can study the evolutions of the wall plasma,corona bubble plasma and LEH plasma simultaneously through an equivalent view field of hohlraum interior.Multi-group flat response x-ray detectors are applied to measure the x-ray fluxes.In order to understand these characteristics,our two-dimensional radiation hydrodynamic code is used to simulate the experimental results.For the accuracy of reproduction,dielectronic recombination and two parameter corrections are applied in our code.Based on the comparison between experiments and simulations,we quantitatively understand the blocking process of LEH and the motion effects of other plasmas.The calibrated code is beneficial to design the gas-filled hohlraum in a nearby parameter space,especially the limit size of LEH.

关键词： gas-filled hohlraum plasma expansion LEH blocking

iRoot SP单尖法根管充填后桩道预备时机对根尖封闭效果的影响

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口腔材料器械杂志 2024年第1期33卷 9-13页

作者：牛雪微容晓安王爽曹天翼孙汉堂南通市口腔医院牙体牙髓病科南通226000

目的研究iRootSP单尖法根管充填后不同桩道预备时机对根尖封闭效果的影响。方法收集单根管离体牙75枚,截冠,随机分9组,其中A1、A2、A3组采用AH-Plus+热牙胶充填,;B1、B2、B3组采用iRoot SP+单尖根充;A4组热牙胶根充;B4组单尖根充;C组只... 详细信息

目的研究iRootSP单尖法根管充填后不同桩道预备时机对根尖封闭效果的影响。方法收集单根管离体牙75枚,截冠,随机分9组,其中A1、A2、A3组采用AH-Plus+热牙胶充填,;B1、B2、B3组采用iRoot SP+单尖根充;A4组热牙胶根充;B4组单尖根充;C组只预备不充填。A1和B1组立即预备桩道,而A2和B2组则1周后延迟进行,A3、B3、A4、B4组不进行桩道预备。A4组和B4组为阳性对照组,C组为阴性对照组,运用染料微渗漏实验及扫描电镜观察评价根尖区微渗漏情况。结果各实验组及阳性对照组的染料均渗透入根尖,渗透深度分别为A1:(1.14±0.40)mm;A2:(1.32±0.14)mm;A3:(0.61±0.15)mm;A4:(4.75±0.16)mm;B1:(1.07±0.17)mm;B2:(1.22±0.19)mm;B3:(0.52±0.15)mm;B4:15 mm;C:0 mm。比较染料渗透深度,其中A1组与A3组、B1组与B3组、A2组与A3组、B2组与B3组间差异具有统计学意义(P0.05)。iRootSP封闭性与AH-Plus相似,iRootSP单尖法充填后即刻、延迟桩道预备后根尖封闭性相似。结论iRoot SP单尖法根管充填与AH-Plus热牙胶连续波垂直加压根充比较,其根尖封闭效果相似,即刻、延迟桩道预备对iRoot SP单尖法根管充填根尖封闭效果无影响。

关键词： iRoot SP 桩道预备封闭单尖充填技术

山羊地方性鼻内肿瘤病毒TaqMan荧光定量RT-PCR检测方法的建立及应用

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畜牧兽医学报 2024年第5期55卷 2259-2266页

作者：李鹏飞高桂琴周广青吴锦艳颜新敏曹小安何继军袁莉刚尚佑军甘肃农业大学动物医学院兰州730070 中国农业科学院兰州兽医研究所动物疫病防控全国重点实验室兰州730046 白银市农业综合行政执法队白银730900

山羊地方性鼻内肿瘤(enzootic nasal tumor, ENT)是山羊的病毒性传染病,由山羊地方性鼻内肿瘤病毒(enzootic nasal tumor virus of goats, ENTV-2)所引起,感染后可以导致山羊的鼻道筛骨上皮细胞发生不可逆的癌变,已在世界范围内广泛存在... 详细信息

山羊地方性鼻内肿瘤(enzootic nasal tumor, ENT)是山羊的病毒性传染病,由山羊地方性鼻内肿瘤病毒(enzootic nasal tumor virus of goats, ENTV-2)所引起,感染后可以导致山羊的鼻道筛骨上皮细胞发生不可逆的癌变,已在世界范围内广泛存在,对山羊养殖业造成严重的经济损失。为建立快速、准确且能定量分析ENTV-2的检测方法,本研究根据GenBank上发布的ENTV-2 env基因(MT254061.1)保守区域设计引物和TaqMan探针,建立ENTV-2 TaqMan探针荧光定量RT-PCR检测方法,并对其特异性、灵敏性、重复性与临床检测效果进行验证。结果显示,重组质粒标准品模板浓度为6.30×10^(2)~6.30×10^(7) copies·μL^(-1)呈现良好的线性关系,相关系数R^(2)为0.996 5,扩增效率为110%,线性方程的斜率为-2.953,最低检测限度为6.30×10^(1) copies·μL^(-1);组内变异系数和组间变异系数均小于2%,重复性好;与口蹄疫病毒((foot-and-mouth disease virus, FMDV)、小反刍兽疫病毒(peste des petits ruminants virus, PPRV)、蓝舌病毒(bluetongue virus)、羊内源性逆转录病毒(endogenous retroviruses)等均无交叉反应,表明该方法具有很好的特异性。利用本研究所建立的TaqMan探针实时荧光定量RT-PCR检测方法对29份临床样品进行检测,该方法较普通PCR方法的检出率更高。综上表明,本研究成功建立了ENTV-2 TaqMan探针实时荧光定量RT-PCR检测方法,为ENTV-2的快速诊断和流行病学调查提供技术手段。

关键词：山羊地方性鼻内肿瘤病毒羊内源性逆转录病毒 TaqMan 荧光定量RT-PCR

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Co-expression of Clostridium perfringens α and ε Toxins and Their Immunogenicity

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Animal Husbandry and Feed Science 2015年第2期7卷 74-77页

作者： Han Guangwei Li Zhaocai Gong Xiaowei Chen Qiwei cao xiaoan Zheng Fuying Zhang Xiaoying Zhou Jizhang State Key Laboratory of Veterinary Etiological Biology / Lanzhou Veterinary Research Institute Chinese Academy of Agricultural Science Lanzhou Animal Health Inspection Institute

The genc CPA and ETX encoding α and e toxins were amplified from the standard strain C60-2 of type D Clostridium perfingens by PCR, and then they were inserted into pet-Duct-1 vecto, respectively for the construction of co-expression plasmid pETDoet-1-CPA-ETX. The co-expression plasmid was transformed into BL21 （DE3） competent cells, at and e toxins proteins were induced by IPTG before analysis by SDS-PAGE. As a result, both of α and e toxins were detected at 43 and 34 KU by western-blot. Mice immunized with the co-expressed α and e toxins proteins produced high titers of neutralizing antibodies in the serum, which protected the mice against the attack of type D C. perfringens culture filtrate. In addition, mice immunized with the produced co-expressed α and e toxins proteins showed significantly higher surviving rate than with ε toxins protein alone when infected with culture filtrate of type D C. perfringens . These results indicated that co-expression of α and e toxins proteins could be used as a new method to prepare vaccines against the pathogens of multiple serotypes.

关键词： Clostridium perfingens α toxins ε toxins Co-expression

Correlation of effective hepatic blood flow with liver pathology in patients with hepatitis B virus

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Liver Research 2021年第4期5卷 243-250页

作者： Xin Shu Haixia Sun xiaoan Yang Yifan Jia Peiyan Xu Hong cao Ka Zhang Department of Infectious Diseases The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Department of Infectious Diseases Huadu District People's Hospital of GuangzhouGuangzhouChina

Background and aims:Effective hepatic blood flow(EHBF)decreases with liver disease progression,and identifying liver pathology is critical for patients with liver disease.This study was designed to elucidate the correlation between EHBF and liver pathology and explore the potential of EHBF for predicting the degree of liver pathology.Methods:In this study,207 patients with hepatitis B virus(HBV)who underwent liver biopsy and indocyanine green(ICG)clearance tests were enrolled.EHBF was measured using the ICG clearance test,and liver tissue was histologically analyzed to determine the pathological stage according to the Scheuer scoring system.Demographic data,biochemical indexes,and FibroScan data were collected for statistical analysis.Results:EHBF levels decreased as the liver histological stages of inflammation and fibrosis increased(P<0.01).EHBF was significantly negatively associated with the levels of alanine aminotransferase,aspartate aminotransferase,gamma-glutamyl transpeptidase,alkaline phosphatase,aspartate aminotransferase-to-platelet ratio index,fibrosis index based on the four factors,and liver stiffness measurement(P<0.05).The EHBF levels of patients without liver inflammation(G0)were significantly higher than those of patients with liver inflammation(G1e4)(P<0.001).The area under the receiver operating characteristic curve(AUROC)value for discriminating patients without liver inflammation was 0.827,and the optimal cutoff value was 0.936 L/min.The EHBF levels of patients with severe liver inflammation(G4)were significantly lower than those of patients with G0e3 liver inflammation(P<0.001).The AUROC value for discriminating patients with severe liver inflammation was 0.792,and the optimal cutoff value was 0.552 L/min.The EHBF levels of patients without liver fibrosis(S0)were significantly higher than those of patients with liver fibrosis(S1e4)(P<0.001).The AUROC value for discriminating patients without liver fibrosis was 0.633,and the optimal cutoff value was 1.173 L/min.The EHBF levels of patients w

关键词： Hepatitis B virus(HBV) Liver inflammation Liver fibrosis Effective hepatic blood flow(EHBF) Liver disease

Determination of laser entrance hole size for ignition-scale octahedral spherical hohlraums

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Matter and Radiation at Extremes 2022年第6期7卷 41-49页

作者： Yao-Hua Chen Zhichao Li Hui cao Kaiqiang Pan Sanwei Li Xufei Xie Bo Deng Qiangqiang Wang Zhurong cao Lifei Hou Xingsen Che Pin Yang Yingjie Li xiaoan He Tao Xu Yonggang Liu Yulong Li Xiangming Liu Haijun Zhang Wei Zhang Baibin Jiang Jun Xie Wei Zhou Xiaoxia Huang Wen Yi Huo Guoli Ren Kai Li Xudeng Hang Shu Li Chuanlei Zhai Jie Liu Shiyang Zou Yongkun Ding Ke Lan Institute of Applied Physics and Computational Mathematics Beijing 100094China Research Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900China Graduate School China Academy of Engineering PhysicsBeijingChina HEDPS Center for Applied Physics and Technologyand College of EngineeringPeking UniversityBeijing 100871China

A recently proposed octahedral spherical hohlraum with six laser entrance holes(LEHs)is an attractive concept for an upgraded laser facility aiming at a predictable and reproducible fusion gain with a simple target design.However,with the laser energies available at present,LEH size can be a critical issue.Owing to the uncertainties in simulation results,the LEH size should be determined on the basis of experimental evidence.However,determination of LEH size of an ignition target at a small-scale laser facility poses difficulties.In this paper,we propose to use the prepulse of an ignition pulse to determine the LEH size for ignition-scale hohlraums via LEH closure behavior,and we present convincing evidence from multiple diagnostics at the SGIII facility with ignition-scale hohlraum,laser prepulse,and laser beam size.The LEH closure observed in our experiment is in agreement with data from the National Ignition Facility.The total LEH area of the octahedral hohlraum is found to be very close to that of a cylindrical hohlraum,thus successfully demonstrating the feasibility of the octahedral hohlraum in terms of laser energy,which is crucially important for sizing an ignition-scale octahedrally configured laser system.This work provides a novel way to determine the LEH size of an ignition target at a small-scale laser facility,and it can be applied to other hohlraum configurations for the indirect drive approach.

关键词： laser size spherical

陶瓷基复合材料涡轮叶盘设计、制备与考核验证

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复合材料学报 2023年第3期40卷 1696-1706页

作者：刘小冲徐友良李坚罗潇郭小军胡晓安曹学强李龙彪刘持栋董宁刘永胜西北工业大学材料学院西安710072 中国航发湖南动力机械研究所株洲412000 南昌航空大学飞行器工程学院南昌330063 武汉理工大学材料科学与工程学院武汉430070 南京航空航天大学民航学院南京211106

涡轮转子是燃气涡轮发动机的核心部件。针对SiC/SiC涡轮叶盘设计、制备与考核验证开展研究,采用蛛网仿形(SWS)SiC纤维预制体作为涡轮叶盘的增强体,预制体表面分别沉积BN界面相与SiC基体,通“在线加工”方式对SiC/SiC涡轮叶盘分别进行粗... 详细信息

涡轮转子是燃气涡轮发动机的核心部件。针对SiC/SiC涡轮叶盘设计、制备与考核验证开展研究,采用蛛网仿形(SWS)SiC纤维预制体作为涡轮叶盘的增强体,预制体表面分别沉积BN界面相与SiC基体,通“在线加工”方式对SiC/SiC涡轮叶盘分别进行粗加工和精加工,采用大气等离子喷涂方法制备环境障碍涂层,形成满足设计要求的涡轮叶盘。采用CT对SiC/SiC涡轮叶盘进行无损检测,表征叶盘内部缺陷分布。针对制备的SiC/SiC涡轮叶盘开展性能评价、超转试验、台架试验等考核验证,研究表明:SiC/SiC涡轮叶盘最大破坏强度达到300 MPa;在室温超转试验中,当转速达到n=104 166 r/min时,叶片发生断裂,当转速达到n=108 072 r/min时,轮体发生破裂;在发动机台架试验中,累积完成了N=994次最高转速n^(max)=60 000 r/min的循环载荷及N=100次最高转速n_(max)=70 000 r/min的循环载荷试车考核。2022年1月1日,SiC/SiC涡轮叶盘在株洲成功完成了首次飞行试验验证,这也是国内陶瓷基复合材料转子首次配装平台的空中飞行试验,验证了SiC/SiC涡轮转子在航空发动机上应用的可行性。

关键词： SiC/SiC 涡轮叶盘蛛网仿形(SWS) 环境障碍涂层(EBCs) 超转试验台架试验燃气涡轮发动机

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我国人口城市化制度创新对策研究

当代经济研究 2006年第1期 29-32页

作者：曹晓军齐晓安东北师范大学经济与社会发展研究所吉林长春130021

人口城市化不仅要以工业化发展为前提,还和人口城市化进程的各项制度安排密切相关。我国原有的城乡分割的户籍制度、就业制度、社会保障制度及农村土地制度等已成为了阻碍人口城市化进程的障碍。要通过建立统一的户籍制度、健全农地流... 详细信息

人口城市化不仅要以工业化发展为前提,还和人口城市化进程的各项制度安排密切相关。我国原有的城乡分割的户籍制度、就业制度、社会保障制度及农村土地制度等已成为了阻碍人口城市化进程的障碍。要通过建立统一的户籍制度、健全农地流转机制、建立全国统一开放的劳动市场及完善社会保障制度等手段,实现人口城市化制度创新。

关键词：人口城市化制度创新户籍制度农地流转机制