检索结果-南通市图书馆

Design and preliminary experimental investigation of a 4K Stirling-type pulse tube cryocooler with precooling

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第9期10卷 1277-1284页

作者： Zhi-hua GAN zhuo-pei LI Jie CHEN Li DAI Li-min QIU Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

A Stirling-type pulse tube cryocooler （PTC） with precooling was designed and manufactured to investigate its performance at 4 K. Numerical simulation was carried out based on the well-known regenerator model REGEN with an emphasis on the performance of a 4 K stage regenerator of the Stifling-type PTC as influenced by the warm end temperature, pressure ratio, frequency and average pressure with helium-4 and helium-3 as the working fluid respectively. This study demonstrates that the use of a cold inertance tube can significantly improve the efficiency of a 4 K Stirling-type PTC. A preliminary experimental investigation was carried out with helium-4 as the working fluid and a refrigeration temperature of 4.23 K was achieved. The experimental results show that the operating frequency has a significant influence on the performance of the Stirling-type PTC and a relatively low average pressure is favorable for decreasing the loss associated with the real gas effects of a 4 K Stirling-type PTC.

关键词： Stirling-type pulse tube cryocooler (PTC) Regenerator Helium-3 Cold inertance tube 4 K

危险性上消化道出血急诊快速救治通道效果的回顾分析

在线全文

学校读者我要写书评

暂无评论

岭南急诊医学杂志 2024年第1期29卷 4-7页

作者：李鸿威吴壮填卓培炫王鹏飞中山大学孙逸仙纪念医院深汕中心医院急诊科 516600 中山大学孙逸仙纪念医院急诊科

目的:探讨危险性上消化道出血急救快速通道是否对此类疾病患者诊治产生积极影响。方法:回顾性病例分析2021年12月-2022年12月在我院就诊的危险性上消化道出血患者共66例,以我院成立危险性上消化道出血急诊快速救治通道的时间为界分为传... 详细信息

目的:探讨危险性上消化道出血急救快速通道是否对此类疾病患者诊治产生积极影响。方法:回顾性病例分析2021年12月-2022年12月在我院就诊的危险性上消化道出血患者共66例,以我院成立危险性上消化道出血急诊快速救治通道的时间为界分为传统组和通道组,采集患者详细资料进行分析,比较其24小时内胃镜完成率;入院至胃镜完成时间;入院至止血时间;急诊停留时长;入院天数;入院总费用等关键指标及预后相关指标。结果:通道组患者24小时内胃镜完成率显著高于传统组(P<0.05),完成胃镜时间、急诊停留时长、入院至止血时间以及费用超过中位数比例显著低于传统组(P<0.05)。结论:危险性上消化道出血急救快速通道能显著提高诊疗效率并节省诊疗费用。

关键词：危险性上消化道出血急诊快速救治通道多学科诊疗团队急诊胃镜

Circ-Smad5 retards the G1/S transition of cell cycle via inhibiting the activity of wnt/lef/cyclind1 signaling in JB6 cells

在线全文

学校读者我要写书评

暂无评论

Genes & Diseases 2021年第3期8卷 364-372页

作者： Xiaogen Ma Fei Xiang zhuo pei Jiafeng Miao Pan Wu Xiaofeng Song Yuhong Li Yiming Zhang Department of Plastic and Cosmetic Surgery Xinqiao HospitalArmy Medical UniversityChongqing400037PR China Department of Cell Biology Army Medical UniversityChongqing400038PR China Institute of Burn Research State Key Laboratory of TraumaBurns and Combined InjurySouthwest HospitalArmy Medical UniversityChongqing400038PR China Department of Biomedical Engineering Nanjing University of Aeronautics and AstronauticsNanjing211106PR China

Circular RNAs are a large class of noncoding ***5 functions in cell differentiation,cell proliferation and *** has been reported that lnc-Smad5 can inhibit the proliferation of diffuse large B cell ***,the function of circ-Smad5 has not yet been *** vectors were constructed to establish circ-Smad5 upregulated and circ-Smad5 downregulated cell models.A CCK-8 assay was used to detect the proliferation of JB6 *** was used to analyze the cell cycle in the cell *** blot,immunofluorescence staining and TOP/FOP flash dual luciferase activity assays were used to determine the activity of the Wnt signaling *** results revealed that the expression level of circ-Smad5 in JB6 cells was significantly lower than the expression level of *** with the control group,the percentage of S phase cells and the expression level of cyclin D1 protein were significantly higher in the sh-circ-Smad5 *** the sh-circSmad5 group,b-catenin and LEF-1 were significantly increased,p-b-catenin was significantly decreased,and the relative activity of the TOP/FOP reporter gene was higher compared to the control group *** phenomena could be reversed by treating with Wnt signaling inhibitor *** conclude that the circ-Smad5 retards the proliferation and the cell cycle progression of JB6 ***,circ-Smad5 may function by inhibiting the activation of Wnt/b-catenin/Lef 1 signaling,which inhibits the expression of cyclin *** the best of our knowledge,we are the first to report the function of circ-Smad5.

关键词： Cell cycle Circ-Smad5 Circular RNA Wnt signaling Cell proliferation

Modularized and Parametric Modeling Technology for Finite Element Simulations of Underground Engineering under Complicated Geological Conditions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第7期140卷 621-645页

作者： Jiaqi Wu Li zhuo Jianliang pei Yao Li Hongqiang Xie Jiaming Wu Huaizhong Liu State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China Research Institute of Testing and Inspection Sinohydro Bureau 7 Co.Ltd.Chengdu610213China

The surrounding geological conditions and supporting structures of underground engineering are often updated during construction,and these updates require repeated numerical *** improve the numerical modeling efficiency of underground engineering,a modularized and parametric modeling cloud server is developed by using Python *** basic framework of the cloud server is as follows:input the modeling parameters into the web platform,implement Rhino software and FLAC3D software to model and run simulations in the cloud server,and return the simulation results to the web *** modeling program can automatically generate instructions that can run the modeling process in Rhino based on the input modeling *** main modules of the modeling program include modeling the 3D geological structures,the underground engineering structures,and the supporting structures as well as meshing the geometric *** particular,various cross-sections of underground caverns are crafted as parametricmodules in themodeling *** and parametric modeling program is used for a finite element simulation of the underground powerhouse of the Shuangjiangkou Hydropower *** complicatedmodel is rapidly generated for the simulation,and the simulation results are ***,this modularized and parametric modeling program is applicable for three-dimensional finite element simulations and analyses.

关键词： Underground engineering modularized and parametric modeling finite element method complex geological structure cloud modeling

采用Gd_2O_2S回热填料的带预冷4K斯特林型高频脉管制冷机性能研究（英文）

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2014年第7期15卷 508-516页

作者： zhuo-pei LI Yan-long JIANG Zhi-hua GAN Li-min QIU Jie CHEN Man-machine Environment Engineering College of Aerospace EngineeringNanjing University of Aeronautics and Astronautics Institute of Refrigeration and Cryogenics Zhejiang University Nanjing Cooltech Cryogenic Technology Co. Ltd.

研究目的:研究新型磁性回热填料Gd2O2S对液氦温区高频脉管制冷机多级回热器损失特性的影响。创新要点:确定了不同回热填料以及运行参数(频率、平均压力)下液氦温区多级脉管制冷机的制冷温度和各级预冷量,进一步明确了4 K高频回热损失机... 详细信息

研究目的:研究新型磁性回热填料Gd2O2S对液氦温区高频脉管制冷机多级回热器损失特性的影响。创新要点:确定了不同回热填料以及运行参数(频率、平均压力)下液氦温区多级脉管制冷机的制冷温度和各级预冷量,进一步明确了4 K高频回热损失机理。研究方法:采用理论研究与实验验证相结合的方法,基于一台两级G-M型低频脉管制冷机预冷的单极斯特林型高频脉管制冷机,研究多级回热器在高频以及4 K温区下的损失特性。选取新型回热填料Gd2O2S替代部分回热填料HoCu2,比较回热器采用两种填料时在不同运行频率及平均压力下的冷端制冷温度(图10)、各级预冷量和预冷温度(图11–12)。重要结论:采用孔隙率较小的新型磁性回热填料Gd2O2S可显著改善第一级回热器内压力波与质量流的相位关系,从而减小该级回热损失。减小平均压力可以降低制冷机无负荷制冷温度并减小第二级预冷量,但制冷工质氦的体积比热容会急剧增大,从而使低温级回热器的换热对频率非常敏感。此外,频率对高温级回热器的回热特性影响不明显。该方法可以为三级斯特林型4 K多级脉管制冷机提供设计依据。

关键词：斯特林型脉管制冷机回热填料 4K 高频预冷低温惯性管

Telomere-to-telomere carrot (Daucus carota) genome assembly reveals carotenoid characteristics

在线全文

学校读者我要写书评

暂无评论

Horticulture Research 2023年第7期10卷 112-124页

作者： Ya-Hui Wang pei-zhuo Liu Hui Liu Rong-Rong Zhang Yi Liang Zhi-Sheng Xu Xiao-Jie Li Qing Luo Guo-Fei Tan Guang-Long Wang Ai-Sheng Xiong State Key Laboratory of Crop Genetics&Germplasm Enhancement and Utilization Ministry of Agriculture and Rural Affairs Key Laboratory of Biology and Germplasm Enhancement of Horticultural Crops in East ChinaCollege of HorticultureNanjing Agricultural UniversityNanjingJiangsu 210095China Institute of Horticulture Guizhou Academy of Agricultural SciencesGuiyangGuizhou 550025China School of Life Science and Food Engineering Huaiyin Institute of TechnologyHuaianJiangsu 223003China Beijing Vegetable Research Center Beijing Academy of Agriculture and Forestry SciencesKey Laboratory of Biology and Genetic Improvement of Horticultural Crops in North ChinaBeijing 100097China

Carrot(Daucus carota)is an Apiaceae plant with multi-colored fleshy roots that provides a model system for carotenoid *** this study,we assembled a 430.40 Mb high-quality gapless genome to the telomere-to-telomere(T2T)level of“Kurodagosun”*** total,36268 genes were identified and 34961 of them were functionally *** proportion of repeat sequences in the genome was 55.3%,mainly long terminal *** on the coverage of the repeats,14 telomeres and 9 centromeric regions on the chromosomes were predicted.A phylogenetic analysis showed that carrots evolved early in the family *** on the T2T genome,we reconstructed the carotenoid metabolic pathway and identified the structural genes that regulate carotenoid *** the 65 genes that were screened,9 were newly ***,some gene sequences overlapped with transposons,suggesting replication and functional differentiation of carotenoid-related genes during carrot *** that some gene copies were barely expressed during development,they might be functionally *** of 24 cytochrome P450 genes associated with carotenoid biosynthesis revealed the tandem or proximal duplication resulting in expansion of CYP gene *** results provided molecular information for carrot carotenoid accumulation and contributed to a new genetic resource.

关键词： carrot sequences characteristics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

总供给-总需求模型的解释

数量经济技术经济研究 2000年第6期17卷 56-57页

作者：左大培中国社会科学院经济研究所

根据对我国的宏观总需求和总供给行为的理论分析,可以得出我国的总需求函数和总供给函数。利用统计数据对这些函数进行检验,可以回归出说明我国总需求和总供给的行为的经验方程。这里依据这些回归方程来解释最近几年我国的经济增长率和... 详细信息

根据对我国的宏观总需求和总供给行为的理论分析,可以得出我国的总需求函数和总供给函数。利用统计数据对这些函数进行检验,可以回归出说明我国总需求和总供给的行为的经验方程。这里依据这些回归方程来解释最近几年我国的经济增长率和物价总水平变动率。我们回归出的经验方程有4个,其中有两个是说明总需求如何决定“总需求函数”的:

关键词：总供给模型总需求模型解释总需求函数

Insulin Autoimmune Syndrome： 73 Cases of Clinical Analysis

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2015年第17期128卷 2408-2409页

作者： Yun-Lin Wang pei-Wei Yao Xiao-Ting Zhang zhuo-Zhang Luo pei-Qiang Wu Fang Xiao Department of Internal Medicine Second People's Hospital of Foshan Foshan Guangdong 528000 China

Autoimmune hypoglycemia, also called insulin autoimmune syndrome （IAS）, was first reported by Hirata and Ishizu in 1972 in Japan. IAS is characterized by the diagnostic criteria of spontaneous hypoglycemia without evidence of exogenous insulin administration, high levels of total immunoreactive insulin, and the presence of a high titer of insulin autoantibodies.

关键词： Clinical Features Insulin Autoimmune Syndrome Treatments

On-chip integrated GeSe_(2)/Si vdW heterojunction for ultravioletenhanced broadband photodetection,imaging,and secure optical communication

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第7期17卷 6544-6549页

作者： Zhiman Zhou Kunxuan Liu Di Wu Yunrui Jiang Ranran zhuo pei Lin Zhifeng Shi Yongtao Tian Wei Han Longhui Zeng Xinjian Li School of Physics and Microelectronics Key Laboratory of Material Physics Ministry of EducationZhengzhou UniversityZhengzhou 450052China Department of Electrical and Computer Engineering University of California San DiegoLa JollaCalifornia 92093USA Institute of Microelectronics and Integrated Circuits School of MicroelectronicsHubei UniversityWuhan 430062China

Broadband photodetection,spanning from ultraviolet(UV)to infrared(IR),is pivotal in diverse technological domains including astronomy,remote sensing,environmental monitoring,and medical ***,current commercially available broadband photodetectors,predominately based on conventional narrow-bandgap semiconductors,exhibit limited sensitivity in the UV *** limitation,stemming from the significant energy disparity between the semiconductor bandgap and UV photon,narrows their application ***,we report an innovative approach involving the in-situ van der Waals(vdW)integration of two-dimensional(2D)GeSe_(2)layers onto a Si *** process yields a high-quality GeSe_(2)/Si vdW heterojunction device,which features a broad response range covering from UV to near-IR(NIR)with a greatly-enhanced sensitivity in the UV *** device possesses high responsivities of 325 and 533.4 mA/W,large detectivities of 1.24×10^(13)and 2.57×10^(13)Jones,and fast response speeds of 20.6/82.1 and 17.7/81.0μs under 360 and 980 nm,***,the broadband image sensing and secure invisible optical communication capabilities of the GeSe_(2)/Si heterojunction device are *** work provides a viable approach for UV-enhanced broadband photodetection technology,opening up new possibilities and applications across various scientific and technological domains.

关键词： germanium diselenide van der Waals(vdW)integration ultraviolet enhanced broadband photodetection imaging