检索结果-南通市图书馆

Experimental research on the heating performance of a single cylinder refrigerant injection rotary compressor heat pump with flash tank

引用

Science China(Technological Sciences) 2018年第12期61卷 1814-1823页

作者： SUN JinFei ZHU DongSheng YIN YingDe li xiuzhen Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Guangzhou 510640 China Key Laboratory of Renewable Energy Chinese Academy of Sciences Guangzhou 510640 China Guangdong Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640 China University of Chinese Academy of Sciences Beijing 100049 China

A single cylinder rotary compressor was applied in the refrigerant injection air-source heat pump to improve the heating performance in cold regions. In this study, the performance of an R410 A single cylinder rotary compressor vapor injection(SCRCVI) system was measured and analyzed by varying the compressor frequency f and injection pressure Pi njat the ambient temperature To d=–10°*** experimental results indicated that an optimum injection pressure to gain the maximum COP_h (coefficient of performance) existed in the SCRCVI cycle. However, the maximum COP_h of the SCRCVI system decreased as the increase of the frequency, and the maximum COPhwas even lower than that of the CSVC system at high compressor frequency. Therefore, in view of the energy saving and emission reduction, the SCRCVI system should be switched to single stage compression system when the heating capacity demand could be satisfied at high compressor frequency f. Compared to the conventional single-stage vapor compression(CSVC) system, refrigerant injection could enhance the heating capacities and COP_h by 28.2% and 7.91%, respectively. The average total mass flow rate of the SCRCVI system was 24.68% higher than that of the CSVC system. As the SCRCVI system worked at the optimum injection pressure, the variation trends of the different system parameters were investigated in detail. These trends were reliably used to optimize the refrigerant injection system design and the control strategy. The parameter of(P_(inj)–P_s) could be adopted as the signals to control the opening of the upper stage electronic expansion valve EEV1.

关键词： rotary compressor refrigerant injection DC (direct current) inverter heat pump heating performance injection pressure

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Distinct patterns of monthly Southern Annular Mode events

引用

Atmospheric and Oceanic Science Letters 2022年第4期15卷 38-43页

作者： Minglin Zheng xiuzhen li College of Meteorology and Oceanography National University of Defense TechnologyChangshaChina School of Atmospheric Sciences Sun Yat-sen UniversitySouthern Marine Science and Engineering Guangdong Laboratory(Zhuhai)China Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies Sun Yat-sen UniversityZhuhaiChina

The Southern Annular Mode(SAM)is the leading mode of atmospheric variability in the mid–high latitudes of the Southern Hemisphere,representing large-scale variations in pressure and the polar front jet(PFJ).In SAM events,the combination of the SAM and other modes may result in different atmospheric *** this study,a neural-network-based cluster technique,the self-organizing map,was applied to extract the distinct patterns of SAM events on the monthly time scale based on geopotential height anomalies at 500 *** pairs of distinguishable patterns of positive and negative SAM events were identified,representing the diversity in spatial distribution,especially the zonal symmetry of the center of action at high latitudes—that is,symmetric patterns,split-center patterns,West Antarctica patterns,and a tripole *** the SAM is well known to be beltshaped,within the selected SAM events,the occurrence frequency of symmetric patterns is only 23.8%—less than that of West Antarctica *** PFJ variations were found in the symmetric and asymmetric patterns of SAM *** more asymmetric the spatial distribution of the pressure anomaly,the more localized the adjusted zonal wind *** adjusted PFJ varied in meridional displacement and strength in different patterns of SAM *** addition,the entrance and exit of the jet changed in most of the patterns,especially in the asymmetric patterns,which might result in different climate impacts of the SAM.

关键词： Southern Annular Mode Self-organizing map Zonal asymmetry Antarctica

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Detecting the Origins of Moisture over Southeast China:Seasonal Variation and Heavy Rainfall

引用

Advances in Atmospheric Sciences 2016年第3期33卷 319-329页

作者： xiuzhen li Wen ZHOU Yongqin David CHEN Department of Geography and Resource Management The Chinese University of Hong Kong Guy Carpenter Asia–Pacific Climate Impact Centre School of Energy and EnvironmentCity University of Hong Kong Department of Geography and Resource Management and Institute of EnvironmentEnergy and SustainabilityThe Chinese University of Hong Kong

To examine the ability of the Hybrid Single-Particle Lagrangian Integrated Trajectory （HYSPliT） model to detect the origins and paths of moisture supplied to Southeast China, trajectories of air particles released over Southeast China were traced backward during 1 April 2012 to 31 March 2013 and three typical regional persistent heavy rainfall events. The HYSPliT model provides more insightful information than water vapor flux. Analysis of the specific humidity along the trajectories revealed the origins of moisture and their contributions to the moisture supply in Southeast China. In the boreal summer half year, four key moisture transport paths from the eastern Indian Ocean, central Indian Ocean, South China Sea （SCS）, and western North Pacific （WNP） contribute 10%, 20%, 31%, and 16% of the moisture to Southeast China, respectively. In the winter half year, the contributions of the paths from the WNP and North China double. Examination of heavy rainfall events showed that under tropical storm conditions, all moisture transport routines are rotated cyclonically before reaching Southeast China. The invasion of cold air can trigger heavy rainfall in both the summer and winter half years but plays different roles： it does not contribute to the moisture supply but plays a key role in converging and uplifting the moisture in the summer half year, while it supplies a great amount of moisture in the winter half year as it absorbs abundant moisture in crossing the WNE

关键词： moisture origin Southeast China HYSPliT seasonal variation heavy rainfall

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Deformation and Development Tendency of Shiliushubao Landslide by Numerical Modeling

引用

Wuhan University Journal of Natural Sciences 2006年第4期11卷 840-846页

作者： li xiuzhen KONG Jiming XU Qiang Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 Sichuan China School of Civil Engineering Southwest Jiaotong University Chengdu 610031 Sichuan China College of Environment and Civil Engineering Chengdu University of Technology Chengdu 610059 Sichuan China

On the basis of analysing basic features of Shiliushubao landslide, the landslide＇s deformation and development tendency are quantitatively studied by using FLA^3D program. The results accord with monitoring results. The results are indicated that resevoir impounding accelerates the landslide＇s deformation, and the variation of reservoir water level is key factor of affecting the deformation; The landslide has the characters of pull-behind move ment according to the displacement of the landslide body gradually reducing from leading edge to trailing edge; Excavating and deloading slow down the landslide＇s deformation in the certain degree. On the basis, the deformation developmental tendency of Shiliushubao landslide is predicted by the established simulating model.

关键词： Shiliushubao landslide deformation rule develop ment tendency numerical modeling

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Thermal-Hydraulic Characteristics of Twisted Elliptical Tube Bundle in Staggered Arrangement

引用

Journal of Thermal Science 2021年第6期30卷 1925-1937页

作者： li xiuzhen WANG lin FENG Rong WANG Zhanwei ZHU Dongsheng Institute of Building Energy and Thermal Science Henan University of Science and TechnologyLuoyang 471023China CAS Key Laboratory of Renewable Energy Guangzhou 510640China School of Mechanical Engineering Shaanxi Key Laboratory of Industrial AutomationShaanxi University of TechnologyHanzhong 723001China

Based on experimental data,numerical simulations by turbulent air flowing across staggered tube bundle composed of twisted elliptical tube(TET)with constant tube wall temperature are conducted in present *** study on the thermal-hydraulic characteristics of air crossflow in TET bundles is investigated with physical parameters and Reynolds number(Re).The results show that spiral channels created by spiral deformation of TETs have a diversion effect on the air flow,which changes the flow direction of the air near the tube *** air in the near wall region is a three-dimensional flow,consisting of a flow perpendicular to the normal direction of the elliptical cross section and a spiral flow along the helicoid on the downstream side and the upstream *** the interaction of the spiral channels makes the two flows and their mixing more *** excellent heat transfer performance of staggered TET bundles is confirmed by the comparison of the comprehensive heat transfer performance with that of circular tube *** average Nusselt number(Nu)increases with the increase of the aspect ratio(A/B)and with the increase of Re while decreases as the twist pitch(S)*** average Euler number(Eu)increases as A/B increases,while it decreases as Re increases and as S *** to the fact that the suitable correlations for staggered TET bundles are not reported,correlations for Nu and Eu obtained from experimental data and numerical results are presented in the multiple forms.

关键词： twisted elliptical tube heat transfer enhancement pressure drop performance cross flow

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The Discovery of Natural Native Uranium and Its Significance

引用

Acta Geologica Sinica(English Edition) 2015年第5期89卷 1561-1567页

作者： li Ziying HUANG Zhizhang li xiuzhen GUO Jian FAN Chou Beijing Research Institute of Uranium Geology South-Central University for Nationalities

This study analyzed the composition and uranium valence of pitchblendes sampled from the hydrothermal Guidong and Zhuguang uranium deposits of the middle Nanling metallogenic belt, Southern China using X-ray photoelectron spectroscopy（XPS）.A revolutionary discovery is that the uranium not only exists in the forms of tetravalent and hexavalent uranium oxides, but also occurs in the form of native *** is the first discovery of the existence of native uranium in *** greatly helps to reveal the origin of hydrothermal mineralization of uranium, and also has great significance for studying the thermal energy, formation and evolution of the earth.

关键词： pitchblende uranium deposit native uranium first discovery metallogenic origin

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Energy and Exergy Analysis of a Cooling/Power Cogeneration Ejector Refrigeration System

引用

Journal of Thermal Science 2022年第2期31卷 448-462页

作者： YANG Mengke li xiuzhen WANG lin YUAN Junfei WANG Zhanwei liANG Kunfeng Institute of Refrigeration and Air conditioning Henan University of Science and TechnologyLuoyang 471023China

The organic Rankine cycle is introduced into the conventional ejector refrigeration(CER)system to establish the low-grade heat-driven cooling/power cogeneration ejector refrigeration(CPC-ER)system using the isobutane as the *** comparison with the CER system where external power is consumed by the circulating pump,the power output from the CPC-ER system is more than the power consumption of its circulating pump so that a portion of net power is derived from the CPC-ER *** on the mathematical model of thermodynamics,energy and exergy analysis of the CPC-ER system is carried out and compared with the CER *** results reveal that the equivalent coefficient of performance(COP)of the CPC-ER system is 41.14%to 71.30%higher than that of the CER system,and the exergy efficiency of the CPC-ER system is 1.32 to 1.49 times higher than that of the CER *** the power produced by the turbine and the total exergy output from the CPC-ER system approach the maximum,as the generating temperature in the generator is up to 80°*** CPC-ER system has the higher energy utilization efficiency than the CER system,and it is suitable for the cooling and power-required places with low-grade thermal sources.

关键词： ejector refrigeration exergy power consumption equivalent COP

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of temperature and moisture on soil organic carbon mineralization of predominantly permafrost peatland in the Great Hing'an Mountains,Northeastern China

引用

Journal of Environmental Sciences 2010年第7期22卷 1057-1066页

作者： Xianwei Wang xiuzhen li Yuanman Hu Jiujun Lv Ju Sun Zongmei li Zhifeng Wu Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China Graduate School of Chinese Academy of Sciences Beijing 100039 China Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China

Boreal peatlands represent a large global carbon pool. The relationships between carbon mineralization, soil temperature and moisture in the permafrost peatlands of the Great Hing＇an Mountains, China, were examined. The CO2 emissions were measured during laboratory incubations of samples from four sites under different temperatures （5, 10, 15, and 20℃） and moisture contents （0%, 30%, 60%, 100% water holding capacity （WHC） and completely water saturated）. Total carbon mineralization ranged from 15.51 to 112.92 mg C under the treatments for all sites. Carbon mineralization rates decreased with soil depth, increased with temperature, and reached the highest at 60% WHC at the same temperature. The calculated temperature coefficient （Q10） values ranged from 1.84 to 2.51 with the soil depths and moisture. However, the values were not significantly affected by soil moisture and depth for all sites due to the different peat properties （P 〉 0.05）. We found that the carbon mineralization could be successfully predicted as a two-compartment function with temperature and moisture （R^2 〉 0.96） and total carbon mineralization was significantly affected by temperature and moisture （P 〈 0.05）. Thus, temperature and moisture would play important roles in carbon mineralization of permafrost peatlands in the Great Hing＇an Mountains, indicating that the permafrost peatlands would be sensitive to the environment change, and the permafrost peatlands would be potentially mineralized under future climate change.

关键词： Great Hing'an Mountains permafrost peatland mineralization climate change

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Occurrence and transfer of heavy metals in sediments and plants of Aegiceras corniculatum community in the Qinzhou Bay,southwestern China

引用

Acta Oceanologica Sinica 2020年第2期39卷 79-88页

作者： Xing Huang Xueping Wang xiuzhen li Zhongzheng Yan Yongguang Sun Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf Beibu Gulf UniversityQinzhou 535011China State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200062China National Marine Environment Monitoring Center Dalian 116023China

Mangrove wetlands can reduce heavy metal pollution by trapping heavy *** this study,the concentration,transport and bioaccumulation of Cr,Cd,Cu,Zn and Pb in the sediments and different parts of Aegiceras corniculatum at four different sites in the Qinzhou Bay in southwestern China were *** results showed that although the potential ecological risk of all five heavy metals was slight,the concentration of Cr was at a moderate pollution level due to the emissions of industries and aquaculture waste *** sediment records indicated that the concentrations of heavy metals at the depth of 0–20 cm were relatively high,showing an increasing trend of heavy metals over the past 20–30 ***,Cu,Pb and Cd accumulated mainly in the roots of ***,while Zn accumulated mainly in the *** corniculatum showed the strongest transport capacity for Zn and Cu and the strongest bioaccumulation ability for *** with other mangrove communities,*** can be chosen as a restoration species in tropical and subtropical coastal zones polluted by Zn,Cu and Cd.

关键词： Aegiceras corniculatum sediment heavy metals accumulation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

TRIM14 promotes endothelial activation via activating NF-κB signaling pathway

引用

Journal of Molecular Cell Biology 2020年第3期12卷 176-189页

作者： Xuan Huang Yong li xiuzhen li Daping Fan Hong-Bo Xin Mingui Fu Institute of Translational Medicine Nanchang UniversityNanchang 330031China Department of Biomedical Science and Shock/Trauma Research Center School of MedicineUniversity of Missouri-Kansas CityKansas CityMO 64108USA Department of Cell Biology and Anatomy University of South Carolina School of MedicineColumbiaSC 29209USA

Endothelial activation by proinflammatory cytokines is closely associated to the pathogenesis of atherosclerosis and other vascular diseases;however, the molecular mechanisms controlling endothelial activation are not fully understood. Here we identify TRIM14 as a new positive regulator of endothelial activation via activating NF-κB signal pathway. TRIM14 is highly expressed in human vascular endothelial cells (ECs) and markedly induced by inflammatory stimuli such as TNF-α, IL-1β, and LPS. Overexpression of TRIM14 significantly increased the expression of adhesion molecules such as VCAM-1, ICAM-1, E-selectin, and cytokines such as CCL2, IL-8, CXCL-1, and TNF-α in activated ECs and by which it facilitated monocyte adhesion to ECs. Conversely, knockdown of TRIM14 has opposite effect on endothelial activation. Upon TNF-α stimulation, TRIM14 is recruited to IKK complex via directly binding to NEMO and promotes the phosphorylation of IκBα and p65, which is dependent on its K63-linked ubiquitination. Meanwhile, p65 can directly bind to the promoter regions of human TRIM14 gene and control its mRNA transcription. Finally, TRIM14 protein level is significantly upregulated in mouse and human atheroma compared to normal arteries. Taken together, these results indicate that TRIM14-NF-κB forms a positive feedback loop to enhance EC activation and TRIM14 may be a potential therapeutic target for vascular inflammatory diseases such as atherosclerosis.

关键词： TRIM14 NF-κB endothelial activation atherosclerosis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：