检索结果-南通市图书馆

直接蒸发式CO_(2)人工冰场冰面温度影响因素

在线全文

学校读者我要写书评

暂无评论

制冷学报 2024年第4期45卷 114-123页

作者：吴静颜利波叶琳李敏霞马一太王派天津大学机械工程学院天津300072 广东美的暖通设备有限公司佛山528311 上海船舶设备研究所上海200031 天津商业大学机械工程学院天津市制冷技术重点实验室天津300134

以直接蒸发式室内CO_(2)人工冰场为研究对象,通过建立室内冰场稳定温度场数学模型,分析了当蒸发温度为-13℃,采用12.7 mm大管径铜管供冷时,室内人工冰场场地的质流密度、排管间距、含油率等因素对冰面温度和冰面温差的影响。结果表明:... 详细信息

以直接蒸发式室内CO_(2)人工冰场为研究对象,通过建立室内冰场稳定温度场数学模型,分析了当蒸发温度为-13℃,采用12.7 mm大管径铜管供冷时,室内人工冰场场地的质流密度、排管间距、含油率等因素对冰面温度和冰面温差的影响。结果表明:润滑油含量增加会增大管内压降及冰面进出口处的温差,但由于研究的管径和质流密度相对较大,影响幅度较小;供冷排管的间距和质流密度是影响冰面温度分布的主要因素;随着排管间距和质流密度的增大,冰面温差增大。为保证冰面温差在0.5℃以内,推荐的质流密度应小于200 kg/(m^(2)·s),排管间距应小于90 mm。

关键词： CO_(2) 直接蒸发人工冰场冰面温度

CO_(2)跨临界高温热泵干燥系统优化设计

在线全文

学校读者我要写书评

暂无评论

化学工程 2024年第9期52卷 26-31页

作者：颜利波王志朋张晧张宁曾海源李敏霞田华广东美的暖通有限公司广东佛山528308 天津大学机械工程学院天津300072

干燥工艺在工、农业生产中被广泛使用但耗能巨大,通过CO_(2)热泵干燥技术有望降低其能耗并减缓环境问题。文中在CO_(2)跨临界基本热泵干燥系统的基础上,提出CO_(2)跨临界复叠式热泵干燥系统和CO_(2)跨临界双级压缩并联加热热泵干燥系统... 详细信息

干燥工艺在工、农业生产中被广泛使用但耗能巨大,通过CO_(2)热泵干燥技术有望降低其能耗并减缓环境问题。文中在CO_(2)跨临界基本热泵干燥系统的基础上,提出CO_(2)跨临界复叠式热泵干燥系统和CO_(2)跨临界双级压缩并联加热热泵干燥系统。并且通过建立热力学模型将其最优性能系数C_(OPh)和单位能耗除湿率R_(SME)与R134a双循环热泵干燥系统进行了比较。研究发现,它们相较于CO_(2)基础系统性能均有提升,尤其是双级并联加热系统,其C_(OPh)与R_(SME)均超过R134a系统。进一步的分析显示,增加蒸发温度、降低气冷器出口温度对CO_(2)跨临界热泵干燥系统的性能提升起到了关键作用。此外,文中也探究了补气系数和干燥出风温度对CO_(2)跨临界热泵干燥系统的影响。研究结果表明:经过优化改进的CO_(2)跨临界热泵干燥在高效节能方面表现出色,展现了替代R134a热泵干燥系统的潜力,同时也为解决干燥工艺高能耗的问题提供了创新性和可行性的解决途径。

关键词： CO_(2)临界循环热力学分析最优性能热泵干燥

Leakage research on supercritical carbon dioxide fluid in rolling piston expander

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2012年第6期55卷 1711-1718页

作者： TIAN Hua MA YiTai li minxia liU ShengChun WANG KaiYang State Key Laboratory of Engine Tianjin UniversityTianjin 300072China Thermal Energy Research Institute Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Refrigeration Technology Tianjin University of CommerceTianjin 300134China

The leakage research on supercritical carbon dioxide fluid in rolling piston expander was investigated *** expander instead of throttle valve is an important way to improve the efficiency of carbon dioxide refrigeration ***,the supercritical fluid leakage in expander is serious and is the main factor affecting the expander's *** paper presented and compared four classic leakage *** analysis indicated that laminar leakage model is suitable in leakage simulation of expander.A leakage test system,including the leakage test part which has two types of leakage specimens with different gaps ranging from 5 to 15 m,was *** experimental results indicated that lubricant film played an important *** the leakage clearance of cylindrical specimen was 5 m,the mass flow rate of leakage was about 0.88 g *** data was 3.638 g s-1 with leakage clearance being 10 m and 7.11g s-1 with leakage clearance being 15 m.A modified leakage model was developed,whose average deviation was within 10% compared with the experimental *** last,this paper simulated the leakage in rolling piston expander presented by Tian et al.(2010).The leakage between rolling piston and cylinder was the most serious part with the value up to 0.04 kg s-1.

关键词： leakage supercritical carbon dioxide liquid rolling piston expander leakage model

Novel soybean peptide iglycin ameliorates insulin resistance of high-fat diet fed C57BL/6J mice and differentiated 3T3L1 adipocytes with improvement of insulin signaling and mitochondrial function

在线全文

学校读者我要写书评

暂无评论

Food Science and Human Wellness 2022年第6期11卷 1565-1572页

作者： Yinghuan Wu Ran Zhao minxia li Huiyun li Zhengwang Chen Yanying Zhao Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization of Ministry of Education Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization of Sichuan ProvinceCollege of Life Science and TechnologySouthwest Minzu UniversityChengdu 610041China Shandong Tianheng Inspection Co. Ltd.Heze 274000China Key Laboratory of Molecular Biophysics of Ministry of Education School of Life Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China

Soy consumption has been associated with potential health benefits in reducing chronic *** physiological functions have been attributed to soy proteins or more commonly to bioactive ***,more studies are required to identify these bioactive peptides,and elucidate their biological mechanisms of *** the present study,a novel peptide iglycin was purifi ed from soybean seeds with a molecular mass of 3.88 k ***,iglycin reduced fasting blood glucose and restored insulin sensitivity of C57 BL/6 J mice on a high-fat diet with increased phosphorylation of insulin receptor substrate 1(IRS1)and AKT in adipose ***,it improved glucose uptake,induced translocation of intracellular GLUT4 to plasma membrane and activation of insulin signaling in adipocytes under insulin-resistant *** addition,it decreased reactive oxygen species production,lipid peroxidation and inhibited adipocyte apoptosis with improved mitochondrial function as evidenced by up-regulation of succinate dehydrogenase activity,mitochondrial membrane potential and intracellular ATP *** data suggested that iglycin ameliorated insulin resistance via activation of insulin signaling,which was associated with inhibition of oxidative stress,adipocyte apoptosis,and improvement of mitochondrial function.

关键词： Soybean peptide Iglycin Insulin resistance Insulin signaling

Mb、cTnⅠ、CK-MB、BNP联合检测对早期急性心肌梗死的诊断价值

在线全文

学校读者我要写书评

暂无评论

系统医学 2024年第7期9卷 72-75页

作者：郦敏霞高卫亚袁晶晶丹阳市人民医院检验科江苏丹阳212300

目的探讨肌红蛋白(Myoglobin,Mb)、心肌肌钙蛋白Ⅰ(Cardiac Troponin,cTnⅠ)、肌酸激酶同工酶(Creatine Kinase Isoenzymes-MB,CK-MB)、脑利钠肽(Brain Natriuretic Peptide,BNP)联合检测对诊断早期急性心肌梗死的价值。方法选取2020年1月—2022年12月丹阳市人民医院收治的100例早期急性心肌梗死患者与100名健康体检者为研究对象,分别设为心梗组与健康组,均检测Mb、cTnⅠ、CK-MB、BNP水平,比较两组检测值的差异,另根据临床结果,评估联合检测对急性心肌梗死的诊断效能。结果心梗组Mb(92.84±22.52)ng/mL、cTnⅠ(4.96±0.78)ng/mL、CK-MB(48.91±14.62)U/L、BNP(1510.71±268.40)pg/mL,均高于健康组,差异有统计学意义(t=26.425、63.200、22.761、54.726,P均0.05)。结论早期急性梗死患者Mb、cTnⅠ、CK-MB、BNP水平明显异常,联合检测该4项指标可提高诊断效能。

关键词： Mb cTnⅠ CK-MB BNP 急性心肌梗死诊断效能

大量胎母输血综合征致新生儿重度贫血临床救治分析

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

中国妇幼健康研究 2024年第5期35卷 94-100页

作者：李敏霞郑海芸张亚南张巍首都医科大学附属北京妇产医院北京100026

目的分析大量胎母输血综合征(FMH)导致新生儿重度贫血的临床特点及诊治过程,以期提高对该疾病的认识及救治能力。方法回顾分析2012年1月至2021年12月首都医科大学附属北京妇产医院新生儿重症监护病房(NICU)收治的大量FMH导致新生儿重... 详细信息

目的分析大量胎母输血综合征(FMH)导致新生儿重度贫血的临床特点及诊治过程,以期提高对该疾病的认识及救治能力。方法回顾分析2012年1月至2021年12月首都医科大学附属北京妇产医院新生儿重症监护病房(NICU)收治的大量FMH导致新生儿重度贫血病例的母婴基本情况、疾病进程、治疗经过及结局。结果期间共39例孕妇确诊为大量FMH,发病率为0.28‰(39/140 727);最终有16例因大量FMH致新生儿重度贫血患儿纳入研究,足月儿8例,早产儿8例。在16例大量FMH孕妇的临床表现中,胎心监护均显示异常,8例有胎动减少表现;对16例孕妇进行的Kleihauer-Betke酸洗脱试验(KB试验)中,14例为阳性,2例为阴性(KB试验值分别为2.3%和1.2%)。在16例新生儿中,15例为急性剖宫产出生,1例自然分娩出生;新生儿出生后初始血红蛋白(Hb)为20~70g/L;15例出生后积极进行输血治疗,1例因家属放弃治疗未输血;其中4例合并新生儿颅内出血2级,2例合并重度新生儿血小板减少,1例合并失血性休克,1例合并胸腹腔积液和心力衰竭;有2例因家属考虑预后不良放弃治疗,其余14例均预后良好。结论大量FMH是导致新生儿重度贫血的病因之一,在临床中应加强对孕妇胎动的评估及宣教,孕晚期及时进行胎心监护,及早发现、尽早处理大量FMH,以及新生儿紧急输血是改善围产期儿预后的关键。

关键词：胎母输血综合征新生儿贫血输血机械通气

Research and application of CO_2 refrigeration and heat pump cycle

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2009年第6期52卷 1563-1575页

作者： TIAN Hua,YANG Zhao,li minxia & MA YiTai Thermal Energy Research Institute,Tianjin University,Tianjin 300072,China Thermal Energy Research Institute Tianjin University Tianjin China

The environmental problem caused by refrigerant has become the focus all over the *** the most typical natural refrigerant,CO2,of course,becomes the research *** paper introduces the development and application status of CO2 refrigeration and heat pump *** researches on CO2 refrigeration and heat pump,carried out by Thermal Energy Research Institute,Tianjin University,also are presented in this paper.

关键词： environmental problem natural refrigerant CO2 refrigeration heat pump

Molecular compositions and sources of organic aerosols at a rural site on the Guanzhong Plain,Northwest China:The importance of biomass burning

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第6期89卷 44-56页

作者： Yali liu minxia Shen Haijiao liu Wenting Dai Weining Qi Yifan Zhang Lu li Yue Cao Xin Wang Xiao Guo Yingkun Jiang Jianjun li State Key Laboratory of Loess and Quaternary Geology Key Lab of Aerosol Chemistry and PhysicsInstitute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China Xi'an Institute for Innovative Earth Environment Research Xi'an 710061China National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain ShaanxiChina

The concentration of PM_(2.5)has considerably reduced in recent years,but remains relatively high in *** particular,the increasing contribution of organic compounds to PM_(2.5)generates popular pressure for further reductions,resulting in an urgent need to study organic aerosol(OA).To investigate the molecular composition and source contribution of OA in the rural area of the Guanzhong Plain,Northwest China,PM_(2.5)samples were collected during 3–23 August 2016 and 5–20 January 2017 and studied for more than 100 organic tracer *** mean concentration of total measured organic compounds is 662±296 ng/m^(3)in summer and 3258±1925 ng/m^(3)in *** is the most abundant single compound found throughout the sampling period,which is a crucial tracer for biomass burning emissions,preliminary suggesting that biomass burning is an essential source of *** summer,organic compounds such as lipid compounds,sugar compounds,and polycyclic aromatic hydrocarbons(PAHs),more come from higher plants,wood burning,vehicle exhausts,plastic waste,and other direct emission *** PAHs(OPAHs),nitrophenols,and phthalic acids more come from the atmosphere through the oxidation reaction of aromatic precursors,especially photochemical ***,in winter,most of the increases in concentrations of organic compounds are attributed to biomass *** analysis of a haze event(14–19 January 2017)during the winter sampling period shows that the increases in the concentration of organic compounds are unaccompanied by strong secondary formation under lower relative humidity(49.1%±13.5%).The main reason for the growth of OA in this haze event is the accumulation of primary OA(POA).The source apportionment by the positive matrix factorization(PMF)model shows that biomass burning(37.1%)is the primary source of OA in the rural regions of the Guanzhong Plain,especially in winter(40.6%).The contribution of secondary formation decreases from 26.0%in summer t

关键词： Organic aerosol Molecular composition Seasonal variation Source apportionment Guanzhong Plain

Growth of nitrate contribution to aerosol pollution during wintertime in Xi'an,northwest China:Formation mechanism and effects of NH_(3)

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

Particuology 2024年第4期87卷 303-315页

作者： Hui Su Ting Zhang Suixin liu Yao Qu Huan li Jiamao Zhou Zhuzi Zhao Qiyuan Wang Lu li minxia Shen Shuoyuan Chen Steven Sai Hang Ho Junji Cao State Key Laboratory of Loess and Quaternary Geology.Key Laboratory ofAerosol Chemistry and Plhysics Institute of Earth EnvironmentChinese Acadery of SciencesXi'an 710061China Xi'an Institute for Innovative Earth Environment Research Xi'an 710061China National pbservation and Research Station of Regional Ecological Environment Change and Cornprehensive Management in the Guanzhong Plain Xi'an 710061China Shaanxi Key Laboratory of Atmospheric and Haze fog Pollution Prevention Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China University of Chinese Academy of Sciences Beijing 100049China School of Chemical and Environmental Engineering Jiangsu University of TechnologyChangzhou 213001China Division of Atmospheric Sciences Desert Research InstituteReno NV89512United States Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

With the strengthened controls on SO2 emissions and extensive increases in motor vehicles'exhaust,aerosol pollution shifts from sulfate-rich to nitrate-rich in recent years in Xi'an,*** further gain insights into the factors on nitrate formation and efficiently mitigate air pollution,highly time-resolved observations of water-soluble inorganic ions(WSIIs)in PM_(2.5) were measured in a suburban area of Xi'an,China during *** concentration of total WSIIs is 39.8μg m-3 on average,accounting for 50.3%of PM_(2.5) *** contrast to a slight decrease in the mass fraction of SO_(4)^(2-),NO_(3)-shows a sig-nificant increase of the PM_(2.5) contribution with the aggravation of aerosol *** suggests the importance of NO_(3)-formation to haze ***,homogeneous reactions govern the formation of NO_(3)-,while alkali metals such as calcium and sodium play an additional role in retaining NO_(3)-in PM_(2.5) during clean ***,the heterogeneous hydrolysis reaction contributed more to NO_(3)-formation during the pollution periods under high relative *** investigation reveals that temperature,relative humidity,oxidant,and ammonia emissions facilitate rapid NO_(3)-*** the random forest(RF)model,NO_(3)-concentrations were successfully simulated with measured variables for the training and testing datasets(R2>0.95).Among these variables,CO,NH_(3),and NO_(2) were found to be the main factors affecting the NO_(3)-*** with the period without vehicle re-striction,the contributions of NO_(3)-and NH4+to PM_(2.5) mass decreased by 5.3%and 3.4%in traffic re-striction periods,*** vehicle restriction leads to the decreases of precursor gases of NO_(2),SO_(2),and NH_(3) by 12.8%,5.9%,and 27.6%,*** results demonstrate collaborative emission reduction of NO_(x) and NH_(3) by vehicle restrictions,and using new energy vehicles(or electric vehicles)can effectively alleviate particul

关键词： PM_(2.5) Water-soluble inorganic ions Nitrate formation Excess ammonium Vehicle restrictions