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大型冷库冷间的隔热保温吊顶一体化施工 被引量:1
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作者 甘宗华 《建筑施工》 2019年第4期611-614,共4页
针对常规设计的冷库冷间在底层及顶层设计架空层而造成的冷库内部空间浪费,提出了采用隔热保温吊顶一体化施工技术,不仅可以取消顶部架空层,提升了冷库的冷藏容积,而且降低了顶部保温系统造价,解决了冷库传统设计顶部保温及空间利用问题。
关键词 冷库 冷间 隔热保温 热阻
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钛合金内六角螺钉冷间锻造量产技术在日本问世
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《中国科技信息》 2004年第18期16-16,共1页
关键词 钛合金 六角螺钉 冷间锻造量产技术 日本 切削加工 用途
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冷库冷间隔热保温吊顶一体化施工技术
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作者 冯山青 《中文科技期刊数据库(全文版)工程技术》 2021年第6期187-188,共2页
随着食品行业发展速度的加快我国冷库建设的规模在逐渐的扩大在对冷库冷间设计的过程中,必须从冷库周边环境以及使用的实际情况出发,不断做好冷库冷间的隔热保温工作。冷库冷间建设的过程中施工人员做好地面冷涨破坏以及顶部保温的施工... 随着食品行业发展速度的加快我国冷库建设的规模在逐渐的扩大在对冷库冷间设计的过程中,必须从冷库周边环境以及使用的实际情况出发,不断做好冷库冷间的隔热保温工作。冷库冷间建设的过程中施工人员做好地面冷涨破坏以及顶部保温的施工,确保冷库冷间能够满足使用的需要。保温吊顶一体化施工技术能够有效提高冷酷冷间的实际使用效果,为施工单位节约一定的建设成本,并有效扩大了冷库冷间的实际冷藏容积。 展开更多
关键词 冷库冷间 隔热保温 吊顶一体化 施工技术
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Effect of thermo-mechanical treatment on microstructure and mechanical properties of wire-arc additively manufactured Al-Cu alloy
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作者 ZHANG Tao QIN Zhen-yang +2 位作者 GONG Hai WU Yun-xin CHEN Xin 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2181-2193,共13页
Wire-arc additive manufacture(WAAM)has great potential for manufacturing of Al-Cu components.However,inferior mechanical properties of WAAM deposited material restrict its industrial application.Inter-layer cold rolli... Wire-arc additive manufacture(WAAM)has great potential for manufacturing of Al-Cu components.However,inferior mechanical properties of WAAM deposited material restrict its industrial application.Inter-layer cold rolling and thermo-mechanical heat treatment(T8)with pre-stretching deformation between solution and aging treatment were adopted in this study.Their effects on hardness,mechanical properties and microstructure were analyzed and compared to the conventional heat treatment(T6).The results show that cold rolling increases the hardness and strengths,which further increase with T8 treatment.The ultimate tensile strength(UTS)of 513 MPa and yield stress(YS)of 413 MPa can be obtained in the inter-layer cold-rolled sample with T8 treatment,which is much higher than that in the as-deposited samples.The cold-rolled samples show higher elongation than that of as-deposited ones due to significant elimination of porosity in cold rolling;while both the T6 and T8 treatments decrease the elongation.The cold rolling and pre-stretching deformation both contribute to the formation of dense and dispersive precipitatedθ′phases,which inhibits the dislocation movement and enhances the strengths;as a result,T8 treatment shows better strengthening effect than the T6 treatment.The strengthening mechanism was analyzed and it was mainly related to work hardening and precipitation strengthening. 展开更多
关键词 wire-arc additive manufacture inter-layer cold rolling thermal-mechanical treatment microstructure mechanical properties strengthening mechanism
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OPTIMUM OF PRESSURE RATIOS OF MULTI-STAGE RECIPROCATING COMPRESSOR WITH PRACTICAL INTER-COOLING 被引量:1
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作者 刘卫华 昂海松 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期177-181,共5页
The optimum pressure ratio distribution of a multistage reciprocating compressor is presented based on the assumption, i.e. the inter stage cooling is perfect and there are no pressure losses. The optimization of the... The optimum pressure ratio distribution of a multistage reciprocating compressor is presented based on the assumption, i.e. the inter stage cooling is perfect and there are no pressure losses. The optimization of the two or three stage pressure ratio is analyzed in two cases of constant heat transfer rate for the inter cooler or constant inter stage inlet temperature, based on the minimum of the sum of theoretical compression power at each stage about a multi stage reciprocating compressor. Furthermore, with an example of two stage compressor the influence on the sum of the power of each stage is analyzed when practical pressure ratio deviates from the optimum value. It is obtained that under different cooling conditions the optimum pressure ratio distribution of the multi stage compression is various, and the change of the optimum pressure ratio within a small range has little influence on the sum of the power each stage. For the two stage compression, this range can be represented as ε 1=(0 96~1 06)ε 1j . 展开更多
关键词 inter cooler multi stage compressor pressure ratio OPTIMUM
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冷库建筑设计中的问题探讨 被引量:1
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作者 文茜茜 《中国科技期刊数据库 工业A》 2022年第12期110-112,共3页
冷库建筑这门学科,是冷藏科学技术领域里的一个重要组成部分。直到19世纪中期,人工制冷技术取得了成功,在压缩式和吸收式冰箱出现后,食品的冷冻储存得到了极大的发展。国外冷库行业发展迅速的国家主要有日本、美国、芬兰、加拿大等国家... 冷库建筑这门学科,是冷藏科学技术领域里的一个重要组成部分。直到19世纪中期,人工制冷技术取得了成功,在压缩式和吸收式冰箱出现后,食品的冷冻储存得到了极大的发展。国外冷库行业发展迅速的国家主要有日本、美国、芬兰、加拿大等国家。国内制冷设备专业生产和冷库建设也在快速发展,从高温冷库、低温冷库、冷冻冷库到综合冷库,从普通冷库到一系列品种规格各异的气调库。然而,在冷库的发展中存在着许多问题。简要讨论了冷库建筑设计中存在的问题。 展开更多
关键词 冷库 冷间 保温 预应力结构 消防设计
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Design calculation of porous ceramics tube type dew point indirect evaporative cooler 被引量:1
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作者 毛秀明 黄翔 文力 《Journal of Southeast University(English Edition)》 EI CAS 2010年第2期205-208,共4页
To improve the wall surface hydrophilicity of a tube type indirect evaporative cooler,a new method adopting porous ceramics is proposed.This method realizes the combination of porous ceramics and the evaporative cooli... To improve the wall surface hydrophilicity of a tube type indirect evaporative cooler,a new method adopting porous ceramics is proposed.This method realizes the combination of porous ceramics and the evaporative cooling technique.The design calculation of the porous ceramics tube type dew point indirect evaporative cooler are carried out from such aspects as the volumes and status parameters of the primary and secondary air,the cooler structure,the heat transfer of the solid porous ceramic tubes and the resistance of the cooler.The calculation results show that the design is reasonable.Finally,based on the design calculation,the porous ceramics tube type dew point indirect evaporative cooler is successfully manufactured. 展开更多
关键词 tube type indirect evaporative cooler dew point porous ceramics design calculation
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《欢乐总动员》节目主持人访谈
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《上海戏剧》 1999年第1期24-25,共2页
张:现在这台《欢乐总动员》比较我以前主持的节目要更专业,更全面,不管从灯光、摄影、布景等方面,更重要的是它有一种节奏感,当主持人、嘉宾和现场观众都具有了同一节奏的时候。
关键词 节目主持人 观众 现场观 持节 事情 中央台 色对比 冷间 本意 港台片
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OPTIMAL PERFORMANCE OF THERMOELECTRIC REFRIGERATION SYSTEM USING ENTROPY GENERATION MINIMIZATION METHOD 被引量:2
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作者 曹业玲 夏文庆 余莉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第4期339-343,共5页
With the entropy generation minimization (EGM) method, the thermodynamical performance optimization in a thermoelectric refrigeration system is studied. The optimization is affected by the irreversibility of heat tr... With the entropy generation minimization (EGM) method, the thermodynamical performance optimization in a thermoelectric refrigeration system is studied. The optimization is affected by the irreversibility of heat transfer caused by finite temperature differences, the heat leak between external heat reservoirs and the internal dissipation of working fluids. EGM is taken as an objective function for the optimization. The objective function and design parameters are obtained. Optimal performance curves are presented by thermal and electronic parameters. Effects of these parameters on general and optimal performances are investigated. Results are helpful in determining optimal design conditions in real thermoelectric refrigeration systems. 展开更多
关键词 thermoelectric refrigeration system entropy generation minimization finite-time thermodynamics
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两段式冷却在肉牛屠宰工厂设计中的应用
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作者 韩志立 卢维国 《农产品加工》 2017年第10期73-74,共2页
两段式冷却技术已经广泛应用于生猪的屠宰加工,在降低干耗、抑制细菌繁殖和提高肉品品质方面取得了良好的效果。尽管国内外学者对该冷却技术在肉牛屠宰加工中的应用进行了大量研究,但受到牛肉在低温下易产生冷收缩等因素的影响还未能得... 两段式冷却技术已经广泛应用于生猪的屠宰加工,在降低干耗、抑制细菌繁殖和提高肉品品质方面取得了良好的效果。尽管国内外学者对该冷却技术在肉牛屠宰加工中的应用进行了大量研究,但受到牛肉在低温下易产生冷收缩等因素的影响还未能得到广泛应用,通过设置-4℃的快冷温度和对冷间内冷风机的合理布置为该技术在肉牛屠宰中的应用做了进一步探索。 展开更多
关键词 两段式冷却 肉牛屠宰 -4℃快冷间 冷风机布置
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Effect of Disinfection Time on Microbial Content and Quality of Cold Fresh Chicken
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作者 王合叶 赵永富 冯敏 《Agricultural Science & Technology》 CAS 2017年第3期476-477,489,共3页
[Objective] The aim was to provide reference for the production technolo- gy of cold fresh chicken. [Method] Lactic acid was used as the disinfectant in cooling water, so as to study the effect of disinfection time on... [Objective] The aim was to provide reference for the production technolo- gy of cold fresh chicken. [Method] Lactic acid was used as the disinfectant in cooling water, so as to study the effect of disinfection time on the microbial content and quality of cold fresh chicken. [Result] With disinfection of 20 min, the removal rates of the total colonies, coliforms and moulds reached over 95%. As the disinfec- tion time was further extended, it had no significant effect on the removal effects of the microbial content and could affect the tenderness and color of cold fresh chick- en. [Cendusion] The study provides references for the design and optimization of the production process of cold fresh chicken. 展开更多
关键词 Cold fresh chicken Disinfection time Total Colonies COLIFORMS MOULDS Meat Tenderness
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Charcoal Production via Multistage Pyrolysis 被引量:6
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作者 Adetoyese Olajire Oyedun Ka Leung Lam Chi Wai Hui 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第3期455-460,共6页
Interests in charcoal usage have recently been re-ignited because it is believed that charcoal is a muchbetter fuel than wood. The conventional charcoal production consumes a large amount of energy due to the prolonge... Interests in charcoal usage have recently been re-ignited because it is believed that charcoal is a muchbetter fuel than wood. The conventional charcoal production consumes a large amount of energy due to the prolonged heating time and cooling time which contribute to the process completing in one to several days. Wood py-rolysis consists of both endothermic and exothermic reactions as well as the decomposition of the different components at different temperature range (hemicellulose: 200-260℃; cellulose: 240-350℃ and lignin: 280-500℃). Inthis study we propose a multistagepyrolysis which is an approach to carry out pyrolysis with multiple heating stages so as to gain certain processing benefits. We propose a three-stage approach which includes rapid stepwise heating stage to a variable target temperatures of 250 ℃, 300℃, 350 ℃ and 400 ℃, slow and gradual heatingstage to a tinal temperature of 400℃ and adiabatic with cooling stage. The multi-stage pyrolysis process can save 30% energy and the processing time by using a first temperature target of 300 ℃and heating rate of 5℃.min-1 to produce a fixed-carbon yield of 25.73% as opposed to the base case with a fixed-carbon yield of23.18%. 展开更多
关键词 wood pyrolysis charcoal production multistage heating
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Determination of metastable zone and induction time of analgin for cooling crystallization 被引量:7
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作者 Ling Zhou Zhao Wang +3 位作者 Meijing Zhang Mingxia Guo Shijie Xu Qiuxiang Yin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第3期313-318,共6页
The solubility, metastable zone width, and induction time of analgin for unseeded batch cooling crystallization in ethanol–aqueous system were experimentally determined. The solubility data could be well described by... The solubility, metastable zone width, and induction time of analgin for unseeded batch cooling crystallization in ethanol–aqueous system were experimentally determined. The solubility data could be well described by the van't Hoff equation model. The metastable zone width at various cooling rates was measured, and some parameters of nucleation kinetic were calculated using the Ny'vlt theory. Furthermore, the induction period of various temperatures and supersaturation ratios was also measured. According to classical nucleation theory, some nucleation parameters and interfacial energy was calculated through the induction time(t_(ind)) data. Homogeneous nucleation tended to occur when the supersaturation is high, whereas heterogeneous nucleation was more likely to occur when the supersaturation is low. 展开更多
关键词 ANALGIN Cooling crystallization Primary nucleation Metastable zone Induction time
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Characterization of cooling rate and microstructure of Cu Sn melt droplet in drop on demand process 被引量:1
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作者 Yi XU N. ELLENDT +2 位作者 Xing-gang LI V. UHLENWINKEL U. FRITSCHING 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第7期1636-1644,共9页
Different sized single droplets of Cu-6%Sn alloy were prepared by drop on demand(DOD)technique.The secondarydendrite arm spacing was measured and correlated with the droplet cooling rate by a semi-empirical formula.Th... Different sized single droplets of Cu-6%Sn alloy were prepared by drop on demand(DOD)technique.The secondarydendrite arm spacing was measured and correlated with the droplet cooling rate by a semi-empirical formula.The microstructure ofdroplets was observed by optical microscopy(OM)and electro backscatter diffraction(EBSD).The dendrite feature of singledroplets depends on solidification rate,cooling medium and flight distance.When droplets collide with each other at temperaturesbetween solidus and liquidus,the dendrites and grains are refined obviously possibly because the collision enhances the heat transfer.The cooling rate of colliding droplets is estimated to be more than4×104K/s based on a Newton’s cooling model.The dendritesgrow along the colliding direction because of the temperature gradient induced by the internal flow inside the droplets. 展开更多
关键词 impinging droplet secondary dendrite arm spacing cooling rate heat transfer drop on demand
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Influences of Cold Storage at 5℃ for Different Durations on Oviposition of Female Silkworm Moths
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作者 胡仕叶 杨胜特 +4 位作者 田应书 韩世玉 王太兴 王贤玉 黄礼平 《Agricultural Science & Technology》 CAS 2013年第10期1446-1450,1453,共6页
In order to investigate the resistance of female silkworm moths to cold storage and their copulation and oviposition after cold storage, copulation and ovipo- sition experiments of Liangguang 2 silkworms and Guican 1 ... In order to investigate the resistance of female silkworm moths to cold storage and their copulation and oviposition after cold storage, copulation and ovipo- sition experiments of Liangguang 2 silkworms and Guican 1 female silkworm moths were conduced under cold storage at 5 ~C for different durations. The results indi- cated that, after cold storage at 5 ~C with relative humidity of 75%, the resistance of female silkworm moths to cold storage varied with different varieties; to be specific, 9-Fu and 7.Xiang, parent silkworm varieties of Liangguang 2 with ancestry of mul- tivoltinism, were relatively resistant to cold storage, and their copulation capability was still at a high level after cold storage for 72 h. Oviposition capability also varied with different varieties and durations; to be specific, under 5 ~C conditions, between two parent silkworm varieties of Liangguang 2, female silkworm moths of 9-Fu achieved the best results within cold storage duration of 24 h, female silkworm moths of 7.Xiang achieved the best results within cold storage duration of 72 h; be- tween two parent silkworm varieties of Guican 1, female silkworm moths of Xinhang achieved the best results without cold storage, female silkworm moths of 826 achieved the best results within cold storage duration of 48 h. 展开更多
关键词 Liangguang 2 Guican 1 Cold storage oviposition amount Good egg percentage Poor egg percentage
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Performance comparison and analysis of a combined power and cooling system based on organic Rankine cycle 被引量:2
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作者 王志奇 周奇遇 +2 位作者 夏小霞 刘斌 张欣 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第2期353-359,共7页
A novel power and cooling system combined system which coupled organic Rankine cycle(ORC) with vapor compression refrigeration cycle(VCRC) was proposed. R245 fa and butane were selected as the working fluid for the po... A novel power and cooling system combined system which coupled organic Rankine cycle(ORC) with vapor compression refrigeration cycle(VCRC) was proposed. R245 fa and butane were selected as the working fluid for the power and refrigeration cycle, respectively. A performance comparison and analysis for the combined system was presented. The results show that dual-pressure ORC-VCRC system can achieve an increase of 7.1% in thermal efficiency and 6.7% in exergy efficiency than that of basic ORC-VCRC. Intermediate pressure is a key parameter to both net power and exergy efficiency of dual-pressure ORC-VCRC system. Combined system can produce maximum net power and exergy efficiency at 0.85 MPa for intermediate pressure and 2.4 MPa for high pressure, respectively. However, superheated temperature at expander inlet has little impact on the two indicators. It can achieve higher overall COP, net power and exergy efficiency at smaller difference between condensation temperature and evaporation temperature of VCRC. 展开更多
关键词 dual-pressure organic Rankine cycle vapor compression refrigeration waste heat performance analysis
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Metastable State of Clindamycin Phosphate in Cooling Crystallization 被引量:1
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作者 谌怡 高毅颖 +1 位作者 朱亮 王静康 《Transactions of Tianjin University》 EI CAS 2010年第2期142-146,共5页
The metastable state and nucleation kinetics of clindamycin phosphate (CP) in cooling crystallization were studied by metastable zone width (MZW) method and induction time method. By correlating the MZW experimental r... The metastable state and nucleation kinetics of clindamycin phosphate (CP) in cooling crystallization were studied by metastable zone width (MZW) method and induction time method. By correlating the MZW experimental results with temperature, agitation rate and cooling rate, it is found that the correlation result shows good agreement with the change trend of MZW. The critical nucleation parameters were evaluated based on the classical theory of nucleation; both the interfacial tension and the radius of critical nucleus increased with the decrease of relative supersaturation. The effect of supersaturation on the nucleation rate was analyzed. It is indicated that the new phase formation of CP is governed by mononuclear mechanism. 展开更多
关键词 metastable zone induction time NUCLEATION industrial crystallization
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ESTABLISHMENT OF CRITICAL COOLING TIME CRITERION OF WELDING COLD CRACKING
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作者 张文钺 许玉环 +2 位作者 徐德禄 陈邦固 杜则裕 《Transactions of Tianjin University》 EI CAS 1995年第1期5+1-5,共6页
The plate rigid restraint cracking tests (PRRC) have been used to study the welding cold cracking susceptibilities of four kinds of domestic HSLA steels and the effects of diffusive hydrogen content. In welded joints,... The plate rigid restraint cracking tests (PRRC) have been used to study the welding cold cracking susceptibilities of four kinds of domestic HSLA steels and the effects of diffusive hydrogen content. In welded joints, welding heat input, local preheat temperature, restraint intensity and additional stress induced by local preheating on cold cracking susceptibility of steels have been discussed. On the basis of the above research, the critical cooling time criterion tcr of domestic HSLA steels is established. This criterion is proved to be reliable in real application, and has important significance to assess whether the cold cracking occurs under conditions of welding process. 展开更多
关键词 HSLA steel critical cooling time CRITERION
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Effect of airplane transport of donor livers on post-liver transplantation survival
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作者 Yi Huang Gerry MacQuillan +7 位作者 Leon A Adams George Garas Megan Collins Albert Nwaba Linjun Mou Max K Bulsara Luc Delriviere Gary P Jeffrey 《World Journal of Gastroenterology》 SCIE CAS 2016年第41期9154-9161,共8页
AIM To evaluate the effect of long haul airplane transport of donor livers on post-transplant outcomes. METHODS A retrospective cohort study of patients who received a liver transplantation was performed in Perth, Aus... AIM To evaluate the effect of long haul airplane transport of donor livers on post-transplant outcomes. METHODS A retrospective cohort study of patients who received a liver transplantation was performed in Perth, Australia from 1992 to 2012. Donor and recipient characteristics information were extracted from Western Australian liver transplantation service database. Patients were followed up for a mean of six years. Patient and graft survival were evaluated and compared between patients who received a local donor liver and those who received an airplane transported donor liver. Predictors of survival were determined by univariate and multivariate analysis using cox regression.RESULTS One hundred and ninety-three patients received alocal donor liver and 93 patients received an airplane transported donor liver. Airplane transported livers had a significantly lower alanine transaminase(mean: 45 U/L vs 84 U/L, P = 0.035), higher donor risk index(mean: 1.88 vs 1.42, P < 0.001) and longer cold ischemic time(CIT)(mean: 10.1 h vs 6.4 h, P < 0.001). There was a weak correlation between CIT and transport distance(r2 = 0.29, P < 0.001). Mean follow up was six years and 93 patients had graft failure. Multivariate analysis found only airplane transport retained significance for graft loss(HR = 1.92, 95%CI: 1.16-3.17). One year graft survival was 0.88 for those with a local liver and was 0.71 for those with an airplane transported liver. One year graft loss was due to primary graft non-function or associated with preservation injury in 20.8% of recipients of an airplane transported liver compared with 4.6% in those with a local liver(P = 0.027). CONCLUSION Airplane transport of donor livers was independently associated with reduced graft survival following liver transplantation. 展开更多
关键词 Airplane transportation Cold ischemic time Graft survival Donor location Organ damage
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Development of magnetocaloric materials in room temperature magnetic refrigeration application in recent six years 被引量:2
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作者 刘敏 俞炳丰 《Journal of Central South University》 SCIE EI CAS 2009年第1期1-12,共12页
Some magnetocaloric materials were used successfully in magnetic refrigeration application and became one of the critical parts of magnetic refrigeration technology whose delightful progresses were made worldwide in t... Some magnetocaloric materials were used successfully in magnetic refrigeration application and became one of the critical parts of magnetic refrigeration technology whose delightful progresses were made worldwide in the past 30 years. At the same time, the research on giant magnetocaloric materials will accelerate the development of room temperature magnetic refrigeration. In this paper, the new theoretical and experimental investigations on magnetic materials in room temperature application were described, including Gd and its binary and ternary intermetallic compounds, Mn-based compounds, La(Fe13-xMx)-based compounds and manganites. Based on the analysis of hysteresis, corrosion, cost and heat process, the comparison between different families of magnetic materials was discussed. Further research of room temperature magnetic refrigerant was suggested. 展开更多
关键词 magnetic material REFRIGERATION magnetocaloric effect magnetic resistance
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