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
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
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
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
[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
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
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
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
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
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
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
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
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
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
基金Project(ZZYJKT2024-08)supported by the State Key Laboratory of Precision Manufacturing for Extreme Service Performance,ChinaProject(2022JB11GX004)supported by Selection of the best Candidates to Undertake Key Research Projects by Dalian City,ChinaProject(201806835007)supported by China Scholarship Council。
文摘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.
文摘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 .
基金The National Natural Science Foundation of China(No.50846056)
文摘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.
文摘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.
基金Supported by the Jiangsu Agricultural Science and Technology Innovation Foundation(CX(15)1009)~~
文摘[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.
基金Supported by the Hong Kong RGC in form of PhD Fellowship to Adetoyese Olajire Oyedun(PF09-05997)
文摘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%.
基金Supported by the National Natural Science Foundation of China(21206109)China Ministry of Science and Major National Scientific Instrument Development Project(21527812)
文摘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.
基金Project(51301143)supported by the National Natural Science Foundation of ChinaProject(2014M560727)supported by the National Postdoctoral Foundation of China+1 种基金Project(2015GZ0228)supported by the Sichuan Province Science-Technology Support Plan,ChinaProject(2682014CX001)supported by the Science and Technology Innovation Project of SWJTU University,China
文摘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.
基金Supported by Special Fund for Construction of Modern Agricultural Industry Technology System of the Ministry of Agriculture(CARS-22-SYZ26)Innovation Ability Construction Project of Science and Technology Department of Guizhou Province(QKHYSCX[2012]4003)Fund of Guizhou Academy of Agricultural Sciences[QNKH(Fund)2011017]~~
文摘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.
基金Project(12C0379)supported by the Scientific Research Fund of Hunan Province,ChinaProject(13QDZ04)supported by the Scientific Research Foundation for Doctors of Xiangtan University,China
文摘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.
基金Supported by the Program of Introducing Talents of Discipline to Universities (No. B06006)
文摘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.
文摘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.
文摘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.
基金Project(50876082) supported by the National Natural Science Foundation of ChinaProject(IRT0746) supported by the Changjiang Scholars and Innovative Research Team in University
文摘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.