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The Effect of Water Flow Velocity on Heat Collection Performance of Active Heat Storage and Release System for Solar Greenhouses
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作者 Wei Lu Lirui Liang +8 位作者 Dawei Shi Wenjun Peng Yangxia Zheng In-bok Lee Mengyao Li Qichang Yang Jiangtao Hu Xiaopei Tang Chengyao Jiang 《Journal of Electronic Research and Application》 2024年第6期79-88,共10页
In order to explore the influence of water velocity on the heat collection performance of the active heat storage and release system for solar greenhouses,six different flow rates were selected for treatment in this e... In order to explore the influence of water velocity on the heat collection performance of the active heat storage and release system for solar greenhouses,six different flow rates were selected for treatment in this experiment.The comprehensive heat transfer coefficient of the active heat storage and release system at the heat collection stage was calculated by measuring the indoor solar radiation intensity,indoor air temperature and measured water tank temperature.The prediction model of water temperature in the heat collection stage was established,and the initial value of water temperature and the comprehensive heat transfer coefficient were input through MATLAB software.The simulated value of water temperature was compared with the measured value and the results showed that the best heat transfer effect could be achieved when the water flow speed was 1.0 m3h-1.The average relative error between the simulated water tank temperature and the measured value is 2.70-6.91%.The results indicate that the model is established correctly,and the variation trend of water temperature can be predicted according to the model in the heat collection stage. 展开更多
关键词 active heat storage and release Water velocity Coefficient of heat transfer Modeling Solar energy
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Improved sweat gland function during active heating in tennis athletes
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作者 Jeong-Beom Lee Soon-Bok Na Tae-Wook Kim 《Journal of Sport and Health Science》 SCIE 2016年第4期443-447,共5页
Background:Relatively few studies on the peripheral sweating mechanisms of trained tennis athletes have been conducted.The purpose of this study was to compare the sweating capacities of tennis athletes against untra... Background:Relatively few studies on the peripheral sweating mechanisms of trained tennis athletes have been conducted.The purpose of this study was to compare the sweating capacities of tennis athletes against untrained subjects(controls).Methods:Thirty-fi e healthy male volunteers participated including 15 untrained subjects and 20 trained tennis athletes(nationally ranked).Active heat generation was performed for 30 min(running at 60%VO2max) in a climate chamber(temperature,25.0°C ± 0.5°C;relative humidity,60% ± 3%,termed active heating).Sweating data(local sweat onset time,local sweat volume,activated sweat glands,sweat output per gland,whole body sweat loss volume) were measured by the capacitance hygrometer-ventilated capsule method and starch-iodide paper.Mean body temperature was calculated from tympanic and skin temperatures.Results:Local sweat onset time was shorter for tennis athletes(p〈0.001).Local sweat volume,activated sweat glands of the torso and limbs,sweat output per gland,and whole body sweat loss volume were significant y higher for tennis athletes than control subjects after active heating(p〈0.001).Tympanic and mean body temperatures were lower among tennis athletes than controls(p〈0.05).Conclusion:These results indicate that tennis athletes had increased regulatory capacity of their sweat gland function. 展开更多
关键词 activated sweat glands active heating Sweat onset time Sweat output Sweating function Tennis athletes
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Elevated brain temperature under severe heat exposure impairs cortical motor activity and executive function
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作者 Xiang Ren Tan Mary C.Stephenson +4 位作者 Sharifah Badriyah Alhadad Kelvin W.Z.Loh Tuck Wah Soong Jason K.W.Lee Ivan C.C.Low 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期233-244,共12页
Background:Excessive heat exposure can lead to hyperthermia in humans,which impairs physical performance and disrupts cognitive function.While heat is a known physiological stressor,it is unclear how severe heat stres... Background:Excessive heat exposure can lead to hyperthermia in humans,which impairs physical performance and disrupts cognitive function.While heat is a known physiological stressor,it is unclear how severe heat stress affects brain physiology and function.Methods:Eleven healthy participants were subjected to heat stress from prolonged exercise or warm water immersion until their rectal temperatures(T_(re))attained 39.5℃,inducing exertional or passive hyperthermia,respectively.In a separate trial,blended ice was ingested before and during exercise as a cooling strategy.Data were compared to a control condition with seated rest(normothermic).Brain temperature(T_(br)),cerebral perfusion,and task-based brain activity were assessed using magnetic resonance imaging techniques.Results:T_(br)in motor cortex was found to be tightly regulated at rest(37.3℃±0.4℃(mean±SD))despite fluctuations in T_(re).With the development of hyperthermia,T_(br)increases and dovetails with the rising T_(re).Bilateral motor cortical activity was suppressed during high-intensity plantarflexion tasks,implying a reduced central motor drive in hyperthermic participants(T_(re)=38.5℃±0.1℃).Global gray matter perfusion and regional perfusion in sensorimotor cortex were reduced with passive hyperthermia.Executive function was poorer under a passive hyperthermic state,and this could relate to compromised visual processing as indicated by the reduced activation of left lateral-occipital cortex.Conversely,ingestion of blended ice before and during exercise alleviated the rise in both T_(re)and T_(bc)and mitigated heat-related neural perturbations.Conclusion:Severe heat exposure elevates T_(br),disrupts motor cortical activity and executive function,and this can lead to impairment of physical and cognitive performance. 展开更多
关键词 Brain functional activity COGNITION heat stress HYPERTHERMIA Motor function
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Regeneration of waste activated carbon after extracting gold with steam under microwave heating:Optimization using response surface methodology 被引量:2
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作者 左勇刚 张利波 +3 位作者 彭金辉 C.SRINIVASAKANNAN 刘秉国 马爱元 《Journal of Central South University》 SCIE EI CAS 2014年第8期3233-3240,共8页
The technology that waste activated carbon after extracting gold is regenerated with steam under microwave heating was studied. The influence of the activation temperature, activation duration and steam flow rate on i... The technology that waste activated carbon after extracting gold is regenerated with steam under microwave heating was studied. The influence of the activation temperature, activation duration and steam flow rate on iodine adsorption value and regeneration yield of activated carbon was investigated. The response surface methodology (RSM) technique was utilized to optimize the process conditions. The optimum conditions for the preparation of activated carbon are identified to be activation temperature of 831 ℃, activation duration of 40 min and steam flow rate of 2.67 mL/min. The optimum conditions result in an activated carbon with an iodine number of 1048 mg/g and a yield of 40%, and the BET surface area evaluated using nitrogen adsorption isotherm is 1493 m2/g, with total pore volume of 1.242 cm3/g. And the pore structure of activated carbon regenerated is mainly composed of micropores and a small amount of mesopores. 展开更多
关键词 microwave heating STEAM waste activated carbon EXTRACTING response surface methodology
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Short-Time Preparation of NaOH-Activated Carbon from Sugar Cane Bagasse Using Microwave Plasma Heating 被引量:1
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作者 Katsuya Konno Yusuke Oike +4 位作者 Yasutaka Ohba Osamu Sasaki Yasuyuki Takiguchi Kaoru Onoe Tatsuaki Yamaguchi 《Green and Sustainable Chemistry》 2017年第4期259-269,共11页
The microwave induced argon plasma was applied to the preparation of NaOH-activated carbon from sugar cane bagasse. The distinguished feature of the heating technique with this cold plasma is the short operation time.... The microwave induced argon plasma was applied to the preparation of NaOH-activated carbon from sugar cane bagasse. The distinguished feature of the heating technique with this cold plasma is the short operation time. The carbonization and the activation process were finalized in one step within 3 min. The prepared activated carbon with NaOH ratio 3 to bagasse characterized using N2 adsorption of type IV (IUPAC classification) to give specific surface area of 1980 m2/g and mesopore volume of 0.73 ml/g. It also showed a higher specific capacitance of 201 F/g in 1 M H2SO4 solution (with standard three electrodes) than the corresponding one by the conventional heating, previously reported. The other features were the absence of oxygen groups and the presence of carbon centered stable radicals, detected by ESR spectra, on the surface. 展开更多
关键词 BAGASSE Plasma heating NAOH activated Carbon EDLC Free RADICAL
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Analysis of Heat Transfer in Actively Cooled Compound Gun Barrel 被引量:1
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作者 吴斌 夏伟 《Defence Technology(防务技术)》 SCIE EI CAS 2005年第1期29-36,共8页
when a gun fires, a large amount of heat is brought in the barrel. Erosion/wear and security problems(self ignition of the propellant) associated with this high thermal energy have to be solved owing to the use of hig... when a gun fires, a large amount of heat is brought in the barrel. Erosion/wear and security problems(self ignition of the propellant) associated with this high thermal energy have to be solved owing to the use of higher combustion gas temperature for improved cannon performance and firing at the sustained high rates. Barrel cooling technologies are the effective measures for addressing this issue. In view of the importance of having knowledge of the heat flux, an approach to calculate heat flux based on measurements was presented and validated. The calculated heat flux is used as the inner boundary condition for modeling heat transfer in a 155 mm mid-wall cooled compound gun barrel. Theoretical analysis and simulated results show that natural air cooling is dramatically slower than the forced liquid mid-wall cooling, accordingly wear life of actively cooled barrel is increased and barrel overheating is prevented. 展开更多
关键词 热转换 主动冷却 磨损性质 炮管腐蚀
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Global Response to Tropical Diabatic Heating Variability in Boreal Winter 被引量:1
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作者 张 旭 Hai LINt 江 静 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第2期369-380,共12页
Global teleconnections associated with tropical convective activities were investigated, based on monthly data of 29 Northern Hemisphere winters: December, January, February, and March (DJFM). First, EOF analyses w... Global teleconnections associated with tropical convective activities were investigated, based on monthly data of 29 Northern Hemisphere winters: December, January, February, and March (DJFM). First, EOF analyses were performed on the outgoing longwave radiation (OLR) data to characterize the convective ac tivity variability in the tropical Indian Ocean and the western Pacific. The first EOF mode of the convective activity was highly correlated with the ENSO. The second EOF mode had an east–west dipole structure, and the third EOF mode had three convective activity centers. Two distinct teleconnection patterns were identified that were associated, respectively, with the second and third EOF modes. A global primitive equation model was used to investigate the physical mechanism that causes the global circulation anoma lies. The model responses to anomalous tropical thermal forcings that mimic the EOF patterns matched the general features of the observed circulation anomalies well, and they were mainly controlled by linear processes. The importance of convective activities in the tropical Indian Ocean and western Pacific to the extended and longrange forecasting capability in the extratropics is discussed. 展开更多
关键词 diabatic heating TELECONNECTION tropical convective activities
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Effects of Heat Shock Factor AtHsfA1a on Caspase-3 Activity in Arabidopsis thaliana under High Temperature Stress 被引量:2
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作者 Lihong GUO Xuelan ZHANG +2 位作者 Nian LI Ya XU Qiuxia XI 《Agricultural Biotechnology》 CAS 2016年第4期31-33,37,共4页
[ Objective] This study aimed to investigate the effects of heat shock factor AtHsfAla on Caspase-3 activity in Arabidopsis thaliana under high tempera-ture stress, thus revealing the relationship between heat shoc... [ Objective] This study aimed to investigate the effects of heat shock factor AtHsfAla on Caspase-3 activity in Arabidopsis thaliana under high tempera-ture stress, thus revealing the relationship between heat shock factor AtHsfAl a and programmed cell death in A. thaliana. [ Method ] Different genotypes of A. thaliana (AtHsfAla-silenced transgenic and wild-type) seedlings were treated at 42 ℃. According to the fragmentation level of fluorogenic substrate Ac-DEVD- pNA, Caspase-3 activity was determined by spectrophotometry. [ Result] After high temperature treatment, Caspase-3 activity in A. thaliana was enhanced signifi-cantly. Caspase-3 activity in AtHsfAla-si/enced transgenic A. thaliana was higher than that in wild-type A. thaliana, which indicated that AtHsfAla could inhibit Caspase-3 activity in A. thaliana under high temperature stress. [ Conclusion] Under high temperature stress, heat shock factor AtHsfAla might exert inhibitory effects on programmed cell death by reducing Caspase-3 activity. This study provided the basis for clarifying the mechanism of stress resistance in plants. 展开更多
关键词 heat shock factor AtHsfAla High temperature stress Caspase-3 activity
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Solar-heating boosted catalytic reduction of CO_(2) under full-solar spectrum 被引量:2
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作者 Hongjia Wang Yanjie Wang +3 位作者 Lingju Guo Xuehua Zhang Caue Ribeiro Tao He 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第1期131-139,共9页
Catalytic converting CO2 into fuels with the help of solar energy is regarded as‘dream reaction’,as both energy crisis and environmental issue can be mitigated simultaneously.However,it is still suffering from low e... Catalytic converting CO2 into fuels with the help of solar energy is regarded as‘dream reaction’,as both energy crisis and environmental issue can be mitigated simultaneously.However,it is still suffering from low efficiency due to narrow solar-spectrum utilization and sluggish heterogeneous reaction kinetics.In this work,we demonstrate that catalytic reduction of CO2 can be achieved over Au nanoparticles(NPs)deposited rutile under full solar-spectrum irradiation,boosted by solar-heating effect.We found that UV and visible light can initiate the reaction,and the heat from IR light and local surface-plasmon resonance relaxation of Au NPs can boost the reaction kinetically.The apparent activation energy is determined experimentally and is used to explain the superior catalytic activity of Au/rutile to rutile in a kinetic way.We also find the photo-thermal synergy in the Au/rutile system.We envision that this work may facilitate understanding the kinetics of CO2 reduction and developing feasible catalytic systems with full solar spectrum utilization for practical artificial photosynthesis. 展开更多
关键词 CO_(2) reduction Apparent activation energy Reaction kinetics Solar heating Photo-thermal synergy
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Sawtooth Activity in Ohmically Heated Plasma on HT-7 Tokamak 被引量:1
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作者 胡立群 石跃江 +2 位作者 曾立 卫明生 刘胜侠 《Plasma Science and Technology》 SCIE EI CAS CSCD 2001年第1期-,共8页
Sawtooth activity on HT-7 tokamak has been investigated experimentally mainly by using soft x-ray diode array and magnetic probes. Their behaviors and occurrences are correlated closely to the discharge conditions: th... Sawtooth activity on HT-7 tokamak has been investigated experimentally mainly by using soft x-ray diode array and magnetic probes. Their behaviors and occurrences are correlated closely to the discharge conditions: the electron density Ne, the electron temperature Te, the safety factor qa on plasma boundary and wall condition etc. When central line-averaged electron density Ne(0) is over 2.0×1013cm-3 , major sawtooth activity emerges with a period of up to 6.5 ms and a fluctuation amplitude of up to 2-30 % of SXR radiation signal. In some cases such as the safety factor between 4.2-4.7 and Zeff=3.0-6.0, a monster sawtooth activity often emerges without apparent deterioration of plasma confinement and without major disruption. During these events, abundant MHD phenomena are observed including partial sawtooth oscillations. In this paper, the observed sawtooth behaviors and their dependence on the and their dependence density Ne and wall condition in ohmically heated plasma are introduced, the results are discussed and presented. 展开更多
关键词 ICRF LHCD Sawtooth activity in Ohmically heated Plasma on HT-7 Tokamak HT MHD very
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Novel heat shock protein Hsp70L1 activates dendritic cells and acts as a Th1 polarizing adjuvant 被引量:1
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作者 WanT ZhouX ChenG AnH ChenT ZhangW LiuS JiangY YangF WuY CaoX 《第二军医大学学报》 CAS CSCD 北大核心 2005年第7期771-771,共1页
Heat shock proteins (HSPs) are reported to act as effective adjuvants to elicit anti-tumor and anti-infection immunity. Here, we report that Hsp70-like protein 1 (Hsp70L1), a novel HSP derived from human dendritic cel... Heat shock proteins (HSPs) are reported to act as effective adjuvants to elicit anti-tumor and anti-infection immunity. Here, we report that Hsp70-like protein 1 (Hsp70L1), a novel HSP derived from human dendritic cells (DCs), has potent adjuvant effects that polarize responses toward Th1. With a calculated molecular weight of 54.8 kDa, Hsp70L1 is smaller in size than Hsp70 but resembles it both structurally and functionally. Hsp70L1 shares common receptors on DCs with Hsp70 and can interact with DCs, promoting DC maturation and stimulating secretion of the proinflammatory cytokines interleukin 12p70 (IL-12p70), IL-1beta, tumor necrosis factor-alpha (TNF-alpha), and the chemokines IP-10, macrophage inflammatory protein-1alpha (MIP-1alpha), MIP-1beta, and normal T cell expressed and secreted (RANTES). The induction of interferon-gamma-inducible protein 10 (IP-10) secretion by Hsp70L1 is not shared by Hsp70, and other functional differences include more potent stimulation of DC IL-12p70, CC-chemokine, and CCR7 and CXCR4 expression by Hsp70L1. Immunization of mice with the hybrid peptide Hsp70L1-ovalbumin(OVA)(257-264) induces an OVA(257-264)-specific Th1 response and cytotoxic T lymphocyte (CTL) that results in significant inhibition of E.G7-OVA tumor growth. The ability of Hsp70L1 to activate DCs indicates its potential as a novel adjuvant for use with peptide immunizations; the Hsp70L1 antigen peptide hybrid may serve as a more effective vaccine for the control of cancer and infectious diseases. 展开更多
关键词 Th heat Novel heat shock protein Hsp70L1 activates dendritic cells and acts as a Th1 polarizing adjuvant
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Investigation into the surface active groups of coal 被引量:1
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作者 徐精彩 薛韩玲 +2 位作者 邓军 文虎 张辛亥 《Journal of Coal Science & Engineering(China)》 2001年第1期88-96,共9页
The oxidation heat of coal is the direct reason leading to coal spontaneous combustion. When coal is exposed in oxygen atmosphere, the physical adsorption and chemisorption happened, and then which resulting chemical ... The oxidation heat of coal is the direct reason leading to coal spontaneous combustion. When coal is exposed in oxygen atmosphere, the physical adsorption and chemisorption happened, and then which resulting chemical reaction followed heat between coal and oxygen. Owing to the complexity and uncertain of molecular structure of coal,it was only reduced that bridge bonds, side chains and O 2 containing functional groups in coal may be prone to oxidation in last year, but not to deeply investigate into the structures and the type of the active radicals. In this paper, according to the last achievements in coal structure research, the hypomethylether bond, hypoalkyl bond of α carbon atom with hydroxyl and α carbon atom with hypomethy side chain and hypomethyl bonds linking up two aromatic hydrocarbon in bridge bonds, and methoxy,aldehyde and alkyls of α carbon atom with hydroxy in side bonds are inferred to be free radical easily to lead to oxidize coal under the ambient temperature and pressure. The order from strong to weak of oxide activation of the seven surface active groups is aldehyde side chains, hypomethylether bonds, hypoalkyl bonds of α carbon atom with hydroxyl, hypoalkyl bonds of α carbon atom with hypomethyl, hypomethyl bonds linking up two aromatic hydrocarbon,methoxy, alkyls side chains of α carbon atom with hydroxyl. Because of the two unsaturated molecular tracks of O 2, unpaired electron clouds of the part of surface active groups of coal enter molecular tracks of O 2 to lead to chemisorb on the conjugate effect and induced effect of surface active groups, and then chemical reaction followed heat happens in them. On the basis of change of bond energy, weighted average method is adopted to count the reaction heat value of each mol CO,CO 2 and H 2O. The property of coal spontaneous combustion is different for the different number and oxidability of the active structure in the coal resulting in the different oxidation heat. 展开更多
关键词 coal spontaneous combustion surface active group oxidation reaction reactive heat
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Heat and mass flux estimation of modern seafloor hydrothermal activity
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作者 ZHAI Shikui WANG Xingtao YU Zenghui 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第6期43-51,共9页
Research on heat and mass flux yielded by modern seafloor hydrothermal activity is very important, because it is involved not only in the base of ocean environment research, but also in the historical evolution of sea... Research on heat and mass flux yielded by modern seafloor hydrothermal activity is very important, because it is involved not only in the base of ocean environment research, but also in the historical evolution of seawater properties. Currently, estimating heat flux is based on the observation data of hydrothermal smokers, low-temperature diffusive flow and mid-ocean ridge mainly. But there are some faults, for example, there is lack of a concurrent conductive item in estimating the heat flux by smokers and the error between the half-space cooling model and the observation data is too large. So, three kinds of methods are applied to re-estimating the heat flux of hydrothermal activity resepectively, corresponding estimation is 97. 359 GW by hydrothermal smoker and diffusive flow, 84.895 GW by hydrothermal plume, and 4. 11 TW by exponential attenuation method put forward by this paper. Research on mass flux estimation is relatively rare, the main reason for this is insufficient field observation data. Mass fluxes of different elements are calculated using hydrothermal vent fluid data from the TAG hydrothermal area on the Mid-Atlantic Ridge for the first time. Difference of estimations by different methods reflects the researching extent of hydrothermal activity, and systematically in - situ observation will help to estimate the contribution of hydrothermal activity to ocean chemical environment, ocean circulation and global climate precisely. 展开更多
关键词 hydrothermal activity heat flux mass flux exponential attenuation method
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Monster Sawtooth Activity in Ohmically Heated HT-7 Plasma
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作者 胡立群 石跃江 刘胜侠 《Plasma Science and Technology》 SCIE EI CAS CSCD 2001年第5期977-984,共8页
Experimental properties of monster sawtooth activities in ohmic HT-7 plasma are presented in this paper. The monster sawtooth activities belong to global fluctuations and are characterized with a series of large core ... Experimental properties of monster sawtooth activities in ohmic HT-7 plasma are presented in this paper. The monster sawtooth activities belong to global fluctuations and are characterized with a series of large core collapses on SXR intensity traces with a long period, a large amplitude fluctuation and a large inversion radius. However, they emerge without apparent deterioration of plasma confinement and without major plasma disruption. During the events, long partial sawtooth collapses and abundant MHD phenomena are also observed. 展开更多
关键词 activITY MHD HT Monster Sawtooth activity in Ohmically heated HT-7 Plasma mode
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Effects of heat on the biological activity of wild Cordyceps sinensis
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作者 Pengkai Wu Zhi Tao +4 位作者 Huafeng Liu Guixiang Jiang Changhua Ma Chunmei Wang Di Geng 《Journal of Traditional Chinese Medical Sciences》 2015年第1期32-38,共7页
Background:Current methods of extending the storage time of wild Cordyceps sinensis adversely affect the nutritive and medicinal value of the product.Thus,this study was designed to investigate the effects of heat tre... Background:Current methods of extending the storage time of wild Cordyceps sinensis adversely affect the nutritive and medicinal value of the product.Thus,this study was designed to investigate the effects of heat treatment,a relatively safe storage extension method,on the biological activity of wild C.sinensis.Methods:Samples were heated to 60,80,or 100℃ for 15,30,or 60 minutes.SOD activity in wild C.sinensis before and after heating was assayed using a standard colorimetric assay.Deoxyribonuclease (DNase) activity was measured using the plasmid-nicking assay.Cordycepin content was analyzed using HPLC.Polysaccharide content was measured using the phenol sulfuric method.The Student's t-test was used for comparison.Results:After heating at 60,80,100℃ for 15,30,60 minutes,respectively,no significant reduction in DNase activity or polysaccharide dissolution was noted (P >.05).Interestingly,heating at 80℃ for 30 minutes led to a significant increase in the SOD activity of C.sinensis (P <.05).In addition,heating at 60℃ for 60 minutes or at 80℃ for 15 minutes significantly increased cordycepin dissolution (P <.05).Other heat treatments had no significant effects on SOD activity or cordycepin dissolution (P >.05).Conclusions:These results suggested that heat treatment does not adversely affect SOD or DNase activity,polysaccharide content,or cordycepin dissolution.Thus,heat treatment might be a safe processing method to extend the storage time of wild C.sinensis without compromising biological activity. 展开更多
关键词 Cordyceps sinensis heat treatment SOD activity DNase activity CORDYCEPIN
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Effects of Mitogen-activated Protein Kinase Signal Pathway on Heat Shock Protein 27 Expression in Human Lens Epithelial Cells Exposed to Sodium Salicylate in vitro 被引量:2
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作者 王智 高瑞莹 +2 位作者 黄渝侃 田博 周龑莉 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2009年第3期377-382,共6页
The roles of mitogen-activated protein kinase (MAPK) signal pathway in sodium salieylate-induced expression of heat shock protein 27 (HSP27) in human lens epithelial cells (HLECs-B3) in vitro were investigated. ... The roles of mitogen-activated protein kinase (MAPK) signal pathway in sodium salieylate-induced expression of heat shock protein 27 (HSP27) in human lens epithelial cells (HLECs-B3) in vitro were investigated. HLECs-B3 were incubated in the fresh media containing sodium salicylate at different concentrations for different durations, and allowed to be recovered in fresh medium without sodium salicylate for different durations with or without pretreatment with p38MAPK inhibitor (SB203580), ERK1/2 inhibitor (PD98059) and JNK/SAPK inhibitor (SP600125). The expression of P38MAPK, ERK1/2, JNK/SAPK, phosphorylated P38MAPK, phosphorylated ERK1/2, phosphorylated JNK/SAPK and HSP27 was detected by Western blot. The expression of HSP27 mRNA and protein was detected by RT-PCR and immunohistochemistry respectively. It was found there was only weak expression of HSP27 in normal HLECs. The expression of HSP27 was not detectable in HLECs-B3 that were exposed to sodium salicylate (55 retool/L) for 1-5 h. It was indicated that recovery from sodium salicylate (〉35 mmol/L) significantly increased the synthesis of HSP27. The expression of HSP27 was up-regulated in HLECs-B3 under sodium salicylate recovery for 3 h, reached the peak level for 6 h, and returned to the level of control cells by 24 h. Activation of P38MAPK from sodium salicylate stimulation occurred at 30th rain, and increased significantly at 1st h, then declined and renamed to baseline level at 3rd h under sodium salicylate recovery. Activation of ERK1/2 occurred at 1st h and reached the peak level at 6th h under sodium salicylate recovery. However, JNK/SAPK was inactivated by sodium salicylate. The expression of HSP27 could be down-regulated with the pretreatment of SB203580 and PD98059 jointly. It is concluded that sodium salicylate can induce the expression of HSP27 in HLECs-B3. The effects are mediated, at least in part, through the activation of P38MAPK and ERK1/2 signaling pathway. 展开更多
关键词 sodium salicylate human lens epithelial cells mitogen-activated protein kinase heat shock protein
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Clinical effect of enriching qi, activating blood circulation, clearing away dampness and heat combined with western medicine in the treatment of idiopathic membranous nephropathy: A meta-analysis
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作者 Zheng-Mei Zhang Zi-Long Shen +1 位作者 Mei-Jie Wang Jing Li 《Journal of Hainan Medical University》 2022年第10期33-41,共9页
Objective:To systemically review the efficacy and safety about the method of enriching qi,activating blood circulation,clearing away dampness and heat combined with western medicine in the therapy of patients with idi... Objective:To systemically review the efficacy and safety about the method of enriching qi,activating blood circulation,clearing away dampness and heat combined with western medicine in the therapy of patients with idiopathy membranous nephropathy(IMN).Methods:We collected the randomized controlled trials(RCTs)of enriching qi,activating blood circulation,clearing away dampness and heat for the treatment of IMN from Pub Med,The Cochrane Library,Medline,China National Knowledge Infrastructure(CNKI),China Biology Medicine disc(CBM),Wanfang Data and Wiper Databases.Bias of risk of retrieval literature was evaluated according to Cochrane Collaboration standard,and Review Manager 5.3 software was used for statistical analysis.Results:Fourteen trials(836 participants)were included in the meta-analysis.This kind of traditional Chinese method combined with western medicine in the treatment of IMN exerted statistical differences in reducing 24-hour urinary protein[WMD=-0.97,95%CI(-1.30,-0.65),Z=5.86(P<0.00001)]and elevating serum albumin[WMD=3.83,95%CI(2.10,5.57),Z=4.33,P<0.0001],lowering serum cholesterol[WMD=-0.82,95%CI(-1.08,-0.56),Z=6.18,P<0.00001],triglycerides[WMD=-0.39,95%CI(-0.67,-0.11),Z=2.77,P=0.006]and reducing the risk of adverse events[OR=0.29,95%CI[0.16,0.50],Z=4.35,P<0.0001]in the patients with IMN as compared with controls.However,there was no statistically significant difference between the method and controls when combining all trials in serum creatinine[WMD=-5.52,95%CI(-18.06,7.03),Z=0.86,P=0.39],when combining all trials in urea nitrogen[WMD=-0.90,95%CI(-2.22,0.41),Z=1.35,P=0.18].Conclusion:The method of enriching qi,activating blood circulation,clearing away dampness and heat combined with western medicine exerts certain advantages and better safety in treating patients with IMN.However,for the inferiority of the included studies,the conclusion still needs high-quality and large-sample prospective randomized controlled trials to verify. 展开更多
关键词 Idiopathic membranous nephropathy META-ANALYSIS Enriching qi activating blood circulation Clearing away dampness and heat
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Sodium-Modified Fluorapatite: A Mild and Efficient Reusable Catalyst for the Synthesis of <i>α,α</i>’-Bis(Substituted Benzylidene) Cycloalkanones under Conventional Heating and Microwave Irradiation
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作者 Bahija Mounir Fathallaah Bazi +2 位作者 Abddelfetah Mounir Mohamed Zahouily Hamid Toufik 《Green and Sustainable Chemistry》 2018年第2期156-166,共11页
A versatile and environmentally friendly method for α,α’-bis(substituted ben-zylidene) cycloalkanones has been developed using a heterogeneous catalysis technology. We have synthesized a series of the α,α’-bis(s... A versatile and environmentally friendly method for α,α’-bis(substituted ben-zylidene) cycloalkanones has been developed using a heterogeneous catalysis technology. We have synthesized a series of the α,α’-bis(substituted benzylidene) cycloalkanones, a biologically important class of compounds, via the cross aldol condensation between arylaldehydes and cycloketones using sodium-modified fluorapatite (Na/FAP) as a highly efficient solid catalyst under conventional heating in aqueous media and solventless conditions under microwave. Catalyst reuse, ease of separation of the pure product, and high yields are some of the unique features of this process. Shorter reaction times (4 - 7 min) and higher yields (80% - 94%) were achieved under microwave irradiation conditions. 展开更多
关键词 Green Chemistry α α’-Bis(Substituted Benzylidene) CYCLOALKANONES Microwaves Irradiation Conventional heating Aqueous Media FLUORAPATITE activated by SODIUM Nitrate (Na/FAP)
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High adsorption selectivity of activated carbon and carbon molecular sieve boosting CO_(2)/N_(2) and CH_(4)/N_(2) separation
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作者 Siang Chen Wenling Wu +4 位作者 Zhaoyang Niu Deqi Kong Wenbin Li Zhongli Tang Donghui Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期282-297,共16页
Flue gas and coal bed methane are two important sources of greenhouse gases.Pressure swing adsorption process has a wide range of application in the field of gas separation,and the selection of adsorbent is crucial.In... Flue gas and coal bed methane are two important sources of greenhouse gases.Pressure swing adsorption process has a wide range of application in the field of gas separation,and the selection of adsorbent is crucial.In this regard,in order to assess the better adsorbent for separating CO_(2) from flue gas and CH_(4) from coal bed methane,adsorption isotherms of CO_(2),CH_(4) and N_(2) on activated carbon and carbon molecular sieve are measured at 303.15,318.15 and 333.15 K,and up to 250 kPa.The experimental data fit better with Langmuir 2 compared to Langmuir 3 and Langmuir-Freundlich models,and Clausius-Clapeyron equation was used to calculate the isosteric heat.Both the order of the adsorbed amount and the adsorption heat on the two adsorbents are CO_(2)>CH_(4)>N_(2).The adsorption kinetics are calculated by the pseudo-first kinetic model,and the order of adsorption rates on activated carbon is N_(2)-CH_(4)>CO_(2),while on carbon molecular sieve,it is CO_(2)-N_(2)>CH_(4).It is shown that relative molecular mass and adsorption heat are the primary effect on kinetics for activated carbon,while kinetic diameter is the main resistance factor for carbon molecular sieve.Moreover,the adsorption selectivity of CH_(4)/N_(2) and CO_(2)/N_(2) were estimated with the ideal adsorption solution theory,and carbon molecular sieve performed best at 318.15 K for both CO_(2) and CH_(4) separation.The study suggested that activated carbon is a better choice for separating flue gas and carbon molecular sieve can be a strong candidate for separating coal bed methane. 展开更多
关键词 activated carbon Carbon molecular sieve Adsorbent evaluation Adsorption equilibrium and kinetics heat of adsorption SELECTIVITY
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Surface Cleaning or Activation?Control of Surface Condition Prior to Thermo-Chemical Heat Treatment
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作者 BrigitteHaase JuanDong JensHeinlein 《材料热处理学报》 EI CAS CSCD 北大核心 2004年第5期343-348,共6页
Actual heat treatment processes must face increasing specifications with reference to process quality, safety and results in terms of reproducibility and repeatability. They can be met only if the parts’ surface cond... Actual heat treatment processes must face increasing specifications with reference to process quality, safety and results in terms of reproducibility and repeatability. They can be met only if the parts’ surface condition is controlled during manufacturing and, especially, prior to the treatment. An electrochemical method for the detection of a steel part’s surface condition is presented, together with results, consequences, and mechanisms concerning surface pre-treatment before the thermochemical process. A steel surface’s activity or passivity can be detected electrochenucalry, independently from the chemical background. The selected method was the recording of potential vs. time curves at small constant currents, using a miniaturized electrochemical cell, a (nearly) non-destructive electrolyte and a potentio-galvanostatic setup. The method enables to distinguish types of surface contamination which do not interfere with the thermochemical process, from passive layers which do and must be removed. Whereas some types of passive layers can be removed using conventional cleaning processes and agents, others are so stable that their effects can only be overcome by applying an additional activation pre-treatment, e.g. oxynitriding. 展开更多
关键词 热化学热处理 表面状况 表面清理 表面活化
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