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Research on the Method of Heat Preservation and Heating for the Drilling System of Polar Offshore Drilling Platform
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作者 Yingkai Dong Chaohe Chen +2 位作者 Guangyan Jia Lidai Wang Jian Bai 《Energy Engineering》 EI 2024年第5期1173-1193,共21页
This study investigates the heat dissipation mechanism of the insulation layer and other plane insulation layers in the polar drilling rig system.Combining the basic theory of heat transfer with the environmental requ... This study investigates the heat dissipation mechanism of the insulation layer and other plane insulation layers in the polar drilling rig system.Combining the basic theory of heat transfer with the environmental requirements of polar drilling operations and the characteristics of polar drilling processes,we analyze the factors that affect the insulation effect of the drilling rig system.These factors include the thermal conductivity of the insulation material,the thickness of the insulation layer,ambient temperature,and wind speed.We optimize the thermal insulation material of the polar drilling rig system using a steady-state method to measure solid thermal conductivity.By analyzing the distribution of temperature in space after heating,we optimize the distribution and air outlet angle of the heater using Fluent hydrodynamics software.The results demonstrate that under polar conditions,polyisocyanurate with stable thermodynamic properties is selected as the thermal insulation material.The selection of thermal insulation material and thickness significantly affects the thermal insulation effect of the system but has little effect on its heating effect.Moreover,when the air outlet angle of the heater is set to 32.5°,the heating efficiency of the system can be effectively improved.According to heat transfer equations and heat balance theory,we determine that the heating power required for the system to reach 5°C is close to numerical simulation. 展开更多
关键词 Polar drilling drilling system fluid dynamics heat preservation and heating numerical simulation
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Observation of the Effects of Anesthesia Recovery Nursing Combined with Heat Preservation Measures in Patients Undergoing General Anesthesia Surgery
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作者 Zhilong Sun Yulin Bu 《Journal of Clinical and Nursing Research》 2024年第7期91-96,共6页
Objective:To observe the application effects of anesthesia recovery nursing with heat preservation measures in patients undergoing general anesthesia surgery.Methods:300 cases of general anesthesia surgery patients in... Objective:To observe the application effects of anesthesia recovery nursing with heat preservation measures in patients undergoing general anesthesia surgery.Methods:300 cases of general anesthesia surgery patients in our hospital from March 2023 to February 2024 were selected and divided into the control group and the observation group according to the random number table method,each with 150 cases.The control group adopted conventional care,while the observation group was given anesthesia recovery care and heat preservation measures on the basis of conventional care.The wake-up time,extubation time,hospitalization time,and the incidence of adverse reactions were compared between the two groups and statistically analyzed.Results:The wake-up time of patients in the control group was 9.71±1.20 hours,and that of the observation group was 6.51±1.02 hours,with statistically significant differences(P<0.05);the extubation times of patients in the observation group and the control group after awakening were 8.52±0.41 min and 10.42±1.12 min,respectively,with statistically significant differences(P<0.05)The hospital stay after the operation in the observation group and the control group was 32.91±4.71 days and 37.24±3.34 days respectively,and the difference was statistically significant(P<0.05),and the incidence rate of adverse reactions after extubation in the observation group(3.33%)was significantly lower than that in the control group(10.00%)(P<0.05).Conclusion:In general anesthesia surgery patients,the implementation of anesthesia recovery nursing with heat preservation measures can significantly improve the physical condition of patients,effectively shorten the duration of surgery and patients’wake-up time,and improve their quality of life,which is worthy of clinical promotion and application. 展开更多
关键词 Anesthesia recovery nursing heat preservation General anesthesia
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Shelf-cultivation of Strawberry with Mulch and Heat Preservation Technology with Natural Energy
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作者 霍恒志 陈金玉 +4 位作者 朱庆峰 万春雁 陈丙义 李金凤 糜林 《Agricultural Science & Technology》 CAS 2015年第7期1540-1543,共4页
It is proved that the treatment with white mulch and black thin films per- formed the best in terms of heat preservation in cultivation of strawberry with shelves. In winter, drip irrigation performed significantly in... It is proved that the treatment with white mulch and black thin films per- formed the best in terms of heat preservation in cultivation of strawberry with shelves. In winter, drip irrigation performed significantly in transporting hot water through solar energy. The combination of the two methods resolved the issue of heat preservation difficulty and guaranteed growth of strawberry in winter. 展开更多
关键词 STRAWBERRY Shelf-cultivation MULCH Natural energy heat preservation technology
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Effects of Street-Bottom and Building-Roof Heating on Flow in Three-Dimensional Street Canyons 被引量:3
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作者 Jae-Jin KIM Jong-Jin BAIK 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第3期513-527,共15页
Using a computational fluid dynamics (CFD) model, the effects of street-bottom and building-roof heating on flow in three-dimensional street canyons are investigated. The building and street-canyon aspect ratios are... Using a computational fluid dynamics (CFD) model, the effects of street-bottom and building-roof heating on flow in three-dimensional street canyons are investigated. The building and street-canyon aspect ratios are one. In the presence of street-bottom heating, as the street-bottom heating intensity increases, the mean kinetic energy increases in the spanwise street canyon formed by the upwind and downwind buildings but decreases in the lower region of the streamwise street canyon. The increase in momentum due to buoyancy force intensifies mechanically induced flow in the spanwise street canyon. The vorticity in the spanwise street canyon strengthens. The temperature increase is not large because relatively cold above-roof-level air comes into the spanwise street canyon. In the presence of both street-bottom and building-roof heating, the mean kinetic energy rather decreases in the spanwise street canyon. This is caused by the decrease in horizontal flow speed at the roof level, which results in the weakening of the mean flow circulation in the spanwise street canyon. It is found that the vorticity in the spanwise street canyon weakens. The temperature increase is relatively large compared with that in the street-bottom heating case, because relatively warm above-roof-level air comes into the spanwise street canyon. 展开更多
关键词 street canyon flow CFD model street-bottom heating building-roof heating mean kineticenergy vorticity
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Cryopreservation-induced decrease in heat-shock protein 90 in human spermatozoa and its mechanism 被引量:14
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作者 Wen-Lei CAO, Yi-Xin WANG, Zu-Qiong XIANG, Zheng LI Shanghai Institute of Andrology, Renji Hospital, Shanghai Second Medical University, Shanghai 200001, China 《Asian Journal of Andrology》 SCIE CAS CSCD 2003年第1期43-46,共4页
<abstract>Aim: To study the protein changes of spermatozoa associated with sperm motility during sperm cryopreservation and its mechanism. Methods: In 18 healthy men, the seminal sperm motility and HSP90 levels ... <abstract>Aim: To study the protein changes of spermatozoa associated with sperm motility during sperm cryopreservation and its mechanism. Methods: In 18 healthy men, the seminal sperm motility and HSP90 levels were studied before and after cryopreservation using SDS-PAGE, Western blotting and computerized image analysis. Results: The sperm motility declined significantly after cryopreservation (P<0.01). The average grey level and the integrated grey level of sperm HSP90 before cooling were 34.1±3.2 and 243.0±21.6, respectively, while those after thawing were 23.2±2.5 and 105.7±28.5, respectively. Both parameters were decreased significantly (P<0.01). No HSP90 was found in the seminal plasma before and after cryopreservation. Conclusion: HSP90 in human spermatozoa was decreased substantially after cryopreservation. This may result from protein degradation, rather than leakage into the seminal plasma. 展开更多
关键词 human spermatozoa seminal plasma heat-shock proteins 90 western blotting sperm preservation image analysis
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Application of “soft canning” heat preservation technique in the superalloy forging process
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作者 WANG Zixing CHEN Guosheng +1 位作者 ZHOU Dianhua WANG Qingzeng 《Baosteel Technical Research》 CAS 2011年第4期21-24,共4页
The "soft canning" heat preservation technique is invented by Baoshan Iron & Steel Co., Ltd. (Hereafter referred to Baosteel), using the flexible insulation material which can be stuck on the surface of the heate... The "soft canning" heat preservation technique is invented by Baoshan Iron & Steel Co., Ltd. (Hereafter referred to Baosteel), using the flexible insulation material which can be stuck on the surface of the heated ingot or billet in the superalloy thermal process. This adhesive insulation material can reduce the temperature drop of the ingot or billet during the transferring or hot working process, and can deform with the billet without dropping. The surface temperature drop can be effectively reduced, so the products can be obtained a good surface quality and the structural uniformity can be improved. The technique is applied to hard-wrought superalloy forging of cogging, superalloy rods finished forging fire and superalloy hot die forging processing,and good results have been achieved. 展开更多
关键词 soft canning SUPERALLOY heat preservation forging
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Performance Comparison and Analysis of Heating and Ventilation of Two Kinds of Roof Solar Collectors
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作者 翟晓强 王如竹 代彦军 《Journal of Shanghai Jiaotong university(Science)》 EI 2004年第3期69-74,共6页
Two roof solar collectors (RSCs), conventional single pass RSC and new double pass RSC, were compared. The new roof solar collector, which is formed by integrating a double pass solar air collector with the roof of th... Two roof solar collectors (RSCs), conventional single pass RSC and new double pass RSC, were compared. The new roof solar collector, which is formed by integrating a double pass solar air collector with the roof of the building, can be operated more efficiently for space heating in winter, and for natural ventilation in other seasons. To evaluate the performances of the two RSCs for both space heating and natural ventilation, a single traditional Chinese style house, on which the two RSCs will be mounted, was developed. The efficiency of solar energy conversion for the new RSC is higher than that of the single pass one by 10% on average, and the ventilation rate contributed by natural ventilation for the new RSC can be improved to a great extent for most cases, indicating that the new RSC is superior to the single pass one from the viewpoint of both space heating and natural ventilation. The new RSC is more potential for improving indoor thermal environment and energy saving of buildings. 展开更多
关键词 solar energy roof heatING natural ventilation energy saving of building
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Dual-Roof Solar Greenhouse—A Novel Design for Improving the Heat Preserving Capacity in Northern China 被引量:1
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作者 Lilong Chai Baoju Wang +2 位作者 Mingchi Liu Zhanhui Wu Yong Xu 《Natural Resources》 2014年第12期681-686,共6页
Dual-roof solar greenhouse, a new style of solar greenhouse, was designed in this study intending to reduce heat loss in cold time and improve land use efficiency in Beijing, the Capital city of China. Designing and a... Dual-roof solar greenhouse, a new style of solar greenhouse, was designed in this study intending to reduce heat loss in cold time and improve land use efficiency in Beijing, the Capital city of China. Designing and applying the dual-roof greenhouse in metropolitan area had dual effects of saving energy and enhancing land use efficiency. According to the monitoring study and analysis conducted in winter of 2012, the averaged night temperature of south room was about 12.1°C in December, which was satisfying for growing average leaf vegetables. Total energy saved by dual-roof in whole winter was quantified as 1.1 × 107 MJ&#46yr-1 (winter), potentially about 37.4 t coal was saved in Beijing area during whole winter-growing period. Considering the application of north room, the land use efficiency was improved by 62.5% in dual-roof solar greenhouse. 展开更多
关键词 Agricultural Resource Dual-roof GREENHOUSE Solar Energy Land Use Efficiency heat Storage
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Performance of Thermal Insulation of Different Composite Walls and Roofs Materials Used for Energy Efficient Building Construction in Iraq
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作者 Ahmed Mustaffa Saleem Abdullah A.Badr +1 位作者 Bahjat Hassan Alyas Omar Rafae Alomar 《Frontiers in Heat and Mass Transfer》 EI 2024年第4期1231-1244,共14页
This study numerically involves the performance of thermal insulation of different types of composite walls and roofs to demonstrate the best model that can be used for energy-efficient building construction in Iraq.T... This study numerically involves the performance of thermal insulation of different types of composite walls and roofs to demonstrate the best model that can be used for energy-efficient building construction in Iraq.The mathematical model is solved by building its code using the Transmission Matrix Method in MATLAB software.The weather data of 21st July 2022 in Baghdad City/Iraq is selected as a test day.The wall types are selected:the first type consists of cement mortar,brick,and gypsum,the second type consists of cement mortar,brick,gypsum,and plaster and the third type consists of cement mortar,brick,gypsum,air cavity,and sheathing timber.The roof types are chosen:the first type consists of reinforced concrete,gypsum,and plaster,and the second type consists of the precast concrete flag,river sand,tar,reinforced concrete,gypsum,and plaster.The obtained solutions are compared with previous studies for the same city but with different types of walls and roofs.The findings display that the second and third types of walls reduce the entry heat flux by 4%and 10%as compared to the first type of wall.Also,the results indicate that the second type of roof reduces the entry heat flux by 21%as compared to the first type of roof.The results confirm that the best models of walls and roofs in Iraq are the third and second types,respectively,as compared to other models and hence,the performance of insulation material strongly depends on the materials used while building them. 展开更多
关键词 Thermal insulation energy gain composites walls and roofs heat flux transmission matrix method
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Arrangement of Multirow Solar Collector Array on Limited Roof Width
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作者 PU Shaoxuan XIA Chaofeng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2010年第4期76-82,共7页
At the limited roof north-south (N-S) width of a building, for the array with multirow collectors based on no shading at winter solstice noon and sloped at latitude, this paper studied the shading and the radiant en... At the limited roof north-south (N-S) width of a building, for the array with multirow collectors based on no shading at winter solstice noon and sloped at latitude, this paper studied the shading and the radiant energy striking on solar collector array. Based on Kunming solar radiation data, the annual and monthly solar radiant energy striking on multi-array collectors was analyzed and estimated, from no shading to partial shading by adding 1-3 collector row, at the slopes of 10°, 15°, 20°, 25°, 30°, 35° and 40°, respectively. The results showed that properly increasing the row number by reducing the slope of collectors was reasonable in order to get more annual radiant energy. Adding 1 row at 10° of slope was economical for Kunming, based on the 5-row array at 25°. And adding collector row by 20% at 10° of slope could increase the radiant energy striking on the array by 19%. 展开更多
关键词 limited roof width solar water heating system multirow collector array optimizing design
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废旧硅酸铝保温材料高值再利用技术在炼油装置中的应用
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作者 王鑫 《现代化工》 CAS CSCD 北大核心 2024年第S01期289-293,共5页
石油化工企业中的设备和管道在每次检维修时都会拆除更换大量的废旧硅酸铝棉保温隔热材料,废旧的硅酸铝棉材料一般按工业固废进行填埋处理,不能从根本上消除其对周边环境和土壤的危害,同时更换新保温材料也会增加企业的成本。通过研究... 石油化工企业中的设备和管道在每次检维修时都会拆除更换大量的废旧硅酸铝棉保温隔热材料,废旧的硅酸铝棉材料一般按工业固废进行填埋处理,不能从根本上消除其对周边环境和土壤的危害,同时更换新保温材料也会增加企业的成本。通过研究废旧硅酸铝棉的高值资源综合再利用情况,建立了废旧硅酸铝棉及其制品可回用的评价标准,使得废旧硅酸铝棉及其制品降级处理改成制备陶瓷纳米纤维管壳(再用),从根本上解决了废弃保温材料处置难题,提升了资源综合利用效率。该技术已用于某公司炼油厂催化装置中压蒸汽管线的保温材料。检测结果表明,再用陶瓷纳米纤维隔热保温制品降低了材料生产成本,使用性能稳定,平均散热损失优于相应企业标准(116.8 W/m^(2)),完全满足企业现场隔热保温要求。 展开更多
关键词 废旧硅酸铝 保温隔热 再利用
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即食脆肠中主要残留菌的鉴定及联合调控
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作者 郑瑞生 袁思慧 +3 位作者 黄依林 李佳霓 韩淑贤 苏昆轮 《食品与机械》 CSCD 北大核心 2024年第9期116-122,共7页
[目的]探究脆肠中的主要残留细菌,并进行有效控制。[方法]利用16S rDNA技术鉴定脆肠中的主要残留菌,通过高温筛选出耐热性强的优势腐败菌进行复合抗菌试验。[结果]原辅料、脆肠成品、腐败样品等5组样品中共分离出47株残留菌,隶属8个属,... [目的]探究脆肠中的主要残留细菌,并进行有效控制。[方法]利用16S rDNA技术鉴定脆肠中的主要残留菌,通过高温筛选出耐热性强的优势腐败菌进行复合抗菌试验。[结果]原辅料、脆肠成品、腐败样品等5组样品中共分离出47株残留菌,隶属8个属,分别为芽孢杆菌属(Bacillus)、链球菌属(Streptococcus)、莫拉菌属(Moraxella)、嗜盐碱芽孢杆菌属(Alkalihalobacillus)、库特氏菌属(Kurthia)、乳球菌属(Lactococcus)、肠球菌属(Enterococcus)及漫游球菌属(Vagococcus)。脆肠进行拌料时用的配料酱带有芽孢杆菌,易引入二次污染。经高温灭菌仍残留部分优势腐败菌,与腐败脆肠的主要残留菌同为芽孢杆菌属,其中芽孢杆菌属C7-1和C8-3的耐热性最强;通过添加0.2 g/kgε-聚赖氨酸和0.5 g/kg的柠檬酸能有效抑制两种芽孢杆菌的生长。[结论]即食脆肠产品添加0.2 g/kgε-聚赖氨酸和0.5 g/kg的柠檬酸并结合110℃高温杀菌10 min,(36±2)℃保藏30 d未出现腐败胀袋现象。 展开更多
关键词 即食脆肠 残留菌 16S rDNA 耐热性试验 复合防腐剂
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基于水蓄热的热源厂蒸汽调峰技术
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作者 何海军 《区域供热》 2024年第3期37-41,49,共6页
基于工业供汽负荷波动大、昼夜偏差显著的现状,将水蓄热技术与热源厂热力生产工艺相结合,提出采用蒸汽-除盐冷水的间接换热技术、环氧富锌漆防腐技术和硬质聚氨酯发泡保温技术,并对形状、容积和高径比等罐体结构优化设计,旨在开发一种... 基于工业供汽负荷波动大、昼夜偏差显著的现状,将水蓄热技术与热源厂热力生产工艺相结合,提出采用蒸汽-除盐冷水的间接换热技术、环氧富锌漆防腐技术和硬质聚氨酯发泡保温技术,并对形状、容积和高径比等罐体结构优化设计,旨在开发一种适用于工业供热的蒸汽调峰技术。实践应用表明,基于水蓄热的热源厂蒸汽调峰技术具有稳定高效、简单易操和投资收益显著等优点。本技术还可应用于燃煤机组实现深度调峰、消纳新能源发电等场景,具有重要的现实意义。 展开更多
关键词 工业供热 锅炉 蒸汽调峰 水蓄热 防腐 保温
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夏热冬冷地区办公建筑节能改造设计研究
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作者 蒋峰 《科学技术创新》 2024年第17期173-176,共4页
本文主要探究了夏热冬冷地区某办公建筑的节能改造设计方案。调查发现,该办公建筑一天之中8-18时能耗较高;一年之中夏季能耗最高,冬季次之;空调能耗在总能耗中的占比最大。基于实用性和经济性原则,选择建筑围护结构进行了节能设计,外墙... 本文主要探究了夏热冬冷地区某办公建筑的节能改造设计方案。调查发现,该办公建筑一天之中8-18时能耗较高;一年之中夏季能耗最高,冬季次之;空调能耗在总能耗中的占比最大。基于实用性和经济性原则,选择建筑围护结构进行了节能设计,外墙方面使用EPS保温板,屋顶设计成种植屋面,外窗改造成真空玻璃窗和双层玻璃幕墙。结果表明,相比于原建筑,使用节能设计方案后外墙、屋顶和外窗的传热系数均有大幅度的降低,使得建筑保温隔热性能明显提升,达到了节能降耗的效果。 展开更多
关键词 办公建筑 外墙节能 屋面节能 传热系数
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基于ERAS理念的麻醉苏醒期管理联合术中主动保温干预应用于老年股骨粗隆间骨折病人的效果
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作者 李珊珊 顾雪静 王品 《全科护理》 2024年第19期3665-3668,共4页
目的:探讨基于快速康复外科(ERAS)理念的麻醉苏醒期管理联合术中主动保温干预应用于老年股骨粗隆间骨折病人的效果。方法:将医院2020年11月—2022年11月136例老年股骨粗隆间骨折病人纳入研究,采用随机数字表法分为对照组(n=68)和观察组(... 目的:探讨基于快速康复外科(ERAS)理念的麻醉苏醒期管理联合术中主动保温干预应用于老年股骨粗隆间骨折病人的效果。方法:将医院2020年11月—2022年11月136例老年股骨粗隆间骨折病人纳入研究,采用随机数字表法分为对照组(n=68)和观察组(n=68)。两组均给予术中主动保温,对照组给予常规麻醉苏醒期管理,观察组给予基于ERAS理念的麻醉苏醒期管理,观察两组术后恢复情况、应激反应、恢复质量以及术后并发症。结果:观察组术后气管拔除时间、定向力恢复时间、苏醒室停留时间、住院治疗时间均短于对照组(P<0.05);术后24 h,观察组去甲肾上腺素(NE)、肾上腺素(AD)水平低于对照组(P<0.05);观察组40项恢复质量评分量表(QoR-40)评分较对照组高(P<0.05);观察组并发症发生率低于对照组(P<0.05)。结论:以ERAS理念为基础的麻醉苏醒期管理联合术中主动保温能够有效改善老年股骨粗隆间骨折病人的术后恢复情况,降低应激反应,提高恢复质量,且能减少术后并发症的发生。 展开更多
关键词 股骨粗隆间骨折 主动保温 麻醉苏醒期管理 快速康复外科
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纤维素复合气凝胶的制备及保温隔热性能研究 被引量:1
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作者 巩玲 安昕煜 +3 位作者 孔苗苗 刘畅 李旭 刘志明 《功能材料》 CAS CSCD 北大核心 2024年第1期1092-1097,共6页
利用化学交联和冷冻干燥技术制备了绿色环保的羧甲基纤维素钠(CMC)/明胶(GL)-戊二醛(GA)复合气凝胶(CL-A);研究不同比例的羧甲基纤维素钠(CMC)、明胶(GL)和不同含量的戊二醛(GA)对气凝胶微观结构、热稳定性、力学强度以及保温隔热等性... 利用化学交联和冷冻干燥技术制备了绿色环保的羧甲基纤维素钠(CMC)/明胶(GL)-戊二醛(GA)复合气凝胶(CL-A);研究不同比例的羧甲基纤维素钠(CMC)、明胶(GL)和不同含量的戊二醛(GA)对气凝胶微观结构、热稳定性、力学强度以及保温隔热等性能的影响。实验结果表明,羧甲基纤维素钠(CMC)与明胶(GL)比例为1:2且戊二醛(GA)添加量为15%时的复合气凝胶(C1L2-A15)的压缩强度高达3.03 MPa,较纯羧甲基纤维素钠(CMC)气凝胶增长了7倍左右;热导率低至0.022 W/(m·k),保温效果较好;多孔的三维网络更加致密,改善了复合气凝胶的形貌结构;复合气凝胶的残炭量高达37%,一定程度上提高了热稳定性。 展开更多
关键词 生物质气凝胶 羧甲基纤维素 明胶 压缩性能 保温隔热
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热辐射特征参数对快堆锥形顶盖空间换热特性影响的研究 被引量:1
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作者 冯佳琪 陆道纲 +1 位作者 张钰浩 于宗玉 《核科学与工程》 CAS CSCD 北大核心 2024年第1期55-62,共8页
池式钠冷快堆的钠池内充满高温液态钠,其上方覆盖有氩气,高温液态钠主要通过辐射换热及对流换热的方式向快堆主容器上部结构及氩气空间传递热量,其换热特性及其影响因素十分复杂。辐射发射率及液态钠蒸发形成的气溶胶层对主容器上部结... 池式钠冷快堆的钠池内充满高温液态钠,其上方覆盖有氩气,高温液态钠主要通过辐射换热及对流换热的方式向快堆主容器上部结构及氩气空间传递热量,其换热特性及其影响因素十分复杂。辐射发射率及液态钠蒸发形成的气溶胶层对主容器上部结构的热工水力特性会造成一定影响。因此,为保证主容器上部结构在不同温度载荷下的安全性与稳定性,十分必要获取不同辐射发射率及不同气溶胶层分布下的温度分布。本研究建立大型池式钠冷快堆主容器上部锥形顶盖空间(以下简称“锥顶盖”)数值计算模型,开展数值模拟计算,得到不同发射率及气溶胶层厚度影响下锥顶盖的温度场。研究结果表明,发射率越高,锥顶盖斜肩及氩气空间温度越高;当气溶胶层存在于靠近钠液面的高度范围时(0~0.2 m),增加其厚度可使氩气空间局部温度升高,但对锥顶盖斜肩温度影响有限。发射率增高53%,则辐射换热量增加31.47%,格拉晓夫数(Gr)减少19.29%,辐射换热效果增强,自然对流效果减弱;气溶胶层高度由0增加到0~0.1 m时,对辐射换热量的吸收增加22.68%,格拉晓夫数(Gr)减少19.29%,气溶胶层高度由0~0.1 m增加到0~0.2 m时,透过气溶胶层的辐射换热量减少了0.04%,格拉晓夫数(Gr)增加了0.9%,辐射换热效果减弱,自然对流效果加强。 展开更多
关键词 快堆锥形顶盖空间 辐射换热 自然对流 发射率 吸收系数
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基于模糊控制的高温热泵果脯干燥系统设计 被引量:1
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作者 孙乐平 郭小璇 +1 位作者 韩帅 郭敏 《节能》 2024年第5期98-102,共5页
针对高温热泵干燥技术替代传统蒸汽或热风干燥在果脯烘干中的应用场景,研制高温热泵干燥系统。结合热交换器结构与换热特性,分析果脯干燥工艺特点,将模糊逻辑控制应用于热泵干燥过程;考虑干燥箱的热场分布、温度梯度控制与干燥时间的耦... 针对高温热泵干燥技术替代传统蒸汽或热风干燥在果脯烘干中的应用场景,研制高温热泵干燥系统。结合热交换器结构与换热特性,分析果脯干燥工艺特点,将模糊逻辑控制应用于热泵干燥过程;考虑干燥箱的热场分布、温度梯度控制与干燥时间的耦合,对模糊控制器、模糊规则表进行详细设计,采用可编程逻辑控制器(PLC)控制的热泵干燥控制系统进行龙眼干燥实验测试。结果表明,模糊控制具有良好的稳态和瞬态性能,具有温度调节快、误差小、干燥效率高、节能效果好等优势,适用于干燥工艺复杂、温度调节要求高、减少人为干预影响品质的果蔬类农产品深加工。 展开更多
关键词 高温热泵 果脯干燥 温度控制 模糊控制
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兼顾高/低温环境性能的动力电池热管理系统设计
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作者 刘松燕 王卫良 +1 位作者 彭世亮 吕俊复 《储能科学与技术》 CAS CSCD 北大核心 2024年第7期2181-2191,共11页
热特性对电动汽车的性能有着重要的影响。低温环境严重影响锂电池的容量和寿命,而高温环境则可能导致热失控。为了保证锂电池在高低温环境下的安全高效运行,本研究提出一种兼顾高低温的热管理系统,通过保温材料和相变材料组合成的蓄热... 热特性对电动汽车的性能有着重要的影响。低温环境严重影响锂电池的容量和寿命,而高温环境则可能导致热失控。为了保证锂电池在高低温环境下的安全高效运行,本研究提出一种兼顾高低温的热管理系统,通过保温材料和相变材料组合成的蓄热模块的灵活拆卸,实现对高低温天气下电池的散热和保温。使用Star CCM+软件进行建模和仿真。研究结果表明:动力电池在不同倍率放电后静置维持在0℃以上的时间最高达17 h,低温下静置与无热管理的情况下相比保温时长增加了约8倍,比单纯使用相变材料保温时长增加了近3倍,且验证了添加隔热层的必要性。在实际应用中表明停车后可直接启动,避免电动汽车频繁的预加热。在高温条件下拆掉蓄热模块使用风冷散热既节省了能源又进一步加强了该系统散热能力。以1C~3C倍率放电后,与未添加散热措施的电池组对比,添加热管理散热系统后电池组最高温度分别降低了34%、42%和48%,添加翅片后对电池的降温效果有明显作用,1C~3C放电倍率下最高温度比未添加翅片的电池组最高温度分别降低4.8%、5.4%、6.7%,放电倍率越高添加翅片的散热效果越明显。 展开更多
关键词 电动汽车 电池热管理 相变材料 热管 保温
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相温子库传热优化及柠檬贮藏效果
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作者 马笑巍 王晓冉 +6 位作者 王晓东 刘岳 梁富浩 赵薇 李喜宏 姜瑜倩 李学进 《食品研究与开发》 CAS 2024年第2期132-137,共6页
为研究子库传热面积、材料、对流风速和厚度对子库传热的影响,以及优化子库传热对柠檬保鲜效果的影响。通过增大子库传热面积、提高对流风速等方法,确定子库传热的主要影响因素,并对其进行优化试验和对柠檬进行贮藏效果研究。结果表明:... 为研究子库传热面积、材料、对流风速和厚度对子库传热的影响,以及优化子库传热对柠檬保鲜效果的影响。通过增大子库传热面积、提高对流风速等方法,确定子库传热的主要影响因素,并对其进行优化试验和对柠檬进行贮藏效果研究。结果表明:子库传热面积对子库传热影响最为显著,其次为子库对流风速;柠檬贮藏效果研究结果表明,相温贮藏相较于普通冷藏能明显抑制柠檬果皮变黄和失重现象,并减缓维生素C、总可溶性固形物等营养物质的流失,优化子库传热后能进一步提升相温贮藏效果。 展开更多
关键词 相温库 精准控温 子库传热 传热优化 相温贮藏 柠檬保鲜
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