首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 812 毫秒
1.
高森  赵兆瑞  陈曦 《广州化学》2021,46(2):16-24,44
总结了多种全无霜空气源热泵的系统原理和实现无霜化的吸附式除湿技术.介绍了液体吸附式和固体吸附式全无霜空气源热泵系统,并比较其优缺点,前者具有大量处理湿空气的优点,后者具有能效比高等优点.对吸附式除湿的吸附材料和吸附装置进行综述,介绍了能低温再生和吸附量较大的吸附材料.最后指出,吸附材料和除湿装置需要进一步研究从而提高除...  相似文献   

2.
吸附式空调系统的原理及添加剂强化吸附工质性能的研究   总被引:7,自引:0,他引:7  
氯化锂晶体具有很高的吸水性能,在吸附式空调制冷系统中常常被用作吸附剂。本文介绍了吸附式空调制冷系统的原理,研究了吸附剂(氯化锂)、吸附质(水汽)的性质;采用高真空吸附重量法测定氯化锂的等温吸附曲线及氯化锂吸附水汽的速率,并通过添加一种既有吸附增稠作用,又能强化氯化锂吸附性能的添加剂,改善氯化锂的等温吸附特性,降低氯化锂的再生温度。采用氯化锂混合吸附剂-水的开式旋转吸附式空调系统,具有显著的节能效果和双重杀菌功能,提供人们所喜爱的舒适空调域(室内温湿度26.7℃/50%RH),同时改善室内空气品质。  相似文献   

3.
水稳定性金属有机框架材料的水吸附性质与应用   总被引:2,自引:0,他引:2  
金属有机框架材料(metal-organic frameworks,MOFs)因具有高比表面积、高孔隙率以及可调的孔结构及孔内环境,在气体吸附、分离以及催化等方面展现出巨大应用潜力.由于水蒸气广泛存在于空气和各类工业气体中,深入理解MOFs与水蒸气之间相互作用机制,并开发具备高水稳定性以及水蒸气吸附与脱附行为可调的MOFs,不仅具有显著的科学意义,而且对推动MOFs的实际应用具有重要的现实意义.本综述将围绕以下内容展开论述:高水稳定性MOFs的设计规律;MOFs对水蒸气的吸附/脱附行为;吸水MOFs在工业气体干燥、沙漠取水、吸附式热泵以及室内湿度调节等领域的应用.  相似文献   

4.
《分析试验室》2021,40(4):390-393
结合非固体接触式的全蒸发技术(FET)与顶空气相色谱-质谱联用(HS-GC-MS)技术构建了一种可用于不规则材料的体积分析方法。以苯乙烯和异丙苯为目标分析物,利用气相分子平衡浓度与质谱信号响应值这两个变量之间的线性关系,实现了对多种不规则材料体积的准确测定及其吸附性能分析。实验结果表明:对于以搅拌子为代表的非吸附型材料,全蒸发顶空气相色谱-质谱(FEHS-GC-MS)的响应值不受平衡温度影响,可在不同温度条件下准确计算出其体积;石蜡和石墨烯气凝胶等吸附型不规则材料,可先通过绘制平衡温度-蒸发目标分子吸附曲线研究其吸附性能,然后选取适宜的全脱附温度用于测算其真实体积。该研究为不规则材料的体积测算及其吸附性能研究提供了一种分析策略,可用于新型多孔吸附材料和固相微萃取涂层材料等研究领域。  相似文献   

5.
恒电流动态库仑法检测空气中偏二甲肼   总被引:1,自引:0,他引:1  
许国根  李瑛 《分析化学》1999,27(3):368-368
偏二甲肼[(CH_3)_2NNH_2](UDMH)是液体火箭的主要推进剂,具有中等偏高毒性,极易挥发.空气中最大允许浓度为0.5ml/m~3.因此,研制检测空气中微量UDMH的装置.对于预防其中毒,具有十分重要的意义.空气中UDMH的测定方法主要有:固体吸附/分光光度法;固体吸附/气相色谱法.这两种方法均有测量范围大、下限低、测量准确等优点,但操作复杂、仪器条件要求高,且不能连续测定.本文采用库仑滴定法测定空气中的UDMH,依据法拉第电解定律,研究空气中UDMH与库仑池中电解液进行电化学反应,测量其在反应过程中产生的电流值,得到空气中UDMH浓度与响应电流的关系,从而求出UDMH气体的浓度.  相似文献   

6.
分子筛材料在小分子吸附分离中的应用   总被引:1,自引:0,他引:1  
吸附分离技术与工艺在工业上具有重要意义. 常见的吸附剂包括沸石分子筛、 金属有机框架材料、 活性炭等材料. 分子筛具有比表面积大、 稳定性高、 生产成本低等优势, 可以满足吸附分离技术中高效、 节能和环保的需求, 是一种非常有应用前景的小分子混合物分离吸附剂. 本文综合评述了吸附分离领域中常用的吸附剂材料的特点和吸附分离机理与评价方法, 总结了分子筛在空气分离、 烃类分离、 二氧化碳吸附、 芳香硫化物脱除、 一氧化碳吸附、 氮氧化物吸附、 氢气储存吸附及氢同位素分离等领域的应用, 并对基于分子筛膜的小分子混合物分离现状进行了介绍. 此外, 本文还系统分析了分子筛对不同混合物的吸附分离性能与其拓扑结构、 骨架组成及改性方法之间的关系, 并对未来的研究前景进行了展望.  相似文献   

7.
压电晶体吸附检测器及其在环境分析中的应用   总被引:1,自引:0,他引:1  
石英压电晶体吸附检测器是监测空气中痕量无机或有机污染物的有效工具,因为具有灵敏度高、选择性好、装置简单等优点,既可作静态取样分析,又可作动态连续测定,因而受到各国科学家的重视,近年来有很大发展,取得了不  相似文献   

8.
氮化硼纳米片具有高机械强度、良好的化学惰性和热稳定性等优点.除了这些性质,基于纳米氮化硼的凝胶材料还有高比表面积、大孔隙率等特点.因此它在催化、储氢、除污和气体吸附等领域具有潜在的应用前景.这篇综述主要介绍了氮化硼纳米片及其凝胶材料的制备,举例说明了氮化硼凝胶的关键应用并加以展望.  相似文献   

9.
水污染问题目前已成为世界上最为紧迫的环境问题之一.全氟烷基和多氟烷基物质(PFASs)因其具有高毒性、持久性、生物积累性、远距离迁移性等性质,对人类健康和生态环境产生了严重的危害.开发PFASs的检测和去除技术成为了当今社会的关注重点.超分子大环材料作为一类新兴的多功能材料,具有丰富的主客体分子识别、良好的环境适应性和结构的可设计性等优点.超分子大环材料的可设计性赋予其特定的多功能性,使其成为同时检测和去除环境水中PFASs的理想平台.本文综述了超分子大环及其衍生物在检测和吸附去除PFASs中的应用,首先对常见的PFASs分类进行了介绍,接下来探讨了具有PFASs高吸附效率的特定超分子结构类别及相关吸附机理.最后介绍了超分子吸附剂再生的方法.同时也为具有改进PFASs去除性能的下一代功能超分子材料的设计提供了一些见解.  相似文献   

10.
辐射接枝技术已成为高分子材料改性的重要方法之一.和传统化学接枝方法相比,辐射接枝技术具有操作简单,易于控制,不限制基材和单体等优点,近年来已被广泛应用于吸附材料的制备.采用辐射接枝技术制备的吸附材料,其功能团主要分布在基材表面,具有单体用量少,成本低,吸附脱附速度快,功能团利用率高,选择性好的特点.本文综述了近年来辐射接枝技术在制备选择性吸附材料方面的最新研究进展,包括对重金属、放射性核素、半金属、非金属、稀土元素、贵金属和染料等不同污染物吸附材料的合成及其应用,并对辐射接枝技术在制备吸附材料中的研究方向进行了展望.  相似文献   

11.
A. Hauer 《Adsorption》2007,13(3-4):399-405
The evaluation of solid adsorbents in open sorption systems for heating, cooling and thermal energy storage (TES) applications is crucial for the ecological and economical performance of these systems. An appropriate adsorbent has to reach the temperature limit given by the heating/cooling system of the consumer. It has to provide high energy efficiency and a high energy density for storage applications. A method for an easy evaluation of different adsorbents for a specific application has been developed. The method is based on the adsorption equilibrium of the adsorbent and water vapor. The crucial property for the discussed field of applications is the differential heat of adsorption. Criteria for the evaluation of the adsorbent are the breakthrough curves (responsible for the dynamics of the process), the possible temperature lift (or the dehumidification) of the air, the thermal COP and the storage capacity.  相似文献   

12.
刘振  陈曦  郑朴  纪煜哲 《广州化学》2021,46(1):64-71
为了优化热泵系统效率,主要采用编程计算,对以R32、R290以及R410A为工质的两级压缩热泵系统进行性能研究,对比了系统的蒸发温度、冷凝温度、中间温度和混合温度等对COPh的影响。研究发现不完全冷却系统COPh比完全冷却系统更高,在不同工况下存在不同的最佳中间温度,使得COPh有最大值,R290和R410A的混合温度变化对系统COPh影响较大。  相似文献   

13.
Thermoelectric materials represent a new paradigm for harvesting low-grade heat, which would otherwise be dissipated to the environment uselessly. Relative to conventional thermoelectric materials generally composed of semiconductors or semi-metals, ionic thermoelectric materials are rising as an alternative choice which exhibit higher Seebeck coefficient and lower thermal conductivity. The ionic thermoelectric materials own a completely different thermoelectric conversion mechanism, in which the ions do not enter the electrode but rearrange on the electrode surface to generate a voltage difference between the hot and cold electrodes. This unique character has inspired worldwide interests on the design of ionic-type thermoelectric converters with attractive advantages of high flexibility, low cost, limited environmental pollution, and self-healing capability. Referring to the categories of ionic thermoelectric conversion, some representative ionic thermoelectric materials with their respective characteristics are summarized in this minireview. In addition, examples of applying ionic thermoelectric materials in supercapacitors, wearable devices, and fire warning system are also discussed. Insight into the challenges for the further development of ionic thermoelectric materials is finally provided.  相似文献   

14.
廖颖敏  黄晓佳  王卓卓  甘蕊 《色谱》2021,39(4):368-375
食品中残留的痕量有毒物质严重威胁人体健康,对其进行分析十分必要。然而,食品中有毒物质种类多、量少、基质复杂,需选择适当的样品预处理技术进行提取和净化。磁固相萃取(MSPE)因具有操作简单、省时快速、无需离心过滤、环境友好等优点,被认为是一种高效的样品预处理技术并应用于食品分析中。MSPE中使用的磁性吸附剂的吸附容量和选择性是影响MSPE萃取效率和选择性高低的关键,对所建立分析方法的准确度起着关键作用。碳基磁性材料是具有价格低廉、来源丰富、比表面积大、化学稳定性好、吸附容量高、绿色环保等优点的一类新型功能性磁性材料,可以富集不同性质的有机、无机分析物,在环境分析、生物检测、污染治理等多个领域取得了较大进展。近年来,基于碳基磁性材料的MSPE技术在食品分析预处理领域逐渐得到应用,但尚处于起步阶段,存在巨大的应用潜力。该文以碳基类别(碳纳米管、石墨烯、金属有机骨架衍生碳、活性炭等)为主线,综述了采用MSPE技术,以碳基磁性材料为吸附剂,对食品样品中酯类、真菌毒素、多环芳烃、抗生素、生物碱、酚类、维生素、抗菌药等物质进行萃取,进而采用液相色谱法等进行分析的应用实例,同时阐述了该技术存在的问题,并对其发展方向做出了展望。该综述将为基于碳基磁性材料的MSPE技术在食品分析中的广泛应用提供理论依据和技术支撑。  相似文献   

15.
Desiccant driven dehumidification for maintaining the proper humidity levels and atmospheric water capture with minimum energy penalty are important aspects in heat pumps, refrigeration, gas and liquid purifications, gas sensing, and clean water production for improved human health and comfort. Water adsorption by using nanoporous materials has emerged as a viable alternative to energy-intensive industrial processes, thus understanding the significance of their porosity, high surface areas, vast pore volumes, chemical and structural features relative to the water adsorption is quite important. In this review article, important features of nanoporous materials are presented, including zeolites, porous carbons, as well as crystalline and amorphous porous organic polymers (POPs) to define the interactions between the water molecules and the polar/non-polar functional groups on the surface of these nanoporous materials. In particular, focus is placed on the recent developments in POPs in the context of water capture as a result of their remarkable stability towards water and wide range of available synthetic routes and building blocks for their synthesis. We also highlighted recent approaches to increase the water sorption capacity of POPs by modifying their structure, morphology, porosity, and chemical functionality while emphasizing their promising future in this emerging area.  相似文献   

16.
草酸改性空气凤梨生物炭吸附甲醛的机理研究   总被引:1,自引:0,他引:1  
探究草酸改性园林废弃物类生物炭对溶液中甲醛的吸附效率和固定的机理,为园林废弃物类生物炭在甲醛污染控制方面的应用提供科学依据。利用马弗炉在低氧条件下将空气凤梨原材料和草酸改性后的原材料制备成生物炭。然后利用实验室模拟法,研究不同反应时间、甲醛浓度、pH对生物炭吸附效果的影响,并分析草酸改性如何提高园林废弃物类生物炭对甲醛的吸附性能。(1)生物炭对乙酰丙酮和酚试剂两种甲醛检测方法的精度有影响,对乙酰丙酮检测法的影响较小;(2)相比于未改性生物炭,草酸改性通过酸化分解杂质能够使改性生物炭比表面积提高约17倍,孔隙体积增加195.9%;(3)草酸改性后生物炭对甲醛的吸附量为11.6 mg g-1,比未改性生物炭提高了12.95%,并且在60 min时趋于吸附平衡的状态;(4)Boehm滴定法表明草酸改性能够显著提高制备后生物炭上的官能团(羧基51.8%,羰基13.7%和内酯基35.9%),但酚羟基(4.5%)含量增加不明显,而相关性分析证实比表面积、羧基和内酯基官能团的增加是提高生物炭吸附甲醛的主要因素。实验证明,空气凤梨制备成生物炭用于溶液中甲醛的吸附是可行的,并且草酸改性能够进一步通过官能团提高其吸附能力,这为园林废物资源化利用提供了新的思路。  相似文献   

17.
The aim of this study is the development of a new adsorbent for the desiccant material which can be regenerated by the domestic exhaust heat by using natural mesoporous material, Wakkanai siliceous shale. To improve this shale’s performance to adsorb/desorb the water vapor, lithium chloride, calcium chloride or sodium chloride was supported into the mesopores by impregnating with each chloride solution. Especially sodium chloride was effective to increase the water vapor adsorption amount 5–7 times of that of natural shale in the relative humidity range from 50 to 70%. Moreover, the appropriate impregnating concentrations were determined as 5wt% from the relationship between the maximum water vapor adsorption amount and the mesopore volume. Based on these results, a new desiccant filter has been developed by impregnated original paper with lithium chloride and sodium chloride. This paper contained shale powder in the synthetic fibers. The dehumidification performance of this filter was evaluated under the simulated summer condition in Tokyo. From the cyclic adsorption/regeneration test, this shale and chlorides filter could adsorb and desorb 60 g/h water vapor repeatedly at the regeneration temperature of 40°C. On the other hand, a silica gel filter and a zeolite filter adsorbed and desorbed only 10 g/h and 25 g/h, respectively. These results suggested that the shale impregnated with the chlorides has the best dehumidification ability as a new desiccant material. Further, the desiccant filter made from the shale will achieve the effective use of the low temperature exhaust heat.  相似文献   

18.
Epoxy resins are well-known materials that show beneficial properties, such as high tensile strength and modulus, good adhesive properties, low cost, and ease of processing and environmental advantages. However, epoxy resin adhesive has no characteristic of thermal storage. Latent heat storage is one of the favorable kinds of thermal energy storage methods considered for energy saving and thermal efficiency in various fields, such as solar air conditioning systems and buildings. So we prepared thermal-enhanced epoxy resin adhesive by using PCM. This paper addresses the effects of n-hexadecane and sodium lauryl sulfate on the thermal properties and chemical properties of epoxy resin adhesive and HEAC, using differential scanning calorimetry, thermal gravimetric analysis, and Fourier transform-infrared spectroscopy. Also, we evaluated the applicability of composite epoxy resin adhesive to wood-based flooring using n-hexadecane, through measurement of bonding strength from universal testing machine analysis.  相似文献   

19.
作为一种简便高效的样品前处理技术,固相微萃取(SPME)在食品、环境水样和生物体液等复杂基质残留污染物检测中得到广泛应用。为进一步提高净化效率和降低使用成本等,大量文献报道了涂层纤维的制备条件和吸附剂的选择。本文综述了SPME涂层纤维的制备方法、材料及应用。描述了不同材料对于不同分析物的吸附原理,特别讨论了难挥发与热不稳定性分析物的SPME分析步骤,总结了SPME存在的问题及今后发展趋势,为后续SPME技术的开发提供理论依据。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号