氢夹点技术方法研究进展和评价

氢夹点技术作为氢气网络优化的重要方法,以其简单直观、高效易懂等优点,自20世纪90年代末被提出至今,在解决氢网络用氢瓶颈上,已经有了成熟稳健的发展。本文介绍了氢夹点技术的基本原理,综述并分析了剩余氢量图解法、严格氢夹点图解法、氢负荷-流量图法、源组合曲线法、多杂质赤字率图解法等多种氢夹点技术方法的提出及研究进展,并对这些方法进行比较和评价,得到各种方法的优缺点和应用范围。最后指出多约束条件下的氢夹点技术方法研究、建立动力学建模以及炼厂氢网络柔性优化设计等将成为未来几年氢夹点技术的研究热点。     

氢燃料电池用于发电技术的研究现状

综述了氢燃料电池的发电技术背景,论述了氢燃料电池中氢气的来源有煤制氢、天然气制氢、工业副产氢和电解水制氢,并调研了目前氢燃料电池的应用方向,从技术水平、安全运营及绿色环保等角度,分析了国内外氢燃料电池发电技术的优势特征和应用现状。最后从电池性能、生产成本和能源利用率等方面对氢燃料电池发电技术的发展作出展望。     

船用燃料电池技术的现状和发展

氢燃料动力船舶具有高效、无污染、设备运行噪音低等优势,是实现船舶“零排放”目标的主要技术路线之一。本文介绍了船用氢燃料电池技术现状、问题及技术需求。并对船用燃料电池技术、船用储氢技术、船用氢能相关标准与法规规范、船用氢燃料动力系统与应用以及等方面的进展进行了阐述。最后提出了我国船用氢燃料电池技术发展对策与建议。     

光合细菌生物制氢

阐述了固氮酶催化的光合放氢和氢酶催化的黑暗厌氧产氢机制,描述了光合细菌原初反应的微观反应动力学以及电子定向转移和质子转位耦联驱动的三磷酸腺苷合成机制与固氮产氢过程。讨论了影响光合放氢的主要因素,如光、氧气、菌株特性、氢供体和氮源等。介绍了固定化、混合培养和重复分批培养等实用化技术和遗传工程技术在光合细菌产氢研究中的应用现状,并就存在的问题进行了讨论。最后对光合制氢技术的发展趋势和应用前景进行了评述。     

氢技术：研究,开发及工业应用展望

本文简要介绍了氢技术的发展状况,就氢的生产、运输及应用等问题作了详细的讨论,并给出了与氢技术有关的研究和发展方案。     

日本焦炉煤气制氢技术

焦炉煤气因能提供燃料电池汽车所用的氢而受到关注,充分运用钢铁厂副产氢的非现场集中制氢方式可有效降低制氢成本.新日铁公司在参与日本"氢/燃料电池开发"、"钢铁厂副产煤气制氢技术"等研发项目中,积累了包括制氢、输氢、充氢在内的供氢技术.以下是日本焦炉煤气制氢技术的现状及将来大规模供氢所面临的问题与应对措施.     

掺氢天然气管道输送研究进展和挑战

风电、光电的波动性是其发展的重要制约因素之一。国际上普遍认为,可再生能源制氢结合在役天然气管网掺氢输送的技术是解决大规模风光电消纳问题的有效途径之一。本文介绍了掺氢天然气管道输送应用示范项目,综述了管材氢相容性、设备掺氢适应性、管道运行安全保障以及标准体系建设4个方面的研究进展,并指出了目前发展掺氢天然气管道输送面临的问题与挑战。结合我国掺氢天然气管道输送发展现状,本文建议统筹规划掺氢天然气管道输送网络,因地制宜有序推进掺氢天然气基础设施建设,加强管材氢相容性、管网设备和部件掺氢适应性以及管道运行安全保障技术研究,逐步开展掺氢天然气输送技术应用示范,加快制定掺氢天然气管道输送规范标准,促进氢能产业发展。     

重油临氢/供氢热裂化技术中国专利总览

借助专利信息服务平台的分析工具,从申请趋势、来源国分布、技术布局、申请人、专利功效矩阵等角度分析了重油临氢/供氢热裂化技术的相关专利文献。分析结果表明,临氢/供氢热裂化技术已进入了衰退期,专利技术大部分集中在中国石化、中国石油和部分国内私企手中,而国外大公司在中国的专利布局意识不强烈;目前研究开发的重点是临氢/供氢热裂化与其他炼油工艺的组合工艺技术以及催化剂体系的改进技术,中国石化在该领域布局早、申请量大、综合实力较强。     

生物制氢研究进展(Ⅰ)产氢机理与研究动态

阐述了7类生物制氢系统的产氢机理、影响因素以及提高产氢率和产氢量的方法,介绍了国外最新的研究进展。光发酵生物制氢技术和厌氧发酵生物制氢技术是研究的热点,而厌氧发酵由于产氢效率较高而成为最具潜力的生物制氢技术之一。光合-发酵杂交技术不仅减少了所需光能,而且增加了氢气产量,同时也彻底降解了有机物,使该技术成为生物制氢技术的发展方向。     

固定化细胞技术发酵产氢的应用研究

微生物发酵产氢的固定化细胞技术与其非固定化细胞技术相比,前者具有很大的优越性,能显著提高发酵系统的产氢量。对微生物发酵产氢固定化细胞的制备方法及其应用载体进行了介绍,分析了国内外固定化细胞技术在厌氧产氢中的最新进展,指出了固定化细胞技术发酵产氢存在的问题,并对其发展进行了探讨。     

High internal phase emulsion foams: Copolymers and interpenetrating polymer networks

High internal phase emulsion (HIPE) copolymer and interpenetrating network foams were prepared from 2‐ethylhexyl acrylate (EHA), styrene (S) and divinylbenzene (DVB) using a unique process. The morphologies, thermal properties and dynamic and static mechanical properties of these foams were investigated. The glass transition temperatures and damping properties of the EHA/S copolymer foams vary with its composition. IPN foams with very broad tan 5 peaks were obtained. The damping properties of IPN foams were tailored through changing copolymer composition and monomer composition. The IPN foams based on a copolymer foam and styrene had a broader tan δ peak, a higher glass transition temperature and a higher modulus than tne copolymer foams of similar overall styrene contents. It is therefore possible to prepare novel damping foams based on polyHIPE foams through the synthesis of interpenetrating polymer networks.     

Processing and characterization of syntactic carbon foams containing hollow carbon microspheres

The effects of heat-treatment on the properties of carbon foams were studied. The carbon foam was first prepared by adding hollow carbon microspheres to phenolic resin, followed by post-curing, pre-carbonization and carbonization. The mechanisms of failure behaviour and the increase of electrical and thermal conductivities showed that the properties of the foams were influenced by the heat-treatment temperature. Results showed that the introduction of more interval voids during carbonization resulting in a reduction of the mechanical properties. Carbon foams with electrical conductivity of 1.20 S/cm and thermal conductivity of 12.85 W/mK were obtained.     

Hydrophilic foams containing corn products for horticultural use

Polyurethane foams containing equal amounts of commercial unmodified cornstarch and a polyisocyanate-terminated polyether exhibit properties suitable for horticultural applications. The use of cornstarch in the foam formulation increased the volume by one-fourth as compared to the foam without cornstarch. This volume increase represents an economic advantage of 20% savings based on material cost. When cornstarch or corn flour is added to the foam formulation, the foams are more resistant to compressive force. Upon wetting and draining, the foams prepared with no auxiliary blowing agent and containing corn products exhibit higher volumes than do the unfilled foams. Radish seeds planted inside 25 mm cubes of foams began to sprout after 1 day. Early developmental growth for the plants was similar in the control and cornstarch-filled foams. Spectroscopic analyses of the starch-containing foams revealed that 60–70% of the cornstarch was metabolized within 4–5 weeks by a microbial consortium. Control polyurethane foams were not affected by the microorganisms tested. © 1994 John Wiley & Sons, Inc.

1 This article is a U.S. Government work and, as such, is in the public domain in the United States of America.

     

Solvent-blown,rigid urethane foams from low cost castor oil-polyol mixtures

The preparation of solvent-blown rigid urethane foams from low cost castor oil-polyol mixtures was investigated. Solutions of triisopropanolamine, and of mixtures of triisopropanolamine and triethanolamine in castor oil, were used as the polyol component of these foams. Foams were prepared by reacting these polyol mixtures, in the presence of catalyst, surfactant, and trichlorofluoromethane, with prepolymers prepared from toluenediisocyanate and certain polyether polyols or mixtures of these polyether polyols with castor oil. The effect of polyol and prepolymer composition and blowing agent concentration on such foam properties as density and compressive strength was investigated. The properties of the castor oil-based foams were comparable to those of foams obtained from more costly polyols. Presented at the Spring Meeting of the American Oil Chemists' Society, St. Louis, Missouri, May 1–3, 1961. A laboratory of the Western Utilization Researchand Development Division, Agricultural Research Service, U. S. Department of Agriculture.     

Preparation of semirigid polyurethane foam with liquefied bamboo residues

Bamboo residues were liquefied by using a solvent mixture consisting of polyethylene glycol 400 and crude glycerol (4/1, w/w) with 98% sulfuric acid as catalyst at 160°C for 120 min. The liquefied bamboo had hydroxyl values from 178 to 200 mg KOH/g and viscosities from 507 to 2201 mPa S. The obtained bamboo‐based polyols were reacted with various amounts of polyaryl polymethylene isocyanate (PAPI), using distilled water as blowing agent, silicone as surfactant, and triethylenediamine and dibutyltine dilaurate as cocatalyst to produce semirigid polyurethane (PU) foams. The [NCO]/[OH] ratio was found to be an important factor to control the mechanical properties of PU foams. At a fixed [NCO]/[OH] ratio, both density and compressive strength of PU foams decreased with the increase of bamboo content. The microstructure of PU foams indicates that [NCO]/[OH] ratios are important for cell formation and chemical reactions. The uniformity and cell structure of the foams are comparable to their corresponding compressive strengths. Moreover, the thermogravimetry analysis showed that all the semirigid PU foams had approximately the same degradation temperature of about 250 to 440°C. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Poly(methyl methacrylate) hybrid syntactic foams with hollow glass microspheres and polyhedral oligomeric silsesquioxanes

The study aims to produce poly(methyl methacrylate) (PMMA)-based lower density syntactic foams with hollow glass microspheres (HGMs) and to improve their mechanical properties by the addition of polyhedral oligomeric silsesquioxanes (POSSs) while maintaining the thermal properties of the neat polymer. First to understand the effect of POSS addition, PMMA–POSS composites with octaisobutyl and octaphenyl POSS were produced through extrusion. Higher relative flexural and impact strengths were obtained with POSS addition to PMMA. Obtaining more enhanced properties with octaphenyl POSS, PMMA-HGM-POSS hybrid syntactic foams were prepared with this additive. In general, the specific flexural strength and modulus of the PMMA syntactic foams were improved with the POSS loading, while the lower density and thermal properties of the PMMA syntactic foams were maintained. PMMA hybrid syntactic foams with 15 wt % HGMs and 0.25 wt % POSS exhibited 37.6% improvement in the specific flexural modulus with respect to the neat PMMA. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48368.     

Preparation and properties of multi-walled carbon nanotube/carbon/polystyrene composites

Multi-walled carbon nanotube (MWCNT)/C/polystyrene (PS) composite materials were prepared by in situ polymerization of monomer in preformed MWCNT/C foams. MWCNT/C foams were preformed using polyurethane foam as template. The preformed MWCNT/C foams had a more continuous conductive structure than the carbon nanotube networks formed by free assembly in composites. The structure of the MWCNT/C foam network was characterized with scanning electron microscopy. The MWCNT/C/PS composites have an electric conductivity higher than 0.01 S/cm for a filler loading of 1 wt.%. Enhancement of thermal conductivity and mechanical properties by the preformed MWCNT/C foam were also observed.     

Rigid urethane foams from blown castor oils

Solvent-blown rigid urethane foams prepared from a low-cost polyol mixture composed of raw castor oil and triisopropanolamine have been described. Foams with higher compressive strengths can be obtained by substituting oxidized (blown) castor oil for the raw castor oil in formulations of this type. The properties of rigid foams prepared from several commercial blown castor oils are described. The properties of these foams are correlated with the degree of oxidation of the blown oils used, as indicated by their oxygen content, density, viscosity, and refractive index. Removal of acid from blown oils having high acid values has no significant effect on the compressive strength of foams prepared from these oils. When blown castor oil is used instead of raw castor oil, less isocyanate is required to produce a urethane foam of specified density and compressive strength. Presented at the AOCS meeting in Toronto, Canada, 1962. A laboratory of the W. Utiliz. Res. & Dev. Div., ARS, U.S.D.A.     

Conductive elastomeric foams prepared by in situ vapor phase polymerization of pyrrole and copolymerization of pyrrole and N-methylpyrrole

Electrically conductive elastomer foams were prepared by in situ vapor phase copolymerization of pyrrole and N-methylpyrrole within preformed polyurethane foams. The conductive polymer is formed within the dense polymer phase of the foam, and the conductivity of the composite foam ranged from 10^?1 to 10^?7 S/cm. The conductvity depended on the density of the foam, the amount of conducting polymer incorporated, and the copolymer composition. Replacing with N-methylpyrrole in the copolymer lowered the conductivity.     

Solvent-blown rigid urethane foams from castor-based polyols

The preparation of trichlorofluoromethane-blown rigid urethane foams using toluenediisocyanate and castor oil-derived polyols was investigated. The castor-based polyols included castor oil, hydroxylated castor oil, technical glycerol-, penta-erythritol-, and sorbitol monoricinoleates, and N,N-bis(2-hydroxyethyl) ricinoleamide. The last of these yielded the best foams when used as the sole polyol component added to the prepolymer. However better foams were obtained by using, as the polyol component, a mixture of a castor oil-derived polyol and a lower-molecular-weight polyol with a higher hydroxyl content. These polyol mixtures yielded more highly cross-linked polymers and hence foams with higher compressive strengths and less tendency to shrink after foaming. The effect of catalyst, silicone surfactant, and trichlorofluoromethane content was also investigated. An empirical relationship between density and compressive strength in a given foam system was derived. Presented at the fall meeting, American Oil Chemists' Society, New York, October 17–19, 1960. A laboratory of the Western Utilization Research and Development Division. Agricultural Research Service, U.S. Department of Agriculture.