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Therapeutic importance of hydrogen sulfide in age-associated neurodegenerative diseases 预览
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作者 Rubaiya Tabassum Na Young Jeong Junyang Jung 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第4期653-662,共10页
Hydrogen sulfide(H2S)is a gasotransmitter that acts as an antioxidant and exhibits a wide variety of cytoprotective and physiological functions in age-associated diseases.One of the major causes of age-related disease... Hydrogen sulfide(H2S)is a gasotransmitter that acts as an antioxidant and exhibits a wide variety of cytoprotective and physiological functions in age-associated diseases.One of the major causes of age-related diseases is oxidative stress.In recent years,the importance of H2S has become clear,although its antioxidant function has not yet been fully explored.The enzymes cystathionineβ-synthase,cystathionineγ-lya-se,and 3-mercaptopyruvate sulfurtransferase are involved in the enzymatic production of H2S.Previously,H2S was considered a neuromodulator,given its role in long-term hippocampal potentiation,but it is now also recognized as an antioxidant in age-related neurodegeneration.Due to aerobic metabolism,the central nervous system is vulnerable to oxidative stress in brain aging,resulting in age-associated degenerative diseases.H2S exerts its antioxidant effect by limiting free radical reactions through the activation of antioxidant enzymes,including superoxide dismutase,catalase,and glutathione peroxidase,which protect against the effects of aging by regulating apoptosis-related genes,including p53,Bax,and Bcl-2.This review explores the implications and mechanisms of H2S as an antioxidant in age-associated neurodegenerative diseases,including Alzheimer’s disease,Parkinson’s disease,Huntington’s disease,and Down syndrome. 展开更多
关键词 3-mercaptopyruvate SULFURTRANSFERASE aging antioxidant cystathionineβ-synthase cystathionineγ-lyase GLUTATHIONE hydrogen sulfide NEURODEGENERATIVE disease oxidative stress reactive oxygen species
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Protective effects of organic extracts of Alpinia oxyphylla against hydrogen peroxide-induced cytotoxicity in PC12 cells 预览
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作者 Li-Hong Duan Meng Li +10 位作者 Chun-Bao Wang Qing-Mei Wang Quan-Quan Liu Wan-Feng Shang Ya-Jin Shen Zhuo-Hua Lin Tong-Yang Sun Zheng-Zhi Wu Ying-Hong Li Yu-Long Wang Xun Luo 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第4期682-689,共8页
Alpinia oxyphylla,a traditional herb,is widely used for its neuroprotective,antioxidant and memory-improving effects.However,the neuroprotective mechanisms of action of its active ingredients are unclear.In this study... Alpinia oxyphylla,a traditional herb,is widely used for its neuroprotective,antioxidant and memory-improving effects.However,the neuroprotective mechanisms of action of its active ingredients are unclear.In this study,we investigated the neuroprotective effects of various organic extracts of Alpinia oxyphylla on PC12 cells exposed to hydrogen peroxide-induced oxidative injury in vitro.Alpinia oxyphylla was extracted three times with 95%ethanol(representing extracts 1–3).The third 95%ethanol extract was dried and resuspended in water,and then extracted successively with petroleum ether,ethyl acetate and n-butanol(representing extracts 4–6).The cell counting kit-8 assay and microscopy were used to evaluate cell viability and observe the morphology of PC12 cells.The protective effect of the three ethanol extracts(at tested concentrations of 50,100 and 200μg/mL)against cytotoxicity to PC12 cells increased in a concentration-dependent manner.The ethyl acetate,petroleum ether and n-butanol extracts(each tested at 100,150 and 200μg/mL)had neuroprotective effects as well.The optimum effective concentration ranged from 50–200μg/mL,and the protective effect of the ethyl acetate extract was comparatively robust.These results demonstrate that organic extracts of Alpinia oxyphylla protect PC12 cells against apoptosis induced by hydrogen peroxide.Our findings should help identify the bioactive neuroprotective components in Alpinia oxyphylla. 展开更多
关键词 active INGREDIENTS ALPINIA oxyphylla apoptosis ethanol crude extract fraction hydrogen PEROXIDE nerve regeneration NEUROPROTECTIVE agent NEUROPROTECTIVE effects PC12 cells traditional HERB
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Protective effect of hydrogen sulfide on oxidative stress-induced neurodegenerative diseases 预览
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作者 Rubaiya Tabassum Na Young Jeong Junyang Jung 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第2期232-241,共10页
Hydrogen sulfide is an antioxidant molecule that has a wide range of biological effects against oxidative stress. Balanced oxidative stress is also vital for maintaining cellular function in biological system, where r... Hydrogen sulfide is an antioxidant molecule that has a wide range of biological effects against oxidative stress. Balanced oxidative stress is also vital for maintaining cellular function in biological system, where reactive oxygen species are the main source of oxidative stress. When the normal redox balance is disturbed, deoxyribonucleic acid, lipid, and protein molecules are oxidized under pathological conditions, like diabetes mellitus that leads to diabetic peripheral neuropathy. In diabetes mellitus-induced diabetic peripheral neuropathy, due to hyperglycemia, pancreatic beta cell(β cell) shows resistance to insulin secretion. As a consequence, glucose metabolism is disturbed in neuronal cells which are distracted from providing proper cell signaling pathway. Not only diabetic peripheral neuropathy but also other central damages occur in brain neuropathy. Neurological studies regarding type 1 diabetes mellitus patients with Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis have shown changes in the central nervous system because high blood glucose levels(HbA1 c) appeared with poor cognitive function. Oxidative stress plays a role in inhibiting insulin signaling that is necessary for brain function. Hydrogen sulfide exhibits antioxidant effects against oxidative stress, where cystathionine β synthase, cystathionine γ lyase, and 3-mercaptopyruvate sulfurtransferase are the endogenous sources of hydrogen sulfide. This review is to explore the pathogenesis of diabetes mellitus-induced diabetic peripheral neuropathy and other neurological comorbid disorders under the oxidative stress condition and the anti-oxidative effects of hydrogen sulfide. 展开更多
关键词 Alzheimer's DISEASE amyotrophic lateral SCLEROSIS antioxidant diabetic peripheral NEUROPATHY DNA oxidation hydrogen SULFIDE mitochondrial dysfunction oxidative stress Parkinson's DISEASE reactive oxygen species
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日本氢能技术发展现状 预览
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作者 贾光 《安全.健康和环境》 2019年第8期1-4,共4页
为提高能源自给率、减少CO2排放,日本将氢能列入“能源战略计划”,并制定了“氢和燃料电池战略路线图”。介绍了日本加氢站的氢气来源和储运方式、家用燃料电池系统及其使用情况,以及日本在热化学水分解循环制氢、甲苯/甲基环己烷储氢... 为提高能源自给率、减少CO2排放,日本将氢能列入“能源战略计划”,并制定了“氢和燃料电池战略路线图”。介绍了日本加氢站的氢气来源和储运方式、家用燃料电池系统及其使用情况,以及日本在热化学水分解循环制氢、甲苯/甲基环己烷储氢系统、液氨储氢系统方面开展的研究,总结了氢气的危险特性。 展开更多
关键词 氢能 加氢站 储氢系统 家用燃料电池系统
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氢气洗涤塔运行中存在的问题及改进措施 预览
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作者 梁寅祥 刘伟 《氯碱工业》 CAS 2019年第7期16-17,共2页
介绍了氢气处理工艺流程。针对原氢气处理工艺过程中过滤器常堵塞的问题,从2方面改进了氢气洗涤塔工艺:①控制源头,改变水质;②对喷淋嘴进行钝化处理。改造后,解决了氢气洗涤塔在运行中出现的结垢、喷嘴堵塞、洗涤不充分等问题,同时降... 介绍了氢气处理工艺流程。针对原氢气处理工艺过程中过滤器常堵塞的问题,从2方面改进了氢气洗涤塔工艺:①控制源头,改变水质;②对喷淋嘴进行钝化处理。改造后,解决了氢气洗涤塔在运行中出现的结垢、喷嘴堵塞、洗涤不充分等问题,同时降低了检维修费用,提高了生产系统的稳定性。 展开更多
关键词 氢气 氢气处理 氢气洗涤塔 冷却器
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Effect of the Suppression of Cariesitic Bacterial Growth and Biofilm Formation Using Hydrogen/Free Chlorine Mixed Water Produced by an Electrolysis-Type Hydrogen Generator 预览
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作者 Ryusuke Suzuki Rin Kaneko +5 位作者 Masaru Nakano Masato Kanda Yuji Sebata Shota Motegi Tomoko Abe Kazuaki Muramatsu 《健康(英文)》 2019年第2期142-151,共10页
OBJECTS: Hydrogen has been shown to possess antibacterial effects at high concentrations. In addition, chlorine has a strong bactericidal effect even at low concentrations. Electrolysis is a way to simultaneously gene... OBJECTS: Hydrogen has been shown to possess antibacterial effects at high concentrations. In addition, chlorine has a strong bactericidal effect even at low concentrations. Electrolysis is a way to simultaneously generate these two components. However, the concentration of hydrogen/free chlorine mixed water generated through electrolysis decreases quickly. It is predicted that the concentration of hydrogen/free chlorine mixed water will vary depending on the quality of water used. After investigating the optimum generation conditions, the effects of the most stable concentration of hydrogen/free chlorine mixed water on carious tooth fungus were evaluated in vitro. Thus, in this experiment, our goal was to evaluate the effects of hydrogen/free chlorine mixed water on oral bacteria. MATERIALS AND METHODS: Using a device that generates hydrogen/free chlorine through electrolysis, the differences in the concentrations of hydrogen and free chlorine based on electrolysis time were evaluated using tap water. Additionally, various concentration changes due to electrolysis time on the hydrogen/free chlorine mixed water were evaluated. Distilled tap water as a control group, hydrogen/free chlorine mixed water, and commercially available mouthwash were added for 1 minute to cultured Streptococcus mutans and then rinsed out with the culture medium. Bacterial growth (600 nm) and biofilm formation (590 nm) were measured at 3 and 6 hours after the addition of the medium. RESULTS: The concentration of hydrogen/chlorine mixed water produced by electrolysis varied depending on electrolysis time and the water used. The inhibitory effect of bacterial growth was enhanced depending on the chlorine concentration. Regarding the inhibitory effect on biofilm formation, only the mixed water of hydrogen/free chlorine concentration (500 ppb - 1.0 mg/L) had a suppressing effect after 6 hours. CONCLUSION: It was suggested that hydrogen/chlorine mixed water can be easily produced by electrolysis and has the effect of suppressing the growth of d 展开更多
关键词 HYDROGEN CHLORINE BACTERICIDAL Capacity Bacteria EFFECT
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Newly developed two-dimensional materials for efficient photocatalytic hydrogen evolution
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作者 Xueying Zhan Fengmei Wang +2 位作者 Zhongzhou Cheng Zhenxing Wang Jun He 《科学通报:英文版》 SCIE EI CSCD 2019年第14期958-960,共3页
Due to the increasing environmental and energy issues, hydrogen, as a clean and non-carbon energy source, has received more and more attention in the past decades. Photocatalysis has been known as a promising approach... Due to the increasing environmental and energy issues, hydrogen, as a clean and non-carbon energy source, has received more and more attention in the past decades. Photocatalysis has been known as a promising approach for hydrogen generation and a key measure in solving serious environmental problems. Different from traditional catalysts, such as ZnO and TiO2, two-dimensional (2D) materials display unique advantages to hydrogen production due to their large specific surface area, high charge migration rate, tunable electronic structure and ultra-lightweight [1]. Especially, 2D materials show short migration distance for the generated electrons and holes, leading to the reduction of electron-hole recombination, which is one of the key factors affecting photocatalytic efficiency [2-4]. 展开更多
关键词 NEWLY DEVELOPED TWO-DIMENSIONAL MATERIALS PHOTOCATALYTIC HYDROGEN evolution HYDROGEN generation
新能源制氢技术发展现状及前景分析 预览
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作者 黄格省 阎捷 +2 位作者 师晓玉 卢红 鲜楠莹 《石化技术与应用》 CAS 2019年第5期289-296,共8页
介绍了化学链制氢、生物质制氢、利用弃风/弃光电解水制氢、太阳能光催化分解水制氢等新型清洁能源制氢技术的研究与应用现状,对各种制氢技术的产业发展前景进行了分析。在氢燃料电池汽车产业发展过程中,化石原料制氢(包括工业副产氢气... 介绍了化学链制氢、生物质制氢、利用弃风/弃光电解水制氢、太阳能光催化分解水制氢等新型清洁能源制氢技术的研究与应用现状,对各种制氢技术的产业发展前景进行了分析。在氢燃料电池汽车产业发展过程中,化石原料制氢(包括工业副产氢气及化合物热分解制氢)仍将是制氢技术中的主流工艺路线,而生物质制氢、“绿电”电解水制氢、太阳能光催化分解水制氢等新能源制氢是化石原料制氢的重要补充,未来的氢气生产将呈现化石原料路线和可再生原料路线优势互补、多元化并存发展的格局。为推动新型清洁制氢技术的快速发展,建议我国政府应从国家层面持续做好顶层设计,对新能源制氢产业化项目给予产业政策扶持;国内科研院所应加强与企业的技术研发合作,加大开发绿色、低碳、低成本制氢技术,推动制氢技术进步和氢燃料电池汽车产业快速成长。 展开更多
关键词 氢气 化学链 生物质 电解水 风能 太阳能 燃料电池 发展前景
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Improved hydrogen storage properties of LiBH4 confined with activated charcoal by ball milling
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作者 He Zhou Xin-Hua Wang +2 位作者 Hai-Zhen Liu Shi-Chao Gao Mi Yan 《稀有金属:英文版》 SCIE EI CAS CSCD 2019年第4期321-326,共6页
In order to enhance the hydrogen storage properties of LiBH4,activated charcoal (AC) was used as the scaffold to confine LiBH4 in this paper.Ball milling was used to prepare LiBH4/AC composites.Experimental results sh... In order to enhance the hydrogen storage properties of LiBH4,activated charcoal (AC) was used as the scaffold to confine LiBH4 in this paper.Ball milling was used to prepare LiBH4/AC composites.Experimental results show that dehydrogenation properties of ball-milled LiBH4/AC (LiBH4/AC-BM) are greatly improved compared with that of pristine LiBH4,ball-milled LiBH4 (LiBH4-BM) and hand-milled LiBH4/AC (LiBH4/AC-HM).The onset dehydrogenation temperature of LiBH4 for LiBH4/AC-BM is around 160 ℃,which is 170 ℃ lower than that of pristine LiBH4.At around 400 ℃,LiBH4/AC-BM finishes the dehydrogenation with a hydrogen capacity of 13.6 wt%,which is approximately the theoretical dehydrogenation capacity of pure LiBH4 (13.8 wt%),while the dehydrogenation processes for LiBH4-BM and LiBH4/AC-BM do not finish even when they were heated to 600 ℃.The isothermal dehydriding measurements show that it takes only 15 min for LiBH4/AC-BM to reach a dehydrogenation capacity of 10.1 wt% at 350 ℃,whereas the pristine LiBH4 and the LiBH4/AC-HM release hydrogen less than 1 wt% under the same conditions.The dehydrogenation process and the effect of AC were discussed. 展开更多
关键词 HYDROGEN STORAGE properties HYDROGEN STORAGE materials LITHIUM BOROHYDRIDE Activated charcoal
氯碱企业副产氢气用于氢燃料电池现状及前景分析 预览
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作者 李宁 赵国良 +2 位作者 王志元 商付滨 曹长青 《中国氯碱》 CAS 2019年第8期1-3,共3页
以氯碱企业对氢气的利用现状为切入点,深入研究氢气与氢燃料电池的技术特点并分析其未来发展与应用前景。
关键词 氯碱企业 氢气 氢燃料电池 现状及前景
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降低1000 MW超超临界二次再热机组发电机漏氢量 预览
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作者 李敏 《电力系统装备》 2019年第14期92-93,共2页
本文对某电厂1000MW二次再热机组发电机漏氢量偏大、补氢频繁的情况进行了分析,并对发电机本体以及相关密封油、氢气、定冷水系统进行排查分析,发现密封油温度设置不合理对发电机漏氢有较大影响。针对此问题,提出相应的解决方法,采取措... 本文对某电厂1000MW二次再热机组发电机漏氢量偏大、补氢频繁的情况进行了分析,并对发电机本体以及相关密封油、氢气、定冷水系统进行排查分析,发现密封油温度设置不合理对发电机漏氢有较大影响。针对此问题,提出相应的解决方法,采取措施后漏氢情况明显得到改善。 展开更多
关键词 发电机 氢气 漏氢 密封油
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NiPt nanoparticles supported on CeO2 nanospheres for efficient catalytic hydrogen generation from alkaline solution of hydrazine
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作者 Yana Men Jun Su +3 位作者 Xiangli Wang Ping Cai Gongzhen Cheng Wei Luo 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第3期634-637,共4页
Searching for highly efficient catalysts toward dehydrogenation of hydrazine for chemical hydrogen storage is highly desirable for the development of hydrogen economy. Herein, we report a simple in situ co-reduction s... Searching for highly efficient catalysts toward dehydrogenation of hydrazine for chemical hydrogen storage is highly desirable for the development of hydrogen economy. Herein, we report a simple in situ co-reduction synthesis of NiPt nanoparticles supported on CeO2 nanospheres and their superior catalytic performance for hydrogen generation from alkaline solution of hydrazine at room temperature. Thanks to the strong electronic interaction arising from synergistic effect at atomic lever and support-metal interaction between NiPt and CeO2.The obtained Ni5Pt5-CeO2 catalyst exhibits 100% hydrogen selectivity and superior catalytic performance for hydrogen generation from alkaline solution of hydrazine at room temperature, with a TOF value of 416 h 1. 展开更多
关键词 HYDROGEN storage HYDRAZINE HYDROGEN evolution CEO2 NANOSPHERES Support-metal in teraction
氨硼烷分解制氢及其再生的研究进展 预览
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作者 李燕 邓雨真 +1 位作者 俞晶铃 黎四芳 《化工进展》 EI CAS CSCD 北大核心 2019年第12期5330-5338,共9页
氨硼烷具有储氢密度高(152.9g/L)、放氢条件温和、无毒以及常温下为稳定的固体而易于储运等特点而成为最有前景的储氢材料之一。本文综述了近年来氨硼烷在不同催化剂作用下,通过热解、醇解和水解这3种方式制氢以及分解后的副产物循环再... 氨硼烷具有储氢密度高(152.9g/L)、放氢条件温和、无毒以及常温下为稳定的固体而易于储运等特点而成为最有前景的储氢材料之一。本文综述了近年来氨硼烷在不同催化剂作用下,通过热解、醇解和水解这3种方式制氢以及分解后的副产物循环再生氨硼烷的研究进展。分析讨论了氨硼烷的热解制氢研究主要集中在降低温度和抑制气态副产物的生成这两方面,而水解或醇解制氢的研究热点是二元或三元非贵金属纳米核壳或负载型催化剂。与氨硼烷的热解相比,水解或醇解由于条件温和、制氢速度快而更具实用性。指出氨硼烷作为储氢材料最大的挑战是其再生问题,氨硼烷分解脱氢后的副产物不能直接氢化而再生氨硼烷,需要通过一系列反应来进行间接的离线再生,因此氨硼烷的再生将是今后的重点研究方向。 展开更多
关键词 氨硼烷 催化剂 储氢材料 再生
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Investigating the Use of Combined Hydrogen, Heat and Power System for Omar AL-Mukhtar University Campus 预览
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作者 Moutaz Benali Tarek Hamad +1 位作者 Ahmad Belkhair Yousif Hamad 《生物化学进展(英文)》 2019年第1期31-44,共14页
This paper investigates the use of a combined hydrogen, heat, and power (CHHP) system for Omar Al-Mukhtar University campus using local resources. Based on previous local resource assessment studies, the hydrogen team... This paper investigates the use of a combined hydrogen, heat, and power (CHHP) system for Omar Al-Mukhtar University campus using local resources. Based on previous local resource assessment studies, the hydrogen team of Omar AL-Mukhtar University (OMU) selected the fuelcell energy DFC4000TM unit. This study shows that the CHHP system can provide electricity to power the university campus, thermal energy for heating the anaerobic digester, and hydrogen for transportation, back-up power and other needs. Consequently, using the alternative fuels and renewable energy resources for OMU campus can lower fossil fuel consumption and, therefore, greenhouse gas emissions (GHG). 展开更多
关键词 HYDROGEN FEEDSTOCK ANAEROBIC DIGESTION Pressure SWING Adsorption RENEWABLE Energy
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氢气制备技术的研究进展 预览
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作者 李永恒 陈洁 +4 位作者 刘城市 杨云 李菲晖 巩运兰 刘美华 《电镀与精饰》 CAS 北大核心 2019年第10期22-27,共6页
氢气作为一种清洁、无污染、燃烧热值高的新型能源,是目前新能源的研究热点之一,因而研究氢气的制备对未来有着巨大的影响。本文系统的介绍了目前各类制氢方法的现状以及它们的优缺点,着重介绍电解水制氢的途径和思路,囊括了碱性电解水... 氢气作为一种清洁、无污染、燃烧热值高的新型能源,是目前新能源的研究热点之一,因而研究氢气的制备对未来有着巨大的影响。本文系统的介绍了目前各类制氢方法的现状以及它们的优缺点,着重介绍电解水制氢的途径和思路,囊括了碱性电解水制氢、PEM电解水制氢和固体氧化物电解水制氢的原理,指出它们现存的瓶颈问题及改进方法,并对未来制氢和氢能源的发展进行了展望。 展开更多
关键词 能源 氢气 水制氢 电解水
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电解水制氢MoS2催化剂研究与氢能技术展望 预览 被引量:1
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作者 王培灿 雷青 +1 位作者 刘帅 王保国 《化工进展》 EI CAS CSCD 北大核心 2019年第1期278-290,共13页
氢气具有质量轻、热值高、燃烧产物清洁等优点,被认为是理想的能源载体。氢气既能作为燃料电池的燃料,又能作为储能介质调节风能、太阳能发电系统的随机性、间歇性,正在成为未来能源的重要组成部分。为了促进电解水制氢技术与装备发展,... 氢气具有质量轻、热值高、燃烧产物清洁等优点,被认为是理想的能源载体。氢气既能作为燃料电池的燃料,又能作为储能介质调节风能、太阳能发电系统的随机性、间歇性,正在成为未来能源的重要组成部分。为了促进电解水制氢技术与装备发展,研究高效电催化剂十分重要。本文围绕“粉末型”与“自支撑型”电催化剂结构特征,讨论基于二硫化钼(MoS2)的析氢电催化剂的研究现状,阐述了催化活性位点调控策略与提高导电性两条技术途径,并以析氢过电位和塔菲尔曲线斜率为依据,比较不同方法制备的二硫化钼电催化剂的催化活性。表明提高二硫化钼晶相稳定性、调节其电子结构和优化催化电极结构等方法,将进一步提高基于二硫化钼的析氢催化电极性能。 展开更多
关键词 电催化剂 二硫化钼 电解水 制氢
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光催化分解水制备氢气和过氧化氢 预览 被引量:1
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作者 王利超 曹爽 +3 位作者 郭凯 吴志娇 马智 朴玲钰 《催化学报》 SCIE EI CAS CSCD 北大核心 2019年第3期470-475,共6页
过氧化氢不仅是一种广泛应用于化学合成、消毒、废水处理及纸浆漂白等领域的高价值化学品,还是一种具有潜力的能源载体.此外,过氧化氢燃料电池因其结构简单而受到广泛关注.蒽醌法是工业生产过氧化氢的传统方法,但是这种方法不仅能耗高,... 过氧化氢不仅是一种广泛应用于化学合成、消毒、废水处理及纸浆漂白等领域的高价值化学品,还是一种具有潜力的能源载体.此外,过氧化氢燃料电池因其结构简单而受到广泛关注.蒽醌法是工业生产过氧化氢的传统方法,但是这种方法不仅能耗高,而且生产过程会造成严重的环境问题.因此,通过环保并且低成本的工艺直接合成过氧化氢具有重要研究意义.以太阳能为动力的光催化法生产过氧化氢被认为是最有前景的方法之一.目前,光催化已在制氢、二氧化碳还原和水处理等诸多领域取得了重要进展.但是,利用光催化分解水制备过氧化氢的研究还非常少.尽管通过光催化还原氧气可以制备过氧化氢,但是通过分解水同时制备高价值过氧化氢和氢气更具有吸引力.在本项工作中,我们利用Pt/TiO2(锐钛矿)光催化剂在没有牺牲剂的条件下实现了高效产氢和过氧化氢,氢气和过氧化氢的生成速率分别达到7410和5096μmolg–1h–1(第一小时),远高于市售的Pt/TiO2(锐钛矿)体系和文献报道数值.本文采用X射线光电子能谱(XPS)、电子自旋共振(ESR)和荧光标记法等表征手段研究了Pt/TiO2上同时生成氢气和过氧化氢的催化机理.XPS测试结果表明,Pt/TiO2在光照射1h后,XPS信号发生明显变化.与其他样品相比,物理吸附水和羟基的峰明显增加.因此,我们推测羟基和物理吸附水对过氧化氢的生成具有重要影响.进一步采用电子自旋共振(ESR)和荧光标记法对羟基进行了测量.ESR结果显示,紫外光照60s即可检测到羟基捕获剂与羟基的结合物5,5-dimethyl-1-pyrroline-N-oxide-OH(DMPO-OH)的特征峰.此外,在体系中加入荧光标记分子对苯二甲酸(TANa)后也可以迅速检测到2-羟基对苯二甲酸(TAOH)在422nm处明显的荧光信号.因此,ESR和荧光结果均表明所产生的羟基自由基在过氧化氢形成中起着重要作用.上述结果表明,在本体系� 展开更多
关键词 光催化分解水 氢气 过氧化氢 锐钛矿
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氢气型溴化锂制冷机组运行总结 预览
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作者 费信怀 彭靖 《氯碱工业》 CAS 2019年第6期33-35,40共4页
介绍了以氢气为热能制取7℃冷冻水的溴化锂机组的工艺流程及运行情况,分析了机组在运行过程中存在的问题,并提出了解决及改造措施。
关键词 溴化锂 制冷机组 氢气 高压发生器 水封罐 真空度 氢气压力
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TiAlN/TiMoN Coatings as Hydrogen Barriers 预览
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作者 Motonori Tamura Hidekazu Takizawa 《材料科学与工程:中英文A版》 2019年第1期1-7,共7页
We evaluated the hydrogen barrier properties of a multi-layered coating of TiAlN/TiMoN.Coatings facilitated reductions of the hydrogen permeabilities to 1/1,000 of that of the uncoated substrate.The experiment confirm... We evaluated the hydrogen barrier properties of a multi-layered coating of TiAlN/TiMoN.Coatings facilitated reductions of the hydrogen permeabilities to 1/1,000 of that of the uncoated substrate.The experiment confirmed that the coatings composed of fine crystal grains were highly effective as hydrogen barriers,and that this barrier property became even more efficient if multiple layers of the coatings were applied.The crystal grain boundaries of the coating and interfaces of each film in a multi-layered coating can serve as hydrogen trapping sites.We speculate that fine crystal structures with multiple crystal grain boundaries and multi-layered coating interfaces will contribute to the development of hydrogen barriers. 展开更多
关键词 HYDROGEN PERMEATION multi-layered-coating microstructure HYDROGEN TRAPS
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减缓柴油加氢装置硫化氢汽提塔顶空冷腐蚀的工艺研究 预览
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作者 陈金仙 周尚 《化工设计通讯》 CAS 2019年第5期99-100,共2页
柴油加氢装置通过加氢反应将柴油馏分中的噻吩等硫化物转化为硫化氢,通过闪蒸和蒸汽汽提的方式脱除柴油馏分中溶解的硫化氢。硫化氢汽提塔顶空冷普遍出现管束腐蚀穿孔的现象。荆门石化加氢改质装置由热高分调整为温高分流程,汽提塔空冷... 柴油加氢装置通过加氢反应将柴油馏分中的噻吩等硫化物转化为硫化氢,通过闪蒸和蒸汽汽提的方式脱除柴油馏分中溶解的硫化氢。硫化氢汽提塔顶空冷普遍出现管束腐蚀穿孔的现象。荆门石化加氢改质装置由热高分调整为温高分流程,汽提塔空冷腐蚀严重,经常腐蚀穿孔,存在较大安全隐患。因此,拟通过对工艺条件进行调整,以降低硫化氢汽提塔顶空冷器腐蚀,延长设备使用寿命。 展开更多
关键词 柴油加氢 硫化氢 腐蚀 氢气汽提
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