Results 31 to 40 of about 4,736 (178)

阿克苏断层氢气浓度动态特征及其映震效能

open access: yesDizhen xuebao, 2021
首先对阿克苏断层氢气浓度观测资料的周期成分进行了时频分析,然后分别利用线性回归和互相关方法分析了气温、气压与氢气浓度年周期成分的关系,并利用Molchan图表法对阿克苏断层氢气的映震效能进行了定量检验。结果显示:① 阿克苏断层氢气浓度具有清晰的年周期和半日周期成分;② 阿克苏断层氢气浓度的年周期动态变化与气温具有显著的正相关性,与气压的相关性一般,表明其年周期变化主要受气温影响;③ 阿克苏断层氢气浓度异常对观测点周边中强以上地震的反应较灵敏,映震效果较好。
Jun Zhong, Bo Wang, Wei Yan, Yuchuan Ma
doaj   +1 more source

Effect of optical isomerism of α -Ala molecules with hydrogen bonds between carboxyl groups and amino and the roles of hydroxyl radicals and hydroxyl group in water environment(水环境下羧基与氨基间为单氢键的α-Ala 旋光异构及羟自由基和氢氧根的作用)

open access: yesZhejiang Daxue xuebao. Lixue ban, 2019
采用密度泛函理论的B3LYP 方法、微扰理论的MP2 方法和自洽反应场(SCRF) 理论的SMD 模型方法,研究了水环境下羧基与氨基间为单氢键的α-Ala 旋光异构及羟自由基和氢氧根作用的反应。研究发现:α- Ala 的旋光异构可在a 和b 两个通道实现,a 通道为羧基顺反异构后,水分子簇作媒介质子以氨基为桥从α 碳的一侧向另一侧迁移;b 通道为水分子簇作媒介,质子从α 碳向氨基氮的迁移与羧基顺反异构协同进行。在a 通道,羟自由基水分子簇可致α-Ala 损伤。势能面计算表明:水环境下,在a 通道3 ...
YANHongyan(闫红彦)   +3 more
doaj   +1 more source

美国国家氢能计划及其启示 [PDF]

open access: yes, 2015
通过对美国国家氢能计划的发起及发展历程、组织管理模式、科研体系、实施流程及评估过程进行考察与分析,探讨以政府为主导的应用性科研规划的特征及成功经验 ...
刘益东, 王彦雨, 高璐
core  

Developing HMME‐Conjugated NIR‐II Activated Carbon Dots Nanospray for the Treatment of MRSA Biofilm Infections in Diabetic Wound via PTT/CDT/SDT

open access: yesRare Metals, Volume 45, Issue 4, April 2026.
ABSTRACT Diabetic wound infections are a common complication of diabetes, which severely impact patients' quality of life. Effective treatment of diabetic wound infections remains one major challenge in the clinic, partially due to the formation of bacterial biofilm and antibiotic resistance.
Liang Zhou   +8 more
wiley   +1 more source

Advanced NPs catalysts prepared by Nanoparticles Beam Composite Deposition System [PDF]

open access: yes, 2016
当前社会的发展对能源,尤其是对化石能源的需求日益扩大。化石能源作为一种不可再生资源供需缺口逐渐增大,而且其在利用过程中常伴随着严重的环境污染问题。燃料电池和氢能源作为一种新型绿色能源引起了人们越来越多的重视,具有长远的应用前景和重要的研究意义。直接甲酸燃料电池和电解析氢作为其中关键技术,已得到了大量的关注和长足的发展。目前采用的Pt及Pt基纳米催化剂存在造价高,活性低和寿命短等诸多问题,严重阻碍着燃料电池和氢能源的全面商业化运作。 本文采用课题组自主研发的纳米粒子束流复合沉积系统 ...
林城伟
core  

Designing 3d Transition‐Metal Doped g‐C3N4 Monolayer for Enhanced Bifunctional Oxygen Evolution/Reduction Reactions Activity: Defect Physics and Constant‐Potential Study

open access: yesRare Metals, Volume 45, Issue 4, April 2026.
ABSTRACT Graphitic carbon nitride (g‐C3N4) doped with 3d transition metals (3d‐TM@g‐C3N4) has gained attention as a noble metal‐free alternative for oxygen evolution and reduction reactions (OER/ORR). Yet the key mechanisms driving its performance remain debated, especially across different charge states.
Jing Zhang   +6 more
wiley   +1 more source

Over-expression of Xylose isomerase/Xylulokinase and Construction of O2-tolerant hydrogenase in Klebsiella oxytoca HP1 [PDF]

open access: yes, 2015
在石化燃料枯竭和全球气候变暖的双重危机下,氢气作为一种可再生、零排放和高热值的清洁能源载体而备受关注。关于氢能的研究主要围绕氢的制取和氢的利用两个方面展开。在众多制氢方式中,生物制氢因其生产成本低、原料来源丰富和环境污染小,从而成为制氢研究的热点。在氢的利用中,燃料电池技术一直以来都是研究的重点。氢酶是一种含金属的氧化还原酶,其广泛存在于微生物中,能够可逆地催化H+的还原和H2的氧化(2H++2e-↔H2)。无论是在氢的制取还是氢的利用中,氢酶都是氢能技术的核心之一 ...
黄钢锋
core  

Pyrolysis‐Engineered Fe/Mn‐ZIF Catalysts: Balancing Activity, Selectivity, and Stability for the Oxygen Reduction Reaction

open access: yesRare Metals, Volume 45, Issue 4, April 2026.
ABSTRACT Metal oxide‐based catalysts for oxygen reduction reaction (ORR) have drawn great attention in recent years. However, it remains technically challenging for the precise regulation of the overall performance due to the trade‐off effect among the activity, selectivity, and stability of electrocatalysts. Herein, a balancing strategy to control the
Haoran Ma   +7 more
wiley   +1 more source

The diversity and physiological characteristics of microbes involved in hydrogen metabolism from deep-sea hydrothermal vent fields [PDF]

open access: yes, 2015
由微生物介导的发酵产氢由于具有众多的优点,在制氢方面可能具有更大的生产潜力。深海热液系统具有特殊生态环境,与陆地和海洋中的其他生物群落有着根本的区别。本研究针对深海热液环境开展氢代谢菌的研究工作,以期获得特殊生境中的氢代谢微生物资源和氢酶资源。 利用西南印度洋,南大西洋,东太平洋等不同来源的深海热液环境样品,进行了氢代谢菌的分离培养工作。共获得7个高温发酵产氢富集培养物。细菌16SrRNA基因序列分析表明,富集培养物中的主要类群是Calroanaerobacter,Clostridium ...
姜丽晶
core  

A Review on Cu‐Based Catalysts for Dehydrogenation of Chemical Hydrides

open access: yesRare Metals, Volume 45, Issue 4, April 2026.
ABSTRACT Hydrogen (H2) plays a crucial part in the building of clean and sustainable energy systems due to its advantages of being renewable, clean, and pollution‐free. Nevertheless, the secure and effective production‐storage‐transportation of H2 presents critical challenges.
Yixing Luo   +6 more
wiley   +1 more source

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