Results 21 to 30 of about 22,800 (217)

氢气/氧气混合气体等离子体放电动力学机理

open access: yesGaoya dianqi, 2020
针对绿色无毒推进剂航天器火箭发动机真空低温条件下点火困难等问题,提出通过放电产生非平衡等离子体,利用其活化效应改善发动机点火性能。为了研究氢、氧混合气体放电产生的活性粒子的时间演化特性,利用Bolsig+求解器计算得到不同电子碰撞反应能量损失分数随约化场强变化规律;利用ZDplaskin程序包对氢、氧混合气体放电过程进行零维仿真;研究了不同约化场强下混合气体活性粒子随时间变化规律。结果表明,不同约化场强下,氢、氧混合气体中各类电子碰撞反应消耗能量占比不同。约化场强较小的情况下 ...
郑体凯   +4 more
doaj  

Lipid Nanoparticles Delivering ClpP‐mRNA Suppress Pyroptosis and Senescence in Intervertebral Disc Degeneration via mTOR/BNIP3‐Activated Mitophagy

open access: yesRare Metals, EarlyView.
ABSTRACT Intervertebral disc degeneration (IDD) is a predominant cause of low back pain, significantly impacting quality of life. Mitochondrial fitness is essential in the progression of IDD, as it regulates cellular senescence and pyroptosis. This study investigates the role of mitochondrial caseinolytic protease P (ClpP) in alleviating senescence and
Kun Wang   +7 more
wiley   +1 more source

磷素活化剂对红壤磷形态及有效性影响的研究

open access: yesShuitu Baochi Xuebao, 2011
在我国南方红壤中加入不同的磷活化剂进行培养试验,结果显示:磷活化剂提高了土壤有效磷含量,不同活化剂的活化能力不同。相关分析和通径分析结果表明,磷活化剂的活化能力大小顺序为:低分子有机酸钠钙盐>腐植酸>腐植酸钠>脲基甲酸乙酯;磷活化剂可以提高红壤中的Al-P、Ca-P和Fe-P等无机磷含量,其中Al-P和Ca-P与有效磷均达到极显著水平,而Fe-P作用效果不显著,可以通过影响Al-P和Ca-P来间接影响有效磷,磷活化剂会抑制土壤中O-P的生成。
李杰   +4 more
doaj  

Chemical Synthesis of Lactic Acid from Lignocellulosic Compouds Catalysed by Pb(II) or Al(III)-Sn(II) [PDF]

open access: yes, 2015
催化转化自然界中含量丰富且可再生的纤维素类生物质资源制备平台化学品有非常重要的意义。尤其是,在非氢条件下将纤维素转化为与其化学组成类似的乳酸,是纤维素转化中最具原子经济效益的路径之一,然而相关的研究尚十分有限。本篇论文研究了氮气氛下,简单金属离子Pb(II)和离子组合Al(III)-Sn(II)催化纤维素及其单体葡萄糖转化为乳酸反应,主要取得以下结果: 研究发现,简单金属离子Pb(II)可有效地催化纤维素及葡萄糖转化制乳酸。氮气氛下,在463K反应6h后,Pb(II)催化球磨纤维素制乳酸的收率高达70 ...
王焱良
core  

N,W‐Cooperative Modulation of Ni3S2 for Efficient Electrocatalytic Oxidation of 5‐Hydroxymethylfurfural to 2,5‐Furandicarboxylic Acid

open access: yesRare Metals, EarlyView.
ABSTRACT Ni3S2 has emerged as a promising catalyst for the electrochemical oxidation of biomass‐derived 5‐hydroxymethylfurfural (HMF) to 2,5‐furandicarboxylic acid (FDCA), driven by its distinctive physicochemical properties. However, its practical catalytic efficiency is severely hindered by abundant electrochemically inactive surface sites and poor ...
Cheng‐Feng Yi   +5 more
wiley   +1 more source

Fabrication‐Driven Oxidation Pathways in Y/Hf‐Modified High‐Entropy Alloys: From Elemental Segregation to Oxide Homogeneity

open access: yesRare Metals, EarlyView.
ABSTRACT This study elucidates the oxidation mechanisms governing Y/Hf‐doped AlCoCrFeNiTi high‐entropy alloys (HEAs) and reveals the pivotal role of fabrication processes in dictating high‐temperature oxidation behavior. We demonstrate that casting and spark plasma sintering (SPS) promote Y/Hf segregation, resulting in heterogeneous oxide formation and
Huaqing Yi   +5 more
wiley   +1 more source

Modification of radiation effect on cultured human cells [PDF]

open access: yes, 1984
Thesis--University of Tsukuba, D.M.S.(A), no. 248, 1984.
Eguchi Kiyomi
core  

Engineering 2D Materials for High‐Current‐Density Electrocatalytic Water Splitting

open access: yesRare Metals, EarlyView.
ABSTRACT Water electrolysis is a key method for sustainable hydrogen production, using water as an abundant resource. However, efficient and stable operation at high current densities remains challenging due to energy losses, catalyst degradation, and limited ion–electron transport.
Tianqi Guan   +8 more
wiley   +1 more source

Synthesis of Aromatic Amines by Pd / C Catalytic Hydrogenation Aromatic Nitro-compounds [PDF]

open access: yes, 2015
以5%Pd/C为催化剂,芳香族硝基化合物在温和条件(30℃,H2/0.1 MPa)下还原成芳胺。研究了芳环上的取代基对催化加氢反应的影响。结果表明:对位取代的芳硝基化合物的加氢反应速率为:H>CH3>CO2CH3>CF3>F>OCH3;间位取代芳硝基化合物加氢反应速率为:H>CH3>CF3>F>CO2CH3>OCH3>CN;邻位取代芳硝基化合物加氢反应速率为:H>CF3>CH3>OCH3>F>CO2CH3 ...
兰丽娟   +5 more
core   +1 more source

Smart Biomaterials and Dressings for the Treatment of Chronic Inflammatory Skin Diseases

open access: yesRare Metals, EarlyView.
ABSTRACT Chronic inflammatory skin diseases, encompassing immune‐inflammatory conditions and infection‐associated dermatoses, pose significant clinical challenges due to high prevalence, recurrence, and therapeutic resistance, affect over 30% of the global population.
Zehao Lan   +5 more
wiley   +1 more source

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