检索结果-南通市图书馆

Concept of radial slippage propagation triggering self-loosening and optimisation design of novel anti-loosening structures

在线全文

学校读者我要写书评

暂无评论

Friction 2023年第6期11卷 865-880页

作者： Hao GONG Jianhua LIU Huihua FENG jiayu huang Beijing Institute of Technology School of Mechanical EngineeringBeijing100081China

Self-loosening of bolted joints can occur in a vibration environment,and it may induce bolt fatigue fracture with catastrophic *** is essential to clarify the self-loosening mechanism,based on which novel anti-loosening thread structures can be *** this paper,we propose the concept of radial slippage propagation and provide new insights into the self-loosening *** new theory states that the slippage along the radial direction of the thread surface induces more slippage areas(slippage propagation),and self-loosening occurs due to the dynamic evolution and propagation of contact states on the thread and bearing surfaces with an increase in the number of vibration *** element analysis(FEA)was used to validate the propagation process of slippage areas on the thread surface.A novel bolted joint with step thread engagement was developed,which could prevent the occurrence of relative motion of the external and internal threads in the radial direction and thus block slippage propagation.A three-dimensional(3D)finite element model(FEM)of the novel thread structure was established,and a test specimen was manufactured using two special *** and experiments validated its superior anti-loosening and anti-fatigue performances,and the convenience of installation and *** validation of the radial slippage propagation theory and the performance optimisation of the step-thread structure should be performed in the future.

关键词： bolted joint self-loosening slippage propagation step thread transversal vibration

Active oxygen species and oxidation mechanism over Ce-doped LaMn_(0.8)Ni_(0.2)O_(3)/hierarchical ZSM-5 in pentanal oxidation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2021年第9期39卷 1062-1072页

作者： Jian Li Yingjie Shi Xiaoheng Fu Yun Shu jiayu huang Jinwei Zhu Gang Tian Jingnan Hu Research Center of Air Pollution Control Technology Chinese Research Academy of Environmental SciencesBeijing 100012China School of Chemical and Environmental Engineering China University of Mining and Technology(Beijing)Beijing 100083China

Hierarchical ZSM-5(HZ)molecular sieves based on fly ash were synthesized using a method combining water heat treatment with step-by-step *** coupling catalysts between La_(1-x)Ce_(x)Mn_(0.8)-Ni_(0.2)O_(3)(x≤0.5)perovskites and HZ were prepared through the impregnation method,which were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),high-resolution transmission electron microscopy(HRTEM),N_(2)adsorption,X-ray photoelectron spectroscopy(XPS),NH3-temperature programmed desoprtion(NH3-TPD),H_(2)-temperature programmed reduction(H_(2)-TPR)and O_(2)-TPD techniques and investigated regarding pentanal oxidation at 120-390℃to explore the effects of Ce doping on the catalytic activity and the active oxygen species of the coupling catalysts,meanwhile,the reaction mechanism and pathway of pentanal oxidation were also *** results reveal that Ce substitution at La sites can change the electronic interactions between all the elements and promote the electronic transfer among La,Ce,Ni,Mn and HZ,influencing directly the physicochemical characteristics of the ***,the amount and transfer ability of surface adsorbed oxygen(O_(2)-and O-)regarded as the reactive oxygen species and the low temperature reducibility are the main influence factors in pentanal ***,La_(0.8)Ce_(0.2)Mn_(0.8)Ni_(0.2)O_(3)/HZ exhibits the best catalytic activity and deep oxidation capacity as well as a better water resistance due to its larger amount of surface adsorbed oxygen species and higher low temperature ***’s more,appropriate Ce substitution can significantly enhance the amount of O_(2)-ions,which can distinctly enhance the catalytic activity of the catalyst,and moderate acid strength and appropriate acid amount can also facilitate the improvement of the pentanal oxidation *** is found that there is a synergic catalytic effect between surface acidity and redox ability of the *** to the in s

关键词： Hierarchical ZSM-5 molecular sieve Catalytic oxidation Active oxygen species Perovskite Ce doping Rare earths

Fe-N-C nanostick derived from 1D Fe-ZIFs for electrocatalytic oxygen reduction

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2023年第10期42卷 21-27页

作者： jiayu huang Kuan Chang Qi Liu Yameng Xie Zhijia Song Zhiping Zheng Qin Kuang State Key Laboratory of Physical Chemistry of Solid Surfaces&Department of Chemistry College of Chemistry and Chemical EngineeringXiamen UniversityXiamenFujian361005PR China

The slow oxygen reduction process at the cathode and the scarcity of platinum-based metals lead to limited applications in fuel cells and metal-air ***,transition metal and nitrogen co-doped carbon-based catalysts(M–N–C)are regarded as the most prospective non-precious metal catalysts for future fuel cell *** is verified theoretically and experimentally that the metal and nitrogen coordination structure is the main catalytic activity center of oxygen reduction reaction(ORR),so constructing M–N–C materials with high available surface area and structural stability is an effective way to accelerate ***,we deliberately synthesize a one-dimensional ZIF structure to fabricate one-dimensional porous Fe–N–C nanostick via two-step ***,the as-synthesized exhibited an outstanding ORR activity in alkaline medium(E_(1/2)of 0.928 V),as well as superior stability(only changed 7 mV after 10,000 cycles in alkaline medium).Our results show that the reduction of electrocatalyst dimensionality can promote mass transport and increase the accessibility of active sites,thus optimizing their performance in *** work is a good demonstration of the importance of a rational design of catalyst structure for efficient ORR.

关键词： Oxygen reduction reaction Metal-organic frameworks M-N-C catalysts Electrocatalysts

CeO2/TiO2 Monolith Catalyst for the Selective Catalytic Reduction of NOx with NH3： Influence of H2O and SO2

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2016年第3期32卷 461-467页

作者： ZHANG Fan TIAN Gang WANG Hongmei WANG Hongchang ZHANG Chen CUI Yutao huang jiayu SHU Yun Research Center of Air Pollution Control Technology Chinese Research Academy of Environmental Sciences Beo'ing 100012 P. R. China

The influences of H2O and SO2 on CeO2/TiO2 monolith catalyst for the selective catalytic reduction（SCR） of NOx with NH3 were investigated. In the absence of SO2, H2O inhibited the SCR activity, which might be ascribed to the competitive adsorption of H2O and reactants such as NH3 and/or NOx. SO2 could promote the SCR activity of CeO2/TiO2 monolith catalyst in the absence of H20, while in the presence of H20 it speeded the deactivation. During the SCR reaction in SO2-containing gases, Ce（Ⅲ） sulfate species formed on the catalyst surface, resulting in the en- hancement of Bronsted acidity. This played a significant role in the enhanced SCR activity. However, in the presence of both H2O and SO2, a large amount of ammonium-sulfate salts formed on the catalyst surface, which resulted in the blocking of catalyst pores and deactivated the catalyst. In addition, the NOx conversion was more sensitive to gas hourly space velocity in the presence of H20 than in the absence of H20. The relatively high space velocity would result in a higher formation rate of ammonium-sulfate salts on per unit catalyst in the presence of H2O and SO2, which caused obvious deactivation of Ce/TiO2 monolith catalyst.

关键词： CeO2/TiO2 catalyst Selective catalytic reduction(SCR) Sulfur dioxide Water

Simultaneous enhancement of cellular and humoral immunity by the lymph node-targeted cholesterolized TLR7 agonist liposomes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2024年第10期14卷 4577-4590页

作者： Dandan Wan Ziyi Bai Yu Zhang Li Chen Haiying Que Tianxia Lan Weiqi Hong jiayu huang Cai He Yuquan Wei Qiang Pu Xiawei Wei Laboratory of Aging Research and Cancer Drug Target State Key Laboratory of Biotherapy and Cancer CenterNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengdu 610041China Department of Thoracic Surgery National Frontier Center of Disease Molecular NetworkWest China HospitalSichuan UniversityChengdu 610041China

Toll-like receptor(TLR)agonists,as promising adjuvants and immunotherapeutic agents,have the potential to enhance immune responses and modulate antigen-dependent T-cell immune memory through activation of distinct signaling ***,their clinical application is hindered by uncontrolled systemic inflammatory ***,it is imperative to create a vaccine adjuvant for TLR receptors that ensures both safety and *** this study,we designed lymph node-targeted cholesterolized TLR7 agonist cationic liposomes(1V209-Cho-Lip^(+))to mitigate undesired side ***-delivery of the model antigen OVA and cholesterolized TLR7 agonist facilitated DC maturation through TLR activation while ensuring optimal presentation of the antigen to CD8^(+)T *** main aim of the present study is to evaluate the adjuvant effectiveness of 1V209-Cho-Lip^(+)in tumor *** immunization with 1V209-Cho-Lip^(+)+OVA,we observed a pronounced"depot effect"and enhanced trafficking to secondary lymphoid *** vaccination with 1V209-Cho-Lip^(+)^(+)OVA significantly delays tumor development,prolongs mouse survival,and establishes durable immunity against tumor ***,1V209-Cho-Lip^(+)+OVA,while used therapeutic tumor vaccine,has demonstrated its efficacy in inhibiting tumor progression,and when combined with anti-PD-1,it further enhances antitumor ***,the co-delivery of antigen and lymph node-targeted cholesterolized TLR7 agonist shows great promise as a cancer vaccine.

关键词： TLR7 agonist Cationic liposomes Lymph node Cancer nanovaccines Immunotherapy Cross-presentation Cellular immunity Humoral immunity

Predicting tremor improvement after MRgFUS thalamotomy in essential tremor from preoperative spontaneous brain activity:A machine learning approach

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science Bulletin 2024年第19期69卷 3098-3105页

作者： Dong Zhang Yongqin Xiong Haoxuan Lu Caohui Duan jiayu huang Yan Li Xiangbing Bian Dekang Zhang Jiayou Zhou Longsheng Pan Xin Lou Department of Radiology The First Medical CenterChinese PLA General HospitalBeijing 100853China Department of Neurosurgery The First Medical CenterChinese PLA General HospitalBeijing 100853China

Magnetic resonance-guided focused ultrasound surgery(MRgFUS)thalamotomy is an emerging technique for medication-refractory essential tremor(ET),but with variable *** study used pattern regression analysis to identify brain signatures predictive of tremor ***-four ET patients(mean age=63.06 years,standard deviation(SD)=10.55 years,38 males)underwent unilateral MRg FUS thalamotomy and were scanned for resting-state functional magnetic resonance imaging(rsf MRI).Seventy-four healthy controls(mean age=58.09 years,SD=10.30 years,38 males)were recruited for *** responses at 12 months posttreatment were evaluated by the Clinical Rating Scale for *** fractional amplitude of low-frequency fluctuations(f ALFF)was calculated from rs-f MRI ***-sample t-test was used to generate a disease-specific mask,within which Multivariate Kernel Ridge Regression analyses were *** and actual clinical scores were compared using Pearson's correlation coefficient(r)and normalized mean squared error(***).Permutation test and leave-one-out strategy were applied for results *** identified f ALFF patterns that significantly predicted the hand tremor improvement(r=0.23,P=0.025;***=0.05,P=0.026)and the postural tremor improvement(r=0.28,P=0.025;***=0.06,P=0.023),but not action tremor *** VI of right cerebellum(Cerebelum_6_R),right superior occipital gyrus(Occipital_Sup_R)and lobule X of vermis(Vermis_10)contributed most for hand tremor prediction(normalized weights(NW):2.77%,2.40%,2.34%)while Vermis_10,left supplementary motor area(Supp_Motor_Area_L)and right hippocampus(Hippocampus_R)for postural tremor prediction(NW:2.69%,2.12%,2.05%).The low contributing NW of the individual brain regions suggested that the f ALFF pattern as a whole is an overall predicting *** f ALFF pattern predicts tremor benefits induced by MRg FUS *** *** number:NCT04570046.

关键词： MRgFUS Essential tremor fALFF Machine learning

Estimation of interannual trends of ammonia emissions from agriculture in Jiangsu Province from 2000 to 2017

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Atmospheric and Oceanic Science Letters 2020年第3期13卷 268-273页

作者： huang jiayu XIONG Ruonan FANG Li LI Tianling SHEN Weishou Collaborative Innovation Centre of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution ControlSchool of Environmental Science and EngineeringNanjing University of Information Science&TechnologyNanjingJiangsuChina

As the only alkaline gas in the atmosphere,ammonia could react with sulfur dioxide and nitrogen oxides to form the secondary particles.A large amount of NH3 in the atmosphere accelerates the rate of formation of fine particles;it therefore plays an important role in haze *** and poultry farming and nitrogen fertilizer application are the two main NH3 emission *** Province contributes the largest proportion of NH3 emissions from agriculture in key areas of national air pollution control in *** aims of this study are to investigate NH3 emissions from agriculture in Jiangsu Province using the emissions factor method,and analyze and summarize the characteristics and trends of NH3 emissions from 2000 to *** show that the NH3 emissions from agriculture in Jiangsu Province from 2000 to 2017 were mainly contributed by livestock and poultry farming(78.08%)and nitrogen fertilizer application(21.92%).Furthermore,a general fluctuation trend of an initial decrease and then an increase,of NH3 emissions from agriculture,could be found from 2000 to 2012,with minimum NH3 emissions in 2007(708.76 kt yr−1)and maximum emissions in 2012(837.64 kt yr−1);and then a decreasing trend was apparent from 2012(837.64 kt yr−1)to 2017(690.64 kt yr−1).A detailed estimation of the interannual trends and potential measures are also *** study provides a solid theoretical foundation for the development of NH3 emissions control in Jiangsu Province.

关键词： Agricultural source ammonia emissions livestock and poultry farming nitrogen fertilizer application

在线全文

学校读者我要写书评

暂无评论

认知主义的哲学思想渊源

浙江师范大学学报（社会科学版） 2016年第2期41卷 38-42页

作者：黄家裕浙江师范大学法政学院浙江金华321004

近代唯物主义用机器模型说明人的认知,并提出心灵具有符号性与可计算性的思想。随着人工智能的发展,学界把心灵类比图灵机,认为心灵是一个由符号构成的表征系统,心灵的运作过程犹如计算机的运作过程,因此,认知就是操作心理层面的符号。... 详细信息

近代唯物主义用机器模型说明人的认知,并提出心灵具有符号性与可计算性的思想。随着人工智能的发展,学界把心灵类比图灵机,认为心灵是一个由符号构成的表征系统,心灵的运作过程犹如计算机的运作过程,因此,认知就是操作心理层面的符号。由此可知,认知主义的思想是基于近代符号和计算的思想发展形成的,可以说认知主义是近代唯物主义认知思想在自然科学领域发展的结果。

关键词：认知主义唯物主义认识论符号

《福建师范大学学报(自然科学版)》50篇高被引论文分析

在线全文

学校读者我要写书评

暂无评论

福建师范大学学报（自然科学版） 2020年第4期36卷 112-116页

作者：黄家瑜福建师范大学学报编辑部福建福州350117

应用文献计量学的方法,对《福建师范大学学报(自然科学版)》50篇高被引论文的发表年份分布、总被引频次、逐年被引频次分析、学科分布、基金论文比例、出版时滞、作者概况进行统计分析.研究结果表明:高被引论文的逐年被引频次分布曲线... 详细信息

应用文献计量学的方法,对《福建师范大学学报(自然科学版)》50篇高被引论文的发表年份分布、总被引频次、逐年被引频次分析、学科分布、基金论文比例、出版时滞、作者概况进行统计分析.研究结果表明:高被引论文的逐年被引频次分布曲线呈现中间高两极低的正态分布,第7年达到高峰(5.5篇);高被引论文主要集中在地理(19篇)和生物学科(16篇);单篇最高被引频次195次,篇均被引69.1次;基金论文比为56%,出版时滞272 d;第1作者为中级职称的比例最高,占44%,校外作者占2%.

关键词：《福建师范大学学报(自然科学版)》高被引论文作者分析学科分布总被引频次