检索结果-南通市图书馆

Deflagration characteristics of freely propagating flames in magnesium hydride dust clouds

Defence Technology（防务技术） 2024年第1期31卷 471-483页

作者： Qiwei Zhang Yangfan Cheng Beibei Zhang danyi li Zhaowu Shen School of Chemical Engineering Anhui University of Science and TechnologyHuainan 232001AnhuiPR China School of Civil Engineering and Architecture Anhui University of Science and TechnologyHuainan 232001AnhuiPR China Anhui Engineering Laboratory of Explosive Materials and Technology Anhui University of Science and TechnologyHuainan 232001AnhuiPR China School of Engineering Science University of Science and Technology of ChinaHefei 230027AnhuiPR China

The flame propagation processes of MgH_(2)dust clouds with four different particle sizes were recorded by a high-speed camera.The dynamic flame temperature distributions of MgH_(2)dust clouds were reconstructed by the two-color pyrometer technique,and the chemical composition of solid combustion residues were analyzed.The experimental results showed that the average flame propagation velocities of 23μm,40μm,60μm and 103μm MgH_(2)dust clouds in the stable propagation stage were 3.7 m/s,2.8 m/s,2.1 m/s and 0.9 m/s,respectively.The dust clouds with smaller particle sizes had faster flame propagation velocity and stronger oscillation intensity,and their flame temperature distributions were more even and the temperature gradients were smaller.The flame structures of MgH_(2)dust clouds were significantly affected by the particle sinking velocity,and the combustion processes were accompanied by micro-explosion of particles.The falling velocities of 23μm and 40μm MgH_(2)particles were 2.24 cm/s and 6.71 cm/s,respectively.While the falling velocities of 60μm and 103μm MgH_(2)particles were as high as 15.07 cm/s and 44.42 cm/s,respectively,leading to a more rapid downward development and irregular shape of the flame.Furthermore,the dehydrogenation reaction had a significant effect on the combustion performance of MgH_(2)dust.The combustion of H_(2)enhanced the ignition and combustion characteristics of MgH_(2)dust,resulting in a much higher explosion power than the pure Mg dust.The micro-structure characteristics and combustion residues composition analysis of MgH_(2)dust indicated that the combustion control mechanism of MgH_(2)dust flame was mainly the heterogeneous reaction,which was affected by the dehydrogenation reaction.

关键词： Magnesium hydride dust Flame combustion mechanism Particle size Dust explosion Two-color pyrometer

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Missing microbes in infants and children in the COVID-19 pandemic:a study of 1,126 participants in Beijing,China

引用

Science China life Sciences 2024年第8期 1739-1750页

作者： Jiejing Wang Yuejuan li Yu Mu Kefei Huang danyi li Canhui Lan Yutao Cui Jun Wang CAS Key Lab for Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences University of Chinese Academy of Sciences Beijing Dr.CUIYUTAO Clinic R-Institute Co.Ltd.

The COVID-19 pandemic has caused many fatalities worldwide and continues to affect the health of the recovered patients in the form of long-COVID.In this study,we compared the gut microbiome of uninfected infants and children before the pandemic began(BEFORE cohort,n=906) to that of after the pandemic(AFTER cohort,n=220) to examine the potential impact of social distancing and life habit changes on infant/children gut microbiome.Based on 16S r RNA sequencing,we found a significant change in microbiome composition after the pandemic,with Bacteroides enterotype increasing to 35.45% from 30.46% before the pandemic.q PCR quantification indicated that the bacterial loads of seven keystone taxa decreased by 91.69%–19.58%.Quantitative microbiome profiling,used to enhance the resolution in detecting microbiome differences,revealed a greater explained variance of pandemic on microbiome compared to gender,as well as a significant decrease in bacterial loads in 15 of the 20 major genera.The random forest age-predictor indicated the gut microbiomes were less mature in the after-pandemic cohort than in the before-pandemic cohort in the children group(3–12 years old) and had features of a significantly younger age(average of 1.86 years).Lastly,body weight and height were significantly lower in the after-pandemic cohort than in the before-pandemic cohort in infants(<1 year of age),which was associated with a decrease in bacterial loads in the fecal microbiome.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Strategies for the development and approval of COVID-19 vaccines and therapeutics in the post-pandemic period

引用

Signal Transduction and Targeted Therapy 2024年第1期9卷 19-35页

作者： danyi Ao Xuemei He Jian liu li Xu State Key Laboratory of Biotherapy West China HospitalSichuan University610041 SichuanPeople’s Republic of China

The spread of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has resulted in significant casualties and put immense strain on public health systems worldwide,leading to economic recession and social unrest.In response,various prevention and control strategies have been implemented globally,including vaccine and drug development and the promotion of preventive measures.Implementing these strategies has effectively curbed the transmission of the virus,reduced infection rates,and gradually restored normal social and economic activities.However,the mutations of SARS-CoV-2 have led to inevitable infections and reinfections,and the number of deaths continues to rise.Therefore,there is still a need to improve existing prevention and control strategies,mainly focusing on developing novel vaccines and drugs,expediting medical authorization processes,and keeping epidemic surveillance.These measures are crucial to combat the Coronavirus disease(COVID-19)pandemic and achieve sustained,long-term prevention,management,and disease control.Here,we summarized the characteristics of existing COVID-19 vaccines and drugs and suggested potential future directions for their development.Furthermore,we discussed the COVID-19-related policies implemented over the past years and presented some strategies for the future.

关键词： prevention sustained approval

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Microbiome research outlook:past,present,and future

引用

Protein & Cell 2023年第10期14卷 709-712页

作者： Yunyun Gao danyi li Yong-Xin liu Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China R-Institute Co.Ltd. Beijing 100011China

With its critical role in human health and disease,the microbiome has transformed modern biology.Over the past few years,microbiome research has evolved rapidly,with microbiologists gradually shifting their focus from cataloging microorganisms in the human microbiome to understanding their functional roles and how they interact with the host.Here,we present the global trends in microbiome research and summarize the past and current work on microbiome published in Protein&Cell.

关键词： shifting transformed outlook

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

人物形象、叙事话语和创新传播:新主流电影中的国家形象塑造与传播研究

引用

电影评介 2024年第4期 8-17页

作者：齐青李丹仪上海师范大学影视传媒学院

近年来,新主流电影这一类型及概念不断被提起,虽然目前新主流电影仍未有规范及明确化的定义,但学界和业界相关讨论层出不穷。新主流电影的前身主旋律电影常以革命或历史题材为主,弘扬国家主流意识形态和讴歌人性,而新主流电影是在主旋... 详细信息

近年来,新主流电影这一类型及概念不断被提起,虽然目前新主流电影仍未有规范及明确化的定义,但学界和业界相关讨论层出不穷。新主流电影的前身主旋律电影常以革命或历史题材为主,弘扬国家主流意识形态和讴歌人性,而新主流电影是在主旋律电影的审美基础上进一步拓展而来的一种类型范式。

关键词：主旋律电影新主流电影叙事话语创新传播类型范式历史题材审美基础人物形象

来源：

维普期刊数据库博看期刊

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Genomic evolution during locoregional recurrence in colorectal cancer determined by whole-exome sequencing: a retrospective observational study

引用

Journal of Bio-X Research 2022年第4期5卷 171-180页

作者： Xiaoliang Lan Xiaoxiao Wu Chao Zhang Genxia Wei Bingbing li Weihao Qiu danyi li Huanwen Wu Yanqing Ding Jie Yuan Zaixian Tai Zuoquan Yang Zhiyong liang Dan Su li liang Department of Pathology Nanfang Hospital and Basic Medical College Department of General Surgery&Guangdong Provincial Key Laboratory of Precision Medicine for Gastrointestinal Tumor Nanfang HospitalThe First School of Clinical MedicineSouthern Medical UniversityGuangzhouGuangdong Province Department of Pathology Cancer Hospital of the University of Chinese Academy of Sciences(Zhejiang Cancer Hospital) Institute of Basic and Cancer Medicine(IBMC) Chinese Academy of SciencesHangzhouZhejiang Province Geneplus-Shenzhen Shenzhen Huiqiao Medical Center Nanfang HospitalSouthern Medical UniversityGuangzhou Guangdong Province Key Laboratory of Molecular Tumor Pathology Guangzhou Department of Pathology Molecular Pathology Research CenterPeking Union Medical College HospitalChinese Academy of Medical ScienceBeijingChina

Objective:The genomic landscapes of metastatic colorectal cancer(mCRC)have been extensively studied;however,the genetic mechanisms underlying the locoregional recurrence(LR)of CRC remain unclear.The objective of our study was to investigate genomic evolution during LR in CRC using high-throughput sequencing.Methods:Twenty-three CRC patients with matched primary and LR tissues were recruited from Nanfang Hospital and Zhejiang Cancer Hospital between January 2011 and December 2018.The last date of follow-up was March 2020.Tissue samples were analyzed by whole-exome sequencing and the genomic profiles were depicted by single nucleotide variation,mutational signature,copy number variation,clonal architecture,and other features.The evolutionary process was speculated with comparison of the genetic variations between primary and LR lesions.The disseminating clusters from primary to LR lesions were identified by variant allele frequency dynamics.Furthermore,the early-recurrent biomarker was explored by comparing the indel signature between early-and late-recurrent patients.The study was approved by the Institutional Review Board of Nanfang Hospital of Southern Medical University(approval No.2020010)on September 11,2020.Results:The results highlighted distinct origins of LR between patients with high microsatellite instability and microsatellite stability.LR lesions evolved independently in patients with high microsatellite instability,while LR lesions were highly clonally related to the primary lesions in patients with microsatellite stability.Late-acquired variations in LR lesions encompassed a wide range of driver genes involved in histone methylation,DNA replication,T cell activation,PDCD1 gain,and LMNA loss.Furthermore,clonal analysis of the disseminating cells identified a dominant polyclonal seeding pattern during LR.The indel signature ID4 was associated with significantly shorter disease-free survival in patients with relapsed CRC according to a public dataset.Conclusion:These findings pose a challenge for the d

关键词： biomarker colorectal cancer locoregional recurrence polyclonal seeding tumor evolution

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Seven facts and five initiatives for gut microbiome research

引用

Protein & Cell 2020年第6期11卷 391-400页

作者： danyi li Chunhui Gao Faming Zhang Ruifu Yang Canhui Lan Yonghui Ma Jun Wang Beijing Rexinchang Biotechnology Research Institute Co.Ltd Beijing 100011China Medical Center for Digestive Diseases The Second Affiliated Hospital of Nanjing Medical UniversityNanjing 210011China Key Lab of Holistic Integrative Enterology Nanjing Medical UniversityNanjing 210011China Division of Microbiotherapy Sir Run Run Shaw HospitalNanjing Medical UniversityNanjing 211166China State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyBeijing 100071China Centre for Bioethics Medical CollegeXiamen UniversityXiamen 361102China CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of ScienceBeijing 100101China

The gut microbiome has attracted increasing attention over the past 15 years.Along with the fast-growing body of research literature and media reports,the public's opinions on the gut microbiome have begun to appear polarized.Some believe that the gut microbiome is at the core of human health and is related to every single disease.To the opposite,some people question the scientific basis of gut microbiome studies and criticize that many of them are farfetched;there is even a joke spreading in the biomedical research field—"keeping gut microbiome in mind,no mechanism is hard to find".

关键词： biome opposite gut

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

氧化石墨烯及其复合材料去除水体抗生素的研究进展

引用

生态环境学报 2024年第1期33卷 144-155页

作者：李丹怡黄显婷李继超李颖洁闫家普林慰北京师范大学自然科学高等研究院广东珠海519087 中国水产科学研究院南海水产研究所/农业农村部水产品加工重点实验室广东广州510300 北京师范大学珠海分校不动产学院广东珠海519087 聊城市政务服务综合受理中心山东聊城252000

由于具有优异的抗菌性,抗生素被广泛应用于医学领域和养殖行业。然而,近年来对抗生素大规模的使用和排放,在自然界造成了大量的累积,引发了一系列水环境污染问题,严重威胁生态系统安全和人类健康。因此,研发可去除水中过量抗生素的材料... 详细信息

由于具有优异的抗菌性,抗生素被广泛应用于医学领域和养殖行业。然而,近年来对抗生素大规模的使用和排放,在自然界造成了大量的累积,引发了一系列水环境污染问题,严重威胁生态系统安全和人类健康。因此,研发可去除水中过量抗生素的材料已成为当前环境领域的重要研究方向之一。氧化石墨烯(graphene oxide,GO)以其高比表面积、良好亲水性、耐酸碱性、制备简便、成本低廉等优势,成为了一种新兴的抗生素去除材料。该文首先概述了现有的GO及其复合材料分类制备方法,包括空间改造、共价键修饰和金属氧化物改性等。其次,综述了近年来GO及其复合材料在抗生素去除领域的应用、影响因素及作用机制。结果表明,基于吸附原理的GO复合材料吸附去除抗生素效果主要受溶液p H、共存离子、吸附剂投加量、抗生素类别及浓度等多种因素的影响,吸附机制主要包括静电相互作用、π-π相互作用、阳离子-π键作用和氢键作用等,通过引入元素、金属和有机化合物等手段可有效提高GO材料的吸附容量;基于光催化降解原理的抗生素去除过程中,光照条件是最重要影响因素,而其中关键活性物质包括光生空穴、羟基自由基和超氧自由基等,掺杂金属纳米粒子与半导体纳米材料等能够优化其光催化性能。最后,通过对GO及其复合材料制备过程、去除机理和应用场景的综合分析,指出其普适性不高、实际应用不足和环境毒性不明等现存问题,并提出未来应加强材料研发、产业应用和毒性效应评估等方面的研究展望。

关键词：氧化石墨烯复合材料抗生素吸附光催化降解去除机理

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

辽宁职业篮球发展的模式突破与路径创新研究

引用

辽宁体育科技 2024年第1期46卷 63-68页

作者：李旦宜程茂滕陈鸯鸯杨铄宁波大学体育学院浙江宁波315211 山西财经大学体育产业研究中心山西太原030006

在分析我国职业篮球基本运营模式和现实困境的基础上,从青训人才与院校人才结合、体制培养与市场流动结合、专业训练与社会影响结合三个角度分析辽宁职业篮球“院校—市场—社会”三位一体模式的优势。在此基础上,提出辽宁职业篮球未来... 详细信息

在分析我国职业篮球基本运营模式和现实困境的基础上,从青训人才与院校人才结合、体制培养与市场流动结合、专业训练与社会影响结合三个角度分析辽宁职业篮球“院校—市场—社会”三位一体模式的优势。在此基础上,提出辽宁职业篮球未来发展的创新路径:辽篮精神与文体强省的融合形成文化建设的体育符号,职业体育与一带一路的融合迈向对外开放的体育前沿,体育产业与振兴发展的融合构建产业转型的体育载体。

关键词：职业篮球辽宁体育模式突破发展创新

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

超高压辅助酶解对汉麻分离蛋白结构和抗氧化活性的影响

引用

食品工业科技 2024年第4期45卷 24-32页

作者：刘容旭王语聪刘金阳谢宜桐谢智鑫种正晨李世函刘丹怡韩建春黑龙江省绿色食品科学研究院黑龙江哈尔滨150028 东北农业大学食品学院黑龙江哈尔滨150030 中国储备粮管理集团有限公司黑龙江分公司黑龙江哈尔滨150006

本研究以汉麻分离蛋白(Hemp Protein Isolate,HPI)为原料,通过超高压辅助酶解反应对HPI进行改性,测定不同压力下汉麻蛋白酶解产物(hydrolysate of hemp protein isolate,HPIH)的聚丙烯酰胺凝胶电泳(SDS polyacrylamide gelelectrophoresis,SDS-PAGE)电泳特性、表面疏水性、巯基含量、傅立叶红外光谱和内源荧光光谱分析改性前后汉麻分离蛋白的结构变化。结果表明,超高压(ultra-high pressure,UHP)(0.1、100、200、300 MPa)处理对HPI酶解反应具有一定的辅助作用,且随压力的升高酶解反应程度逐渐增大,分子量逐渐降低;HPI经改性后,疏水性基团逐渐暴露,表面疏水性随压力的增大先上升后下降,且变化差异性显著(P<0.05),在200 MPa时表面疏水性达到最大;酶解反应后,HPIH游离巯基含量显著降低(P<0.05),而表面巯基含量随压力增大呈先上升后下降的趋势;通过测定改性前后蛋白质氨基酸组成及含量可知,改性前后HPI氨基酸组成不变,但各氨基酸含量存在不同程度下降;由傅立叶红外光谱图可以看出,与HPI相比,HPIH的吸收峰强度、峰型及峰面积等均发生不同程度变化,说明超高压辅助酶解反应使蛋白质二级结构发生改变;内源荧光光谱显示,HPIH荧光强度增大且最大发射波长发生红移,说明酶解反应改变了HPI的三级结构;抗氧化活性结果表明,适当的压力处理可有效提升酶解产物的抗氧化能力,当压力为200 MPa时,HPIH的DPPH、ABTS^(+)自由基清除能力及还原能力达到最高。综上所述,超高压辅助酶解改性处理能显著改变汉麻分离蛋白的二、三级结构,暴露出疏水基团等活性基团,从而提高其抗氧化性。

关键词：汉麻分离蛋白(HPI) 超高压(UHP) 结构抗氧化活性

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：