检索结果-南通市图书馆

Highly oriented MXene/polyvinyl alcohol films prepared by scalable layer-by-layer blade coating for efficient electromagnetic interference shielding and infrared stealth

引用

Nano Research 2024年第6期17卷 5651-5660页

作者： Jingyu Dong Zhaoyang li Congqi liu Bing Zhou Chuntai liu uezhan Feng State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentNational Engineering Research Center for Advanced Polymer Processing TechnologyZhengzhou UniversityZhengzhou 450002China Shangqiu Normal University Shangqiu 476000China

Controlling the orientation of two-dimensional MXene within layered films is essential to optimize or tune their mechanical properties and electromagnetic interference shielding(EMI)performance,but achieving the high orientation MXene layers on an industrial scale remains a challenging *** this paper,a scalable layer-by-layer blade coating(LbLBC)method was employed to fabricate highly oriented MXene/polyvinyl alcohol(PVA)*** the LbLBC process,MXene/PVA colloid suffered a strong shearing effect,which induced the ordered alignment of MXene nanosheets along the direction of the blade *** orientation of MXene can be effectively adjusted by changing the scraping gap of LbLBC,achieving a maximum Herman orientation factor f of *** a result,the mechanical properties and EMI performance of the as-prepared MXene/PVA films are in direct proportion to their orientation,with the optimal values of tensile strength of 145.5 MPa,fracture strain of 19.6%,toughness of 17.7 MJ·m^(−3),and EMI shielding effectiveness of 36.7 ***,the inherently low mid-infrared(mid-IR)emissivity of MXene,combined with the densely oriented structure affords the composite films with IR stealth,resulting in a substantial decrease from 150 to 66.1℃in the radiative temperature of a ***,these scalable MXene/PVA films exhibit remarkable potential for integration into the next generation of multifunctional protective camouflage materials.

关键词： MXene nanosheets densely oriented structure layer-by-layer blade coating electromagnetic interference shielding infrared stealth

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

基于多维度频谱图的钢琴音频信号识别算法

引用

自动化技术与应用 2024年第3期43卷 169-171,176页

作者：李亚昂云南经济管理学院教育学院云南昆明650106

常用的钢琴音频信号识别算法计算代价过高,为此,提出基于多维度频谱图的钢琴音频信号识别算法。选取某一钢琴选段作为识别目标,检测音频信号获得多维度频谱图,针对频谱图简化特征向量矩阵,提取频谱序列作为输入样本,完成目标音频信号识... 详细信息

常用的钢琴音频信号识别算法计算代价过高,为此,提出基于多维度频谱图的钢琴音频信号识别算法。选取某一钢琴选段作为识别目标,检测音频信号获得多维度频谱图,针对频谱图简化特征向量矩阵,提取频谱序列作为输入样本,完成目标音频信号识别。实验结果表明:所设计算法的音符基频计算偏差在1%以内,音频信号特征维度压缩水平和BER指数高,整体计算代价小。

关键词：多维度频谱图钢琴音频信号信号识别二分类模型

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

A grapefruit microstructure fiber temperature sensor coated with liquid crystal based on waist-enlarged taper

引用

Optoelectronics Letters 2024年第3期20卷 142-146页

作者： WANG Feng li Jiaxuan ZHANG Rongjing FU Xinghu College of Mechanical and Electrical Engineering Hebei Normal University of Science&TechnologyQinhuangdao 066004China School of Information Science and Engineering Key Laboratory for Special Fiber and Fiber Sensor of Hebei ProvinceYanshan UniversityQinhuangdao 066004China

In this paper, a grapefruit microstructure fiber(GMF) temperature sensor coated with liquid crystal(LC) based on waist-enlarged taper is proposed and fabricated, and its temperature sensing characteristics are analyzed. The waist-enlarged taper is formed at the fusion point between single mode fiber(SMF) and GMF. The capillary glass tube is sleeved outside GMF, LC is filled into the capillary glass tube, and its two ends are finally sealed to form a sensor. The experimental results show that when the length of GMF is 2.5 cm, the temperature sensitivity of the sensor can reach up to 195.3 pm/℃ in the range of 30-90℃, and it has a good stability for reuse. Thereby, it can be used in biochemical, industrial production and other temperature detection areas.

关键词： capillary fiber microstructure

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

When Glanzmann thrombasthenia encounters antithrombin defi ciency: how do we balance the risk and benefi t of antithrombotic therapy?

引用

World Journal of Emergency Medicine 2024年第1期15卷 67-69页

作者： Yu Wang Zhihao liu Haoyu Weng Jianping li Department of Endocrinology Peking University First HospitalBeijing 100034China Department of Cardiology Peking University First HospitalBeijing 100034China Key Laboratory of Molecular Cardiovascular Sciences of Ministry of Education Health Science CenterPeking UniversityBeijing 100034China

Glanzmann’s thrombasthenia(GT)is an inherited autosomal recessive bleeding disorder,resulting from mutations in the ITGA2B and ITGB3 genes,that lead to a defect in the platelet membrane integrinαIIbβ3.[1]As integrinαIIbβ3 plays an important role in thrombus formation,the clinical manifestation of GT includes bleeding(mostly mucocutaneous)and *** this reason,patients with GT are typically thought to be unlikely to suffer from thromboembolic *** is an anticoagulant that inhibits thrombin and is activated factor X and other serine proteases in the coagulation cascade.[2]Antithrombin deficiency is an autosomal dominant hereditary disease with an approximate prevalence of 1/500 in the overall population.[3]In contrast to the hemorrhagic tendency of GT,patients with antithrombin deficiency are at increased risk of thromboembolism,especially in the venous ***,we describe a rare case of GT and antithrombin deficiency coexisting in a single *** was used for the treatment of pulmonary embolism(PE)and deep vein thrombosis(DVT).

关键词： thrombin throm bleeding

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

Synthetic auxotrophs accelerate cell factory development through growth-coupled models

引用

Frontiers of Chemical Science and Engineering 2024年第9期18卷 73-87页

作者： liangpo li linwei Yu Xinxiao Sun Qipeng Yuan Xiaolin Shen Jia Wang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

The engineering of microbial cell factories for the production of high-value chemicals from renewable resources presents several challenges,including the optimization of key enzymes,pathway fluxes and metabolic *** these challenges involves the development of synthetic auxotrophs,a strategy that links cell growth with enzyme properties or biosynthetic *** linkage allows for the improvement of enzyme properties by in vivo directed enzyme evolution,the enhancement of metabolic pathway fluxes under growth pressure,and remodeling of metabolic networks through directed strain *** advantage of employing synthetic auxotrophs lies in the power of growth-coupled selection,which is not only high-throughput but also labor-saving,greatly simplifying the development of both strains and *** auxotrophs play a pivotal role in advancing microbial cell factories,offering benefits from enzyme optimization to the manipulation of metabolic networks within single ***,this strategy extends to coculture systems,enabling collaboration within microbial *** review highlights the recently developed applications of synthetic auxotrophs as microbial cell factories,and discusses future perspectives,aiming to provide a practical guide for growth-coupled models to produce value-added chemicals as part of a sustainable biorefinery.

关键词： synthetic auxotrophs growth-coupled directed enzyme evolution pathway flux directed strain evolution coculture

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

Plasma characteristics and material erosion mechanism in multi-channel wire electrical discharge machining

引用

Chinese Journal of Aeronautics 2024年第10期37卷 508-525页

作者： Guokang SU Chuanyun ZHANG Junfei li Xiaolei CHEN Guixian liU Yongjun ZHANG State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006China Guangdong Key Laboratory of Advanced Manufacturing Technology of Marine Energy Equipment Guangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory of Nontraditional Machining Technology and Equipment Guangdong University of TechnologyGuangzhou 510006China School of Mechanical Engineering Xi’an Technological UniversityXi’an 710021China

Multi-channel wire electrical discharge machining(MC-WEDM)is an advanced and high-efficiency machining technology,but its material erosion mechanism remains *** this study,dual-channel wire electrical discharge machining was utilized as a case study to investigate the impact of the plunging current on both the plasma characteristics and material erosion under complex discharge *** analysis was conducted on the charged particles in the plasma,revealing that the plunging current can influence the trajectory of the plasma by modifying the selfmagnetic *** particle tracking method was employed to simulate the motion of electrons,revealing that in MC-WEDM,electrons exhibited a larger and more uniform *** evolution of the plasma within a single-pulse discharge was observed using high-speed photography technology,and the discharge signals collected from different channels were *** was observed that the plasma in MC-WEDM experienced more intense back-and-forth sweeping on the workpiece surface,facilitating the ejection of molten metal from the molten *** oscillating plasma exhibits a larger processing area and a more uniform distribution of energy,resulting in the formation of larger and shallower discharge ***,the influence of the amplitude and time point of the plunging current on the volume and area of the discharge craters was ***,MC-WEDM significantly reduced the occurrence of holes and micro-cracks and exhibited a thinner recast layer in the continuous discharge experiment.

关键词： Multi-channel WEDM Discharge observation Plunging current Plasma characteristics Material erosion Discharge crater

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

Polycomb and trithorax:Their yin-yang dynamics in plants

引用

Molecular Plant 2024年第6期17卷 845-847页

作者： Fan Xu Daolei Zhang liang Le li Pu Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China School of life Science Inner Mongolia UniversityHohhot 010021China

Polycomb(PcG)and trithorax(trxG)are two groups of conserved epigenetic complexes that maintain active and repressive states of target genes by altering their chromatin states to regulate plant development and stress *... 详细信息

关键词： maintain complexes states

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

How interfacial electron-donating defects influence the structure and charge of gold nanoparticles on TiO_(2)support

引用

Nano Research 2024年第7期17卷 5965-5974页

作者： Guang-Jie Xia Yu Fu Wei Cao Jun li yang-Gang Wang Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and TechnologyShenzhen 518055China School of Physical Sciences Great Bay UniversityDongguan 523000China Department of Chemistry Tsinghua UniversityBeijing 100084China

The reduction degree of TiO_(2)support is critical to the performances of metal *** many previous theoretical calculations,only the bridge oxygen vacancy(Ov)was considered as the electron-donating defect on reduced rutile TiO_(2)(r-TiO_(2−x))***,titanium adatoms(Tiad.),oxidized titanium islands(***),and acid hydroxyls(ObrH)also exist at the metal/support *** conducting density functional theory(DFT)calculations and ab initio molecular dynamics(AIMD)simulations,we compared r-TiO_(2−x)surfaces with Ov,Tiad.,***,and ObrH sites loaded with Au nanoparticles(NPs).The results showed the Au NPs were oxygen-phobic but titanium-philic,resulting in wetting of Ov and *** short contact with *** and *** Bader charges of Au NPs(QM)showed a good linear relationship with the ideal number of donating electrons(Ne)from the defective sites(QM=−KeNe+QM,S),demonstrating the intrinsic electron allocation at the *** Ov,Tiad.,and *** exhibited similar slopes(Ke),relatively steeper than that of *** means in the scope of Au NP charge state,the *** *** have a close electron-donating ability with Ov,but the ObrH donates relatively fewer *** linear relationship can be extended approximately to other *** higher the metal work function,the steeper the Ke for easier electron donation from defective *** stronger the metal oxygen affinity,the more positive the intercept(QM,S).That explains the easy generation of metallic or negative Pt and Au NPs on r-TiO_(2−x),but hard for Cu and Zn in *** provides theoretical guidance for regulating the charge of metal NPs over TiO_(2−x)supports.

关键词： metal-support interaction titanium oxide oxygen vacancy surface hydroxyl titanium adatom

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

Anthropogenic mineral generation and its potential resource supply:The case of niobium

引用

Science China Earth Sciences 2024年第8期67卷 2583-2591页

作者： Xianlai ZENG Moisés Gómez Mahmoud BAKRY Yong geNG Jinhui li School of Environment Tsinghua UniversityBeijing 100084China School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of International and Public Affairs Shanghai Jiao Tong UniversityShanghai 200030China

The strategy of carbon neutrality is reshaping the global landscape of resource flow and *** the final sink of geological minerals,the proliferated anthropogenic minerals,also called secondary resources,play an increasingly important role in resource supply *** is a critical metal that lacks full concern for its *** fundamental principle of niobium circularity is to recycle and maintain the material as close to the manufacturing process as *** we estimate the niobium-containing applications lost at their end-of-life,underscoring the imperative to minimize such ***,we elucidate the extraction processes for scrap and alloy quantities throughout the industry's *** from anticipated waste generated by the majority of niobium applications,a forecast indicates a potential loss of approximately 168 kt by 2090 in the absence of ***,with a recycling efficiency of 90%for niobium,the projected loss diminishes to approximately 16 *** delve into the significance of niobium's circular economy and explore various aspects that demand further investigation for a seamless transition from linear to circular practices.

关键词： Niobium Anthropogenic mineral Circular economy Recycling Sustainability

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

非插入式液压智能分控技术研究与应用

引用

西南石油大学学报（自然科学版） 2024年第3期46卷 109-116页

作者：葛嵩袁辉于志刚李新妍中海石油(中国)有限公司湛江分公司广东湛江524007 中海油能源发展股份有限公司工程技术深水钻采技术公司广东湛江524007

注水调配是油田实现注水井有效注水的重要手段。目前,涠洲海域多采用裸眼射孔完井,注水管柱为桥式偏心管柱或同心集成管柱,注水层位平均4~6层。井眼轨迹复杂,狗腿度大,需要依靠钢丝作业投捞水嘴完成调配,作业难度大、时间长、成功率偏低... 详细信息

注水调配是油田实现注水井有效注水的重要手段。目前,涠洲海域多采用裸眼射孔完井,注水管柱为桥式偏心管柱或同心集成管柱,注水层位平均4~6层。井眼轨迹复杂,狗腿度大,需要依靠钢丝作业投捞水嘴完成调配,作业难度大、时间长、成功率偏低,且占用井口影响高产井作业。为提高智能化和精细化,设计了非插入式液压分控注水管柱以及配套的液压控制智能注水工具,可依靠地面控制系统完成地面智能在线测调。建立配水器水嘴模型,通过实验确定摩擦系数,精确描述流量压力关系,提高分注精度。通过管柱设计和管柱摩阻计算,在涠洲6-13油田A6井进行了非插入式液压智能分控技术应用,实现了液压精细分控,突破了温度高、井眼轨迹复杂、井深大的应用难题,测调效率提高了90%,分注精度达到油藏指标的95%。

关键词：水嘴优化智能注水涠洲油田液压分控测调效率

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：