检索结果-南通市图书馆

Preparation methods and thermal stability of Ba-Mn-Ce oxide catalyst for NOx-assisted soot oxidation

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2011年第7期23卷 1205-1210页

作者： Xiaodong wu fan Lin Lei Wang Duan Weng Zhou Zhou Laboratory of Advanced Materials Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

Manganese oxide-loaded and -doped ceria as well as the corresponding barium-modified oxide catalysts were prepared for soot oxidation in the presence of NOx, and were characterized by using X-ray diffraction, Brunauer-Emmett-Teller and NO temperature- programmed oxidation measurements. The activity of catalyst depended strongly on the NO 2 production capacity, and the importance of surface nitrates was weakened without heat transfer limitations. The formation of perovskite-type oxides after the high-temperature calcination caused the loss of NOx storage capacity for the Ba-modified catalysts, but did not seem to affect the NO oxidation activity obviously. The addition of barium did not prevent the phase separation of MnOx-CeO 2 solid solutions, whereas it inhibited the sintering of oxide crystallites effectively. This, as well as the relatively high surface area, resulted in a small increase in soot oxidation temperature for the thermally aged Ba/Mn-Ce catalyst.

关键词： manganese oxide ceria barium soot oxidation NO 2 ageing

A survey on barrier coverage with sensors

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2016年第6期10卷 968-984页

作者： fan wu Yang GUI Zhibo WANG Xiaofeng GAO Guihai CHEN Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China School of Computer Wuhan University Wuhan 430072 China

For various applications, sensors are deployed to monitor belt regions to guarantee that every movement crossing a barrier of sensors will be detected in real-time with high accuracy and minimize the need for human support. The bartier coverage problem is introduced to model these requirements, and has been examined thoroughly in the past decades. In this survey, we state the problem definitions and systematically consider sensing models, design issues and challenges in barrier coverage problem. We also review representative algorithms in this survey. Furthermore, we provide discussions on some extensions and variants of barrier coverage problems.

关键词： sensor network barrier coverage

Interface microstructure and bond strength of 1420/7B04 composite sheets prepared by diffusion bonding

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2018年第7期37卷 613-620页

作者： fan wu Wen-Long Zhou Bing Zhao Hong-Liang Hou School of Materials Science and Engineering Dalian University of Technology Dalian 116023 China Beijing Aeronautical Manufacturing Technology Research Institute Beijing 100023 China Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Scienceand Engineering Dalian University of Technology Dalian 116085 China

The effect of temperature on interface microstructure and shear strength of 1420 A1-Li alloy and 7B04 A1 alloy composite plates prepared by diffusion bonding were investigated. The results indicate the optimum temperature for bonding the composite plates is 520℃, a sound bonding interface without continuous intermetallic compound layers and interfacial voids is obtained, and the shear strength value of bond joints can be as high as 190 MPa. An interfacial transition zone is formed due to the alloying elements mutual diffusion during the bonding process. Meanwhile, the effect of temperature on diffusion of alloying elements and interface reaction were discussed in detail, the results show that the higher temperature can increase the diffusion of alloying elements fluxes across the bonding interface, which can accelerate the closure of interfacial voids; meanwhile, when Mg atoms diffuse across the bonding interface, it can react with and break up the surface oxide films into discrete particles, and the removal of interface oxides increases the metal to metal bond areas and improves the bond quality.

关键词： Diffusion bonding Alloying elementsdiffusion Interface microstructure Shear strength

Ground state singlet-to-triplet conversion of copper corrole radical byβ-benzo-fusion

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2023年第8期34卷 412-415页

作者： fan wu Hu Gao Yue Zhao Zhen Shen State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced MicrostructuresSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Materials with facilely tunable spin configurations based on metal-radical coordination systems have potential applications for electronics and ***,we report the ground state conversion of copper corrole radicals from singlet to triplet via the extension of theπ-conjugation system by benzo-fusion at theβ-position of corrole *** spectroscopy,SQUID measurements and computational studies all support the ferromagnetic coupling between the Cu(II)center and corroleπ-radical of benzo-fused copper corrole 2-Cu,which is in sharp contrast with the antiferromagnetic coupling in regular non-extended copper *** triplet 2-Cu is highly stable in air,and X-ray diffraction analysis revealed its unique highly planar corrole *** work offers a promising strategy for creating high-spin systems in non-innocent metallocorroles.

关键词： Radicals Porphyrinoids Copper Ferromagnetic interaction Ring-fused systems

Fluorescent Silk Obtained by Feeding Silkworms with Fluorescent Materials

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2023年第16期41卷 2035-2046页

作者： Zhao-fan wu Zhao-Nan Sun Huan-Ming Xiong Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200438China

Comprehensive Summary Fluorescent silk has potential application in many fields such as bioimaging,tissue engineering scaffolds,luminescent marks,and dazzling *** the methods to endow natural silk with fluorescent properties,feeding silkworms with fluorescent additives is facile,low-cost and environment friendly,which has the prospect of large-scale *** this paper,we reviewed the research progress for this aim in the past ten years,and summarized the unified characteristics for the substances that can enter the silk gland by digestive tract of *** advantages and disadvantages of various fluorescent materials for this application are compared in *** the future research directions are suggested to overcome the shortcomings of the present research.

关键词： Fluorescent silk Fluorescent materials Feeding silkworms Carbon dots Nanoparticles Nanotechnology Multi-color emission Bioimaging

Understanding and identifying latent data races cross-thread interleaving

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

Frontiers of Computer Science 2015年第4期9卷 524-539页

作者： Long ZHEN~ Xiaofei LIAO Song wu Xuepeng fan Hai JIN Services Computing Technology and System Laboratory Cluster and Grid Computing Laboratory School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

Data races are ubiquitous in multi-threaded ap- plications, but they are by no means easy to detect. One of the most important reasons is the complexity of thread in- terleavings. A volume of research has been devoted to the interleaving-insensitive detection. However, all the previous work focuses on the uniform detection （unknown to the char- acteristics of thread interleavings）, thereby making the detec- tion defective in either reporting false positives or suffering from prohibitive overhead. To cope with the problem above, we propose an efficient, precise, and sound step-by-step res- olution based on the characteristics of thread interleavings. We first try to tease apart the categories of thread interleav- ings from the several typical sources arising from the lock synchronizations. We then conduct a brief study and find a new and complex pattern the previous work cannot detect. It is also revealed that the simple pattern with the majority of thread interleavings can be resolved by a simple processing to achieve a big profit for the previous reordering-based design. Our final experimental results demonstrate the effectiveness of our empiricism-based approach, and show that 51.0% of execution time and 52.3 % of trace size arising from the state- of-the-art reordering technique can be saved through a quick filtering of the simple pattern with a negligible （4.45%） per- formance overhead introduced on-the-fly.

关键词： data race happens-before thread interleaving

Oxidative aromatization of 3,5-disubstituted 2-isoxazolines by nitric oxide

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2007年第7期18卷 788-790页

作者： Rui Li Wen Tao wu Guai Li wu Yuan fan Long Min wu State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 China

3,5-Disubstituted 2-isoxazolines were oxidized to corresponding isoxazoles by nitric oxide in dichloromethane. The reaction more likely occurred via a one-electron transfer process.

关键词： 2-Isoxazolines Nitric oxide 2-Isoxazole Aromatization

Eliminating Explicit Contention from Channel Access in Distributed Wireless Networks

在线全文

学校读者我要写书评

暂无评论

China Communications 2019年第5期16卷 70-82页

作者： Aijing Li Chao Dong fan wu Shaojie Tang Guihai Chen Qihui wu Department of Computer Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Communications Engineering PLA Army Engineering UniversityNanjing 210007China College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China Department of Information Systems University of Texas at DallasTexas 75080USA

Emerging techniques such as WiFi direct makes the objective of always-on be true. People can easily chat and share files with nearby friends even without AP(Access Point) or cellular coverage. In this paper, we focus on the channel efficiency issue of APfree Wi-Fi networks, which can be easily constructed in the subway, in a high-speed railway, or when camping in the wild. Today IEEE 802.11 DCF is the most commonly used MAC protocol for Wi-Fi networks, however, due to the control messages and backoff time, channel efficiency in high data rate networks can be extremely low. To solve this, we propose CD-MAC, which allows control messages to be transmitted with data packets concurrently, and thus eliminates the overheads of backoff and explicit contention. To maintain the reception reliability, we redesign the control messages and use signal detection in PHY instead of bits decoding to detect them. In MAC layer, CD-MAC is built upon our Correlation Detection based PHY. We have implemented and evaluated CD-MAC using USRP N210. Evaluation results show that CD-MAC can achieve over 95.5% channel efficiency and provide throughput gains of up to 80%, 60%, and 29.1% compared with DCF, 802.11 ec, and back2F, respectively.

关键词： implicit contention correlation detection media access ad hoc networks OFDM USRP

Progress in thermal stability of all-solid-state-Li-ion-batteries

在线全文

学校读者我要写书评

暂无评论

InfoMat 2021年第8期3卷 827-853页

作者： Yujing wu Shuo Wang Hong Li Liquan Chen fan wu Tianmu Lake Institute of Advanced Energy Storage Technologies LiyangJiangsuChina Yangtze River Delta Physics Research Center LiyangJiangsuChina Key Laboratory for Renewable Energy Beijing Key Laboratory for New Energy Materials and DevicesBeijing National Laboratory for Condensed Matter PhysicsInstitute of PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina

Thermal safety is one of the major issues for lithium-ion batteries(LIBs)used in electric *** thermal runaway mechanism and process of LIBs have been extensively studied,but the thermal problems of LIBs remain intractable due to the flammability,volatility and corrosiveness of organic liquid *** ultimately solve the thermal problem,all-solid-state LIBs(ASSLIBs)are considered to be the most promising ***,research on the thermal stability of solid-state electrolytes(SEs)is still in its initial stage,and the thermal safety of ASSLIBs still needs further ***,the specified reviews summarizing the thermal stability of ASSLIBs and all types of SEs are still *** fill this gap,this review systematically discussed recent progress in the field of thermal properties investigation for ASSLIBs,form levels of materials and interface to the whole *** thermal properties of three major types of SEs,including polymer,oxide,and sulfide SEs are systematically reviewed *** review aims to provide a comprehensive understanding of the thermal stability of SEs for the benign development of ASSLIBs and their promising application under practical operating conditions.

关键词： interface safety solid-state battery solid-state electrolyte thermal stability