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Preparation of Self-limiting Heating Cables with Excellent Processability, Mechanical Properties and PTC Effect via Thermal and Electrical Treatments

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Chinese Journal of Polymer Science 2024年第4期42卷 511-520页

作者： Tian-Hao Yang Tong wu Qiang fu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu610065China

Polymer/conductive filler composites have been widely used for the preparation of self-limiting heating cables with the positive temperature coefficient (PTC) effect. The control of conductive filler distribution and network in polymer matrix is the most critical for performance of PTC materials. In order to compensate for the destruction of the filler network structure caused by strong shearing during processing, an excessive conductive filler content is usually added into the polymer matrix, which in turn sacrifices its processability and mechanical properties. In this work, a facile post-treatment of the as-extruded cable, including thermal and electrical treatment to produce high-density polyethylene (HDPE)/carbon black (CB) cable with excellent PTC effect, is developed. It is found for the as-extruded sample, the strong shearing makes the CB particles disperse uniformly in HDPE matrix, and 25 wt% CB is needed for the formation of conductive paths. For the thermal-treated sample, a gradually aggregated CB filler structure is observed, which leads to the improvement of PTC effect and the notable reduction of CB content to 20 wt%. It is very interesting to see that for the sample with combined thermal and electrical treatment, CB particles are agglomerated and oriented along the electric field direction to create substantial conductive paths, which leads to a further decrease of CB content down to 15 wt%. In this way, self-limiting heating cables with excellent processability, mechanical properties and PTC effect have simultaneously been achieved.

关键词： Self-limiting heating cables Positive temperature coefficient Thermal treatment Electrical treatment

Network pharmacology: A new approach to unveiling Traditional Chinese Medicine

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Chinese Journal of Natural Medicines 2015年第1期13卷 1-2页

作者： wu Xiao-Ming wu Chun-fu School of Pharmacy China Pharmaceutical Uninersity School of Life Science and Biopharmaceutics Shenyang Pharmaceutical University

Traditional Chinese medicine(TCM)has thousandsyears of history in using herbal formulae(fang-Ji in Chinese)that consist of many medicinal herbs for holistic treatment of various *** to the complex nature rooted in bot... 详细信息

关键词：传统医药药理学网络中国药物发现生物制药生物医学生物系统

Cu/Pd-catalyzed borocarbonylative trifunctionalization of alkynes and allenes:synthesis ofβ-geminal-diboryl ketones

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Science China Chemistry 2021年第12期64卷 2142-2153页

作者： Yang Yuan fu-Peng wu Anke Spannenberg Xiao-Feng wu Leibniz-Institut für Katalyse e.V.an der Universität Rostock Albert-Einstein-Straβe 29a18059RostockGermany Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China

functionalized bisboryl compounds have recently emerged as a new class of synthetically useful building blocks in organic ***,we report an efficient strategy to synthesizeβ-geminal-diboryl ketones enabled by a Cu/Pd-catalyzed borocarbonylative trifunctionalization of readily available alkynes and *** reaction promises to be a useful method for the synthesis of functionalizedβ-geminal-diboryl ketones with broad functional group *** studies suggest that the reaction proceeds through borocarbonylation/hydroboration cascade of both alkynes and allenes.

关键词： carbonylation copper/palladium alkynes/allenes trifunctionalization β-geminal-diboryl ketones

Multi-Resources Management in 6G-Oriented Terrestrial-Satellite Network

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China Communications 2021年第9期18卷 24-36页

作者： Shu fu Bibo wu Shaohua wu fang fang College of Microelectronics and Communication Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Space Information Network and Intelligent Information fusion Chongqing UniversityChongqing 400044China Communication Engineering Research Centre Harbin Institute of Technology(Shenzhen)Guangdong 518055China Peng Cheng Laboratory Shenzhen 518055China Department of Engineering Durham UniversityDurham DH13LEU.K

The six-generation(6G)wireless network is expected to satisfy the requirements of ubiquitous connectivity and intelligent *** networks(TSN)enable seamless coverage for terrestrial users in a wide area,making it very promising in *** data traffic in TSNs surges,the integrated management for caching,computing,and communication(3C)has attracted much research *** this paper,we investigate the multi-resource management in the uplink and downlink transmission of TSN,*** particularly,we aim to guarantee both throughput fairness and data security in the uplink transmission of *** the intermittent communication of the satellite,we introduce two kinds of relays,i.e.,terrestrial relays(TRs)and aerial relays(ARs)to improve the system throughput performance in the downlink transmission of ***,we study a specific case of TSN with the uplink and downlink transmission,and the corresponding simulation results validate the effectiveness of our proposed schemes.

关键词： downlink transmission multi-resource management relay terrestrial-satellite networks up-link transmission

CO observations towards a sample of nearby galaxies

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Research in Astronomy and Astrophysics 2015年第6期15卷 785-801页

作者： fa-Cheng Li Yuan-Wei wu Ye Xu Purple Mountain Observatory & Key Laboratory for Radio Astronomy Chinese Academy of Sciences University of Chinese Academy of Sciences

We have simultaneously observed 12CO, laCO and clSo （J = 1 - 0） rotational transitions in the centers of a sample of 58 nearby spiral galaxies using the 13.7-m millimeter-wave telescope administered by Purple Mountain Observatory. Forty-two galaxies were detected in 13CO emission, but there was a null detection for C180 emission with a cr upper limit of 2 mK. The central beam ratios, R, of 12CO and 13CO range mostly from 5 to 13, with an average value of 8.1 ±4.2, which is slightly lower than previous estimates for normal galaxies. Clear correlations are found between ^12CO and ^13CO luminosities. An average X factor of 1.44± 0.84 × 10^20 cm^-2 （K km s-l）-1 is slightly lower than that in the Milky Way.

关键词： galaxies: ISM -- molecules galaxies -- millimeter lines ISM -- star formation ISM

Asymptotic Behaviors of a Size-structured Population Model

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Acta Mathematicae Applicatae Sinica 2017年第4期33卷 1025-1042页

作者： Xian-long fu Qiong wu Department of Mathematics Shanghai Key Laboratory of PMMP East China Normal University Shanghai 200241 China

In this paper we devote ourselves to the study of the asymptotic behavior of a size-structured pop- ulation dynamics with random diffusion and delayed birth process. Within a semigroup framework, we discuss the local stability and asynchrony respectively for the considered population system under some conditions. We use for our discussion the techniques of operator matrices, Hille-Yosida operators, positivity, spectral analysis as well as Perron-Frobenius theory.

关键词： Population dynamics C0-semigroup stability asynchrony.

Response of successive three generations of cotton,bollworm,Helicoverpa armigera (Hübner),fed on cotton bolls under elevated CO_2

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Journal of Environmental Sciences 2007年第11期19卷 1318-1325页

作者： wu Gang CHEN fa-jun SUN Yu-cheng GE Feng National Key Laboratory of lntegrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing 100101 China Department of Biology Wuhan University of Technology Wuhan 430070 China

The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera （Htibner）, fed on cotton bolls grown under elevated CO2 （double-ambient vs. ambient） in open-top chambers were examined. Significant decreases in protein, total amino acid, water and nitrogen content and increases in free fatty acid were observed in cotton bolls. Changes in quality of cotton bolls affected the growth, development and food utilization of H. armigera. Significantly longer larval development duration in three successive generations and lower pupal weight of the second and third generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower fecundity was also found in successive three generations of H. armigera fed on cotton bolls grown under elevated CO2. The consumption per larva occurred significant increase in successive three generations and frass per larva were also significantly increased during the second and third generations under elevated CO2. Significantly lower relative growth rate, efficiency of conversion of ingested food and significant higher relative consumption rate in successive three generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower potential female fecundity, larval numbers and population consumption were found in the second and third generations of cotton bollworm fed on cotton bolls grown under elevated CO2. The integrative effect of higher larval mortality rate and lower adult fecundity resulted in significant decreases in potential population consumption in the latter two generations. The results show that elevated CO2 adversely affects cotton bolls quality, which indicates the potential population dynamics and potential population consumption of cotton bollworm will alleviate the harm to the plants in the future rising CO2 atmosphere.

关键词： elevated CO2 Helicoverpa armigera growth development fecundity cotton bolls population consumption successive generation

Technical Improvement of Governmental Accounting in the Context of Public Crisis:Based on Event Accounting

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当代财经 2013年第S1期 136-146页

作者： LIU fu-dong LI Jian-fa China University of Petroleum Xiamen University

The occurrence of public crisis would trigger the explosion of resource scarcity within limited space and time,which can result in chaos of public order and market *** crisis becomes serious,the government may dominate public crisis management,so as to perform its public accountability in the special *** one of the important means of relieving the government’s public accountability,governmental accounting should reflect and supervise the resource flow in the handling of public *** application of traditional accounting of value approach may be faced with some difficulties under the crisis conditions,which can be solved by introducing the event accounting for partial *** to the features of public crisis,governmental accounting should pay attention to changing features of the accounting objects,establish the integration pattern of accounting information based on events,trace and reflect the resource flow process under crisis,coordinatethe methods of handling government financial reports,and comprehensively apply all kinds of techniques to improve decision quality of government under crisis.

关键词： public crisis governmental accounting event accounting

Intelligent casting:Empowering the future foundry industry

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China Foundry 2024年第5期21卷 409-426页

作者： Jin-wu Kang Bao-lin Liu Tao Jing Hou-fa Shen School of Materials Science and Engineering Key Laboratory for Advanced Materials Processing TechnologyTsinghua UniversityBeijing 100084China

Emerging technological advances are reshaping the casting sector in latest *** technology is evolving towards intelligent casting paradigm that involves automation,greenization and intelligentization,which attracts more and more attention from the academic and industry *** this paper,the main features of casting technology were briefly summarized and forecasted,and the recent developments of key technologies and the innovative efforts made in promoting intelligent casting process were ***,the technical visions of intelligent casting process were also put *** key technologies for intelligent casting process comprise 3D printing technologies,intelligent mold technologies and intelligent process control *** future,the intelligent mold that derived from mold with sensors,control devices and actuators will probably incorporate the Internet of Things,online inspection,embedded simulation,decision-making and control system,and other technologies to form intelligent cyber-physical casting system,which may pave the way to realize intelligent *** is promising that the intelligent casting process will eventually achieve the goal of real-time process optimization and full-scale control,with the defects,microstructure,performance,and service life of the fabricated castings can be accurately predicted and tailored.

关键词： intelligent casting 3D printing intelligent mold process control cyber-physical casting system embedded simulation