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Diversified Polyketides and Nitrogenous Compounds from the Mangrove Endophytic Fungus Penicillium steckii SCSIO 41025

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Chinese Journal of Chemistry 2021年第8期39卷 2132-2140页

作者： chun-Mei Chen Wei-Hao Chen Hua-Ming tao Bin Yang Xue-Feng Zhou Xiao-Wei luo Yong-Hong Liu CAS Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Key Laboratory of Marine Materia Medica South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhouGuangdong 510301China Institute of Marine Drugs Guangxi University of Chinese MedicineNanningGuangxi 530200China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) GuangzhouGuangdong 511458China University of Chinese Academy of Sciences Beijing 100049China School of Traditional Chinese Medicine Southern Medical UniversityGuangzhouGuangdong 510515China

Four new polyketide decalin derivatives,penicisteck acids A-D(1-4),and three new nitrogenous compounds(7-9)z together with eight previously reported compounds,were isolated from the mangrove endophytic fungus Penicill... 详细信息

关键词： Mangrovee ndophytic fungus Penicillium steckii Polyketides Alkaloids Biological activity

Toolpath Interpolation and Smoothing for Computer Numerical Control Machining of Freeform Surfaces: A Review

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International Journal of Automation and computing 2020年第1期17卷 1-16页

作者： Wen-Bin Zhong Xi-chun luo Wen-Long Chang Yu-Kui Cai Fei Ding Hai-tao Liu Ya-Zhou Sun Centre for Precision Manufacturing Department of DesignManufacture&Engineering Management(DMEM)University of StrathclydeGlasgow G11XJUK Engineering and Physical Sciences Research Council(EPSRC)Future Metrology Hub Centre for Precision TechnologiesUniversity of HuddersfieldHuddersfield HD13DHUK School of Mechatronic Engineering Harbin Institute of TechnologyHarbin 150001China

Driven by the ever increasing demand in function integration,more and more next generation high value-added products,such as head-up displays,solar concentrators and intra-ocular-lens,etc.,are designed to possess freeform(i.e.,non-rotational symmetric)*** toolpath,composed of high density of short linear and circular segments,is generally used in computer numerical control(CNC)systems to machine those ***,the discontinuity between toolpath segments leads to high-frequency fluctuation of feedrate and acceleration,which will decrease the machining efficiency and product surface *** by the ever-increasing need for high-speed high-precision machining of those products,many novel toolpath interpolation and smoothing approaches have been proposed in both academia and industry,aiming to alleviate the issues caused by the conventional toolpath representation and interpolation *** paper provides a comprehensive review of the state-of-the-art toolpath interpolation and smoothing approaches with systematic *** advantages and disadvantages of these approaches are *** future research directions are also offered.

关键词： Computer numerical control(CNC) toolpath interpolation smoothing freeform surface

Evaluation of vibration stress of TA11 titanium alloy blade by quantitative fractography

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Rare Metals 2014年第3期33卷 263-269页

作者： Xin-Ling Liu Yuan-Ming Xu chun-Hu tao Beijing Institute of Aeronautical Materials Aviation Industries of China Key Laboratory of Aeronautical Materials Testing and Evaluation Chinatao Failure Analysis Center of Aviation Industries of China School of Aeronautical Science and Engineering Beijing University of Aeronautics and Astronautics Beijing Key Laboratory of Aeronautical Materials Testing and Evaluation

Vibration fatigue is the main failure mode of compressor blade. Evaluating the vibration stress of blade that leads to cracking is very useful for analysis of vibration fatigue. In this paper, fatigue stress estimation methods by quantitative fractography were studied through experimental blade and in-service first-stage compressor blade in order to evaluate the initiation vibration stress of in-service blade. The analysis process of initiation vibration stress was established. The evaluating result of vibration stress of in-service blade subjected to centrifugal force and bending vibration stress agrees with aero engine test result. It is shown that the evaluation method can not only evaluate the equivalent fatigue stresses of different crack depths but also yield the initiation equivalent fatigue stress.

关键词： Compressor blade Bending vibration Stress evaluate Quantitative fractography

Petrogenesis of the Granites in the Yandangshan Area, Southeastern China: Constraints from SHRIMP U-Pb Zircon Age and Trace Elements, and Sr-Nd-Hf Isotopic Data

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Journal of Earth Science 2020年第4期31卷 693-708页

作者： Yaqin luo Haiyan Qin tao Wu Zilong Li School of Earth Sciences Zhejiang UniversityHangzhou 310027China The 11th Geological Section of Zhejiang Province Wenzhou 325006China Ocean College Zhejiang UniversityZhoushan 316021China

New geochemical and geochronological data of two types of granites,which are located in Yandangshan area,southeastern Zhejiang Province,were presented to constrain their magma condition,origin and the genetic relationship between *** SHRIMP zircon U-Pb dating of Dongshan and Hesheng granite in Yandangshan area shows that they were formed at 114±1 and 103±2 Ma,*** from the Dongshan granite have high Si O2(76.4 wt.%–76.9 wt.%)and total alkaline(K2O+Na2O=8.35 wt.%–8.47 wt.%)contents,but low Fe OT(0.89 wt.%–1.15 wt.%),Mg O(0.21 wt.%–0.22wt.%),and Ca O(0.24 wt.%–0.34 wt.%)contents and high A/CNK(~1.1)values,belonging to the peraluminous and magnesian *** Hesheng granite has high Si O2(72.2 wt.%–77.5 wt.%),total alkaline(K2O+Na2O=8.05 wt.%–9.41 wt.%)and Fe OT contents(1.20–2.06),and high A/CNK values(1.0–1.1),but low in Mg O(0.12 wt.%–0.29 wt.%)and Ca O(0.24 wt.%–0.34 wt.%)*** from the Hesheng granite also have high Fe OT/Mg O(6.9–10.0)and 10 000×Ga/Al(2.6–3.4)ratios similar to the ferroan/A-type *** the samples are enriched in LREE but have produced negative Eu anomalies(Eu/Eu*Dongshan=0.45–0.47;Eu/Eu*Hesheng=0.17–0.55),Ba,Nb,and Ta,while the REE contents of the ferroan/A-type granite(Hesheng)are higher than that of the magnesian granite(Dongshan).The(87Sr/86Sr)i value of the magnesian granite is slightly higher than that of the ferroan/A-type granite and itsεNd(t)value(-6.8)is lower than the latter(-6.0–-5.9).In addition,theεHf(t)value(-11.8–-4.2)of magnesian granite is also lower than that of the ferroan/A-type granite(-8.3–-2.0),indicating that there may be more mantle-derived components in the source area of the ferroan/A-type *** saturation thermometer(TZr)and Ti-in-zircon thermometer(TZircon)are used to estimate the temperature of the magma source,and the results show that the magma temperature of the magnesian granite(average TZr=798oC;average TZircon=792oC)is lower than that of the ferroan/A-type grani

关键词： magnesian and ferroan/A-type granite petrogenesis Yandangshan South China

A review of the resistome within the digestive tract of livestock

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Journal of Animal Science and Biotechnology 2022年第3期13卷 642-661页

作者： tao Ma Tim A.McAllister Le luo Guan Key laboratory of Feed Biotechnology of the Ministry of Agriculture Institute of Feed ResearchChinese Academy of Agricultural SciencesBeijing 100081China Department of Agricultural Food and Nutritional ScienceUniversity of AlbertaT6G2P5EdmontonABCanada Lethbridge Research and Development Centre LethbridgeAB T1J 4P4Canada

Antimicrobials have been widely used to prevent and treat infectious diseases and promote growth in food-production ***,the occurrence of antimicrobial resistance poses a huge threat to public and animal health,especial y in less developed countries where food-producing animals often intermingle with *** limit the spread of antimicrobial resistance from food-production animals to humans and the environment,it is essential to have a comprehensive knowledge of the role of the resistome in antimicrobial resistance(AMR),The resistome refers to the col ection of al antimicrobial resistance genes associated with microbiota in a given *** dense microbiota in the digestive tract is known to harbour one of the most diverse resistomes in *** of the resistome in the digestive tract of humans and animals are increasing exponential y as a result of advancements in next-generation sequencing and the expansion of bioinformatic resources/tools to identify and describe the *** this review,we outline the various tools/bioinformatic pipelines currently available to characterize and understand the nature of the intestinal resistome of swine,poultry,and *** then propose future research directions including analysis of resistome using long-read sequencing,investigation in the role of mobile genetic elements in the expression,function and transmission of *** review outlines the current knowledge and approaches to studying the resistome in food-producing animals and sheds light on future strategies to reduce antimicrobial usage and control the spread of AMR both within and from livestock production systems.

关键词： Antimicrobial resistance Antimicrobial resistance gene Digestive tract Food-producing animal Metagenomic sequencing Resistome

Cluster-Based Interference-Free MAC Protocol with Load Aware in Software Defined VANET

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China Communications 2020年第12期17卷 217-234页

作者： Yangshui Gao tao luo Xinxin He Zhilong Zhang Beijing Laboratory of Advanced Information Networks Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and TelecommunicationsBeijing 100876China School of Mathematics and Computer Dali UniversityDali 671003China

In order to reduce the interference,a novel,cluster-based medium access control(MAC)protocol with load aware for VANETs is proposed in this ***,all vehicles on roads are grouped into stable clusters in the light of their direction,number of neighbors,link reliability,and traffic *** utilizing the advantages of centralized control in software defined VANETs(SDVN),cluster stability can be maintained in ***,a contention-free MAC mechanism composed of inter-cluster multi-channel allocation and intra-cluster dynamic TDMA frame allocation is proposed to prevent co-channel interference and hidden terminal *** results show that the proposed protocol outperforms some existing protocols in cluster stability,delivery ratio,throughput and delay performance.

关键词： SDVN MAC co-channel interference non-safety services cluster

An image mosaic technique with non-overlapping regions based on microscopic vision in precision assembly

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Nanotechnology and Precision Engineering 2023年第4期6卷 66-74页

作者： Yawei Li Xiaodong Wang tao Wang Yi luo Key Laboratory for Micro/Nano Technology and System of Liaoning Province Dalian University of TechnologyDalian 116024China Key Laboratory for Precision and Non-Traditional Machining of Ministry of Education Dalian University of TechnologyDalian 116024China

Microscopic vision has been widely applied in precision *** achieve sufficiently high resolution in measurements for precision assembly when the sizes of the parts involved exceed the field of view of the vision system,an image mosaic technique must be *** this paper,a method for constructing an image mosaic with non-overlapping areas with enhanced efficiency is ***,an image mosaic model for the part is created using a geometric model of the measurement system installed on a X-Y-Z precision stages with high repeatability,and a path for image acquisition is ***,images are captured along the same path for a specified calibration plate,and an entire image is formed based on the given *** measurement results obtained from the specified calibration plate are utilized to identify mosaic errors and apply compensation for the part requiring *** results show that the maximum error is less than 4μm for a camera with pixel equivalent 2.46μm,thereby demonstrating the accuracy of the proposed *** image mosaic technique with non-overlapping regions can simplify image acquisition and reduce the workload involved in constructing an image mosaic.

关键词： Image mosaic Microscopic vision Visual measurement Precision assembly

Minimizing Outage Probability Driven Wireless Backhaul Scheme in Heterogeneous Networks

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China Communications 2022年第6期19卷 248-262页

作者： Zhenxing Li Rui Xie Kai luo tao Jiang Research Center of 6G Mobile Communications School of Cyber Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Shanghai Electric Control Research Institute Shanghai 200092China

Heterogeneous networks(Het Nets)attracts a lot of attention due to its high capacity and large coverage for future communication ***,with the large-scale deployment of small cells,HetNets bears dramatically increasing backhaul,which leads to a decrease of the outage *** improve the outage performance of Het Nets,we propose a wireless backhaul scheme for a two-layer HetNets,which automatically switches the three basic modes of orthogonal multiple access(OMA),nonorthogonal multiple access(NOMA)and cooperative non-orthogonal multiple access(CNOMA).First,we analyze the backhaul capacity and outage performance of these three basic ***,we design the power allocation schemes based on minimizing outage probability for NOMA and *** the designed power allocation schemes,we propose a wireless backhaul scheme that switches the three modes according to the channel quality among different base stations(BSs).Moreover,the closed-form of the corresponding outage probability is *** with the three basic modes,the proposed wireless backhaul scheme can achieve the best outage performance and a higher backhaul ***,all the analytical results are validated by simulations.

关键词： Het Nets wireless backhaul NOMA outage probability backhaul capacity

An Overview of Privacy Preserving Schemes for Industrial Internet of Things

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China Communications 2020年第10期17卷 1-18页

作者： Yan Huo chun Meng Ruinian Li tao Jing School of Electronics and Information Engineering Beijing Jiaotong UniversityBeijing 100044China The Department of Computer Science Bowling Green State UniversityBowling GreenOhio43403USA

The concept of Internet of Everything is like a revolutionary storm,bringing the whole society closer *** of Things(IoT)has played a vital role in the *** the rise of the concept of Industry 4.0,intelligent transformation is taking place in the industrial *** a new concept,an industrial IoT system has also attracted the attention of industry and *** an actual industrial scenario,a large number of devices will generate numerous industrial *** computing efficiency of an industrial IoT system is greatly improved with the help of using either cloud computing or edge ***,privacy issues may seriously harmed interests of *** this article,we summarize privacy issues in a cloud-or an edge-based industrial IoT *** privacy analysis includes data privacy,location privacy,query and identity *** addition,we also review privacy solutions when applying software defined network and blockchain under the above two ***,we analyze the computational complexity and privacy protection performance of these ***,we discuss open issues to facilitate further studies.

关键词： privacy preserving cloud computing edge computing industrial Internet of Things