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Cutting Performance and Wear Behavior of AITiN-and TiAlSiN-Coated Carbide Tools During Dry Milling of Ti-6Al-4V

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Acta Metallurgica Sinica(English Letters) 2020年第3期33卷 459-470页

作者： Jie Liu Shui-Sheng Zhu xin deng Jian-Ye Liu Zhong-Ping Wang Zhi Qu School of Electromechanical Engineering University of Technology Guangzhou 510006China School of Electromechanical Engineering Guangzhou Panyu PolytechnicGuangzhou 511483China Guangdong Hanbang 3d Technology Co. Ltd.Zhongshan 528427China Heyuan Fuma Cemented Carbide Co. Ltd.Heyuan 517583China Guangdong Fenghua Zhuoli Technology Co. Ltd.Foshan 528225China

Machining,especially dry machining of titanium alloys,has been one of the most significant challenges for carbide cutting *** this study,aluminum-rich AlTiN coating,as well as TiAlSiN nanocomposite coating,were successfully employed for dry milling of Ti-6 A1-4 V alloy with high efficiency and long tool *** the cutting speeds of 150 m/min and 200 m/min,the tool life of the TiAlSiN-coated tool exceeds that of AlTiN-coated tool by 32 and 66%,*** wear modes for both coated tools include the uniform flank wear,smooth wear,chipping,coating and substrate flaking,crater and notch wear,and the wear mechanisms include adhesion,diffusion,oxidation and *** them,the wear mechanism is dominated by the adhesion and oxidation *** compared with AlTiN coating,TiAlSiN coating exhibits better mechanical properties and oxidation resistance,which contribute to a better cutting performance,fewer thermal cracks and smaller and uniform workpiece chips during the dry milling of Ti-6 A1-4 V alloy.

关键词： Cutting performance Wear behavior Ti-6Al-4V AlTiN coating TiAlSiN coating

Neoarchean granitic rocks from the Jiamiao area of the Dabie orogen:Implications on the formation and early evolution of the Yangtze Craton

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Science China Earth Sciences 2022年第8期65卷 1568-1585页

作者： Yang TIAN Wei WANG Wei JIN Yuanbao WU Jing WANG xin deng Sifang HUANG Wuhan Center of Geological Survey China Geological SurveyWuhan430205China State Key Laboratory of Geological Processes and Mineral Resources School of Earth SciencesChina University of GeosciencesWuhan430074China Research Center for Petrogenesis and Mineralization of Granitoid Rocks China Geological SurveyWuhan430205China Institute of Geology Chinese Academy of Geological SciencesBeijing100037China Department of Surveying and Planning Shangqiu Normal UniversityShangqiu476000China

Archean rock exposures in the Yangtze Craton of South China are scarce and have been only studied in small-scale outcrops for understanding its early crustal *** investigations have been carried out for three Neoarchean gneissic granitic plutons from the Dabie orogen in the northeastern margin of the Yangtze *** U-Pb geochronology constrains the emplacement of high-K monzogranite at 2645±30 Ma,high-K syenogranite at 2630±37 Ma and Na-rich granodiorite at 2497±29 *** findings provide direct evidence for the existence of∼2.7-2.5 Ga rocks in the Dabie orogen,which significantly contribute to the distribution and evolution of Neoarchean basement rocks in the Yangtze *** crystals from the three granite samples giveεHf(t)values of−0.9 to 3.7,−4.2 to−0.4 and−4.7 to 0.1,respectively,corresponding to T_(DM2) ages of 3186-2909,3372-3141 and 3297-3005 *** magmatic zircons have δ^(18)O values of 5.06±0.27‰to 5.79±0.30‰(average 5.59‰),6.14±0.24 to 7.35±0.26‰(average 6.87‰)and 5.95±0.17‰to 7.09±0.17‰(average 6.55‰),*** the possible decrease of δ^(18)O value due to the lead loss during post-crystallization alteration,the primary δ^(18)O values might be substantially higher than those of the normal mantle zircon value(δ^(18)O=5.3±0.6‰).These isotopic data indicate that the Jiamiao Neoarchean granites were largely generated through reworking of Paleo-Mesoarchean basement rocks with a minor contribution of supracrustal *** our findings with previous results,we infer that the Archean-Paleoproterozoic complexes/terranes of the Yangtze Craton have distinct petrogenesis and the timings of the transition from Na-rich to high-K granites,crustal growth,and tectonothermal evolution before∼2.0 ***,all of them underwent metamorphism at about 2.0 *** observations also reveal that the Yangtze Craton might comprise several microcontinents that evolved individually and collided to form a unified craton a

关键词： Zircon U-Pb age Hf-O isotopes Neoarchean Dabie orogen Yangtze Craton

Core-shell CdS@ZIF-8 structures for improved selectivity in photocatalytic H2 generation from formic acid

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Nano Research 2016年第9期9卷 2729-2734页

作者： Min Zeng Zhigang Chai xin deng Qi Li Shiqiang Feng Juan Wang Dongsheng Xu College of Chemistry and Chemical Engineering Hubei UniversityWuhan 430062China College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China Key Laboratory for the Synthesis and Application of Organic Functional Molecules Ministry of Education of ChinaWuhan 430062China

Encapsulating well-defined nanoparticles (NPs) into metal-organic frameworks (MOFs) to form core-shell structures not only combines their properties, but may also provide synergistic functionality. Much research attention has been focused on applying core-shell NP@MOF structures to gas storage and sensing, luminescence, lithium ion batteries, selective catalysis, and cascade reactions; however, their application as photocatalysts has been reported much more rarely. Herein, we report the design of a new core-shell structure composed of semiconductor CdS NPs as the core and ZIF-8 as the shell. Both single-core-shell and multiple-core-shell CdS@ZIF-8 were synthesized by varying the concentrations of the ZIF-8 precursor. Photocatalytic hydrogen generation from formic acid over CdS@ZIF-8 demonstrated that core-shell CdS@ZIF-8 structures exhibit increased photocatalytic selectivity for H2 generation from formic acid compared with pure CdS NPs. Furthermore, the concentration of CO in the products was significantly decreased, which benefits the application of CdS@ZIF-8 to proton-exchange membrane fuel cells. Our results provide guidance for the development of new photocatalysts based on NP@MOF core-shell materials.

关键词： metal-organic frameworks (MOFs) cadmium sulfide core-shell photocatalytic H2 generation formic acid selectivity

Construction and Characterization of a cDNA Library from the Pulp of Cara Cara Navel Orange （Citrus sinensis Osbeck）

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Journal of Integrative Plant Biology 2006年第3期48卷 315-319页

作者： Neng-Guo Tao Juan Xu Yun-Jiang Cheng Xiu-xin deng State Key Laboratory of Crop Genetic Improvement National Center of Citrus Breeding Huazhong Agricultural University Wuhan 430070 China

A cDNA library was constructed end characterized from the pulp of Cera Care navel orange （Citrus sinensis Osbeck） at different stages of ripening. Tittering results revealed that approximately 5.086×10^5 independent clones were included in this library. Electrophoresls gel results of 15 randomly selected clones revealed that the size of the insertion fragments ranged from 400 bp to 2 kb, with an average size of 900 bp. Sequencing results of 150 randomly picked clones showed that the recombination rate was 94%. During subsequent sequence analysis, 41 of 139 clones failed to be identified end the amino sequence of 71 clones shared less than 30% identity with related plants in GenBank. Of 27 clones whose amino sequences shared more than 60% identity with other related plants in GenBenk, 17 clones showed an 80% identity with the corresponding candidate genes of citrus. The clone recognized as the type Ⅲ metallothlonein-llke （MT） gene was observed to occur 13 tlmes, Indlcatlng that the protein may play an important role In frult development and rlpenlng.

关键词： Cara Cara navel orange cDNA library Citrus, pulp.

Direct ink writing of TiC-316L metal matrix composites with an epoxy resin-absolute ethanol system

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Rare Metals 2021年第3期40卷 590-599页

作者： Tao Lin Liu-Ping Jin Jia-Yun Yuan Hui-Ping Shao Fu-Cheng Yu Wen-Yuan Li xin-Bo He xin deng Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China School of Material Science and Engineering Lanzhou University of TechnologyLanzhou 730050China Jihua Laboratory Chengye MansionFoshan 528299China School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China

TiC-316 L metal matrix composites were successfully printed with an epoxy resin-absolute ethanol system by direct ink writing(DIW) process in this *** and fracture morphology of the samples were observed by a scanning electron microscope(SEM).Also,the relative density,hardness and transverse rupture strength(TRS) of the sintered samples were *** results show that the samples prepared with a new epoxy resin-absolute ethanol system by the DIW process have high solid content of printing slurry,good surface roughness,high relative density and high *** solid content of the slurry suitable for DIW was 60 vol%,and the internal diameter of the nozzle was set to 0.4 mm,the printing speed was set to 30 mm·s^(-1),and the layer height was set to 0.36 *** the sample with 35 wt% TiC-316 L,the relative density,hardness and TRS of the sintered sample can reach 99.3%,HRA 79.5 and 1438 MPa,respectively.

关键词： DIW MMCs Epoxy resin TiC 316L

A retrieval and validation method for shelterbelt vegetation fraction

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Journal of Forestry Research 2013年第2期24卷 357-360页

作者： deng Rong-xin WANG Wen-juan LI Ying ZHAO Dong-bao Institute of Resources and Environment North China Institute of Water Resources and Electric Power Department of Resources and Environmental Sciences Henan University of Economics and Law

Shelterbelts are important in defending against natural disaster and maintaining ecological balances in farmland. Understanding of the shelterbelt vegetation fraction is fundamental to regional research of shelterbelts using remote sensing. We used SPOT5 imagery with 10×10m spatial resolution in combination with knowledge of the characteristics of shelterbelts to develop a method for retrieval of the vegetation fraction of shelterbelts by the pixel un-mixing model. We then used the method to retrieve values for shelterbelts in study area. By combining the parameters of photographic images with characteristics of shelterbelts, we developed a method for measuring the vegetation fraction of shelterbelts based on an advanced photographic method. We then measured the actual values to validate the retrieval result. The multiple correlation coefficients between the retrieved and measured values were 0.715. Our retrieval and measuring methods presented in this paper accurately reflect field conditions. We suggest that this method is useful to describe shelterbelt structure using remote sensing.

关键词： shelterbelt vegetation fraction retrieval vegetation fraction measuring remote sensing

Automatic architecture design for distributed quantum computing

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CHINESE PHYSICS B 2024年第12期33卷 120302-120302页

作者： Luo, Ting-Yu Zheng, Yu-Zhen Fu, Xiang deng, Yu-xin East China Normal Univ Shanghai Key Lab Trustworthy Comp Shanghai 200062 Peoples R China Natl Univ Def Technol Inst Quantum Informat Coll Comp Changsha 410073 Peoples R China Natl Univ Def Technol Coll Comp State Key Lab High Performance Comp Changsha 410073 Peoples R China Tianjin Inst Adv Technol Tianjin 300459 Peoples R China

In distributed quantum computing (DQC), quantum hardware design mainly focuses on providing as many as possible high-quality inter-chip connections. Meanwhile, quantum software tries its best to reduce the required number of remote quantum gates between chips. However, this "hardware first, software follows" methodology may not fully exploit the potential of DQC. Inspired by classical software-hardware co-design, this paper explores the design space of application-specific DQC architectures. More specifically, we propose AutoArch, an automated quantum chip network (QCN) structure design tool. With qubits grouping followed by a customized QCN design, AutoArch can generate a near-optimal DQC architecture suitable for target quantum algorithms. Experimental results show that the DQC architecture generated by AutoArch can outperform other general QCN architectures when executing target quantum algorithms.

关键词： distributed quantum computing quantum architecture quantum circuit partitioning 03.67.Lx 85.25.-j

Cutting performance of saw blades with microtextured rougher and finisher sawteeth

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Advances in Manufacturing 2024年第2期12卷 317-334页

作者： Yang Lu Jian-xin deng Zhi-Hui Zhang Jia-xing Wu Ran Wang Yi-Chen Bao Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MOE School of Mechanical EngineeringShandong UniversityJinan250061People’s Republic of China

The problems of severe sawtooth wear,harsh sawing noise,and low surface quality during the processing of circular saw blades need to be *** improve the cutting performance of TiC-based cermet saw blades,microtextures parallel to the cutting edge were fabricated on rough and fine sawteeth by laser *** cutting tests were performed on a sawing platform under lubricated *** of the sawing arc length and working sawtooth cutting force variations were developed for sawing steel pipes,and the accuracy of the sawing force model was verified *** results indicate that the variations in the sawing force are proportional to the sawing arc *** circular saw blades with microtextures that did not penetrate the sawtooth rake face exhibited the lowest cutting force,sawing noise,and highest machined surface ***,the worn-out distance of the rougher and finisher sawteeth was reduced by approximately 7.4%and 44.1%,respectively,compared with conventional circular saw *** main failure modes of sawteeth were tip wear,rake face adhesion,and oxidative *** addition,the mechanism by which the textures improve the cutting and wear properties of TiC-based circular saw blades was *** study provided a significant concept for enhancing the cutting performance of circular saw blades and improving the machined surface quality.

关键词： Circular saw blades Micro textures Cutting performance Wear performance

Use of evergreen and deciduous plants by nocturnal-roosting birds:A case study in Beijing

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Avian Research 2024年第2期15卷 211-218页

作者： Yexi Zhao Jiayu Zhang Zihan Li Qinmijia Xie xin deng Chenxi Zhang Nan Wang School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing 100083China

With continually increasing urbanization,the land cover in urban areas continues to change,resulting in the loss of *** are highly sensitive to changes in *** forest birds perch on plants that provide increased safety to reduce the risk of predation,and small birds may also consider insulation when using roosting plants in winter because of cold *** plants thus shape the nocturnal roosting environment of urban birds,and proper planting is essential for the survival of birds at *** use of roosting plants by urban birds should therefore be studied to provide a reference for *** the current study,we observed 1865 nocturnal roosting birds in Beijing from 2021 to 2022,with 23 species of birds from 12 families and 45 species of plants from 22 families *** chinensis exhibited the highest bird rarity-weighted richness,followed by Fraxinus pennsylvanica,Phyllostachys propinqua,Pinus tabuliformis,and Ulmus *** diameter at breast height,tree height,and crown width of plants used by birds was largest in summer and smallest in winter,and the perch height of birds was the highest in spring and summer and the lowest in *** used the highest proportion of deciduous plants in summer and the highest proportion of evergreen plants in winter.A significant seasonal difference in the use of evergreen and deciduous plants by small birds was noted,with a preference for deciduous plants in summer and evergreen plants in winter,while this preference was not found in large *** findings indicate that evergreen plants provide a vital nocturnal roosting environment for small birds in *** provide a better nocturnal roosting habitat for urban birds,we recommend paying attention to the combination of evergreen and deciduous plants when carrying out landscape construction.

关键词： Nocturnal roosting Roosting plant Seasonal variation Urban bird