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Fabrication and application of nano/microcrystalline composite diamond coated drawing dies using alternative carbon sources

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Transactions of Nonferrous Metals Society of China 2018年第8期28卷 1602-1610页

作者： cheng-chuan wang Xin-chang wang Fang-hong SUN School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Nano/microcrystalline composite diamond films were deposited on the holes of WC-6%Co drawing dies by a two-step procedure using alternative carbon sources, i.e., methane for the microcrystalline diamond（MCD） layer and acetone for the nanocrystalline diamond（NCD） layer. Moreover, the monolayer methane-MCD and acetone-NCD coated drawing dies were fabricated as comparisons. The adhesion and wear rates of the diamond coated drawing dies were also tested by an inner hole polishing apparatus. Compared with mono-layer diamond coated drawing die, the composite diamond coated one exhibits better comprehensive performance, including higher adhesive strength and better wear resistance than the NCD one, and smoother surface（Ra=65.3 nm） than the MCD one（Ra=95.6 nm） after polishing at the same time. Compared with the NCD coated drawing die, the working lifetime of the composite diamond coated one is increased by nearly 20 times.

关键词： microcrystalline nanocrystalline composite diamond film WC Co drawing die alternative carbon source

Co evolutions for WC-Co with different Co contents during pretreatment and HFCVD diamond film growth processes

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Transactions of Nonferrous Metals Society of China 2018年第3期28卷 469-486页

作者： Xin-chang wang cheng-chuan wang Wei-kai HE Fang-hong SUN State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Physics and Technology University of Ji’nanJi’nan 250022China

Systematical researches were accomplished on WC-Co with different Co contents(6%,10%and 12%,mass fraction).Based on the XPS and EDX,from orthogonal pretreatment experiments,it is indicated that the acid concentration,the time of the acid pretreatment and the original Co content have significant influences on the Co-removal depth(D).Moreover,the specimen temperature,original Co content and Co-removal depth dependences of the Co evolution in nucleation,heating(in pure H2 atmosphere)and growth experiments were discussed,and mechanisms of Co evolutions were summarized,providing sufficient theoretical bases for the deposition of high-quality diamond films on WC-Co substrates,especially Co-rich WC-Co *** is proven that the Co-rich substrate often presents rapid Co *** high substrate temperature can promote the Co diffusion in the pretreated substrate,while acts as a Co-etching process for the untreated *** is finally found that the appropriate Co-removal depth for the WC-12%Co substrate is 8-9μm.

关键词： HFCVD diamond film WC-Co Murakami-acid pretreatment Co content Co evolution

Confinement of Fe atoms between MoS_(2) interlayers drives phase transition for improved reactivity in Fenton-like reactions

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Nano Research 2024年第3期17卷 1132-1139页

作者： Yibing Sun Yu Zhou Hongchao Li chuan wang Xuan Zhang Qian Ma Yingchun cheng Jieshu Qian Bingcai Pan Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse School of Environmental and Biological EngineeringNanjing University of Science and TechnologyNanjing 210094China Key Laboratory of Flexible Electronics and Institute of Advanced Materials Jiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing Tech UniversityNanjing 211816China Department of General Dentistry Affiliated Stomatological Hospital of Nanjing Medical UniversityJiangsu Province Key Laboratory of Oral DiseasesNanjing 210029China Research Center for Environmental Nanotechnology(ReCENT) State Key Laboratory of Pollution Control and Resources ReuseSchool of EnvironmentNanjing UniversityNanjing 210023China

Phase manipulation of MoS_(2) from thermodynamically stable 2H phase to the unstable but more reactive 1T phase represents a crucial strategy for improving the reactivity in many *** widely adopted wet chemistry approach uses intercalating entities especially alkali metal ions to achieve the phase transition;however,these entities are normally inert for the target ***,we describe the first use of iron atoms for the intercalation of 2H-MoS_(2) layers,driving the partial transition from 2H to 1T ***,in the peroxymonosulfate(PMS)-based Fenton-like reactions,the interlayered confinement of Fe atoms not only activates the inert basal plane,but also adds more reactive Fe sites for the formation of metal-PMS complex as primary reactive species for pollutant *** the degradation of a model pollutant carbamazepine(CBZ),the Fe-intercalated MoS_(2) exhibits a first order rate constant 13.3 times higher than 2H-MoS_(2).This strategy is a new direction for manipulating the phase composition and boosting the catalytic reactivity of MoS_(2)-based catalysts in various scenarios,including environmental remediation and energy applications.

关键词： confinement MoS_(2) Fe atoms Fenton-like reactions hydrogen evolution reaction

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斜激波串与上游激波干扰特性试验研究

宇航学报 2018年第3期29卷 300-307页

作者：程川王成鹏程克明南京航空航天大学宇航学院南京210016

为研究斜激波串在背压条件下前移与上游激波相互干扰的流场结构和运动规律,在来流为马赫数2.7的直管道内设计一种等宽度斜楔,采用动态压力测量、高速纹影和粒子图像测速(PIV)技术等手段进行了试验。研究结果表明:内置斜楔在管道内产生... 详细信息

为研究斜激波串在背压条件下前移与上游激波相互干扰的流场结构和运动规律,在来流为马赫数2.7的直管道内设计一种等宽度斜楔,采用动态压力测量、高速纹影和粒子图像测速(PIV)技术等手段进行了试验。研究结果表明:内置斜楔在管道内产生入射激波、分离激波、膨胀波、再附激波和激波诱导分离等复杂上游激波流场,在分离区附近形成有顺压梯度和逆压梯度的区域。当增大下游压比时,斜激波串逐渐向上游激波流场移动;经过斜楔产生的分离区时,斜激波串的移动速度急剧提升,同时出现非对称分离偏转方向的切换。对比了三种长度尺寸的等楔角斜楔所产生的上游激波流场的差异性,发现在相同的斜楔前缘起始点和楔角时,随着斜楔长度的增加,上游激波流场中激波诱导的分离尺度逐渐变大。

关键词：斜激波串斜楔运动特性边界层分离偏转切换

Carbon-coated hybrid crystals with fast electrochemical reaction kinetics for ultra-stable and high-load sodium-ion batteries

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Rare Metals 2024年第2期43卷 647-657页

作者： chuan Ou Ming-Dong Tan Zhen-Bang Li Zhao-Jie Li Fei Tian Zheng-Ping Qiao Dan-Ni Lei cheng-Xin wang State Key Laboratory of Optoelectronic Materials and Technologies School of Materials Science and EngineeringSun Yat-Sen UniversityGuangzhou510275China

Owing to its high theoretical capacity and low cost,Sn has attracted significant attention in sodium-ion ***,the slow kinetics of electrochemical reactions and the rapid decay of capacity resulting from drastic changes in the volume of Sn,as well as persistent side reactions between Sn and the organic electrolyte during the(de)sodium process,have limited its *** improve the electrochemical performance of Sn-based materials,the bottom-up method is normally used to prepare carbon-coated ***,its complex preparation processes and harsh conditions make it unsuitable for practical ***,a carbon-coated hybrid crystal composite(Sn/SnO_(x)@C)was prepared using an up-bottom method with commercial Sn/SnO *** effects accelerate the electrochemical kinetics and inhibit the coarsening of Sn *** Sn/SnO_(x)@C composite electrode exhibited capacity retention of 80.7%even after approximately 1000 cycles(360.4 mAh·g^(−1)) at a current density of 1 A·g^(−1).The high-load Na_(3)V_(2)(PO4)3||Sn/SnO_(x)@C full cell presents a capacity retention rate of 91.7%after 150 cycles at the current density of 0.5 A·g^(−1).This work may significantly accelerate the commercialization of the Sn/SnO_(x)@C composite in sodium-ion batteries with high energy density.

关键词： Sodium-ion batteries(SIBs) Sn-based anode Ultraviolet curing Up-bottom method

Triple reverse order law for the Drazin inverse

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 55-68页

作者： wang Hua ZHONG cheng-cheng College of Sciences Inner Mongolia University of TechnologyHohhot 010051China College of Engineering University of Jinan Quancheng CollegeYantai 265600China

In this paper,we investigate the reverse order law for Drazin inverse of three bound-ed linear operators under some commutation ***,the Drazin invertibility of sum is also obtained for two bounded linear operators and... 详细信息

关键词： Drazin inverse reverse order law space decomposition

Determining an optimal control strategy for anthropogenic VOC emissions in China based on source emissions and reactivity

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Journal of Environmental Sciences 2024年第2期136卷 248-260页

作者： Ruipeng wang Xiaoqi wang Shuiyuan cheng Jiaxian Zhu Xinyu Zhang Long cheng Kai wang Key Laboratory of Beijing on Regional Air Pollution Control Faculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

An evidence-based control strategy for emission reduction of VOC sources can effectively solve the regional PM2.5and O3compound pollution in *** estimated the anthropogenic VOC emission inventory in China in 2018 and established a source profile database containing 129 sources based on localized detection and the latest research ***,the distribution of the ozone formation potential(OFP)and secondary organic aerosol formation potential(SOAFP)for emission sources was ***,priority control routes for VOC emission sources were proposed for different *** VOC emissions in China reached 27,211.8 Gg in 2018,and small passenger cars,industrial protective coatings,biomass burning,heavy trucks,printing,asphalt paving,oil storage and transportation,coking,and oil refining were the main *** protective coatings,small passenger cars,and biomass burning all contributed significantly to OFP and *** in emission reduction control should be given to industrial protective coatings,small passenger cars,heavy trucks,coking,printing,asphalt paving,chemical fibers,and basic organic chemical sources over the medium and long term in *** addition,the priority control route for VOC emission sources should be adjusted according to the variations in VOC emission characteristics and regional differences,so as to obtain the maximum environmental benefits.

关键词： Volatile organic compounds Anthropogenic emission inventory Reactivity Emission projection Priority control route

A new scheme of PM_(2.5)and O_(3) control strategies with the integration of SOM,GA and WRF-CAMx

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Journal of Environmental Sciences 2024年第4期138卷 249-265页

作者： Wenjiao Duan Xiaoqi wang Shuiyuan cheng Ruipeng wang Key Laboratory of Beijing on Regional Air Pollution Control Faculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

Previous air pollution control strategies didn’t pay enough attention to regional collaboration and the spatial response sensitivities,resulting in limited control effects in *** study proposed an effective PM_(2.5)and O_(3) control strategy scheme with the integration of Self-Organizing Map(SOM),Genetic Algorithm(GA)and WRF-CAMx,emphasizing regional collaborative control and the strengthening of control in sensitive *** scheme embodies the idea of hierarchical management and spatial-temporally differentiated management,with SOM identifying the collaborative subregions,GA providing the optimized subregion-level priority of precursor emission reductions,and WRF-CAMx providing response sensitivities for grid-level priority of precursor emission *** Beijing-Tianjin-Hebei and the surrounding area(BTHSA,“2+26”cities)as the case study area,the optimized strategy required that regions along Taihang Mountains strengthen the emission reductions of all precursors in PM_(2.5)-dominant seasons,and strengthen VOCs reductions but moderate NOx reductions in O_(3)-dominant *** spatiotemporally differentiated control strategy,without additional emission reduction burdens than the 14th Five-Year Plan proposed,reduced the average annual PM_(2.5)and MDA8 O_(3) concentrations in 28 cities by 3.2%-8.2% and 3.9%-9.7% respectively in comparison with non-differential control strategies,with the most prominent optimization effects occurring in the heavily polluted seasons(6.9%-18.0%for PM_(2.5)and 3.3%-14.2% for MDA8 O_(3),respectively).This study proposed an effective scheme for the collaborative control of PM_(2.5)and O_(3) in BTHSA,and shows important methodological implications for other regions suffering from similar air quality problems.

关键词： PM_(2.5)and O_(3)control SOM GA WRF-CAMx Bionic algorithm Machine learning

Multiwavelength Observations of the Infrared Dust Bubble N75 and its Surroundings

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Research in Astronomy and Astrophysics 2024年第4期24卷 262-270页

作者： Quan-Ling Cui chuan-Peng Zhang Jun-Jie wang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Science Qiqihar UniversityQiqihar 161006China Guizhou Radio Astronomical Observatory Guizhou UniversityGuiyang 550000China

Infrared dust bubbles play an important role in the study of star formation and the evolution of the interstellar *** this work,we study the infrared dust bubble N75 and the infrared dark cloud G38.93 mainly using the tracers C^(18)O,HCO^(+),HNC and N_(2)H^(+)observed by the 30 m IRAM *** also study the targets using data from large-scale surveys:GLIMPSE,MIPSGAL,GRS,NRAO VLA Sky Survey and Bolocam Galactic Plane *** found that the C^(18)O emission is morphologically similar to the Spitzer IRAC 8.0μm ***1.1 mm cold dust emission of G38.93 shows an elongated structure from southwest to *** ionized gas from G38.93 is surrounded by polycyclic aromatic hydrocarbon emission,which may be excited by radiation from *** found that the identified young stellar objects tend to cluster around G38.93 and are mostly in class II with several class I cases distributed around N75,but no class II *** also found evidence of expanding feedback,which could have triggered star formation.

关键词： ISM:bubbles infrared:ISM galaxies:star formation