检索结果-南通市图书馆

Transactions of Nonferrous Metals Society of China 2024年第9期34卷 3002-3015页

作者： Wei-di ZHANG meng-jie TIAN Wei SUN School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing 102600China Hubei Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources Wuhan 430081China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

A novel hydroxamic acid,N-hydroxy-9,10-epoxy group-octadecanamide(N-OH-9,10-O-ODA),was synthesised by modifying the structure of oleic *** carboxyl group of oleic acid was converted into an N-hydroxy amide group,and an epoxy group was introduced into its structure.N-OH-9,10-O-ODA was used as a novel collector in the flotation separation of spodumene from one of its associated gangue minerals,specifically albite.N-OH-9,10-O-ODA exhibits remarkable selectivity,with a stronger affinity for collecting spodumene particles compared to albite *** potential measurements and X-ray photoelectron spectroscopic analysis reveal that the adsorption quantity of N-OH-9,10-O-ODA on spodumene surface is comparable to that on albite ***-principles calculations demonstrate the diverse adsorption configurations of N-OH-9,10-O-ODA on surfaces of spodumene and albite,leading to its distinct collecting abilities for spodumene and albite particles.

关键词： N-hydroxy-9,10-epoxy group-octadecanamide spodumene albite flotation separation oleic acid

Observation of optical rogue waves in 2D optical lattice

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Optics Letters 2024年第7期22卷 77-80页

作者： meng Li jie Song Fuqiang Li Cibo Lou School of Physical Science and Technology Ningbo UniversityNingbo 315211China

We use a broad Gaussian beam with perturbations to motivate rogue waves(RWs)in a two-dimensional optical-induced *** a linear situation,we fail to observe ***,under a nonlinear condition,the probability of RWs in the lattice is less than that in a homogeneous ***,we obtain a shorter long-tail distribution of probability density function in an optical lattice.

关键词： optical rogue waves spatial rogue waves optical-induced lattice.

The Impact of New Regulations on Prevention and Control of E-Cigarettes on Adolescents in Middle Schools—A City in China,2022–2023

在线全文

学校读者我要写书评

暂无评论

China CDC weekly 2024年第14期6卷 289-293页

作者： meng Lyu Wenlong Lu Lanhua Zou Jingfan Xiong jie Yang Tobacco Control Office Chinese Center for Disease Control and PreventionBeijingChina Shenzhen Center for Chronic Disease Control Shenzhen CityGuangdong ProvinceChina

What is already known about this topic?To protect the health of young people from the harmful impacts of electronic cigarettes(e-cigarettes),China has enacted various policies and regulations since *** of October 1,2022,the Electronic Cigarette Management Measures were put into *** prohibited the sale of flavored e-cigarettes,permitting only those of plain tobacco flavor to be *** is added by this report?The illegal market for flavored e-cigarettes,often disguised as milk tea cups,cola cans,and violent bear images,continues to *** is an increased need to bolster support for the prohibition of flavored e-cigarettes and enhance public awareness of associated *** are the implications for public health practice?To advance the health of China’s youth,it is crucial to improve the implementation and understanding of ecigarette policies and guidelines.

关键词： Middle Impact plain

A new TiO_(2) nanorods/MoTe_(2) quantum dots/Al_(2)O_(3) composite photocatalyst for efficient photoelectrochemical water splitting under simulated sunlight

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 Materials Science 2024年第2期18卷 61-74页

作者： jie meng Hongmei Liu Sainan Zhang Baogui Ye Min Feng Daoai Wang School of Chemistry and Chemical Engineering Lanzhou Jiaotong UniversityLanzhou 730000China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Qingdao Centerof Resource Chemistry and New Materials Qingdao 266100China Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai Yantai 265503China

The solar-to-hydrogen conversion using the photoelectrochemical(PEC)method is a practical approach to producing clean ***,it relies on the availability of photocatalyst *** this work,a novel photocatalyst comprising molybdenum telluride quantum dots(MoTe_(2) QDs)-modified titanium dioxide nanorods(TiO_(2) NRs)was prepared for the enhancement of the PEC water splitting performance after combination with a Al_(2)O_(3) layer using the atomic layer deposition(ALD)***_(2) QDs were initially prepared,and then they were loaded onto TiO_(2) NRs using a warm water bath-based heating *** a layer of Al_(2)O_(3) was deposited onto resulted TiO_(2) NRs/MoTe_(2) QDs,the composite TiO_(2) NRs/MoTe_(2) QDs/Al_(2)O_(3) was finally *** simulated sunlight(100 mW·cm^(-2)),such a composite exhibited a maximum photocurrent density of 2.25 mA·cm^(-2) at 1.23 V(versus RHE)and an incident photon-to-electron conversion efficiency of 69.88%at 380 nm,which are 4.33 and 6.66 times those of pure TiO_(2) NRs,***,the composite photocatalyst fabricated in this work may have promising application in the field of PEC water splitting,solarcells andotherphotocatalyticdevices.

关键词： MoTe_(2)quantum dot TiO_(2)nanorod Al_(2)O_(3) atomic layer deposition photoelectrochemistry

A time-dependent luminescent phosphor of Na_(2)Ba_(2)Si_(2)O_(7):Eu for multi-level encryption and dynamic information display

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Advanced Ceramics 2024年第4期13卷 429-436页

作者： jie Shao Xiyang Li meng Liu Haiqin Sun Qiwei Zhang Dengfeng Peng Fuchi Liu College of Physics and Technology Guangxi Normal UniversityGuilin 541004China Guangxi Key Laboratory of Nuclear Physics and Technology Guangxi Normal UniversityGuilin 541004China Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

Photo-stimuli responsive materials show great potential in the fields of information encryption and storage due to their distinctive spatial or temporal color ***,the conventional single or multi-color static outputs by light stimulus difficulty meet practical requirements for high-security optical storage ***,a novel dynamic irradiation-responsive phosphor of Na_(2)Ba_(2)Si_(2)O_(7):Eu is demonstrated,exhibiting high storage stability and convenient readout *** inherent Eu^(2+)luminescence can be dynamically tuned,instantly read out,and conveniently erased by controlling irradiation duration of a portable diode laser(365 nm).The modulation mechanism is unraveled by optically induced oxidation reactions of Eu^(2+)→Eu^(3+)and defects as killer *** excellent luminescence modulation degree(ΔR_(t)=89.5%)and the accompanying larger color contrast enable the creation of invisible optical codes with multi-level encryption in bright or dark *** results indicate potential applications of Na_(2)Ba_(2)Si_(2)O_(7):-based materials in information encryption and invisible optical storage,and are expected to expand more investigations on optically induced PL modulation behaviors based on mixed valences and defects.

关键词： light irradiation luminescent modulation invisible optical storage

Braille Character Segmentation Algorithm Based on Gaussian Diffusion

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第4期79卷 1481-1496页

作者： Zezheng meng Zefeng Cai jie Feng Hanjie Ma Haixiang Zhang Shaohua Li School of Computer Science and Technology Zhejiang Sci-Tech UniversityHangzhou310018China

Optical braille recognition methods typically employ existing target detection models or segmentation modelsfor the direct detection and recognition of braille characters in original braille images. However, these methodsneed improvement in accuracy and generalizability, especially in densely dotted braille image environments. Thispaper presents a two-stage braille recognition framework. The first stage is a braille dot detection algorithmbased on Gaussian diffusion, targeting Gaussian heatmaps generated by the convex dots in braille images. Thisis applied to the detection of convex dots in double-sided braille, achieving high accuracy in determining thecentral coordinates of the braille convex dots. The second stage involves constructing a braille grid using traditionalpost-processing algorithms to recognize braille character information. Experimental results demonstrate that thisframework exhibits strong robustness and effectiveness in detecting braille dots and recognizing braille charactersin complex double-sided braille image datasets. The framework achieved an F1 score of 99.89% for Braille dotdetection and 99.78% for Braille character recognition. Compared to the highest accuracy in existing methods,these represent improvements of 0.08% and 0.02%, respectively.

关键词： Computer vision image recognition optical braille recognition

On the Surface Helium Abundance of B-type Hot Subdwarf Stars from the WD+MS Channel of Type Ia Supernovae

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第5期24卷 21-27页

作者： Rui-jie Ji Xiang-Cun meng Zheng-Wei Liu Yunnan Observatories Chinese Academy of SciencesKunming 650216Kunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China International Centre of Supernovae(ICESUN) Yunnan Key LaboratoryKunming 650216China

The origin of intermediate helium (He)-rich hot subdwarfs is still *** studies have suggested that some surviving Type Ia supernovae (SNe Ia) companions from the white dwarf+main-sequence (WD+MS)channel may contribute to the intermediate He-rich hot ***,previous studies ignored the impact of atomic diffusion on the post-explosion evolution of surviving companion stars of SNe Ia,leading to the aspect that they could not explain the observed surface He abundance of intermediate He-rich hot *** this work,by taking the atomic diffusion and stellar wind into account,we trace the surviving companions of SNe Ia from the WD+MS channel using the one-dimensional stellar evolution code MESA until they evolve into hot *** find that the surface He-abundances of our surviving companion models during their core He-burning phases are in a range of-1■log(N_(He) N_(H))■0,which are consistent with those observed in intermediate He-rich hot *** seems to further support the notion that it is possible for surviving companions of SNe Ia in the WD+MS channel to form some intermediate He-rich hot subdwarfs.

关键词： (stars:)subdwarfs-atomic processes-diffusion

Risk Assessment of Deep-Water Horizontal X-Tree Installation

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2024年第2期38卷 210-220页

作者： meng Wen-bo FU Guang-ming HUANG Yi LIU Shu-jie HUANG Liang GAOYong-hai CNOOC China Limited Zhanjiang BranchZhanjiang 524057China Key Laboratory of Unconventional Oil and Gas Development Ministry of Education(China University of Petroleum(East China))Qingdao 266580China

Due to the high potential risk and many influencing factors of subsea horizontal X-tree installation,to guarantee the successful completion of sea trials of domestic subsea horizontal X-trees,this paper established a modular risk evaluation model based on a fuzzy fault ***,through the analysis of the main process oftree down and combining the Offshore&Onshore Reliability Data(OREDA)failure statistics and the operation procedure and the data provided by the job,the fault tree model of risk analysis of the tree down installation was ***,by introducing the natural language of expert comprehensive evaluation and combining fuzzy principles,quantitative analysis was carried out,and the fuzzy number was used to calculate the failure probability of a basic event and the occurrence probability of a top ***,through a sensitivity analysis of basic events,the basic events of top events significantly affected were determined,and risk control and prevention measures for the corresponding high-risk factors were proposed for subsea horizontal X-tree down installation.

关键词： subsea horizontal X-tree risk assessment fuzzy fault tree modular risk evaluation model

Effect of electrical parameters and slag system on macrostructure of electroslag ingot

在线全文

学校读者我要写书评

暂无评论

China Foundry 2024年第1期21卷 44-50页

作者： Bing-jie Wang Yu Wang meng-jun Wang Lei Zhao Li-zhong Chang Xiao-fang Shi School of Metallurgy engineering Anhui University of TechnologyMa'anshan 243002AnhuiChina

To investigate the influence of electric parameters and slag system on the solidification quality of electroslag ingot during electroslag remelting,different power supply modes,current strengths and remelting slag systems were used to conduct electroslag remelting experiments on 304L austenitic stainless steel,and the macrostructure of electroslag ingots was *** results indicate that the depth of the metal pool decreases with the reduction of remelting frequency in the low frequency power supply *** effects of different power supply modes,such as low-frequency,direct current straight polarity(DCSP),and direct current reverse polarity(DCRP),on reducing the depth of the metal pool increase in that *** reducing the remelting current strength in the same power supply mode,the depth of metal pool is *** compared to the binary slag system of 70%CaF2+30%Al2O3,the ternary slag system of 60%CaF2+20%Al2O3+20%CaO is more effective in reducing the depth of the metal pool during *** the 60%CaF2+20%Al2O3+20%CaO ternary slag system results in a shallower and flatter metal pool,with columnar crystal growth occurring closer to the axial *** effect is observed for both low frequency and direct current(DC)power supply modes.

关键词： electroslag remelting frequency slag system solidification quality

New indices to balanceα-diversity against tree size inequality

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2024年第1期35卷 229-237页

作者： Li Zhang Brady K.Quinn Cang Hui meng Lian Johan Gielis jie Gao Peijian Shi College of Ecology and Environment Bamboo Research InstituteNanjing Forestry University159 Longpan RoadNanjing 210037People’s Republic of China Fisheries and Oceans Canada Andrews Biological Station125 Marine Science DriveSt.AndrewsNB E5B 0E4Canada Department of Mathematical Sciences Centre for Invasion BiologyStellenbosch UniversityMatieland 7602South Africa Mathematical and Physical Biosciences African Institute for Mathematical SciencesCape Town 7945South Africa Department of Biosciences Engineering University of AntwerpB-2020 AntwerpBelgium College of Life Science Xinjiang Normal University102 Xinyi RoadUrumqi 830054People’s Republic of China

The number and composition of species in a community can be quantified withα-diversity indices,including species richness(R),Simpson’s index(D),and the Shannon-Wiener index(H΄).In forest communities,there are large variations in tree size among species and individu-als of the same species,which result in differences in eco-logical processes and ecosystem ***,tree size inequality(TSI)has been largely neglected in studies using the available diversity *** TSI in the diameter at breast height(DBH)data for each of 99920 m×20 m forest census quadrats was quantified using the Gini index(GI),a measure of the inequality of size *** generalized performance equation was used to describe the rotated and right-shifted Lorenz curve of the cumulative proportion of DBH and the cumulative proportion of number of trees per *** also examined the relationships ofα-diversity indices with the GI using correlation *** generalized performance equation effectively described the rotated and right-shifted Lorenz curve of DBH distributions,with most root-mean-square errors(990 out of 999 quadrats)being1−GI)×D,and(1−GI)×H’.These new indices were significantly correlated with the original D and H΄,and did not increase the extent of variation within each group of *** study presents a useful tool for quantifying both species diversity and the variation in tree sizes in forest communities,especially in the face of cumulative species loss under global climate change.

关键词： Diameter at breast height(DBH) Gini index Shannon-Wiener index Simpson’s index Quadrat Tree size