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航空学报 1991年第12期12卷 B651-B654页

作者：王珉 w.s.lau 南京航空学院香港理工学院

应用于航空航天技术的碳纤维复合材料具有相当高的比强度、高弹性模量、重量轻、热膨胀小、以及具有导电性、对酸、碱有机溶剂有很大的耐蚀性等诸多的优点。但由于材料本身为纤维织物的层压浸渍结构,使其在切削加工时难于达到较高的光... 详细信息

应用于航空航天技术的碳纤维复合材料具有相当高的比强度、高弹性模量、重量轻、热膨胀小、以及具有导电性、对酸、碱有机溶剂有很大的耐蚀性等诸多的优点。但由于材料本身为纤维织物的层压浸渍结构,使其在切削加工时难于达到较高的光洁度与精度,

关键词：碳纤维复合材料电火花加工

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Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： s.w.wi Y.s.Lee Department of Physics and Integrative Institute of Basic sciences Soongsil University

we investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence sensitizer Rare earths

Material characterization and inter/intra-particle validation for DEM simulation of urea coating process

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Particuology 2024年第5期88卷 32-48页

作者： salma A.Nouh KuZilati Kushaari lau Kok Keong shafirah samsuri Chemical Engineering Department Universiti Teknologi PETRONAS32610 Seri IskandarPerak Darul RidzuanMalaysia

Particle coating is a common operation in the controlled-release fertilizer (CRF) industry,where a coating layer is appliedto the urea cores.A discrete element method (DEM) computer simulation was applied to model the coating process for the urea granules using measured model *** accuracy of DEM input parameters for the coating material properties and the physical and mechanical characterizations of urea granules are crucial to the study of particle coating ***,to enhance the simulation accuracy,information on the material properties (urea granules) is *** this study,the elasticity parameters,shear modulus ,coefficient of restitution (CoR),and coefficient of rolling and static friction (CoRF) and (CosF) of urea granules are estimated experimentally in addition to the physical *** sensitivity of the angle of repose of the urea bed was investigated at different coefficients of *** to the obtained experimental value of the angle of repose,values of 0.2 and 0.3 for CoRF and CosF,respectively,were adjusted to obtain consistent urea granules’ motion for simulation and the ***,the spray droplet sizes and velocity distributions were estimated using the video-imaging process *** on this experimental characterization,elasticity parameters and spray properties were integrated into DEM simulation software as input data to perform numerical analysis of the coating process to compare simulation and experimental results,which show uniformity at three different pan speeds with a maximum deviation of 0.033 at 5 ***,consistency between DEM and experiment results was achieved in terms of average coating thickness (μm) of the selected samples and average intra-particle thickness variation ( CoV intra ).These results revealed that the coating film thickness is proportional to the rotation speed for the experiment and *** enhance the inter-particle coating uniformity,the effects of the

关键词： Contact model Discrete element method Urea fertilizer Coating process

Bile acids,gut microbiota,and therapeutic insights in hepatocellular carcinoma

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Cancer Biology & Medicine 2024年第2期21卷 144-162页

作者： Yang song Harry CH lau Xiang Zhang Jun Yu Institute of Digestive Disease and Department of Medicine and Therapeutics State Key Laboratory of Digestive DiseaseLi Ka Shing Institute of Health SciencesCUHK Shenzhen Research InstituteThe Chinese University of Hong KongHong KongChina Department of Gastroenterology Zhongshan Hospital Xiamen UniversityXiamen 361004China

Hepatocellular carcinoma(HCC)is a prevalent and aggressive liver *** interplay between bile acids(BAs)and the gut microbiota has emerged as a critical factor in HCC development and *** normal conditions,BA metabolism is tightly regulated through a bidirectional interplay between gut microorganisms and *** gut microbiota plays a critical role in BA metabolism,and BAs are endogenous signaling molecules that help maintain liver and intestinal *** note,dysbiotic changes in the gut microbiota during pathogenesis and cancer development can disrupt BA homeostasis,thereby leading to liver inflammation and fibrosis,and ultimately contributing to HCC ***,understanding the intricate interplay between BAs and the gut microbiota is crucial for elucidating the mechanisms underlying *** this review,we comprehensively explore the roles and functions of BA metabolism,with a focus on the interactions between BAs and gut microorganisms in ***,therapeutic strategies targeting BA metabolism and the gut microbiota are discussed,including the use of BA agonists/antagonists,probiotic/prebiotic and dietary interventions,fecal microbiota transplantation,and engineered *** summary,understanding the complex BA-microbiota crosstalk can provide valuable insights into HCC development and facilitate the development of innovative therapeutic approaches for liver malignancy.

关键词： Bile acid gut microbiota hepatocellular carcinoma therapeutics microbiota modulation

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Combined Effect of Outdoor Time and Other Modifiable Factors on Myopia Incidence Among Children and Adolescents—9 PLADs,China,2020

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China CDC weekly 2024年第9期6卷 151-156,I0001,I0002页

作者： Panliang Zhong Yunfei Liu Ning Ma Jiajia Dang Di shi shan Cai Ziyue Chen Yanhui Dong Peijin Hu Jun Ma Patrick w.C lau Randall s.stafford Yi song Institute of Child and Adolescent Health School of Public HealthPeking UniversityNational Health Commission Key Laboratory of Reproductive HealthBeijingChina Department of sport Physical Education&HealthHong Kong Baptist UniversityKowloon TongHong Kong Special Administrative RegionChina Department of Medicine Stanford Prevention Research CenterStanford University School of MedicineStanfordCAUnited States

summary what is already known about this topic?Myopia has been identified as a significant emerging challenge and policy priority among children and adolescents in China by the Ministry of Education and seven other *** research has been conducted to investigate the collective impact of outdoor time and other modifiable factors on the incidence of myopia.

关键词： Incidence collective policy

spreadsheet quality assurance:a literature review

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Frontiers of Computer science 2024年第2期18卷 61-82页

作者： Pak-Lok POON Man Fai lau Yuen Tak YU sau-Fun TANG school of Engineering and Technology Central Queensland UniversityMelbourne 3000Australia Department of Computing Technologies Swinburne University of TechnologyHawthorn 3122Australia Department of Computer science City University of Hong KongHong Kong SAR 999077China The Royal Victorian Eye and Ear Hospital East Melbourne 3002Australia

spreadsheets are very common for information processing to support decision making by both professional developers and non-technical end ***,business intelligence and artificial intelligence are increasingly popular in the industry nowadays,where spreadsheets have been used as,or integrated into,intelligent or expert systems in various application ***,it has been repeatedly reported that faults often exist in operational spreadsheets,which could severely compromise the quality of conclusions and decisions based on the *** a view to systematically examining this problem via survey of existing work,we have conducted a comprehensive literature review on the quality issues and related techniques of spreadsheets over a 35.5-year period(from January 1987 to June 2022)for target journals and a 10.5-year period(from January 2012 to June 2022)for target *** other findings,two major ones are:(a)spreadsheet quality is best addressed throughout the whole spreadsheet life cycle,rather than just focusing on a few specific stages of the life cycle.(b)Relatively more studies focus on spreadsheet testing and debugging(related to fault detection and removal)when compared with spreadsheet specification,modeling,and design(related to development).As prevention is better than cure,more research should be performed on the early stages of the spreadsheet life *** by our comprehensive review,we have identified the major research gaps as well as highlighted key research directions for future work in the area.

关键词： decision support system end-user computing end-user programming Excel spreadsheet

Generation and Applications of a Broad Atomic Oxygen Beam with a High Flux-Density via Collision-lnduced Dissociation of O_(2)

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Chinese Journal of Chemistry 2024年第17期42卷 2010-2016页

作者： Zhiqiang Han Liying song Po-wan shum woon-Ming lau Beijing Advanced Innovation Center for Materials Genome Engineering Center for Green InnovationSchool of Mathematics and PhysicsUniversity of Science and Technology BeijingBeijing100083China shunde Innovation school University of Science and Technology BejingFoshanGuangdong 528399China school of Chemistry and Chemical Engineering Linyi UniversityLinyiShandong 276000China The sun Age(Guangdong)New Energy Ltd ZhuhaiGuangdong 519031China

we detail the generation of a pulsed atomic oxygen(AO)broad beam with a high flux-density via collision-induced dissociation of O_(2) to support practical industrial exploitation of AOs,particularly for facilitating 2-dimenstional oxidation/etching at a fast rate of one-monolayer per second in an area≥1000 cm².This innovation fuses the following interdisciplinary concepts:(a)a high density of O^(*) can be produced in an electron-cyclotron-resonance(ECR)O2 plasma;(b)o^(*) can be extracted and accelerated with an aperture-electrode in the plasma.

关键词： Collision Atomic oxygen Ab initio calculations lon-molecule reactions Gas-phase reactions

superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.T.Jeong s.w.Lee w.J.Kim Department of Materials science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy superplasticity severe plastic deformation Grain size Grain growth

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A novel method for the green utilization of waste fried oil

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Particuology 2024年第1期84卷 1-11页

作者： Gan Cheng Mengni Zhang Yang Lu Yanhui Zhang Bin Lin Ee Von lau College of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo454003China Henan Key Laboratory for Green and Efficient Mining&Comprehensive Utilization of Mineral Resources Henan Polytechnic UniversityJiaozuo454003China Collaborative Innovation Center of Coal work safety and Clean High Efficiency Utilization Henan Polytechnic UniversityJiaozuo454003China school of Engineering Monash University MalaysiaSubang JayaSelangor47500Malaysia

waste fried oil was studied to prepare three different types of detergent such as soap,liquid soap and soap powder via saponification *** preparation conditions of soap base were optimized by orthogonal *** specific preparation processes included waste fried oil treatment,orange peel extract preparation,saponification,demoulding and *** showed that the optimal con-ditions for saponification were as follows:ratio of pure waste fried oil to coconut oil=6∶4,alkali liquor(NaOH)mass fraction 30%,saponification temperature 70℃,orange peel extract concentration 15%.The mature soap was then used to make liquid soap and soap powder by surfactant(sodium dodecylbenzene sulfonate,coconut diethanol amide)addition,followed by *** prepared detergent conforms to the production standard of strong decontamination ability,possesses stable performance,is gentle to skin and non-toxic.

关键词： waste fried oil Detergent saponification Decolorization

Evolution of biomass particles during pelletization process

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Particuology 2024年第3期86卷 182-187页

作者： Hamid Rezaei Maryam Tajilrou Jun sian Lee Kanages singaraveloo Anthony lau shahab sokhansanj Biomass and Bioenergy Research Group Department of Chemical and Biological EngineeringUniversity of British ColumbiaVancouverCanada

Pulverizing is an essential unit operation in co-firing biomass with *** are only compatible with pellet forms of fibrous biomass materials and crush them down to their original forming particle *** is why the data on the size distribution of the particles forming a biomass pellet is crucial to achieving optimum combustion *** current study determines the internal particle size distribution of pellets after wet disintegration,following Iso 17830 standard,and aims to suggest improvements to the mentioned standard based on new measured *** were carried out on white wood pellets(no bark)and brown wood pellets containing bark at four water temperatures:20,40,60,and 95℃,with or without *** particle size distribution of the pre-pelletizer wood particles was also measured and compared with particles in the formed *** water temperature of 20℃ was found to be adequate for the complete disintegration of pellets,and no mechanical stirring was *** 30% of particles in the disintegrated pellets were 0.5-1.0 *** changes the particle size distribution to smaller *** disintegrated bark pellets contained more fines than white pellets.

关键词： wood pellets Particle sizes distribution wet disintegration stirring water temperature