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Tunable Luminescence Properties and Elucidating the Electronic Structures of Single-Phase Spherical BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)Phosphors for Warm-White-Lighting

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Journal of Renewable Materials 2022年第2期10卷 431-451页

作者： Zun Bi ke jia Yunfei Liu Yinong Lyu State key Laboratory of Materials–Orient Chemical Engineering College of Materials Science and EngineeringNanjing Tech UniversityNanjingChina jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM) NanjingChina jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites NanjingChina

A series of uniform single-phase spherical BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors were prepared via a microwave hydrothermal method by using trisodium citrate dehydrate as *** phase structure,morphology and photoluminescence properties were measured by powder X-ray diffraction,scanning electron microscope and fluorescence spectrometer,*** results show that uniform spherical microcrystals with diameters in the range of 2–4μm are *** the phase and morphology of samples are not significantly changed by doping rare earth(RE^(3+))*** the excitation wavelength of 356 and 365 nm,the samples BaWO 4:0.03Dy^(3+),yTm^(3+)can emit cold white *** order to lower the correlated color temperature(CCT)to get a warm white light,the Eu^(3+)ions were doped into BaWO 4:0.03Dy^(3+),0.01Tm^(3+).Especially,under the excitation of 365 nm,BaWO 4:0.03Dy^(3+),0.01Tm^(3+),0.03Eu^(3+)phosphor shew a bright warm white light with color coordi-nate of(0.4013,0.3629)and CCT of 3288 ***,in the BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors,the energy transfer mechanism among Dy^(3+),Tm^(3+)and Eu^(3+)ions have been discussed and the change of electron structures have been calculated by first-principles *** results shew that the uniform single-phase spherical BaWO 4:Dy^(3+),Tm^(3+),Eu^(3+)phosphors could be favorable candidates in warm white LEDs.

关键词： Barium tungstate microwave hydrothermal method spherical warm white lighting electron structures

Numerical Simulation on Effects of Pressure Distribution of Wind Turbine Blade with a Tip Vane

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Journal of Thermal Science 2007年第3期16卷 203-207页

作者： WANG jian-Wen jia Rui-Bo WU ke-Qi School of Energy ＆ Power Engineering Huazhong University of Science ＆ Technology Wu Han 430074 School of Energy ＆ Power Engineering Inner Mongolia University of Technology Hohhot China 010051 School of Energy ＆ environment Engineering Inner Mongolia University of Science ＆ Technology Baotou 014010

It is important to study the pressure distribution on the blade and in the adjacent area while searching the power augmentation theory with adding a tip vane to the wind turbine. This paper shows the CFD simulation relationship of the pressure distribution on the rotor blade and in the adjacent area, after calculating the pressure of the different chordwise and spanwise point on the blade with the tip vane-V（8.8×8） and without the tip vane under tip speed ratio λ 4.5. Combining the isobaric section figure in certain location, it can be seen that the tip vane improve the pressure difference between pressure and suction surface. The most influenced zone is found and these can further display the power augmentation theory of the wind turbine using the tip vane. The simulation calculation was based on N-S equations. 3-D, steady, implicit solver was chosen. Turbulence model was k-ω SST. Discretization scheme is SECOND ORDER UPWIND. Pressure-velocity coupling was a typical SIMPLE scheme. In the whole grid system, two-divided grid formation was adopted, that is, inner region and outer region. Inner region including rectangular solid blade and neighboring, outer region is semi-cylinder. There were together 720,000 nodes with tetra-prism unstructured mesh.

关键词： Wind turbine tip vane pressure distribution numerical simulation

Effect of sintering temperature on the microstructure and thermal conductivity of Al/diamond composites prepared by spark plasma sintering

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 234-240页

作者： ke Chu Cheng-chang jia Xue-bing Liang Hui Chen School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Spark plasma sintering was used to fabricate Al/diamond *** effect of sintering temperature on the microstructure and thermal conductivity（TC） of the composites was investigated with the combination of experimental results and theoretical *** composite sintered at 550℃shows high relative density and strong interfacial bonding,whereas the composites sintered at lower（520CC） and higher（580-600℃） temperatures indicate no interfacial bonding and poor interfacial bonding,*** relative density and strong interfacial bonding can maximize the thermal conductivity of Al/diamond composites,and taking both effects of particle shape and inhomogeneous interfacial thermal conductance into consideration can give a fairly good prediction of composites＇ thermal conduction properties.

关键词： metal matrix composites thermal properties spark plasma sintering interface

A voltage resonance-based single-ended online fault location algorithm for DC distribution networks

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Science China(Technological Sciences) 2016年第5期59卷 721-729页

作者： jia ke LI Meng BI Tian Shu YANG Qi Xun State key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University

A novel single-ended online fault location algorithm is investigated for DC distribution networks. The proposed algorithm calculates the fault distance based on the characteristics of the voltage resonance. The Prony's method is introduced to extract the characteristics. A novel method is proposed to solve the pseudo dual-root problem in the calculation process. The multiple data windows are adopted to enhance the robustness of the proposed algorithm. An index is proposed to evaluate the accuracy and validity of the results derived from the various data windows. The performances of the proposed algorithm in different fault scenarios were evaluated using the PSCAD/EMTDC simulations. The results show that the algorithm can locate the faults with transient resistance using the 1.6 ms data of the DC-side voltage after a fault inception and offers a good precision.

关键词： protection fault location DC distribution VSC voltage resonance Prony's method

Accelerated initiation of oblique detonation induced by disturbance in detonative zone

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Chinese Journal of Aeronautics 2023年第11期36卷 153-164页

作者： Yichen ZHANG Gaoxiang XIANG jia YU ke JIN kek Boon GOH Institute of Extreme Mechanics Northwestern Polytechnical UniversityXi’an 710129China Research and Development Institute Northwestern Polytechnical University in ShenzhenShenzhen 518057China Innovation Center NPU Chongqing Northwestern Polytechnical UniversityChongqing 401135China School of Aerospace Science and Technology Xidian UniversityXi’an 710126China Department of Mechanical Engineering School of EngineeringMonash University MalaysiaSelangor 47500Malaysia

In the real flow for high altitude,the initiation mechanism of the oblique detonation involves the coupling of complex wave structures and combustion waves,which may result in the phenomenon of *** approach of stable initiation is one of the key factors that restricting the oblique detonation engine from theory to *** wave structure,initiation characteristics and characteristic parameters of the flow field are analyzed,the two-dimensional Euler equation considering the detailed chemical reactions of multi-component are ***,the approaches of blunt bump and transverse jet are combined used to shorten the detonation distance of the oblique *** show that these methods can promote the accelerated initiation of the oblique detonation effectively,and the detonation distance can be shortened more than 90%.There are two wave structures induced by the blunt bump:weak coupled and strong coupled,adding the transverse jet promotes the transition between these two wave ***,the shape of the bump and the characteristic parameters of the transverse jet are *** streamline-shape bump can eliminate the recirculation zone formed after the circle bump and the ellipse *** transverse jet will produce an oblique detonation wave at the front of the jet position,which changes the wave structure and initiation mode of the oblique detonation *** is expected to reveal the accelerated initiation mechanism of oblique detonation under the induction zone disturbance and complex flow environment,deepen the understanding of the detonation law of oblique detonation wave under real flow conditions,and provide a scientific basic for the development of the combustor of the oblique detonation engine.

关键词： Acetylene Oblique detonation Initiation acceleration Blunt bump Transverse jet Numerical simulation

Taxonomic revision of Amolops chunganensis(Pope,1929)(Amphibia: Anura) and description of a new species from southwestern China, with discussion on Amolops monticola group and assignment of species groups of the genus Amolops

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Zoological Research 2021年第5期42卷 574-591页

作者： ke jiang Jin-Long Ren Zhi-Tong Lyu Dan Wang Zeng Wang ke Lv jia-Wei Wu jia-Tang Li CAS key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengduSichuan 610041China University of Chinese Academy of Sciences Beijing 100049China State key Laboratory of Biocontrol/The Museum of Biology School of Life Sciences/School of EcologySun Yat-Sen UniversityGuangzhouGuangdong 510275China Swild Studio ChengduSichuan 610015China Chengdu Expert Advisory Committee for Wildlife Conservation and Epidemic Prevention ChengduSichuan 610000China

Amolops chunganensis is a species complex and reported widely from eastern,southern,and southwestern *** on molecular data of 19 populations of *** sensu lato from China,including the population from ***(type locality),we recognize *** sensu stricto and provide an expanded description based on the topotypic *** morphological and molecular data,we describe a new species,Amolops chaochin ***.,from southwestern China,which was previously identified as *** new species is distinguished from all other species in the *** group by:(1)moderate body size,SVL 35.3-39.2 mm in males(n=7),and 50.5-54.4 mm in females(n=7);(2)distinct tympanum,larger than half of eye diameter;(3)small tooth-like projection on anteromedial edge of mandible;(4)circummarginal groove on all fingers;(5)white tubercles on dorsal side of posterior body in both sexes;(6)distinct tubercles on dorsal thigh and white spinose tubercles on dorsal tibia in both sexes;(7)white tubercles on posterior region of tympanum in males;(8)toe webbing reaching disk by dermal fringe on inner side of toe II;(9)vomerine teeth present;(10)transverse bands on dorsal limbs;(11)external vocal sacs present in *** further reviewed the assignment of Amolops groups,with an overall revision of membership and diagnosis of all species groups.

关键词： Amolops chaochin sp.nov. Complex Distribution Amolops gerbillus Amolops chayuensis group Amolops spinapectoralis group

Uncover the Aesthetic Simplicity Associated with Mass Transfer in Energy Materials

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Journal of Electronic Science and Technology 2016年第1期14卷 21-24页

作者： jiang-Wei Li jia Li ke-Chun Wen the School of Energy Science and Engineering University of Electronic Science and Technology of China the Academy of Intangible Cultural Heritage Sichuan Vocational College of Cultural Industries

Aesthetics,referred frequently to as a philosophical term,has played a starring role in forming and evolving a number of aspects of human society,including arts,politics,economics,ethics,***,exploring and investigating the aesthetic phenomena in the scientific field have aroused insightful research findings,which in turn has stimulated research interests in such a science-aesthetics *** particular,better-evaluated aesthetic aspects of the materials field are expected to be uncovered upon the exceedingly-exposed fundamental breakthroughs in researching the basic structure and functionality of *** this report,we glimpse into the aesthetic simplicity of energy materials and comprehend specifically the mass transfer functionalities of key categories of energy materials through an intuitive and bottom-up *** effort aspires to shed new lights on the functionality understanding and manipulation of functional materials in general.

关键词： Aesthetics applicability electrical conduction energy materials gas diffusion simplicity

A potential application in quantum networks-Deterministic quantum operation sharing schemes with Bell states

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Science China(Physics,Mechanics & Astronomy) 2016年第6期59卷 41-48页

作者： ke jia Zhang Long Zhang Ting Ting Song Ying Hui Yang School of Mathematical Science Hei Long Jiang University State key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Department of Computer Science College of Information Science and Technology Jinan University

In this paper, we propose certain different design ideas on a novel topic in quantum cryptography — quantum operation sharing(QOS). Following these unique ideas, three QOS schemes, the "HIEC"(The scheme whose messages are hidden in the entanglement correlation), "HIAO"(The scheme whose messages are hidden with the assistant operations) and "HIMB"(The scheme whose messages are hidden in the selected measurement basis), have been presented to share the single-qubit operations determinately on target states in a remote node. These schemes only require Bell states as quantum resources. Therefore, they can be directly applied in quantum networks, since Bell states are considered the basic quantum channels in quantum networks. Furthermore, after analyse on the security and resource consumptions, the task of QOS can be achieved securely and effectively in these schemes.

关键词： quantum operation sharing quantum secret sharing quantum secure direct communication quantum networks

NiCo alloy nanoparticles anchored on mesoporous Mo_(2)N nanosheets as efficient catalysts for 5-hydroxymethylfurfural electrooxidation and hydrogen generation

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Chinese Journal of Structural Chemistry 2023年第10期42卷 28-36页

作者： ke Wang jia Wu Shuyi Zheng Shibin Yin Guangxi key Laboratory of Electrochemical Energy Materials School of Chemistry and Chemical EngineeringGuangxi University100 Daxue RoadNanning530004China

Construction of highly active and stable bifunctional catalysts for 5-hydroxymethylfurfural oxidation reaction(HMFOR)and hydrogen evolution reaction(HER)is meaningful but remains a ***,the NiCo–Mo_(2)N heterostructure nanosheets catalyst with excellent HMFOR/HER performance is obtained by a simple hydrothermal and calcination *** heterogeneous interface between NiCo and Mo_(2)N induces electron redistribution,regulating the electronic structure of the catalyst and thus optimizing the adsorption/desorption behavior of HMFOR/HER ***,NiCo–Mo_(2)N/NF exhibits superior catalytic activity with a potential of 1.14 V_(RHE)/−17 mV_(RHE)(HMFOR/HER)at±10 mA cm^(−2),and the HMF conversion rate,FDCA yield,and Faradaic efficiency(FE)are∼100%,99.98%,and 98.65%,***,it only requires a low voltage of 1.36 V to achieve 100 mA cm^(−2)for HMFOR-assisted H2 *** study provides a strategy for the development of efficient bifunctional catalysts for sustainable production of high value-added products and hydrogen.

关键词： 5-Hydroxymethylfurfural electrooxidation Catalyst Transition metal nitride Mesoporous Biomass conversion