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Enhanced red luminescence of Ca_(3)Si_(2−x)M_(x)O_(7):Eu^(3+)(M=Al,P)phosphors via partial substitution of Si^(4+) for applications in white light-emitting diodes

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Rare Metals 2024年第2期43卷 736-748页

作者： Yu-Hao Ma Xi Gao wen-Tao Zhang Zhen-Rui Yang Zhou Zhao Chen qu College of Materials and Chemistry and Chemical Engineering Chengdu University of TechnologyChengdu610059China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China International Advanced Energy Science Research and Education Center Graduate School of Energy ScienceKyoto UniversityYoshida-HonmachiKyoto606-8501Japan

A red-emitting phosphor Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) with partial Al^(3+)/P^(5+) substitution on Si^(4+) was synthesized via a simple solid-state method,and the effects of the introduction of the M^(3+/5+)(M=Al,P)ions on the crystal structure and photoluminescence performance of Ca_(2.91)Si_(2−x)M_(x)O_(7):0.09Eu^(3+) phosphors were *** X-ray diffraction(XRD),energy-dispersive X-ray spectroscopy(EDS),and X-ray photoelectron spectroscopy(XPS)results revealed that the structure of Ca_(3)Si_(2)O_(7) remained the same after the introduction of Al^(3+) and P^(5+) *** characteristic emission of Eu^(3+)-doped Ca_(3)Si_(2−x)M_(x)O_(7) phosphors exhibited two main peaks at 617 nm(red)and 593 nm(orange)under excitation at 394 nm,which originated from the^(5)D_(0)→^(7)F_(2)and^(5)D_(0)→^(7)F_(1) electron transitions of Eu^(3+) *** the partial substitution of Al^(3+) and P^(5+),the red emission intensities of the Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) phosphors were significantly enhanced by 1.88-and 1.42-fold,respectively,which is attributed to the crystal-field effect around Eu^(3+).Meanwhile,the luminescence intensities of the Ca_(2.91)Si_(1.96)Al_(0.04)O_(7):0.09Eu^(3+) and Ca_(2.91)Si_(1.94)P_(0.06)O_(7):0.09Eu^(3+) phosphors at 210℃ were 79.36%and 77.53%of those at 30°C,respectively,indicating their excellent thermal ***,the as-prepared Ca_(2.91)Si_(1.96)Al_(0.04)O_(7):0.09Eu^(3+)and Ca_(2.91)Si_(1.94)P_(0.06)O_(7):0.09Eu^(3+) red-emitting phosphors were combined with a near-ultraviolet chip of 395 nm to fabricate red-light-emitting diode(LED)and white(w)-LED devices with excellent chromaticity *** summary,Al^(3+)/P^(5+)-substituted Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) can serve as red-emitting phosphors for applications in w-LEDs.

关键词： Ca_(3)Si_(2)O_(7) Red-emitting phosphor Structure substitution Luminescence enhancement Crystal-field effect white light-emitting diode

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Microscopic Analysis of Cementitious Sand and Gravel Damming Materia

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Fluid Dynamics & Materials Processing 2024年第4期20卷 749-769页

作者： Ran wang Aimin Gong Shanqing Shao Baoli qu Jing Xu Fulai wang Feipeng Liu College of water Conservancy Yunnan Agricultural UniversityKunming650201China Tianqi Engineering Consulting Co. Ltd.Kunming650000China Institute of International Rivers and Ecological Security Yunnan UniversityKunming650500China

The mechanical properties of cementitious sand and gravel damming material have been experimentally determined by means of microscopic SEM(Scanning Electron Microscopy)image *** results show that the combination of fly ash and water can fill the voids in cemented sand and gravel test blocks because of the presence of hydrated calcium silicate and other substances;thereby,the compactness and mechanical properties of these materials can be greatly *** every 10 kg/m^(3) increase in the amount of cementitious material,the density increases by about 2%,and the water content decreases by 0.2%.The amount of cementitious material used in the sand and gravel in these tests was 80-110 kg/m^(3),the water-binder ratio was ***,the splitting tensile strength was 1/10 of the compressive strength,and the maximum strength was 7.42 MPa at 90 *** optimal mix ratio has been found to be 50 kg of cement,60 kg of fly ash and 120 kg of water(C50F60w120).The related dry density was 2.6 g/cm^(3),the water content was 6%,and the water-binder ratio was 1.09.

关键词： Cementitious sand gravel material scanning electron microscopy optimal mix ratio maximum strength

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Fli1 acts in parallel with Pu.1 to control macrophage and neutrophil fate in zebrafish

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Journal of Genetics and Genomics 2024年第3期51卷 359-362页

作者： Ao Zhang Jingao Lu Shachuan Feng Huapeng Yu Tao Yu Shizheng Zhao Kemin Chen Zhibin Huang Jin Xu Jianan Y.qu Zilong wen Division of Life Science Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Division of Cell Developmental and Integrative BiologySchool of MedicineSouth China University of TechnologyGuangzhouGuangdong 510006China Department of Immunology and Microbiology School of Life ScienceSouthern University of Science and TechnologyShenzhenGuangdong 518055China Biomedical Research Institute Shenzhen Peking University-Hong Kong University of Science and Technology Medical CenterShenzhenGuangdong 518036China Department of Electronic and Computer Engineering Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Greater Bay Biomedical Innocenter Shenzhen Bay LaboratoryShenzhenGuangdong 518067China

Macrophages and neutrophils are key components of myeloid cells and play critical roles in innate immune responses,organ formation,and tissue *** integrity of their functions heavily relies on the generation of a proper number of mature macrophages and neutrophils through embryonic and adult *** mammalian adult myelopoiesis,oligopotent common myeloid progenitors(CMPs)are known to be the earliest myeloid progenitors,which give rise to granulocyte-macrophage progenitors(GMPs),subsequently differentiate into unipotent neutrophil and macrophage precursors,and finally,mature macrophages and neutrophils(Orkin and Zon,2008).In contrast,the ontogeny of embryonic myelopoiesis and the mechanism underlying the formation of macrophages and neutrophils remainless understood.

关键词： fish macrophage homeostasis

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Enhanced photothermal dehydration of methanol over w_(18)O_(49)/Au/SAPO-34 catalysts with broadened light absorption

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Rare Metals 2024年第3期43卷 1139-1152页

作者： Ya-Qin Tang Meng-Xia Yan Chang-Qian Lu Shao-Yuan Li Kui-Xian wei Tao qu wen-HuiMa Yong-Nian Dai Kong-Zhai Li Da-Jun Luo Xue-Liang Zhang Yi-Ke Liu Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming650093China School of Materials and Energy Engineering Guizhou Institute of TechnologyGuiyang550003China

Methanol-to-olefins(MTO)process is one of the most critical pathways to produce low carbon ***,the reaction is driven by thermal catalysis,which inevitably needs to consume large amounts of fossil *** a new technique to substitute for the fuel burning is urgent for MTO process to improve the industry prospects and ***,we report a novel w_(18)O_(49)/Au/SAPO-34(w/Au/S),a multifunctional photothermal catalyst for the MTO reaction.A high methanol conversion was achieved under xenonum(Xe)lamp irradiation,yielding methyl ether(ME)and ethylene as the main *** optimized w/Au/S catalysts showed ethylene yield as high as 250μmol in 60 min,which was 2.5 times higher than that of Au/*** physiochemical characterization revealed that the SAPO-34 molecular sieves were surrounded by Au and w_(18)O_(49)nanoparticles,which exhibited a strong localized surface plasmon resonance excitation around 540 nm and light absorption beyond 500 *** multifunctional catalysts showed a strong photothermal effect,arising from the broadened light absorption of Au and w_(18)O_(49)nanoparticles,leading to a temperature as high as 250℃on the surface of the *** study showed that the superior ethylene selectivity of w/Au/S catalysts was attributed to the moderating acidic sites of w_(18)O_(49)for methanol dehydration to *** research may provide new insight for designing heterostructures to improve photo-to-chemical conversion performance and is expected to accelerate progress toward the excellent multifunctional photothermal catalysts with broad light absorption for methanol activation and C-C bond formation.

关键词： Methanol conversion Ethylene Photothermal catalysis w_(18)O_(49) BrΦnsted-acid

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瞬态热流下钨初级裂纹对脉宽时间的依赖性研究

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核聚变与等离子体物理 2024年第2期44卷 206-213页

作者：屈苗颜莎中核战略规划研究总院北京100048 北京大学重离子物理研究所北京100871

为了研究钨在瞬态热流下的开裂行为对热源参数时间分布的依赖关系,采用了三种脉宽t(80ns、1ms、5ms)的瞬态热流,在不同能量密度E不同脉冲次数下辐照纯钨样品,在钨表面观察到初级和次级两种裂纹。初级裂纹呈现枝状和网状两种形态。通过... 详细信息

为了研究钨在瞬态热流下的开裂行为对热源参数时间分布的依赖关系,采用了三种脉宽t(80ns、1ms、5ms)的瞬态热流,在不同能量密度E不同脉冲次数下辐照纯钨样品,在钨表面观察到初级和次级两种裂纹。初级裂纹呈现枝状和网状两种形态。通过分析初级裂纹特征量发现,不同脉宽的热脉冲导致的表面温升相近时,脉宽越短而初级裂纹密度越大。考虑钨的韧脆转变特性,建立了基于理想弹塑性力学模型的热力学有限元计算模型,用该模型计算了钨在三种脉宽的热脉冲辐照下表层温度与应力的分布及演化。分析发现脉宽变化引起的应变率量级差异,将反映到材料的力学性能上,使得脉宽越短而材料脆性越强,从而引起初级裂纹特征的变化。结合实验与计算结果,提出了用Et‒3/2衡量在脉宽百ns量级到ms量级的热脉冲辐照下初级裂纹网密度的相对大小。

关键词：钨瞬态热流初级裂纹密度脉宽时间有限元分析

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新生儿肠沙门菌肠道亚种沃兴顿株引起血流感染1例

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中华检验医学杂志 2024年第2期47卷 184-186页

作者：屈龙凤张亚运重庆大学附属江津医院检验科重庆402260 重庆市江津区中医院检验科重庆402260

患儿女,出生6 d 19 h,以“皮肤黄染3 d,发热6 h”于2023年3月31日就诊于重庆大学附属江津医院。4月1日报告血培养危急值:革兰阴性杆菌,经质谱及生化经鉴定为沙门菌属,血清型AF多价(-),Vi(-),考虑为非A~F群沙门菌。传代培养后血清凝集试... 详细信息

患儿女,出生6 d 19 h,以“皮肤黄染3 d,发热6 h”于2023年3月31日就诊于重庆大学附属江津医院。4月1日报告血培养危急值:革兰阴性杆菌,经质谱及生化经鉴定为沙门菌属,血清型AF多价(-),Vi(-),考虑为非A~F群沙门菌。传代培养后血清凝集试验结果为:O13,23 Hz,l,w,利用16S rRNA和gyrB基因测序鉴定为肠沙门菌肠道亚种沃兴顿株,与血清学试验相符。患儿经氨苄西林舒巴坦抗感染治疗14 d后病情好转出院。沙门菌鉴定需同时进行细菌生化鉴定和血清学试验,以保证检测准确性,为临床提供可靠的病原学诊断依据。

关键词：沙门菌属血清分型血流感染

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PCCL光束对瑞利粒子作用力的理论研究

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激光技术 2024年第05期48卷 698-704页

作者：谢陈屈军安徽师范大学物理与电子信息学院

为了探究部分相干月牙形光束（PCCL）对瑞利粒子的捕获特性，采用广义惠更斯-菲涅耳原理推导了PCCL光束经过ABCD光学系统传输后的交叉谱密度及对瑞利粒子作用力的表达式，对聚焦PCCL光束在焦平面的归一化光强和对瑞利粒子作用力的分布... 详细信息

为了探究部分相干月牙形光束（PCCL）对瑞利粒子的捕获特性，采用广义惠更斯-菲涅耳原理推导了PCCL光束经过ABCD光学系统传输后的交叉谱密度及对瑞利粒子作用力的表达式，对聚焦PCCL光束在焦平面的归一化光强和对瑞利粒子作用力的分布情况进行了软件模拟和理论分析，得到了聚焦PCCL光束的光强和捕获力随光束参量以及焦距变化的规律。结果表明，选取光束阶数n=3、初始腰宽w0=0.1 mm、相干长度d0=6 mm时，经焦距f=12 mm的透镜聚焦后的PCCL光束对高、低折射率粒子均能实现捕获；由于PCCL光束在焦平面处呈现离轴光强分布，峰值光强不在坐标原点，通过调节光束阶数、初始腰宽、相干长度和焦距，可实现对聚焦PCCL光强及瑞利粒子作用力的调控，从而实现聚焦PCCL光束对不同位置处瑞利粒子的灵活捕获。该研究结果为实际聚焦PCCL光束稳定捕获微粒提供了理论依据。

关键词：激光光学聚焦捕获惠更斯-菲涅耳原理部分相干月牙形光束

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Farnesyltransferase inhibitor lonafarnib suppresses respiratory syncytial virus infection by blocking conformational change of fusion glycoprotein

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2970-2983页

作者： Qi Yang Bao Xue Fengjiang Liu Yongzhi Lu Jielin Tang Mengrong Yan Qiong wu Ruyi Chen Anqi Zhou Lijie Liu Junjun Liu Changbin qu Qingxin wu Muqing Fu Jiayi Zhong Jianwei Dong Sijie Chen Fan wang Yuan Zhou Jie Zheng wei Peng Jinsai Shang Xinwen Chen Guangzhou National Laboratory Guangzhou 510005China State Key Laboratory of Respiratory Disease Guangzhou Medical UniversityGuangzhou 511436China wuhan Institute of Virology Chinese Academy of SciencesWuhan 430071China School of Basic Medical Sciences Guangzhou Medical UniversityGuangzhou 511436China GMUGIBH Joint School of Life Sciences Guangzhou Medical UniversityGuangzhou 511436China Guangzhou Institutes of Biomedicine and Health Chinese Academy of SciencesGuangzhou 510530China Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai 201203China School of Pharmaceutical Science and Technology Hangzhou lnstitute for Advanced StudyUCASHangzhou 310024China

Respiratory syncytial virus(RSV)is the major cause of bronchiolitis and pneumonia in young children and the *** are currently no approved RSV-specific therapeutic small molecules *** high-throughput antiviral screening,we identified an oral drug,the prenylation inhibitor lonafarnib,which showed potent inhibition of the RSV fusion *** exhibited antiviral activity against both the RSV A and B genotypes and showed low cytotoxicity in HEp-2 and human primary bronchial epithelial cells(HBEC).Time-of-addition and pseudovirus assays demonstrated that lonafarnib inhibits RSV entry,but has farnesyltransferase-independent antiviral ***-electron microscopy revealed that lonafarnib binds to a triple-symmetric pocket within the central cavity of the RSV F metastable pre-fusion *** at the RSV F sites interacting with lonafarnib showed resistance to lonafarnib but remained fully sensitive to the neutralizing monoclonal antibody ***,lonafarnib dose-dependently reduced the replication of RSV in BALB/c ***,lonafarnib could be a potential fusion inhibitor for RSV infection.

关键词： neutral metastable approved

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基于氮化镓的反激同步整流DC/DC变换器设计

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电源学报 2024年第2期22卷 81-89页

作者：佟强刘贺曲璐深圳信息职业技术学院智能制造与装备学院深圳518172

给出了一种适合低轨商用航天的中小功率DC/DC变换器的设计方法。该方法采用了反激同步整流拓扑和表贴器件,可以覆盖常见的航天用中小功率单路及多路输出DC/DC变换器需求,具备低成本、高性能、高可靠、可批量化生产的优点。为了进一步提... 详细信息

给出了一种适合低轨商用航天的中小功率DC/DC变换器的设计方法。该方法采用了反激同步整流拓扑和表贴器件,可以覆盖常见的航天用中小功率单路及多路输出DC/DC变换器需求,具备低成本、高性能、高可靠、可批量化生产的优点。为了进一步提高转换效率和功率密度,还应用了氮化镓GaN(gallium nitride)功率开关。并且对不同工作条件下拓扑中主要功率器件的损耗进行了计算和对比分析。最后,以一款宽输入电压范围(23~47 V),输出5 V@30 w的电源变换器为例对所提方法进行了验证。

关键词：变换器氮化镓反激同步整流商用航天

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Effect of ground cover changes on solar radiation absorption in Three Northeastern Provinces of China

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地球环境学报 2024年第4期15卷 675-690页

作者： SHUAI Yanmin CHEN Yangyang SHAO Congying TIAN Yanjun qu Ge HUANG Jiapeng School of Geomatics Liaoning Technical UniversityFuxin 123000China Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China CAS Research Center for Ecology and Environment of Central Asia Urumqi 830011China College of Geography and Environmental Sciences Zhejiang Normal UniversityJinhua 321004China

Background,aim,and scope Solar radiation is the main source of energy for terrestrial *** changes in the absorption of solar radiation at the ground surface can have a significant impact on the climatic *** and anthropogenic changes in ground cover are important factors affecting the absorption of solar radiation at the ground *** phenomenon is particularly pronounced in the mid and high *** order to quantify the inf luence of surface cover change on the absorption of solar radiation at the surface and to provide a scientific basis for changes in the climatic environment,this paper analyzed ground cover change,ground absorbed solar radiation change and the effect of ground cover change on ground absorbed solar radiation in the Three Northeastern Provinces of China from 2001 to *** and methods In this study,the Three Northeastern Provinces of China were used as the study ***,satellite remote sensing data were used to obtain land cover data and albedo data for Aug.1st of each year in 2001,2005,2010,2015 and *** albedo data were further used to calculate the absorbed solar radiation data at the ground ***,the land cover data were used to count the area changes and shifts of different land classes over the five-year *** land cover data were overlaid with the surface absorbed solar radiation data to obtain the mean and standard deviation of radiation absorption for different ground *** surface absorbed solar radiation data were subtracted to obtain the changes in surface absorbed solar radiation for 2001-2005,2005-2010,2010-2015 and ***,we used a combination of shifted changes in ground classes and changes in surface absorbed solar radiation data,with unchanged ground classes as a baseline and data such as slope orientation as an *** analyzed the effect of ground cover change on surface absorbed solar radiation at regional and pixel point ***(1)T

关键词： land surface cover changes surface absorption of solar radiation the Three Northeastern Provinces albedo

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