检索结果-南通市图书馆

Luminescence properties and optical sensing behaviors of Sr_(2)GdSbO_(6):Eu^(3+) phosphors

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第8期42卷 1458-1469,I0002页

作者： Youfa Tai Ruirui Cui jun zhang Chunkai Wang Tingyu Zhao Beiqiao zhang Chaoyong deng Key Laboratory of Functional Composite Materials of Guizhou Province College of Big Data and Information EngineeringGuizhou UniversityGuiyang550025China College of Computer and Information Engineering Guizhou University of CommerceGuiyang550014China School of Electronics and Information Engineering Guiyang UniversityGuiyang550005China

Novel orange-red Sr_(2)GdSbO_(6):xEu^(3+)(x=0,0.05,0.1,0.2,0.3,0.4,0.5 and 0.6) phospho rs were successfully prepared by the traditional high-temperature solid-state *** results of Rietveld refinement,energy dispersive spectroscopy(EDS) spectrum and elemental mapping demonstrate that Eu^(3+) successfully replaces the Gd^(3+) sites and distributes uniformly in the particles of *** luminescence properties of Sr_(2)GdSbO_(6):Eu_(3+)phosphors were investigated in *** emission spectra of the strongest emission peak is the ^(5)D_(0)→^(7)F_(1)(593 nm) transition,which can emit orange-red light under393 nm *** the doping concentration of Eu3+ions is x=0.2,the luminescence intensity of the phosphors reaches the *** detailed mechanism of concentration quenching is attributed to dipole-dipole *** thermal stability values of Sr_(2)GdSbO_(6):0.2Eu^(3+) phosphors are 87%,82% and114% under 393,467 and 527 nm excitations,*** causes of the abnormal thermal quenching under 527 nm excitation were *** on the abnormal thermal quenching under527 nm excitation,the optical thermometry properties of Sr_(2)GdSbO_(6):0.2Eu^(3+)phosphors were investigated by fluorescence intensity ratio(FIR) technique,and appreciable relative sensitivity was *** results suggest that Sr_(2)GdSbO_(6):0.2Eu^(3+)phosphors can be potentially applied to w-LEDs and optical thermometers.

关键词： Sr_(2)GdSbO_(6):Eu^(3+) Phosphors Luminescence properties Abnormal thermal quenching Rare earths

单侧双通道内镜技术治疗腰椎间盘突出症的疗效及去骨量分析

在线全文

学校读者我要写书评

暂无评论

中国骨伤 2024年第3期37卷 222-227页

作者：莘清云李文正韩钧鉴刘启涛冯超郭秀生魏杰宋洁富秦德安张登君山西医科大学第五临床医学院山西省人民医院骨科山西太原030029

目的:比较单侧双通道内镜(unilateral biportal endoscopic,UBE)和椎板小开窗术式治疗腰椎间盘突出症(lumbar disc herniation,LDH)的临床疗效及骨去除量。方法:回顾性分析2019年12月至2021年12月收治的105例单节段LDH患者,其中54例接受... 详细信息

目的:比较单侧双通道内镜(unilateral biportal endoscopic,UBE)和椎板小开窗术式治疗腰椎间盘突出症(lumbar disc herniation,LDH)的临床疗效及骨去除量。方法:回顾性分析2019年12月至2021年12月收治的105例单节段LDH患者,其中54例接受UBE治疗(UBE组),男32例,女22例,年龄18~50(38.7±9.3)岁;L4-529例,L5S125例。51例接受椎板小开窗术式治疗(椎板小开窗组),男27例,女24例,年龄18~50(39.9±10.0)岁;L4,525例,L5S126例。观察并比较两组手术时间、术后下床时间、住院时间等围手术期指标,分别于术前和术后1、3、6、12个月比较两组腰腿痛视觉模拟评分(visual analogue scale,VAS)、Oswestry功能障碍指数(Oswestry disability index,ODI),并采用改良MacNab标准进行临床疗效评价。比较两组下关节突椎板复合体骨去除量和保留率。结果:105例患者均顺利完成手术。两组均获得随访,时间6~12(10.69±2.49)个月。UBE组手术时间、术后下床时间、住院时间分别为(58.20±5.54)min、(2.40±0.57)d、(3.80±0.61)d,椎板小开窗组分别为(62.90±7.14)min、(4.40±0.64)d、(4.40±0.64)d,两组比较,差异有统计学意义(P0.05)。末次随访时根据改良MacNab标准,UBE组优49例,良3例,可2例;椎板小开窗组中优35例,良12例,可4例,两组比较,差异有统计学意义(χ2=8.321,P<0.05)。UBE组下关节突椎板复合体骨去除量为L4,5节段(0.45±0.08)cm3、L5S1节段(0.31±0.08)cm3;椎板小开窗组L4,5节段(0.57±0.07)cm3、L5S1节段(0.49±0.04)cm3,同一节段UBE组下关节突椎板复合体骨去除量少于椎板小开窗组(P<0.05)。UBE组下关节突椎板复合体保留率为L4,5节段(0.73±0.04)、L5S1节段(0.83±0.03);椎板小开窗组L4,5节段(0.68±0.06),L5S1节段(0.74±0.04),同一节段UBE组下关节突椎板复合体保留率高于椎板小开窗组(P<0.05)。结论:UBE技术与椎板小开窗术治疗LDH均能达到良好的临床效果,但UBE具有创伤更小、效率更高、术后恢复更快及对骨性结构破坏更小等优势。

关键词：单侧双通道腰椎间盘突出症微创外科手术

Asymptotic Inference in the Random Coefficient Autoregressive Model with Time-functional Variance Noises

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2024年第2期40卷 320-346页

作者： En-wen ZHU Zi-wei deng Han-jun zhang jun CAO Xiao-hui LIU Department of Mathematics and Statistics Changsha University of Science and TechnologyChangsha 410114China School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105China School of Statistics and Data Science and Key Laboratory of Data Science in Finance and EconomicsJiangxi University of Finance and EconomicsNanchang 330013China

This paper considers the random coefficient autoregressive model with time-functional variance noises,hereafter the RCA-TFV *** first establish the consistency and asymptotic normality of the conditional least squares estimator for the constant *** semiparametric least squares estimator for the variance of the random coefficient and the nonparametric estimator for the variance function are constructed,and their asymptotic results are reported.A simulation study is presented along with an analysis of real data to assess the performance of our method in finite samples.

关键词： random coefficient autoregressive model time-functional variance conditional least squares semiparametric least squares

Aerodynamic/stealth design of S-duct inlet based on discrete adjoint method

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 725-746页

作者： jun deng Ke ZHAO Lin ZHOU Wei zhang Bowen SHU Jiangtao HUANG Zhenghong GAO School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Aerospace Technology Institute of China Aerodynamic Research and Development CenterMianyang 621000Sichuan ProvinceChina

It is a major challenge for the airframe-inlet design of modern combat aircrafts,as the flow and electromagnetic wave propagation in the inlet of stealth aircraft are very *** this study,an aerodynamic/stealth optimization design method for an S-duct inlet is *** upwind scheme is introduced to the aerodynamic adjoint equation to resolve the shock wave and flow *** multilevel fast multipole algorithm(MLFMA)is utilized for the stealth adjoint equation.A dorsal S-duct inlet of flying wing layout is optimized to improve the aerodynamic and stealth *** the aerodynamic and stealth characteristics of the inlet are effectively ***,the optimization results are analyzed,and it shows that the main contradiction between aerodynamic characteristics and stealth characteristics is the centerline and crosssectional *** S-duct is smoothed,and the cross-sectional area is increased to improve the aerodynamic characteristics,while it is completely opposite for the stealth *** radar cross section(RCS)is reduced by phase cancelation for low frequency *** method is suitable for the aerodynamic/stealth design of the aircraft airframe-inlet system.

关键词： S-duct inlet aerodynamic/stealth optimization design discrete adjoint upwind scheme multilevel fast multipole algorithm(MLFMA)

Theoretical study on the effect of H_(2)O on the formation mechanism of NO_(x) precursors during indole pyrolysis

在线全文

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and Engineering 2024年第6期18卷 99-112页

作者： Ziqi Wang jun Shen Xuesong Liu Sha Wang Shengxiang deng Hai zhang Yun Guo School of Mechanical and Automotive Engineering Shanghai University of Engineering ScienceShanghai 201620China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The incineration technology of kitchen waste is one of the effective technologies to achieve the resource utilization of municipal solid *** is an important stage of *** is a rich initial product in the pyrolysis process of kitchen waste,and the presence of H_(2)O has a significant impact on the decomposition of indole to form NO_(x) ***,this study uses density functional theory method to study the effect of H_(2)O on the thermal decomposition of indole to produce NH_(3),HNCO,and *** H_(2)O participates in the reaction,it can provide oxidative groups to generate a new product HNCO,which is different from the previous findings by indole pyrolysis without the presence of H_(2)***,this study theoretically proves that NH_(3) is easier to form than *** is consistent with the phenomenon that NH_(3) release is higher than HCN release in pyrolysis *** addition,compared with the individual pyrolysis of indole,the participation of H_(2)O reduces the energy barriers for the formation of NH_(3) and HCN during indole pyrolysis,thereby promoting the formation of NH_(3) and HCN.

关键词： indole pyrolysis H_(2)O NO_(x)precursors DFT

Geology and genesis of the Aqishan Pb-Zn deposit,NW China:Insights from mineralogy,geochemistry,and in situ U-Pb geochronology

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geoscience Frontiers 2024年第5期15卷 489-514页

作者： Kang Wang Yinhong Wang jun deng Jiajun Liu Fangfang zhang Wei zhang Hui zhang Wenxin Gu Hong Chen State Key Laboratory of Geological Processes and Mineral Resources and School of Earth Sciences and ResourcesChina University of GeosciencesBeijing 100083China

The unique ore-forming processes and the key factors responsible for formation of skarn deposits are still obscure,and challenges exist in the determination of timing of Pb-Zn skarns owing to lacking suitable mineral *** we present detailed paragenesis,bulk geochemistry,in situ U-Pb dating of zircon and garnet,and garnet oxygen isotopes together with in situ zircon Hf-O isotopes from the newly discovered Aqishan Pb-Zn deposit in the southern Central Asian Orogenic Belt(CAOB),northwest *** comprehensive data set revealed a Late Carboniferous subduction-related distal Pb-Zn skarn system associated with the granitic ***-ore stage garnets are generally subhedral to euhedral with oscillatory zoning and show slightly fractionated rare earth element patterns with positive Eu anomalies that point to an infiltration metasomatism origin under high water/rock *** syn-ore stage sphalerite is typically enriched in Mn and Cd and has moderate Zn/Cd ratios(337–482),with a formation temperature of 265℃to 383℃,which indicate magmatic-hydrothermal *** isocons defined by P_(2)O_(5)decipher that the principal factors for skarn formation were elevated activities of Fe,Ca,and Si species,where remobilization of Pb metals,meanwhile,contributed to ore-forming budgets to mineralizing *** U-Pb dating of zircons from granite porphyry that occurs distal to the skarns and Pb-Zn orebodies shows that these intrusions emplaced at ca.311.3–310.6 Ma,recording the subduction of the Paleo-Tianshan oceanic *** garnets in close textural association with Pb-Zn sulfides yield indistinguishable in situ LA-ICP-MS U-Pb ages of 310.5±4.1 ***-rock geochemistry and in situ zircon Hf-O isotopes(δ^(18)O=4.6‰–6.0‰)indicate that the granite porphyry was derived from partial melting of juvenile crust and influenced by subducted oceanic *** isotope compositions of garnets(δ^(18)O=8.0‰–9.0‰)demonstrate that the equilibrated ore fluids

关键词： In situ U-Pb dating Garnet O isotopes Aqishan Pb-Zn deposit Skarn mineralization Southern CAOB

Multi-junction cascaded vertical-cavity surface-emitting laser with a high power conversion efficiency of 74%

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Light(Science & Applications) 2024年第3期13卷 555-565页

作者： Yao Xiao jun Wang Heng Liu Pei Miao Yudan Gou Zhicheng zhang Guoliang deng Shouhuan Zhou College of Electronics and Information Engineering Sichuan UniversityChengdu 610064China Suzhou Everbright Photonics Co. LtdSuzhou 215163China

High electro-optical conversion efficiency is one of the most distinctive features of semiconductor lasers as compared to other types of *** further increase remains a significant *** enhancing the efficiency of edgeemitting lasers(EEL),which represent the highest efficiency among semiconductor lasers at present,is *** efficiency of vertical cavity surface emitting lasers(VCSELs)has always been relatively low compared to *** paper,combining modeling with experiments,demonstrates the potential of multi-junction cascaded VCSELs to achieve high efficiency beyond that of EELs,our simulations show,that a 20-junction VCSEL can achieve an efficiency of more than 88%at room *** fabricated VCSEL devices with different numbers of junctions and compared their energy efficiency.15-junction VCSELs achieved a maximum efficiency of 74%at room temperature under nanosecond driving current,the corresponding differential quantum efficiency exceeds 1100%,being the largest electro-optical conversion efficiency and differential quantum efficiency reported until now for VCSELs.

关键词： cascaded power cavity

A review on graphite surface modification methods towards low carbon-containing refractories

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 Iron and Steel Research International 2024年第6期31卷 1291-1303页

作者： Ting-ting zhang jun Ding Bei-yue Ma Zheng-long Liu Chao Yu Cheng-ji deng The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

The rapid development of iron and steel metallurgy technology has promoted the continuous innovation and iteration of carbon-containing refractories for clean steel *** meet the high-quality requirements for clean steel production and full exploit the performance advantages of carbon-containing refractories in dynamic smelting environment,it is necessary to explore the role of graphite and modified graphite in carbon-containing *** on this,graphite surface modification methods,including surfactants,surface oxidation,and surface coating,and their applications in carbon-containing refractories are *** advantages and disadvantages of each method are analyzed for practical ***,combined with the existing problems,the application prospect of improved graphite in carbon-containing refractories is discussed.

关键词： Graphite Carbon-containing refractory Clean steel Surface modification Service performance

A write buffer design based on stable and area-saving embedded SRAM for flash applications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2015年第2期58卷 357-361页

作者： CAO Hua Min HUO Zong Liang WANG Yu LI Ting LIU Jing JIN Lei JIANG Dan-Dan zhang deng jun LI Di LIU Ming Institute of Microelectronics Chinese Academy of Sciences College of Communication Engineering Chengdu University of Information Technology Guangdong Berg Micro Co. Ltd.

This paper presents an embedded SRAM design for write buffer applications in flash *** write buffer is implemented with a newly proposed self-adaptive timing control circuit,an area-saving sense-latch circuit and 6 T SRAM cell units.A 2 kb SRAM macro with the area of 135μm×180μm is implemented in and applied to a 128 Mb NOR flash memory with the SMIC 65 nm NOR flash memory *** simulation and chip test results show that the SRAM write buffer is beneficial to high-density flash memory design.

关键词： write buffer embedded SRAM flash 65 nm technology 2 kb 128 Mb