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Modelling and analysis of metal flowing behaviors in constraining ring rolling of tapered ring with thin wall and three high ribs 被引量:3
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作者 Lin HUA Duanyang TIAN +1 位作者 Xinghui HAN Wuhao ZHUANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第6期476-492,共17页
Tapered ring with thin wall and three high ribs(TRTWTHR),showing complicated geometry(wall thickness is less than 4 mm and rib height exceeds 20 mm),is extensively utilized to fabricate the critical structural parts o... Tapered ring with thin wall and three high ribs(TRTWTHR),showing complicated geometry(wall thickness is less than 4 mm and rib height exceeds 20 mm),is extensively utilized to fabricate the critical structural parts of aerospace equipment such as spacecraft cabin,rocket body and fuel tank because of light weight and high carrying capacity.How to fabricate TRTWTHR with high performance is a critical problem that aerospace area needs to solve.In this work,constraining ring rolling(CRR)technique is first adopted to form TRTWTHR.However.unreasonable metal streamlines(UMS)and uncoordinated growth of three ribs easily occur in CRR of TRTWTHR,which makes the forming quality of TRTWTHR difficult to be controlled.Faced with this difficulty,an analytical model that can predict UMS and the height of three ribs in CRR of TRTWTHR is established so as to guide the process design of CRR.Subsequently,the reliability of the established analytical model and the feasibility of CRR of TRTWTHR are confirmed by FE simulation and experiment.Then,using the established analytical model,the window of UMS occurring relevant to the tapered angle of TRTWTHR and the location of the rib of middle end is developed.Finally,three uncoordinated growth modes among three ribs are found when the width of three ribs is identical and UMS do not occur,and the mechanisms of three uncoordinated growth modes are revealed. 展开更多
关键词 Analytical model Constraining ring rolling Growth of three ribs Metal streamlines Tapered ring with thin wall and three high ribs
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Three-dimensional simulation method of multipactor in microwave components for high-power space application 被引量:5
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作者 李韵 崔万照 +4 位作者 张 娜 王新波 王洪广 李永东 张剑锋 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第4期686-693,共8页
Based on the particle-in-cell technology and the secondary electron emission theory, a three-dimensional simulation method for multipactor is presented in this paper. By combining the finite difference time domain met... Based on the particle-in-cell technology and the secondary electron emission theory, a three-dimensional simulation method for multipactor is presented in this paper. By combining the finite difference time domain method and the panicle tracing method, such an algorithm is self-consistent and accurate since the interaction between electromagnetic fields and particles is properly modeled. In the time domain aspect, the generation of multipactor can be easily visualized, which makes it possible to gain a deeper insight into the physical mechanism of this effect. In addition to the classic secondary electron emission model, the measured practical secondary electron yield is used, which increases the accuracy of the algorithm. In order to validate the method, the impedance transformer and ridge waveguide filter are studied. By analyzing the evolution of the secondaries obtained by our method, multipactor thresholds of these components are estimated, which show good agreement with the experimental results. Furthermore, the most sensitive positions where multipactor occurs are determined from the phase focusing phenomenon, which is very meaningful for multipactor analysis and design. 展开更多
关键词 MULTIPACTOR numerical method three-DIMENSIONAL high-POWER THRESHOLD
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High-capacity three-party quantum secret sharing with superdense coding 被引量:2
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作者 顾斌 李传起 +1 位作者 徐飞 陈玉林 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第11期4690-4694,共5页
This paper presents a scheme for high-capacity three-party quantum secret sharing with quantum superdense coding, following some ideas in the work by Liuet al (2002 Phys. Rev. A 65 022304) and the quantum secret sha... This paper presents a scheme for high-capacity three-party quantum secret sharing with quantum superdense coding, following some ideas in the work by Liuet al (2002 Phys. Rev. A 65 022304) and the quantum secret sharing scheme by Deng et al (2008 Phys. Lett. A 372 1957). Instead of using two sets of nonorthogonal states, the boss Alice needs only to prepare a sequence of Einstei^Podolsky-l^osen pairs in d-dimension. The two agents Bob and Charlie encode their information with dense coding unitary operations, and security is checked by inserting decoy photons. The scheme has a high capacity and intrinsic efficiency as each pair can carry 21bd bits of information, and almost all the pairs can be used for carrying useful information. 展开更多
关键词 quantum secret sharing three-party high-CAPACITY superdense coding
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Oxidation behavior of three-phase Cu-25Ni-30Cr alloy at 700-800℃ under high oxygen pressures 被引量:1
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作者 曹中秋 刘伟华 +5 位作者 翟广平 牛焱State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China 《中国有色金属学会会刊:英文版》 CSCD 2005年第3期491-496,共6页
The thermogravimetric analysis of a ternary Cu-25Ni-30Cr alloy prepared by conventional casting was performed in 0.1MPa pure O2 at 700-800℃. The results show that the alloy is composed of three phases, where the phas... The thermogravimetric analysis of a ternary Cu-25Ni-30Cr alloy prepared by conventional casting was performed in 0.1MPa pure O2 at 700-800℃. The results show that the alloy is composed of three phases, where the phase with the largest copper and lowest chromium content forms the matrix, while the other two, much richer in chromium, form a dispersion of isolated particles. At variance with another three-phase Cu-20Ni-20Cr alloy, which forms complex scales containing the oxides of the various components and double oxides plus an irregular region composed of alloy and oxides, the present alloy can form a very irregular but continuous chromia layer at the base of the mixed internal region, producing a gradual decrease of the oxidation rate down to very low values. A larger chromium content needed to form chromia layer for a ternary three-phase alloy is attributed to the limitations to the diffusion of the alloy components in the metal substrate imposed by their multiphase nature. 展开更多
关键词 铜-镍-铬合金 三相 高温氧化 热解重量
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Progress and Development Direction of “Three-High” Oil and Gas Well Testing Technology 被引量:2
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作者 Bo Zhang Fayon Yuan +3 位作者 Hao Su Ming Cao Ruifeng Guo Chenxiang Sun 《Journal of Power and Energy Engineering》 2022年第6期1-13,共13页
By reviewing the development of “three-high” oil and gas well testing technology of Sinopec in recent years, this paper systematically summarizes the application of “three-high” oil and gas well testing technology... By reviewing the development of “three-high” oil and gas well testing technology of Sinopec in recent years, this paper systematically summarizes the application of “three-high” oil and gas well testing technology of Sinopec in engineering optimization design technology, and high temperature and high pressure testing technology, high pressure and high temperature transformation completion integration technology. Major progress has been made in seven aspects: plug removal and re-production technology of production wells in high acid gas fields;wellbore preparation technology of ultra-deep, high-pressure, and high-temperature oil and gas wells;surface metering technology;and supporting tool development technology. This paper comprehensively analyzes the challenges faced by the “three-high” oil and gas well production testing technology in four aspects: downhole tools, production testing technology, safe production testing, and the development of low-cost production test tools. Four development directions are put forward: 1) Improve ultra-deep oil and gas testing technology and strengthen integrated geological engineering research. 2) Deepen oil and gas well integrity evaluation technology to ensure the life cycle of oil and gas wells. 3) Carry out high-end, customized, and intelligent research on oil test tools to promote the low-cost and efficient development of ultra deep reservoirs. 4) Promote the fully automatic control of the surface metering process to realize the safe development of “three-high” reservoirs. 展开更多
关键词 three-high Oil and Gas Wells Oil Test Geological Engineering Integra-tion Intelligent Downhole Tools
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Microfluidic three-dimensional cell culture of stem cells for high-throughput analysis 被引量:5
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作者 Jeong Ah Kim Soohyun Hong Won Jong Rhee 《World Journal of Stem Cells》 SCIE 2019年第10期803-816,共14页
Although the recent advances in stem cell engineering have gained a great deal of attention due to their high potential in clinical research,the applicability of stem cells for preclinical screening in the drug discov... Although the recent advances in stem cell engineering have gained a great deal of attention due to their high potential in clinical research,the applicability of stem cells for preclinical screening in the drug discovery process is still challenging due to difficulties in controlling the stem cell microenvironment and the limited availability of high-throughput systems.Recently,researchers have been actively developing and evaluating three-dimensional(3D)cell culture-based platforms using microfluidic technologies,such as organ-on-a-chip and organoid-on-a-chip platforms,and they have achieved promising breakthroughs in stem cell engineering.In this review,we start with a comprehensive discussion on the importance of microfluidic 3D cell culture techniques in stem cell research and their technical strategies in the field of drug discovery.In a subsequent section,we discuss microfluidic 3D cell culture techniques for high-throughput analysis for use in stem cell research.In addition,some potential and practical applications of organ-on-a-chip or organoid-on-a-chip platforms using stem cells as drug screening and disease models are highlighted. 展开更多
关键词 STEM CELL Microfluidic TECHNOLOGY three-DIMENSIONAL CELL CULTURE highthroughput SCREENING
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Electromagnetically induced transparency of single Λ-type three-level atoms in a high-finesse optical cavity
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作者 孙燕芬 谭磊 徐岩 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期158-162,共5页
We study the features of electromagnetically induced transparency(EIT) in a single Λ-type three-level atom placed in a high-finesse cavity under the action of a coupling laser and a probe laser.Our calculations sho... We study the features of electromagnetically induced transparency(EIT) in a single Λ-type three-level atom placed in a high-finesse cavity under the action of a coupling laser and a probe laser.Our calculations show that three transparency windows appear when the pump strength is large enough.This can be explained by the residual pump in the cavity mostly resulting in energy splitting.The level |3 is split into four slightly different energy levels,and interference takes place between the excitation pathways.Furthermore,it is also shown that the frequencies of the EIT windows can be tuned by changing the coupling field detuning 2,and that the reflection profile is very sensitive to the cavity field detuning △c. 展开更多
关键词 Λ-type three-level atom high-finesse optical cavity electromagnetically induced transparency
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Topological Studies of Three-dimensional Flows in a High Pressure Compressor Stator Blade Row without and with Boundary Layer Aspiration 被引量:3
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作者 Ankit SACHDEVA Francis LEBOEUF 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2011年第5期541-549,共9页
This paper presents a numerical study of the flow topologies of three-dimensional (3D) flows in a high pressure compressor stator blade row without and with boundary layer aspiration on the hub wall. The stator blad... This paper presents a numerical study of the flow topologies of three-dimensional (3D) flows in a high pressure compressor stator blade row without and with boundary layer aspiration on the hub wall. The stator blade is representative of the first stage operating under transonic inlet conditions and the blade design encourages development of highly complex 3D flows. The blade has a small tip clearance. The computational fluid dynamics (CFD) studies show progressive increase of hub corner stall with the increase in incidence. Aspiration is implemented on the hub wall via a slot in the comer between the hub wall and the suction surface. The CFD studies show aspiration to be sensitive to the suction flow rate; lower rate leads to very complex flow struc- tures and increased level of losses whereas higher rate renders aspiration effective for control of hub comer separation. The flow topologies are studied by trace of skin friction lines on the walls. The nature of flow can be explained by the topological rules of closed separation. Furthermore, a deeper analysis is done for a particular case with advanced criterion to test the non-degeneracy of critical points in the flow field. 展开更多
关键词 high pressure compressor flow topologies three-dimensional flows boundary layer aspiration tip clearance
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Mechanical effects of light on the ■-type three-level atom in a high-finesse optical cavity
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作者 刘利伟 谭磊 黄刚 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期377-384,共8页
A theoretical study is carried out for the modification and implication of the effect on the type three level atom in a high-finesse optical cavity driven by light field including spontaneous emission and the cavity d... A theoretical study is carried out for the modification and implication of the effect on the type three level atom in a high-finesse optical cavity driven by light field including spontaneous emission and the cavity decay. Analytic expressions for the dipole force, the friction force, the optical potentials and the friction coefficient are obtained. Then the numerical and graphical methods are used to investigate the friction coefficient with the controlling parameters. It is shown that the friction coefficient is strongly dependent on the controlling parameters. The cooling rate can increase by one order of magnitude more than that of a two-level atomic system. The reason can be given using the dressed states and the Sisyphus cooling mechanism, which would stimulate further experimental investigations. 展开更多
关键词 three-level atom mechanical effects high finesse optical cavity
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Sequential transcatheter arterial chemoembolization,three-dimensional conformal radiotherapy,and high-intensity focused ultrasound treatment for unresectable hepatocellular carcinoma patients 被引量:9
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作者 Shengfa Ni Lingxiang Liu Yongqian Shu 《The Journal of Biomedical Research》 CAS 2012年第4期260-267,共8页
The purpose of this study was to evaluate the outcome of patients with unresectable hepatocellular carcinoma(HCC) treated by sequential therapy of transcatheter arterial chemoembolization(TACE),three-dimensional c... The purpose of this study was to evaluate the outcome of patients with unresectable hepatocellular carcinoma(HCC) treated by sequential therapy of transcatheter arterial chemoembolization(TACE),three-dimensional conformal radiotherapy(3-DCRT) and high-intensity focused ultrasound(HIFU).From October,2005 to September,2010,120 patients with unresectable HCC received the sequential treatments of several courses of TACE followed in 2-4 weeks by 3-DCRT and then a single session of HIFU with a curative intent.The median tumor irradiation dose was 40 Gy.Tumor response,toxicity and overall survival rate were analyzed.Clinicopathologic factors affecting the primary technique effectiveness and overall survival rates were investigated by univariate analysis or multivariate analysis.All 120 HCC patients were followed up by the last follow-up time.Among these patients,hepatic toxicities due to treatment were notable in 9 cases.Gastrointestinal bleeding after the overall treatment occurred in 2 cases,leukopenia of grade III was detected in 1 case,radiation-induced liver disease(RILD) was observed in 2 patients,and first-and second-degree skin burn around the HIFU treatment zone were observed in 2 patients and 1 patient,respectively.Among 120 patients,23,83 and 14 cases achieved partial response,stable disease and progressive disease,respectively.The overall survival rates at 1 year,3 years and 5 years were 70%,35% and 15%,respectively,with a median survival time of 26 months.Both Child-Pugh liver function grading and radiation dose were determined to be independent predictors for overall survival revealed by the multivariate analysis.It is concluded that the sequential therapy of TACE,3-DCRT and HIFU is a promising therapeutic regimen for unresectable HCC. 展开更多
关键词 transcatheter arterial chemoembolization(TACE) three-dimensional con-formal radiotherapy(3DCRT) high-intensity focused ultrasound(HIFU) hepatocellular carcinoma
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Three dimensional dendritic morphology and orientation transition induced by high static magnetic field in directionally solidified Al-10wt.%Zn alloy 被引量:2
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作者 Sansan Shuai Xin Lin +4 位作者 Yuanhao Dong Long Hou Hanlin Liao Jiang Wang Zhongming Ren 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2019年第8期1587-1592,共6页
Effect of high static magnetic field on the dendritic morphology and growth direction in directionally solidified Al-10 wt.%Zn alloy were studied by three-dimensional(3D) X-ray micro-computed tomography, Electron Back... Effect of high static magnetic field on the dendritic morphology and growth direction in directionally solidified Al-10 wt.%Zn alloy were studied by three-dimensional(3D) X-ray micro-computed tomography, Electron Back-scattered Diffraction(EBSD) and X-ray Diffraction(XRD). The application of high static axial magnetic field(5T) during directional solidification was found to destabilize the solid/liquid interface and cause the growth direction of dendrite deviate from thermal gradient, leading to irregular solid/liquid interfacial shape and cellular to dendritic morphology transition. The thermoelectric magnetic convection(TEMC) caused by the interaction of thermoelectric effect and magnetic field was supposed to be responsible for the transition. In addition, the EBSD and XRD results confirm that the preferred growth direction of α-Al was found to transform from the traditionally expected <100> to<110>. The dendrite orientation transition(DOT) in Al-10 wt.%Zn alloy can be attributed to the effect of applied magnetic field on the anisotropy of crystal during solidification. The result indicates the potential application of high static magnetic field in altering the morphology and preferred growth direction of dendrite during directional solidification. 展开更多
关键词 AL-ZN ALLOY high static magnetic field three-dimensional DENDRITE morphology DENDRITE ORIENTATION TRANSITION X-ray computed tomography
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Three-Dimensional Analysis of Melanosomes Isolated from B16 Melanoma Cells by Using Ultra High Voltage Electron Microscopy 被引量:1
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作者 Shuuichi Akazaki Toshie Takahashi +7 位作者 Yujiro Nakano Tomoki Nishida Hirotarou Mori Akio Takaoka Hitomi Aoki Huayua Chen Takahiro Kunisada Kenzo Koike 《Microscopy Research》 2014年第1期1-8,共8页
Melanosomes, isolated by centrifugal separation from culture broth of B16 melanoma cells derived from mouse, were observed by scanning electron microscopy (SEM), and by transmission electron microscopy (TEM). Some int... Melanosomes, isolated by centrifugal separation from culture broth of B16 melanoma cells derived from mouse, were observed by scanning electron microscopy (SEM), and by transmission electron microscopy (TEM). Some interesting structural features were found inside and outside of the melanosomes. By SEM observation, the melanosomes were ellipsoid shape, their surface was not smooth and was covered with rough substructure, 10 to 20 nm particles. By TEM, uneven structure and micro particles were observed in the melanosomes. Furthermore, three-dimensional analysis was tried by using the ultra-high voltage electron microscopy(UHVEM). Micrographs of the melanosomes were taken at various tilted angles by UHVEM, after preparing 500 nm thickness specimens stained with lead citrate. From the micrographs collected, the three-dimensional structures were reconstructed by using i-mode software. Melanin stained by lead and non stained parts was clearly observed in the reconstructed structure. Non stained parts were round, regular size, and distributed widely in the melanosomes. 展开更多
关键词 B16 MELANOMA MELANOSOME Scanning ELECTRON MICROSCOPY Transmission ELECTRON MICROSCOPY Ultra high Voltage ELECTRON MICROSCOPY three-Dimensional Structure
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一例“三高”合并脂肪性肝病患者的全科诊疗案例分析
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作者 李杰 杨昕晖 +2 位作者 曹黎 张晶 姜岳 《中国全科医学》 北大核心 2026年第6期810-816,共7页
背景高血压、糖尿病、血脂异常(“三高”)常与代谢相关脂肪性肝病(FLD)共存,相互影响并显著增加了心血管及肝脏不良结局风险。目前基层全科医生对这类共病患者的规范化诊疗路径尚在探索。目的通过典型病例报告,探索基层全科医生对“三... 背景高血压、糖尿病、血脂异常(“三高”)常与代谢相关脂肪性肝病(FLD)共存,相互影响并显著增加了心血管及肝脏不良结局风险。目前基层全科医生对这类共病患者的规范化诊疗路径尚在探索。目的通过典型病例报告,探索基层全科医生对“三高”合并FLD患者的全科诊疗思路与实践流程。方法报道1例“三高”合并FLD患者的筛查、识别、风险评估、双向转诊及综合管理的全科诊疗过程,展示个体化综合管理方案和全科诊疗路径。结果经过8个月以全科医生为主的全程、全方位综合管理,患者血压、血糖达标,低密度脂蛋白胆固醇降低,体质量减轻,腰围缩小,肝脏脂肪变及纤维化程度显著改善,用药依从性及自我管理能力明显提高。结论通过对“三高”合并FLD患者进行以全科医生为主的综合管理,能够显著改善患者代谢指标及肝脏状况,体现了全科医疗在慢性病共病管理中的核心作用,为优化此类患者的基层规范化管理路径提供了实践参考。 展开更多
关键词 三高 脂肪肝 高血压 糖尿病 血脂异常 全科医学 案例分析
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Magnetic levitation performance of high-temperature superconductor over three magnetic hills of permanent magnet guideway with iron shims of different thicknesses
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作者 Yuming Gong Gang Liang +3 位作者 Lifeng Zhao Yong Zhang Yong Zhao Xuyong Chen 《Journal of Modern Transportation》 2014年第3期187-193,共7页
Superconducting magnetic levitation performance, including levitation force and guidance force, is important for the application of high-temperature super- conducting maglev. Both of them are not only affected by diff... Superconducting magnetic levitation performance, including levitation force and guidance force, is important for the application of high-temperature super- conducting maglev. Both of them are not only affected by different arrays of superconductors and magnets, but also by the thickness of the iron shim between permanent magnets. In order to obtain the best levitation performance, the magnetic field distribution, levitation force, and guidance force of a new type of three magnetic hills of permanent magnet guideway with iron shim of different thicknesses (4, 6, and 8 mm) are discussed in this paper. Simulation analysis and experiment results show that the guideway with iron shim of 8 mm thickness possesses the strongest magnetic field and levitation performance when the suspension gap is larger than 10 mm. However, with the decreasing of suspension gap, the guideway with iron shim of 4 mm thickness possesses the best levitation performance. The phenomena can be attributed to the density distribution of flux and magnetization of iron shim. 展开更多
关键词 high-temperature superconductor three magnetic hills of permanent magnet guideway Thickness of iron shim Levitation force Guidance force
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三波段大口径宽角度红外反射镜的研制
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作者 张静 王鹤 +6 位作者 付秀华 潘永刚 林兆文 魏乃光 李冬旭 刘泽钰 杨飞 《中国光学(中英文)》 北大核心 2026年第1期133-142,共10页
多波段红外探测器可同步获取多波段辐射信息,在目标识别、分类、测温及信息提取等方面显著优于单波段红外探测器,因而成为红外探测器核心研究方向之一。三波段大口径宽角度红外反射镜作为多波段红外探测器的关键光学元件,其性能优劣直... 多波段红外探测器可同步获取多波段辐射信息,在目标识别、分类、测温及信息提取等方面显著优于单波段红外探测器,因而成为红外探测器核心研究方向之一。三波段大口径宽角度红外反射镜作为多波段红外探测器的关键光学元件,其性能优劣直接决定探测精度。在设计阶段,本文选用Ge、ZnS和YbF3三种材料,基于高反射膜的设计理论,通过光谱叠加法结合TFCalc软件优化获得结构合理的红外反射镜膜系。在制备阶段,采用离子源辅助沉积,通过优化沉积工艺解决了膜层脱落的问题。在光谱测试阶段,通过膜厚误差实验和YbF3工艺实验解决了样品光谱漂移的现象。测试结果表明,该红外反射镜在45°入射时,3~5μm波段平均反射率为96.93%;8~12μm波段平均反射率为96.54%;1.064μm反射率为94.64%;在270 mm×270 mm口径内3~5μm、8~12μm波段的光谱非均匀性为4.83%。参照国标GJB 2485A-2019作为环境测试标准,所制备样品成功通过附着力测试和高低温测试,满足多波段红外探测器的使用要求。 展开更多
关键词 大口径红外反射镜 全介质膜系设计 三波段高反射 离子辅助沉积工艺
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A NEW HIGH-ORDER ACCURACY EXPLICIT DIFFERENCE SCHEME FOR SOLVING THREE-DIMENSIONAL PARABOLIC EQUATIONS
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作者 马明书 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第5期497-501,共5页
In this paper, a new three-level explicit difference scheme with high-order accuracy is proposed for solving three-dimensional parabolic equations. The stability condition is r = Delta t/Delta x(2) = Delta t/Delta gam... In this paper, a new three-level explicit difference scheme with high-order accuracy is proposed for solving three-dimensional parabolic equations. The stability condition is r = Delta t/Delta x(2) = Delta t/Delta gamma(2) = Delta t/Delta z(2) less than or equal to 1/4, and the truncation error is O(Delta t(2) + Delta x(4)). 展开更多
关键词 high-order accuracy explicit difference scheme three-dimensional parabolic equation
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1961—2022年三峡地区复合高温干旱事件气候变化特征
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作者 王荣 赵珊珊 陈鲜艳 《地球物理学报》 北大核心 2026年第1期46-54,共9页
利用1961—2022年三峡地区32个国家级气象站逐日平均气温、最高气温、相对湿度和降水资料,采用气象干旱综合指数及阈值法识别复合高温干旱事件,并基于此研究了三峡地区复合高温干旱事件的气候变化特征.结果表明:三峡地区复合高温干旱事... 利用1961—2022年三峡地区32个国家级气象站逐日平均气温、最高气温、相对湿度和降水资料,采用气象干旱综合指数及阈值法识别复合高温干旱事件,并基于此研究了三峡地区复合高温干旱事件的气候变化特征.结果表明:三峡地区复合高温干旱事件主要发生在6月中旬至9月上旬,峰值出现在8月上中旬;平均每年有约60%站点出现复合高温干旱事件,其中三峡地区北部和西部是复合高温干旱事件的高发区;有68%的单站复合高温干旱事件持续时间在4d以下.近62 a,三峡大部地区年复合高温干旱日数呈增多趋势;年最大单日复合高温干旱范围呈增大趋势;有78%的站点复合高温干旱强度呈增强趋势;三峡地区区域性复合高温干旱过程年发生概率为48%,区域性复合高温干旱过程的次数、持续日数、影响范围、高温强度、干旱强度、综合强度均呈增加趋势,尤其是21世纪以来,区域性复合高温干旱事件的极端性明显增强.全球气候增暖背景下,三峡地区复合高温干旱事件趋于严重,需高度重视其对水利工程运营的不利影响. 展开更多
关键词 三峡地区 复合高温干旱 气候变化
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2014-2023年某综合医院中老年住院患者“三高”患病情况调查研究
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作者 付瑶 黄勤 《中国社会医学杂志》 2026年第1期77-80,共4页
目的 分析四川某综合医院近10年中老年住院患者“三高”患病情况及影响因素,以及该人群慢性病共病情况,为当地及类似地区制定中老年“三高”防控与管理策略提供参考。方法 提取2014-2023年某综合医院45~<65岁住院患者病案首页数据,... 目的 分析四川某综合医院近10年中老年住院患者“三高”患病情况及影响因素,以及该人群慢性病共病情况,为当地及类似地区制定中老年“三高”防控与管理策略提供参考。方法 提取2014-2023年某综合医院45~<65岁住院患者病案首页数据,包括患者基本信息、出院诊断信息等。采用多元线性回归模型分析“三高”患病数目的影响因素,调用NetDraw软件绘制“三高”患者慢性病共病网络图。结果 2014-2023年间收治的33 662例中老年住院患者中,39.98%(13 458/33 662)至少患有1种“三高”疾病,14.35%(4 830/33 662)至少患有2种“三高”疾病,3.06%(1 029/33 662)同时患有3种“三高”疾病。多元线性回归分析显示,性别、年龄、婚姻状况、职业均影响“三高”疾病的发生(P<0.05)。高频病种共现网络分析显示,“三高”患者前5位核心病种为高血压、糖尿病、高脂血症、慢性胃炎、脂肪肝。结论 应采取多维度、综合性的策略,对65岁以下存在“三高”危险因素的人群进行早期干预,降低“三高”疾病的患病风险,实现疾病预防、诊断、治疗与康复的一体化全周期管理。 展开更多
关键词 三高 高血压 糖尿病 高脂血症 中老年 慢性病 共病
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公立医院党支部党建业务融合的三维路径探析
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作者 陈海振 张敏州 +1 位作者 张晓璇 郭力恒 《现代医院》 2026年第2期201-203,207,共4页
推进党建与业务深度融合是加强党对公立医院全面领导、实现高质量发展的必然要求。本文针对当前公立医院党建与业务融合中存在“两张皮”的现实困境,以广东省中医院大德路总院临床第二党总支内科第五党支部为典型案例,系统剖析其融合过... 推进党建与业务深度融合是加强党对公立医院全面领导、实现高质量发展的必然要求。本文针对当前公立医院党建与业务融合中存在“两张皮”的现实困境,以广东省中医院大德路总院临床第二党总支内科第五党支部为典型案例,系统剖析其融合过程中的结构性、机制性及文化性阻滞因素,构建以目标层、机制层、实践层为核心的三维融合模式,并通过特色品牌化实践实现多路径协同推进。实践表明,该模式显著增强了党支部的组织效能、服务能力与创新活力,为公立医院基层党建与业务深度融合提供了系统化、可复制的实践范式,对公立医院具有一定的参考与推广价值。 展开更多
关键词 公立医院 党支部建设 党建业务融合 三维融合模式 高质量发展
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基于三维元胞自动机的高层火灾蔓延过程快速模拟方法
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作者 王祺 林旭川 +2 位作者 钟江荣 宋春 崔易腾 《自然灾害学报》 北大核心 2026年第1期1-10,共10页
为解决高层建筑火灾蔓延模拟难度大、耗时长等问题,该文提出基于三维元胞自动机的高层建筑火灾蔓延快速模拟方法。将三维空间离散为元胞,建立状态转换规则,结合材料属性与火灾动力学特性,引入基于PyroSim实验的概率机制,量化风速对火灾... 为解决高层建筑火灾蔓延模拟难度大、耗时长等问题,该文提出基于三维元胞自动机的高层建筑火灾蔓延快速模拟方法。将三维空间离散为元胞,建立状态转换规则,结合材料属性与火灾动力学特性,引入基于PyroSim实验的概率机制,量化风速对火灾蔓延的影响,实现火灾动态模拟。以2011年沈阳皇朝万鑫大厦火灾为案例,利用模型模拟过火面积与实际灾情(9814 m^(2)),误差在7%以内,在普通计算机配置上单次模拟耗时仅40.51 s,验证了模型合理性以及计算方法的高效性。进一步参数分析表明,外保温体系可燃性高时,火势沿空腔快速蔓延,燃烧持续6.5 h;采用非燃性体系后,火势受限至36 m^(2),1.5 h内稳定。该方法可有效表征高层火灾蔓延的空间异质性,可为高层建筑防火设计优化及城市火灾防控提供高效工具。 展开更多
关键词 三维元胞自动机 高层建筑火灾蔓延 风速概率耦合 案例研究 外保温材料
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