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Low noise,continuous-wave single-frequency 1.5-μm laser generated by a singly resonant optical parametric oscillator 被引量:3
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作者 刘建丽 刘勤 +2 位作者 李宏 李鹏 张宽收 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第11期312-316,共5页
We report a low noise continuous-wave (CW) single-frequency 1.5-μm laser source obtained by a singly resonant optical parametric oscillator (SRO) based on periodically poled lithium niobate (PPLN). The SRO was ... We report a low noise continuous-wave (CW) single-frequency 1.5-μm laser source obtained by a singly resonant optical parametric oscillator (SRO) based on periodically poled lithium niobate (PPLN). The SRO was pumped by a CW single-frequency Nd:YVO4 laser at 1.06μm. The 1.02 W of CW single-frequency signal laser at 1.5 μm was obtained at pump power of 6 W. At the output power of around 0.75 W, the power stability was better than ±l.5% and no mode-hopping was observed in 30 min and frequency stability was better than 8.5 MHz in 1 min. The signal wavelength could be tuned from 1.57 to 1.59 μm by varying the PPLN temperature. The 1.5-μm laser exhibits low noise characteristics, the intensity noise of the laser reaches the shot noise limit (SNL) at an analysis frequency of 4 MHz and the phase noise is less than 1 dB above the SNL at analysis frequencies above 10 MHz. 展开更多
关键词 singly resonant optical parametric oscillator 1.5-μm laser single-frequency operation low noise
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Paramagnetic Anisotropy of CdGd_2(WO_4)_(4-δ) Single Crystal 被引量:1
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作者 侯碧辉 王雅丽 +2 位作者 孙桂芳 刘国庆 王吉有 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第1期27-30,共4页
CdGd2 (WO4)4 -δ single crystal was grown using the Czochralski's method. The crystal structure was tetragonal seheelite with lattice parameters a = b = 0.5203 nm and c = 1. 1359 nm. There were vacancies of (WO4)... CdGd2 (WO4)4 -δ single crystal was grown using the Czochralski's method. The crystal structure was tetragonal seheelite with lattice parameters a = b = 0.5203 nm and c = 1. 1359 nm. There were vacancies of (WO4)^2- , therefore, there were some Gd^2+ ions. Langevin paramagnetism and anisotropy were observed from the δ-T curves at room temperature. The susceptibility X//was 3.5018×10^-3, and X⊥ was 3.4403× 10^-2. The anisotropy was also observed in the electron spin resonance (ESR) experiments. The anisotropic Land6 factors were g//= 2. 1333 and g~ = 2. 8411. The direction of easy magnetization was in the α-b plane. Anisotropic paramagnetic Curie constants C//and C⊥ were not only related to macroscopic a that was observed through the experiment, but were also related to J⊥ and J//, which were the microscopic quantum numbers of the Gd^2+ and Gd^3| ions. Based on the detailed analyses, the proportion of 36.8% of Gd^3+ ions to 63.2% of Gd^2+ ions in the Gd ions of the CdGd2(WO4)4-δ crystal was calculated, and δ was 0.638 in the single crystal. 展开更多
关键词 CdGd(WO4)4-δ single crystal ANISOTROPY Langevin paramagnetism rare earths
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Synthesis and Structure of Large Single Crystal of TPAF-AlPO_4-5 Molecular Sieve
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作者 Qiu Shilun, Pang Wenqin and Xu Ruren (Institute of Synthetic and Catalytic Chemistry, Jilin University, Changchun) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1989年第2期120-124,共5页
A large single crystal of TPAF-AlPO4-5 molecular sieve was synthesized by hydrothermal crystallization in the presence of ammonium fluoride. Starting material composition was · 1 P2O5 · 1 Al2O3 · 2. 2 T... A large single crystal of TPAF-AlPO4-5 molecular sieve was synthesized by hydrothermal crystallization in the presence of ammonium fluoride. Starting material composition was · 1 P2O5 · 1 Al2O3 · 2. 2 TPAOH · 1. 7 NH4F ·318 H2O. The crystal size has a hexagonal prism with 80μm across and 500μm length.The structure of tetrapropylarnmonium fluoride - aluminium phosphate type-5 was investigated with X-ray diffraction. The unit cell composition is 12AlPO4 · TPAF, space group P6cc (a= 13. 740(5), c= 8. 474(4) A ). Average bond distances are: P-O 1. 564A and Al-O 1. 640A ,which may be due to the partial disorder of the arrangement of P, Al in the framework. The angles of O-T-O and T-O-T (T?P, Al) are 102-116° and 148-176°, respectively. Residue electron density was not well enough defined to give a precise position for tetrapropylammonium fluoride (TPAF). The template agent, TPA+ cations, situate in the 12-ring channels and F- anions locate in double 4-rings near the 12-ring channels. Fixing atomic positions for the TPAF reduced the unweighted and weighted R, R, from 0. 063 and 0. 082 to 0. 046 and 0. 042,respectively. 展开更多
关键词 AlPO_4-5 molecular sieve single crystal
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A new integration algorithm for finite deformation of thermo-elasto-viscoplastic single crystals
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作者 Dan Zhao Yi-Guo Zhu +1 位作者 Ping Hu Wan-Xi Zhang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第5期709-717,共9页
An algorithm for integrating the constitutive equations in thermal framework is presented, in which the plastic deformation gradient is chosen as the integration variable. Compared with the classic algorithm, a key fe... An algorithm for integrating the constitutive equations in thermal framework is presented, in which the plastic deformation gradient is chosen as the integration variable. Compared with the classic algorithm, a key feature of this new approach is that it can describe the finite deformation of crystals under thermal conditions. The obtained plastic deformation gradient contains not only plastic defor- mation but also thermal effects. The governing equation for the plastic deformation gradient is obtained based on ther- mal multiplicative decomposition of the total deformation gradient. An implicit method is used to integrate this evo- lution equation to ensure stability. Single crystal 1 100 aluminum is investigated to demonstrate practical applications of the model. The effects of anisotropic properties, time step, strain rate and temperature are calculated using this integration model. 展开更多
关键词 Integration algorithm - Thermal effect Anisotropic elasticity single crystal Finite deformation
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Static and Dynamic Analysis of Lasing Action from Single and Coupled Photonic Crystal Nanocavity Lasers
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作者 Peng-Chao Zhao Fan Qi +2 位作者 Ai-Yi Qi Yu-Fei Wang Wan-Hua Zheng 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第2期30-33,共4页
The single and coupled photonic crystal nanocavity lasers are fabricated in the InGaAsP material system and their static and dynamic features are compared. The coupled-cavity lasers show a larger lasing e^ciency and g... The single and coupled photonic crystal nanocavity lasers are fabricated in the InGaAsP material system and their static and dynamic features are compared. The coupled-cavity lasers show a larger lasing e^ciency and generate an output power higher than the single-cavity lasers, results that are consistent with the theoretical results obtained by rate equations. In dynamic regime, the single-cavity lasers produce pulses as short as 113 ps, while the coupled-cavity lasers show a significantly longer lasing duration. These results indicate that the photonic crystal laser is a promising candidate for the light source in high-speed photonic integrated circuit. 展开更多
关键词 Static and Dynamic Analysis of Lasing action from single and Coupled Photonic Crystal Nanocavity Lasers
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The effects of Er^(3+) ion concentration on 2.0-μm emission performance in Ho^(3+)/Tm^(3+) co-doped Na_(5)Y_(9)F_(32) single crystal under 800-nm excitation
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作者 Benli Ding Xiong Zhou +3 位作者 Jianli Zhang Haiping Xia Hongwei Song Baojiu Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第1期511-518,共8页
Na_(5)Y_(9)F_(32) single crystals doped with ~0.8-mol% Ho^(3+),~1-mol% Tm^(3+),and various Er^(3+) ion concentrations were prepared by a modified Bridgman method.The effects of Er^(3+)ion concentration on 2.0-μm emis... Na_(5)Y_(9)F_(32) single crystals doped with ~0.8-mol% Ho^(3+),~1-mol% Tm^(3+),and various Er^(3+) ion concentrations were prepared by a modified Bridgman method.The effects of Er^(3+)ion concentration on 2.0-μm emission excited by an800-nm laser diode were investigated with the help of their spectroscopic properties.The intensity of 2.0-μm emission reached to maximum when the Er^(3+) ion concentration was ~1 mol%.The energy transfer mechanisms between Er^(3+),Ho^(3+),and Tm^(3+) ions were identified from the change of the absorption spectra,the emission spectra,and the measured decay curves.The maximum 2.0-μm emission cross section of the Er^(3+)/Ho^(3+)/Tm^(3+)tri-doped Na_(5)Y_(9)F_(32) single crystal reached 5.26 × 10^(-21) cm^(2).The gain cross section spectra were calculated according to the absorption and emission cross section spectra.The cross section for ~2.0-μm emission became a positive gain once the inversion level of population was reached 30%.The energy transfer efficiency was further increased by 11.81% through the incorporation of Er^(3+) ion into Ho^(3+)/Tm^(3+) system estimated from the measured lifetimes of Ho^(3+)/Tm^(3+)-and Er^(3+)/Ho^(3+)/Tm^(3+)-doped Na_(5)Y_(9)F_(32)single crystals.The present results illustrated that the Er^(3+)/Ho^(3+)/Tm^(3+)tri-doped Na_(5)Y_(9)F_(32) single crystals can be used as promising candidate for 2.0-μm laser. 展开更多
关键词 2.0-μm emission Er^(3+)/Ho^(3+)/Tm^(3+) energy transfer Na_(5)Y_(9)F_(32)single crystal
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STUDY ON ANTIBACTERIAL ACTION OF 4-[P-ACETYLAMINO]BENZENESULFONAMIDOL SELENOMORPHOLINE BY MICROCALORIMETRY 被引量:2
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作者 李曦 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2000年第1期28-33,共6页
Antibacterial action of 4-[p-acetylamino benzenesulfonamido] selenomorpholine (SeB) was studied by microcalorimetry with an LKB-2277 Bioactivity Moni-tor. It was found that SeB had the capacity to inhibit the metaboli... Antibacterial action of 4-[p-acetylamino benzenesulfonamido] selenomorpholine (SeB) was studied by microcalorimetry with an LKB-2277 Bioactivity Moni-tor. It was found that SeB had the capacity to inhibit the metabolic growth of Escherichia coli. But in different sol-vent, the extent of inhibition is different. Removing the effect of solvent, we obtained the half-inhibition conce.ntra-tion(IC50) of SeB from the power-time curves. The value of IC50 of SeB was 1319μg ·mL-1. 展开更多
关键词 antibacterial action 4-[p-acetylamino benzenesulfonamido] selenomorpholine MICROCALORIMETRY
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Study of Single Plated Principle on Large Diameter Circular Weft Knitting Machine 被引量:2
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作者 孙锋 《Journal of China Textile University(English Edition)》 EI CAS 2000年第2期88-91,共4页
A new theory and method that differs from the tradition-al single plated weft - knitting theory and method hasbeen expounded after theoretical analyzing and experi-mental proving. If the new method is used when platin... A new theory and method that differs from the tradition-al single plated weft - knitting theory and method hasbeen expounded after theoretical analyzing and experi-mental proving. If the new method is used when platingstitch is knitted on large diameter weft knitting machine,the thorny problem of long standing that ground yarn iseasy to appear on the face side of fabric is solved. Thenew method, i.e, the production of physical ability oftraining uniform for serviceman has been used. 展开更多
关键词 large diameter single plated WEFT - knit vertical LAPPING ANGLE horizontal LAPPING ANGLE FEEDING tension
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CHINA: MAIN GEODETIC ACTIONS 1996-2000
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作者 Chen Junyong(National Bureau of Surveying and Mapping, Beijing) CAS Member 《Bulletin of the Chinese Academy of Sciences》 1996年第4期286-290,共5页
This article reviews the progress made in geodetic work in China since the 1980s.In order to meet the needs of China’s economic and defense construction,and scientific and social development in the early 21th century... This article reviews the progress made in geodetic work in China since the 1980s.In order to meet the needs of China’s economic and defense construction,and scientific and social development in the early 21th century,some main geodetic actions which should be completed before 2000 are proposed as follows.(1) Monitoring vertical crustal movements and conducting studies on its mechanism.Releveling of the second phase of the national first order leveling network.Computation of the vertical crustal movement.(2) Improvement of national space geodetic network.The main task is to lay down a national B-order GPS network and complete its data processing.(3) Refining of Chinese local gravity field on land and sea.The determination of Chinese local quasi geoid with higher than one meter accuracy.Application of 展开更多
关键词 GPS DATA VLBI MAIN GEODETIC actionS 1996-2000 CHINA
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中药治疗糖尿病作用机制研究进展
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作者 李红艳 戴思思 +4 位作者 吴威 周佳欣 陈智慧 杨关林 张会永 《世界科学技术-中医药现代化》 CSCD 北大核心 2024年第6期1410-1433,共24页
糖尿病(Diabetes mellitus,DM)是以长期高血糖为主要特征的内分泌代谢性疾病,严重威胁着人类的健康与生活质量,随着我国生活质量的提高以及不健康的生活方式,DM发病率持续升高并趋于年轻化,深入开展降血糖治疗的研究刻不容缓。DM以胰岛... 糖尿病(Diabetes mellitus,DM)是以长期高血糖为主要特征的内分泌代谢性疾病,严重威胁着人类的健康与生活质量,随着我国生活质量的提高以及不健康的生活方式,DM发病率持续升高并趋于年轻化,深入开展降血糖治疗的研究刻不容缓。DM以胰岛素的绝对或相对不足为病理基础,目前尚无根治手段,西医多采用注射胰岛素或口服降糖药物对症治疗,虽然效果显著,但长期使用易产生毒副作用。中药治疗DM具有多途径、多靶点的优势,通过促进胰岛素分泌、改善胰岛素抵抗、调节糖脂代谢、抗氧化应激等发挥降血糖作用,其疗效显著且毒副反应少。近年来,有关中药及复方对DM动物模型的作用机制研究较多,笔者通过回顾近年来相关文献,对单味中药、中药复方、中药有效成分降血糖作用机制及其相关实验设计等进行系统梳理,从促进胰岛素分泌、抑制糖异生、促进糖原合成、改善胰岛素抵抗、抑制糖苷酶活性、缓解氧化应激损伤、抑制炎症反应和调节肠道菌群等方面对中药降血糖的作用机制研究及实验设计进行归纳总结,以期为中药降血糖更广泛的临床应用及其深入的药效学机制研究提供参考。 展开更多
关键词 单味药 中药复方 糖尿病 降血糖 作用机制
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基于联合有限元-离散元的混凝土重力坝破坏三维仿真模拟 被引量:6
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作者 申振东 许栋 +2 位作者 白玉川 及春宁 Ante Munjiza 《计算力学学报》 CAS CSCD 北大核心 2017年第1期49-56,共8页
水利工程中混凝土重力坝在地震等作用下的三维破坏形式以及破坏过程对大坝安全影响重大。本文建立了固体材料的联合有限元-离散元(Combined Finite-Discrete Element)三维数学模型,并引入Single/Smeared断裂损伤模型,模拟混凝土材料的... 水利工程中混凝土重力坝在地震等作用下的三维破坏形式以及破坏过程对大坝安全影响重大。本文建立了固体材料的联合有限元-离散元(Combined Finite-Discrete Element)三维数学模型,并引入Single/Smeared断裂损伤模型,模拟混凝土材料的破坏。数学模型经验证后,用于地震作用下混凝土重力坝破坏的三维数值模拟,结果表明,联合有限元-离散元方法能够有效模拟坝体的破坏模式和破坏阈值条件,且具有将坝体连续变形与不连续断裂有机结合的优点。通过一系列数值模拟工况的对比,分析了模型网格分辨率对破坏条件、破坏模式以及程序计算效率的影响,研究结果能够为大坝的抗震设计提供有价值的参考。 展开更多
关键词 混凝土重力坝 联合有限元-离散元 single/Smeared破坏模型 三维模拟
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单电机线驱动多指柔性外骨骼机械手设计 被引量:1
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作者 高孟扬 王钰 +1 位作者 刘环宇 陈明祥 《青岛大学学报(自然科学版)》 CAS 2024年第1期79-84,共6页
为使外骨骼机械手的作用更加柔顺、灵活、轻量和低成本,设计了一款基于柔索传递驱动的外骨骼手,整手有10条驱动线,只采用了1台伺服电机做动力源(单驱),通过传动结构和电磁线圈的通断产生的止停作用,使单一动力源的运动输出能合理分配给... 为使外骨骼机械手的作用更加柔顺、灵活、轻量和低成本,设计了一款基于柔索传递驱动的外骨骼手,整手有10条驱动线,只采用了1台伺服电机做动力源(单驱),通过传动结构和电磁线圈的通断产生的止停作用,使单一动力源的运动输出能合理分配给5根手指的驱动线,并实时控制每根手指上的两条驱动线,生成符合要求的行程运动,缩减了外骨骼手动力装置的体积和重量,降低了生产成本。 展开更多
关键词 外骨骼手 线驱动 单驱多指 单指多驱 电磁铁止动
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总体国家安全观下电子档案单套制风险治理研究--基于“理念-主体-行动”的三维分析框架 被引量:5
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作者 朱兰兰 段燕鸽 《档案管理》 北大核心 2022年第6期31-37,共7页
单套制是数字时代电子档案管理的必然趋势。总体国家安全观作为新时代党中央对国家安全理论的重要创新,能够推进电子档案单套制进程。基于此,识别电子档案单套制风险问题,并在此基础上提出电子档案单套制风险治理的“理念—主体—行动... 单套制是数字时代电子档案管理的必然趋势。总体国家安全观作为新时代党中央对国家安全理论的重要创新,能够推进电子档案单套制进程。基于此,识别电子档案单套制风险问题,并在此基础上提出电子档案单套制风险治理的“理念—主体—行动”三维分析框架,使得多元治理主体以总体国家安全观的系统思维、法治思维、战略思维和底线思维为治理理念,开展涵括认知观念、制度体系、管理机制和技术应用的治理行动。 展开更多
关键词 总体国家安全观 电子档案 单套制 风险治理 理念—主体—行动
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排管机械手扶持装置的研制
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作者 邢大伟 王翠 +3 位作者 张欣宇 白丙建 郝熔冰 李景航 《机械工程师》 2024年第3期112-114,共3页
扶持装置在排管机械手中起扶持管柱的作用,是排管装置重要的组成部分之一。文中介绍了单驱动双作用扶持装置的结构组成、工作流程及试验情况。该单驱动双作用扶持装置的成功设计,节约了排管机械手生产制造成本,降低了故障率,提升了排管... 扶持装置在排管机械手中起扶持管柱的作用,是排管装置重要的组成部分之一。文中介绍了单驱动双作用扶持装置的结构组成、工作流程及试验情况。该单驱动双作用扶持装置的成功设计,节约了排管机械手生产制造成本,降低了故障率,提升了排管机械手的性能,对排管机械手的发展具有重要意义。 展开更多
关键词 扶持装置 单驱动双作用 排管机械手
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海上石油平台气动单作用蝶阀试验研究
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作者 周磊 《石化技术》 CAS 2024年第7期30-32,共3页
主要阐述齿轮齿条式单作用蝶阀的结构特点、工作原理,阀体部件的设计和计算,不同数量弹簧作用下的转角及试验方法的结果。通过合理设计阀体部件、选择合适的弹簧数量和材质,可以实现阀门在不同工况下的优良性能。气动单作用蝶阀操作简单... 主要阐述齿轮齿条式单作用蝶阀的结构特点、工作原理,阀体部件的设计和计算,不同数量弹簧作用下的转角及试验方法的结果。通过合理设计阀体部件、选择合适的弹簧数量和材质,可以实现阀门在不同工况下的优良性能。气动单作用蝶阀操作简单,主要由阀体、阀瓣、阀杆、齿轮齿条机构和气动驱动装置等部分组成,在渤海油田应用十分广泛。 展开更多
关键词 蝶阀 电磁阀 单作用阀
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钻孔分层抽水试验装置防缠绕接头设计
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作者 刘蓓 张雄 +2 位作者 何涛 段晓 吕轩 《地质装备》 2024年第5期1-5,共5页
分层抽水试验装置常用于地下水资源与液体矿产资源评价工作,试验装置由孔内和地表设备组成,地表与孔内设备通过各种管线连接。在安装和拆卸试验装置的过程中,由于孔内试验设备之间通过螺纹连接会发生相对转动,这些管线与钻杆(或设备)常... 分层抽水试验装置常用于地下水资源与液体矿产资源评价工作,试验装置由孔内和地表设备组成,地表与孔内设备通过各种管线连接。在安装和拆卸试验装置的过程中,由于孔内试验设备之间通过螺纹连接会发生相对转动,这些管线与钻杆(或设备)常发生缠绕。本文设计了一种防缠绕单双动接头,在单动状态下,接头上下两端的设备安装和拆卸时可实现静止不转动;在双动状态下,接头上下两端的设备可实现同步回转,从而有效防止分层抽水试验装置的管线缠绕损坏,提升抽水试验工作的质量和效率。 展开更多
关键词 封隔器 单双动接头 水文钻孔 分层抽水试验
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新近系地层大直径取心质量影响因素分析及对策研究
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作者 王松珍 杜双杰 +1 位作者 张雷鹏 孙红伟 《钻探工程》 2024年第2期146-153,共8页
在郑州市主城区与东部新城区地热资源勘查评价项目中,勘查目的层为新近系明化镇组和馆陶组,在勘查初期存在取心质量不稳定的问题。通过对影响取心质量的地质因素和工程因素的分析发现,初期采用的川7-4型单动双管取心工具配装的卡箍式岩... 在郑州市主城区与东部新城区地热资源勘查评价项目中,勘查目的层为新近系明化镇组和馆陶组,在勘查初期存在取心质量不稳定的问题。通过对影响取心质量的地质因素和工程因素的分析发现,初期采用的川7-4型单动双管取心工具配装的卡箍式岩心爪,难以适应胶结程度差异大、复杂多变的新近系地层。针对影响取心质量的因素,采用了钙化泥浆,优化了钻进参数,改进了钻头结构,设计加工了卡板式岩心爪与卡箍式岩心爪组合的双作用岩心爪。在后续的勘查施工中,有效提高了岩心采取率,解决了取心质量不稳定的问题。 展开更多
关键词 新近系地层 取心质量 地质因素 工程因素 单动双管取心工具 双作用岩心爪 地热资源勘查
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Case Report:Lance-Adams syndrome:a report of two cases 被引量:6
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作者 ZHANG Yan-xing1,2, LIU Jian-ren1, JIANG biao3, LIU Hui-qin1, DING Mei-ping1, SONG Shui-jiang1, ZHANG Bao-rong1, ZHANG Hong4, XU Bin5, CHEN Huai-hong6, WANG Zhong-jin1, HUANG Jian-zheng1 (1Department of Neurology, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China) (2Department of Neurology, Shaoxing People’s Hospital, Shaoxing 312000, China) (3Department of Radiology, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China) (4Department of Nuclear Medicine, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China) (5Department of Neurology, the Second Affiliated Hospital, Zhejiang University of Traditional Chinese Medicine, Hangzhou 310005, China) (6Department of Geratology, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China) 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第10期715-720,共6页
Chronic post-hypoxic myoclonus, also known as Lance-Adams syndrome (LAS), is a rare complication of successful cardiopulmanry resuscitation often accompanied by action myoclonus and cerebellar ataxia. It is seen in pa... Chronic post-hypoxic myoclonus, also known as Lance-Adams syndrome (LAS), is a rare complication of successful cardiopulmanry resuscitation often accompanied by action myoclonus and cerebellar ataxia. It is seen in patients who have un-dergone a cardiorespiratory arrest, regained consciousness afterwards, and then developed myoclonus days or weeks after the event. Worldwide, 122 cases have been reported in the literature so far, including 1 case of Chinese. Here we report 2 Chinese LAS patients with detailed neuroimagings. Cranial single photon emission computed tomography (SPECT) of patient 1, a 52-year-old woman, showed a mild hypoperfusion in her left temporal lobe, whereas patient 2, a 54-year-old woman, manifested a mild bilateral decrease of glucose metabolism in the frontal lobes and a mild to moderate decrease of the N-acetyl aspartate (NAA) peak in the bilateral hippocampi by cranial [18F]-fluorodeoxyglucose positron emission tomographic (PET) scan and cranial magnetic resonance spectroscopy (MRS), respectively. We also review the literature on the neuroimaging, pathogenesis, and treatment of LAS. 展开更多
关键词 Lance-Adams SYNDROME Chronic post-hypoxic MYOCLONUS action MYOCLONUS CEREBELLAR ATAXIA single photon EMISSION computed TOMOGRAPHY Positron EMISSION TOMOGRAPHY Magnetic resonance spectroscopy
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直九-2稳瞄操作控制系统的设计 被引量:1
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作者 祝斌 刘建业 《工程设计学报》 CSCD 2001年第2期93-95,共3页
稳瞄系统是直升机上重要的光电系统 ,稳瞄操作控制系统是稳瞄系统的一个重要的子系统 ,稳瞄系统中所有的人工操作都是通过稳瞄操作控制系统来完成的 .采用单片机来实现稳瞄操作控制系统的功能 ,介绍了 80 C196单片机系统和 PC10 4嵌入... 稳瞄系统是直升机上重要的光电系统 ,稳瞄操作控制系统是稳瞄系统的一个重要的子系统 ,稳瞄系统中所有的人工操作都是通过稳瞄操作控制系统来完成的 .采用单片机来实现稳瞄操作控制系统的功能 ,介绍了 80 C196单片机系统和 PC10 4嵌入式系统的硬件结构和软件设计 .该系统目前运行状况良好 ,满足了设计要求 . 展开更多
关键词 稳瞄操作控制系统 单片机 硬件结构 软件设计 直九-2 直升飞机 光电系统
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ZY-850L矿用履带式全方位钻机的研制 被引量:1
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作者 张始斋 《煤炭技术》 CAS 北大核心 2015年第7期234-236,共3页
针对煤矿井下钻机在进行大倾角钻进时,机架倾角调节困难,易发生倾覆的现象,提出了全方位履带钻机钻孔施工的工艺方法,研制了ZY-850L矿用履带式全方位钻机。详细介绍了钻机的结构特点及主要参数,详细论述了钻机的总体布局、液压系统及关... 针对煤矿井下钻机在进行大倾角钻进时,机架倾角调节困难,易发生倾覆的现象,提出了全方位履带钻机钻孔施工的工艺方法,研制了ZY-850L矿用履带式全方位钻机。详细介绍了钻机的结构特点及主要参数,详细论述了钻机的总体布局、液压系统及关键部件的强度分析。通过实验室及现场应用证明:该钻机满足实际生产要求,尤其在大倾角施工时,操作安全、方便、快捷,为同类钻机设计提供参考和依据。 展开更多
关键词 钻机 履带车 全方位 单动液压系统
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