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Isothermal hydrogen absorption process of Pd-capped Mg films traced by ion beam techniques and optical methods
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作者 D.Abejón P.Prieto +6 位作者 J.K.Kim A.Redondo-Cubero M.L.Crespillo F.Leardini I.J.Ferrer G.García J.R.Ares 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第9期3675-3684,共10页
Pd-capped nanocrystalline Mg films were prepared by electron beam evaporation and hydrogenated under isothermal conditions to inves-tigate the hydrogen absorption process via ion beam techniques and in situ optical me... Pd-capped nanocrystalline Mg films were prepared by electron beam evaporation and hydrogenated under isothermal conditions to inves-tigate the hydrogen absorption process via ion beam techniques and in situ optical methods.Films were characterized by different techniques such as X-ray diffraction(XRD)and scanning electron microscopy(SEM).Rutherford backscattering spectrometry(RBS)and elastic recoil detection analysis(ERDA)provided a detailed compositional depth profile of the films during hydrogenation.Gas-solid reaction kinetics theory applied to ERDA data revealed a H absorption mechanism controlled by H diffusion.This rate-limiting step was also confirmed by XRD measurements.The diffusion coefficient(D)was also determined via RBS and ERDA,with a value of(1.1±0.1)·10^(−13)cm^(2)/s at 140℃.Results confirm the validity of IBA to monitor the hydrogenation process and to extract the control mechanism of the process.The H kinetic information given by optical methods is strongly influenced by the optical absorption of the magnesium layer,revealing that thinner films are needed to extract further and reliable information from that technique. 展开更多
关键词 Magnesium hydride Hydrogen absorption Ion beam techniques Optical tracing Absorption mechanism
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An advanced segmentation using area and boundary tracing technique in extraction of lungs region
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作者 Kiran THAPALIYA Sang-Woong LEE +2 位作者 Jae-Young PYU Heon JEONG Goo-Rak KWON 《Journal of Central South University》 SCIE EI CAS 2014年第10期3811-3820,共10页
A new method is presented for the segmentation of pulmonary parenchyma. The proposed method is based on the area calculation of different objects in the image. The main purpose of the proposed algorithm is the segment... A new method is presented for the segmentation of pulmonary parenchyma. The proposed method is based on the area calculation of different objects in the image. The main purpose of the proposed algorithm is the segment of the lungs images from the computer tomography(CT) images. The original image is binarized using the bit-plane slicing technique and among the different images the best binarized image is chosen. After binarization, the labeling is done and the area of each label is calculated from which the next level of binarized image is obtained. Then, the boundary tracing algorithm is applied to get another level of binarized image. The proposed method is able to extract lung region from the original images. The experimental results show the significance of the proposed method. 展开更多
关键词 bit-plane slicing technique connected component labeling area tracing boundary tracing
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Application of Chemical Tracing Experiment Technique in Leakage Detection of Hydraulic Engineering
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作者 李亚军 《Agricultural Science & Technology》 CAS 2011年第9期1385-1387,共3页
[Objective] The research aimed to study the application of chemical tracing experiment technique in leakage detection of hydraulic engineering.[Method] According to the current situation of Sanyuan Western Suburb Rese... [Objective] The research aimed to study the application of chemical tracing experiment technique in leakage detection of hydraulic engineering.[Method] According to the current situation of Sanyuan Western Suburb Reservoir in Xianyang City of Shaanxi Province,three sections (L1,L2 and L3) were set.KI was selected as the chemical tracer to carry out the tracing and detection research.[Result] There was no obvious leakage phenomenon in L1,L2 and L3 sections.The impermeability of rock in some dam abutments was bad.[Conclusion] The leakage reason of Western Suburb Reservoir was that the impermeability of rock in some dam abutments couldn’t satisfy seepage requirement.After the reservoir was put into operation,the water level in front of dam rose,and the ground water level of dam abutment also rose.The penetration water pressure correspondingly increased,and the water content of bank slope at the downstream of dam increased. 展开更多
关键词 Chemical tracing experiment technique TRACER tracing technique LEAKAGE Hydraulic engineering
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The Double Projecting Neuron of the Cat Spinal Dorsal Horn——A Study with Double Retrograde Fluorescent Tracing Technique
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作者 Jiao Shoushu Liu Yujun +2 位作者 Wang Yuanshen Zhang Guofeng Lu Guowei 《解剖学报》 CAS 1985年第3期243-243,共1页
The new double projecting neurons were found in the cat spinal dorsal horn by the double retrograde fluorescent tracing technique.Fast Blue(FB)was injected into unilateral dorsal column nucleus(DCN)of adult cats anest... The new double projecting neurons were found in the cat spinal dorsal horn by the double retrograde fluorescent tracing technique.Fast Blue(FB)was injected into unilateral dorsal column nucleus(DCN)of adult cats anesthetized with pentobarbital.Nuclear Yellow(NY)was injected ipsilaterally into the lateral cervical nucleus(LCN)8-9 days later.After an additional 18-30 hrs. 展开更多
关键词 A Study with Double Retrograde Fluorescent tracing technique The Double Projecting Neuron of the Cat Spinal Dorsal Horn
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Arc-length technique for nonlinear finite element analysis 被引量:9
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作者 MEMONBashir-Ahmed 苏小卒 《Journal of Zhejiang University Science》 EI CSCD 2004年第5期618-628,共11页
Nonlinear solution of reinforced concrete structures, particularly complete load-deflection response, requires tracing of the equilibrium path and proper treatment of the limit and bifurcation points. In this regard, ... Nonlinear solution of reinforced concrete structures, particularly complete load-deflection response, requires tracing of the equilibrium path and proper treatment of the limit and bifurcation points. In this regard, ordinary solution techniques lead to instability near the limit points and also have problems in case of snap-through and snap-back. Thus they fail to predict the complete load-displacement response. The arc-length method serves the purpose well in principle, received wide acceptance in finite element analysis, and has been used extensively. However modifications to the basic idea are vital to meet the particular needs of the analysis. This paper reviews some of the recent developments of the method in the last two decades, with particular emphasis on nonlinear finite element analysis of reinforced concrete structures. 展开更多
关键词 Arc-length method Nonlinear analysis Finite element method Reinforced concrete Load-deflection path Document code: A CLC number: TU31 Arc-length technique for nonlinear finite element analysis* MEMON Bashir-Ahmed# SU Xiao-zu (苏小卒) (Department of Structural Engineering Tongji University Shanghai 200092 China) E-mail: bashirmemon@sohu.com xiaozub@online.sh.cn Received July 30 2003 revision accepted Sept. 11 2003 Abstract: Nonlinear solution of reinforced concrete structures particularly complete load-deflection response requires tracing of the equilibrium path and proper treatment of the limit and bifurcation points. In this regard ordinary solution techniques lead to instability near the limit points and also have problems in case of snap-through and snap-back. Thus they fail to predict the complete load-displacement response. The arc-length method serves the purpose well in principle received wide acceptance in finite element analysis and has been used extensively. However modifications to the basic idea are vital to meet the particular needs of the analysis. This paper reviews some of the recent developments of the method in the last two decades with particular emphasis on nonlinear finite element analysis of reinforced concrete structures. Key words: Arc-length method Nonlinear analysis Finite element method Reinforced concrete Load-deflection path
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Combined Adaptive Multiple Subtraction Based on Optimized Event Tracing and Extended Wiener Filtering 被引量:3
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作者 TAN Jun SONG Peng +3 位作者 LI Jinshan WANG Lei ZHONG Mengxuan ZHANG Xiaobo 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第3期411-421,共11页
The surface-related multiple elimination(SRME) method is based on feedback formulation and has become one of the most preferred multiple suppression methods used. However, some differences are apparent between the pre... The surface-related multiple elimination(SRME) method is based on feedback formulation and has become one of the most preferred multiple suppression methods used. However, some differences are apparent between the predicted multiples and those in the source seismic records, which may result in conventional adaptive multiple subtraction methods being barely able to effectively suppress multiples in actual production. This paper introduces a combined adaptive multiple attenuation method based on the optimized event tracing technique and extended Wiener filtering. The method firstly uses multiple records predicted by SRME to generate a multiple velocity spectrum, then separates the original record to an approximate primary record and an approximate multiple record by applying the optimized event tracing method and short-time window FK filtering method. After applying the extended Wiener filtering method, residual multiples in the approximate primary record can then be eliminated and the damaged primary can be restored from the approximate multiple record. This method combines the advantages of multiple elimination based on the optimized event tracing method and the extended Wiener filtering technique. It is an ideal method for suppressing typical hyperbolic and other types of multiples, with the advantage of minimizing damage of the primary. Synthetic and field data tests show that this method produces better multiple elimination results than the traditional multi-channel Wiener filter method and is more suitable for multiple elimination in complicated geological areas. 展开更多
关键词 multiple adaptive attenuation surface-related multiple prediction Wiener filtering short-time window FK filtering event tracing technique
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Fluoro-ruby retrograde tracing and three-dimensional visualization of the corticospinal tract in the guinea pig
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作者 Xiao Han Lulian Xu +7 位作者 Yue Wu Hua Xun Jinxiu Pan Yingying Huang Dafeng Ji Huiqun Wu Guangming Lv Lemin Tang 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第5期363-367,共5页
Fluoro-ruby was injected into the posterior funiculus of the spinal cord in the cervical (C5-T2) and lumbar (L3-6) segments of adult guinea pigs. The spinal cord was cut into serial frozen sections. The Fluoro-rub... Fluoro-ruby was injected into the posterior funiculus of the spinal cord in the cervical (C5-T2) and lumbar (L3-6) segments of adult guinea pigs. The spinal cord was cut into serial frozen sections. The Fluoro-ruby labeling was clearly delineated from the surrounding structure. The labeling traversed the cervical, thoracic and lumbar segments, and was located on the ventral portion of the posterior funiculus on the injected side, proximal to the intermediate zone of the dorsal gray matter. The fluorescence area narrowed rostro-caudally. The spinal cord, spinal cord gray matter and corticospinal tract were reconstructed using 3D-DOCTOR 4.0 software, resulting in a robust three-dimensional profile. Using functionality provided by the reconstruction software, free multi-angle observation and sectioning could be conducted on the spinal cord and corticospinal tract. Our experimental findings indicate that the Fluoro-ruby retrograde fluorescent tracing technique can accurately display the anatomical location of corticospinal tract in the guinea pig and that three-dimensional reconstruction software can be used to provide a three-dimensional image of the corticospinal tract. 展开更多
关键词 corticospinal tract Fluoro-ruby retrograde fluorescent tracing technique three-dimensional reconstruction guinea pig
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Partial Trace Method for Deriving Density Operators of Light Field
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作者 范洪义 唐绪兵 胡利云 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第1期45-48,共4页
With the help of technique of integration within an ordered product of operators we can fully display the partial trace method to deduce some new density operators of light field. The general form of single-mode densi... With the help of technique of integration within an ordered product of operators we can fully display the partial trace method to deduce some new density operators of light field. The general form of single-mode density operator is derived in this way from a normalized two-mode generalized squeezed pure state density operator. 展开更多
关键词 IWOP technique partial trace method two-mode generalized squeezed pure state
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探寻大脑的奥秘:神经示踪技术的发展与应用
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作者 谢浩 高雨欣 +1 位作者 王楠 韩俊海 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第3期789-798,共10页
为了深刻理解神经示踪技术,综述了其演进历程、原理、应用及其在神经科学和其他领域中的应用价值和局限.首先,回顾了传统的神经示踪技术,以肽类标志物、传统染料等为例,分析了顺行和逆行标记2种方法.然后,介绍了用于示踪神经环路的病毒... 为了深刻理解神经示踪技术,综述了其演进历程、原理、应用及其在神经科学和其他领域中的应用价值和局限.首先,回顾了传统的神经示踪技术,以肽类标志物、传统染料等为例,分析了顺行和逆行标记2种方法.然后,介绍了用于示踪神经环路的病毒工具的最新进展,包括狂犬病毒、伪狂犬病毒、单纯孢疹病毒、腺相关病毒等,揭示了其如何帮助理解大脑复杂的工作机制,探讨了其演化历史、类型以及在大脑科学和神经环路研究中的应用价值.最后,展望了神经环路示踪技术在脑连接组学、人类疾病研究和药物开发等领域的发展前景.这些技术的创新将有助于更深入地理解大脑的奥秘,改善神经健康,并应对神经相关疾病的挑战. 展开更多
关键词 神经示踪技术 神经科学 病毒工具 顺行标记 逆行标记
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同位素技术示踪水环境生源要素氮的来源及循环过程研究进展
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作者 任朝斌 王龙 张千千 《水生态学杂志》 CSCD 北大核心 2024年第4期1-8,共8页
氮作为生态系统中的关键生源要素,对于水环境质量和生态系统平衡至关重要。文章综述了同位素技术示踪水环境生源要素氮的来源及循环过程的研究进展。介绍了水环境中氮的主要来源(自然和人为)及时空变化特点,强调自然因素(如降雨)和人为... 氮作为生态系统中的关键生源要素,对于水环境质量和生态系统平衡至关重要。文章综述了同位素技术示踪水环境生源要素氮的来源及循环过程的研究进展。介绍了水环境中氮的主要来源(自然和人为)及时空变化特点,强调自然因素(如降雨)和人为活动(如污水和农业施肥)对水环境中氮分布的影响;详细阐述了同位素技术识别水环境中氮来源的发展历程(单同位素、双同位素和多同位素联合溯源阶段);讨论了同位素技术在辨别水环境中氮循环过程(硝化、反硝化、矿化和同化作用)中的应用;指出当前研究的不足,主要表现在同位素分馏效应、测试成本高、未实测污染源端元值、多种同位素耦合溯源机制不清晰,未来研究需提高同位素溯源技术并整合多类技术与数据,尤其与机器学习结合潜力大。 展开更多
关键词 生源物质 溯源技术 迁移转化 同位素
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用于高功率微波器件粒子模拟的三维柱坐标系共形网格生成技术
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作者 张磊 翁明 +1 位作者 王玥 蒋铭 《强激光与粒子束》 CAS CSCD 北大核心 2024年第4期180-186,共7页
基于面向对象的C++语言研制三维柱坐标共形网格生成程序,对束-场互作用器件作共形网格剖分,为粒子模拟算法提供积分线元、面元。通过定义三维柱坐标网格体系如网格步长、网格索引、守护网格层、包围盒等数据,使模型的空间信息能转换成... 基于面向对象的C++语言研制三维柱坐标共形网格生成程序,对束-场互作用器件作共形网格剖分,为粒子模拟算法提供积分线元、面元。通过定义三维柱坐标网格体系如网格步长、网格索引、守护网格层、包围盒等数据,使模型的空间信息能转换成柱坐标网格信息。将轴上网格单元作特殊处理,使粒子模拟算法形式在轴上网格和在非轴上网格上保持一致。利用射线跟踪法得到属于模型子面、模型棱边的离散边界点,接着通过拓扑关系获得模型的顶点,保存上述三类离散边界点的拓扑信息和网格信息。将构建的基础网格元与边界点信息耦合,在离散网格体系中重构模型。用该共形网格剖分技术对相对论磁控管进行剖分,能够识别该磁控管的透明阴极、阳极和谐振腔等结构。 展开更多
关键词 粒子模拟 三维柱坐标 网格剖分 射线跟踪 共形技术
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脑立体定位斜插法在小鼠小脑蚓部第Ⅸ小叶浦肯野细胞纤维投射研究中的应用
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作者 龚劲雯 杨倩颖 +4 位作者 戴婷 李淑蓉 伍丽娜 苏炳银 赵海霞 《成都医学院学报》 CAS 2024年第2期231-236,共6页
目的 探讨脑立体定位斜插法靶向注射小鼠小脑蚓部第Ⅸ小叶的可行性,并观察该方法对小鼠小脑蚓部第Ⅸ小叶浦肯野细胞纤维的神经投射。方法 利用脑立体定位直插法(进针方向与水平方向垂直)或斜插法(进针方向与水平方向的垂直线呈30°... 目的 探讨脑立体定位斜插法靶向注射小鼠小脑蚓部第Ⅸ小叶的可行性,并观察该方法对小鼠小脑蚓部第Ⅸ小叶浦肯野细胞纤维的神经投射。方法 利用脑立体定位直插法(进针方向与水平方向垂直)或斜插法(进针方向与水平方向的垂直线呈30°夹角)标记Pcp2-Cre小鼠小脑蚓部第Ⅸ小叶,对比两种手术方式对小鼠颈部上方肌肉组织的影响;选择梯度剂量(500、300、150 nL)的顺行示踪病毒,探索适宜的病毒注射剂量;通过斜插法在小鼠小脑蚓部第Ⅸ小叶注射重组酶依赖性顺行示踪病毒,观察该小叶浦肯野细胞的传出神经投射。结果 相较于脑立体定位直插法,斜插法中小鼠头部皮肤切口更小,且不易破坏小鼠颈部上方肌肉;在前囟后6.00 mm、中线旁开0.00 mm、深4.08 mm坐标处,采用斜插法能靶向定位到小脑蚓部第Ⅸ小叶;同时,150 nL低剂量的病毒可较好的标记小脑蚓部第Ⅸ小叶浦肯野细胞,且不发生泄漏;通过病毒顺行示踪,在小鼠小脑顶核中间部、前庭小脑核、前庭内侧核巨细胞部以及前庭下核均检测到来自第Ⅸ小叶浦肯野细胞的神经投射纤维。结论 脑立体定位斜插法能在一定程度上减轻手术对小鼠颈部上方肌肉的破坏,通过该方法注射顺行示踪病毒能精确靶向小脑蚓部第Ⅸ小叶,并观察到该小叶浦肯野细胞的传出神经投射。 展开更多
关键词 小脑蚓部 第Ⅸ小叶 浦肯野细胞 脑立体定位技术 病毒顺行示踪
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多部位示踪技术前哨淋巴结活检在早期子宫内膜癌中的应用
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作者 曲新霞 喇慧 王珂 《临床医学工程》 2024年第7期805-806,共2页
目的探讨多部位示踪技术前哨淋巴结(SLN)活检在早期子宫内膜癌中的应用价值。方法选取我院收治的63例早期子宫内膜癌患者,随机平均分为宫颈注射组、宫体注射组、联合注射组,分别在相应部位注射吲哚菁绿,明确前哨淋巴结的部位及数量,将... 目的探讨多部位示踪技术前哨淋巴结(SLN)活检在早期子宫内膜癌中的应用价值。方法选取我院收治的63例早期子宫内膜癌患者,随机平均分为宫颈注射组、宫体注射组、联合注射组,分别在相应部位注射吲哚菁绿,明确前哨淋巴结的部位及数量,将其切除后送病理检查,再行筋膜外全子宫切除术+双侧附件切除术+腹主动脉旁/盆腔淋巴结清扫术。比较三组SLN敏感度、准确度、假阴性率和阴性预测值。结果检出SLN的51例患者中有18例明确发生淋巴结转移(宫颈注射组3例,宫体注射组4例,联合注射组11例)。联合注射组有1例为腹主动脉旁区域淋巴结转移,属于早期高危型子宫内膜癌,为子宫内膜样癌。联合注射组敏感度、准确度高于宫颈组与宫体组,假阴性率低于宫颈组与宫体组(P<0.05)。结论联合宫颈与宫体作为注射部位能更有效识别盆腔区域SLN,且准确度更高,为术中淋巴结清扫提供积极的指导,对早期子宫内膜癌具有良好的应用价值。 展开更多
关键词 多部位示踪技术 前哨淋巴结 早期子宫内膜癌
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Estimation of wind erosion rates by using ^(137)Cs tracing technique:A case study in Tariat-Xilin Gol transect, Mongolian Plateau 被引量:16
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作者 LIU JiYuan SHI HuaDing +2 位作者 QI YongQing ZHUANG DaFang HU YunFeng 《Chinese Science Bulletin》 SCIE EI CAS 2008年第5期751-758,共8页
Wind erosion is one of the major environmental problems in semi-arid and arid regions. Here we es- tablished the Tariat-Xilin Gol transect from northwest to southeast across the Mongolian Plateau, and selected seven s... Wind erosion is one of the major environmental problems in semi-arid and arid regions. Here we es- tablished the Tariat-Xilin Gol transect from northwest to southeast across the Mongolian Plateau, and selected seven sampling sites along the transect. We then estimated the soil wind erosion rates by using the ^(137)Cs tracing technique and examined their spatial dynamics. Our results showed that the ^(137)Cs inventories of sampling sites ranged from 265.63±44.91 to 1279.54±166.53 Bq·m^(-2), and the wind erosion rates varied from 64.58 to 419.63 t·km^(-2)·a^(-1) accordingly. In the Mongolia section of the transect (from Tariat to Sainshand), the wind erosion rate increased gradually with vegetation type and climatic regimes; the wind erosion process was controlled by physical factors such as annual precipitation and vegetation coverage, etc., and the impact of human activities was negligible. While in the China section of the transect (Inner Mongolia), the wind erosion rates of Xilin Hot and Zhengxiangbai Banner were thrice as much as those of Bayannur of Mongolia, although these three sites were all dominated by typical steppe. Besides the physical factors, higher population density and livestock carrying level should be responsible for the higher wind erosion rates in these two regions of Inner Mongolia. 展开更多
关键词 蒙古高原 风蚀 铯同位素追踪技术 环境恶化
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Tracing the major source area of the mountainous runoff generation of the Heihe River in northwest China using stable isotope technique 被引量:17
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作者 WANG NingLian ZHANG ShiBiao HE JianQiao PU JianChen WU XiaoBo JIANG Xi 《Chinese Science Bulletin》 SCIE EI CAS 2009年第16期2751-2757,共7页
Based on the data of δ18O in precipitation during the period of April 2006 through May 2007 in the upper catchment of the main stream of the Heihe River in the Qilian Mountains, we found that there existed an evident... Based on the data of δ18O in precipitation during the period of April 2006 through May 2007 in the upper catchment of the main stream of the Heihe River in the Qilian Mountains, we found that there existed an evident altitude effect on δ18O in precipitation, and the δ18O-altitude gradient was _0.18‰/100 m. When δ18O in river water at the outlet of the mountainous drainage area of the main stream of the Heihe River was combined with the δ18O-altitude relation, it was realized that the mountainous runoff was generated mostly at high altitudes. Using two component models, we revealed that 80.2% of the annual total mountainous runoff amount was generated at the alpine permafrost-snow-ice zone with an altitude of above 3600 m a.s.l. 展开更多
关键词 山区流域 黑河干流 中国西北地区 径流量 同位素技术 源区 发电 稳定
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Using ^(137)Cs tracing technique to estimate wind erosion rates in the typical steppe region, northern Mongolian Plateau 被引量:8
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作者 QI YongQing LIU JiYuan +2 位作者 SHI HuaDing HU YunFeng ZHUANG DaFang 《Chinese Science Bulletin》 SCIE EI CAS 2008年第9期1423-1430,共8页
Wind erosion is one of the major factors of land degradation in the typical steppe region, northern Mongolian Plateau. Using 137Cs tracing technique, we estimated the wind erosion rates of different pastures and aband... Wind erosion is one of the major factors of land degradation in the typical steppe region, northern Mongolian Plateau. Using 137Cs tracing technique, we estimated the wind erosion rates of different pastures and abandoned farmland at Bayannur and Karakorum in Mongolia. The pastures and cutting grassland at Bayannur were slightly eroded by wind, with the rates of 64.58-169.07 t·km?2·a?1. The abandoned farmland in Karakorum, however, was strongly eroded by wind, with annual surface soil loss of 4.05 mm·a?1, and wind erosion rates up to 6723.06 t·km?2·a?1. The total loss of surface soil due to wind erosion has been 17.4 cm since the cultivation of the steppe land in the 1960s. The wind ero- sion rate at the abandoned farmland was much higher than that at the typical steppe sites, showing that the cultivation led to serious wind erosion in the typical steppe region, northern Mongolian Plateau. By contrast, traditional livestock grazing resulted in less disturbance to the surface soil, and did not in- duce to devastating wind erosion, which plays an important role in maintaining the stability of the steppe ecosystem in the northern Mongolian Plateau. 展开更多
关键词 蒙古高原北部 草原 风蚀 铯元素跟踪技术
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大气痕量气体测量的光谱学和化学技术 被引量:43
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作者 刘文清 崔志成 +4 位作者 刘建国 谢品华 董凤忠 张玉钧 魏庆农 《量子电子学报》 CAS CSCD 北大核心 2004年第2期202-210,共9页
简略评论了大气痕量气体测量的光谱学和化学技术。光谱技术方面重点介绍差分光学吸收光谱(DOAS)、差分吸收激光雷达(DIAL)、傅里叶变换红外光谱学(FTIR)和可调谐半导体激光吸收光谱(TD-LAS),化学测量技术介绍色谱、质谱和色-质联用技术... 简略评论了大气痕量气体测量的光谱学和化学技术。光谱技术方面重点介绍差分光学吸收光谱(DOAS)、差分吸收激光雷达(DIAL)、傅里叶变换红外光谱学(FTIR)和可调谐半导体激光吸收光谱(TD-LAS),化学测量技术介绍色谱、质谱和色-质联用技术、化学发光测量技术、基体分离和电子自旋共振技术以及超声膨胀技术等,并对宽带光谱测量、光谱技术之间、光谱技术与化学技术之间的联用趋势,以及仪器的小型化趋势作了展望。 展开更多
关键词 大气痕量气体 光谱学 测量方法 差分光学吸收光谱 差分吸收激光雷达 傅里叶变换红外光谱学 色谱 质谱
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飞行器轨迹及参数测量的一种新方法 被引量:9
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作者 桂延宁 张福顺 焦李成 《电子学报》 EI CAS CSCD 北大核心 2003年第12期1894-1896,共3页
本文采用GPS定位与遥测技术相结合的方法对中远程飞行器轨迹测量进行了研究 .文中讨论了测量方法实现的基本原理 ,并进行了实验验证 .实验结果表明该方法与其它常规方法相比 ,具有不受气候、目标散射截面以及距离等因素影响的优点 .
关键词 GPS 定位 遥测技术 轨迹测量 飞行器 目标散射截面
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高精度地下水示踪技术及其应用——以毛村地下河流域为例 被引量:40
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作者 何师意 Michele L +2 位作者 章程 汪进良 李强 《地球学报》 EI CAS CSCD 北大核心 2009年第5期673-678,共6页
笔者以桂林毛村岩溶地下河流域的示踪试验为例,探索高精度地下水示踪方法在岩溶水文地质研究中的应用。实践证明,该方法较传统示踪方法具有较大优势。试验中,从地下河主出口回收I号示踪剂为34%,地下水平均流速为35.3m/h,全部回收率约为... 笔者以桂林毛村岩溶地下河流域的示踪试验为例,探索高精度地下水示踪方法在岩溶水文地质研究中的应用。实践证明,该方法较传统示踪方法具有较大优势。试验中,从地下河主出口回收I号示踪剂为34%,地下水平均流速为35.3m/h,全部回收率约为60%~70%。示踪结果证实毛村地下河流域具有典型河间地块特征,存在多个排泄出口,水文地质边界较复杂;主出口处示踪剂浓度变化呈宽域多峰,说明具有多管道、沿途多个较大溶潭特征;II号示踪剂在所有接收点都没有收到,其原因较为复杂和不确定。枯季部分地下水有沿西南方向断层排泄迹象,雨季是否存在较大径流,还需用示踪试验来证实;流量不均衡,排泄区可能存在潜流。 展开更多
关键词 高精度 在线监测技术 地下水示踪 桂林毛村
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RFID技术在食品全程跟踪与追溯中的应用 被引量:28
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作者 张姝楠 郭波莉 潘家荣 《食品研究与开发》 CAS 北大核心 2007年第9期148-151,共4页
简要介绍了射频识别技术(RFID)系统的工作原理与功能特性,综述了RFID技术在食品跟踪与追溯中的国内外研究进展及其与其他溯源技术的区别与联系,并在此基础上指出了制约可追溯系统应用的主要问题,展望了RFID技术在食品领域的应用前景。
关键词 RFID技术 跟踪 追溯 电子标签
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