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A crosstalk-free dual-mode sweat sensing system for naked-eye sweat loss quantification via changes in structural reflectance 被引量:1
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作者 Bowen Zhong Hao Xu +3 位作者 Xiaokun Qin Lingchen Liu Hailong Wang Lili Wang 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期428-438,共11页
Sweat loss monitoring is important for understanding the body’s thermoregulation and hydration status,as well as for comprehensive sweat analysis.Despite recent advances,developing a low-cost,scalable,and universal m... Sweat loss monitoring is important for understanding the body’s thermoregulation and hydration status,as well as for comprehensive sweat analysis.Despite recent advances,developing a low-cost,scalable,and universal method for the fabrication of colorimetric microfluidics designed for sweat loss monitoring remains challenging.In this study,we propose a novel laserengraved surface roughening strategy for various flexible substrates.This process permits the construction of microchannels that show distinct structural reflectance changes before and after sweat filling.By leveraging these unique optical properties,we have developed a fully laser-engraved microfluidic device for the quantification of naked-eye sweat loss.This sweat loss sensor is capable of a volume resolution of 0.5µL and a total volume capacity of 11µL,and can be customized to meet different performance requirements.Moreover,we report the development of a crosstalk-free dual-mode sweat microfluidic system that integrates an Ag/AgCl chloride sensor and a matching wireless measurement flexible printed circuit board.This integrated system enables the real-time monitoring of colorimetric sweat loss signals and potential ion concentration signals without crosstalk.Finally,we demonstrate the potential practical use of this microfluidic sweat loss sensor and its integrated system for sports medicine via on-body studies. 展开更多
关键词 Sweat loss sensor Microfluidic design structural reflectance Dual-mode integration Crosstalk-free
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Wave reflection, transmission and harmonics due to different submerged structures 被引量:1
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作者 Gao Xueping1 Inouchi Kunimitsu2 Kakinuma Tadao3 (1. Hydraulics Institute, Faculty of Civil Engineering, Tianjin University, Tianjin 300072, China 2. Center for Cooperative Research and Development, Ehime University, 3 Bunkyo-cho, Matsuyama 790 - 8577, Japan 3. Nagasaki Comprehensive University, Aba-cho 536, Nagasaki 851 - 0193, Japan) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2000年第2期111-125,共15页
Comparisons of wave reflection, transmission and harmonics due to different types of sub merged structures are investigated by a numerical method, the boundary-fitted coordinate (BFC) method. The types of submerged st... Comparisons of wave reflection, transmission and harmonics due to different types of sub merged structures are investigated by a numerical method, the boundary-fitted coordinate (BFC) method. The types of submerged structures include a submerged horizontal plate, submerged breakwa ters (rectangular and trapezoidal) and a step-type structure (topography). First, the BFC method is ver ified by comparing the computed results with the experimental data, including wave surface elevations, reflected and transmitted wave heights, and amplitudes of higher harmonics, showing that the method is a reasonable one to predict wave deformations due to the submerged structures. Secondly, the wave sur face elevations and the higher harmonics over different submerged structures are compared. Thirdly, re flected and transmitted waves due to different submerged structures are investigated. 展开更多
关键词 Harmonic wave reflected wave transmitted wave submerged structure boundary-fitted coordinate method
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Analysis of Reflection Characteristics for Foam Filled Grid Structure 被引量:1
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作者 徐元铭 徐胜 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第1期1-5,共5页
The reflection characteristics of gird structures are calculated by the spatial network method in the case of normal incidence plane electromagnetic wave. The numerical result shows that the grid panels without electr... The reflection characteristics of gird structures are calculated by the spatial network method in the case of normal incidence plane electromagnetic wave. The numerical result shows that the grid panels without electromagnetic wave absorbing foams are not ideal. However, the absorbing ability can be achieved as low as -25 dBsm from 8 GHz to 12 GHz when the grid cells are filled with foam absorbers. Also it is noted from computation that the foam filled grid structures with larger cell size, higher and thinner ribs will improve the absorbing abilities, which illustrates that they can be used as the effective light-weight stealth structures for aeronautical application. 展开更多
关键词 grid structure spatial network method (SNM) foam reflection characteristics
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POWER REFLECTION AND TRANSMISSION IN BEAM STRUCTURES CONTAINING A SEMI-INFINITE CRACK 被引量:1
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作者 Li Zhou Wanchun Yuan 《Acta Mechanica Solida Sinica》 SCIE EI 2008年第2期177-188,共12页
Wave reflection and transmission in a beam containing a semi-infinite crack are studied analytically based on Timoshenko beam theory., Two kinds of crack surface conditions: non-contact (open) and fully contact (c... Wave reflection and transmission in a beam containing a semi-infinite crack are studied analytically based on Timoshenko beam theory., Two kinds of crack surface conditions: non-contact (open) and fully contact (closed) cracks, are considered respectively for an isotropic beam. The analytical solution of reflection and transmission coefficients for a semi-infinite crack is obtained. The power reflection and transmission ratios depend on both the frequency and the position of the crack. Numerical results show the conservation of power transport. The transmitted energy among various wave modes is also investigated. A finite element method is used to verify the validity of the analytical results. 展开更多
关键词 reflection and transmission CRACK power transport structural health monitoring
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Study on Fine Crustal Structure of the Sanhe-Pinggu Earthquake (M8.0) Region by Deep Seismic Reflection Profiling 被引量:3
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作者 ZhangXiankang ZhaoJinren +7 位作者 LiuGuohua SongWenrong LiuBaojin ZhaoChengbin ChengShuangxi LiuJianda GuMenglin SunZhenguo 《Earthquake Research in China》 2003年第2期122-133,共12页
Two near-vertical deep seismic reflection profiles (140km-long, 24-fold) were completed in the 1679 Sanhe-Pinggu earthquake (M8.0) region. The profiles ran through the Xiadian fault and the Ershilichangshan fault. The... Two near-vertical deep seismic reflection profiles (140km-long, 24-fold) were completed in the 1679 Sanhe-Pinggu earthquake (M8.0) region. The profiles ran through the Xiadian fault and the Ershilichangshan fault. The profiling result shows that the crust in this region is divided into the upper crust, the lower crust and the crust-mantle transitional zone by two powerful laminated reflectors: one at the two-way travel-time of about 7.0s (21km), the other at about 11.0~12.5s (33~37km). Crustal structure varies significantly in vertical direction. The shallow part is characterized by obvious stratification, multilayers and complexity. The upper crust on the whole features reflection “transparency”, while the lower crust features distinct reflectivity. Crustal structure also varies a lot in the lateral direction. The main fracture in this region is the deep fault under the Xiadian fault. This deep fault is steeply inclined (nearly vertical), and is supposed to be the causative fault of the Sanhe-Pinggu M8.0 earthquake. The two profiles respectively reveal the existence of local strong reflectivity in the lower crust and the lower part of the upper crust, which is assumed to be a dike or rock mass formed by the upwelling and cooling down of materials from the upper mantle. Magmatic activity in this part brought about differences in regional stress distribution, which then gave rise to the formation of the deep fault. That is supposed to be the deep structural setting for the Sanhe-Pinggu M8.0 earthquake. 展开更多
关键词 The Sanhe-Pinggu meizoseismal region Deep reflection profiling Fine structure study of earthquake source
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Moho Structure of the Southwest Sub-Basin, South China Sea, from a Multichannel Seismic Reflection Profile NH973-1
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作者 ZHANG Jinchang CHEN Jie HUANG Yanming 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第5期1105-1114,共10页
Moho structure provides important clues for understanding crustal structure,isostatic state and magmatic flux from mantle to surface.Across-basin Moho structure of the South China Sea(SCS)is important for understandin... Moho structure provides important clues for understanding crustal structure,isostatic state and magmatic flux from mantle to surface.Across-basin Moho structure of the South China Sea(SCS)is important for understanding crustal evolution mechanisms of both continental break-up and seafloor spreading processes.Southwest Sub-basin(SWSB)opened up the latest and has the closest continental margins,making it the best to study the across-basin structure.Multichannel seismic(MCS)reflection data of line NH973-1 that crosses SWSB in NW-SE direction were reprocessed in order to image Moho structure.In MCS data,Moho reflectors are observed in places,which were not revealed in prior researches.The Moho generally shows symmetric structure on both sides of the central rift valley(CRV)and with variations in crustal thickness.Around CRV,the Moho is 2 seconds depth in two-way travel time(TWTT)beneath the igneous basement,which corresponds to 7 km depth,indicating normal oceanic crustal accretion during the ending of seafloor spreading.Close to the continent-ocean boundary(COB),the Moho becomes shallow to 1 second depth in TWTT(3.5 km),implying strong crustal thinning towards the continent,probably because of poor magma supply at the beginning of seafloor spreading.At south COB,the Moho depth under the crust almost reaches zero,which could be explained as a result of exhumed mantle.In addition,two low-angle,deep-penetrating normal faults are observed at south COB.The faults cut across the Moho into the upper mantle,which may be attributed to lithospheric hyper-stretching at COB during continental break-up. 展开更多
关键词 MOHO structure MULTICHANNEL seismic reflection CRUSTAL structure South China Sea OCEANIC basin continent-ocean boundary
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Imaging of Hidden Structures from the North Apuseni Mts, Romania, Using Narrow-Angle Seismic Reflection Data
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作者 Ionelia Panea 《Open Journal of Geology》 2020年第1期53-70,共18页
I present results of processing and structural interpretation of narrow-angle seismic reflection data recorded over an area of 30 × 50 km located in the southern part of the North Apuseni Mts, Romania. The invest... I present results of processing and structural interpretation of narrow-angle seismic reflection data recorded over an area of 30 × 50 km located in the southern part of the North Apuseni Mts, Romania. The investigated area is characterized by complex subsurface geology and rough topography. The seismic measurements were performed along five linear profiles, P1-P5, using an active spread of 96 geophones for each shot point;geophone spacing was 25 m. The length of each acquisition line is greater than 10 km. The signal-to-noise ratio of these data varies along the lines and its variation is considered to be an effect of rough topography, complex subsurface geology and varying surface conditions encountered during seismic data acquisition. The data processing was performed using a standard processing flow but with different processing parameters from one data set to another. I obtained five depth-converted migrated seismic sections after data processing. The accuracy of the depth values depends on that of the stacking velocities obtained from the velocity analyses performed on the filtered seismic data. Borehole information is not available, the investigated area belonging to the areas investigated for hydrocarbons. Each seismic section shows a different structural image of the subsurface and provides useful information about the tectonic and stratigraphic evolution of the investigated area. I obtained various structural images of the subsurface after the interpretation of the depth-converted migrated seismic sections, from a simple one with undeformed and inclined reflectors to a complex one with folded and faulted reflectors, especially the older ones. I interpreted intrusive bodies piercing through the overlying sediments, which are in good agreement with the results of older geophysical studies. 展开更多
关键词 structural GEOLOGY TECTONICS reflection SEISMOLOGY reflection Seismic IMAGING
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Impact of the Opto-Geometric Parameters on the Band Diagram and Transmission and Reflection Spectrum of the Bragg Structure
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作者 Iman Ouahab Leila Dekkiche Rafah Naoum 《Optics and Photonics Journal》 2013年第2期184-189,共6页
Knowledge of the band gap and transmission and reflection spectrum of a photonic crystal is essential elements for their design. A graphical interface that quickly determines the banding pattern and spectrum based on ... Knowledge of the band gap and transmission and reflection spectrum of a photonic crystal is essential elements for their design. A graphical interface that quickly determines the banding pattern and spectrum based on the Plane Wave Method (PWM) and coupled modes method (CMM) respectively is created. It is used to explore the behavior of a Bragg structure with the ability to easily vary the important parameters such as refractive indices, number and thickness of layers. 展开更多
关键词 BRAGG structure PWM CMM GRAPHIC User Interface PHOTONIC Band Gap SPECTRUM of Transmission and reflection
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Nanostructured Anti-Reflection Coatings for Enhancing Transmission of Light
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作者 Behnam Kheyraddini Mousavi Arash Kheyraddini Mousavu +2 位作者 Tito Busani Mani Hossein Zadeh S. R. J. Brueck 《Journal of Applied Mathematics and Physics》 2019年第12期3083-3100,共18页
Nanostructured, sub-wavelength anti-reflection layers (NALs) have attracted much attention as a new generation of anti-reflection surfaces. Among different designs, sub-wavelength periodic nanostructures are capable o... Nanostructured, sub-wavelength anti-reflection layers (NALs) have attracted much attention as a new generation of anti-reflection surfaces. Among different designs, sub-wavelength periodic nanostructures are capable of enhancing transmission of coherent light through an interface without inducing scattering. In this work, we have explored a new profile for periodic NALs capable of transmitting IR light with higher efficiency compared to NALs based on a parabolic profile. To achieve high transmission and low diffraction, the profile and pitch of the nanostructured NALs are calculated using a combination of a multi-layer modeling and Rigorous Coupled Wave (RCWA) analysis. 展开更多
关键词 IR EFFECTIVE MEDIUM Theory reflection Laser NANO-structure
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Enhancing Mechanical Stability of Nano-Structured Anti-Reflection Coatings
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作者 Behnam Kheyraddini Mousavi Tito Busani +1 位作者 Mani Hossein Zadeh Steven Roy Julien Brueck 《Journal of Applied Mathematics and Physics》 2020年第2期247-258,共12页
Periodic Nanostructured anti-reflection coatings (NALs) are a promising option for enhancing transmission of coherent light without inducing scattering. We’ve found that reducing the height of NALs below a critical v... Periodic Nanostructured anti-reflection coatings (NALs) are a promising option for enhancing transmission of coherent light without inducing scattering. We’ve found that reducing the height of NALs below a critical value to enhance mechanical stability can highly reduce the transmission efficiency. Here, using Rigorous Couples Wave Analysis (RCWA), we find the minimum height for over 99% transmission and effect of height on transmission bandwidth. Then, during a one-step plasma etching, two samples with different heights have been generated and their efficiency is evaluated using RCWA. 展开更多
关键词 MAXIMUM TRANSMISSION MECHANICAL Stability reflection Laser NANO-structure
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Structural Deformation of Zoigê Basin Along the Deep Seismic Reflection Profile
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作者 Haiyan Wang,Rui Gao,Qiusheng Li,Jisheng Zhang,Zhanwu Lu 1.Lithosphere Research Centre,Institute of Geology,CAGS,Beijing 100037,China. 2.Key Laboratory of Earthprobe and Geodynamics,CAGS,Beijing,100037,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期274-275,共2页
Being the core of the Songpan-Ganze block,Zoig(?) Basin is a favorable zone of oil and gas exploration. And it not only is the important deposition area of the northern Songpan-Garze in the Middle-Late Triassic, but a... Being the core of the Songpan-Ganze block,Zoig(?) Basin is a favorable zone of oil and gas exploration. And it not only is the important deposition area of the northern Songpan-Garze in the Middle-Late Triassic, but also impacts on the formation and evolution of the structural belt.To further understand the Zoig(?) Basin, we reprocessed the 0-20.0 s data of the Tangke-Hezuo deep seismic reflection profiles across the majority 展开更多
关键词 the deep SEISMIC reflection profile structural DEFORMATION MARGIN of the Zoige BASIN
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Structural Characteristics of the Basement beneath Qiangtang Basin in Qinghai-Tibet Plateau: Results of Interaction Interpretation from Seismic Reflection/Refraction Data
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作者 LI Qiusheng GAO Rui +9 位作者 FENG Shaoying LU Zhanwu HOU Hesheng GUAN Ye LI Pengwu WANG Haiyan YE Zhuo XIONG Xiaosong LIU Jinkai HE Rizheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第2期358-377,共20页
The studies on configuration, character/property of the basement of Qiangtang basin is helpful for evaluating petroleum and nature gas resources as well as understanding the basin evolvement. Recently a moderate to hi... The studies on configuration, character/property of the basement of Qiangtang basin is helpful for evaluating petroleum and nature gas resources as well as understanding the basin evolvement. Recently a moderate to high-grade metamorphic gneiss rock was found underlying beneath very low metamorphic Ordovician strata in Mayer Kangri to the north of the central uplift. That fact actually proved existence of the crystalline basement just the distribution and structures of pre-Paleozoic crystalline basement still remain puzzle. In recent years a number of active sources deep seismic profiling, to aim at lithospheric structure of northern Tibet and petroleum resources of the Qiangtang basin, had been conducted that make it possible to image the structure of the basement of the Qiangtang. Near vertical reflection profiles, included those acquired previously and those during 2004 to 2008, have been utilized in this study. By through the interaction process and interpretation between the reflection profiles and the wide-angle profile, a model with the detailed structure and velocity distribution from surface to the depth of 20 km of Qiangtang basin has been imaged.Based on the results and discussions of this study, the preliminary conclusions are as follows: (1) The velocity structure section (~20 kin) that is interactively constrained by the refraction and reflection seismic data reveals that the sedimentary stratum gently lie until 10 km in the south Qiangtang basin. (2) The basement consists of fold basement (the upper) and crystalline basement (the lower).The fold basement buried at the average depth of 6 km with a velocity of 5.2-5.8 km/s. The shallowest appear at range of the central uplift. The crystalline basement is underlying beneath the fold basement at the average depth of 10 km with a velocity of 5.9-6.0 km/s except near Bangong-Nujiang suture. (3) The high-velocity body at the depth range of 3-6 km of the central uplift is considered as a fragment of the crystalline basement that perhaps was raised by Thermal or deformation. (4) The lower-consolidated fold basement show more affinity of Yangtze block but the crystalline basement seems more approximate to Lhasa terrene in geophysical nature. We have attempted to improve the resolution and reliability by interaction of the active seismic data and prove it effective to image complex basement structure. It will be a potential to process the piggy-back acquisition data and has wide prospects. 展开更多
关键词 seismic reflection seismic refraction basement structure Qiangtang basin Qinghai-TibetPlateau
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Tectonic characteristics and structural styles of a continental rifted basin:Revelation from deep seismic reflection profiles 被引量:1
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作者 Yuan Li Yannan Zhao +1 位作者 Zhengliang Lin Qinlin Ma 《Geodesy and Geodynamics》 2016年第5期329-339,共11页
The Fushan Depression is a half-graben rifted sub-basin located in the southeast of the Beibuwan Basin, South China Sea. The Paleogene Liushagang sequence is the main hydrocarbon-bearing stratigraphic unit in the sub-... The Fushan Depression is a half-graben rifted sub-basin located in the southeast of the Beibuwan Basin, South China Sea. The Paleogene Liushagang sequence is the main hydrocarbon-bearing stratigraphic unit in the sub-basin. Using three-dimensional(3-D)seismic data and logging data over the sub-basin, we analyzed structural styles and sedimentary characteristics of the Liushagang sequence. Five types of structural styles were defined: ancient horst, traditional slope, flexure slope-break, faulted slope-break and multiple-stage faults slope, and interpretations for positions, background and development formations of each structural style were discussed. Structural framework across the sub-basin reveals that the most remarkable tectonic setting is represented by the central transfer zone(CTZ) which divides the sub-basin into two independent depressions, and two kinds of sequence architectures are summarized:(i) the western multi-stage faults slope;(ii) the eastern flexure slope break belt. Combined with regional stress field of the Fushan Depression, we got plane combinations of the faults, and finally built up plan distribution maps of structural system for main sequence. Also, we discussed the controlling factors mainly focused on subsidence history and background tectonic activities such as volcanic activity and earthquakes. The analysis of structural styles and tectonic evolution provides strong theoretical support for future prospecting in the Fushan subbasin and other similar rifted basins of the Beibuwan Basin in South China Sea. 展开更多
关键词 South China Sea Continental rifted basin structural style 3-D seismic-reflection Seismic geomorphology
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Application of the equivalent offset migration method in acoustic log reflection imaging 被引量:6
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作者 张铁轩 陶果 +2 位作者 李君君 王兵 王华 《Applied Geophysics》 SCIE CSCD 2009年第4期303-310,393,共9页
Borehole acoustic reflection logging can provide high resolution images of nearborehole geological structure. However, the conventional seismic migration and imaging methods are not effective because the reflected wav... Borehole acoustic reflection logging can provide high resolution images of nearborehole geological structure. However, the conventional seismic migration and imaging methods are not effective because the reflected waves are interfered with the dominant borehole-guided modes and there are only eight receiving channels per shot available for stacking. In this paper, we apply an equivalent offset migration method based on wave scattering theory to process the acoustic reflection imaging log data from both numerical modeling and recorded field data. The result shows that, compared with the routine post-stack depth migration method, the equivalent offset migration method results in higher stack fold and is more effective for near-borehole structural imaging with low SNR acoustic reflection log data. 展开更多
关键词 acoustic reflection logging common scatter point gather signal processing nearborehole structure imaging
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Crustal structure in northern margin of Tianshan mountains and seismotectonics of the 1906 Manas earthquake 被引量:38
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作者 王椿镛 楼海 +1 位作者 魏修成 吴庆举 《地震学报》 CSCD 北大核心 2001年第5期460-470,共11页
长86 km、南北向横跨乌鲁木齐坳陷的深地震反射剖面,揭示了北天山山前地壳的薄皮构造特征.共深度点叠加剖面的石河子以南部分显示了天山北缘平行山体的第一和第二排背斜构造.与双程时间分别为2.5~3.0s和5.5~6.0s的反射事件对应的滑脱... 长86 km、南北向横跨乌鲁木齐坳陷的深地震反射剖面,揭示了北天山山前地壳的薄皮构造特征.共深度点叠加剖面的石河子以南部分显示了天山北缘平行山体的第一和第二排背斜构造.与双程时间分别为2.5~3.0s和5.5~6.0s的反射事件对应的滑脱构造,将地壳深部构造与地表逆断裂-褶皱构造联系在一起.玛纳斯断裂以铲形方式向下延伸,在2.5s左右深度归并于第一滑脱面,向南与清水河断裂汇合.在5.5~6.0s深度上为与玛纳斯下背斜相连的主滑脱面.它们最终汇集到准噶尔南缘断裂.石河子以北的坳陷沉积深度达12~14km.沿剖面的莫霍界面深度在准噶尔盆地为45km左右,往南加深至50km.对该区域内的深地震测深剖面和布格重力异常资料的分析结果,与深反射剖面的地壳结构图象具有一致性.深地震反射剖面通过1906年玛纳斯7.7级地震宏观震中区,共深度点叠加剖面用于推断玛纳斯7.7级地震与北天山山前地壳构造之间的关系:玛纳斯地震属于一类“褶皱地震”,其发震构造是由准噶尔南缘断裂、清水河逆冲断裂、滑脱面和玛纳斯浅部断坡组成的断层系. 展开更多
关键词 地壳结构 深地震反射剖面 逆断层-褶皱带 玛纳斯地震区 地震构造
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A method to study interactions between narrow-banded random waves and multi-chamber perforated structures 被引量:9
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作者 Zhenhua Huang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第4期285-292,共8页
A time-domain method, based on linear velocity potential theory, is presented to study the interaction between narrow-banded random waves and perforated structures. A simple relation is derived to estimate the jet len... A time-domain method, based on linear velocity potential theory, is presented to study the interaction between narrow-banded random waves and perforated structures. A simple relation is derived to estimate the jet length of flows through the perforated wall. The reflection coefficient of narrow banded random waves from perforated structures is calculated by assuming a Rayleigh distribution of the heights of incident random waves. For reflection of narrow-banded waves from a single-chamber perforated breakwater, a comparison of the predicted and measured reflection coefficients shows that the method presented in this paper can provide a prediction better than that of regular waves. Numerical results are also reported on the reflection of narrow-banded waves from multi-chamber perforated breakwaters. 展开更多
关键词 Surface waves Narrow-banded randomwaves Perforated structures Wave reflection
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Selective reflection combined with Fabry-Perot effects from two-level atoms confined between two dielectric walls 被引量:6
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作者 李院院 周瑜 张贵忠 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第5期985-991,共7页
The coefficient of selective reflection at oblique incidence from two-level atoms confined between two dielectric walls is calculated in this paper. It is found to be related to the transient behaviour of atoms after ... The coefficient of selective reflection at oblique incidence from two-level atoms confined between two dielectric walls is calculated in this paper. It is found to be related to the transient behaviour of atoms after colliding with the wall and the distribution of the field inside the vapour corresponds to L/λ, with L the thickness of the film and λ the incident wavelength. We find that the sub-Doppler structure is manifest both for normal incidence and small angle oblique incidence, It is feasible to detect the real part of selective reflection in several cases that have not been achieved before. 展开更多
关键词 selective reflection confined atomic vapour film sub-Doppler structure
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A DEEP SEISMIC REFLECTION PROFILE ACROSS ALTUN FAULT BELT 被引量:3
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作者 Gao Rui 1, Liu Hongbin 2, Li Qiusheng 1,Li Pengwu 1, Yao Peiyi 1, Huang Dongding 3 (1 Lithosphere Research Center, Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China,E\|mail: gaorui@cags.cn.net 2 Institute of Ge 《地学前缘》 EI CAS CSCD 2000年第S1期205-205,共1页
Altun fault is regarded as a large\|scale sinistral strike\|slip fault, it is composed of several faults with the different character, and there is a special geological structure in the fault belt, and they constitute... Altun fault is regarded as a large\|scale sinistral strike\|slip fault, it is composed of several faults with the different character, and there is a special geological structure in the fault belt, and they constitute the northwestern margin fault belt of the Qinghai\|Tibetan plateau. In order to investigate the deep crust structure in the Altun region, layers which Tarim lithosphere subducted beneath the Qinghai\|Tibetan plateau, the forward structure of the subduction plate and the scale of the plate subduction, a deep seismic reflection profile was designed. Data collection work of the deep seismic reflection profile across Altun fault was completed during 24/8/1999 to 25/9/1999. The profile locates in Qiemo county, Xinjiang Uygur Autonomous Region, the southern end of the profile stretches into Altun Mountains, the northern end locates in the Tarim desert margin. The profile is nearly SN trending and crosses the main Altun fault. The profile totally is 145km long, time record is 30 seconds, the smallest explosive amount is 72~100kg, the biggest explosive amount reaches 200~300kg, the explosive distance is 800m, and detectors are laid at a 50m distance. 展开更多
关键词 DEEP seismic reflection probing Altun FAULT BELT TARIM b lock DEEP CRUST structure MOHO
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Study on crust-mantle tectonics and its velocity structure along the Beijing-Huailai-Fengzhen profile 被引量:4
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作者 祝治平 张先康 +3 位作者 张建狮 张成科 赵金仁 徐朝凡 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第5期62-70,共9页
In order to investigate the interrelations of crust and upper mantle tectonics and its velocity distribution as well as seismicity in the Yanhuai basin and its surrounding area, a nearly EW trending Beijing Huailai ... In order to investigate the interrelations of crust and upper mantle tectonics and its velocity distribution as well as seismicity in the Yanhuai basin and its surrounding area, a nearly EW trending Beijing Huailai Fengzhen wide angle reflection/refraction profile, which obliquely passes through seismic zone of Zhangjiakou Bohai Sea and coincides with a deep reflection profile in the Yanhuai basin, was completed recently. The results show: The crust presents layered structures and its thickness gradually increases from 35.0 km in Shunyi to 42.0 km in the west end of the profile; the interior crustal interfaces appear approximately horizontal or slowly sloping down from east to west; In the Yanhuai basin, the crust presents the characteristics of higher velocities alternating with the lower ones and the low velocity bodies obviously exist in the lower part of upper crust. Moreover, there are two deep crustal fault zones which stretch to the Moho discontinuity, are closely related with the seismicity in the Yanhuai area. 展开更多
关键词 CRUST mantle velocity structure deep crustal fault wide angle reflection/refraction
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Analysis of Wave Height in Front of a Wave Absorbing Structure with Rubble Foundation 被引量:2
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作者 Li Rongqing Xie Shileng Engineer, The First Design Institute of Navigation Engineering, The Ministry of Communications, Tianjin Professor and Senior Engineer, Deputy Chief Engineer, The First Design Institute of Navigation Engineering, The Ministry of Communications, Tianjin 《China Ocean Engineering》 SCIE EI 1992年第3期251-264,共14页
Wave absorbing structures have been widely applied in many countries. In the present paper, the wave heights in front of a vertical wave absorbing structure with rubble foundation as well as in the wave chamber of the... Wave absorbing structures have been widely applied in many countries. In the present paper, the wave heights in front of a vertical wave absorbing structure with rubble foundation as well as in the wave chamber of the structure are analysed using an approximative calculation method, and the dissipating effect of the structure is verified. On the basis of the results of regular waves, the relative wave heights of irregular waves in front of the wave absorbing structure as well as in the chamber have also been analysed. 展开更多
关键词 wave absorbing structure reflection coefficient wave height analysis irregular waves
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