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Dynamics of moisture regime and its reconstruction from a tree-ring width chronology of Pinus sylvestris in the downstream basin of the Selenga River, Russia

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Journal of Arid Land 2018年第6期10卷 877-891页

作者： Liliana BELOKOPYTOVA Dina ZHIRNOVA Tatiana KOSTYAKOVA Elena BABUSHKINA Khakass technical institute Siberian Federal University

Regional tree-ring width chronology of the Scots pine (Pinus sylvestris L.) was constructed from 8 sites in the forest-steppe belt situated in the foothills of the Selenga River basin, Russia. Moisture information contained in tree-ring width chronology was obtained through linear regression reconstruction models of annual August–July precipitation and annual water discharge of the Selenga River during the period 1767–2015. Comparison of the smoothed series allowed estimating long-term variation component of these moisture regime parameters with a high precision. At the same time, regional drought indices are less correlated with pine radial growth, because they have contribution of the other environmental variables, which are much less reflected in the tree-ring of the investigated pine forest stands. Reconstructed dynamic of the moisture regime parameters is supported by documental evident of many socially significant events in the regional history, such as crop failures caused by both droughts and floods, and catastrophic fire in the Irkutsk City in 1879. Also, dependence of the amount of precipitation in the study area on the atmospheric circulation in Central Asia is revealed to have a similar pattern with other regions, i.e., a negative relationship of precipitation with the development of large high atmospheric pressure area within its center in the Altai and Tianshan mountains.

关键词： tree-ring width Pinus sylvestris climate hydrology precipitation reconstruction model

Numerical simulation of the sticking process of glass-microparticles to a fiat wall to represent pollutant-particles treatment in a multi-channel cyclone

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Particuology 2017年第3期15卷 112-131页

作者： Raimondas Jasevicius Harald Kruggel-Emden Pranas Baltrenas institute of Mechanical Science Vilnius Gediminas Technical University Lithuania Research institute of Environmental Protection Vilnius Gediminas Technical University Lithuania Department of Mechanical Process Engineering and Materials Processing Technical University Berlin Germany

Ultrafine particles are dangerous to human health and are usually difficult to separate from airflow because of their low inertia, which helps them to stick easily to surfaces because of adhesive forces. This characteristic provides opportunities for adhesive ultrafine particle separation by designing air-cleaning devices that exploit the sticking ability. To understand governing effects in such air-cleaning devices, which can be designed as multi-channel cyclones, the sticking of adhesive spherical glass particles under oblique impact has been investigated numerically by using the discrete element method. An adhesive dissipative contact model was applied by implementing different interaction forces for various-sized ultraflne pollutant particles. Normal loading is represented by the elastic Hertz contact model, whereas viscous damping is described by the modified nonlinear Tsuji model. The influence of deformation- dependent adhesive forces for a range of ultrafine particle sizes is illustrated during the sticking process. Dissipative oscillations during the sticking process were observed because of the influence of viscous damping forces.

关键词： Adhesion Discrete element method Microparticles Multi-channel cyclone Sticking process Boundary layer

Experimental and finite element analyses on the corrosion of underground pipelines

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Science China(Technological Sciences) 2015年第6期58卷 1015-1020页

作者： SUN Li CHEN Chen SUN QianQian School of Civil Engineering Shenyang Jianzhu University Liaoning urban Architectural Design institute

Underground pipelines, on which a city relies for survival and development, have become an important part of lifeline engineering. Underground pipelines are utilized for conveying liquid, gas or loose solid, pipeline leakage and damage occasionally resulting from corrosion. Corrosion monitoring of underground pipelines is aimed at ensuring their normal operation and preventing loss of life and property. In this paper, a new method to monitor corrosion of pipelines has been proposed to solve the mentioned problem. Under the influence of internal pressure and corrosion, the pipeline wall becomes thinner and the circumferential deformation increases. The method is to indirectly investigate pipeline corrosion by monitoring the circumferential deformation. Numerical simulation confirms that the circumferential strain curve of the pipeline wall measured by using the proposed method to describe the corrosion is feasible. The proposed method provides a new way for real-time and long-term monitoring and management of underground pipelines.

关键词： underground pipeline fiber bragg grating sensor corrosion monitoring

Conservation and tourism development of house settlements in Moso matriarchate in Lugu Lake area

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Frontiers of Structural and Civil Engineering 2009年第2期3卷 204-210页

作者： Yaoyun XING Zhujiu XIA Jian DAI College of Architecture and urban management Beijing University of TechnologyBeijing 100022China institute of Architecture and urban&Rural Research Taiwan UniversityTaipei 106China

This paper analyzes the present situation of the settlement and the influence of tourism development and *** discusses the attitude toward the conservation and development of the settlement as well as the way to maintain the production,life,and culture of the Mosian and the way to promote the sustainable development of the settlement by tourism.

关键词： Moso matriatchate home conservation of settlement tourism development

Laser-induced breakdown spectroscopy based detection of lunar soil simulants for moon exploration

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Chinese Optics Letters 2007年第1期5卷 58-59页

作者：舒嵘亓洪兴吕刚马德敏何志平薛永祺 Shanghai institute of technical Physics Chinese Academy of Science

A scientific goal of the moon exploration project is to perform elemental analysis on the moon surface. The assuming of using laser-induced breakdown spectroscopy （LIBS） for this goal has been put forward. The laser plasma used by LIBS is sensitive to the surrounding atmosphere and the moon has very low ambient gas pressure on the surface, so the study of the LIBS capabilities at the low pressure was carried out.

关键词： Chemical analysis

Crosstalk of HgCdTe LWIR n-on-p diode arrays

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Journal of Semiconductors 2009年第9期30卷 49-52页

作者：孙英会张波于梅芳廖清君张燕文鑫姜偑璐胡晓宁戴宁 Shanghai institute of technical Physics Chinese Academy of Sciences

Crosstalk of HgCdTe long-wavelength infrared （LWIR） n-on-p diode arrays was measured using scanning laser microscopy. During the measurement, HgCdTe diode arrays with different diode pitches were frontside illuminated by a He-Ne laser at liquid nitrogen temperature and room temperature. The experimental results show that crosstalk between the nearest neighboring diodes decreases exponentially as the diode pitch increases, and the factors that affect the obtained crosstalk are presented and analyzed. Crosstalk out of the nominal diode area （optically sensitive area） is also measured and discussed.

关键词： crosstalk HgCdTe n-on-p diode arrays scanning laser microscope

Synthesis,Structure and Luminescent Properties of Polymeric Copper(Ⅰ) Halide Complexes Bearing Phosphine and N-donor Bridging Ligands

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Chinese Journal of Structural Chemistry 2007年第10期26卷 1179-1183页

作者：于明明赵希娟傅文甫 technical institute of Physics and Chemistry The Chinese Academy of Sciences

Three polymeric copper（Ⅰ） halide complexes beating phosphine and N-donor bridging ligands, [（PPh3）2Cu2（μ-Br）2（μ-4,4＇-bipy）]∞ 1 （bipy = bipyridine）, [（PPh3）2Cu2（μ-Br）2（μ- bpe）]∞ 2 （bpe = trans-1,2-bis（4-pyridyl）ethene） and [（PPh3）2Cu2（μ-Cl）2（μ-bpe）]∞ 3, were synthesized by the multilayer diffusion method, and the structures were refined by single-crystal X-ray diffraction. Complex 1 crystallizes in triclinic, space group P1^- with a = 9.122（3）, b = 9.322（3）, c = 13.201（4） A, α = 106.440（4）, β= 105.965（5）, γ= 94.167（5）°, V = 1021.3（6） A^3, Mr= 967.62, Z = 1, De= 1.573 g/cm^3, F（000） = 486, μ = 3.111 mm^-1, the final R = 0.0383 and ωR = 0.0960 for 2792 observed reflections （I 〉 2σ（I））. Complex 2 crystallizes in triclinic, space group P1^- with a = 9.420（3）, b = 10.209（4）, c = 12.407（4） A, α = 104.136（6）, β = 108.132（5）, γ= 95.338（6）°, V = 1081.0（7） A^3, Mr= 496.83, Z = 2, Dc= 1.526 g/cm^3, F（000） = 500, μ = 2.941 mm^-1, the final R = 0.0445 and ωR = 0.1117 for 3251 observed reflections （I 〉 2σ（I））. Complex 3 crystallizes in triclinic, space group P1^- with a = 8.32（1）, b = 11.53（2）, c = 13.94（3） A, α = 109.57（3）, β= 93.85（3）, γ= 97.28（3）°, V= 1242（4） A^3, Mr= 1074.59, Z = 1, Dc = 1.436 g/cm^3, F（000） = 548, μ = 1.279 mm^-1, the final R = 0.0786 and ωR = 0.1586 for 2266 observed reflections （I 〉 2σ（I））. The complexes exhibit intensive solid-state photoluminescence tentatively assigned to an admixture of triplet intraligand （IL） and metal-to-ligand charge-transfer （MLCT） excited state.

关键词： copper(Ⅰ) complex mixed-ligand crystal structure photolumineseenee polymers

Some New Transition Classes in the Fractional Quantum Hall Effect and Their Critical Filling Factors

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Chinese Physics Letters 1996年第3期13卷 215-218页

作者： CHEN Ying-jian institute of Scientific and technical Information of China Beijing 100038

The transitions between fractional quantum Hall states are classified into three equivalence classes by virtue of the matrix *** is pointed out that there probably exist two new transition classes and the critical fil... 详细信息

关键词： theory. transitions Transition

HB-2 high-velocity correlation model at high angles of attack in supersonic wind tunnel tests

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Chinese Journal of Aeronautics 2019年第7期32卷 1565-1576页

作者： Djordje VUKOVI? Dijana DAMLJANOVI? Department of Experimental Aerodynamics Military Technical InstituteVojnotehnicki Institut

Responding to a need for experimental data on a standard wind tunnel model at high angles of attack in the supersonic speed range, and in the absence of suitable reference data, a series of tests of two HB-2 standard models of different sizes was performed in the T-38 trisonic wind tunnel of Vojnotehnickˇi Institut(VTI), in the Mach number range 1.5–4.0, at angles of attack up to+30°. Tests were performed at relatively high Reynolds numbers of 2.2 millions to 4.5 millions(based on model forebody diameter). Results were compared with available low angle of attack data from other facilities, and, as a good agreement was found, it was assumed that, by implication, the obtained high angle of attack results were valid as well. Therefore, the results can be used as a reference database for the HB-2 model at high angles of attack in the supersonic speed range, which was not available before. The results are presented in comparison with available reference data, but also contain data for some Mach numbers not given in other publications.

关键词： Base pressure Experimental aerodynamics High angle of attack Standard model Wind tunnel