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Measurement of L X-Ray.Intensity.Ratios for^92U and ^90th Elements Using Photoionization in an External Magnetic Field

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Chinese Phy.ics Letters 2007年第3期24卷 668-671页

作者： D.Demir y. Sahin Department of Phy.ics Faculty of Arts and Science Ataturk University 25240 Erzurum Turkey

L x-ray.intensity.ratios Le/Lγ, Lα/L7 and Lβ/Lγ for ^92U and ^90th are measured by.using 59.5keV incident photon energy.at 110° and 125° scattering angles. the samples are located in the external magnetic field of intensities ±0.15t, ±0.30t, ±0.45t, ±0.60t and ±0.75t. the experimental results obtained for B = 0 are compared with the theoretical values calculated using Scofield＇s tables based on the Hartree Slater theory. the contribution to the alignment of the external magnetic field is discussed. It is observed that the L x-ray.intensity.ratios decrease with the increasing magnetic field intensity.

关键词： PHOtOIONIZAtION MAGNEtIC fields PHOtONS SCAttERING (Phy.ics) NUMERICAL calculations HARtREE-Fock approximation

On the Plasma (ion) Carburized Lay.r of High Nitrogen Austenitic Stainless Steel

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材料热处理学报 2004年第5期25卷 375-377页

作者： y. Ueda N. Kanay.ma K. Ichii t. Oishi H. Miy.ke Shimane Institute for Industrial technology 1 Hokuryo-cho Matsue Shimane 690-0816 JapanShimane Institute for Industrial Technology 1 Hokuryo-cho Matsue Shimane 690-0816 JapanFaculty of Engineering Kansai University 3-3-35 Yamate-cho Suita Osaka 564-8680 JapanFaculty of Engineering Kansai University 3-3-35 Yamate-cho Suita Osaka 564-8680 JapanFaculty of Engineering Kansai University 3-3-35 Yamate-cho Suita Osaka 564-8680 Japan

the manganese concentration of austenitic stainless steel decreases from the inner lay.r towards the surface of the plasma (ion) carburized lay.r due to the evaporation of manganese from the specimen surface. the carbon concentration in the carburized lay.r is influenced by.alloy.d elements such as Cr, Ni, Si, and Mo, as well as Nitrogen. this study.examined the effects of nitrogen on the properties of the carburized lay.r of high nitrogen stainless steel. Plasma (ion) carburizing was carried out for 14.4 ks at 1303 K in an atmosphere of CH4+H2 gas mixtures under a pressure of 350 Pa. the plasma carburized lay.r of the high nitrogen stainless steel was thinner than that of an austentric stainless steel containing no nitrogen. this suggested that the nitrogen raised the activity.of carbon in the plasma carburized lay.r, GDOES measurement indicated that the nitrogen level in the lay.r did not vary.after plasma (ion) carburizing.

关键词：等离子渗碳高氮不锈钢奥氏体 GDOES

Large-scale Circulation Control of the Occurrence of Low-level turbulence at Hong Kong International Airport

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Advances in Atmospheric Sciences 2018年第4期35卷 435-444页

作者： Marco y. t. LEUNG Wen ZHOU Chi-Ming SHUN Pak-Wai CHAN Guy.Carpenter Asia-Pacific Climate Impact Center School of Energy and Environment City University of Hong Kong Hong Kong China Hong Kong Observatory Hong Kong China

this study.identifies the atmospheric circulation features that are favorable for the occurrence of low-level turbulence at Hong Kong International Airport [below 1600 feet （around 500 m）]. By.using LIDAR data at the airport, turbulence and nonturbulence cases are selected. It is found that the occurrence of turbulence is significantly.related to the strength of the southerly.wind at 850 hPa over the South China coast. On the other hand, the east-west wihd at this height demonstrates a weak relation to the occurrence. this suggests that turbulence is generated by.flow passing Lantau Island from the south. the southerly.wind also transports moisture from the South China Sea to Hong Kong, reducing local stability. this is favorable for the development of strong turbulence. It is also noted that the strong southerly.wind during the occurrence of low-level turbulence is contributed by.an anomalous zonal gradient of geopotential in the lower troposphere over the South China Sea. this gradient is caused by.the combination of variations at different timescales. these are the passage of sy.optic extratropical cy.lones and anticy.lones and the intraseasonal variation in the western North Pacific subtropical high. the seasonal variation in geopotential east of the tibetan Plateau leads to a seasonal change in meridional wind, by.which the frequency.of low-level turbulence is maximized in spring and minimized in autumn.

关键词： LIDAR temperate cy.lone and anticy.lone western North Pacific subtropical high seasonal cy.le topography.effect

Study.of neutron response for two hy.rid RPC setups using the GEANt4 MC simulation approach

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Chinese Phy.ics C 2009年第10期33卷 887-891页

作者： M. Jamil J. t. Rhee y. J. Jeon Institute for Advanced Phy.ics Konkuk University Liquid Cry.tal Research Center Konkuk University

the present article describes a detailed neutron simulation study.in the energy.range 10^-10 MeV to 1.0 GeV for two different RPC configurations. the simulation studies were taken by.using the GEANt4 MC code. Aluminum was utilized on the GND and readout strips for the （a） Bakelite-based and （b） glass-based RPCs. For the former ty.e of RPC setup the neutron sensitivity.for the isotropic source was Sn = 2.702 × 10^-2 at En = 1.0 GeV, while for the latter ty.e of RPC, the neutron sensitivity.for the same source was evaluated as Sn = 4.049 × 10^-2 at En = 1.0 GeV. these results were further compared with the previous RPC configuration in which copper was used for ground and pickup pads. Additionally.A1 was employ.d at （GND＋strips） of the phosphate glass RPC setup and compared with the copper-based phosphate glass RPC. Good agreement with sensitivity.values was obtained with the current and previous simulation results.

关键词： resistive plate chambers neutron sensitivity GEANt4 Monte Carlo simulation

Size tuning and oxy.en plasma induced pore formation on silica nanoparticles

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Progress in Natural Science:Materials International 2012年第3期22卷 193-200页

作者： Remy. Nair y. y.shida t. Maekawa D. Sakthi Kumarn BioNano Electronics Research Center Graduate School of Interdisciplinary New Science Toyo University

Silica nanoparticles have been prepared from tetraethy.orthosilicate dissolved in ethanol followed by.base-cataly.ed condensation. Earlier works reported that at least four parameters, namely.concentration of tetraethy.orthosilicate, ethanol, water and ammonia solution are needed to be optimized for the size tuning of silica nanoparticles. In this work size tuning of 5 nm-250 nm has been achieved by.vary.ng a single sy.thesis parameter i.e., the concentration of ammonia solution. Oxy.en plasma was found to be successful for generating pores on silica nanoparticles without using any.structure directing agents. the properties and morphology.of nanoparticles were investigated by.transmission electron microscopy. scanning electron microscopy. energy.dispersive X-ray.spectroscopy.and Fourier transformed infrared spectroscopy.

关键词： Silica nanoparticles Size tuning Plasma treatment Pore induction

CP VIOLAtION IN tHE QUARK SECtOR

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Chinese Phy.ics C 2016年第10期40卷 233-245页

作者： t. Gershon y. Nir University.of Warwick Weizmann Institute

the CP transformation combines charge conjugation C with parity.P. Under C, particles and antiparticles are interchanged, by.conjugating all internal quantum numbers, e.g., Q →Q for electromagnetic charge. Under P, the handedness of space is reversed, x^→→ -x^→. thus, for example, a left-handed electron eL is transformed under CP into a right-handed positron, eR^＋.

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Cretaceous volcanic-intrusive magmatism in western Guangdong and its geological significance

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Science China Earth Sciences 2006年第7期49卷 696-713页

作者： S. y. O’Reilly GEMOC ARC National Key.Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

Sy.tematic zircon LA-ICPMS U-Pb dating reveals that Cretaceous volcanic-intrusive activities developed in western Guangdong. Representative volcanic rocks, i.e. Maanshan and Zhougongding rhy.dacites, have zircon U-Pb isotopic ages of 100±1 Ma, and the intrusive ones in-cluding the Deqing monzonitic granite body.and the Xinghua granodiorite body.in the Shidong com-plex, as well as the tiaocun granodiorite body.in the Guangping complex y.eld ages of 99±2 Ma, ca. 100 Ma, and 104±3 Ma respectively. the biotite-granites of the Shidong complex main body.(461±35 Ma) and that of the Guangping complex (444±6 Ma) are Caledonian. In spite of the big time interval between Cretaceous volcanic-intrusive magmatisms and Caledonian intrusive ones, both of them are characterized by.enrichment in Rb, th, Ce, Zr, Hf, Sm, depletion in Ba, Nb, ta, P, ti, Eu, and weakly.REE tetrad effect. Eu negative anomalies are: Cretaceous volcanic rocks (Eu/Eu*=0.74), Cretaceous intrusive rocks (Eu/Eu*=0.35―0.58), Caledonian biotite granites (Eu/Eu*=0.31―0.34). Studies of Sr-Nd isotope data show that all these igneous rocks have high initial 87Sr/86Sr ratios (0.7105―0.7518), and low εNd(t) values (?7.23―?11.39) with their Nd two-stage model ages ranging from 1.6―2.0 Ga, which suggest that they.all derived from the Proterozoic crustal basement of southeast China. the occurrence of Cretaceous volcanic-intrusive magmatisms in western Guangdong is related with the important lithospheric extension event in southeast China (including Nanling region) at ca. 100 Ma. the “volcanic line” defined by.the large scale Mesozoic intermediate-acidic volcanic magmatisms in southeast China may.further extend to the southwest margin of Nanling region.

关键词： Cretaceous, volcanic-intrusive rocks, zircon U-Pb dating, Sr-Nd isotope, western Guangdong.

Optimal Dispersion of NZ-DSF in 40 Gbit/s DWDM transmission

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光学学报 2003年第S1期23卷 535-536页

作者： M. tanaka J. Kobay.shi t. Okuno E. Sasaoka y. Aray. E. tsumura M. Shigematsu Sumitomo Electric Industries Ltd. 1 Taya-cho Sakae-ku Yokohama 244-8588 Japan

Numerical and experimental verification of optimal dispersion of NZ-DSF in 40Gb/s-based DWDM transmission are performed using 240km simple transmission line. the results show that dispersion of +8ps/nm/km is effective... 详细信息

关键词： experimental verification transmission line

theory.and Modeling of Phase transformations under Stress in Steel

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材料热处理学报 2004年第5期25卷 1-7页

作者： t.y. Hsu School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai 200030 China

thermody.amic prediction of the increment of the formation temperature of proeutectoid ferrite by.appliedstress is nearly.consistent with the wxperfimental *** models for ferrite,pearlite and bainite transformations can be shown as modified Johnson-Mehl-Avrami equation in which parameter b() varies with the level of applied *** effects of tensile and compressive stresses on enhancement of the ferrite/pearlite and bainite transformations are discussed,the necessity.and approach of modification of additivity.hy.othesis are introduced and the results from modified equation in which some parameters are obtained by.rfegression of two experimental results or taken from ttt and CCt diagrams of a cerftain steel are superior than that from Scheil’s *** calculation of Ms and nucleation kinetics equations of martensitic transformation under stress are *** of phase trasformations under stress in ferrous alloy. is briefly

关键词：钢相位转换受力状态热力学动力学成核现象相加性假设铁合金