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Asphalt　fractions　in　airborne　particles　from　highway　traffic　and　the　accumulation　in　plants

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Journal of Environmental Sciences 1996年第2期8卷 196-202页

作者： He Kebin(Department of Environmental Engineering, Tsinghua University, Beijing 100084,China)Hans Mosbaek Jens Chr. Tjell(Department of Environmental Engineering,Technical University of Dentnark, 2800 Lyngby,Denmark) dept. of Environmental Engineering Tsinghua University Beijing 100084 China dept. of Environmental Engineering Technical University of Denmark 2800 Lyngby Denmark

With reference to ASTM D4124, asphalt fractions, including polar aromatics (polars),naphthene aromatics (aromatics) and saturates,were characterized both in airborne particles collected in the distances of 2.0 -83.6m from the highway and in the plant samples (including grass,leaves and wheat straw) collected in the distance of 2.0 -10. 0m from the highway. In comparison to the results of diesel particulate, background plant samples and asphalt cernent samples from highway surface, it is concluded that there could be asphalt rnatters in airborne particles and asphalt makes the rnain contributions to the accumulation of the three factions mentioned above in plant species. In the ambient air,the concentrations of the three asphalt fractions are 0. 54- 3.06 ×10-3 mg polars,1. 77- 9. 50 × 10-4 mg aromatics and 0. 21- 1. 23 × 10-4 mg saturates for per cubic meter air. The percentage of bitumen in airborne particles is 1. 61%-11. 02%. In the plant samples, the concentrations are 0. 29- 3.07mg polars, 0.89- 3.89 aromatics and 0. 37-1. 53 mg saturates for per gram dry plant materials.

关键词： asphalt airborne particle traffic pollution HPLC.

A Microchip Tunable Blue Laser Source Based upon Cr∶LiSAF in Contact with KN Crystal

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Chinese Journal of Lasers 2002年第1期11卷 6-9页

作者： MENG Hongxiang (dept. of Optical Engineering, Zhejiang University, Hangzhou 310027, China) HE Liangfang (dept. of Applied Physics, Zhejiang University of Technology, Hangzhou 310014, China) dept. of Optical Engineering Zhejiang University Hangzhou 310027 dept. of Applied Physics Zhejiang University ofTechnology Hangzhou 310014

In this paper, a microchip laser consisted of 2.2% doped Cr∶LiSAF crystal and NCPM KN(KNbO 3) crystal and pumped by a 679 nm laser diode is reported. The maximal output of TEM 00 4.76 mW of blue laser at 431.7 nm is obtained with the absorption power of 304.6 mW. The laser shows a threshold of 76.2 mW and slope efficiency of 2.08%. Continuous-wave tunable output is demonstrated in the blue region of 423.4～445.5 nm through only changing temperature of KN crystal controlled by PID controller.

关键词： LD pumping intracavity double Cr∶LiSAF tunable blue lasers

Oscillatory hyper Hilbert transforms along curves

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Applied Mathematics(A Journal of Chinese Universities) 2009年第3期24卷 336-342页

作者： CHEN Jie-cheng FAN Da-shan WANG Meng dept. of Math. Zhejiang University Hangzhou 310027 China dept. of Mathematical Sciences University of Wisconsin-Milwaukee Milwaukee Wisconsin 53201

The hyper Hilbert transform Tnf（x） =∫-1^1 f（x - Γ（t））e^-i｜t｜-β｜t｜^-1-αdt along an appropriate curve Γ（t） on R^n is investigated,where β 〉 α 〉 *** L^p boundedness theorem of T4 is obtained,which is... 详细信息

关键词： hyper Hilbert transform curve

Rate of strong consistency of the maximum quasi-likelihood estimator in quasi-likelihood nonlinear models

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Applied Mathematics(A Journal of Chinese Universities) 2008年第4期23卷 391-400页

作者： XIA Tian KONG Fan-chao dept. of Statist. Yunnan Univ. Kunming 650091 China dept. of Math. Anhui Univ Hefei 230039 China

Quasi-likelihood nonlinear models （QLNM） include generalized linear models as a special case. Under some regularity conditions, the rate of the strong consistency of the maximum quasi-likelihood estimation （MQLE） is obtained in QLNM. In an important case, this rate is O（n-^1/2（loglogn）^1/2）, which is just the rate of LIL of partial sums for i.i.d variables, and thus cannot be improved anymore.

关键词： maximum quasi-likelihood estimator quasi-likelihood nonlinear models strong consistency

Multilinear singular and fractional integrals on weighted Hardy spaces

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Applied Mathematics(A Journal of Chinese Universities) 2009年第2期24卷 214-220页

作者： ZHANG Pu LAN Jia-cheng dept. of Math. Mudanjiang Teachers College Mudanjiang 157012 China dept. of Math. Lishui College Lishui 323000 China

In this paper the boundedness properties of multilinear singular and fractional integrals on the weighted Hardy spaces are studied.

关键词： multilinear singular integral multilinear fractional integral Lipschitz function L^r-Dini condition weighted Hardy space

Structural Evolution of the Mn_(0.52)Sb_(0.48) Compound during High Energy Ball Milling

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Journal of Materials Science & Technology 1996年第6期12卷 434-438页

作者： Fuxing YIn and Nanju GU (dept. of Materials Science and Engineering, Hebei Institute of Technology, Tianjin 300130, China)T.Shigematsu and N.Naknishi (dept. of Chemistry, Faculty of Science, Konan University, Kobe 658, Japan)(To whom correspondence should dept. of Materials Science and Engineering Hebei Institute of Technology Tianjin 300130 China dept. of Chemistry Faculty of Science Konan University Kobe 658 Japan

The structural transitions of the NiAs-type Mn0.52Sb0.48 magneto-ordered compound, ball milled to different periods, have been characterized by X-ray diffraction and DSC analysis. On the basis of lattice parameter results a structural evolution mode with three stages is proposed. In the first stage lattice parameters keep nearly unchanged with the refinement of grains and increase of lattice strain. In the second stage, microstrain shows a lowering tendency accompanying the successive decreases of grain size. The X-ray revealed internal strain is found to be strains inside the lattice, which can be relaxed with new grain formation. The change of Tc is shown to be affected by the dimension of c axis, however the overall magnetization is continuously decreased with milling, due to the disordering process occurred in milling. Correspondent disordering mechanisms have been tentatively postulated and discussed according to the changes of lattice para meters.

关键词： Sb Ball Structural Evolution of the Mn Compound during High Energy Ball Milling

Reactive Magnetron Sputtering of CN_x Thin Films on β-Si_3N_4 Substrates

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Journal of Materials Science & Technology 1998年第3期14卷 269-272页

作者： WT.Zheng N-Hellgren and J.-E.Sundgren( dept. of Materials Science, Jilin Univer-sity Changchun 13oo23, China)(dept. of Physics, Linkoping University, S-581 83 Linkoping, Sweden) dept. of Physics Linköping University S-581 83 Linköping Sweden dept. of Materials Science Jilin University Changchun 130023 China

Carbon nitride CN. thin films have been deposited on polycrystalline β-Si3N4 substrates by un-balanced magnetron sputtering in a nitrogen discharge. Both the film deposition rate and the nitrogen concentration decrease with substrate temperature increase in the range of 100~400℃The maximum of nitrogen content is 40 at. pct. Raman spectroscopy and atomic force mi-croscopy were used to characterize the bonding, microstructure and surface roughness of the films. Nanoindentation experiments exhibit a higher hardness of 70 GPa and an extremely elas-tic recovery of 85% at higher substrate temperature.

关键词： Thin Si3N4 Substrates Reactive Magnetron Sputtering of CN_x Thin Films on CN

Application of fuzzy logic in content-based image retrieval

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Journal of Harbin Institute of Technology(New Series) 2008年第3期15卷 386-392页

作者：王小玲谢康林 dept. of Information Science Shanghai Lixin University of Commerce dept. of Computer Science and Engineering Shanghai Jiaotong University

We propose a fuzzy logic-based image retrieval system, in which the image similarity can be inferred in a nonlinear manner as human thinking. In the fuzzy inference process, weight assignments of multi-image features were resolved impliedly. Each fuzzy rule was embedded into the subjectivity of human perception of image contents. A color histogram called the average area histogram is proposed to represent the color features. Experimental results show the efficiency and feasibility of the proposed algorithms.

关键词： semantic gap fuzzy inference weight assignment subjectivity of human perception color-based image retrieval

A diffusion method based on polar coordinate for ultrasound images denoising

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Journal of Harbin Institute of Technology(New Series) 2008年第4期15卷 568-572页

作者：芦蓉沈毅 dept. of Control Science and Engineering

The paper presents a novel anisotropic diffusion approach to the problem of ultrasound images denoising based on the polar-coordinate *** gradients based on the polar coordinate are introduced and they are more suitable for ultrasound images than horizontal gradients and vertical gradients commonly used in anisotropic diffusion ***,an adaptive adjustment scheme for the threshold parameter in conduction functions is presented according to the incident angle of the ultrasonic beam with respect to the organ ***,based on the structure matrix,an edge-adaptive diffusion model is introduced,which can selectively preserve the edge from the blurring or smooth *** results of real ultrasound images show the validity of the presented approach,which takes the physical imaging mechanism of ultrasonic devices into account.

关键词： image denoising anisotropic diffusion polar coordinate ultrasound image