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Urine products of bone breakdown as markers of bone resorption and clinical usefulness of urinary hydroxyproline:an overview

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Chinese Medical Journal 2004年第2期17卷 291-295页

作者： Baris Simsek zgülKaracaer inci Karaca Department of Oral and Maxillofacial Surgery Faculty of Dentistry University of Gazi Emek Ankara TurkeyDepartment of Oral and Maxillofacial Surgery Faculty of Dentistry University of Gazi Emek Ankara TurkeyDepartment of Prosthodontics Faculty of Dentistry University of Gazi Emek Ankara Turkey

Purpose The purpose of this study is to review the urine products of bone breakdown as markers of bone resorption and usefulness of urinary hydroxyproline.Data Related researches published in 1985 -2000 were systematically reviewed.Results Bone markers could be used for early diagnosis of bone metabolic diseases. Biochemical markers of bone resorption that reflect osteoclast activity and/or collagen degradation provide a new and potentially important clinical tool for the assessment and monitoring of bone metabolism. Assessment of bone resorption can be achieved with measurement of urinary hydroxylysine glycosides, urinary excretion of the collagen pyridinium cross-links, urinary excretion of type I collagen telopeptide breakdown products (cross-linked telopeptides) and urinary hydroxyproline.Conclusion Urinary hydroxyproline has been in use as a marker of bone resorption, but it lacks sensitivity and specificity. It is a modified aminoacid that is a metabolic product of collagen breakdown. Hydroxyproline may be released either free or with fragments of the collagen molecule attached during bone resorption, and it is also liberated by the breakdown of complement and nonskeletal collagen.

关键词： bone resorption marker biochemical markers hydroxyproline collagen breakdown hydroxylysine glycosides pyrolidine deoxypyrolidine N-tebpeptides C-telopeptides

Cyclic Saturation Dislocation Pattern Observation in the Vicinity of Grain Boundaries by Electron Channeling Contrast Technique

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Journal of Materials Science & Technology 1998年第3期14卷 211-214页

作者： Zhang, ZF Li, XW Su, HH Wang, zg Acad Sinica Inst Met Res State Key Lab Fatigue & Fracture Mat Shenyang 110015 Peoples R China

The cyclic saturation dislocation patterns within grains and in the vicinity of low-angle grain boundaries in fatigued copper crystal were successfully observed by electron channeling contrast technique in SEM. The results show that the dislocation patterns within grains consisted of typical two-phase structure, i.e. persistent slip bands (PSB) and veins. With increasing plastic strain amplitude (gamma(pl) greater than or equal to 1.7 x 10(-3)), large amount of PSBs and regular dislocation walls were observed. The dislocation walls and PSBs could cross through the low-angle grain boundaries continuously except that the dislocation-free zone (DFZs) appeared at some local regions. Combining with the cyclic stress-strain response and dislocation patterns, the effect of low-angle grain boundaries on cyclic deformation behavior was discussed.

关键词： Copper

PROOF OF A CONJECTURE RELATED TO THE PARABOLIC CLASS NUMBERS OF SOME FUCHSIAN GROUPS

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Acta Mathematica Scientia 2005年第2期25卷 215-222页

作者： Nihal Yilmazzgür Refik Keskin Department of Mathematics Faculty of Art and Sciences Balikesir University110100 BalikesirTurkeyDepartment of Mathematics Faculty of Art and SciencesSakarya UniversitySakaryaTurkey

This paper proves a conjecture given in [6], which is concerning with the parabolic class numbers of some Fuchsian groups.

关键词： Parabolic class number. Fuchsian group discrete group

Brief Review and Reconsideration of Fatigue Crack Closure Effect in Materials

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Journal of Materials Science & Technology 1997年第1期13卷 1-14页

作者： Chen, DL Weiss, B Stickler, R Wang, zg ACAD SINICA INST MET RESSTATE KEY LAB FATIGUE & FRACTURE MATSHENYANG 110015PEOPLES R CHINA UNIV VIENNA INST PHYS CHEM MAT SCIA-1090 VIENNAAUSTRIA

The state-of-the-art of fatigue crack closure effect, involving the mechanisms, measurements, models, evaluation methods, influencing factors and existing problems is briefly reviewed. Attention is concentrated on a new consideration of closure effect and a re-definition of the effective driving force for the propagation of a fatigue crack. A theoretical basis for measuring the closure effect is established. The proposed closure concept takes into account the role of the tower portion of loading cycle below the opening load. The conventional closure concept is proven to be correct only for some extreme cases which are practically non-existent for engineering materials. A miniature strain gauge technique is developed to measure the crack closure. Stress-ratio-change tests at threshold level clearly indicate the shortcomings of the conventional closure concept, and the validity of the newly-proposed closure concept. The application of the proposed concept can give rise to a new method for the determination of the effective fatigue threshold of materials. If the fatigue threshold is measured at a sufficiently negative stress ratio (R

关键词： STP Brief Review and Reconsideration of Fatigue Crack Closure Effect in Materials ASTM

Photoluminescence of ZnS Clusters in Zeolite-Y

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Journal of Materials Science & Technology 1997年第5期13卷 397-404页

作者： Chen, W Wang, zg Lin, ZJ Xu, Y Lin, LY Lab. of Semiconductor Materials Sciences Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

Two obvious emissions are observed from the ZnS clusters encapsulated in zeolite-Y. The emission around 355 nm is sharp and weak, locating at the onset of the absorption edge. The band around 535 nm is broad, strong and Stokes-shifted. Both the two emissions shift to blue and their intensities firstly increase then decrease as the loading of ZnS in zeolite-Y or clusters size decreases. Through investigation, the former is attributed to the excitonic fluorescence, and the latter to the trapped luminescence from surface states. The cluster size-dependence of the luminescence may be explained qualitatively by considering both the carrier recombination and the nonradiative recombination rates. Four peaks appearing in the excitation spectra are assigned to the transitions of 1S-1S, 1S-1P, 1S-1D and surface state, respectively. The excitation spectra of the clusters do not coincide with their absorption spectra. The states splitted by quantum-size confinement are detected in the excitation spectra, but could not be differentiated in the optical absorption spectra due to inhomogeneous broadening. The size-dependence of the excitation spectra is similar to that of the absorption spectra. Both the excitation spectra of excitonic and of trapped emissions are similar, but change in relative intensity and shift in position are observed.

关键词： Zeolites

Development and actualization of brownfields database with the use of unmanned aerial vehicles-the case of Upper Silesia,Poland

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International Journal of Coal Science & Technology 2022年第6期9卷 168-177页

作者： Aleksandra zgórska Adam Hamerla Jan Bondaruk Pawel Zawartka Department of Water Protection Central Mining InstitutePlac Gwarków 144-166 KatowicePoland Deputy Director for Environmental Engineering Central Mining Institute Plac Gwarkow 144-166 KatowicePoland

This paper presents the assumptions and the preliminary results of the project entitled"Extension of the system for man-agement of post-mining areas in the Silesian province-OPI TPP 2.0".The overall objective of the project is to develop and implement a new e-service in the form of an open-access information system on post-mining areas in the Silesia *** range of information and tools planned to be made available is dedicated to assessing the possibilities and potential for economic and social reuse of these *** basic and extremely important stage of the project was to identify and collect data on post-industrial sites located in the Silesia *** information contained in this article illustrates the activities that were carried out in the initial phase of the project in which unmanned aerial vehicles(UAV)were used to identify and acquire information on brownfields(including post-mining sites)entered into the developed common *** article assesses the possibility of using drones in an enterprise of such a large scale and also points out the advantages of using this *** article describes the methodology and scope of work related to the acquisition of data that can be collected using unmanned aerial vehicle(UAV)covering surface infrastructure and land use of brownfields,allowing for the identification of negative phenomena on their site as well as monitoring of naturally occurring *** on fieldworks experience and the results of numerous analyses carried out for different types of brownfields(***-mining areas,former transport bases,settling ponds,etc.),paper presents the advantages and benefits of drones(UAN)over other data sources used to monitor changes in an *** article is based on the results of an inventory of over 600 brownfields located in Upper Silesia region(Silesia Voivodeship,Poland).

关键词： Unmanned aerial vehicle Brownfields Post-industrial sites Databases Drones

Cyclic Deformation and Fatigue Damage Behavior of Cu Monocrystals, Bicrystals and Tricrystals

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Journal of Materials Science & Technology 1999年第6期15卷 489-508页

作者： Wang, zg Li, XW Zhang, ZF Jia, WP Li, SX Chinese Acad Sci Inst Met Res State Key Lab Fatigue & Fracture Mat Shenyang 110015 Peoples R China

In the present work, the cyclic deformation behavior of Cu single crystals oriented for double- and multiple slip as well as Cu bicrystals and tricrystals was investigated under constant plastic strain control at room temperature in air. The main objectives of the study are: (1) to find out the effects of crystallographic orientation and grain boundary (GB) on the cyclic stress-strain (CSS) curves; (2) to compare the cyclic deformation behavior of the double-, multiple-slip crystals, bicrystals and tricrystals with that of single-slip oriented crystals and to correlate the results with those of polycrystals; (3) to examine the corresponding dislocation structures; (4) to investigate the interactions of persistent slip bands (PSBs) with GBs and triple joint (TJ) as well as intergranular fatigue cracking in Cu bicrystals and tricrystals.

关键词： Crystals

STM Study on the Surface Relief and Mechanism of Bainite Transformation

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Journal of Materials Science & Technology 1996年第4期12卷 249-254页

作者： Yang, zg Fang, HS Wang, JJ Zheng, YK Li, CM Dept. of Materials Science and Engineering Tsinghua University Beijing 100084 China

Scanning tunneling microscopy (STM) has been first employed to study the surface relief accompanying bainite transformation in a Fe-2.17C-12.18Cr-0.31Si-0.26Mn (wt pct) steel. With the exclusive vertical resolution of STM, we observed that the surface relief associated with bainite is a group of surface reliefs related to subplates, subunits and sub-subunits. As a whole, the relief group is in a tent shape, not of invariant plane strain (IPS) type, which is obviously different from that of martensite, and implying that bainite is not formed by shear mechanism. The fine structure of bainite in Fe-1.0C-4Cr-2.0Si (wt pct) alloy has also been studied with STM and TEM. It is found that the bainite plate is composed of subplates, subunits and sub-subunits. On the basis of the fine structure inside a bainitic ferrite plate observed under STM, a sympathetic-ledgewise mechanism of bainite formation is proposed.

关键词： Steel

Determination of global mean sea surface WHU2000 using multi-satellite altimetric data

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Chinese Science Bulletin 2002年第19期47卷 1664-1668页

作者： Jiang, WP Li, JC Wang, zg Wuhan Univ Sch Geodesy & Geophys Wuhan 430079 Peoples R China

In this study, the overall editing criteria for altimetric data are considered and the geophysical correction models is improved. The datum for various altimetric data is also unified and the method of a full-combined crossover adjustment for different altimetric tracks is used to improve the radial orbits of Geosat, ERS-1 and ERS-2 data. In addition, the method for determining mean sea surface (MSS) by using multi-altimetric data is developed. The data used to compute WHU2000 MSS include 7-year Topex/Poseidon data (cycles 11-249), 2-year Geosat ERM data (cycles 1-44), 5-year ERS2 data (cycles 1-52) and all ERS-1 168-day data. The WHU2000 MSS is determined with a grid resolution of 2’×2’ within the ± 82° latitude and its precision is better than 0.05 m. Comparing WHU 2000MSS with 3.75’×3.75’ CLS_SHOM98.2 MSS, 3’×3’ GFZ MSS95A and 3.75’×3.75’ OSU MSS95, as external checks, the corresponding standard deviation (STD) of their differences is 0.090 m, 0.211 m and 0.079 m respectively.

关键词： altimetry mean sea surface crossover adjustment.