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^(13)C NMR spectra of tectonic coals and the effects of stress on structural components

Science china Earth sciences 2005年第9期48卷 1418-1437页

作者： JU Yiwen1,2, JIANG Bo1, HOU Quanlin2, WANG Guiliang1 & NI Shanqin2 1. College of Mineral Resource and geosciences, china university of Mining and technology, Xuzhou 221008, china 2. Laboratory of Computational Geodynamics, College of geosciences, Graduate School of Chinese Academy of sciences, beijing 100049, china College of Mineral Resource and geosciences China University of Mining and Technology Xuzhou China Laboratory of Computational Geodynamics College of Geosciences Graduate School of Chinese Academy of Sciences Beijing China

High-resolution 13C Nuclear Magnetic Resonance (NMR) spectra of different kinds of tectonic coals were obtained using the NMR (CP/MAS+TOSS) method. On the basis of this, after simulation synthesis and division of spectra, the relative contents of carbon functional groups were calculated. Combined with results of Ro, max, XRD testing and element analysis, stress effects on the composition of macromolecular structures in tectonic coals were studied further. The results showed that Ro, max was not only the important index for describing coal rank, but was also effective for estimating the stress effect of tectonic coals. Under tectonic stress ac- tion, Ro, max was the most direct indicator of the coal structure and chemical components. Changes in the stacking Lc of the coal basic structure unit (BSU) and La/Lc parameters could distinguish the temperature and stress effects on metamorphic-deformed environments, and re- flected the degree of structural deformation. Therefore, on the whole, Lc and La/Lc can be used to index of the degree of structural deformation of tectonic coals. In different metamorphic and de- formed environments, different kinds of tectonic coals are formed under structural stress. The changes in characteristics of the macromolecular structure and chemical composition are such that as the increase in structural deformation becomes stronger, from the brittle deformation coal to ductile deformation coal, the ratio of width at the half height of the aromatic carbon and ali- phatic carbon peaks (Hfa/Hfal ) was increased. As carbon aromaticity was raised further, carbon aliphaticity reduced obviously and different compositions of macromolecular structure appeared as a jump and wave pattern except for in wrinkle structure coal, which might result chiefly from stress effects on the macromolecular structure of different kinds of tectonic coals. The macro- moecular changes of wrinkle structure coal are reflected mainly on physical structure. In the metamorphi

关键词： tectonic coal, NMR, macromolecular structure, chemical component, stress effect.

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Scan chain design for shift power reduction in scan-based testing

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Science china(Information sciences) 2011年第4期54卷 767-777页

作者： LI Jia 1,HU Yu 2 & LI XiaoWei 2 1 The School of Software,Tsinghua university,beijing 100084,china 2 The Institute of Computing technology,Chinese Academy of sciences,beijing 100190,china The School of Software Tsinghua University Beijing China The Institute of Computing technology Chinese Academy of Sciences Beijing China

Test power of VLSI systems has become a challenging issue *** scan shift power dominates the average test power and restricts clock frequency of the shift phase,leading to excessive thermal accumulation and long test *** paper proposes a scan chain design technique to solve the above *** on weighted transition metric (WTM),the proposed extended WTM (EWTM) that is utilized to guide the scan chain design algorithm can estimate the scan shift power in both the shift-in and shift-out ***,the wire length overhead of the proposed scan chain design can also be reduced by the proposed distance of EWTM (DEWTM) *** results confirm that the proposed approach can significantly reduce scan shift power with low wire length overhead.

关键词： low power DfT scan-based testing test power reduction scan chain design

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Implications of micro-compositions of garnet and biotite from high-grade meta-pelites

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Progress in Natural Science:materials International 2006年第2期16卷 209-214页

作者： ZHOU Xiwen, WEI Chunjing, and ZHANG Shangkun ( Institute of Geology, CAGS, beijing 100037, china School of Earth and Space sciences, Peking university, beijing 100871, china china university of Geo-sciences, beijing 100083, china) Institute of Geology CAGS Beijing 100037 China School of Earth and Space sciences Peking University Beijing 100871 China china university of Geo-sciences Beijing 100083 China

Based on detailed studies on the compositional zoning of garnet and biotite in pelitic rocks from the Jingshan group of granulite facies in north Jiaodong, P-T pseudosections with isopleths of Fe/(Fe + Mg) in garnet and biotite were calculated in the KF-MASH system for two representative rocks of sillimanite-garnet-cordierite-biotite gneiss ( Vbi/ Vg>1 ) and sillimanite-garnet gneiss (Vbi/ Vg2) using the software THERMOCALC and the internally consistent thermodynamic dataset. With a comparison of the calculated Fe/(Fe+ Mg) values in garnet and biotite in the peak P-T fields constrained by peak mineral assemblages with the measured ones, it is concluded that the coarse garnet crystals with diffusion zoning from high grade meta-pelites can preserve their peak compositions even when they have experienced a cooling event, and that biotite crystals surrounded by fetsic minerals in biotite-rich rocks with Vbi/Vg> 1 can nearly preserve their peak compositions, and biotites in garnet-rich rocks with Vbi/Vg2 cannot preserve their peak compositions due to the influence of grain-boundary fluid.

关键词： high-grade meta-pelites THERMOCALC P-T pseudosection peak compositions of garnet and biotite.

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Threshold proxy quantum signature scheme with threshold shared verification

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Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 1079-1088页

作者： YANG YuGuang1,3,4 & WEN QiaoYan2 1 College of Computer Science and technology,beijing university of technology,beijing 100124,china 2 State Key Laboratory of Networking and Switching technology,beijing university of Posts and Tele-communications,beijing 100876,china 3 State Key Laboratory of Integrated Services Network,Xidian university,Xi’an 710071,china 4 State Key Laboratory of Information Security(Graduate university of Chinese Academy of sciences) ,beijing 100049,china College of Computer Science and technology Beijing University of Technology Beijing China State Key Laboratory of Integrated Services Network Xidian University Xi’an China State Key Laboratory of Information Security (Graduate university of Chinese Academy of sciences) Beijing China State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications Beijing China

A threshold proxy quantum signature scheme with threshold shared verification is proposed. An original signer could authorize a group as its proxy signers. Then only t or more of n persons in the proxy group can generate the proxy signature on behalf of the original signer and any t-1 or fewer ones cannot do that. When the proxy signature needs to be verified,any t or more of n persons belonging to the verification group can verify the message and any t-1 or fewer ones cannot verify the validity of the proxy signature.

关键词： quantum signature threshold proxy quantum group signature threshold shared verification

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SOME PROPERTIES OF LSQR FOR LARGE SPARSE LINEAR LEAST SQUARES PROBLEMS

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Journal of Systems Science & Complexity 2010年第4期23卷 815-821页

作者： Zhongxiao JIA Department of Mathematical sciences,Tsinghua university,beijing 100084,china. Department of Mathematical sciences Tsinghua University Beijing China

It is well-known that many Krylov solvers for linear systems,eigenvalue problems,andsingular value decomposition problems have very simple and elegant formulas for residual *** not only allow us to further understand the methods theoretically but also can be usedas cheap stopping criteria without forming approximate solutions and residuals at each step beforeconvergence takes *** for large sparse linear least squares problems is based on the Lanczosbidiagonalization process and is a Krylov ***,there has not yet been an analogouslyelegant formula for residual *** paper derives such kind of *** addition,the authorgets some other properties of LSQR and its mathematically equivalent CGLS.

关键词： CGLS krylov subspace lanczos bidiagonalization least squares lsqr normal equations.

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Threshold quantum secret sharing between multi-party and multi-party

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Science china(Physics,Mechanics & Astronomy) 2008年第9期51卷 1308-1315页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4 1 College of Computer Science and technology,beijing university of technology,beijing 100124,china 2 State Key Laboratory of Integrated Services Network,Xidian university,Xi’an 710071,china 3 State Key Laboratory of Information Security (Graduate university of Chinese Academy of sciences),beijing 100049,china 4 State Key Laboratory of Networking and Switching technology,beijing university of Posts and Tele-communications,beijing 100876,china College of Computer Science and technology Beijing University of Technology Beijing China State Key Laboratory of Integrated Services Network Xidian University Xi’an China State Key Laboratory of Information Security (Graduate university of Chinese Academy of sciences) Beijing China State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications Beijing China

A threshold quantum secret sharing (TQSS) scheme between multi-party and multi-party was proposed using a sequence of single photons,which is useful and efficient when the parties of communication are not all present. We described the process of this TQSS scheme and discussed its security. It was shown that entan-glement is not necessary for quantum secret sharing. Moreover,the theoretic effi-ciency was improved to approach 100% as almost all the instances can be used for generating the private key,and each photon can carry one bit of information. This protocol is feasible with the present-day technique.

关键词： threshold quantum secret sharing quantum cryptography single photon multi-party and multi-party

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Cleaning of Chromate Manufacture Process

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International Journal of Minerals,Metallurgy and materials 2000年第2期14卷 132-134页

作者： Xing Zou Yi Zhang(Applied Science School, university of Science and technology beijing, beijing 100083, china)(Institute of Engineering Chemistry and Metallurgy, Chinese Academy of sciences, beijing 100080, china) Applied Science School University of Science and Technology Beijing Beijing 100083 China Institute of Engineering Chemistry and Metallurgy Chinese Academy of Sciences Beijing 100080 China

Sodium chromate solubility is determined in the range of NaOH concentrations from 450 to 810 g/L andsolution temperatUres from 30 to 110℃. The optimized conditions to separate sodium chromate from NaOH inleached solution are resolved. It is first found the method to efficiently separate sbdium chromate from NaOH andsodium altuninate in crude sodium chromate. Bench-scale studies on the separating are performed. Finally, goodseparation results are achieved.

关键词： chromate separation clean process

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Entropy number and non-linear approximations on multivariate Besov space by manifolds of finite pseudo-dimension

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Progress in Natural Science:materials International 2006年第3期16卷 260-265页

作者： LONG Jingfan and FANG Gensun (School of Mathematical sciences, beijing Normal university, beijing 100875, china Department of Computer Science, Information technology Institute, beijing 100101, china) School of Mathematical sciences Beijing Normal University Beijing 100875 China Department of Computer Science Information Technology Institute Beijing 100101 China

We determine the asymptotic order of entropy number and optimal non -linear approximations of anisotropic periodic Besov class of Bpθr(Td') (1≤p≤∞,1≤0≤∞) by manifolds of finite pseudo-dimension in the metric Lq... 详细信息

关键词： Pseudo-dimension anisotropic Besov class of functions entropy number nonlinear width.

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Development and application of ergodicity model with FRCM and FLAR for hydrological process

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Science china(Technological sciences) 2009年第2期52卷 379-386页

作者： WANG HongRui1, FENG QiLei2, LIN Xin3 & ZENG WenYi4 1 College of Water Science, Key Laboratory for Water and Sediment sciences of the Ministry of Education, beijing Normal university, beijing 100875, china 2 School of Science, beijing Institute of Education, beijing 100011, china 3 School of Mathematical sciences, beijing Normal university, beijing 100875, china 4 College of Information Science and technology, beijing Normal university, beijing 100875, china College of Water Science Key Laboratory for Water and Sediment Sciences of the Ministry of Education Beijing Normal University Beijing China School of Science Beijing Institute of Education Beijing China School of Mathematical sciences Beijing Normal University Beijing China College of Information Science and technology Beijing Normal University Beijing China

In this paper, a new ergodic property analysis model of hydrological process is proposed based on fuzzy-rough c-means clustering (FRCM), autocorrelogram, and fuzzy least absolute regression (FLAR). A precipitation time series (1951―2004) from Shanghai Hydrology Station is then analyzed with the model. The results show that the precipitation time series of April, May, June, and September has er-godic property. We conclude that in the long run, the precipitation of April, May, June, and September will not keep decreasing; it will converge to its mean value in some period.

关键词： hydrological process ergodic autocorrelogram fuzzy-rough c-means clustering fuzzy least absolute regression

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Lithosphere types in North china:Evidence from geology and geophysics

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Science china Earth sciences 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2, DENG Jinfu3, ZHOU Su3, LI Jinfa4, XIAO Qinghui1,5, WU Zongxu6 & LIU Cui3 1. Institute of Geology, Chinese Academy of Geological sciences, beijing 100037, china 2. Development and Research Center, china Geological Survey, beijing 100037, china 3. china university of geosciences, beijing 100083, china 4. china university of geosciences, Wuhan 430074, china 5. Information Center of Ministry of Land and Resources, beijing 100812, china 6. Institute of Geology, State Seismological Bureau, beijing 100029, china Institute of Geology Chinese Academy of Geological Sciences Beijing China Development and Research Center China Geological Survey Beijing China china university of geosciences Beijing China china university of geosciences Wuhan China Information Center of Ministry of Land and Resources Beijing China Institute of Geology State Seismological Bureau Beijing China

On the basis of the characteristics of geology and geophysics in North china, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North china platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North china Platform is a remnant of cratonic lithosphere after the North china platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North china craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North china platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North china in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process

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