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^(40)Ar/^(39)Ar age evidence for Altyn fault tectonic activities in western china

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Chinese Science Bulletin 2003年第18期48卷 2024-2030页

作者： LIU Yongjiang1, J. Genser2, GE Xiaohong1, F. Neubauer2, G. Friedl2, CHANG Lihua1, REN Shoumai3 & R. Handler2 1. college of earth sciences, jilin university, changchun 13.061, china 2. Institute of Geology and Paleontology, Salzburg university, Salzburg A-5020, Austrilia 3. Statigraphic Research Center for Oil and Natural Gas, Ministry of Land and Resources, Beijing 100034, china Correspondence should be addressed to Liu Yongjiang (e-mail: liuyj@ ***) college of earth sciences Jilin University Changchun 130061 China Institute of Geology and Paleontology Salzburg University Salzburg A-5020 Austria Statigraphic Research Center for Oil and Natural Gas Ministry of Land and Resources Beijing 100034 China

Four 40Ar/39Ar age groups of mica, hornblende and K-feldspar were obtained from Proterozoic and early Paleozoic metamorphic rocks in the Aksay-Dangjin Pass area, western china. The samples away from the middle shear zone of the Altyn fault belt yield two plateau age groups in the range of 461—445.2 Ma and 414.9—342.8 Ma, respec-tively. They represent the tectono-thermal events that had been recorded in the rocks that were displaced by the Altyn strike-slip fault in late Ordovician-early Silurian and Devo-nian, respectively. These two age groups should be related to the closures of Northern and Southern Qilian Oceans. The deformed granitic gneiss from the northern belt gives a pla-teau age group of 178.4—137.5 Ma, which is interpreted as the active age of the Altyn fault in the middle-late Jurassic- early Cretaceous and should be related to the accretion of Lhasa block to the north. The sample from the middle shear zone of the Altyn fault belt yields two plateau ages of 36.4 and 26.3 Ma, respectively, suggesting the strike-slip move-ment with strong metamorphism at greenschist facies along the Altyn fault in the late Eocene. This event occurred in the most areas of the northern Tibet Plateau and should be in response in the north to the collision between Indian and Eurasian continents. The present study demonstrates that the Altyn fault is characterized by multiple pulse-style activi-ties under the tectonic setting of convergence between the Indian and Eurasian continents.

关键词： Altyn fault 40Ar/39Ar age tectono-thermal event western china

Research on the Fault Monitoring System in Free-form Surface CNC Machining Based on Wavelet Analysis

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厦门大学学报（自然科学版） 2002年第S1期41卷 72-73页

作者： XU Shu-xin 1, ZHAO Ji 2, ZHAN Jian-ming 1, LE Guan 1 (1. college of Mechanical Science and Engineering, jilin university, changchun 130022, china 2. Office of Education Administration, jilin university, changchun 130012, Chi na)

Carrying out experiments and researches on tool bre ak age and undercut of work-piece of free-form surface by using wavelet analysis, both the fault features can be extracted in a special frequency segment of wave let decompose. According to the feature of transient fault, the author proposes for the first time the automatic determination technology of the threshold by us e of the adaptive filter characteristic of wavelet transform. Based on profound researches on steady fault feature, this dissertation makes an effective token o f steady fault feature by using wavelet energy method, and proposes the new idea to identify cut-in case and cut-out case, thereby successfully gives an uniqu e description quantitatively on the characterization of the variation of fault a nd cutting condition in the monitoring system.

关键词： wavelet analysis free-form surfaces CNC mach ining monitoring system

On-line Preconcentration and Determination of Trace Metals in Water Samples by Flow Injection Combined with Flame Atomic Absorption Spectrometry via Calix[4]arene Carboxylic Acid Packed Micro-column

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Chemical Research in Chinese Universities 2012年第1期28卷 26-30页

作者： GUO Da-wang, ZHAO Xiao-wei, JIA Qiong and ZHOU Wei-hong college of Chemistry, jilin university, changchun 130012, P. R. china college of Chemistry Jilin University Changchun 130012

An adsorbent calix[4]arene carboxylic acid was employed as the adsorption material for on-line flow in jection（FI） micro-column preconcentration coupled with flame atomic absorption spectrometry（FAAS） determination of trace heavy metals（Cu, Pb, Co, Ni and Cd）. Parameters such as the pH, loading time and flow rate of sample, and the concentration, volume and flow rate of eluent were optimized. The enrichment factors are 50.0, 56.5, 11.6, 12.1 and 19.1 for Cu, Pb, Co, Ni, and Cd, respectively, and a sample throughput of 20 h–1 was obtained. The limits of de tection for Cu, Pb, Co, Ni, and Cd were in a range of 1.56―3.91 μg/L, and the relative standard deviations（RSDs） were less than 2.76%（n=7）. Furthermore, the proposed method was successfully applied to the determination of Cu, Pb, Co, Ni, and Cd in certified reference materials and various water samples.

关键词： Calixarene carboxylic acid Preconcentration Flow injection Metal ion Flame atomic absorptionspectrometry(FAAS)

The microbial metallogeny of weathering crust REE deposits in South china

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Chinese Science Bulletin 1999年第S2期44卷 71-73页

作者： CHEN Binghui~(1,2), WANG Zhimei~3, HUANG Limei~3, WU Fuhai~3, CHEN Jingde~2 and XU Wenlie~2 1. Department of earth sciences, Nanjing university, Nanjing 210093, china 2. Department of earth sciences, Zhongshan university, Guangzhou 510275, china 3. Guangdong Pharmaceutical college, Guangzhou 510244, china Department of earth sciences Nanjing University Nanjing 210093 China Department of earth sciences Zhongshan University Guangzhou 510275 China Guangdong Pharmaceutical college Guangzhou 510244 China

VERY little is known about the roles of microorganisms in the metallogeny of weathering crust REE deposits, although there has been much literature on REE behavior in weathering conditions. The present note deals with the microorganisms in 4 weathering profiles of an REE deposit and their roles in migration and accumulation of REE in weathering conditions. 1 Cultivation and identification of microorganisms Under strict sterilization, samples were collected from various parts of 4 weathering profiles of granites in a weathering crust REE deposit in South china. The samples were then cultivated for microorganisms with ordinary agars as culture media and then the cultivated microorganisms were dyed and identifiedunder a microscope. The sampled positions and cultivated numbers of microbial colonies are shown

关键词： microbial metallogeny weathering crust REE deposit South china.

URBANIZATION AND ITS IMPACTS ON WATER ENVIRONMENT IN TUMEN RIVER BASIN

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Chinese Geographical Science 2002年第3期12卷 273-281页

作者： WANG Shi-jun,WANG Dan,YANG Xiang-h ua(college of Urban and Environmental sciences,Northeast Normal university,changchun 130024,P.R.china) college of Urban and Environmental sciences Northeast Normal University Changchun P. R. China

The trans-boundary scope of the Tume n River Basin(TRB)going through china,Russia and DPRK has been defined,and on the basis of this,status of urbanization and its impacts on water environment in recent 20years in TRB have been *** n in TRB can be characterized as:1)There is medium level of overall urbanization in *** distance still exists compared with developed *** it is lower than the average urbanization level of Russia and higher than that o f china.2)There is unbalanced distribution of urbanization development in *** in china part owns the c haracter of low starting point and hi gh-speed *** Russia part,charac-ter of urbanization can be described as high starting point and stable *** DPRK part,urbanizatio n level is low,and motive power lacks.3)Due to large population,in china part there is broader region urbanized,larger radius and higher frequency of human activities,which lead to heavier pressure on ***,the paper has point-ed that impacts of urbanization on wa ter environment are as follows:1)Urban population growth and industr y develop-ment increase the demand for freshwa ter,and also exacerbate the contrad iction between limited water supply and increas-ing freshwater demand.2)Urban infrastructure doesn’t match with urban productive function especially treatment facili-ties,which results in the pollution of the Tumen River.3)The pollution situation in the Tumen River got peak point in1995,and presently,such situation has been improved in great scale,due to effective interventions ***,there still exist 2enterprises that are urgent to be ***,pollution of municipal sewage will become more and more apparent.4)The influence of urbanization on soil is mainly caused by industrial effl uent and slag,and pollut-ed water *** and water l oss has also been a serious problem caused by urbanization.5)Urbanization results in the decrease of wet

关键词： tumen river basin (TRB) urbanization water environment

Structures and stability of isomers of[Si,N,N,P]system

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Science china Chemistry 2004年第2期47卷 98-105页

作者： KAN Wei1, YU Haitao1, LI Mingxia1, FU Honggang1,2 & SUN Jiazhong1,2 1. college of Chemistry and Chemical Engineering, Heilongjiang university, Harbin 150080, china 2. State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, jilin university, changchun 130023, china college of Chemistry and Chemical Engineering Heilongjiang University Harbin China State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun China

Some stationary points on the potential energy surface of [Si, N, N, P] system were located at the B3LYP/6-311G(d) and QCISD(t)/6-311+G(2df)(single-point) levels of theory, while the isomerization, structures, and stability of these obtained isomers were suggested. The computed results indicate that only four-membered ring isomer SiNPN(E1, 2A'), which possesses butterfly-like structure and Si-P cross bonding, is kinetically stable in all optimized isomers. Other isomers may be considered as kinetically unstable towards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, the present paper also proposes electronic and geometric structures, vibrational frequencies and the corresponding vibrational modes, dipole moments, and rotational constants of isomer E1. To make use of the computed results, we can clearly know that the reaction pathway via an intermediate E3 (SiNPN) is the most favorable channel producing isomer E1 from fragments SiN(2Π) and PN (1Σ), which have been well characterized in space, and thus, isomer E1 can be considered as a candidate for interstellar observation. The reaction enthalpy of SiN(2Π) + PN(1Σ)→ E1 and the standard enthalpy of formation of isomer E1 are 215.25 and 457.99 kJ/mol, respectively, at 298.15 K. Keywords potential energy surface - [Si,N,N,P] system - isomerization - kinetic stability

关键词： potential energy surface, [Si,N,N,P] system, isomerization, kinetic stability.

Nonlinear analysis on the coupling process of electromagnetic vibrator and earth

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Science china earth sciences 2005年第8期48卷 1175-1182页

作者： CHEN Zubin1,2, TENG Jiwen2, LIN Jun1, ZHANG Linhang1 & JIANG Zhongjin1 1. Institute of Intelligent Instrument & Measurement Control Technology, jilin university, changchun 130026, china 2. Institute of Geology & Geophysics, Chinese Academy of sciences, Beijing 100029, china Institute of Intelligent Instrument & Measurement Control Technology Jilin University Changchun China Institute of Geology & Geophysics Chinese Academy of Sciences Beijing China

The linear model based on the hydraulic pressure vibrator has been no longer adaptable to the electromagnetic vibrator. In order to realize the effective transmission of the limited energy from the vibrator to the ground, it is important to study the coupling model of the electromagnetic vibrator and the earth. In this paper, a nonlinear restore term was introduced to the coupling model because of the existence of a large amount of harmonics in the vibrator baseplate. The nonlinear vibration analysis was applied to the model by the multiscale method. In the course of energy transmission from the vibrator to the ground, ultraharmonic resonance was used to explain the generation of harmonics. An improved scheme was advanced to select the cross correlation reference signal in the vibrator seismic exploration. Good application results were obtained in field experiments.

关键词： vibrator, coupling model, electromagnetic, nonlinear vibration.

Geochemical research on C-O and Sr-Nd isotopes of mantle-derived rocks from Shandong Province, china

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Science china earth sciences 2004年第2期47卷 171-180页

作者： LIU Jianming, ZHANG Hongfu, SUN Jinggui & YE Jie1. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100029, china 2. School of earth Science, jilin university, changchun 13.061, china Correspondence should be addressed to Liu Jianming (email: jmliu@***) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China School of earth Science Jilin University Changchun China

This paper presents systematic studies on the C-O and Sr-Nd isotopic compositions for Cretaceous Badou carbonatites, Fangcheng basalts, and Jiaodong lamprophyres and Paleozoic Mengyin kimberlites in Shandong Province, china. Paleozoic kimberlites have normal and uniform C-O isotopic compositions with δ13C and δ18O in the range of -4.8‰--7.6‰ and +9.9‰-+13.2‰, respectively. However, Cretaceous three different types of mantle-derived rocks have quite different C-O isotopic compositions, indicating that the mantle sources are probably partially contaminated with organic carbon-bearing crustal materials. These Cretaceous rocks show uniform and EMII-like Sr-Nd isotopic compositions and also indicate that the mantle sources were affected by recycled crustal materials. Comparative studies of C-O and Sr-Nd isotopes reveal that the lithospheric mantle beneath the eastern North china Craton had different isotope characteristics in the Paleozoic, the early Cretaceous, and the Tertiary time. This demonstrates that the lithospheric mantle beneath the region underwent at least twice reconstructions since the Paleozoic. Available data imply that the first reconstruction mainly happened during the Triassic-Jurassic time with gradual changes and the second in the Cretaceous with abrupt changes. Results also show that the early Cretaceous (especially at 120-130 Ma) was perhaps the key period leading to the dramatic change of the Mesozoic geodynamics on the eastern North china Craton.

关键词： mantle-derived rocks, carbonate minerals, C-O isotope, Sr-Nd isotope, lithospheric mantle, Shandong.

Contribution of Root and Microbial Respiration to Soil CO_2 Efflux and Their Environmental Controls in a Humid Temperate Grassland of Japan

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Pedosphere 2009年第1期19卷 31-39页

作者： WANG Wei FENG Jiang T. OIKAWA Department of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 （China） School of Urban and Environmental sciences Northeast Normal University Changchun 130024 （China） Institute of Biological sciences University of Tsukuba Tsukuba Ibaraki 305-8572 （Japan）

Soil CO2 efflux, root mass, and root production were investigated in a humid temperate grassland of Japan over a growing season （Apr. to Sep.） of 2005 to reveal seasonal changes of soil CO2 efflux, to separate the respective contributions of root and microbial respiration to the total soil CO2 efttux, and to determine the environmental factors that control soil respiration. Minimal microbial respiration rate was estimated based on the linear regression equations between soil CO2 effiux and root mass at different experimental sites. Soil CO2 efflux, ranging from 4.99 to 16.29 μmol CO2 m^-2 s^-1, depended on the seasonal changes in soil temperature. The root mass at 0-10 cm soil depth was 0.82 and 1.27 kg m^-2 in Apr. and Sep., respectively. The root mass at 0-10 cm soil depth comprised 60% of the total root mass at 0-50 cm soil depth. The root productivity at 0-30 cm depth varied from 8 to 180 g m^-2 month^-1. Microbial and root respiration rates ranged from 1.35 to 5.51 and 2.72 to 12.06μmol CO2 m^-2 s^-1, respectively. The contribution of root respiration to the total soil CO2 efflux averaged 53%, ranging from 33% to 72%. The microbial respiration rate was exponentially related to soil temperature at 10 cm depth （R^2 = 0.9400, P = 0.002, n = 6）, and the root respiration rate was linearly related to the root production at 0-30 cm depth （R2 = 0.6561, P = 0.042, n = 6）.

关键词： grasslands microbial respiration root production root respiration