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science china Chemistry 2004年第6期47卷 466-479页

作者： SONG Huajie1,2. XIAO Heming1 & DONG Haishan2.1. department of Chemistry, nanjing university of {2. and Technology, nanjing 2.0094, china 2. Institute of Chemical Materials, china Academy of Engineering Physics, Mianyang 62.900, china 1. department of Chemistry Nanjing University of Science and Technology 210094 Nanjing China 2. Institute of Chemical Materials China Academy of Engineering Physics 621900 Mianyang China

The symmetry-adapted perturbation theory (SAPT) that has the ability in decompo- sition of the total interaction energy into physically meaningful components is used to provide a more fundamental understanding of intermolecular forces. This work was motivated by the diffi- culty of standard SAPT in computing the intermolecular interactions for large energetic dimer systems. SAPT based on Kohn-Sham orbitals (SAPT(DFT)) proves computationally efficient for these large systems, but has been shown to perform poorly for interaction energy components. The deficiencies of SAPT(DFT) result from wrong asymptotical behaviors of commonly used exchange-correlation potentials. To remove the deficiencies, two asymptotic corrections by means of van Leeuwen and Baerends (LB) model potential and Fermi-Amaldi (FA) type potential were applied into three small test systems comprising He2. HF2.and (N2.2.and a set of larger ni- tramide dimers at several separations. The results showed that when utilizing newly developed frequency-dependent density susceptibilities (FDDS) technique for computing dispersion energy, the FA asymptotic correction is very effective to circumvent these deficiencies in SAPT(DFT) and yields a good accuracy over the LB correction. The FA corrected SAPT(DFT) approach is capa- ble of correctly predicting all the quantitative trends in binding energies for all test cases and substantially reduces computational cost as compared with the standard SAPT calculations. The successful application of the approach to nitramide dimer demonstrates that it potentially pro- vides a good means to calculate accurately intermolecular forces in larger system such as en- ergetic systems.

关键词： intermolecular interaction, density functional theory (DFT), symmetry adapted perturbation theory (SAPT), asymptotic correction, frequency-dependent density susceptibilities (FDDS).

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LIMIT CYCLES AND BIFURCATION CURVES FOR THE QUADRATIC DIFFERENTIAL SYSTEM (III)_(m=0) HAVING THREE ANTI-SADDLES (I)

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Chinese Annals of Mathematics,Series B 1996年第2期17卷 167-174页

作者： YE YANQIAN department of Mathematics, nanjing university, {2. 2.0008, china. 南京大学数学系江苏南京

For the quadratic system: x=-y+δx + lx2.+ ny2. y=x(1+ax-y) under conditions -10 the author draws in the (a, ()) parameter plane the global bifurcationdiagram of trajectories around O(0,0). Notice that when na2.l < 0 ... 详细信息

关键词： Quadrtic systen Anti-saddle Bifurcation curve Limit cycle

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Magnetic fabrics in fault-related fold and its relation with finite strain: an example from Mingjiang thrust structures in Western Sichuan

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Progress in Natural science:Materials International 2007年第5期17卷 551-558页

作者： Jia Dong, Chen Zhuxin, Luo Liang, Hu Qianwei and Jia Qiupeng (department of earth {2.s, nanjing university, nanjing 21.093, china) [a]department of earth {2.s Nanjing University Nanjing China

The anisotropy of magnetic susceptibility (AMS) is a quick, effective and sensitive technique used to measure the weakly deformed sedimentary rocks, and also a reliable method to reveal the deforming mechanisms of fault-related folds. In Longmenshan front belt, a typical cross-section of fault-related folds is chosen to study the AMS. A total of 2.4 oriented specimens have been drilled at 2. different sampling sites which were distributed at the key structural positions of this structural section developed in the Xujiahe formation of the upper Triassic. Six elementary types of magnetic fabrics are recognized and established through this AMS study: Da sedimentary fabric; 2. an initial deformation fabric; 3) a pencil structure fabric; 4) a weak cleavage fabric; 5) a strong cleavage fabric; 6) a stretching lineation fabric. It has been found that most of magnetic fabrics are characterized by fabrics of weak deformation which belong to the pure-shear results of a pre-folding layer parallel shortening (LPS). In the fault-bend fold, almost all magnetic fabrics are the initial deformation fabrics of weak deformation, and denote that the deformation in the forelimb is stronger than that in the backlimb and no finite strain is shown in the footwall. While in the fault-propagation fold, finite strains are concentrated in the trishear zone where magnetic fabric results are approximately consistent with the estimated consequences of the kinematic model. The tectonic stress field indicated by the magnetic fabrics is basically the same along the whole structural section and shows a NW to SE compression and shortening which is accordant with the regional compressive stress field of the Longmenshan fold-thrust belt.

关键词： magnetic fabric finite strain fault-related fold trishear zone Longmenshan.

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Dynamic Mechanical Behaviour of Ultra-high Performance Fiber Reinforced Concretes

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Journal of Wuhan university of Technology(Materials science) 2008年第6期23卷 938-945页

作者：赖建中 department of Materials science & Engineering Nanjing University of Science & Technology

Ultra-high performance fiber reinforced concretes （UHPFRC） were prepared by replacing 60% of cement with ultra-fine industrial waste powder. The dynamic mechanical behaviour of UHPFRC with different fiber volume fraction was researched on repeated compressive impact in four kinds of impact modes through split Hopkinson pressure bar （SHPB）. The experimental results show that the peak stress and elastic modulus decrease and the strain rate and peak strain increase gradually with the increasing of impact times. The initial material damage increases and the peak stress of the specimen decreases from the second impact with the increasing of the initial incident wave. Standard strength on repeated impact is defined to compare the ability of resistance against repeated impact among different materials. The rate of reduction of standard strength is decreased by fiber reinforcement under repeated impact. The material damage is reduced and the ability of repeated impact resistance of UHPFRC is improved with the increasing of fiber volume fraction.

关键词： ultra-high performance fiber reinforced concretes split Hopkinson pressurebar dynamic repeated impact

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Variation of the Fe/Mn ratio of ferromanganese crusts from the Central North Pacific: implication for paleoclimate changes

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Progress in Natural science:Materials International 2005年第6期15卷 530-537页

作者： LU Zunli1**, LING Hongfei1*, ZHOU Feng1, JIANG Shaoyong1, CHEN Xiaoming1 and ZHOU Huaiyang2.1. State Key Laboratory for Mineral Deposits Research, department of earth {2.s, nanjing university, nanjing 21.093, china 2. Guangzhou Institute of Geochemistry, Chinese Academy of {2.s, Guangzhou 510640, china)department of earth & Environmental {2., university of Rochester State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China department of earth & Environmental {2. University of Rochester Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Contents of Fe, Mn and other elements in four ferromanganese crusts recovered from the central North Pacific are analyzed at high depth-resolution by electron microprobe for reconstructing factors controlling their deposition. Manganese (IV) in hydrogenetic ferromanganese crusts is mainly supplied as colloidal precipitates from the Oxygen Minimum Zone (OMZ), which concentrates high amounts of dissolved Mn (II). The iron is derived from carbonate dissolution and silicate particles of eolian dust. An increase in paleoproductivity during cooler climate would potentially lead to a decrease in Mn deposition due to enlargement of the OMZ which has a “temporary storage” effect for Mn. On the other hand, not affected by the OMZ, the iron entering the Fe-Mn crust would likely increase with the eolian dust input and surface productivity at glacial stages. As a result, the increasing Fe/Mn ratio should indicate a cooling climate. This is supported by the following observations. In the profile of the past 1 Ma, the variations of Fe/Mn ratio coincide with benthic oxygen isotope fluctuation in glacial-interglacial cycles. Three episodes with high Fe/Mn ratios, approximately at 2.6, 1.8 and 0.8 Ma, are detected within the past 3 Ma and coincide with major climate transitions and cooling events. The secular evolution pattern of Fe/Mn ratio in the Cenozoic is similar to the Pb isotope evolution which is mainly controlled by eolian dust and related to climate. The Fe/Mn evolution pattern is also broadly consistent with the global deep-sea oxygen isotope records. Therefore, Fe/Mn ratio recorded in the ferromanganese crusts may be a new proxy for climate change.

关键词： Fe/Mn ratio ferromanganese crust central North Pacific paleoclimate.

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Sensitive biosensing strategy based on functional nanomaterials

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science china Chemistry 2011年第8期54卷 1202-1217页

作者： JU HuangXian State Key Laboratory of Analytical Chemistry for Life science department of Chemistry,{2., nanjing 21.093, china 1. State Key Laboratory of Analytical Chemistry for Life science department of Chemistry Nanjing University Nanjing 210093 China

The first decade of the 2.st century has been labeled as "the sensing decade". The functional nanomaterials offer excellent platforms for fabrication of sensitive biosensing devices, including optical and electronic biosensors. A lot of works have fo- cused on the biofunctionalization of different nanomaterials, such as metal nanoparticles, semiconductor nanoparticles and carbon nanostructures, by physical adsorption, electrostatic binding, specific recognition or covalent coupling. These biofunc- tionalized nanomaterials can be used as catalysts, electronic conductors, optical emitters, carriers or tracers to obtain the ampli- fied detection signal and the stabilized recognition probes or biosensing interface. The designed signal amplification strategies have greatly promoted the development of stable, specific, selective and sensitive biosensors in different fields. This review in- troduces some novel principles and detection strategies in the area of biosensing, based on functional nanomaterials. The gen- eral methods for biofunctionalization of nanomaterials with biomolecules and their biosensing application in immunoassay of protein, DNA detection, carbohydrate analysis and cytosensing are also described.

关键词： nanobiosensing biosensors nanomaterials biofunctionalization signal amplification bioanalysis biological recognition

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The Sedimentologic-Geotectonic Evolution in the Jiangsu-Zhejiang-Anhui Region

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Acta Geologica Sinica(English Edition) 1989年第2期63卷 127-137页

作者： Xia Bangdong and Lu Hongbo department of earth {2.s, nanjing university, nanjing, Jiangsu Liu Linqun department of earth {2.s Nanjing University Nanjing Jiangsu

The Yangtze plate, extending from east to west in southern china, was formed about 800 Ma ago. Since the Sinian, two aulacogens trending east-northeast and connected at the east ends, have been initiated in the Jiangsu-Zhejiang-Anhui region on the east margin of the plate with a sedimentary sequence up to 10,000 m in thickness. At a later stage of sedimentologic evolution, flysch and molasse were produced. The flyseh was accumulated in the Late Ordovician, when the two aulacogens became bays that opened to the east; the elastic materials were derived from the Yangtze oldland on the northern and southern sides of the basins. The molasse was accumulated from the terminal Late Ordovician to the Middle Ordovician; the clastie materials came from an uplifted orogenic belt in the east. This indicates that a major change in the tectonic pattern of the basins has taken place.

关键词： Ordovician sedimentary accumulated Jiangsu Anhui northeast tectonic Yangtze sandstone margin

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Potash-rich volcanic rocks and lamprophyres in western Shandong Province:^(40)Ar-^(39)Ar dating and source tracing

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Chinese science Bulletin 2002年第2期47卷 91-99页

作者： QIU Jiansheng, XU Xisheng & LO Ching-HuaState Key Laboratory of Mineral Deposit Research of nanjing university, nanjing 21.093,{2. department of earth sciences, nanjing university, nanjing 21.093,{2. department of Geology, Taiwan Unive State Key Laboratory of Mineral Deposit Research of nanjing university Nanjing China department of earth {2.s Nanjing University Nanjing China department of Geology Taiwan University Taibei China

Highly precise 40Ar-39Ar dating results demon-strate that the ages of potash-rich volcanic rocks in western Shandong Province are 114.7-12..3 Ma, and that of the lamprophyres is 119.6 Ma. The potash-rich volcanic rocks have relatively high (87Sr/86Sr)i ratios ( 0.708715-0.711418) and distinctly negative εNd values ( -11.47--17.54), and are enriched in radiogenic lead (2.6Pb/2.4Pb=17.341-17.62., 2.7Pb/2.4Pb=15.52.-15.538, 2.8Pb/2.4Pb=37.563-37.684). Similarly, the lamprophyres also have quite low εNd values (-11.57 - -19.64). Based on the fact that the Sr, Nd and Pb isotopic compositions of potash-rich volcanic rocks are very consistent with that of the clinopyroxene separates, and by integrating comprehensive analyses of their tectonic settings, and extensive comparisons of the Sr, Nd isotopic composi-tions with that of the related simultaneous rocks, it is con-cluded that the potash-rich volcanic rocks and lamprophyres in western Shandong Province were most possibly derived from the partial melting

关键词： potash-rich volcanic rocks lamprophyres 40Ar-39Ar dating Sr-Nd-Pb isotope tracing western Shandong Province.

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Tribological Properties of Dimpled Surface Alloying Layer on Carbon Steel

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Journal of Wuhan university of Technology(Materials science) 2009年第2期24卷 218-222页

作者：万轶 department of Materials science & Engineering Nanjing University of Science and Technology department of Mechanical and Electrical Engineering Yingtian College

The effect of surface structure and coating on tribological properties of 45^# carbon steel disc was analyzed. A Nd：YAG laser was used to generate rnicrodirnples on steel surfaces. Dimples with diameter of 150 rn and depth of 50 rn were distributed in an orbicular array on disc surface. Then the alloying element Mo was sputtered to 45# carbon steel disc surface by means of double glow plasma technology. Diffusion Mo alloying layer with 30min thickness and high hardness up to 0.02. was formed on the disc surface. Tribological experiments of three types samples （smooth, texturing and texturing＋alloying） were conducted with a pin-on-disc tribometer. It is found that the dimpled-samples are most effective for reducing friction in comparison with smooth steel surthces, improving the lubricating state from boundary to hydrodynamic region.

关键词： laser surface texturing double glow plasma surface alloying technology carbon steel tribological performance lubricating state

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Measures and dimensions of fractal sets in local fields

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Progress in Natural science:Materials International 2006年第12期16卷 1260-1268页

作者： QIU Hua** and SU Weiyi(department of Mathematics, nanjing university,{2., china) [a]department of Mathematics Nanjing University Nanjing China

The study of fractal analysis over the local fields as underline spaces is very important since it can motivate new approaches and new ideas, and discover new techniques in the study of fractals. To study fractal sets in a local field K, in this paper, we define several kinds of fractal measures and dimensions of subsets in K. Some typical fractal sets in K are constructed. We also give out the Hausdorff dimensions and measures, Box-counting dimensions and Packing dimensions, and stress that there exist differences between fractal analysis on local fields and Euclidean spaces. Consequently, the theoretical foundation of fractal analysis on local fields is established.

关键词： local field p-series field Hausdorff measure and dimension Boxcounting dimension Packing measure and dimension Cantor type set.

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