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Chinese Journal of Aeronautics 1997年第2期10卷 104-109页

作者： Zhang Fang Zhu Demao(Vibration Engineering Research institute, nanjing University ofAeronautics and Astronautics, nanjing, china, 210016) Vibr. Engineering Research institute Nanjing Univ. Aero. and Astronaut. Nanjing 210016 China

A dynamic load identification model of structural system based on the gener-alized orthogonal polynomial theory is provided, and the least Square discrete algorithm foridentifying the dynamic load is supplied. The main key is that the convolution relationsbetween the input and output of the system in time domain are transformed into linear oP-erators in generalized orthogonal domain. The new theory is fully tested and verified bythe dynamic analysis l 'modal test and dynamic load identification teSt of a simulation speci-men- It is shown that the method has some advantages, such as the simple dynamic cali-bration test, the high identification accuracy, especially for the transient load with shortsampling. These are very useful in engineering applications.

关键词： dynamic loads load identification dynamic structural analysis modal experiment vibration

ON TWO CONJECTURES OF THE QUADRATIC DIFFERENTIAL SYSTEMS

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Chinese Annals of Mathematics,Series B 1997年第4期18卷 429-434页

作者： ZHANG XIANG institute of Mathematics,nanjing Normal University,nanjing 210097,china 南京师范大学数学所江苏南京

Two conjectures in the qualitative theory of quadratic differential systems are proved under certain conditions.

关键词： Quadratic system Limit cycle Dulac function

Quantitative Evaluation for Drawability of Sheet Metal

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Journal of Materials Science & Technology 2005年第5期21卷 763-766页

作者： Zhiqing XIONG and Xuemei YANGDepartment of Mechanical Engineering, nanjing institute of Technology, nanjing 210013, china Department of Mechanical Engineering Nanjing Institute of Technology Nanjing 210013 China

The theoretical evaluating method is given for the drawability of the sheet with normal anisotropy. The general solution on the cracking load of deep-drawing is deduced, which is based on three kinds of hardening curve of materials most in use. The distributions of stress and strain in the deformed region and the drawing force are obtained by the numerical method. The limiting drawing ratio is calculated through computer-aided simulating test. The experiments of deep-drawing to four kinds of sheet metals express that the relative errors between the predictive and the experimental results about the cracking load and the limiting drawing ratio are within 5%. The drawability of common sheet metals can be quantitatively evaluated in precise terms by means of the theory and the method advanced in this paper.

关键词： Sheet forming Deep-drawing Formability Drawability

Principal aspects of the Ordovician biotic radiation

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Science china Earth Sciences 2010年第3期53卷 382-394页

作者： ZHANG YuanDong,ZHAN RenBin,FAN JunXuan,CHENG JunFeng & LIU Xiao LPS, nanjing institute of geology and Palaeontology, Chinese Academy of Sciences, nanjing 210008, china LPS Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China

The Ordovician radiation is among the major bioevents in earth history that have drawn great attention from geologists all over the world, and there have been hundreds of publications treating various aspects of this radiation. The study of the event involves a broad spectrum of research fields and concerns many scientific questions. Many opinions and hypotheses have been proposed on the triggering and controlling factors of the radiation. Herein the authors critically review the study of the Ordovician radiation and dissect four principal aspects by synthesizing the studies over the past years: (1) relationships of the radiation to fossil clades, ecotypes, and environments, such as water depth, latitude, and climate; (2) the ecological structure and food webs of Ordovician marine organisms; (3) fossil records and true biodiversities; and (4) likely triggering and controlling factors of the Ordovician radiation. The authors also recommend approaches to furthering studies of these aspects.

关键词： Ordovician biotic radiation guild food web fossil record mechanism

On the evolution and histology of some Cambrian protoconodonts, paraconodonts and primitive euconodonts

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Science china Earth Sciences 2004年第7期47卷 577-584页

作者： DONG Xiping Department of geology, Peking University, Beijing 100871, china Laboratory of Palaeobiology & Stratigraphy, nanjing institute of Ge-ology and Palaeontology, Chinese Academy of Sciences, nanjing 210008, china Department of geology Peking University Beijing China Laboratory of Palaeobiology & Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China

Previous reports on the morphological evolution of protoconodonts and paraconodonts are reviewed. The evolutionary trends exhibited by species of the protoconodont genus Gapparodus and the paraconodont genus Westergaadodina are discussed. Based on the present study on histology, genus Paibiconus is protoconodont, while genus Yongshunella is paraconodont (fig. 1 (a)). However, the nature of Huayuanodontus has not been fully understood so far. Recently, the transitional form New Gen. Sensu Miller, 1980 of late Late Cambrian has been found in Hunan Province, South china. It is considered as the Sister-Group of Proconodontus. Moreover, another kind of transitional form of middle Late Cambrian and late Late Cambrian between Prooneotodus notundatus and Pnoconodontus, which looks like Prooneotodus notundatus in gross morphology, but has anterior and posterior costae, has also been found in Hunan, South china. This kind of transitional form is believed to be probably the real intermediate link between Prooneotodus rotundatus and Pnoconodontus, and Prooneotodus rotundatus is most probably the ancestor of Proconodontus. The two transitional forms noted above are all euconodonts by the study of their histology. Unlike the euconodonts of Post-Cambrian, the evolutionary relationships among the species of protoconodonts, paraconodonts and the primitive euconodonts could not be made clear without the histological study on them.

关键词： protoconodonts, paraconodonts, evolution, histology, Cambrian.

Occurrences of Permian radiolarians in central and eastern Nei Mongol(Inner Mongolia) and their geological significance to the Northern china Orogen

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Chinese Science Bulletin 2004年第24期49卷 2613-2619页

作者： SHANG Qinghua nanjing institute of geology and Paleontology,Chinese Academy of Sciences,nanjing 210008,china institute of Vertebrate Paleontology and Paleoanthropology,Chinese Academy of Sciences,Beijing 100044,china nanjing institute of geology and Paleontology Chinese Academy of Sciences Nanjing China institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China

The Zhesi (Jisu) Formation of the Middle Per- mian in Nei Mongol (Inner Mongolia) was commonly con- sidered to be a shallow marine sequence. Here I report the radiolarians found in the argillite bed of that formation in Zhesi and Xilinhot areas. This fact indicates a deep marine sedimentary facies persisted during the Middle Permian, and suggests that the ocean between the North china Block and Siberian Craton was not closed until the Late Guadalupian. The suture of this two blocks is probably extends along the Linxi ophiolite belt, south of the Hegenshan ophiolite belt.

关键词：造山带地质意义内蒙古放射虫二叠纪

A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW china

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Science china Earth Sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12, TANG Lingyu1, FENG Zhaodong3,4, ZHANG Hucai2, WANG Weiguo3 & AN Chenbang3 1. nanjing institute of geology and Palaeontology, Chinese Academy of Sciences, nanjing 210008, china 2. Nanjng institute of Geography and Limnology, Chinese Academy of Sciences, nanjing 210008, china 3. Environment and resources College, Lanzhou University, Lanzhou 730000, china 4. Beijing Normal University, Beijing 100875, china nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing China Nanjng institute of Geography and Limnology Chinese Academy of Sciences Nanjing China Environment and resources College Lanzhou University Lanzhou China Beijing Normal University Beijing China

With the support of 18 AMS-14C data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2 to 11 ka B.P. in the Jingning area. Over the period of 44―29 ka B.P. (MIS3), coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 23 ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3, further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

Yangtzedonta and the early evolution of shelled molluscs

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Chinese Science Bulletin 2001年第24期46卷 2103-2106页

作者： QIAN Yinanjing institute of geology and Palaeontology, Chinese Academy of Sciences, nanjing 210008, china nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing China

The holotype of Yangtzedonta Yu, 1985 and its type species, Y. primitiva Yu, 1985, is an incomplete specimen of Xianfengella prima He et Yang, 1982. Therefore, based on the principle of priority, the names Yangtzedonta and Y. primitiva Yu (1985) should be abandoned. The fact that ventral valve of Xianfengella is bilaterally symmetrical indicates that they are not the left valve of a bivalved mollusc, as originally proposed by Yu. At present, the oldest certain bivalve is Xianfengoconcha elliptica Zhang, which occurs in the Early Cambrian Qiongzhusi Stage in china. The oldest known rostroconch is Heraultipegma yunnanensis He et Yang, which first occurs in the third small shelly fossil assemblage zone of the Early Cambrian Meishucunian Stage. The oldest known monoplacophoran, Maikhanella pristinis (Jiang), first occurs in the first small shelly fossil assemblage zone (Meishucunian Stage). Evidence derived from analyses of shell morphology, mode of growth, histology, and stratigraphic occurrence suggests

关键词： Yangtzedonta bivalves Xianfengella brachiopods enig- matic fossil.

EFFECT OF TURBULENCE ON BOUNDARY LAYER TRANSITION MEASUREMENT

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Chinese Journal of Aeronautics 1993年第2期 90-94页

作者： Zheng Guo-feng (nanjing Aeronautical institute,nanjing,china,210016)

An experimental study of the effect of stream turbulence on some measuring methodsof boundary layer transition has been conducted, which indicates that the method to measurerms leyel of random signal is more effective for detecting boundary layer transition,because, in transition process, difference of rms level of random signal is larger and ***, in this paper, the effect of stream turbulence and inputting acoustic with differentfrequencies on rms value distribution of velocity fluctuation in transition region hasbeen studied, and it is found that there is a maximum rms value of fluctuation and it is locatednear 0.2σ high, in spite of the existing turbulence and noise. Finally, it is suggestedthat a general criterion of judging the beginning and ending points of transition regionmust be studied further for precision of transition region measurement.

关键词： EFFECT OF TURBULENCE ON BOUNDARY LAYER TRANSITION MEASUREMENT

Speciation of the genus Arthricocephalus Bergeron, 1899 (Trilobita) from the late Early Cambrian and its stratigraphic significance

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Progress in Natural Science:Materials International 2006年第6期16卷 614-623页

作者： YUAN Jinliang, ZHAO Yuanlong and YANG Xinglian (nanjing institute of geology and Palaeontology, Chinese Academy of Sciences, nanjing 210008, china College of Resource and Environment of Guizhou University, Guiyang 550003, china) nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China College of Resource and Environment of Guizhou University Guiyang 550003 China

The genus Arthricocephalus Bergeron, 1899 is revised, and Halipanktos Balker & Peel, 1997 is suggested here as a senior synonym. The subgenus Arthricocephalus (Arthricocephalites) Chien & Lin in Lu et al. , 1974 is considered as a separate genus. Of the 20 previously assigned species of Arthricocephaius (Arthricocephalus) Bergeron, 1899, Arthricocephalus (Arthricocephalites) Chien & Lin in Lu et al. , 1974, Arthricocephalus (Euarthricocephalus) Ju, 1983 are lumped into eight species. The speciation trend of Arthricocephalus and Arthricocephalites is demonstrated based on their stratigraphic occurrences. It not only enhances the resolution of the biostatigraphic zonation in the uppermost Lower Cambrian, but also represents a potential candidate to define the Duyunian stage. The base of the stage is suggested at the first appearance datum (FAD) of Arthricocephalus chauveaui Bergeron, 1899 within the evolutionary lineage from Ar. jiangkouensis Yin in Yin & Li, 1978 to Ar. chauveaui in a global scale.

关键词： late Early Cambrian Duyunian stage speciation of Arthricocephalus and Arthricocephalites biostratigraphy.