最新刊期
卷 34 ， 期 2 ， 1995
- 摘要：A generalized averaging method is used to analyze the resonant response of the strongly nonlinear oscillators. A comparison with the numerically calculated result shows that the generalized averaging method in this paper has its advantage.关键词： strongly nonlinear oscillators;resonant response;averaging method
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发布时间：2023-12-11 - 摘要：The sub martingale problems for reflected diffusions with Piosson jumps in ahalf-space are considered.The existence of solutions for sub-martingale problemswithout continuity assumptions on the coefficients is obtained.And from the solutionsof the sub-martingale problems,the existence of a weak solution is established for astochastic differential equation with Poisson jumps in a half- space with refectingboundary conditions.
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发布时间：2023-12-11 - 摘要：A sufficient and necessary condition of nearly uniformly smooth is given,It is shown that Banach space X is locally uniformly convex if and only if X is locally nearly uniformly convex and strictly convex and has(WM)property.关键词：nearly uniformly convex;nearly uniformly smooth;locally nearly uniformly convex.
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发布时间：2023-12-11 - 摘要：Let G be a balanced 2-connected bipartite graph with bipartlition(X,Y). Suppose for each vertex v of G,H is the subgraph induced by the vertices which are dis- tance 2 or 3 from v,and for each vertex u which has distance 3 to v,the degree d_H(u)of uin H is at least the numbor of the vertices distance 2 from v minus(d_F(v)-2).Then Gis Hamiltonian,where the lower bound of d_H(u) is sharp.
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发布时间：2023-12-11 - 摘要：The statistics of the Spinons and Holons in strongly correlated 2D-Hubbardmodel is studied.The static magnetic susceptibility and the gap equation of Spinons arecalculated by using the slave-Ferlnion method.We compare the results between slave-Fermion and slave-Boson,and believe that the slave-Fermion method can betterexplain the AFMLR of MT_cSC in low temperature.
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发布时间：2023-12-11 - 摘要：Damage profiles for l2keV,8 × 10￣(14)～2× 10￣(15)/cm￣2 As￣+ implanted Si samplesare determined by suitably optimizing the ellipsometric spectra. It is shown for the caseof very low energy iniplantation that the damage profile is plateau type and that there isno inside peak structure,The depth of damage is determined to be 12.5～16.0nm,which is consistent with the result measured by RBS/C technique,The ellipsometricspectroscopy is shown to be advantageous over RBS/C technique in resolution,thusproviding more details of dalnage profile with this work.关键词： spectroscopic ellipsometry;ion implantation;damage profile
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发布时间：2023-12-11 - 摘要：Cylindrical samples of sediments are obtained from 4 sea areas next to the Mirs Bay to the South China Sea. An N-type high purity germaium low background gamma spectrometry system has becn employed to measure the Pb-210 and the Cs-137 contents in the layered sam- plees.The sedimentation curves of Pb-210 and Cs-137 are acquired using the least squares fit method.The sedimentation rata at the four sampling sites are evaluated.our results show that the sedimentation rate decreases when the sampling sites are farther away from the Mirs Bay into the South China Sea,In particular,the rate calculated using the Pb-210 activities decreases from 0.46 to 0.27 cm/a,and that using the Cs-137 method from 0.38 to 0.10 cm/a,The Cs-137 method vields resuIts which are subiected to external disturbance to a greater extent,and is thus less reliable than the Pb-210 method.关键词：the Mirs Bay;γspectrometer;sedimentation rate;Pb-210 and Cs-137 radioactiv- ity isotopes
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发布时间：2023-12-11 - 摘要：A one-step procedure for shooting true colour rainbow hologram for white light re- construction is described.The method is based on adding another laser light into an electronic sep- arated colour plate of a colour photo or picture. The technique is shown to be low noise. high res- olution and colour fidelity,which is suitable for mass production.
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发布时间：2023-12-11 - 摘要：The novel compound 5,3’,5’-trihydroxy-7-methOxyflavone was synthe sized twi complete debenzylation of 5,3’,5’-tribenzyloxy-7-methoxyflavone,The latter was also selectively debenzylated to give the mono-and di-benzyloxyflavone.
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发布时间：2023-12-11 - 摘要：The conductivities of urea-LiCl,urea-NaCl,urea-KCl,urea-CuCl22222
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发布时间：2023-12-11 - 摘要：Poly（vinyl acetate-N-vinyl pyrrolidone）（P（VAc-Vp））was prepared by free- radical polymerization in solution. The reactivity ratios（r1212关键词：vinyl acetate;N-vinyl pyrrdidone;compolymer composition;reactivity ratio
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发布时间：2023-12-11 - 摘要：The mediated vector pLB38 was constructed by insertion the 800 bp fragment of CaMV35S promoter from the plasmid pBI 121 into the BamH I site between the CaMV 35S pro- moter and GUS gene of the pBI121 and screening the recombinants containing the directed dupli- cate of CaMV35S promoter with Xba I digest.The plasmid pBI121 and pLB38 were introduced into the Agrobacterium tumefaciens containing Ti plasmid pGV 3850 by triparental-mating tech- nique with the aid of helper plasmid pGJ23. The foreign genes in pLB38 and pBI121 were transferred into the tobcco plants using the leaf -disk co-cultivated method and two kinds transgenic plants were obtained. DNA / DNA dot blot and Southern blot with α-32P labelled probe containing 3kb fragment of CaMV 35S-GUS comfirmed that foreign genes were transferred and integrated into the trans- genic tobacco plant genome,The identification of the product of NPT II gene with NPT II dot as- say,GUS gene with GUS fluorescent assay proved that the foreign NPT II and GUS gene were expressed in transgenic plants.And the GUS activity in pLB38-transformed plants in which the GUS gene was controlled by two directed CaMV35S promoters was three-to four-fold higher than that in the pBI121-transformed plants in which the GUS gene is controlled by single CaMV35S promoter.These results suggested that the promoter number has effect on the expres- sion level of genes controlledy by these promoters.
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发布时间：2023-12-11 - 摘要：During sexual reproduction of Pseudourostyla there are four rounds of cortical reorganization in all. The first one is initiated in anaphase of the first meiotic division and com- pleted after separation of the conjugating mates into two exconjugants.The exconjugants have not UM,and about half of them do not possess buccal cirrus.The cytopharynx remains vestigial. The number of new AZM membranelles and other cirri is reduced compared to the vegetative cell.Afterwards,all or almost all ciliatures generated during the first reorganization disappear with the forma tion of the spherical paracyst.The second round begins towards the end of the paracyst stage,when the macronuclear anlage from which a vacuolated mass of DNA-poor ma- terial has been extruded,contracts.The second cortical development completes shortly before the macronuclear anlage divides or after it has generated 3-9macronuclei,and a micronucleus en- ters the first mitotic telophase,The cell gains a new UM,and a normal cytopharynx,and about two thirds of cells have buccal cirrus.The number of new AZM membranelles and other cirri is more reduced in contrast to the cell after the first reorganization. The third round follows closely the second.During the period,the development of ciliary primordia exhibits the same temporal sequence and spatial pattern as in physiological reorganization,but behavior of all 3-9 macronuclei which merge into a single whole first and then divide repeatedly is similar to that in binary fission,After the third reorganization,the cell possesses normal ciliature,but the number of membranelles and cirri remains reduced.Finally,the fourth round comes when the cell has about 20(13 ～ 30 ) macronuclei.The process and the way in the fourth is the same as in the third.After the fourth reorganization,the cell recovers the normal ciliature of the vegetative cell and undergoes the first binary after conjugation in one day.关键词：ciliate;sexual reproduction;development;cortical reorganization
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发布时间：2023-12-11 - 摘要：Gymnocypris przewalskii przewalskii (Kessler)and Nemachilus scleropterus Herzensteinare the only fish in te Qinghai Lake. Both of them are parasitized by two species ofacanthocephalans,Neoechinorhynchus qinghaiensis Liu et al.and Echinorhynchus gymnocyrii Liu etal.,which harbour in the intestine of the hosts. In the former host,E. gymnocyprii locates in theanterior section and N.qinghaiensis in the posterior section,but in the later host,the sites of twoacanthocephalan worms are not obviously different.Comparing concurrent infection with singlespecies infection,the site of N,qinghaiensis in the host G,przewalskii przewalskii moves backobviously and its intensity of infection in the host N.scleropterus decreased significantly,theniche overlaps of two parasites in two hosts decreased.The negative interspecific association oftwo acanthocephalan worms in two fishes are not significant.关键词：Neoechinorhynchus qighaiensis;Echinorhynchus gymnocyprii;interspecific relationship;Qinghai Lake
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发布时间：2023-12-11 - 摘要：In this paper,Choeradodis is reported as one new record from China,At the same time,one new species is described. he type specimen is kept in the Research Institute of Entomology,Zhongshan University,Guangzhou. Choeradodis yunnanensis,sp.nov. This species is closely related to C,Squilla Saussure 1869,but differs from the latter by following characters:the body length(45mm)is shorter than that of the tegmina (46mm)while the pronotum is apparently shorter than that of C. squilla. Female: unknown. Holotype:Jinghong County,Yunnan Province, 1987-Ⅳ-4,colleoted by Chen Zhen 一V8O。
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发布时间：2023-12-11 - 摘要：Based on hydrographical surveys carried out during the period of 1985～1991,theoretical consideration and numerical models,the present paper provides a brief analysis on thedynamics of huangmaohai estuary,emphasizing on the low frequency flow patterns andcirculation. Labeled water parcel trajectories reveals the important formation mechanism of themid-estuary bar. Four small scale dynamic structures are found in the estuary along the Northand East Channel which have profound effects on the sedimentation,They are from north to south(1)the vasf Yamen bi-direction jet systam,(2)vertical density driven circulation,(3)gorge jet current and(4)horizontal circulation. The effects of estuarine dynamics on the sedimentation processes,especially those concerning the river mouth bar are discussed.
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发布时间：2023-12-11 - 摘要：Baini formation,age of middle pleistocens,have been discovered recently in the northpart of the Zhujiang Delta. Its origin,age and paleoenvironmental signijicance lead to many con-troversies.However,on research on systematic sedimentological analysis had been done for thesedeposits.The authors,after a series of observations in the fields and analysis in laboratory,pte-liminarily affirm:①Baini Formation lays on the second-order rock-bed river terrace,and pos-sess a duality layer structure of fluvial sediments.②The granulometric,morphometric,andquartz surface features of the clasts show that the deposition took place in the fluvial environmentof which the hydrological ch a racters are different from the recent river system of the ZhujiangDeIta。③The pollen and clay mineral characteristics show that the deposit can not represent anevent of marine transRression,④Although the depositing age may be considered as Middle pleis-tocene,the accuracy of the TL dating data in some profiles needs further study.关键词：Zhujiang Delta;Middle pleistocene;Baini formation;sedimentary environment
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发布时间：2023-12-11 - 摘要：By using the daily data of rainfall amount in Zhujiang Delta and Guangzhou’ s sound-ing from March to August of 1976￣ 1983, the favorable and unfavorable environmental condi-tions of genesis of hard rain in Zhujiang Delta, which is situated in the tropics, are analysed.And the conditions obtained are compared with those in the extratropics. The conclusion in this pa-per could be helpful to the forecasting and understanding of hard rain in the area.
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发布时间：2023-12-11 - 摘要：This paper gives an effective algorithm for deciding of irreducibility and aperi-odicity of nonnegative matrices.As a nonconstructive algorithm for solutions,this is a typical example.
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发布时间：2023-12-11 - 摘要：The measurement on transfer coemcients from soilto greens for nuclides with ICP are reported briefly.The transfer coefficients from soil to Guangdong cabbageand rapeflower for Ba,Sr,Y,Zr are measured.关键词：ICP method;Guangdong cabbage and rapeflower;transfer coefficients
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发布时间：2023-12-11 - 摘要：The solid complex trioxinatoaluminium （AI （Ox）3ffrnrfnr3
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发布时间：2023-12-11 - 摘要：The water-soluble aromatic components in shaddock peel were analyzed by GC-MS and 41 compounds were identified including limonene,3-carene,linalool,terpi- neol,nootkatone etc.
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发布时间：2023-12-11 - 摘要：Aminopeptidase activity had two peaks during development of peanut(Arachis hypogaea L. ) embryos, which coincided with the synthesis of storage pro-teins. A weak activity peak of carboxypeptidase emerged in the late stage of develop-ment of embryo. Aminopeptidase might have an important role in modifying the struc-ture of peptides of storage proteins. Abscisic acid inhibited germination of embryos invitro, decreased activities of endopeptidase and carboxypeptidase, but aminopeptidaseactivitiy was not affected. Degradation of storage proteins in germinating embryos invitro during development was dependent upon carboxypeptidase. Endogenous ABA con-tent declined in germinating embryos. Results from Act-D and CHM treatment showedthat carboxypeptidase existed in cells of matured embryos but its activity was mainly in-hibited.
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发布时间：2023-12-11 - 摘要：With a large amount of evidence,this paper first confirmed that the new-discovered Changkeng gold-silver deposit in central Guangdong province is the biggestand richest hot spring genetic precious metal mine in China before now. The metalloge-netic processes have also been inquired into primarily.关键词：hot spring metallogenetic type;large-scale gold-silver deposit;Changkengin central Guangdong province
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