最新刊期
卷 34 ， 期 4 ， 1995
- 摘要：This paper presents the theoretical computation of the air flow of the low-speed wind tunned and wing sections.The Bernoulli energy equation of air flow of theaxis fluid wind tunnel is estabished.Based on the Vanes pale theory of the axis windmechine and relatiuely movement air flow equation, we found the total pressure of thefluid pass through wing sections.Appling to the characteristic curve of wing model,theparameter of air kinetics of the vanes is obtained Through a series of experiments con-ducted on wind tunnel,the resistanca coefficiends of the air fluid has been found.By ap-plying above aquations and experimental data,the total pressure,flow and power effi-ciency of the wind tunnel are calculated here;and they almost coincide.The paperpoints out how the fixing angle of the wing sections can greatly influence the kineties pa-rameters and power efficiency of the wind mechine in the wind tunnel.Some examplesare presented.
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发布时间：2023-12-11 - 摘要：First,the mathematical model for complicated mechanical system is studied.Then the stability criterion of spinning-satellite fully filled with fluid(in uniform whirlmotion)in Lageriangian case is obtained by using the method of large-scale system withweighted V function.关键词：stability;large-scale system*
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发布时间：2023-12-11 - 摘要：We study the recurrence,ergodicity and mixing property of Markov chainformed by the(TAR)model in which the order,thresholds and paramerters are fixed.关键词：threshold autorgressive;recurrence;ergodicity;mixing*
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发布时间：2023-12-11 - 摘要：By using meson dielectric function constructured by standard σ-ω mixiingmethod, we calculate the collective excitation spectra(or dispersion relation)ofσ,ωmesons in nuclear matter, The ρ°-ωmixing effect on the collective excitation is studiedand the mixing effect on σ,ω dispersion relation is found small.关键词：dispersion relations;ρ°-ωmixing*
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发布时间：2023-12-11 - 摘要：We studied the persistent currents and Berry phase of mesoscopic ring in aninhomogeneous magnetic field with a ferromagnetic spin wave. We calculated the excita-tion energy spectrum of the quasiparticles and the charge currents.
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发布时间：2023-12-11 - 摘要：By using a perturbative canonical transformation and mean field theory,thesuperconducting transition temperature as a function of the dopping parameter for theHubbard-Hirsch model is calculated.It is shown that superconductivity is possible aslong as the hopping integral is large enough and that the superconductive region be-comes smaller due to existing of exchange integral.关键词：superconductivity;Hubbard-Hirsch model*
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发布时间：2023-12-11 - 摘要：Steady and transient photoluminesence（ PL ） spectra of{（ZnSe）202081378207012
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发布时间：2023-12-11 - 摘要：The characteristics and mechanism of extraction of Pd（Ⅱ）using 2-aminobenzothia-zole（ABT ） as well as the structure of extractable species were studied. The results showed thatpalladium can be extracted quantitatively with ABT into butyl acetate at pH 2. 0 whereas the ex-tractive effiencies of Pt（Ⅳ）, Rh（Ⅲ）,Ir（Ⅳ）were less than 5%. Palladium in organic phrasecan be stripped with thiourea. The composition of the extractable complex was determined as Pd-Cl22关键词： aminobenzothiazole;palladium;solvent extraction*
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发布时间：2023-12-11 - 摘要：n the presence of FeCl3.6H2O or Cu（Ⅱ）·amine complex, trie oxltiation couplingreaction of 3-hydroxy-1,8-naphthalic anhydride were studied in methanol,acetonitrile or water,3,3’-Dihydroxy-4 , 4’-bi-1,1’,8,8’-naphthalic anhydride was obtained in good yield.
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发布时间：2023-12-11 - 摘要：This paper reports preliminary results of the crystallization and the thermal degradationbChavior of high viscosity polypbenylene sulfide （ PPS ） of the sulfur method by thermoanalysis.The results are compared with PPS of the Na2S method,showing that the crosslinking structure,the thermal stability and the crystalline behavior of PPS of the sulfur method are affected by theimpurity.
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发布时间：2023-12-11 - 摘要：The Residue and fate of DDT in paddy rice of subtropical environment were studied byradionuclear tracing. The results obtained were as follows:Loss rate of DDT was rapidly underthe subtropical agroecosystem in Guangzhou, Using normal spray dosage in agroecosystem,DDTresidue in spikes of paddy rice is not over the trace standard( 7 mg/kg),The DDT residue was2. 1 mg/kg in rice bran,1.8 mg/kg in grain residue was 5. 8 mg/kg in rice bran,4.5 mg/kg ingrain of rice when applicated three times at tillering stage,booting stage and filling stage, It main-lv exists in stems and leaves.Therefore ,using normal spray dosage 1000 mg/kg DDT of 15 daysbefore harvesting stage in subtropical crops is safe.
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发布时间：2023-12-11 - 摘要：This paper dealed with mass individual rearing the larvae of the cotton leafworm,Spodptera litura F, on an artificial diet for propagating S, litura nuclear polyhedrosis virus(SINPV).The use of different combinations of six virus concentrations with three inoculating in-stars , six rearing temperatures with two inoculating instars and an artificial diet with a natural di-et,to sereen an optimal condition,The results showed that the maximal yield of SINPV wasmade when the larvae were treated with 3.85×10￣5 PIBs/mL in 3rd instar and3.85×10￣7 PIBs/mL in 4th instar.The optimal temperature was 2 4～27℃ when the larvae were infeeted in 4thinstar,nd the yield of the SINPV was higher rearing the larvae in an artificial diet than in a natural diet. here was a linear correlation between the cadver weights and the SINPV yields respectively (P<0. 01).The mortality rate of the infected larvae was directly proportional to temperature。关键词：Spokoptera litura;nuclear polyhedrosis virus;propagation
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发布时间：2023-12-11 - 摘要：The anatomical structures and ecological adaptations of Kandelia candel and Bruguteragymnorrhiza propagules were shown in this paper,The results showed that several peculiar struc-tures happened in mangrove propagules,for example,the differentiation of cotyledon.the endo-genecy of radicle and the existing of pericycle in hypocotyl etc。 ,which have never been found inother dicotyledons.It was demonstrated that the structural peculiarities of propagules and the phe-nomenon of vivipary in mangrove were the result of adaptation to the relatively saline habitat。The studies also exhibited convergent adaptation on both plant propagules。关键词：mangrove;propagules;vivipary;convergent adaptation;differentiation
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发布时间：2023-12-11 - 摘要：In order to make the Chinese language comprehensible to Western people,earlier Wade一Giles,and more recently,pinyin, have been used to phonectically transcribe Chinese personaland geographic names into Roman alphabets.Phonetically synonymous characters are common inthe Chinese language,and one pinyin syllable on average accounts for 16 different commonly usedcharacters plus 20 additional characters of less common usage, This phonectic synonymy resultsin loss of information when chinese personal and geographic names are transcribed into syllablesbecause these names alone have no context to help correctly interpret the original writing.There-fore,a monolingual database that convert and store Chinese data in Roman alphabets will presentambiguous information to both Western and Chinese colleagues.A bilingual(and possibly multi-lingual)database is preferable because it can archive the original information and simultaneouslypresents a translation of the original data in English,making the data comprehensible to a largeraudjence. An English一Chinese bilingual information system should possess the following functions :1) the database can store two formats of data ,i.e. Roman(English ) alphabets and Chinesecharacters :2 ) users may retrieve data in monolingual format(either English or Chinese ) orbilingual format(the same piece of data being displayed in both English and Chinese);and 3) thesvstem can automatically convert the key data from one format to the Other.Therefore,a bilin-gual information system will not require double data entry time in comparison to a monolingualsystem.We have built English -Chinese Bilingual Botanical Information System (BBIS95).Thesystem is compiled with the dBase langllage and UCDOS is taken as the Chinese platform。Oursystem provides all the three functions mentioned above, In addition,the system contains eithteenbilingual dictionaries with more than 250 000 records of taxonomic,geographic,personal,insti-tutional and referential data concerning Chinese and American plants.Data of multiple annota-tions from a single specimen sheet and multiple duplicates of a single collection deposited in differ-ent herbaria are properly recorded. The system also include interface with Geographic Informa-Department of Biology, Zhongshan University,Guangzhou 510275tion System(GIS) ,Image Processing and Multimedia。Some bilingual collection data from theherbarium of Sun Yatsen University(SYS ) have been made available on the Southeastern Re-gional Floristic Information System(SERFIS)at the University of Alabama,which is accessiblethrough the Internet computer network(Email to zxu@serfis.by.ua,edu for detail ).In the fu-ture, more Chinese data are expected on-line in similar ways。关键词：bilingual;English一Chinese;databas;botany;network
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发布时间：2023-12-11 - 摘要：The gold in large-scale Hetai gold deposit exists in two forms:isolate gold-mineraland dispersion phase,The former is mainly native gold,which occurs in inclusion,intracrys-talline failure and crack.ICP,electron microsprobe analyses and Au X-ray plane scanning showthat some of the gold may occur in the crystal lattice of sulfides as dispersion phase。Gold-bear-ing tellurobismuthite was first discovered in the mining area。关键词：occurrence of gold;isolate gold mineral;dispersion gold;Hetai gold mine
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发布时间：2023-12-11 - 摘要：Sonneratia is a genus of mangrove living in the tropical coasts.Its most concentratedarea is located in the coast line of South Asia,There are 4 species(S。 alba ,S,caseolaris,S. ovataand S。 hainanensis)occurring in extreme south of China,where their distribution is limited in theHainan island,about 19 degrees north latitude. Palynological studies undertaking along the coastsof south一east China,where the present mongrove is abeent of Sonneratia, revealed that Some ofpollen types belonging to this genus( especially S, alba and S, caseolaris)occurred in the sedi-ments of Late Pleistocene,particularly in the period between 40000 and 25000 a BP,Pollen as-semblages of this age contain a number of taxa, having affinities with modern tropical species andgroups.A sharp decrease and lately disappearance of this genus from Guangdong coast line tookplace at about 20000 a BP, which reflects the influence of environmental change during the latestglaciation episode, New mangrove associations restored during the Holocene is similar to that oftoday(absence of Sonneratia) ,which is living under the climate of pronounced mnscon patern。关键词： Sonneratia;Guangdong coasts;Late Quaternary;palynology;paleoenvironment
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发布时间：2023-12-11 - 摘要：The divisons of Guangdong province on new structure motion are:I Guangdonggreat massif area, Ⅱ Leizhou Peninsula area ; the Ⅰarea is further divided into:123
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发布时间：2023-12-11 - 摘要：In the paper,based on the prognosis of space instabilities of slopes and their mapping inChongqing city by information method,the random searching for the location of sliding surfacesand their failure probability prediction are made by selecting typical seetions from the two kindsof instable slopes.At the same time,the failure probability values( FP_s ) for this two kinds ofslopes are gaven。 Here,the shearing strength coefficients c and tan are considered as the ran-dom variables.Finally,the FP values are combined with the colour map which is drawn auto-matically by computer to show the instability degrees of slopes in Chongqing city。关键词： information method;failure probability;prognosis.mapping
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发布时间：2023-12-11 - 摘要：This paper discusses firstly two basic concepts in object-oriented technic :object and class, and then provides a object model which is used to analyse, design andimplement software system。
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发布时间：2023-12-11 - 摘要：Soil一vegetable transfer factors for radioiodine were measured by γ spectrom-etry as well as by total β counts method after￣(131)I solution was added to soil surface。The values of transfer factor with various migration periods and concentrations of￣(131)Iin soil and with various growth periods of vegetables are determined.The frequencydistributions and the variability of transfer factors are presented. From experimental da-ta measured with γ spectrometry, it is shown that the range of observed values is 1.28×10￣(-2)～2. 10×10￣(-1) and the geometric mean and geometric standard deviation are 5.05×10￣(-2)and 1. 96 respectively. Furthermore,it is observed that the values of transferfactors vary with the mass of vegetable and the temprerature and relative humidity in various seasons.
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发布时间：2023-12-11 - 摘要：The chemical constituents of the soft coral Sarcophyton ,molle collected fromthe South China Sea have been studied.his paper reports the isolation and structuralelucidation of three compounds,i.e.gorgosterol, 24-methyl-cholesterol and batyl al-cohol by means of spectroscopies and GC-MS.These compounds were first discoveredfrom Sarcophyton molle.
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发布时间：2023-12-11 - 摘要：A limonoid was isolated from shatinyu[Citrus grandis(L,)Osbeck]seedscolleted from Mei Xian,Its structure has been established as nomilin using elementalanalysis, MS, IR, ￣1H NMR and ￣(13)C NMR。
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发布时间：2023-12-11 - 摘要：Distributions of Hemiberlesia pitysophila Takagi in both parasite-releasingand check fields were negative binomial ones with the same k value,the difference in av-erage number of female adult scale per bunch of needles was ascribed to the parasitiza-tion.关键词： Hemiberlesia pitysophila Takagi;Coccobius azumai Tachikawa;negative bi-nomial distribution
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发布时间：2023-12-11 - 摘要：The seasonal variations of COD and BOD5of leachate liquid from wufengrefuse landfill site are studied. It also gives the assessment about the wastewater treat-ment system by investigations,关键词：refuse iandfill site;leachate liquid;treatment system of waste water;pollu-tants
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发布时间：2023-12-11
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