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    25 May 1995, Volume 34 Issue 3
    A New Asymptotic Method in the Problem of Hydrodynamic Stability
    Zhang Diming; Tian Chuan;Huang Hai
    1995, 34(3):  1-9. 
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    In this paper,the problem of hydrodynamic stability is studed.Taking plan-poiseuille-flow,as an example,a new asymplotic method proposed for overcomieng thelimitation of κ-σ method in nonlinear oscillation theory,is extended and is applied to theproblem of hydrodynamic stability. By a comparison with those of using κ-σmethod,itwas shown that this new asymplotic method in the study of hydrodynamic stability issuccessful. 

    C ̄(1,a)Regularity for Minimizers of a Functional With Nonstandard Growth Conditions  
    Liang Xiting
    1995, 34(3):  10-13. 
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    Consider on G an integral functional of which the integrand depends on thegradient of u and on a parameter ε and satisfies certain nonstandard growth conditions。The local boundedness of the minimizer of the functional is proved. Furthermore, if theminimizer,u,satisfies suitable restrictive conditions,then it has locally Hldercontinuous fisst gradient;and on any compact suoset of G the Holder coefficient and theHolder exponent of the gradient of the minimizer are independent of u and ε,theminimizer and the parameter,respectively。 

    Elgenvalue Problem of Elliptic Euler Equations with the Natural Growth Condition
    Shen Yaotian;Ma Ruaian
    1995, 34(3):  14-19. 
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     We consider the eigenvalue problem of elliptic Euler equations under the natural growth condition,we consider multiple integrals of the F(x,u,Du)then weknow that the variational problem under some sufficient conditions relevant to F(x,u,q),yields its solution.A similar method can be used to prove the existence of thesolution to the variational problem I(u),which I(u)is restricted on E. 

    Software Development Methodlogy for Management Information System
    Lai Jianhuang;Li Qiaoxiang
    1995, 34(3):  20-25. 
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    The importance of software-engineering-development speed in managinginformation system(MIS)development has been expounded.According to thecharacteristic of MIS and with his experience in software-developing,the authorintrodued a super-grading method which fits middle and small software development。The method not only retains the advantage of other system software development butalso speed up MIS software development。 

    The Selfsimilar Diffraction Spectra for a One-dimensional Quasi-periodic Grating
    Huang Xiuqing Mo Dang
    1995, 34(3):  26-30. 
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     A kind of one -dimensional quasi-periodic grating is designed.Theselfsimilar diffraction spectra are evaluated and the influence of the phason strength onthe structure factor is studied。 

    Generalized Admittance Circles
    Fan Yangcai; Li Jingde; Fu Desheng
    1995, 34(3):  31-35. 
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    The concept of generalized admittance circles(GAC)is presented based onthe analysis of the cole-cole plot, admittance circles of piezoelectric vibrator andcomplex impedance of granular boundary ceramics.It is shown that GAC is a veryuseful concept for the measurement of dielectric materials.Debye relaxation is found todepend not only on the micro-mechanism of the matter,but also on the method ofmeasurement.The effect of inductance is observed in the electronic ceramics. 

    Preparation of Composite Ribbon of Room-temperature Magnetic Refrigeration
    Shao Yuanzhi;Lin Guangming
    1995, 34(3):  36-39. 
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    The Cu-sheathed rolling techuique is developed for forming a practical compoite rib-bon of room temperature magnetic refrigerant Gd1-z Tbx powder. The as- prepared ribbon, withboth excellent surface state and even thickness,shows good magnetocaloric effect.A discussionconcerning influence of the preparing parameters on magnetocaloric effect is given in detail。 

    Interface Study of Alumina Short Fibre-Reinforced Al-Si Alloy Matrix Composite
    Lan Guoqiu;Tu Mingjing;Li Wei;Li Kun Human
    1995, 34(3):  40-44. 
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     The interface of Al2O3f/Al-Si alloy matrix composite is examined by means of EP-MA,and it is found that there is accumulation of Mg at the interface,The analysis of tensile frac-ture shows that Al-Si alloy wets alumina fibres very well,and that coherent and semicoherentmixed interface is formed increasing the interfacial strength;Alumina fibres are sheared fracture,and no fibre pull-out is observed. The detailed study on the interface with AES indicates that thepeaks shape of Si and Al at the interface is different from that in the matrix due to the formationof the coherent and semicoherent mixed interface. 

    Gas-Phase Polymerization of Ethylene with Highly Active catalyst───the Effects of Alkylaluminium Compounds, Electronic Donors and Hydrogen
    Wu Qing;Wang Haihua;Lin Shangan
    1995, 34(3):  45-50. 
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    Gas-phas polymerizations of ethylene have been performed over a prepolymerizedMgCl2-supported titanium catalyst.The effects of alkylaluminium compounds and electronicdonors in both the prepolymerization and gas-phase polymerization stages on the catalytic activitywere oberved, The catalytic activity unchanged by altering the alkylaluminium compounds in theprepolymerization stage,while it was changed by altering the alkylaluminium compounds in thegas-phase polymerization stage in the order of Al(i-Bu)3>AlEt3= Al(n-Oct)3>>AlEt2Cl.Addi-tion of the electronic donors into the prepolymerization system slightly increased the catalytic activ-ity,whereas addition of the donors into the gas-phase polymerization system depressed the catalyt-ic activity.The effect of H2 on the catalytic activity and molecular weigh t of the preducts is alsopresented, 

    Study of the Allylic Oxidation and Halogenation of Monoterpenoid
    Wang Zhiciai;Zheng Qihuang;Gao Bi;Fan Shiyan
    1995, 34(3):  51-56. 
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     Monoterpenoid,which is a basic fragment of cembranolide,was synthesized startingfrom guraniol,geranial and linalool specially produced in south China area. This paper laid em-phasis on the study of the allylic oxidation and halogenation. The suitable reaction mechanismwas proposed. 

    The Diels-Alder Reactions of 4,4-Dimethoxythiobenzophenone with Sorbic Acid and Its Methyl Ester
    Huang Jingke ;Wei Chunmei
    1995, 34(3):  57-61. 
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     The Diels-Alder reactions of 4,4-dimethoxythiobenzophenone(2)with sorbic acid oc-curred at room temperature to afford 83%cycloadduct and 17%isomer,while the reaction withsorbic acid methyl ester occurred at room temperature and the main cycloadduct was formed. The kinetic study showed that the Diels-Alder reactions of 2 with sorbic acid and its methylester are much slower than those with trans-1-substituted -1,3-butadienes.The reactions becomethe reversible due to the fact that the dienes have two substituted groups at C1 and C4, and theiradducts are unstable. 

    Synthesis and Photopolymerization Kinetics of Acrylated Isocynates
    Du Xiuying;Liang Zhaoxi
    1995, 34(3):  62-66. 
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     In this paper,two unsaturated acrylated isocynates(AAT,NAT) were synthesizedfrom 2.4-TDI,equimolarβ-Hydroxy propyl acrylate and aliphatic alcohol by addition reaction.The photopolymerization of monomers under UV light radiation at 40℃ with the use of Darocur1173,DEAP,DMPA as the photoinitiator have been studied by dilatometry. The study hasshown that the activity of monomer NAT is higher than that of AAT.the efficiency of photoini-tiator decreased in the order of DEAP>DMPA>Darocur 1173 for both monomers,and the poly-merization rate was greatly influenced by solvent. 

    Effect of External Divalent Cations on the Activation Process of Na─channels  
    Hui Ping; Wang Jimei
    1995, 34(3):  67-72. 
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    We propose a model to discribe the effect of divalent cations on the activation processof Na─channels.The following are the results obtained from the model: For the activation pro-coss of Na─channels there exists a threshold of depolarization voltage;The increass of concen-tration of divalent cations results in increase of the threshold; The relaxation time of activationprocess and the maximum degres of activatcatcation are significantly related with the concentra-tion of divalent ions and with the depolarization voltage,The results mentioned above agree wellwith those obtained through experiments qualitatively and semi─quantitatively. 

    On the Endemic Genera of the Spermatophytic Flora from Guangdong I.Endemism and Statistics and Analysis of the Endemic Genera
    Liao Wenbo;Chang Hungta
    1995, 34(3):  73-80. 
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    Genera endemic to China in the spermatophyte flora of Guangdong province consistedof 40 families 75 genera and about 128 species;the percentages possessing the same group of Chi-na were:45.4% of families,23.4% of genera,and 17.0%of species.Among them containedplenty of the palaeoendemic genera,neoendemic genera,local endemic genera,and so on,ofwhich all were genera characteristic of Guangdong flora and formed a centre of endemism to Chi-na in Southwest Guangdong to Southeast Guangxi.Based on the analysis of the distribution ofthose endemic elements and ancient floristic histories in Guangdong province and its neighbour-hood ,Guangdong was one of the key regions of the orig ins of the Chinese flora or the Cathaysianflora. 

    Plantae Rockianae
    Miau Ruhuai
    1995, 34(3):  81-83. 
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    In this paper 20 species collected by Joseph F.Rock from southeastern Xizang(Tibet),northwestern Yunnan and southwestern Sichuan of China in April-October 1932 are reported。Among them 14 species belong to Liliaceae,2 Iridaceae,1 Orchidaceae,1 Zingiberaceae, 2 Gen-tianaceae and 1 Compesitae of which 3 new taxa are proposed,namely Lilium Rockii Miau sp.nov.,Roscorea sichuanensis Miau sp.nov,Swertia tetragona Miau sp.nov,they are maifilydescribed and but then other species follow after them as an enumeration in this paper。 

    Accumulative Effect of Chlamydomonas and Tribonema in Waste Water of Salphate of Copper  
    Zhong Heng;Xie Yongquan;Liu Meiling;Zhang Yishun
    1995, 34(3):  84-88. 
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    When 0.5 mg/L CuSO4 was added to the culture medium, the growth of Chlamydomonaswas broken. However,those that had adapted to the waste water with 525 mg/L CuSO4 grew toa large number of pure population,and highly cumulated Cu(41.63%),Fe(34. 92%),Zn(10.09%)and other metals.But Chlamydomonas of pure cultures do not contain these heavy met-als.The algae grown in waste water of CuSO4 with the single pure population growing.In somewater hole,the number of cells of Chlamydomonas was as high as 2440×10 ̄6 cells/ L in earlysummer.The number of cells(growing quantity) of Chlamydomonas not only positively correlatedwith the ionic content of Cu,but also to the ionic content of Ca,and Fe.In some water hole,filaments fo Tribonema are 2997.97μg/g and 38109.76μg/g respectively,500 times and 381times the normal needful quantity of plants.The Tribonema filaments copper cumulative factor of3,4 and 6 indicates that the cumulation of Cu positively correlated with the Cu content in the wa-ter.The copper content of Tribonema chlorophyll is as high as 1756.44μg/g showing that thecomplexing content of chlorophyll molecule and copper was corresponded to 59%of the total cop-per content of the algal filament.In control group(beside the waste water of CuSO4),thechlorophyll molecule coppr of Salxinia natans (belonging to water fern) only contained 52.8μg/g;but the Mg content was as high as 4963.79μg/g, which was 10 times higher than Tribonemachlorophyll molecule Mg. The waste water of CuSO4 containing Fe and Ca compound may elimi-nate the toxicity of CuSO4 from the algae. Chlamydomonas and Tribonema had adapted themselves tothe waste water of CuSO4,and highly cumulated Cu , Fe, Ca and other elements,and chloro-phyll molecule Mg were replaced by Cu and other elements in physiological reaction。 

    Study on the Amino Acid Ages of Fossils Teeth and Mixed-Deposition Phenomenon in Some Caves
    1995, 34(3):  89-94. 
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     The degree of amino acid racemization and ages of dozens of fossils teeth in deposit ofsome caves distributing in Zhaoqing,Yunfu,Fengkai,Yangchun in west Guangdong provincewere analyzed in this paper.The ages of these fossils were dated to be 2000~20000a BP,whichsuggests that they deposited from late stage of late Holocene to late stage of late Pleistocene. Onthe basis of these data,it was found that not only the fossils of the same period,but also the fos-sils of different periods were deposited in the identical layer in some caves.Therefore,it was in-ferred that the cave deposit may have undergone reformation and transpOrtation once again beforedepositing in the cave,which made fossils of various periods mix up in the same layer.This paperprovides some new evidences and a new method for studying more details on the evolution ofQuaternary mammal and on the paleoenvironment and paleoclimate。 

    The Genesis of Corundum Megacrysts Related to Alkali Basalt in Hainan
    Qiu Zhili;Qin Shecai;Pang Xuebin
    1995, 34(3):  95-101. 
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     Penglai of Hainan province is one of the important localities of sapphire in China.Thecorundum megacrysts ane related to Cenozoic alkali basalt and have the following features: hav-ing clear surface melted structure and containing Zircon&Tiniobite &CO2-bearing fluid melt-ing inclusions with the homogeneous temperatures of 1125~1265℃,being rich in light REE andhaving the REE distribution pattern similar to that of hypersthene granite,mother rock of peg-matite-type corundum , but different from those alkali basalts.Based on the above-mentioneddata,the authors think the corundums were produced in the enviroment with rich incompatible el-ements & volatile components,not the result of crystallization of basaltic magama. The forma-tion of corundums may be related to the crust substances collapse resulted from rift and its assimi-lation & contamination and metasomatism with ultrabasic magama during the formation ofbasalts.The megacrysts are the result of metamorphism& metasomatism at high pressure near theboundary between the crust and the upper mantle。 

    The Characteristics of the Newly-designated Cities and the Impacts on the Spatial Pattern of Chinese Cities since Late 1970s
    Yan Xiaopei;Cai Xiaobo
    1995, 34(3):  102-108. 
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    Since the economic reform in 1978,the dramatic increase of Chinese cities hasbeen accompanying the rapid development of economy.This paper focuses on the newly designated cities since 1978.Attention is initially paid to the characteristics of thenew cities,including the increase number and rate, the designation ways , provincial dif-ferences,and spatial pattern etc. Then their impacts on the city distribution are exam-ined.In addition,the problems related to the designation are discussed in hopes of pro-viding the references for improving the designation standards,constituting a rationalcity distribation,and supervising the Chinese urban development。 

    Sedimentation Divisions of Pearl River Mouth
    Chen Yaotai
    1995, 34(3):  109-114. 
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    The Pearl River mouth can be divided into five sedimentation divisions ac-cording to hydraulic environments,types,sizes and ingredient of the sediment,as wellas sedimentation rate and topogrophy.Sandy sedimentation division of runoff type is anactivest locality of sedimentation function in the Pearl River mouth and in chief of riveraction。Muddy sedimentation division of tidal type is famouset of tidal action,and afaster sedimentation area for fine sediments in the modern river mouth is withstood byshelf-water.Sdimentation division of relict sand is a local corrosion,and by chief ac-tion of invasion and control of shelf-water。 Mixing sedimetation division of the modernriver mouth and mixing sedimentation division of the shelf’s shallow sea-relict sedimentare located between theabove-mentioned three sedimentation divisions; their hydrauliccondhions and sedimentation characters have the attributes of the transhional environ-ment. 

    Question to the Validity of the Dinosaur 18s rDNA Fragment from Xixia,Henan
    Qu Lianghu; Shi Suhua; Zhou Hui
    1995, 34(3):  115-119. 
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     Based on their structural characteristic,the nucleotide sequences of DA18S1and DA18S7 were aligned and compared with rDNA sequences from eight other species.The result of our analyses showed that neither of the two sequences was dinosaur rDNAfragment.DA18S7 turned out to be a plant rDNA frgment(more than 94%homologywith Malpighia coccigera),however,DA18S1 had high homology(88.3%and 89%)with two compared Fungi rDNA other than vertebrate rDNA(67.8%~74.1% only) 

    Field Experiment of Hybride Papaya Artificial Seeds
    Huang Junchao;Ye Kenan;Li Baojian
    1995, 34(3):  120-121. 
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    This paper reports field experiment of hybride papaya artificial seeds wasdone successfully for the first time. 

    Analysis System for the Detection of Stable or Transient Noise and Vibration
    Zhao Jian; Chen Wenbo; Xiao Kuiying; Liang Ruobiao
    1995, 34(3):  122-124. 
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    This system is produced for the analysis of stable or transient signals of noiseand vibration,By employing this system,technical parameters about noise &vibrationin engneering can be obtained,thus the funtion of noise & vibration detection is real-ized.In the development of this system,several kinds of advanced techniques in com-puter science,electronics,mechanics,digital signal processing are employed.The sys-tem has reached a high level in its design,functions and propertries。 

    Self-pumped Phase Conjugation of a Mn-doped KNSBN Crystal
    Zhang Yueli;Xie Xiangshou; Zhou Changshi; Zhu Derui; Mo Dang
    1995, 34(3):  125-128. 
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    The Mn-doped(KNa)0.1 (Sr0.6Ba0.4)0.9Nb2O6(KNSBN)crystals grown,poledand polished in this experiment were discribed. The self-pumped phase conjugation ofMn-doped KNSBN was observed at 632.8nm using He-Ne laser. The self-pumped phaseconjugation reflectivity as high as 70%was measured. The reflectivity as function of theincident angles and the incident intensities as well as the relation of the response time tothe incident intensities were studied experimentally。 

    Studies on the Chemical Constituents of the Marine Mollusc, Siphonaria japoniaⅡ)
    Fu Xiong;Zeng Longmei;Su Jingyu
    1995, 34(3):  129-132. 
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     Two polypropionate derivatives 1 and 2 have been isolated from the marinemoll use of Siphonaria japonia. Compound 1,reported previously,was further studiedby long range C/H correlation achieved by the use of the HMBC sequence。The struc-ture of compound 2 was elucidated with the spectral data of IR,UV,MS, ̄1H and ̄(13)C NMR。