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    Analysis on the Forest Communities of Dinghushan,Guangdong
    Ⅳ.Similarity and Cluster Analysis Wang Bosun (Zhongshan University)Peng Shaolin (South China Institute of Botany,Academic Sinica)
       1985, 24 (1): 31-38.  
    Abstract9)      PDF (564KB)(14)      

     The changed cases of the stairs along height above sea level in Cryptocaryachinensis Community on Dinghushan,and the communities comparison to 10 fo-rest communities on Dinghushan and Nankunshan and Jigongkeng are analysedwith the measurement of species similarity and cluster analysis.The relation a-mong 10 forest communities and the leaning of the development of some communi-ties are exposed.The analysis methods are valued.It shows that percentage of similarity is thebest among three methods of the measurement of species similarity.Cluster ana-lysis is a better method which is widely used.

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    Cited: Baidu(97)
    The Continental Drift and the Development of the Flowering Plants
    Chang Hang-ta
       1986, 25 (3): 4-14.  
    Abstract4)      PDF (966KB)(7)      

    According to the continental drift theory,the ancient ecology of the climateand geological vicissitude of the Cathaysian,Australian,South American,Afri-can,North American,Tropical Asian and Indian ancient lands or landmassesthroughout the Mesozoic Period are discussed.Subsequently,the characteristicsof the flowering floras of the ancient lands are analysed,the principal questionsunder discussion is concerning with the total amount,the composition and theantiquitic taxa,such as Magnoliales,Annonales,Ranunculales,Hamamelidales andthe orders of Amentiflorae,etc.And then,the discussed question falls on therelationship between the floras of the ancient lands and the Cathaysian flora.An interest and valuable existing State of affair has shown,that although theAustralian and the Antarctic landmasses was broke away from the mainland ofGongwana at the late Jurassic,but more than 40% of genera (998) are coexistingin Cathaysia and Australia; and in the proper order,a large amount of generaare found between the Cathaysia and India、Tropical Asia、north America、south America and Africa also.Thus it can be seen that the flowering plantswould be originate at the dawn of Triassic or Mesozoic,in other word,it wasoriginated before the breakdown of the unionized Pangaea,Such assessment isproved by the (?)ossils and the survived flowering plants.Following the driftinglandmasses,the flowering plants of all the continents are developed continuously along with the new environment.Lastly,a suggestion is given,that the Cathaysian flora is originated locally,since there are numerous primary taxa survived here which are not found fromother continents,and all the remaining landmasses either covered by the gra-cial or by the sea transgression,or by the droughty climate throughout theMesozoic Period,it is imposible to nurse the flowering plants,only the stabilized Cathaysia will become the cradle of the primary spermatophytes as well asof the flowering plants.

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    Cited: Baidu(78)
    Carbon Sequestration Potential of Extensive Green Roofs
    CHEN Aikui; LU Jian;YUAN Jiangang;XU Yaxing;YANG Zhongyi
       2015, 54 (1): 89-95.  
    Abstract480)      PDF (1998KB)(364)      
    Green roofs, an increasingly visible component of urban environments, are becoming increasingly popular in many countries and have attracted much attention in China. The interest for green roofs has been related to their benefit as the crucial determinants of energy flux and of buildings water retention, so as to reduce stormwater runoff volumes and peak flows, mitigate effect of urban heat island and also provide urban habitats to improve urban biodiversity. However, there is rare research focusing on its carbon sequestration potential and the mitigation of climate change. In present study, two experiments were conducted on 10 green roofs with the objective of evaluating carbon accumulation potential of green roofs and the factors that affect green roof carbon storage. In the chamber experiment, a green roof was able to absorb CO2 as high as 0.46 g per m2 in one hour, and CO2 concentration declined as much as 162×10-6 over 5 minutes. Mean decrease of CO2 concentration and CO2 exchange rate in the chamber over the measurement period were 77.8×10-6 and-0.24 g·m-2·h-1, respectively. However, there was a high degree of variability because the photosynthesis rate of green roof plant greatly is dependent on light intensity and temperature, which change from time to time. Decrease of CO2 concentrations ranged from 23.50×10-6 to 162.00×10-6, and CO2 exchange rates ranged from-0.06 to-0.46 g·m-2·h-1 in the chamber. In the aboveground harvest experiment, data of the carbon reserve investigations showed that these green roofs stored an average of 92.55 g·m-2in aboveground biomass with also a wide variability(from 39.47 to 138.41 g·m-2), depended on the harvested biomass and carbon content of the biomass collected from the studied green roofs. In addition, it is notable that a significant correlation (R2=0.93) was observed between plant carbon content and substrate depth, while the correlations between substrate nutrient variables and carbon content was not statistically significant. Overall, the experimental results suggested that green roof can reduce the CO2 concentration in surrounding environment by absorbing CO2 in the daytime and act as a small carbon sink in urban area. It is likely that substrate depth may have big impacts on green roof carbon sequestration potential. Additional sophisticated research should be needed to evaluate the factors that contribute to the carbon sequestration potential of green roofs.
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    Effects of Anthraquinones Extracted from Rheum officinale Baill on Prevention of High Temperature of Macrobrachium rosenbergii
    LIU Bo;XIE Jun;GE Xianping;HE Yijing;XU Pao;;ZHOU Qunlan;PAN Liangkun;CHEN Ruli
       2009, 48 (6): 109-114.  
    Abstract1630)      PDF (715KB)(145)      

    In order to research the effects of anthraquinones extracte from Rheum officinale Baill on prevention of high temperature of Macrobrachium rosenbergii, Macrobrachium rosenbergii were divided into five groups randomly. The controls were fed with basal diet, the treated groups were fed with basal diet supplemented with 0.05%, 0.10%, 0.200%, 0.40% anthraquinones extracte for 8 weeks, respectively. After that, shrimp were stressed by high temperature at 35 ℃ for 48 hours continuously. Then the growth and the changes of nitrogen oxide, lysozyme, glucose, triglyceride and cholesterol and in haemolymph before and after the stress were investigated. The results showed that 0.10% dose group significantly increased weight gains and reduced feed conversion rate, and 0.40% dose group significantly increased haemolymph lysozymes contents before the stress. After the stress, 0.10% and 0.20% dose groups were relatively higher in haemolymph lysozymes and nitrogen oxides contents than those of the control. Stress also caused mortality in all groups of which 0.10%~0.20% dose groups were less than 30%, but the control was about 60%. It is concluded that ingestion of 0.10%~0.20% dose of anthraquinones extracte could help prevent negative effects of stress and improve shrimp growth.

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    Cited: Baidu(35)
    The Definition of Daily Mean Temperature Extremes over China and its Trend
    HUANG Danqing;QIAN Yongfu
       2008, 47 (3): 112-116.  
    Abstract2000)      PDF (1471KB)(156)      
    By use of the 1961-2005 daily mean temperature station data over China and the cumulative frequency distribution(CFD), the extremely high (low) temperature thresholds on four different time scales, day, pentad, month and season, are defined by the 90th (10th) percentiles of the CFD. It is found that the threshold on day scale (day threshold for short) contains systematic weather turbulences and, therefore, is not smooth enough. For this reason, the lowpass filtration is used to elide the wave less than eight days.Finally,a more reasonable day threshold is obtained to define temperature extremes.The results show that, for the warm (equal to and greater than the high temperature threshold) extremes, the trends of extreme days increase more remarkably in the south of 30°N than in the north with the smaller trend in the west of Inner Mongolia and the greater trend in the south of Yunnan and Hainan Province.Contrarily, for the cold (equal to and less than the low temperature threshold) extremes,the obvious regions with extreme days are in Northeast and North China and Tibetan Plateau. Both cold and warm extremes show increasing trends in average intensity in Southwest China and decreasing trends in Northeast China. The regions located in the south of 25°N are the obvious areas both in warm and cold extremes.
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    Cited: Baidu(35)
    New Kamenev-Type Oscillation Criteria for Second-Order Nonlinear Dynamic Equations on Time Scales
    QIU Yangcong;WANG Qiru
       2013, 52 (6): 26-29.  
    Abstract507)      PDF (1003KB)(277)      
    By using functions of the form H(t,s,t0) and a generalized Riccati transformation technique, new Kamenevtype oscillation criteria are established for second-order nonlinear dynamic equations on time scales of the form (p(t)ψ(x(t))xΔ(t))Δ+f(t,x(σ(t)))=0
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    Cited: Baidu(34)
    On Propagation of Electromagnetic Waves in Cylindrical Waveguides with Imperfectly Conducting Walls
    LIN Qionggui
       2010, 49 (3): 28-33.  
    Abstract1297)      PDF (1198KB)(122)      

    The perturbative method for calculating the effect of imperfectly conducting walls on the propagation of electromagnetic waves in cylindrical waveguides is reformulated. The equation for calculating the corrected eigenvalues is obtained in a quite different form. In comparison with the previous result, it is physically more transparent, formally simpler and more compact, and more convenient for practical calculations. 〖JP2〗Special cases overlooked previously are discussed. Results on the coaxial line are presented.〖JP〗

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    Cited: Baidu(20)
    Removal of Nitrogen from Water Bodies by Canna Floating Bed in Different Seasons
    SUN Lianpeng;LIU Yang;FENG Chen;WANG Zhuochao;JIN Hui
       2008, 47 (2): 127-130.  
    Abstract1982)      PDF (1295KB)(205)      

    Canna was planted in the eutrophication water with the technology of soilless culture in a polymethyl flume, and nitrogen was removed by the effection of plants absorbing and sorption, cooperated with bacteria. The experimental results show that nitrogen can be removed more by the canna floating bed in spring than that in autumn. The removal rate of total nitrogen was about 58.4% within five days, and the removal rate of NH+4-N was 100% within two days in spring. The removal rate of total nitrogen was about 50.4% within five days, and the removal rate of NH+4-N was 100% within four days in autumn. The removal rule is the same for different seasons.The experimental result is important to the floating bed operating in the whole year.

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    Cited: Baidu(18)
    The Graceful Graphs on Several Kinds of Union Graphs
    WEI Lixia;ZHANG Kunlong
       2008, 47 (3): 10-13.  
    Abstract1980)      PDF (792KB)(129)      
    To study the gracefulness of unconnected union graphs,several kinds of unconnected union graphs are given and the following results are obtained:for arbitrary positive integer n,m,let 's be the greatest integer not greater than n/2,Pn be a path with n vertex,St(m)be a star tree with m+1 vertex,graph An be the join graph of complement of P2 and Pn ,then for n≥2,the union of A2n and arbitrary a graceful graph with n-1 edges is a graceful graph;for n≥5,m≥s+2,the union of An and star tree St(m) is a graceful graph,therefore the union of An and star tree St(n) is a graceful grap;for n≥5,the union of An and arbitrary path Pn is a (n-s)graceful graph.
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    Cited: Baidu(17)
    Outline of Spermatophyta Classification
    Zhang Hongta
       1986, 25 (1): 1-13.  
    Abstract8)      PDF (928KB)(11)      

    The ovules of Spermatophytes are derived from the Rhynia-like telome andthe fertil(?)-sporophyll respectively,from them five types of seeds and fruits,i.e.Ginkgoales-type,Cordaites-Bennettites-type,Cycadales-Angiosperm-type,Taxales-Gnetales-type and Coniferae-type are developed.The matured fertilized embryo-sacs of Ginkgo,Cycas,Taxus and Podocarpus are not simple seeds,since thecollar rim of Ginkgo,and the flesh cups of Taxus and Podocarpus are equivalentto the carpels as an effective protect tissue,they are primary types of fruits, which are originated from different ways in the early phylogeny,and differedfrom that of flowering plants;additionally,Gnetum is a well known Chlamvdo-sperm with double-fertilization and without archegonium.Only the Coniferaeis a real representive of Gymnosperm.In this paper,the traditional classification of Spermatophytes is rejected.Allthe Spermatophytes including various Pteridosperm.are divided into the follow-ing subdivisions,they are Pteridospermophytina,Glossopteridophytina,Conifero-phytina,Ginkgoophytina,Cycadophytina,Caytoniophytina,Sinodictiophytina,Taxophytina,Chlamydospermophytina and Phanerogamophytina.To the last sub-division,Phanerogamophytina,a new system is given also.

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    Cited: Baidu(17)
    Research Progress on Supercapacitor in Hybrid Electric Vehicle
    XIONG Qi, TANG Dong-han ​
    Acta Scientiarum Naturalium Universitatis Sunyatseni    2003, 42 (S1): 130-133.  
    Abstract4)      PDF (485KB)(0)      
    Due to severe energy shortage and environment pollution, the idea of the hybrid electric vehicle (HEV) has been put forward since 1960s. The hybrid electric vehicles have the potential to increase fuel economy and decrease exhaust emissions. In recent years, in these HEV’ s system larger batteries are used to be proof against frequent pulse power of a starter motor and the rapid braking energy recovery, but supercapacitors (EDLC) is the best choice. In this paper, introduce to the differences between supercapacitors and batteries, conventional capacitor, and supercapacitors and HEV market prospect. 
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    Cited: Baidu(17)
    An Analysis of The Tendency of Erosion and Sedimentation on Foreshore and Channels of Lingding Estuary in Past Fifty Years
    WEN Ping~, LIU Pei-ran~, LEI Ya-ping~, REN Jie~, WU Chao-yu~
    Acta Scientiarum Naturalium Universitatis Sunyatseni    2003, 42 (S2): 240-243.  
    Abstract1)      PDF (159KB)(0)      
    Lingding Bay is a supreme complex estuarine system of the Pearl River mouth. The tendency of change on foreshore and channels has a notable influence on flood control of the Pearl River Delta and maintenance of waterway and renovation of estuary and exploitation of beach land resource. In this papers, changes of erosion and sedimentation are analysed about foreshore and channels of Lingding Bay in past fifty years by using marine charts of 1953 and 1964 and 1974 and 1989 and 1998. The results showed that sedimentation of Lingding estuary is a inevitable tendency and that whether water surface area or cubage decreases. But changes are not same for different depth of foreshore and channels. Its characteristic shows that foreshores is shallower and deep channels is deeper. In the last, the cause of formation for changes of foreshore and channels of Lingding estuary are analyzed. 
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    Cited: Baidu(16)
    Resources Status and Conservation Strategy of Ancient and Famous Trees in Zhuhai City,Guangdong Province
    TIAN Guang-hong~, HUANG Dong~, LIANG Jie-ming~, QIN Yu-zhong~
    Acta Scientiarum Naturalium Universitatis Sunyatseni    2003, 42 (S2): 203-209.  
    Abstract2)      PDF (234KB)(1)      
     Taking "The national technique standard of ancient and famous timber survey and setting up archives" as a scientific guidance, the number, tree-age, species, distribution and developing status of the ancient and famous timbers in Zhuhai City is overall investigated, meanwhile which also involved their resources store, utilization value, growth characters and survive crisis, etc. Has being aimed at the present question of ancient and famous timbers in Zhuhai City, the authors put up some new strategies about government guidance, exploitation principle, conservation technique and manager and bankroll, etc., which is with an important significant on developing the study of ancient and famous timbers, and developing urban tour planning and urban garden construction, etc.
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    Cited: Baidu(16)
    Research on the Load Limit Method for Sub-health Highway Concrete Beam Bridge
    LIU Airong;ZHANG Junping;YU Qicai;WU Gang
       2009, 48 (5): 42-46.  
    Abstract1470)      PDF (654KB)(151)      
    In order to make use of the loadcarrying capacity reasonably and moderately, the concept of serviceability bearing capacity is introduced in this paper. Based on the reliability analysis method, combing the result of appearance investment of existing highway subhealth bridge with load test and FE analysis, further, consider random factors such as carrying load and corrosion of reinforcement, take the crack width of concrete beam as generalized resistance force, the reliability analysis method of the serviceability capacity of subhealth highway concrete beam bridge is discussed, and the corresponding vehicular load limit method is put forward. The research result of this paper can be used to provide the academic reference for reasonable and scientific usage of subhealth highway bridges.
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    Cited: Baidu(16)
    Advances of the Studies on the Soil Protozoa
    CHEN Su-fang, XU Run-lin
    Acta Scientiarum Naturalium Universitatis Sunyatseni    2003, 42 (S1): 187-194.  
    Abstract1)      PDF (921KB)(0)      
     Based on the references reported, the methodologies, zoogeography, ecology and environmental biology on the soil protozoan studies have been reviewed in the paper. It shows that as an important component of biosphere, the soil protozoan plays the roles in the energy flow and material cycles on the earth, which can not subtitled by the other organisms. Meanwhile, the soil protozoan shows special zoogeographic patterns in distributions. The species composition of the soil protozoa is significant in the biodiversities on the earth. The characters of the soil protozoan in biology and ecology can be used to the practices widely. 
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    Cited: Baidu(15)
    Effects of the Herbicide Sulfometuron-methyl Killing Mikania micrantha and Their Influence on Plant Diversity
    WANG Yong-jun, LIAO Wen-bo, ZAN Qi-jie, WANG Bo-sun, WANG Zhang-jiu, GUO Hui-ru​
    Acta Scientiarum Naturalium Universitatis Sunyatseni    2003, 42 (S1): 180-186.  
    Abstract3)      PDF (689KB)(0)      
    Three kinds of environment such as "Sloping field, bottomland and swampland" badly covered by Mikania micrantha H.B.K. in Neilingding iSland of Guangdong province was divided into 15 plots with 10 m x 10 m each and were used to be tested the effects of herbicide sulfometuron-methy (concentration 0.0005- 0.5 g/m2) killing Mikania micrantha and its influence on the plant diversity. The observation results lasting one year was showed: (1) when the herbicide concentration is 0.01 -0.1 g/m2, it is with a well killing effect on Mikania micrantha; (2) This herbicide is almost no influence on the vine plants, with faintness influence on the herbaceous plants and lesser influence on the woody plants besides several sensitivity plants contained latex e. g. Boehmeria nivea (L.) Gaud., etc.; and (3) Comparing with before using herbicide and after using herbicide, the species diversity of plots is renew very-well, and in the whole the species diversity is increased obviouSly after using herbicide.
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    Cited: Baidu(15)
    Synthesis and Physical Chemistry Properties of Acidic 1-Butyl-3-Methylimidazolium Hydrosulfate Ionic Liquid
    WANG Xiaodan;;WU Wenyuan;TU Ganfeng;JIANG Kaixi;
       2009, 48 (6): 69-72.  
    Abstract1718)      PDF (450KB)(120)      
    1-butyl-3-methylimidazolium hydrosulfate([BMIM]HSO4) was synthesized with N-methylimidazolium and characterized. Some physical chemistry properties concerned, such as density, surface tension, viscosity, and electrical conductivity, are investigated and solvent performance is also studied. It is discovered from the experiments that this kind of ionic liquid has comparative electrical conductivity with familiar ionic liquids and the electrical conductivity follows the Arrhenius equation. Density, surface tension as well as viscosity of the ionic liquid decrease with increase of temperature. In addition, the ionic liquid is soluble in most conventional solvents and metal oxides have some solubility in it, which lays the foundation of direct electrolysis of metal oxides in ionic liquids.
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    Cited: Baidu(14)
    Network Pharmacology Study of Compound Xueshuantong Capsule Based on the Targets Related to Blood Circulation and Hemostasis
    LIU Zhongzheng;LIANG Jieping;NIE Yichu;LIU Hong;XIE Chengshi;CHENG Guohua;SU Weiwei
       2013, 52 (2): 97-100.  
    Abstract833)      PDF (1339KB)(463)      
    Network pharmacology based on the computational molecular docking was used to study interaction of chemical composition of Compound Xueshuantong Capsule to the targets related to blood circulation and hemostasis. A compound-target interaction network diagram was generated. The results showed that the chemical compounds of Compound Xueshuantong Capsule interacts with the multiple targets, such as ACE and PDE, revealing the multitargeted regulatory mechanism of Compound Xueshuantong Capsules in the treatment of retinal vein occlusion on molecular level.
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    Cited: Baidu(14)
    Anticoagulant Active Substances Extraction and Anti-Thrombin Activity Analysis of Several Species of Leeches
    ZHANG Bin;WANG Bo;GONG Yuan;YU Xiang;LV Junyi
       2012, 51 (4): 92-96.  
    Abstract765)      PDF (772KB)(439)      
    The anticoagulant activity in vitro of three different sample isolated from the leech, Hirudinaria manillensis with three different extracting methods was studied, and utilized the optimal extracting process, the anti-thrombin bioactivity of five species of leeches were analyzed, and compared the anti-thrombin bioactivity of three species of wild H. manillensis from different geographical distribution and two species of cultured H. manillensis reared with different diets. The results showed that among them, the extracts produced by acetone precipitation had the highest yield, and also displayed the stronger anticoagulant activity tested than others (P<0.05). The test displayed three species of non-bloodsucking leeches (Whitmania pigra, Whitmania acranulata and Whitmania laevis) had no or lower anti-thrombin activity, and the two species of blood-sucking leeches (H. manillensis and Hirudo nipponia) had higher anti-thrombin activity, and that the anti-thrombin activity of H. manillensis was higher than Hirudo nipponia significantly (P<0.01). There was no significant difference of inhibitory activity to thrombin between wild and cultured H. manillensis (P>0.05). In conclusion, the leech of  H. manillensis had high anti-thrombin bioactivity in vitro, and the artificial breeding had no adverse effect on its quality and anticoagulant activity.
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    Cited: Baidu(14)
    A Spatial Analysis of the Image of Tourism Destination--A Case Study on Ancient Water Towns in Southern Yangtze River
    JIANG Zhi-jie, WU Guo-qing, BAI Guang-run
    Acta Scientiarum Naturalium Universitatis Sunyatseni    2003, 42 (S2): 248-253.  
    Abstract1)      PDF (247KB)(0)      
     It first aims to further explore the regularity of the spatial of the image of tourism destination and second to benefit the sustainable development of Ancient Water Towns in the southern Yangtze River(China).The study,based on the content analysis of 180 samples of travelers. By using mental map and questionnaire survey,five components commonly found in these sketch maps:paths,nodes,edges,landmarks and districts. The framework of the mental map was found to be constituted by the main roads and bridges,together with the personality nodes, remarks and districts. The actual map is then compared,and recommendations for future tourism planning and designing of Ancient Water Towns in the southern Yangtze River are presented in concluding sections. 
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    Cited: Baidu(13)