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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.  
    Abstract13)      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(104)
    The Continental Drift and the Development of the Flowering Plants
    Chang Hang-ta
       1986, 25 (3): 4-14.  
    Abstract7)      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(80)
    The Fingerprint of Kouyanqing Granule
    GUAN Qianyi;HUANG Lin;PENG Wei;WANG Deqin;SU Weiwei
       2011, 50 (1): 115-118.  
    Abstract1238)      PDF (894KB)(113)      
    In this paper, the HPLC fingerprint of Kouyanqing Granule was established with Dikma PLATISIL ODS (250 mm×4.6 mm, 5 μm) column, acetonitrile and 0.1% (φ) formic acid as mobile phase, and the detection wavelength was 254 nm. 23 common peaks were selected as the fingerprint peaks. Seven of these common peaks were identified as chlorogenic acid, caffeic acid, luteolin-7-O-glucoside, harpagoside, cinnamic acid, ammonium glycyrrhetate and glycyrrhizic acid. The method established is selective, simple and reproducible, which can be used for the quality control of Kouyanqing Granule.
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    Cited: Baidu(62)
    Trends in All Kinds of Precipitation Events in China over the Past 40 Years
    MIN Shen;QIAN Yongfu
       2008, 47 (3): 105-111.  
    Abstract2299)      PDF (1761KB)(151)      
    Based on daily rainfall dataset of 542 stations in China during the period of 1960-2003, the trends in all kinds of precipitation events in China are briefly studied in this paper. The results show that.the increasing total precipitation amount is mainly caused by the rising extreme precipitation (EP), and the reducing sprinkle frequency is the major reasons of the decreasing rain days. A decrease in rain days is observed in most regions of China, and EP events still have increased trends in many areas at the same time, so the lessening rain days could not reduce the possibility of EP. The trend of the sprinkle frequency is the most obvious change in all kinds of precipitation events, and declining is the main trend throughout most parts of China. A significant increase in EP events is observed in western China in all seasons. The EP events have decreased in the Yangtze River and southern China in autumn, but increased in the other three seasons. In northern and northeastern China, EP events show an increase in winter and a half increase in the other seasons. The ratio of EP amount to total precipitation amount is generally increasing in most areas of China,suggesting that the precipitation event has an obvious trend of extremeness.
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    Cited: Baidu(50)
    The Definition of Daily Mean Temperature Extremes over China and its Trend
    HUANG Danqing;QIAN Yongfu
       2008, 47 (3): 112-116.  
    Abstract2009)      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(43)
    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.  
    Abstract1636)      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(37)
    Carbon Sequestration Potential of Extensive Green Roofs
    CHEN Aikui; LU Jian;YUAN Jiangang;XU Yaxing;YANG Zhongyi
       2015, 54 (1): 89-95.  
    Abstract495)      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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    Cited: Baidu(36)
    New Kamenev-Type Oscillation Criteria for Second-Order Nonlinear Dynamic Equations on Time Scales
    QIU Yangcong;WANG Qiru
       2013, 52 (6): 26-29.  
    Abstract517)      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)
    Isolation and Metabolite Bioactivities of Mangrove Fungal Endophytes
    DENG Zujun;;CAO Lixiang;ZHOU Shining
       2010, 49 (2): 100-104.  
    Abstract1546)      PDF (1296KB)(118)      
    Eightyfive endophytic fungi strains were isolated from eight kinds of mangrove plants. The main taxa are mycelia sterilia, Aureobasidium〖WTBZ〗 spp. and Gloeosporiumspp., accounting for 18.0%,14.6% of the total strains respectively. Their metabolite bioactivities were primarily studied. Results indicated that the extract of hypha and fermentation liquor have good inhibition activity to test bacteria,the active strains proportion to Escherichia coli is 22.4%,21.2% respectively, to Staphylococcus aureus is 12.9%,14.1%, to Bacillus subtilus is 20.0%,36.5%;fermentation liquor also has good inhibition activity to Candida albicans,Saccharomyces cerevisiae,Curvularia lunata,accounting for 25.9%,23.5%,28.2% of the total strains respectively,but their hypha extract has no inhibition activity to test fungi. Metabolites of eight strains (occupying 9.0% of the total strains) can inhibit germination and bud growth of wheat and have herbicidal activity. Metabolites of fourteen strains(occupying 16.5% of the total strains) can inhibit antibioticresistance Ecoli by wholecell targeted screening model. These results showed mangrove fungal endophytes would be a rich resource pool for new drug and herbicide.

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    Cited: Baidu(24)
    The Distributive Character and Pollution Assessment of Heavy Metals in Urban Soil of Guangzhou
    ZHUO Wenshan;TANG Jianfeng ;GUAN Dongsheng
       2009, 48 (4): 47-51.  
    Abstract1636)      PDF (1231KB)(191)      
    The concentrations of and forms Ni,Cr,Pb,Zn and Cu in different functional zones are studied,the relationship between heavy metals and soil characteristics is analyzed.The results indicated that the surface soil was contaminated by heavy metals, especially in old industry and new residence zones.The concentration of Pb is high and should be paid more attention. Residual form were the major fraction of Ni,Cu and Cr, but the major form of Zn and Pb is Fe-Mn oxide form.
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    Cited: Baidu(23)
    On Propagation of Electromagnetic Waves in Cylindrical Waveguides with Imperfectly Conducting Walls
    LIN Qionggui
       2010, 49 (3): 28-33.  
    Abstract1305)      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)
    Study on Building Vibration Caused by Rail Transit
    XIE Weiping;CHANG Liang;GU Qian
       2009, 48 (1): 103-109.  
    Abstract1766)      PDF (1892KB)(114)      
    Many investigations have been carried out by many researchers in order to evaluate the effect of trafficcaused vibration on environment. However, they mainly focused on traffic-caused ground vibration, few of them aimed at building vibration. Based on field measurement results acquired by authors and others, the study on evaluation method of vibration in the room of residential buildings was carried out and some deficiencies of previous researches were pointed out. Then, the building vibration caused by rail transit was analyzed by employing FEM. The effects of building natural frequency and building height on the vibration of each floor were discussed. Comparing numerical results with measurement results, some phenomenon observed in field measurement were explained reasonably, and it can also be concluded that the maximum vibration response may occur on a certain middlefloor and the enlarged vibration region may exist in front of a building due to the mutual superimpose of the incident and reflected waves.
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    Cited: Baidu(19)
    Solving Nonlinear Equations Based on Improved Genetic Algorithm
    YAN Lewei;CHEN Shuhui
       2011, 50 (1): 9-13.  
    Abstract1481)      PDF (1252KB)(135)      
    Some methods such as population isolation mechanism, optimum reserved strategy, arithmetic crossover, adaptive random mutation and heterogeneous strategy are used to improve genetic algorithm. Besides the advantage that the optimal solution can be found only by the value of objective function, the local searching capability is enhanced in this improve genetic algorithm. This algorithm is applied to solve nonlinear equations. Numerical examples demonstrated that this algorithm can solve the optimization problem which has nonlinear equality constraint. Furthermore, the heterogeneous strategy speeds up the process of convergence and raises the convergence probability of global optimal solution.
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    Cited: Baidu(19)
    The Graceful Graphs on Several Kinds of Union Graphs
    WEI Lixia;ZHANG Kunlong
       2008, 47 (3): 10-13.  
    Abstract1983)      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(18)
    Research of Actuality and Characters of Indoor Air Pollution in Guangdong Province
    ZHANG Shujuan;SU Zhifeng;LIN Zejian;XU Peiyuan;HUANG Yaotang;XIE Zizhao
       2011, 50 (2): 139-141.  
    Abstract1301)      PDF (992KB)(154)      

    In order to study indoor air pollution, eight air pollutantsformaldehyde, benzene, methylbenzene,ethylbenzene,dimethylbenzen, TVOC, Rn and NH3 collected from 427 apartments in Guangdong Province were tested according to the indoor air quality standards(GB / T 18883-2002). The results indicate that concentrations of formaldehyde, benzene, methylbenzene, TVOC, Rn and NH3 exceed 43.83%, 3.35%, 31.51%, 19.18%, 43.59%, and 0.57% of the standards, respectively. Indoor air is mainly polluted by organic pollutants. VOCs contain many complex components. Correlation coefficient between dimethylbenzen and other benzene series is above 0.60, much higher than that between benzene and other benzene series (<0.30).

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    Cited: Baidu(18)
    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.  
    Abstract1989)      PDF (1295KB)(210)      

    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)
    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(18)
    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(18)
    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.  
    Abstract4)      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(17)
    Research Progress on Supercapacitor in Hybrid Electric Vehicle
    XIONG Qi, TANG Dong-han ​
    Acta Scientiarum Naturalium Universitatis Sunyatseni    2003, 42 (S1): 130-133.  
    Abstract17)      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)