检索结果-南通市图书馆

Studies on growth rate and grazing mortality rate by microzooplankton of size-fractionated phytoplankton in spring and summer in the Jiaozhou Bay,China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2005年第2期24卷 85-101页

作者： ZHANGLiyong sunjun LIUDongyan YUZishan KeyLaboratoryofMarineEcology＆EnvironmentalScience ChineseAcademyofSciencesQingdao266071China／／GraduateSchooloftheChineseAcademyofSciencesBeijing100039China KeyLaboratoryofMarineEcology＆EnvironmentalScience ChineseAcademyofSciencesQingdao266071China CollegeofMarineLifeScience OceanUniversityofChinaQingdao266003China

Dilution experiments were performed to examine the growth rate and grazing mortality rate of size-fractionated phytoplankton at three typical stations, inside and outside the bay, in the spring and summer of 2003 in the Jiaozhou Bay, China. In spring, the phytoplankton community structure was similar among the three stations, and was mainly composed of nanophytoplankton, such as, Skeletonema costatum and Cylindrotheca closterium. The structure became significantly different for the three stations in summer, when the dominant species at Stas A, B and C were Chaetoceros curvisetus, Pseudo-nitzschia delicatissima, C. affinis, C. debilis, Coscinodiscus oculus-iridis and Paralia sulcata respectively. Tintinnopsis beroidea and T. tsingtaoensis were the dominant species in spring, whereas the microzooplankton was apparently dominated by Strombidium sp. in summer. Pico- and nanophytoplankton had a relatively greater growth rate than microzooplankton both in spring and summer. The growth rate and grazing mortality rate were 0.18~0.44 and 0.12~1.47 d-1 for the total phytoplankton and 0.20~0.55 and 0.21~0.37 d-1 for nanophytoplankton in spring respectively. In summer, the growth rate and grazing mortality rate were 0.38~0.71 and 0.27~0.60 d-1 for the total phytoplankton and 0.11~1.18 and 0.41~0.72 d-1 for nano- and microphytoplankton respectively. The carbon flux consumed by microzooplankton per day was 7.68~39.81 mg/m3 in spring and 12.03~138.22 mg/m3 in summer respectively. Microzooplankton ingested 17.56%~92.19% of the phytoplankton standing stocks and 31.77%~467.88% of the potential primary productivity in spring; in contrast, they ingested 34.60%~83.04% of the phytoplankton standing stocks and 71.28%~98.80% of the potential primary productivity in summer. Pico- and nanophytoplankton appeared to have relatively greater rates of growth and grazing mortality than microphytoplankton during the experimental period. The grazing rate of microzooplankton in summer was a litt

关键词： microzooplankton phytoplankton selective grazing carbon to chlorophyll-a ratio grazing pressure Jiaozhou Bay

The effects of spring-neap tide on the phytoplankton community development in the Jiaozhou Bay, China

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2004年第4期23卷 687-697页

作者： LIUDongyan sunjun LIUZhe CHENHongtao WEIHao ZHANGJing MarineEcosystemDynamicLaboratory OceanUniversityofChinaQingdao266003China KeyLaboratoryofMarineEcology＆EnvironmentalScience InstituteofOceanologyChineseAcademyofSciencesQingdao266071China InstituteofPhysicalOceanography OceanUniversityofChinaQingdao266003China CollegeofChemistryandChemicalEngineering OceanUniversityofChinaQingdao266003China CollegeofChemistryandChemicalEngineering OceanUniversityofChinaQingdao266003China／／StateKeyLaboratoryofEstuarineandCoastalResearchEastChinaNormalUniversityShanghai200062China

The development of the phytoplankton community was studied in the Jiaozhou Bay during the spring to neap tide in August2001, through three cruises and a 15 d continuous observation. This investigation indicates that diatom cell abundance increasedsharply following the end of a spring tide, from 9 cells/cm3 to a peak of 94 cells/cm3. The dominant species composition andabundance show a quick species sequence from spring to neap tide, and the dominant species at the start phase is Skeletomenacostatum, then changes to Chaetoceros curvisetus, finally it changes to Eucampia zodiacus. Silicate concentration increasesduring spring tide, as a result of nutrient replenishment from the watersediment interface, its initial average concentration inneap tide is 1.39 mmol/dm3 and reached the peak average concentration of 8.40 mmol/dm3 in spring tide. But the nitrogenconcentration dropped due to dilution by the low nitrogen seawater from the Huanghai Sea, its initial average concentration inneap tide is 67 mmol/dm3 and decreased to the average concentration of 54 mmol/dm3 in spring tide. The degree of siliconlimitation was decreased and phytoplankton, especially diatoms, responds immediately after nutrient replenishment in thewater column. Skeletonmea costatum, as one of the dominant species in the Jiaozhou Bay, shows a quicker response tonutrient availability than Eucampia zodiacus and Chaetoceros curvisetus. It is proposed that dominant species compositionand water column stability synchronously determine the development of phytoplankton summer blooms in the Jiaozhou bay.

关键词： phytoplankton hydrodynamics nutrients spring to neap tide Jiaozhou Bay coastal waters

Water-Soluble Rare Earth Elements in Some Soils of China

在线全文

学校读者我要写书评

暂无评论

Pedosphere 1997年第1期7卷 25-30页

作者： ZHUJIANGUO sunjun 等 LMCP，InstituteofSoilScienec AcademiaSinicaNanjing210008（China） LMCP，InstituteofSoilScienec Academi

Water-soluble rare earth elements (WSREEs) of four typical soil profiles in China were determined by using a high-resolution inductively coupled plasma mass spectrometer. Results showed that the contents of WSREEs decreased from upper layer to lower layer of soils in the southern part of China with a high rainfall and low pH but increased for soils in the northern part of China with a low rainfall and relatively higher pH. Contents of WSREEs in soils were lower than 100 μg kg-1 in most casest and varied greatly with both different soils and different layers of the same profile. The highest content was 2816.3 μg kg-1 but the lowest was 17.6 μg kg-1 only. The content of individual rare earth iement (REE) in the soil solution also varied greatly with the highest one ranging from 8.4 to 1373 μg kg-1 for Ce and the lowest one from 0.05to 4.48 μg kg-1 for Lu. The sum of WSREEs in the first soil layers ranged from 121.5 to 345.6 μg *** variations existed among ratios of REEs extracted with water to the total REEs of soils, ranging from 0.02×10-3 to 13.2×10-3. But as the upper layer was considered, the ratio showed only a small difference,ranging from 0.79×10-3 to 1.69×10-3.

关键词： rare earth element soil profiles ICP-MS

Plasma Nitriding of Austenitic Stainless Steel with Severe Surface Deformation Layer

在线全文

学校读者我要写书评

暂无评论

材料热处理学报 2004年第5期25卷 425-427页

作者： JIShi-jun GAOYu-zhou WANGLiang sunjun-cai HEIZu-kun InstituteofMetalandTechnology DalianMaritimeUniversity

The dc glow discharge plasma nitriding of austenite stainless steel with severe surface deformation layer is used to produce much thicker surface modified layer. This kind of layers has useful properties such as a high surface hardness of about 1500 Hv 0.1 and high resistance to frictional wear. This paper presents the structures and properties of low temperature plasma nitrided austenitic stainless steel with severe surface deformation layer.

关键词：等离子渗氮奥氏体不锈钢变形

Reaction of Oilseed Rape Cultivars to Sclerotinia Stem Rot in Field Environ- ments

在线全文

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2005年第4期4卷 273-280页

作者： sunjun-ming HANFen-xia MalgorzataJedryczka KeyLaboratoryofCropGeneticsandBreedingofMinistryofAgriculture~InstituteofCropSciences ChineseAcademyofAgriculturalSciencesBeijing100081P.R.China InstituteofPlantGenetics PolishAcademyofSciences60-479PoznariPoland

Sclerotinia sclerotiorum (Lib.) de Bary, as an ubiquitous phytopathogenic Ascomycete fungus capable of infecting a wide range of plants, has increased in importance for oilseed rape production worldwide in recent years. The objective of this research was to determine the effectiveness of two measurements of disease rating in predicting the field reaction of cultivars to sclerotinia stem rot. One hundred and ten cultivars or lines of oilseed rape were repeatedly evaluated the disease severity index (DSI) and lesion length for their resistance to nine isolates of S. sclerotiorum in two field stations. There were greatly significant differences between two stations, among isolates, among population of cultivars for the disease severity index and lesion length, and also significant station×isolate interaction for lesion length and population×isolate interactions for DSI and lesion length, but interactions of station×isolate for DSI were not significant. Cultivars such as Pomorzanin and Lisek consistently had the lowest disease severity ratings in the field tests. However, most of cultivars were susceptible to sclerotinia stem rot in the field test. A positive correlation between the mean DSI and lesion length was found for both isolates (Sc23 and B1). The correlations ranged from 0.23 to 0.83 at various plots, with nine of the twelve correlations significant. The correlations for disease caused by different fungal isolates were statistically significant difference. These correlations ranged from -0.44 to 0.90, with nine of the thirty-two correlations significant. It indicated that resistance to some isolates was significantly correlated and selection of some varieties for resistance to one isolate appeared to improve resistance to other isolates.

关键词： Oilseed rape (Brassica napus) Sclerotinia sclerotiorum Pathogenicity Field environments

Preliminary Study on the Responses of Three Marine Algae,Ulva pertusa(Chlorophyta),Gelidium amansii(Rhodophyta)and Sargassum enerve(Phaeophyta),to Nitrogen Source and Its Availability

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2004年第1期3卷 75-79页

作者： LIUDongyan AmyPickering sunjun CollegeofMarineLifeScience OceanUniversityofChinaQingdao266003P.R.China DepartmentofBiologicalandEnvironmentalEngineering CornellUniversityIthacaNY14850USA KeyLaboratoryofMarineEcology＆EnvironmentalScience InstituteofOceanologyChineseAcademyofSciencesQingdao266071P.R.China

An experiment was designed to select economically valuable macroalga species with high nutrient uptake rates. Such species cultured on a large scale could be a potential solution to eutrophication. Three macroalgae species, Ulva pertusa (Chlorophyta), Gelidium amansii (Rhodophyta) and Sargassum enerve (Phaeophyta), were chosen for the experiment because of their economic values and availability. Control and four nitrogen concentrations were achieved by adding NH + 4 and NO - 3. The results indicate that the fresh weights of all species increase faster than that of control after 5 d culture. The fresh weight of Ulva pertusa increases fastest among the 3 species. However, different species show different responses to nitrogen source and its availability. They also show the advantage of using NH + 4 than using NO - 3. U. pertusa grows best and shows higher capability of removing nitrogen at 200 μmol L -1 , but it has lower economical value. G. amansii has higher economical value but lower capability of removing nitrogen at 200 μmol L -1 . The capability of nitrogen assimilation of S. enerve is higher than that of G. amansii at 200 μmol L -1 , but the former’s increase of fresh weight is lower than those of other two species. Then present preliminary study demonstrates that it is possible to use macroalgae as biofilters and further development of this approach could provide biologically valuable information on the source, fate, and transport of N in marine ecosystems. Caution is needed should we extrapolate these findings to natural environments.

关键词： macroalgae nitrogen source eutrophication nutrient uptaking

Multi-Agent Network Intrusion Active Defense Model Based on Immune Theory

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2007年第1期12卷 167-171页

作者： LIU sunjun LI Tao WANG Diangang HU Xiaoqing XU Chun School of Computer Science Sichuan University Chengdu610065 Sichuan China

Inspired by the immune theory and multi-agent systems, an immune multi-agent active defense model for network intrusion is established. The concept of immune agent is introduced, and its running mechanism is established. The method, which uses antibody concentration to quantitatively describe the degree of intrusion danger, is presented. This model implements the multi-layer and distributed active defense mechanism for network intrusion. The experiment results show that this model is a good solution to the network security defense.

关键词： artificial immune system intrusion detection system multi-agent system network security

Detection of RAPD Markers Linked to Gene lx_1 in Soybeans

在线全文

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2004年第1期3卷 8-13页

作者： sunjun-ming WUShu-ming TAOWen-jing DINGAn-lin HANFen-xia JIAShi-rong InstituteofCropBreedingandCultivation ChineseAcademyofAgriculturalSciences／KeyLaboratoryofCropGeneticsandBreedingMinistryofAgricultureBeijing100081P.R.China BiotechnologyResearchInstitute ChineseAcademyofAgriculturalSciencesBeijing100081P.R.China

Near-isogenic lines of soybean lipoxygenase, which contain genes Lox, lx1, lx2, lx3, lx1.3, lx2.3,respectively, were used for polymorphic analysis by RAPD technique.520 10-mer-oligonucleotideprimers were screened, and thirteen primers showed polymorphism among near-isogenic *** were six primers showed special polymorphic bands among lines lx1 and lx1.3. Especially,primer S352 presented the stable results in which a 900 bp band was found in the lines lx1 andlx1.3, and primer S352900 was detected with F2 generation of cross 96P11×Century-1, indicatedprimer S352900 could be identified as a RAPD marker linked to gene lx1 in soybeans, the distanceof linkage was 7.6 cM.

关键词： Soybean(Glycine max) Lipoxygenase RAPD Marker

Anomaly Detection with Artificial Immune Network

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2007年第5期12卷 951-954页

作者： PENG Lingxi LI Tao LIU Xiaojie CHEN Yuefeng LIU Caiming LIU sunjun College of Computer Science Sichuan University Chengdu 610065 Sichuan China School of Information Guangdong Ocean University Zhanjiang 524025 Guangdong China

Inspired by the immune network theory, an adaptive anomaly detection paradigm based on artificial immune network, referred as APAI, is proposed. The implementation of the paradigm includes： initially, the first is to create the initial antibody network; then, through the learning of each training antigen, the antibody network is evolved and updated by the optimal antibodies. Finally, anomaly detection process is accomplished by majority vote of the k nearest neighbor antibodies in the network. The experiments used the famous Sonar Benchmark dataset in our study, which is taken from the UCI machine learning database. The obtained detection accuracy of APAI was 97.7%, which was very promising with regard to the other classification applications in the literature for this problem. In addition to its nonlinear classification properties, APAI possesses biological immune network properties such as clonal selection, immune network, and immune memory, which can be applied to pattern recognition, classification, and etc.

关键词： anomaly detection artificial immune network machine learning classification