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1.
Gan Shi-xin 《武汉大学学报:自然科学英文版》2003,8(4):1047-1050
L
r convergence and convergence in probability for weighted sums ofL
q-mixingale arrays have been discussed and the Marcinkiewicz type weak law of large numbers forL
q-mixingale arrays has been obtained.
Foundation item: Supported by the National Natural Science Foundation of China (10071058)
Biography: Gan Shi-xin (1939-), male, Professor, research direction; martingale theory, probability limiting theory and Banach space
geometry theory. 相似文献
2.
Li Xi Liu Yi Deng Feng |jiao Qu Song |sheng . College of Chemistry Molecular Sciences Wuhan University Wuhan Hubei China . College of Life Sciences Wuhan University Wuhan Hubei China . State Key Lab of Advanced Technology for Materials Synthesis Processi ng Wuhan University of Technology Wuhan Hubei China 《武汉大学学报:自然科学英文版》2003,8(1)
0 IntroductionSeleniumpresentsanutritionconundrumthroughitsdualstatusasanessentialandhighlytoxicnutrient.Fromearlyinthiscentury ,seleniumhasbeenknowntocausetoxicityinanimalsproducingconditions ,suchasblindstaggersandalkalidisease[1] .In 195 7,SchwardzandFoltz… 相似文献
3.
The purpose to this paper is to study the existence problem of solutions to the vector quasivariational inequality for vector-valued
functions inH-space.
Foundation item: Supported by the Science Research Foundation of Xianning Teacher’s College (No. K9911)
Biography: Mao Jian-feng (1960-), male, Lecturer, research direction: nonlinear functional analysis. 相似文献
4.
ZHANG Xu WU Feng WANG Beibei DENG Nansheng LUO Mingdao 《武汉大学学报:自然科学英文版》2007,12(3):535-540
The inclusion behavior of 4, 4' -Thiodiphenol (TDP), a typical bisphenol and endocrine disruptor, reacts with β-cyclodextrin (β-CD) in aqueous solutions has been investigated by means of UV absorption spectrum and quantum-chemical calculation with Gaussian 98 software. The results show that the inclusion behavior of TDP is quite different in acidic solutions (pH 5.9) from that in alkaline solutions (pH 10.0). This behavior difference is attributed to the different formula structures in aqueous solutions at acidic and alkaline pH values that are demonstrated by quantum- chemical modeling and calculation. TDP forms a 1 : 1 fl-CD inclusion complex in aqueous solutions. The equiiibrium constant K was calculated to be 553.49 L/mol at pH 5.9 and 1 318.20 L/mol at pH 10.0 respectively for the inclusion complex reaction by using the modified Benesi-Heldbrand equation. After inclusion TDP's structure is changed especially at the inclusion part with the bond order becoming larger, which results in inhibitive photodegradation during direct photooxidation and H2O2 assisted photooxidation. 相似文献
5.
Let {Xn, n≥1} be a martingale difference sequence and {a
nk
, 1⩽k⩽n,n⩾1} an array of constant real numbers. The limiting behavior of weighted partial sums ∑
k=1
n
a
nk
X
k
is investigated and some new results are obtained.
Foundation item: Supported by the National Natural Sciene Foundation of China (No. 10071058 and No. 10071019)
Biography: Gan Shi-xin (1939-), male, Prof lessor, research direction: martingale theory, probability limiting theory and
Banach space geometry theory. 相似文献
6.
The growth of Staphylococcus aureus under the action of six kinds of Schiff bases(A,B,C,D,E,F) was studied by means of microcalorimetry. Growth constant k and inhibition ratio I were calculated. Also,the antibacterial activity,the action characteristics and the structure-activity relationships of the compounds on S. aureus were analyzed. Results indicate that B,F show good antibacterial activity(IC50:293.6 mg · L-1 and 307.8 mg · L-1) ,D,E show moderate antibacterial activity(IC50:966.3 mg · L-1 and 1 126.7... 相似文献
7.
Biosorption of Cu(Ⅱ) and Pb(Ⅱ) by Auricularia polytricha 总被引:1,自引:0,他引:1
ZHANG Dan GAO Jianwei GAO Tingyan YING Yigao CHEN Hong 《武汉大学学报:自然科学英文版》2007,12(4):755-761
For searching biological material for heavy metal removal of waste-water, using macrofungus Auricularia polytricha as biosorbent for Cu^2+ and Pb^2+ removal was investigated. After shaking and biosorbing Cu^2+ and Pb^2+ in solution by biosorbents, the filtrates were tested by AAS and the adsorbed quantity of Cu^2+ and Pb^2+ was calculated. The biosorbents were effective in removal of Cu^2+ and Pb^2+ on the biosorbents that showed a high- est value around pH 5-6. The biosorption rate of Cu^2+ and Pb^2+ on A. polytricha biomass decreased with increasing the initial concentration of Cu^2+ and Pb^2+ in the medium. The biosorption of Cu^2+ and Pb^2+ on the biomasses follows pseudo-second order kinetics. The determined maximum biosorption capacities presented by the fungus biomass were 3.34 and 13.03 mg·g^-1 dry weight for Cu^2+ and Pb^2+, respectively by the biosorption equilibrium with Langmuir adsorption isotherm. According to the whole data analysis in each experiment of studying Cu^2+ and Pb^2+ biosorption including condition factors and adsorption isotherm, the adsorbed capacity of Pb^2+ by A. polytricha biomass was bigger than Cu^2+. The biosorption by A. polytricha was most effective when pH 5-6. The biosorbents are suitable for low Cu^2+ and Pb^2+ concentration waste-water, especially for Pb^2+ removal. 相似文献
8.
WangShao-wei ZhuQiu-ping YangYong 《武汉大学学报:自然科学英文版》2004,9(1):59-62
Echo canceller generally needs a double-talk detector which is used to keep the adaptive filter from diverging in the appearance of near-end speech. In this paper we adopt a new double-talk detection algorithm based on ι2 norm to detect the existence of near-end speech in an acoustic echo canceller. We analyze this algorithm from the point of view of functional analysis and point out that the proposed double-talk detection algorithm has the same performance as the classic one in a finite Banach space. The remarkable feature of this algorithm is its higher accuracy and better computation complexity. The fine properties of this algorithm are confirmed by computer simulation and the application in a multimedia communication system. 相似文献
9.
GAN Shixin CHEN Pingyan QIU Dehua 《武汉大学学报:自然科学英文版》2007,12(2):211-217
We give some theorems of strong law of large numbers and complete convergence for sequences of φ-mixing random variables. In particular, Wittmann's strong law of large numbers and Teicher's strong law of large nnumbers for independent random variables are generalized to the case of φ -minxing random variables. 相似文献
10.
GanShi-xin 《武汉大学学报:自然科学英文版》2004,9(1):13-17
This paper investigates some conditions which imply the strong laws of large numbers for Banach space valued random variable sequences. Some generalizations of the Marcinkiewicz- Zygmund theorem and the HoffmannJφrgensen and Pisier theorem are obtained. 相似文献
11.
ZHAO Yaqun YING Dinghai FENG Dengguo 《武汉大学学报:自然科学英文版》2007,12(1):185-188
This paper discusses the best affine approach (BAA) of multi-output m-valued logical functions. First, it gives the spectra of rate of accordance between multi-output m-valued logical functions and their affine functions, then analyzes the BAA of multi-output m-valued logical functions and finally gives the spectral characteristics of BAA of multi-output m-valued logical functions. 相似文献
12.
Gan Shi-xin 《武汉大学学报:自然科学英文版》2002,7(1):14-19
For weighted sums of the form
where {a
nj
, 1 ⩽j⩽k
n
↑∞,n⩾1} is a real constant array and {X
aj
, 1≤j≤k
n, n≥1} is a rowwise independent, zero mean, random element array in a real separable Banach space of typep, we establishL
r
convergence theorem and a general weak law of large numbers respectively, conversely, we characterize Banach spaces of typep in terms of convergence inr-th mean and probability for such weighted sums.
Foundation item: Supported by the National Natural Science Foundation of China (No. 10071058)
Biography: Gan Shi-xin (1939-), male, Professor, research direction: martingale theory, probability limiting theory and Banach
space geometry theory. 相似文献
13.
KOU Yue SHEN Derong YU Ge LI Dong NIE Tiezheng 《武汉大学学报:自然科学英文版》2007,12(5):830-834
Caching is an important technique to enhance the efficiency of query processing. Unfortunately, traditional caching mechanisms are not efficient for deep Web because of storage space and dynamic maintenance limitations. In this paper, we present on providing a cache mechanism based on Top-K data source (KDS-CM) instead of result records for deep Web query. By integrating techniques from IR and Top-K, a data reorganization strategy is presented to model KDS-CM. Also some measures about cache management and optimization are proposed to improve the performances of cache effectively. Experimental results show the benefits of KDS-CM in execution cost and dynamic maintenance when compared with various alternate strategies. 相似文献
14.
Effect of UV-B Radiation on Ingesting and Nutritional Selecting Behavior of Rotifer Brachionus urceus 总被引:3,自引:0,他引:3
FENG Lei TANG Xuexi WANG You XIAO Hiu MENG Xianghong CHEN Xiguang 《武汉大学学报:自然科学英文版》2007,12(2):361-366
Effect of UV-B radiation on ingesting and nutritional selecting behavior of the roifer Brachionus urceus on 5 species of microlgae were studied under controlled laboratory conditions. Restdts showed that enhanced UV-B radiation significantly inhibited ingesting of the rotifer B. urceus when it was fed with 5 species of micro-algae (p〈0.05). The ingesting selectivity rate varied with the UV-B radiation enhancement when it was fed with 5 species micro-algal mixture. Results indicated that the enhanced UV-B radiation could affect ingesting and nutritional selectivity of B. urceus. 相似文献
15.
WANG Qin JIANG Lin WEN Qibiao 《武汉大学学报:自然科学英文版》2007,12(3):529-534
The physical properties and chemical components of three oil samples extracted from Illicium verum Hook. f. by steam distillation (SD), solvent extraction (SE) and supercritical fluid extraction (SFE) were compared with one another and analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). The quality parameters of star anise essential oil from SFE were close to that of those came from SD and SE. Although the extraction yield of star anise by SFE (9.2 %) was close to the value from SE (9.3%), it was yet higher than that came from SD (8.2%). For sensory evaluation, however, three oils were significantly different. The odor and taste of the products from SFE and SE were generally more natural and vivid than that came from distilled oil. The volatile compound revealed that significant differences of the composition existed in the distilled oil and the oleoresins prepared by SFE and SE. 相似文献
16.
Ningsheng Qin Xuemei Shao Liya Jin Qingchun Wang Xide Zhu Zhenyu Wang Jinbao Li 《科学通报(英文版)》2003,48(22):2484-2488
Two tree ring-width chronologies of Sabina tibetica were developed based on cores sampled in Qumalai and Zhiduo, southern Qinghai Plateau. The response function analysis showed
that the chronologies were sensitive to temperature and precipitation from April to June in the plateau. Moisture index (MI)
was defined, reconstructed and extended back to AD 1550. The cross-validation method was used to check the stability of the
calibration equation, and the result indicated that the equation was stable. Six severe dry periods were found in this region
in the past 453-year reconstruction, which were 1592 to 1610, 1649 to 1665, 1687 to 1697, 1740 to 1750, 1818 to 1829 and 1918
to 1933. Five severe wetting periods were 1669 to 1682, 1700 to 1709, 1800 to 1814, 1898 to 1909 and 1935 to 1950. Spectrum
analysis indicated that there existed long-term cycles of 60.4 and 53.4 a, solar cycle of 11 a and short-term cycles of 8,
6 and 4 a in the reconstructed series. 相似文献
17.
LIU Junbo 《武汉大学学报:自然科学英文版》2007,12(6):1109-1112
A new type in situ Cr7C3/γ-Fe ceramal composite coating was fabricated on substrate of hardened and tempered grade C steel by plasma cladding with Fe-Cr-C alloy powders. The ceramal composite coating has a rapidly solidified microstructure consisting of primary Cr7C3/γ- and the Cr7C3/γ-Fe eutectics, and is metallurgically bonded to the degree C steel substrate. The corrosion resistances of the coating in water solutions of 0.5 mol/L H2SO4 and 3.5% NaCl were evaluated utilizing the electrochemical polarization corrosion-test method. Because of the inherent excellent corrosion-resisting properties of the constituting phase and the rapidly solidified homogeneous microstructure, the plasma clad ceramal composite coating exhibits excellent corrosion resistance in the water solutions of 0.5 mol/L H2SO4 and 3.5% NaCl. 相似文献
18.
Shoujia He Chengfei Liao Yanxian Yang Zhixian Pan Yucang Sha Zhonghua Ji 《武汉大学学报:自然科学英文版》2008,13(3):285-290
Based on the theory of ecology, this article conducted a landscape ecological evaluation on Leucaena leucocephala artificial forest in the add-hot valley, Yuanmou Xiaokua hill, using a combination method of qualitative analysis and landscape comprehensive evaluation. The comprehensive evaluation indexes of landscape include forest coverage, biodiversity, stability, soil erosion, environmental quality, availability, scientific research characteristic, economic benefits. Using AHP (analytical hierarchy process), determine the grade of ecological evaluation factors and the weight of evaluation index and calculate the CEI (comprehensive evaluation index) on ecological evaluation. Evaluation results showed that the area CEI was 0.714 225, a better quality of the ecological level, but biodiversity indicators was the lowest. To sum up, it was difficult to maintain ecological restoration effectiveness and process but also guarantee a good biodiversity in the add-hot valleys. We must reasonably arrange the alien species and the native species, in order to obtain a stable and sustainable eco-system. 相似文献
19.
The effect of iron deficiency on heterocyst differentiation and some physiological properties of the filamentous cyanobacteriumAnabaena sp. PCC 7120 was investigated. Under moderate iron limitation conditions, achieved by addition of iron chelator 2, 2′-Dipyridyl
(<80 μmol/L) led to delayed heterocyst differentiation, no heterocyst differentiation was observed under severe iron limitation
conditions, when the concentration of 2,2′-Dipyridyl in the medium was more than 100 μmol/L. it seemed that there are certain
iron-regulated genes or operons whose function is to control heterocyst development. In addition, iron deficiency impaired
the growth. Low iron cells had a decrease in the quantities of pigment content (chlorophyll and phycocyanin content), the
whole cellin vivo absorbance spectra confirmed the decrease, the protein electrophoretic profiles revealed that iron-deficient cells had less
protein bands, with the increase of 2,2′-Dipyridyl, the protein bands was more and more less. And differently, iron deficiency
also caused an increase of ROS (Reactive Oxygen Species) and SOD activity, it suggests that iron deficiency led to oxidative
stress, which generally occured under high-iron conditions.
Foundation item: Supported by the National Natural Sciences Foundation of China (30070154), the Frontier Science Projects Programme of the
Institute of Hydrobiology, the Chinese Academy of Sciences (220316), State Key Project on Cyanobacterial Bloom Control in
Lake Danchi (K9905-35-01)
Biography: Xu Wenllang (1974-), male, Ph. D. research direction: molecular genetics of eyanobacteria. 相似文献
20.
A novel method to synthesize 2,6-bis(p-aminophenyl)benzo[1,2-d;5,4-d′]bisoxazole using 1,2,3-trichlorobenzene as the starting
material through nitration, substitution, hydrogenation, and condensation was reported. During the condensation, the influence
of the amount of SnCl2 on the yield of the product was studied. The electron spectra of the compound were discussed, the results showed that it
is a fluorescence material with large Stokes shift.
Foundation item: Supported by the High Technology Research and Development Program of China (2002AA305109)
Biography: Chen Xiang qun (1969), female, Ph. D candidate, research direction: organic and polymer materials. 相似文献