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1.
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
2.
The principles of the new maximal operator H* we defined are discussed. We prove that it is bounded from martingale Hardy-Lorentz L^Xp.q[0,1) to the Lorentz L^Xp.q[0,1) for 1/2〈 p〈∞, 0〈~ q ≤ ∞, where X is any Banach space. When the Banach space X has the RN property, the sequence dnHnf converges to f a.e. Meanwhile the convergence in L^Xp norm for 1≤p〈∞ is a consequence of that the family functions K (n∈N) is an approximate identity. 相似文献
3.
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
4.
By using an LKB-2277 bioactivity monitor and ampoule method, the fundamental thermogenesis curves of the metabolic process
of liver mitochondria fromCarassius auratus hybrid carps and the toxic effect of Na2SeO3 on it were studied at 28°C. From the thermogenesis curves, the thermokinetic equations were established under different condition.
The kinetics show that Na2SeO3 has toxic action on the metabolism process ofCarassius auratus hybrid carps liver mitochondria.
Foundation item: Supported by the National Science Foundation of China (29973030, 30170010 and 5020310), Chenguang Project of Wuhan and National
Postdoctor Foundation of China
Biography: Li Xi (1968-), female, Associate pofessor, research direction: biothermochemistry and biomaterials. 相似文献
5.
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
6.
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
7.
Tao Feng HongMei Peng YingMing Yao Yong Zhang Qi Shen YanXiang Cheng 《科学通报(英文版)》2011,56(14):1471-1475
The synthesis, characterization and luminescent properties of aluminum complexes containing a dianionic N-aryloxo functionalized β-ketoiminate ligand are presented. 4-(2-Hydroxy-5-R-phenyl)imino-2-pentanone (R = Me, L1H2; R = tert-butyl, L2H2) ligands reacted with AlEt3 in tetrahydrofuran to give the aluminum complexes (L1AlEt)2 (1) and (L2AlEt)2 (2) in reasonable isolated yields. X-ray diffraction revealed that complexes 1 and 2 have solvent-free centrosymmetric dimeric structures, and each aluminum center has distorted trigonal bipyramidal geometry.
At room temperature, complexes 1 and 2 exhibit blue photoluminescence in acetonitrile with maximum emission wavelengths of 419 and 413 nm, respectively. 相似文献
8.
SHI GuoSheng DING YiHong 《科学通报(英文版)》2008,53(21):3277-3280
The reaction mechanism between (Me)3CO· radical and trans-3-hexene in benzene was studied for the first time at the B3LYP/6-311++G(d,p)//B3LYP/6-31G(d)+ZPVE level. Two distinct elementary channels were identified as: (1) abstraction-addition; (2) addition-addition-elimination. Analysis of the potential energy surface demonstrates that for the title reaction, channels (1) and (2) have the major and minor contribution, respectively. Our calculated results can well explain the recently observed product distribution by Coseri et al. (J. Org. Chem. 2005, 70, 4629). However, we found that the addition-abstraction channel proposed by Coseri et al. is kinetically infeasible. 相似文献
9.
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
10.
WANG YuQing WU YuQin BIAN XiuFang 《科学通报(英文版)》2007,52(11):1441-1445
Viscosities of molten Al(1-x)Mgx(0≤x≤0. 10 alloys have been measured in the temperature range of 973 K--1173 K by a torsional oscillation cup method. The viscosity dependence on temperature for Al(1-x)Mgx(0≤x≤0. 10 melts obeys Arrhenius equation. The viscosity increases with increasing magnesium concentration in the investigated system. There is an important relationship between viscosity and its glass-forming ability for metallic melt. 相似文献
11.
xuwen-liang LIUYong-ding ZHANGCheng-cai LIJuan 《武汉大学学报:自然科学英文版》2004,9(4):498-502
The fecC gene encoding a putative iron (Ⅲ) dicitrate transporte rwas cloned from nitrogen-fixing cyanobacterium Anabaena sp. PCC 7120, and inactivated. The mutant grows normally in medium with NO3^- , NH1^- or without combined nitrogen. But in iron-deficient medium, the mutant grows slowly. Photosynthetic properties were compared between the mutant and the wildtype strain, the content of photosynthetic pigments in the mutant is lower than that of the wild-type. The results of RT-PCR experiments show that the fecC gene is expressed under iron-deficient conditions, but is not expressed under iron-replete conditions. These results revealed that fecC gene product is required for optimal growth under iron-deficient conditions in Anabaena sp. PCC 7120. 相似文献
12.
RUAN Ying DAI FuPing WEI BingBo 《科学通报(英文版)》2007,52(19):2630-2635
Rapid growth behavior of ζ phase has been investigated in the undercooling experiments of Cu-14%Ge, Cu-15%Ge, Cu-18.5%Ge and Cu-22%Ge alloys. Alloys of the four compositions obtain the maximum undercoolings of 202 K(0.17TL), 245 K(0.20TL), 223 K(0.20TL) and 176 K(0.17TL), respectively. As the content of Ge increases, the microstructural transition of "a(Cu) dendrite + ζ" peritectic phase → ζ" peritectic phase →, ζ dendrite + (ε+ζ) eutectic" takes place in the alloy at small undercooling, while the microstructural transition of "fragmented α (Cu)dendrite + ζ peritectic phase →, ζ peritectic phase →ζ dendrite + ε phase" happens in the alloy at large undercooling. EDS analysis of the Ge content in peritectic phase indicates that undercooling enlarges the solid solubility of ζ rdendrite, which leads to a decrease in the Ge content in ζ phase as undercooling increases. In the Cu-18.5%Ge alloy composed of ζ peritectic phase, the Ge content in ζ phase increases when undercooling increases, which is due to the restraint of the Ge enrichment on the grain boundaries by high undercooling effect. 相似文献
13.
In this paper,a Littlewood-Paley function characterization of the spaces L p(R),1
相似文献
14.
YIN Xinchun YANG Jie XIE Li . Department of Computer Science Engineering Yangzhou University Yangzhou Jiangsu China . State Key Laboratory for Novel Software Technology Nanjing University Nanjing Jiangsu China 《武汉大学学报:自然科学英文版》2007,12(1):131-134
0 Introduction Being as unique nonlinear components of block ci- pher algorithms, S-boxes provide the most important confusion effect, and directly influence the security of the algorithms. There are many ways to construct S-boxes[1-5]. On one hand, diffe… 相似文献
15.
Ubi1 intron-mediated enhancement of the expression of Bt cry1Ah gene in transgenic maize (Zea mays L.) 总被引:3,自引:0,他引:3
WANG YueBing ;LANG Zhihong ;ZHANG Jie ;HE KangLai ;SONG FuPing ;HUANG DaFang 《科学通报(英文版)》2008,53(20):3185-3190
The cry1Ah gene was one of novel insecticidal genes cloned from Bacillus thuringiensis isolate BT8. Two plant expression vectors containing cry1Ah gene were constructed. The first intron of maize ubiqutinl gene was inserted between the maize Ubiquitin promoter and cry1Ah gene in one of the plant expressing vectors (pUUOAH). The two vectors were introduced into maize immature embryonic calli by microprojectile bombardment, and the reproductively plants were acquired. PCR and Southern blot analysis showed that foreign genes had been integrated into maize genome and inherited to the next generation stably. The ELISA assay to T1 and T2 generation plants showed that the expression of CrylAh protein in the construct containing the ubil intron (pUUOAH) was 20% higher than that of the intronless construct (pUOAH). Bioassay results showed that the transgenic maize harboring cry1Ah gene had high resistance to the Asian corn borers and the insecticidal activity of the transgenic maize containing the ubil intron was higher than that of the intronless construct. These results indicated that the maize ubil intron can enhance the expression of the Bt cry1Ah gene in transgenic maize efficiently 相似文献
16.
A stereotaxic method and apparatus for the <Emphasis Type="Italic">Gekko gecko</Emphasis> 总被引:1,自引:0,他引:1
To study the modulation mechanism of the middle brain of the Gekko to the locomotion, we introduced a stereotaxic method first in literature and developed an apparatus suitable for Gekko gecko, the biggest wall and ceiling climber in nature. We defined the bregma and nasal points as reference points, selected the bilateral infraorbital margin and top point of the maxillary tooth for locating and fixing, and set up the line passing through the bregma and paralleling to a line connecting the bilateral infraorbital margin as x axis. Then, we defined a horizontal plane in the stereotaxic instrument, passing through x axis and the certain point which is 4.8 mm exactly above the nasal point, as the XOY plane; the sagittal plane, i.e. the YOZplane, is the plane which is perpendicular to x axis and passes through the bregma; the plane, i.e. the XOZ plane, which passes through x axis and is perpendicular to the horizontal plane is the coronal plane. We designed a set of head holder which includes three parts: bilateral infraorbital margin clamps, a gecko adaptor holding the rostral side of the upper jaw. The allocation and operation of the head holder is accurate and simple, and the device is low in cost and compatible with standard stereotaxic instrument. 相似文献
17.
ShaoFeng Zhang Dan Yan HuiYing Tang Ming Yang YueSheng Wang XiaoHe Xiao 《科学通报(英文版)》2010,55(18):1870-1876
The toxic effect of different solubilizing excipients on the growth and metabolism of Tetrahymena thermophila BF5 (T.t.BF5) at various concentrations was investigated by microcalorimetry. The thermogenic curves of T.t.BF5 growth were determined at 28°C, and were evaluated by dynamic parameters. The results indicated that the values of growth rate constant (k), maximum power (P1, P2), peak time (T1, T2) and total quantity of heat (Q) varied for different excipients. There was a good linear relationship between k and concentrations (r>0.95, P<0.01). 5% inhibition concentration (IC5) of poloxamer 188, Tween 80, PEG 600, PEG 400 and Tween 20 was 2.18, 1.07, 1.35, 0.58, and 0.045 mg/mL, respectively. After the principal component analysis (PCA), Q, k and P1 could characterize the effect of these excipients on T.t.BF5 growth. Comprehensive evaluation indicated that compared with the control group, poloxamer 188 had the weakest toxicity and Tween 20 had the strongest toxicity. 相似文献
18.
MA JingJing LI LiangBi JING YuXiang KUANG TingYun 《科学通报(英文版)》2007,52(7):896-902
In order to study the functions of cytochrome b559 (Cyt b559) in photosystem two (PSII) activity, mutant S24F of Chlamydomonas reinhardtii was constructed using site directed mutagenesis, in which Serine24 (Ser24) locating downstream of Histidine23 (His23) in α subunit of Cyt b559 was replaced by Phenylalanine (Phe). Physiological and biochemical analysis showed that mutant S24F could be grown photoautotrophically or photoheterotrophically. However, their growth rate was slower either on HSM or TAP medium than that of the control; Analysis of PSII activity revealed that its oxygen evolution was about 71% of wild type (WT); The Photochemical efficiency of PSII (Fv/Fm) of S24F was reduced 0.23 compared with WT; S24F was more sensitive to strong light irradiance than the wild type; Furthermore, SDS-PAGE and Western-blotting analysis indicated that the expression levels of α subunit of Cyt b559, LHCII and PsbO of S24F were a little less than those of the wild type. Overall, these data suggests that Ser24 plays a significant role in making Cyt b559 structure maintain PSII complex activity of oxygen evolution although it is not directly bound to heme group. 相似文献
19.
The R- and AR-indices: Complementing the h-index 总被引:47,自引:0,他引:47
JIN BiHui LIANG LiMing Ronald ROUSSEAU Leo EGGHE 《科学通报(英文版)》2007,52(6):855-863
Based on the foundation laid by the h-index we introduce and study the R- and AR-indices. These new indices eliminate some of the disadvantages of the h-index, especially when they are used in combina-tion with the h-index. The R-index measures the h-core’s citation intensity, while AR goes one step further and takes the age of publications into account. This allows for an index that can actually in-crease and decrease over time. We propose the pair (h, AR) as a meaningful indicator for research evaluation. We further prove a relation characterizing the h-index in the power law model. 相似文献
20.
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