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1.
In this paper some new results of strong stability of linear forms in φ-mixing random variables are given. It is mainly proved that for a sequence of φ-mixing random variables {x n , n ⩾ 1} and two sequences of positive numbers {a n , n ⩾ 1} and {b n , n ⩾ 1} there exist d n R, n = 1,2,L, such that a.s. under some suitable conditions. The results extend and improve the corresponding theorems for independent identically distributed random variables. Foundation item: Supported by the National Natural Science Foundation of China(10671149)  相似文献   

2.
Sub 16 is a substitution line with G. hirsutum cv. TM-1 genetic background except that the 16th chromosome (Chr. 16) is replaced by the corresponding homozygous chromosome of G. barbadense cv. 3-79, and T586 is a G. hirsutum multiple gene marker line with 8 dominant mutation genes. The R 1 gene for anthocyanin pigmentation was tagged in Chr. 16 in T586. The objective of this research was to screen SSR markers tightly linked with R 1 by using the F2 segregating population containing 1259 plants derived from the cross of Sub 16 and T586 and the backbone genetic linkage map from G. hirsutum×G. barbadense BC1 newly updated by our laboratory. Genetic analysis suggested that the segregation ratio of red plants in the F2 population fit Mendelian 1:2:1 inheritance, confirming that the red plant trait was controlled by an incomplete dominance gene. Preliminary mapping of R 1 was conducted using 237 randomLy selected F2 individuals and JoinMap v3.0 software. Then, a fine map of R1 was constructed using the F2 segregating population containing 1259 plants, and R 1 was located between NAU4956 and NAU6752, with only 0.49 cM to the nearest maker loci (NAU6752). These results provided a foundation for map-based cloning of R 1 and further development of cotton cultivars with red fibers by transgenic technology. Supported by National Natural Science Foundation of China (Grant No. 30730067) and Programme of Introducing Talents of Discipline to Universities (Grant No. B08025)  相似文献   

3.
The photoluminescence quenching behaviors of ^5D3-^7Fj and ^5D4-^7Fj (J = 0—6) transitions of Tb^3+ in YBO3:Tb under 130—290 nm excitation were systematically investigated. The results revealed that the quenching concentrations of both ^5D3-^7Fj and ^5D4-^7Fj transitions of Tb^3+ in YBO3:Tb were mainly dependent on excitation wavelength. Particularly, the quenching concentrations of ^5D4-^7Fj transitions of Tb^3+ under 130—290 nm excitation were correlated with excitation bands of YBO3:Tb. The quenching concentrations of ^5D3-^7Fj transitions remained at low concentration (2%) under 186—290 nm excitation and then increased gradually with energy of incoming excitation photon when excited at 130—186 nm. This dependence should be involved in their excitation mechanisms and quenching pathway in particular excitation region.[第一段]  相似文献   

4.
Measured results of magnetoelectric (ME) and converse magnetoelectric (CME) effects of TbxDy1-xFe2-y/ Pb(Mg1/3Nb2/3)(1-x)TixO3/TbxDy1-xFe2-y (TD/PMNT/TD) and PMNT/TD/PMNT laminated composites are presented. ME effect was determined by measuring laminate voltage output under a Helmholtz-generated AC field biased by a DC field (0-1 kOe) (1Oe = 79.58 A/m). The CME effect was measured by recording the voltage induced in a solenoid encompassing the ME sample while exposed to a DC bias field and PMNT layer driven by a 10 V AC source. The ME and CME responses in the two laminated structure are linear. The highest values of ME coefficients in TD/PMNT/TD and PMNT/TD/PMNT composites are 384 mV/Oe and 158 mV/Oe, respectively, while the highest values of CME coefficients in the two composites are 118 mG/V and 162 mG/V (1 G=10^-4 T), respectively.  相似文献   

5.
Surface soil samples collected over a high spatial resolution in eastern China were analyzed for carbon isotope composition (δ^13C) of total organic carbon (TOC) and higher plant-derived long-chain n-alkanes, with the latter reported as weighted mean values. The two sets of δ^13C values are significantly correlated and show similar trends in spatial variation. The spatial distribution of δ^13C shows less negative values in the mid-latitudes between 31°N and 40°N and more negative ones at higher and lower latitudes. This is consistent with previously reported carbon isotope data from surface soil phytoliths in the same region and suggests that the mid-latitude area provides relatively favorable growing condi- tions for C4 plants. Furthermore, δ^13C values of both TOC and long-chain n-alkanes from 12 surface soil samples collected from a small grassland in north China displayed similar carbon isotope values and the difference between paired δ^13C of a soil samples remains relatively constant. Our data demonstrate that in eastern China, soil δ^13C composition of both TOC and long-chain n-alkanes is effective indicators of C3/C4 ratios of the prevailing vegetation. This work suggests that -22‰ and -32‰ are good es- timated end members for the weighted mean δ^13C values of long-chain n-alkanes (C27, C29 and C31 n-alkanes) from soils under dominant C4 or C3 vegetation, allowing us to reconstruct paleovegetation trends.  相似文献   

6.
On the basis of our previous work, a configuration of H 5 + has been presented that is a square center structure, and the energy for the structure of H 5 + has been obtained by IACQM. The result showed that there is an extreme energy Ee: −2.45981 [2 Ry] atR = 2.50a 0. It indicates that the square center structure of H 5 + system has the certain stability, which is a possible configuration of H 5 + .  相似文献   

7.
与产品相关的谣言影响个体对于产品的判断及购买欲望,进而波及整个供应链中产品的市场需求.考虑个体的情绪和个体对谣言的判断,将经典谣言传播模型中的免疫者R细分成为蒙蔽者R_a和清醒者R_d,两种状态的个体都知道但不传播谣言,不同的是R_a受谣言蒙蔽相信谣言不购买产品,R_d作为清醒者不相信谣言,且继续购买产品.基于系统动力学构建CISR_aR_d谣言传播模型,对模型进行稳定性证明,探讨谣言攻击对产品需求的遏制情况,并在此基础上进行了数值模拟.研究表明,与产品相关的谣言严重制约产品的市场需求,商家在应对谣言攻击时所作出的正面宣传对于产品需求的恢复有其积极意义.  相似文献   

8.
The interactions between NO, O2 and their mixture on BaAl2O4, as well as the reaction of NOx with soot in the presence of O2, have been investigated using Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS). NO adsorption produces only nitrites species in the absence of O2. NO2 adsorption produces nitrates species besides nitrites species. The produced nitrites will further react with O2, Osurf^-. and Olattice^2- to form nitrates. The reaction of NOx with soot begins with the reaction of nitrates with soot oxygenated complex (C(O)), which is regarded as the key and rate determining step. A reaction pathway is proposed for the catalyzed reaction of NOx with soot in the presence of O2.  相似文献   

9.
0IntroductionThere are luxuriant biotic resources in PanxiArea,where mineral resources,hydraulic re-source and biotic resources are preponderant.Thedevelopment of Panxi Area began withthe exploita-tion of mineral resources,which has established asolidfoundationfor the development of Panxi Area.Withthe consumption of the mineral resources,be-ing a kind of nonrenewable resource,the mineral in-dustry contributes less and less to the developmentof Panxi Area and does more and more harmto en-vir…  相似文献   

10.
图分解问题已在很多邻域中得到了广泛的应用。用P5表示5个顶点的路,C5表示5个顶点的圈,本研究讨论了完全图Kn分解成5个顶点的路P5和圈C5的存在性,给出完全图Kn存在{P5,C5}-强制分解的充分必要条件是n≥7(n≠8),以及完全图Kn存在{P5,C5}-分解的充分必要条件是n≥5(n≠6)。  相似文献   

11.
The theoretical spatial power spectrum of a dipole located at ( r0, θ60, φ0) can be fitted by a straight line in logarithmic scale when n is larger than 2. Based on the spherical harmonic coefficients of geomagnetic field during 1900-1995, the depth( r0) of source-layer of every 5a is calculated. The results show that r0 decreased from 1900 to 1960; abruptly changed from 1945 to 1950 related to some kind of disturbance; decreased again from 1960 to 1975; increased from 1975 to 1985; and kept stable after 1985. Then the mean energy density (MED) of each year is induced to its corresponding r0. We find that MED of dipole field kept nearly unchanged from 1900 to 1960. While, MED of non-dipole field increased. The change of r0 coinciding with the geomagnetic secular variation, impulse and length-of-day happened around 1970, suggesting that the change of r0 may be related to the impulse. The variation in the fluid flow in the outer-core caused by the core-mantle coupling is a plausible candidate in explaining the changes in geomagnetic Jerk, length-of-day, and r0.  相似文献   

12.
For weighted sums of the form where {a nj , 1 ⩽jk n ↑∞,n⩾1} is a real constant array and {X aj , 1≤jk 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.
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   

14.
A general framework of stochastic model for a Markov chain in a space-time random environment is introduced, here the environment ξ^*:={ξ1,x∈N,x∈ X}is a random field. We study the dependence relations between the environment and the original chain, especially the "feedback". Some equivalence theorems and law of large numbers are obtained.  相似文献   

15.
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   

16.
【目的】研究斑点鳟Oncorhynchus mykiss外部形态特征与内部消化系统结构。【方法】观察并描述斑点鳟外部形态特征,测量30尾斑点鳟的外部形态参数,对其进行相关性分析;解剖观察斑点鳟的消化系统结构特征。【结果】斑点鳟外部形态参数全长(LT)与体长(LB)的相关关系为LT=1.21 LB-3.25(R2=0.948),体质量(W)与全长(LT)的关系为W=0.001 LT3.562(R2=0.754),其余几项形态参数之间相关性较低;可数性状背鳍、臀鳍、腹鳍、胸鳍、尾鳍的鳍条数分别为6~12、9~15、10~24、20~28、23~33;具有1条侧线;第1鳃弓鳃耙数为15~18。斑点鳟为典型的肉食性鱼类,其消化系统结构特征为口咽腔较小,颌齿发达;食道短粗;胃发达,呈V形,分化明显;肠在腹腔内呈两个盘曲,肠长/体长为0.503±0.09;幽门盲囊数为48~72个。【结论】该实验结果可为斑点鳟的消化生理研究以及养殖管理提供科学的理论依据。  相似文献   

17.
【目的】获得耐受高铵浓度的优良养殖小球藻(Chlorella vulgaris)品系,可以有效防止其在养殖过程中被轮虫,纤毛虫等污染生物吞食。【方法】首先对小球藻进行紫外线诱变,然后用高浓度NH_4HCO_3作为筛选压力对其进行筛选。【结果】筛选到具有生长优势的小球藻突变株B4和C6,培养12d,在NH_4HCO_3浓度为800mg/L、1 000mg/L、1 200mg/L条件下,B4和C6的生物量比出发藻株分别提高41.18%和9.54%,32.64%和29.41%,37.74%和22.85%;对比出发藻株,B4和C6的最大光能转化效率有显著提高。【结论】突变株B4和C6在高铵培养条件下更能显示生长优势,且它们的生长优势可能来自光合效率的提高。  相似文献   

18.
In this context, we mainly study the behavior in the neighborhood of finite singular points for k-regular functions in 1 R 1 n with values in R 0,n . We get a Laurent expansion of them in an open set, prove its uniqueness, give the definitions of k-poles, isolated and essential singular points and removable singularity, discuss some properties, and further obtain the residue theorems.   相似文献   

19.
This paper reported about a polymer of acyl imine synthesized by 3-morpholinone(M) and ε-caprolactone(CL) with zinc powder as catalyst. The influence of reaction temperature, reaction time and monomer ratio on the copolymerization reaction was studied. Investigation of monomer reaction ratio and differential scanning calorimeter (DSC) indicated that the copolymer poly(3-morpholinone-ε-caprolactone) was a block copolymer, solubility in water, degradation characteristics in vitro and controlled release of 5-FU was also studied. The results showed the hydrophilicity of the copolymer increased with the increasing of M content in the copolymer. With the enhancement of hydrophilicity its degradation rate and drug releasing rate increased as well. Biography: ZHONG Min(1963–), female, Visiting researcher, Associate professor at College of Xinyang Profession Technology, research direction: organic synthesis.  相似文献   

20.
Let F(S) be the free algebra of type (,∨,→) generated by the non_empty set S, it is proved that the logical equivalent relation defined by means of R 0_semantics is a congruence relation on F(S) and the corresponding quotient algebra is said to be the R 0_semantic Lindenbaum algebra. Taking R 0_semantic Lindenbaum algebra as a prototype, the concepts of implicational lattices and regular implicational lattices which are generalizations of the concept of Boolean algebras are introduced. Besides, the concept of fuzzy implicational spaces is introduced and the representation theorem of regular implicational lattices is obtained by means of fuzzy implicational spaces. In case of Boolean algebras, the corresponding fuzzy implicational spaces are zero_dimensional compact Hausdorff spaces and herefrom it is proved that the famous Stone's representation theorem of Boolean algebras is a corollary of the representation theorem of regular implicational lattices.  相似文献   

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