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1.
This paper discusses the total irredundance relations between the graph G and its clone-contraction graph H, that is, let H be the clone-contraction graph of G and v1,v2,...,vk be all contraction vertices ofH. IfS is a maximal total irredundant set of H such that A = S ∩ {V1,V2,…,Vk} contains as few vertices as possible, then S'= S-A is the maximal total irredundant set of G. Furthermore, we obtain the bound of the total irredundance A(G) number: irt ≤△(G)/2△(G)+1 n, which n is the order of graph G, and △(G) is maximum degree in G.  相似文献   

2.
Flavonols are plant pigments that are ubiquitous in nature. Morin and other related plant flavonols have come into recent prominence because of their usefulness as anticancer, anti-tumor, anti-AIDS, and other important therapeutic activities of significant potency and low systemic toxicity. The heat of combustion of morin (molecular formula, C15H10O7·H2O) in oxygen was measured by a rotating-bomb type combustion calorimeter, the standard molar enthalpy of combustion of morin at T = 298.15 K was determined to be Δc H m (C15H10O7·H2O, s) = −(5 937.99 ± 2.99) kJ · mol−1. The derived standard molar enthalpy of the formation of morin in solid powder state at T = 298.15 K, Δf H m (C15H10O7·H2O, s), was −(1 682.12 ± 3.58) kJ · mol−1, which provide an accurate data of the stability of morin to the pharmacy and pharmacology. Biography: HOU Hanna(1956–), female, Visiting researcher, Associate professor of Hubei University of Education, research direction: thermochemistry.  相似文献   

3.
The reaction between Laccase ando-methoxyphenol have been studied by LKB-2107 batch microcalorimetry system. Thermodynamic parameters Δ r H m , ΔG o , ΔG T and kinetic parameters (K m ,k 2) have been determined. The process of the reaction has been analyzed from changes in energy by using the transition state theory. Two methods for enhancing catalytic power of Laccase are proposed. The results shown that formation of an enzyme-substrate complex is “anticatalytic”. The enter and sole source of catalytic power is the stabilization of transition state; reactant-state interactions are by nature inhibitory and only waste catalytic power. Supported by the National Natural Science Foundation of China Wang Tianzhi: born in 1968. Ph D  相似文献   

4.
The Pólya conjecture and its connection with the weak Weyl-Berry conjecture are studied Specifically let Ω⊆R n (n≥1) be a non-empty bounded open set with boundary ∂Ω. LetN 0(λ, −Δ,Ω) be the Dirichlet counting function and φ(λ) the associated Weyl term. If the interior Minkowski dimension of ∂Ω is δ∈[n−1,n], then under certain realisable conditions we prove that for λ sufficiently large the Pólya conjecture φ(λ) −N 0(λ,−Δ,Ω)≥0 is true. Under related conditions we also prove thatϕ(λ)−N 0(λ,−Δ, Ω)≈λ5/2, as λ→+∞. That is, the Weak Weyl-Berry conjecture is true. Similar results are obtained for the Neumann counting function. Partially supported by the National Natural Science Foundation of China and the Royal Society of London Chen Hua: born in March 8, 1956, Professor  相似文献   

5.
Nanometer ferromagnetic metal-semiconductor matrix Fe−In2O3 granular films are fabricated by the radio frequency sputtering. Magnetic properties and the giant magnetoresistance (GMR) effect of Fex(In2O3)1−x granular film samples are studied. The result shows that the magnetoresistance (MR) ratio Δρ/ρ 0 value of the granular film samples with Fe volume fraction x=35% is 4.5% at room temperature. The temperature dependence (T=1.5–300 K) of the MR ratio Δρ/ρ 0 value of Fe0.35(In2O3)0.65 granular films shows that Δρ/ρ 0 value below 10 K increases rapidly with the decrease of the temperature, and when T=2 K, Δρ/ρ 0 value is 85%. Through the study of the dependence of low field susceptibility on temperature and the hysteresis loops at different temperatures, it has been found that, when the temperature decreases to a critical point T p=10 K, the change of the structure in Fe0.35)In2O3)0.65 granular films results in the transformation of state from ferromagnetic to spin-glass-like. The remarkable increase of the MR ratio Δρ/ρ 0 value of Fe0.35(In2O3)0.65 granular films below 10 K seems to arise from the peculiar conducting mechanism of the granular film samples in the spin-glass-like state.  相似文献   

6.
An upper bound is established on the parameter Γ -(G) for a cubic graph G and two infinite families of 3-connected graphs G k, G * k are constructed to show that the bound is sharp and, moreover, the difference Γ -(G * k)-γ s(G * k) can be arbitrarily large, where Г -(G * k) and γ s(G * k) are the upper minus domination and signed domination numbers of G * k, respectively. Thus two open problems are solved.  相似文献   

7.
Kinetic studies of the decomposition reaction of dinuclear Fe(Ⅱ) adducts [Fe2(N-Et-HPTB){O2P(OPh)2}](Cl- O4)2 (1) and [Fe2(N-Et-HPTB) {O2P(Ph)2}] (ClO4)2 (2) with O2 have been carried out at low temperature using UV-vis spectra. The decomposition reaction of Fe(Ⅱ)/O2 adducts was first-order in the experimental conditions, and the activation parameters were obtained. ?H¹ = 85.62 kJ·mol-1, ?S¹ = 19.43 J·mol-1·K-1 for compound (1) and ?H¹ = 97.97 kJ·mol-1, ?S¹ = 55.68 J·mol-1·K-1 for compound (2). These results are similar to those of dioxygen adducts of other metals complexes and natural enzymes such as methane mono- oxygenase (MMOH).  相似文献   

8.
A series of sandwich-type tungstoarsenates heteropoly compounds with As/W ratio of 4/30, Na16[As4W30M4(H2O)2O112]·XH2O (M = Zn,Cu,Co,Ni,Mn and Cd), have been synthesized for the first time and structurally characterized by elemental analysis, IR and 183W NMR spectra. The crystal structure of Na16[As4W30Cu4(H2O)2O112]·63H2O was determined to be a triclinic system, of P1 symmetry, a = 1.2721(3) nm, b = 2.451 6(5) nm, c = 2.6450(5) nm, α= 89.90(3)°,β= 77.32(3)°, γ= 89.96(3)°, 2=2. Using tetrahepty lammonium bromide as a phase transfer reagent, [As4W30Cu4(H2O)2O112]16- was transferred from aqueous solution to organic phase (benzene), and the heteropolyanion lost the coordination water molecules to form the coordination-unsaturated ion. After lactic acid was added to the benzene solution, the coordination-saturation was recovered. By esterification reaction between lactic acid and cholesterin, the latter was attached to the heteropolyanion indirectly. Therefore, a new type of lyotropic liquid crystal was obtained, which was characterized by a polarimicroscope, DSC and variable temperature wide-angle X-ray diffraction.  相似文献   

9.
The problem of prescribing scalar curvature in S2 is discussed, and the solvability of the e-quation - Δu + 2-Reu = 0 on S2, is given, where R∈C0(S2). It is known that there are some obstructions . Some new results are given by seeking a solution of the minimax type. For example, supposing that R is G symmetric and is constant on the set of fixed points on S2 under G (where G is a subgroup of O(3)), It is proved that the equation is solvable if and only if R is positive somewhere.  相似文献   

10.
An allowable generalized quantum gate (introduced by Long, Liu and Wang) has the form of U = Σ k=0 d−1 c k U k , where U k’s are unitary operators on a Hilbert space H and |Σ k=0 d−1 c k |⩽1 and |c k |⩽1 (0⩽kd−1). In this work we consider a kind of AGQGs, called restricted allowable generalized quantum gates (RAGQGs), satisfying 0 < Σ k=0 d−1|c k |⩽1. Some properties of the set RAGQG(H) of all RAGQGs on H are established. Especially, we prove that the extreme points of RAGQG(H) are exactly unitary operators on H and that B(H)=R + RAGQG(H).  相似文献   

11.
Binuclear manganese complex [(bipy)2Mn2(μ-O)(μ-Ac)2(H2O)2](ClO4)2 was synthesized by the reaction of MnAc3 · 2H2O with 2,2′-bipyridine in the HAc-NaAc buffer (pH = 4.0). X-ray diffraction result for the single crystal shows that the crystal is monoclinic, space group C2/C, with a = 3.408 2(7),b = 0.864 4(2),c = 2.174 9(4) nm, β= 105.2∘, V=6.186(2) nm3, Z= 8. There are two very strong peaks of UV-Vis spectrum in the range of 400–600 nm, which are similar to those of Mn catalase and Mn ribonuleotide reductase extracted from organisms. Cyclic voltammogram shows that the complex in CH3CN undergoes quasi-reversible one-electron reduction and oxidation at E1/2=1.15V.  相似文献   

12.
LetX be a complex quasi-Banach space and Φ:[0,∞)→[0,∞) an increasing convex function with Φ(0)=0, and Φ∈Δ2. ThenL Φ * (X) is a quasi-Banach space with continuous quasi-norm andL Φ * (X) has the ARNP if and only ifX does. Supported by the National Natural Science Foundation of China Liu Peide: born in 1943, Professor  相似文献   

13.
Through the anaerobic chromatography on the columns of DEAE 52, Q-Sepharose and Sephacryl S-200, a nitrogenase MoFe protein (△nifZ Av1) was obtained from a nifZ deleted mutant of Azotobacter vinelandii (stain DJ194).The results of Western blotting after anoxic native electrophoresis and SDS-PAGE showed that △nifZ Av1 was similar to wild type MoFe protein (OP Av1) at the electrophoretic mobility, molecular weight and subunit composition. Furthermore, △nifZ Avl was also similar to OP Av1 at the molybdenum content, EPR signal (g≈4.3, 3.65 and 2.01), and the molar extinction coefficient (△ε) of circular dichroism (CD)at 660 nm region. All of these indicated that, besides having the same α2β2 composition as OP Av1, the △nifZ Av1 also contained equal amount of reductive FeMoco in the spin state of S=3/2 to OP Av1. However, the iron content and substrate (C2H2, H^ and N2)-reduction activity of △nifZ Av1 were 74% and 46%-50% of those of OP Av1, respectively. Furthermore, the △ε at around 450 nm, which reflects P-cluster in Av1, was obviously lower than that of OP Av1. It suggested that the difference between △nifZ Avl and OP Av1 resulted from P-cluster rather than FeMoco, and from the half number of P-cluster in △nifZ Av1, but the composition or redoxstate of P-cluster in △nifZ Av1 were not changed. Thus it could propose that △nifZ Av1 is composed of two different αβsubunit pairs. One is a FeMoco-and P-cluster-containing pair, and the other is a P-cluster-deficient but FeMoco-containing pair. Since the deletion of nifZ gene leads to the deficiency of only one of two P-clusters in a α2β2 tetramer, the assembly of P-cluster may not simply depend on one gene product, and so a possible mechanism of NifZ is supposed here.  相似文献   

14.
The Raman and IR spectra of LnTPPTS·10H2O [Ln=La,Sm, TPPTS=P(m-C6H4SO3) 3 3− ] complexes are reported. Based on the observed Raman and IR characteristic frequencies, a vibrational assignments has been made for these complexes. Coordination induces a lengthening of the S−O bonds and a shortening of the C−S bond. The C−S stretching frequencies should therefore increase while the position of the should move to a lower wavenumber. Vibrational modes of metal-oxygen polyhedron V (La-O) at 146, 168,253 cm−1 are the structural charactrization for coordinate bond of LnTPPTS complexes. Chen Zhenhua: Born in 1938, Professor  相似文献   

15.
利用一组物料、热量守衡式及其他有关约束关系,建立了氢还原竖炉模拟模型,可定量考察消耗量、生成量和氮气、CO兑入成分、DRI金属化率、入炉煤气温度等的关系。模拟结果表明:兑入CO可使入炉煤气量从纯氢还原的1 650N·m3左右下降到1 200N·m3左右;当CO和H2的体积之比V(CO)/V(H2)约为0.6时,氮气兑入量约为0,竖炉能量利用最佳;当V(CO)/V(H2)体积比为0.3时,最佳氮气兑入成分约为11%;纯氢还原最佳氮气兑入成分约为25%;兑入氮气可以减少入炉氢气的量,但不能减少入炉气体的总量。对氢还原竖炉模拟结果可为其工艺设计、操作和节能等提供参考信息。  相似文献   

16.
The solubility parameters of cellulose acrylate substituted degree 2.12(CEA) have been calculated from the measured retention data by inverse gas chromatography at various temperatures. The weight frac-tion activity coefficients of the solvents at infinite dilution(Ω1∞),the Flory-Huggins thermodynamic in-teraction parameters between CEA and solvents(χ 1∞2),the excess molar heats of mixing(△H1s),the par-tial molar heats of mixing at infinite dilution(△H1∞),the solubility parameters of solvent(δ1),and the solubility parameters of CEA(δ2),were calculated at various temperatures. The δ2 of the CEA was 17.32,18.00,18.13,18.54,19.39 at 55,60,65,70 and 75℃,respectively.  相似文献   

17.
HARMFUL ALGAL BLOOM ACTS UPON IMPORTANT ENVIRON-MENTAL PROBLEMS IN COASTAL WATERS.A UNIFIED AND IM-PLEMENTING METHOD FOR SURVEY AND MONITORING ALGALBLOOMS HAS BEEN DEVELOPED SINCE LAST DECADE.HOWEVER THERE IS A DATA GAP OF ABOUT TENS YEARS IN THE PERIOD W…  相似文献   

18.
用摩尔比为2:1的邻香草醛(C_8H_8O_3)与L-胱氨酸(C_6H_(12)N_2O_4S_2)反应,合成了一种新的双Schiff碱化合物--双{2-[(3-巯基丙酸钠)-2-亚胺基-甲基]-6-甲氧基-苯酚}(OVCS)。通过元素分析、红外光谱、核磁共振等手段对其组成和结构进行了表征,确定其化学式为Na_2(C_(22)H_(22)N_2O_8S_2),采用TAM air微量热仪测定了新合成的Schiff碱化合物(OVCS)在305.15 K时对粟酒裂殖酵母细胞作用的产热曲线;根据产热曲线计算了在OVCS作用下,粟酒裂殖酵母细胞生长代谢的最大发热功率p_(max)、速率常数k、传代时间tG、抑制率I和半抑制浓度C_(I,50)等热动力学参数。通过实验可以发现随着OVCS浓度的增加,粟酒裂殖酵母细胞的生长代谢速率常数k、生长代谢的总热效应Q_(total)、最大发热功率p_(max)均减小,抑制率I、达到生长代谢最大功率所需时间t_(max)、传代时间tG均增加等规律,半抑制浓度C_(I,50)为35.99 mg/L(或9.62×10~(-2)mol/L)。实验结果表明,OVCS对粟酒裂殖酵母细胞有抑制作用,且浓度越大,抑制作用越强。  相似文献   

19.
0 IntroductionInrecentyears,studiesonBinghamfluid ,suchasElec trorheologicalfluid ,areactivelypursued[1 6] .Rheologicaltechniqueshavebeenplayinganimportantroleinsyntheticchem istry .Therheologicalphasereactionmethodisthe processofpreparingcompoundsormaterialsfromasolid liquidrheologicalmixture.Thatis,thesolidreactantsarefullymixedinapropermolarratio ,andmadeupbyaproperamountofwaterorothersolventstoaBinghambodyinwhichthesolidparticlesandliquidsubstanceareuniformlydistributed ,sothattheprodu…  相似文献   

20.
The solubility properties of ZnCl\-2/ZnAc\-2/ZnSO\-4_Met_H\-2O systems at 25℃ in the whole cocentration range have been investigated by phase equilibrium method. The results indicate that ZnAc\-2 and ZnSO\-4 systems are both simple systems, which do not exist any compound; there are 2 complexes formed in ZnCl\-2 system: Zn(Met)Cl\-2 and Zn(Met)\-2Cl\-2·2H\-2O. Under the direction of phase equilibrium result, 2 solid complexes have been prepared in water and characterized by chemical analysis, IR, X_ray diffraction. Their combustion energies have also been determined by means of a RBC_type_1 rotating_bomb calorimeter, and their standard enthalpies of formation, Δ f, coor(s)H O-, have been calculated which are (-828.32±3.00) kJ·mol -1 and (-1 117.08±6.15) kJ·mol -1, respectively.  相似文献   

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