醋酸乙烯酯在硅橡胶上的辐射接枝研究

研究了不同溶剂中的醋酸乙烯酯在硅橡胶上的辐射接技状况及接枝后硅橡胶表面结构情况．结果表明：（１）在硅橡胶－乙酸乙酯－醋酸乙烯酯体系中，接枝有自加速效应；（２）适量加入对苯二酚，接枝诱导期延长，接枝速率下降，凝胶效应消失，辐射接技经验关联式为ＲＰ＝０．２７×［Ｄ］（－０．５６０）×［Ｉ］（０．４９０）×［Ｃ］（０．９２０），接核反应为扩散控制反应；（３）不同的溶剂对硅橡胶接枝有不同的影响，如甲醇发生敏化作用，提高接枝速率，而苯发生惰化作用，降低接枝速率；（４）在合适的甲醇和苯配比时，接枝反应几乎恒速进行，用扫描电镜（ＳＥＭ）观察断面，接枝区比较均一，出现微相分离．     

p-aminophenyl phosphate: an improved substrate for electrochemical enzyme immnoassay

An alternative substrate is described for enzyme immunosaasay with electrochemical detection. Alkaline phosphatase (EC.3.1.3.1) activity is determined by using p-aminophenyl phosphate as the enzyme substrate. Enzyme-generated p-aminophenol is detected amperometrically at a glassy carbon electrody by liquid chromatography with electrochemical detection. The oxidation potential obtained for the detectionof p-aminophenol is lower than that for phenol, the previously used substrate product. The detection limit for p-aminophenol is 0.20pmol. A detection limit of 30 pg ml^-1 for digoxin and a 5-min incubationtime for the enzyme reaction were obtained with the new system.     

Synthesis of New Ligand 1,2-Bis{di[（R,R）-1,3,2-oxzaphosphlidine]phosphino}ethane with C_2-symmetric Axis and Application in Rh-catalyzed Asymmetric Hydrogenation

New ligand 1,2-bis{di[（R,R）-1,3,2-oxzaphosphlidine]phosphino}ethane [（R,R）-BDOPPEs 1,2,3 and 4] with C2-symmetric axis and bearing nitrogen and oxygen were synthesized from readily available optically active amino alcohols.Rh complexes with these ligands were highly enantioselective catalysts for asymmetric hydrogenation of N-benzoyldehydroamino acid derivatives and α-functionalized ketones in 99%e.e.and 98%e.e.,respectively.This new class of（R,R）-BDOPPEs 1,2,3 and 4 gave much more effectivity and enantionselectivity than their corresponding non-C2-asymmetric aminophosphine phosphinite.     

Sums of Fourier coefficients associated with Hecke cusp forms

Lithuanian Mathematical Journal - Let Hk denote the space of holomorphic Hecke cusp forms of even integral weight k for the full modular group Γ = SL(2, ℤ). Let λf (n), λg(n),...     

Multiple attribute decision-making method based on projection model for dual hesitant fuzzy set

Fuzzy Optimization and Decision Making - In the decision-making process, retaining the original data information has become a most crucial step. Dual hesitant fuzzy sets (DHFS), which can reflect...     

Some Estimates for $θ$-Type Calderόn–Zygmund Operators and Linear Commutators on Certain Weighted Amalgam Spaces

In this paper, we first introduce some new kinds of weighted amalgam spaces. Then we discuss the strong type and weak type estimates for a class of Calderόn–Zygmund type operators $T_θ$ in these new weighted spaces. Furthermore, the strong type estimate and endpoint estimate of linear commutators $[b, T_θ]$ formed by $b$ and $T_θ$ are established. Also we study related problems about two-weight, weak type inequalities for $T_θ$ and $[b, T_θ]$ in the weighted amalgam spaces and give some results.     

Fractal drums and then-dimensional modified Weyl-Berry conjecture

In this paper, we study the spectrum of the Dirichlet Laplacian in a bounded (or, more generally, of finite volume) open set R ⁿ (n1) with fractal boundary of interior Minkowski dimension (n–1,n]. By means of the technique of tessellation of domains, we give the exact second term of the asymptotic expansion of the counting functionN() (i.e. the number of positive eigenvalues less than ) as +, which is of the form ^/2 times a negative, bounded and left-continuous function of . This explains the reason why the modified Weyl-Berry conjecture does not hold generally forn2. In addition, we also obtain explicit upper and lower bounds on the second term ofN().     

ULTRASONICALLY DISPERSED POTASSIUM AS DEPROTONATING AND COUPLING AGENT──SYNTHESIS OF 1，6－DINITRILES IN SITU

ＵＬＴＲＡＳＯＮＩＣＡＬＬＹ　ＤＩＳＰＥＲＳＥＤ　ＰＯＴＡＳＳＩＵＭ　ＡＳ　ＤＥＰＲＯＴＯＮＡＴＩＮＧ　ＡＮＤ　ＣＯＵＰＬＩＮＧ　ＡＧＥＮＴ──ＳＹＮＴＨＥＳＩＳ　ＯＦ　１，６－ＤＩＮＩＴＲＩＬＥＳ　ＩＮ　ＳＩＴＵＵＬＴＲＡＳＯＮＩＣＡＬＬＹＤＩＳＰ...     

Re(CO)5Br-catalyzed addition of carboxylic acids to terminal alkynes: a high anti-Markovnikov and recoverable homogeneous catalyst

The addition of carboxylic acids to terminal alkynes is efficiently catalyzed by the early transition-metal complex Re(CO)5Br in toluene or n-heptane at 110 degrees C in an air atmosphere, affording the anti-Markovnikov adducts in good yields with high selectivity. In most cases, the reactions afford unusual Z-adduct predominantly. When n-heptane was used as solvent, Re(CO)5Br can be partly recovered from the reaction mixture.     

Phase Selectively Soluble Dendritic Derivative of 4-(Dimethylamino)- pyridine: An Easily Recyclable Catalyst for Baylis-Hillman Reactions

Among the reactions in which C-C bonds are formed, the Baylis-Hillman coupling of aldehydes with α, β-unsaturated carbonylic compounds is currently attracting much interest due to the atom economy, the mild conditions and the generation of functional groups1,2. Furthermore, compared to the Heck, Suzuki and other palladium catalyzed C-C bond forming reaction3, the Baylis-Hillman reaction can be promoted by using organic bases in the complete absence of any metal4. However, almost all the …