The Braided product of Ockham algebras

In this paper we introduce an algebraic concept of the product of Ockham algebras called the Braided product. We show that ifL _i MS(i=1, 2, ,n) then the Braided product ofL _i(i=1, 2, ,n) exists if and only ifL ₁, ,L _n have isomorphic skeletons.     

Linear programming with entropic perturbation

In this paper, we derive an unconstrained convex programming approach to solving standard form linear programs through an entropic perturbation. The whole duality theory is established by using only one simple inequality lnz z –1 forz > 0. A curved search algorithm is also proposed for obtaining a pair of primal and dual-optimal solutions. The proposed algorithm is proven to be globally convergent with a quadratic rate of convergence. Computational results are included in support of theoretic findings.The work is partially supported by the North Carolina Supercomputing Center, the Cray Research Award, and the National Science Council of the Republic of China # NSC 81-0415-E-007-10.     

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.     

银微电极微分电位溶出分析法研究

本文首次报道了银微电极微分电位溶出分析法。用化学刻蚀法方便地制作了银微电极，用于ＤＰＳＡ具有背景值低，分辨率好、精密度及灵敏度高，在不搅拌，仅需一定酸度而酸度而无其它介质的条件下就能测试等优点，对人工试样及自来水样分析，结果令人满意。     

稀土丁-异戊共聚橡胶的硫化特性

稀土丁-异戊共聚橡胶(BIC)的两种结构单元都具有高顺式-1,4的特点,在丁/异戊比合适的情况下,其硫化胶具有优良的耐低温性质。本文通过(CZ-S)和TMTD 两种不同的硫化体系,研究了BIC(锦-20)的混炼胶和硫化胶性质。发现,与同样用稀土催化剂聚合的异戊橡胶和顺丁橡胶相比,锦-20有一些值得注意的特点。     

One-Pot Formation of Carbonates from the Reactions of Carbonyl Compounds with Samarium Diiodide and Methyl Chloroformate

Treatment of carbonyl compounds with SmI₂ and methyl chloroformate in the presence of molecular sieves provides the cyclic carbonates or biscarbonates of pinacols. This one-pot reaction proceeds rapidly even with aliphatic ketones. The stereochemistry obtained by this procedure is different from that of conventional pinacolic couplings.     

Multinuclear NMR study of lanthanide(III) complexes of 1,2-PDTA in aqueous solution

The complexation of lanthanide(III) cations with 1,2-propanediaminetetraacetate (1,2-PDTA) in aqueous solution has been investigated by ¹⁰Na, ³⁵Cl, ²H and ¹¹O NMR shift measurements. It has been shown that the contact shifts are dominant for ¹⁷O, ¹⁶Cl and ²H (only for the heavier lanthanide series) and the pseudocontact shifts are dominant for ²⁵Na. It is suggested that the 1,2-PDTA ligand is bound pentadentately via the two nitrogens and the three carboxylates for the lighter lanthanide complexes, hexdentately via the two nitrogens and the four carboxylates for the heavier ones. The numbers of the water coordinated were determined. The small amount of chloride anion in inner coordination sphere was observed.     

Evaluation of Eigenvalues by Successive Variations

A successive variation method was studied and tested on the hydrogen molecular ion H₂⁺. Results show that it takes less computational time than conventional method. It was also found that ground state wavefunction of H₂⁺ can be well approximated by the linear combination of the simplest Gaussian orbitals e^?I(T-a)3     

Computerized flow constant-current stripping analysis for some electroactive organic compounds: application to the determination of erythromycin in urine

The possibility of determining various electroactive organic compounds, e.g., erythromycin and riboflavin, by adsorptive preconcentration at constant potential on a mercury-coated carbon-fibre electrode in a flow system prior to stripping with a reductive constant current, is demonstrated. The advantages of measuring the electrode potential vs. time instead of current vs. electrode potential during stripping, the possibility of operating with non-deoxygenated solutions, the increased linear calibration range is in the multiple scanning mode, and the possibility of using the technique for detection in liquid chromatography, are discussed. An analytical procedure for the determination of erythromycin at the 10(-6)M level in urine after extraction with diethyl ether is described.