Systematic authentication codes using additive polynomials

Using additive polynomials related to some curves over finite fields, we construct two families of systematic authentication codes. We use tight bounds for the number of rational points of these curves in estimating the probabilities of the systematic authentication codes. We compare their parameters with some existing codes in the literature. We observe that the parameters are better than the existing ones in some cases.     

Some constructions of systematic authentication codes using galois rings

For q = p ^m and m ≥ 1, we construct systematic authentication codes over finite field using Galois rings. We give corrections of the construction of [2]. We generalize corresponding systematic authentication codes of [6] in various ways.     

Palladium‐catalyzed regioselective C2‐arylation of 5‐aminoindole

Pd(II)‐catalyzed C‐H arylations of 5‐aminoindole using iodobenzenes as aryl source was studied. Despite pivalamide directing group at 5‐position of the indole, the direct C2‐arylation of the indole observed in high yields and with high regioselectivity.     

Classification of permutation polynomials of the form $$x^3g(x^{q-1})$$ x 3 g ( x q - 1 ) of $${\mathbb F}_{q^2}$$ F q 2 where $$g(x)=x^3+bx+c$$ g ( x ) = x 3 + b x + c and $$b,c \in {\mathbb F}_q^*$$ b,c ∈ F q ∗

Designs, Codes and Cryptography - We classify all permutation polynomials of the form $$x^3g(x^{q-1})$$ of $${\mathbb F}_{q^2}$$ where $$g(x)=x^3+bx+c$$ and $$b,c \in {\mathbb F}_q^*$$ . Moreover...     

Catalytic wet air oxidation of 2-nitrotoluidine and 2,4-dinitrotoluene

The rates of wet air oxidation of 2-nitrotoluidine and 2,4-dinitrotoluene in the presence of excess oxygen and at different temperatures and oxygen pressures was investigated. Oxidation experiments were carried out at temperatures between 180 and 225^oC and oxygen partial pressures of 1,0-3,0 MPa, in a 280 mL glass vessel-inserted stainless steel reactor. Copper sulfate (CuSO₄ .5H₂O) was used as a catalyst, and the effect of catalyst loading was studied by varying the concentration: 0.75, 2.5 and 25 mg/L as Cu²⁺. Addition of Cu²⁺ ions in the reaction media accelerated 2-nitrotoluidine oxidation nearly ten times even if it exists in trace amount in the reaction medium (0.75 ppm Cu²⁺). Unfortunately copper did not show catalytic effect for the oxidation of 2,4-dinitrotoluene. This revised version was published online in August 2006 with corrections to the Cover Date.     

Some Artin-Schreier type function fields over finite fields with prescribed genus and number of rational places

We give existence and characterization results for some Artin-Schreier type function fields over finite fields with prescribed genus and number of rational places simultaneously.