an oral sustained-release floating tablet formulation of metformin hcl was designed and developed. effervescence and swelling properties were attributed on the developed tablets by sodium bicarbonate and hpmc-peo polymer combination, respectively. tablet composition was optimized by response surface methodology (rsm). seventeen (17) trial formulations were analyzed according to box-behnken desi...

Dendrimers are a new class of polymeric materials. They are highly branched, monodisperse macromolecules. The structure of these materials has a great impact on their physical and chemical properties. As a result of their unique behaviour dendrimers are suitable for a wide range of biomedical and industrial applications. The paper gives a concise review of dendrimers' physico-chemical propertie...

The traditional distinction between primary (observation independent) and secondary (observation dependent) qualities is not based on a difference that can be sustained in the full light of contemporary scientific understanding. An alternative division of physical and chemical properties is proposed. Like the traditional division of qualities, the alternative system has two main categories. Pro...

Edwards’ elliptic curve form is popular in modern cryptographic implementations thanks to their fast, strongly unified addition formulas. Twisted Edwards curves with a = −1 are slightly faster, but their addition formulas are not complete over Fp where p ≡ 3 (mod 4). In this short note, we propose that designers specify Edwards curves, but implement scalar multiplications and the like using an ...

Antiviral interferon activity in any one species can be exhibited by a variety of substances that differ in their physical and chemical properties, but the nature of these differences is not understood. Conditions that can lead to the formation of diverse types of interferons have been outlined. Reasons have been adduced why, for certain purposes, purification of interferons is desirable or eve...

Water is a major component of all living things. It is anomalous in many of its physical and chemical properties. Some are essential for life while others have profound effects on the size and shape of living organisms, how they work, and the constraints within which they must operate. Many of water’s basic physical properties can now be explained, at least semiquantitatively, in molecular and ...

Microbial functional diversity in four soils sampled in the vicinity of Wanda Glacier, Antarctic Peninsula, was determined using Biolog EcoPlates at 5°C and 25°C. Comparisons of the patterns of substrate utilization and the diversity index showed differences in community composition, reflecting the heterogeneous distribution of microorganisms in this environment. Differences in microbial divers...

This study evaluates the spatial heterogeneity of the soil chemical properties of surface soils across a 1 ha old-growth subtropical karst forest in southwest China.

Phosphasilenes, P=Si doubly bonded compounds, have received considerable attention due to their unique physical and chemical properties. We report on the synthesis and structure of a chlorophosphasilene coordinated by an N-heterocyclic carbene (NHC), which has the potential of functionalization at the Si-Cl moiety. Treatment of a silylphosphine, ArPH-SiCl₂RSi (Ar = bulky aryl group, RSi = Si(Si...