The purpose of the present study was to investigate the effect of polyethylene glycol (PEG) molecular weights (6000, 12000 and 20000) as solid dispersion (SD) carriers on the dissolution behavior of simvastatin. SDs with various drug : carrier ratios were prepared by solvent method and evaluated for dissolution rate. Differential scanning calorimetry (DSC), X-ray diffraction (XRD), infrared spe...

Karst rocky desertification is a special kind of land desertification developed under violent human impacts on the vulnerable ecogeo-environment in karst ecosystem. The process of karst rocky desertification results in simultaneous and complex variations of many interrelated soil, rock and vegetation biophysical parameters, rendering it difficult to develop simple and robust remote sensing mapp...

As the major field in petroleum reserve growth, fractured-vuggy reservoir is the key research in the future. However, in the development of fracture-cavity reservoir, collapse may occur in karst cave which greatly affects the oil well output. In order to forecast the cave collapse before drilling, this work adopts the method of span dichotomy reduction to determine the critical karst collapse o...

   The aim of the present study was to develop a single unit, site-specific matrix tablets of aceclofenac allowing targeted drug release in the colon with a microbially degradable polymeric carrier, chondroitin suphate (CS) and to coat the optimized batches with a pH dependent polymeric. The tablets were prepared by wet granulation method using starch mucilage as a binding agent and HPMC K-100 ...

springs are the important water resources, which thier study is necessary in terms of their management and exploitation. in northern iran, the karst springs locate in the central alborz highlands and alluvial springs on the caspian southern coasts.the karst and alluvial springs discharge is variable because of different conditions in terms of aquifer, topography and precipitation .this study ha...

Deep karst depressions with a large volume of water due to a poor water drainage system (caused by a clay layer, etc.) and with steeply sloping sidewalls paludificate in a special way. Peat formation begins with dead vegetative material (leaves, etc.) floating on the water's surface in the center of the karst lake. The peat grows laterally from the center of the depression to its edges and the ...

Slovenian karst areas extend over 43% of the country; limestones and dolomites of the Mesozoic era prevail. In Slovenia karst groundwater contributes up to 50% of the total drinking water supply. The quality of water is very high, despite the fact that it is extremely vulnerable to pollution. The present article is a study and a review of the potential and actual sources of pollution to the gro...

[1] Restricted zones of recent dissolution and secondary aragonite infilling were identified in a coral core collected in 1986 from a living massive Porites colony from the central Great Barrier Reef, Australia. Secondary aragonite needles, 20 mm long, cover skeletal surfaces deposited from 1972 to late 1974 and increase bulk density by 10%. Dissolution is observed above this zone, whereas olde...