Dolomite is a common type of natural soluble rock. The strength rock decreases under the action corrosion, which has significant impact on self-stability and long-term safety tunnel surrounding To reveal microscopic structure evolution strength-damage law carbonate caused by chemical series tests such as corrosion test, uniaxial compression test electron microscope scanning are conducted at dif...

Karst topography covers more than 1/3 of the People's Republic of China in area. The porous, fissured, and soluble nature of the underlying karst bedrock (primarily dolomite and limestone) leads to the formation of underground drainage systems. Karst conduit networks dominate this system, and rainfall takes a crucial role on water cycle at China karst area. Nitrogen loss from the karst system i...

The influence of sodium chloride on dissolution of chalcopyrite and surface sulfur speciation during bioleaching of chalcopyrite with the extreme thermophile Acidianus manzaensis YN-25 was studied. The addition of sodium chloride accelerated the dissolution of chalcopyrite by reducing the accumulation of elemental sulfur layers on the mineral surface, resulting in an increase in the concentrati...

Abstract Significant iron (Fe) loss can occur during continental weathering and efflux to the ocean via runoff, historically affecting global Fe cycling marine ecosystems. Here, we report extremely low content in early Carboniferous (ca. 340 Ma) bauxites southwestern China. These were formed by redeposition of terrestrial soils along paleo‐continental margin western South China Plate warm clima...

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...

Biorelevant in vitro dissolution is a useful technique for qualitative forecasting of the in vivo behavior of a formulation. A biorelevant dissolution medium for simvastatin was developed with a lower concentration of surfactant (0.1% sodium lauryl sulfate, SLS) in the medium as compared with the 0.5% SLS concentration stated in the USP monograph. The slower dissolution rate of simvastatin tabl...

Aceclofenac is an analgesic and anti-inflammatory agent used in the management of osteoarthritis, rheumatoid arthritis and ankylosing spondylitis. The objective of the present work was to investigate the effect of different types of carriers such as polyvinyl pyrrolidone (PVP), polyethylene glycol (PEG) 6000 and sodium lauryl sulphate (SLS) as solubilizer on in vitro dissolution of aceclofenac....

With growing populations and ever increasing pressure on resources, the need to live sustainably with our environment has increased in significance. When considering such anthropogenic pressures, karst landscapes are as vulnerable, if not more so, than any other environment. Such vulnerability arises from the rapid transit times of percolating water, the poor filtering ability of carbonate bedr...

The aims of this study are to increase and explain the mechanism of dissolution enhancement of isradipine using the sonoprecipitation method for stable nanosuspensions. There have been still few of published researches on formulation of isradipine using nanoparticle engineering. Nanosuspension systems were prepared upon various factors including amplitude and the time length of ultrasonication....