نتایج جستجو برای: dolomite
تعداد نتایج: 1838 فیلتر نتایج به سال:
The progressive crystallization of dolomite has been investigated in the temperature range of 90 to 41o ~ by means of X-ray powder diffraction, electron microscopy, and infra-red spectroscopy. Short-time, low-temperature experiments ( ~ 145 ~ yielded dolomites with a high defect density. In detail, lattice faults can be described as: Random succession of more or less ordered cation domains, pro...
Soil on the dolomites of Samobor and Zumberak hills developed as a consequence of interaction of specific pedogenetic factors. The zone of saccharoidal Triassic dolomites is characterized by heavily dissected relief with tent-like crests with steep sloping sides and cut in "V"-shaped valleys, displaying a great density of valley network. Dolomite parent rock is poorly permeable with a shallow, ...
Based on an integrated geochemical characterized by extremely high Sr and petrographic investigation of dolomites concentrations, which reflect high from two cores drilled on Great Bahama concentrations of Sr in the pore fluids. Bank, we have determined three different The high concentrations of Sr in the pore mechanisms of formation for the dolomites fluids arise through the continued which ar...
One of the major drawbacks that hinder the industrial competitiveness of the calcium looping (CaL) process for CO2 capture is the high temperature (∼930-950 °C) needed in practice to attain full calcination of limestone in a high CO2 partial pressure environment for short residence times as required. In this work, the multicycle CO2 capture performance of dolomite and limestone is analysed unde...
There are concerns that Mg-calcite crustose coralline algae (CCA), which are key reef builders on coral reefs, will be most susceptible to increased rates of dissolution under higher pCO2 and ocean acidification. Due to the higher solubility of Mg-calcite, it has been hypothesised that magnesium concentrations in CCA Mg-calcite will decrease as the ocean acidifies, and that this decrease will m...
Examination of piston cores and, particularly, sediments collected by the Deep Sea Drilling Project has shown that authigenic dolomite occurs in a wide range of sedimentary associations. While the trace to a small percentage of dolomite often encountered in pelagic carbonate sequences may be a result of authigenesis under "normal" deep-sea conditions, the few studies to date seem to indicate th...
The aim of the present study was to evaluate histologically and radiographically the tissue response to dolomite [CaMg(CO3)2] and its osteogenic potential in the repair of bone cavities in the calvaria of rats. A bone defect 10 mm in diameter and 1 mm deep was made in the calvaria of male Wistar rats. The defects were filled with dolomite, inorganic bovine bone (positive control), or coagulum (...
Bulk X-ray mineralogy of 47 hemipelagic mud and clay samples from the Blake Outer Ridge has revealed that the sediments contain low magnesian calcite, calcian dolomite, ferroan dolomite, and magnesian siderite. Dolomite and siderite are authigenic and occur as rhombohedrons scattered through the sediments, whereas calcite is mostly biogenic. Pliocene dolomitic lenses are made up of interlocking...
Analysis of samples of the 0 to 10-cm soil depth collected at 65 locations under six vegetation communities snowed that prairie and cedar-hardwood communities occurred on calcareous (range, pH 6.97.9) soils with low silt concentrations (20-54%), and that pine and oak communities occurred on acid (pH 4.36.3) soils with high silt (54-80%); this represented a distinction between communities on soi...
A structural study has been undertaken on a cobaltoan dolomite, with chemical formula CaMg0.83Co0.17(CO3)2 (cal-cium magnesium cobalt dicarbonate), from Kolwezi, Democratic Republic of Congo. Pale-pink euhedral cobaltoan dolomite was associated with kolwezite [(Cu1.33Co0.67)(CO3)(OH)2] and cobaltoan malachite [(Cu,Co)2(CO3)(OH)2]. A crystal with a Co:Mg ratio of 1:5.6 (SEM/EDAX measurement), tw...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید