OBJECTIVE The optimal threshold of the infusion volume of cement has been a continuous subject in percutaneous vertebroplasty (PVP). This study verifies a causal relationship between the cement volume and the clinical outcome, and suggests the parameters of the appropriate volume of cement in PVP. METHODS This is a retrospective study. One hundred nine patients, who underwent PVP between 2012...

In this study, we evaluated a two-step process for detoxification of waste roofing slate, involving cement hydrate removal and low temperature detoxification using oxalic acid. These treatments were conducted on raw material and intermediate product, respectively. Cement hydrate removal effectively eliminated most Ca-containing cement hydrate components from the raw material under the following...

ABSTRACT: Overall plant growth and microbial biomass can be effected by dust accumulation. The chloroform fumigation-extraction method was used to evaluating the effect of cement dust pollution emitted from Kurdistan cement factory on soil microbial biomass carbon. Chlorophyll content (a, b and total) of plants species was measured in different distance from cement factory. Mic...

this study experimentally investigates the effect of multi-walled carbon nanotubes (mwnt’s), as a reinforcing material, on the physical properties of heavy-weight oil well cements. a candidate well is selected and the properties of the cement slurry used in a problematic section of the well are tested in the laboratory. carbon nanotubes (cnt’s) are added as fibers to the cement slurry and the i...

recent tendencies in concrete technology have been towards to high- performance concrete with a low water-cement ratio. however, high performance concretes have some problems. one of the problems is early-age cracking due to autogenous shrinkage. this study presents the results of an experimental investigation carried out to evaluate the autogenous shrinkage of high-strength concrete. accordin...

in this study, the effect of cement content on concrete performance in corrosive environments is investigated on concrete mixtures having the same water/cement (w/c) ratio. three w/c ratios (0.40, 0.45 and 0.50) were used and for each w/c ratio three mixtures were prepared with cement contents 350, 400 and 450 kg/m3. the compressive strength, electrical resistivity and chloride diffusivity of t...

in this study, the effect of cement content on concrete performance in corrosive environments is investigated on concrete mixtures having the same water/cement (w/c) ratio. three w/c ratios (0.40, 0.45 and 0.50) were used and for each w/c ratio three mixtures were prepared with cement contents 350, 400 and 450 kg/m3. the compressive strength, electrical resistivity and chloride diffusivity of t...

Cement bonded particleboards were manufactured from hornbeam (Carpinus betulus L.) wood particles. Hydration tests were carried out to determine the inhibitory index in order to characterise wood-cement compatibility. The results revealed that the mixture of hornbeam -cement can be classifi ed as moderate inhibition. Two wood: cement ratios were applied in this study, namely 1:3 and 1:4, for th...

In cement-based pastes, the relationship between the complex phase assemblage and mechanical properties is usually described by the "gel/space ratio" descriptor. The gel/space ratio is defined as the volume ratio of the gel to the available space in the composite system, and it has been widely studied in the cement unary system. This work determines the gel/space ratio in the cement-silica fume...

Six different tetracalcium phosphate (TTCP) products were synthesized by solid state reaction at high temperature by varying the overall calcium to phosphate ratio of the synthesis mixture. The objective was to evaluate the effect of the calcium to phosphate ratio on a TTCP-dicalcium phosphate dihydrate (DCPD) cement. The resulting six TTCP-DCPD cement mixtures were characterized using X-ray di...