introduction: the aim of this study was to compare the chemical compounds of white proroot mineral trioxide aggregate (wmta) hydrated at different ph environments. methods and materials: mixed samples of wmta were kept in acidic (ph=5.4), neutral (ph=7.4) and alkaline (ph=9.4) environments for 48 h. then, x-ray diffraction (xrd) analysis was performed for both hydrated and powder forms of wmta....

hydrogels, due to their unique potentials such as high-water content and hydrophilicity are interest for the controlled release of drug molecules. the present study aims to create a controlled-release system through the preparation and characterization of hydrogels based on ph-sensitive polymers such as poly (acrylic acid). poly (acrylic acid), p(aa), hydrogel has been synthesized by radical po...

o bjectives: the purpose of this study was to evaluate the effect of salivary ph on the shear bond strength (sbs) of orthodontic brackets to tooth surface. materials and methods: eighty intact premolars were randomly divided into four groups of 20.  after bonding a bracket on each tooth, the groups one to four were stored in artificial saliva at a ph of 3.8, 4.8, 5.8, and 6.8, respectively for ...

objective(s) in this study, a kind of ph sensitive composite membrane was prepared and drug permeation through it was investigated in terms of ph. rationale of this study originated from the fact that a ph change which may be a result of a disease state in the body can trigger drug release. materials and methods  here, a kind of ph sensitive composite membrane containing different nanoparticle ...

removal of thiosulfate (s2o32-, 200 mg/l) from simulated wastewater samples was investigated under varying co-pollutants and ph conditions employing the titanium dioxide (tio2) mediated photocatalysis. for thiosulfate only studies higher substrate removal was noted at lower ph with a specific trend of ph 4 > ph 7 > ph 10. furthermore, near complete thiosulfate removal was also achieved at ph 4....

the present study was carried out in order to test the effect of grapevine rootstocks root growth on biomass and leaf nutrition status in extreme soil conditions. own rooted cuttings of rootstocks fercal, teleki kober 5bb, georgikon 28 and four new rootstock hybrids from the breeding program of georgikon faculty, hungary (fb01, jb01, zamor 17 and szf10) were grown 3 months in pots. the 5 l pots...

the main reasons for the fixation of some elements and consequently nutrient deficiencies, especially phosphorus, iron and zinc, are high levels of calcium (calcareous soils) and soil ph. two sulfur fertilizers (sulfur alone and sulfur + organic material + thiobacillus spp.) with two rates (2 and 4 kg sulfur/tree) were used to decrease soil ph and availability of p, fe and zn in apple trees dur...

steady state and dynamic fermentations of baker's yeast in molasses based media were analyzed in a laboratory scale bioreactor. sugar and biomass balances together with the monod biokinetics were used to develop the process model. parameters of the model were obtained using collected experimental data. model predicted open loop responses to step changes in feed concentration as well as dilution...