In order to improve particle PROPERTIES, new processes combining granulation and crystallization are being developed. This work deals with the spherical crystallization process by the quasi-emulsion mechanism applied to carbamazepine, a pharmaceutical drug. The aim of the present study was to produce of spherical grains made of mall crystals of a drug that have adequate PROPERTIES for direct compression when manufacturing tablets. Crabamazepine was crystallized under different conditions and the obtained spherical crystals were examined in terms of flow PROPERTIES, particle size analysis, and compression and dissolution behaviors. Physical characteristics of the crystals were studied for the morphology of crystals using scanning electron microscope, for the identification of polymorphism by x-ray powder diffraction and for thermodynamic PROPERTIES using differential scanning calorimetry. The results showed that the agglomerates produced at 5oC under stirring rate of 300 rpm had superior flow than other agglomerates. Further more the results suggest that agglomerates flow and pack smoothly from the hopper into the die and that tablets formed from agglomerates attain uniformity in weight due to spherical shape of the treated samples. The results showed that, generally, the treated carbamazepine samples (agglomerated forms) possessed superior mechanical and better dissolution rate characteristics to untreated crystals. The results of DSC and x-ray showed that untreated sample and agglomerates were form III and form I of carbamazepine respectively.

Objective: This study evaluated the effect of incorporating 1 wt% egg shell powder (ESP) into Biodentine™ (BD) on its PHYSICOMECHANICAL PROPERTIES. Methods: Chicken eggs were ground and sterilized. Then, one wt% ESP was added to BD powder and mixed with BD liquid. The mixture’s pH and solubility were measured on 1, 3, 7, and 28 days. The setting time was determined using a Gillmore needle. Compressive strength was measured using a universal testing machine after 1 and 14 days. Surface chemistry was analyzed via FTIR spectroscopy. The findings were compared by independent samples t-test, the repeated measures ANOVA, and the Bonferroni post-hoc test (α = 0.05). Results: pH levels were comparable between the groups (P > 0.05). BD-ESP had a higher setting time than BD (P < 0.001). BD-ESP solubility was significantly higher than BD on day 1 (P = 0.001) but lower on days 7 (P = 0.006) and 28 (P = 0.001). On day 1, BD had higher compressive strength than BD-ESP (P = 0.027), whereas the compressive strength of both groups was comparable on day 14 (P = 0.099). FTIR analysis revealed an additional IR band associated with the phosphate band in the BD-ESP group, suggesting new apatite formation. Conclusions: Incorporating 1% ESP into BD resulted in lower initial solubility but higher solubility after a week and a month, likely due to increased ion dissolution. ESP incorporation also promoted additional apatite formation but negatively impacted the setting time and initial strength of BD.

Thorough knowledge of PHYSICOMECHANICAL PROPERTIES of rocks is crucial during the primary and secondary stages of designing a rock engineering project. Laboratory examination of these PROPERTIES requires high-quality rock specimens. However, preparing such high accuracy samples is a difficult, expensive, and time-consuming task, especially in weak and fractured rocks. Hence, indirect approaches seem an attractive research area for determining these PROPERTIES. The main object of this study is to develop some empirical relations to determine different physical and mechanical PROPERTIES of sedimentary and metamorphic rocks based on the shear wave velocity index. To do that, several schist, phyllite, and sandstone core samples were collected from the drilled boreholes in the Marivan Azad dam in western Iran. Then, the shear wave velocity and some physical and mechanical PROPERTIES of rocks were measured in dry and saturated conditions. Subsequently, statistical analyses were conducted to develop shear wave velocity-based equations to determine different rock PROPERTIES, including uniaxial compressive strength, modulus of elasticity, porosity, Poisson’, s ratio, slake durability index, density, and water absorption. An equation with the maximum correlation coefficient was proposed as the optimum equation to determine each of the above rock PROPERTIES. Finally, the results of the proposed empirical equations were compared with those of laboratory measurements. This comparison proved the proposed equations to have high accuracy for determining the PHYSICOMECHANICAL PROPERTIES of rocks and can be used in practical projects with similar geological conditions to save time and money.

Introduction: A systematic review and meta-analysis were conducted to evaluate the PHYSICOMECHANICAL PROPERTIES of tertiary monoblock obturation with different obturation techniques. Methods and Materials: PubMed (MEDLINE), Web of Science, Scopus, the Cochrane Library, LILACS, IBECS, and BBO were searched time. PICO question was: “ In extracted human teeth (Population), does tertiary monoblock obturation (Intervention) have superior PHYSICOMECHANICAL PROPERTIES (Outcome) compared to conventional obturation systems (Comparison)? ” . Statistical analyses for push-out bond strength were performed with RevMan software by comparing the mean differences of each study, with a 95% confidence interval. Inverse variance was used as statistical method, random-effects models as analysis model, and heterogeneity between studies was assessed by Cochran’ s Q test and I2 statistic (P  <0. 05). Results: Of 2162 studies retrieved, 31 were included in this review for “ Study Characteristics” . Ten studies were included in the meta-analysis. Analysis demonstrated that conventional obturation had significantly higher push-out bond strength than tertiary monoblock obturation (P  <0  . 01), with a mean difference of − 1. 00 (95% CI, − 1. 41 to − 0. 58; I2=100%). Subgroups using single-cone and cold lateral condensation techniques showed significantly lower push-out bond strength for tertiary monoblock obturation (P  <0. 01), respectively with a mean difference of − 0. 09 (95% CI, − 1. 13 to − 0. 67; I2=97%) and of − 1. 97 (95% CI, − 3. 19 to − 0. 75; I2=100%). The warm vertical compaction subgroup showed no statistically significant difference between tertiary monoblock and conventional systems (P  =0. 13), with a mean difference of 0. 49 (95% CI, − 0. 14 to 1. 12; I2=10%). Conclusion: Tertiary monoblock systems have a push-out bond strength similar to conventional systems when used with warm vertical compaction.

Background and the purpose of the study: Mechanical PROPERTIES of films prepared from aqueous dispersion and organic solutions of Eudragit RL were assessed and the effects of plasticizer type, concentration and curing were examined.Methods: Films were prepared from aqueous dispersion and solutions of Eudragit RL (isopropy alcohol-water 9: 1) containing 0, 10 or 20% (based on polymer weight) of PEG 400 or Triethyl Citrate (TEC) as plasticizer using casting method. Samples of films were stored in oven at 60oC for 24 hrs (Cured). The stress-strain curve was obtained for each film using material testing machine and tensile strength, elastic modulus, %elongation and work of failure were calculated.Results and major conclusion: The films with no plasticizer showed different mechanical PROPERTIES depending on the vehicle used. Addition of 10% or 20% of plasticizer decreased the tensile strength and elastic modulus and increased %elongation and work of failure for all films. The effect of PEG 400 on mechanical PROPERTIES of Eudragit RL films was more pronounced. The differences in mechanical PROPERTIES of the films due to vehicle decreased with addition of plasticizer and increase in its concentration. Curing process weakened the mechanical PROPERTIES of the films with no plasticizer and for films with 10% plasticizer no considerable difference in mechanical PROPERTIES was observed before and after curing. For those with 20% plasticizer only films prepared from aqueous dispersion showed remarkable difference in mechanical PROPERTIES before and after curing. Results of this study suggest that the mechanical PROPERTIES of the Eudragit RL films were affected by the vehicle, type of plasticizer and its concentration in the coating liquid.

Different activator systems containing zinc oxide, zinc stearate, calcium oxide, thiodiglycol metal complexes and nano-zinc oxide were applied for sulphur vulcanization of NR/SBR blend. The systems were chosen in order to have better dispersion in rubber matrix, better metal ion release in vulcanization process and lower zinc content. The cure characteristics and PHYSICOMECHANICAL PROPERTIES were investigated. Results showed that zinc oxide could be reduced from 4 to 2 phr in the formulation, without any detrimental effects on PROPERTIES. Zinc stearate was not a good activator but it could be employed in combination with zinc oxide to improve tensile PROPERTIES. Calcium oxide did not show satisfactory results. Zinc complex of thiodiglycol was an acceptable substitute for zinc oxide due to better dispersion in rubber matrix and better ability for zinc ion release. Zinc content could be reduced to about 4.5 mmol per 100 g of rubber by using this complex. Calcium complex of thiodiglycol was not a good choice either and showed detrimental effects on PROPERTIES. Application of nano-zinc oxide did improve abrasion and tensile PROPERTIES due to better surface effects. An alternative mixing method which was used to improve the zinc oxide and nano-zinc oxide dispersion was good and showed better abrasion and tensile PROPERTIES. The results are presented as patterns to achieve the desirable PROPERTIES.