In this study, possibility of the use of four kinds of chemicals namely a monoammonium phosphate and diammonium phosphate, ammonium sulphate and mixture of Monoammonium phosphate and borax (70:30) as fire retardants with 12% concentration for Iranian beech wood(Fagus oriental is Lipsky) was surveyed. Wood samples were prepared according to JISA-1322 standard. To make wood samples fire retardaning, they were impregnated with dipping and Lowry methods. Impregnated samples with diammonium phosphate by Lowry method have the best fire resistance properties. These samples have 143%less in weight loss, 77.96%less in fire point, 67.93%less in duration flow after removing the burner and 54.83% less in percent of carbonization in compared with control samples. Wood samples impregnated by diammonium phosphate have highest compression strength parallel to grain; hardness and samples impregnated by ammonium sulphate have the least total shrinkage.

Kiwifruit softening and the spread of gray mold on the fruit are the most important factors to be considered in Kiwifruit storage life. In this study, the effect of calcium chloride (0, 1, 2, 4 and 8 percent) for 2, 4 and 8 minutes of dipping time were examined to improve the fruit physicochemical characteristics. Following fruits being dried (24 hours), they were stored at 0.5oC and 85-90% RH for 18 weeks. Samples were taken at 6th, 12th and 18th weeks and subsequently measured in some triats including water loss, firmness, TSS, TA, TSS/TA, pH, L* and a* values of color indices and ascorbic acid in comparison with control. Results showed that the fruits immersed in 4 and 8 percent of CaCl2 solution for 4 and 8 minutes had the highest firmness (3.4 kg). Water loss in control fruits was recorded higher (0.3 kg) than in all CaCl2 treatments. PH and TA parameters did not show significant changes during storage. Due to decrease in TSS through CaCl2 application, there occurred a significant difference in TSS/TA ratio. A positive relationship was observed between the L* value (47 value) and firmness especially when 2, 4 and 8 percent of CaCl2 were applied. In general, ascorbic acid increased in both control and CaCl2 treated samples but it was recorded higher in control during storage. In conclusion, CaCl2 treatments increased fruit quality and storage life due to inhibition of TSS increase and continuous firmness.

BACKGROUND: Contagious and environmental bacteria are current causes of mastitis and Bulk Tank Bacteria Count (BTBC). Beside other hygienic procedures related to controlling mastitis, Post-Milking Teat Dipping (PMTD) with a suitable teat antisepsis has a special place and can play an important role in the kind of herd mastitis and decreasing the Total Bacteria Count (TBC). OBJECTIVES: This study was performed to evaluate the efficiency of short-time changing of PMTD solution on count and kind of milk tank bacteria. METHODS: This study was conducted in 2 large dairy farms that their current antisepsis was iodophor components in 4 periods around Tehran during March to August 2010. In each 4 periods after the last time that iodophor was used, milk transfer tank sample was collected and 3 tests include Bulk Tank Somatic Cell Count (BTSCC), milk quality tests and bacterial isolation were performed. Then, antisepsis was replaced with chlore components for at least 2 weeks. At the end, another milk tank sample was obtained and tests were done again. RESULTS: Sectional changing of iodophor with chlore components in all 4 periods, according to decreasing in TBC, Coliform count, preliminary incubation count, laboratory pasteurized count, Staphylococcus count and Streptococcus count caused increasing the quality of milk and decreasing the mastitis. CONCLUSIONS: Changing in post-milking teat dipping has positive effect on quality of raw milk.

In this paper, a new method is described for the preparation of hydrophobic silica nano-coating on glass surfaces at room temperature, by applying tetrametoxysilane (TMOS) as a precursor and octadecyletrichlorosilane (OTS) as a surface modifier through a dipping method. By changing the mole ratio of OTS/TMOS, the efficiency of surface hydrophobicity modifies with coating. The best coating performance was obtained for NH3, OTS, TMOS, and MeOH with mole ratio of 8: 1.4: 1: 14.8, respectively. The water contact angle by of the hydrophobic glass surface reaches to 132 degree. Nano coating particle sizes is estimated to 2-29 nm by the DLS method. Experimental results show that hydrophobic silica film retains its hydrophobicity up to 200oC, but at higher temperatures loses this property. Besides determination of contact angle and particle size distribution, prepared nanoparticles are characterized by UV-Vis, FT-IR and TEM methods. Applying both TMOS and OTS and achieving water contact angle of 132 degree for modified glass surfaces are the novelties of this work.

Introduction: Dipping technique is commonly used by dental technicians to color zirconia ceramics; however, its impact on the bond between zirconia and resin cements is unclear. This in vitro study aimed to evaluate the microtensile bond strength (µTBS) between a zirconia ceramic and Panavia F2.0 resin cement after dipping in coloring liquids with different shades.Materials and Methods: Twenty zirconia blocks were dipped in four different shades of coloring liquids including A3, B2, C1, and D4, while five blocks were not colored for the control. All zirconia blocks were cemented to corresponding composite blocks using Panavia F2.0 resin cement. Zirconia-cement-composite blocks were cut into one hundred microbar specimens (1×1×10 mm). The specimens were divided into five studied groups according to their shade (A3, B2, C1, D4, control) and were subjected to an aging process. A microtensile tester applied tensile forces to the specimens, till the fracture occurred, and measured the mTBS values. One-way ANOVA and Tukey’s Post Hoc were used to analyze the data (P<0.05). Optical microscopy and scanning electron microscopy were employed to evaluate failure modes and surface structure.Results: The µTBS values for the groups showed significant differences (P<0.0001). D4 had the highest, and B2 had the lowest µTBS values. C1 (P=0.69) and A3 (P=0.89) showed no significant differences in the µTBS values compared with the control. Failure modes evaluation represented the lowest rate of adhesive failure for D4 (10%), and the highest in this respect for B2 (80%).Conclusion: Depending on the shade of coloring liquids, dipping had positive, negative, or no effects on the mTBS of zirconia ceramic to Panavia F2.0 resin cement.

Drilling is one of the most expensive stages of open pit mining and has more complexity. In drilling process many Parameters influence simultaneously, where studying each parameter requires recognition of the effects of the characteristics of the rock mass and its material. In this paper, the main aim was directed to investigate the joints dipping among the structural parameters of the rock mass. In the course of study, geometrical condition of penetration and transition of drill bit from joint surface were analyzed and different conditions of dips considered mathematically. This was followed by physical modeling of each of the geometrical conditions and penetration rate of cross bit measured by using rotary drilling system. Based on the numerical results obtained from experiments, mathematical equation between angles of joint dip with respect to drilling prolongation and penetration rates was presented. Furthermore, in conformity with the presented equation, by decreasing relative angle of joints dip, penetration rate of drill bit in jointed rock masses decreases linearly.

Objectives: Studies on the effect of coloring procedures on the bond strength of zirconia to resin cement are lacking in the literature. This study evaluated the effect of dipping of zirconia ceramic in different liquid color shades on the microtensile bond strength (MTBS) of zirconia ceramic to resin cement.Materials and Methods: This in vitro study was conducted on 100 microbar specimens divided into five groups of B2, C1, D4, A3 and control (not colored). To prepare the microbars, 20 white zirconia ceramic blocks, measuring 5×11×11 mm, were dipped in A3, B2, C1 or D4 liquid color shades for 10 seconds (five blocks for each color shade) and five blocks were not colored as controls. All the zirconia blocks were sintered in a sintering furnace. Composite blocks of similar dimensions were fabricated and bonded to zirconia ceramic blocks using Panavia F 2.0 resin cement. Zirconia-cement-composite blocks were sectioned into microbars measuring 1×1×10 mm. The MTBS of microbars was measured by a testing machine. Data were analyzed using one-way ANOVA and Tukey’s test. All tests were carried out at 0.05 level of significance.Results: Statistically significant differences were found among the groups in MTBS (P<0.001). The D4 group had the highest MTBS value (39.16 ± 6.52 MPa).Conclusion: Dipping affected the MTBS of zirconia ceramic to Panavia F 2.0 resin cement; however, a similar pattern of change was not seen due to the different liquid color shades.

Metallic coatings increase corrosion and oxidation resistance of steel. Aluminum coating is one of the most effective methods and hot dipping is the most economic one. This process is known aluminizing. In this research, aluminized layers were studied by optical microscopy, metallographic methods, microhardness, x-ray diffraction (XRD) and electron probe micro analyzer (EPMA). The properties of aluminized coating evaluated by bending, .oxidation and corrosion tests.