The final hot strip profile is a superposition of the roll INITIAL CROWN, the roll bending and flattening CROWN, the roll wearing CROWN and the roll thermal CROWN. In this research, linear regression models are proposed to predict the roll force, the roll wearing CROWN and the roll thermal CROWN using experimental data provided by Mobarake Steel Complex (MSC). The Euler-Bernoulli beam theory based on elasticity approach is also used to predict the roll bending and flattening CROWN. Finally, the work roll INITIAL CROWN in order to obtain desired strip profile in hot rolling is predicted utilizing a computer programming. The obtained INITIAL CROWNs are then used for seven stands of an actual roll schedule for hot strip mill of MSC. The measured strip profile shows a good agreement with the desired one for the mentioned mill.

One of the important issues in the production of concrete is environmental variability that affects the concrete and elements constructed from this material. Due to the importance of different characteristics of concrete in short- and long-term conditions, this article aims to investigate the influence of INITIAL temperature conditions of self-compacting concrete on its long-term characteristics and determine the INITIAL optimal temperature of concrete. For these purposes, several experiments under three temperature conditions of 5, 20, and 40 degree-of-Celsius were conducted to evaluate the rheology and mechanical properties of fresh concrete in the range of 7 and 28 days. In these experiments, alternative mineral admixtures of cement such as micro-silica, fly ash, and zeolite were used to build the concrete specimens. Results demonstrate that the mechanical properties of the specimens increase with increasing INITIAL temperature in the short term, while such properties significantly decrease in the long term compared to the specimens constructed under lower INITIAL temperature. Moreover, the fluidity of self-compacting concrete increases with increasing INITIAL temperature.

Liens tolerate environmental stresses utilizing is one of the applicable technologies in sustainable agriculture. Since occurrence of a suitable winter for studing and selection of cold/frost resistance on breeding materials is one year out of ten, therefore laboratory methods complementing field data provide a reasonable solution for this propose. This research was conducted in Khorasan Agri. Res. Center. Mashhad. Using RCBD in three replications during 1380-81. Treatments consisted of twenty promising genotypes of uniform regional yield trail (cold area). Genotypes suits low temperature regions will be introduced based on generated results from this investigation. Using CROWN freezing method, experimental genotypes were treated with -20. C temperature under controlled conditions. Survival percentage was computed. Results indicated that genotypes No.9 (C-78-9) and No.7 (C-78-7) had highest (98.33%) and lowest (66.67%) survival percentage respectively. The minimum CROWN Moisture Content was detected in line No. 9 (C-78-9) and there was no significant difference for the same trait between genotype No.7(C-78-7) and other superior genotypes. A high negative correlation (r=-0.701) was observed between survival percentage after exposing to frost and CROWN moisture content. Ear primordia development stage was one of the characters which had also a significant correlation with survival percentage (r=-0.619). Significant correlation between survival percentage and days to heading (r=-0.207) and days to physiological maturity (r =-0.028) was not observed. Correlation between survival percentage and collected cold damage data from experimental fields over five low temperature regional stations was highly significant (r=0.416), therefore it may be concluded that CROWN Freezing Method and subsequent computing of survival percentage is a reliable method for estimating wheat frost/cold tolerance in natural conditions.

Background. Dental esthetic has become a popular topic among all disciplines in dentistry. There is a notable relationship between a person’ s attractiveness and amount of gingival show. Excessive gingival display and discrepant gingival margins has a negative impact on a pleasant smile and also on one’ s self-confidence. Esthetic CROWN lengthening is used to alter the gingival labial profile. This procedure is indicated to reduce gingival exposure or asymmetry between contralateral teeth. It is important to consider parameters of ideal gingival labial positions. Esthetic analysis that is included, facial, dental and dentogingival, should be done before beginning of treatment. The aim of this study is to review the related studies and gather information on esthetic parameters of ideal gingival labial positions and classification of CROWN-lengthening procedures. Methods. This study is based on articles found in PubMed database, published in 2014 and later. The keywords for this research were esthetic CROWN lengthening, gummy smile, gingivectomy, and periodontal surgery. Results. In order to perform a successful treatment, having the knowledge on classification and treatment sequence of CROWN-lengthening procedures with their indication and contraindications, is critical. Esthetic CROWN lengthening classification: I. Gingival reduction only without osseous resection II. Gingival reduction with osseous resection Both of these techniques can be performed by gingivectomy or apically positioned flap. This decision is made on the basis of amount of keratinized gingiva. Gingival reduction only is rarely used because bone reduction is usually needed to achieve ideal treatment. Conclusions. Dentists should be aware patients of benefits of cosmetic dental rehabilitation. The evaluation of each case is the most important step to achieve proper treatment plan and choose correct technique for CROWN Lengthening. Therefore, the patient esthetic demand will be perceived in the best way.

Background. Periodontal surgery has a major role in aesthetic dentistry. Main indications for aesthetic CROWN lengthening of anterior teeth are excessive gingival exposure or “ gummy smile” appearance, to expose the anatomic CROWN of teeth, reduce asymmetry between contralateral teeth, and reduce gingival exposure. The preservation of biologic width space following aesthetic procedures demands the existence of clearly defined therapeutic objectives Methods. Indications for surgery and different surgical techniques will be explained as well identifying the problem Results. Different indications are illustrated with cases to show the surgical treatment approach to improve the esthetic appearance for each condition. Conclusions. Aesthetic CROWN Lengthening is a predictable surgery.

Background and Aim: One of the most important criteria for clinical acceptance and longevity of cast restorations is marginal accuracy. Marginal discrepancy causes cement layer exposure, increases risk of cement wash out leading to plaque accumulation, recurrent caries and gingival tissue inflammation. This study assessed the effect of finishing line preparation design on marginal discrepancy.Methods & Materials: In this experimental invitro study, three metal dies were prepared using simulation method with beveled shoulder, chamfer and combination of both (buccal beveled shoulder encounters palatal chamfer) that addressed groups A, B and C respectively. Seven wax patterns for each die were cast in Wiron 99 (Basemetal Alloy).After seating the trameworks, marginal discrepancy was measured in two horizontal and vertical dimensions. The data were analyzed by one way ANOVA and Tukey multiple comparisons tests.Results: The significant differences of horizontal marginal opening were found among three groups in buccopalatal and mesiodistal directions (P<0.003, P<0.0001). Also, significant differences found between pair groups except to A and C in buccopalatal and A and B in mesiodistal directions. The vertical marginal opening in three groups was statistically different at mesial, distal and palatal directions (P<0.05) but not at buccal side. The vertical marginal opening differences of pair groups (A and C, Band C) at mesial, distal and palatal directions were significant (P<0.05).Conclusion: Within the limitation of this study, finishing line, preparation design significantly affects the marginal discrepancy, the least and most horizontal marginal opening was produced in beveled shoulder and the combined preparation of beveled shoulder and chamfer, respectively. Chamfer preparation caused minimum vertical marginal opening while the beveled shoulder was in the next rank with no significant statistical differences.

Azobenzo-10-CROWN-3 (8), azobenzo-13-CROWN-4 (9) and azobenzo-16-CROWN-5 (10) have been prepared. Reaction of o-nitrophenol with dibromides (2-4) gave dinitro compounds (5-7) in high yields. Azo-macrocyclization of these compounds with Zn/NaOH in ethanol gave azobenzo-CROWN ethers (8-10) in moderate yields.