This paper presents the approach for the assessing of the operational reliability of a multi-layer thick-walled tube made of Rubber with textile reinforcement. The analysis of the fatigue accumulation process is carried out within the framework of the concept of the continuum mechanics of damage. The mathematical model, which takes into account the accumulation of damages in case of a random spread of the strength characteristics of the material, as well as the process of stochastic aging for the elastomeric matrix of the composite and possible random variation of the workload has been developed. In this case, the aging process is modelled as a reduction of the endurance limit of the material. In this paper, the mean equivalent strains of the tube and their possible statistical variation in operation have been investigated on the basis of the finite element method. To solve the above problems, a submodeling method has been employed in this work. The probability of non-failure operation of the tube has been determined using the methods and models proposed. The influence of the rate of the aging process on the lifetime of the tube has been estimated.

Introduction: The aim of this study is evaluation of efficacy of lacrimal sac localization with lacrimal probe without using light pipe. The study was based on nonrandomized prospective clinical trial with one year follow up period.Methods: A group of 40 patients operated since march 2001 to December 2004 The operation was Endoscopic Dacryocystorhynostomy and localization of lacrimal sac, which was performed with a lacrimal probe inserted in lacrimal sac. With pushing the probe inferomedialy pierces lacrimal sac lacrimal bone, and nasal musca over the bone. Follow up includes symptom evaluation such as epiphora and endoscopy. Success was defined as relief of symptoms & duct patancy with irrigation for a 1 year period.Results: 29 patients were male (72.5 %) and 11 were female (27.5 %). Mean age was 37.5 (with SD±12.26) in 20 patients right eye involved, left eye involved in 16 cases and in 4 cases both eyes involved. For 3 patients septoplasty was done besides EDCR. success rate was 82.5% and no complication was seen.Discussion: the use of lacrimal probe for lacrimal sac localization is a safe and easy method and don't have light pipe limitations then can replace light pipe.

Annually, thousands of tons of Rubber tires are produced, consumed, and discarded within the country. In recent decades, researchers have investigated the use of Rubber fibers or Rubber crumbs in concrete and their effects on its mechanical properties. However, the simultaneous utilization of both these materials as substitutes for sand and gravel in concrete has not been thoroughly explored. In this research, this research gap is addressed by examining the results of slump tests on Rubber concrete specimens with water-to-cement ratios of 0.45, 0.50, and 0.55, incorporating Rubber crumb and Rubber fibers up to 25%. The test results indicate a reduction in compressive strength with increasing Rubber content. By using different water-to-cement ratios, various Rubber concrete proportions, and the SIMAPro software, it was determined that the combination of Rubber crumb and Rubber fibers leads to approximately a 40% reduction in carbon dioxide emissions in the environment. The optimal condition for all ratios is achieved by adding 4% Rubber crumb and Rubber fibers.

In this study (Winter, 2007), the changes of histamine content as chemical parameter of spoilage was monitored in the muscle tissue of whole croaker (Otolithes Rubber) during ice storage for a period of 18 days (0, 3, 6, 9, 12, 15 and 18th day). Histamine was not detected in the first and 3rd storage days. The first detection of histamine was in the 6th storage day. Initial concentration of histamine was 1.49mg/g and finally reached 14.21 mg/g. Results showed that the concentration of histamine increased linearly (P<0.05) during ice storage (Except day 15). According to the results of this research, the mean concentration of histamine (mg/g) was found less than permissible limits of international standards.

Bitumen in pure form is not suitable for modern roads and present traffic. This has forced engineers to modify bitumen to improve its performance during service life. Two routes are known for bitumen modification, that is chemical and physical modifications. Therefore, there are chemical and physical modifiers. Among physical modifiers, polymers (thermoplastics, Rubbers and thermosets) are the most interesting ones. Rubbers are very good bitumen modifiers. In this work non-vulcanized Rubbers were incorporated into bitumen. The resulting blends showed better high and intermediate performance compared to the base bitumen. The improved properties are lower penetration and higher softening point. The low temperature properties such as Frass breaking point were not improved. New formulae for estimating bitumen’s performance using the results of conventional Frass and ring and ball tests were introduced. The morphology of the blends, depending on the rheological properties and compatibility of the Rubber with bitumen, was different. Polybutadiene formed a continuous phase mixture in bitumen. This was observed due to the compatibility of this Rubber with bitumen. Due to lesser compatibility between polymer and bitumen, SBRs and natural Rubber formed polymeric inclusion dispersed in bitumen.

Scrap Rubbers can be reclaimed, processed and crosslinked. But, because of the wide use of synthetic Rubbers in making many products and the absence of scrap Rubbers, reclaim Rubbers do not play an important role in Rubber industry. They are however used in specific applications. Therefore, it should be mentioned that the main motivation behind this study has been to make a survey on its economic feasibility, application fields and finally, to tackle the problem of environmental pollution. In this paper, reclaimed Rubber substitution for NR, SBR and BR with carbon black in cars' light weight tire manufacturing has been studied, and the optimum and favoured properties for static use items have been reached.

To divert water from a large diameter irrigation pipeline to a smaller diameter plastic gated pipe so called "Hydroflume", a pipe turnout was designed and built in the Sugar cane development and Byproducts Company with the cooperation of the Shahid Chamran University, Ahwaz, Iran. This pipe turnout not only conveys water but it also dissipates the excess energy. The structure has of a circular broad crested weir for measuring flow discharge. It also was equipped by a piezometer to facilate flow measurement. The turnout consists of two 800-millimeters precast concrete pipe and has been designed in such a way that can be produced in large quantities in the factory and then installed in the farm. In this paper the design criteria including: investigation of various alternatives and selection of the best type, hydraulics and structural design, laboratory and field tests are presented.

Double-pipe heat exchangers are commonly used in various industries, including power plants, solar cells, refineries, and automotive. The double-pipe heat exchanger is one of the most used simple exchangers in the industry. In this study, we employ computational fluid dynamics to investigate the flow characteristics of nanofluids within a double-pipe heat exchanger featuring a square inner tube and a circular outer tube (SC). The simulations are conducted under constant heat flux conditions, exploring laminar and turbulent flow regimes. Numerical results for water flow under forced convection are compared with reference results for validation. The results indicate that as the Reynolds number increases, particularly in turbulent flow regimes, the Nusselt number in nanofluid flow increases more than in water flow. For instance, in the case of aluminum oxide nanofluid flow at a Reynolds number of 500, the Nusselt number demonstrates a nearly 5% enhancement over water flow. In contrast, at a Reynolds number of 20000, this enhancement escalates to approximately 20%. Three types of nanoparticles are considered to investigate the effect of nanoparticle type on heat transfer and pressure drop. The results show that the use of nanoparticles has a slight effect on the friction factor while significantly enhancing heat transfer.

In order to evaluate the feeding habits of tiger-toothed croaker (Otolithes Rubber) 239 specimens were collected during December to March, 2003 in coastal areas of Chabahar, Iran. Stomach contents were examined by using of the numerical method. The abundance and frequency percents and type of preys, along with the percentage of emptiness of stomach, and prey dominant were evaluated during different months and in different groups based on upon length, sex and maturity. Result showed that in tiger-toothed croaker prey fish was the dominant and specific food item. There were monthly changes in feeding intensity and the feeding was weak. The percentage of emptiness stomach in March and December were highest and lowest, respectively. The empty stomach index (CV) indicated that tiger toothed croaker belong to the fish group with medium food intake. Shrimp was the main food in immature fish and with increasing in length and maturity of fish; shrimps were replaced with fish prey as the main food.