نشریه صنعت لاستیک ایران
پیاپی 83 (پاییز 1395)

Producing of polymeric nanocomposites due to their remarkable properties in comparison with polymer composite or polymer blends is highly attentioned in recent years. Measuring of physical, mechanical and rheological properties of nanocomposites as their final properties is time consuming and costly. Nowadays, prediction of these properties via using intelligent technique has received attention, because of shortening the time of properties measurement and economic efficiency. In this research, Artificial Neural Network (ANN) method is applied to predict the storage modulus, complex viscosity, tensile strength and abrasion of natural rubber/clay nanocomposite. The predicted results show a good agreement with experimental data.

A definition of macromolecular science (as opposed to polymer science and engineering) is given, from which the year 1930 is derived as the year of its birth. The scope of treatment of this paper will be limited to solid technical polymers. Some important discoveries of polymer technology in the nineteenth century are reviewed together with the reason why the concept of macromolecules and the theory of rubber elasticity did not emerge earlier. The role of chain backbones in structure formation and mechanical loading of technical polymers has been heavily discussed ever since and has attracted this author for most of his scientific work. He offers a personal perspective of the most important achievements in three domains of macromolecular science: the synthesis of well-designed chain molecules, structural characterization and the understanding of the micro-mechanics of (nano-structured) polymer materials. Progress is generally documented by citing individual references from the discussed periods— well knowing that the development of science is due to the contributions of many more people. In conclusion, a critical outlook will be attempted on future trends in the design and application of well-adapted—and frequently complex—polymer systems towards growing human needs.

The squeezing rolls of steel pickling are concerned due to hard working conditions such as acidity and high pressure. In this study, is devoted to the investigation on the use of nano silica particle on the mechannical properties of NR/SBR compound. A reference compound was first designed in wich 60 phr carbon black was used as the reinforcing filler. Six sample based on this compound were prepard using two different types of nano silica with 8 and 13 percent of coupling agent. The mechanical and curing peroperties were measured on appropriate samples made frome these compound to determine tensile strength, elongation at brake, abrasion resistance, hardness, Tear resistance, compresion set and rheometery parameters. The results indicated that the compound containing NS.V3.NOP nano particle due to lack of any modifier has the lowest tensil and abrasion resistance. To achieve improvement in mechanical properties, modified nano-silica (NS.V3.13P, NS.A4.13P)were usedand best results (high tear resistanse, high abrasion resistance and high tensile strength) were obtained.The results obtained of Squeezing roll performance which is produced with compound including nano silica indicated significant improvement with double longevity that were confirmed the result of experiments.

According to industry developments in recent decades with the rise in unit quality control and instrumentation engineering for product quality measurement unit, various methods is used for quality control. Review and evaluate the quality of tires in the production of particular importance is the need, because it is the most important piece of safety in cars. Common procedure for measuring the quality of tire produced in the Iran tire industry is the dynamic tests which is very useful but the image processing algorithms are more useful and more optimzed. For porpuse of using these methods, raw pictures should be captured. Lots of modules can be used in this process like X-ray or visible radiations and infrared ones. These two methods has some drawbacks due to human eyes which other procedures should be implemented. In this paper a novel algorithm for detection and classification of car tier defect is propsed. In this algorithm, first X-rays pictures are captured then Kenni image processing algorithm and mathematical mophology is applied on them. This method is offered for the first time which has a better anwer than previous methods.

The aim of this paper is to design a comprehensive roles and responsibilities inventory for marketing managers, from which it identifies for the role of marketing and market management in corporations. The role inventory of the marketing manager listed using content analysis on online job announcements. The findings of this paper reveal that marketing managers are responsible for six critical role dimensions in the organization. Dedicated roles of marketing managers in the management of marketing mix elements are for the management of promotion-related activities. Communicational and relational (internal and external) roles are the most frequently addressed of marketing managers’ responsibilities. Development and influence of market and marketing knowledge into the company’s value network is another of the major role dimensions. Increasing financial pressures on companies mean that the results of marketing activities must be measurable, so developing financial indicators and performance analysis for marketing activities has become an important part of the manager’s agenda. The paper is the first attempt to develop a role inventory for the marketing managers including proofs, signals, and insights from the practice.

The relationship between job satisfaction and organizational commitment is one of the most important and essential issues in management. The concepts of “job satisfaction “and “organizational commitment “have particular significance because of employee’s sensitive role as human capital of organizations ,on the othet hand, regarding the key role of Sapco in Iran khodro’s chain of supply , its changes bear a considerable importance. Improvement of job satisfaction is accompanied by improving of organizational commitment. This research is following the identification of components of employee’s job satisfaction and its relations with organizational commitment. The main question of this research is: Is there a meaningful relation between job satisfaction and organizational commitment according to employees of target population or not? Organizational commitment is accordance with Allen &Meyer model as a template which includes three components: sympathy commitment, continuous commitment and normative commitment. Job satisfaction’s evaluation with using smith, Kendal and halin’s model including five components as: supervision elements, job elements, organizational elements, salary and benefits and communication among colleagues are examined. Statistical population of this research is the total employees of Sapco Company (Iran Khodro’s Supplying Automotive Parts Company) including about 1388 person and according to Cochran’s formula which has chosen 300 samples for implementing research, but it increases about 435 samples . The Tools of gathering data are questionnaires and for analyzing data, descriptive statistic methods as frequency distribution, percentage, mean, standard deviation have been used and for the inferential statistic: skewness, kurtosis, Histogram, Anova test, Spearman correlation coefficient test , Regression analysis have been used.