Sample records for british rubber industry

  1. Treatment of wastewater from rubber industry in Malaysia ...

    African Journals Online (AJOL)

    Presently, Malaysia is the third largest rubber producer in the world, whereby the rubber industry is an economically and socially significant industry. Rubber industry consumes large volumes of water, uses chemicals and other utilities and produces enormous amounts of wastes and effluent. Discharge of untreated rubber ...

  2. The performance and risk of Kossan Rubber Industries Berhad


    teoh, kun youn


    The purpose of the study is to investigate the overall performance of Kossan Rubber Industries Bhd with internal factors and external factors on profitability performance. The data obtained from annual report of Kossan Rubber Industries Bhd during the years 2011 to 2015. The financial ratio used to measure the overall performance and risk of the company. The measurement of current ratio, return on assets (ROA), and inventory turnover are used to determine the overall performance and the effic...

  3. Genotoxic risk in rubber manufacturing industry: a systematic review. (United States)

    Bolognesi, Claudia; Moretto, Angelo


    A large body of evidence from epidemiological studies among workers employed in the rubber manufacturing industry has indicated a significant excess cancer risk in a variety of sites. The International Agency for Research on Cancer has recently classified the "Occupational exposures in the rubber-manufacturing industry" as carcinogenic to humans (Group 1). A genotoxic mechanism for the increased cancer risk was suggested on the basis of the evidence from the scientific literature. Exposure assessment studies have shown that workers in the rubber manufacturing industry may be exposed to different airborne carcinogenic and/or genotoxic chemicals, such as certain aromatic amines, polycyclic aromatic hydrocarbons, N-nitrosamines, although the available information does not allow to establish a causal association of cancer or genotoxic risk with particular substances/classes of chemicals or specific jobs. The aim of this paper is to critically evaluate, by conducting a systematic review, the available biomonitoring studies using genotoxicity biomarkers in rubber manufacturing industry. This systematic review suggests that a genotoxic hazard may still be present in certain rubber manufacturing industries. A quantitative risk assessment needs further studies addressing the different, processes and chemicals in the rubber manufacturing industries. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  4. Treatment of wastewater from rubber industry in Malaysia

    African Journals Online (AJOL)



    Sep 20, 2010 ... Review. Treatment of wastewater from rubber industry in. Malaysia. Mitra Mohammadi1, Hasfalina Che Man2*, Mohd Ali Hassan1 and Phang Lai Yee1. 1Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400. UPM Serdang, Selangor ...

  5. 29 CFR 1910.216 - Mills and calenders in the rubber and plastics industries. (United States)


    ... 29 Labor 5 2010-07-01 2010-07-01 false Mills and calenders in the rubber and plastics industries. 1910.216 Section 1910.216 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND... Guarding § 1910.216 Mills and calenders in the rubber and plastics industries. (a) General requirements— (1...

  6. Measurement of Noise Level in Enumeration Station in Rubber Industry (United States)

    Rizkya, I.; Syahputri, K.; Sari, R. M.; Siregar, I.


    This research was conducted in companies engaged in the production of crumb rubber. In the rubber industry, the potential noise occurs in the enumeration station. Stations enumeration use machine and equipment that potentially generated noise. Noise can be defined as an unwanted sound because it does not fit the context of space and time so that may interfere with the comfort and human health. The noise level measured at random during the initial observation station enumeration is 101.8 dB. This value has exceeded the Threshold Limit Value (TLV) Kep-51 / MEN / 1999 and SNI No. 16-7063-2004 so research must be done to measure the level of noise in the enumeration station. Quantitative methods used in the study. Observations made with the calculation method of equivalent noise level. Observations were made on six measurement points for one shift for three days. The results showed the noise level over the Threshold Limit Value is equal to 85 dBA/8 hours. Based on the measurement results, the whole point of observation was far above the threshold Limit Value (TLV). The highest noise level equivalent is in the observation point 6 with a value of 102, 21 dB.

  7. Rethinking Apprenticeship Training in the British Construction Industry (United States)

    Abdel-Wahab, Mohamed


    The British government continued intervention to support apprenticeship training across the economy has been notable in recent years. The construction industry is the only sector to retain a levy/grant scheme (that supports training including apprenticeships) since 1964, yet it still faces the problem of skills shortages. This article thus reviews…

  8. Greenhouse Gas Emissions from Rubber Industry in Thailand

    NARCIS (Netherlands)

    Jawjit, W.; Kroeze, C.; Rattanapan, S.


    Rubber production has been taking place in Thailand for many decades. Thailand is currently the world's largest natural rubber producer. We present emissions of greenhouse gases associated with the production of fresh latex, and three primary rubber products, including concentrated latex, block

  9. Rubber (United States)

    Graves, D. F.

    The word "rubber" immediately brings to mind materials that are highly flexible and will snap back to their original shape after being stretched. In this chapter a variety of materials are discussed that possess this odd characteristics. There will also be a discussion on the mechanism of this "elastic retractive force." Originally, rubber meant the gum collected from a tree growing in Brazil. The term "rubber" was coined for this material by the English chemist Joseph Priestley, who noted that it was effective for removing pencil marks from paper. Today, in addition to Priestley's natural product, many synthetic materials are made that possess these characteristics and many other properties. The common features of these materials are that they are made up of long-chain molecules that are amorphous (not crystalline), and the chains are above their glass transition temperature at room temperature.

  10. Pessimism Preserved: Real Wages in the British Industrial Revolution


    Robert Allen; Allen, Robert C.


    The paper compares Feinstein`s and Clark`s consumer price and real wage indices for the British industrial revolution. The sources for their weights and component price series are evaluated. While some of Clark`s innovations are improvements, many of his changes degrade the price index. A new price index is developed using the best components of Clark`s and Feinstein`s. This index is much closer to Feinstein`s than to Clark`s. The implied growth in real wages is also close to Feinstein`s and ...

  11. Pengaruh pupuk organik limbah padat industri crumb rubber terhadap pertumbuhan tanaman cabe (Capsicum frutescens

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    Full Text Available Abstract The research about the influence of organic fertilizer of crumb rubber solid waste industry on chili plants (capsicum frutescens growth had been done. The aim of the research was to evaluate the vegetative growth of chili plants treated with organic fertilizer that was made from crumb rubber solid waste industry and it was compared with chili plants treated was commercial organic fertilizer (SP -36. The organic fertilizer was made by mixing of soil, crumb rubber solid waste, cow fieces, talc, saw dust, and hull rices, using and aerab system. The variation of the amount of solid waste was 0%; 10%, 20%; 30%; and 40%, respectively. Fertilizing of chili plants was done by dasage variation i.e.1:1,5; and 2 kg/10m2 and control (without fertilizer respectively. The observation was done on fourth month on vegetative growth including high plants, leaf length, and leaf width. The results showed that crumb rubber solid waste could be used as organic fertilizer for chili plants. The best growth of plants especially high was treated with 20% crumb rubber solid waste at dosage of 2 kg /10m2 is 38.2 cm, while the best growth of leaf length and leaf width was chili plant treated with 40% crumb rubber solid waste at dosage of 2 kg/10m2 was 10.0 cm and 6.2 cm.

  12. Whither British labour law crisis, what crisis? an historical perspective on the juridification of British industrial relations


    Welch, Roger


    This paper is largely historical in that it reflects on the reasons why the British system of industrial relations was transformed from a system rooted in voluntarism or legal abstentionism to one which became increasingly juridified from the 1960s onwards. Juridification can be understood as a combination of judicial intervention in the arena of industrial conflict and the enactment of substantial legislation in areas previously left to employment contracts between employers and their employ...

  13. Exploration of Barriers in Achieving Proactive Environmental Strategies in a Natural Rubber Industry : A Case Study

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    Syarifa Arum Kusumastuti


    Full Text Available As the evolving of environmental issues over time, the development of environmental management approaches in industries began to shift to the prevention of pollution to reduce environmental impact. However, in practice, many obstacles encountered during the environmental management change to be more proactive. This study aims to explore the barriers of achieving the proactive environmental strategy in a rubber processing industry. Used a case study approach in a natural rubber processing factory, the data was collected through interviews with experts and sources as well as observation in the field. This study shows main barriers that faced by the company consist of financial issue, human resources, communities’ pressure, technological change and communication with environmental experts. The results of this study suggest conducting cooperation with research institutions or environmental experts especially for skills that cannot be controlled by the manager or employees in the company. 

  14. A case-control study of bladder cancer in the United States rubber and tyre industry. (United States)

    Checkoway, H; Smith, A H; McMichael, A J; Jones, F S; Monson, R R; Tyroler, H A


    A case-control study of bladder cancer was conducted in five United States rubber and tyre companies to determine if there were high-risk jobs and work areas within the industry. The study included 220 male cases of bladder cancer, of whom 107 were identified from hospital record reviews and 113 from death certificates. Each case was matched individually with two industry controls by sex, race, year of birth, and company. One control was matched additionally by year of hire and duration of employment. Comparisons of cases and controls not matched by year of hire and age of hire showed no differences for those variables, which suggests that age and calendar period of first exposure to the industry were not risk determinants. When the work histories of both cases and controls were contrasted it was found that cases were more likely than controls to have worked in milling (odds ratio (OR) = 1.91) and calender operation (OR = 2.21) jobs. The relative risk estimates for milling and calender operation both exhibited linear trends of increase with duration of exposure. Milling and calender operation jobs entail potential exposures to volatilised reaction products from heated rubber stock. A better understanding of aetiological associations with job type will require more detailed characterisation of the work environment with regard to the sources and levels of aromatic amines and other suspected bladder carcinogens. PMID:7272236

  15. Analysis of the British Industrial Revolution in cinema: Oliver Twist


    Fuente Diez, Óscar


    La Revolución Industrial británica fue un fenómeno histórico que incluso a día de hoy continúa atrayendo miradas. Sus dimensiones fueron tales que actualmente sus consecuencias aún son visibles. El objetivo de este proyecto es analizar el impacto social de la Revolución Industrial británica y las causas que llevaron a este punto como retrata Oliver Twist, la película seleccionada. Desde la perspectiva de las injusticias laborales y las desigualdades sociales, el estudio se centra en las conse...

  16. Constructing Learning: Adversarial and Collaborative Working in the British Construction Industry (United States)

    Bishop, Dan; Felstead, Alan; Fuller, Alison; Jewson, Nick; Unwin, Lorna; Kakavelakis, Konstantinos


    This paper examines two competing systems of work organisation in the British construction industry and their consequences for learning. Under the traditional "adversarial" system, conflict, hostility and litigation between contractors are commonplace. Such a climate actively militates against collective learning and knowledge sharing between…

  17. Wireless and empire geopolitics radio industry and ionosphere in the British Empire 1918-1939

    CERN Document Server

    Anduaga, Aitor


    Although the product of consensus politics, the British Empire was based on communications supremacy and the knowledge of the atmosphere. Focusing on science, industry, government, the military, and education, this book studies the relationship between wireless and Empire throughout the interwar period.

  18. Building “Sound” Industrial Relations in Nigeria: The British and ...

    African Journals Online (AJOL)

    This paper examines measures taken by the British colonial administrationin Nigeria during the early years of the Cold War. I posit that anti-leftistmeasures against labour organisations were central to the success of thecolonial state's policy of “sound” industrial relations in the workplace(private and public). Using primary ...

  19. Industrial air pollution: British progress—a review (United States)

    Nonhebel, G.

    Recent Annual Reports on industrial air pollution issued by the U.K. Health and Safety Executive show that considerable progress has been made. Further "Presumptive Limits of Emission" and "Notes on Best Practicable Means" have been published by H.M. Alkali and Clean Air Inspectorate. The lists given in this journal [9, 709 (1975)] are extended in the Appendices. An abstract is given of BPM for oil refineries. Heavy smoke from blue brick manufacture and from shaft lime kilns has been eliminated by gas firing. Steps have been taken to reduce emissions of vinyl chloride, PCBs, compounds of fluorine and of toxic metals, As, Sb, Cd, Cu, Ni, Pb, Sn, Zn and radioactives. Reduction of low-level emissions is a continuing problem in improving local amenity. Considerable attention has been paid to continuous monitoring of massive emissions and of concentrations of pollutants outside factories, including odours. Arrestment equipment supplied to small firms has given trouble through poor design of components and monitors, inadequate help by suppliers during commissioning, and by lack of training and correct maintenance by management; tight specifications requiring quality engineering should be prepared by purchasers. Lectures to workers, backed by booklets, are assisting in making difficult works better neighbours. The Inspectorate has six sampling teams, mainly for dust, and nine task groups for special programmes. A computer programme for calculation of ground concentrations from multiple sources is assisting inspectors to assess complex situations. It is the author's opinion that research workers on environmental problems should examine these Reports to find more industrial subjects for study.

  20. Symptoms and immunologic markers among vulcanization workers in rubber industries in southern Sweden. (United States)

    Jönsson, Lena S; Broberg, Karin; Axmon, Anna; Jönsson, Bo Ag; Littorin, Margareta


    The aim of this study was to estimate the risk of symptoms and the possible derangement of levels of immunologic markers for contemporary Swedish rubber workers. Furthermore, the relation between exposure and these biomarkers of response was examined using urinary levels of 2-thiothiazolidine-4-carboxylic acid (TTCA), which reflect the exposure. Included in the study were 166 exposed workers and 117 controls. Medical and occupational histories were obtained in structured interviews. Symptoms were recorded, and immunologic markers were analyzed in blood. Urinary levels of TTCA were determined by liquid chromatography tandem mass spectrometry. Compared with the controls, the exposed workers had increased risks of eye symptoms [odds ratio (OR) 3.0], nose bleeds (OR 4.0), burning and dry throat (OR 3.0), hoarseness (OR 2.4), severe dry cough (OR 3.8), nausea (OR 4.3), and headache (OR 2.5). When the exposed workers were divided into three groups according to the TTCA levels, the highest risks were observed among the exposed workers with intermediate TTCA levels. Furthermore, the exposed workers in all of the TTCA subgroups had elevated concentrations of total immunoglobulin G when compared with the controls. Elevated concentrations of leukocytes, neutrophils, and eosinophils were observed in the group with high TTCA levels. This work shows an increased risk of several symptoms and elevated levels of some immunologic markers among exposed workers in Swedish rubber industries. In addition, relationships between urinary levels of TTCA and some biomarkers of response were reported.

  1. An exploration study to find important factors influencing on brand in rubber industry

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    Mehrnaz Moshkelati


    Full Text Available Building a distinguished brand often makes it possible to have sustainable growth in competitive market. It also helps us sell products with higher price; attract reliable customers for long term relationships. This paper presents an empirical investigation to find important factors influencing rubber industry. The proposed study designs a questionnaire in Likert scale consists of 20 questions, distributes it among 300 people and collects 265 filled ones. Cronbach alpha is calculated as 0.756. In addition, Kaiser-Meyer-Olkin Measure of Sampling Adequacy and Approx. Chi-Square are 0.75 and 1292.573, respectively. Based on the results of our survey, we have derived six factors including brand transparency, expected quality, brand promises, brand support and brand sustainability.

  2. Rubber pad forming - Efficient approach for the manufacturing of complex structured sheet metal blanks for food industry (United States)

    Spoelstra, Paul; Djakow, Eugen; Homberg, Werner


    The production of complex organic shapes in sheet metals is gaining more importance in the food industry due to increasing functional and hygienic demands. Hence it is necessary to produce parts with complex geometries promoting cleanability and general sanitation leading to improvement of food safety. In this context, and especially when stainless steel has to be formed into highly complex geometries while maintaining desired surface properties, it is inevitable that alternative manufacturing processes will need to be used which meet these requirements. Rubber pad forming offers high potential when it comes to shaping complex parts with excellent surface quality, with virtually no tool marks and scratches. Especially in cases where only small series are to be produced, rubber pad forming processes offers both technological and economic advantages. Due to the flexible punch, variation in metal thickness can be used with the same forming tool. The investments to set-up Rubber pad forming is low in comparison to conventional sheet metal forming processes. The process facilitates production of shallow sheet metal parts with complex contours and bends. Different bending sequences in a multiple tool set-up can also be conducted. The planned contribution thus describes a brief overview of the rubber pad technology. It shows the prototype rubber pad forming machine which can be used to perform complex part geometries made from stainless steel (1.4301). Based on an analysis of the already existing systems and new machines for rubber pad forming processes, together with their process properties, influencing variables and areas of application, some relevant parts for the food industry are presented.

  3. Occupational exposure to wood dust in the british woodworking industry in 1999/2000. (United States)

    Black, Nigel; Dilworth, Martin; Summers, Nick


    Exposure to inhalable wood dust and compliance with the British Control of Substances Hazardous to Health (COSHH) Regulations 1999 were assessed at a representative cross-section of the British woodworking industry. Median exposures ranged from 1.5 to 2.8 mg/m(3) across the selected industry groups, the lowest being in sawmilling and planing of wood. Overall, 27% of values exceeded the maximum exposure limit (MEL) at that time of 5 mg/m(3). These results showed that the percentage of exposures above the MEL was less than in a survey carried out 10 years earlier. A wide variation of exposures was identified at different machines and tasks. At least 90% at bandsawing and cross-cut sawing were woodworking activities.

  4. A very British phenomenon? Industrial politics and the decline of the Japanese coal mining industry since the 1950s

    Energy Technology Data Exchange (ETDEWEB)

    W.R. Garside


    This paper describes how the Japanese government gradually abandoned its support for coal mining after 1945. Drawing parallels with the British experience during the 1930s, this article shows how coal miners and owners in Japan were able to slow the pace of economic adjustment from the 1950s. The government's initial reluctance to act reflected its willingness to put industrial politics to the fore, preferring to avoid alienating political support and aggravating a vocal unionised sector of the labour force. It eventually accepted and acted upon the need for draconian retrenchment.

  5. Mortality from accidents, disease, suicide and homicide in the British fishing industry from 1900 to 2010. (United States)

    Roberts, Stephen E; Carter, Tim


    To establish the causes of mortality in the British fishing industry from 1900 up to 2010, to investigate long term trends in mortality and to identify causal factors in the mortality patterns and rates. A longitudinal study, based on examinations of official death inquiry files, marine accident investigation files and reports, death registers and annual death returns. Mortality rates from accidents while working at sea remain high in the British fishing industry. Over the twentieth century there has been a progressive fall in the numbers of deaths, much of this relates to changes in fishing methods and in the types of vessels used. However in recent years, and with a fleet of smaller vessels, the mortality rates from accidents have shown little change and a larger proportion of deaths than in the past have arisen from personal injuries and drowning as compared to vessel losses. Disease makes a relatively small contribution to mortality at sea and this has dwindled with the decline in distant water fishing. Suicide and homicide both feature in a small way, but rates cannot readily be compared with those ashore. The pattern of change in vessels, fisheries and fishing techniques over the study period are complex. However, improved injury and drowning prevention is the most important way to reduce deaths, coupled with attention to vessel stability and maintenance. The social, economic and organisational features of the fishing industry mean that securing improvements in these areas is a major challenge.

  6. Aggregate Production Planning, Casestudy in a Medium-sized Industry of the Rubber Production Line in Ecuador. (United States)

    Rosero-Mantilla, César; Sánchez-Sailema, Mayra; Sánchez-Rosero, Carlos; Galleguillos-Pozo, Rosa


    This research aims to improve the productivity in the rubber line of a medium-sized industry by increasing the production capacities through the use of the Aggregate Production Planning model. For this purpose an analysis of the production processes of the line was made and the aggregate plan was defined evaluating two strategies: Exact Production Plan (Zero Inventory) and Constant Workforce Plan (Vary Inventory) by studying the costs of both inventory maintenance and workforce. It was also determined how the installed capacity was used with the standards of the rubber line and measures for decreasing production costs were proposed. It was proven that only 70% of the plant capacity was being used so it could be possible to produce more units and to obtain a bigger market for the products of this line.+

  7. Prevention of exposure to N-nitrosamines in the rubber industry: new vulcanization accelerators based on 'safe' amines. (United States)

    Wacker, C D; Spiegelhalder, B; Börzsönyi, M; Brune, G; Preussmann, R


    Introduction of 'safe' amino components into traditional accelerator molecules could be an effective measure to prevent formation of carcinogenic N-nitroso compounds during rubber production. About 20 new derivatives of the dithiocarbamate and sulfenamide class, based on 'safe' amines, were synthesized and shown to be suitable for industrial application. Some of the corresponding N-nitrosamines were prepared and investigated for mutagenicity in Salmonella typhimurium TA1535. No or weak mutagenic potential was observed in most cases. The nitrosatability of five sulfenamides derived from 'safe' amines was determined and found to be substantially lower than that of a commercial sulfenamide accelerator tested under identical conditions.

  8. Air purification in industrial plants producing automotive rubber components in terms of energy efficiency

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    Grzebielec Andrzej


    Full Text Available In automotive industry plants, which use injection molding machines for rubber processing, tar contaminates air to such an extent that air fails to enter standard heat recovery systems. Accumulated tar clogs ventilation heat recovery exchangers in just a few days. In the plant in which the research was conducted, tar contamination causes blockage of ventilation ducts. The effect of this phenomenon was that every half year channels had to be replaced with new ones, since the economic analysis has shown that cleaning them is not cost-efficient. Air temperature inside such plants is often, even in winter, higher than 30°C. The air, without any means of heat recovery, is discharged outside the buildings. The analyzed plant uses three types of media for production: hot water, cold water at 14°C (produced in a water chiller, and compressed air, generated in a unit with a rated power consumption of 180 kW. The aim of the study is to determine the energy efficiency improvement of this type of manufacturing plant. The main problem to solve is to provide an air purification process so that air can be used in heat recovery devices. The next problem to solve is to recover heat at such a temperature level that it would be possible to produce cold for technological purposes without air purification. Experimental studies have shown that air purification is feasible. By using one microjet head, a total of 75% of tar particles was removed from the air; by using 4 heads, a purification efficiency of 93% was obtained. This method of air purification causes air temperature to decrease from 35°C to 20°C, which significantly reduces the potential for heat recovery. The next step of the research was designing a cassette-plate heat exchanger to exchange heat without air purification. The economic analysis of such a solution revealed that replacing the heat exchanger with a new one even once a year was not cost-efficient. Another issue examined in the context of

  9. Air purification in industrial plants producing automotive rubber components in terms of energy efficiency (United States)

    Grzebielec, Andrzej; Rusowicz, Artur; Szelągowski, Adam


    In automotive industry plants, which use injection molding machines for rubber processing, tar contaminates air to such an extent that air fails to enter standard heat recovery systems. Accumulated tar clogs ventilation heat recovery exchangers in just a few days. In the plant in which the research was conducted, tar contamination causes blockage of ventilation ducts. The effect of this phenomenon was that every half year channels had to be replaced with new ones, since the economic analysis has shown that cleaning them is not cost-efficient. Air temperature inside such plants is often, even in winter, higher than 30°C. The air, without any means of heat recovery, is discharged outside the buildings. The analyzed plant uses three types of media for production: hot water, cold water at 14°C (produced in a water chiller), and compressed air, generated in a unit with a rated power consumption of 180 kW. The aim of the study is to determine the energy efficiency improvement of this type of manufacturing plant. The main problem to solve is to provide an air purification process so that air can be used in heat recovery devices. The next problem to solve is to recover heat at such a temperature level that it would be possible to produce cold for technological purposes without air purification. Experimental studies have shown that air purification is feasible. By using one microjet head, a total of 75% of tar particles was removed from the air; by using 4 heads, a purification efficiency of 93% was obtained. This method of air purification causes air temperature to decrease from 35°C to 20°C, which significantly reduces the potential for heat recovery. The next step of the research was designing a cassette-plate heat exchanger to exchange heat without air purification. The economic analysis of such a solution revealed that replacing the heat exchanger with a new one even once a year was not cost-efficient. Another issue examined in the context of energy efficiency was

  10. British Columbia hydrogen and fuel cell strategy : an industry vision for our hydrogen future

    Energy Technology Data Exchange (ETDEWEB)



    British Columbia's strategy for global leadership in hydrogen fuel cell technology was outlined. It was suggested that hydrogen and fuel cells will power a significant portion of the province by 2020, and will be used in homes, businesses, industry and transportation. The following 3 streams of activity were identified as leading to the achievement of this vision: (1) a hydrogen highway of technology demonstrations in vehicles, refuelling facilities and stationary power systems in time for and building on the 2010 Winter Olympic and Paralympic Games, (2) the development of a globally leading sustainable energy technology cluster that delivers products and services as well as securing high-value jobs, and (3) the renewal of the province's resource heartlands to supply the fuel and knowledge base for hydrogen-based communities and industries, and clean hydrogen production and distribution. It was suggested that in order to achieve the aforementioned goals, the government should promote the hydrogen highway and obtain $135 million in funding from various sources. It was recommended that the BC government and members of industry should also work with the federal government and other provinces to make Canada an early adopter market. Creative markets for BC products and services both in Canada and abroad will be accomplished by global partnerships, collaboration with Alberta and the United States. It was suggested that in order to deploy clean energy technologies, BC must integrate their strategy into the province's long-term sustainable energy plan. It was concluded that the hydrogen and fuel cell cluster has already contributed to the economy through jobs, private sector investment and federal and provincial tax revenues. The technology cluster's revenues have been projected at $3 billion with a workforce of 10,000 people by 2010. The hydrogen economy will reduce provincial air emissions, improve public health, and support sustainable tourism

  11. Cancer incidence in cohorts of workers in the rubber manufacturing industry first employed since 1975 in the UK and Sweden. (United States)

    Boniol, M; Koechlin, A; Sorahan, T; Jakobsson, K; Boyle, P


    Increased cancer risks have been reported among workers in the rubber manufacturing industry employed before the 1960s, but it is unclear for workers hired subsequently. The present study focused on cancer incidence among rubber workers first employed after 1975 in Sweden and the UK. Two cohorts of rubber workers employed for at least 1 year were analysed. Standardised incidence ratios (SIRs), based on country-specific and period-specific incidence rates, were analysed for all cancers combined (except non-melanoma skin), bladder, lung, stomach cancer, leukaemia, non-Hodgkin's lymphoma and multiple myeloma. Exploratory analyses were conducted for other cancers with a minimum of 10 cases in both genders combined. 16 026 individuals (12 441 men; 3585 women) contributed to 397 975 person-years of observation, with 846 cancers observed overall (437 in the UK, 409 in Sweden). No statistically significant increased risk was observed for any site of cancer. A reduced risk was evident for all cancers combined (SIR=0.83, 95% CI (0.74 to 0.92)), lung cancer (SIR=0.74, 95% CI (0.59 to 0.93)), non-Hodgkin's lymphoma (SIR=0.67, 95% CI (0.45 to 1.00)) and prostate cancer (SIR=0.77, 95% CI (0.64 to 0.92)). For stomach cancer and multiple myeloma, SIRs were 0.93 (95% CI (0.61 to 1.43)) and 0.92 (95% CI 0.44 to 1.91), respectively. No increased risk of bladder cancer was observed (SIR=0.88, 95% CI (0.61 to 1.28)). No significantly increased risk of cancer incidence was observed in the combined cohort of rubber workers first employed since 1975. Continued surveillance of the present cohorts is required to confirm absence of long-term risk and confirmatory findings from other cohorts would be important. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to

  12. Influence of glutathione-related genes on symptoms and immunologic markers among vulcanization workers in the southern Sweden rubber industries. (United States)

    Jönsson, Lena S; Jönsson, Bo A G; Axmon, Anna; Littorin, Margareta; Broberg, Karin


    The aim was to elucidate the role of genetic variants on symptoms of the eyes and airways, headache and nausea, as well as on immunologic markers, among vulcanization workers in the contemporary Swedish rubber industry. Polymorphisms in genes, which are involved in the defense against reactive oxygen species and metabolism of toxic substances present in the vulcanization fumes, were analyzed. One hundred and forty-five exposed and 117 unexposed workers were included in the study. Medical and occupational histories were obtained in structured interviews. Symptoms were recorded and immunologic markers analyzed in blood. Polymorphisms in glutathione-related genes (glutamate cysteine ligase catalytic subunit (GCLC)-129, glutamate cysteine ligase modifier subunit (GCLM)-588, glutathione S-transferase alpha 1 (GSTA1)-52, GSTM1*O, GSTP1-105, GSTP1-114, and GSTT1*O) were analyzed by Taqman-based allelic discrimination and ordinary PCR. A protective effect of GSTA1-52 (G/A + A/A) genotype on symptoms and immunologic cells, in particular among exposed workers, was suggested. Exposed workers with GSTT1*O had increased risk of nosebleed compared to exposed workers with GSTT1*1. Exposed workers with GSTP1-105 (ile/val + val/val) had decreased levels of total immunoglobulin E (IgE) compared to exposed workers with GSTP1-105 ile/ile. GCLC-129 variant genotype demonstrated increased levels of immunologic cells among exposed workers, although statistical significance was not reached. Our data indicate that hereditary factors influence the susceptibility to symptoms and the immunologic response of workers in the rubber industry.

  13. Who Wants to be a Millionaire? Gendered Entrepreneurship and British South Asian Women in the Culture Industries


    Basu, Dipannita; Werbner, Pnina


    The 200 Richest Asians Magazines 2000, 2002, 2003 construct the success of British South Asian multi-millionaires in images that foreground their masculine traits and characteristics. And yet, this paper argues, such individual success stories are merely the tip of an “entrepreneurial iceberg”. They mask the existence of clusters of immigrant enterprises concentrated in particular economic sectors and industries. These may be headed by women as well as men. While South Asian men in Britain in...


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    Pruethsan Sutthichaimethee


    Full Text Available This study aims to analyze the forecasting of CO2 emission from the energy consumption in the Rubber, Chemical and Petroleum Industries sectors in Thailand. The scope of research employed the input-output table of Thailand from the year 2000 to 2015. It was used to create the model of CO2 emission, population, GDP growth and predict ten years and thirty years in advance. The model used was the VARIMAX Model which was divided into two models. The results show that from the first model by using which predicted the duration of ten years (2016-2025 by using VARIMAX Model (2,1,2, On average, Thailand has 17.65% higher quantity of CO2 emission than the energy consumption sector (in 2025. The second model predicted the duration of 30 years (2016-2045 by using VARIMAX Model (2,1,3 shows that Thailand has average 39.68% higher quantity of CO2 emission than the energy consumption sector (in 2025. From the analyses, it shows that Thailand has continuously higher quantity of CO2 emission from the energy consumption. This negatively affects the environmental system and economical system of the country incessantly. This effect can lead to unsustainable development.

  15. Levels of 2-thiothiazolidine-4-carboxylic acid (TTCA) and effect modification of polymorphisms of glutathione-related genes in vulcanization workers in the southern Sweden rubber industries. (United States)

    Jönsson, Lena S; Broberg, Karin; Bergendorf, Ulf; Axmon, Anna; Littorin, Margareta; Jönsson, Bo A G


    Workers in the rubber industry are exposed to a complex mixture of hazardous substances and have increased risk of developing several diseases. However, there is no up to date survey examining the exposure in the Swedish rubber industry. One of the toxic compounds in the industry is carbon disulfide (CS(2)), which is biotransformed to 2-thiothiazolidine-4-carboxylic acid (TTCA). TTCA is used as a biomarker of CS(2) exposure, but there seem to exist inter- and intraindividual variability; which could partly be due to genetic variation. The aim of the study was to determine TTCA levels and the modifying effects of glutathione-related genes in a group of Swedish rubber workers. Urine was collected from both exposed workers and controls during the last 4 h of the work shift. The level of TTCA in urine was analyzed by liquid chromatograpy tandem mass spectrometry. Genotyping of the single nucleotide polymorphisms GCLC-129, GCLM-588, GSTA1-52, GSTP1-105 and GSTP1-114 and deletions of GSTM1 and GSTT1 were performed with real-time PCR or ordinary PCR and subsequent agarose electrophoresis. The highest levels of TTCA were found among workers curing with salt bath, hot air, microwaves or fluid-bed, and lower levels were found among workers curing with injection and compression molding. Furthermore, with respect to GSTM1 and GSTT1 there were statistically significant differences in TTCA-levels between genotypes among exposed workers but not among controls. The other five polymorphisms had no impact on the TTCA levels. The present study demonstrates relatively high levels of TTCA in urine from Swedish rubber workers. Polymorphisms in GSTM1 and GSTT1 modify the levels.

  16. New industrial heat pump applications to a synthetic rubber plant. Final report, Phase IIA

    Energy Technology Data Exchange (ETDEWEB)



    This report summarizes the results of the Phase IIA of the DOE sponsored study titled, Advanced Industrial Heat Pump Application and Evaluation. The scope of this phase of the study was to finalize the process design of the heat pump scheme, develop a process and instrumentation diagram, and a detailed cost estimate for the project. This information is essential for the site management to evaluate the economic viability and operability of the proposed heat pump design, prior to the next phase of installation and testing.

  17. Radiation vulcanization of rubbers

    Energy Technology Data Exchange (ETDEWEB)

    Makuuchi, Keizo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment


    An abstract of the radiation process of polymer materials and the polymer reaction by radiation is explained. Main radiation is 250 keV to 10 MeV of electron rays in the industry. Radiation cross-linked rubber has less the tensile strength than that by sulfur and organic peroxide crosslinking. The main origins of low tensile strength are caused by cut of backbone chain and ozone depend on radiation. Acceleration of crosslinking and short time of radiation are necessary to improve these defects. To accelerate crosslinking, we used crosslinking accelerators, for example, three poly-functional monomers (PFM). The maximum tensile strength of styrene-butadiene rubber (SBR) not added crosslinking accelerators showed 3 MPa at 110 kGy, but SBR added A-TMMT (tetramethylolmethane tetraacrylate) showed 5.5 MPa at 110 kGy. Radiation crosslinking of many kinds of rubber: isoprene (IR), SBR, CR, nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), butyl rubber (IIR), chlorinated butyl rubber (CIIR), EPM and TPE are explained. (S.Y.)

  18. Exposure to rubber process dust and fume since 1970s in the United Kingdom; influence of origin of measurement data. (United States)

    Agostini, Michela; de Vocht, Frank; van Tongeren, Martie; Cherrie, John W; Galea, Karen S; Kromhout, Hans


    The objective of this study was to compare measured concentrations of rubber process dust and rubber fume originating from different sources in the British rubber manufacturing industry. Almost 8000 exposure measurements were obtained from industry-based survey results collected by the British Rubber Manufacturers' Association (BRMA), and covering the years 1977 to 2002, and from a series of small surveys contained in the Health and Safety Executive's (HSE) National Exposure Database (HSE-NEDB) from 1980 to 2002. The analysis investigated temporal trends in the exposure concentrations and the underlying main factors responsible for these changes. Analyses were carried out using hierarchical linear mixed effects models. Average personal exposures to rubber process dust and rubber fumes were respectively a factor 2 and 4 higher for the HSE-NEDB data when compared to data originating from the industry (BRMA data). Personal exposure to rubber process dust decreased on average by 4.1% (95% CI 4.7-3.6) annually for the BRMA data and slightly less at 2.3% (95% CI 5.2-0.7%) per annum for the HSE-NEDB data. Personal exposure to rubber fume also showed a downward temporal trend of 2.9% (95% CI 3.6-2.3%) and 4.8% (95% CI 7.4-2.1%) annually for the BRMA and HSE-NEDB data, respectively. These trends differed considerably between departments. No major changes in the estimated temporal trends in exposure concentrations were observed after including the presence of local exhaust ventilation in the models for any department in the BRMA and HSE-NEDB datasets. Lack of information on the quality and status of the local exhaust ventilation is the most likely explanation for this. In conclusion, even though there were relatively similar downward time trends in both rubber process dust and fume concentrations in both datasets, the source of exposure data was an important determinant of average exposure concentrations present in the British rubber manufacturing industry. Lack of detailed

  19. Emanuel Edward Klein, a diligent and industrious plodder or the father of British microbiology

    Directory of Open Access Journals (Sweden)

    Bruno Atalić


    Full Text Available Emanuel Edward Klein (Osijek, 1844 - Hove, 1925 was a Britishmicrobiologist of Croatian origin. He completed his medical studies in Vienna in 1869. In 1869 he was sent to England to determine terms for the translation of Samuel Stricker’s manual Handbuch von den Geweben des Menchen und der Tiere. During his visit he made a good impression on John Burdon Sanderson and John Simon, which was the main reason why he was invited to London in 1871 to conduct investigations under their guidance. In 1873 Klein began his collaboration with the Saint Bartholomew‘s Hospital, where he was appointed as a Joint Professor of General Anatomy and Physiology. His researches were in the fields of anatomy, histology, pathology, embryology, physiology, and especially microbiology. He did a great deal to its development in Britain. He has written about 260 scientific papers on a broad range of different topics. Despite all the aforementioned facts, his work was never properly studied, and he is almost unknown outside academic circles. For that reason, attitudes towards him still range between the extremes of calling him the father of British microbiology on one side, and attributing him as a diligent and idustrious plodder on the other. In this paper we will try to prove the first attitude. We will put his researches in a general context. Finally we will highlight his original achievements in the isolation of new microbes.


    Directory of Open Access Journals (Sweden)

    Cornelia LUCA


    Full Text Available The leather confections industry uses the silicone rubber moulds for the symbols,notices and models stamping on the footwear or morocco goods parts. The paper presents somecontributions in this kind of devices manufacturing technology

  1. Through tobacco industry eyes: civil society and the FCTC process from Philip Morris and British American Tobacco's perspectives. (United States)

    Gonzalez, Mariaelena; Green, Lawrence W; Glantz, Stanton A


    To analyse the models Philip Morris (PM) and British American Tobacco (BAT) used internally to understand tobacco control non-governmental organizations (NGOs) and their relationship to the global tobacco control policy-making process that resulted in the Framework Convention for Tobacco Control (FCTC). Analysis of internal tobacco industry documents in the Legacy Tobacco Document Library. PM contracted with Mongoven, Biscoe, and Duchin, Inc. (MBD, a consulting firm specialising in NGO surveillance) as advisors. MBD argued that because NGOs are increasingly linked to epistemic communities, NGOs could insert themselves into the global policy-making process and influence the discourse surrounding the treaty-making process. MBD advised PM to insert itself into the policy-making process, mimicking NGO behaviour. BAT's Consumer and Regulatory Affairs (CORA) department argued that global regulation emerged from the perception (by NGOs and governments) that the industry could not regulate itself, leading to BAT advocating social alignment and self-regulation to minimise the impact of the FCTC. Most efforts to block or redirect the FCTC failed. PM and BAT articulated a global policy-making environment in which NGOs are key, non-state stakeholders, and as a result, internationalised some of their previous national-level strategies. After both companies failed to prevent the FCTC, their strategies began to align. Multinational corporations have continued to successfully employ some of the strategies outlined in this paper at the local and national level while being formally excluded from ongoing FCTC negotiations at the global level.

  2. Allergic reactions to natural rubber. (United States)

    Slater, J E


    Immediate hypersensitivity reactions to natural rubber pose a significant risk to patients with spina bifida and urogenital abnormalities, health care workers, and rubber industry workers. Other patients, outside of these high risk groups, have experienced severe allergic reactions to natural rubber as well. Awareness of this life-threatening condition by health care providers is essential if reactions are to be prevented. History alone is inadequate to identify all patients at risk, and reliable testing materials are not yet approved or widely available. Nonrubber medical devices are readily available for most uses; however, the only rubber-free condoms currently on the market do not prevent the transmission of sexually transmitted disease. The identification and detection of rubber antigens, along with mandated labeling for rubber antigen content, will contribute to the care of this growing population of patients. Efforts by the rubber industry to decrease the antigen content of natural rubber products will decrease the risk of reaction among sensitized patients and will, very likely, decrease the rate of sensitization in the future.

  3. Patents for invention: setting the stage for the British industrial revolution?

    Directory of Open Access Journals (Sweden)



    Full Text Available La importancia de las patentes para el desarrollo económico en general y para la industrialización inglesa en particular sigue siendo una cuestión sin resolver a pesar de la intensa investigación histórica que ha tenido lugar en los últimos veinticinco años. Este artículo reexamina este debate a la luz de estas investigaciones y de la historia revisionista de la revolución industrial inglesa. El artículo se centra en la naturaleza y en el funcionamiento del sistema de patentes inglés durante el siglo XVIII y parte del siglo XIX, concretamente hasta la reforma de 1852. En primer lugar se reinterpreta la tendencia al alza en el número de patentes desde 1762 y coincidiendo con los supuestos años clásicos de la revolución industrial. En segundo lugar, se investiga que parte de la actividad inventiva tuvo lugar fuera del sistema de patentes, esto es, no fue capturado en las estadísticas. En tercer lugar, se sugiere que debemos pensar en el sistema de patentes como una tecnología que, como cualquier otra, fue conformada por las circunstancias en que tuvo lugar su invención y desarrollo. Este sistema fue el producto de un periodo en el que la propiedad se redefinió como un derecho privado exclusivo. A menos que reconozcamos que una patente crea, ante todo, un derecho de propiedad privada estaremos equivocando el punto de vista. Las patentes tenían que ver tanto con la inversión como con la invención. En conclusión, este artículo revierte el famoso argumento de Douglass North, y ofrece, en su lugar, el argumento de que fue la revolución industrial la que creó el marco para el surgimiento del sistema de patentes.

  4. Materials for the General Aviation Industry: Effect of Environment on Mechanical Properties of Glass Fabric/Rubber Toughened Vinyl Ester Laminates (United States)

    McBride, Timothy M.


    A screening evaluation is being conducted to determine the performance of several glass fabric/vinyl ester composite material systems for use in primary General Aviation aircraft structures. In efforts to revitalize the General Aviation industry, the Integrated Design and Manufacturing Work Package for General Aviation Airframe and Propeller Structures is seeking to develop novel composite materials and low-cost manufacturing methods for lighter, safer and more affordable small aircraft. In support of this Work Package, this study is generating material properties for several glass fabric/rubber toughened vinyl ester composite systems and investigates the effect of environment on property retention. All laminates are made using the Seemann Composites Resin Infusion Molding Process (SCRIMP), a potential manufacturing method for the General Aviation industry.

  5. Hydrogenated nitrile rubber for improved durability of automotive rubber parts

    Energy Technology Data Exchange (ETDEWEB)

    Mirza, J.; Leibbrandt, F.; Thoermer, J.


    Rubber articles with improved heat resistance and better performance characteristics are becoming of increasing importance for the automotive industry. A new type of elastomer has therefore been developed based on saturated hydrocarbon backbone - for improved heat resistance - with nitrile side groups providing good resistance to swelling. Some of the typical characteristics of hydrogenated nitrile rubber (HNBR) vulcanizates such as good physical properties pattern at elevated low temperatures dynamic properties, ozone resistance and swelling in automotive fluids are discussed. Potential applications are suggested to improve the performance of various rubber parts used in automotive applications such as high performance seals.

  6. [To-day exposure to occupational carcinogens and their effects. The experience of the rubber industry, iron metallurgy, asphalt work and aviculture]. (United States)

    Barbieri, Pietro Gino


    While the progressive improvement of hygiene situations in the workplaces has taken to a reduction of chemical carcinogens exposure, in recent years in Italy the number of compensated occupational cancer resulting from carcinogens exposures of distant decades, has been increasing. Nevertheless, several experiences suggest that the proportion of occupational cancers unrecognised and not notified, as required by law, still remains important. This contribution concerns some experiences, performed between 2004-2008 by the Local Occupational Health Service (SPSAL) located in a highly industrialised province, on the working sector of rubber, iron and steel industry, the asphalt working and the poultry stock-breeders. This work concerns the following issues: - the evaluation of carcinogens exposure; - technical preventive measures and personal protection; - the level of workers' information and formation and the registration of exposed workers; - the characterization of work-related cancer. The results of the 5 years of activity allow us to underline that, in the most of 49 plants involved in the study, the carcinogens exposure evaluation and the prevention and protection measures were lacking. Information of workers was largely deficient and the registration of exposed workers was absent. A major attention to detect and to evaluate the work-related cancer has allowed us to recognize 50 new cases in the iron-steel industries and 21 new cases in a rubber industry. Although this experience concerns only few occupational fields, it provides the basis to call for a greater commitment of SPSAL addressed to companies and general practitioners to both, the promotion and surveillance of the correct procedures of carcinogens exposure evaluation and his prevention, and the active detection of occupational cancer, still missing.

  7. Regulamentação pública e conduta das firmas no sistema agroindustrial da borracha natural entre 1997 e 2000 Regulation and behavior of firms in Brazil's natural rubber agro-industrial system between 1997-2000

    Directory of Open Access Journals (Sweden)

    Augusto Hauber Gamero


    Full Text Available A necessidade de regulamentação no sistema agroindustrial (SAG da borracha natural no Brasil é evidente. Desde a metade do século, quando o país passou a importar esse produto, vários esforços governamentais vêm sendo definidos, objetivando o desenvolvimento sustentável do setor da produção agrícola nacional de borracha. No ano de 1997, criou-se uma política de subvenção direta à produção. Dada a estrutura desse SAG, associada à conjuntura do mercado internacional e a uma regulamentação falha do governo federal, começaram a surgir indícios de abuso de poder de mercado pela indústria pneumática instalada no país, principal consumidora do produto. Utilizando o arcabouço teórico da organização industrial, neste artigo se procurou levantar evidências nesse sentido.The need for regulation of Brazil’s natural rubber agro-industrial system (SAG is evident. Since the middle of the 20th century, when the country began importing rubber, many governmental efforts have been made to promote the sustainable development of Brazil’s natural rubber productive sector. In 1997, the Brazilian government created a direct subvention policy to assist rubber producers. Given the structure of Brazil’s SAG, the international rubber market, and imperfect regulation by the Federal Government, it would not be unexpected to find signs that Brazil’s largest natural rubber consumer, the domestic tire industry, has begun to abusively exercise its market power. Using the theoretical structure of Industrial Organization, this paper tries to show evidences of this abuse.

  8. Statistical Analysis of Reducing Biochemical Oxygen Demand (BOD) on Industrial Rubber Wastewater using Dielectric Barrier Discharge Plasma (United States)

    Syakur, Abdul; Zaman, Badrus; Yunita Nurmaliakasih, Dias


    Dielectric Barrier Discharge plasma (DBD) is one of type non-thermal plasma (non-equilibrium plasma) or can be referred to as cold plasma. In this research, DBD plasma be utilized to reduce organic compounds like Biochemichal oxygen demand in the wastewater rubber processing. In the environment field DBD plasma has been used as a treatment for reducing air pollutants such as gas COx, NOx and HC. In addition DBD plasma have been developed to processed wastewater as an alternative technology in wastewater treatment. DBD plasma appears when the electrode is given a high voltage so that, it will form electric field in the area of the electrodes which allows the ionization and the presence of high-energy electrons in the area. The presence of these electrons will ionize molecules of H2O into active species such as OH•, H• and H2O2. The active species that can oxidize into CO2 and H2O so, BOD that can be degraded. In this research for wastewater treatment used high voltage are 10kV, 11kV, 12kV and 13kV and variations of processing time for 5, 10, 15, 20, and 25 (minutes). By increasing the voltage and extend the contact time then the speed variation of electrons to ionize the greater and more active species to be formed to degrade the pollutants to the maximum. This research used quantitative analysis with statistical analysis using SPSS software.

  9. Rubber compounding and processing

    CSIR Research Space (South Africa)

    John, MJ


    Full Text Available This chapter presents an overview on the compounding and processing techniques of natural rubber compounds. The introductory portion deals with different types of rubbers and principles of rubber compounding. The primary and secondary fillers used...

  10. Science in the service of colonial agro-industrialism: the case of cinchona cultivation in the Dutch and British East Indies, 1852-1900. (United States)

    Roersch van der Hoogte, Arjo; Pieters, Toine


    The isolation of quinine from cinchona bark in 1820 opened new possibilities for the mass-production and consumption of a popular medicine that was suitable for the treatment of intermittent (malarial) fevers and other diseases. As the 19th century European empires expanded in Africa and Asia, control of tropical diseases such as malaria was seen as crucial. Consequently, quinine and cinchona became a pivotal tool of British, French, German and Dutch empire-builders. This comparative study shows how the interplay between science, industry and government resulted in different historical trajectories for cinchona and quinine in the Dutch and British Empires during the second half of the 19th century. We argue that in the Dutch case the vectors of assemblage that provided the institutional and physical framework for communication, exchange and control represent an early example of commodification of colonial science. Furthermore, both historical trajectories show how the employment of the laboratory as a new device materialised within the colonial context of agricultural and industrial production of raw materials (cinchona bark), semi-finished product (quinine sulphate) and plant-based medicines like quinine. Hence, illustrating the 19th century transition from 'colonial botany' and 'green imperialism' to what we conceptualise as 'colonial agro-industrialism'. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Pengaruh Temperatur Vulkanisasi Terhadap Kekuatan Tarik (Tensile Strength) Pada Packing Pintu Rebusan PT. Industri Karet Nusantara Medan


    Ayutami, Rizki


    In this paper will discuss how is the influence of temperature vulcanization which in used at Rubber Articles Factory in PT. Rubbin Industry Nusantara Medan. The start with selection raw materials natural rubber and synthetic rubber in used until became rubber articles. The variety rubber which in used to produce rubber articles is rubber smoke sheet, there for variety synthetic rubber which used is SBR (Styrine Butadine Rubber). At the first process, main material rubber and chemical is mixe...

  12. On the Elasticity of Effort for Piece Rates: Evidence from the British Columbia Tree-Planting Industry


    Paarsch, Harry J.; Shearer, Bruce S.


    If policy prescriptions for compensation systems are to be useful, then they must be based on the empirical analysis of incentive effects; i.e., the elasticity of worker effort with respect to changes in the compensation system. We measure the elasticity of worker effort with respect to changes in the piece rate using panel data collected from the payroll records of a British Columbia tree-planting firm. Our data contain information on daily worker productivity and the piece rate received ove...

  13. The rubber tree genome reveals new insights into rubber production and species adaptation. (United States)

    Tang, Chaorong; Yang, Meng; Fang, Yongjun; Luo, Yingfeng; Gao, Shenghan; Xiao, Xiaohu; An, Zewei; Zhou, Binhui; Zhang, Bing; Tan, Xinyu; Yeang, Hoong-Yeet; Qin, Yunxia; Yang, Jianghua; Lin, Qiang; Mei, Hailiang; Montoro, Pascal; Long, Xiangyu; Qi, Jiyan; Hua, Yuwei; He, Zilong; Sun, Min; Li, Wenjie; Zeng, Xia; Cheng, Han; Liu, Ying; Yang, Jin; Tian, Weimin; Zhuang, Nansheng; Zeng, Rizhong; Li, Dejun; He, Peng; Li, Zhe; Zou, Zhi; Li, Shuangli; Li, Chenji; Wang, Jixiang; Wei, Dong; Lai, Chao-Qiang; Luo, Wei; Yu, Jun; Hu, Songnian; Huang, Huasun


    The Para rubber tree (Hevea brasiliensis) is an economically important tropical tree species that produces natural rubber, an essential industrial raw material. Here we present a high-quality genome assembly of this species (1.37 Gb, scaffold N50 = 1.28 Mb) that covers 93.8% of the genome (1.47 Gb) and harbours 43,792 predicted protein-coding genes. A striking expansion of the REF/SRPP (rubber elongation factor/small rubber particle protein) gene family and its divergence into several laticifer-specific isoforms seem crucial for rubber biosynthesis. The REF/SRPP family has isoforms with sizes similar to or larger than SRPP1 (204 amino acids) in 17 other plants examined, but no isoforms with similar sizes to REF1 (138 amino acids), the predominant molecular variant. A pivotal point in Hevea evolution was the emergence of REF1, which is located on the surface of large rubber particles that account for 93% of rubber in the latex (despite constituting only 6% of total rubber particles, large and small). The stringent control of ethylene synthesis under active ethylene signalling and response in laticifers resolves a longstanding mystery of ethylene stimulation in rubber production. Our study, which includes the re-sequencing of five other Hevea cultivars and extensive RNA-seq data, provides a valuable resource for functional genomics and tools for breeding elite Hevea cultivars.

  14. "A WAR OF MACHINERY”: the British Machine Tool Industry and Arming the Western Front, 1914-1916

    Directory of Open Access Journals (Sweden)

    Roger Lloyd-Jones


    Full Text Available According to David Lloyd George, Britain’s first Minister of Munitions, World War L “the Great War” was a “war of machinery,” and required unprecedented supplies of ammunition and the machine tools necessary to make them. In the early phase of the conflict, when the importance of machine tools was not fully recognized, a shortage of ammunition on the western front precipitated a military and political crisis, and led to the formation of the Ministry of Munitions. A trade-off between quantity and quality of ammunition shell (the machined outer metal casing was a product of the Ministry directive to increase output as both makers and users of machine tools came under intense pressure to reach their goals. British engineering achieved huge increases in ammunition output in preparation for the Somme offensive, but the complexities of the supply chain meant that makers and users of machine tools put them to use to make ammunition of a type and quality that was to prove defective.

  15. How much did cold shock and swimming failure contribute to drowning deaths in the fishing industry in British Columbia 1976-2002? (United States)

    Brooks, C J; Howard, K A; Neifer, S K


    The Workers' Compensation Board of British Columbia requested a retrospective analysis of all fishermen's deaths from immersion in water in British Columbia. To identify the underlying cause of drowning and make recommendations to improve safety in the fishing industry. Eighty-nine inshore and offshore fishing accidents were analysed. Where possible, deaths were classified into the four stages of cold-water immersion: cold shock, swimming failure, hypothermia and post-rescue collapse. Other factors that led up to the drowning were also identified. One hundred and thirty fishermen died from immersion between 1976 and 2002. One hundred and twenty-eight drownings were certified by the coroner as drowning or drowning/hypothermia and two were certified as cardiac event after immersion. The underlying causes of drownings were reclassified as: cold shock (5.4%), swimming failure (5.4%), hypothermia (5.4%), post-rescue collapse (0.8%), cardiac event (0.8%) and drowning/other (10%). In the remaining 72.2% of deaths, there was insufficient information to determine an underlying cause. All deaths occurred in water below 17.5 degrees C but 95% were in water less than 15 degrees C. Immersion in water below 15 degrees C is dangerous and this should be emphasized on marine survival courses. Accident investigators, coroners and pathologists need a common checklist to record vital data. A recommended format is included as Supplementary data available at Occupational Medicine Online. Fishermen should be educated about the dangers of sudden, unexpected immersion in cold water. Consideration should be given to making marine survival courses mandatory for fishermen.

  16. Cryogenic Deflashing for Rubber Products

    Directory of Open Access Journals (Sweden)

    Abhilash M.


    Full Text Available Deflashing is the process of removal of excess flashes from the rubber products. Initially deflashing was a manual operation where dozen of workers, seated at small work stations would take each part and trim the excess rubber off with scissors, knives or by grinding. Still the same method is employed in most of the rubber industry. The drawbacks of this method are demand inconsistent and repeatable quality. Work done by hand is often inconsistent. There are commercially available cryogenic deflashing machine but they are too expensive hence cost effectiveness is also a prime factor. The objective of this paper is to develop a technique, to identify the media through which the flashes can be removed easily and effectively. Based on the test results obtained from testing of five different types of media, ABCUT Steel media gave best results. The testing of the ABCUT Steel media on rubber samples like O-rings, grommet tail door, bottom bush etc. shows good results.

  17. History of Rubber and Its Use (United States)

    Müller, Ingo; Strehlow, Peter

    Despite its spectacular properties rubber was not much good for anything before the latter part of the 19th century. To be sure the Aztecs had used it to make balls for their ceremonial ball games - or so we are told. But those games died along with the Aztec culture in the 16th century and there is no record of other useful applications until the late 18th century. But then, after that, rubber took off in a small way. After the American inventor Samuel Peal had obtained a patent in 1791 for the production of rubber-coated watertight textiles, the Scottish chemist Charles Macintosh (1766-1843) used such textiles for making rain-coats, and Thomas Hancock (1786-1865) produced rubber boots. At that time it was not really appropriate to speak of a rubber industry. What little material the evil-smelling workshops in New York and London needed, could be satisfied with the import of 30 tons of Caoutchouc1 annually - extracted from the sap of the tree Hevea brasiliensis - and most of that went for making erasers. Indeed, it had been reported by the English minister and scientist Joseph Priestley (1733-1804) that pieces of rubber are well-suited to rub out (sic!) pencil marks. Even today there is nothing better for the purpose and rubber became the English word for Caoutchouc.

  18. Cream concentrated latex for foam rubber products (United States)

    Suksup, R.; Imkaew, C.; Smitthipong, W.


    Fresh natural latex (around 40% rubber and 60% water) can be transformed to concentrated natural latex (around 60% rubber and 40% water) in order to realise economical transportation and easier latex product’s preparation. The concentrated natural latex is an extremely valuable material. It can be applied for many types of products, for example, foam rubber as pillow and mattress, elastic band, etc. Industrially, the concentrated natural latex can be prepared by centrifugation which requires an enormous expensive machine. From the eco-friendly products point of view, most of rubber entrepreneurs in the world try to develop a green rubber product. So, the main objective of this study is to prepare the cream concentrated latex without any sophisticated machine. Thus, we work on a simple, cheap and green method that does not use any expensive machine but uses water-based chemical as sodium alginate to prepare the cream concentrated latex. The optimal amount of sodium alginate in the latex was studied. The main characteristics of the cream concentrated latex were tested by various technics, such as alkalinity, total solid content (TSC), dry rubber content (DRC), etc. We found that there are no significant differences of results between fresh natural latex and cream concentrated latex, except for the TSC and DRC. The TSC and DRC of cream latex are higher than those of fresh natural latex. Finally, we propose a model of natural rubber particle and sodium alginate to form the cream concentrated latex.

  19. Flashover Characteristics of Silicone Rubber Sheets under Various Environmental Conditions


    Arshad; Azam Nekahi; Scott G. McMeekin; Masoud Farzaneh


    Silicone rubber insulators are replacing the conventional ceramic and porcelain insulators rapidly in power transmission and distribution industry. Very limited field knowledge is available about the performance of silicone rubber insulators in polluted and contaminated environments and therefore need further investigation. A comprehensive analysis of silicone rubber sheets (intended for coating outdoor insulators) was carried out in this paper based on experimental results. The main performa...

  20. British passports

    CERN Multimedia

    IT Department


    Please note that from 01/01/2009, the passport section of the British Consulate will move from Geneva to Paris. This change is part of a global initiative to rationalize passport services and reduce administrative costs while ensuring that the quality of the service remains high. The aim is to issue new passports within 10 working days of receiving applications (excluding transit time). From 1st January 2009 passport applications should be sent by courier or registered post directly to: British Consulate General BP111-08 75363 Paris CEDEX 08 France For further information please refer to:

  1. Generating social network data using partially described networks: an example informing avian influenza control in the British poultry industry

    Directory of Open Access Journals (Sweden)

    Nickbakhsh Sema


    Full Text Available Abstract Background Targeted sampling can capture the characteristics of more vulnerable sectors of a population, but may bias the picture of population level disease risk. When sampling network data, an incomplete description of the population may arise leading to biased estimates of between-host connectivity. Avian influenza (AI control planning in Great Britain (GB provides one example where network data for the poultry industry (the Poultry Network Database or PND, targeted large premises and is consequently demographically biased. Exposing the effect of such biases on the geographical distribution of network properties could help target future poultry network data collection exercises. These data will be important for informing the control of potential future disease outbreaks. Results The PND was used to compute between-farm association frequencies, assuming that farms sharing the same slaughterhouse or catching company, or through integration, are potentially epidemiologically linked. The fitted statistical models were extrapolated to the Great Britain Poultry Register (GBPR; this dataset is more representative of the poultry industry but lacks network information. This comparison showed how systematic biases in the demographic characterisation of a network, resulting from targeted sampling procedures, can bias the derived picture of between-host connectivity within the network. Conclusions With particular reference to the predictive modeling of AI in GB, we find significantly different connectivity patterns across GB when network estimates incorporate the more demographically representative information provided by the GBPR; this has not been accounted for by previous epidemiological analyses. We recommend ranking geographical regions, based on relative confidence in extrapolated estimates, for prioritising further data collection. Evaluating whether and how the between-farm association frequencies impact on the risk of between

  2. Generating social network data using partially described networks: an example informing avian influenza control in the British poultry industry. (United States)

    Nickbakhsh, Sema; Matthews, Louise; Bessell, Paul R; Reid, Stuart W J; Kao, Rowland R


    Targeted sampling can capture the characteristics of more vulnerable sectors of a population, but may bias the picture of population level disease risk. When sampling network data, an incomplete description of the population may arise leading to biased estimates of between-host connectivity. Avian influenza (AI) control planning in Great Britain (GB) provides one example where network data for the poultry industry (the Poultry Network Database or PND), targeted large premises and is consequently demographically biased. Exposing the effect of such biases on the geographical distribution of network properties could help target future poultry network data collection exercises. These data will be important for informing the control of potential future disease outbreaks. The PND was used to compute between-farm association frequencies, assuming that farms sharing the same slaughterhouse or catching company, or through integration, are potentially epidemiologically linked. The fitted statistical models were extrapolated to the Great Britain Poultry Register (GBPR); this dataset is more representative of the poultry industry but lacks network information. This comparison showed how systematic biases in the demographic characterisation of a network, resulting from targeted sampling procedures, can bias the derived picture of between-host connectivity within the network. With particular reference to the predictive modeling of AI in GB, we find significantly different connectivity patterns across GB when network estimates incorporate the more demographically representative information provided by the GBPR; this has not been accounted for by previous epidemiological analyses. We recommend ranking geographical regions, based on relative confidence in extrapolated estimates, for prioritising further data collection. Evaluating whether and how the between-farm association frequencies impact on the risk of between-farm transmission will be the focus of future work.

  3. Developments in rubber technology 2 synthetic rubbers

    CERN Document Server

    Lee, K


    This book is intended for those people who have a knowledge or understanding of rubber materials and processes but who wish to update their knowledge. It should be read in conjunction with Developments in Rubber Technology-l as that volume discussed developments in natural rubber and selected special purpose synthetic rubbers as well as additives. The authors have been selected for their expertise in each particular field and we, as editors, would like to express our appreciation to the individual authors and also to their companies. Such a book would be impossible to produce without such active cooperation as we have received. Volumes 1 and 2 of Developments in Rubber Technology cover rubbers which are processed and vulcanised in the traditional manner. It is appreciated that the omission of non-vulcanised rubber materials (the so­ called thermoplastic elastomers) will be unwelcome to many readers but it is intended, because of the size of the subject, to cover these materials in a subsequent volume. A.W. K...

  4. British Columbia (United States)

    Walton, Gerald


    The province of British Columbia has a dubious history where support for lesbian, gay, bisexual, and transgendered (LGBT) issues in education is concerned. Most notable is the Surrey School Board's decision in 1997 to ban three picture books for children that depict families with two moms or two dads. The North Vancouver School Board has also…

  5. Silencing the lettuce homologs of small rubber particle protein does not influence natural rubber biosynthesis in lettuce (Lactuca sativa). (United States)

    Chakrabarty, Romit; Qu, Yang; Ro, Dae-Kyun


    Natural rubber, cis-1,4-polyisoprene, is an important raw material in chemical industries, but its biosynthetic mechanism remains elusive. Natural rubber is known to be synthesized in rubber particles suspended in laticifer cells in the Brazilian rubber tree (Hevea brasiliensis). In the rubber tree, rubber elongation factor (REF) and its homolog, small rubber particle protein (SRPP), were found to be the most abundant proteins in rubber particles, and they have been implicated in natural rubber biosynthesis. As lettuce (Lactuca sativa) can synthesize natural rubber, we utilized this annual, transformable plant to examine in planta roles of the lettuce REF/SRPP homologs by RNA interference. Among eight lettuce REF/SRPP homologs identified, transcripts of two genes (LsSRPP4 and LsSRPP8) accounted for more than 90% of total transcripts of REF/SRPP homologs in lettuce latex. LsSRPP4 displays a typical primary protein sequence as other REF/SRPP, while LsSRPP8 is twice as long as LsSRPP4. These two major LsSRPP transcripts were individually and simultaneously silenced by RNA interference, and relative abundance, polymer molecular weight, and polydispersity of natural rubber were analyzed from the LsSRPP4- and LsSRPP8-silenced transgenic lettuce. Despite previous data suggesting the implications of REF/SRPP in natural rubber biosynthesis, qualitative and quantitative alterations of natural rubber could not be observed in transgenic lettuce lines. It is concluded that lettuce REF/SRPP homologs are not critically important proteins in natural rubber biosynthesis in lettuce. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Chrome-tanned leather shavings as a filler of butadiene-acrylonitrile rubber. (United States)

    Przepiórkowska, A; Chrońska, K; Zaborski, M


    The noxious wastes from the tanning industry such as chrome-tanned leather shavings were used as the only filler of rubber mixes containing carboxylated butadiene-acrylonitrile rubber (XNBR) or butadiene-acrylonitrile rubber (NBR), and a dispersing agent Limanol PEV (Schill & Seilacher). The best form addition of leather powder to the rubber mixes is mixed the waste protein with zinc oxide. The leather powder added to the rubber mixes improves the mechanical properties: tensile strength (T(s)), elongation at break (epsilon(b)) and increase the cross-linking density of carboxylated XNBR and NBR rubber mixes. Satisfactory results of these studies are presented in this work.

  7. A study of amino acid modifiers in guayule natural rubber (United States)

    Natural rubber from the Hevea tree is a critical agricultural material vital to United States industry, medicine, and defense, yet the country is dependent on imports to meet domestic needs. Guayule, a desert shrub indigenous to the US, is under development as an alternative source of natural rubber...


    African Journals Online (AJOL)

    Journal or Agriculture in Social Research (JASR) v01. 7, No.2, 2007 a '. REVIEW or POST- HARVEST DETERIORATION or RUBBER SEEDS ~. CLARA LEYIBO IGELEKE. AND vrcronmooun omorwsr. ABSTRACT , r r ~ ' Rubber seeds have potential use as a source of industrial oil as well as a protein supplement for use in ...

  9. Investigating the tension load of rubber composites by impact ...

    Indian Academy of Sciences (India)

    capacity conveyors or those working under heavy conditions. (sharp slope and high speed, with big lengths to transport), which need a very good breaking strength, special flexibility and high reliability [9]. Rubber industry often faces the prob- lem of wear of rubber parts. The wear of CBs is character- ized by abrasion [10].

  10. Characterization of some selected vulcanized and raw silicon rubber materials (United States)

    Sasikala, A.; Kala, A.


    Silicone Rubber is a high need of importance of Medical devices, Implants, Aviation and Aerospace wiring applications. Silicone rubbers are widely used in industry, and there are in multiple formulations. A raw and vulcanized silicone rubber Chemical and Physical structures of particles was confirmed and mechanical strength has been analyzed by FTIR spectroscopy. Thermal properties studied from Thermo Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) analysis. Activation energy of the rubber materials were calculated using Broido method, Piloyon-Novikova relation and coats-Red fern methods.

  11. Natural rubber: leather composites

    Directory of Open Access Journals (Sweden)

    K. Ravichandran


    Full Text Available Leather is a fibrous protein consisting of collagen in a three dimensionally crosslinked network. Chrome tanning of leather improves the appearance of leather but at the same time emits both solid and liquid chrome leather wastes. Scrap rubber recycling using untreated and neutralized leather fibrous particles in natural rubber has been studied. Vulcanization, mechanical, morphological and swelling properties of the natural rubber - scrap rubber composites containing neutralized leather have been discussed. Use of chrome leather particles has been found to improve the consumption of scrap rubber powder in natural rubber formulations. Polymer composites based on leather wastes as fillers are reported to be useful for many applications such as in construction materials, automobile interior moldings, heat and sound insulating boards, shoe soles, flooring materials and moldings with good anti-static properties, air permeability and good appearances.

  12. “Working the System”—British American Tobacco's Influence on the European Union Treaty and Its Implications for Policy: An Analysis of Internal Tobacco Industry Documents (United States)

    Smith, Katherine E.; Fooks, Gary; Collin, Jeff; Weishaar, Heide; Mandal, Sema; Gilmore, Anna B.


    Background Impact assessment (IA) of all major European Union (EU) policies is now mandatory. The form of IA used has been criticised for favouring corporate interests by overemphasising economic impacts and failing to adequately assess health impacts. Our study sought to assess how, why, and in what ways corporations, and particularly the tobacco industry, influenced the EU's approach to IA. Methods and Findings In order to identify whether industry played a role in promoting this system of IA within the EU, we analysed internal documents from British American Tobacco (BAT) that were disclosed following a series of litigation cases in the United States. We combined this analysis with one of related literature and interviews with key informants. Our analysis demonstrates that from 1995 onwards BAT actively worked with other corporate actors to successfully promote a business-oriented form of IA that favoured large corporations. It appears that BAT favoured this form of IA because it could advance the company's European interests by establishing ground rules for policymaking that would: (i) provide an economic framework for evaluating all policy decisions, implicitly prioritising costs to businesses; (ii) secure early corporate involvement in policy discussions; (iii) bestow the corporate sector with a long-term advantage over other actors by increasing policymakers' dependence on information they supplied; and (iv) provide businesses with a persuasive means of challenging potential and existing legislation. The data reveal that an ensuing lobbying campaign, largely driven by BAT, helped secure binding changes to the EU Treaty via the Treaty of Amsterdam that required EU policymakers to minimise legislative burdens on businesses. Efforts subsequently focused on ensuring that these Treaty changes were translated into the application of a business orientated form of IA (cost–benefit analysis [CBA]) within EU policymaking procedures. Both the tobacco and chemical

  13. "Working the system"--British American tobacco's influence on the European union treaty and its implications for policy: an analysis of internal tobacco industry documents. (United States)

    Smith, Katherine E; Fooks, Gary; Collin, Jeff; Weishaar, Heide; Mandal, Sema; Gilmore, Anna B


    Impact assessment (IA) of all major European Union (EU) policies is now mandatory. The form of IA used has been criticised for favouring corporate interests by overemphasising economic impacts and failing to adequately assess health impacts. Our study sought to assess how, why, and in what ways corporations, and particularly the tobacco industry, influenced the EU's approach to IA. In order to identify whether industry played a role in promoting this system of IA within the EU, we analysed internal documents from British American Tobacco (BAT) that were disclosed following a series of litigation cases in the United States. We combined this analysis with one of related literature and interviews with key informants. Our analysis demonstrates that from 1995 onwards BAT actively worked with other corporate actors to successfully promote a business-oriented form of IA that favoured large corporations. It appears that BAT favoured this form of IA because it could advance the company's European interests by establishing ground rules for policymaking that would: (i) provide an economic framework for evaluating all policy decisions, implicitly prioritising costs to businesses; (ii) secure early corporate involvement in policy discussions; (iii) bestow the corporate sector with a long-term advantage over other actors by increasing policymakers' dependence on information they supplied; and (iv) provide businesses with a persuasive means of challenging potential and existing legislation. The data reveal that an ensuing lobbying campaign, largely driven by BAT, helped secure binding changes to the EU Treaty via the Treaty of Amsterdam that required EU policymakers to minimise legislative burdens on businesses. Efforts subsequently focused on ensuring that these Treaty changes were translated into the application of a business orientated form of IA (cost-benefit analysis [CBA]) within EU policymaking procedures. Both the tobacco and chemical industries have since employed IA in

  14. "Working the system"--British American tobacco's influence on the European union treaty and its implications for policy: an analysis of internal tobacco industry documents.

    Directory of Open Access Journals (Sweden)

    Katherine E Smith


    Full Text Available Impact assessment (IA of all major European Union (EU policies is now mandatory. The form of IA used has been criticised for favouring corporate interests by overemphasising economic impacts and failing to adequately assess health impacts. Our study sought to assess how, why, and in what ways corporations, and particularly the tobacco industry, influenced the EU's approach to IA.In order to identify whether industry played a role in promoting this system of IA within the EU, we analysed internal documents from British American Tobacco (BAT that were disclosed following a series of litigation cases in the United States. We combined this analysis with one of related literature and interviews with key informants. Our analysis demonstrates that from 1995 onwards BAT actively worked with other corporate actors to successfully promote a business-oriented form of IA that favoured large corporations. It appears that BAT favoured this form of IA because it could advance the company's European interests by establishing ground rules for policymaking that would: (i provide an economic framework for evaluating all policy decisions, implicitly prioritising costs to businesses; (ii secure early corporate involvement in policy discussions; (iii bestow the corporate sector with a long-term advantage over other actors by increasing policymakers' dependence on information they supplied; and (iv provide businesses with a persuasive means of challenging potential and existing legislation. The data reveal that an ensuing lobbying campaign, largely driven by BAT, helped secure binding changes to the EU Treaty via the Treaty of Amsterdam that required EU policymakers to minimise legislative burdens on businesses. Efforts subsequently focused on ensuring that these Treaty changes were translated into the application of a business orientated form of IA (cost-benefit analysis [CBA] within EU policymaking procedures. Both the tobacco and chemical industries have since


    African Journals Online (AJOL)


    . Nigerian grown rubber in south eastern state of Abia, so as to relate the wood quality with a range of industrial usefulness of the species and the possibility of controlling the wood fibre features silviculturally and genetically.

  16. The Current Situation and the Development Strategies of Rubber


    HUANG, Huide; Zhang, Wanzhen; Zhang, Xizhu; HUANG, Haolun


    This article describes the distribution, member structure and industrial operation structure of the rubber farmer cooperatives in Hainan Province, and points out some problems in the cooperatives, such as small member scale, unbalanced regional development, lack of standardization in operation, and industrial operation structure imbalance. Finally some development strategies are put forward as follows: building large-scale cooperatives; attaching importance to the development of rubber farmer...

  17. Polypropylene/ethylene-propylene rubber (PP/EPR blends for the automotive industry: Basic correlations between EPR-design and shrinkage

    Directory of Open Access Journals (Sweden)

    G. D. Potter


    Full Text Available The influence of the phase morphology on the shrinkage of injection molded plates from reactor based PP/EPR blends was investigated using a model series. The morphology of the dispersed phase – in terms of size and shape of the rubber particles as determined from scanning electron microscopy (SEM – was found to correlate fairly well with the shrinkage determined in the flow and transverse direction of injection molded plates. In this respect it turned out to be elementary to consider the anisotropy of the particles rather than their average size alone. Additionally, the effect of the EPR design on the coefficient of linear thermal expansion (CLTE was evaluated and brought into a relationship with the blend morphology.

  18. Multilayer graphene rubber nanocomposites (United States)

    Schartel, Bernhard; Frasca, Daniele; Schulze, Dietmar; Wachtendorf, Volker; Krafft, Bernd; Morys, Michael; Böhning, Martin; Rybak, Thomas


    Multilayer Graphene (MLG), a nanoparticle with a specific surface of BET = 250 m2/g and thus made of only approximately 10 graphene sheets, is proposed as a nanofiller for rubbers. When homogenously dispersed, it works at low loadings enabling the replacement of carbon black (CB), increase in efficiency, or reduction in filler concentration. Actually the appropriate preparation yielded nanocomposites in which just 3 phr are sufficient to significantly improve the rheological, curing and mechanical properties of different rubbers, as shown for Chlorine-Isobutylene-Isoprene Rubber (CIIR), Nitrile-Butadiene Rubber (NBR), Natural Rubber (NR), and Styrene-Butadiene Rubber (SBR). A mere 3 phr of MLG tripled the Young's modulus of CIIR, an effect equivalent to 20 phr of carbon black. Similar equivalents are observed for MLG/CB mixtures. MLG reduces gas permeability, increases thermal and electrical conductivities, and retards fire behavior. The later shown by the reduction in heat release rate in the cone calorimeter. The higher the nanofiller concentration is (3 phr, 5 phr, and 10 phr was investigated), the greater the improvement in the properties of the nanocomposites. Moreover, the MLG nanocomposites improve stability of mechanical properties against weathering. An increase in UV-absorption as well as a pronounced radical scavenging are proposed and were proved experimentally. To sum up, MLG is interesting as a multifunctional nanofiller and seems to be quite ready for rubber development.

  19. British colonial rule and food crops production in Esan, Benin ...

    African Journals Online (AJOL)

    After the conquest and imposition of colonial rule, the British authorities imposed new demands on the people; the production of raw materials such as rubber, palm oil and kernels among others. The production of these raw materials impeded the cultivation of food crop in Esan. This paper therefore, examines the factors ...

  20. Allergic reactions to rubber condoms.


    Rademaker, M; Forsyth, A


    With the increased use of condoms, contact dermatitis to rubber is being seen more often. To develop a rubber condom suitable for use by rubber sensitive people, a "hypoallergenic" condom, which is washed in ammonia to reduce the residues of rubber accelerators, has been manufactured. Fifty patients allergic to various rubber accelerators were patch tested with an ordinary condom and the new washed condom. Fifty patients undergoing routine patch test investigation who were not allergic to rub...

  1. Sugarcane bagasse ash: new filler to natural rubber composite

    Directory of Open Access Journals (Sweden)

    Renivaldo José dos Santos


    Full Text Available Waste recycling has been the subject of numerous scientific researches regarding the environmental care. This paper reports the redirecting of sugarcane bagasse ash (SBA as new filler to natural rubber (NR/SBA. The NR/SBA composites were prepared using an opened cylinder mixer to incorporate the vulcanization agents and different proportions of residue (SBA. The ash contains about 70-90% of inorganic compounds, with silica (SiO2 being the main compound. The SBA incorporation improved the mechanical properties of the vulcanized rubber. Based on these results, a new use is proposed for the agro-industry organic waste to be implemented in the rubber vulcanization process, aimed at improving the rubber physical properties as well as decreasing the prices of natural rubber composites.

  2. Radiation vulcanization of natural rubber latex sensitized with commercial gases

    Energy Technology Data Exchange (ETDEWEB)

    Chirinos, H.; Lugao, A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)


    The industrial activities using natural rubber latex are fully compatible with rural areas in Amazon and other places in Brazil, as well as in other tropical countries. However the classical sulfur vulcanization presents many occupational problems for the workers in rural areas. Radiation vulcanization of natural rubber latex is a much more friendly process as sulfur compounds are not needed for crosslinking, although chemicals as acrylate monomers, particularly multifunctional acrylates are still used as sensitizers for radiation processes. Two commercial gases, acetylene and butadiene, were selected as sensitizers for the radiation vulcanization of natural rubber latex instead of acrylates. These gases accelerate the crosslinking rates of the cure process and lower the radiation dose required to achieve vulcanization of natural rubber latex and improve the mechanical properties to reduce the tackiness of rubber goods. (author)

  3. The rubber tree genome shows expansion of gene family associated with rubber biosynthesis. (United States)

    Lau, Nyok-Sean; Makita, Yuko; Kawashima, Mika; Taylor, Todd D; Kondo, Shinji; Othman, Ahmad Sofiman; Shu-Chien, Alexander Chong; Matsui, Minami


    Hevea brasiliensis Muell. Arg, a member of the family Euphorbiaceae, is the sole natural resource exploited for commercial production of high-quality natural rubber. The properties of natural rubber latex are almost irreplaceable by synthetic counterparts for many industrial applications. A paucity of knowledge on the molecular mechanisms of rubber biosynthesis in high yield traits still persists. Here we report the comprehensive genome-wide analysis of the widely planted H. brasiliensis clone, RRIM 600. The genome was assembled based on ~155-fold combined coverage with Illumina and PacBio sequence data and has a total length of 1.55 Gb with 72.5% comprising repetitive DNA sequences. A total of 84,440 high-confidence protein-coding genes were predicted. Comparative genomic analysis revealed strong synteny between H. brasiliensis and other Euphorbiaceae genomes. Our data suggest that H. brasiliensis's capacity to produce high levels of latex can be attributed to the expansion of rubber biosynthesis-related genes in its genome and the high expression of these genes in latex. Using cap analysis gene expression data, we illustrate the tissue-specific transcription profiles of rubber biosynthesis-related genes, revealing alternative means of transcriptional regulation. Our study adds to the understanding of H. brasiliensis biology and provides valuable genomic resources for future agronomic-related improvement of the rubber tree.

  4. Mutagenicity of rubber vulcanization gases in Salmonella typhimurium. (United States)

    Hedenstedt, A; Ramel, C; Wachtmeister, C A


    Gases formed by rubber and rubber additives in the vulcanization process were collected with a laboratory-scale glass apparatus. Mutagenicity testing of the vulcanization gases by the Salmonella/microsome test was conducted with strains TA1535, TA1538, TA98, and TA100 in the absence and presence of a metabolizing system from rat liver homogenates. The mutagenicity of gases derived by heating chloroprene rubber and ethylene propylene rubber was established with both base substitution- and frameshift-sensitive strains and that of a styrene-butadiene rubber was established with the base substitution-sensitive stain TA100. Tests on pyrolysis gases from a butadiene acrylonitrile rubber revealed only toxic effects. Curing systems, additives, and filling materials from various sources were represented in the material. Gases were collected at temperature levels corresponding to both mixing and curing of these particular rubbers in the industrial operations. Attempts were made to correlate the mutagenicity of the gases to the presence of mutagenic components in the rubber mixtures.

  5. Mortalidade por câncer em trabalhadores da indústria da borracha de São Paulo Cancer mortality among rubber industry workers in São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Hélio Neves


    Full Text Available OBJETIVO: Avaliar as mortes por câncer em trabalhadores da indústria da borracha de acordo com o tamanho da empresa. MÉTODOS: Coorte histórica com 9.188 trabalhadores masculinos, matriculados em sindicato de trabalhadores da indústria de borracha do Estado de São Paulo entre 1975 e 1985, sobreviventes em janeiro de 1990 e acompanhados até o final de 2000. As mortes por câncer foram comparadas internamente à coorte, cujos membros foram subdivididos em estratos por porte e sub-ramo da empresa, setor de trabalho e qualificação profissional. A abordagem por conjuntos de risco e regressão logística condicional foi utilizada para o cálculo dos riscos relativos, ajustados por idade, tempo desde o primeiro emprego e tempo de trabalho na indústria da borracha. RESULTADOS: Quando comparados aos empregados de grandes empresas, trabalhadores de pequenas empresas mostraram excesso de mortes por todos tipos de câncer (RR=2,33; IC 95%: 0,90-6,03; tumores de estômago (RR=3,47; IC 95%: 2,57-4,67 e do trato aero-digestivo superior (RR=2,49; IC 95%: 1,78-3,48. Identificou-se excesso de mortes por câncer nos trabalhadores dos setores de manutenção (RR=2,23; IC 95%: 0,73-6,76; expedição, armazenamento e transporte (RR=2,97; IC 95%: 0,77-11,38; e produção (RR=3,51; IC 95%: 1,07-11,57, comparados aos trabalhadores dos setores administrativos. CONCLUSÕES: Os resultados mostram evidências de aumento do risco de tumores de estômago e do trato aero-digestivo superior e, possivelmente, por câncer em geral em trabalhadores de empresas de pequeno porte da indústria da borracha quando comparados aos trabalhadores das grandes empresas.OBJECTIVE: To investigate cancer deaths among rubber industry workers according to company size. METHODS: This historical cohort study included 9,188 male workers, engaged as members of a workers' union in São Paulo, Southeastern Brazil, between 1975 and 1985, alive in January 1990 and followed until the end of 2000

  6. Occupational vitiligo due to unsuspected presence of phenolic antioxidant byproducts in commercial bulk rubber

    Energy Technology Data Exchange (ETDEWEB)

    O' Malley, M.A.; Mathias, C.G.; Priddy, M.; Molina, D.; Grote, A.A.; Halperin, W.E.


    We investigated the occurrence of cutaneous depigmentation (vitiligo) among employees of a company that manufactured hydraulic pumps. The interiors of these pumps were injection-molded with rubber. We identified a small but significant cluster of vitiligo cases among a group of employees who frequently handled the rubber used in this injection molding process. Although none of the additives specified in the rubber formulations was a phenolic or catecholic derivative, known to be potential causes of chemically induced vitiligo, gas chromatographic analysis identified a para-substituted phenol (2,4-di-tert-butylphenol, DTBP) in solid samples of the most frequently used rubber. Surface wipe analysis confirmed that workers could be exposed to DTBP from simple handling of the rubber. We subsequently established that the solid bulk rubber used as the base in these stock rubber formulations contained both DTBP and smaller quantities of p-tert-butylphenol. Both had formed as unsuspected byproducts during chemical synthesis of two antioxidants added to the solid bulk rubber by a major rubber supplier. We conclude that the unsuspected presence of potential chemical depigmenting agents in solid bulk rubber, from which industrial rubber products are formulated, may contribute to the occurrence of occupational vitiligo, and that a simple review of ingredients in rubber formulations is inadequate to detect their presence.

  7. Preparation of magnetic rubber with high mechanical properties by latex compounding method

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Chunlin [Shanxi Province Key Laboratory of Functional Nanocomposites, North University of China, Taiyuan 030051 (China); College of Materials Science and Engineering, North University of China, Taiyuan 030051 (China); Gao, Li; Yu, Hailing [Shanxi Province Key Laboratory of Functional Nanocomposites, North University of China, Taiyuan 030051 (China); Sun, Youyi, E-mail: [Shanxi Province Key Laboratory of Functional Nanocomposites, North University of China, Taiyuan 030051 (China); College of Materials Science and Engineering, North University of China, Taiyuan 030051 (China); Yao, Junru; Zhao, Guizhe [Shanxi Province Key Laboratory of Functional Nanocomposites, North University of China, Taiyuan 030051 (China); Liu, Yaqing, E-mail: [Shanxi Province Key Laboratory of Functional Nanocomposites, North University of China, Taiyuan 030051 (China); College of Materials Science and Engineering, North University of China, Taiyuan 030051 (China)


    the magnetic rubber based on Fe{sub 3}O{sub 4} nanoparticles and nature rubber were prepared by latex compounding method, in which stable Fe{sub 3}O{sub 4} aqueous solutions were mixed with natural rubber latex and additives. This process was fast, versatile, reliable, safe, environmentally friendly and inexpensive. What’s more, it was found that the magnetic and mechanical properties of magnetic rubber increased together with increase in doping content of Fe{sub 3}O{sub 4} nanoparticles. Especially, it was demonstrated that the tensile strength (25.0 Mpa) of magnetic rubber was improved to be 478.0% comparing to neat natural rubber (5.2 Mpa), which was 5 times higher than maximal value reported in previous work. At the same time, the magnetic rubber revealed better thermal stability and solvent resistance comparing to the neat natural rubber, too. The work dose not only provides a new way to environmentally friendly preparation of magnetic rubber at low temperature, but also improve the mechanical and magnetic properties of magnetic rubber applied in industry. - Highlights: • The magnetic rubber was prepared by a latex compounding method. • The magnetic rubber exhibited high mechanical properties. • The mechanism of high mechanical properties was investigated by the NMR.

  8. British Capital, Industry and Perseverance’ versus Dutch ‘Old School’?: The Dutch Atlantic and the Takeover of Berbice, Demerara and Essequibo, 1750-1815

    Directory of Open Access Journals (Sweden)

    Gert Oostindie


    Full Text Available Recent historiography has reconsidered the idea that the Dutch role in the early modern Atlantic was of little significance, particularly in comparison to the accomplishments of the Dutch East India Company (voc in Asia. Revisionist studies have emphasised that in spite of the limited and fragmented nature of the Dutch Atlantic ‘empire’, the Atlantic contribution to the Dutch economy was significant and possibly even greater than the voc’s share. Moreover, this scholarship stresses the vital role of Dutch Atlantic colonies (Curaçao and St Eustatius, (partly Jewish networks and individuals in connecting the various subempires of the Atlantic. While Oostindie subscribes to many of these conclusions, he argues against excessive revisionism. His analysis of the development of the lesser Dutch Guianas, adjacent to Suriname, is used as a counter-weight to this revisionist impulse. He demonstrates that the spectacular economic and demographic development of these colonies was due mainly to British and (British American involvement culminating in the eventual British takeover of ‘Guiana’.


    Directory of Open Access Journals (Sweden)

    Silvano A. Wueschner


    Full Text Available This paper examines the controversy arising out of Great Britain’s decision to implement the Stevenson plan. It examines, in particular, the role played by Herbert Hoover, both behind the scenes and in an effort to affect the repeal of the Stevenson scheme and at the same time to encourage and support the development of new sources of rubber under the control of American producers. During the period 1920-1922 rubber producing countries were confronted by the specter of overproduction. The existence of even a short term oversupply coupled with the business slump, a reaction from the war, led to a decline in the price of rubber. British producers succeeded in inducing the British Colonial authorities to support a scheme whereby rubber exports would be regulated in order to bring about an increase in the price of rubber. This plan, developed by the Stevenson Committee, called for a small minimum tax on all exports. Moreover, it soughtto limit production by establishing a quota based on the actual production of rubber during the 1919-1920 growing season. A progressive tax was applied to exports beyond standard production. American reaction to the scheme was varied. Secretary of Commerce Hoover, while publicly stating that the price of rubber had been low and was supportive of efforts to regulate production, behind the scenes showed a great deal of concern about the actions of the British government in regulating a commodity of which the United States was the single largest consumer. He was also linked, by some, to the idea that Great Britain sought to pay its war debt to the United States through the application of this tax. Much was made in American newspapers and the British press about Hoover’s criticism of British rubber restrictions. He was not opposed to regulating the supply of rubber, but only to the involvement of a government in the process, especially when it affected American producers and consumers. In response he proposed a scheme

  10. The Long-Term Effectiveness of Chemical vs. Polymeric Antiozonants in Rubber (United States)


    August 1954. 2. Lerner, M.E., Rubber Age. 105, 57, December 1973. 3. Buist, J., British Patent 939, 359 ( Application made in Canada, No. 802, 137...compound is EPDM. The effectiveness of EPDM as an 15 Bergstrom, E.W., "Loss of Antiozonant Efficacy in Butadiene-Styrene ( SBR ) Rubber After Shelf Storage...Patent 939, 359, ( Application made in Canada No. 802, 137) June 29, 1960. 4. Sutton, M.S. Rubber World. 149. 62, 1964. 5. Mitchell, J.M., Kindle

  11. Pilot scale experiment on aeration control system for upgrading single-stage activated sludge process for latex rubber industrial wastewater: Phase I:operational problems of using online sensors

    Directory of Open Access Journals (Sweden)

    Wanrudee Wanseng


    Full Text Available The aim of this experiment was to upgrade the operation of conventional activated sludge treatment plants to save aeration energy and at the same time to provide better utilization of existing plant capacity for nutrient removal without major financial investment. In this study, pilot-scale experiments of the single stage activated sludge process (ASP as operated in existing ASP in southern Thailand, were investigated under conditions of simultaneous nitrification-denitrification. This first stage of the experiments was to observe the possibility of using oxidation-reduction potential (ORP for aeration control in treatment plant fed with the wastewater from the latex rubber industry. Wastewater from the representative factory contained high carbon and solids. The F/M ratio was up to 1.5 kg of COD/day/kg of MLSS. The results proved that the ORP was greatly affected by the change in air supply. However, it was also affected by the fluctuation of wastewater temperature, which contributed to the bulking sludge problem.

  12. Improved properties of dissimilar rubber-rubber blends using plasma polymer encapsulated curatives : a novel surface modification method to improve co-vulcanization

    NARCIS (Netherlands)

    Guo, R.


    In industrial applications, different rubber types are often blended to fine-tune or optimize the property portfolio required for successful performance of articles. Considering the complexity of a rubber blend compound, wherein numerous additives are involved, vulcanization or cure mismatch often

  13. The use of styrene-butadiene rubber waste as a potential filler in nitrile rubber: order of addition and size of waste particles


    Baeta,D. A.; Zattera,J. A.; Oliveira,M. G.; Oliveira,P. J.


    Styrene-butadiene rubber (SBR) has large applications in the shoe industry, especially as expanded sheets used to produce insoles and inner soles. According to TG analysis, the rubber content in SBR residues (SBR-r) was found to be around 26-wt%. Based on that data, a cost-effective technique for the reuse of SBR-r in Nitrile rubber (NBR) was developed. Later, the effect of SBR-r on the cure behavior, mechanical performance, swelling, and crosslink density of reused rubber was investigated, w...

  14. Microcellular foaming of silicone rubber with supercritical carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Hong, In-Kwon; Lee, Sangmook [Dankook University, Youngin (Korea, Republic of)


    In spite of great concern on the industrial application of microcellular silicone rubber foams, such as in electric and medical devices, only a few works can be found about the foaming of silicone rubber. In this study, microcellular silicone rubber foams with a cell size of 12 µm were successfully prepared with curing by heat and foaming by supercritical CO{sub 2} as a green blowing agent. The microcellular silicone rubber foams exhibited a well-defined cell structure and a uniform cell size distribution. The crosslinking and foaming of silicone rubber was carried out separately. After foaming, the silicone rubber foam was cross-linked again to stabilize the foam structure and further improve its mechanical properties. Foaming process of cross-linked silicone rubber should be designed carefully based on the viscoelastic properties because of its elastic volume recovery in the atmosphere. The basic crosslinking condition for small cell size and high cell density was obtained after investigating the rheological behavior during crosslinking.

  15. Development of rubber?enriched dandelion varieties by metabolic engineering of the inulin pathway


    Stolze, A.; Wanke, A.; van Deenen, N.; Geyer, R.; PRÜFER, D.; Schulze Gronover, C.


    Summary Natural rubber (NR) is an important raw material for a large number of industrial products. The primary source of NR is the rubber tree Hevea brasiliensis, but increased worldwide demand means that alternative sustainable sources are urgently required. The Russian dandelion (Taraxacum koksaghyz Rodin) is such an alternative because large amounts of NR are produced in its root system. However, rubber biosynthesis must be improved to develop T.?koksaghyz into a commercially feasible cro...

  16. Vulcanization of Rubber

    Indian Academy of Sciences (India)

    Vulcanization of Rubber - How to Alter Molecular Structure and Influence Physical Properties. Ch S S R Kumar Avinash M Nijasure. General Article Volume 2 Issue 4 April 1997 pp 55-59. Fulltext. Click here to view fulltext PDF. Permanent link: Author Affiliations.

  17. Vulcanization of Rubber

    Indian Academy of Sciences (India)

    plastic. These attractive physical properties of vulcanized rubber have revolutionised its applications. Modern Improvements. The vulcanization process has undergone several modifications since its discovery. A typical process is shown in Box 1. It may be noted that many additives are included. These have been chosen to ...

  18. Influence of Rock Properties on Wear of M and SR Grade Rubber with Varying Normal Load and Sliding Speed

    Directory of Open Access Journals (Sweden)

    Pal Samir Kumar


    Full Text Available Rubbers are interesting materials and are extensively used in many mining industries for material transportation. Wear of rubber is a very complex phenomenon to understand. The present study aims to explain the influence of rock properties on wear of M and SR grade rubber used in top cover of conveyor belts. Extensive laboratory experiments were conducted under four combinations of normal load and sliding speed. The wear of both the rubber types were analyzed based on the rock properties like shear strength, abrasivity index and fractal dimension. A fully instrumented testing set up was used to study the wear of rubber samples under different operating conditions. In general, wear was higher for M grade rubber compared to SR grade rubber. Increase in shear strength of rocks depicts decreasing trend for the wear of M and SR grade rubber at lower load conditions. Moreover, a higher load combination displays no definite trend in both the rubbers. The strong correlation between the wear of rubber and frictional power for all rubber-rock combinations has given rise to the parameter A, which reflects the relative compatibility between the rubber and rock. Increase of Cerchar’s Abrasivity Index of rocks shows gradual enhancement in wear for M grade rubber in all the load and speed combinations whereas, it fails in SR grade rubber due to its higher strength. The wear of rubber tends to decrease marginally with the surface roughness of rocks at highest normal load and sliding speed in M grade rubber. However, the wear of M and SR grade rubber is influenced by the surface roughness of rocks.

  19. British Sign Name Customs (United States)

    Day, Linda; Sutton-Spence, Rachel


    Research presented here describes the sign names and the customs of name allocation within the British Deaf community. While some aspects of British Sign Language sign names and British Deaf naming customs differ from those in most Western societies, there are many similarities. There are also similarities with other societies outside the more…


    The improvement of rubber tree species is of key importance due to the worldwide market demand of this renewable material essential for several types of industries. The thermal performance of natural rubber produced from new clones of IAC 300 series, and the Malaysian RRIM 600 clone (used as control...

  1. A study of protein and amino acids in guayule natural rubber (United States)

    Natural rubber (NR) from Hevea brasiliensis (the Hevea rubber tree) is a critical agricultural material vital to United States industry, medicine, and defense, yet the country is dependent on NR imports to meet domestic needs. Parthenium argentatum (guayule), a woody desert shrub indigenous to the U...


    NARCIS (Netherlands)



    Silicone rubber is used for a wide variety of biomedical and industrial applications due to its good mechanical properties, combined with a hydrophobic surface. Frequently, however, it is desirable to alter the surface hydrophobicity of silicone rubber. Often this is done by plasma treatments but

  3. Historical and Recent Achievements in the Field of Microbial Degradation of Natural and Synthetic Rubber (United States)

    Yikmis, Meral


    This review intends to provide an overview of historical and recent achievements in studies of microbial degradation of natural and synthetic rubber. The main scientific focus is on the key enzymes latex-clearing protein (Lcp) from the Gram-positive Streptomyces sp. strain K30 and rubber oxygenase A (RoxA) from the Gram-negative Xanthomonas sp. strain 35Y, which has been hitherto the only known rubber-degrading bacterium that does not belong to the actinomycetes. We also emphasize the importance of knowledge of biodegradation in industrial and environmental biotechnology for waste natural rubber disposal. PMID:22504822


    Directory of Open Access Journals (Sweden)

    P. S. Beliaev


    Full Text Available Summary. The article considers the problem of waste rubber industry through their recycling, compelling stakeholders to keep stocks of valuable raw rubber and improve our environment. The questions of the processes of thermal devulcanization of rubber crumb rubber products, and then use the resulting material (reclaimed rubber crumb as a modifier to improve the quality of road binder. The effect of technological parameters devulcanisation thermal (temperature and exposure time on the degree of devulcanization of crumb rubber. The question of the choice of environmentally friendly agents and emollients devulcanisation to speed the process flow. Researches modifications road binder Reclaimed rubber crumbs obtained under different conditions. The degree of influence of the content of reclaimed rubber crumb on the physico-mechanical properties of road binder bitumen BND 60/90. Studies have shown that the physical and mechanical properties of modified bitumen conform to standards of rubber bitumen binders in accordance with the recommendations of the firm "BITREK": introduction regeneration rata crumb rubber binder in the road leads to an increase in the softening temperature and the appearance of elasticity in the binder compared to the original bitumen and the values of penetration and elongation are within acceptable limits. Thus, the use of recycled materials, reduces the cost of producing a binder for pavement compared to peers.

  5. Residual stresses in rubber formed thermoplastic composites

    NARCIS (Netherlands)

    Wijskamp, Sebastiaan; Lamers, E.A.D.; Akkerman, Remko; Brucato, V.


    The rubber pressing process is applied for the rapid production of thermoplastic composite products. However, rubber pressed products show geometrical distortions, such as warpage, due to processinduced residual stresses. An experimental study is performed to measure the curvature after rubber

  6. Effect of quaternary ammonium salts in the process of extracting oil filled rubber from latex

    Directory of Open Access Journals (Sweden)

    N. S. Nikulina


    Full Text Available Currently, much attention is paid to the improvement of production technology of synthetic rubber. Much attention is given to rubber is produced by emulsion polymerization. This is due to the fact that rubbers produced by emulsion polymerization have a number of positive characteristics, and are widely used in the tire and rubber industry, in composite formulations for various purposes. In recent years, the technology of production of synthetic rubbers are widely used quaternary ammonium salts which are produced on an industrial scale. Application low and high molecular weight quaternary ammonium salts to reduce pollution of environ-mental protection, exclude the use of mineral salts without significant changes in the process flowsheet. It is found that quaternary ammonium salts react with the components of the emulsion system to form insoluble complexes, which are captured produced rubber crumb. However, Applications, quaternary salts in the manufacture of oil-filled rubber in the literature sources have not been given due attention. The study presents the results of research on the effect of the concentration of a coagulating agent, tempera tours and concentration of the dispersed phase in the process of coagulation of latex in the preparation of oil-filled rubber stamps SCS-30 ARKM-15. The concentration of the coagulating agent does not significantly affect the process of separation of the rubber from the latex. The process of isolation rubber latex is advantageously carried out at a reduced temperature. The concentration of the dispersed phase also provides material effect on the coagulation process. The lead researches mouthestablished that produced rubber, rubber compounds and vulcanizates based on these indicators correspond to their requirements.

  7. QENS investigation of filled rubbers

    CERN Document Server

    Triolo, A; Desmedt, A; Pieper, J K; Lo Celso, F; Triolo, R; Negroni, F; Arrighi, V; Qian, H; Frick, B


    The polymer segmental dynamics is investigated in a series of silica-filled rubbers. The presence of inert fillers in polymers greatly affects the mechanical and physical performance of the final materials. For example, silica has been proposed as a reinforcing agent of elastomers in tire production. Results from quasielastic neutron scattering and Dynamic Mechanical Thermal Analysis (DMTA) measurements are presented on styrene-ran-butadiene rubber filled with silica. A clear indication is obtained of the existence of a bimodal dynamics, which can be rationalized in terms of the relaxation of bulk rubber and the much slower relaxation of the rubber adsorbed on the filler surface. (orig.)

  8. Caracterização de artefatos elastoméricos obtidos por revulcanização de resíduo industrial de SBR (copolímero de butadieno e estireno Characterization of elastomeric artifacts obtained by revulcanization of SBR industrial waste (Styrene-butadiene Rubber

    Directory of Open Access Journals (Sweden)

    Tatiana Weber


    Full Text Available A reciclagem de resíduos de borracha é de extrema importância nos dias de hoje, tanto em relação aos impactos ambientais quanto à conservação de energia. Considerando que a maioria dos trabalhos publicados atualmente se refere à reciclagem de pneus, o objetivo deste trabalho foi desenvolver e caracterizar formulações contendo um tipo de resíduo industrial, proveniente da fabricação de perfis automotivos, à base de copolímero de butadieno e estireno (SBR para possível aplicação na própria empresa. As composições foram preparadas e caracterizadas pela determinação das propriedades térmicas (calorimetria diferencial de varredura, reológicas (analisador de processamento de borracha, reométricas (reômetria de disco oscilatório, mecânicas (resistência à tração e ao rasgamento, químicas (densidade de ligações cruzadas e morfológicas (microscopia eletrônica de varredura. Os resultados obtidos para as composições foram comparados aos de uma amostra controle, de mesma composição, que foi fornecida pela empresa geradora do resíduo de SBR. Os resultados mecânicos indicaram que o processo de revulcanização proposto foi efetivo. Os valores dos parâmetros de tensão na ruptura e resistência ao rasgamento foram de 70 e 50%, respectivamente, em relação aos valores encontrados para a amostra controle, indicando a possibilidade do uso desse resíduo em artefatos de menor exigência técnica.The recycling of waste rubber has very important significances, such as protection of the environment and conservation of energy. Considering that most of published works concerning this subject are about tire recycling, the objective of this work was to develop and characterize formulations containing a type of industrial waste, from the manufacture of automotive profiles, based on styrene-butadiene rubber (SBR for possible application in the industry. The compositions were formulated and characterized by thermal (differential

  9. "Rule of Thumb Methods No Longer Suffice": Development of British Coal Industry Education and Training 1900-circa 1970 and Lessons for Present-Day Education Policy-Makers (United States)

    Walker, Martyn A.


    This paper traces the origins and development of coal mining education and training in Britain from 1900 to the 1970s, by which time the coal industry had substantially declined. It looks at the progress from working-class self-help to national policy in support of education and training. The research makes use of college prospectuses and…

  10. Application of gamma irradiation for incorporation of rubber powder in the formulations of EPDM and natural rubber; Aplicacao da radiacao gama para incorporacao do po de borracha em formulacoes de borracha natural e EPDM

    Energy Technology Data Exchange (ETDEWEB)

    Kiyan, Ludmila Y.P.; Parra, Duclerc Fernandes; Lugao, Ademar Benevolo, E-mail: [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP/CQMA), Sao Paulo, SP (Brazil). Centro de Quimica e Meio Ambiente


    The objective of this work was to study the behavior of the recycling of rubber burrs in form of powder, of the rubber industry from EPDM rubber powder and natural rubber with SBR. The rubber powder was irradiated and reused in rubber artifacts formulations for classical vulcanization. The processed material was irradiated using a {sup 60}Co source in doses of 50, 100, 150 and 200 kGy and a dose rate of 5 kGy s-1 at room temperature. The radiation created devulcanization active sites for subsequent integration of the material (rubber powder) in formulations of commercial use. The processes were compared and their products characterized by analytical methods of the physical properties such as strength and elongation. Satisfactory results were found, noting a major spin-off of EPDM chain demonstrated by increased elongation.


    Directory of Open Access Journals (Sweden)

    Z. S. Shashok


    Full Text Available Summary. The results of studies of the elastomeric compositions based on natural rubber containing curatives different ratio "curing agent : vulcanization accelerator" listed in this article. Influence of the composition of the vulcanizing group on stress-strain and elastic- deformation properties of tire tread rubber was installed. It has been shown that a significant effect on thermo-oxidative aging of vulcanizates was the composition of the vulcanizing group. Results of studies resistance tread rubber to exposure to elevated temperatures were presented . Vulcanizates differing type and density by varying the cross-linking ratio of "curing agent : vulcanization accelerator" were obtained . Research results in the formation of rubber resistance and crack growth at different temperatures were presented. Revealed that the best education and resistance to tear propagation under normal conditions characterized by rubber ratio "curing agent : vulcanization accelerator" equal to 1.5:1. It has been established that a dynamic endurance study rubbers depends largely on the nature and concentration of the cross-linking cross-links and movable promote increase efficiency due to the grid and reduce the sulfidity rearrangement. During loading mode alternating deformations at elevated temperatures lability of polysulfide bonds negatively affects the performance of rubber, and the decisive role of providing strength and thermal cross-linking. It is shown that the performance of the spatial grid rubbers allow indirectly judge the dynamic vulcanizates endurance and predict performance rubbers at elevated temperatures under conditions of repeated cyclic deformation. Revealed that the vulcanizing system containing sulfur and vulcanization accelerator TBBS 1:2, promotes the formation of the optimal structure of vulcanized rubber , which provides the best resistance to repeated cyclic deformations in the operating temperatures of the tire.

  12. Earthquakes in British Columbia

    National Research Council Canada - National Science Library


    This pamphlet provides information about the causes of earthquakes, where earthquakes occur, British Columbia plate techtonics, earthquake patterns, earthquake intensity, geology and earthquake impact...

  13. Alternative sources of natural rubber

    NARCIS (Netherlands)

    Mooibroek, H.; Cornish, K.


    Rubber (cis-1,4-polyisoprene) is one of the most important polymers naturally produced by plants because it is a strategic raw material used in more than 40,000 products, including more than 400 medical devices. The sole commercial source, at present, is natural rubber harvested from the Brazilian


    African Journals Online (AJOL)


    Sep 2, 2010 ... Makurdi Benue State. Correspondence: ABSTRACT. Variations in the fibre length of rubber wood were investigated to determine suitability of the wood fibres for some industrial utilization. The fibre lengths were sampled according to main effects such as plantations effects ...

  15. Microwave pre-heating of natural rubber using a rectangular wave guide (MODE: TE10

    Directory of Open Access Journals (Sweden)

    Doo-ngam, N.


    Full Text Available This paper presents an application of microwave radiation for pre-heating of natural rubbercompounding with various sulphur contents. The natural rubber-compounding was pre-heated by microwave radiation using a rectangular wave guide system (MODE: TE10 operating at frequency of 2.45 GHz in which the power can vary from 0 to 1500 W. In the present work, the influence of power input, sample thickness, and sulphur content were examined after applying microwave radiation to the rubber samples. Results are discussed regarding the thermal properties, 3-D network, dielectric properties and chemical structures. From the result, firstly, it was found that microwave radiation can be applied to pre-heating natural rubber-compounding before the vulcanization process. Secondly, microwave radiation was very useful for pre-heating natural rubber-compounding that has a thickness greater than 5mm. Thirdly, crosslinking in natural rubber-compounding may occurs after pre-heating by microwave radiation though Fourier Transform Infrared Spectroscopy(FTIR. Finally, there a little effect of sulphur content on temperature profiles after applying microwave radiation to the natural rubber-compounding. Moreover, natural rubber-compounding without carbon black showed a lower heat absorption compared with natural rubbercompounding filled carbon black. This is due to the difference in dielectric loss factor. This preliminary result will be useful information in terms of microwave radiation for pre-heating natural rubber-compounding and rubber processing in industry.

  16. Down-Regulation of Small Rubber Particle Protein Expression Affects Integrity of Rubber Particles and Rubber Content in Taraxacum brevicorniculatum (United States)

    Hillebrand, Andrea; Post, Janina J.; Wurbs, David; Wahler, Daniela; Lenders, Malte; Krzyzanek, Vladislav; Prüfer, Dirk; Gronover, Christian Schulze


    The biosynthesis of rubber is thought to take place on the surface of rubber particles in laticifers, highly specialized cells that are present in more than 40 plant families. The small rubber particle protein (SRPP) has been supposed to be involved in rubber biosynthesis, and recently five SRPPs (TbSRPP1–5) were identified in the rubber-producing dandelion species Taraxacum brevicorniculatum. Here, we demonstrate by immunogold labeling that TbSRPPs are localized to rubber particles, and that rubber particles mainly consist of TbSRPP3, 4 and 5 as shown by high-resolution two-dimensional gel electrophoresis and mass spectrometric analysis. We also carried out an RNA-interference approach in transgenic plants to address the function of TbSRPPs in rubber biosynthesis as well as rubber particle morphology and stability. TbSRPP-RNAi transgenic T. brevicorniculatum plants showed a 40–50% reduction in the dry rubber content, but neither the rubber weight average molecular mass nor the polydispersity of the rubber were affected. Although no phenotypical differences to wild-type particles could be observed in vivo, rubber particles from the TbSRPP-RNAi transgenic lines were less stable and tend to rapidly aggregate in expelling latex after wounding of laticifers. Our results prove that TbSRPPs are very crucial for rubber production in T. brevicorniculatum, probably by contributing to a most favourable and stable rubber particle architecture for efficient rubber biosynthesis and eventually storage. PMID:22911861

  17. Down-regulation of small rubber particle protein expression affects integrity of rubber particles and rubber content in Taraxacum brevicorniculatum.

    Directory of Open Access Journals (Sweden)

    Andrea Hillebrand

    Full Text Available The biosynthesis of rubber is thought to take place on the surface of rubber particles in laticifers, highly specialized cells that are present in more than 40 plant families. The small rubber particle protein (SRPP has been supposed to be involved in rubber biosynthesis, and recently five SRPPs (TbSRPP1-5 were identified in the rubber-producing dandelion species Taraxacum brevicorniculatum. Here, we demonstrate by immunogold labeling that TbSRPPs are localized to rubber particles, and that rubber particles mainly consist of TbSRPP3, 4 and 5 as shown by high-resolution two-dimensional gel electrophoresis and mass spectrometric analysis. We also carried out an RNA-interference approach in transgenic plants to address the function of TbSRPPs in rubber biosynthesis as well as rubber particle morphology and stability. TbSRPP-RNAi transgenic T. brevicorniculatum plants showed a 40-50% reduction in the dry rubber content, but neither the rubber weight average molecular mass nor the polydispersity of the rubber were affected. Although no phenotypical differences to wild-type particles could be observed in vivo, rubber particles from the TbSRPP-RNAi transgenic lines were less stable and tend to rapidly aggregate in expelling latex after wounding of laticifers. Our results prove that TbSRPPs are very crucial for rubber production in T. brevicorniculatum, probably by contributing to a most favourable and stable rubber particle architecture for efficient rubber biosynthesis and eventually storage.

  18. Robotically enhanced rubber hand illusion. (United States)

    Arata, Jumpei; Hattori, Masashi; Ichikawa, Shohei; Sakaguchi, Masamichi


    The rubber hand illusion is a well-known multisensory illusion. In brief, watching a rubber hand being stroked by a paintbrush while one's own unseen hand is synchronously stroked causes the rubber hand to be attributed to one's own body and to "feel like it's my hand." The rubber hand illusion is thought to be triggered by the synchronized tactile stimulation of both the subject's hand and the fake hand. To extend the conventional rubber hand illusion, we introduce robotic technology in the form of a master-slave telemanipulator. The developed one degree-of-freedom master-slave system consists of an exoskeleton master equipped with an optical encoder that is worn on the subject's index finger and a motor-actuated index finger on the rubber hand, which allows the subject to perform unilateral telemanipulation. The moving rubber hand illusion has been studied by several researchers in the past with mechanically connected rigs between the subject's body and the fake limb. The robotic instruments let us investigate the moving rubber hand illusion with less constraints, thus behaving closer to the classic rubber hand illusion. In addition, the temporal delay between the body and the fake limb can be precisely manipulated. The experimental results revealed that the robotic instruments significantly enhance the rubber hand illusion. The time delay is significantly correlated with the effect of the multisensory illusion, and the effect significantly decreased at time delays over 100 ms. These findings can potentially contribute to the investigations of neural mechanisms in the field of neuroscience and of master-slave systems in the field of robotics.

  19. Pushing the Limits: The Pattern and Dynamics of Rubber Monoculture Expansion in Xishuangbanna, SW China.

    Directory of Open Access Journals (Sweden)

    Huafang Chen

    Full Text Available The rapidly growing car industry in China has led to an equally rapid expansion of monoculture rubber in many regions of South East Asia. Xishuangbanna, the second largest rubber planting area in China, located in the Indo-Burma biodiversity hotspot, supplies about 37% of the domestic natural rubber production. There, high income possibilities from rubber drive a dramatic expansion of monoculture plantations which poses a threat to natural forests. For the first time we mapped rubber plantations in and outside protected areas and their net present value for the years 1988, 2002 (Landsat, 30 m resolution and 2010 (RapidEye, 5 m resolution. The purpose of our study was to better understand the pattern and dynamics of the expansion of rubber plantations in Xishuangbanna, as well as its economic prospects and conservation impacts. We found that 1 the area of rubber plantations was 4.5% of the total area of Xishuangbanna in 1988, 9.9% in 2002, and 22.2% in 2010; 2 rubber monoculture expanded to higher elevations and onto steeper slopes between 1988 and 2010; 3 the proportion of rubber plantations with medium economic potential dropped from 57% between 1988 and 2002 to 47% in 2010, while the proportion of plantations with lower economic potential had increased from 30% to 40%; and 4 nearly 10% of the total area of nature reserves within Xishuangbanna has been converted to rubber monoculture by 2010. On the basis of our findings, we conclude that the rapid expansion of rubber plantations into higher elevations, steeper terrain, and into nature reserves (where most of the remaining forests of Xishuangbanna are located poses a serious threat to biodiversity and environmental services while not producing the expected economic returns. Therefore, it is essential that local governments develop long-term land use strategies for balancing economic benefits with environmental sustainability, as well as for assisting farmers with the selection of land suitable

  20. Nano-reinforcement of tire rubbers: silica-technology for natural rubber : exploring the infuence of non-rubber constituents on the natural rubber-silica system

    NARCIS (Netherlands)

    Sarkawi, S.S.


    Natural rubber is a renewable resource material with outstanding properties which offers significant advantages over its counterparts, the fossil-resource synthetic rubbers. In fact, a natural rubber tree is an efficient carbon dioxide sequester. Since natural rubber is a natural product, it is

  1. Solubility Study of Curatives in Various Rubbers

    NARCIS (Netherlands)

    Guo, R.; Talma, Auke; Datta, Rabin; Dierkes, Wilma K.; Noordermeer, Jacobus W.M.


    The previous works on solubility of curatives in rubbers were mainly carried out in natural rubber. Not too much information available on dissimilar rubbers and this is important because most of the compounds today are blends of dissimilar rubbers. Although solubility can be expected to certain

  2. Industrialization


    Blundel, Richard


    Industrialization, the historical development that saw cheesemaking transformed from a largely craft-based or artisanal activity, often located on a dairy farm, to a production process that, for the most part, takes place in large ‘cheese factories’ or creameries [See ARTISANAL]. The principal features of modern industrialized cheesemaking, which set it apart from traditional approaches include: high production volumes; sourcing of milk from multiple dairy herds; pasteurization and re-balanci...

  3. Industry

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, Lenny; Roy, Joyashree; Delhotal, K. Casey; Harnisch, Jochen; Matsuhashi, Ryuji; Price, Lynn; Tanaka, Kanako; Worrell, Ernst; Yamba, Francis; Fengqi, Zhou; de la Rue du Can, Stephane; Gielen, Dolf; Joosen, Suzanne; Konar, Manaswita; Matysek, Anna; Miner, Reid; Okazaki, Teruo; Sanders, Johan; Sheinbaum Parado, Claudia


    This chapter addresses past, ongoing, and short (to 2010) and medium-term (to 2030) future actions that can be taken to mitigate GHG emissions from the manufacturing and process industries. Globally, and in most countries, CO{sub 2} accounts for more than 90% of CO{sub 2}-eq GHG emissions from the industrial sector (Price et al., 2006; US EPA, 2006b). These CO{sub 2} emissions arise from three sources: (1) the use of fossil fuels for energy, either directly by industry for heat and power generation or indirectly in the generation of purchased electricity and steam; (2) non-energy uses of fossil fuels in chemical processing and metal smelting; and (3) non-fossil fuel sources, for example cement and lime manufacture. Industrial processes also emit other GHGs, e.g.: (1) Nitrous oxide (N{sub 2}O) is emitted as a byproduct of adipic acid, nitric acid and caprolactam production; (2) HFC-23 is emitted as a byproduct of HCFC-22 production, a refrigerant, and also used in fluoroplastics manufacture; (3) Perfluorocarbons (PFCs) are emitted as byproducts of aluminium smelting and in semiconductor manufacture; (4) Sulphur hexafluoride (SF{sub 6}) is emitted in the manufacture, use and, decommissioning of gas insulated electrical switchgear, during the production of flat screen panels and semiconductors, from magnesium die casting and other industrial applications; (5) Methane (CH{sub 4}) is emitted as a byproduct of some chemical processes; and (6) CH{sub 4} and N{sub 2}O can be emitted by food industry waste streams. Many GHG emission mitigation options have been developed for the industrial sector. They fall into three categories: operating procedures, sector-wide technologies and process-specific technologies. A sampling of these options is discussed in Sections 7.2-7.4. The short- and medium-term potential for and cost of all classes of options are discussed in Section 7.5, barriers to the application of these options are addressed in Section 7.6 and the implication of


    Directory of Open Access Journals (Sweden)

    Ionuţ Ovidiu TOMA


    Full Text Available The use of rubber from discarded car tires as an alternative to natural aggregates in concrete may help preventing the complete depletion of natural resources and work towards a sustainable future. Moreover it can significantly reduce the environmental footprint of the construction industry. The assessment of the dynamic properties of a material are very important from the point of view of the energy dissipation capability of the investigated material. This can be determined from the dynamic modulus of elasticity, damping and the loss coefficients of the material. The paper presents the results obtained during an experimental program aimed at assessing the dynamic characteristics of plain and rubberized concrete containing rubber crumbs from discarded car tires. The theoretical background and the investigation methodology are presented with particular application to cylindrical concrete specimens.


    Directory of Open Access Journals (Sweden)

    Rosa Cristina Cecche Lintz


    Full Text Available The production of waste by the tire industry has been a growing problem, indicating the need for its reuse. More than thirty million tires are discharged per year in Brazil, where regulation for the environment states that for each four new tires, five unusable ones must be adequately disposed by manufacturers and importers. Paving consumes an extremely large quantity of materials, which can be the source of rational application of waste and rejected materials. Research shows that tire rubber can be added to asphalt, which increases its durability and improves pavement quality and safety conditions by absorbing the rubber elastic properties, and also be used for architectural applications, among others. This study deals with the addition of rubber fibers from tire crushing in concrete for roadway pavements in order to provide proper indication about the alternative material disposal through an evaluation of the mechanical behavior of the modified concrete. Different concrete mixes were produced, within which, part of fine aggregates were substituted by tire rubber and mechanical experiment tests were performed, which show that, due to great resistance losses, the disposal of this alternative material in concrete should be considered for light traffic pavements, with the addition of rubber ranging up to 10% in mass.

  6. Flashover Characteristics of Silicone Rubber Sheets under Various Environmental Conditions

    Directory of Open Access Journals (Sweden)



    Full Text Available Silicone rubber insulators are replacing the conventional ceramic and porcelain insulators rapidly in power transmission and distribution industry. Very limited field knowledge is available about the performance of silicone rubber insulators in polluted and contaminated environments and therefore need further investigation. A comprehensive analysis of silicone rubber sheets (intended for coating outdoor insulators was carried out in this paper based on experimental results. The main performance parameters analyzed were arc inception voltage and flashover voltage. Dependence of these parameters on equivalent salt deposit density (ESDD, non-soluble salt deposit density (NSDD, relative humidity, ambient temperature, fog rate, dry band formation, dry band location and number of dry bands were investigated extensively. Insulator orientation and its effect on performance were also studied. The authors believe that this paper will provide a comprehensive knowledge about the flashover characteristics of silicone rubber insulators under humid, contaminated and dry band conditions. These results could be used in the selection and design of silicone rubber insulators for polluted environments.


    Directory of Open Access Journals (Sweden)

    Rosa Cristina Cecche Lintz


    Full Text Available The production of waste by the tire industry has been a growing problem, indicating the need for its reuse. More than thirty million tires are discharged per year in Brazil, where regulation for the environment states that for each four new tires, five unusable ones must be adequately disposed by manufacturers and importers. Paving consumes an extremely large quantity of materials, which can be the source of rational application of waste and rejected materials. Research shows that tire rubber can be added to asphalt, which increases its durability and improves pavement quality and safety conditions by absorbing the rubber elastic properties, and also be used for architectural applications, among others. This study deals with the addition of rubber fibers from tire crushing in concrete for roadway pavements in order to provide proper indication about the alternative material disposal through an evaluation of the mechanical behavior of the modified concrete. Different concrete mixes were produced, within which, part of fine aggregates were substituted by tire rubber and mechanical experiment tests were performed, which show that, due to great resistance losses, the disposal of this alternative material in concrete should be considered for light traffic pavements, with the addition of rubber ranging up to 10% in mass.

  8. British Columbia log export policy: historical review and analysis. (United States)

    Craig W. Shinn


    Log exports have been restricted in British Columbia for over 100 years. The intent of the restriction is to use the timber in British Columbia to encourage development of forest industry, employment, and well-being in the Province. Logs have been exempted from the within-Province manufacturing rule at various times, in varying amounts, for different reasons, and by...

  9. On the Fresh/Hardened Properties of Cement Composites Incorporating Rubber Particles from Recycled Tires

    Directory of Open Access Journals (Sweden)

    Alessandra Fiore


    Full Text Available This study investigates the ameliorative effects on some properties of cement-based materials which can be obtained by incorporating rubber particles as part of the fine aggregates. The aim is to find out optimal cement composite/mortar mixtures, containing recycled-tyre rubber particles, suitable for specific engineering applications. Different percentages of rubber particles, from 0% to 75%, were used and, for each percentage, the suitable amount of sand was investigated in order to achieve the best fresh/hardened performances. In particular the following characteristics were examined: density, compressive strength, modulus of elasticity, shrinkage, weight loss, flexural behaviour, thermal conductivity, rapid freezing and thawing durability, and chloride permeability. The experimental results were compared with the ones of cement composite specimens without rubber aggregates. Test results show that the proposed rubberized mortar mixes are particularly suitable for some industrial and architectural applications, such as under-rail bearings, road constructions, paving slabs, false facades, and stone backing.

  10. Identification of a Taraxacum brevicorniculatum rubber elongation factor protein that is localized on rubber particles and promotes rubber biosynthesis. (United States)

    Laibach, Natalie; Hillebrand, Andrea; Twyman, Richard M; Prüfer, Dirk; Schulze Gronover, Christian


    Two protein families required for rubber biosynthesis in Taraxacum brevicorniculatum have recently been characterized, namely the cis-prenyltransferases (TbCPTs) and the small rubber particle proteins (TbSRPPs). The latter were shown to be the most abundant proteins on rubber particles, where rubber biosynthesis takes place. Here we identified a protein designated T. brevicorniculatum rubber elongation factor (TbREF) by using mass spectrometry to analyze rubber particle proteins. TbREF is homologous to the TbSRPPs but has a molecular mass that is atypical for the family. The promoter was shown to be active in laticifers, and the protein itself was localized on the rubber particle surface. In TbREF-silenced plants generated by RNA interference, the rubber content was significantly reduced, correlating with lower TbCPT protein levels and less TbCPT activity in the latex. However, the molecular mass of the rubber was not affected by TbREF silencing. The colloidal stability of rubber particles isolated from TbREF-silenced plants was also unchanged. This was not surprising because TbREF depletion did not affect the abundance of TbSRPPs, which are required for rubber particle stability. Our findings suggest that TbREF is an important component of the rubber biosynthesis machinery in T. brevicorniculatum, and may play a role in rubber particle biogenesis and influence rubber production. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

  11. Rubber extrusion theory and development

    National Research Council Canada - National Science Library

    Crowther, B. G


    ... Adjustable Profile Dies Extruder Screw Design 21 22 23 24 24 Acknowledgement Additional References ' 25 25 References from the Rapra Abstracts Database 27 Subject Index 95 1Rubber Extrusion Theo...

  12. An assessment of rubber dam usage amongst specialists in paediatric dentistry practising within the UK. (United States)

    Soldani, Francesca; Foley, Jennifer


    Rubber dam is recommended by the British Society of Paediatric Dentistry (BSPD) for various restorative and endodontic procedures. To date, there has been no report of actual usage of rubber dam within the speciality of paediatric dentistry. The aim of this study was to assess the usage of rubber dam amongst paediatric dentistry specialists within the UK. A postal questionnaire was distributed to all practitioners registered on the UK General Dental Council's 2004 specialist list in paediatric dentistry. Data were available for 162 questionnaires (a 75% response rate), and of these, 85% of respondents worked in the National Health Service (NHS), 4% were private practitioners and the remainder had a mixed NHS/private practice. Regarding the benefits of rubber dam, 65% and 52% of respondents quoted patient safety and moisture control, respectively. Perceived difficulties of dam usage were lack of patient cooperation and the non-necessity for a particular treatment, as quoted in 64% and 36% of the completed questionnaires, respectively. The most common modes of isolation for anterior and posterior teeth were Dry Dam(R) (58%), and clamp and dam (80%), respectively. Current BSPD guidelines recommend rubber dam usage for many restorative procedures; however, it would appear that there is wide variability in the application, as well as under-use, of rubber dam.


    Directory of Open Access Journals (Sweden)

    Andrzej Plewa


    Full Text Available With the development of the automotive industry the disposal of used tires is constantly growing problem. Storage of waste rubber is associated with a very long period of decomposition of rubber in the natural conditions. Simultaneously new technologies are developed every year, which in the future may significantly promote recycling of this type of materials. The crumb rubbery modification of the road bitumen is the one of the environmentally safe solutions of rubbery decomposition. Improvement of resistance of the crumb rubbery modification of the road asphalt mixtures is the very important ecological aspect of the future. The article presents the results of research on the fatigue life resistance of asphalt concretes AC16P and AC22P with asphalt-rubber binders. The above analyses have been based on the results of tests of fatigue life of mineral-rubber-asphalt mixes determined by the method of prismatic four-point bending (4PB-PR. Mineral-rubber -asphalt mixes have been diversified according to the amount of the additive of rubber fines in asphalt-rubber binder. On the basis of the test results have been proven improvements functional properties mineral-rubber-asphalt mixes compared with mineral-asphalt mixes with unmodified asphalt.

  14. New understanding of microstructure formation of the rubber phase in thermoplastic vulcanizates (TPV). (United States)

    Wu, Hanguang; Tian, Ming; Zhang, Liqun; Tian, Hongchi; Wu, Youping; Ning, Nanying


    The breakup of the rubber phase in an ethylene-propylene-diene monomer (EPDM)/polypropylene (PP) blend at the early stage of dynamic vulcanization is similar to that in an unvulcanized EPDM/PP blend because of the low crosslink density of the EPDM phase. In this work, the minimum size of the rubber phase in the unvulcanized EPDM/PP blend was first calculated by using the critical breakup law of viscoelastic droplets in a matrix. The calculated results showed that the minimum size of the rubber phase in the unvulcanized blend was in the nanometer scale (25-46 nm), not the micrometer scale as reported in many works. Meanwhile, the actual size of the rubber phase in the thermoplastic vulcanizate (TPV) at both the early stage and the final stage of dynamic vulcanization was observed by using peak force tapping atomic force microscopy (PF-AFM). The results indicated that the EPDM phase indeed broke up into nanoparticles at the early stage of dynamic vulcanization, in good agreement with the calculated results. More interestingly, we first revealed that the micrometer-sized rubber particles commonly observed in TPV were actually the agglomerates of rubber nanoparticles with diameters between 40 and 60 nm. The mechanism for the formation of rubber nanoparticles and their agglomerates during dynamic vulcanization was then discussed. Our work provides guidance to control the microstructure of the rubber phase in TPV to prepare high performance TPV products for a wide range of applications in the automobile and electronic industries.

  15. Effects of Running Shoes with Abrasion Resistant Rubber Sole on the Exercise Capacity of the Human Body

    Directory of Open Access Journals (Sweden)

    Bo Wang


    Full Text Available With the development of industrialization, rubber has been gradually used in the manufacture of sports equipment for its favourable properties. This study involved the addition of C5 petroleum resin into brominated isobutylene-isoprene rubber (BIIR and butadiene rubber (BR while manufacturing the sole of running shoes. The effects of running shoes with abrasion resistant rubber sole on the exercise capacity of the human body were investigated by analysing the skid resistance and abrasion resistance of the running shoes, and conducting biomechanical study on naked feet and feet wearing the shoes. The results demonstrated that the rubber sole had favourable slip resistance property and mechanical properties such as stretching, abrasion resistance, and hardness. Compared to naked feet, the peak pressure intensity of the whole step of feet wearing the newly developed shoes, was significantly lower than that of feet wearing ordinary shoes. In the future, rubber can bring more comfortable experience because of its favourable properties.

  16. Properties of Concrete Containing Scrap-Tire Rubber

    National Research Council Canada - National Science Library

    Mazyad Al-Fadhli; Jasem Alhumoud


    ...–rubber particles as aggregate in concrete is investigated in this study. Tire–rubber particles composed of tire chips, crumb rubber, and a combination of tire chips and crumb rubber, were used to replace mineral aggregates in concrete...

  17. Rubber mixing process and its relationship with bound rubber and crosslink density (United States)

    Hasan, A.; Rochmadi; Sulistyo, H.; Honggokusumo, S.


    This research studied the relationship between bound rubber and crosslink density based on rubber mixing process. Bound rubber was obtained after natural rubber was masticated and mixed with rubber chemicals and filler while crosslink density was collected after rubber compound was vulcanized. Four methods are used and each method refers to four ways of incorporating carbon black during mixing. The first method, after rubber was masticated for 5 minutes, the addition of rubber chemicals and filler was done simultaneously. Rubber was masticated for 1 minute and continued mixing of rubber chemicals and filler where mixing was different from first method. This was the second method. The third method was the same as the second method but the filler used N 660 while in the second method N 330. The last method is not the same as the first and second, the rubber is only masticated for 3 minutes and then mixed with filler and followed by rubber chemicals sequentially. The results showed that bound rubber and crosslink density were influenced by mixing and mastication process. Bound rubber dropped and crosslink density was relatively stable in the first three mixing methods for increasing carbon black at the beginning of the mixing process. Bound rubber and crosslink density stated opposite results in the fourth mixing method. The higher the bound rubber the lower the crosslink density. Without regard to mixing methods, there is a non-linear relationship between bound rubber formation and crosslink density determination

  18. Rubber: new allergens and preventive measures. (United States)

    Crepy, Marie-Noëlle


    Natural rubber latex (NRL) and rubber accelerators are well-known causes of occupational skin diseases. The latest epidemiological data on rubber allergy show that rubber additives are still among the allergens most strongly associated with occupational contact dermatitis, however, a decrease in NRL allergy has been confirmed. A review of recent publications on rubber allergens based on the Pubmed database is presented. New glove manufacturing processes have been developed, such as low-protein natural rubber gloves, vulcanisation accelerator-free gloves, or specific-purpose gloves containing antimicrobial agents or moisturisers. Several websites provide information on allergens found in gloves and/or glove choice according to occupation.

  19. Exposure to mutagenic airborne particulate in a rubber manufacturing plant. (United States)

    Fracasso, M E; Franceschetti, P; Mossini, E; Tieghi, S; Perbellini, L; Romeo, L


    Epidemiological studies conducted in the 1980s revealed that people working in the rubber manufacturing industry had an increased risk of cancer. Even now, workers employed in rubber processing are still at risk despite the measures adopted to improve their working conditions. The aim of the study was to evaluate the presence of a genotoxic risk in a rubber industry and to verify whether or not it was possible to locate the most dangerous position among the different rubber-working processes. The mutagenic activity of airborne particulate was evaluated in samples collected in the mixing department of a rubber manufacturing plant. Ambient air samples were taken over 3-h period in two stable positions near the mixing (Banbury mixer) and calendering areas. Personal air samples were taken over 2-h period during a normal workday from five workers employed in different rubber processing operations (mixing, weighing, calendering, compounding and extruding). The mutagenic activity of the air samples was determined by plate incorporation assay using Salmonella typhimurium strains (TA 98, TA 98NR, TA 100, YG 1021) with and without metabolic activation. Polycyclic aromatic hydrocarbon (PAH) concentrations were determined by high-performance liquid chromatography (HPLC); the presence of other presumable contaminants were carried out by gas chromatography-mass spectrometry (GC-MS). The results showed substantial direct and indirect frameshift mutagenicity in both ambient and personal samples. No mutagenic activity was present in S. typhimurium TA 100, except in the personal sample from a worker employed on the Banbury mixer. HPLC analysis revealed very low concentrations of PAHs. GC-MS analysis showed the presence of compounds such as azulene derivative, 1,2-dihydro-2,2,4-trimethylquinoline, N-methyl N-phenylbenzenamine, diphenylamine, bis(2-ethylhexyl)phthalate and bis(methyl-propyl)phthalate. We conclude that the high levels of mutagenic activity in ambiental and personal

  20. Four Centuries of British Economic Growth

    DEFF Research Database (Denmark)

    Madsen, Jakob B.; Ang, James B.; Banerjee, Rajabrata


    of two competing second-generation endogenous growth models to account for the British growth experience. The results suggest that innovative activity was an important force in shaping the Industrial Revolution and that the British growth experience is consistent with Schumpeterian growth theory.......Using long historical data for Britain over the period 1620–2006, this paper seeks to explain the importance of innovative activity, population growth and other factors in inducing the transition from the Malthusian trap to the post-Malthusian growth regime. Furthermore, the paper tests the ability...

  1. National Innovation System and Disruptive Innovations in Synthetic Rubber and Tire Technology

    Directory of Open Access Journals (Sweden)

    Ray R. Gehani


    Full Text Available The current models of National Innovation Systems (NIS are based on interactions and learning across three institutions: government, university and industry. This empirical study of the evolution of innovations in rubber and tire technologies such as the collaborative innovative suppliers (of raw materials and human capital and disruptive rival innovators to the traditional tri-helical model of National Innovation System. This was empirically examined for the evolution of rubber and tire technology and the rise and decline of its innovative region: the Rubber Capital of the World in Akron, Ohio.

  2. Targeted testing with diethylthiourea often reveals clinically relevant allergic contact dermatitis caused by neoprene rubber

    DEFF Research Database (Denmark)

    Dall, Anne B-H; Andersen, Klaus Ejner; Mortz, Charlotte G


    Background. Diethylthiourea is widely used in the rubber industry, particularly in neoprene rubber, and may cause allergic contact dermatitis. However, as thiourea allergens are not part of the European baseline series, the diagnosis of allergic contact dermatitis caused by thiourea compounds......, and positive reactions were found in 15% (13/88). Thus, 15% (37/239) had positive patch test reactions to diethylthiourea, all with current clinical relevance and all strong. Conclusion. Clinical suspicion of neoprene rubber allergy and subsequent aimed patch testing with diethylthiourea give a high yield...

  3. Replacement value of rubber seed ( Hevea brasiliensis ) meal for ...

    African Journals Online (AJOL)

    Rubber seed meal (RSM) contains about 28.63% CP but also high in CF (20%). Rubber seed cake was extruded after the extraction of rubber seed oil from the Rubber Seed oil processing Department of Rubber Research Institute of Nigeria, Benin-City. The rubber seed cake was then milled to produce RSM. Soya bean ...

  4. Eco-Certification of Natural Rubber: Demand, Supply, and Potential Implications of Private Global Environmental Governance


    Kennedy, Sean


    In recent years, concern over the environmental impacts of natural rubber culti- vation has generated considerable interest in eco-certification, a form of private environ- mental regulation designed to encourage more sustainable land-use practices. This paper explores the emergence and potential sovereignty implications of this approach to envi- ronmental control with an emphasis on the natural rubber industry. I argue that although eco-certification is advocated as a form of networked gover...

  5. Thermodynamic description of performance characteristics pneumatic elastic elements with rubber-cord envelopes (United States)

    Korneev, S. A.; Korneev, V. S.; Adonin, V. A.


    The thermodynamic computational method of pneumatic elements with rubber-cord envelopes geometrical and power characteristics of the different designs used in a buffer systems and the industrial facilities vibro protection, including, petrochemical and oil and gas production is explained. The record of rubber-cord envelope resilient deformation allowed to obtain the valid data having important applied meaning. Temperature effect is reflected in the received defining ratios.

  6. Nylon fabric reinforced natural rubber compound (United States)

    Kamal, Mazlina Mustafa; Ismail, Ismaliza


    Rubber fabric coated is a unique rubber-textile composite, in which technical textile acts as reinforcing material and strength providing material. In rubber textile composite, rubber to fabric adhesion plays the most critical role for determining assembly process and ultimate strength of product. A vulcanisable adhesive for rubber to fabric fabrication of composite material was developed which compatible with rubber as well as fabric. Evaluation of bonding system with respect to peel strength, shear adhesion strength and weave pattern of fabrics were the major determining criteria for selection and optimization of fabric for rubber hose application. Thus adhesive Cohedure with characteristics of high adhesive strength in Natural Rubber Polyester Fabric compound has been developed.

  7. Advances in rubber/halloysite nanotubes nanocomposites. (United States)

    Jia, Zhixin; Guo, Baochun; Jia, Demin


    The research advances in rubber/halloysite nanotubes (rubber/HNTs) nanocomposites are reviewed. HNTs are environmentally-friendly natural nanomaterials, which could be used to prepare the rubber-based nanocomposites with high performance and low cost. Unmodified HNTs could be adopted to prepare the rubber/HNTs composites with improved mechanical properties, however, the rubber/HNTs nanocomposites with fine morphology and excellent properties were chiefly prepared with various modifiers by in situ mixing method. A series of rubber/HNTs nanocomposites containing several rubbers (SBR, NR, xSBR, NBR, PU) and different modifiers (ENR, RH, Si69, SA, MAA, ILs) have been investigated. The results showed that all the rubber/HNTs nanocomposites achieved strong interfacial interaction via interfacial covalent bonds, hydrogen bonds or multiple interactions, realized significantly improved dispersion of HNTs at nanoscale and exhibited excellent mechanical performances and other properties.

  8. 75 FR 57980 - Polychloroprene Rubber From Japan (United States)


    ... From the Federal Register Online via the Government Publishing Office INTERNATIONAL TRADE COMMISSION Polychloroprene Rubber From Japan AGENCY: United States International Trade Commission. ACTION... whether revocation of the antidumping duty finding on polychloroprene rubber from Japan would be likely to...

  9. Electrospinning of PVC with natural rubber

    Energy Technology Data Exchange (ETDEWEB)

    Othman, Muhammad Hariz; Abdullah, Ibrahim [Department of Chemistry, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Mohamed, Mahathir [Radiation Processing Technology Division (BTS), Malaysian Nuclear Agency, Bangi, 43000, Kajang (Malaysia)


    Polyvinyl chloride (PVC) was mixed with natural rubbers which are liquid natural rubber (LNR), liquid epoxidised natural rubber (LENR) and liquid epoxidised natural rubber acrylate (LENRA) for a preparation of a fine non-woven fiber’s mat. PVC and each natural rubbers(PVC:LENR, PVC:LNR and PVC:LENRA) were mixed based on ratio of 70:30. Electrospinning method was used to prepare the fiber. The results show that the spinnable concentration of PVC/ natural rubber/THF solution is 16 wt%. The morphology, diameter, structure and degradation temperature of electrospun fibers were investigated by scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). SEM photos showed that the morphology and diameter of the fibers were mainly affected by the addition of natural rubber. TGA results suggested that PVC electrospun fiber has higher degradation temperature than those electrospun fibers that contain natural rubber.

  10. Natural rubber producing plants: An overview | Venkatachalam ...

    African Journals Online (AJOL)

    ... Hevea and also other natural rubber producing species for alternative source of latex production in the near future. Keywords: Alternative rubber sources, biotechnology, breeding, Hevea brasiliensis, Parthenium argentatum, Taraxacum koksaghyz, Ficus bengalensis, Lactuca serriola. African Journal of Biotechnology Vol.

  11. Evaluation of polybutadiene rubbers using FTIR spectra

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, L.N.; Schimidt, F., E-mail: [Instituto Federal de Educacao, Ciencia e Tecnologia de Goias (IFG), Goiania, GO (Brazil); Antonio, P.L.; Caldas, L.V.E. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Vieira, S.L. [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Instituto de Fisica


    Radiation dosimetry for medical and industrial purposes has increasingly evolved over the last few decades with the introduction of various new detectors. Depending on the properties exhibited for radiation dosimetry, some detectors present their applications in a specific area. From a physics point of view, an ideal dosimeter should be able to measure absorbed dose. In this work, synthetic materials based on polybutadiene rubbers (PBR) were proposed as a new class of radiation detectors. The influence of radiation dose on their properties has been investigated for application in radiation dosimetry. The rubber samples were exposed to absorbed doses from 10 Gy up to 250 Gy, using a {sup 60}Co Gamma Cell-220 system. Their responses were carried out with a Fourier Transform Infrared (FTIR) Spectrometer to investigate the presence of absorbance peaks. The results suggested the existence of a relationship between the absorbed doses and the absorbance peaks associated with stretching (1300-1200 cm{sup -1}), deformation (1450-1340 cm{sup -1}) and vibration (1500-1400 cm{sup -1}) processes in the material. (author)

  12. Application of gamma irradiation for incorporation of rubber powder in the formulations of acrylonitrile-butadiene rubber (NBR)

    Energy Technology Data Exchange (ETDEWEB)

    Kiyan, Ludmila Y.P.; Parra, Duclerc Fernandes, E-mail: [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Quimica e Meio Ambiente (CQMA)


    Full text: Polymeric materials do not decompose easily, disposal of waste polymers is a major environmental problem of global character. Recycling is an economical alternative and environmentally recommended for polymers consumed and discarded by society. As regards the rubber in object, its natural decomposition is much slower due to their highly crosslinked, in three-dimensional networks, structures which makes it an infusible and insoluble material. Moreover, these three dimensional structures entails several problems for their recovery and reprocessing. The aim of this paper was to study the behavior of NBR rubber recycle. It was used rubber powder from industry. The powder was irradiated in master-batch composition and used directly in classical formulations for rubber vulcanization. The master-batch processed was irradiated at doses of 50, 100 and 150kGy in {sup 60}Co source at 5 kGy s{sup -1} rate, at room temperature. Gamma radiation created active sites during devulcanization that promoted further integration of the rubber powder in formulations for commercial use. The processes were compared and their products were characterized by analytical methods of the physical properties such as tensile strength and elongation. The greatest change in the properties of polymeric materials by exposure to ionizing radiation resulted mainly of two main reactions occurring in the polymer molecule: chains scission (degradation) and crosslinking. Although these two processes occur simultaneously in all the polymers, the predominance of one or other effect depends mainly of the chemical structure of each polymer, and the irradiation conditions. In the results was observed the behavior of nitrile rubber under different doses and radiation improvement of the mechanical properties. (author)

  13. Enhancing natural rubber ( Hevea brasiliensis production through ...

    African Journals Online (AJOL)

    The study investigated extension activities in natural rubber production in South West Zone of Nigeria. Fifty rubber farmers randomly selected from five communities in the rubber belt sub-zone were sampled. A structured interview schedule was used in collecting data from the respondents.Statistical analysis was ...

  14. 75 FR 38119 - Polychloroprene Rubber From Japan (United States)


    ... COMMISSION Polychloroprene Rubber From Japan AGENCY: United States International Trade Commission. ACTION: Institution of a five-year review concerning the antidumping duty finding on polychloroprene rubber from Japan... antidumping duty finding on polychloroprene rubber from Japan would be likely to lead to continuation or...

  15. Calamus deerratus fibre reinforced natural rubber vulcanizates ...

    African Journals Online (AJOL)

    This research study investigates the potentials of Calamus deerratus fibre (CDF) as a reinforcing filler in natural rubber, Standard Nigerian Rubber (SNR10) vulcanizates. The Calamus deerratus was cut, dried, pulverized, characterized and incorporated into the natural rubber compounds and the effects on the cure ...

  16. Morphology, Tensile Strength and Oil Resistance of Gum Rubber Sheets Prepared from Lignin Modified Natural Rubber

    Directory of Open Access Journals (Sweden)

    Asrul M.


    Full Text Available The paper describes the preparation of lignin filled natural rubber latex composite and its subsequent use to obtain lignin modified rubber. Two types of lignin i.e.: rubber wood and commercial alkali lignin were used as rubber filler. Gum rubber sheets were prepared from the lignin modified rubber and their properties were compared to Standard Malaysian Rubber (SMR 20 and a type of rubber obtained from the coagulation of high ammonia latex. Rubber morphology was investigated using Scanning Electron Microscope on the cross-sectional area of cryo-fractured samples. Oil resistance of the rubber sheets was determined by measuring the mass change before and after ASTM IRM 903 oil immersion, while the tensile strengths were determined according to ASTM D412 standard. Low values of tensile strength obtained for the commercial alkali lignin modified rubber sheet relative to the rest of the rubber samples was attributed to poor lignin dispersion. This occurrence was substantiated by the SEM analysis of cryo-fractured samples where crazes and inhomogeneity was observed. Nonetheless, both lignin modified rubbers exhibited higher level of oil resistance compared to SMR 20. This is due to the nature of lignin as a hydrophilic component and its presence in the rubber matrix complicates the oil diffusion process into rubber.

  17. Chronocentrism and British criminology. (United States)

    Rock, Paul


    Criminologists display a largely unexamined propensity to ignore writings that are more than fifteen or so years old, with evident consequences for the public presentation and validation of expert knowledge. A citation study was combined with detailed observations from British criminologists to ascertain quite how that disavowal of the past was accomplished.

  18. Through the Technology Lens: The Expansion of Rubber and its Implications in Montane Mainland Southeast Asia

    Directory of Open Access Journals (Sweden)

    Jefferson Fox


    Full Text Available Natural latex from the rubber tree (Hevea brasiliensis is a hot commodity, with consumption increasing worldwide at an average rate of 5.8% per year since 1900. The vast majority of the world′s rubber supply has historically come from the wet-humid tropics of Southeast Asia, but researchers in China have successfully developed new hybrids that grow well in areas with cooler temperatures and a distinct dry season. Today, investors are promoting rubber plantations in non-traditional rubber growing areas of Laos, Cambodia, Myanmar, northeast Thailand, and northwest Vietnam. By critically assessing the impacts of this expansion of rubber and clarifying the relationship between tools and technologies, the paper suggests that the widespread adoption of rubber as a technology leads to loss of natural and agricultural biodiversity; greater use of surface and groundwater supplies; increased use of pesticides, fertilisers, and other chemicals; higher exposure to market booms and busts for smallholders and investors; and for some farmers, the loss of their land to industrial plantations on which they may become labourers. The paper argues that if state authorities recognise the double-edged nature of rubber as a technology, they can act to try to limit its damaging effects through polices that recognise secure tenure and encourage small-scale, diversified agroforestry systems.

  19. Provincial land use planning in British Columbia

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, W. [British Columbia Ministry of Finance, Victoria, BC (Canada). Land Use Coordination Office


    The efforts being made to include Aboriginal communities in land use planning in British Columbia are discussed. British Columbia is in the midst of historic changes with respect to land and resource allocation, use and management. Historic trends in land use allocation and management are contrasted with land use planning and resource management of today. The impact of provincial government moves to double park space within the province, and the Protected Areas Strategy initiative will have on the natural gas and petroleum industry is discussed. New efforts being made to include First Nations directly in land use planning discussions in ways that do not prejudice treaty negotiations, are reviewed. Creation of a new Oil and Gas Commission in the Fort St. John area, is cited as the most recent example of the interconnections between First Nations communities and other public and industry stakeholders in land use planning in the province.

  20. Identification of an exposure risk to heavy metals from pharmaceutical-grade rubber stoppers. (United States)

    Li, Xianghui; Qian, Pingping


    Exposure to low concentrations of heavy metals and metalloids represents a well-documented risk to animal and human health. However, current standards (European Pharmacopeia [EP], United States Pharmacopoeia [USP], International Organization for Standardization [ISO], YBB concerned with rubber closures) only require testing for Zn in pharmaceutical-grade rubber stoppers and then using only pure water as a solvent. We extracted and quantified heavy metals and trace elements from pharmaceutical-grade rubber stoppers under conditions that might occur during the preparation of drugs. Pure water, saline, 10% glucose, 3% acetic acid (w/v), 0.1 mol/L hydrochloric acid, and diethylenetriaminepentaacetic acid (4 mg/mL, 0.4 mg/mL, and 0.04 mg/mL) were used as extraction agents. We quantified the extracted arsenic, lead, antimony, iron, magnesium, aluminum, and zinc using inductively coupled plasma mass spectrometry. The concentration of extracted metals varied depending on the different extraction solutions used and between the different rubber stopper manufacturers. Rubber stoppers are ubiquitously used in the pharmaceutical industry for the storage and preparation of drugs. Extraction of heavy metals during the manufacturing and preparation of drugs represents a significant risk, suggesting a need for industry standards to focus on heavy metal migration from rubber stoppers. Copyright © 2016. Published by Elsevier B.V.

  1. Degradation of non-vulcanized natural rubber - renewable resource for fine chemicals used in polymer synthesis

    Directory of Open Access Journals (Sweden)

    Alexander Fainleib


    Full Text Available In the current scenario, there is growing interest in the products of degradation of rubber (natural and synthetic for specific applications in different industry sectors, whose benefits in replacing conventionally used products are mainly related to sustainability. Since the degradation products of rubber can be used in different areas, several research groups may have the interest aroused by these products, but are not familiar with the aspects related to the chemical behavior of rubber. This review aims to bring together the key information in the published literature on the degradation of natural rubber, emphasizing metatheses reactions, oxidative damage and splitting of the double bond, in order to serve as a reference source for researchers from different fields interested in obtaining such kind of products. The structures and properties as well as additional chemical transformations resulting in oligomers of isoprene, functionalised oligomers and polymers based on both are also described.


    Directory of Open Access Journals (Sweden)

    Jochen Streb


    Full Text Available I investigated the effect of government demand on firms’ innovation activities comparing the German and American synthetic rubber industries before, during and after World War II. I obtained three main results. 1. Because of the low price of natural rubber, price and sales guarantees were needed to motivate firms to produce the synthetic rubber BUNA S. 2. Facing fixed prices I.G. Farben improved their efficiency more than the American firms working under cost plus contracts. 3. The patent sharing agreement of the American synthetic rubber program caused firms to hold back advanced synthetic rubber inventions.

  3. In-depth proteome analysis of the rubber particle of Hevea brasiliensis (para rubber tree). (United States)

    Dai, Longjun; Kang, Guijuan; Li, Yu; Nie, Zhiyi; Duan, Cuifang; Zeng, Rizhong


    The rubber particle is a special organelle in which natural rubber is synthesised and stored in the laticifers of Hevea brasiliensis. To better understand the biological functions of rubber particles and to identify the candidate rubber biosynthesis-related proteins, a comprehensive proteome analysis was performed on H. brasiliensis rubber particles using shotgun tandem mass spectrometry profiling approaches-resulting in a thorough report on the rubber particle proteins. A total of 186 rubber particle proteins were identified, with a range in relative molecular mass of 3.9-194.2 kDa and in isoelectric point values of 4.0-11.2. The rubber particle proteins were analysed for gene ontology and could be categorised into eight major groups according to their functions: including rubber biosynthesis, stress- or defence-related responses, protein processing and folding, signal transduction and cellular transport. In addition to well-known rubber biosynthesis-related proteins such as rubber elongation factor (REF), small rubber particle protein (SRPP) and cis-prenyl transferase (CPT), many proteins were firstly identified to be on the rubber particles, including cyclophilin, phospholipase D, cytochrome P450, small GTP-binding protein, clathrin, eukaryotic translation initiation factor, annexin, ABC transporter, translationally controlled tumour protein, ubiquitin-conjugating enzymes, and several homologues of REF, SRPP and CPT. A procedure of multiple reaction monitoring was established for further protein validation. This comprehensive proteome data of rubber particles would facilitate investigation into molecular mechanisms of biogenesis, self-homeostasis and rubber biosynthesis of the rubber particle, and might serve as valuable biomarkers in molecular breeding studies of H. brasiliensis and other alternative rubber-producing species.

  4. The Industrial Revolution: A Misnomer. (United States)

    Cameron, Rondo


    Argues that the British industrial revolution was in no sense inevitable and scarcely deserves the term "revolution." Examined are the characteristics which the British shared with other Europeans and ways in which they were distinctive that enabled them to become the first industrial nation. (RM)

  5. Comparative proteome analysis of rubber latex serum from pathogenic fungi tolerant and susceptible rubber tree (Hevea brasiliensis). (United States)

    Havanapan, Phattara-Orn; Bourchookarn, Apichai; Ketterman, Albert J; Krittanai, Chartchai


    Many cultivated rubber trees (Hevea brasiliensis) are invaded by various Phytophthora species fungi, especially in tropical regions which result in crop yield losses. Comparative proteome analysis coupled with liquid chromatography electrospray/ionization (LC-ESI) mass spectrometry identification was employed to investigate the relative abundance of defense related proteins in Phytophthora sp. susceptible (RRIM600) and tolerant (BPM24) clones of rubber tree. Proteome maps of non-rubber constituent of these two model clones show similar protein counts, although some proteins show significant alterations in their abundance. Most of the differentially abundant proteins found in the serum of BPM24 illustrate the accumulation of defense related proteins that participate in plant defense mechanisms such as beta-1,3-glucanase, chitinase, and lectin. SDS-PAGE and 2-D Western blot analysis showed greater level of accumulation of beta-1,3-glucanase and chitinase in latex serum of BPM24 when compared to RRIM600. A functional study of these two enzymes showed that BPM24 serum had greater beta-1,3-glucanase and chitinase activities than that of RRIM600. These up-regulated proteins are constitutively expressed and would serve to protect the rubber tree BPM24 from any fungal invader. The information obtained from this work is valuable for understanding of defense mechanisms and plantation improvement of H. brasiliensis. Non-rubber constituents (latex serum) have almost no value and are treated as waste in the rubber agricultural industry. However, the serum of natural rubber latex contains biochemical substances. The comparative proteomics analysis of latex serum between tolerant and susceptible clones reveals that the tolerant BPM24 clone contained a high abundance of several classes of fungal pathogen-responsive proteins, such as glucanase and chitinase. Moreover, other proteins identified highlighted the accumulation of defensive-associated proteins participating in plant

  6. Para rubber seed oil: new promising unconventional oil for cosmetics. (United States)

    Lourith, Nattaya; Kanlayavattanakul, Mayuree; Sucontphunt, Apirada; Ondee, Thunnicha


    Para rubber seed was macerated in petroleum ether and n-hexane, individually, for 30 min. The extraction was additionally performed by reflux and soxhlet for 6 h with the same solvent and proportion. Soxhlet extraction by petroleum ether afforded the greatest extractive yield (22.90 ± 0.92%). Although antioxidant activity by means of 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assay was insignificantly differed in soxhleted (8.90 ± 1.15%) and refluxed (9.02 ± 0.71%) by n-hexane, soxhlet extraction by n-hexane was significantly (p cosmetic raw material. Therefore, Para rubber seed oil is highlighted as the promising ecological ingredient appraisal for cosmetics. Transforming of the seed that is by-product of the important industrial crop of Thailand into cosmetics is encouraged accordingly.

  7. Thermomechanical characterisation of cellular rubber (United States)

    Seibert, H.; Scheffer, T.; Diebels, S.


    This contribution discusses an experimental possibility to characterise a cellular rubber in terms of the influence of multiaxiality, rate dependency under environmental temperature and its behaviour under hydrostatic pressure. In this context, a mixed open and closed cell rubber based on an ethylene propylene diene monomer is investigated exemplarily. The present article intends to give a general idea of the characterisation method and the considerable effects of this special type of material. The main focus lies on the experimental procedure and the used testing devices in combination with the analysis methods such as true three-dimensional digital image correlation. The structural compressibility is taken into account by an approach for a material model using the Theory of Porous Media with additional temperature dependence.

  8. Constructing better roads with asphalt rubber

    Directory of Open Access Journals (Sweden)

    Pais Jorge C.


    Full Text Available Brazilians mixtures containing asphalt rubber were evaluated by mechanical laboratory tests. A conventional mixture with asphalt CAP-50/70 was produced as a mixture control. With the aim of compare the Brazilians mixtures performance, a Portuguese asphalt rubber mixture was tested as well. The testing set involved the determination of the mechanical properties, fatigue and permanent deformation, of asphalt rubber produced by wet process through two different systems: continuous blend and terminal blend. The asphalt rubber morphology was evaluated in order to determine the compatibility of the systems. The asphalt rubber mixtures exhibit good resistance to permanent deformation and prolonged fatigue life in relation to mixture control. Therefore it is concluded that the application of asphalt rubber alters the characteristics of asphalt mixture in a very beneficial way.

  9. Adding crumb rubber into exterior wall materials. (United States)

    Zhu, Han; Thong-On, Norasit; Zhang, Xiong


    In Arizona US, most houses are built with walls covered by stuccos/coatings/mortars. This paper presents an explorative investigation of adding crumb rubber into stuccos/coatings/mortars. A series of experiments are conducted to examine the thermal and mechanical performance of the crumb rubber mixes. The results show that, the mixes with crumb rubber do exhibit more desirable performances like being high in crack-resistance and thermal insulation, and low in thermal expansion/contraction. The drawback for the crumb rubber mixes is the reduction in compressive strength, but which can be compensated by other means. As a site experiment, an area of 100 square-feet of crumb rubber coatings for two mix designs is sprayed on a tire-adobe wall. After being sprayed more than 14 months, the coatings apparently are in good condition. Significance of this study is that this practice, if accepted, will yield improved products that consume large quantities of crumb rubber.

  10. Prehistoric polymers: rubber processing in ancient mesoamerica (United States)

    Hosler; Burkett; Tarkanian


    Ancient Mesoamerican peoples harvested latex from Castilla elastica, processed it using liquid extracted from Ipomoea alba (a species of morning glory vine), and fashioned rubber balls, hollow rubber figurines, and other rubber artifacts from the resulting material. Chemical and mechanical analyses of the latex and of the processed rubber indicate that the enhanced elastic behavior of the rubber relative to the unprocessed latex is due to purification of the polymer component and to an increase in the strength and number of interchain interactions that are induced by organic compounds present in I. alba. These ancient peoples' control over the properties of latex and processed rubber gave rise to the Mesoamerican ball game, a central ritual element in all ancient Mesoamerican societies.

  11. Identification of Natural Rubber and Characterization of Rubber Biosynthetic Activity in Fig Tree1 (United States)

    Kang, Hunseung; Kang, Min Young; Han, Kyung-Hwan


    Natural rubber was extracted from the fig tree (Ficus carica) cultivated in Korea as part of a survey of rubber producing plants. Fourier transform infrared and 13C nuclear magnetic resonance analysis of samples prepared by successive extraction with acetone and benzene confirmed that the benzene-soluble residues are natural rubber, cis-1,4-polyisoprene. The rubber content in the latex of fig tree was about 4%, whereas the rubber content in the bark, leaf, and fruit was 0.3%, 0.1%, and 0.1%, respectively. Gel-permeation chromatography revealed that the molecular size of the natural rubber from fig tree is about 190 kD. Similar to rubber tree (Hevea brasiliensis) and guayule (Parthenium argentatum Gray), rubber biosynthesis in fig tree is tightly associated with rubber particles. The rubber transferase in rubber particles exhibited a higher affinity for farnesyl pyrophosphate than for isopentenyl pyrophosphate, with apparent Km values of 2.8 and 228 μm, respectively. Examination of latex serum from fig tree by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed major proteins of 25 and 48 kD in size, and several proteins with molecular mass below 20 and above 100 kD. Partial N-terminal amino acid sequencing and immunochemical analyses revealed that the 25- and 48-kD proteins were novel and not related to any other suggested rubber transferases. The effect of EDTA and Mg2+ ion on in vitro rubber biosynthesis in fig tree and rubber tree suggested that divalent metal ion present in the latex serum is an important factor in determining the different rubber biosynthetic activities in fig tree and rubber tree. PMID:10889262

  12. Chemistry of rubber processing and disposal. (United States)

    Bebb, R L


    The major chemical changes during the processing of rubber occur with the breakdown in mastication and during vulcanization of the molded tire. There is little chemical change during the compounding, calendering, extrusion, and molding steps. Reclaiming is the process of converting scrap rubber into an unsaturated, processible product that can be vulcanized with sulfur. Pyrolysis of scrap rubber yields a complex mixture of liquids, gas, and residue in varying ratios dependent on the nature of the scrap and the conditions of pyrolysis.

  13. Brittle-tough transition in nylon-rubber blends: effect of rubber concentration and particle size

    NARCIS (Netherlands)

    Borggreve, R.J.M.; Gaymans, R.J.; Schuijer, J.; Ingen Housz, J.F.


    Blends of nylon-6 and EPDM-rubber were prepared with various rubber contents (0–20 wt%) and particle sizes (0.3–1.6 μm). The effects of rubber concentration and particle size on the tensile modulus, torsion modulus, yield stress and notched impact strength of the blends were studied. Blend

  14. Effect of non-rubber constituents on Guayule and Hevea rubber intrinsic properties (United States)

    To meet the increasing demand for natural rubber (NR), currently sourced from the tropical rubber tree Hevea brasiliensis, and address price volatility and steadily increasing labor costs, alternate rubber-producing species are in commercial development. One of these, guayule (Parthenium argentatum)...



  16. Design of the Nonlinear Pin Rubber Forming Equipment Integrating the Functions of Extruding, Dewatering, Drying & Expanding

    Directory of Open Access Journals (Sweden)

    Yuefeng Yuan


    Full Text Available The top priority of car-tire suppliers is to improve wetland grip force of the using tires, reduce the rolling resistance and the rolling noise of tires. It is urgent for the tire industry to research and develop high-performance tires to solve the above problems. They must use the high- performance synthetic rubber and auxiliary rubber to develop the most advanced manufacturing technologies and equipment. Silica, a kind of important tire auxiliary rubber, can significantly reduce the rolling resistance of tires, improve the grip force and properties resistant to ice, wetness or slippery of tires. In this paper, based on the conventional tire rubber forming technologies of extrusion, dewatering, drying and expanding, a study is made on the conical screw, the dewatering barrel, the drying barrel, the pin layout scheme, the expanding die head, cutter and the control system. The nonlinear pin rubber forming equipment integrating the functions of extrusion, dewatering, drying and expanding is designed and applied to tire auxiliary rubber forming. The experiment shows that the forming device can realize the one-step forming, with high forming efficiency, low cost and less labor.

  17. Utilization of Liquid Smoke from Oil Palm Empty Fruit Bunches on Raw Rubber Processing

    Directory of Open Access Journals (Sweden)

    Hidayati Hidayati


    Full Text Available Research utilization of liquid smoke from oil palm empty fruit bunches of raw rubber has been made to utilize solid waste from industrial processing of oil palm empty fruit bunches of oil palm so that it becomes economically valuable products. This research has been done by pyrolysis of oil palm empty fruit bunches at a temperature of 400oC for 5, 6, 7 and 8 hours. The results show that the pyrolysis liquid smoke oil palm empty fruit bunches for 8 hours give a high concentration of phenol and acetic acid, respectively 5% and 0.454%. Liquid smoke that has been obtained is used as a coagulant in raw rubber plantation crops of the people residing in the village of Ambawang, Kubu Raya District, West Kalimantan. Results of treatment of liquid smoke on raw rubber  show that the rubber products that have been frozen and dried are superior in terms of color, smell and drying time compared with the treatment of formic acid and water battery which has been added so far on raw rubber by the local rubber farmers.

  18. Effect of synthesized ZnO nanoparticles on thermal conductivity and mechanical properties of natural rubber (United States)

    Suntako, R.


    Zinc oxide (ZnO) is widely used in rubber industry as a cure activator for rubber vulcanization. In this work, comparison of cure characteristic, mechanical properties, thermal conductivity and volume swell testing in oil no.1 and oil no.3 between natural rubber (NR) filled synthesized ZnO nanoparticles (sZnO) by precipitation method and NR filled conventional ZnO (cZnO). The particle size of sZnO is 41.50 nm and specific area of 27.92 m2/g, the particle size of cZnO is 312.92 nm and specific surface area of 1.35 m2/g. It has been found that NR filled sZnO not only improves rubber mechanical properties, volume swell testing but also improves thermal conductivity and better than NR filled cZnO. Thermal conductivity of NR filled sZnO increases by 10.34%, 12.90% and 20.00%, respectively when compared with NR filled cZnO in same loading content (various concentrations of ZnO at 5, 8 and 10 parts per hundred parts of rubber). This is due to small particle size and large specific surface area of sZnO which lead to an increase in crosslinking in rubber chain and enhance heat transfer performance.

  19. War of the British Worlds

    DEFF Research Database (Denmark)

    Mercau, Ezequiel


    The 1982 Falklands War was shrouded in symbolism, bringing to the fore divergent conceptions of Britishness, kinship, and belonging. This article casts light on the persistent purchase of the idea of Greater Britain long after the end of empire, addressing a case that would normally be deemed...... outside its spatial and temporal boundaries. By highlighting the inherent contradictions of this transnational bond, the South Atlantic conflict had a profound effect on an underexposed British community with a lingering attachment to a “British world”: the Anglo-Argentines. As they found themselves...... different “British worlds” against each other....

  20. Molecular phylogeny of Rigidoporus microporus isolates associated with white rot disease of rubber trees (Hevea brasiliensis). (United States)

    Oghenekaro, Abbot O; Miettinen, Otto; Omorusi, Victor I; Evueh, Grace A; Farid, Mohd A; Gazis, Romina; Asiegbu, Fred O


    Rigidoporus microporus (Polyporales, Basidiomycota) syn. Rigidoporus lignosus is the most destructive root pathogen of rubber plantations distributed in tropical and sub-tropical regions. Our primary objective was to characterize Nigerian isolates from rubber tree and compare them with other West African, Southeast Asian and American isolates. To characterize the 20 isolates from Nigeria, we used sequence data of the nuclear ribosomal DNA ITS and LSU, β-tubulin and translation elongation factor 1-α (tef1) gene sequences. Altogether, 40 isolates of R. microporus were included in the analyses. Isolates from Africa, Asia and South/Central America formed three distinctive clades corresponding to at least three species. No phylogeographic pattern was detected among R. microporus collected from West and Central African rubber plantations suggesting continuous gene flow among these populations. Our molecular phylogenetic analysis suggests the presence of two distinctive species associated with the white rot disease. Phylogenetic analyses placed R. microporus in the Hymenochaetales in the vicinity of Oxyporus. This is the first study to characterize R. microporus isolates from Nigeria through molecular phylogenetic techniques, and also the first to compare isolates from rubber plantations in Africa and Asia. Copyright © 2014 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  1. Prediction of heat generation in rubber or rubber-metal springs

    Directory of Open Access Journals (Sweden)

    Banić Milan S.


    Full Text Available The temperature of rubber or rubber-metal springs increases under cyclic loading, due to hysteresis losses and low rubber thermal conductivity. Hysteresis losses correspond to energy dissipation from the rubber, which is primarily converted into heat. This well-known phenomenon, called heat build-up, is the primary reason for rubber aging. Increase in temperature within the rubber compound leads to degradation of its physical and chemical properties, increase in stiffness and loss of damping capability. This paper presents a novel procedure of heat generation prediction in rubber or rubber-metal springs. The procedure encompasses the prediction of hysteresis loss, i. e. dissipated energy within the rubber, by finite element analysis and application of a modern visco-plastic rubber constitutive model. The obtained dissipated energy was used as an input for transient thermal analysis. Verification of the proposed procedure was performed by comparison of simulation results with experimentally obtained data during the dynamic loading of the rubber specimen. The proposed procedure is highly computationally efficient and it enables time integration, which can be problematic in coupled mechanical thermal analysis. [Projekat Ministarstva nauke Republike Srbije, br. TR35005: Research and Development of New Generation of Wind Turbines of High Energy Efficiency

  2. Effect of Recycled Rubber Particles and Silica on Tensile and Tear Properties of Natural Rubber Composites

    Directory of Open Access Journals (Sweden)



    Full Text Available Application of scrap rubber and worn out tires in natural rubber compounds has been studied. The scrap rubber can, however, be recycled and compounded with natural rubber and thus can be generated as a rubber composite. In this work, recycled rubber particles (RRP were prepared using pulverization process. Then, RRP was blended with natural rubber and silica compounds, and it was synthesized by two- roll mill and hydraulic press at specified operating conditions. The samples ranging from 0 to 40 phr of RRP loaded with silica were used as constant filler. The mechanical properties and morphological analysis were carried out. The results showed that tensile strength and elongation at break gradually decreased with increasing RRP loading in natural rubber and silica compounds. Tensile modulus went down at 10 phr of RRP and then showed an increasing trend. Hardness increased up to 30 phr of RRP and tear strength increased up to 20 phr of RRP. A comparative study was also carried out with virgin natural rubber vulcanizates. The incorporation of RRP and silica up to 20 phr in natural rubber did not lower the performance of rubber articles. Morphological studies revealed that better filler dispersion, interfacial adhesion, and cross link density could increase the tensile and tear strengths.DOI:

  3. Conference Proceedings: Photography and Britishness

    Directory of Open Access Journals (Sweden)

    Sean Willcock


    Full Text Available The video-recordings presented here were made at the conference Photography and Britishness, held at the Yale Center for British Art on November 4 – 5, 2016. The conference was the result of a collaboration between the Yale Center for British Art, New Haven, the Paul Mellon Centre for Studies in British Art, London, and the Huntington Library, Art Collections, and Botanical Gardens in San Marino—three research institutions that have a converging interest in British art. The conference sought to investigate the various ways in which notions of “Britishness” have been communicated, inflected, and contested through the photographic image. It was not a conference about the history of photography in Britain, or about British photography. Rather, it sought to consider the nature of the relationship between photography and Britishness: the notion that photography can capture images of Britishness, at the same time that our sense of what Britishness constitutes is produced by the photographic image. A key question for the conference was whether Britishness can have a photographic referent—or whether it is itself an effect of representation. Speakers at the conference approached these questions from a wide range of perspectives and focusing on a diverse number of photographic materials—from family albums and studio portraits to advertisements, reportage, and aerial photography—which demonstrated the complexities and instabilities not only of the term Britishness, but also of the medium of photography. The conference was opened with an introduction by John Tagg. The videos included here are presented in the order they were delivered.

  4. Unraveling the Mystery of Natural Rubber Biosynthesis (United States)

    Natural rubber (NR) is primarily obtained from Hevea brasiliensis, commonly known as the Brazilian rubber tree. As this species contains little genetic variation, it is susceptible to pathogen-based eradication. Consequently, it is imperative that a biomimetic pathway for NR production be developed....

  5. Biorefinery of proteins from rubber plantation residues

    NARCIS (Netherlands)

    Widyarani, R.


    Biorefinery of rubber tree side streams could add economic value and income for farmers, who already grow the trees for latex production. The objective of this research was to design a process for the recovery of proteinaceous fractions from rubber tree. The aimed applications were expected to be

  6. Roughness Perception during the Rubber Hand Illusion (United States)

    Schutz-Bosbach, Simone; Tausche, Peggy; Weiss, Carmen


    Watching a rubber hand being stroked by a paintbrush while feeling identical stroking of one's own occluded hand can create a compelling illusion that the seen hand becomes part of one's own body. It has been suggested that this so-called rubber hand illusion (RHI) does not simply reflect a bottom-up multisensory integration process but that the…

  7. Amino acid modifiers in guayule rubber compounds (United States)

    Tire producers are increasingly interested in biobased materials, including rubber but also as compounding chemicals. An alternative natural rubber for tire use is produced by guayule, a woody desert shrub native to North America. Alternative compounding chemicals include naturally-occurring amino a...


    African Journals Online (AJOL)


    Nov 3, 2012 ... Abstract. The objective of this study was to produce activated carbon from rubber seed pericarp and to evaluate its performance with commercial activated carbon in the treatment of abattoir wastewater as well as its potential in the adsorption of iron (III) ions from aqueous solution. The rubber seed pericarp ...


    Mesrobian, R.B.; Ballantine, D.S.; Metz, D.J.


    A method of vulcanizing rubber latex by exposing a mixture containing rubber latex and from about 15 to about 21.3 wt% of 2,5-dichlorostyrene to about 1.1 megarads of gamma radiation while maintaining the temperature of the mixture at a temperature ranging between from about 56 to about 59 deg C is described. (AEC)

  10. Patients' attitudes to rubber dam. (United States)

    Stewardson, D A; McHugh, E S


    The aims of this study were to record patients' views of their experience of RD use in an objective manner, and to evaluate the influence of some personal and clinical factors on patients' opinion. A questionnaire was designed which was then distributed to patients receiving dental treatment under RD by (a) final-year dental students at Birmingham Dental School, and (b) general dental practitioners. Patients completed the confidential questionnaire anonymously after treatment, outside the treatment room. After 100 correctly completed forms were collected from group (a) and 106 from group (b), data were entered into a database and subsequently analyzed using SPSS. Analyses were confined to simple cross-tabulations of the patients' responses and potential associated factors, with chi-square analysis and appropriate follow-up comparisons wherever necessary. In both groups, the majority of patients said they would prefer RD to be used at their next appointment, and most had a positive opinion of the experience. No statistically significant association between age, sex, procedure, application time or duration of use and preference for rubber dam was found. Prolonged RD use showed some association with a negative opinion of the experience of RD. Compared with the dentists, students took longer to apply rubber dam and it was in place for longer. Fewer student patients preferred RD next time, and were less positive about its use than the dentists' patients. Further evidence is presented that (i) Patients generally are not averse to RD. (ii) Placement of rubber dam does not take long. (iii) Operator experience improves patient compliance.

  11. Photoinduced orientation in natural rubber (United States)

    de Souza, Nara C.; Cavalheri, Adriana S.; Brito, Jackeline B.; Job, Aldo E.; Oliveira, Osvaldo N.; Giacometti, José A.; Silva, Josmary R.


    Azobenzene molecules and their derivatives have been widely investigated for their potential applications in optical and electrooptical devices. We have prepared a new guest-host system from natural rubber (NR) impregnated with azobenzene derivative Sudan Red B (SRB). The effects of stretching and immersion time on photoinduced orientation were investigated by birefringence signal measurements. We have found that the molecular orientation increase when the samples are stretched and decrease with the increase of immersion time. The first behavior was explained by using the random coil model and the latter was attributed to increase of the aggregation of SRB into NR matrix.

  12. Coal Producer's Rubber Waste Processing Development (United States)

    Makarevich, Evgeniya; Papin, Andrey; Nevedrov, Alexander; Cherkasova, Tatyana; Ignatova, Alla


    A large amount of rubber-containing waste, the bulk of which are worn automobile tires and conveyor belts, is produced at coal mining and coal processing enterprises using automobile tires, conveyor belts, etc. The volume of waste generated increases every year and reaches enormous proportions. The methods for processing rubber waste can be divided into three categories: grinding, pyrolysis (high and low temperature), and decomposition by means of chemical solvents. One of the known techniques of processing the worn-out tires is their regeneration, aimed at producing the new rubber substitute used in the production of rubber goods. However, the number of worn tires used for the production of regenerate does not exceed 20% of their total quantity. The new method for processing rubber waste through the pyrolysis process is considered in this article. Experimental data on the upgrading of the carbon residue of pyrolysis by the methods of heavy media separation, magnetic and vibroseparation, and thermal processing are presented.

  13. Occupational exposure to rubber vulcanization products during repair of rubber conveyor belts in a brown coal mine. (United States)

    Gromiec, Jan P; Wesołowski, Wiktor; Brzeźnicki, Sławomir; Wróblewska-Jakubowska, Krystyna; Kucharska, Małgorzata


    Several hundred chemical compounds were found in workroom environments in the rubber industry, but most of the published exposure data relate to the production of tyres; information from the "non-tyre" sections are very limited, if any. This study was carried out to identify chemical substances and measure their air concentrations in the repair shop of a brown coal mine in which damaged rubber conveyor belts were repaired. GC-MS and HPLC analysis of stationary air samples resulted in identification of aliphatic and aromatic hydrocarbons to C12, PAHs, alcohols, phenols, ketones, heterocyclic nitrogen and sulfur compounds. Quantitative evaluation of occupational exposure included determination of organic compound vapours collected on charcoal (GC-MSD), polycyclic aromatic hydrocarbons (HPLC), N-nitrosoamines and other amines (GC-NPD) and DNPH derivatives of aldehydes (HPLC) in the breathing zone of workers representing all job titles. The concentrations of investigated compounds were very low. Carcinogenic substances: N-nitrosoamines, benzene, PAHs were not present in workroom air in concentrations exceeding limits of detection of the analytical methods being applied; concentrations of methylisobutylketone, tetrachloroethylene, naphtha, aromatic hydrocarbons, phthalates and aldehydes were much lower than the respective occupational exposure limit values. The results indicate much lower exposure than that reported in the production of tyres and other fabricated rubber products.

  14. Science and technology of rubber reclamation with special attention to NR based waste latex products

    NARCIS (Netherlands)

    Rajan, V.V.; Dierkes, Wilma K.; Joseph, R.; Noordermeer, Jacobus W.M.


    A comprehensive overview of reclamation of cured rubber with special emphasis on latex reclamation is depicted in this paper. The latex industry has expanded over the years to meet the world demands for gloves, condoms, latex thread, etc. Due to the strict specifications for the products and the

  15. Natural rubber latex: determination and interpretation of flow curves

    Directory of Open Access Journals (Sweden)

    Harrison Lourenço Corrêa


    Full Text Available AbstractAs consumers become more demanding, the importance grows of guaranteeing the quality of products. The employment of reliable testing techniques that assure the origin and characteristics of the inputs used by industry is a key factor in this respect. In the rubber processing industry, the most commonly used characterization tests include determination of the total solids and dry rubber content, mechanical stability, odor, color and presence of volatile compounds, among others. For the most part, these tests are sufficient for the latex transformation industry. However, in situations where there is a need to know the behavior of latex in reaction to the mechanical forces of machines (mixers, pumps, etc., other tests must be used. Rheological tests to determine viscoelastic data by means of plotting flow curves combined with the application of theoretical models can provide important details for characterization of different types of latex. This article presents the protocol employed by the Rheology and Image Laboratory of Rio de Janeiro State University (UERJ for the rheological study of Brazilian latex. The samples analyzed came from the state of São Paulo.

  16. The Effect of Rubber Mixing Process on The Curing Characteristics of Natural Rubber

    Directory of Open Access Journals (Sweden)

    Abu Hasan


    Full Text Available This research is aimed at studying the relationship between rubber mixing processes and curing characteristics of natural rubber. The curing characteristic analysis was carried out through a natural rubber formula having been masticated and mixed, followed by curing. As many as four mastication methods were finely applied; each respected four sequences of rubber mixing process. In the first method, rubber was masticated for 5 minutes and then rubber chemicals and carbon black N 330 were  simultaneously added. In the second and the third methods, rubber was masticated for 1 minute and then carbon blacks and rubber chemicals were also simultaneously added but using different type of fillers. In the fourth method, rubber was masticated for 3 minutes and then rubber chemicals and carbon black were subsequently added. The additions of rubber chemicals and carbon blacks to the masticated rubber were distinguished by the sequence and time allocated for each mixing process. The carbon blacks were added in two stages by which 10 phr was added first and the remaining 40 phr was added later along with oil. In another method, ratios of the carbon blacks addition (as done in the first  and the second stages were 20:30, 30:20, and 40:10. The examination results showed that rubber mixing process gave an impact on the changes of curing characteristics. They were much affected by the method of carbon black addition. The mixing temperature also had an effect on both curing time and curing rate in which the higher the mixing temperature, the lower the curing time and curing rate. Vulcanization temperature also affected the curing time and curing rate in which the higher the vulcanization temperature, the lower the curing time and the higher the curing rate. Lastly, particle size of carbon black also gave an impact on the curing time and curing rate in which the smaller the particle size, the lower the curing time and the higher the curing rate.

  17. Minimum Variance Estimation of Yield Parameters of Rubber Tree ...

    African Journals Online (AJOL)

    Although growth and yield data are available in rubber plantations in Nigeria for aggregate rubber production planning, existing models poorly estimate the yield per rubber tree for the incoming year. Kalman lter, a exible statistical estimator, is used to combine the inexact prediction of the rubber production with an equally ...

  18. 30 CFR 77.606-1 - Rubber gloves; minimum requirements. (United States)


    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Rubber gloves; minimum requirements. 77.606-1... COAL MINES Trailing Cables § 77.606-1 Rubber gloves; minimum requirements. (a) Rubber gloves (lineman's... be used and tested in accordance with the provisions of §§ 77.704-6 through 77.704-8. (b) Rubber...

  19. Ratings for the Mercantile Marine: The Roles of Charity, the State and Industry in the Pre-Service Education and Training of Ratings for the British Merchant Navy, 1879-1939. (United States)

    Kennerley, Alston


    Considers the development of education and training arrangements of ratings in merchant ships. Explores the changing shipping industry and its manning, the training ship movement, the agitation concerning trained seafarers and developments prior to 1917, and the creation of the shipping industry's own ratings training system and its place in…

  20. 1970 British Cohort Study

    Directory of Open Access Journals (Sweden)

    Matt Brown


    Full Text Available The 1970 British Cohort Study (BCS70 is one of Britain’s world famous national longitudinal birth cohort studies, three of which are run by the Centre for Longitudinal Studies at the Institute of Education, University of London.  BCS70 follows the lives of more than 17,000 people born in England, Scotland and Wales in a single week of 1970. Over the course of cohort members lives, the BCS70 has collected information on health, physical, educational and social development, and economic circumstances among other factors. Since the birth survey in 1970, there have been nine ‘sweeps’ of all cohort members at ages 5, 10, 16, 26, 30, 34, 38 and most recently at 42. Data has been collected from a number of different sources (the midwife present at birth, parents of the cohort members, head and class teachers, school health service personnel and the cohort members themselves. The data has been collected in a variety of ways including via paper and electronic questionnaires, clinical records, medical examinations, physical measurements, tests of ability, educational assessments and diaries. The majority of BCS70 survey data can be accessed by bona fide researchers through the UK Data Service at the University of Essex.

  1. Butterfly valve of all rubber lining type

    Energy Technology Data Exchange (ETDEWEB)

    Shimada, Shosaku; Nakatsuma, Sumiya (Kubota Ltd., Osaka (Japan)); Sasaki, Iwao; Aoki, Naoshi


    The valves used for the circulating water pipes for condensers in nuclear and thermal power stations have become large with the increase of power output, and their specifications have become strict. The materials for the valves change from cast iron to steel plate construction. To cope with sea water corrosion, rubber lining has been applied to the internal surfaces of valve boxes, and the build-up welding of stainless steel has been made on the edges of valves. However, recently it is desired to develop butterfly valves, of which the whole valve disks are lined with hard rubber. For the purpose of confirming the performance of large bore valves, a 2600 mm bore butterfly valve of all rubber lining type was used, and the opening and closing test of 1100 times was carried out by applying thermal cycle and pressure difference and using artifical sea water. Also the bending test of hard rubber lining was performed with test pieces. Thus, it was confirmed that the butterfly valves of all rubber lining type have the performance exceeding that of the valves with build-up welding. The course of development of the valves of all rubber lining type, the construction and the items of confirmation by tests of these valves, and the tests of the valve and the hard rubber lining described above are reported.

  2. Hyundai plans rubber unit despite overcapacity

    Energy Technology Data Exchange (ETDEWEB)

    Hyoungjin Kim


    Despite the oversupply of synthetic rubber in South Korea, the government has granted approval to Hyundai Petrochemical (Seoul) to build the country's second synthetic rubber unit, to be located alongside its petrochemical complex at Daesan. The plant is due for startup during second-half 1995, when the local market is expected to be in better balance. Hyundai will use Goodyear Tire Rubber technology for the plant, which will have annual capacities for 40,000 m.t. of polybutadiene rubber (BR), 30,000 m.t. of styrene butadiene rubber (SBR) and 12,000 m.t. of nitrile rubber (NBR). Styrene and butadiene requirements will be met from Hyundai's own production at Daesan. The current local producer of synthetic rubber is Korea Kumho Petrochemicals (Seoul), which has annual capacities for 150,000 m.t. of SBR, 95,000 m.t. of BR, and 10,000 m.t. of NBR. Korean SBR demand is about 141,000 m.t./year but is expected to increase to 161,000 m.t./year by 1996 and reach 194,000 m.t./year by the end of the decade.


    Directory of Open Access Journals (Sweden)

    Duncan Philip Connors


    Full Text Available The history of British industrial decline since 1945 has focused on whether the decline was relative or an absolute process. As a British industry, shipbuilding illustrates many contradictions inherent in both views; although overtaken by Japanese competition from the mid 1950’s, between 1945-1973 the output and productivity of British shipbuilding increased faster than at any point previously. This paper will discuss the role of the state in this process by using the negotiations between government and the Scott Lithgow shipyard in Scotland concerning the market for 250,000-ton crude oil carriers as an example, demonstrating that the agency of both management and government influenced the eventual outcome more than prevailing market conditions of the time.

  4. Delivery of genetic gain in the interior of British Columbia

    NARCIS (Netherlands)

    Albricht, M.


    The forest industry is important for the province of British Columbia, Canada. Timber harvest is regulated on a sustained yield basis. Productivity can be increased by enhanced reforestation, stand tending and tree improvement thus reducing the area needed to provide the required amount of

  5. Effect of Rubberized Bitumen Blending Methods on Permanent Deformation of SMA Rubberized Asphalt Mixtures

    Directory of Open Access Journals (Sweden)

    Herda Yati Katman


    Full Text Available This study aims at comparing the permanent deformation of Stone Mastic Asphalt (SMA rubberized asphalt mixtures produced by the wet process. In this study, rubberized binders were prepared using two different blending methods, namely, continuous blend and terminal blend. To study the creep behaviour of control and rubberized asphalt mixtures, the dynamic creep test was performed using Universal Materials Testing Apparatus (UMATTA at different temperatures and stress levels. Zhou three-stage creep model was utilized to evaluate the deformation characteristics of the mixtures. In all test conditions, the highest resistance to permanent deformation is showed by the rubberized mixtures produced with continuous blend binders. This study also reveals that the permanent deformation of rubberized mixtures cannot be predicted based on the characteristics of the rubberized binders.

  6. Structural characterization of rubber from jackfruit and euphorbia as a model of natural rubber. (United States)

    Mekkriengkrai, Dararat; Ute, Koiichi; Swiezewska, Ewa; Chojnacki, Tadeusz; Tanaka, Yasuyuki; Sakdapipanich, Jitladda T


    A structural study of low molecular weight rubbers from Jackfruit (Artocarpus heterophyllus) and Painted spurge (Euphorbia heterophylla) was carried out as model compounds of natural rubber from Hevea brasiliensis. The rubber content of latex from Jackfruit was 0.4-0.7%, which is very low compared with that of 30-35% in the latex from Hevea tree. The rubber from Jackfruit latex was low molecular weight with narrow unimodal molecular weight distribution (MWD), whereas that obtained from E. heterophylla showed very broad MWD. The 1H and 13C NMR analyses showed that Jackfruit rubber consists of a dimethylallyl group and two trans-isoprene units connected to a long sequence of cis-isoprene units. The alpha-terminal group of Jackfruit rubber was presumed to be composed of a phosphate group based on the presence of 1H NMR signal at 4.08 ppm corresponding to the terminal =CH-CH2OP group.



    Bustanul Arifin


    The study examines the supply chain of natural rubber production in Indonesia and assessing the transmission of prices to rubber growers and provides recommendations for a suitable scheme that would help to ensure high production standards and a sustainable return for natural rubber production.  The frameworks to examine the performance of supply chain of rubber marketing rely mostly on the efficiency level of marketing system of natural rubbers, including the value chain principles in marke...

  8. Analysis of rubber supply in Sri Lanka

    Energy Technology Data Exchange (ETDEWEB)

    Hartley, M.J.; Nerlove, M.; Peters, R.K. Jr.


    An analysis of the supply response for perennial crops is undertaken for rubber in Sir Lanka, focusing on the uprooting-replanting decision and disaggregating the typical reduced-form supply response equation into several structural relationships. This approach is compared and contrasted with Dowling's analysis of supply response for rubber in Thailand, which is based upon a sophisticated reduced-form supply function developed by Wickens and Greenfield for Brazilian coffee. Because the uprooting-replanting decision is central to understanding rubber supply response in Sri Lanka and for other perennial crops where replanting activities dominate new planting, the standard approaches do not adequately capture supply response.

  9. Devolatilization and Combustion of Tire Rubber and Pine Wood in a Pilot Scale Rotary Kiln

    DEFF Research Database (Denmark)

    Nielsen, Anders R.; Larsen, Morten B.; Glarborg, Peter


    of industrial waste. In this study, devolatilization and combustion of large particles of tire rubber and pine wood with equivalent diameters of 10 mm to 26 mm are investigated in a pilot scale rotary kiln able to simulate the process conditions present in the material inlet end of cement rotary kilns....... Investigated temperatures varied from 700 to 1000 °C, and oxygen concentrations varied from 5% v/v O2 to 21% v/v O2. The devolatilization time of tire rubber and pine wood were found to mainly depend on temperature and particle size and were within 40 to 170 s. Rate limiting parameters for char oxidation...... of tire rubber and pine wood were found to be bulk oxygen concentration, mass transfer rate of oxygen, raw material fill degree, raw material characteristics, and temperature. Kiln rotational speed only had a minor effect on the char oxidation when the raw material bed was in a rolling motion. Initial...

  10. Innovative Application of Biopolymer Keratin as a Filler of Synthetic Acrylonitrile-Butadiene Rubber NBR

    Directory of Open Access Journals (Sweden)

    Mirosława Prochoń


    Full Text Available The current investigations show the influence of keratin, recovered from the tanning industry, on the thermal and mechanical properties of vulcanizates with synthetic rubber acrylonitrile-butadiene rubber NBR. The addition of waste protein to NBR vulcanizates influences the improvement of resistance at high temperatures and mechanical properties like tensile strength and hardness. The introduction of keratin to the mixes of rubber previously blended with zinc oxide (ZnO before vulcanization process leads to an increase in the cross-linking density of vulcanizates. The polymer materials received including addition of proteins will undergo biodecomposition in natural conditions. After soil test, vulcanizates with keratin especially keratin with ZnO showed much more changes on the surface area than vulcanizates without protein. In that aerobic environment, microorganisms, bacteria, and fungus digested better polymer materials containing natural additives.

  11. Promoting the use of crumb rubber concrete in developing countries. (United States)

    Batayneh, Malek K; Marie, Iqbal; Asi, Ibrahim


    The use of accumulated waste materials in third world countries is still in its early phases. It will take courage for contractors and others in the construction industry to recycle selected types of waste materials in the concrete mixes. This paper addresses the recycling of rubber tires accumulated every year in Jordan to be used in concrete mixes. The main objectives of this research were to provide more scientific evidence to support the use of legislation or incentive-based schemes to promote the reuse of accumulated waste tires. This research focused on using crumb tires as a replacement for a percentage of the local fine aggregates used in the concrete mixes in Jordan. Different concrete specimens were prepared and tested in terms of uniaxial compression and splitting tension. The main variable in the mixture was the volumetric percentage of crumb tires used in the mix. The test results showed that even though the compressive strength is reduced when using the crumb tires, it can meet the strength requirements of light weight concrete. In addition, test results and observations indicated that the addition of crumb rubber to the mix has a limited effect toward reducing the workability of the mixtures. The mechanical test results demonstrated that the tested specimens of the crumb rubber concrete remained relatively intact after failure compared to the conventional concrete specimens. It is also concluded that modified concrete would contribute to the disposal of the non-decaying scrap tires, since the amount being accumulated in third world countries is creating a challenge for proper disposal. Thus, obliging authorities to invest in facilitating the use of waste tires in concrete, a fundamental material to the booming construction industry in theses countries, serves two purposes.

  12. Regarding the influence of the particle size of crumb rubber from waste rubber on the physical and mechanical characteristics of reclaimed rubber

    Directory of Open Access Journals (Sweden)

    Dobrotă Dan


    Full Text Available Thus, at present, a large amount of rubber waste cannot be higher harnessed due to recovery technologies used. Also, the requirements for new products of rubber worldwide are greater than the production capacity and the availability of raw materials. To offset this balance is necessary to improve technologies for recycling waste rubber so to can get regenerated rubber with the best mechanical physical characteristics. The main technology for obtaining the regenerated rubber is based on the rubber waste shredding and making the powder, so that it can be carried out de-vulcanization in autoclave. All the time it was monitored as the de-vulcanization process to be as economical and less polluting, and this requires that the sizes of the crumb rubber to be optimal. Thus, in the conducted researches was aimed to establish the particle size of crumb rubber from waste rubber so as to obtain an economical de-vulcanization, but also a reclaimed rubber with superior physical and mechanical characteristics. The organization of researches was made so that crumb of rubber waste was divided into 5 groups, bowing from crumb rubber with particle’s size of 1000 μm (RPS1, and reaching up to crumb rubber with particle’s size of 200 μm (RPS 5.

  13. Identification and subcellular localization analysis of two rubber elongation factor isoforms on Hevea brasiliensis rubber particles. (United States)

    Dai, Longjun; Nie, Zhiyi; Kang, Guijuan; Li, Yu; Zeng, Rizhong


    Rubber elongation factor (REF) is the most abundant protein found on the rubber particles or latex from Hevea brasiliensis (the Para rubber tree) and is considered to play important roles in natural rubber (cis-polyisoprene) biosynthesis. 16 BAC (benzyldimethyl-n-hexadecylammonium chloride)/SDS-PAGE separations and mass spectrometric identification had revealed that two REF isoforms shared similar amino acid sequences and common C-terminal sequences. In this study, the gene sequences encoding these two REF isoforms (one is 23.6 kDa in size with 222 amino acid residues and the other is 27.3 kDa in size with 258 amino acid residues) were obtained. Their proteins were relatively enriched by sequential extraction of the rubber particle proteins and separated by 16 BAC/SDS-PAGE. The localization of these isoforms on the surfaces of rubber particles was further verified by western blotting and immunogold electron microscopy, which demonstrated that these two REF isoforms are mainly located on the surfaces of larger rubber particles and that they bind more tightly to rubber particles than the most abundant REF and SRPP (small rubber particle protein). Copyright © 2016. Published by Elsevier Masson SAS.

  14. Evaluation of thermal insulation and mechanical properties of waste rubber/natural rubber composite

    Directory of Open Access Journals (Sweden)

    M.M. Abdel Kader


    Full Text Available The influences of waste rubber loading on mechanical and thermal conductivity properties were investigated for NR composite. An experimental investigation was carried out to obtain low cost construction material with desirable mechanical and thermal insulation properties. Natural rubber was loaded with different concentrations of waste rubber (200, 400, 600, 800, and 1000 phr. The addition of waste rubber leads to a slight increase in thermal conductivity values of composites but it still lies around range of thermal insulating materials. Also addition of waste rubber leads to improvement of mechanical properties of composites. The crosslink density of NR composite increases with the increase of waste rubber loading until 600 phr and after that it decreases due to the stronger the rubber–filler interaction. This leads to the decrease of the swelling index that has the opposite trend of crosslink density. So, the sample with 600 phr waste rubber is considered the optimum concentration from the swelling measurement. Filler loading results in pronounced increase in the tensile modulus and decease in the elongation at fracture which reflects the reinforcement effect of the filler. The yield stress increases with waste rubber loading increment. This delays the permanent disruption of matrix morphology. So, the optimum concentration which is 600 phr waste rubber loading agrees with the swelling and mechanical measurements which has desirable thermal insulation and high mechanical properties and decreases the cost of materials to 82% of the NR cost.

  15. Characterization of rubber particles and rubber chain elongation in Taraxacum koksaghyz

    Directory of Open Access Journals (Sweden)

    Prüfer Dirk


    Full Text Available Abstract Background Natural rubber is a biopolymer with exceptional qualities that cannot be completely replaced using synthetic alternatives. Although several key enzymes in the rubber biosynthetic pathway have been isolated, mainly from plants such as Hevea brasiliensis, Ficus spec. and the desert shrub Parthenium argentatum, there have been no in planta functional studies, e.g. by RNA interference, due to the absence of efficient and reproducible protocols for genetic engineering. In contrast, the Russian dandelion Taraxacum koksaghyz, which has long been considered as a potential alternative source of low-cost natural rubber, has a rapid life cycle and can be genetically transformed using a simple and reliable procedure. However, there is very little molecular data available for either the rubber polymer itself or its biosynthesis in T. koksaghyz. Results We established a method for the purification of rubber particles - the active sites of rubber biosynthesis - from T. koksaghyz latex. Photon correlation spectroscopy and transmission electron microscopy revealed an average particle size of 320 nm, and 13C nuclear magnetic resonance (NMR spectroscopy confirmed that isolated rubber particles contain poly(cis-1,4-isoprene with a purity >95%. Size exclusion chromatography indicated that the weight average molecular mass (w of T. koksaghyz natural rubber is 4,000-5,000 kDa. Rubber particles showed rubber transferase activity of 0.2 pmol min-1 mg-1. Ex vivo rubber biosynthesis experiments resulted in a skewed unimodal distribution of [1-14C]isopentenyl pyrophosphate (IPP incorporation at a w of 2,500 kDa. Characterization of recently isolated cis-prenyltransferases (CPTs from T. koksaghyz revealed that these enzymes are associated with rubber particles and are able to produce long-chain polyprenols in yeast. Conclusions T. koksaghyz rubber particles are similar to those described for H. brasiliensis. They contain very pure, high molecular mass

  16. Development of rubber-enriched dandelion varieties by metabolic engineering of the inulin pathway. (United States)

    Stolze, Anna; Wanke, Alan; van Deenen, Nicole; Geyer, Roland; Prüfer, Dirk; Schulze Gronover, Christian


    Natural rubber (NR) is an important raw material for a large number of industrial products. The primary source of NR is the rubber tree Hevea brasiliensis, but increased worldwide demand means that alternative sustainable sources are urgently required. The Russian dandelion (Taraxacum koksaghyz Rodin) is such an alternative because large amounts of NR are produced in its root system. However, rubber biosynthesis must be improved to develop T. koksaghyz into a commercially feasible crop. In addition to NR, T. koksaghyz also produces large amounts of the reserve carbohydrate inulin, which is stored in parenchymal root cell vacuoles near the phloem, adjacent to apoplastically separated laticifers. In contrast to NR, which accumulates throughout the year even during dormancy, inulin is synthesized during the summer and is degraded from the autumn onwards when root tissues undergo a sink-to-source transition. We carried out a comprehensive analysis of inulin and NR metabolism in T. koksaghyz and its close relative T. brevicorniculatum and functionally characterized the key enzyme fructan 1-exohydrolase (1-FEH), which catalyses the degradation of inulin to fructose and sucrose. The constitutive overexpression of Tk1-FEH almost doubled the rubber content in the roots of two dandelion species without any trade-offs in terms of plant fitness. To our knowledge, this is the first study showing that energy supplied by the reserve carbohydrate inulin can be used to promote the synthesis of NR in dandelions, providing a basis for the breeding of rubber-enriched varieties for industrial rubber production. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  17. Microcomputing in British planning education


    I Masser; G Teet


    The findings of a survey of British planning schools carried out during spring 1986 suggest that the number of microcomputers available in British planning schools has increased by at least two-and-a-half times over an eighteen-month period. However, compulsory courses on computer applications and information management in these schools still tend to be linked with quantitative methods teaching and few opportunities are provided for more advanced training in information management in most sch...

  18. Visual evoked potentials in rubber factory workers. (United States)

    Tandon, O P; Kumar, V


    Pattern reversal visual evoked potentials (pVEP) were studied in 39 male rubber factory workers in the age range of 18-55 years and 20 control subjects (aged 18-46 years) not exposed to the rubber factory environment. Results revealed that 20 (51%) rubber factory workers had abnormal latencies of wave P1 (dominant component of pVEP) as per accepted criteria of 99% tolerance limit set for the control group (i.e. any value above mean +3 SD of control was considered abnormal). The section-wise per cent distribution of abnormalities was vulcanization (83%), tubing (75%), calendering (60%), loading (38%) and mixing (14%). This study provides electrophysiological evidence that rubber factory environments affect the conduction processes in optical pathways from their origin in the retina to striate cortex. However, this study has its limitations in not identifying the specific chemical(s) causing these changes in VEP.

  19. Oils and rubber from arid land plants (United States)

    Johnson, J. D.; Hinman, C. W.


    In this article the economic development potentials of Cucurbita species (buffalo gourd and others), Simmondsia chinensis (jojoba), Euphorbia lathyris (gopher plant), and Parthenium argentatum (guayule) are discussed. All of these plants may become important sources of oils or rubber.

  20. Contact allergy to rubber accelerators remains prevalent

    DEFF Research Database (Denmark)

    Schwensen, J F; Menné, T; Johansen, J D


    several clinical cases with allergic facial dermatitis to rubber. OBJECTIVES: To evaluate temporal trends of contact allergy to rubber accelerators from the European baseline series in a tertiary patch test clinic in Denmark, and examine associations with anatomical locations of dermatitis. METHODS: Patch...... test and clinical data collected in a Danish tertiary dermatology clinic in Gentofte, Herlev, Copenhagen between 1 January 2005 and 31 December 2014 were analysed. The following rubber accelerators or mixtures in petrolatum from the European baseline patch test series were included: thiuram mix 1.......0%, mercaptobenzothiazole 2.0% and mercapto mix 1.0%. RESULTS: The overall prevalence of contact allergy to rubber accelerators was 3.1% with no significant change during the study period (Ptrend = 0.667). Contact allergy to thiuram mix was the most prevalent and was significantly associated with occupational contact...

  1. Plastics and Rubber Products Manufacturing (NAICS 326) (United States)

    Find environmental regulatory and compliance information for plastics and rubber products manufacturing (which includes the manufacture of cellulose and other fibers) including information about NESHAPs and effluent guidelines for wastewater discharges

  2. Kurumsal Sosyal Sorumluluk Kapsamında Çevre Açıklamaları İle Firma Özellikleri Arasındaki İlişki: Kimya, Petrol, Kauçuk ve Plastik Ürünler Sektöründe Bir Uygulama - Relation Between Company Features And Environmental Statement Within Corporate Social Responsibility: An Application In Chemistry, Petroleum, Rubber And Plastics Products Industry

    Directory of Open Access Journals (Sweden)

    Şule YILDIZ


    Full Text Available The purpose of this research is to determine the relation between company features and environmental statement amounts in the annual activity reports of companies. To this end, activity reports of 19 companies making business in chemistry, petroleum, rubber and plastic products industry in Borsa Istanbul were inspected with content analysis method for 2008 - 2014. The company features inspected within the research are size, equity profitability, active profitability, debt levels, stock market listing date and date of foundation of companies. In the research, the relation between environmental statement level and related company features were analyzed with panel regression model. According to the results of research, the environmental statement level has positive relation with date of foundation and debt level and it has negative relation with size and stock market listing and it is statistically meaningful. However, no statistically meaningful relation was found between equity profitability and asset profitability and the environmental statement level.

  3. Use of waste rubber as concrete additive. (United States)

    Chou, Liang Hsing; Lu, Chun-Ku; Chang, Jen-Ray; Lee, Maw Tien


    For resource reutilization, scrap tyres have long been investigated as an additive to concrete to form 'Rubcrete' for various applications and have shown promising results. However, the addition of rubber particles leads to the degradation of physical properties, particularly, the compressive strength of the concrete. In this study, a theoretical model was proposed to shed light on the mechanisms of decrease in compressive strength due to the addition of rubber particles as well as improvement in compressive strength through modification of particle surfaces. The literature suggests that the compressive strength can be improved by soaking the rubber particles in alkaline solution first to increase the inter-phase bonding between the rubber particles and cement. Instead, we discovered that the loss in compressive strength was due to local imperfections in the hydration of cement, induced by the addition of heterogeneous and hydrophobic rubber particles. Microscopic studies showed that the rubber particles disturbed the water transfer to create channels, which were prone to cracking and led to a loss in the compressive strength. Unexpectedly, no cracking was found along the surfaces of the rubber particles, indicating that the bonding strength between the rubber particles and cement phases was not the critical factor in determining the compressive strength. Therefore, a theoretical model was proposed to describe the water transfer in the Rubcrete specimens to explain the experimental data. In the model, the local water available for hydration (Q) is: Q = -A(slv)/6piv, where Q, A(slv), and v are mass flow rate (kg s(-1)), Hamaker constant (J), and dynamic viscosity (m2 s(-1)), respectively. By maximizing the quantity Q and, in turn, the Hamaker constant A(slv), the compressive strength could be improved. The Hamaker constant A(slv) for water film on rubber particle surfaces was smaller than that for the hydrated cement particles; the water transfer rate was lower in

  4. Mechanical Parameters of Rubber-Sand Mixtures for Numerical Analysis of a Road Embankment (United States)

    Kowalska, Magdalena; Chmielewski, Maciej


    Waste production is one of the greatest problems of the modern world. It is inevitably related to the increase of industrialization. One of the most difficult, and growing in amounts, waste is scrap tyres. The most common method of utilization of end-of-life tyres by their incineration raises much concern in terms of air pollution. More sustainable seems to reuse the tyre derived products – rubber in particular – in civil engineering, where the interesting properties of this material may be effectively utilized. This paper presents results of direct shear strength tests on sand-rubber mixtures, which were next applied to a numerical FEM (finite element method) model of a road embankment built on soft ground. The laboratory tests, conducted for two types of scrap tyre rubber granulates (0.5 – 2 mm and 1 – 5 mm in size) mixed with medium fluvial sand in various proportions (5, 10, 30 and 50% by weight), proved that the unit weight of the mixtures is distinctly smaller that the unit weight of sand alone and at 50% rubber content it drops by half. The internal angle of friction stays almost unchanged for the mixtures with up to 10% of rubber (33 - 37°), but decreases by about 10° when the rubber content increases to 50%. In most of the cases analysed, the cohesion intercept is higher in case of sand-rubber mixtures when compared to sand alone. The numerical model simulated a 4.5 m high embankment with a 3 m thick layer made of sand-rubber mixtures, containing 0%, 10% or 30% of the waste product, founded on a weak subsoil (with a 3 m layer of organic soil). The results showed that stability factor of the structure built with the layer containing 30% of the coarser rubber granulate has increased from 1.60 – for sand only, to 2.15. The embankment was also able to carry load increased from 32 kPa to 45.5 kPa and its base showed much smaller settlement. The results prove that the use of tyre derived aggregates in embankment construction is not only an effective

  5. The use of styrene-butadiene rubber waste as a potential filler in nitrile rubber: order of addition and size of waste particles

    Directory of Open Access Journals (Sweden)

    D. A. Baeta


    Full Text Available Styrene-butadiene rubber (SBR has large applications in the shoe industry, especially as expanded sheets used to produce insoles and inner soles. According to TG analysis, the rubber content in SBR residues (SBR-r was found to be around 26-wt%. Based on that data, a cost-effective technique for the reuse of SBR-r in Nitrile rubber (NBR was developed. Later, the effect of SBR-r on the cure behavior, mechanical performance, swelling, and crosslink density of reused rubber was investigated, with more emphasis placed on the effect of both particle size and loading of waste filler. Cure characteristics such as optimum cure time and scorch time were then reduced by the increasing amount of SBR-r filler. Owing to the reinforced nature of the largest particle size SBR-r, the best results for the mechanical properties of NBR were those in which SBR-r was added at the end of the cure process. The study has thus shown that SBR residue (SBR-r can be used as an economical alternative filler in NBR.

  6. Why Does a Rubber Ball Bounce? The Molecular Origins of Rubber ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 4. Why Does a Rubber Ball Bounce? The Molecular Origins of Rubber Elasticity. V G Geethamma Sabu Thomas. General Article Volume 2 Issue 4 April 1997 pp 48-54 ...

  7. Energy analysis of 108 industrial processes. Phase 1, industrial applications study

    Energy Technology Data Exchange (ETDEWEB)

    Hamel, B. B.; Brown, H. L.


    Extensive data are compiled for energy balances in 108 industrial processes. Specific information on unit operation, material, temperature, unrecoverable losses, along with the process flow diagram is given for each of the industries. The following industries are included: meak packing; milk; canned fruits and vegetables; baked goods; sugar refining; soybean; textiles; wood products; building materials; alkalies and chlorine; inorganic gases; pigments, chemicals; plastic materials and resins; synthetic rubbers; organic fibers; pharmaceutical preparations; organic chemicals; petroleum products; fertilizers; rubber products; glass; blast furnaces and steel mills; metals; farm machinery; motor vehicles; and photographic materials. The SIC's for each industry are identified.

  8. Application of Lignin as Antioxidant in Styrene Butadiene Rubber Composite (United States)

    Liu, Shusheng; Cheng, Xiansu


    Lignin isolated from enzymatic hydrolyzed cornstalks (EHL) is a renewable natural polymer, and rubber is one of the most important polymer materials. The application of EHL in rubber industry is of great significance. The influence of EHL and antioxidant RD on the vulcanizing characteristics, thermal oxidative aging stability under free condition, and water extraction resistance of styrene-butadiene rubber (SBR) were investigated. The effect of EHL/antioxidant D composite antioxidant on the thermal oxidative ageing of SBR was also evaluated. Results showed that the protection of SBR from thermal oxidative aging by EHL/antioxidant D composite antioxidant was superior to that of antioxidant D. This is because EHL molecules have hindered phenol group and have excellent auxiliary antioxidant role with antioxidant D. Moreover, the influence of EHL on the vulcanizing characteristics of SBR compounds was better than that of antioxidant RD, and EHL can reduce the cure rate and increase the optimum cure time. It is because that the EHL molecules have hindered phenol group and methoxy group, which can form a special structure to capture free radical and terminate the chain reaction. The retained tensile strength of SBR compounds with EHL was similar to that of the samples with antioxidant RD, while the retained elongation at break of SBR compounds with EHL was higher than that of the samples with antioxidant RD. In addition, the SBR compounds with EHL have a good water extraction resistance property, which was similar to the samples with antioxidant RD. This is because EHL have large molecular weight, good stability and low solubility in water. In conclusion, due to the low price, abundant resources, non-toxic and pollution-free, etc., EHL will have broad application prospect.

  9. Gene expression analysis and SNP/InDel discovery to investigate yield heterosis of two rubber tree F1 hybrids. (United States)

    Li, Dejun; Zeng, Rizhong; Li, Yan; Zhao, Manman; Chao, Jinquan; Li, Yu; Wang, Kai; Zhu, Lihuang; Tian, Wei-Min; Liang, Chengzhi


    As an important industrial material, natural rubber is mainly harvested from the rubber tree. Rubber tree breeding is inefficient, expensive and time-consuming, whereas marker-assisted selection is a feasible method for early selection of high-yield hybrids. We thus sequenced and analyzed the transcriptomes of two parent rubber trees (RRIM 600 and PR 107) and their most productive hybrids (RY 7-33-97 and RY 7-20-59) to understand their gene expression patterns and genetic variations including single nucleotide polymorphisms (SNPs) and small insertions/deletions (InDels). We discovered >31,000 genetic variations in 112,702 assembled unigenes. Our results showed that the higher yield in F1 hybrids was positively associated with their higher genome heterozygosity, which was further confirmed by genotyping 10 SNPs in 20 other varieties. We also showed that RY 7-33-97 and RY 7-20-59 were genetically closer to RRIM 600 and PR 107, respectively, in agreement with both their phenotypic similarities and gene expression profiles. After identifying ethylene- and jasmonic acid-responsive genes at the transcription level, we compared and analyzed the genetic variations underlying rubber biosynthesis and the jasmonic acid and ethylene pathways in detail. Our results suggest that genome-wide genetic variations play a substantive role in maintaining rubber tree heterosis.

  10. Biological Reclaiming of Recycled Rubber and Its Effect on Mechanical Properties of New Rubber Vulcanizates

    Directory of Open Access Journals (Sweden)

    Maryam Mansourirad


    Full Text Available Nowadays, due to environmental concerns, there has been great attention to recycling and reclaiming of tires. Different methods have been used for reclaiming or desulfurization of rubber. One of these methods, in which desulfurization of rubber happens with no damage to the polymer structure, is desulfurization by biological microorganisms. In this research the application and performance of thermophilic and sulfur oxidizing bacteria, Acidianus brierleyi for this purpose was investigated. Ground tire rubber was detoxified with organic solvents, and the optimum conditions for growing microorganisms in the existence of rubber powder in the shaker flasks were determined. In order to accelerate the process, the suitable conditions for growth of bacteria and desulfurization in the bioreactor were adopted. Fourier transfer infrared spectroscopy and scanning electron microscopy were employed to characterize desulfurization of bio-treated powder from bioreactor. The results indicated that morphological changes on powder surface and reduction of sulfur bonds have occurred. Samples from bioreactors, with and without bacteria and also untreated rubber powder were compounded with virgin styrene butadiene rubber. Tensile and dynamic properties were investigated using uni-direction tensile test and dynamic-mechanical-thermal analysis, respectively. Although some differences in dynamic-mechanical-thermal properties of samples pointed to stronger interaction between rubber matrix and treated rubber powder, no significant improvements in the mechanical properties of vulcanizates containing A.brierleyi-treated powder were observed. Low concentration of sulfur in rubber vulcanizates, chemical bonds of sulfur, and low efficiency of A. brierleyi in breaking sulfur bonds and reclaiming rubber were considered as the reasons for low efficiency of this treatment process.

  11. Respiratory and skin effects of exposure to wood dust from the rubber tree Hevea brasiliensis. (United States)

    Sripaiboonkij, P; Phanprasit, W; Jaakkola, M S


    Potential health effects related to wood dust from the rubber tree, which produces natural rubber latex, have not been previously investigated. The main aim of this study was to investigate the relations of rubber tree dust exposure to respiratory and skin symptoms, asthma and lung function. A cross-sectional study was conducted among 103 workers (response rate 89%) in a rubber tree furniture factory and 76 office workers (73%) in four factories in Thailand. All participants answered a questionnaire and performed spirometry. Inhalable dust levels were measured in different work areas. Factory workers showed increased risk of wheezing, nasal symptoms and asthma compared to office workers. There was a dose-dependent increase in wheeze and skin symptoms in relation to dust level. Significantly increased risks of nasal symptoms (adj OR 3.67, 95% CI 1.45 to 9.28) and asthma (8.41, 1.06 to 66.60) were detected in the low exposure category. Workers exposed to ethyl cyanoacrylate glue had significantly increased risk of cough, breathlessness and nasal symptoms. There was dose-dependent reduction in spirometric lung function with wood dust level. This study provides new evidence that workers exposed to wood dust from the rubber tree experience increased risk of nasal symptoms, wheeze, asthma and skin symptoms and have reduced spirometric lung function. Exposure to cyanoacrylate is related to significantly increased respiratory symptoms. Results suggest that the furniture industry using rubber tree wood should implement appropriate exposure control measures to reduce wood dust exposure and cyanoacrylate glue exposure to protect their employees.

  12. British auditors in Poland in the interwar period

    Directory of Open Access Journals (Sweden)

    Jerzy Cieślik


    Full Text Available This article presents the results of historical research on the operation of British accounting firm Whin-ney, Murray & Co in Poland before World War II. Based on our findings this was the only foreign ac-counting firm active in Poland at that time. Following their clients, British accounting firms expanded their operations abroad at the turn of the 19th century. During the 1920s and 1930s the number of audit assignments on the European continent increased rapidly, which necessitated the establishment of branches (offices in major European cities and industrial districts. Whinney, Murray & Co set up an office in Warsaw in 1932 taking into account its convenient location as a base for undertaking audit assignments throughout the Eastern European region. The Warsaw office concentrated initially on inter-national clients active in Poland but was also engaged in audits of Polish power plants and participated as financial advisor in the electrification program of Polish railways with involvement of British investors. Whinney, Murray & Co contributed to the development of Polish-British economic cooperation before World War II. Its representative was one of the founders of the Polish-British Chamber of Commerce established in Warsaw in 1933.

  13. The British Monarchy On Screen


    Merck, Mandy


    Moving images of the British monarchy, in fact and fiction, are almost as old as the moving image itself, dating back to an 1895 American drama, The Execution of Mary Queen of Scots. British monarchs even appeared in the new ‘animated photography’ from 1896, led by Queen Victoria. Half a century later, the 1953 coronation of Elizabeth II was a milestone in the adoption of television, watched by 20 million Britons and 100 million North Americans. At the century’s end, Princess Diana’s funeral ...

  14. Stimuli-responsive cement-reinforced rubber. (United States)

    Musso, Simone; Robisson, Agathe; Maheshwar, Sudeep; Ulm, Franz-Josef


    In this work, we report the successful development of a cement-rubber reactive composite with reversible mechanical properties. Initially, the composite behaves like rubber containing inert filler, but when exposed to water, it increases in volume and reaches a stiffness that is intermediate between that of hydrogenated nitrile butadiene rubber (HNBR) and hydrated cement, while maintaining a relatively large ductility characteristic of rubber. After drying, the modulus increases even further up to 400 MPa. Wet/drying cycles prove that the elastic modulus can reversibly change between 150 and 400 MPa. Utilizing attenuated total reflection Fourier transform infrared spectroscopy), we demonstrate that the high pH produced by the hydration of cement triggers the hydrolysis of the rubber nitrile groups into carboxylate anions. Thus, the salt bridges, generated between the carboxylate anions of the elastomer and the cations of the filler, are responsible for the reversible variations in volume and elastic modulus of the composite as a consequence of environmental moisture exposure. These results reveal that cement nanoparticles can successfully be used to accomplish a twofold task: (a) achieve an original postpolymerization modification that allows one to work with carboxylate HNBR (HXNBR) not obtained by direct copolymerization of carboxylate monomers with butadiene, and (b) synthesize a stimuli-responsive polymeric composite. This new type of material, having an ideal behavior for sealing application, could be used as an alternative to cement for oil field zonal isolation applications.

  15. On Optimizing an Archibald Rubber-Band Heat Engine. (United States)

    Mullen, J. G.; And Others


    Discusses the criteria and procedure for optimizing the performance of Archibald rubber-band heat engines by using the appropriate choice of dimensions, minimizing frictional torque, maximizing torque and balancing the rubber band system. (GA)

  16. Psychomotor Effects of Mixed Organic Solvents on Rubber Workers

    Directory of Open Access Journals (Sweden)

    O Aminian


    Full Text Available Background: Exposure to organic solvents is common among workers. Objective: To assess neurobehavioral effects of long-term exposure to organic solvents among rubber workers in Tehran, Iran. Methods: Across-sectional study was conducted on 223 employees of a rubber industry. The participants completed a data collection sheet on their occupational and medical history, and demographic characteristics including age, work experience, education level; they performed 6 psychiatric tests on the neurobehavioral core test battery (NCTB that measure simple reaction time, short-term memory (digit span, Benton, eye-hand coordination (Purdue pegboard, pursuit aiming, and perceptual speed (digit symbol. Results: Workers exposed and not exposed to organic solvents had similar age and education distribution. The mean work experience of the exposed and non-exposed workers was 5.9 and 4.4 years, respectively. The exposed workers had a lower performance compared to non-exposed workers in all psychomotor tests. After controlling for the confounders by logistic regression analysis, it was found that exposure to organic solvents had a significant effect on the results of digit symbols, digit span, Benton, aiming, and simple reaction time tests. No significant effect was observed in pegboard test. Conclusion: Occupational exposure to organic solvent can induce subtle neurobehavioral changes among workers exposed to organic solvents; therefore, periodical evaluation of the central nervous system by objective psychomotor tests is recommended among those who are chronically exposed to organic solvents.

  17. Study for the degumming pretreatment of rubber seed oil (United States)

    Li, X. Y.; Chen, Y. B.; Zhang, X.; Souliyathai, D.; Yang, S. P.; Wang, Q.


    With the rapid development of the aviation industry, appearing of the aviation carbon tax and the increasingly serious environmental problems have forced the world to research the development of renewable bio-aviation fuel. Renewable biological aviation fuel contains phosphorus that could reduce the synthesis of noble metal catalysts such as Pd, Pt activity. In order to get low content of phosphorus in degummed oil of non-edible vegetable oil, in this paper, with rubber seed oil as raw material, making the experiment of single factor at the influence of temperature, stirring speed, adding amount of monoethanolamine (MEA) and water amount. The experimental results show that the added amount of MEA is 2.5% in the weight of oil, and temperature is 60°C, while the amount of added water is 2% in the weight of oil, reaction time is 40 min, and stirring speed is 200 r/min. Under these conditions, the phosphorus content of rubber seed oil can be reduced to below 3 mg/kg, degumming rate is 91.37%, and the degumming effects are obvious, which also provides some foundation for follow-up studies.

  18. Electron linear accelerator system for natural rubber vulcanization (United States)

    Rimjaem, S.; Kongmon, E.; Rhodes, M. W.; Saisut, J.; Thongbai, C.


    Development of an electron accelerator system, beam diagnostic instruments, an irradiation apparatus and electron beam processing methodology for natural rubber vulcanization is underway at the Plasma and Beam Physics Research Facility, Chiang Mai University, Thailand. The project is carried out with the aims to improve the qualities of natural rubber products. The system consists of a DC thermionic electron gun, 5-cell standing-wave radio-frequency (RF) linear accelerator (linac) with side-coupling cavities and an electron beam irradiation apparatus. This system is used to produce electron beams with an adjustable energy between 0.5 and 4 MeV and a pulse current of 10-100 mA at a pulse repetition rate of 20-400 Hz. An average absorbed dose between 160 and 640 Gy is expected to be archived for 4 MeV electron beam when the accelerator is operated at 400 Hz. The research activities focus firstly on assembling of the accelerator system, study on accelerator properties and electron beam dynamic simulations. The resonant frequency of the RF linac in π/2 operating mode is 2996.82 MHz for the operating temperature of 35 °C. The beam dynamic simulations were conducted by using the code ASTRA. Simulation results suggest that electron beams with an average energy of 4.002 MeV can be obtained when the linac accelerating gradient is 41.7 MV/m. The rms transverse beam size and normalized rms transverse emittance at the linac exit are 0.91 mm and 10.48 π mm·mrad, respectively. This information can then be used as the input data for Monte Carlo simulations to estimate the electron beam penetration depth and dose distribution in the natural rubber latex. The study results from this research will be used to define optimal conditions for natural rubber vulcanization with different electron beam energies and doses. This is very useful for development of future practical industrial accelerator units.

  19. ‘The men who made the breakthrough’: How the British press represented Patrick Steptoe and Robert Edwards in 1978

    Directory of Open Access Journals (Sweden)

    Katharine Dow


    Full Text Available This article examines how the British press represented Patrick Steptoe and Robert Edwards in the story of the birth of the first ‘test-tube baby’, Louise Brown. In 1978, the British press represented the birth of Louise Brown as both a success and a source of hope. The main pairs of protagonists in this story were Steptoe and Edwards and Lesley and John Brown, who metonymically represented British science and infertile couples, respectively. In the dominant ‘success’ narrative of the birth of Louise Brown as depicted in the British press in 1978, Edwards and Steptoe seemed to embody ‘British’ values of industriousness, perseverance, altruism, ingenuity and teamwork. Thus, their success was simultaneously a British success. With Louise Brown’s birth, in-vitro fertilization came to stand for the potential happiness of infertile people and a bright future for British science and industry.

  20. Lifetime Analysis of Rubber Gasket Composed of Methyl Vinyl Silicone Rubber with Low-Temperature Resistance

    Directory of Open Access Journals (Sweden)

    Young-Doo Kwon


    Full Text Available Most machines and instruments constantly require elastomeric materials like rubber for the purposes of shock absorption, noise attenuation, and sealing. The material properties and accurate lifetime prediction of rubber are closely related to the quality of machines, especially their durability and reliability. The properties of rubber-like elastomers are influenced by ambient conditions, such as temperature, environment, and mechanical load. Moreover, the initial properties of rubber gaskets must be sustained under working conditions to satisfy their required function. Because of its technical merits, as well as its low cost, the highly accelerated life test (HALT is used by many researchers to predict the long-term lifetime of rubber materials. Methyl vinyl silicone rubber (VMQ has recently been adopted to improve the lifetime of automobile radiator gaskets. A four-parameter method of determining the recovery ability of the gaskets was recently published, and two revised methods of obtaining the recovery were proposed for polyacrylate (ACM rubber. The recovery rate curves for VMQ were acquired using the successive zooming genetic algorithm (SZGA. The gasket lifetime for the target recovery (60% of a compressed gasket was computed somewhat differently depending on the selected regression model.

  1. Young British Art / Hanno Soans

    Index Scriptorium Estoniae

    Soans, Hanno, 1974-


    1990ndate kunsti muutumisest. Inglise kunstniku Peter Daviese maalist "Kuum esimene sada" (1996), Gavin Turki vahakujuna valminud autoportreest "Pop". "Young British Art'i" uuskunstist ja Jasper Zoova installatsioonist "F1". Eri analüüsivõimalusi pakkuvatest töödest (Marko Laimre & Ene-Liis Semperi 2000. a. novembri ühisnäituse osa töid).

  2. Medical slang in British hospitals. (United States)

    Fox, Adam T; Fertleman, Michael; Cahill, Pauline; Palmer, Roger D


    The usage, derivation, and psychological, ethical, and legal aspects of slang terminology in medicine are discussed. The colloquial vocabulary is further described and a comprehensive glossary of common UK terms provided in appendix. This forms the first list of slang terms currently in use throughout the British medical establishment.

  3. Mechanical Properties of Graphene-Rubber Nanocomposites (United States)

    Anhar, N. A. M.; Ramli, M. M.; Hambali, N. A. M. A.; Aziz, A. A.; Mat Isa, S. S.; Danial, N. S.; Abdullah, M. M. A. B.


    This research focused on development of wearable sensor device by using Prevulcanized Natural Rubber (PV) and Epoxidized Natural Rubber (ENR 50) latex incorporated with graphene oxide (GO), graphene paste, graphene powder and reduced graphene oxide (rGO) powder. The compounding formulation and calculation were based on phr (parts per hundred rubber) and all the samples were then tested for mechanical properties using Instron 5565 machine. It was found that the sonication effects on tensile strength may have better quality of tensile strength compared to non-sonicated GO. For PV incorporate GO, the optimum loading was best determined at loading 1.5 phr with or without sonication and similar result was recorded for PV/G. For ENR 50 incorporate graphene paste and rGO powder nanocomposite shows the best optimum was at 3.0 phr with 24 hours’ sonication.

  4. Vulcanization and the mechanical response of rubber (United States)

    Kundurthi, S.; Mythravaruni, P.; Ravindran, P.


    Hyperelastic models are widely used to describe the mechanical response of rubber. However, purely mechanical models cannot account for changes in the material due to chemical reactions such as those that take place during vulcanization. Here, we present a model developed within a thermodynamic framework accounting for chemical reactions. A mixture theory approach that allows for the existence of multiple species and their interconversion is followed. The existence of a Helmholtz potential and a rate of entropy production function for the mixture as a whole are posited. Following the multiple natural configuration approach, the rate of entropy production is maximized to obtain constitutive equations. The viscoelastic model is then specialized to the elastic case. The model is calibrated using data available in the literature for rubber. A simulation of the stress-strain curve of rubber as vulcanization progresses is presented.

  5. Synergistic effect of plasma-modified halloysite nanotubes and carbon black in natural rubber-butadiene rubber blend

    NARCIS (Netherlands)

    Poikelispaa, Minna; Das, Amit; Dierkes, Wilma K.; Vuorinen, Jyrki


    Halloysite nanotubes (HNTs) were investigated concerning their suitability for rubber reinforcement. As they have geometrical similarity with carbon nanotubes, they were expected to impart a significant reinforcement effect on the rubber compounds but the dispersion of the nanofillers is difficult.

  6. The use of plasticizing additives based on recycled raw materials in the petrochemical rubber mixtures

    Directory of Open Access Journals (Sweden)

    Z. S. Shashok


    Full Text Available At present, the development of alternative products for elastomers based on recycling petrochemical raw materials is a new trend of the rubber industry progress. Petrochemical raw materials include spent lubricants and motor oils are among such recycling products. In this context, the influence of the products of recycling waste engine oil (DVCH and RA in comparison with industrial oil (I-20 on the technological properties of filled elastomeric compositions was investigated. The elastomeric compositions were based on poly isoprene and divinyl rubbers. The plasticizing components were manufactured by IOOO “DVCH-Menedzhment”. They are mixture of hydro-carbons, C16–C20 and differ from each other in the content of linear and branched paraffin. Plastic-elastic properties of rubber compounds on the shear disk viscometer MV2000 in accordance with GOST 10722–76 was carried out. Kinetics of vulcanization on the rheometer ODR2000 according to GOST 12535–84 was defined. It is shown that the introduction of RA test plasticizing component provides a significant effect on Mooney viscosity, as compared to elastomeric compositions containing a plasticizer and I-20 and plasticizing additive DVCH. It revealed that the administration of all components in the studied plasticizing elastomer compositions based on a combination poly isoprene and divinyl rubbers has no significant effect on the rate of relaxation of stress of rubber compounds. It is found that elastomeric compositions containing as additives investigated processing waste oil products (DVCH and RA are characterized by a slightly smaller value of time to reach an optimal degree of vulcanization.

  7. Economic status, smoking, occupational exposure to rubber, and lung cancer: a case-cohort study. (United States)

    Li, Ke; Yu, Shunzhang


    Recent studies tend consistently to confirm the presence of a moderate excess risk of lung cancer in the rubber industry. However, the agent responsible for the excess of lung cancer is still obscure. Also, analyses without regard to the modifying effects of sex, economic status, and smoking habit are less than satisfactory. To explore these questions, we have conducted a case-cohort study using the data of 51 lung cancer deaths in 1973-1997 and a random sample (sub-cohort) of 188 from among 1598 subjects in a rubber factory in Shanghai, China. We computed the risks of lung cancer by economic status, smoking habit, coal fumes in home, and year of first employment. We assessed lung cancer risks for occupational exposures, unadjusted and adjusted for economic status and smoking. After confounding effects of smoking and economic status were controlled, we found that rate ratios were 1.43 (95% confidence interval (CI) 0.43-4.69), 1.79 (95% CI 0.64-5.03), and 3.76 (95% CI 1.44-9.86) for 1-14, 15-29, and 30-45 exposure-years in curing department, respectively. The data showed significant trends in increased risk of lung cancer with duration of exposure in tire-curing department (score test for trend:, P = 0.004). However, in front rubber processing (weighing and mixing, calendering, extruding, and milling), no significant excess risk of lung cancer was found. If it can be confirmed that nitrosamines are mainly generated in back rubber processing (curing and vulcanizing), it would be reasonable to conclude that excess risk of lung cancer in rubber industry is attributable, at least partially, to exposure to nitrosamines.

  8. 27 CFR 21.125 - Rubber hydrocarbon solvent. (United States)


    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Rubber hydrocarbon solvent. 21.125 Section 21.125 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU....125 Rubber hydrocarbon solvent. (a) Rubber hydrocarbon solvent is a petroleum derivative. (b...

  9. Economic analysis of intercropping rubber ( Hevea Brasiliensis ) in ...

    African Journals Online (AJOL)

    This study was carried out in 2007/2008 planting season to evaluate the economics of intercropping rubber among smallholder rubber farmers of Edo and Delta States, through a survey of 54 rubber farmers in a multi stage, purposive and simple random sampling techniques. Data collected were analyzed using budgetary ...

  10. Adoption of improved rubber production technologies by farmers in ...

    African Journals Online (AJOL)

    This study examined the adoption of improved rubber production technologies by farmers in Akwa Ibom State, Nigeria. The specific objectives of the study are to; identify improved rubber production technologies disseminated to farmers, identify methods for disseminating information on improved rubber production ...

  11. Modified Silicone-Rubber Tooling For Molding Composite Parts (United States)

    Baucom, Robert M.; Snoha, John J.; Weiser, Erik S.


    Reduced-thermal-expansion, reduced-bulk-modulus silicone rubber for use in mold tooling made by incorporating silica powder into silicone rubber. Pressure exerted by thermal expansion reduced even further by allowing air bubbles to remain in silicone rubber instead of deaerating it. Bubbles reduce bulk modulus of material.

  12. An overview of the potentials of natural rubber (Hevea brasiliensis ...

    African Journals Online (AJOL)



    Dec 29, 2009 ... An overview of the potentials of natural rubber (Hevea ... prospects and potentials of transgenic rubber plant as a unique .... tapping is a non-destructive method of latex extraction .... markers have been developed for the rubber tree. Genes ... the International Symposium on Molecular Farming in Plants Asia.

  13. Economic Analysis of Intercropping Rubber (Hevea brasiliensis) in ...

    African Journals Online (AJOL)

    Mr D.Y. Giroh

    This study was carried out in 2007/2008 planting season to evaluate the economics of intercropping rubber among smallholder rubber farmers of Edo and Delta States, through a survey of 54 rubber farmers in a multi stage, purposive and simple random sampling techniques. Data collected were analyzed using budgetary ...

  14. Thermoreversibly Cross-Linked EPM Rubber Nanocomposites with Carbon Nanotubes

    NARCIS (Netherlands)

    Polgar, Lorenzo Massimo; Criscitiello, Francesco; van Essen, Machiel; Araya-Hermosilla, Rodrigo; Migliore, Nicola; Lenti, Mattia; Raffa, Patrizio; Picchioni, Francesco; Pucci, Andrea


    Conductive rubber nanocomposites were prepared by dispersing conductive nanotubes (CNT) in thermoreversibly cross-linked ethylene propylene rubbers grafted with furan groups (EPM-g-furan) rubbers. Their features were studied with a strong focus on conductive and mechanical properties relevant for

  15. An overview of the potentials of natural rubber ( Hevea brasiliensis ...

    African Journals Online (AJOL)

    The International Rubber Research Organizations have successfully developed transgenic rubber plants that produce foreign proteins of potential commercial value. Among such routines is an antibody and human serum albumin. Tapping rubber trees for valuable proteins will be more profitable compared to other options.

  16. Investigations on cementitious composites based on rubber particle waste additions

    Directory of Open Access Journals (Sweden)

    Glaucio Laun Nacif


    Full Text Available The amount of waste rubber has gradually increased over recent years because of over-growing use of rubber products. The disposal of waste rubber has caused serious environmental problems. The incorporation of recycled materials into cementitious composites is a feasible alternative that has gained ground in civil construction. The performance of such materials is much affected not only by the rubber addition, but also the particle size which has been controversially reported in the literature. In order to investigate the single effect of rubber particles into cement based materials, rubber cementitious composites were prepared with no silica particle additions. A full factorial design has been conducted to assess the influence of the rubber particle size (0.84/0.58 mm and 0.28/0.18 mm; mass fraction used (5, 15 and 30%; and water/cement ratio (0.35 and 0.50 on the physic-mechanical properties of the composites. The materials were characterized through apparent density, porosity, compressive strength, flexural strength, modulus of elasticity and microstructural analysis. The interactions of rubber particle size, rubber fraction and water/cement ratio affected significantly the density and compressive strength of the composites. The apparent porosity was influenced mainly by the rubber particle size. The flexural strength was affected by the main factors and the modulus of elasticity was affected by the interaction factors rubber particle size and fraction, and rubber fraction and w/c ratio.

  17. Investigations on cementitious composites based on rubber particle waste additions

    Directory of Open Access Journals (Sweden)

    Glaucio Laun Nacif


    Full Text Available The amount of waste rubber has gradually increased over recent years because of over-growing use of rubber products. The disposal of waste rubber has caused serious environmental problems. The incorporation of recycled materials into cementitious composites is a feasible alternative that has gained ground in civil construction. The performance of such materials is much affected not only by the rubber addition, but also the particle size which has been controversially reported in the literature. In order to investigate the single effect of rubber particles into cement based materials, rubber cementitious composites were prepared with no silica particle additions. A full factorial design has been conducted to assess the influence of the rubber particle size (0.84/0.58 mm and 0.28/0.18 mm; mass fraction used (5, 15 and 30%; and water/cement ratio (0.35 and 0.50 on the physic-mechanical properties of the composites. The materials were characterized through apparent density, porosity, compressive strength, flexural strength, modulus of elasticity and microstructural analysis. The interactions of rubber particle size, rubber fraction and water/cement ratio affected significantly the density and compressive strength of the composites. The apparent porosity was influenced mainly by the rubber particle size. The flexural strength was affected by the main factors and the modulus of elasticity was affected by the interaction factors rubber particle size and fraction, and rubber fraction and w/c ratio.

  18. Effect of micro sized marble sludge on physical properties of natural rubber composites

    Directory of Open Access Journals (Sweden)

    Ahmed Khalil


    Full Text Available Marble waste as sludge is collected from Marble industry, as a way of solving the environmental problem of industrial waste. The sludge was dried, ground and passed through desire sieves (10, 15, 20, 37 and 75 μm, This powder was characterized by the X-ray fluorescence technique and then incorporated in the formulation of NR composites with different loading of micro sized MS particles (20, 40, 60, 80 and 100 parts per hundred of rubber, phr. The cure characteristics, mechanical properties and swelling properties of MS/NR composites were evaluated. Results indicate that minimum torque, maximum torque, tensile strength, modulus, tear strength, hardness, crosslink density were increased while the scorch time, cure time, cure rate, cure rate index (CRI, elongation at break, compression set, rebound resilience, abrasion loss, swelling coefficient, average molecular weight and filler-rubber interaction decrease with increasing MS loading.

  19. Replacement of Carbon Black on Natural Rubber Composites and Nanocomposites — Part 1 (United States)

    Martín-Cortés, Guillermo R.; Esper, Fabio J.; de Araujo, Antonio J. Santana; Hennies, Wildor T.; Valenzuela, Maria G. Silva; Valenzuela-Díaz, Francisco R.

    Seeking to replace carbon-black as filler of rubber in the production of vulcanized goods, researchers from University of São Paulo have studied different materials types as minerals, vegetal or wastes agricultural and industry. Results of rubber composites filled with MA1 a waste of mineral treatment provided by Esper Industries are presented. MA1 was characterized through X-ray diffraction; Thermal analysis; Scanning Electronic Microscopy; and others laboratory methods. The composite and shaped masses were evaluated by these methods plus their mechanical properties such as tensile strength, elongation at break and hardness. Exceptional results were obtained in the mechanical properties evaluated, better than those obtained with the traditional carbon-black. Seeing the kind of material used as filler, it can conclude that the environmental benefit is present, as well as economic development, giving credibility to the use of these alternative material in replacement carbonblack.


    Directory of Open Access Journals (Sweden)

    T. I. Igumenova


    Full Text Available A number of studies on heat buildup in tire rubber surface scan method samples using a thermal imaging camera. Investigated the exothermic chemical reaction mechanical destruction rubber when loading designs permanent cyclic stretching with deformation of the working zone 50%. Percentage of deformation of the working zone was chosen on the basis of the actual data on the stretch-compression zone "Rusk" tires, which is the maximum level difference of deformation during run-in. Experiment plan provided for periodic relaxation samples of at least 72 hours for more accurate simulation of operation process of structural products. Created and processed data on temperature changes in samples for bar and line profile for rubber compounds with the introduction of nanomodifiers (fulleren technical carbon in comparison with the control sample without him. The data obtained reflect the nature of heat depending on the composition of the compound. Identified common patterns of thermal nature of physico-chemical process mechanical destruction rubbers. For rubber with nanomodifikatorom there has been an increase in the temperature interval reaction from a minimum to a maximum 2 degrees that is also linked to the rise in the average temperature of the reaction on the histogram also at 2-3 degrees of deformation under the same conditions and the level of cyclic loading. However, the temperature in the control sample that is associated with the beginning of the formation of hardened rubber structures, economies of Mallinz-Petrikeev, occurs with delay twice compared with modified Fullerenes. Measurement of physic-mechanical indicators selected in the course of testing of samples showed the beginning of formation of structure with increased strength of samples in the sample temperature zone that corresponds to the thermal effect of èndotermičeskomu recombination reactions of macromolecules.

  1. Cancer mortality and occupational exposure to aromatic amines and inhalable aerosols in rubber tire manufacturing in Poland.

    NARCIS (Netherlands)

    de Vocht, F.; Sobala, W.; Wilczynska, U.; Kromhout, H.; Szeszenia-Dabrowska, N.; Peplonska, B.


    AIM: Most data on carcinogenic risk in the rubber industry are based on data from Western countries. This study assessed cancer risks in a retrospective cohort in a Polish tire manufacturing plant, relying on quantified exposure to inhalable aerosols and aromatic amines instead of job titles or

  2. Oxygen exchange in silicone rubber capillaries. (United States)

    Heineken, F G; Predecki, P K; Filley, G F


    Capillaries of 7 and 12.5 mu diameter have been fabricated in silicone rubber. Whole blood treated with heparin has been perfused through these capillaries. Under flowing conditions, no clotting or other clumping effects have been observed and red cells appear to maintain a constant velocity. Oxygen transfer data to and from saline perfusing the 12.5 mu diameter capillaries have been obtained in order to determine how rapidly O2 will permeate the silicone rubber film. The data indicate that the capillaries simulate lung tissue oxygen exchange and will allow for the first time the experimental determination of oxygen exchange kinetics in flowing whole blood.

  3. Rheological testing of crumb rubber modified bitumen

    CSIR Research Space (South Africa)

    Mturi, GAJ


    Full Text Available are shown in Table 1, typically (Xiao et al., 2006) containing Carbon, Oxygen, Silicon, Sulphur and traces of the metals: Calcium, Sodium, Aluminium and Zinc from the vulcanization component, Zinc Oxide (ZnO) (Mark et al., 2005). 3-5 August... for The relationship between the optimum gap distance and the rubber crumb particle size was calculated. The gap distance was found to be between the rubber crumb particles prior to blending determined through extraction as suggested by Attia and Abdelrahman...

  4. High Performance Graphene Oxide Based Rubber Composites


    Yingyan Mao; Shipeng Wen; Yulong Chen; Fazhong Zhang; Pierre Panine; Tung W. Chan; Liqun Zhang; Yongri Liang; Li Liu


    In this paper, graphene oxide/styrene-butadiene rubber (GO/SBR) composites with complete exfoliation of GO sheets were prepared by aqueous-phase mixing of GO colloid with SBR latex and a small loading of butadiene-styrene-vinyl-pyridine rubber (VPR) latex, followed by their co-coagulation. During co-coagulation, VPR not only plays a key role in the prevention of aggregation of GO sheets but also acts as an interface-bridge between GO and SBR. The results demonstrated that the mechanical prope...

  5. The Treatment of Sludge from the Rubber Processing Industry with ...

    African Journals Online (AJOL)

    ... readily available, cheap and easy to handle, more biodegradable, therefore more environmentally friendly. The use of the coagulant for the treatment of sludge and indeed where coagulation and flocculation is desirous can be so recommended. Keywords: Biodegradable, Chitosan, Exoskeleton, Pollution, Sludge,.

  6. Treatment of wastewater from rubber industry in Malaysia

    African Journals Online (AJOL)



    Sep 20, 2010 ... producing the biogas as a useful energy sources are some advantages of anaerobic wastewater treatment system (Kantachote et al., 2008). However, this treatment results in the formation of H2S due to consumption of sulphate instead of oxygen by sulphate-reducing bacteria. H2S is toxic and increases ...

  7. Small scale industrial application of rubber seed oil in soap ...

    African Journals Online (AJOL)

    Its pH was slightly basic which makes it suitable for use in soap manufacture. It was, therefore, used as a substitute for palm kernel oil in the production of soaps (bar soap and detergent soap). Tests for the foam capacity and stability of the soaps exhibited good visual foam stabilities and capacities. These make it suitable for ...

  8. Constraints to sustainable development of rubber industry in Nigeria ...

    African Journals Online (AJOL)

    The findings revealed that lack of inputs, lack of credit facilities, high production cost are some of the constraints to sustainable development. The study also revealed among others the causes of the constraints, which include high lending interest rate, diversion of loan by farmers, low exchange rate of the Naira and old age ...

  9. Treatment of wastewater from rubber industry in Malaysia ...

    African Journals Online (AJOL)

    African Journal of Biotechnology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 9, No 38 (2010) >. Log in or Register to get access to full text downloads.


    Research was conducted to develop methods of surface applications of antiozonants to rubber items and evaluate antiozonants for packaging rubber...items in plastic bags. The report covers (1) tests of packaging rubber items in polyethylene bags together with various antiozonants , and (2) tests of

  11. In situ reactive compatibilization of natural rubber/acrylic-bentonite composites via peroxide-induced vulcanization

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Lihua; Lei, Zhiwen [Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004 (China); Xu, Chuanhui, E-mail: [Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004 (China); Chen, Yukun, E-mail: [The Key Laboratory of Polymer Processing Engineering, Ministry of Education, China(South China University of Technology), Guangzhou, 510640 (China)


    To achieve good interfacial interaction between fillers and rubber matrix is always a hot topic in rubber reinforcing industry. In this paper, acid activated bentonite (Bt) was alkalified to be alkaline calcium-bentonite (ACBt), then acrylic acid (AA) was employed to modify ACBt to obtain acrylic-bentonite (ABt). The results of Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) illustrated that acrylate groups were chemically boned onto the surface of Bt and the layer spacing of Bt was increased. During peroxide-induced vulcanization, in situ compatibilization of ABt was realized via the reaction between the unsaturated bonds of acrylate groups on the surface of Bt and the natural rubber (NR) chains. This resulted in an enhanced cross-linked network which contributed to the improved mechanical properties of NR/ABt composites. - Highlights: • Acrylate groups were chemically boned onto the surface of bentonite. • In situ compatibilization was realized via the reaction of acrylate group and NR. • ABt particles participated in forming the NR crosslink network. • A potential reinforcing material options for “white” rubber products.

  12. A new mechanism for selective adsorption of rubber on carbon black surface caused by nano-confinement in SBR/NBR solution (United States)

    Kawazoe, Masayuki

    A novel mechanism of selective adsorption of rubber molecules onto carbon black surface in a binary immiscible rubber blend solution has been proposed in this dissertation. The phenomenon leads to uneven distribution of carbon black to the specific polymer in the blend and the obtained electrically conductive composite showed drastic reduction of percolation threshold concentration (PTC). The mechanism and the feature of conductive network formation have much potential concerning both fundamental understanding and industrial application to improve conductive polymer composites. In chapter I, carbon black filled conductive polymer composites are briefly reviewed. Then, in chapter II, a mechanism of rubber molecular confinement into carbon black aggregate structure is introduced to explain the selective adsorption of a specific rubber onto carbon black surface in an immiscible rubber solution blend (styrene butadiene rubber (SBR) and acrylonitrile butadiene rubber (NBR) with toluene or chloroform). Next, in chapters III and IV, polymers with various radius of gyration (Rg) and carbon blacks with various aggregate structure are examined to verify the selective adsorption mechanism. Finally, in chapter V, the novel mechanism was applied to create unique meso-/micro-unit conductive network in carbon black dispersed SBR/NBR composites.

  13. Simulation Process Analysis of Rubber Shock Absorber for Machine Tool

    Directory of Open Access Journals (Sweden)

    Chai Rong Xia


    Full Text Available The simulation on rubber shock absorber of machine tool was studied. The simple material model of rubber was obtained by through the finite element analysis software ABAQUS. The compression speed and the hardness of rubber material were considered to obtain the deformation law of rubber shock absorber. The location of fatigue were confirmed from the simulation results. The results shown that the fatigue position is distributed in the corner of shock absorber. The degree of deformation is increased with increasing of compress speed, and the hardness of rubber material is proportional to deformation.

  14. Investigation of surface halide modification of nitrile butadiene rubber (United States)

    Sukhareva, K. V.; Mikhailov, I. A.; Andriasyan, Yu O.; Mastalygina, E. E.; Popov, A. A.


    The investigation is devoted to the novel technology of surface halide modification of rubber samples based on nitrile butadiene rubber (NBR). 1,1,2-trifluoro-1,2,2-trichlorethane was used as halide modifier. The developed technology is characterized by production stages reduction to one by means of treating the rubber compound with a halide modifier. The surface halide modification of compounds based on nitrile butadiene rubber (NBR) was determined to result in increase of resistance to thermal oxidation and aggressive media. The conducted research revealed the influence of modification time on chemical resistance and physical-mechanical properties of rubbers under investigation.

  15. Industrial Training Practices. (United States)

    Beverstock, A.G.

    Based primarily on British conditions, this volume concentrates on methods of industrial training for production workers, craftsmen and technicians, office personnel, technicians and technologists, supervisors, marketing and sales personnel, and the junior, middle, and senior or executive levels of management. General principles and fundamental…

  16. Preparation of sulfonic acid-containing rubbers from natural rubber vulcanizates (United States)

    Poonsawat, Worapong; Poompradub, Sirilux; Ngamcharussrivichai, Chawalit


    In this work, a series of sulfonic acid-containing rubbers were prepared by aqueous phase oxidation of natural rubber vulcanizates in the presence of hydrogen peroxide (H2O2) and formic acid (HCOOH). The starting vulcanizates were neatly prepared via an efficient vulcanization (EV) system by varying mass ratio of N-cyclohexyl-2-benzothiazole sulfonamide (CBS), as an accelerator, to sulfur. The oxidation conditions were controlled at the molar ratio of H2O2: HCOOH = 1:1, the concentration of H2O2 = 15 wt.%, the temperature = 50 °C, and the reaction time = 3 h. The rubber materials before and after the oxidation were characterized for their physicochemical properties by using Fourier transform infrared spectroscopy, bomb calorimetry, acid-base titration and swelling measurements. The results indicated the presence of sulfonic acid group in the oxidized rubbers, generated by the oxidative cleaves of sulfide crosslinks in the rubber vulcanizates. The oxidation decreased the sulfur content of the rubber in which the level of sulfur loss was determined by the CBS/sulfur ratio. Moreover, the acidity of the oxidized products was correlated with the amount of sulfur remaining.

  17. Filled liquid silicone rubbers: Possibilities and challenges

    DEFF Research Database (Denmark)

    Yu, Liyun; Vudayagiri, Sindhu; Zakaria, Shamsul Bin


    Liquid silicone rubbers (LSRs) have been shown to possess very favorable properties as dielectric electroactive polymers due to their very high breakdown strengths (up to 170 V/μm) combined with their fast response, relatively high tear strength, acceptable Young’s modulus as well as they can...

  18. Rubber Recycling: Chemistry, Processing, and Applications

    NARCIS (Netherlands)

    Myhre, M.; Saiwari, Sitisaiyidah; Dierkes, Wilma K.; Noordermeer, Jacobus W.M.


    For both environmental and economic reasons, there is broad interest in recycling rubber and in the continued development of recycling technologies. The use of postindustrial materials is a fairly well-established and documented business. Much effort over the past decade has been put into dealing

  19. Chemical changes in rubber allergens during vulcanization. (United States)

    Bergendorff, Ola; Persson, Christina; Lüdtke, Anna; Hansson, Christer


    Allergic contact dermatitis to rubber is caused by residues of chemicals used in manufacturing a rubber product. Several different additives are used to achieve a final product of the desired characteristics. Accelerators such as thiurams, dithiocarbamates, and mercaptobenzothiazoles are often among the additives responsible for allergic reactions recognized by dermatologists. The chemistry of the vulcanization process is complicated; as it occurs at an elevated temperature with a mixture of reactive chemicals, the compositions of the initial and final products differ. This paper investigates the changes in composition of common allergens during vulcanization, doing so by chemically analysing various rubber formulations at different stages of the process. Major changes were found in which added chemicals were consumed and new ones produced. An important observation is that thiuram disulfides rarely appear in the final rubber although they may have been used as additives. Instead, thiurams are often converted to dithiocarbamates or to products formed by addition to mercaptobenzothiazole structures, if these have been used together with thiurams as accelerators.

  20. Valorisation of Proteins from Rubber Tree

    NARCIS (Netherlands)

    Widyarani,; Coulen, Stef C.W.; Sanders, Johan P.M.; Bruins, Marieke E.


    Purpose: The objective of this study was to identify the availability, possible applications, and economic potential of proteins that are present in different parts of the rubber tree. Proteins from non-food sources can be used in e.g. animal feed or biochemicals production with no or little

  1. Numerical modelling of rubber vibration isolators

    NARCIS (Netherlands)

    Beijers, C.A.J.; de Boer, Andries; Nilsson, A.; Boden, H.


    An important cause for interior noise in vehicles is structure-borne sound from the engine. The vibrations of the source (engine) are transmitted to the receiver structure (the vehicle) causing interior noise in the vehicle. For this reason the engine is supported by rubber isolators for passive

  2. Why Do Calculators Have Rubber Feet? (United States)

    Heavers, Richard M.


    Our students like using the covers of their TI graphing calculators in an inquiry-based extension of a traditional exercise that challenges their preconceived ideas about friction. Biology major Fiona McGraw (Fig. 1) is obviously excited about the large coefficient of static friction ([mu][subscript s] = 1.3) for the four little rubber feet on her…

  3. Larch sawfly in British Columbia

    Energy Technology Data Exchange (ETDEWEB)

    Unger, L.


    Summary of the history of infestations in British Columbia of the larch sawfly, first introduced into the province in 1930. Information is based on the Forest Insect and Diseases Survey records and data and preliminary observations on the impact of defoliation on growth of western larch. The report describes biology; history of outbreaks in western larch and tamarack; sampling, population assessments, and predictions; damage appraisal; and controls, including parasites, predators, and weather.

  4. Investigation of chlorinated modifier content influence on the physical-mechanical properties and vulcanizing characteristics of rubber and rubber mixture (United States)

    Sukhareva, K. V.; Mikhailov, I. A.; Andriasyan, Yu O.; Popov, A. A.


    Present paper is devoted to the novel solution for the chlorination technology of polyolefin and diene rubbers – mechanochemical halide modification, as a more efficient way to obtain halogenated elastomers with a wide range of halogen content (from 3 to 7 %). The vulcanizing characteristics of elastomeric compounds based on the chlorinated rubber compounds as well as the production conditions of vulcanization process have been studied by the methods of dynamic mechanical rheometry. The performed investigation revealed the influence of chlorine content in different types of rubber compounds on rheological and physical-mechanical properties. New halogen-containing polyolefins rubbers produced by this technology proved themselves in the conditions of the rubber production.

  5. Cancer mortality and morbidity among rubber workers. (United States)

    Monson, R R; Fine, L J


    Mortality and morbidity from cancer among a cohort of 13,570 white male rubber workers were examined. Each man worked for at least 5 years at the Akron, Ohio, plant of the B. F. Goodrich Company. The potential period of follow-up was from January 1, 1940 to June 30, 1976. Departmental work histories were based primarily on records maintained by Local no. 5, United Rubber Workers. The occurrence of cancer was measured by death certificates and by a survey of Akron-area hospital tumor registries from 1964 to 1974. Two types of analyses were made: 1) an external comparison of mortality rates of rubber workers versus rates of U.S. white males, and 2) an internal comparison of cancer morbidity rates among persons who were employed in various work areas of the plant. Excess cases of specific cancers (observed/expected numbers) among workers in specific work areas included: stomach and intestine: rubber making (30/14.4); lung: tire curing (31/14.1), fuel cells and/or deicers (46/29.1); bladder: chemical plant (6/2.4), and tire building (16/10.7); skin cancer: tire assembly (12/1.9); brain cancer: tire assembly (8/2.0); lymphatic cancer: tire building (8/3.2); and leukemia: calendering (8/2.2), tire curing (8/2.6), tire building (12/7.5), elevators (4/1.4), tubes (4/1.6), and rubber fabrics (4/1.1). Agents that may be responsible for these excesses were considered.

  6. Molecular mechanism of ethylene stimulation of latex yield in rubber tree (Hevea brasiliensis) revealed by de novo sequencing and transcriptome analysis. (United States)

    Liu, Jin-Ping; Zhuang, Yu-Fen; Guo, Xiu-Li; Li, Yi-Jian


    Rubber tree (Hevea brasiliensis) is an important industrial crop cultivated in tropical areas for natural rubber production. Treatment of the bark of rubber trees with ehephon (an ethylene releaser) has been a routine measure to increase latex yield, but the molecular mechanism behind the stimulation of rubber production by ethylene still remains a puzzle. Deciphering the enigma is of great importance for improvement of rubber tree for high yield. De novo sequencing and assembly of the bark transciptomes of Hevea brasiliensis induced with ethephon for 8 h (E8) and 24 h (E24) were performed. 51,965,770, 52,303,714 and 53,177,976 high-quality clean reads from E8, E24 and C (control) samples were assembled into 81,335, 80,048 and 80,800 unigenes respectively, with a total of 84,425 unigenes and an average length of 1,101 bp generated. 10,216 and 9,374 differentially expressed genes (DEGs) in E8 and E24 compared with C were respectively detected. The expression of several enzymes in crucial points of regulation in glycolysis were up-regulated and DEGs were not significantly enriched in isopentenyl diphosphate (IPP) biosynthesis pathway. In addition, up-regulated genes of great regulatory importance in carbon fixation (Calvin cycle) were identified. The rapid acceleration of glycolytic pathway supplying precursors for the biosynthesis of IPP and natural rubber, instead of rubber biosynthesis per se, may be responsible for ethylene stimulation of latex yield in rubber tree. The elevated rate of flux throughout the Calvin cycle may account for some durability of ethylene-induced stimulation. Our finding lays the foundations for molecular diagnostic and genetic engineering for high-yielding improvement of rubber tree.

  7. Colonization and community: the Vancouver Island coalfield and the making of the British Columbian working class

    Energy Technology Data Exchange (ETDEWEB)

    Belshaw, J.D. [University College of the Cariboo, Kamloops, BC (Canada). Department of Philosophy, History, and Politics


    During the nineteenth century, coal miners from Europe, Asia, and eastern North America settled on Vancouver Island, British Columbia to mine coal deposits at Nanaimo, Wellington, and Cumberland. The factors that attracted British miners and their families, their expectations and ambitions, and their integration into mining communities are discussed. Working conditions, household wages, racism, industrial organization, gender, schooling, leisure, and community building and identity are considered.

  8. Preliminary studies of the rubber from unserviceable tires irradiated by electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Clecia M.; Silva, Leonardo G. Andrade e, E-mail: [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)


    Nowadays there is a growth in the developing processes for modification of polymers with ionizing radiation (gamma rays, electron beam) for several industrial applications. An option is ionizing radiation process due to their capacity of inducing crosslinking and scission on a wide range of polymeric materials without initiators or chemicals products. This method has significant advantages on economical and ecological fields, when compared to chemical, thermal and mechanical process. The rubber recycling has been extensively discussed, mainly related to tire. There are reports with data about production and consumption of rubber and unserviceable tire. There is very few information about the destination of others rubber items, incineration and landfill are the main methods for elimination of unserviceable tire, however those methods are not environmentally friendly. It is necessary to study better and effective methods to recycle and to give value to rubber residue. This work is about the use of ionizing radiation for the recovery and/or reuse and processing rubber of unserviceable tire. The samples were irradiated with 200, 400 and 600 kGy radiation dose, 22.39 kGy/s dose rates, at room temperature and in the presence of air using an 1.5 MeV electron beam accelerator. The irradiated and non-irradiated samples were studied by thermogravimetry (TG). The analyses were performed from room temperature up to 600 deg C, heating rate of 10 deg C/min in the presence of nitrogen (N{sub 2}) and air. By this technique it was possible to observe the effects of the radiation dose on the weight loss. (author)

  9. Fabrication of Extrinsically Conductive Silicone Rubbers with High Elasticity and Analysis of Their Mechanical and Electrical Characteristics

    Directory of Open Access Journals (Sweden)

    Anjum Saleem


    Full Text Available Conductive plastics are attracting more and more interest in electronics due to their light weight and inability to rust, which are common problems associated with metals. The field of conducting plastics is not new. Much work has been done to impart electrical conductivity to mechanically strong polymers such as polypropylene, polycarbonate and epoxies, etc. However there is a need to fabricate more flexible and elastic conductive polymers such as conducting silicone rubbers for use in various applications. In this work silicone rubbers reinforced with conductive fillers have been fabricated for use as sensors in textiles to detect the resistance change produced by stretching or relaxing. The variations of electrical resistance have been investigated by stretching and releasing the strands of conductive rubbers as a function of time. Two types of silicone rubbers—addition cured and condensation cured—were compounded with different electrically conductive fillers, among which carbon fibers have shown the best results. The carbon fibers improved the electrical conductance of the rubbers, even in very low weight percentages. The increasing concentration of fillers decreases the elasticity of the rubber. In order to keep the original properties of silicones, the filler concentration was kept as low as possible to produce a significantly detectable signal. The fabricated compounds were analyzed for their mechanical properties by stress strain curves. Such materials find their applications in electronics, antistatic applications, sports and the automotive industry where they can be used as deformation sensors.

  10. Simulation of Rubber Friction Using Viscoelastic Behavior of Rubber and Roughness Parameters of Surfaces

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Arab Bafrani


    Full Text Available One of the most important factors that affect tire friction is surface roughness, which determines the size of the real contact area, real pressure distribution on the contact interface, and scales of mechanical engagement between viscoelastic rubber and a rough substrate. The need to predict coefficient of friction (COF for rubber on rough surfaces for applications such as traction of tires on the road surfaces led to some physical models such as Heinrich-Kluppel’s model. The current study examines the applicability of the Heinrich-Kluppel model, using different viscoelastic representations, in numerical simulations of COF for rubber, and its agreement with the experimental results. For this purpose, roughness characteristics of the surfaces and viscoelastic properties of rubber were measured by fractal analysis and dynamic-mechanical-thermal analysis (DMTA, respectively. These data were employed in the numerical code to simulate COF for a rubber sample. The model was also modified by replacing the Zener viscoelastic representation in the original model with the generalized Maxwell viscoelastic representation. On the other hand, COF for rubber was measured on the same rough surface (different sand-papers by an in-house friction tester, and results were compared with the numerical results. It was shown that computer simulation could predict the load and speed dependence of rubber friction very well. The application of the generalized Maxwell model improved agreement between the numerical and experimental results for high sliding speeds where the Zener viscoelastic model failed to predict the right trend in variation of COF with speed. This speed range was matched with the sliding velocities in the footprint of tire under rolling conditions.

  11. Genome-wide identification of rubber tree (Hevea brasiliensis Muell. Arg.) aquaporin genes and their response to ethephon stimulation in the laticifer, a rubber-producing tissue. (United States)

    Zou, Zhi; Gong, Jun; An, Feng; Xie, Guishui; Wang, Jikun; Mo, Yeyong; Yang, Lifu


    Natural rubber, an important industrial raw material, is specifically synthesized in laticifers located inside the rubber tree (Hevea brasiliensis Muell. Arg.) trunk. Due to the absence of plasmodesmata, the laticifer water balance is mediated by aquaporins (AQPs). However, to date, the characterization of H. brasiliensis AQPs (HbAQPs) is still in its infancy. In this study, 51 full-length AQP genes were identified from the rubber tree genome. The phylogenetic analysis assigned these AQPs to five subfamilies, including 15 plasma membrane intrinsic proteins (PIPs), 17 tonoplast intrinsic proteins (TIPs), 9 NOD26-like intrinsic proteins (NIPs), 4 small basic intrinsic proteins (SIPs) and 6 X intrinsic proteins (XIPs). Functional prediction based on the analysis of the aromatic/arginine (ar/R) selectivity filter, Froger's positions and specificity-determining positions (SDPs) showed a remarkable difference in substrate specificity among subfamilies. Homology analysis supported the expression of 44 HbAQP genes in at least one of the examined tissues. Furthermore, deep sequencing of the laticifer transcriptome in the form of latex revealed a key role of several PIP subfamily members in the laticifer water balance, and qRT-PCR analysis showed diverse expression patterns of laticifer-expressed HbAQP genes upon ethephon treatment, a widely-used practice for the stimulation of latex yield. This study provides an important genetic resource of HbAQP genes, which will be useful to improve the water use efficiency and latex yield of Hevea.

  12. The redefinition of the american and british gas industries: the regulation of the access load to the gas pipelines networks; La restructuration des industries gazieres americaine et britannique: la reglementation de la charge d'acces aux reseaux de gazoducs

    Energy Technology Data Exchange (ETDEWEB)

    David, L


    The transport and distribution networks regulation is the main stakes of the regulation reform of the gas industries. This thesis analyzes the models applied in The Usa and in the United Kingdom. The first part deals with the gas industries deregulation in these two countries, the impacts on the economy and the organization of the gas industries. The second part presents a theoretical approach of the regulation applied to the prices of the natural ags transport by gas pipelines. Regulation by the service cost price and by price cap are compared. (A.L.B.)

  13. Prediction of the Styrene Butadiene Rubber Performance by Emulsion Polymerization Using Backpropagation Neural Network

    Directory of Open Access Journals (Sweden)

    Yan-jiang Jin


    Full Text Available The effect of the amounts of initiator, emulsifier, and molecular weight regulator on the styrene butadiene rubber performance was investigated, based on the industrial original formula. It was found that the polymerization rate was increased with the increased dosage of initiator and emulsifier, and together with replenishing molecular weight regulator will make the Mooney viscosity of rubber meet the national standard when the conversion rate reaches 70%. The backpropagation neural network was trained by the original formula and ameliorated formula on the basis of Levenberg-Marquardt algorithm, and the relative error between the simulation results and experimental data is less than 1%. The good consistency shows that the BP neural network could predict the product performances in different formula conditions. It would pave the way for adjustment of the SBR formulation and prediction of the product performances.

  14. Comparative numerical study on the optimal vulcanization of rubber compounds through traditional curing and microwaves (United States)

    Milani, Gabriele; Milani, Federico


    The main problem in the industrial production process of thick EPM/EPDM elements is constituted by the different temperatures which undergo internal (cooler) and external regions. Indeed, while internal layers remain essentially under-vulcanized, external coating is always over-vulcanized, resulting in an overall average tensile strength insufficient to permit the utilization of the items in several applications where it is required a certain level of performance. Possible ways to improve rubber output mechanical properties include a careful calibration of exposition time and curing temperature in traditional heating or a vulcanization through innovative techniques, such as microwaves. In the present paper, a comprehensive numerical model able to give predictions on the optimized final mechanical properties of vulcanized 2D and 3D thick rubber items is presented and applied to a meaningful example of engineering interest. A detailed comparative numerical study is finally presented in order to establish pros and cons of traditional vulcanization vs microwaves curing.

  15. Uniaxial tension test on Rubber at constant true strain rate

    Directory of Open Access Journals (Sweden)

    Sourne H.L.


    Full Text Available Elastomers are widely used for damping parts in different industrial contexts because of their remarkable dissipation properties. Indeed, they can undergo severe mechanical loading conditions, i.e., high strain rates and large strains. Nevertheless, the mechanical response of these materials can vary from purely rubber-like to glassy depending on the strain rate undergone. Classically, uniaxial tension tests are made in order to find a relation between the stress and the strain in the material at various strain rates. However, even if the strain rate is searched to be constant, it is the nominal strain rate that is considered. Here we develop a test at constant true strain rate, i.e. the strain rate that is experienced by the material. In order to do such a test, the displacement imposed by the machine is an exponential function of time. This test has been performed with a high speed hydraulic machine for strain rates between 0.01/s and 100/s. A specific specimen has been designed, yielding a uniform strain field (and so a uniform stress field. Furthermore, an instrumented aluminum bar has been used to take into account dynamic effects in the measurement of the applied force. A high speed camera enables the determination of strain in the sample using point tracking technique. Using this method, the stress-strain curve of a rubber-like material during a loading-unloading cycle has been determined, up to a stretch ratio λ = 2.5. The influence of the true strain rate both on stiffness and on dissipation of the material is then discussed.

  16. Hysteroscopic tubal occlusion with silicone rubber. (United States)

    Reed, T P; Erb, R


    A new method of sterilization for women is being investigated in several outpatient centers. The technique involves flowing liquid silicone rubber into the fallopian tubes. The silicone cures in place and forms a rubbery solid plug. The catalyzed liquid silicone is pumped through a special polysulfone guide assembly that fits through the operating channel of a standard hysteroscope. On the end of the guide is a hollow premolded silicone rubber tip that fits into the cornual ostium of the tube. When the silicone cures it also cross-links to this tip so that the tip becomes part of the plug. Results as of April 1, 1982, from 350 women in the Philadelphia center suggest that proper plug formation prevents pregnancy and that the method can be applied to about 85% of properly selected women.

  17. Properties of Waste Tire Rubber Powder

    Directory of Open Access Journals (Sweden)

    M. Bekhiti


    Full Text Available Scrap tires are abundant and alarming waste. The aggregates resulting from the crushing of the waste tires are more and more used in the field of civil engineering (geotechnical, hydraulic works, light concretes, asphaltic concretes, etc.. Depending on the type of the used tires, dimensions and possible separations and treatment, the physical and mechanical characteristics of these aggregates might change. Some physical, chemical and direct shear tests were performed on three gradation classes of waste tire rubber powder. The tests results were combined with data from previous studies to generate empirical relationships between cohesion, friction angle and particle size of waste tire powder rubber. A cubic (third order regression model seems to be more appropriate compared to linear and quadratic models.

  18. On the response of rubbers at high strain rates.

    Energy Technology Data Exchange (ETDEWEB)

    Niemczura, Johnathan Greenberg (University of Texas-Austin)


    In this report, we examine the propagation of tensile waves of finite deformation in rubbers through experiments and analysis. Attention is focused on the propagation of one-dimensional dispersive and shock waves in strips of latex and nitrile rubber. Tensile wave propagation experiments were conducted at high strain-rates by holding one end fixed and displacing the other end at a constant velocity. A high-speed video camera was used to monitor the motion and to determine the evolution of strain and particle velocity in the rubber strips. Analysis of the response through the theory of finite waves and quantitative matching between the experimental observations and analytical predictions was used to determine an appropriate instantaneous elastic response for the rubbers. This analysis also yields the tensile shock adiabat for rubber. Dispersive waves as well as shock waves are also observed in free-retraction experiments; these are used to quantify hysteretic effects in rubber.

  19. Biodiesel Production from Rubber Seed Oil via Esterification Process

    Directory of Open Access Journals (Sweden)

    W Widayat


    Full Text Available One promise source of alternative energy is biodiesel from rubber seed oil, because the raw materials available in plentiful quantities and can be renewed. In addition, the rubber seed is still lack of utilization, and Indonesia is one of the largest rubbers producing country in the world. The objective of this research is to studied on biodiesel production by esterification process. Parameters used in this study are the ratio of catalyst and temperature and its influence on the characteristics of the resulting biodiesel product. Characterization of rubber seed include acid content number analysis, saponification numbers, density, viscosity, iodine number, type of free fatty acids and triglyceride oils. The results of analysis showed that rubber seed oil content obtained is 50.5%. The results of the GCMS analysis showed that a free fatty acid level in rubber seed is very high. Conversion into bio-diesel oil is obtained by at most 59.91% and lowest 48.24%.

  20. Demotivating factors influencing rubber production workers


    Mohammad Reza Iravani


    Motivation is one of the most important factors influencing workers' productivity. An increase in workers' motivation could add more value to organizations' structure and influence the profitability, significantly. In this paper, we study different factors on demotivating workers using questionnaire consist of various questions. The questionnaire is distributed among some employees who work for rubber production units located in Esfahan, Iran. The results of this survey indicate that discrimi...

  1. Teleoncology uptake in British Columbia. (United States)

    Clarke, Melissa; Barnett, Jeff


    Telehealth enables the delivery of specialized health care to patients living in isolated and remote regions. The purpose of this analysis is to determine the current uptake of teleoncology in mainland British Columbia. Patient appointment data was extracted from the Cancer Agency Information System (CAIS) for the 2009 calendar year. Three types of practitioners used teleoncology in 2009: Medical Oncologists, Genetic Counsellors and Medical Geneticists. In total, 712 telehealth encounters were conducted; Medical Oncologists conducted 595 encounters (83.6%), Genetic Counsellors conducted 112 encounters (15.7%) and Medical Geneticists conducted 5 encounters (0.7%). The most common oncology appointments were Gastro-Intestinal (11.4%) and Lymphoma (11.0%) follow-up appointments with a Medical Oncologist. Telehealth encounters were conducted by 46 individual health care providers however, a single Medical Oncologist conducted 418 encounters and this accounts for more than half (58.7%) of all telehealth appointments in 2009. Radiation Oncologists on the mainland up to this point are not using the technology. The Local Health Areas with the highest number of oncology telehealth appointments were: Kamloops: 203 encounters (34.1%), Penticton: 84 encounters (14.1%), Cranbrook: 58 encounters (9.7%) and the Southern Okanagan: 33 encounter (5.5%). Use of telehealth in rural and remote areas of BC is limited and there is significant room for growth. Further research will be required to identify barriers and restrictions to the use of telehealth in order to increase teleoncology adoption in British Columbia.

  2. Mortality among rubber workers: V. processing workers. (United States)

    Delzell, E; Monson, R R


    Cause-specific mortality was evaluated among 2,666 men employed in the processing division of a rubber manufacturing plant. The division was divided into two sections: front processing (compounding, mixing and milling operations) and back processing (extrusion, calendering, cement mixing and rubberized fabrics operations). Mortality rates for all processing workers combined and for men in each section were compared with rates for U.S. White males or for workers employed in other divisions of the same plant. Compared with either referent group, men in the processing division had increased mortality from leukemia, emphysema, and cancers of the stomach, large intestine, and biliary passages and liver. An excess number of deaths from stomach and larger intestine cancer was found predominantly among men in the front processing section (33 observed vs. 17.7 expected deaths, based on rates in nonprocessing workers). Increased mortality from leukemia (14 observed vs. 7.3 expected) and from emphysema (22 observed vs. 11.0 expected) was present among men employed in the back processing section. Examination of mortality from these causes according to age and the year starting work, duration of employment, and years since starting work in the relevant sections of the processing division suggested that observed excesses of stomach cancer, large intestine cancer, leukemia, and emphysema among processing workers are related to occupational exposures. These results are consistent with the findings of studies of other groups of rubber workers.

  3. High Performance Graphene Oxide Based Rubber Composites (United States)

    Mao, Yingyan; Wen, Shipeng; Chen, Yulong; Zhang, Fazhong; Panine, Pierre; Chan, Tung W.; Zhang, Liqun; Liang, Yongri; Liu, Li


    In this paper, graphene oxide/styrene-butadiene rubber (GO/SBR) composites with complete exfoliation of GO sheets were prepared by aqueous-phase mixing of GO colloid with SBR latex and a small loading of butadiene-styrene-vinyl-pyridine rubber (VPR) latex, followed by their co-coagulation. During co-coagulation, VPR not only plays a key role in the prevention of aggregation of GO sheets but also acts as an interface-bridge between GO and SBR. The results demonstrated that the mechanical properties of the GO/SBR composite with 2.0 vol.% GO is comparable with those of the SBR composite reinforced with 13.1 vol.% of carbon black (CB), with a low mass density and a good gas barrier ability to boot. The present work also showed that GO-silica/SBR composite exhibited outstanding wear resistance and low-rolling resistance which make GO-silica/SBR very competitive for the green tire application, opening up enormous opportunities to prepare high performance rubber composites for future engineering applications.

  4. High Performance Graphene Oxide Based Rubber Composites (United States)

    Mao, Yingyan; Wen, Shipeng; Chen, Yulong; Zhang, Fazhong; Panine, Pierre; Chan, Tung W.; Zhang, Liqun; Liang, Yongri; Liu, Li


    In this paper, graphene oxide/styrene-butadiene rubber (GO/SBR) composites with complete exfoliation of GO sheets were prepared by aqueous-phase mixing of GO colloid with SBR latex and a small loading of butadiene-styrene-vinyl-pyridine rubber (VPR) latex, followed by their co-coagulation. During co-coagulation, VPR not only plays a key role in the prevention of aggregation of GO sheets but also acts as an interface-bridge between GO and SBR. The results demonstrated that the mechanical properties of the GO/SBR composite with 2.0 vol.% GO is comparable with those of the SBR composite reinforced with 13.1 vol.% of carbon black (CB), with a low mass density and a good gas barrier ability to boot. The present work also showed that GO-silica/SBR composite exhibited outstanding wear resistance and low-rolling resistance which make GO-silica/SBR very competitive for the green tire application, opening up enormous opportunities to prepare high performance rubber composites for future engineering applications. PMID:23974435

  5. Boron-Loaded Silicone Rubber Scintillators

    CERN Document Server

    Bell, Z W; Maya, L; Sloop, F V J


    Silicone rubber received attention as an alternative to polyvinyltoluene in applications in which the scintillator is exposed to high doses because of the increased resistance of the rubber to the formation of blue-absorbing color centers. Work by Bowen, et al., and Harmon, et al., demonstrated their properties under gamma/x-ray irradiation, and Bell, et al. have shown their response to thermal neutrons. This last work, however, provided an example of a silicone in which both the boron and the scintillator were contained in the rubber as solutes, a formulation which led to the precipitation of solids and sublimation of the boron component. In the present work we describe a scintillator in which the boron is chemically bonded to the siloxane and so avoids the problem of precipitation and loss of boron to sublimation. Material containing up to 18% boron, by weight, was prepared, mounted on photomultipliers, and exposed to both neutron and gamma fluxes. Pulse height spectra showing the neutron and photon respons...

  6. Design, manufacturing and testing of Controllable Rubber Trailing Edge Flaps

    DEFF Research Database (Denmark)

    Løgstrup Andersen, Tom; Aagaard Madsen, Helge; Barlas, Thanasis K

    The overall goal for the INDUFLAP project was realization of a test facility for development and test of Controllable Rubber Trailing Edge Flaps (CRTEF) for wind turbines. This report covers experimental work at DTU Wind Energy including design, manufacture and test of different configurations...... of flaps with voids in chord- or spanwise direction. Development of rubber flaps has involved further design improvements. Non-metallic spring elements and solutions for sealing of continuous extruded rubber profiles have been investigated....

  7. Vulcanization Kinetics of Natural Rubber Based On Free Sulfur Determination


    Abu Hasan; Rochmadi Rochmadi; Hary Sulistyo; Suharto Honggokusumo


    The determination of free sulfur in the rubber vulcanizates provided significant representation of vulcanization reaction. In this research, the effects of vulcanization temperature, the mixing method of carbon black into rubber, the ingredients mixing sequence and the type of carbon black were studied on masticated and milled natural rubber in which the reaction was observed by un-reacted sulfur determination. The results showed that higher vulcanization temperature provided faster vulcaniza...

  8. Impact resistance of concrete – using slit rubber from tyres


    Coventry, Kathryn; Richardson, Alan; Diaz, Eli


    This paper examines recycled tyre rubber, which was machine cut into slits and these were added to Portland cement concrete mixes in different percentages, based on specimen volume. They were then tested to determine the impact performance of each mix in comparison to a plain non-rubberised mix. \\ud The results indicated that concrete samples containing recycled rubber, exhibited a loss in compressive strength when compared to the plain concrete mix, however, the rubber modified samples were ...

  9. 75 FR 36472 - Goodyear Tire and Rubber Company, Receipt of Petition for Decision of Inconsequential Noncompliance (United States)


    ... National Highway Traffic Safety Administration Goodyear Tire and Rubber Company, Receipt of Petition for Decision of Inconsequential Noncompliance Goodyear Tire and Rubber Company, (Goodyear),\\1\\ has determined... 573, Defect and Noncompliance Responsibility and Reports. \\1\\ Goodyear Tire and Rubber Company...

  10. Magnesium affects rubber biosynthesis and particle stability in Ficus elastica, Hevea brasiliensis and Parthenium argentatum (United States)

    Natural rubber biosynthesis occurs in laticifers of Ficus elastica and Hevea brasiliensis, and in parenchyma cells of Parthenium argentatum. Natural rubber is synthesized by rubber transferase using allylic pyrophosphates as initiators, isopentenyl pyrophosphate as monomeric substrate and magnesium ...

  11. Characterization of asphalt cements modified with crumbed rubber from discarded tires : final report. (United States)


    The potential legislative requirement for incorporation of scrap rubber into asphalt blends mandated a thorough evaluation of the influence of scrap rubber additives on the physical properties and aging characteristics of rubber/asphalt blends. Blend...

  12. Barrierity of hydrogenated butadiene-acrylonitrile rubber and butyl rubber after exposure to organic solvents. (United States)

    Krzemińska, Sylwia; Rzymski, Władysław M


    Resistance of antichemical clothing primarily depends on the type of material it is made from, in particular on the type of polymer used for coating the fabric carrier. This paper reports on systematic investigations on the influence of the cross-linking density of an elastomer and the composition of a cross-linked elastomer on its resistance to permeation of selected organic solvents. Tests of barrier material samples made from nonpolar butyl rubber (IIR) and polar hydrogenated butadiene-acrylonitrile rubber (HNBR) showed that (a) in rubber-solvent systems with medium thermodynamic affinity, cross-linking density influenced resistance to permeation and (b) the polarity of the system had a significant influence on barrierity.

  13. Elucidation of filler-to-filler and filler-to-rubber interactions in silica-reinforced natural rubber by TEM Network Visualization

    NARCIS (Netherlands)

    Sarkawi, S.S.; Dierkes, Wilma K.; Noordermeer, Jacobus W.M.


    Filler-to-rubber interaction is a key parameter in the reinforcement of rubber. This paper presents an investigation into filler-to-filler and filler-to-rubber interactions in silica-reinforced natural rubber (NR) in the presence and absence of a silane coupling agent. Using a special network

  14. Interpersonal perception in Japanese and British observers. (United States)

    Kito, Tsuneo; Lee, Billy


    We compared performance of Japanese and British observers in deciphering images depicting Japanese interpersonal relationships. 201 Japanese and 215 British subjects were assessed by means of a test consisting of 31 photograph problems accompanied by two or three alternative solutions one of which was correct. Japanese subjects outperformed British subjects on the test overall (z = 3.981, p interpersonal relationships, but it may sometimes cause specific errors. Differences in the perceptual cues used suggest that British subjects had difficulty reading Japanese facial expressions.

  15. Geotechnical Properties of Rubber Tires and Sediments Mixtures

    Directory of Open Access Journals (Sweden)

    H. Sellaf


    Full Text Available An experimental work was undertaken to study the effect of rubber tires on the geotechnical properties of a dredged sediment, using a mixing ratio of large size. For comparison, two types of soil were studied (dredged sediment from Fergoug dam and Tizi Tuff from the north west of Algeria. Taking into account the high compressibility and the low water absorption of the rubber tires, grain size analysis, density, Atterberg limits analysis, chemical composition, direct shear tests, loading-unloading tests, modified Proctor and CBR tests are performed on the two soils and their mixtures with different scrap tire rubber (10, 20, 25 and 50%. The results show that liquid limits and plastic indexes decrease with the scrap tire rubber content and that the decrease is more significant for soil with high plasticity. Cohesion also decreases with scrap tire rubber content when the internal friction angle is vacillating. Compression and recompression indexes increase gradually with the scrap tire rubber content and the variation for compression index is more significant for the two soils. Compaction characteristics and CBR values decrease with scrap tire rubber content. The CBR values for W=3% are important compared to those with W=5% excepted for mixture with (75% tuff and 25% scrap tire rubber. The results show that the scrap tire rubber can be used as a reinforcement material for dredged soil, but with a content that should not highly affect the compressibility.

  16. Analysis of residual vulcanization accelerators in baby bottle rubber teats. (United States)

    Yamazaki, T; Inoue, T; Yamada, T; Tanimura, A


    An analytical method was established for the determination of dialkyldithiocarbamates (DTCs) in chloroform-acetone extracts from rubber teats for baby bottles. DTCs in the extracts were derivatized into ethyl esters and analysed by gas chromatography employing nitrogen-phosphorus detection. Dimethyldithiocarbamate and diethyldithiocarbamate were detected at levels up to 3.2 micrograms/g rubber and up to 4.6 micrograms/g rubber (as dithiocarbamic acid), respectively, in the extracts from commercially available isoprene rubber tests. DTCs can form secondary amines by acid hydrolysis, although the levels of DTCs in the extracts only made a minor contribution to the total level of measured secondary amine precursors.

  17. British government, industry agree to fund Hotel launcher studies (United States)

    Brown, D. A.


    A program status assessment is presented for the horizontal takeoff and landing 'Hotol' single-stage-to-orbit space launcher, for which parallel, two-year airframe and propulsion system proof-of-concept studies have been approved. A two-year initial development program for the airframe would be followed by a four-year development and manufacturing phase that would begin upon the propulsion system concept's successful demonstration. Flight trials could begin in 1996. A number of significant modifications have already been made to the initial design concept, such as to the foreplanes, afterbody, engine intake, and orbital control system.

  18. Thermal Analysis Characterization of Elastomers and Carbon Black Filled Rubber Composites for Army Applications (United States)


    RUBBER COMPOSITES FOR ARMY APPLICATIONS 6. PERFORMING ORO. REPORT NUMBER 7. AUTHOR(q) S. CONTRACT OR GRANT NUMBER(41) Robert E. Sacher, Domenic P...Roadwheei Side SP - Standard Products SBR - Styrene-butadiene Rubber SR - Synthetic Rubber ( SBR or SBR -BR) TR - Track Rubber U - Uncured iii... applications ranging from automotive and aircraft tires to rubber belts, hoses, and seals. Although thermal studies on rubber materials closely

  19. Industrial Hardening: 1981 Technical Status-Report. (United States)


    that are sensitive to rapid shutdown would include petroleum refining and petrochemicals, rubber and plastics, and chemical and fertilizer plants. The...HEAVY-DUTY IMPACT MILLS DESCRIPTION INDUSTRIES WHERE USED Cage mills Quarries, phosphate, fertilizer , colors, presscake (e.g. vegetable oils...bauxite, rollers that operate in coke, magnesite , iron oxide pigments, conjunction with grinding sulfur, talc, graphite, calcium phosphates, rings


    Directory of Open Access Journals (Sweden)

    Vyacheslav K. Mayevski


    Full Text Available This paper describes a mathematical model of an industrial chemical reactor for production of synthetic rubber. During reactor operation the model parameters vary considerably. To create a control algorithm performed transformation of mathematical model of the reactor in order to obtain a dependency that can be used to determine the model parameters are changing during reactor operation.

  1. Adhesion of nitrile rubber to UV-assisted surface chemical modified PET fabric, part II: Interfacial characterization of MDI grafted PET

    Energy Technology Data Exchange (ETDEWEB)

    Razavizadeh, Mahmoud; Jamshidi, Masoud, E-mail:


    Highlights: • In this research UV-irradiated PET fabric was chemically modified. • The fabric at first carboxylated under UV irradiation using glutaric anhydride, then it was grafted using isocyanate (i.e. MDI). • The surface of the fabric was characterized before and after each treating satge. • The composite samples were prepared and tested for T-Peel test. The surfaces of the fabrics were surface characterized to understand. - Abstract: Fiber to rubber adhesion is an important subject in rubber industry. It is well known that surface treatment (i.e. physical, mechanical and chemical) is an effective method to improve interfacial bonding of fibers and/or fabrics to rubbers. UV irradiation is an effective method which has been used to increase fabric-rubber interfacial interactions. In this research UV assisted chemical modification of PET fabrics was used to increase PET to nitrile rubber (NBR) adhesion. Nitrile rubber is a perfect selection as fuel and oil resistant rubber. However it has weak bonding to PET fabric. For this purpose PET fabric was carboxylated under UV irradiation and then methylenediphenyl diisocyanate (MDI) was grafted on carboxylated PET. The chemical composition of the fabric before and after surface treatment was investigated by X-ray photoelectron spectroscopy (XPS). The sectional morphology of the experimental PET fibers and the interface between rubber compound and PET fabric was studied using scanning electron microscope (SEM). The morphology and structure of the product were analyzed by an energy dispersive X-ray spectrometer (EDX). FTIR-ATR and H NMR analysis were used to assess surface modifications on the PET irradiated fabrics.

  2. The comparison of properties and cost of material use of natural rubber and sand in manufacturing cement mortar for construction sub-base layer (United States)

    Rahman, R.; Nemmang, M. S.; Hazurina, Nor; Shahidan, S.; Khairul Tajuddin Jemain, Raden; Abdullah, M. E.; Hassan, M. F.


    The main issue related to this research was to examine the feasibility of natural rubber SMR 20 in the manufacturing of cement mortar for sub-base layer construction. Subbase layers have certain functions that need to be fulfilled in order to assure strong and adequate permeability of pavement performance. In a pavement structure, sub-base is below the base and serves as the foundation for the overall pavement structure, transmitting traffic loads to the sub-grade and providing drainage. Based on this research, the natural rubber, SMR 20 was with the percentages of 0%, 5%, 10% and 15% to mix with sand in the manufacture of the cement mortar. This research describes some of the properties and cost of the materials for the natural rubber and sand in cement mortar manufacturing by laboratory testing. Effects of the natural rubber replacement on mechanical properties of mortar were investigated by laboratory testing such as compressive strength test and density. This study obtained the 5% of natural rubber replaced in sand can achieved the strength of normal mortar after 7 days and 28 days. The strength of cement mortar depends on the density of cement mortar. According to the cost of both materials, sand shows the lower cost in material for the cement mortar manufacturing than the uses of natural rubber. Thus, the convectional cement mortar which used sand need lower cost than the modified rubber cement mortar and the most economical to apply in industrial. As conclusion, the percentage of 5% natural rubber in the cement mortar would have the same with normal cement mortar in terms of the strength. However, in terms of the cost of the construction, it will increase higher than cost of normal cement mortar production. So that, this modified cement mortar is not economical for the road sub-base construction.

  3. Mapping tropical forests and deciduous rubber plantations in Hainan Island, China by integrating PALSAR 25-m and multi-temporal Landsat images (United States)

    Chen, Bangqian; Li, Xiangping; Xiao, Xiangming; Zhao, Bin; Dong, Jinwei; Kou, Weili; Qin, Yuanwei; Yang, Chuan; Wu, Zhixiang; Sun, Rui; Lan, Guoyu; Xie, Guishui


    Updated and accurate maps of tropical forests and industrial plantations, like rubber plantations, are essential for understanding carbon cycle and optimal forest management practices, but existing optical-imagery-based efforts are greatly limited by frequent cloud cover. Here we explored the potential utility of integrating 25-m cloud-free Phased Array type L-band Synthetic Aperture Radar (PALSAR) mosaic product and multi-temporal Landsat images to map forests and rubber plantations in Hainan Island, China. Based on structure information detected by PALSAR and yearly maximum Normalized Difference Vegetation Index (NDVI), we first identified and mapped forests with a producer accuracy (PA) of 96% and user accuracy (UA) of 98%. The resultant forest map showed reasonable spatial and areal agreements with the optical-based forest maps of Fine Resolution Observation and Monitoring Global Land Clover (FROM-GLC) and GlobalLand30. We then extracted rubber plantations from the forest map according to their deciduous features (using minimum Land Surface Water Index, LSWI) and rapid changes in canopies during Rubber Defoliation and Foliation (RDF) period (using standard deviation of LSWI) and dense canopy in growing season (using maximum NDVI). The rubber plantation map yielded a high accuracy when validated by ground truth-based data (PA/UA > 86%) and evaluated with three farm-scale rubber plantation maps (PA/UA >88%). It is estimated that in 2010, Hainan Island had 2.11 × 106 ha of forest and 5.15 × 105 ha of rubber plantations. This study has demonstrated the potential of integrating 25-m PALSAR-based structure information, and Landsat-based spectral and phenology information for mapping tropical forests and rubber plantations.

  4. British Celtic influence on English phonology

    NARCIS (Netherlands)

    Laker, Stephen


    The dissertation assesses the influence of British Celtic on the phonological development of English during and shortly after the Anglo-Saxon settlement period, ca. AD 450–700. By reconstructing and then comparing the phonological systems of both British Celtic and English at the time of contact, an

  5. Relationship satisfaction among Turkish and British adults


    Celenk, O.; Van de Vijver, F.J.R.; Goodwin, R.


    We tested three theories (adult attachment, autonomy/relatedness, and gender roles) to understand relationship satisfaction among 150 British and 170 Turkish adults, all involved in romantic relationships. Avoidance, relatedness, autonomy–relatedness, and masculinity mediated the relationship between culture and romantic relationship satisfaction. Additionally, as anticipated, Turkish participants scored lower on relationship satisfaction and autonomy whereas British participants scored lower...

  6. Utilisation of British University Research Reactors. (United States)

    Duncton, P. J.; And Others

    British experience relating to the employment of university research reactors and subcritical assemblies in the education of nuclear scientists and technologists, in the training of reactor operators and for fundamental pure and applied research in this field is reviewed. The facilities available in a number of British universities and the uses…

  7. British African Caribbean Women and Depression (United States)

    Adkison-Bradley, Carla; Maynard, Donna; Johnson, Phillip; Carter, Stephaney


    Depression is a common condition among women in the United Kingdom. However, little is known about the context of depression among British African Caribbean women. This article offers a preliminary discussion regarding issues and information pertaining to depression among British African Caribbean women. Characteristics and symptoms of depression…

  8. Indian Education Programs in British Columbia. (United States)

    Kelly, Reg

    The British North America Act of 1867, the founding constitution of Canada, provides that all matters pertaining to Indians and Indian lands are under Federal jurisdiction. Because of this, the province of British Columbia (BC) has not felt it could do much for native peoples and little attention has been paid to the extension of provincial…

  9. Fabrication of Wood-Rubber Composites Using Rubber Compound as a Bonding Agent Instead of Adhesives

    Directory of Open Access Journals (Sweden)

    Dongwei Shao


    Full Text Available Differing from the hot-pressing method in the manufacturing of traditional wood-rubber composites (WRCs, this study was aimed at fabricating WRCs using rubber processing to improve water resistance and mechanical properties. Three steps were used to make WRCs, namely, fiber-rubber mixing, tabletting, and the vulcanization molding process. Ninety-six WRC panels were made with wood fiber contents of 0%–50% at rotor rotational speeds of 15–45 rpm and filled coefficients of 0.55–0.75. Four regression equations, i.e., the tensile strength (Ts, elongation at break (Eb, hardness (Ha and rebound resilience (Rr as functions of fiber contents, rotational speed and filled coefficient, were derived and a nonlinear programming model were developed to obtain the optimum composite properties. Although the Ts, Eb and Rr of the panels were reduced, Ha was considerably increased by 17%–58% because of the wood fiber addition. Scanning electron microscope images indicated that fibers were well embedded in rubber matrix. The 24 h water absorption was only 1%–3%, which was much lower than commercial wood-based composites.

  10. Low surface energy rubber materials : relationship between network architecture and tack of silicone rubbers

    NARCIS (Netherlands)

    Mikrut, M.


    The objective of this work was to investigate the relationship between different factors characterizing the network structure on the tackiness of silicone rubber (PDMS). A custom tack testing device was constructed, based on the existing Tel-Tak principle. The experimental work involved testing the

  11. Natural rubber/nitrile butadiene rubber/hindered phenol composites with high-damping properties

    Directory of Open Access Journals (Sweden)

    Xiuying Zhao


    Full Text Available New natural rubber (NR/nitrile butadiene rubber (NBR/hindered phenol (AO-80 composites with high-damping properties were prepared in this study. The morphological, structural, and mechanical properties were characterized by atomic force microscopy (AFM, polarized Fourier transform infrared spectrometer (FTIR, dynamic mechanical thermal analyzer (DMTA, and a tensile tester. Each composite consisted of two phases: the NR phase and the NBR/AO-80 phase. There was partial compatibility between the NR phase and the NBR/AO-80 phase, and the NR/NBR/AO-80 (50/50/20 composite exhibited a co-continuous morphology. Strain-induced crystallization occurred in the NR phase at strains higher than 200%, and strain-induced orientation appeared in the NBR/AO-80 phase with the increase of strain from 100% to 500%. The composites had a special stress–strain behavior and mechanical properties because of the simultaneous strain-induced orientation and strain-induced crystallization. In the working temperature range of a seismic isolation bearing, the composites (especially the NR/NBR/AO-80 (50/50/20 composite presented a high loss factor, high area of loss peak (TA, and high hysteresis energy. Therefore, the NR/NBR/AO-80 rubber composites are expected to have important application as a high-performance damping material for rubber bearing.

  12. Penelitian penggunaan campuran karet alam RSS dengan stiren butadien rubber (SBR dalam pembuatan soft rubber lining

    Directory of Open Access Journals (Sweden)

    Penny Setyowati


    Full Text Available The objective of this research is to obtain optimum composition of RSS and SBR compound for making soft rubber lining compound. Based on seven combination of trials in compound formulation proved that formulation with composition of RSS 50 parts and SBR 50 parts give the best physical properties and highly cemented on steel by using “Desmodur R” adhesive solution.

  13. Kansei engineering as a tool for the design of in-vehicle rubber keypads. (United States)

    Vieira, Joana; Osório, Joana Maria A; Mouta, Sandra; Delgado, Pedro; Portinha, Aníbal; Meireles, José Filipe; Santos, Jorge Almeida


    Manufacturers are currently adopting a consumer-centered philosophy which poses the challenge of developing differentiating products in a context of constant innovation and competitiveness. To merge both function and experience in a product, it is necessary to understand customers' experience when interacting with interfaces. This paper describes the use of Kansei methodology as a tool to evaluate the subjective perception of rubber keypads. Participants evaluated eleven rubber keys with different values of force, stroke and snap ratio, according to seven Kansei words ranging from "pleasantness" to "clickiness". Evaluation data was collected using the semantic differential technique and compared with data from the physical properties of the keys. Kansei proved to be a robust method to evaluate the qualitative traits of products, and a new physical parameter for the tactile feel of "clickiness" is suggested, having obtained better results than the commonly used Snap Ratio. It was possible to establish very strong relations between Kansei words and all physical properties. This approach will result in guidance to the industry for the design of in-vehicle rubber keypads with user-centered concerns. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Elimination of the reactivation process in the adhesion of chlorinated SBS rubber with polychloroprene adhesives

    Directory of Open Access Journals (Sweden)


    Full Text Available Chlorination treatment of a thermoplastic styrene-butadiene-styrene rubber (SBS with a 3 wt% solution of trichloroisocyanuric acid (TCI in methyl ethyl ketone (MEK introduces chlorinated and oxidized moieties on the rubber surface which increase its surface energy and produces surface microroughness. Consequently adhesion properties, evaluated by T-peel strength measurements in chlorinated SBS/solvent based-polyurethane adhesive/leather joints, are enhanced. In this study, two solvent-based polychloroprene adhesives (PCP0 and PCP30R have been considered as an alternative to the commonly used solvent-based polyurethane adhesive (PU. A thermoreactive phenolic resin was added to one of the polychloroprene adhesive formulations (PCP30R. This tackifier resin favors chlorination of the adhesive and reinforces the interface between the chlorinated adhesive and the chlorinated rubber surface. Besides, PCP30R adhesive does not need adhesive reactivation and considerable high T-peel strength value (5.7±0.3 kN/m was obtained. Elimination of the reactivation process implies a considerable improvement of the manufacturing process in the footwear industry.

  15. Microstructure evolution and tribological properties of acrylonitrile-butadiene rubber surface modified by atmospheric plasma treatment (United States)

    Shen, Ming-xue; Zhang, Zhao-xiang; Peng, Xu-dong; Lin, Xiu-zhou


    For the purpose of prolonging the service life for rubber sealing elements, the frictional behavior of acrylonitrile-butadiene rubber (NBR) surface by dielectric barrier discharge plasma treatments was investigated in this paper. Surface microstructure and chemical composition were measured by atomic force microscopy, field-emission scanning electron microscopy, and X-ray photoelectron spectroscopy, respectively. Water contact angles of the modified rubber surface were also measured to evaluate the correlation between surface wettability and tribological properties. The results show that plasma treatments can improve the properties of the NBR against friction and wear effectively, the surface microstructure and roughness of plasma-modified NBR surface had an important influence on the surface tribological behavior, and the wear depth first decreased and then increased along with the change of plasma treatment time. It was found that the wettability of the modified surface was gradually improved, which was mainly due to the change of the chemical composition after the treatment. This study suggests that the plasma treatment could effectively improve the tribological properties of the NBR surface, and also provides information for developing wear-resistant NBR for industrial applications.

  16. Status report : British Columbia`s economic plan

    Energy Technology Data Exchange (ETDEWEB)



    A sector-by-sector update of actions taken under British Columbia`s three-year economic plan is outlined and the progress to date reviewed. The three year plan includes the support for industry growth in partnership with the private sector, making Vancouver a major international conference destination, and developing Vancouver International Airport into a major gateway to the Pacific. The plan also includes the promotion of adventure tourism in major international markets, and promoting aboriginal tourism and culture. The government also plans to stimulate the economy by providing $973 million in tax reductions for BC families and business. 1 tab.

  17. A Lass and a Lack? Women in British Silent Comedy


    Porter, Laraine


    This chapter considers the role of women in British silent film comedy from 1895 to the end of the 1920s and their legacy into the early sound period. It argues that women comedians became increasingly marginalized as cinema developed into an industry, with the codes, form and style of the “mature silent cinema” restricting women into a narrow range of stereotypes that negated female agency and prioritized looks and glamour over personality or character. The dominance of a few male directors ...

  18. Viscoelastic properties of short aramid fibres-reinforced rubbers

    NARCIS (Netherlands)

    Sadatshirazi, S.; Talma, Auke; Noordermeer, Jacobus W.M.


    Among short fiber-reinforced composites, those with rubber matrices have gained great importance due to the advantages they have in processing and low cost, coupled with high strength. These composites combine the elastic behavior of rubbers with strength and stiffness of fibers. Reinforcement with

  19. Evaluation of phosphorus status of some soils under estate rubber ...

    African Journals Online (AJOL)

    Evaluation of phosphorus status of some soils under estate rubber (Hevea Brasiliensis Muel. Agro.) trees in Southern Cross River State. EE Attoe, UC Amalu. Abstract. No abstract. Keywords: rubber tree; phosphorus uptake; soil P; leaf P; root mat P Global Journal of Agricultural Sciences Vol. 4(1) 2005: 55-61. Full Text:.

  20. 21 CFR 872.6300 - Rubber dam and accessories. (United States)


    ...) MEDICAL DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6300 Rubber dam and accessories. (a) Identification. A rubber dam and accessories is a device composed of a thin sheet of latex with a hole in the... cavity preparation. The device is stretched around a tooth by inserting a tooth through a hole in the...

  1. Electric pulse resistance of liquid nitrogen and rubber (United States)

    Kurets, V. I.; Tarakanovskii, É. N.; Filatov, G. P.


    We report the results of experimental investigations of the breakdown amplitudes of pulsed voltages applied to centimeter-thick layers of liquid nitrogen and various kinds of rubber at 77 K. We report the characteristics of pulses that will puncture rubber in liquid nitrogen.

  2. Profitability Analysis Of Natural Rubber Tapping In Southern Nigeria ...

    African Journals Online (AJOL)

    The study was a conducted to analyse cost and returns to rubber tapping in Southern Nigeria .Structured questionnaires were administered to a random sample of 129 tappers . Data collected were analysed using descriptive statistics and budgetary technique. The result indicated that males dominated rubber tapping, all of ...

  3. Effects of Dietary Substitution of Rubber Seed Cake for Groundnut ...

    African Journals Online (AJOL)

    Three hundred (300) five weeks old, Anak broilers were used in a 4-week experiment to determine the effect of dietary substitution of rubber seed cake for groundnut cake on the performance of broilers at the finisher phase. Graded levels of rubber seed cake (0, 25, 50, 75 and 100%) substituted corresponding levels of ...

  4. Replacement of groundnut cake with rubber ( Hevea brasiliensis ...

    African Journals Online (AJOL)

    This study was carried out to determine the level of rubber seed cake (RSC) that could be used to replace groundnut cake (GNC) in practical diets of Oreochromis niloticus. RSC, a by-product of the oil extraction of the rubber tree seed and GNC were interchangeably replaced in the formulation of five experimental diets fed ...

  5. Constraints to rubber production in Sapele local government area of ...

    African Journals Online (AJOL)

    The study investigated among other things the constraints to rubber production in Sapele Local Government Area of Delta State, Nigeria. One hundred and twenty rubber farmers randomly selected from twelve villages in the Local Government Area were used to constitute the sample. Stratified and random sampling was ...

  6. Adaptation of the rubber bandage for safe use as tourniquet ...

    African Journals Online (AJOL)

    The safety of the pneumatic tourniquet lies in the fact that the pressure generated beneath it can be determined and is reproducible unlike the rubber bandage tourniquet with subjective and irreproducible tissue pressure. Application of the rubber bandage over the cuff of an aneroid sphygmomanometer enabled direct ...

  7. Differential responses of two rubber tree clones to chilling stress ...

    African Journals Online (AJOL)

    Chilling stress is one of the most important environmental factors that limit the growth, distribution and yield of rubber tree in China. The effects of chilling stress on the grated plants of two rubber trees clones, GT1 and Wenchang217, were studied by physiological methods in controlled light chamber in order to explore the ...

  8. Influence of Plasma Treatments on the Frictional Performance of Rubbers

    NARCIS (Netherlands)

    Wolthuizen, D.J.; Martinez-Martinez, D.; Pei, Y.T.; Hosson, J.Th.M. De

    The frictional performance of several rubbers after pulsed-DC plasma treatments has been examined. In all cases, the treated rubbers showed better performance than the corresponding untreated ones. Stronger treatments, in terms of longer process time and/or higher substrate bias voltage, led to

  9. Natural Rubber Quantification in Sunflower Using an Automated Solvent Extractor (United States)

    Leaves of sunflower (Helianthus annuus) produce a small amount of low molecular weight natural rubber (NR) and this species has potential as a rubber-producing crop plant. Quantifying NR in plant tissue has traditionally been accomplished using Soxhlet or gravimetric methodologies. Accelerated solve...

  10. Ground tire rubber as a stabilizer for subgrade soils : [summary]. (United States)


    Over 250 million scrap tires are generated : annually in the U.S. Historically, a significant : portion of these tires have been processed into : finely ground tire rubber (GTR), or crumb rubber, : for use as an additive in hot mix asphalt (HMA) : pa...

  11. Ground tire rubber as a stabilizer for subgrade soils. (United States)


    Over 250 million scrap tires are generated annually in the U.S. Historically, a significant portion of these tires : have been processed into finely ground tire rubber (GTR), or crumb rubber, for use as an additive in hot mix asphalt : (HMA) pavement...

  12. Research and Application Progress of Silicone Rubber Materials in Aviation

    Directory of Open Access Journals (Sweden)

    HUANG Yanhua


    Full Text Available The research progress of heat resistance, cold resistance, electrical conductivity and damping properties of aviation silicone rubber were reviewed in this article. The heat resistance properties of silicone rubber can be enhanced by changing the molecular structure (main chain, end-group, side chain and molecular weight of the gum and adding special heat-resistance filler. The cold resistance of aviation silicone rubber can be enhanced by adjusting the side chain molecular structure of the gum and the content of different gum chain. The electrical conductivity of silicone rubber can be improved by optimizing, blending and dispersing of conductive particles. The damping property of silicone rubber can be improved by designing and synthesizing of high-molecular polysiloxane damping agent. Furthermore, the application of aviation silicone rubber used in high-low temperature seal, electrical conduction and vibration damping technology are also summarized, and the high performance (for example long-term high temperature resistance, ultralow temperature resistance, high electromagnetic shelding, long-term fatigue resistance vibration damping, quasi constant modulus and so on of special silicone rubber is the future direction of aviation silicone rubber.

  13. Rubber composites cured with sulphur and peroxide and ...

    Indian Academy of Sciences (India)

    Besides classical applications of rubber products in tyres, conveyer belts and other products from technical rubber, ... application of sulphur curing systems leads to the forming of sulphidic bridges with various number of ... have advantages but also drawbacks, the main aim was to suppress the main negatives of both curing ...

  14. Guayule resin detection and influence on guayule rubber (United States)

    Guayule (Parthenium argentatum) is a natural rubber (cis-1,4-polyisoprene) producing crop, native to North America. Guayule also produces organic resins, complex mixtures of terpenes, triglycerides, guayulins, triterpenoids and other components. During natural rubber extraction, guayule resins can b...

  15. Reinforcement Effect of Corn Flour in Rubber Composites (United States)

    Corn flour is an economical renewable material and investigated in this study as filler for rubber composites. The composites were prepared by mixing an aqueous dispersion of corn flour with rubber latex, followed by freeze-drying and compression molding. The small strain elastic modulus and the str...

  16. Rubber Flooring Impact on Production and Herdlife of Dairy Cows (United States)

    Use of rubber flooring in dairies has become popular because of perceived cow comfort. The overall objective of this longitudinal study was to evaluate production, reproduction, and retention of first and second lactations of cows assigned to either rubber (RUB) or concrete (CON) flooring at the fe...

  17. Polyacrylamide brush coatings preventing microbial adhesion to silicone rubber

    NARCIS (Netherlands)

    Fundeanu, Irina; van der Mei, Henny C.; Schouten, Arend J.; Busscher, Henk J.


    Silicone rubber is a frequently used biomaterial in biomedical devices and implants, yet highly prone to microbial adhesion and the development of a biomaterial-centered infection. Effective coating of silicone rubber to discourage microbial adhesion has thus far been impossible due to the

  18. Screening ten genotypes of natural rubber seedlings ( Hevea ...

    African Journals Online (AJOL)

    A field study was conducted in 2012 and 2013 cropping season at the Research Farm of National Root Crops Research Institute, (NRCRI) Umudike, in Abia State, to screen 10 rubber genotypes collected from Rubber Research Institute of Nigeria for tolerant to drought conditions. The aim was to select tolerant genotypes for ...


    African Journals Online (AJOL)

    POLYVINYL CHLORIDE AGAINST THERMAL DEGRADATION. F.E. Okieimen. Department of Chemistry, University of Benin, Benin City, Nigeria. ABSTRACT. Thermal degradation studies on polyvinyl chloride in the presence of rubber seed oil, epoxidized rubber seed oil and metal soaps (barium, cadmium and lead) of the ...

  20. Blends of guayule natural rubber latex with commercial latex polymers (United States)

    Guayule (Parthenium argentatum) is a woody desert shrub that produces natural rubber, cis-1,4 polyisoprene, by biosynthesis. It is currently cultivated in the southwestern United States as a source of latex and rubber for commercial development. Guayule latex is similar to Hevea latex in polymer mo...

  1. Implication of Climate Variability for Latex Exudates F Rubber Tree ...

    African Journals Online (AJOL)

    The study aimed at: assessing the relationship between latex exudates and climate variability; identifying the most critical climate element(s) in the yield variability of rubber; and examining the predictability of rubber yield based on climate variability. Fifteen years data was collected from documented, but unpublished, ...

  2. Reinforcement of latex rubber by the incorporation of amphiphilic particles (United States)

    Latex rubbers are fabricated from latex suspensions. During the fabrication process, latex particles are bound together while water is removed from the suspension. This report shows that the mechanical properties of latex rubbers can be improved by incorporating a small amount of amphiphilic submicr...

  3. minimum variance estimation of yield parameters of rubber tree

    African Journals Online (AJOL)


    Mar 1, 2013 ... raw material supply chain and hence marketing plan. The result matches the wet and dry spell of southern. Nigeria and its effect on rubber tree latex production. The seasonal value by quarter is estimated for each clone to be used for appropriate quarterly adjustment in the aggregate rubber production ...

  4. Characterization of weed flora in rubber trees plantations of Bongo ...

    African Journals Online (AJOL)

    Objectives: the main objective of this study is to characterize the weed floristic diversity of the Bongo rubber trees plantation and to provide a map for sustainable weed management. Methodology and results: a floristic survey of the Para rubber plantations of Bongo (Southeast Côte d'Ivoire) was conducted in 2007 and early ...

  5. Demotivating factors influencing rubber production workers

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Iravani


    Full Text Available Motivation is one of the most important factors influencing workers' productivity. An increase in workers' motivation could add more value to organizations' structure and influence the profitability, significantly. In this paper, we study different factors on demotivating workers using questionnaire consist of various questions. The questionnaire is distributed among some employees who work for rubber production units located in Esfahan, Iran. The results of this survey indicate that discrimination on annual job compensation, entrusting responsibilities and unpleasant relationship with family partner are some of the most important factors influencing employees' motivation. While financial factors play important role on increasing employees' motivation, non-financial factors are considered more important.

  6. Hacking Experiment Using USB Rubber Ducky Scripting

    Directory of Open Access Journals (Sweden)

    Benjamin Cannoles


    Full Text Available By leaving your computer unlocked while you are away for seconds can give hackers all the time they need to obtain your personal information from your computer. This paper aims to detail the necessary research and development of a USB Rubber Ducky script, to obtain clear text logon id and passwords from a Windows machine, in mere seconds. Each stage is laid out in sections discussing Ducky script, powershell, Mimikatz, and reenabling the vulnerability by breaking down the attack into two parts for Windows 7 and up operating systems.

  7. Viscoelastic modeling of filled, crosslinked rubbers (United States)

    Joshi, Prashant G.


    Filled polymer systems have been a subject of interest for rheologists since the past many decades. Their applications range from paints and pigments to high performance composite materials. Tires come under a special class of applications wherein the type of filler used, its reinforcing abilities, traction improvement capabilities and cost effectiveness enormously control the final end use. Presently, there is lack of a complete understanding of the behavior of these materials under different load conditions. Moreover there is a lack of a comprehensive theory which can describe the rheology of filled rubbers, their chemorheology, and their behavior in the final fully cured state simultaneously. The present work is aimed at capturing a wide range of rheological/viscoelastic properties of filled rubbers with one set of constitutive/kinetic equations and a flexible relaxation spectrum. Various mechanical properties of filled, crosslinked rubbers were investigated in order to understand their analogy in the melt state. For this purpose, quasi-static hysteresis and step-strain relaxation experiments were carried out. Dynamic mechanical properties were understood in great details by using Fourier harmonic analysis to understand the time and strain non-linearities in the material. The time non-linearities arise due to thixotropic and non-isothermal effects, while the waveform distortions (strain related) occur due to non-linear viscoelastic effects. It is also very important to ensure no interference from any extraneous noise in the system during a dynamic test. Using the experimental evidences in melt rheology (creeping flow, shear start-up, and relaxation), and the kinetic mechanisms that affect chemorheology [152], an appropriate thixotropic-viscoelastic spectrum was chosen in order to describe experiments in all states of SBR rubber satisfactorily. This approach convinces that various manifestations of the filler in the melt state are preserved during crosslinking

  8. A Micro-Mechanically Based Continuum Model for Strain-Induced Crystallization in Natural Rubber (United States)

    Mistry, Sunny Jigger

    Recent experimental results show that strain-induced crystallization can substantially improve the crack growth resistance of natural rubber. While this might suggest superior designs of tires or other industrial applications where elastomers are used, a more thorough understanding of the underlying physics of strain-induced crystallization in natural rubber has to be developed before any design process can be started. The objective of this work is to develop a computationally-accessible micro-mechanically based continuum model, which is able to predict the macroscopic behavior of strain crystallizing natural rubber. While several researchers have developed micro-mechanical models of partially crystallized polymer chains, their results mainly give qualitative agreement with experimental data due to a lack of good micro-macro transition theories or the lack of computational power. However, recent developments in multiscale modeling in polymers provide new tools to continue this early work. In this thesis, a new model is proposed to model strain-induced crystallization in natural rubber. To this end, a micro-mechanical model of a constrained partially crystallized polymer chain with an extended-chain crystal is derived and connected to the macroscopic level using the non-affine micro-sphere model. On the macroscopic level, a thermodynamically consistent framework for strain-crystallizing materials is developed, and a description of the crystallization kinetics is introduced. For that matter, an evolution law for crystallization based on the gradient of the macroscopic Helmholtz free energy function (chemical potential) in combination with a simple threshold function is used. A numerical implementation of the model is proposed and its predictive performance assessed using published data.

  9. New type of liquid rubber and compositions based on it. (United States)

    Semikolenov, S V; Nartova, A V; Voronchikhin, V D; Dubkov, K A


    The new method for producing the functionalized polymers and oligomers containing carbonyl C=O groups is developed. The method is based on the noncatalytic oxidation of unsaturated rubbers by nitrous oxide (N2O) at 180-230 °С. The proposed method allows obtaining the new type of functionalized rubbers-liquid unsaturated polyketones with regulated molecular weight and concentration of C=O groups. The influence of the liquid polyketone addition on properties of rubber-based composites is investigated. The study indicates good prospects of using the liquid polyketones for the improvement of properties and operating characteristics of the various types of rubbers and the rubber-cord systems.

  10. Statistical Discrimination of Latex between Healthy and White Root Infected Rubber Tree based on Dry Rubber Content (United States)

    Suhaimi Sulaiman, Mohd; Hashim, Hadzli; Faiz Mohd Sampian, Ahmad; Korlina Madzhi, Nina; Faris Mohd Azmi, Azrie; Aishah Khairuzzaman, Noor; Aima Ismail, Faridatul


    Dry rubber content (DRC) is one of main material existing inside latex. It is usually in ranged of 25% - 45% of rubber latex. Statistical analysis are done to determine the discrimination of dry rubber content of latex between healthy and white root infected rubber tree. Based on 150 rubber trees and 10 clones tested, parametric test which include normality test, error-bar plot, and paired samples test are done. The result outcomes have shown that both data of dry rubber content of latex for healthy and white root infected rubber tree are normally distributed. Error-bar plot test is clearly indicated that there is visible discrimination between both cases. Paired samples test are done to reinforce this findings in terms of numerical p- value which is found to be less than 0.05. Thus, this indicate overwhelming evidence that healthy group can be discriminated from white root. Conclusively, changes in DRC content in latex can be correlated with white root disease infections of rubber tree.

  11. [Mites (Acari) from rubber trees (Hevea brasiliensis Muell. Arg., Euphorbiaceae) and spontaneous euphorbiaceous in rubber trees cultivation]. (United States)

    Bellini, Marcos R; Feres, Reinaldo J F; Buosi, Renato


    Quarterly samples were done in 2001 on three rubber tree plantation in the northwest of the state of São Paulo. Three rubber trees of each locality were sampled. Between the rows of rubber tree four species of spontaneous euphorbiaceous were collected: Chamaesyce hirta, C. hyssopifolia, Euphorbia heterophylla and Phyllanthus tenellus. A total of 8.954 mites of 38 species, belonging to 31 genera of 11 families were collected. Tydeidae and Phytoseiidae had the highest diversity of species, 9 and 7, respectively. The most abundant families were Eriophyidae (3.594), Tydeidae (2.825) and Tenuipalpidae (1.027). The most abundant species on the rubber trees were: phytophagous - Calacarus heveae Feres, Tenuipalpus heveae Baker, Lorryia sp.2, Lorryia formosa Cooreman and Lorryia sp.1; predators - Zetzellia quasagistemas Hernandes & Feres, Pronematus sp., Iphiseiodes zuluagai Denmark & Muma and Euseius citrifolius Denmark & Muma. Among the spontaneous euphorbiaceous, predatory mites were abundantly found on C. hirta and E. heterophylla, mainly Pronematus sp. and E. citrifolius, suggesting that these plants could be important in the maintenance of these predators in the rubber tree cultivation areas. However, plants that can shelter predators and at the same time exert strong competition (nutrients, water etc) to rubber trees, can not be recommended for pest management programs. Studies about competition between rubber trees and spontaneous plants need to be conducted for feasible efficient programs of environmental management, aiming at the control of pest mites of rubber tree.

  12. Nylon-6/rubber blends: 6. Notched tensile impact testing of nylon-6(ethylene-propylene rubber) blends

    NARCIS (Netherlands)

    Dijkstra, Krijn; Dijkstra, K.; ter Laak, J.A.; ter Laak, J.; Gaymans, R.J.


    The deformation and fracture behaviour of nylon-6/EPR (ethylene-propylene rubber) blends is studied as a function of strain rate and rubber content. Therefore, tensile experiments are conducted on notched specimens over a broad range of draw speeds (including strain rates as encountered in normal

  13. Reinforcing effect of plasma modified halloysite nanotubes in a carbon black filled natural rubber-butadien rubber matrix

    NARCIS (Netherlands)

    Poikelispaa, Minna; Das, Amit; Dierkes, Wilma K.; Vuorinen, Jyrki


    Rubber composites are generally produced by the direct incorporation of fillers like carbon black and/or silica into the rubber matrix. The incorporation of different types of nanofillers is the subject of recent research with the aim of preparing composites with special compositions and properties.

  14. Recycling of rubber tires in electric arc furnace steelmaking: simultaneous combustion of metallurgical coke and rubber tyres blends

    Energy Technology Data Exchange (ETDEWEB)

    Magdalena Zaharia; Veena Sahajwalla; Byong-Chul Kim; Rita Khanna; N. Saha-Chaudhury; Paul O' Kane; Jonathan Dicker; Catherine Skidmore; David Knights [University of New South Wales, Sydney, NSW (Australia). School of Materials Science and Engineering


    The present study investigates the effect of addition of waste rubber tires on the combustion behavior of its blends with coke for carbon injection in electric arc furnace steelmaking. Waste rubber tires were mixed in different proportions with metallurgical coke (MC) (10:90, 20:80, 30:70) for combustion and pyrolysis at 1473 K in a drop tube furnace (DTF) and thermogravimetric analyzer (TGA), respectively. Under experimental conditions most of the rubber blends indicated higher combustion efficiencies compared to those of the constituent coke. In the early stage of combustion the weight loss rate of the blends is much faster compared to that of the raw coke due to the higher volatile yield of rubber. The presence of rubber in the blends may have had an impact upon the structure during the release and combustion of their high volatile matter (VM) and hence increased char burnout. Measurements of micropore surface area and bulk density of the chars collected after combustion support the higher combustion efficiency of the blends in comparison to coke alone. The surface morphology of the 30% rubber blend revealed pores in the residual char that might be attributed to volatile evolution during high temperature reaction in oxygen atmosphere. Physical properties and VM appear to have a major effect upon the measured combustion efficiency of rubber blends. The study demonstrates that waste rubber tires can be successfully co-injected with metallurgical coke in electric arc furnace steelmaking process to provide additional energy from combustion. 44 refs., 11 figs., 2 tabs.

  15. Accelerated lifetime test of vibration isolator made of Metal Rubber material (United States)

    Ao, Hongrui; Ma, Yong; Wang, Xianbiao; Chen, Jianye; Jiang, Hongyuan


    The Metal Rubber material (MR) is a kind of material with nonlinear damping characteristics for its application in the field of aerospace, petrochemical industry and so on. The study on the lifetime of MR material is impendent to its application in engineering. Based on the dynamic characteristic of MR, the accelerated lifetime experiments of vibration isolators made of MR working under random vibration load were conducted. The effects of structural parameters of MR components on the lifetime of isolators were studied and modelled with the fitting curves of degradation data. The lifetime prediction methods were proposed based on the models.

  16. Factors Affecting the Adsorption of Trivalent Chromium Ions by Activated Carbon Prepared from Waste Rubber Tyres

    Directory of Open Access Journals (Sweden)

    Sylvia E. Benjamin


    Full Text Available Economic gains are generally the outcome of industrialization and consequently urbanization. However, positive fiscal index generates a negative impact on natural environment sources heaving pollutant burden on soil, air and water. Industries throw tones of contaminated water into soil and water bodies without proper treatment and create a potential threat for both living and non-living species. Chromium in trivalent state (Cr3+ is added in water bodies and soil through waste water from tanneries, cooling water systems, chemical and pulp and paper industries. The present research work aims at the preparation of an inexpensive activated carbon prepared from non- degradable waste scrap rubber tyres. The carbon produced from scrap rubber tyres was activated by 5% solution of BaCl2 and 0.4 N solution of HCl and verified by ethylene blue solution. The adsorption capacity of the Tyre activated carbon (TAC was investigated for different parameters i.e., initial chromium (III ion concentration, activated carbon dosage, contact/ stirring time and pH. The adsorption capacity of TAC depends on the initial metal ion concentration and the TAC dose. pH of the chromium solution effects the adsorption capacity of TAC due to the formation of tetra hydroxochromate(III complexes,. The results show that TAC offers a cost effective reclamation process for the removal of Cr3+ from effluent waters.

  17. Multiscale physics of rubber-ice friction (United States)

    Tuononen, Ari J.; Kriston, András; Persson, Bo


    Ice friction plays an important role in many engineering applications, e.g., tires on icy roads, ice breaker ship motion, or winter sports equipment. Although numerous experiments have already been performed to understand the effect of various conditions on ice friction, to reveal the fundamental frictional mechanisms is still a challenging task. This study uses in situ white light interferometry to analyze ice surface topography during linear friction testing with a rubber slider. The method helps to provide an understanding of the link between changes in the surface topography and the friction coefficient through direct visualization and quantitative measurement of the morphologies of the ice surface at different length scales. Besides surface polishing and scratching, it was found that ice melts locally even after one sweep showing the refrozen droplets. A multi-scale rubber friction theory was also applied to study the contribution of viscoelasticity to the total friction coefficient, which showed a significant level with respect to the smoothness of the ice; furthermore, the theory also confirmed the possibility of local ice melting.

  18. Synthesis biolubricant from rubber seed oil (United States)

    Hung, Nguyen Tran Dong; Tuyen, Dang Thi Hong; Viet, Tran Tan


    The objective was biolubricant preparation from rubber seed oil (RSO) using polymerization reactor with/without catalyst in batch reactor. Before become reactant in polymerization reaction, a non-edible rubber seed oil was converted into methyl ester by esterification/tranesterification reaction with methanol and acid/base catalyst. The polymerization reaction parameters investigated were reaction time, temperature and weight ratio (catalyst with feed), and their effect on the bio lubricant formation. The result show significant conversion of methyl ester to bio lubricant in the temperature reaction of 160°C, reaction time of 2h min and ratio of super acid catalyst (tetrafluoroboric acid-sHBF4) of 3 %w/w. The resulting products were confirmed by GC-MS, FTIR spectroscopy and also analyzed for the viscosity. The best viscosity value of RSOFAME polymer was 110.6 cSt when the condition polymerization reaction were 160 °C, reaction time 3h, 6 wt% mass ratio of oil:catalyst.

  19. Making sense of the labor market height premium: Evidence from the British Household Panel Survey. (United States)

    Case, Anne; Paxson, Christina; Islam, Mahnaz


    We use data from the British Household Panel Survey to examine the labor market premium in height. Most of the premium is explained by higher average educational attainment and sorting into higher-status occupations and industries by those who are taller.

  20. Censuses compared. A New Benchmark for British and German Manufacturing 1935/1936

    NARCIS (Netherlands)

    Fremdling, Rainer; Jong, Herman de; Timmer, Marcel P.


    We present a new estimate of Anglo-German manufacturing output and productivity levels by industry for 1935/36. It is based on newly explored archival data on German manufacturing together with published British census data. We calculate comparative levels of value added, correcting for differences

  1. Social Media as Beat : Tweets as a news source during the 2010 British and Dutch elections

    NARCIS (Netherlands)

    Broersma, M.J.; Graham, T.S.


    While the newspaper industry is in crisis and less time and resources are available for newsgathering, social media turn out to be a convenient and cheap beat for (political) journalism. This article investigates the use of Twitter as a source for newspaper coverage of the 2010 British and Dutch

  2. Progress in Characterizing Thermal Degradation of Ethylene-Propylene Rubber

    Energy Technology Data Exchange (ETDEWEB)

    Fifield, Leonard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Huang, Qian [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Childers, Matthew I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Correa, Miguel [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Shin, Yongsoon [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zwoster, Andy [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)


    Ethylene-propylene rubber (EPR) is one of the two most common nuclear cable insulation materials. A large fraction of EPR-insulated cables in use in the nuclear industry were manufactured by The Okonite Company. Okoguard® is the name of the medium voltage thermoset EPR manufactured by The Okonite Company. Okoguard® has been produced with silane-treated clay filler and the characteristic pink color since the 1970’s. EPR is complex material that undergoes simultaneous reactions during thermal aging including oxidative and thermal cleavage and oxidative and thermal crosslinking. This reaction complexity makes precise EPR service life prediction from accelerated aging using approaches designed for single discreet reactions such as the Arrhenius approach problematic. Performance data and activation energies for EPR aged at conditions closer to service conditions will improve EPR lifetime prediction. In this report pink Okoguard® EPR insulation material has been thermally aged at elevated temperatures. A variety of characterization techniques have been employed to track material changes with aging. It was noted that EPR aged significant departure in aging behavior seemed to occur at accelerated aging temperatures between 140°C and 150°C at around 20 days of exposure. This may be due to alternative degradation mechanisms being accessed at this higher temperature and reinforces the need to perform accelerated aging for Okoguard® EPR service life prediction at temperatures below 150°C.

  3. 40 CFR 428.30 - Applicability; description of the solution crumb rubber subcategory. (United States)


    ... solution crumb rubber subcategory. 428.30 Section 428.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS RUBBER MANUFACTURING POINT SOURCE CATEGORY Solution Crumb Rubber Subcategory § 428.30 Applicability; description of the solution crumb rubber subcategory...

  4. 40 CFR 428.20 - Applicability; description of the emulsion crumb rubber subcategory. (United States)


    ... emulsion crumb rubber subcategory. 428.20 Section 428.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS RUBBER MANUFACTURING POINT SOURCE CATEGORY Emulsion Crumb Rubber Subcategory § 428.20 Applicability; description of the emulsion crumb rubber subcategory...

  5. 21 CFR 177.1480 - Nitrile rubber modified acrylonitrile-methyl acrylate copolymers. (United States)


    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Nitrile rubber modified acrylonitrile-methyl... Nitrile rubber modified acrylonitrile-methyl acrylate copolymers. Nitrile rubber modified acrylonitrile... rubber modified acrylonitrile-methyl acrylate copolymers consist of basic copolymers produced by the...

  6. 75 FR 51981 - Polychloroprene Rubber from Japan: Final Results of Sunset Review and Revocation of Finding (United States)


    ... International Trade Administration Polychloroprene Rubber from Japan: Final Results of Sunset Review and... review of the antidumping finding on polychloroprene rubber from Japan. Because the domestic interested... polychloroprene rubber from Japan. See Polychloroprene Rubber from Japan, 38 FR 33593 (December 6, 1973). On...

  7. 21 CFR 801.437 - User labeling for devices that contain natural rubber. (United States)


    ... rubber. 801.437 Section 801.437 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... User labeling for devices that contain natural rubber. (a) Data in the Medical Device Reporting System..., natural rubber that contacts humans. The term “natural rubber” includes natural rubber latex, dry natural...

  8. 40 CFR 428.40 - Applicability; description of the latex rubber subcategory. (United States)


    ... latex rubber subcategory. 428.40 Section 428.40 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS RUBBER MANUFACTURING POINT SOURCE CATEGORY Latex Rubber Subcategory § 428.40 Applicability; description of the latex rubber subcategory. The provisions of...

  9. Particle reinforced composites from acrylamide modified blend of styrene-butadiene and natural rubber (United States)

    Blends of styrene-butadiene rubber and natural rubber that provide balanced properties were modified with acrylamide and reinforced with soy protein particles. The rubber composites show improved mechanical properties. Both modified rubber and composites showed a faster curing rate. The crosslinking...

  10. Plant and bird diversity in rubber agroforests in the lowlands of Sumatra, Indonesia

    NARCIS (Netherlands)

    Beukema, Hendrien; Danielsen, Finn; Vincent, Gregoire; Hardiwinoto, Suryo; van Andel, Jelte

    Plant and bird diversity in the Indonesian jungle rubber agroforestry system was compared to that in primary forest and rubber plantations by integrating new and existing data from a lowland rain forest area in Sumatra. Jungle rubber gardens are low-input rubber (Hevea brasiliensis) agroforests that

  11. Reinforcement effect of soy protein nanoparticles in amine-modified natural rubber latex (United States)

    Mechanical properties of natural rubber reinforced with soy protein nanoparticles are useful for various rubber applications. However, the properties is further improved by improving interactions between soy protein and rubber. A novel method is used to modify particle surface of natural rubber late...

  12. Practical application of thermoreversibly Cross-linked rubber products (United States)

    Polgar, L. M.; Picchioni, F.; de Ruiter, E.; van Duin, M.


    Currently, rubber products cannot simply be reprocessed after their product life, due to the irreversible cross-linking methods traditionally applied. The purpose of this work is to investigate how thermoreversible cross-linking of rubbers via Diels Alder chemistry can be used for the development of recyclable rubber products. Unfortunately, the applicability of the thermoreversible EPM-g-furan/BM system appears to be limited to room temperature applications, because of the rapid deterioration of the compression set at elevated temperatures compared to irreversibly cross-linked EPM. However, the use of EPM rubber modified with thiophene or cyclopentadiene moieties may extend the temperature application range and results in rubber products with acceptable properties. Finally, rubber products generally comprise fillers such as silica, carbon black or fibers. In this context, the reinforcing effect of short cut aramid fibers on the material properties of the newly developed thermoreversibly cross-linked EPM rubbers was also studied. The material properties of the resulting products were found to be comparable to those of a fiber reinforced, peroxide cured reference sample.

  13. The optimum content of rubber ash in concrete: flexural strength (United States)

    Senin, M. S.; Shahidan, S.; Shamsuddin, S. M.; Ariffin, S. F. A.; Othman, N. H.; Rahman, R.; Khalid, F. S.; Nazri, F. M.


    Discarded scrap tyres have become one of the major environmental problems nowadays. Several studies have been carried out to reuse waste tires as an additive or sand replacement in concrete with appropriate percentages of tire rubber, called as rubberized concrete to solve this problem. The main objectives of this study are to investigate the flexural strength performance of concrete when adding the rubber ash and also to analyse the optimum content of rubber ash in concrete prisms. The performance total of 30 number of concrete prisms in size of 100mm x 100mm x 500 mm were investigated, by partially replacement of rubber ash with percentage of 0%, 3%, 5%, 7% and 9% from the volume of the sand. The flexural strength is increased when percentage of rubber ash is added 3% from control concrete prism, RA 0 for both concrete prism age, 7 days and 28 days with value 1.21% and 0.976% respectively. However, for RA 5, RA 7 and RA 9, the flexural strength was decreased compared to the control for both age, 7 days and 28 days. In conclusion, 3% is the optimum content of rubber ash in concrete prism for both concrete age

  14. Volume Changes in Filled Rubber Under Uniaxial Cyclic Loading

    Directory of Open Access Journals (Sweden)

    Elina KAZINA


    Full Text Available Styrene-butadiene rubber, neat and filled with different silica content was investigated under uniaxial cyclic loading under a constant crosshead speed, with increasing deformation amplitude in subsequent loading cycles. Rubber was investigated in order to evaluate the reversibility of structure rearrangements, occurring in rubber when subjected to cyclic loading. Volume uniformly increases with growing strain and shows hysteresis at unloading. After complete unloading, no residual strain changes are observed. These data are in good conformity with the data of density measurements, which were made on specimens before and after the tests. By correlating data, obtained from volume changes and kinetics of hysteresis losses there were made assumptions on deformation mechanisms at different elongations. Deformational mechanisms, responsible for volume changes in rubber are reversible. Volume changes in specimen occur due to voids formation caused by filler microstructure breakage, rubber chains disentanglement, spaces between rubber macromolecular chains shrinkage, and chain slippage under higher elongations. Voids formation and deformation of rubber macromolecular chain reaches equilibrium state after certain elongation.

  15. Fabrication of shape memory natural rubber using palmitic acid

    Directory of Open Access Journals (Sweden)

    Jeff Sze-Hua Wee


    Full Text Available This paper investigates the practicability of fabricating a shape memory natural rubber with the use of palmitic acid as the swelling agent. Strips of natural rubber samples were swollen in molten palmitic acid at 75 °C. Equilibrium swelling of natural rubber with palmitic acid was found to occur at approximately 50 min of swelling time. Under cooling effect, the palmitic acid crystallized to form a percolated crystalline platelet network. These networks allow fabricated shape memory natural rubber (SMNR to deform and recover its shape at a temperature above the melting point of palmitic acid. Under controlled uniaxial stress, the natural rubber sample with 0 parts per hundred rubber (phr carbon black loading exhibits fixity and recovery of 80 ± 10%. Motivation of this research is primarily on practicability of palmitic acid to be used as a swelling agent for shape memory properties. Results show that palmitic acid is a relatively good swelling agent to induce shape memory properties into natural rubber.

  16. their use as Accelerator in Curing Process of Rubber Compounds

    Directory of Open Access Journals (Sweden)

    S. taghvaee


    Full Text Available In some special cases, rubber compounds with high amounts of unsaturated elastomer are recommended with organic sulfur donors instead of mineral sulfurs. In this condition, activated sulfur is produced in situ and curingprocess is facilitated without accelerators. Organic sulfur donor compounds have low thermal stability and in the vulcanization temperature produce free and activated sulfurs. The advantages of these compounds are:1. High effectiveness of curing agent in low quantities in rubber compounds manufacturing.2. Producing activated sulfurs in controlled condition and avoiding the over curing of rubber compounds.In this report the novel synthesis of some derivatives of diamino-disulfides which can be applied as sulfur donors in vulcanization of special rubber compounds is introduced. The key process is reaction of sulfurmonochloride with amines in petroleum ether as solvent in low temperature. Dithio-dimorpholine(DTDM, dithio-dipipyridyl (DTDP, dithio-bis dibutylamine (DTBDB and dithio-bisdiisopropyl amine (DTBDI were prepared according to this method. All products thus obtained were characterized by 1H and 13C-NMR spectroscopies. The effects of accelerating and sulfur donoring of all prepared agents were detected in rubber compounds with natural and synthetic rubber bases. All physical, chemical, reological and mechanical properties of rubber compounds based on prepared sulfur donors were characterized.

  17. Mechanical properties and durability of crumb rubber concrete (United States)

    Chylík, Roman; Trtík, Tomáš; Fládr, Josef; Bílý, Petr


    This paper is focused on concrete with admixture of rubber powder, generally called crumb rubber concrete (CRC). The inspiration was found in Arizona, where one of the first CRCs has been created. However, Arizona has completely different climates than Central Europe. Could we use the crumb rubber concrete on construction applications in the Central European climate too? The paper evaluates the influence of the rubber powder on material characteristics and durability of CRC. CRCs with various contents of fine and coarse crumb powder were compared. The tested parameters were slump, air content, permeability, resistance of concrete to water with deicing chemicals, compressive and splitting tensile strength. The tests showed that workability, compressive strength and permeability decreased as the amount of rubber increased, but the air content increased as the rubber content increased. Photos of air voids in cement matrix from electron microscope were captured. The results of laboratory tests showed that admixture of rubber powder in concrete could have a positive impact on durability of concrete and concurrently contribute to sustainable development. Considering the lower compressive strength, CRC is recommended for use in applications where the high strength of concrete is not required.

  18. Libraries in British Columbia: MedlinePlus (United States)

    ... this page: Libraries in British Columbia To use the sharing features ... George University Hospital of Northern BC Northern Health Library Services Learning & Development Centre 1475 Edmonton Street Prince ...

  19. British and American attitudes toward credit cards. (United States)

    Yang, Bijou; James, Simon; Lester, David


    American university students owned more than twice as many credit cards as British university students. However, scores on a credit card attitude scale predicted the number of cards owned by respondents in both countries.

  20. Retrenchment in British Universities: Lessons Learned. (United States)

    Simpson, William A.


    A study of 14 British universities that underwent severe retrenchment in 1981-1984 is reported, and successful policies, procedures, philosophies, and techniques that may be applicable to institutions in many countries are outlined. (MSE)

  1. Politics, policy and government in British Columbia

    National Research Council Canada - National Science Library

    Carty, R. Kenneth


    ... and Gerry Kristiansonvi Contents Part 3: Governing the Province 9 The Government of the Day: The Premier and Cabinet in British Columbia / 143 Terence Morley 10 Provincial Governance and the Pu...

  2. Model fire tests on polyphosphazene rubber and polyvinyl chloride (PVC)/nitrile rubber foams (United States)

    Widenor, W. M.


    A video tape record of model room fire tests was shown, comparing polyphosphazene (P-N) rubber and polyvinyl chloride (PVC)/nitrile rubber closed-cell foams as interior finish thermal insulation under conditions directly translatable to an actual fire situation. Flashover did not occur with the P-N foam and only moderate amounts of low density smoke were formed, whereas with the PVC/nitrile foam, flashover occurred quickly and large volumes of high density smoke were emitted. The P-N foam was produced in a pilot plant under carefully controlled conditions. The PVC/nitrile foam was a commercial product. A major phase of the overall program involved fire tests on P-N open-cell foam cushioning.

  3. Effect of gamma irradiation on the properties of natural rubber/styrene butadiene rubber blends

    Directory of Open Access Journals (Sweden)

    A.B. Moustafa


    Full Text Available Blends of natural rubber (NR with styrene butadiene rubber (SBR with varying ratios have been prepared. Vulcanization of the prepared blends has been induced by irradiation of gamma rays with varying doses up to 250 kGy. Mechanical properties, namely tensile strength, tensile modulus at 100% elongation, elongation at break have been followed up as a function of irradiation dose as well as blend composition. Physical properties, namely gel fraction and swelling number have been followed up using benzene as a solvent. Thermal measurements namely thermogravimetric analysis were carried out. The results indicated that the addition of NR has improved the properties of NR / SBR blends. Also NR/SBR blend is thermally stable than NR alone.

  4. Functionalization of Liquid Natural Rubber via Oxidative Degradation of Natural Rubber

    Directory of Open Access Journals (Sweden)

    Suhawati Ibrahim


    Full Text Available Natural rubber (NR is a high molecular weight natural polymer and can be degraded to liquid natural rubber (LNR leaving certain functional groups at the end of chains. In this study, LNR samples prepared via oxidative degradation using H2O2 and NaNO2 as reagents were found to have different end groups depending on the pH of the reaction medium. In an acidic medium, LNR with hydroxyl terminal groups was formed as the degradation reaction was initiated by hydroxyl radicals produced from decomposition of peroxynitrite acid. In contrast, a redox reaction took place in an alkaline medium to yield LNR with carbonyl terminal groups. The mechanisms of reaction are discussed and proposed to explain the formation of different end groups when reaction carried out in acidic and alkaline media. Chain degradation in an acidic medium seems to be more effective than in an alkaline medium, and thus yields LNR with lower Mn.

  5. The cross linking of EPDM and NBR rubber

    Directory of Open Access Journals (Sweden)

    Samardžija-Jovanović Suzana


    Full Text Available In the process of macromolecule cross linking, the choice of type and quantity of the components and the experimental conditions are important to obtain the new cross linked materials with better mechanical and chemical characteristics. The cross linking method depends on the rubber type and structure. Intermolecular cross linking results in the formation elastomer network. The basis of the cross linking process, between ethylene propylene diene rubber (EPDM and acrylonitrile butadiene rubber (NBR, is a chemical reaction. Fillers and other additives are present in different mass ratios in the material. The exploitation properties of the cross linked materials depend on the quantity of additive in the cross linked systems.

  6. Shear Flow Induced Alignment of Carbon Nanotubes in Natural Rubber

    Directory of Open Access Journals (Sweden)

    Yan He


    Full Text Available A new procedure for the fabrication of natural rubber composite with aligned carbon nanotubes is provided in this study. The two-step approach is based on (i the preparation of mixture latex of natural rubber, multiwalled carbon nanotubes, and other components and (ii the orientation of carbon nanotubes by a flow field. Rubber composite sheets filled with variable volume fraction of aligned carbon nanotubes were fabricated and then confirmed by transmission electron microscopy and Raman spectroscopy studies. An obvious increase in thermal conductivity has been obtained after the alignment of carbon nanotubes. The dynamic mechanical analysis was carried out in a tear mode for the composite.

  7. A kinetic model of reversion type cure for rubber compounds

    Energy Technology Data Exchange (ETDEWEB)

    Han, I.S.; Chung, C.B.; Kang, S.J.; Kim, S.J. [Chonnam National University, Kwangju (Korea, Republic of); Jung, H.C. [Research and Development Center of Kumho Tire Co., Ltd., Kwangju (Korea, Republic of)


    A cure kinetic model was presented to explain the reversion and the induction period commonly found in the vulcanization of rubber compounds. The model has three kinetic rate constants and one induction time which should be determined on the basis of isothermal rheometer curves. The torque curves calculated using the estimated parameters showed an excellent agreement with the measured curves for two rubber samples. An Arrhenius type relation was adopted to account for the temperature dependence of each kinetic parameter, and the corresponding Arrhenius plot showed very good linearity. It was shown that the proposed model can be used for predicting the state of cure for rubber compounds which undergo nonisothermal cure steps.


    Directory of Open Access Journals (Sweden)

    Bustanul Arifin


    Full Text Available Normal 0 false false false MicrosoftInternetExplorer4 st1\\:*{behavior:url(#ieooui } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} The study examines the supply chain of natural rubber production in Indonesia and assessing the transmission of prices to rubber growers and provides recommendations for a suitable scheme that would help to ensure high production standards and a sustainable return for natural rubber production.  The frameworks to examine the performance of supply chain of rubber marketing rely mostly on the efficiency level of marketing system of natural rubbers, including the value chain principles in marketing margin, and revealed price transmission from consumers to growers. The results show that the roles of subdistrict middlemen are extremely crucial in moving up the slabs from the village level to urban areas, where trader-brokers are expecting the slabs to be forwarded directly to crumb-rubber factories.  Changes in world price, hence the profits being accumulated by traders and rubber factories, are not transmitted properly to rubber farmers and/or sharetappers. Information asymmetry, the access over price information, and immediate response of rubber growers to the change in world price could explain this non-cointegration in price data between growers and exporters.  In the near future, the policy reforms in supply chain of natural rubber marketing in Indonesia should carefully address these issues in a more comprehensive manner.  Finally, in order to contribute to the positive environmental and social benefits, the major challenge for natural rubber

  9. Interfacial interaction between the epoxidized natural rubber and silica in natural rubber/silica composites (United States)

    Xu, Tiwen; Jia, Zhixin; Luo, Yuanfang; Jia, Demin; Peng, Zheng


    The epoxidized natural rubber (ENR) as an interfacial modifier was used to improve the mechanical and dynamical mechanical properties of NR/silica composites. In order to reveal the interaction mechanism between ENR and silica, the ENR/Silica model compound was prepared by using an open mill and the interfacial interaction of ENR with silica was investigated by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), X-ray diffraction (XRD) and stress-strain testing. The results indicated that the ring-opening reaction occurs between the epoxy groups of ENR chains and Si-OH groups on the silica surfaces and the covalent bonds are formed between two phases, which can improve the dispersion of silica in the rubber matrix and enhance the interfacial combination between rubber and silica. The ring-opening reaction occurs not only in vulcanization process but also in mixing process, meanwhile, the latter seems to be more important due to the simultaneous effects of mechanical force and temperature.

  10. Self-healing properties of carbon nanotube filled natural rubber/bromobutyl rubber blends

    Directory of Open Access Journals (Sweden)

    H. H. Le


    Full Text Available In the present work, the development and characterization of an intrinsically self-healable material based on butyl imidazole modified bromobutyl rubber (BIIR/natural rubber (NR blends, which are filled with carbon nanotubes (CNTs are reported. It was found that the addition of CNTs and the blending with NR significantly enhance the tensile strength of the BIIR composites. The use of butyl imidazole as physical cross-linker for the BIIR phase provides the blend composites the non-covalent bondings, which are responsible for their self-healing properties. Owing to the increase of the viscosity of the BIIR phase upon its physical crosslinking the island-matrix morphology of the blend changes over to a co-continuous structure. The preferential wetting of the CNT surface by the low-loading NR phase in the NR/BIIR blends can be explained by the good rubber-filler interaction between the linked phospholipids of the NR molecules and the π-electrons of the CNT surface. As a result, the favored localization of the CNTs in the NR phase strongly improves the electrical properties of the blends according to the double percolation theory. On the other hand it does not deteriorate the self-healing of the BIIR phase. The high electrical conductivity provides us a possibility to heat the blend by application of an electrical voltage in order to accelerate the self-healing process.

  11. Interfacial interaction between the epoxidized natural rubber and silica in natural rubber/silica composites

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Tiwen [College of Materials Science and Engineering, South China University of Technology, Guangzhou 510640 (China); Jia, Zhixin, E-mail: [College of Materials Science and Engineering, South China University of Technology, Guangzhou 510640 (China); Luo, Yuanfang; Jia, Demin [College of Materials Science and Engineering, South China University of Technology, Guangzhou 510640 (China); Peng, Zheng [Agricultural Product Processing Research Institute, Chinese Academy of Tropical Agriculture Sciences, Zhanjiang 524001 (China)


    Highlights: • Substantiate the ring open reaction between Si-OH of silica and epoxy groups of ENR. • ENR can act as a bridge between NR and silica to enhance the interfacial interaction. • As a modifier, ENR gets the potential to be used in the tread of green tire for improving the wet skid resistance apparently. - Abstract: The epoxidized natural rubber (ENR) as an interfacial modifier was used to improve the mechanical and dynamical mechanical properties of NR/silica composites. In order to reveal the interaction mechanism between ENR and silica, the ENR/Silica model compound was prepared by using an open mill and the interfacial interaction of ENR with silica was investigated by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), X-ray diffraction (XRD) and stress–strain testing. The results indicated that the ring-opening reaction occurs between the epoxy groups of ENR chains and Si-OH groups on the silica surfaces and the covalent bonds are formed between two phases, which can improve the dispersion of silica in the rubber matrix and enhance the interfacial combination between rubber and silica. The ring-opening reaction occurs not only in vulcanization process but also in mixing process, meanwhile, the latter seems to be more important due to the simultaneous effects of mechanical force and temperature.

  12. Effect of Nanoclay on Natural Rubber Microstructure

    Energy Technology Data Exchange (ETDEWEB)

    Carretero-Gonzalez,J.; Retsos, H.; Verdejo, R.; Toki, S.; Hsiao, B.; Giannelis, E.; Lopez-Manchado, M.


    The inclusion of highly anisotropic clay nanoparticles (nanoclays) in cross-linked natural rubber (NR) provides a more homogeneous distributed network structure and induces an early onset as well as enhancement of crystallization under uniaxial deformation. The molecular structure of the polymer network and its morphological changes during deformation were characterized by using broadband dielectric spectroscopy and in situ synchrotron wide-angle X-ray diffraction, respectively. It was found that the presence of nanoclay introduces a dual crystallization mechanism due to the alignment of nanoparticles during stretching. The improved properties in NR-nanoclay nanocomposites can be attributed to both microstructural and morphological changes induced by nanoclay as well as to the nanoclay mobility in the NR matrix during crystallization. The interplay of these factors during deformation contributes to the formation of a supernetwork structure containing cross-linked chemical chains, nanofiller, and crystallizable networks with similar length scales.

  13. The rubber hand illusion in a mirror. (United States)

    Bertamini, Marco; Berselli, Nausicaa; Bode, Carole; Lawson, Rebecca; Wong, Li Ting


    In the rubber hand illusion (RHI) one's hand is hidden, and a fake hand is visible. We explored the situation in which visual information was available indirectly in a mirror. In the mirror condition, compared to the standard condition (fake hand visible directly), we found no reduction of the RHI following synchronised stimulation, as measured by crossmanual pointing and by a questionnaire. We replicated the finding with a smaller mirror that prevented visibility of the face. The RHI was eliminated when a wooden block replaced the fake hand, or when the hand belonged to another person or mannequin. We conclude that awareness of the reflection is the critical variable, despite the distant visual localisation of the hand in a mirror and the third-person perspective. Stimuli seen in a mirror activate the same response as stimuli seen in peripersonal space, through knowledge that they are near one's body. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Polybenzoxazole-filled nitrile butadiene rubber compositions (United States)

    Gajiwala, Himansu M. (Inventor); Guillot, David G. (Inventor)


    An insulation composition that comprises at least one nitrile butadiene rubber (NBR) having an acrylonitrile content that ranges from approximately 26% by weight to approximately 35% by weight and polybenzoxazole (PBO) fibers. The NBR may be a copolymer of acrylonitrile and butadiene and may be present in the insulation composition in a range of from approximately 45% by weight to approximately 56% by weight of a total weight of the insulation composition. The PBO fibers may be present in a range of from approximately 3% by weight to approximately 10% by weight of a total weight of the insulation composition. A rocket motor including the insulation composition and a method of insulating a rocket motor are also disclosed.

  15. Crumb Rubber in cold recycled bituminous mixes

    DEFF Research Database (Denmark)

    Dondi, Giulio; Tataranni, Piergiorgio; Pettinari, Matteo


    Today recycling is one of the most innovative and interesting techniques for the rehabilitation of destressed road pavements. In recent years the increased interest in this process, has led to the development of various alternative methods for the recovery and the reuse of road bituminous materials....... Cold recycling is, among the recycling techniques, certainly the most studied and developed: it allows the recovering of bituminous material from an existing pavement without the addition of heat, whilst ensuring the creation of high quality bound base layers. A wide range of materials have been tested...... together with Reclaimed Asphalt Pavement (RAP) and, consequently, there is a large number of variables that can be considered in the mix-design process of new eco-friendly Cold Recycled Mixes. In particular, the present research involves the use of Crumb Rubber within a mixture containing 100% Reclaimed...

  16. Behavior of Rubber Materials under Exposure to High Electric Fields

    DEFF Research Database (Denmark)

    Candela Garolera, Anna; Holbøll, Joachim; Henriksen, M,


    The effect of high electrical stress on rubber materials is investigated by performing breakdown tests and tracking resistance tests on selected samples. The study is focused on the relationship between the dielectric strength and the thickness of the samples, as well as the influence of the inte......The effect of high electrical stress on rubber materials is investigated by performing breakdown tests and tracking resistance tests on selected samples. The study is focused on the relationship between the dielectric strength and the thickness of the samples, as well as the influence...... of the interfaces between different layers of material. Tracking resistance tests are also performed on the rubber material. The purpose is to provide a complete study of the applicability of the rubber material in thunderstorm environments....

  17. Method for Molding Structural Parts Utilizing Modified Silicone Rubber (United States)

    Weiser, Erik S. (Inventor); Baucom, Robert M. (Inventor); Snoha, John J. (Inventor)


    This invention improves upon a method for molding structural parts from preform material. Preform material to be used for the part is provided. A silicone rubber composition containing entrained air voids is prepared. The silicone rubber and preform material assembly is situated within a rigid mold cavity used to shape the preform material to die desired shape. The entire assembly is heated in a standard heating device so that the thermal expansion of the silicone rubber exerts the pressure necessary to force the preform material into contact with the mold container. The introduction of discrete air voids into the silicone rubber allows for accurately controlled pressure application on the preform material at the cure temperature.

  18. Super Lightweight, Metal Rubber Fabric for Extreme Space Environments Project (United States)

    National Aeronautics and Space Administration — NanoSonic has fabricated revolutionary nanostructured, yet macroscale, multifunctional Metal RubberTM films via layer-by-layer, molecular self-assembly, which...

  19. Metal Rubber Sensor Appliquis for Rotor Blade Air Project (United States)

    National Aeronautics and Space Administration — Thin film Metal RubberTM sensor appliqus have the potential to reduce the time, complexity and cost of measuring air flow-induced skin friction during the...

  20. Thermodynamics of a Simple Rubber-Band Heat Engine (United States)

    Mullen, J. G.; And Others


    Outlines the basic engine design and nomenclature, develops some relations between the state parameters of the rubber-band system, defines engine efficiency, and compares the Archibald engine with the Carnot engine. (GS)

  1. Multifunctional, Nanostructured Metal Rubber Protective Films for Space Exploration Project (United States)

    National Aeronautics and Space Administration — NanoSonic has developed revolutionary nanostructured, yet macroscale, multifunctional Metal RubberTM films. In support of NASA's Vision for Space Exploration, low...

  2. ORIGINAL ARTICLES Allergenicity of latex rubber products used in ...

    African Journals Online (AJOL)

    , to minimise the risk of sensitisation to these proteins. Background. Allergens from latex products in health care settings are known to trigger latex-induced allergic reactions in HCWs. Adverse effects associated with the use of latex rubber ...

  3. Amplitude-temperature analysis of hard rubber by torsional vibration

    Czech Academy of Sciences Publication Activity Database

    Šulc, Petr; Pešek, Luděk; Bula, Vítězslav; Cibulka, Jan; Košina, Jan


    Roč. 821, č. 2016 (2016), s. 295-302 ISSN 1660-9336 Institutional support: RVO:61388998 Keywords : hard rubber * torsion vibration * finite deformation * parameter identification Subject RIV: BI - Acoustics

  4. Tailoring magnetic and dielectric properties of rubber ferrite ...

    Indian Academy of Sciences (India)


    Department of Polymer Science and Rubber Technology, Cochin University of Science and. Technology, Cochin 682 022, India. ‡Physical Chemistry Division, National Chemical Laboratory, Pune 411 008, India. MS received 14 May 2001.

  5. Effect of Graphite on the Properties of Natural Rubber

    Directory of Open Access Journals (Sweden)

    Auda jabber Braihi


    Full Text Available Natural rubber-graphite composites (0, 1, 2, 3, 4 pphr graphite were prepared on a laboratory two-roll mill. Swelling measurements were used to evaluate the impacts of graphite on the properties of natural rubber. Swelling results showed that the volume fraction of natural rubber in the swollen gel, the interaction parameter, and the cross-link density decreased by increasing graphite loadings, while the average molecular weight of natural rubber between cross-links increased. Vulcanization results showed that only scorch time parameter increased with increasing graphite loadings, while other parameters (Max. torque, Min. torque, cure rate and cure rate index decreased. Both thermal and AC conductivities increased.

  6. Strength of Concrete Containing Rubber Particle as Partial Cement Replacement

    Directory of Open Access Journals (Sweden)

    Abdullah Siti Radziah


    Full Text Available Uncontrolled issues of disposal waste tire rubber create huge environmental impact and health hazards. An alternative viable solution to minimize these problems is by utilizing the waste rubber tires in construction materials, which in turn can reduce the use of natural resources and eventually lessen the cost of construction. This paper mainly focuses on the use of waste rubber tires particles in concrete with different set of composition ranging from 3 to 12% of cement replacement. Concrete cubes size of 150mm x 150mm x 150mm were prepared for compressive strength test, and concrete cylinders size of 150m x 300mm were prepared for splitting tensile test. The result shows that the compressive and split tensile strength of concrete with rubber as cement replacements is 6-21% lower than the normal concrete.

  7. High breakdown-strength composites from liquid silicone rubbers

    DEFF Research Database (Denmark)

    Vudayagiri, Sindhu; Zakaria, Shamsul Bin; Yu, Liyun


    In this paper we investigate the performance of liquid silicone rubbers (LSRs) as dielectric elastomer transducers. Commonly used silicones in this application include room-temperature vulcanisable (RTV) silicone elastomers and composites thereof. Pure LSRs and their composites with commercially...

  8. Lightweight Metal RubberTM Sensors and Interconnects Project (United States)

    National Aeronautics and Space Administration — The objective of this NASA Phase II program is to develop and increase the Technology Readiness Level of multifunctional Metal RubberTM (MRTM) materials that can be...

  9. Radiation Resistant, Reconfigurable, Shape Memory Metal Rubber Space Arrays Project (United States)

    National Aeronautics and Space Administration — NanoSonic has demonstrated that Shape Memory Metal RubberTM (SM-MR) adaptive skins exhibit reconfigurable and durable RF properties. It is hypothesized that such...

  10. Advanced Metal Rubber Sensors for Hypersonic Decelerator Entry Systems Project (United States)

    National Aeronautics and Space Administration — NanoSonic proposes to design and develop light-weight, low-modulus, and durable Metal Rubber™ sensors for aeroelastic analysis of Hypersonic Decelerator Entry...

  11. Utilization of surface-treated rubber particles from waste tires

    Energy Technology Data Exchange (ETDEWEB)

    Smith, F.G. [Argonne National Lab., IL (United States). Energy Systems Div.]|[Environmental Technologies Alternatives, Inc., Lima, OH (United States)


    During a 12-month program, the author successfully demonstrated commercial applications for surface-treated rubber particles in two major markets: footwear (shoe soles and components) and urethane-foam carpet underlay (padding). In these markets, he has clearly demonstrated the ease of using R-4080 and R-4030 surface-treated rubber particles in existing manufacturing plants and processes and have shown that the material meets or exceeds existing standards for performance, quality, and cost-effectiveness. To produce R-4080 and R-4030, vulcanized rubber, whole-tire material is finely ground to particles of nominal 80 and mesh size respectively. Surface treatment is achieved by reacting these rubber particles with chlorine gas. In this report, the author describes the actual test and evaluations of the participant companies, and identifies other potential end uses.

  12. Enhanced performance of crumb rubber filtration for ballast water treatment. (United States)

    Tang, Zhijian; Butkus, Michael A; Xie, Yuefeng F


    Waste-tire-derived crumb rubber was utilized as filter media to develop an efficient filter for ballast water treatment. In this study, the effects of coagulation, pressure filtration and dual-media (gravity) filtration on the performance of the crumb rubber filtration were investigated. The removal efficiencies of turbidity, phytoplankton and zooplankton, and head loss development were monitored during the filtration process. The addition of a coagulant enhanced the removal efficiencies of all targeted matter, but resulted in substantial increase of head loss. Pressure filtration increased filtration rates to 220 m(3)h(-1)m(-2) for 8-h operation and improved the zooplankton removal. Dual-media (crumb rubber/sand) gravity filtration also improved the removal efficiencies of phytoplankton and zooplankton over mono-media gravity crumb rubber filtration. However, these filtration techniques alone did not meet the criteria for removing indigenous organisms from ballast water. A combination of filtration and disinfection is suggested for future studies.

  13. Characterization of weed flora in rubber trees plantations of Bongo ...

    African Journals Online (AJOL)



    Oct 31, 2013 ... Rubiaceae, Apocynaceae, Poaceae, Cyperaceae, Euphorbiaceae, Moraceae, Amaranthaceae,. Mimosaceae, Fabaceae, Cucurbitaceae and Commelinaceae. Weeds' mapping was established and illustrated by 4 main weed groups in relation with the stage of rubber trees development. For the plantations.

  14. Analysis of temperature profile and electric field in natural rubber glove due to microwave heating: effects of waveguide position (United States)

    Keangin, P.; Narumitbowonkul, U.; Rattanadecho, P.


    Natural rubber (NR) is the key raw material used in the manufacture of other products such as rubber band, tire and shoes. Recently, the NR is used in natural rubber glove ( NRG) manufacturing in the industrial and medical fields. This research aims to investigate the electromagnetic wave propagation and heat transfer in NRG due to heating with microwave energy within the microwave oven at a microwave frequency of 2.45 GHz. Three-dimensional model of NRG and microwave oven are considered in this work. The comparative effects of waveguide position on the electric field and temperature profile in NRG when subjected to microwave energy are discussed. The finite element method (FEM) is used to solve the transient Maxwell’s equation coupled with the transient heat transfer equation. The simulation results with computer programs are validated with experimental results. The placement of waveguides in three cases are left hand side of microwave oven, right hand side of microwave oven and left and right hand sides of microwave oven are investigated. The findings revealed that the placing the waveguide on the right side of the microwave oven gives the highest electric field and temperature profile. The values obtained provide an indication toward understanding the study of heat transfer in NRG during microwave heating in the industry.

  15. Education and Industry: Taking Two Steps Back and Reflecting (United States)

    Keep, Ewart


    This article focuses on a range of macro-level issues that frame debates about industry/education interaction in the UK. It explores a number of features that underpin the structure of the debate, including the declining "Britishness" of much of British business and the emergence of business as a for-profit provider of learning. It then…

  16. Time series analysis of the behavior of brazilian natural rubber

    Directory of Open Access Journals (Sweden)

    Antônio Donizette de Oliveira


    Full Text Available The natural rubber is a non-wood product obtained of the coagulation of some lattices of forest species, being Hevea brasiliensis the main one. Native from the Amazon Region, this species was already known by the Indians before the discovery of America. The natural rubber became a product globally valued due to its multiple applications in the economy, being its almost perfect substitute the synthetic rubber derived from the petroleum. Similarly to what happens with other countless products the forecast of future prices of the natural rubber has been object of many studies. The use of models of forecast of univariate timeseries stands out as the more accurate and useful to reduce the uncertainty in the economic decision making process. This studyanalyzed the historical series of prices of the Brazilian natural rubber (R$/kg, in the Jan/99 - Jun/2006 period, in order tocharacterize the rubber price behavior in the domestic market; estimated a model for the time series of monthly natural rubberprices; and foresaw the domestic prices of the natural rubber, in the Jul/2006 - Jun/2007 period, based on the estimated models.The studied models were the ones belonging to the ARIMA family. The main results were: the domestic market of the natural rubberis expanding due to the growth of the world economy; among the adjusted models, the ARIMA (1,1,1 model provided the bestadjustment of the time series of prices of the natural rubber (R$/kg; the prognosis accomplished for the series supplied statistically adequate fittings.

  17. Deformation-Induced Crystallization In Rubber-Like Materials


    Saidan, Motasem


    Deformation induced crystallization is crucial for determining the final mechanical properties of elastomers-rubber. Elastomeric networks show high upturn in the stress-strain curves with a significant hysteresis, this is attributed to the deformation induced crystallization phenomenon. Thermodynamics of rubber-like high polymers have been studied, and uniaxial extension with some approximations is discussed to obtain an overview of the proposed thermodynamic constitutive theory. A thermodyna...

  18. Characterization of Rubbers from Spherical Punch - Plate Indentation Tests

    Directory of Open Access Journals (Sweden)

    Florina Carmen Ciornei


    Full Text Available Rubber plates with different compositions and hardness were tested by continuous indentation, using a spherical punch and hysteretic phenomenon was evidenced. The experimental data interpolation with polynomial functions is accurate and permits estimation of the lost work during loading cycles. The interpolation by power law functions is more convenient by using less parameters and having a form accepted in literature. From the rubbers tested, two were considered to present good damping properties.

  19. Altered levels of the Taraxacum kok-saghyz (Russian dandelion) small rubber particle protein, TkSRPP3, result in qualitative and quantitative changes in rubber metabolism. (United States)

    Collins-Silva, Jillian; Nural, Aise Taban; Skaggs, Amanda; Scott, Deborah; Hathwaik, Upul; Woolsey, Rebekah; Schegg, Kathleen; McMahan, Colleen; Whalen, Maureen; Cornish, Katrina; Shintani, David


    Several proteins have been identified and implicated in natural rubber biosynthesis, one of which, the small rubber particle protein (SRPP), was originally identified in Hevea brasiliensis as an abundant protein associated with cytosolic vesicles known as rubber particles. While previous in vitro studies suggest that SRPP plays a role in rubber biosynthesis, in vivo evidence is lacking to support this hypothesis. To address this issue, a transgene approach was taken in Taraxacum kok-saghyz (Russian dandelion or Tk) to determine if altered SRPP levels would influence rubber biosynthesis. Three dandelion SRPPs were found to be highly abundant on dandelion rubber particles. The most abundant particle associated SRPP, TkSRPP3, showed temporal and spatial patterns of expression consistent with patterns of natural rubber accumulation in dandelion. To confirm its role in rubber biosynthesis, TkSRPP3 expression was altered in Russian dandelion using over-expression and RNAi methods. While TkSRPP3 over-expressing lines had slightly higher levels of rubber in their roots, relative to the control, TkSRPP3 RNAi lines showed significant decreases in root rubber content and produced dramatically lower molecular weight rubber than the control line. Not only do results here provide in vivo evidence of TkSRPP proteins affecting the amount of rubber in dandelion root, but they also suggest a function in regulating the molecular weight of the cis-1, 4-polyisoprene polymer. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Industrial recovered-materials-utilization targets for the textile-mill-products industry

    Energy Technology Data Exchange (ETDEWEB)



    The Congress, in the National Energy Conservation and Policy Act of 1978 (NECPA), directed the Department of Energy to establish materials recovery targets for the metals and metal products, paper and allied products, rubber, and textile-mill-products industries. The targets were developed to provide incentives for using energy-saving recorded materials and to provied a yardstick for measuring progress and improvement in this endeavor. The NECPA indicates that the targets should represent the maximum technically and economically feasible increase in the use of energy-saving recovered materials that each industry can achieve progressively by January 1, 1987. Materials affected by recovered-materials targets include and are limited to aluminum, copper, lead, zinc, iron, steel, paper and associated products, textile-mill, products, and rubber. Using information gathered from the textile-mill-products industry and from other textile-relaed sources, DOE has developed recovered materials targets for that industry. This report presents those targets and their basis and justification. Following an overview of the textile industry, the chapters are: Textile-Mill-Products Industry Operations; Economic Analysis of the Textile-Mill-Products Industry; Governmental and Regulatory Influence on the US Textile Industry; Current Mill Use of Recovered Materials in the Textile-Mill-Products Industry; Limitations on the Use of Recovered Materials in the US Textile-Mill-Products Industry; Materials-Recovery Targets; and Government and Industry Actions That Could Increase the Use of Recovered Materials.

  1. British Teachers' Transnational Work within and beyond the British Empire after the Second World War (United States)

    Whitehead, Kay


    Focusing on British graduates from Gipsy Hill Training College (GHTC) in London, this article illustrates transnational history's concerns with the reciprocal flows of people and ideas within and beyond the British Empire. GHTC's progressive curriculum and culture positioned women teachers as agents of change, and the article highlights the lives…

  2. Laboratory Evaluation of Ground Tire Rubber in Stone Mastic Asphalt

    Directory of Open Access Journals (Sweden)

    R. Muniandy


    Full Text Available Stone mastic asphalt (SMA is a gap-graded mix whereby stiffer asphalt cement is required to bind the stone matrix or arrangement of stones together. Although various asphalt additives are traditionally available, the use of rubber crumbs in SMA is still a new rresearch endeavor. Many countries around the world are facing serious problems on what to do with reject or discarded tires. In the present study, commercial truck tires, containing 70% natural rubber, were ground and pre-blended in 80-100 penetration asphalt for use in SMA mixtures. An assessment was made of the laboratory performance of rubberized SMA in terms of stability, resilent modulus, dynamic creep and tensile strength ratio. It was observed that the performance of SMA with ground tire rubber was for superior as compared to SMA mix with unmodified asphalt. Sulfur and Styrene Butadeline Rubber (SBR were used in rubberized SMA mixes as additives to test the sensitivity of SMA mixtures. As standard practice a 0.3% newly developed cellulose oil palm fiber was used in SMA to minimize the asphalt drain-down effects.

  3. Thermal behavior of silicone rubber-based ceramizable composites characterized by Fourier transform infrared (FT-IR) spectroscopy and microcalorimetry. (United States)

    Anyszka, Rafał; Bieliński, Dariusz M; Jędrzejczyk, Marcin


    Ceramizable (ceramifiable) silicone rubber-based composites are commonly used for cable insulation. These materials are able to create a protective ceramic layer during fire due to the ceramization process, which occurs at high temperature. When the temperature is increased, the polymer matrix is degraded and filler particles stick together by the fluxing agent, producing a solid, continuous ceramic phase that protects the copper wire from heat and mechanical stress. Despite increasing interest in these materials that has resulted in growing applications in the cable industry, their thermal behavior and ceramization process are still insufficiently described in the literature. In this paper, the thermal behavior of ceramizable silicone rubber-based composites is studied using microcalorimetry and Fourier transform infrared spectroscopy. The analysis of the experimental data made it possible to develop complete information on the mechanism of composite ceramization.

  4. Separation and identification of various vulcanization agents and antioxidants in two types of rubber by chromatographic and spectrometric methods. (United States)

    Chauveau, S; Hamon, M; Leleu, E


    The aim of this study was to separate and identify by chromatographic and spectrometric methods, the various allergenic vulcanization agents and antioxidants used in the manufacture of industrial rubber. Specimens of elastomers were manufactured specially for this study. The specificity of the gas chromatographic method developed allows separation of all the manufacturing additives in the selected rubber types after one injection only, even though they belong to extremely varied chemical categories. The GLC method was coupled with mass spectrometry, which permitted identification of the peaks obtained and the study of the fragmentation of the 4 reference products under various conditions. Separation by TLC was performed in parallel on the same extracts, allowing rapid identification of the products tested for, and showed new spots after vulcanization.

  5. Effect of filler water absorption on water swelling properties of natural rubber (United States)

    Trakuldee, J.; Boonkerd, K.


    The efficient water swelling rubber can be obtained by using high hydrophilic rubber such as chloroprene rubber. However, chloroprene rubber is synthetic rubber developed from the petroleum. Recently, many researches try to replace the usage of synthetic rubber with natural rubber. This is not only due to the concerning of environment but the cost reduction as well. However, natural rubber is hydrophobic, thus not absorbing water. To develop the water swelling rubber from natural rubber, the addition of water absorption filler is needed. The study was aimed to formulate water swelling rubber from natural rubber filled with sodium polyacrylate (SA)/sodium bentonite clay (SBC) hybrid filler used to water absorbent. The filler loading was kept constantly at 150 phr. The effect of SA/SBC ratio varied from 1:0, 1:1, 1:2 and 1:3 on the water absorption of the hybrid filled natural rubber was determined. The obtained result showed that the water adsorption proportionally increased with increasing SA loading but decreased with increasing SBC loading. The effect of glycidyl methacrylate (GM) and poly ethylene glycol (PEG) on the water absorption was studied later. The result from a scanning electron microscope depicted that the presence of GM can depress the falling out of SA from the rubber matrix while the presence of PEG increased water absorption.


    Directory of Open Access Journals (Sweden)

    FV Daraninggar


    Full Text Available Teknologi pengolahan limbah ban karet bekas hingga menghasilkan minyak bakar RCO (Rubber Compound Oils merupakan solusi menumpuknya ban bekas tidak terpakai. Namun limbah pembuatan minyak bakar RCO yang dibuang langsung berakibat pada pencemaran lingkungan. Tujuan dari penelitian ini adalah mengetahui nilai resistivitas dan pola sebaran 3-dimensi limbah industri RCO di daerah pabrik pengolahan ban bekas Kecamatan Boja, Kabupaten Kendal. Pengambilan data menggunakan metode geolistrik tahanan jenis konfigurasi Wenner dengan spasi antar elektroda lima meter. Data nilai resistivitas limbah industri minyak bakar RCO diolah menggunakan software IPI2Win, kemudian distribusi resistivitas digambarkan dalam bentuk 3-dimensi menggunakan software Res2dinv, Res3dinv, Slicer Dicer. Hasil interpretasi 3-dimensi menyimpulkan bahwa limbah industri minyak bakar RCO telah menyebar lebih dari 43,75 meter ke arah timur pabrik, lebih dari 20 meter ke arah utara dan kedalaman lebih dari 12 meter dengan nilai resistivitas 11-20 ohm.m. Limbah diduga tersebar pada lapisan tanah dengan struktur batuan lempung dan pasir. {0>Teknologi pengolahan limbah ban karet bekas hingga menghasilkan minyak bakar RCO (Rubber Compound Oils merupakan solusi menumpuknya ban bekas tidak terpakai.<}0{>Waste treatment technology of used rubber tires to produce RCO (Rubber Compound Oils fuel oil is a solution of the accumulatoin of abandoned used tires.<0} {0>Namun limbah pembuatan minyak bakar RCO yang dibuang langsung berakibat pada pencemaran lingkungan.<}0{>However, the oil conversion of dumped RCO wastes might cause environmental pollution.<0} {0>Tujuan dari penelitian ini adalah mengetahui nilai resistivitas dan pola sebaran 3-dimensi limbah industri RCO di daerah pabrik pengolahan ban bekas Kecamatan Boja, Kabupaten Kendal.<}0{>The purpose of this study was to determine the resistivity value and the pattern of 3D distribution of industrial RCO wastes in a treatment plant, subdistrict

  7. Explaining British Political Stability After 1832

    Directory of Open Access Journals (Sweden)

    Donagh Davis


    Full Text Available Though not its main focus, Goldstone's Revolution and Rebellion in the Early Modern World (1991 threw considerable new light on 19th century Europe's revolutions and near-revolutions. While Goldstone stresses the role of an expanding and industrializing economy in absorbing 19th century England's demographic shocks, we accept this analysis but argue alongside it for similar attention to the vector of emigration, settler-colonialism, and imperial state expansion into which at least some of the exhaust fumes of the population explosion were vented. Furthermore, it is important to note the crucial role of a highly interventionist state and 'big' government in the background to these dynamics—a far cry from the light-touch, laissez-faire qualities with which the 19th century British state is often associated. To make our case, this article takes advantage of secondary literature and raw data not available prior to the publication of Goldstone's book. Of crucial importance here is our unique dataset of fatality-inducing political violence events in Britain and Ireland from 1785 to 1900. This is the first research paper to utilise this dataset. We draw upon this in the following section, which seeks to establish what the real level of political instability was in 19th century Britain—thus cross-referencing Goldstone's account with more recent data—before moving on in the following section to a more detailed overview of the socio-economic conditions underlying events at the political level. This is followed by our account of the emigration-settler-colonialism-imperial state expansion vector and the interventionist state policy behind it, which we argue was crucial to making 19th century Britain relatively 'revolution-proof'—alongside the expanding economic opportunities rightly highlighted by Goldstone. Lastly come our brief concluding remarks, which lay out the implications, as we see them, of this article's findings for research on

  8. Characterization and functional expression of a rubber degradation gene of a Nocardia degrader from a rubber-processing factory. (United States)

    Linh, Dao Viet; Huong, Nguyen Lan; Tabata, Michiro; Imai, Shunsuke; Iijima, Sou; Kasai, Daisuke; Anh, To Kim; Fukuda, Masao


    A rubber-degrading bacterial consortium named H2DA was obtained from an enrichment culture with natural rubber latex and rubber-processing factory waste in Vietnam. Gel permeation chromatography analysis revealed that only the strain NVL3 degraded synthetic poly(cis-1,4-isoprene) into low-molecular-weight intermediates among the three strains found in the H2DA. The 16S-rRNA gene sequence of NVL3 showed the highest identity with that of Nocardia farcinica DSM 43665T. NVL3 accumulated aldehyde intermediates from synthetic poly(cis-1,4-isoprene) on a rubber-overlay plate as indicated by Schiff's staining. NVL3 also degraded deproteinized natural rubber into low-molecular-weight aldehyde intermediates. A latex-clearing protein (lcp) gene ortholog was identified within the genome sequence of NVL3, and it showed a moderate amino-acid identity (54-75%) with the lcp genes from previously reported rubber degraders. The heterologous expression of the NVL3 lcp in Escherichia coli BL21(DE3) allowed us to purify the 46.8-kDa His-tagged lcp gene product (His-Lcp). His-Lcp degraded synthetic poly(cis-1,4-isoprene) and accumulated aldehyde intermediates from deproteinized natural rubber suggesting the functional expression of the lcp gene from a Nocardia degrader in E. coli. Quantitative reverse transcription PCR analysis indicated the strong transcriptional induction of the lcp gene in NVL3 in the presence of synthetic poly(cis-1,4-isoprene). These results suggest the involvement of the lcp gene in rubber degradation in NVL3. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  9. Phonemic Transcriptions in British and American Dictionaries

    Directory of Open Access Journals (Sweden)

    Rastislav Šuštaršič


    Full Text Available In view of recent criticisms concerning vowel symbols in some British English dictionaries (in particular by J. Windsor Lewis in JIPA (Windsor Lewis, 2003, with regard to the Oxford Dictionary of Pronunciation (Upton, 2001, this article extends the discussion on English phonemic transcriptions by including those that typically occur in standard American dictionaries, and by comparing the most common conventions of British and American dictionaries. In addition to symbols for both vowels and consonants, the paper also deals with the different representations of word accentuation and the issue of consistency regarding application of phonemic (systemic, broad, rather than phonetic (allophonic, narrow transcription. The different transcriptions are assessed from the points of view of their departures from the International Phonetic Alphabet, their overlapping with orthographic representation (spelling and their appropriateness in terms of reflecting actual pronunciation in standard British and/or American pronunciation.

  10. Effect of type and content of tackifier on adhesion of natural rubber and reclaimed natural rubber based sealant (United States)

    Raethong, P.; Boonkerd, K.


    Adhesion property of natural rubber (NR) and reclaimed natural rubber (RNR) based sealant with concrete was studied here. The effect of tackifier type and loading on the tensile properties of the rubber based sealant sandwished between two flat cements was evaluated. There are three different tackifiers including Coumarone-indene resin (CI), petro resin (PE) and gum rosin (GR). The result initially showed that at the 20 phr of tackifier both NR and RNR sealant mixed with CI consumed the highest force to separate the rubber based sealant from the concrete. This might be due to the highest compatiblility between CI and rubber. Regardless of the tackifier type, all NR based sealants showed the cohesive failure while all RNR based sealants only showed the adhesive failure. Moreover, the NR based sealant seemed to be stronger than the RNR based one. When considering the effect of CI loading on the adhesion, it was shown that for both NR and RNR based sealents, the highest stress was observed when the rubber based sealant loaded with the 20 phr of CI.

  11. Effects of Polarity on the Filler-Rubber Interaction and Properties of Silica Filled Grafted Natural Rubber Composites

    Directory of Open Access Journals (Sweden)

    Wanvimon Arayapranee


    Full Text Available The grafting of an olefinic monomer like acrylonitrile (AN, methyl methacrylate (MMA, and styrene (ST onto natural rubber (NR was carried out to enhance the polarity of the new chemical groups on the NR backbone and, in turn, to improve the filler-rubber interaction. The grafted natural rubber (GNR produced was compounded and then vulcanization was carried out in the presence of silica as a reinforcing filler. The physical properties and aging resistance provided by the presence of the polar functional groups of the GNR composites were investigated and compared with other rubbers such as SBR, NBR, and NR. The GNRs provided significant improvements in resistance of the composites to thermal, oil, and ozone while maintaining the mechanical properties of the rubber. Therefore, these properties can be controlled as a function of the polarity of functional groups on the NR backbone. Morphological studies confirmed a shift from ductility failure to brittle with the presence of the polar group on the rubber chains.

  12. Pilot Scale Production of Irradiated Natural Rubber Latex and its Dipping Products


    M. Utama; Suhartini, M; Herwinarni; (Siswanto), Siswanto; S. Yoharmus; H. Sundaru; H.M. Halik; Prayitno; H.M. Muklis; S. Ruslim


    One hundred and fifty kg natural rubber latex (NRL) before and after concentration were added with 3 phr (part hundred ratio of rubber) normal butyl acrylate, then the mixture were irradiated at 25 kGy by gamma rays of 60Co in pilot scale. The irradiated natural rubber latex (INRL) were then being to use for producing rubber products such as condom, surgical gloves, and spygmomanometer in factory scale. The quality of INRL and rubber products such as : total solid content (TSC), dry rubber co...

  13. Predicting the glass transition temperature as function of crosslink density and polymer interactions in rubber compounds (United States)

    D'Escamard, Gabriella; De Rosa, Claudio; Auriemma, Finizia


    Crosslink sulfur density in rubber compounds and interactions in polymer blends are two of the composition elements that affect the rubber compound properties and glass transition temperature (Tg), which is a marker of polymer properties related to its applications. Natural rubber (NR), butadiene rubber (BR) and styrene-butadiene rubber (SBR) compounds were investigated using calorimetry (DSC) and dynamic mechanical analysis (DMA). The results indicate that the Di Marzio's and Schneider's Models predict with accuracy the dependence of Tg on crosslink density and composition in miscible blends, respectively, and that the two model may represent the base to study the relevant "in service" properties of real rubber compounds.

  14. Dynamically vulcanized biobased polylactide/natural rubber blend material with continuous cross-linked rubber phase. (United States)

    Chen, Yukun; Yuan, Daosheng; Xu, Chuanhui


    We prepared a biobased material, dynamically vulcanized polylactide (PLA)/natural rubber (NR) blend in which the cross-linked NR phase owned a continuous network-like dispersion. This finding breaks the traditional concept of a sea-island morphology formed after dynamic vulcanization of the blends. The scan electron microscopy and dissolution/swell experiments provided the direct proof of the continuous cross-linked NR phase. This new biobased PLA/NR blend material with the novel structure is reported for the first time in the field of dynamic vulcanization and shows promise for development for various functional applications.

  15. The British Library's Vulnerable Collection Items Project

    Directory of Open Access Journals (Sweden)

    Kimberly C. Kowal


    Full Text Available The British Library embarked on a project in 2007 to better protect collection materials considered vulnerable. Following thefts of maps contained within books, a methodology was developed to firmly identify the unique copies of rare and valuable British Library holdings, using a range of security photography and copy-specific descriptive metadata. The outcome of the project not only served to improve the security of the selected maps, but by revealing these hidden collections, access to and knowledge of them is enhanced.

  16. A critical history of British earthquakes


    R. M. W. Musson


    This paper reviews the history of the study of historical British earthquakes. The publication of compendia of British earthquakes goes back as early as the late 16th Century. A boost to the study of earthquakes in Britain was given in the mid 18th Century as a result of two events occurring in London in 1750 (analogous to the general increase in earthquakes in Europe five years later after the 1755 Lisbon earthquake). The 19th Century saw a number of significant studies, culminating in th...


    Directory of Open Access Journals (Sweden)

    Yesipov Mikhail Alekseevich


    Full Text Available Communication culture formation belongs to most essential problems for pedagogical theory and practice. The level of a teacher’s communication culture influences greatly the efficiency of his professional communication with colleagues and students. The peculiarities of teachers’ communication culture formation in the British educational system are considered. Main characteristics of a communication-oriented teacher are mentioned. Criteria for specifying the level of British teachers’ communication culture formedness as well as brief description of these levels are given in this article.

  18. Cultural and age differences in beliefs about depression: British Bangladeshis vs. British Whites. (United States)

    McClelland, Alastair; Khanam, Shopnara; Furnham, Adrian


    This study examines beliefs about depression as a function of ethnic background (British Bangladeshis vs. British Whites) and age. A total of 364 participants completed a 65-item questionnaire, containing general questions regarding depression and anti-depressive behaviour; the causes of depression, and treatments for depression. The hypotheses were broadly supported; there were significant interactions between ethnicity and age, which generally revealed an increasingly negative attitude towards depression with increasing age amongst British Bangladeshis. Older British Bangladeshis believed depression was an illness that brought a sense of shame and loss of dignity to the individual and his or her family, and they also favoured a lay referral system for sufferers. They also had more superstitious beliefs about depression than both younger British Bangladeshis and British Whites. A pattern of increasing negativity with increasing age was not evident amongst the British Whites, but older individuals in both groups tended to believe that depression was not helped by psychological intervention. The attitudes towards depression in the young was similar (and generally positive) in both ethnic groups. These findings highlight the necessity to provide more culturally sensitive and accessible services for migrant communities - particularly amongst older individuals.

  19. [Rubber band ligation in treatment of hemorrhoids: our experience]. (United States)

    Gaj, F; Biviano, I; Sportelli, G; Candeloro, L


    Hemorrhoids are a very common condition. The treatment depends upon persistence and severity of symptoms. For hemorrhoids of II and III grade the rubber band ligation may be therapeutic. Our aim is to report the outcomes of rubber band ligation of hemorrhoids, with a follow up of 6 months. A total of 50 patients underwent rubber band ligation for symptomatic hemorrhoids (grade II and III) without prolapse, between June 2012 and June 2014. All patients underwent plug test to rule out presence of rectal mucosal prolapse and were classified according to PATE classification (1). Each hemorrhoid was ligated with one rubber band through a ligator. All patients were evaluated immediately at the end of the procedure, after ten days and six months after the treatment. Patient's demographic and operative data were collected and analyzed. The mean patients age was 47.6±12.3 years (range 24-72). All procedures were performed without complications. Before rubber band ligation, 42 patients had rectal bleeding, 38 had perineal discomfort and 27 had itching. Ten days after the treatment, 12 patients presented self-limited rectal bleeding, but 10 of these had more hemorrhoids and underwent a second rubber band ligation. No patients complained perineal discomfort, and 8 patients had itching; 78% and 16% of patients respectively, experienced feeling of a foreign body inside the canal anal and anal pain. After 6 months, only 13 patients were occasionally symptomatic: 4 patients had rectal bleeding, 2 had perineal discomfort and 4 had itching. Three more patients presented both perineal discomfort and hitching. None had the feeling of a foreign body in anal canal or anal pain. Rubber band ligation is an efficacious, cost-effective and simple treatment for the second and third degree hemorrhoids without rectal mucosal prolapsed. In our hands, no severe complications developed and minor complications could be handled with ease.


    Directory of Open Access Journals (Sweden)

    K. P. Kolnogorov


    Full Text Available Summary. This article discusses how to obtain amide-containing salts of 3d-metals based on tall rosin. A scheme of obtaining amide containing salts 3dmetals. The scheme of obtaining amide-containing salts of 3d-metals presented here. Ammonolysis maleopimaric acid was carried out, the technological parameters of the process were identified. Found that the process of ammonolysis affected by the following controlled technological factors: the ratio of the components, the temperature of the reaction medium and the duration of holding ammonolysis. The results of studies of the effect of additives on the received technical and technological properties of the elastomer compositions, adhesion and corrosion resistance rubber-systems are presented. The most efficient promoters are metalcord-rubber adhesion systems for use in the manufacture of tires fitted. Providing the necessary technological properties of manufacturing rubber compounds achieved when using elastomeric compositions consisting of a cobalt salt of amide MTC. Found that necessary to adjust the composition of the vulcanizing system using the synthesized compounds. It was revealed that the elastomeric composition comprising cobalt salt of amide maleated rosin and cobalt naphthenate are less susceptible to oxygen and air at elevated temperature compared to rubber containing salts Mn (II and Cr (III amide MTC. The results of studies of bond strength rubber with steel showed that the adhesive properties of rubber-systems with the test components depend on the dosage and rubber compound. It was determined that the introduction of salts of Co (II, based on amide maleated tall oil rosin at a dosage of 1.5 wt. parts per 100 wt. phr produces indicators adhesion and corrosion properties at the level of those with industrial modifier cobalt naphthenate. The results of research of obtained compounds influence on the technical and technological properties of the elastomer compositions, adhesion and

  1. Development of rubber mixing process mathematical model and synthesis of control correction algorithm by process temperature mode using an artificial neural network

    Directory of Open Access Journals (Sweden)

    V. S. Kudryashov


    Full Text Available The article is devoted to the development of a correction control algorithm by temperature mode of a periodic rubber mixing process for JSC "Voronezh tire plant". The algorithm is designed to perform in the main controller a section of rubber mixing Siemens S7 CPU319F-3 PN/DP, which forms tasks for the local temperature controllers HESCH HE086 and Jumo dTRON304, operating by tempering stations. To compile the algorithm was performed a systematic analysis of rubber mixing process as an object of control and was developed a mathematical model of the process based on the heat balance equations describing the processes of heat transfer through the walls of technological devices, the change of coolant temperature and the temperature of the rubber compound mixing until discharge from the mixer chamber. Due to the complexity and nonlinearity of the control object – Rubber mixers and the availability of methods and a wide experience of this device control in an industrial environment, a correction algorithm is implemented on the basis of an artificial single-layer neural network and it provides the correction of tasks for local controllers on the cooling water temperature and air temperature in the workshop, which may vary considerably depending on the time of the year, and during prolonged operation of the equipment or its downtime. Tempering stations control is carried out by changing the flow of cold water from the cooler and on/off control of the heating elements. The analysis of the model experiments results and practical research at the main controller programming in the STEP 7 environment at the enterprise showed a decrease in the mixing time for different types of rubbers by reducing of heat transfer process control error.

  2. About the cure kinetics in natural rubber/styrene Butadiene rubber blends at 433 K

    Energy Technology Data Exchange (ETDEWEB)

    Mansilla, M.A., E-mail: [Laboratorio de Polimeros y Materiales Compuestos, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon 1, C1428EGA Buenos Aires (Argentina); Marzocca, A.J. [Laboratorio de Polimeros y Materiales Compuestos, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon 1, C1428EGA Buenos Aires (Argentina)


    Vulcanized blends of elastomers are employed in several goods mainly to improve physical properties and reduce costs. One of the most used blends of this kind is that composed by natural rubber (NR) and styrene butadiene rubber (SBR). The cure kinetic of these blends depends mainly on the compound formulation and the cure temperature and time. The preparation method of the blends can influence the mechanical properties of the vulcanized compounds. In this work the cure kinetic at 433 K of NR/SBR blends vulcanized with the system sulfur/TBBS (N-t-butyl-2-benzothiazole sulfenamide) is analyzed in samples prepared by mechanical mixing and solution blending. The two methods produce elastomer domains of NR and SBR, which present different microstructure due to the cure level attained during vulcanization. The cure kinetics is studied by means of rheometer tests and the model proposed by Kamal and Sourour. The analysis of the cure rate is presented and is related to the structure obtained during the vulcanization process.

  3. The Great British Music Hall: Its Importance to British Culture and ‘The Trivial’

    Directory of Open Access Journals (Sweden)

    Steven Gerrard


    Full Text Available By 1960, Britain’s once-thriving Music Hall industry was virtually dead. Theatres with their faded notions of Empire gave way to Cinema and the threat of Television. Where thousands once linked arms singing popular songs, watch acrobatics, see feats of strength, and listen to risqué jokes, now the echoes of those acts lay as whispers amongst the stalls’ threadbare seats. The Halls flourished in the 19th Century, but had their origins in the taverns of the 16th and 17th Centuries. Minstrels plied their trade egged on by drunken crowds. As time passed, the notoriety of the Music Hall acts and camaraderie produced grew. Entrepreneurial businessman tapped into this commerciality and had purpose-built status symbol theatres to provide a ‘home’ for acts and punters. With names like The Apollo giving gravitas approaching Olympian ideals, so the owners basked in wealth and glory. The Music Hall became the mass populist entertainment for the population. Every town had one, where everyone could be entertained by variety acts showing off the performers’ skills. The acts varied from singers, joke-tellers, comics, acrobats, to dancers. They all aimed to entertain. They enabled audiences to share a symbiotic relationship with one another; became recruitment officers for the Army; inspired War Poets; showed short films; and they and the halls reflected both the ideals and foibles of their era. By using Raymond Williams’ structures of feeling as its cornerstone, the article will give a brief history of the halls, whilst providing analysis into how they grew into mass populist entertainment that represented British culture. Case studies of famous artistes are given, plus an insight into how Music Hall segued into radio, film and television.

  4. British Higher Education and Its Older Clients. (United States)

    Woodley, Alan; Wilson, Jane


    Using results from a survey of British graduates, examined outcomes of higher education for older students, including their current employment situation, relationship of degree to job, and student satisfaction. Found that mature students are an extremely heterogeneous group, with differences in outcomes by age and mode of study. (EV)

  5. Earnings Returns to the British Education Expansion (United States)

    Devereux, Paul J.; Fan, Wen


    We study the effects of the large expansion in British educational attainment that took place for cohorts born between 1970 and 1975. Using the Quarterly Labour Force Survey, we find that the expansion caused men to increase education by about a year on average and gain about 8% higher wages; women obtained a slightly greater increase in education…

  6. British Technology Education. An American View. (United States)

    Hutchinson, John


    The author describes the British Craft, Design and Technology (CDT) curriculum, which is comparable to American technology education. According to the author, CDT is characterized by creative thinking and experimentation. He states, however, that little national coordination or cooperation is evident. (CH)

  7. Considerations for Education Reform in British Columbia (United States)

    Santos, Ana


    Countries around the world refer to twenty-first century education as essential to maintaining personal and national economic advantage and draw on this discourse to advocate for and embark on educational reform. This paper examines issues around education reform, particularly in British Columbia. It argues that reformers should give careful…

  8. British physics Newton's law of funding

    CERN Multimedia


    In Britain, fundamental physics is in a pickle ISAAC NEWTON, besides being the founder of modern physics, was also master of Britain's mint. That is a precedent which many British physicists must surely wish had become traditional. At the moment, money for physics is in short supply in Britain.

  9. British used Congreve Rockets to Attack Napoleon (United States)


    Sir William Congreve developed a rocket with a range of about 9,000 feet. The incendiary rocket used black powder, an iron case, and a 16-foot guide stick. In 1806, British used Congreve rockets to attack Napoleon's headquarters in France. In 1807, Congreve directed a rocket attack against Copenhagen.

  10. British scorched earth and concentration camp policies.

    African Journals Online (AJOL)


    THE BRITISH SCORCHED EARTH AND. CONCENTRATION CAMP POLICIES IN THE. POTCHEFSTROOM REGION, 1899–1902. 1. Prof GN van den Bergh. Research Associate, North-West University. Abstract. The continued military resistance of the Republics after the occupation of. Bloemfontein and Pretoria and ...

  11. Spitsbergen - Imperialists beyond the British Empire

    NARCIS (Netherlands)

    Kruse, Frigga; Hacquebord, Louwrens


    This paper looks at the relationship between Spitsbergen in the European High Arctic and the global British Empire in the first quarter of the twentieth century. Spitsbergen was an uninhabited no man's land and comprised an unknown quantity of natural resources. The concepts of geopolitics and New

  12. Telephone Operators' Resistance to British Colonial Administration ...

    African Journals Online (AJOL)

    This paper aims to write the history of yet another form of resistance to colonial rule in British Africa with a focus on telephone operators in the erstwhile Cameroons Province. The pith and kernel of the paper therefore is to show how telephone operators resisted the colonial administration. This typology of resistance is yet to ...

  13. The Royal Navy and British Security Policy. (United States)


    development or production. To Kennedy and MacNamara , the decision to cancel the SKYBOLT program in 1962 was only a measure to improve the cost...Kennedy- MacNamara decision to cancel SKYBOLT. Kennedy suc- cessfully solved the British dilemma by offering to sell them the American POLARIS submarine

  14. Demand for wildlife hunting in British Columbia

    NARCIS (Netherlands)

    Sun, L.; Kooten, van G.C.; Voss, G.M.


    We present estimates of the demand for hunting licenses by residents and nonresidents in British Columbia for the period 19712000. We obtain estimates of both short-run and long-run price elasticities and discuss their revenue implications for future fee increases. We find the demand by nonresidents

  15. HIV Prevalence among Aboriginal British Columbians

    Directory of Open Access Journals (Sweden)

    Strathdee Steffanie


    Full Text Available Abstract Context There is considerable concern about the spread of HIV disease among Aboriginal peoples in British Columbia. Objective To estimate the number of Aboriginal British Columbians infected with HIV. Design and setting A population-based analysis of Aboriginal men and women in British Columbia, Canada from 1980 to 2001. Participants Epidemic curves were fit for gay and bisexual men, injection drug users, men and women aged 15 to 49 years and persons over 50 years of age. Main outcome measures HIV prevalence for the total Aboriginal population was modeled using the UNAIDS/WHO Estimation and Projection Package (EPP. Monte Carlo simulation was used to estimate potential number infected for select transmission group in 2001. Results A total of 170,025 Aboriginals resided in British Columbia in 2001, of whom 69% were 15 years and older. Of these 1,691 (range 1,479 – 1,955 men and women aged 15 years and over were living with HIV with overall prevalence ranging from 1.26% to 1.66%. The majority of the persons infected were men. Injection drug users (range 1,202 – 1,744 and gay and bisexual men (range 145, 232 contributed the greatest number of infections. Few persons infected were from low risk populations. Conclusion More than 1 in every 100 Aboriginals aged 15 years and over was living with HIV in 2001. Culturally appropriate approaches are needed to tailor effective HIV interventions to this community.

  16. Drivers of Cousin Marriage among British Pakistanis (United States)

    Shaw, Alison


    Background/Aim Why has the apparently high rate of cousin marriage among Bradford Pakistanis been sustained, 50 years since Pakistani migration to Britain began? Methods A review of the anthropological literature on Pakistani migration and settlement, British Pakistani marriage patterns and the phenomenon of transnational marriage. Results British Pakistanis are diverse in regional origins and social class characteristics, with many Bradford Pakistanis originating from the Mirpur district and northern Punjab. British Pakistani marriages often involve a partner from Pakistan who joins a spouse in the UK. Transnational marriage of first cousins offers relatives in Pakistan opportunities for a ‘better’ life in the West and are important for British Pakistanis for economic, social, cultural and emotional reasons. These processes are also differentially influenced by region of origin and class characteristics in Pakistan as well as by education, employment and locality in Britain. The pattern observed in Bradford may not be applicable nationally. Conclusion Further research examining marital decisions over several generations in families differing by social class, region of origin in Pakistan and locality in Britain is necessary to contextualise the findings from Bradford. PMID:25060267

  17. Four former British mining settlements on Spitsbergen

    NARCIS (Netherlands)

    Kruse, Frigga; Claughton, P.; Mills, C.


    The LASHIPA project participated in the recent International Polar Year to evaluate the large-scale historical exploitation of polar areas. This sub-project looks at the role of British actors in the economic and geopolitical development of the European High Arctic during the early twentieth

  18. African Centered Knowledge: A British Perspective. (United States)

    Christian, Mark


    Considers the impact of African centered knowledge within the United Kingdom. Recent development of African Diaspora studies has forged links between various black Atlantic communities. The United Kingdom has experienced positive grassroots community response to the work of noted African centered scholars, yet within the British academy,…


    Directory of Open Access Journals (Sweden)

    Natalia Valerievna Eremina


    Full Text Available The aim of the article is to reveal the forms, methods, content of British strategy in Arctic. Arctic is becoming the area of international cooperation among, first of all, Arctic states. Britain has ambitions to get the status of so-called “subarctic state” to prove its international leadership and acquire guarantees of energetic security. Now Britain has been elaborating the two strategies: military and scientific ones. The main instrument to solve the tasks for Britain is to participate in international structures, connected with Arctic. The article pays attention to the aspects that were not previously analyzed, such as: reasons of British interests in Arctic, bilateral and multilateral relationships between Britain and its partners, first of all, cooperation between Russia and Britain; British institutions; positive and negative aspects of British Arctic strategy; factors that have impact on its evolution, mainly EU and Scottish factors. The research allowed to make the conclusion that Britain does not have enough instruments to have a strong disposition in Arctic, though it plans to accelerate its participation in Arctic organizations. The article is based upon system and structural analysis.

  20. subordination across ghanaian and british newspaper editorials

    African Journals Online (AJOL)

    Empirical research in this area is scanty, though this theoretical argumentation is not without contention, especially cross-culturally. Empirical investigation is therefore ... Frimpong: Subordination Across Ghanaian and British Newspaper Editorials: A Register. Perspective. 78. Figure 1: The Components in a register analysis.

  1. Industrial applications of electron accelerators

    CERN Document Server

    Cleland, M R


    This paper addresses the industrial applications of electron accelerators for modifying the physical, chemical or biological properties of materials and commercial products by treatment with ionizing radiation. Many beneficial effects can be obtained with these methods, which are known as radiation processing. The earliest practical applications occurred during the 1950s, and the business of radiation processing has been expanding since that time. The most prevalent applications are the modification of many different plastic and rubber products and the sterilization of single-use medical devices. Emerging applications are the pasteurization and preservation of foods and the treatment of toxic industrial wastes. Industrial accelerators can now provide electron energies greater than 10 MeV and average beam powers as high as 700 kW. The availability of high-energy, high-power electron beams is stimulating interest in the use of X-rays (bremsstrahlung) as an alternative to gamma rays from radioactive nuclides.

  2. Some Tribological Characterization of “EPDM” Rubber

    Directory of Open Access Journals (Sweden)

    A. Mukhopadhyay


    Full Text Available Ethylene Propylene Diene Monomer (EPDM rubber emerges as a dominant elastomer for major engineering applications. The major properties of EPDM are its outstanding heat, ozone and weather resistance ability. It has a good resistance to polar substances and steam condition too. In automobiles EPDM rubber has a common use as seals. This includes door seals, window seals, trunk seals and sometimes hood seals. Frequently these seals are the source of noise due to the movement of the door versus the car body. This is due to friction between the EPDM rubber parts and the mating surfaces. Thus, the contact iteration between the rubber sealing and the indenting object must be known to optimize the performance of rubber sealing. However, it is need less to mention that the behaviour of any viscoelastic material is very difficult to be predicted. In the present work various tribo-characteristics of EPDM rubber of different hardness have been evaluated utilizing the available laboratory test facilities in the Jadavpur University, Kolkata, India. Compression tests have been carried out using ‘Instron’ to determine the flow behaviour of EPDM rubber of different hardness both in dry as well as under different conditions of lubrication. The flow behaviour like load -vs.- elongation curves, true stress -vs.- elongation curves and true stress -vs.- true strain curves have been drawn from the experimental data. Abrasive wear behaviour has been evaluated using a two-body abrasion tester and the pattern abrasion has been appraised through SEM/EDAX study. Experimental results reveal that the hardness of EPDM rubber has significant effect on the flow behaviour and wear characteristics. The hardness, again, depends on the proportion of carbon black (CB content. Thus it can be stated that the flow behaviour can be governed by controlling the CB concentration in the EPDM rubber. Based on the experimental results conclusion has been drawn accordingly. Some of the

  3. The phenology pattern of rubber trees in plantation and its impacts on rubber tree structure, water and carbon cycles (United States)

    Liu, W.; Giambelluca, T. W.; Mudd, R. G.


    Commercial rubber (Hevea Brasiliensis) is originally native to the Amazon rainforest and it has become one of the important commercial crops in Mainland Southeast Asia. Similarly to some trees species in Amazon but quite distinctly from other native forests in Southeast Asia, rubber tree sheds its leaves in the middle of dry season and flushes new leaves before the onset of the wet season. Moreover, the mountane mainland Southeast Asia is heavily influenced by the monsoon climate which has most the precipitation in the wet season while almost no rainfall in the dry season. It is believed that the phenology pattern of rubber interacted with local climate would not only regulate the seasonal rubber plantation structures but also further alter the local energy and water budget. However, it is still lack of solid understandings of how the phenology patterns in terms of the leaf area index (LAI) changes of the rubber tree response to environmental drivers. The study tries to shed lights on the issue from analyses of a various types of in-situ field data combined with 3 years' tower flux measurements collected within the rubber plantations. It concludes that: 1) Both the monthly tree height increment and the monthly biomass accumulation are highly correlated with the LAI changes, which have the low rate of changes in the dry season versus the relative high rate of changes in the wet season; 2) the daily evapotranspiration (ET) of the rubber tree is very sensitive to the daily LAI changes in the dry season (R2 > 0.9); 3) the LAI changes, especially the leaf drops, are majorly determined by the accumulated precipitation in the past three months.

  4. Microclimate and development of 'Conilon' coffee intercropped with rubber trees

    Directory of Open Access Journals (Sweden)

    Fábio Luiz Partelli


    Full Text Available The objective of this work was to evaluate the influence of intercropping 'Conilon' coffee (Coffea canephora with rubber trees on coffee tree microclimate, nutrition, growth, and yield. Rubber trees were planted in two double rows 33 m apart, with 4x2.3 m spacing between plants. Treatments consisted of the distances from the coffee plants to the rubber trees: 3, 6, 9, 12, and 15 m. Measurements of atmospheric variables (temperature, irradiance, and relative humidity, leaf nutrient concentration, internode length of plagiotropic and orthotropic branches, individual leaf area, chlorophyll content, and yield were performed. Intercropping promotes changes in the microclimatic conditions of coffee plants close to rubber trees, with reduction of temperature and irradiance level and increase in air relative humidity. The proximity of the coffee tree to the rubber trees promotes the elongation of the plagiotropic and orthotropic branches and increases the individual leaf area; however, it does not affect leaf concentrations of N, K, Mg, Fe, Zn, and B in 'Conilon' coffee and does not have a negative impact on yield.

  5. Natural Rubber Nanocomposite with Human-Tissue-Like Mechanical Characteristic (United States)

    Murniati, Riri; Novita, Nanda; Sutisna; Wibowo, Edy; Iskandar, Ferry; Abdullah, Mikrajuddin


    The blends of synthetic rubber and natural rubber with nanosilica were prepared using a blending technique in presence of different filler volume fraction. The effect of filler on morphological and mechanical characteristics was studied. Utilization of human cadaver in means of medical study has been commonly used primarily as tools of medical teaching and training such as surgery. Nonetheless, human cadaver brought inevitable problems. So it is necessary to find a substitute material that can be used to replace cadavers. In orthopaedics, the materials that resemble in mechanical properties to biological tissues are elastomers such as natural rubber (latex) and synthetic rubber (polyurethanes, silicones). This substitution material needs to consider the potential of Indonesia to help the development of the nation. Indonesia is the second largest country producer of natural rubber in the world. This paper aims to contribute to adjusting the mechanical properties of tissue-mimicking materials (TMMs) to the recommended range of biological tissue value and thus allow the development of phantoms with greater stability and similarity to human tissues. Repeatability for the phantom fabrication process was also explored. Characteristics were then compared to the control and mechanical characteristics of different human body part tissue. Nanosilica is the best filler to produce the best nanocomposite similarities with human tissue. We produced composites that approaching the properties of human internal tissues.

  6. Nutrient cycling in a RRIM 600 clone rubber plantation

    Directory of Open Access Journals (Sweden)

    Murbach Marcos Roberto


    Full Text Available Few reports have been presented on nutrient cycling in rubber tree plantations (Hevea brasiliensis Muell. Arg.. This experiment was carried out to evaluate: the effect of K rates on the amount of nutrients transfered to the soil in a 13-year old Hevea brasilensis RRIM 600 clone plantation, nutrient retranslocation from the leaves before falling to the soil, and nutrient loss by dry rubber export. The experiment started in 1998 and potassium was applied at the rates of 0, 40, 80 and 160 kg ha-1 of K2O under the crowns of 40 rubber trees of each plot. Literfall collectors, five per plot, were randomly distributed within the plots under the trees. The accumulated literfall was collected monthly during one year. The coagulated rubber latex from each plot was weighed, and samples were analyzed for nutrient content. Increasing K fertilization rates also increased the K content in leaf literfall. Calcium and N were the most recycled leaf nutrients to the soil via litterfall. Potassium, followed by P were the nutrients with the highest retranslocation rates. Potassium was the most exported nutrient by the harvested rubber, and this amount was higher than that transfered to the soil by the leaf literfall.

  7. RTV Silicone Rubber Degradation Induced by Temperature Cycling

    Directory of Open Access Journals (Sweden)

    Xishan Wen


    Full Text Available Room temperature vulcanized (RTV silicone rubber is extensively used in power system due to its hydrophobicity and hydrophobicity transfer ability. Temperature has been proven to markedly affect the performance of silicone rubbers. This research investigated the degradation of RTV silicone rubber under temperature cycling treatment. Hydrophobicity and its transfer ability, hardness, functional groups, microscopic appearance, and thermal stability were analyzed using the static contact angle method, a Shore A durometer, Fourier transform infrared spectroscopy (FTIR, scanning electron microscopy (SEM, and thermogravimetry (TG, respectively. Some significant conclusions were drawn. After the temperature was cycled between −25 °C and 70 °C, the hydrophobicity changed modestly, but its transfer ability changed remarkably, which may result from the competition between the formation of more channels for the transfer of low molecular weight (LMW silicone fluid and the reduction of LMW silicone fluid in the bulk. A hardness analysis and FTIR analysis demonstrated that further cross-linking reactions occurred during the treatment. SEM images showed the changes in roughness of the RTV silicone rubber surfaces. TG analysis also demonstrated the degradation of RTV silicone rubber by presenting evidence that the content of organic materials decreased during the temperature cycling treatment.

  8. Thermoreversibly Cross-Linked EPM Rubber Nanocomposites with Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Lorenzo Massimo Polgar


    Full Text Available Conductive rubber nanocomposites were prepared by dispersing conductive nanotubes (CNT in thermoreversibly cross-linked ethylene propylene rubbers grafted with furan groups (EPM-g-furan rubbers. Their features were studied with a strong focus on conductive and mechanical properties relevant for strain-sensor applications. The Diels-Alder chemistry used for thermoreversible cross-linking allows for the preparation of fully recyclable, homogeneous, and conductive nanocomposites. CNT modified with compatible furan groups provided nanocomposites with a relatively large tensile strength and small elongation at break. High and low sensitivity deformation experiments of nanocomposites with 5 wt % CNT (at the percolation threshold displayed an initially linear sensitivity to deformation. Notably, only fresh samples displayed a linear response of their electrical resistivity to deformations as the resistance variation collapsed already after one cycle of elongation. Notwithstanding this mediocre performance as a strain sensor, the advantages of using thermoreversible chemistry in a conductive rubber nanocomposite were highlighted by demonstrating crack-healing by welding due to the joule effect on the surface and the bulk of the material. This will open up new technological opportunities for the design of novel strain-sensors based on recyclable rubbers.

  9. Vulcanization Kinetics of Natural Rubber Based On Free Sulfur Determination

    Directory of Open Access Journals (Sweden)

    Abu Hasan


    Full Text Available The determination of free sulfur in the rubber vulcanizates provided significant representation of vulcanization reaction. In this research, the effects of vulcanization temperature, the mixing method of carbon black into rubber, the ingredients mixing sequence and the type of carbon black were studied on masticated and milled natural rubber in which the reaction was observed by un-reacted sulfur determination. The results showed that higher vulcanization temperature provided faster vulcanization reaction and greater reaction rate constant. Similarly, the mixing sequence of ingredient and carbon black into rubber influenced the rate of vulcanization reaction. The subsequent ingredients mixing sequence, in this case, resulted in higher vulcanization rate compared to that of the simultaneous one. However, the mixing method of carbon black into rubber brought small effect on the rate of vulcanization reaction. The type of carbon black applied was observed to influence the reaction rate of vulcanization. Smaller particle sizes of carbon black gave larger reaction rate constant. In this case, the type of carbon black N 330 gave faster vulcanization rate than that of N 660.

  10. Recycling of chlorobutyl rubber compounds subjected of gamma radiation; Reciclagem de compostos de borracha clorobutilinica por meio de radiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Scagliusi, Sandra R.; Cardoso, Elizabeth C.L.; Santos, Renato G. dos; Lugao, Ademar B., E-mail: [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)


    In Brazil, as in the world, the correct destination of solid waste and its impacts on the environment are so worrying that have been treated as public policy of the State, leading to behavioral change on the part of business and society. Polymeric materials (plastics and rubbers) comprise a growing proportion of urban and industrial waste sent to landfills. Development of technologies for reducing polymeric residues that are acceptable from an environmental point of view, and which are effective in terms of cost, has proven a difficult challenge due to the inherent complexities of all reuse polymers. To establish more efficient processes for reuse / recycling of polymeric materials remains a challenge throughout the world. Due to ionizing radiation ability to alter the structure and properties of materials and the fact that it is applicable to all types of polymers, irradiation is promising and effective for the management of solid waste which can be used as raw materials or additives chemicals. Halogenated polymers have been used on a large scale in a broad variety of applications, such as tires, spare parts (tubes, tire liners, etc.) and various artifacts (covers, gaskets, etc.). Due to the low unsaturation of chlorobutyl rubber (about 3%), shows significant levels of degradation upon exposure to radiation. The main effect of gamma rays on butyl polymers is the formation of free radicals and the chain scission. This paper aims to introduce a rubber recovery technique chlorobutyl rubber the characterization of non-irradiated and irradiated samples based on the following properties: tensile strength and elongation at break, hardness, and rheological properties. The radiation doses used in the study were degradation range: 0 kGy, 25 kGy, 50 kGy, 100 kGy, 150 kGy and 200 kGy, in order to confirm the feasibility of recycling chlorobutyl rubber. It was observed that doses greater than 100 kGy, the material exhibits a high degree of degradation. Research on rubber

  11. Parametric study and shrinkage modelling of natural rubber sheet drying using COMSOL multiphysics (United States)

    Ajani, C.; Kumar, A.; Curcio, S.; Tekasakul, P.


    Natural rubber is one of the major exporting cash crops in Thailand. Shrinkage in natural rubber sheet during drying creates uneven stresses in the rubber, hampers the quality and the water activity predisposes it to microbial activation. Hence, the effect of drying parameters on shrinkage has been considered in this work. The finite element concept coupled with the arbitrary Lagrangian-Eulerian (ALE) method was used to solve the two-dimensional coupled physics in the rubber sheet drying chamber and account for the shrinkage effect. The spatial domain (drying chamber), material domain (rubber sheet) was analysed. An isotropic linear elastic model was assumed for the rubber sheet for analysis. Three Case studies of different velocity, temperature, relative humidity and shrinkage coefficient were considered in the numerical study using COMSOL Multiphysics. It is concluded that increase in the operating parameters increases the shrinkage of the rubber. Therefore, rubber should dry at relatively lower operating parameters to improve its quality.

  12. 75 FR 17827 - Goodyear Tire & Rubber Company, Grant of Petition for Decision of Inconsequential Noncompliance (United States)


    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION National Highway Traffic Safety Administration Goodyear Tire & Rubber Company, Grant of Petition for Decision of Inconsequential Noncompliance Goodyear Tire & Rubber Company (Goodyear), has determined that...

  13. Nanolipoprotein particles comprising a natural rubber biosynthetic enzyme complex and related products, methods and systems

    Energy Technology Data Exchange (ETDEWEB)

    Hoeprich, Paul D.; Whalen, Maureen


    Provided herein are nanolipoprotein particles that comprise a biosynthetic enzyme more particularly an enzyme capable of catalyzing rubber or other rubbers polymerization, and related assemblies, devices, methods and systems.

  14. Optimization of carbon black loading in compounding of natural rubber by unique cross point technique

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Bong Young [Kumho Technical R and D Center (Korea, Republic of); Park, Chan Young [Chonnam National Univ., Kwangju (Korea, Republic of)


    The unique Cross Point technique, offering uniquely the optimum loading of carbon blacks a reinforcing filler required in rubber compounds tire industry, has been proposed. The strength of the technique lies in optimizing the feasible loading by both Mooney viscosity and DSR(Dynamic Stress Relaxometer) simultaneously. In this study, the Mooney viscosity(ML1 + 4,125 degree){sub {eta}x} as a function of its loading X and characteristic value {gamma} was expressed as {eta}{sub x} = {eta}{sub 0}{center_dot}{gamma}{center_dot}(1 + a{sub 1}X + a{sub 2}X{sup 2}). And also Sr`, the relative integral in two seconds of torque from DSR, was a function of X as follow Sr` = b{sub 0} + b{sub 1}X. After thermal cure the natural rubber compounds loaded with the quantity designated by the cross section of the above two equations showed so feasible properties confirmed by tensile tester, Pico abrasion tester and Flexometer that the experimental coefficients of the equations applicable to fields are listed in Table 2. 12 refs., 4 tabs., 11 figs.

  15. Cultural and age differences in beliefs about depression: British Bangladeshis vs. British Whites


    McClelland, A.; S. Khanam; Furnham, A.


    This study examines beliefs about depression as a function of ethnic background (British Bangladeshis vs. British Whites) and age. A total of 364 participants completed a 65-item questionnaire, containing general questions regarding depression and anti-depressive behaviour; the causes of depression, and treatments for depression. The hypotheses were broadly supported; there were significant interactions between ethnicity and age, which generally revealed an increasingly negative attitude towa...

  16. Colonization and Community: the Vancouver Island coalfield and the making of the British Columbian working class

    Energy Technology Data Exchange (ETDEWEB)

    John Douglas Belshaw [University College of the Cariboo, Kamloops, BC (Canada). Department of Philosophy, History, and Politics


    In the nineteenth century coal-miners imported from Europe, Asia, and eastern North America burrowed beneath the Vancouver Island towns of Nanaimo, Wellington, and Cumberland. The book looks at British Columbia's first working class, the men, women, and children beneath and beyond the pit-head. Beginning with an exploration of emigrant expectations and ambitions, it investigates working conditions, household wages, racism, industrial organization, gender, schooling, leisure, community building, and the fluid identity of the British mining colony, the archetypal west coast proletariat. By connecting the story of Vancouver Island to the larger story of Victorian industrialization, the author delineates what was distinctive and what was common about the lot of the settler society.

  17. Behaviour model identification based on inverse modeling and using Optical Full Field Measurements (OFFM): application on rubber and steel (United States)

    Velay, V.; Robert, L.; Schmidt, F.; Hmida, S.; Vallet, T.


    Biaxial properties of materials (polymer or steel) used in many industrial processes are often difficult to measure. However, these properties are useful for the numerical simulations of plastic-processing operations like blow moulding or thermoforming for polymers and superplastic forming or single point incremental forming for steels. Today, Optical Full Field Measurements (OFFM) are promising tools for experimental analysis of materials. Indeed, they are able to provide a very large amount of data (displacement or strain) spatially distributed. In this paper, a mixed numerical and experimental investigation is proposed in order to identify multi-axial constitutive behaviour models. The procedure is applied on two different materials commonly used in forming processes: polymer (rubber in this first approach) and steel. Experimental tests are performed on various rubber and steel structural specimens (notched and open-hole plate samples) in order to generate heterogeneous displacement field. Two different behaviour models are considered. On the one hand, a Money-Rivlin hyperelastic law is investigated to describe the high levels of strain induced in tensile test performed on a rubber open-hole specimen. On the other hand, Ramberg-Osgood law allows to reproduce elasto-plastic behaviour of steel on a specimen that induces heterogeneous strain fields. Each parameter identification is based on a same Finite Element Model Updated (FEMU) procedure which consists in comparing results provided by the numerical simulation (ABAQUS™) with full field measurements obtained by the DISC (Digital Image Stereo-Correlation) technique (Vic-3D®).

  18. Effect of personal risk factors on the prevalence rate of musculoskeletal disorders among workers of an Iranian rubber factory. (United States)

    Samaei, S E; Tirgar, A; Khanjani, N; Mostafaee, M; Bagheri Hosseinabadi, M


    Musculoskeletal Disorders (MSDs) are among the most common occupational disorders in many countries and have an increasing trend. The present study was conducted in order to determine the prevalence rate of MSDs in different body regions and the effect of personal factors on the prevalence rate of MSDs among rubber industry workers. This analytical and cross-sectional study was performed on 206 workers of an Iranian rubber factory in 2014. The samples were randomly selected. Data were gathered by means of personal information form, the Nordic Musculoskeletal Questionnaire (NMQ) and the Rapid Entire Body Assessment (REBA). The results were analyzed using SPSS16; by descriptive and analytical statistics. The mean age and work history of subjects were 34.54±6.36 and 12.34±6.28 years, respectively. The highest prevalence rate of MSDs in the last twelve-months was related to the lower back region with a prevalence rate of 62.1%. Based on logistic regression, a significant correlation was found between MSDs and the final REBA score so that for a one-unit increase in score, the risk or complaint of neck and low back pain increased by 48.5% and 37.1%, respectively. Many rubber factory workers experience MSDs especially in the lower back region as a consequence of occupational risk factors. Therefore, detecting the occupational risk factors, work position standards and following ergonomic interventions are highly recommended.

  19. A Review on Using Crumb Rubber in Reinforcement of Asphalt Pavement


    Nuha Salim Mashaan; Asim Hassan Ali; Mohamed Rehan Karim; Mahrez Abdelaziz


    An immense problem affecting environmental pollution is the increase of waste tyre vehicles. In an attempt to decrease the magnitude of this issue, crumb rubber modifier (CRM) obtained from waste tyre rubber has gained interest in asphalt reinforcement. The use of crumb rubber in the reinforcement of asphalt is considered as a smart solution for sustainable development by reusing waste materials, and it is believed that crumb rubber modifier (CRM) could be an alternative polymer material in i...

  20. Study on Load-displacement Test of Rubber Pads of Coal Mine Roadway Constructed by Shield (United States)

    Yang, Yue; Chen, Xiaoguo; Yang, Liyun


    Shield method construction of coal mine roadway is the future trend of the development of deep coal mining. The main shaft supporting is the segment. There is rubber pads between segment and segment. The performance of compression deformation of rubber pad is essential for the overall stability of lining. Through load test, displacement of the rubber pad under load, the thrust force law of the rubber pad deformation, and provide a theoretical basis for the stability analysis of coal mine tunnel shield construction.