WorldWideScience

Sample records for reaction conditions employed

  1. Employment status and working conditions

    NARCIS (Netherlands)

    Goudswaard, A.; Andries, F.

    2002-01-01

    In the 1990s an increasing number of employees were engaged in non-permanent contract work in the European Union. This can, to a large extent, be explained by an active labour market policy where job creation was the focus, and this type of employment provided a way of meeting the increased demand

  2. EU hotel and restaurant sector : work and employment conditions

    NARCIS (Netherlands)

    Klein Hesselink, J.; Houtman, I.; Berg, R. van den; Bossche, S. van den; Heuvel, F. van den

    2004-01-01

    In 2000, the European Foundation for the Improvement of Living and Working Conditions (the Foundation) carried out the third European Survey on Working Conditions. In that survey, information was collected on the working conditions, health and wellbeing of employed and self-employed persons in the

  3. Photogeochemical reactions of manganese under anoxic conditions

    Science.gov (United States)

    Liu, W.; Yee, N.; Piotrowiak, P.; Falkowski, P. G.

    2017-12-01

    Photogeochemistry describes reactions involving light and naturally occurring chemical species. These reactions often involve a photo-induced electron transfer that does not occur in the absence of light. Although photogeochemical reactions have been known for decades, they are often ignored in geochemical models. In particular, reactions caused by UV radiation during an ozone free early Earth could have influenced the available oxidation states of manganese. Manganese is one of the most abundant transition metals in the crust and is important in both biology and geology. For example, the presence of manganese (VI) oxides in the geologic record has been used as a proxy for oxygenic photosynthesis; however, we suggest that the high oxidation state of Mn can be produced abiotically by photochemical reactions. Aqueous solutions of manganese (II) as well as suspensions of rhodochrosite (MnCO3) were irradiated under anoxic condition using a 450 W mercury lamp and custom built quartz reaction vessels. The photoreaction of the homogeneous solution of Mn(II) produced H2 gas and akhtenskite (ɛ-MnO2) as the solid product . This product is different than the previously identified birnessite. The irradiation of rhodochrosite suspensions also produced H2 gas and resulted in both a spectral shift as well as morphology changes of the mineral particles in the SEM images. These reactions offer alternative, abiotic pathways for the formation of manganese oxides.

  4. EU road freight transport sector : work and employment conditions

    NARCIS (Netherlands)

    Houtman, I.L.D.; Klein Hesselink, D.J.; Bossche, S.N.J. van den; Berg, R. van der; Heuvel, F. van den

    2004-01-01

    International competition and technological developments have had both positive and negative effects on the road freight transport sector. These changes have significantly influenced work and employment conditions in the sector. As this report highlights, creating more and better jobs while

  5. Terms and Conditions of Self-Employment: A Gender Perspective

    OpenAIRE

    Mångs, Andreas

    2012-01-01

    In this paper we present a detailed description of the survey “How does your life puzzle work?” that was performed in 2009. The survey’s primary purpose was to provide information about the terms and conditions in self-employment relative to wage-employment and about the reasons for taking up self-employment. In addition, the survey included questions related to social background and socio-economic characteristics of self-employed. We report some of the findings from the survey regarding work...

  6. Presenteeism among self-employed workers: Korean working conditions survey.

    Science.gov (United States)

    Kim, Min-Su; Park, Jae Bum; Min, Kyoung-Bok; Lee, Kyung-Jong; Kwon, Kimin

    2014-01-01

    Presenteeism has become a public concern recently. Thus, we aimed to understand the relationship between self-employed workers and presenteeism using a nationally representative sample of Korean workers. Using data from the Korean Working Conditions Survey conducted in 2011, a total of 43,392 workers including paid employees and self-employed workers were analyzed. The effect of employment status on presenteeism was analyzed using logistic regression analysis. The independent variables were socioeconomic characteristics, working conditions, and working environments. Among the 43,392 workers, 34,783 were paid and 8,609 were self-employed. Self-employed workers were more likely to exhibit presenteeism than were paid workers. An elevated odds ratio of 1.27 (95% CI 1.19-1.36) was found for presenteeism among self-employed workers. Being self-employed was significantly related with exhibiting presenteeism. Additional research should investigate whether other factors mediate the relationship between employment status and presenteeism as well as ways to reduce presenteeism among self-employed workers.

  7. Flexible employment policies and working conditions: the Netherlands

    NARCIS (Netherlands)

    Klein Hesselink, D.J.; Miedema, E.; Goudswaard, A.; Kraan, K.O.

    2000-01-01

    The European Foundation for the Improvement of Living and Working Conditions has commissioned a research project to analyse the impact of flexible employment policies and human resources management on working conditions at the corporate level. Research institutes of seven countries participate in

  8. 76 FR 44265 - General Working Conditions in Shipyard Employment; Correction

    Science.gov (United States)

    2011-07-25

    ... DEPARTMENT OF LABOR Occupational Safety and Health Administration 29 CFR Part 1910 [Docket No. OSHA-S049-2006-0675 (Formerly Docket No. S-049)] RIN 1218-AB50 General Working Conditions in Shipyard... on General Working Conditions in Shipyard Employment published in the Federal Register of May 2, 2011...

  9. Ergonomic intervention for employed persons with rheumatic conditions.

    Science.gov (United States)

    Allaire, Saralynn J; Backman, Catherine L; Alheresh, Rawan; Baker, Nancy A

    2013-01-01

    Prior articles in this series on employment and arthritis have documented the major impact arthritis and other rheumatic conditions have on employment. As expected, physically demanding job tasks, including hand use, are substantial risk factors for work limitation. Computer use has been increasing. People with arthritis may choose occupations involving extensive computer use to avoid occupations with other physical demands. But studies show many people with arthritis conditions have difficulty using computers.Ergonomic assessment and implementation helps relieve the physical and other demands of jobs. The Ergonomic Assessment Tool for Arthritis (EATA) is specifically for people with arthritis conditions. Since the EATA can be conducted off worksite, it is feasible to use with workers not wishing to disclose their condition to their employer. Available research supports the effectiveness of ergonomic intervention as a viable method to reduce work limitation for persons with arthritis. Some workers will need additional vocational intervention to remain employed long term. However, ergonomic intervention is a useful first step, as it promotes awareness of arthritis effects on work activities. Assisting workers with arthritis or other rheumatic conditions to use ergonomics to enhance their ability to work well should be an important aspect of managing these conditions.

  10. Biogeochemical Reactions Under Simulated Europa Ocean Conditions

    Science.gov (United States)

    Amashukeli, X.; Connon, S. A.; Gleeson, D. F.; Kowalczyk, R. S.; Pappalardo, R. T.

    2007-12-01

    Galileo data have demonstrated the probable presence of a liquid water ocean on Europa, and existence of salts and carbon dioxide in the satellite's surface ice (e.g., Carr et al., 1998; McCord et al., 1999, Pappalardo et al., 1999; Kivelson et al., 2000). Subsequently, the discovery of chemical signatures of extinct or extant life in Europa's ocean and on its surface became a distinct possibility. Moreover, understanding of Europa's potential habitability is now one of the major goals of the Europa Orbiter Flagship mission. It is likely, that in the early stages of Europa's ocean formation, moderately alkaline oceanic sulfate-carbonate species and a magnetite-silicate mantel could have participated in low-temperature biogeochemical sulfur, iron and carbon cycles facilitated by primitive organisms (Zolotov and Shock, 2004). If periodic supplies of fresh rock and sulfate-carbonate ions are available in Europa's ocean, then an exciting prospect exists that life may be present in Europa's ocean today. In our laboratory, we began the study of the plausible biogeochemical reactions under conditions appropriate to Europa's ocean using barophilic psychrophilic organisms that thrive under anaerobic conditions. In the near absence of abiotic synthetic pathways due to low Europa's temperatures, the biotic synthesis may present a viable opportunity for the formation of the organic and inorganic compounds under these extreme conditions. This work is independent of assumptions regarding hydrothermal vents at Europa's ocean floor or surface-derived oxidant sources. For our studies, we have fabricated a high-pressure (5,000 psi) reaction vessel that simulates aqueous conditions on Europa. We were also successful at reviving barophilic psychrophilic strains of Shewanella bacterium, which serve as test organisms in this investigation. Currently, facultative barophilic psychrophilic stains of Shewanella are grown in the presence of ferric food source; the strains exhibiting iron

  11. Applying reaction condition index to predict sandstone type uranium deposit

    International Nuclear Information System (INIS)

    Chen Gongxin; Liu Jinhui; Cheng Hai

    2002-01-01

    On the basic of the explanation of reaction condition index, the deduction of reaction condition index calculation principle, the hydrogeological setting in Gongpoquan basin in Baishan, Gansu province and the study of reaction condition index of its water source point, the north Luotuoquan area in Gongpoquan basin seems to be a favourable place for sandstone type uranium deposit, and the prospect area for sandstone type uranium deposit is delimitated

  12. Individual employment contract - the fundamental condition of legal labour relations

    Directory of Open Access Journals (Sweden)

    Nicolae ROMANDAŞ

    2017-03-01

    Full Text Available This article contains the description and analysis of the most important institution of labour law – the individual employment contract. At the same time, we analyze the nature of the individual employment contract, the instruments that should be concluded by employers according to the labour law. Also, the article describes the main doctrinal opinions that ware used to elucidate the concept of the individual employment contract.

  13. The Eschenmoser coupling reaction under continuous-flow conditions

    Science.gov (United States)

    Singh, Sukhdeep; Köhler, J Michael; Schober, Andreas

    2011-01-01

    Summary The Eschenmoser coupling is a useful carbon–carbon bond forming reaction which has been used in various different synthesis strategies. The reaction proceeds smoothly if S-alkylated ternary thioamides or thiolactames are used. In the case of S-alkylated secondary thioamides or thiolactames, the Eschenmoser coupling needs prolonged reaction times and elevated temperatures to deliver valuable yields. We have used a flow chemistry system to promote the Eschenmoser coupling under enhanced reaction conditions in order to convert the demanding precursors such as S-alkylated secondary thioamides and thiolactames in an efficient way. Under pressurized reaction conditions at about 220 °C, the desired Eschenmoser coupling products were obtained within 70 s residence time. The reaction kinetics was investigated and 15 examples of different building block combinations are given. PMID:21915222

  14. The Eschenmoser coupling reaction under continuous-flow conditions

    Directory of Open Access Journals (Sweden)

    Sukhdeep Singh

    2011-08-01

    Full Text Available The Eschenmoser coupling is a useful carbon–carbon bond forming reaction which has been used in various different synthesis strategies. The reaction proceeds smoothly if S-alkylated ternary thioamides or thiolactames are used. In the case of S-alkylated secondary thioamides or thiolactames, the Eschenmoser coupling needs prolonged reaction times and elevated temperatures to deliver valuable yields. We have used a flow chemistry system to promote the Eschenmoser coupling under enhanced reaction conditions in order to convert the demanding precursors such as S-alkylated secondary thioamides and thiolactames in an efficient way. Under pressurized reaction conditions at about 220 °C, the desired Eschenmoser coupling products were obtained within 70 s residence time. The reaction kinetics was investigated and 15 examples of different building block combinations are given.

  15. The Commission on Employment Conditions, an ambitious undertaking !

    CERN Multimedia

    Staff Association

    2010-01-01

    Since the beginning of the year, the Commission on Employment Conditions has had much success in the number and ability of its participants. It has mostly worked on salaries, the only compulsory subject of the 2010 five-yearly review. In the framework of this review, the Commission has analysed the results of the comparison carried out by the OECD (see Echo 104 and 105). Through its research and analysis, the Commission has clearly shown that our salaries are lower than those of the comparators. It is there necessary to adjust the salary grid with a salary catch-up and not an increase. In 20 years, no five-yearly review has ended with a significant catch-up. Today it is essential to inform our colleagues that this subject needs to be dealt with and that measures must be taken to finance it, as is the case for restoring the equilibrium of the Pension Fund and Health Insurance schemes. The Commission has established an argumentation to help our fellow delegates talk about the delicate subject of salary catch-...

  16. Influence of reaction conditions and feedstock on hydrochar properties

    International Nuclear Information System (INIS)

    Guo, Shuqing; Dong, Xiangyuan; Wu, Tingting; Zhu, Caixia

    2016-01-01

    Highlights: • Models of hydrochar properties were established based on severity parameter. • Derivative methods were used to study the variation of hydrochar properties. • Water to biomass ratio has a significant effect on the hydrochar yield. • The curves of hydrochar properties can be divided into three stages. • The maximum variation rate of hydrochar properties for six samples is at severity of 5.8–6.4. - Abstract: Hydrothermal carbonization (HTC) is a biomass conversion process to produce a renewable solid fuel (hydrochar). The reaction conditions, such as temperature, time, and water/biomass ratio have key effects on hydrochar characteristics. However, it has not been fully investigated to establish and compare models of hydrochar properties (solid yield, carbon content and HHV) for different biomass HTC at different reaction conditions. These models and the corresponding analytical methods are favorable to optimize operating parameters and process design of HTC. In this work, HTC experiments from corn stalk, longan Shell and NaOH-pretreated longan Shell were carried out at 210 °C, 250 °C and 290 °C for 30 min, 240 min and 480 min with different water to biomass ratios. New models of the hydrochar properties of corn stalk, longan Shell and NaOH-pretreated longan Shell were established based on severity parameter (combined time and temperature) and dose-response function. Also, data of wood, olive stone and grape marc hydrochars (collected from literatures) were used for comparison. The first and second derivative methods were also employed to analyze and compare the variation of these hydrochar properties. The results showed that the hydrchar yield, carbon content, and HHV curves decrease monotonically and can be divided into three significant stages with increasing reaction severity. The water to biomass ratio has a significant effect on the hydrochar yield. With increasing the water to biomass ratio, both the maximum decrease rates and the

  17. 2001: Employment Odyssey or Opportunity for Persons with Handicapping Conditions?

    Science.gov (United States)

    Linari, Ronald F.; Belmont, Robert M.

    1986-01-01

    Implications of trends in population, families, communications, automation, the environment, and employment changes are noted for the training and employment of handicapped persons. The need for emphasis in vocational education on generalizability, job readiness and vocational adjustment skills, and job analysis is stressed. (CL)

  18. Employment and employment conditions in the current economic crisis in Croatia

    Directory of Open Access Journals (Sweden)

    Goran Vukšić

    2014-06-01

    Full Text Available The goal of this research is to analyze developments in employment and employment characteristics during the current crisis in Croatia. The main findings can be summarized as follows: (1 The primary (aggregate mode of adjustment to the crisis was a decline in employment. There are, however, considerable differences in adjustment patterns across economic activities. (2 During the crisis, jobs were lost in the, more dynamic, private sector, while the number of jobs in the public sector (entities in state ownership slightly increased. (3 Economic activities with comparatively larger shares of women in employment have experienced fewer employment cuts and the aggregate employment share of women rose during the crisis, especially in activities with a larger share of public sector workers.(4 There has been a declining share of younger workers during the crisis, justifying policy actions to facilitate their employment. (5 Employees with comparatively lower educational attainment face severe challenges in the labor market, which is a longer term trend, not specific to the crisis period. There are indications that this group of employees enjoys a higher level of protection in the public sector. (6 Analysis also shows a rising significance of more flexible forms of employment: increasing shares of fixed term employees (during the last two observed years, and of part time workers. (7 Working hours do not exhibit any strong trends specific to the crisis, except for the diminishing number of overtime hours per worker.

  19. Empirical Investigation of Job Applicants' Reactions to Taking a Pre-Employment Honesty Test.

    Science.gov (United States)

    Jones, John W.; Joy, Dennis

    Employee theft is widespread and difficult to detect. Many companies have attempted to control the employee theft problem through pre-employment screening. The use of paper-and-pencil honesty tests in this process has become increasingly common. These two studies empirically investigated job applicants' (N=450) reactions to taking a pre-employment…

  20. Influence of Reaction Conditions on Lignin Hydrothermal Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Erdocia, Xabier; Prado, Raquel; Corcuera, M. Ángeles; Labidi, Jalel, E-mail: jalel.labidi@ehu.es [Chemical and Environmental Engineering Department, University of the Basque Country, San Seabastian (Spain)

    2014-04-01

    Organosolv lignin, obtained from olive tree pruning under optimized conditions, was subjected to a hydrothermal depolymerization process catalyzed by sodium hydroxide. The depolymerization of lignin was carried out at 300°C using different reaction times (20, 40, 60, 70, 80, 90, and 100 min) in order to study the influence of this parameter on lignin depolymerization. The resulting products (oil and residual lignin) were measured and analyzed by different techniques (GC/MS, high-performance size-exclusion chromatography, and pyrolysis–GC/MS) in order to determine their nature and composition. Coke was also formed, at a lower quantity, uncompetitive repolymerization reactions during the lignin hydrothermal treatment. The maximum oil yield and concentration of monomeric phenolic compounds was obtained after 80 min of reaction time. The highest reaction time studied (100 min) had the worst results with the lowest oil yield and highest coke production.

  1. Conditions of Employment of Technical/Vocational Teachers.

    Science.gov (United States)

    Abrillo, Harry

    A study examined the job requirements and working conditions of vocational and technical education teachers (VTETs) in India, Indonesia, Malaysia, Singapore, and Thailand. Data were gathered (1) from published materials and interviews with officers and staff of concerned agencies and (2) from a project-developed questionnaire that was administered…

  2. Tem holder for sample transfer under reaction conditions

    DEFF Research Database (Denmark)

    Damsgaard, Christian Danvad; Zandbergen, Henny W.; Wagner, Jakob Birkedal

    Environmental transmission electron microscopy (ETEM) studies are usually performed using conventional sample holders in a dedicated ETEM [1] or in a traditional TEM by use of a dedicated high-pressure cell sample holder [2]. In both cases, the setup defines the conditions regarding gas, pressure......]. Furthermore, dedicated transfer holders have been used to transfer catalyst samples between reactor set-ups and TEM at room temperature in inert atmosphere [5]. To take the full advantage of complementary in situ techniques, transfer under reactions conditions is essential. This study introduces the in situ...... transfer concept by use of a dedicated TEM transfer holder capable of enclosing the sample in a gaseous environment at temperatures up to approx. 900C. By oxidation and reduction experiments of Cu nanoparticles it is shown possible to keep the reaction conditions during transfer outside the microscope...

  3. Palladium(II-catalyzed Heck reaction of aryl halides and arylboronic acids with olefins under mild conditions

    Directory of Open Access Journals (Sweden)

    Tanveer Mahamadali Shaikh

    2013-08-01

    Full Text Available A series of general and selective Pd(II-catalyzed Heck reactions were investigated under mild reaction conditions. The first protocol has been developed employing an imidazole-based secondary phosphine oxide (SPO ligated palladium complex (6 as a precatalyst. The catalytic coupling of aryl halides and olefins led to the formation of the corresponding coupled products in excellent yields. A variety of substrates, both electron-rich and electron-poor olefins, were converted smoothly to the targeted products in high yields. Compared with the existing approaches employing SPO–Pd complexes in a Heck reaction, the current strategy features mild reaction conditions and broad substrate scope. Furthermore, we described the coupling of arylboronic acids with olefins, which were catalyzed by Pd(OAc2 and employed N-bromosuccinimide as an additive under ambient conditions. The resulted biaryls have been obtained in moderate to good yields.

  4. Global precarious employment and health inequalities: working conditions, social class, or precariat?

    OpenAIRE

    Muntaner,Carles

    2016-01-01

    Abstract: Changes in employment conditions since the 1980s have been referred to as precarious employment, and terms like flexible, atypical, temporary, part-time, contract, self-employed, irregular, or non-standard employment have also been used. In this essay I review some of the current critiques to the precarious employment construct and advance some potential solutions for its use in epidemiology and public health.

  5. Reactions of animals and people under conditions of brief weightlessness

    Science.gov (United States)

    Kitayev-Smik, L. A.

    1975-01-01

    It has been shown that under brief weightlessness sensory reactions arise in a number of people, mainly those under these conditions for the first time, in the form of spatial and visual illusions, motor excitation, in which tonic and motor components can be distinguished, and vestibular-vegetative disturbances (nausea, vomiting, etc.). In repeated flights with creation of weightlessness, a decrease in the extent of expression and, then, disappearance of these reactions occurred in a significant majority of those studied. Experiments in weightlessness with the vision cut off and with the absence of vestibular functions in the subjects confirm the hypothesis that spatial conceptions of people in weightlessness depend on predominance of gravireceptor or visual afferent signals under these conditions.

  6. Pathways of the Maillard reaction under physiological conditions.

    Science.gov (United States)

    Henning, Christian; Glomb, Marcus A

    2016-08-01

    Initially investigated as a color formation process in thermally treated foods, nowadays, the relevance of the Maillard reaction in vivo is generally accepted. Many chronic and age-related diseases such as diabetes, uremia, atherosclerosis, cataractogenesis and Alzheimer's disease are associated with Maillard derived advanced glycation endproducts (AGEs) and α-dicarbonyl compounds as their most important precursors in terms of reactivity and abundance. However, the situation in vivo is very challenging, because Maillard chemistry is paralleled by enzymatic reactions which can lead to both, increases and decreases in certain AGEs. In addition, mechanistic findings established under the harsh conditions of food processing might not be valid under physiological conditions. The present review critically discusses the relevant α-dicarbonyl compounds as central intermediates of AGE formation in vivo with a special focus on fragmentation pathways leading to formation of amide-AGEs.

  7. Gas phase reactions of organic iodine in containment conditions

    International Nuclear Information System (INIS)

    Kaerkalae, T.; Holm, J.; Auvinen, A.; Zilliacus, R.; Kajolinna, T.; Tapper, U.; Gaenneskog, H.; Ekberg, C.

    2010-01-01

    In case of a hypothetical severe accident it is very likely that iodine at least partly deposits on painted walls of a reactor containment building. Iodine may react with painted surfaces to form organic iodine species. These organic species are a possible source of volatile iodine, which may increase the fraction of releasable iodine. Therefore, it is important to study the transport of organic iodine in containment conditions. Another question is, in which form are the organic iodides transported as gaseous molecules or as aerosol particles resulting from organic iodides reacting with radiolysis products. To answer this last question methyl iodide was fed into the EXSI facility in an air mixture. In some experiments the flow contained also humidity. The reactions took place in a quartz tube heated either to 50 deg. C, 90 deg. C or 120 deg. C. UV-light was used as a source of radiation to produce ozone from oxygen. A separate generator was also applied to reach higher ozone concentrations. Nucleated aerosol particles were collected on plane filters and gaseous iodine species were trapped in trapping bottles. Aerosol mass flow rate and size distribution as well as speciation of gaseous reaction products were measured with several on-line instruments. Collected aerosol particles were analysed with SEM. It was found that the formation of aerosol particles was very fast when ozone and methyl iodide were present in the facility. Even a very low concentration of ozone produced high number concentration of particles. The measured aerosol mass concentration increased with increasing temperature and ozone concentration. Because the particle diameter was quite small (<180 nm), their settling velocity is low. Therefore, iodine containing aerosols may exist in containment atmosphere for a long period of time. Part of methyl iodide was always transported through the facility regardless of experimental conditions. All ozone was consumed in the reactions when only UV-light was

  8. Interrogating the catalytic mechanism of nanoparticle mediated Stille coupling reactions employing bio-inspired Pd nanocatalysts

    Science.gov (United States)

    Pacardo, Dennis B.; Slocik, Joseph M.; Kirk, Kyle C.; Naik, Rajesh R.; Knecht, Marc R.

    2011-05-01

    To address issues concerning the global environmental and energy state, new catalytic technologies must be developed that translate ambient and efficient conditions to heavily used reactions. To achieve this, the structure/function relationship between model catalysts and individual reactions must be critically discerned to identify structural motifs responsible for the reactivity. This is especially true for nanoparticle-based systems where this level of information remains limited. Here we present evidence indicating that peptide-capped Pd nanoparticles drive Stille C-C coupling reactions via Pd atom leaching. Through a series of reaction studies, the materials are shown to be optimized for reactivity under ambient conditions where increases in temperature or catalyst concentration deactivate reactivity due to the leaching process. A quartz crystal microbalance analysis demonstrates that Pd leaching occurs during the initial oxidative addition step at the nanoparticle surface by aryl halides. Together, this suggests that peptide-based materials may be optimally suited for use as model systems to isolate structural motifs responsible for the generation of catalytically reactive materials under ambient synthetic conditions.

  9. Interrogating the catalytic mechanism of nanoparticle mediated Stille coupling reactions employing bio-inspired Pd nanocatalysts.

    Science.gov (United States)

    Pacardo, Dennis B; Slocik, Joseph M; Kirk, Kyle C; Naik, Rajesh R; Knecht, Marc R

    2011-05-01

    To address issues concerning the global environmental and energy state, new catalytic technologies must be developed that translate ambient and efficient conditions to heavily used reactions. To achieve this, the structure/function relationship between model catalysts and individual reactions must be critically discerned to identify structural motifs responsible for the reactivity. This is especially true for nanoparticle-based systems where this level of information remains limited. Here we present evidence indicating that peptide-capped Pd nanoparticles drive Stille C-C coupling reactions via Pd atom leaching. Through a series of reaction studies, the materials are shown to be optimized for reactivity under ambient conditions where increases in temperature or catalyst concentration deactivate reactivity due to the leaching process. A quartz crystal microbalance analysis demonstrates that Pd leaching occurs during the initial oxidative addition step at the nanoparticle surface by aryl halides. Together, this suggests that peptide-based materials may be optimally suited for use as model systems to isolate structural motifs responsible for the generation of catalytically reactive materials under ambient synthetic conditions. © The Royal Society of Chemistry 2011

  10. Developed Hybrid Model for Propylene Polymerisation at Optimum Reaction Conditions

    Directory of Open Access Journals (Sweden)

    Mohammad Jakir Hossain Khan

    2016-02-01

    Full Text Available A statistical model combined with CFD (computational fluid dynamic method was used to explain the detailed phenomena of the process parameters, and a series of experiments were carried out for propylene polymerisation by varying the feed gas composition, reaction initiation temperature, and system pressure, in a fluidised bed catalytic reactor. The propylene polymerisation rate per pass was considered the response to the analysis. Response surface methodology (RSM, with a full factorial central composite experimental design, was applied to develop the model. In this study, analysis of variance (ANOVA indicated an acceptable value for the coefficient of determination and a suitable estimation of a second-order regression model. For better justification, results were also described through a three-dimensional (3D response surface and a related two-dimensional (2D contour plot. These 3D and 2D response analyses provided significant and easy to understand findings on the effect of all the considered process variables on expected findings. To diagnose the model adequacy, the mathematical relationship between the process variables and the extent of polymer conversion was established through the combination of CFD with statistical tools. All the tests showed that the model is an excellent fit with the experimental validation. The maximum extent of polymer conversion per pass was 5.98% at the set time period and with consistent catalyst and co-catalyst feed rates. The optimum conditions for maximum polymerisation was found at reaction temperature (RT 75 °C, system pressure (SP 25 bar, and 75% monomer concentration (MC. The hydrogen percentage was kept fixed at all times. The coefficient of correlation for reaction temperature, system pressure, and monomer concentration ratio, was found to be 0.932. Thus, the experimental results and model predicted values were a reliable fit at optimum process conditions. Detailed and adaptable CFD results were capable

  11. Global precarious employment and health inequalities: working conditions, social class, or precariat?

    OpenAIRE

    Muntaner, Carles

    2016-01-01

    Abstract: Changes in employment conditions since the 1980s have been referred to as precarious employment, and terms like flexible, atypical, temporary, part-time, contract, self-employed, irregular, or non-standard employment have also been used. In this essay I review some of the current critiques to the precarious employment construct and advance some potential solutions for its use in epidemiology and public health. Resumo: Mudanças nas condições de emprego desde os anos 1980s têm sido...

  12. Iodine/steel reactions under severe accident conditions in LWR's

    International Nuclear Information System (INIS)

    Funke, F.; Greger, G-U.; Hellman, S.; Bleier, A.; Morell, W.

    1994-01-01

    Due to large surface areas, the reaction of volatile, molecular iodine (I 2 ) with steel surfaces in the containment may play an important role in predicting the source term to the environment. Both wall retention of iodine and conversion of volatile into non-volatile iodine compounds at steel surfaces have to be considered. Two types of laboratory experiments were carried out at Siemens/KWU in order to investigate the reaction of I 2 at steel surfaces representative for German power plants. 1) For steel coupons submerged in an I 2 solution at T = 50 deg C, 90 deg C or 140 deg C the reaction rate of the I 2 /I - conversion was determined. No iodine loading was observed on the steel in the aqueous phase tests. I 2 reacts with the steel components (Fe, Cr or Ni) to form metal iodides on the surface which are all immediately dissolved in water under dissociation into the metal and the iodide ions. From these experiments, the I 2 /I - conversion rate constants over the temperature range 50 deg C - 140 deg C as well as the activation energy were determined. The measured data are suitable to be included in severe accident iodine codes such as IMPAIR. 2) Steel tubes were exposed to a steam/I 2 flow under dry air at T=120 deg C and steam-condensing conditions at T= 120 deg C and 160 deg C. In dry air I 2 was retained on the steel surface and a deposition rate constant was measured. Under steam-condensing conditions there is an effective conversion of volatile I 2 to non-volatile I - which is subsequently washed off from the steel surface. The I 2 /I - conversion rate constants suitable for modelling this process were determined. No temperature dependency was found in the range 120 deg C - 160 deg C. (author). 4 refs., 2 tabs., 7 figs

  13. The effect of macroeconomic conditions on the care decisions of the employed.

    Science.gov (United States)

    Hughes, Danny R; Khaliq, Amir A

    2014-02-01

    Medical care utilization has been found to be affected indirectly by changes in economic conditions through associated changes in employment or insurance status. However, if individuals interpret external macroeconomic conditions as employment risk, they may alter decisions to seek care even if they remain both employed and insured. To examine the relationship between macroeconomic fluctuations and the medical care usage of Americans who are both employed and insured. Restricting the Medical Expenditure Panel Survey from 1995 to 2008 to respondents whose employment status and insurance status did not change, we employed a fixed-effect Poisson model to examine the association between state average annual unemployment rates and the utilization of 12 medical services. The average annual state unemployment rate was found to be a significant factor in hospital outpatient visits (P macroeconomic conditions are an important factor in the medical decisions of employed and insured individuals. Thus, policy changes that increase access among the unemployed or uninsured may mitigate this employment risk effect and create incentives that potentially alter the utilization decisions among those currently both employed and insured.

  14. 29 CFR 575.7 - Statutory conditions for employment under the waiver.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Statutory conditions for employment under the waiver. 575.7 Section 575.7 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS WAIVER OF CHILD LABOR PROVISIONS FOR AGRICULTURAL EMPLOYMENT OF 10 AND 11 YEAR OLD MINORS IN HAND...

  15. Employment, Work Conditions, and the Home Environment in Single-Mother Families

    Science.gov (United States)

    Lleras, Christy

    2008-01-01

    This study investigates the impact of employment status and work conditions on the quality of the home environment provided by single mothers of preschool-age children. Multivariate analyses were conducted using data from the National Longitudinal Survey of Youth. The results indicate that employment status is not a significant predictor of the…

  16. Influence of reaction conditions on fast pyrolysis of macroalge

    International Nuclear Information System (INIS)

    Bae, Yoon Ju; Kim, Jung Hwan; Cho, Hye Jung; Ko, Jeong Huy; Heo, Hyeon Su; Park, Hye Jin; Park, Young Kwon

    2010-01-01

    Full text: The importance of renewable energy sources has increased rapidly due to the high international crude oil prices and environmental concerns over fossil fuel use. Recently, there has been a growing interest in aquatic biomass, especially marine macro algae, and a number of studies have been initiated to evaluate its potential for bio-energy. This paper reports a fast pyrolysis of macro algae under different reaction conditions such as pyrolysis temperature, particle size and sample quantity. Various macro algae such as Undaria pinnatifida, Laminaria japonica and Porphyra tenera were fast pyro lysed at temperatures between 300-600 degree Celsius in a batch reactor and the main product of bio-oil was obtained. The optimal reaction temperature for the production of bio-oil was 500 degree Celsius. At this temperature, the maximum bio-oil yields were 40.4 wt % ( by Undaria pinnatifida), 37.6 wt % (by Laminaria japonica) and 47.4 wt % (by Porphyra tenera), respectively. In particular, after pre-treatment with 2.0M HCl solution, the product yield of bio-oil was increased in macro algae, Undaria pinnatifida. The pyroylsis gases were analyzed by using GC-TCD and GC-FID and qualitative analyses of bio-oil were performed using GC-MS. The maximum yield of bio-oil, Undaria pinnatifida, Laminaria japonica and Porphyra tenera, was obtained at 500 degree Celsius (40.4 wt %, 37.6 wt % and 47.4 wt %, respectively). (author)

  17. Dissociation of conditioned taste avoidance from conditioned disgust reactions induced by wheel running in rats.

    Science.gov (United States)

    Grant, Virginia L; McDonald, Sarah V; Sheppard, Robyn C; Caldwell, Catherine L; Heeley, Thomas H; Brown, Adam R; Martin, Gerard M

    2012-06-01

    It is well established that wheel running in rats produces conditioned taste avoidance; that is, rats that run in wheels after consuming a novel-tasting solution later consume less of that solution than rats that do not run. In experiment 1, we found that wheel running also produces conditioned disgust reactions, indicated by gapes elicited by both the taste and context that were experienced before running. Experiment 2 showed that the conditioned disgust reactions were likely not due to running itself but to a by-product of running, the rocking of the wheel that occurs when the running stops. When rocking was reduced, the disgust reactions were also reduced, but consumption of the taste solution was not changed, showing dissociation of conditioned taste avoidance and disgust. These findings indicate that the taste avoidance induced by wheel running itself is more like the taste avoidance produced by rewarding drugs than that produced by nausea-inducing drugs. Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.

  18. Measuring employment precariousness in the European Working Conditions Survey: the social distribution in Europe.

    Science.gov (United States)

    Puig-Barrachina, Vanessa; Vanroelen, Christophe; Vives, Alejandra; Martínez, José Miguel; Muntaner, Carles; Levecque, Katia; Benach, Joan; Louckx, Fred

    2014-01-01

    Precarious employment is becoming an increasingly important social determinant of health inequalities among workers. The way in which contemporary employment arrangements and their health consequences are addressed in empirical research is mostly based on the contract-related or employment instability dimension. A broader conceptual approach including various important characteristics of the degrading of employment conditions and relations is needed. The general objective of this paper is to empirically test a new multidimensional construct for measuring precarious employment in an existing database. Special focus is on the social distribution of precarious employment. A subsample of 21,415 participants in the EU-27 from the Fourth European Working Conditions Survey-2005 was analysed. A cross-sectional study of the social distribution of precarious employment was conducted through the analysis of proportional differences according to gender, social class and credentials for the European Union as a whole and within each country. The 8 dimensions of the employment precariousness construct were represented by 11 indicators. In general, women, workers without supervisory authority, those with fewer credentials, and those living in Eastern and Southern European countries suffer the highest levels of precarious employment. Exceptionally, men, workers with supervisory authority and those with the highest credentials suffer the highest levels of long working hours, schedule unpredictability and uncompensated flexible working times. This article offers the first validation for an innovative multidimensional conceptualisation of employment precariousness applied to the analysis of existing survey data, showing the unequal distribution of precarious employment across the European labour force. This set of indicators can be useful for monitoring precarious employment.

  19. Mechanical properties of thermoelectric n-type magnesium silicide synthesized employing in situ spark plasma reaction sintering

    Science.gov (United States)

    Muthiah, Saravanan; Singh, R. C.; Pathak, B. D.; Dhar, Ajay

    2017-07-01

    Thermoelectric devices employing magnesium silicide (Mg2Si) offer an inexpensive and non-toxic solution for green energy generation compared to other existing conventional thermoelectric materials in the mid-temperature range. However, apart from the thermoelectric performance, their mechanical properties are equally important in order to avoid the catastrophic failure of their modules during actual operation. In the present study, we report the synthesis of Mg2Si co-doped with Bi and Sb employing in situ spark plasma reaction sintering and investigate its broad range of mechanical properties. The mechanical properties of the sintered co-doped Mg2Si suggest a significantly enhanced value of hardness ~5.4  ±  0.2 GPa and an elastic modulus ~142.5  ±  6 GPa with a fracture toughness of ~1.71  ±  0.1 MPa  √m. The thermal shock resistance, which is one of the most vital parameter for designing thermoelectric devices, was found to be ~300 W m-1, which is higher than most of the other existing state-of-the-art mid-temperature thermoelectric materials. The friction and wear characteristics of sintered co-doped Mg2Si have been reported for the first time, in order to realize the sustainability of their thermoelectric modules under actual hostile environmental conditions.

  20. THE EMPLOYMENT – PRODUCTIVITY – SALARY RELATION, A CONDITION FOR ACHIEVING LONG - TERM ECONOMIC GROWTH

    Directory of Open Access Journals (Sweden)

    Mihai CHIRILA

    2005-01-01

    Full Text Available The employment-productivity-salary correlation is essential towards setting up conditions for economic growth andlasting social stability. An influence exists from technological changes, current stage of economic development,peculiarities of labour offer, employers – trade-unions interaction, etc. The analysis covers long-term and short-termcycles. In keeping with specificity of development stages, national economy witnesses an interval of productivitygrowth facilitating maximized employment and a rise in salary too. A lower growth rate indicates difficulties inassimilating new technologies; a higher growth rate generates instability in employing labour. Thus, the exercise ofstrong pressure is shown to exist on economic and technological structures. Likewise, this is what happens whenproductivity goes ahead of the separate analyses of the correlations between employment and productivity, on theone hand, and productivity and salary, on the other.

  1. The photochemical reaction of hydrocarbons under extreme thermobaric conditions

    Science.gov (United States)

    Serovaiskii, Aleksandr; Kolesnikov, Anton; Mukhina, Elena; Kutcherov, Vladimir

    2017-10-01

    The photochemical reaction of hydrocarbons was found to play an important role in the experiments with the synthetic petroleum conducted in Diamond Anvil Cell (DAC). Raman spectroscopy with a green laser (514.5 nm) was used for in situ sample analysis. This photochemical effect was investigated in the pressure range of 0.7-5 GPa, in the temperature interval from the ambient conditions to 450°C. The power of laser used in these experiment series was from 0.05 W to 0.6 W. The chemical transformation was observed when the necessary threshold pressure (~2.8 GPa) was reached. This transformation correlated with the luminescence appearance on the Raman spectra and a black opaque spot in the sample was observed in the place where the laser focus was forwarded. The exposure time and laser power (at least in the 0.1-0.5 W range) did not play a role in the 0.1-0.5 GPa range.

  2. Association of employment and working conditions with physical and mental health symptoms for people with fibromyalgia.

    Science.gov (United States)

    Rakovski, Carter; Zettel-Watson, Laura; Rutledge, Dana

    2012-01-01

    This study examines physical and mental health symptoms among people with fibromyalgia (FM) by employment status and working conditions. Secondary data analysis of the 2007 National Fibromyalgia Association Questionnaire study resulted in employment and symptom information for 1702 people of working age with FM. In this cross-sectional internet study, six factors of symptom clusters (physical, mental health, sleeping, concentration, musculoskeletal, support) were seen in the data. Linear regression models used employment, age, income, gender, and education to predict symptom clusters. Among those employed, working conditions were also associated with symptom severity. In the predominately female sample, 51% were working. Of these, 70% worked over 30 hours/week and half had flexible hours. Employment, higher income, and education were strongly associated with fewer symptoms. Working conditions, including level of physical and mental exertion required on the job as well as coworkers' understanding of FM, were related to symptoms, particularly physical and mental health symptoms. Many participants reported modifying their work environment (66%) or changing occupations (33%) due to FM. Work modifications could allow more people with FM to remain employed and alleviate symptoms. Persons with FM should be counseled to consider what elements of their work may lead to symptom exacerbation.

  3. Introduction to the WHO Commission on Social Determinants of Health Employment Conditions Network (EMCONET) study, with a glossary on employment relations.

    Science.gov (United States)

    Benach, Joan; Muntaner, Carles; Solar, Orielle; Santana, Vilma; Quinlan, Michael

    2010-01-01

    Although the conditions and power relations of employment are known to be crucial health determinants for workers and their families, the nature of these relations and their effects on health have yet to be fully researched. Several types of employment--precarious employment in developed countries; informal sectors, child labor, slavery, and bonded labor in developing countries--expose workers to risky working conditions. Hazardous work and occupation-related diseases kill approximately 1,500 workers, globally, every day. Growing scientific evidence suggests that particular employment conditions, such as job insecurity and precarious employment, create adverse health effects; yet the limited number of studies and the poor quality of their methods prevent our understanding, globally, the complexity of employer-employee power relations, working conditions, levels of social protections, and the reality of employment-related health inequalities. This article introduces a special section on employment-related health inequalities, derived from the EMCONET approach, which focuses on (1) describing major methods and sources of information; (2) presenting theoretical models at the micro and macro levels; (3) presenting a typology of labor markets and welfare states worldwide; (4) describing the main findings in employment policies, including four key points for implementing strategies; and (5) suggesting new research developments, a policy agenda, and recommendations. This introduction includes a glossary of terms in the emerging area of employment conditions and health inequalities.

  4. Employment conditions and maternal postpartum mental health: results from the Longitudinal Study of Australian Children.

    Science.gov (United States)

    Cooklin, Amanda R; Canterford, Louise; Strazdins, Lyndall; Nicholson, Jan M

    2011-06-01

    Maternal postpartum mental health is influenced by a broad range of risk and protective factors including social circumstances. Forty percent of Australian women resume employment in the first year postpartum, yet poor quality employment (without security, control, flexibility or leave) has not been investigated as a potential social determinant of maternal psychological distress. This paper examines whether poor quality jobs are associated with an increased risk of maternal postpartum psychological distress. Data were collected from employed mothers of infants ≤12 months (n = 1,300) participating in the Longitudinal Study of Australian Children. Logistic regression analyses estimated the association between job quality and maternal psychological distress, adjusting for prior depression, social support, quality of partner relationship, adverse life events and sociodemographic characteristics. Only 21% of women reported access to all four optimal job conditions. After adjustment for known risk factors for poor maternal mood, mothers were significantly more likely to report psychological distress (adjusted OR = 1.39, 95% CI 1.09, 1.77) with each reduction in the number of optimal employment conditions. Interventions for maternal postpartum affective disorders are unlikely to be successful if major risk factors are not addressed. These results provide strong evidence that employment conditions are associated with maternal postpartum mood, and warrant consideration in psychosocial risk assessments and interventions.

  5. Work Conditions and the Food Choice Coping Strategies of Employed Parents

    Science.gov (United States)

    Devine, Carol M.; Farrell, Tracy J.; Blake, Christine E.; Jastran, Margaret; Wethington, Elaine; Bisogni, Carole A.

    2009-01-01

    Objective: How work conditions relate to parents' food choice coping strategies. Design: Pilot telephone survey. Setting: City in the northeastern United States (US). Participants: Black, white, and Hispanic employed mothers (25) and fathers (25) randomly recruited from low-/moderate-income zip codes; 78% of those reached and eligible…

  6. Programming of employments physical exercises for the improvement of bodily condition of children of midchildhood.

    Directory of Open Access Journals (Sweden)

    Sljusarchuk V.V.

    2011-12-01

    Full Text Available Approaches are considered on forming and realization of maintenance of physical education of students of initial school. The algorithm of programming of maintenance of lessons of physical culture is developed. The program foresees implementation of requirements of general and methodical principles of physical education, positions of theory of adaptation, requirements of the operating program. It is marked that employments must provide for: differentiated going near students, account of interests and to the wishes, motivation to independent employments by physical exercises, to providing of motor high-density. It is recommended to take into account the features of dynamics of indexes of bodily condition of children of different somatotype.

  7. Reaction-diffusion fronts with inhomogeneous initial conditions

    Energy Technology Data Exchange (ETDEWEB)

    Bena, I [Departement de Physique Theorique, Universite de Geneve, CH-1211 Geneva 4 (Switzerland); Droz, M [Departement de Physique Theorique, Universite de Geneve, CH-1211 Geneva 4 (Switzerland); Martens, K [Departement de Physique Theorique, Universite de Geneve, CH-1211 Geneva 4 (Switzerland); Racz, Z [Institute for Theoretical Physics, Eoetvoes University, 1117 Budapest (Hungary)

    2007-02-14

    Properties of reaction zones resulting from A+B {yields} C type reaction-diffusion processes are investigated by analytical and numerical methods. The reagents A and B are separated initially and, in addition, there is an initial macroscopic inhomogeneity in the distribution of the B species. For simple two-dimensional geometries, exact analytical results are presented for the time evolution of the geometric shape of the front. We also show using cellular automata simulations that the fluctuations can be neglected both in the shape and in the width of the front.

  8. Acetalization of furfural with zeolites under benign reaction conditions

    DEFF Research Database (Denmark)

    Rubio-Caballeroa, Juan Miguel; Shunmugavel, Saravanamurugan; Maireles-Torres, Pedro

    2014-01-01

    Acetalization is a viable method to protect carbonyl functionalities in organic compounds and offers apotential synthetic strategy for synthesizing derived chemicals. In this work, several families of commer-cial zeolites have been employed as solid acid catalysts in the acetalization of furfural...

  9. Study of photosensitization reaction progress in a 96 well plate with photosensitizer rich condition using Talaporfin sodium

    Science.gov (United States)

    Ogawa, Emiyu; Takahashi, Mei; Arai, Tsunenori

    2013-02-01

    To quantitatively investigate photosensitization reaction in vitro against myocardial cells with photosensitizer rich condition in solution using Talaporfin sodium in the well of a 96 well plate, we studied photosensitization reaction progress in this well. We have proposed non-thermal conduction block of myocardium tissue using the photosensitization reaction with laser irradiation shortly after Talaporfin sodium injection. In above situation, the photosensitizer is located outside the myocardial cells in high concentration. To understand interaction of the photosensitization reaction in which the photosensitizer distributes outside cells, the photosensitization reaction progress in the well was studied. Talaporfin sodium (799.69 MW) solution and a 663 nm diode laser were used. The photosensitizer solution concentrations of 12.5-37.5 μM were employed. The photosensitizer fluorescence with 0.29 W/cm2 in irradiance, which was optimized in previous cell death study, was measured during the laser irradiation until 40 J/cm2. The photosensitizer solution absorbance and dissolved oxygen pressure after the laser irradiation were also measured. We found that the photosensitization reaction progress had 2 distinctive phases of different reaction rate: rapid photosensitization reaction consuming dissolved oxygen and gentle photosensitization reaction with oxygen diffusion from the solution-air boundary. The dissolved oxygen pressure and photosensitizer solution absorbance were 30% and 80% of the initial values after the laser irradiation, respectively. Therefore, oxygen was rate-controlling factor of the photosensitization reaction in the well with the photosensitizer rich condition. In the oxygen diffusion phase, the oxygen pressure was maintained around 40 mmHg until the laser irradiation of 40 J/cm2 and it is similar to that of myocardium tissue in vivo. We think that our 96 well plate in vitro system may simulate PDT in myocardial tissue with photosensitization reaction

  10. Association between employment status and self-rated health: Korean working conditions survey.

    Science.gov (United States)

    Kwon, Kimin; Park, Jae Bum; Lee, Kyung-Jong; Cho, Yoon-Sik

    2016-01-01

    This research was conducted with an aim of determining the association between employment status and self-rated health. Using the data from the Third Korean Working Conditions Survey conducted in 2011, We included data from 34,783 respondents, excluding employers, self-employed workers, unpaid family workers, others. Self-rated health was compared according to employment status and a logistic regression analysis was performed. Among the 34,783 workers, the number of permanent and non-permanent workers was 27,564 (79.2 %) and 7,219 (20.8 %). The risk that the self-rated health of non-permanent workers was poor was 1.20 times higher when both socio-demographic factors, work environment and work hazards were corrected. In this study, perceived health was found to be worse in the non-permanent workers than permanent workers. Additional research should investigate whether other factors mediate the relationship between employment status and perceived health.

  11. Enhancing chemical synthesis using catalytic reactions under continuous flow conditions

    OpenAIRE

    Asadi, Mousa

    2017-01-01

    Many advantages have been demonstrated for continuous flow chemistry in comparison with batch chemistry; such as easy automation, high level of reproducibility, improved safety, and process reliability. Indeed, with continuous flow processes constant reaction parameters such as temperature, time, amount of reagents, catalyst, solvents, efficient mixing etc. can easily be assured. The research detailed in this PhD thesis takes advantages of flow chemistry applying it to the Fukuyama ...

  12. Gulf migration study: Employment, wages and working conditions of Kerala emigrants in the United Arab Emirates

    OpenAIRE

    K.C. Zachariah; B.A. Prakash; S. Irudaya Rajan

    2002-01-01

    This is the fourth in a series of Working Papers published by the CDS on Kerala migration. Unlike the other three, this one is financed by the Kerala Government and the data were collected in UAE. The objectives of this Working Paper are to: document changes in the labour demand for different categories of emigrant workers, enumerate the emigration policies, examine employment and working conditions, wage levels and related problems of the Kerala emigrants, understand the education and traini...

  13. [Economic crisis and employment conditions: gender differences and the response of social and employment policies. SESPAS report 2014].

    Science.gov (United States)

    Escribà-Agüir, Vicenta; Fons-Martinez, Jaime

    2014-06-01

    The economic crisis has had an impact across the European Union (EU), but has had a devastating impact on the labor market in Spain, which has become the country within the EU-15 with the worst employment indicators. The situation is worse in younger people, half of whom were unemployed in 2012, with a slightly higher rate in men (54.4%) than in women (51.8%). This high unemployment rate will be even more difficult to redress because of the decrease in public spending on active employment per percentage point of unemployment in 2012 compared with 2007. Furthermore, the decrease in spending on passive employment policies will worsen the health of the unemployed population. Copyright © 2013 SESPAS. Published by Elsevier Espana. All rights reserved.

  14. Differences in working conditions and employment arrangements among migrant and non-migrant workers in Europe.

    Science.gov (United States)

    Ronda Pérez, Elena; Benavides, Fernando G; Levecque, Katia; Love, John G; Felt, Emily; Van Rossem, Ronan

    2012-01-01

    To determine migrant workers' exposure to select occupational risks and compare it with that of non-migrant workers in Europe. Based on the European Working Conditions Survey (EWCS-2005, n=29,654 workers, 31 countries) we examined differential prevalence amongst migrant and non-migrant workers' primary paid jobs in terms of employment arrangements (working >10 hours/day, working >5 days/week, on Sundays, without a contract, changes in the work schedule and not free to decide when to take holidays or days off) and working conditions (exposure to hazards including chemical, physical agents, physical load and psychological conditions). For the purpose of this study, a migrant is defined as a person without nationality of the country of residence (n=926). Adjusted prevalence ratios (aPRs) for age, economic sector and education were calculated. Differences in employment arrangements and working conditions were noted by migration status, gender and occupational status. Among non-manual workers, migrant males are more exposed than non-migrant males to negative psychosocial conditions--working at a very high speed (aPR 1.23; 95% CI 1.07-1.42) and shift work (aPR 1.66; 95% CI 1.27-2.17)--and adverse employment arrangements: working on Sundays (aPR 1.91; 95% CI 1.42-2.55), variable starting/finishing times (aPR 1.17; 95% CI 1.04-1.32) and changes in work schedule (aPR 1.56; 95% CI 1.30-1.88). Compared with non-migrant males, male migrant manual workers are the group with a greater number of disparities in terms of exposure to negative working conditions. Female migrant non-manual workers are more exposed to psychosocial conditions - working at very high speed (aPR 1.26; 95% CI 1.10-1.44) and shift work (aPR 1.61; 95% CI 1.29-2.01) while female manual migrant workers were more likely to report standing or walking (aPR 2.43; 95% CI 1.98-2.97), not having a contract (aPR 2.94; 95% CI 2.07-4.10) and not being free to decide days off and holidays (aPR 1.25; 95% CI 1.07-1.48) than

  15. Occupational class inequalities in health across employment sectors: the contribution of working conditions.

    Science.gov (United States)

    Lahelma, Eero; Laaksonen, Mikko; Aittomäki, Akseli

    2009-01-01

    While health inequalities among employees are well documented, their variation and determinants among employee subpopulations are poorly understood. We examined variations in occupational class inequalities in health within four employment sectors and the contribution of working conditions to these inequalities. Cross-sectional data from the Helsinki Health Study in 2000-2002 were used. Each year, employees of the City of Helsinki, aged 40-60 years, received a mailed questionnaire (n = 8,960, 80% women, overall response rate for 3 years 67%). The outcome was physical health functioning measured by the overall physical component summary of SF-36. The socioeconomic indicator was occupational social class. Employment sectors studied were health care, education, social welfare and administration (n = 6,557). Physical and mental workload, and job demands and job control were explanatory factors. Inequality indices from logistic regression analysis were calculated. Occupational class inequalities in physical health functioning were slightly larger in education (1.47) than in the other sectors (1.43-1.40). Physical workload explained 95% of inequalities in social welfare and 32-36% in the other sectors. Job control also partly explained health inequalities. However, adjusting for mental workload and job demands resulted in larger health inequalities. Inequalities in physical health functioning were found within each employment sector, with minor variation in their magnitude. Physical workload was the main explanation for these inequalities, but its contribution varied between the sectors. In contrast, considering psychosocial working conditions led to wider inequalities. Improving physical working conditions among the lower occupational classes would help reduce health inequalities within different employment sectors.

  16. Presidential Green Chemistry Challenge: 2008 Greener Reaction Conditions Award

    Science.gov (United States)

    Presidential Green Chemistry Challenge 2008 award winner, Nalco Company, developed 3D TRASAR technology to monitor the condition of cooling water continuously and add chemicals only when needed, saving water and energy.

  17. Work conditions and the food choice coping strategies of employed parents.

    Science.gov (United States)

    Devine, Carol M; Farrell, Tracy J; Blake, Christine E; Jastran, Margaret; Wethington, Elaine; Bisogni, Carole A

    2009-01-01

    How work conditions relate to parents' food choice coping strategies. Pilot telephone survey. City in the northeastern United States (US). Black, white, and Hispanic employed mothers (25) and fathers (25) randomly recruited from low-/moderate-income zip codes; 78% of those reached and eligible participated. Sociodemographic characteristics; work conditions (hours, shift, job schedule, security, satisfaction, food access); food choice coping strategies (22 behavioral items for managing food in response to work and family demands (ie, food prepared at/away from home, missing meals, individualizing meals, speeding up, planning). Two-tailed chi-square and Fisher exact tests (P restaurant meals, missed breakfast, and prepared entrees. Job security, satisfaction, and food access were also associated with gender-specific strategies. Structural work conditions among parents such as job hours, schedule, satisfaction, and food access are associated with food choice coping strategies with importance for dietary quality. Findings have implications for worksite interventions but need examination in a larger sample.

  18. Heterocyclization reaction of 4-(2-Methylaziridin-1-yl)-3-ureidobenzotrifluorides under appel's conditions

    International Nuclear Information System (INIS)

    Cho, Hyun In; Lee, Kee Jung

    2003-01-01

    The reaction of 4-(2-Methylaziridin-1-yl)-3-ureidobenzotrifluorides 4 with triphenylphosphine, carbon tetrachloride, and triethylamine (Appel's condition) led to the corresponding carbodiimides 5, which underwent intramolecular cycloaddition reaction with aziridine under the reaction condition to give the benzimidazole-fused heterocycles, 2.3-dihydro-1H-imidazo(1,2-a)benzimidazoles 8 and 12,13-dihydro-5H-benzimidazo(2,3-b)(1,3)benzodizzepines 9

  19. Achieving Chemical Equilibrium: The Role of Imposed Conditions in the Ammonia Formation Reaction

    Science.gov (United States)

    Tellinghuisen, Joel

    2006-01-01

    Under conditions of constant temperature T and pressure P, chemical equilibrium occurs in a closed system (fixed mass) when the Gibbs free energy G of the reaction mixture is minimized. However, when chemical reactions occur under other conditions, other thermodynamic functions are minimized or maximized. For processes at constant T and volume V,…

  20. Hydrogen poisoning of the CO oxidation reaction on Pt and Pd under ultrahigh vacuum conditions

    International Nuclear Information System (INIS)

    Strozier, J.A.

    1977-01-01

    The poisoning by hydrogen of the catalyzed oxidation of CO on Pt and Pd under ultrahigh vacuum conditions was investigated. ac pulsing techniques are used in which the pressure of the reactant CO in the reaction chamber is modulated periodically by means of a fast piezoelectric ultrahigh vacuum valve, and the ac component of the product CO 2 is recorded mass spectroscopically by phase-sensitive techniques. The ac CO 2 production rate is measured as a function of hydrogen pressure (1 - 10 x 10 -9 toor) at constant CO and O 2 pressures (approximately equal to 5 x 10 -8 torr), and constant temperature (approximately equal to 700 K). Exact theoretical calculations of CO 2 production rates were carried out employing several models, i.e., oxygen burn-off by hydrogen, incorporating both the Eley-Rideal and Langmuir-Hinshelwood mechanisms. From a comparison with the experimental results, the probable reaction is of the Langmuir-Hinshelwood type and the relevant rate constant is also determined. These results are compared with other results in the literature on hydrogen oxidation on the surface of Pt

  1. Metastable Structures in Cluster Catalysis from First-Principles: Structural Ensemble in Reaction Conditions and Metastability Triggered Reactivity.

    Science.gov (United States)

    Sun, Geng; Sautet, Philippe

    2018-02-28

    Reactivity studies on catalytic transition metal clusters are usually performed on a single global minimum structure. With the example of a Pt 13 cluster under a pressure of hydrogen, we show from first-principle calculations that low energy metastable structures of the cluster can play a major role for catalytic reactivity and that hence consideration of the global minimum structure alone can severely underestimate the activity. The catalyst is fluxional with an ensemble of metastable structures energetically accessible at reaction conditions. A modified genetic algorithm is proposed to comprehensively search for the low energy metastable ensemble (LEME) structures instead of merely the global minimum structure. In order to reduce the computational cost of density functional calculations, a high dimensional neural network potential is employed to accelerate the exploration. The presence and influence of LEME structures during catalysis is discussed by the example of H covered Pt 13 clusters for two reactions of major importance: hydrogen evolution reaction and methane activation. The results demonstrate that although the number of accessible metastable structures is reduced under reaction condition for Pt 13 clusters, these metastable structures can exhibit high activity and dominate the observed activity due to their unique electronic or structural properties. This underlines the necessity of thoroughly exploring the LEME structures in catalysis simulations. The approach enables one to systematically address the impact of isomers in catalysis studies, taking into account the high adsorbate coverage induced by reaction conditions.

  2. Chemical and physical reactions under thermal plasmas conditions

    International Nuclear Information System (INIS)

    Fauchais, P.; Vardelle, A.; Vardelle, M.; Coudert, J.F.

    1987-01-01

    Basic understanding of the involved phenomena lags far behind industrial development that requires now a better knowledge of the phenomena to achieve a better control of the process allowing to improve the quality of the products. Thus the authors try to precise what is their actual knowledge in the fields of: plasma generators design; plasma flow models with the following key points: laminar or turbulent flow, heat transfer to walls, 2D or 3D models, non equilibrium effects, mixing problems when chemical reactions are to be taken into account with very fast kinetics, electrode regions, data for transport properties and kinetic rates; nucleation problems; plasma flow characteristics measurements: temperature or temperatures and population of excited states (automatized emission spectroscopy, LIF, CARS) as well as flow velocity (LDA with small particles, Doppler effects...); plasma and particles momentum and heat transfer either with models taking into account particles size and injection velocity distributions, heat propagation, vaporization, Kundsen effect, turbulences ... or with measurements: particles velocity and flux distributions (Laser Anemometry) as well as surface temperature distributions (two colour pyrometry in flight statistical or not)

  3. Medication therapy management and condition care services in a community-based employer setting.

    Science.gov (United States)

    Johannigman, Mark J; Leifheit, Michael; Bellman, Nick; Pierce, Tracey; Marriott, Angela; Bishop, Cheryl

    2010-08-15

    A program in which health-system pharmacists and pharmacy technicians provide medication therapy management (MTM), wellness, and condition care (disease management) services under contract with local businesses is described. The health-system pharmacy department's Center for Medication Management contracts directly with company benefits departments for defined services to participating employees. The services include an initial wellness and MTM session and, for certain patients identified during the initial session, ongoing condition care. The initial appointment includes a medication history, point-of-care testing for serum lipids and glucose, body composition analysis, and completion of a health risk assessment. The pharmacist conducts a structured MTM session, reviews the patient's test results and risk factors, provides health education, discusses opportunities for cost savings, and documents all activities on the patient's medication action plan. Eligibility for the condition care program is based on a diagnosis of diabetes, hypertension, asthma, heart failure, or hyperlipidemia or elevation of lipid or glucose levels. Findings are summarized for employers after the initial wellness screening and at six-month intervals. Patients receiving condition care sign a customized contract, establish goals, attend up to four MTM sessions per year, and track their information on a website; employers may offer incentives for participation. When pharmacists recommend adjustments to therapy or cost-saving changes, it is up to patients to discuss these with their physician. A survey completed by each patient after the initial wellness session has indicated high satisfaction. Direct cost savings related to medication changes have averaged $253 per patient per year. Total cost savings to companies in the first year of the program averaged $1011 per patient. For the health system, the program has been financially sustainable. Key laboratory values indicate positive clinical

  4. Conditions for extinction events in chemical reaction networks with discrete state spaces.

    Science.gov (United States)

    Johnston, Matthew D; Anderson, David F; Craciun, Gheorghe; Brijder, Robert

    2018-05-01

    We study chemical reaction networks with discrete state spaces and present sufficient conditions on the structure of the network that guarantee the system exhibits an extinction event. The conditions we derive involve creating a modified chemical reaction network called a domination-expanded reaction network and then checking properties of this network. Unlike previous results, our analysis allows algorithmic implementation via systems of equalities and inequalities and suggests sequences of reactions which may lead to extinction events. We apply the results to several networks including an EnvZ-OmpR signaling pathway in Escherichia coli.

  5. Optimal condition for employing an axicon-generated Bessel beam to fabricate cylindrical microlens arrays

    Science.gov (United States)

    Luo, Zhi; Yin, Kai; Dong, Xinran; Duan, Ji’an

    2018-05-01

    A numerical algorithm, modelling the transformation from a Gaussian beam to a Bessel beam, is presented for the purpose to study the optimal condition for employing an axicon-generated Bessel beam to fabricate cylindrical microlens arrays (CMLAs). By applying the numerical algorithm to simulate the spatial intensity distribution behind the axicon under different defects of a rotund-apex and different diameter ratios of an incident beam to the axicon, we find that the diffraction effects formed by the axicon edge can be almost eliminated when the diameter ratio is less than 1:2, but the spatial intensity distribution is disturbed dramatically even a few tens of microns deviation of the apex, especially for the front part of the axicon-generated Bessel beam. Fortunately, the lateral intensity profile in the rear part still maintains a desirable Bessel curve. Therefore, the rear part of the Bessel area and the less than 1:2 diameter ratio are the optimal choice for employing an axicon-generated Bessel beam to implement surface microstructures fabrication. Furthermore, by applying the optimal conditions to direct writing microstructures on fused silica with a femtosecond (fs) laser, a large area close-packed CMLA is fabricated. The CMLA presents high quality and uniformity and its optical performance is also demonstrated.

  6. Surface chemistry of tribochemical reactions explored in ultrahigh vacuum conditions

    International Nuclear Information System (INIS)

    Lara-Romero, Javier; Maya-Yescas, Rafael; Rico-Cerda, Jose Luis; Rivera-Rojas, Jose Luis; Castillo, Fernando Chinas; Kaltchev, Matey; Tysoe, Wilfred T.

    2006-01-01

    The thermal decomposition of model extreme-pressure lubricant additives on clean iron was studied in ultrahigh vacuum conditions using molecular beam strategies. Methylene chloride and chloroform react to deposit a solid film consisting of FeCl 2 and carbon, and evolve only hydrogen into the gas phase. No gas-phase products and less carbon on the surface are detected in the case of carbon tetrachloride. Dimethyl and diethyl disulfide react on clean iron to deposit a saturated sulfur plus carbon layer at low temperatures (∼600 K) and an iron sulfide film onto a Fe + C underlayer at higher temperatures (∼950 K). Methane is the only gas-phase product when dimethyl disulfide reacts with iron. Ethylene and hydrogen are detected when diethyl disulfide is used

  7. Conditional symmetries for systems of PDEs: new definitions and their application for reaction-diffusion systems

    International Nuclear Information System (INIS)

    Cherniha, Roman

    2010-01-01

    New definitions of Q-conditional symmetry for systems of PDEs are presented, which generalize the standard notation of non-classical (conditional) symmetry. It is shown that different types of Q-conditional symmetry of a system generate a hierarchy of conditional symmetry operators. A class of two-component nonlinear reaction-diffusion systems is examined to demonstrate the applicability of the definitions proposed and it is shown when different definitions of Q-conditional symmetry lead to the same operators.

  8. Information Management in Portugal: education and employment conditions and some prospects

    Directory of Open Access Journals (Sweden)

    Maria Cristina Vieira de Freitas

    2014-09-01

    Full Text Available The Professors Cristina Freitas and Maria da Graça Simões answer questions prepared by teachers from the Faculdade de Informação e Comunicação (Gestão da Informação Undergraduate Degree da Universidade Federal de Goiás - UFG. The questions are related to the educational structure dedicated to the issues of information management in Portugal, the influence of the "Big Data" phenomenon on education and training in the area - including discussions on data governance, the fundation areas of Information Management and the main approaches to information research in the Country. Besides, they discuss the employment conditions (threats and opportunities for professionals in Information Management in Portugal and in Europe [Available Language: Portuguese/Portugal].

  9. Representation of boundary conditions in thermal reactor global analysis by diffusion theory employing finite difference approximation

    International Nuclear Information System (INIS)

    Paul, O.P.K.

    1978-01-01

    An approach to simulate the flux vanishing boundary condition in solving the two group coupled neutron diffusion equations in three dimensions (x, y, z) employed to calculate the flux distribution and keff of the reactor is summarised. This is of particular interest when the flux vanishing boundary in x, y, z directions is not an integral multiple of the mesh spacings in these directions. The method assumes the flux to be negative, hypothetically at the mesh points lying outside the boundary and thus the finite difference formalism for Laplacian operator, taking into account six neighbours of a mesh point in a square mesh arrangement, is expressed in a general form so as to account for the boundary mesh points of the system. This approach has been incorporated in a three dimensional diffusion code similar to TAPPS23 and has been used for IRT-2000 reactor and the results are quite satisfactory. (author)

  10. Biofilm reactors for industrial bioconversion processes: employing potential of enhanced reaction rates

    Directory of Open Access Journals (Sweden)

    Karcher Patrick

    2005-08-01

    Full Text Available Abstract This article describes the use of biofilm reactors for the production of various chemicals by fermentation and wastewater treatment. Biofilm formation is a natural process where microbial cells attach to the support (adsorbent or form flocs/aggregates (also called granules without use of chemicals and form thick layers of cells known as "biofilms." As a result of biofilm formation, cell densities in the reactor increase and cell concentrations as high as 74 gL-1 can be achieved. The reactor configurations can be as simple as a batch reactor, continuous stirred tank reactor (CSTR, packed bed reactor (PBR, fluidized bed reactor (FBR, airlift reactor (ALR, upflow anaerobic sludge blanket (UASB reactor, or any other suitable configuration. In UASB granular biofilm particles are used. This article demonstrates that reactor productivities in these reactors have been superior to any other reactor types. This article describes production of ethanol, butanol, lactic acid, acetic acid/vinegar, succinic acid, and fumaric acid in addition to wastewater treatment in the biofilm reactors. As the title suggests, biofilm reactors have high potential to be employed in biotechnology/bioconversion industry for viable economic reasons. In this article, various reactor types have been compared for the above bioconversion processes.

  11. Biofilm reactors for industrial bioconversion processes: employing potential of enhanced reaction rates

    Science.gov (United States)

    Qureshi, Nasib; Annous, Bassam A; Ezeji, Thaddeus C; Karcher, Patrick; Maddox, Ian S

    2005-01-01

    This article describes the use of biofilm reactors for the production of various chemicals by fermentation and wastewater treatment. Biofilm formation is a natural process where microbial cells attach to the support (adsorbent) or form flocs/aggregates (also called granules) without use of chemicals and form thick layers of cells known as "biofilms." As a result of biofilm formation, cell densities in the reactor increase and cell concentrations as high as 74 gL-1 can be achieved. The reactor configurations can be as simple as a batch reactor, continuous stirred tank reactor (CSTR), packed bed reactor (PBR), fluidized bed reactor (FBR), airlift reactor (ALR), upflow anaerobic sludge blanket (UASB) reactor, or any other suitable configuration. In UASB granular biofilm particles are used. This article demonstrates that reactor productivities in these reactors have been superior to any other reactor types. This article describes production of ethanol, butanol, lactic acid, acetic acid/vinegar, succinic acid, and fumaric acid in addition to wastewater treatment in the biofilm reactors. As the title suggests, biofilm reactors have high potential to be employed in biotechnology/bioconversion industry for viable economic reasons. In this article, various reactor types have been compared for the above bioconversion processes. PMID:16122390

  12. Biofilm reactors for industrial bioconversion processes: employing potential of enhanced reaction rates.

    Science.gov (United States)

    Qureshi, Nasib; Annous, Bassam A; Ezeji, Thaddeus C; Karcher, Patrick; Maddox, Ian S

    2005-08-25

    This article describes the use of biofilm reactors for the production of various chemicals by fermentation and wastewater treatment. Biofilm formation is a natural process where microbial cells attach to the support (adsorbent) or form flocs/aggregates (also called granules) without use of chemicals and form thick layers of cells known as "biofilms." As a result of biofilm formation, cell densities in the reactor increase and cell concentrations as high as 74 gL(-1) can be achieved. The reactor configurations can be as simple as a batch reactor, continuous stirred tank reactor (CSTR), packed bed reactor (PBR), fluidized bed reactor (FBR), airlift reactor (ALR), upflow anaerobic sludge blanket (UASB) reactor, or any other suitable configuration. In UASB granular biofilm particles are used. This article demonstrates that reactor productivities in these reactors have been superior to any other reactor types. This article describes production of ethanol, butanol, lactic acid, acetic acid/vinegar, succinic acid, and fumaric acid in addition to wastewater treatment in the biofilm reactors. As the title suggests, biofilm reactors have high potential to be employed in biotechnology/bioconversion industry for viable economic reasons. In this article, various reactor types have been compared for the above bioconversion processes.

  13. Synchronization of Reaction-Diffusion Neural Networks With Dirichlet Boundary Conditions and Infinite Delays.

    Science.gov (United States)

    Sheng, Yin; Zhang, Hao; Zeng, Zhigang

    2017-10-01

    This paper is concerned with synchronization for a class of reaction-diffusion neural networks with Dirichlet boundary conditions and infinite discrete time-varying delays. By utilizing theories of partial differential equations, Green's formula, inequality techniques, and the concept of comparison, algebraic criteria are presented to guarantee master-slave synchronization of the underlying reaction-diffusion neural networks via a designed controller. Additionally, sufficient conditions on exponential synchronization of reaction-diffusion neural networks with finite time-varying delays are established. The proposed criteria herein enhance and generalize some published ones. Three numerical examples are presented to substantiate the validity and merits of the obtained theoretical results.

  14. influence of severe conditions on the concrete employed in nuclear technology

    International Nuclear Information System (INIS)

    Khalil, W.M.K.S.

    2006-01-01

    this thesis is mainly concentrating on honing the efficiency of heavy-weight high -performance (HWHP) concrete, developed from local aggregates together with additives that are waste products of other manufacturing processes, for the purpose of producing radiation shields, to attenuate gamma-rays in peaceful active-service facilitations . in other words, the thesis is in attempt to develop a special type of heavy concrete of various advantages that would enhance its performance in severe environment. such advantages may embrace concurrent improvements; such as high specific gravity, workability, high compressive strength, efficient attenuator for gamma radiation, and resistant to elevated temperature along with chemical attack.the named HWHP concrete was mainly prepared using two types of heavy aggregates, ilmenite (iron ore) and barite . in addition usual concrete (dolomite/sand) was also employed in this thesis to compare the obtained HWHP concrete. the practical facet of this thesis accounts for evaluating the influence of severe conditions, concomitantly and consecutively, on mechanical , morphological and attenuation characteristics for the three types of concrete

  15. The Impact of Employment and Self-Rated Economic Condition on the Subjective Well-Being of Older Korean Immigrants.

    Science.gov (United States)

    Kim, Bum Jung; Lee, Yura; Sangalang, Cindy; Harris, Lesley M

    2015-09-01

    Extensive research has demonstrated a relationship between socioeconomic factors and health among older adults, yet fewer studies have explored this relationship with older immigrants. This study aims to examine the influence of employment and self-rated economic condition on the subjective well-being of older Korean immigrants in the United States. Data were drawn from a cross-sectional study of 205 older Korean immigrants, aged 65 to 90, in Los Angeles County. Hierarchical regression was employed to explore the independent and interactive effects of employment status and self-rated economic condition. The study found that employment and self-rated economic status were positively associated with subjective well-being. Also, the interaction between employment and self-rated economic status was significantly associated with higher levels of subjective well-being, such that the influence of self-rated economic condition was stronger for unemployed older Korean immigrants compared with those who were employed. This population-based study provides empirical evidence that employment and self-rated economic condition are directly associated with subjective well-being for older Korean immigrants. © The Author(s) 2015.

  16. Bifurcation of positive solutions to scalar reaction-diffusion equations with nonlinear boundary condition

    Science.gov (United States)

    Liu, Ping; Shi, Junping

    2018-01-01

    The bifurcation of non-trivial steady state solutions of a scalar reaction-diffusion equation with nonlinear boundary conditions is considered using several new abstract bifurcation theorems. The existence and stability of positive steady state solutions are proved using a unified approach. The general results are applied to a Laplace equation with nonlinear boundary condition and bistable nonlinearity, and an elliptic equation with superlinear nonlinearity and sublinear boundary conditions.

  17. Recent progress in transition-metal-catalyzed reduction of molecular dinitrogen under ambient reaction conditions.

    Science.gov (United States)

    Nishibayashi, Yoshiaki

    2015-10-05

    This paper describes our recent progress in catalytic nitrogen fixation by using transition-metal-dinitrogen complexes as catalysts. Two reaction systems for the catalytic transformation of molecular dinitrogen into ammonia and its equivalent such as silylamine under ambient reaction conditions have been achieved by the molybdenum-, iron-, and cobalt-dinitrogen complexes as catalysts. Many new findings presented here may provide new access to the development of economical nitrogen fixation in place of the Haber-Bosch process.

  18. Characterization of reaction conditions providing rapid and specific cysteine alkylation for peptide-based mass spectrometry.

    Science.gov (United States)

    Paulech, Jana; Solis, Nestor; Cordwell, Stuart J

    2013-01-01

    Alkylation converts Cys thiols to thioethers and prevents unwanted side reactions, thus facilitating mass spectrometric identification of Cys-containing peptides. Alkylation occurs preferentially at Cys due to its high nucleophilicity, however reactions at other such sites are possible. N-ethylmaleimide (NEM) shows rapid reaction kinetics with Cys and careful definition of reaction conditions results in little reactivity at other sites. Analysis of a protein standard alkylated under differing reaction conditions (pH, NEM concentrations and reaction times) was performed using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) and selected reaction monitoring (SRM) of NEM-modified and unmodified peptide pairs. Mis-alkylation sites at primary and secondary amines were identified and limited to one equivalent of NEM. No evidence for hydroxyl or thioether alkylation was observed. Improved specificity was achieved by restricting the pH below neutral, NEM concentration below 10mM and/or reaction time to below 5min. Maximal removal of Cys activity was observed in tissue homogenates at 40mM NEM within 1min, dependent upon efficient protein denaturation. SRM assays identified peptide-specific levels of mis-alkylation, indicating that NEM-modified to unmodified ratios did not exceed 10%, with the exception of Cys alkylation that proceeded to 100%, and some Lys residues that resulted in tryptic missed cleavages. High reactivity was observed for His residues considering their relatively low abundance. These data indicate that rapid and specific Cys alkylation is possible with NEM under relatively mild conditions, with more abrasive conditions leading to increased non-specific alkylation without appreciable benefit for MS-based proteomics. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Tribological reactions of perfluoroalkyl polyether oils with stainless steel under ultrahigh vacuum conditions at room temperature

    Science.gov (United States)

    Mori, Shigeyuki; Morales, Wilfredo

    1989-01-01

    The reaction between three types of commercial perfluoroalkyl polyether (PFPE) oils and stainless steel 440C was investigated experimentally during sliding under ultrahigh vacuum conditions at room temperature. It is found that the tribological reaction of PFPE is mainly affected by the activity of the mechanically formed fresh surfaces of metals rather than the heat generated at the sliding contacts. The fluorides formed on the wear track act as a boundary layer, reducing the friction coefficient.

  20. Critical ignition conditions in exothermically reacting systems: first-order reactions.

    Science.gov (United States)

    Filimonov, Valeriy Yu

    2017-10-01

    In this paper, the comparative analysis of the thermal explosion (TE) critical conditions on the planes temperature-conversion degree and temperature-time was conducted. It was established that the ignition criteria are almost identical only at relatively small values of Todes parameter. Otherwise, the results of critical conditions analysis on the plane temperature-conversion degree may be wrong. The asymptotic method of critical conditions calculation for the first-order reactions was proposed (taking into account the reactant consumption). The degeneration conditions of TE were determined. The calculation of critical conditions for specific first-order reaction was made. The comparison of the analytical results obtained with the results of numerical calculations and experimental data showed that they are in good agreement.

  1. Critical ignition conditions in exothermically reacting systems: first-order reactions

    Science.gov (United States)

    Filimonov, Valeriy Yu.

    2017-10-01

    In this paper, the comparative analysis of the thermal explosion (TE) critical conditions on the planes temperature-conversion degree and temperature-time was conducted. It was established that the ignition criteria are almost identical only at relatively small values of Todes parameter. Otherwise, the results of critical conditions analysis on the plane temperature-conversion degree may be wrong. The asymptotic method of critical conditions calculation for the first-order reactions was proposed (taking into account the reactant consumption). The degeneration conditions of TE were determined. The calculation of critical conditions for specific first-order reaction was made. The comparison of the analytical results obtained with the results of numerical calculations and experimental data showed that they are in good agreement.

  2. Poor Employment Conditions Adversely Affect Mental Health Outcomes Among Surgical Trainees.

    Science.gov (United States)

    Kevric, Jasmina; Papa, Nathan; Perera, Marlon; Rashid, Prem; Toshniwal, Sumeet

    Poor mental health in junior clinicians is prevalent and may lead to poor productivity and significant medical errors. We aimed to provide contemporary data on the mental health of surgical trainees and identify risk factors relating to poorer mental health outcomes. A detailed questionnaire was developed comprising questions based on the 36-item short-form health survey (SF-36) and Physical Activity Questionnaire. Each of the questionnaires has proven validity and reliability in the clinical context. Ethics approval was obtained from the Royal Australasian College of Surgeons. The questionnaire was aimed at surgical registrars. We used Physical Activity Questionnaire, SF-36 scores and linear regression to evaluate the effect of putative predictors on mental health. A total of 83 responses were collected during the study period, of which 49 (59%) were from men and 34 (41%) were from women. The mean Mental Component Summary (MCS) score for both sexes was significantly lower than the population mean at ages 25-34 (p work culture and a feeling of a lack of support at work were extremely strong predictors of a lower MCS score (p Hours of overtime worked, particularly unpaid overtime, were also strong predictors of a poorer score. Australian surgical trainees reported lower MCS scores from the SF-36 questionnaire compared to the general population. Increasing working hours, unpaid overtime, poor job security, and job satisfaction were associated with poorer scores among trainees. Interventions providing improved working conditions need to be considered by professional training bodies and employers. Copyright © 2018 Association of Program Directors in Surgery. All rights reserved.

  3. Nonlinear reaction-diffusion systems conditional symmetry, exact solutions and their applications in biology

    CERN Document Server

    Cherniha, Roman

    2017-01-01

    This book presents several fundamental results in solving nonlinear reaction-diffusion equations and systems using symmetry-based methods. Reaction-diffusion systems are fundamental modeling tools for mathematical biology with applications to ecology, population dynamics, pattern formation, morphogenesis, enzymatic reactions and chemotaxis. The book discusses the properties of nonlinear reaction-diffusion systems, which are relevant for biological applications, from the symmetry point of view, providing rigorous definitions and constructive algorithms to search for conditional symmetry (a nontrivial generalization of the well-known Lie symmetry) of nonlinear reaction-diffusion systems. In order to present applications to population dynamics, it focuses mainly on two- and three-component diffusive Lotka-Volterra systems. While it is primarily a valuable guide for researchers working with reaction-diffusion systems  and those developing the theoretical aspects of conditional symmetry conception,...

  4. Highly Regio- and Stereoselective Diels-Alder Cycloadditions via Two-Step and Multicomponent Reactions Promoted by Infrared Irradiation under Solvent-Free Conditions

    Science.gov (United States)

    Flores-Conde, Maria Ines; Reyes, Leonor; Herrera, Rafael; Rios, Hulme; Vazquez, Miguel A.; Miranda, Rene; Tamariz, Joaquin; Delgado, Francisco

    2012-01-01

    Infrared irradiation promoted the Diels-Alder cycloadditions of exo-2-oxazolidinone dienes 1–3 with the Knoevenagel adducts 4–6, as dienophiles, leading to the synthesis of new 3,5-diphenyltetrahydrobenzo[d]oxazol-2-one derivatives (7, 9, 11 and 13–17), under solvent-free conditions. These cycloadditions were performed with good regio- and stereoselectivity, favoring the para-endo cycloadducts. We also evaluated the one-pot three-component reaction of active methylene compounds 20, benzaldehydes 21 and exo-2-oxazolidinone diene 2 under the same reaction conditions. A cascade Knoevenagel condensation/Diels-Alder cycloaddition reaction was observed, resulting in the final adducts 13–16 in similar yields. These procedures are environmentally benign, because no solvent and no catalyst were employed in these processes. The regioselectivity of these reactions was rationalized by Frontier Molecular Orbital (FMO) calculations. PMID:22489113

  5. Highly Regio- and Stereoselective Diels-Alder Cycloadditions via Two-Step and Multicomponent Reactions Promoted by Infrared Irradiation under Solvent-Free Conditions

    Directory of Open Access Journals (Sweden)

    Francisco Delgado

    2012-02-01

    Full Text Available Infrared irradiation promoted the Diels-Alder cycloadditions of exo-2-oxazolidinone dienes 1–3 with the Knoevenagel adducts 4–6, as dienophiles, leading to the synthesis of new 3,5-diphenyltetrahydrobenzo[d]oxazol-2-one derivatives (7, 9, 11 and 13–17, under solvent-free conditions. These cycloadditions were performed with good regio- and stereoselectivity, favoring the para-endo cycloadducts. We also evaluated the one-pot three-component reaction of active methylene compounds 20, benzaldehydes 21 and exo-2-oxazolidinone diene 2 under the same reaction conditions. A cascade Knoevenagel condensation/Diels-Alder cycloaddition reaction was observed, resulting in the final adducts 13–16 in similar yields. These procedures are environmentally benign, because no solvent and no catalyst were employed in these processes. The regioselectivity of these reactions was rationalized by Frontier Molecular Orbital (FMO calculations.

  6. Reaction progress pathways for glass and spent fuel under unsaturated conditions

    International Nuclear Information System (INIS)

    Bates, J.; Finn, P.; Bourcier, W.; Stout, R.

    1994-10-01

    The source term for the release of radionuclides from a nuclear waste repository is the waste form. In order to assess the performance of the repository and the engineered barrier system (EBS) compared to regulations established by the Nuclear Regulatory Commission and the Environmental Protection Agency it is necessary (1) to use available data to place bounding limits on release rates from the EBS, and (2) to develop a mechanistic predictive model of the radionuclide release and validate the model against tests done under a variety of different potential reaction conditions. The problem with (1) is that there is little experience to use when evaluating waste form reaction under unsaturated conditions such that errors in applying expert judgment to the problem may be significant. The second approach, to test and model the waste form reaction, is a more defensible means of providing input to the prediction of radionuclide release. In this approach, information related to the source term has a technical basis and provides a starting point to make reasonable assumptions for long-term behavior. Key aspects of this approach are an understanding of the reaction progress mechanism and the ability to model the tests using a geochemical code such as EQ3/6. Current knowledge of glass, UO 2 , and spent fuel reactions under different conditions are described below

  7. Study of the optimal reaction conditions for assay of the mouse alternative complement pathway

    NARCIS (Netherlands)

    Dijk, H. van; Rademaker, P.M.; Klerx, J.P.A.M.; Willers, J.M.M.

    1985-01-01

    The optimal reaction conditions for hemolytic assay of alternative complement pathway activity in mouse serum were investigated. A microtiter system was used, in which a number of 7.5×106 rabbit erythrocytes per test well appeared to be optimal. Rabbit erythrocytes were superior as target cells over

  8. Some conditions affecting the definition of design basis accidents relating to sodium/water reactions

    International Nuclear Information System (INIS)

    Bolt, P.R.

    1984-01-01

    The possible damaging effects of large sodium/water reactions on the steam generator, IHX and secondary circuit are considered. The conditions to be considered in defining the design basis accidents for these components are discussed, together with some of the assumptions that may be associated with design assessments of the scale of the accidents. (author)

  9. Employment Condition, Economic Deprivation and Self-Evaluated Health in Europe: Evidence from EU-SILC 2009–2012

    Science.gov (United States)

    Bacci, Silvia; Pigini, Claudia; Seracini, Marco; Minelli, Liliana

    2017-01-01

    Background: The mixed empirical evidence about employment conditions (i.e., permanent vs. temporary job, full-time vs. part-time job) as well as unemployment has motivated the development of conceptual models with the aim of assessing the pathways leading to effects of employment status on health. Alongside physically and psychologically riskier working conditions, one channel stems in the possibly severe economic deprivation faced by temporary workers. We investigate whether economic deprivation is able to partly capture the effect of employment status on Self-evaluated Health Status (SHS). Methods: Our analysis is based on the European Union Statistics on Income and Living Conditions (EU-SILC) survey, for a balanced sample from 26 countries from 2009 to 2012. We estimate a correlated random-effects logit model for the SHS that accounts for the ordered nature of the dependent variable and the longitudinal structure of the data. Results and Discussion: Material deprivation and economic strain are able to partly account for the negative effects on SHS from precarious and part-time employment as well as from unemployment that, however, exhibits a significant independent negative association with SHS. Conclusions: Some of the indicators used to proxy economic deprivation are significant predictors of SHS and their correlation with the employment condition is such that it should not be neglected in empirical analysis, when available and further to the monetary income. PMID:28165375

  10. Employment Condition, Economic Deprivation and Self-Evaluated Health in Europe: Evidence from EU-SILC 2009-2012.

    Science.gov (United States)

    Bacci, Silvia; Pigini, Claudia; Seracini, Marco; Minelli, Liliana

    2017-02-03

    Background : The mixed empirical evidence about employment conditions (i.e., permanent vs. temporary job, full-time vs. part-time job) as well as unemployment has motivated the development of conceptual models with the aim of assessing the pathways leading to effects of employment status on health. Alongside physically and psychologically riskier working conditions, one channel stems in the possibly severe economic deprivation faced by temporary workers. We investigate whether economic deprivation is able to partly capture the effect of employment status on Self-evaluated Health Status (SHS). Methods : Our analysis is based on the European Union Statistics on Income and Living Conditions (EU-SILC) survey, for a balanced sample from 26 countries from 2009 to 2012. We estimate a correlated random-effects logit model for the SHS that accounts for the ordered nature of the dependent variable and the longitudinal structure of the data. Results and Discussion : Material deprivation and economic strain are able to partly account for the negative effects on SHS from precarious and part-time employment as well as from unemployment that, however, exhibits a significant independent negative association with SHS. Conclusions : Some of the indicators used to proxy economic deprivation are significant predictors of SHS and their correlation with the employment condition is such that it should not be neglected in empirical analysis, when available and further to the monetary income.

  11. Considerations on the conditions under which the employer may monitor their employees at the workplace

    Directory of Open Access Journals (Sweden)

    Monica Gheorghe

    2017-12-01

    Full Text Available Recently, the European Court of Human Rights in the case Bărbulescu v. România has ruled that the national courts did not ensure respect for the right to privacy in the employment relationship of an employee who had been disciplinary dismissed for using the internet and an IT application in the personal interest during the working hours, dismissal which was based on evidence obtained after the employer had monitored the employee’s electronic communications. The Court concluded that the national courts failed to strike a fair balance between the employee’s right to private life at the workplace and the employer’s right to supervise and control the work of his employees. Thus, the Court found a violation of Article 8 of the European Convention of Human Rights. In its decision, the Court specified the criteria to be applied by the national authorities in order to achieve a balance between the rights of the two parties (employee-employers. The herein study aims to briefly analyze the case and to establish the concrete elements that employers should consider if they intend to monitor their employees in order not to violate their right to private life at the workplace of the latter.

  12. Silica Gel-Mediated Organic Reactions under Organic Solvent-Free Conditions

    Directory of Open Access Journals (Sweden)

    Satoaki Onitsuka

    2012-09-01

    Full Text Available Silica gel was found to be an excellent medium for some useful organic transformations under organic solvent-free conditions, such as (1 the Friedel-Crafts-type nitration of arenes using commercial aqueous 69% nitric acid alone at room temperature, (2 one-pot Wittig-type olefination of aldehydes with activated organic halides in the presence of tributyl- or triphenylphosphine and Hunig’s base, and (3 the Morita-Baylis-Hillman reaction of aldehydes with methyl acrylate. After the reactions, the desired products were easily obtained in good to excellent yields through simple manipulation.

  13. A proposed abiotic reaction scheme for hydroxylamine and monochloramine under chloramination relevant drinking water conditions.

    Science.gov (United States)

    Wahman, David G; Speitel, Gerald E; Machavaram, Madhav V

    2014-09-01

    Drinking water monochloramine (NH2Cl) use may promote ammonia-oxidizing bacteria (AOB). AOB use (i) ammonia monooxygenase for biological ammonia (NH3) oxidation to hydroxylamine (NH2OH) and (ii) hydroxylamine oxidoreductase for NH2OH oxidation to nitrite. NH2Cl and NH2OH may react, providing AOB potential benefits and detriments. The NH2Cl/NH2OH reaction would benefit AOB by removing the disinfectant (NH2Cl) and releasing their growth substrate (NH3), but the NH2Cl/NH2OH reaction would also provide a possible additional inactivation mechanism besides direct NH2Cl reaction with cells. Because biological NH2OH oxidation supplies the electrons required for biological NH3 oxidation, the NH2Cl/NH2OH reaction provides a direct mechanism for NH2Cl to inhibit NH3 oxidation, starving the cell of reductant by preventing biological NH2OH oxidation. To investigate possible NH2Cl/NH2OH reaction implications on AOB, an understanding of the underlying abiotic reaction is first required. The present study conducted a detailed literature review and proposed an abiotic NH2Cl/NH2OH reaction scheme (RS) for chloramination relevant drinking water conditions (μM concentrations, air saturation, and pH 7-9). Next, RS literature based kinetics and end-products were evaluated experimentally between pHs 7.7 and 8.3, representing (i) the pH range for future experiments with AOB and (ii) mid-range pHs typically found in chloraminated drinking water. In addition, a (15)N stable isotope experiment was conducted to verify nitrous oxide and nitrogen gas production and their nitrogen source. Finally, the RS was slightly refined using the experimental data and an AQUASIM implemented kinetic model. A chloraminated drinking water relevant RS is proposed and provides the abiotic reaction foundation for future AOB biotic experiments. Published by Elsevier Ltd.

  14. Working Mothers and the State: Under Which Conditions do governments spend much on maternal employment supporting policies?

    NARCIS (Netherlands)

    Koole, K.; Vis, B.

    2012-01-01

    Over the last years, the level of spending on maternal employment supporting policies has risen in most countries. Still, the variation across governments in this level is substantial. Under which conditions do governments spend relatively much? Drawing on the critical mass literature, we argue that

  15. An efficient protocol for the synthesis of highly sensitive indole imines utilizing green chemistry: optimization of reaction conditions.

    Science.gov (United States)

    Nisar, Bushra; Rubab, Syeda Laila; Raza, Abdul Rauf; Tariq, Sobia; Sultan, Ayesha; Tahir, Muhammad Nawaz

    2018-04-11

    Novel and highly sensitive indole-based imines have been synthesized. Their synthesis has been compared employing a variety of protocols. Ultimately, a convenient, economical and high yielding set of conditions employing green chemistry have been designed for their synthesis.

  16. A versatile method for the preparation of conjugates of peptides with DNA/PNA/analog by employing chemo-selective click reaction in water

    Science.gov (United States)

    Gogoi, Khirud; Mane, Meenakshi V.; Kunte, Sunita S.; Kumar, Vaijayanti A.

    2007-01-01

    The specific 1,3 dipolar Hüisgen cycloaddition reaction known as ‘click-reaction’ between azide and alkyne groups is employed for the synthesis of peptide–oligonucleotide conjugates. The peptide nucleic acids (PNA)/DNA and peptides may be appended either by azide or alkyne groups. The cycloaddition reaction between the azide and alkyne appended substrates allows the synthesis of the desired conjugates in high purity and yields irrespective of the sequence and functional groups on either of the two substrates. The versatile approach could also be employed to generate the conjugates of peptides with thioacetamido nucleic acid (TANA) analog. The click reaction is catalyzed by Cu (I) in either water or in organic medium. In water, ∼3-fold excess of the peptide-alkyne/azide drives the reaction to completion in 2 h with no side products. PMID:17981837

  17. Influence of the reaction conditions on the enzyme catalyzed transesterification of castor oil

    DEFF Research Database (Denmark)

    Andrade, Thalles Allan; Errico, Massimiliano; Christensen, Knud Villy

    2017-01-01

    The identification of the influence of the reaction parameters is of paramount importance when defining a process design. In this work, non-edible castor oil was reacted with methanol to produce a possible component for biodiesel blends, using liquid enzymes as the catalyst. Temperature, alcohol......-to-oil molar ratio, enzyme and added water contents were the reaction parameters evaluated in the transesterification reactions. The optimal conditions, giving the optimal final FAME yield and FFA content in the methyl ester-phase was identified. At 35 °C, 6.0 methanol-to-oil molar ratio, 5 wt% of enzyme and 5...... wt% of water contents, 94 % of FAME yield and 6.1 % of FFA in the final composition were obtained. The investigation was completed with the analysis of the component profiles, showing that at least 8 hours are necessary to reach a satisfactory FAME yield together with a minor FFA content....

  18. Previous Employment and Job Satisfaction Conditions: The Case of Regional Administration

    Science.gov (United States)

    Amalia, Myronaki; Nikolaos, Antonakas

    2009-08-01

    In the present work we study the different dimensions of satisfaction and the way of constitution of satisfaction of an important sample of the employees in the Regional administration of Crete and in their connection with the variable of the previous employment. We found statistically important differences for the components of satisfaction from the life, collaboration in and outside from the department, in the social satisfaction and the variable of the years in the service (labour group with satisfaction than the other previous employment groups. In the other hand the group with many years in the service presents bigger satisfaction than the other groups. Finally, is important to note that the sample present some interesting characteristics.

  19. Factors that condition the spontaneous reporting of adverse drug reactions among nurses: an integrative review.

    Science.gov (United States)

    De Angelis, Alessia; Colaceci, Sofia; Giusti, Angela; Vellone, Ercole; Alvaro, Rosaria

    2016-03-01

    To describe and synthesise previous research on factors conditioning the spontaneous reporting of adverse drug reactions among nurses. Spontaneous reports of adverse drug reactions by health-care providers, are a main instrument for the continuous evaluation of the risk-benefit ratio of every drug. Under-reporting of adverse drug reactions by all health-care providers, in particular by nurses, is a major limitation to this system. An integrated review of the literature was conducted using MEDLINE, CINAHL, Embase, Scopus databases and Google Scholar. After evaluation for appropriateness related to inclusion/exclusion criteria, 16 studies were included in the final analysis and synthesis. Two factors emerged from the study: (1) intrinsic factors related to nurses' knowledge and attitudes; (2) extrinsic factors related to nurses' interaction with health-care organisations and to the relationship between nurses and physicians. Nurses' attitudes that hinder reporting include ignorance, insecurity, fear and lethargy. Nurses are not fully aware of their role in adverse drug reaction reporting. Nurses must acquire greater knowledge to implement specific skills into their daily clinical practice. To improve nurses' reporting of adverse drug reactions, it is necessary to develop management approaches that modify both intrinsic and extrinsic factors. © 2015 John Wiley & Sons Ltd.

  20. Safer operating conditions and optimal scaling-up process for cyclohexanone peroxide reaction

    International Nuclear Information System (INIS)

    Zang, Na; Qian, Xin-Ming; Liu, Zhen-Yi; Shu, Chi-Min

    2015-01-01

    Highlights: • Thermal hazard of cyclohexanone peroxide reaction was measured by experimental techniques. • Levenberg–Marquardt algorithm was adopted to evaluate kinetic parameters. • Safer operating conditions at laboratory scale were acquired by BDs and TDs. • The verified safer operating conditions were used to obtain the optimal scale-up parameters applied in industrial plants. - Abstract: The cyclohexanone peroxide reaction process, one of the eighteen hazardous chemical processes identified in China, is performed in indirectly cooled semibatch reactors. The peroxide reaction is added to a mixture of hydrogen peroxide and nitric acid, which form heterogeneous liquid–liquid systems. A simple and general procedure for building boundary and temperature diagrams of peroxide process is given here to account for the overall kinetic expressions. Such a procedure has been validated by comparison with experimental data. Thermally safer operating parameters were obtained at laboratory scale, and the scaled-up procedure was performed to give the minimum dosing time in an industrial plant, which is in favor of maximizing industrial reactor productivity. The results are of great significance for governing the peroxide reaction process apart from the thermal runaway region. It also greatly aids in determining optimization on operating parameters in industrial plants.

  1. Assessing the reaction conditions to mediate the milkfat-soybean oil enzymatic interesterification

    Directory of Open Access Journals (Sweden)

    Ariela Veloso de Paula

    Full Text Available Summary A food grade lipase from Rhizopus oryzae immobilized on a hybrid polysiloxane-polyvinyl alcohol matrix (SiO2-PVA was used as the biocatalyst to mediate the interesterification reactions of a blend containing 65% milkfat and 35% soybean oil. All the reactions occurred in an inert nitrogen atmosphere in cylindrical glass reactors (80 mL with 40 g of the milkfat-soybean oil blend. The influence of the following variables was evaluated: biocatalyst loading (250-1500 activity units per gram of blend, biocatalyst moisture content (5-20%, temperature (45-60 °C and incubation time (2-48 h. The reactions were monitored by determining the free fatty acid content, triacylglycerol (TAGs composition in carbon species, and the consistency of the interesterified (IE products. The reaction conditions were set based on the parameters that provided a high interesterification yield and good consistency of the final product within the ideal range (200 to 800 gf cm-2. Hence the best results were obtained using a biocatalyst loading of 500 U g-1 of blend with 10% moisture content at 45 °C for 4 h. Under these conditions the consistency of the interesterified product was 539.7 ± 38 gf cm-2. The results demonstrated the potential of the immobilized lipase to alter the TAGs profile of the milkfat-soybean oil blend, allowing for the production of structured lipids.

  2. The kinetics of dolomite reaction rim growth under isostatic and non-isostatic pressure conditions

    Science.gov (United States)

    Helpa, V.; Rybacki, E.; Morales, L. G.; Abart, R.; Dresen, G. H.

    2013-12-01

    During burial and exhumation, rocks are simultaneously exposed to metamorphic reactions and tectonic stresses. Therefore, the reaction rate of newly formed minerals may depend on chemical and mechanical driving forces. Here, we investigate the reaction kinetics of dolomite (CaMg[CO3]2) rim growth by solid-state reactions experiments on oriented calcite (CaCO3) and magnesite (MgCO3) single crystals under isostatic and non-isostatic pressure conditions. Cylindrical samples of 3-5 mm length and 7 mm diameter were drilled and polished perpendicular to the rhombohedral cleavage planes of natural clear crystals. The tests were performed using a Paterson-type deformation apparatus at P = 400 MPa confining pressure, temperatures, T, between 750 and 850°C, and reaction durations, t, of 2 - 146 h to calculate the kinetic parameters of dolomite rim growth under isostatic stress conditions. For non-isostatic reaction experiments we applied in addition differential stresses, σ, up to 40 MPa perpendicular to the contact interface at T = 750°C for 4 - 171 h duration, initiating minor inelastic deformation of calcite. The thickness of the resulting dolomite reaction rims increases linearly with the square root of time, indicating a diffusion-controlled reaction. The rims consist of two different textural domains. Granular dolomite grains (≈ 2 -5 μm grain size) form next to calcite and elongated palisade-shaped grains (1-6 μm diameter) grow perpendicular to the magnesite interface. Texture measurements with the electron backscatter diffraction technique indicate that the orientations of dolomite grains are mainly influenced by the orientation of the calcite educt crystal, in particular in the granular rim. To some extent, the texture of dolomite palisades is also influenced by the orientation of magnesite. The thickness of the two individual layers increases with temperature. At 400 MPa isostatic pressure, T = 750°C and t = 29 hours, a 5 μm thick granular dolomite layer

  3. The assessment of chronic health conditions on work performance, absence, and total economic impact for employers.

    Science.gov (United States)

    Collins, James J; Baase, Catherine M; Sharda, Claire E; Ozminkowski, Ronald J; Nicholson, Sean; Billotti, Gary M; Turpin, Robin S; Olson, Michael; Berger, Marc L

    2005-06-01

    The objective of this study was to determine the prevalence and estimate total costs for chronic health conditions in the U.S. workforce for the Dow Chemical Company (Dow). Using the Stanford Presenteeism Scale, information was collected from workers at five locations on work impairment and absenteeism based on self-reported "primary" chronic health conditions. Survey data were merged with employee demographics, medical and pharmaceutical claims, smoking status, biometric health risk factors, payroll records, and job type. Almost 65% of respondents reported having one or more of the surveyed chronic conditions. The most common were allergies, arthritis/joint pain or stiffness, and back or neck disorders. The associated absenteeism by chronic condition ranged from 0.9 to 5.9 hours in a 4-week period, and on-the-job work impairment ranged from a 17.8% to 36.4% decrement in ability to function at work. The presence of a chronic condition was the most important determinant of the reported levels of work impairment and absence after adjusting for other factors (P < 0.000). The total cost of chronic conditions was estimated to be 10.7% of the total labor costs for Dow in the United States; 6.8% was attributable to work impairment alone. For all chronic conditions studied, the cost associated with performance based work loss or "presenteeism" greatly exceeded the combined costs of absenteeism and medical treatment combined.

  4. To work despite chronic health conditions: a qualitative study of workers at the Swedish Public Employment Service.

    Science.gov (United States)

    Hjärtström, Carina; Lindahl Norberg, Annika; Johansson, Gun; Bodin, Theo

    2018-04-20

    Achieving a sustainable, healthy and long working life is key prerequisite for meeting the demographic challenge posed by an ageing population so that more people can work on into their later years. The objective of this study is to explore the relationship between work and chronic health conditions in a group of employees aged 50-64 years with a focus on factors that enable them to continue to work. Ten white-collar workers with one or more chronic health conditions at the Swedish Public Employment Service participated in the study. A qualitative method with semistructured in-depth interviews was used to collect data. This study shows that factors enabling people with chronic health conditions to work include adaptation of the work situation by task-shifting as well as provision of physical aids. Our study suggest that the changes often come at the employee's initiative; hence, there is potential for greater involvement from the employer, healthcare agencies and the social insurance fund in making it easier for employees to adapt their work situation and in providing information regarding available support. It confirms findings in earlier studies that health plays an important part and also that self-confidence and motivation are significant factors contributing to workers being able and wanting to continue working. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  5. The association of mental health conditions with employment, interpersonal, and subjective functioning after intimate partner violence.

    Science.gov (United States)

    Beck, J Gayle; Clapp, Joshua D; Jacobs-Lentz, Jason; McNiff, Judiann; Avery, Megan; Olsen, Shira A

    2014-11-01

    This study explored the associations of posttraumatic stress disorder (PTSD), generalized anxiety disorder (GAD), and depressive symptoms with employment, social support, and subjective functioning in 100 women who were seeking mental health assistance after intimate partner violence. Depressive disorders showed significant associations with low levels of social support, diminished self-esteem, reduced quality of life, and elevated negative social problem-solving orientation. PTSD severity was significantly associated with low self-esteem and elevated negative problem orientation, while severity of GAD was only associated with negative problem orientation. Results are discussed in light of current service models for women who have experienced intimate partner violence. © The Author(s) 2014.

  6. Gender inequalities in occupational health related to the unequal distribution of working and employment conditions: a systematic review

    Science.gov (United States)

    2013-01-01

    Introduction Gender inequalities exist in work life, but little is known about their presence in relation to factors examined in occupation health settings. The aim of this study was to identify and summarize the working and employment conditions described as determinants of gender inequalities in occupational health in studies related to occupational health published between 1999 and 2010. Methods A systematic literature review was undertaken of studies available in MEDLINE, EMBASE, Sociological Abstracts, LILACS, EconLit and CINAHL between 1999 and 2010. Epidemiologic studies were selected by applying a set of inclusion criteria to the title, abstract, and complete text. The quality of the studies was also assessed. Selected studies were qualitatively analysed, resulting in a compilation of all differences between women and men in the prevalence of exposure to working and employment conditions and work-related health problems as outcomes. Results Most of the 30 studies included were conducted in Europe (n=19) and had a cross-sectional design (n=24). The most common topic analysed was related to the exposure to work-related psychosocial hazards (n=8). Employed women had more job insecurity, lower control, worse contractual working conditions and poorer self-perceived physical and mental health than men did. Conversely, employed men had a higher degree of physically demanding work, lower support, higher levels of effort-reward imbalance, higher job status, were more exposed to noise and worked longer hours than women did. Conclusions This systematic review has identified a set of working and employment conditions as determinants of gender inequalities in occupational health from the occupational health literature. These results may be useful to policy makers seeking to reduce gender inequalities in occupational health, and to researchers wishing to analyse these determinants in greater depth. PMID:23915121

  7. Gender inequalities in occupational health related to the unequal distribution of working and employment conditions: a systematic review.

    Science.gov (United States)

    Campos-Serna, Javier; Ronda-Pérez, Elena; Artazcoz, Lucia; Moen, Bente E; Benavides, Fernando G

    2013-08-05

    Gender inequalities exist in work life, but little is known about their presence in relation to factors examined in occupation health settings. The aim of this study was to identify and summarize the working and employment conditions described as determinants of gender inequalities in occupational health in studies related to occupational health published between 1999 and 2010. A systematic literature review was undertaken of studies available in MEDLINE, EMBASE, Sociological Abstracts, LILACS, EconLit and CINAHL between 1999 and 2010. Epidemiologic studies were selected by applying a set of inclusion criteria to the title, abstract, and complete text. The quality of the studies was also assessed. Selected studies were qualitatively analysed, resulting in a compilation of all differences between women and men in the prevalence of exposure to working and employment conditions and work-related health problems as outcomes. Most of the 30 studies included were conducted in Europe (n=19) and had a cross-sectional design (n=24). The most common topic analysed was related to the exposure to work-related psychosocial hazards (n=8). Employed women had more job insecurity, lower control, worse contractual working conditions and poorer self-perceived physical and mental health than men did. Conversely, employed men had a higher degree of physically demanding work, lower support, higher levels of effort-reward imbalance, higher job status, were more exposed to noise and worked longer hours than women did. This systematic review has identified a set of working and employment conditions as determinants of gender inequalities in occupational health from the occupational health literature. These results may be useful to policy makers seeking to reduce gender inequalities in occupational health, and to researchers wishing to analyse these determinants in greater depth.

  8. Transesterification of soybean oil with methanol and acetic acid at lower reaction severity under subcritical conditions

    International Nuclear Information System (INIS)

    Go, Alchris Woo; Sutanto, Sylviana; NguyenThi, Bich Thuyen; Cabatingan, Luis K.; Ismadji, Suryadi; Ju, Yi-Hsu

    2014-01-01

    Highlights: • (trans)Esterification of oils under subcritical conditions. • Acetic acid as catalyst and co-solvent in biodiesel production. • Influence of reactor hydrodynamic (loading and stirring) on FAME yield. • High methyl ester yield can be obtained at less severe reaction conditions. - Abstract: Soybean oil (56–80 g) was reacted with methanol (40–106 mL) to produce fatty acid methyl ester in the presence of 1–6% acetic acid under subcritical condition at 250 °C. Stirring and loading of the reaction system affected the yield and severity of the process. The presence of acetic acid improved the yield of FAME from 32.1% to 89.5% at a methanol to oil molar ratio of 20 mL/g. Acetic acid was found to act strongly as an acid catalyst and to some extent improved the solubility between oil and methanol. Reaction pressure higher than the supercritical pressure of methanol (7.85 MPa) was not required to achieve high FAME yield (89.5–94.8%) in short time (30–60 min)

  9. The effect of catalytic reaction conditions on the incorporation of tritium in unsaturated compounds

    Energy Technology Data Exchange (ETDEWEB)

    Shevchenko, V P; Nagayev, I Yu; Myasoedov, N F [AN SSSR, Moscow (USSR). Inst. Molekulyarnoj Genetiki

    1989-10-01

    We have obtained multiple-tritium-labelled 5-{alpha}-androstan-3-one, dihydropicrotoxin, dimethyl-propyl-3-chloro-butyl-ammonium chloride, 2,2-di(trifluoromethyl)-3,3-dicyanobicyclohept(2,2,1)ane, dihydroalprenolol, undecanoic acid, dihydro-m,m'-di-tert.-butyl-p-coumaric acid and dihydrofusicoccin. By varying the conditions for the hydrogenation of terminal double bonds, one can considerably increase the molar radioactivity of such compounds through isotopic exchange. We discuss some tentative explanations of the effect of the labelling reaction conditions upon the synthesis of compounds with desired properties. (author).

  10. The effect of catalytic reaction conditions on the incorporation of tritium in unsaturated compounds

    International Nuclear Information System (INIS)

    Shevchenko, V.P.; Nagayev, I.Yu.; Myasoedov, N.F.

    1989-01-01

    We have obtained multiple-tritium-labelled 5-α-androstan-3-one, dihydropicrotoxin, dimethyl-propyl-3-chloro-butyl-ammonium chloride, 2,2-di(trifluoromethyl)-3,3-dicyanobicyclohept[2,2,1]ane, dihydroalprenolol, undecanoic acid, dihydro-m,m'-di-tert.-butyl-p-coumaric acid and dihydrofusicoccin. By varying the conditions for the hydrogenation of terminal double bonds, one can considerably increase the molar radioactivity of such compounds through isotopic exchange. We discuss some tentative explanations of the effect of the labelling reaction conditions upon the synthesis of compounds with desired properties. (author)

  11. Conditioning of radioactive ash residue in a wave of solid-phase exothermal reactions

    International Nuclear Information System (INIS)

    Karlina, O.K.; Varlakova, G.A.; Ozhovan, M.I.; Tivanskij, V.M.; Dmitriev, S.A.

    2001-01-01

    The abilities for utilization of exothermic reaction heat in solid phase for conditioning the ash residue produced as a result of solid radioactive waste burning are analyzed. It is shown that the process of ash residue making monolithic with obtaining the glass-like finish product containing 50-60 mass % of ash residue which meets the requirements for solidified radioactive wastes may be realized without energy supplying from external heat sources. The conditioning is realized in a special crucible furnace-container designed not only for the process conducting but also for subsequent storage or disposal of the finish product [ru

  12. Interface conditions for fast-reaction fronts in wet porous mineral materials: the case of concrete carbonation

    NARCIS (Netherlands)

    Muntean, A.; Böhm, M.

    2009-01-01

    Reaction–diffusion processes, where slow diffusion balances fast reaction, usually exhibit internal loci where the reactions are concentrated. Some modeling and simulation aspects of using kinetic free-boundary conditions to drive fast carbonation reaction fronts into unsaturated porous cement-based

  13. Early-life conditions and health at older ages: The mediating role of educational attainment, family and employment trajectories.

    Science.gov (United States)

    Arpino, Bruno; Gumà, Jordi; Julià, Albert

    2018-01-01

    We examine to what extent the effect of early-life conditions (health and socioeconomic status) on health in later life is mediated by educational attainment and life-course trajectories (fertility, partnership, employment). Using data from the Survey of Health, Ageing and Retirement in Europe (N = 12,034), we apply, separately by gender, multichannel sequence analysis and cluster analysis to obtain groups of similar family and employment histories. The KHB method is used to disentangle direct and indirect effects of early-life conditions on health. Early-life-conditions indirectly impact on health in later life as result of their influence on education and family and employment trajectories. For example, between 22% and 42% of the effect of low parental socio-economic status at childhood on the three considered health outcomes at older age is explained by educational attainment for women. Even higher percentages are found for men (35% - 57%). On the contrary, the positive effect of poor health at childhood on poor health at older ages is not significantly mediated by education and life-course trajectories. Education captures most of the mediating effect of parental socio-economic status. More specifically, between 66% and 75% of the indirect effect of low parental socio-economic status at childhood on the three considered health outcomes at older age is explained by educational attainment for women. Again, higher percentages are found for men (86% - 93%). Early-life conditions, especially socioeconomic status, influence family and employment trajectories indirectly through their impact on education. We also find a persistent direct impact of early-life conditions on health at older ages. Our findings demonstrate that early-life experiences influence education and life-course trajectories and health in later life, suggesting that public investments in children are expected to produce long lasting effects on people's lives throughout the different phases of their

  14. Employment and working conditions of the Ukranian working-age population

    DEFF Research Database (Denmark)

    Mazhak, Iryna

    2017-01-01

    the number of those who worked overtime for additional payment. In general, more males tended to work overtime for additional payment than females. Half (52%) of the respondents considered that they had reached a balance between professional and private life, 37% reported lack of time for private life, 4....... 30% of the respondents worked with shifts, 70% – with no shifts. 22% worked at night, 78% – did not work at night. Twice as many males worked at night compared to females. Almost half (47%) of the respondents stated that their reward at work depended on their efforts and productivity, almost the same......According to the research carried out by the Sociological Group "Rating" in December 2016, 60% of the respondents were employed, 40% - unemployed. Among the unemployed, one-third (32%) – pensioners, 27% – housekeeping and childcare, 13% – students, 21% – unemployed and looking for work, 6...

  15. Transaction component of exogenous factors of influence upon employment under conditions of globalisation of economy

    Directory of Open Access Journals (Sweden)

    Glushach Anna V.

    2013-03-01

    Full Text Available The goal of the article lies in identification of influence of globalisation upon efficiency of financial and loan instruments that ensure regulation and stimulation of employment and the role of transaction costs in these processes. To achieve the goal, the article shows how globalisation processes, which take place in the sphere of the financial sector, influence the real economy and employment of the population, identifies positive and negative sides of this influence. The article conducts analysis of causes and effects of the financial and economic crisis from the point of view of the theory of transaction costs, in the process of which the role of specific types of these costs in the processes that took place was ascertained. In the course of the study the article reveals negative influence of the growing disproportion between the public and private transaction costs of the risks of financial and economic instability, especially in the countries with the transformation economy, and justifies the necessity of stabilising mechanisms of the international financial market with the aim of elimination of the marked transaction disproportions such as introduction of a special tax on financial transactions or establishment of the double currency course: less flexible – for servicing trading operations, and more flexible – for regulation of financial flows. Studies of negative effects of integration processes allowed formation of directions of the state policy, which would prevent dangerous consequences of interference of the foreign capital with the financial sector and would protect the Ukrainian labour market from influence of negative effects of integration processes.

  16. The methods for diagnostic of the technical condition of vehicles employing high precise satellite data

    Directory of Open Access Journals (Sweden)

    Anatoliy KULIK

    2014-03-01

    Full Text Available The paper presents a methodology for diagnostic of the technical condition of vehicle. The high accuracy of the actual trajectory of the transport aggregate (TA is provided by the use of local differential mode of global navigation satellite system (GNSS. Comparing the real and rational trajectories will determine the kinematic and dynamic characteristics of the car.

  17. Occupational reporiductive system diseases in female workers employed at worplaces with harmful working conditions

    Directory of Open Access Journals (Sweden)

    M.A. Fesenko

    2017-09-01

    Full Text Available The paper outlines the data obtained in the course of long-term research dedicated to studying the extent to which re-productive system pathologies in workers with high-risk occupations are occupationally induced. Their peculiarity is joint impacts of various occupational factors (for example, impacts exerted by chemicals together with physical and biological factors, and labor hardness and intensity as well on a female body. Our research goal was to examine the extent to which reproductive system pathologies in workers with high-risk occupations were occupationally induced. To achieve it, we applied statistical estimate of correlation between health disorders and work. Our occupational group included a number of occupations with harmful or hazardous working conditions in civil en-gineering, metallurgy, chemical industry, polymer-processing industry, and health care as well. As a rule, working condi-tions class of workers from the examined groups varied from 3.1 to 3.3; and occupation with permissible working conditions were used as a comparative group. The research results revealed that there are certain occupations with high risk of reproductive health disorders evolvement and infants development pathologies evolvement. They are: – model makers and checkers in civil engineering and crane operators at a metallurgic plant; – analysts at chemical analysis laboratories, chemical engineers in chemical industry (including petrochemical plants, polymer-processing plants, and organic synthesis plants; – surgeons, obstetrician-gynecologists, midwives, surgical nurses working in in-patient departments. Estimate of correlation and occupational dependence of reproductive system diseases on working conditions revealed that women with harmful working conditions (3.1–3.3 hazard class had defective pregnancies or labor pathologies which had strong and average correlation with working conditions. Health disorders in newborns were estimated as per very

  18. Kinetics and Mechanism of the Reaction of Hydoxyl Radicals with Acetonitrile under Atmospheric Conditions

    Science.gov (United States)

    Hynes, A. J.; Wine, P. H.

    1997-01-01

    The pulsed laser photolysis-pulsed laser induced fluorescence technique has been employed to determine absolute rate coefficients for the reaction OH + CH3CN (1) and its isotopic variants, OH + CD3CN (2), OD + CH3CN (3), and OD + CD3CN (4). Reactions 1 and 2 were studied as a function of pressure and temperature in N2, N2/O2, and He buffer gases. In the absence of O2 all four reactions displayed well-behaved kinetics with exponential OH decays and pseudo-first rate constants which were proportional to substrate concentration. Data obtained in N2 over the range 50-700 Torr at 298 K are consistent with k(sub 1), showing a small pressure dependence. The Arrhenius expression obtained by averaging data at all pressures in k(sub 1)(T) = (1.1(sup +0.5)/(sub -0.3)) x 10(exp -12) exp[(-1130 +/- 90)/T] cu cm /(molecule s). The kinetics of reaction 2 are found to be pressure dependent with k(sub 2) (298 K) increasing from (1.21 +/- 0.12) x 10(exp -14) to (2.16 +/- 0.11) x 10(exp -14) cm(exp 3)/ (molecule s) over the pressure range 50-700 Torr of N2 at 298 K. Data at pressures greater than 600 Torr give k(sub 2)(T) = (9.4((sup +13.4)(sub -5.0))) x 10(exp -13) exp[(-1180 +/- 250)/T] cu cm/(molecule s). The rates of reactions 3 and 4 are found to be independent of pressure over the range 50-700 Torr of N2 with 298 K rate coefficient given by k(sub 3) =(3.18 +/- 0.40) x 10(exp -14) cu cm/(molecule s) and k(sub 4) = (2.25 +/-0.28) x 10(exp -14) cu cm/(molecule s). In the presence of O2 each reaction shows complex (non-pseudo-first-order) kinetic behavior and/or an apparent decrease in the observed rate constant with increasing [O2], indicating the presence of significant OH or OD regeneration. Observation of regeneration of OH in (2) and OD in (3) is indicative of a reaction channel which proceeds via addition followed by reaction of the adduct, or one of its decomposition products, with O2. The observed OH and OD decay profiles have been modeled by using a simple mechanistic

  19. Employment conditions and work-related stressors are associated with menopausal symptom reporting among perimenopausal and postmenopausal women.

    Science.gov (United States)

    Bariola, Emily; Jack, Gavin; Pitts, Marian; Riach, Kathleen; Sarrel, Philip

    2017-03-01

    While many women undergo menopausal transition while they are in paid employment, the effect of poor working conditions on women's experience of the menopause has received scant empirical attention. We examined associations between employment conditions, work-related stressors, and menopausal symptom reporting among perimenopausal and postmenopausal working women. Data were drawn from an online survey conducted between 2013 and 2014 involving 476 perimenopausal and postmenopausal women working in the higher education sector in Australia. Survey questions assessed demographics; health-related variables; menopausal symptom reporting; employment status; presence of flexible working hours; presence of temperature control; job autonomy; and supervisor support. A forced entry multivariable regression analysis revealed that high supervisor support (β = -0.10, P = 0.04), being employed on a full-time basis (β = -0.11, P = 0.02), and having control over workplace temperature (β = -0.11, P = 0.02) were independently associated with lower menopausal symptom reporting. These findings may help inform the development of tailored occupational health policies and programs that cater for the needs of older women as they transition through menopause in the workplace.

  20. Test plan for reactions between spent fuel and J-13 well water under unsaturated conditions

    International Nuclear Information System (INIS)

    Finn, P.A.; Wronkiewicz, D.J.; Hoh, J.C.; Emery, J.W.; Hafenrichter, L.D.; Bates, J.K.

    1993-01-01

    The Yucca Mountain Site Characterization Project is evaluating the long-term performance of a high-level nuclear waste form, spent fuel from commercial reactors. Permanent disposal of the spent fuel is possible in a potential repository to be located in the volcanic tuff beds near Yucca Mountain, Nevada. During the post-containment period the spent fuel could be exposed to water condensation since of the cladding is assumed to fail during this time. Spent fuel leach (SFL) tests are designed to simulate and monitor the release of radionuclides from the spent fuel under this condition. This Test Plan addresses the anticipated conditions whereby spent fuel is contacted by small amounts of water that trickle through the spent fuel container. Two complentary test plans are presented, one to examine the reaction of spent fuel and J-13 well water under unsaturated conditions and the second to examine the reaction of unirradiated UO 2 pellets and J-13 well water under unsaturated conditions. The former test plan examines the importance of the water content, the oxygen content as affected by radiolysis, the fuel burnup, fuel surface area, and temperature. The latter test plant examines the effect of the non-presence of Teflon in the test vessel

  1. Description of the equilibrium conditions of chemical reactions in various solvents

    International Nuclear Information System (INIS)

    Roehl, H.

    1983-01-01

    Empirical knowledge is taken as the basis for establishing a method to predict the equilibrium conditions of reactions of macrocyclic polyethers and monovalent metal cations in various solvents. The reactions in the solvents under review can be well described by the donor number DN according to Gutmann, and by the parameters alpha and pi-asterisk for the H bonding donor and polarity/polarisability, respectively, using a three-parameter equation according to Kamlet/Taft. This applies to both protic and aprotic solvents. The calculations rely on data found in the literature and on own experimental results obtained by microcalorimetric examinations. The evaluation methods evolved for this purpose also allow, by means of additional dilution experiments, to convert the ''integral'', microcalorimetrically obtained complex stability constants, (i.e. those non-discriminating between different types of state such as ions or ion pairs) to the corresponding ''differentiating'' constants (referring to purely ionic quantities), and this applied to the various solvents used. The method does not use foreign ions and can thus also be applied to those cases for which the normal standardisation of reaction conditions published in the literature cannot be maintained (e.g. for reasons of solubility). In some cases it was possible to obtain additional information on the dissociation behaviour of the salts used, which revealed differently strong inclination to form higher aggregations in solution, as shown e.g. by the strong concentration dependence of the salt ion pair dissociation constants obtained. (orig./EF) [de

  2. Ablation characteristics and reaction mechanism of insulation materials under slag deposition condition

    Science.gov (United States)

    Guan, Yiwen; Li, Jiang; Liu, Yang

    2017-07-01

    Current understanding of the physical and chemical processes involved in the ablation of insulation materials by highly aluminized solid propellants is limited. The study on the heat transfer and ablation principle of ethylene propylene diene monomer (EPDM) materials under slag deposition condition is essential for future design or modification of large solid rocket motors (SRMs) for launch application. In this paper, the alumina liquid flow pattern and the deposition principle in full-scale SRM engines are discussed. The interaction mechanism between the alumina droplets and the wall are analyzed. Then, an experimental method was developed to simulate the insulation material ablation under slag deposition condition. Experimental study was conducted based on a laboratory-scale device. Meanwhile, from the analysis of the cross-sectional morphology and chemical composition of the charring layer after ablation, the reaction mechanism of the charring layer under deposition condition was discussed, and the main reaction equation was derived. The numerical simulation and experimental results show the following. (i) The alumina droplet flow in the deposition section of the laboratory-scale device is similar to that of a full-scale SRM. (ii) The charring layer of the EPDM insulator displays a porous tight/loose structure under high-temperature slag deposition condition. (iii) A seven-step carbothermal reduction in the alumina is derived and established under high-pressure and high-temperature environment in the SRM combustion chamber. (iv) The analysis using thermodynamic software indicates that the reaction of the alumina and charring layer initially forms Al4C3 during the operation. Then, Al element and Al2OC compound are subsequently produced with the reduction in the release of gas CO as well with continuous environmental heating.

  3. Photo catalytic reduction of benzophenone on TiO2: Effect of preparation method and reaction conditions

    International Nuclear Information System (INIS)

    Albiter E, E.; Valenzuela Z, M. A.; Alfaro H, S.; Flores V, S. O.; Rios B, O.; Gonzalez A, V. J.; Cordova R, I.

    2010-01-01

    The photo catalytic reduction of benzophenone was studied focussing on improving the yield to benzhydrol. TiO 2 was synthesized by means of a hydrothermal technique. TiO 2 (Degussa TiO 2 -P25) was used as a reference. Catalysts were characterized by X-ray diffraction and nitrogen physisorption. The photo catalytic reduction was carried out in a batch reactor at 25 C under nitrogen atmosphere, acetonitrile as solvent and isopropanol as electron donor. A 200 W Xe-Hg lamp (λ= 360 nm) was employed as irradiation source. The chemical composition of the reaction system was determined by HPLC. Structural and textural properties of the synthesized TiO 2 depended on the type of acid used during sol formation step. Using HCl, a higher specific surface area and narrower pore size distribution of TiO 2 was obtained in comparison with acetic acid. As expected, the photochemical reduction of benzophenone yielded benzopinacol as main product, whereas, benzhydrol is only produced in presence of TiO 2 (i.e. photo catalytic route). In general, the hydrothermally synthesized catalysts were less active and with a lower yield to benzhydrol. The optimal reaction conditions to highest values of benzhydrol yield (70-80%) were found at 2 g/L (catalyst loading) and 0.5 m M of initial concentration of benzophenone, using commercial TiO 2 -P25. (Author)

  4. Photo catalytic reduction of benzophenone on TiO{sub 2}: Effect of preparation method and reaction conditions

    Energy Technology Data Exchange (ETDEWEB)

    Albiter E, E.; Valenzuela Z, M. A.; Alfaro H, S.; Flores V, S. O.; Rios B, O.; Gonzalez A, V. J.; Cordova R, I., E-mail: mavalenz@ipn.m [IPN, Escuela Superior de Ingenieria Quimica e Industrias Extractivas, Laboratorio de Catalisis y Materiales, Zacatenco, 07738 Mexico D. F. (Mexico)

    2010-07-01

    The photo catalytic reduction of benzophenone was studied focussing on improving the yield to benzhydrol. TiO{sub 2} was synthesized by means of a hydrothermal technique. TiO{sub 2} (Degussa TiO{sub 2}-P25) was used as a reference. Catalysts were characterized by X-ray diffraction and nitrogen physisorption. The photo catalytic reduction was carried out in a batch reactor at 25 C under nitrogen atmosphere, acetonitrile as solvent and isopropanol as electron donor. A 200 W Xe-Hg lamp ({lambda}= 360 nm) was employed as irradiation source. The chemical composition of the reaction system was determined by HPLC. Structural and textural properties of the synthesized TiO{sub 2} depended on the type of acid used during sol formation step. Using HCl, a higher specific surface area and narrower pore size distribution of TiO{sub 2} was obtained in comparison with acetic acid. As expected, the photochemical reduction of benzophenone yielded benzopinacol as main product, whereas, benzhydrol is only produced in presence of TiO{sub 2} (i.e. photo catalytic route). In general, the hydrothermally synthesized catalysts were less active and with a lower yield to benzhydrol. The optimal reaction conditions to highest values of benzhydrol yield (70-80%) were found at 2 g/L (catalyst loading) and 0.5 m M of initial concentration of benzophenone, using commercial TiO{sub 2}-P25. (Author)

  5. Reaction

    African Journals Online (AJOL)

    abp

    19 oct. 2017 ... Reaction to Mohamed Said Nakhli et al. concerning the article: "When the axillary block remains the only alternative in a 5 year old child". .... Bertini L1, Savoia G, De Nicola A, Ivani G, Gravino E, Albani A et al ... 2010;7(2):101-.

  6. Thermal aromatic Claisen rearrangement and Strecker reaction of alkyl(allyl-aryl ethers under green reaction conditions: Efficient and clean preparation of ortho-allyl phenols (naphthols and alkyl(allyloxyarene-based γ-amino nitriles

    Directory of Open Access Journals (Sweden)

    Kheila N. Silgado-Gómez

    2017-11-01

    Full Text Available Chemical transformations of 13 diverse allyl(alkyl-aryl ethers, easily prepared using Williamson reaction of different hydroxyarenes and allyl bromide and alkyl (n-butyl, n-octyl bromides, were studied. Thermal aromatic Claisen rearrangement of allyl-aryl ethers to obtain ortho-allyl phenols (naphthols employing propylene carbonate as a nontoxic and biodegradable solvent was described for the first time. The use of this green solvent allowed to enhance notably product yields and reduce significantly the reaction time comparing with the use of 1,2-dichlorobenzene, toxic solvent, which is traditionally employed in this type of Claisen rearrangement. Three-component Strecker reaction of selected alkyl(allyl-aryl ethers with formyl function on aryl fragment and, piperidine and potassium cyanide in the presence of sulfuric acid supported on silica gel (SSA, SiO2-O-SO3H under mild reaction conditions was used in the preparation of new γ-amino nitriles, analogues of alkaloid girgensohnine [2-(4-hydroxyphenyl-2-(piperidin-1-ylacetonitrile], a perspective biological model in the search for new insecticidal agrochemicals against Aedes aegypti. The use of SSA, an inexpensive and reusable solid catalyst, allowed to obtain new series of 2-[4-alkyl(allyloxyphenyl]-2-(piperidin-1-ylacetonitriles in short time at room temperature with good yields.

  7. Employment-related difficulties and distressed living condition in patients with hepatitis B virus: A qualitative and quantitative study

    Directory of Open Access Journals (Sweden)

    Taeko Oka

    2017-06-01

    Full Text Available Abstract Background In Japan, an estimated 400,000 people have the hepatitis B virus (HBV, many of whom were infected as a result of group vaccinations. People with HBV face many challenges, including disease progression, employment-related difficulties, and increased medical expenses. The relationship between HBV victims’ daily life suffering and poverty associated with HBV-related employment changes has not been examined. We aimed to clarify the employment-related hardships experienced by Japanese HBV victims, and the relationships between these hardships and daily life suffering, including poverty, through qualitative and quantitative analyses. Methods The study population comprised 11,046 people infected with HBV via group vaccination who filed lawsuits in Japan’s District Courts by 2014. First, we conducted a qualitative study (2013 using the KJ method, with 107 participants (68 men, mean age 58.9 years; 39 women, mean age 55.3 years. Semi-structured interviews were conducted covering participants’ current condition, treatment, medical expenses, and life difficulties (employment- and family-related problems. In 2014, we conducted a quantitative study. We mailed questionnaires to the entire study population, investigating the topics covered in the interviews (response rate 60.1%. Daily life suffering was determined by responses to the question “What do you think about your everyday life situation?” We performed binomial logistic regression analyses to verify the relationships between daily life suffering and disease, employment, and income status. Results Interview data were integrated into seven islands: intention to work, lack of understanding of HBV in the workplace, inability to buy life insurance, burden due to medical expenses, life failure, dissatisfaction with the system, and wishing for life balance. The quantitative analyses showed significant positive correlations between daily life suffering and liver cancer (odds

  8. Effects of network dissolution changes on pore-to-core upscaled reaction rates for kaolinite and anorthite reactions under acidic conditions

    KAUST Repository

    Kim, Daesang

    2013-11-01

    We have extended reactive flow simulation in pore-network models to include geometric changes in the medium from dissolution effects. These effects include changes in pore volume and reactive surface area, as well as topological changes that open new connections. The computed changes were based upon a mineral map from an X-ray computed tomography image of a sandstone core. We studied the effect of these changes on upscaled (pore-scale to core-scale) reaction rates and compared against the predictions of a continuum model. Specifically, we modeled anorthite and kaolinite reactions under acidic flow conditions during which the anorthite reactions remain far from equilibrium (dissolution only), while the kaolinite reactions can be near-equilibrium. Under dissolution changes, core-scale reaction rates continuously and nonlinearly evolved in time. At higher injection rates, agreement with predictions of the continuum model degraded significantly. For the far-from-equilibrium reaction, our results indicate that the ability to correctly capture the heterogeneity in dissolution changes in the reactive mineral surface area is critical to accurately predict upscaled reaction rates. For the near-equilibrium reaction, the ability to correctly capture the heterogeneity in the saturation state remains critical. Inclusion of a Nernst-Planck term to ensure neutral ionic currents under differential diffusion resulted in at most a 9% correction in upscaled rates.

  9. Conditions of contract for construction for building and engineering works designed by the employer : general conditions : guidance for the preparation of particular conditions forms of letter of tender, contract agreement and dispute adjudication agreement

    CERN Document Server

    1999-01-01

    Conditions of Contract for Construction, which are recommended for building or engineering works designed by the Employer or by his representative, the Engineer. Under the usual arrangements for this type of contract, the Contractor constructs the works in accordance with a design provided by the Employer. However, the works may include some elements of Contractor-designed civil, mechanical, electrical and/or construction works.

  10. Synthesis of nano-sized hydroxyapatite powders through solution combustion route under different reaction conditions

    International Nuclear Information System (INIS)

    Ghosh, Samir Kumar; Roy, Sujit Kumar; Kundu, Biswanath; Datta, Someswar; Basu, Debabrata

    2011-01-01

    Calcium hydroxyapatite, Ca 10 (PO 4 ) 6 (OH) 2 (HAp) was synthesized by combustion in the aqueous system containing calcium nitrate-diammonium hydrogen orthophosphate with urea and glycine as fuels. These ceramics are important materials for biomedical applications. Thermo-gravimetric and differential thermal analysis were employed to understand the nature of synthesis process during combustion. Effects of different process parameters namely, nature of fuel (urea and glycine), fuel to oxidizer ratio (0.6-4.0) and initial furnace temperature (300-700 o C) on the combustion behavior as well as physical properties of as-formed powders were investigated. A series of combustion reactions were carried out to optimize the reaction parameters for synthesis of nano-sized HAp powders. The combustion temperature (T f ) for the oxidant and fuels were calculated to be 896 deg. C and 1035 deg. C for the stoichiometric system of urea and glycine respectively. The stoichiometric glycine-calcium nitrate produced higher flame temperature (both calculated and measured) and powder with lower specific surface area (8.75 m 2 /g) compared to the stoichiometric urea-calcium nitrate system (10.50 m 2 /g). Fuel excess combustion in both glycine and urea produced powders with higher surface area. Nanocrystalline HAp powder could be synthesized in situ with a large span of fuel to oxidizer ratio (φ) in case of urea system (0.8 < φ < 4) and (0.6 < φ < 1.5) for the glycine system. Calcium hydroxyapatite particles having diameters ranging between 20 nm and 120 nm could be successfully synthesized through optimized process variable.

  11. Evaluation of the Optimal Reaction Conditions for the Methanolysis and Ethanolysis of Castor Oil Catalyzed by Immobilized Enzymes

    DEFF Research Database (Denmark)

    Andrade, Thalles Allan; Al-Kabalawi, Ibrahim; Errico, Massimiliano

    This study aims to compare the efficiency of the transesterification of castor oil with methanol and ethanol as part of the biodiesel production, using immobilized enzyme Lipozyme IM as catalyst. Different reaction conditions were evaluated and optimized, including the reaction temperature, alcohol...

  12. The association between perceived discriminations and well-being in Korean employed workers: the 4th Korean working conditions survey.

    Science.gov (United States)

    Lee, Hee Sung; Kim, Guang Hwi; Jung, Sung Won; Lee, June-Hee; Lee, Kyung-Jae; Kim, Joo Ja

    2017-01-01

    Around the globe, discrimination has emerged as a social issue requiring serious consideration. From the perspective of public health, the impact of discrimination on the health of affected individuals is a subject of great importance. On the other hand, subjective well-being is a key indicator of an individual's physical, mental, and social health. The present study aims to analyze the relationship between Korean employed workers' subjective health and their exposure to perceived discrimination. The Fourth Korean Working Conditions Survey (KWCS, 2014) was conducted on a representative sample of the economically active population aged 15 years or older, who were either employees or self-employed at the time of interview. After removing inconsistent data, 32,984 employed workers were examined in this study. The data included general and occupational characteristics, perceived discrimination, and well-being. Well-being was measured through the WHO-Five index (1998 version). Multiple logistic regression analysis was used to examine the association between perceived discrimination and well-being. As a group, employed workers who were exposed to discrimination had a significantly higher likelihood of "poor well-being" than their counterparts who were not exposed to discrimination. More specifically, the workers exposed to age discrimination had an odds ratio(OR) of 1.51 (95% CI: 1.36-1.68), workers exposed to discrimination based on educational attainment had an OR of 1.43 (95% CI: 1.26-1.61), and workers exposed to discrimination based on employment type had an OR of 1.68 (95% CI: 1.48-1.91) with respect to poor well-being. Furthermore, workers exposed to a greater number of discriminatory incidents were also at a higher risk of "poor well-being" than their counterparts who were exposed to fewer such incidents. More specifically, the workers with three exposures to discrimination had an OR of 2.60 (95% CI: 1.92-3.53), the workers with two such exposures had an OR of 1

  13. Employment-related difficulties and distressed living condition in patients with hepatitis B virus: A qualitative and quantitative study.

    Science.gov (United States)

    Oka, Taeko; Enoki, Hiroaki; Tokimoto, Yukari; Kawanishi, Teruaki; Minami, Meguru; Okuizumi, Takahiro; Katahira, Kiyohiko

    2017-06-12

    In Japan, an estimated 400,000 people have the hepatitis B virus (HBV), many of whom were infected as a result of group vaccinations. People with HBV face many challenges, including disease progression, employment-related difficulties, and increased medical expenses. The relationship between HBV victims' daily life suffering and poverty associated with HBV-related employment changes has not been examined. We aimed to clarify the employment-related hardships experienced by Japanese HBV victims, and the relationships between these hardships and daily life suffering, including poverty, through qualitative and quantitative analyses. The study population comprised 11,046 people infected with HBV via group vaccination who filed lawsuits in Japan's District Courts by 2014. First, we conducted a qualitative study (2013) using the KJ method, with 107 participants (68 men, mean age 58.9 years; 39 women, mean age 55.3 years). Semi-structured interviews were conducted covering participants' current condition, treatment, medical expenses, and life difficulties (employment- and family-related problems). In 2014, we conducted a quantitative study. We mailed questionnaires to the entire study population, investigating the topics covered in the interviews (response rate 60.1%). Daily life suffering was determined by responses to the question "What do you think about your everyday life situation?" We performed binomial logistic regression analyses to verify the relationships between daily life suffering and disease, employment, and income status. Interview data were integrated into seven islands: intention to work, lack of understanding of HBV in the workplace, inability to buy life insurance, burden due to medical expenses, life failure, dissatisfaction with the system, and wishing for life balance. The quantitative analyses showed significant positive correlations between daily life suffering and liver cancer (odds ratio [OR] 1.47, 95% confidence interval [CI]: 1.00-2.17, p

  14. Development of a reaction cell for in-situ/operando studies of surface of a catalyst under a reaction condition and during catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Luan; Tao, Franklin, E-mail: franklin.tao.2011@gmail.com [Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Department of Chemical and Petroleum Engineering, University of Kansas, Lawrence, Kansas 66045 (United States)

    2016-06-15

    Tracking surface chemistry of a catalyst during catalysis is significant for fundamental understanding of catalytic performance of the catalyst since it allows for establishing an intrinsic correlation between surface chemistry of a catalyst at its working status and its corresponding catalytic performance. Ambient pressure X-ray photoelectron spectroscopy can be used for in-situ studies of surfaces of different materials or devices in a gas. To simulate the gaseous environment of a catalyst in a fixed-bed a flowing gaseous environment of reactants around the catalyst is necessary. Here, we report the development of a new flowing reaction cell for simulating in-situ study of a catalyst surface under a reaction condition in gas of one reactant or during catalysis in a mixture of reactants of a catalytic reaction. The homemade reaction cell is installed in a high vacuum (HV) or ultrahigh vacuum (UHV) environment of a chamber. The flowing gas in the reaction cell is separated from the HV or UHV environment through well sealings at three interfaces between the reaction cell and X-ray window, sample door and aperture of front cone of an energy analyzer. Catalyst in the cell is heated through infrared laser beam introduced through a fiber optics interfaced with the reaction cell through a homemade feedthrough. The highly localized heating on the sample holder and Au-passivated internal surface of the reaction cell effectively minimizes any unwanted reactions potentially catalyzed by the reaction cell. The incorporated laser heating allows a fast heating and a high thermal stability of the sample at a high temperature. With this cell, a catalyst at 800 °C in a flowing gas can be tracked readily.

  15. Development of a reaction cell for in-situ/operando studies of surface of a catalyst under a reaction condition and during catalysis

    International Nuclear Information System (INIS)

    Nguyen, Luan; Tao, Franklin

    2016-01-01

    Tracking surface chemistry of a catalyst during catalysis is significant for fundamental understanding of catalytic performance of the catalyst since it allows for establishing an intrinsic correlation between surface chemistry of a catalyst at its working status and its corresponding catalytic performance. Ambient pressure X-ray photoelectron spectroscopy can be used for in-situ studies of surfaces of different materials or devices in a gas. To simulate the gaseous environment of a catalyst in a fixed-bed a flowing gaseous environment of reactants around the catalyst is necessary. Here, we report the development of a new flowing reaction cell for simulating in-situ study of a catalyst surface under a reaction condition in gas of one reactant or during catalysis in a mixture of reactants of a catalytic reaction. The homemade reaction cell is installed in a high vacuum (HV) or ultrahigh vacuum (UHV) environment of a chamber. The flowing gas in the reaction cell is separated from the HV or UHV environment through well sealings at three interfaces between the reaction cell and X-ray window, sample door and aperture of front cone of an energy analyzer. Catalyst in the cell is heated through infrared laser beam introduced through a fiber optics interfaced with the reaction cell through a homemade feedthrough. The highly localized heating on the sample holder and Au-passivated internal surface of the reaction cell effectively minimizes any unwanted reactions potentially catalyzed by the reaction cell. The incorporated laser heating allows a fast heating and a high thermal stability of the sample at a high temperature. With this cell, a catalyst at 800 °C in a flowing gas can be tracked readily.

  16. Chemoselective O-acylation of hydroxyamino acids and amino alcohols under acidic reaction conditions: History, scope and applications

    Directory of Open Access Journals (Sweden)

    Tor E. Kristensen

    2015-04-01

    Full Text Available Amino acids, whether natural, semisynthetic or synthetic, are among the most important and useful chiral building blocks available for organic chemical synthesis. In principle, they can function as inexpensive, chiral and densely functionalized starting materials. On the other hand, the use of amino acid starting materials routinely necessitates protective group chemistry, and in reality, large-scale preparations of even the simplest side-chain derivatives of many amino acids often become annoyingly strenuous due to the necessity of employing protecting groups, on one or more of the amino acid functionalities, during the synthetic sequence. However, in the case of hydroxyamino acids such as hydroxyproline, serine, threonine, tyrosine and 3,4-dihydroxyphenylalanine (DOPA, many O-acyl side-chain derivatives are directly accessible via a particularly expedient and scalable method not commonly applied until recently. Direct acylation of unprotected hydroxyamino acids with acyl halides or carboxylic anhydrides under appropriately acidic reaction conditions renders possible chemoselective O-acylation, furnishing the corresponding side-chain esters directly, on multigram-scale, in a single step, and without chromatographic purification. Assuming a certain degree of stability under acidic reaction conditions, the method is also applicable for a number of related compounds, such as various amino alcohols and the thiol-functional amino acid cysteine. While the basic methodology underlying this approach has been known for decades, it has evolved through recent developments connected to amino acid-derived chiral organocatalysts to become a more widely recognized procedure for large-scale preparation of many useful side-chain derivatives of hydroxyamino acids and related compounds. Such derivatives are useful in peptide chemistry and drug development, as amino acid amphiphiles for asymmetric catalysis, and as amino acid acrylic precursors for preparation of

  17. Chemoselective O-acylation of hydroxyamino acids and amino alcohols under acidic reaction conditions: History, scope and applications

    Science.gov (United States)

    2015-01-01

    Summary Amino acids, whether natural, semisynthetic or synthetic, are among the most important and useful chiral building blocks available for organic chemical synthesis. In principle, they can function as inexpensive, chiral and densely functionalized starting materials. On the other hand, the use of amino acid starting materials routinely necessitates protective group chemistry, and in reality, large-scale preparations of even the simplest side-chain derivatives of many amino acids often become annoyingly strenuous due to the necessity of employing protecting groups, on one or more of the amino acid functionalities, during the synthetic sequence. However, in the case of hydroxyamino acids such as hydroxyproline, serine, threonine, tyrosine and 3,4-dihydroxyphenylalanine (DOPA), many O-acyl side-chain derivatives are directly accessible via a particularly expedient and scalable method not commonly applied until recently. Direct acylation of unprotected hydroxyamino acids with acyl halides or carboxylic anhydrides under appropriately acidic reaction conditions renders possible chemoselective O-acylation, furnishing the corresponding side-chain esters directly, on multigram-scale, in a single step, and without chromatographic purification. Assuming a certain degree of stability under acidic reaction conditions, the method is also applicable for a number of related compounds, such as various amino alcohols and the thiol-functional amino acid cysteine. While the basic methodology underlying this approach has been known for decades, it has evolved through recent developments connected to amino acid-derived chiral organocatalysts to become a more widely recognized procedure for large-scale preparation of many useful side-chain derivatives of hydroxyamino acids and related compounds. Such derivatives are useful in peptide chemistry and drug development, as amino acid amphiphiles for asymmetric catalysis, and as amino acid acrylic precursors for preparation of

  18. Reaction paths and rate constants of the reaction of hydroxyl radicals with environmental species under tropospheric conditions

    International Nuclear Information System (INIS)

    Leonard, C.; Wahner, A.; Zetzsch, C.

    1987-01-01

    The uv-laser absorption technique in a multipath cell (with excimer-laser photolysis for radical production) is used to investigate the rate constants of the reaction of OH with carbon monoxide. The pressure dependence and the influence of collision partners (measurements in pure oxygen up to one atmosphere) of this important atmospheric chemical reaction are determined. In the kinetic measurements detection limits of 10 7 OH cm -3 are reached with millisecond time resolution. Furthermore the application of the cw-Laser for stationary OH measurements (for example in smog chambers or the free troposphere) is described. The possibilities and limits of different detection methods are discussed with respect to of noise spectra. Modifications of the apparatus with a frequency modulation technique are presented, with an extrapolated detection limit of 10 5 OH cm -3 . (orig.) With 43 refs., 16 figs [de

  19. Effect of Reaction Conditions on the Surface Modification of Cellulose Nanofibrils with Aminopropyl Triethoxysilane

    Directory of Open Access Journals (Sweden)

    Eduardo Robles

    2018-04-01

    Full Text Available Nine different surface modifications of cellulose nanofibrils (CNF with 3-aminopropyl triethoxysilane (ATS by using three different solvent systems (water, ethanol, and a mixture of both were investigated. The effect of reaction conditions, such as silane to cellulose ratio and solvent type were evaluated to determine their contribution to the extent of the silane modification. Nanofibril properties were evaluated by infrared spectroscopy, powder X-ray diffraction, surface free energy, thermogravimetry, 13C and 29Si nuclear magnetic resonance, and electronic microscopy. The influence of the solvent in the solvolysis of the silane was reflected in the presence or absence of ethoxy groups in the silane. On the other hand, whereas the surface modification was increased directly proportionally to silane ratio on the reaction, the aggregation of nanofibrils was also increased, which can play a negative role in certain applications. The increment of silane modification also had substantial repercussions on the crystallinity of the nanofibrils by the addition of amorphous components to the crystalline unit; moreover, silane surface modifications enhanced the hydrophobic character of the nanofibrils.

  20. Comparing Young and Elderly Serial Reaction Time Task Performance on Repeated and Random Conditions

    Directory of Open Access Journals (Sweden)

    Fatemeh Ehsani

    2012-07-01

    Full Text Available Objectives: Acquisition motor skill training in elderly is at great importance. The main purpose of this study was to compare young and elderly performance in serial reaction time task on different repeated and random conditions. Methods & Materials: A serial reaction time task by using software was applied for studying motor learning in 30 young and 30 elderly. Each group divided randomly implicitly and explicitly into subgroups. A task 4 squares with different colors appeared on the monitor and subjects were asked to press its defined key immediately after observing it. Subjects practiced 8 motor blocks (4 repeated blocks, then 2 random blocks and 2 repeated blocks. Block time that was dependent variable measured and Independent-samples t- test with repeated ANOVA measures were used in this test. Results: young groups performed both repeated and random sequences significantly faster than elderly (P0.05. Explicit older subgroup performed 7,8 blocks slower than 6 block with a significant difference (P<0.05. Conclusion: Young adults discriminate high level performance than elderly in both repeated and random practice. Elderly performed random practice better than repeated practice.

  1. Work Values, Cognitive Strategies, and Applicant Reactions in a Structured Pre-Employment Interview for Ethical Integrity.

    Science.gov (United States)

    Pawlowski, Donna R.; Hollwitz, John

    2000-01-01

    Notes that companies emphasize ethical behavior, and schools and professional groups devote many resources to applied ethics training. Describes initial construct validation of a structured ethical integrity pre-employment interview. Reviews evidence relating to cognitive and impression management strategies used when college students encounter an…

  2. Controlled release of volatiles under mild reaction conditions: from nature to everyday products.

    Science.gov (United States)

    Herrmann, Andreas

    2007-01-01

    Volatile organic compounds serve in nature as semiochemicals for communication between species, and are often used as flavors and fragrances in our everyday life. The quite limited longevity of olfactive perception has led to the development of pro-perfumes or pro-fragrances--ideally nonvolatile and odorless fragrance precursors which release the active volatiles by bond cleavage. Only a limited amount of reaction conditions, such as hydrolysis, temperature changes, as well as the action of light, oxygen, enzymes, or microorganisms, can be used to liberate the many different chemical functionalities. This Review describes the controlled chemical release of fragrances and discusses additional challenges such as precursor stability during product storage as well as some aspects concerning toxicity and biodegradability. As the same systems can be applied in different areas of research, the scope of this Review covers fragrance delivery as well as the controlled release of volatiles in general.

  3. [Delayed reactions of active avoidance in white rats under conditions of an alternative choice].

    Science.gov (United States)

    Ioseliani, T K; Sikharulidze, N I; Kadagishvili, A Ia; Mitashvili, E G

    1995-01-01

    It was shown that if the rats had been learned and then tested using conventional pain punishment of erroneous choice they were able to solve the problem of alternative choice only in the period of immediate action of conditioned stimuli. If the pain punishment for erroneously chosen compartment had not been applied in animal learning and testing, rats successfully solved the problem of alternative choice even after 5-second delay. Introduction of pain punishment led to the frustration of earlier elaborated delayed avoidance reactions. Analysis of the obtained results allows us to argue that the apparent incapability of white rats for solving the problems of delayed avoidance is caused by simultaneous action of two different mechanisms, i.e., those of the active and passive avoidance rather than short-term memory deficit.

  4. Effect of reaction conditions on methyl red degradation mediated by boron and nitrogen doped TiO2

    International Nuclear Information System (INIS)

    Galenda, A.; Crociani, L.; Habra, N. El; Favaro, M.; Natile, M.M.; Rossetto, G.

    2014-01-01

    Highlights: • Boron and/or nitrogen-doped TiO 2 for photocatalytic wastewater treatment. • Methyl red degradation/mineralisation as a function of pH, acids and dopants. • Adsorption time influence on photocatalytic process. • Recovery of worn-out catalyst. - Abstract: Nowadays the employment of renewable and sustainable energy sources, and solar light as main option, becomes an urgent need. Photocatalytic processes received great attention in wastewater treatment due to their cheapness, environmental compatibility and optimal performances. Despite the general low selectivity of the photocatalysts, an accurate optimisation of the operational parameters needs to be carried out in order to maximise the process yield. Because of this reason, the present contribution aims to deepen either the knowledge in boron and/or nitrogen doped TiO 2 -based systems and their employment in methyl red removal from aqueous solutions. The samples were obtained by coprecipitation and characterised by XRD, SEM, BET specific surface area, UV–vis and XPS techniques. The catalytic activity was for the first time carefully evaluated with respect to methyl red photodegradation in different conditions as a function of working pH, counter-ions and pre-adsorption time. An ad-hoc study was performed on the importance of the pre-adsorption of the dye, suggesting that an extended adsorption is useless for the catalyst photoactivity, while a partial coverage is preferable. The photocatalytic tests demonstrate the positive influence of boron doping in photo-activated reactions and the great importance of the operational parameters with respect to the simple methyl red bleaching rather than the overall pollutant mineralisation. It is proved, indeed, that different working pH, acidifying means and substrate pre-adsorption time can enhance or limit the catalyst performances with respect to the complete pollutant degradation rather than its partial breakage

  5. “WORKPLACES FOR ALL” A PILOT STUDY ON EMPLOYMENT AND WORKING CONDITIONS FOR PEOPLE WITH DISABILITIES IN MACEDONIA

    Directory of Open Access Journals (Sweden)

    Zora JACHOVA

    2006-12-01

    Full Text Available This article is based on the pilot study "Workplaces for All" conducted in Macedonia in 2006. Another article by Prof. Risto Petrov, based on a part of the same study was published in Journal of Special Education and Rehabilitation January-June No. 1-2, Skopje, 2006; 1-123.The study was a qualitative research project con­ducted in co-operation between Macedonian and Norwegian scientists and representatives from a Macedonian disabled people's organisation (DPO. The main objective was to get research based knowledge about working conditions among people with disabilities in Macedonia in order to prepare for further research, and to raise awareness about the importance of joining forces to improve the rights and working conditions for people with dis­abilities.The pilot study included qualitative interviews of employers and employees at seven protective com­panies. The study has shown the advantage of hav­ing partners from different organisations working together in a research project. The findings do not unveil any irregularities or mistreatment of this quite vulnerable group of employees.The pilot study has produced research based docu­mentation about employment and working condi­tions among people with disabilities in Macedonia. Even though the study found the conditions quite positive, it unveiled several challenges that should be looked deeper into. Among these are the use of assistive technology and adaptations, the social in­clusion both in the company and in the local society and the regulations and process of receiving bene­fits by the protective companies.

  6. A more robust model of the biodiesel reaction, allowing identification of process conditions for significantly enhanced rate and water tolerance.

    Science.gov (United States)

    Eze, Valentine C; Phan, Anh N; Harvey, Adam P

    2014-03-01

    A more robust kinetic model of base-catalysed transesterification than the conventional reaction scheme has been developed. All the relevant reactions in the base-catalysed transesterification of rapeseed oil (RSO) to fatty acid methyl ester (FAME) were investigated experimentally, and validated numerically in a model implemented using MATLAB. It was found that including the saponification of RSO and FAME side reactions and hydroxide-methoxide equilibrium data explained various effects that are not captured by simpler conventional models. Both the experiment and modelling showed that the "biodiesel reaction" can reach the desired level of conversion (>95%) in less than 2min. Given the right set of conditions, the transesterification can reach over 95% conversion, before the saponification losses become significant. This means that the reaction must be performed in a reactor exhibiting good mixing and good control of residence time, and the reaction mixture must be quenched rapidly as it leaves the reactor. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Fast Curing Bio-Based Phenolic Resins via Lignin Demethylated under Mild Reaction Condition

    Directory of Open Access Journals (Sweden)

    Jiongjiong Li

    2017-09-01

    Full Text Available Demethylation technique has been used to enhance lignin reactivity for preparation of phenolic resins. However, the demethylation efficiency and the demethylated lignin (DL reactivity were still unsatisfactory. To improve the demethylation efficiency, alkali lignin was demethylated under different mild conditions using sodium sulfite as a catalyst. Lignin and DL were characterized by 1H-NMR (nuclear magnetic resonance and Fourier transform infrared (FT-IR spectroscopy to determine the demethylation mechanism. With the demethylation of lignin, the methoxyl group content decreased from 1.93 m mol/g to 1.09 m mol/g, and the phenolic hydroxyl group content increased from 0.56 m mol/g to 0.82 m mol/g. These results revealed that methoxyl groups were attacked by SO32−, and some methoxyl groups were converted to phenolic hydroxyl groups by a nucleophilic substitution reaction, generating DL with high reactivity. The chemical properties of lignin-based phenolic resins were studied by 13C-NMR and FT-IR spectroscopy, and their physical properties were also investigated. The results indicated that lignin-based phenolic resins exhibited faster curing rate and shorter gel time. In addition, the bonding strength increased from 0.92 MPa to 1.07 MPa, and the formaldehyde emission decreased from 0.58 mg/L to 0.22 mg/L after lignin demethylated at the optimum condition.

  8. Probing adsorption phenomena on a single crystal Pt-alloy surface under oxygen reduction reaction conditions

    DEFF Research Database (Denmark)

    Bondarenko, Alexander S.; Stephens, Ifan E.L.; Bech, Lone

    2012-01-01

    The adsorption dynamics of *OH and *O species at Pt(111) and Cu/Pt(111) near-surface alloy (NSA) surfaces in oxygen-free and O2-saturated 0.1M HClO4 was investigated. Subsurface Cu modifies the electronic structure at the Pt(111) surface resulting in weaker bonding to adsorbates like *OH, *H or *O....... This provides a basis for the high oxygen reduction activity of the NSA, as predicted by density functional theory calculations. The shift in *OH adsorption of around 0.16V towards more positive potentials can be clearly monitored in absence of O2 and under the oxygen reduction reaction (ORR) conditions...... for the Cu/Pt(111) NSA. In both cases, for Pt(111) and NSA, the *OH(*O) adsorption dynamics is very similar in the absence of oxygen and under ORR conditions. Therefore, theoretical assumptions about the coverage of adsorbates in the absence of oxygen can be reasonably extrapolated to the situation when...

  9. Reaction of genotypes of lulo (Solanum quitoense Lam. to Meloidogyne spp. under field conditions

    Directory of Open Access Journals (Sweden)

    Claudia Salazar-González

    2017-05-01

    Full Text Available In Colombia, root-knot nematodes Meloidog yne spp. are considered as one of the main constraints in lulo crop production . These nematodes can cause root damage resulting in low production. The aim of this study was to evaluate under field conditions the reaction of 16 genotypes of lulo, Solanum quitoense Lam. (Solanaceae, of the Castilla variety and the species S. hirtum Vahl., previously selected in a greenhouse experiment and categorized as moderately resistant and resistant to the attack by Meloidog yne sp. A chemical treatment and a control treatment, the latter based on the most susceptible genotype in greenhouse experiments were also included. The experiment was conducted in a lulo grove naturally infested with root-knot nematodes under a randomized complete block design with three replications and nine plants per experimental unit. The response variables were incidence, severity and yield. The incidence was higher than 80 % in all cases, but the severity varied because of their genetic condition; BR03 and BR01 being genotypes with lower rates of severity, with values of 1.0 % and 0.8 %, respectively. The yield analysis of variance showed significant differences, indicating that genotypes SQBR01 and SQLF04, reached the highest values with 4.77 and 4.74 t/ha in a total of three harvests.

  10. Simplified models of transport and reactions in conditions of CO2 storage in saline aquifers

    Science.gov (United States)

    Suchodolska, Katarzyna; Labus, Krzysztof

    2016-04-01

    Simple hydrogeochemical models may serve as tools of preliminary assessment of CO2 injection and sequestraton impact on the aquifer and cap-rocks. In order to create models of reaction and transport in conditions of CO2 injection and storage, the TOUGHREACT simulator, and the Geochemist's Workbench software were applied. The chemical composition of waters for kinetic transport models based on the water - rock equilibrium calculations. Analyses of reaction and transport of substances during CO2 injection and storage period were carried out in three scenarios: one-dimensional radial model, and two-dimensional model of CO2 injection and sequestration, and one-dimensional model of aquifer - cap-rock interface. Modeling was performed in two stages. The first one simulated the immediate changes in the aquifer and insulating rocks impacted by CO2 injection (100 days in case of reaction model and 30 years in transport and reaction model), the second - enabled assessment of long-term effects of sequestration (20000 years). Reactions' quality and progress were monitored and their effects on formation porosity and sequestration capacity in form of mineral, residual and free phase of CO2 were calculated. Calibration of numerical models (including precipitation of secondary minerals, and correction of kinetics parameters) describing the initial stage of injection, was based on the experimental results. Modeling allowed to evaluate the pore space saturation with gas, changes in the composition and pH of pore waters, relationships between porosity and permeability changes and crystallization or dissolution minerals. We assessed the temporal and spatial extent of crystallization processes, and the amount of carbonates trapping. CO2 in mineral form. The calculated sequestration capacity of analyzed formations reached n·100 kg/m3 for the: dissolved phase - CO(aq), gas phase - CO2(g) and mineral phase, but as much as 101 kg/m3 for the supercritical phase - SCCO2. Processes of gas

  11. Global exponential stability and periodicity of reaction-diffusion delayed recurrent neural networks with Dirichlet boundary conditions

    International Nuclear Information System (INIS)

    Lu Junguo

    2008-01-01

    In this paper, the global exponential stability and periodicity for a class of reaction-diffusion delayed recurrent neural networks with Dirichlet boundary conditions are addressed by constructing suitable Lyapunov functionals and utilizing some inequality techniques. We first prove global exponential converge to 0 of the difference between any two solutions of the original reaction-diffusion delayed recurrent neural networks with Dirichlet boundary conditions, the existence and uniqueness of equilibrium is the direct results of this procedure. This approach is different from the usually used one where the existence, uniqueness of equilibrium and stability are proved in two separate steps. Furthermore, we prove periodicity of the reaction-diffusion delayed recurrent neural networks with Dirichlet boundary conditions. Sufficient conditions ensuring the global exponential stability and the existence of periodic oscillatory solutions for the reaction-diffusion delayed recurrent neural networks with Dirichlet boundary conditions are given. These conditions are easy to check and have important leading significance in the design and application of reaction-diffusion recurrent neural networks with delays. Finally, two numerical examples are given to show the effectiveness of the obtained results

  12. N,N-Diethyl-1-Tosyl-3-Indoleglyoxylamide as a Dienophile in Diels-Alder Reactions. Hyperbaric vs. Thermal Conditions

    Directory of Open Access Journals (Sweden)

    B. Biolatto

    2000-03-01

    Full Text Available Under high pressure conditions, the Diels-Alder reaction involving N,N-diethyl-1-tosyl-3-indoleglyoxylamide and 1-(N-acetyl-N-propylamino-1,3-butadiene produces a highly functionalized intermediate for the synthesis of Indole Alkaloids, in shorter times and higher yields than under thermal conditions.

  13. Altered vocal fold kinematics in synthetic self-oscillating models that employ adipose tissue as a lateral boundary condition.

    Science.gov (United States)

    Saidi, Hiba; Erath, Byron D.

    2015-11-01

    The vocal folds play a major role in human communication by initiating voiced sound production. During voiced speech, the vocal folds are set into sustained vibrations. Synthetic self-oscillating vocal fold models are regularly employed to gain insight into flow-structure interactions governing the phonation process. Commonly, a fixed boundary condition is applied to the lateral, anterior, and posterior sides of the synthetic vocal fold models. However, physiological observations reveal the presence of adipose tissue on the lateral surface between the thyroid cartilage and the vocal folds. The goal of this study is to investigate the influence of including this substrate layer of adipose tissue on the dynamics of phonation. For a more realistic representation of the human vocal folds, synthetic multi-layer vocal fold models have been fabricated and tested while including a soft lateral layer representative of adipose tissue. Phonation parameters have been collected and are compared to those of the standard vocal fold models. Results show that vocal fold kinematics are affected by adding the adipose tissue layer as a new boundary condition.

  14. Probing adsorption phenomena on a single crystal Pt-alloy surface under oxygen reduction reaction conditions

    International Nuclear Information System (INIS)

    Bondarenko, Alexander S.; Stephens, Ifan E.L.; Bech, Lone; Chorkendorff, Ib

    2012-01-01

    Highlights: ► Impedance spectroscopy of Cu/Pt(1 1 1) near-surface alloy and Pt(1 1 1). ► Presence of oxygen changes little the adsorption dynamics. ► Adsorption dynamics similar on alloy and Pt(1 1 1). ► Electrosorption phenomena on alloy shifted in potential, relative to Pt(1 1 1). - Abstract: The adsorption dynamics of *OH and *O species at Pt(1 1 1) and Cu/Pt(1 1 1) near-surface alloy (NSA) surfaces in oxygen-free and O 2 -saturated 0.1 M HClO 4 was investigated. Subsurface Cu modifies the electronic structure at the Pt(1 1 1) surface resulting in weaker bonding to adsorbates like *OH, *H or *O. This provides a basis for the high oxygen reduction activity of the NSA, as predicted by density functional theory calculations. The shift in *OH adsorption of around 0.16 V towards more positive potentials can be clearly monitored in absence of O 2 and under the oxygen reduction reaction (ORR) conditions for the Cu/Pt(1 1 1) NSA. In both cases, for Pt(1 1 1) and NSA, the *OH(*O) adsorption dynamics is very similar in the absence of oxygen and under ORR conditions. Therefore, theoretical assumptions about the coverage of adsorbates in the absence of oxygen can be reasonably extrapolated to the situation when oxygen reduction takes place at the surface. A ∼5-fold improvement in the ORR activity over the Pt(1 1 1) at 0.9 V (RHE) was measured for the Cu/Pt(1 1 1) near-surface alloy.

  15. A field ion microscope study of the surface reaction of tungsten with n-octanol under an applied positive voltage: reaction conditions for the 'splitting' of (110) plane

    International Nuclear Information System (INIS)

    Terao, T.; Iwatsu, F.; Morikawa, H.

    1993-01-01

    Field ion microscopy is a powerful tool for the study of surface phenomena on an atomic scale, especially when they are crystal plane dependent, because the microscope shows many crystal planes of the sample tip simultaneously. Although a large number of FIM studies on vapor deposition, surface diffusion and surface reactions at a metal-gas interface have been reported, those on reactions at a metal-liquid interface are few. The authors have studied the corrosion or tungsten with aqueous solutions and found that water corroded the tungsten tips very severely to reduce the radius of curvature of the tip cap drastically. The reaction was so severe that it was not possible to trace it back to the very initial stages. They adopted, as a weaker reagent, one of the higher alcohols, n-octanol(C 8 H 17 OH), and found that it reacted with tungsten tips when an electrical pulse with a positive voltage between 5 and 10V was applied to the tip, giving very interesting field ion images in which the central (110) plane was divided into two parts located side by side across the [001] zone line. This means that some anisotropic surface reaction occurred which made a groove along the [001] zone line going through the (110) plane, usually the most stable plane chemically for bcc metals. They named this phenomenon 'splitting'. This reaction was less severe than that with water and some results on the morphology of the groove and on the reaction sequence have been reported. In the present paper more detailed reaction conditions which give rise to the splitting are described

  16. Attrition of limestones by impact loading in fluidized beds: The influence of reaction conditions

    Energy Technology Data Exchange (ETDEWEB)

    Scala, Fabrizio [Istituto di Ricerche sulla Combustione, Consiglio Nazionale delle Ricerche, Napoli (Italy); Salatino, Piero [Istituto di Ricerche sulla Combustione, Consiglio Nazionale delle Ricerche, Napoli (Italy); Dipartimento di Ingegneria Chimica, Universita degli Studi di Napoli Federico II, Napoli (Italy)

    2010-09-15

    The extent of attrition associated with impact loading was studied for five different limestones pre-processed in fluidized bed under different reaction conditions. The experimental procedure was based on the measurement of the amount and the particle size distribution of the debris generated upon impact of sorbent samples against a target at velocities between 10 and 45 m/s. The effect of calcination, sulfation and calcination/re-carbonation on impact damage was assessed. Fragmentation by impact loading of the limestones was significant and increased with the impact velocity. Lime samples displayed the largest propensity to undergo impact damage, followed by sulfated, re-carbonated and raw limestones. Fragmentation of the sulfated samples followed a pattern typical of the failure of brittle materials. On the other hand, the behaviour of lime samples better conformed to a disintegration failure mode, with extensive generation of very fine fragments. Raw limestone and re-carbonated lime samples followed either of the two patterns depending on the sorbent nature. The extent of particle fragmentation increased after multiple impacts, but the incremental amount of fragments generated upon one impact decreased with the number of successive impacts. (author)

  17. Dynamic thermal reaction analysis of wall structures in various cooling operation conditions

    International Nuclear Information System (INIS)

    Yan, Biao; Long, Enshen; Meng, Xi

    2015-01-01

    Highlights: • Four different envelop structures are separately built in the same test building. • Cooling temperature and operation time were chosen as perturbations. • State Space Method is used to analyze the influence of wall sequence order. • The numerical models are validated by the comparisons of theory and test results. • The contrast of temperature change of different envelop structures was stark. - Abstract: This paper proposes a methodology of performance assessing of envelops under different cooling operation conditions, by focusing on indoor temperature change and dynamic thermal behavior performance of walls. To obtain a general relationship between the thermal environment change and the reaction of envelop, variously insulated walls made with the same insulation material are separately built in the same wall of a testing building with the four different structures, namely self-heat insulation (full insulation material), exterior insulation, internal insulation and intermediate insulation. The advantage of this setting is that the test targets are exposed to the same environmental variables, and the tests results are thus comparable. The target responses to two types of perturbations, cooling temperature and operation time were chosen as the important variations in the tests. Parameters of cooling set temperature of 22 °C and 18 °C, operation and restoring time 10 min and 15 min are set in the test models, and discussed with simulation results respectively. The results reveal that the exterior insulation and internal insulation are more sensitive to thermal environment change than self-heat insulation and intermediate insulation.

  18. Modeling Time-Dependent Behavior of Concrete Affected by Alkali Silica Reaction in Variable Environmental Conditions.

    Science.gov (United States)

    Alnaggar, Mohammed; Di Luzio, Giovanni; Cusatis, Gianluca

    2017-04-28

    Alkali Silica Reaction (ASR) is known to be a serious problem for concrete worldwide, especially in high humidity and high temperature regions. ASR is a slow process that develops over years to decades and it is influenced by changes in environmental and loading conditions of the structure. The problem becomes even more complicated if one recognizes that other phenomena like creep and shrinkage are coupled with ASR. This results in synergistic mechanisms that can not be easily understood without a comprehensive computational model. In this paper, coupling between creep, shrinkage and ASR is modeled within the Lattice Discrete Particle Model (LDPM) framework. In order to achieve this, a multi-physics formulation is used to compute the evolution of temperature, humidity, cement hydration, and ASR in both space and time, which is then used within physics-based formulations of cracking, creep and shrinkage. The overall model is calibrated and validated on the basis of experimental data available in the literature. Results show that even during free expansions (zero macroscopic stress), a significant degree of coupling exists because ASR induced expansions are relaxed by meso-scale creep driven by self-equilibriated stresses at the meso-scale. This explains and highlights the importance of considering ASR and other time dependent aging and deterioration phenomena at an appropriate length scale in coupled modeling approaches.

  19. Kinetics of Hydrogen Radical Reactions with Toluene Including Chemical Activation Theory Employing System-Specific Quantum RRK Theory Calibrated by Variational Transition State Theory.

    Science.gov (United States)

    Bao, Junwei Lucas; Zheng, Jingjing; Truhlar, Donald G

    2016-03-02

    Pressure-dependent reactions are ubiquitous in combustion and atmospheric chemistry. We employ a new calibration procedure for quantum Rice-Ramsperger-Kassel (QRRK) unimolecular rate theory within a chemical activation mechanism to calculate the pressure-falloff effect of a radical association with an aromatic ring. The new theoretical framework is applied to the reaction of H with toluene, which is a prototypical reaction in the combustion chemistry of aromatic hydrocarbons present in most fuels. Both the hydrogen abstraction reactions and the hydrogen addition reactions are calculated. Our system-specific (SS) QRRK approach is adjusted with SS parameters to agree with multistructural canonical variational transition state theory with multidimensional tunneling (MS-CVT/SCT) at the high-pressure limit. The new method avoids the need for the usual empirical estimations of the QRRK parameters, and it eliminates the need for variational transition state theory calculations as a function of energy, although in this first application we do validate the falloff curves by comparing SS-QRRK results without tunneling to multistructural microcanonical variational transition state theory (MS-μVT) rate constants without tunneling. At low temperatures, the two approaches agree well with each other, but at high temperatures, SS-QRRK tends to overestimate falloff slightly. We also show that the variational effect is important in computing the energy-resolved rate constants. Multiple-structure anharmonicity, torsional-potential anharmonicity, and high-frequency-mode vibrational anharmonicity are all included in the rate computations, and torsional anharmonicity effects on the density of states are investigated. Branching fractions, which are both temperature- and pressure-dependent (and for which only limited data is available from experiment), are predicted as a function of pressure.

  20. Constrained approximation of effective generators for multiscale stochastic reaction networks and application to conditioned path sampling

    Energy Technology Data Exchange (ETDEWEB)

    Cotter, Simon L., E-mail: simon.cotter@manchester.ac.uk

    2016-10-15

    Efficient analysis and simulation of multiscale stochastic systems of chemical kinetics is an ongoing area for research, and is the source of many theoretical and computational challenges. In this paper, we present a significant improvement to the constrained approach, which is a method for computing effective dynamics of slowly changing quantities in these systems, but which does not rely on the quasi-steady-state assumption (QSSA). The QSSA can cause errors in the estimation of effective dynamics for systems where the difference in timescales between the “fast” and “slow” variables is not so pronounced. This new application of the constrained approach allows us to compute the effective generator of the slow variables, without the need for expensive stochastic simulations. This is achieved by finding the null space of the generator of the constrained system. For complex systems where this is not possible, or where the constrained subsystem is itself multiscale, the constrained approach can then be applied iteratively. This results in breaking the problem down into finding the solutions to many small eigenvalue problems, which can be efficiently solved using standard methods. Since this methodology does not rely on the quasi steady-state assumption, the effective dynamics that are approximated are highly accurate, and in the case of systems with only monomolecular reactions, are exact. We will demonstrate this with some numerics, and also use the effective generators to sample paths of the slow variables which are conditioned on their endpoints, a task which would be computationally intractable for the generator of the full system.

  1. Economic and environmental performance of oil transesterification in supercritical methanol at different reaction conditions: Experimental study with a batch reactor

    International Nuclear Information System (INIS)

    Tomic, Milan; Micic, Radoslav; Kiss, Ferenc; Dedovic, Nebojsa; Simikic, Mirko

    2015-01-01

    Highlights: • Influence of reaction parameters on FAME yields has been investigated. • The highest yield (93%) was achieved after 15 min at 350 °C and 12 MPa. • Models which predict with high certainty yields at different reaction conditions. • Economic and environmental performance of supercritical transesterification. • The lowest costs and impacts are always achieved at the highest yields. - Abstract: This study aims to investigate the influence of various reaction parameters (temperatures, working pressures and reaction time) on biodiesel yields and environmental and economic performance of rapeseed oil transesterification in supercritical methanol. Experiments were carried out in a laboratory-scale batch reactor. Results were statistically analysed and multiple regression models which describe and predict biodiesel yields with high certainty at different reaction conditions were provided. The highest biodiesel yield (93 wt%) was achieved at 350 °C and 12 MPa after 15 min of reaction. The lowest direct costs and life cycle environmental impacts (in terms of GHG emissions and fossil energy demand) are achieved at the highest yield due to the lowest oil consumption per unit of biodiesel produced. The results of sensitivity analysis showed that even at significantly lower oil feedstock prices this observation stands firm

  2. Investigating the combined effects of heat and lighting on students reaction time in laboratory condition

    Directory of Open Access Journals (Sweden)

    Zohre Mohebian

    2016-12-01

    Full Text Available Introduction: In many workplaces there is exposure to heat and light simultaneously. This study investigated the combined effect of heat and lighting on some cognitive performance, i.e. reaction time. Methodology: the present semi-experimental study was conducted 2015 on 33 healthy students (16 girls and 17 boys with a mean age of 22.1 in the thermal stress chamber. The reaction time parameter by the reaction time measurement device, after exposure to different heat surfaces (dry temperatures 22 °C and 37 °C and lighting surfaces (200, 500 and 1500 lux. Data were analyzed using ANOVA test in SPSS-20. Results: The results showed that the average simple, diagnostic, two-color selective, two-sound selective reaction times and reaction time error increased after combined exposure to heat and lighting and showed a significant difference (P<0.05. The maximum score of reaction time belong to temperature of 37 c° and lighting of 1500 lux, the minimum score of reaction time belong to temperature of 22 °c and lighting of 1500 lux.

  3. Exploring conditions for the enhancement of acene semiconductors through the use of the Diels-alder reaction

    Science.gov (United States)

    Qualizza, Brittni A.

    This dissertation demonstrates the application of SAMs to the surface of acene crystals, specifically of tetracene and rubrene, using the Diels-Alder reaction. The second chapter details preliminary reaction results and two analytical methods which were employed to confirm adsorption of the dienophile on the surface of single crystals, tetracene and rubrene. These were mass spectrometry and X-ray photoelectron spectroscopy (XPS). Mass spectrometry experiments distinguish the chemical identity of adduct on the crystals and also it discerned chemi- and physisorbed molecules from one another. XPS was used to prove face selectivity of the reaction by the detection of dichloromaleic anhydride. From a mechanistic standpoint, this system demonstrated unusual steric effects: the reaction of one face of the tetracene crystal was virtually inert, while another face was facile. The dienophiles' steric bulk was also expected to play critical role for these confined systems, however analysis of surface data was hindered by the relative lack of corresponding solution kinetic data. While the rate of anthracene's reaction has been studied extensively with a range of dienophiles and tetracene/pentacene has been studied theoretically (with limited experimental reports), an expansive report was generated to aid in future interpretations of acene systems. These kinetic results constitute chapter three.

  4. The reaction between iodine and organic coatings under severe PWR accident conditions. An experimental parameter study

    Energy Technology Data Exchange (ETDEWEB)

    Hellmann, S; Funke, F; Greger, G U; Bleier, A; Morell, W [Siemens AG, Power Generation Group, Erlangen (Germany)

    1996-12-01

    An extensive experimental parameter study was performed on the deposition and on the resuspension kinetics in the reaction system iodine/organically coated surfaces. Both reactions in the gas phase and in the liquid phase were investigated and kinetic rate constants suitable for modelling were derived. Previous experimental studies on the reaction of iodine with organic coated surfaces were mostly limited to temperatures below 100{sup o}C. Thus, this parameter study aims at filling a gap and providing kinetic data on heterogeneous reactions with organic surfaces in the accident-relevant temperature range of 100-160{sup o}C. Two types of laboratory experiments carried out at Siemens/KWU using coatings representative for German power plants (epoxy-tape paint), namely gas phase tests and liquid phase tests. (author) 6 figs., 6 tabs., 5 refs.

  5. Effect of reaction conditions on film morphology of polyaniline composite membranes for gas separation

    KAUST Repository

    Blinova, Natalia V.; Stejskal, Jaroslav; Frechet, Jean; Švec, František

    2012-01-01

    precipitation, dispersion, or emulsion polymerization of aniline with simultaneous deposition on top of the porous polypropylene support, which was immersed in the reaction mixture. Variables such as temperature, concentration of reagents, presence of steric

  6. Initial reaction between CaO and SO2 under carbonating and non-carbonating conditions

    DEFF Research Database (Denmark)

    Rasmussen, Martin Hagsted; Wedel, Stig; Pedersen, Kim H.

    2015-01-01

    The initial kinetics of the CaO/SO2 reaction have been investigated for reaction times shorter than 1s and in the temperature interval between 450 and 600°C under both carbonating and non-carbonating conditions (0-20 vol% CO2) to clarify how recirculating CaO influences the emission of SO2 from...... showed that the CaO conversion with respect to SO2 declined when the CO2 concentration was increased. Under all conditions, larger specific surface areas of CaO gave higher reaction rates with SO2. Higher temperatures had a positive effect on the reaction between SO2 and CaO under non......-carbonating conditions, but no or even a negative effect under carbonating conditions. The results led to the conclusion that SO2 released from raw meal in the upper stages of the preheater does not to any significant extent react with CaO recirculating in the preheater tower....

  7. A variational approach to bifurcation points of a reaction-diffusion system with obstacles and neumann boundary conditions

    Czech Academy of Sciences Publication Activity Database

    Eisner, Jan; Kučera, Milan; Väth, Martin

    2016-01-01

    Roč. 61, č. 1 (2016), s. 1-25 ISSN 0862-7940 R&D Projects: GA ČR GA13-12580S Institutional support: RVO:67985904 ; RVO:67985840 Keywords : reaction-diffusion system * unlateral condition * variational inequality Subject RIV: EG - Zoology; BA - General Mathematics (MU-W) Impact factor: 0.618, year: 2016

  8. Should Student Employment Be Subsidized? Conditional Counterfactuals and the Outcomes of Work-Study Participation. A CAPSEE Working Paper

    Science.gov (United States)

    Scott-Clayton, Judith; Minaya, Veronica

    2014-01-01

    Student employment subsidies are one of the largest types of federal employment subsidies, and one of the oldest forms of student aid. Yet it is unclear whether they help or harm students' long term outcomes. We present a framework that decomposes overall effects into a weighted average of effects for marginal and inframarginal workers. We then…

  9. Evaluation of the Optimal Reaction Conditions for the Methanolysis and Ethanolysis of Castor Oil Catalyzed by Immobilized Enzymes

    DEFF Research Database (Denmark)

    Andrade, Thalles Allan; Al-Kabalawi, Ibrahim F.; Errico, Massimiliano

    :1 methanol-to-oil molar ratio, 5 wt% of enzymes, 7.5 wt% of water, 50 wt% n-hexane, at 50 °C. The fatty acid methyl esters content was 96.8 % and 1.0 % FFA. Regarding the reactions with ethanol, 98.0 % fatty acid ethyl ester was obtained and 1.3 % FFA, when the reaction was carried out at 60 °C, 4:1 ethanol......As an alternative to the use of chemical catalysts, immobilized enzyme Lipozyme 435 was evaluated as catalyst for biodiesel production, comparing its efficiency in the castor oil transesterification with methanol and ethanol. Different reaction conditions were assessed and optimized, including...... the reaction temperature (35 – 60 °C), alcohol-to-oil molar ratio (from 3:1 to 6:1), amount of catalyst (from 3 to 15 wt% by weight of oil), addition of water (0 – 15 wt%), and use of n-hexane as a solvent (0 – 75 wt%). For the transesterification with methanol, the optimal reaction conditions were 3...

  10. The reaction between iodine and silver under severe PWR accident conditions. An experimental parameter study

    Energy Technology Data Exchange (ETDEWEB)

    Funke, F; Greger, G U; Bleier, A; Hellmann, S; Morell, W [Siemens AG, Power Generation Group, Erlangen (Germany)

    1996-12-01

    An extensive experimental parameter study was performed on the kinetics in the reaction system I{sub 2}/Ag and I{sup -}/Ag in a laboratory-scale apparatus.Starting with I{sub 2} or I{sup -} solutions and silver powder suspensions, the decrease of soluted I{sub 2} or I{sup -}, respectively, due to fixation on the silver particles, was monitored as function of time using the radioactive tracer I-131. The measured data were analyzed using a model of first order kinetics with respect to the iodine concentration. However, the analysis using first order kinetics had to be performed separately in an early, fast reaction phase and in a late, slow reaction phase. The reason for this unexpected behaviour was not identified. Thus, rate constant, two for each test, were deduced from 14 I{sub 2}/Ag main tests and from 36 I{sup -}/Ag tests. No dependencies of the rate constants were found on the parameters temperature, initial iodine concentration, presence of boric acid, type of silver educt, and pretreatment of the silver educt prior to the tests. However, the stirring of the reaction solution generally enhanced the kinetics highlighting the importance of mass transfer. The I{sup -}/Ag reaction proceeded only if there was no inertization of the reaction solution by sparging with nitrogen. The temperature-independent rate constant for the early, fast I{sub 2}/Ag reaction phase is 2E-5 m/s. However, a smaller rate constant of 6E-6 m/s is recommended for use in source term calculations with IMPAIR, which already contains a first order model. Analogously, the temperature-independent I{sup -}/Ag reaction rate constant is 8E-6 m/s in an early, fast reaction phase. For use in source term calculations, a smaller rate constant of 2E-6 m/s is recommended. The lower bound of the I{sup -}/Ag rate constant was 3E-8 m/s which could be used in very conservative source term calculations. (author) 20 figs., 6 tabs., 15 refs.

  11. Supervisors' attitudes and skills for active listening with regard to working conditions and psychological stress reactions among subordinate workers.

    Science.gov (United States)

    Mineyama, Sachiko; Tsutsumi, Akizumi; Takao, Soshi; Nishiuchi, Kyoko; Kawakami, Norito

    2007-03-01

    We investigated whether supervisors' listening attitudes and skills were related to working conditions and psychological stress reactions among their subordinates. The subjects included 41 male supervisors and their immediate subordinates (n=203). The supervisors completed a short version of the Active Listening Attitude Scale (ALAS) consisting of two subscales: Listening Attitude and Listening Skill for Active Listening. The subordinates rated working conditions and their psychological stress reactions using selected scales of the Job Content Questionnaire and the Brief Job Stress Questionnaire. Those subordinates who worked under supervisors with a higher score of Listening Attitude and Listening Skill reported a more favorable psychological stress reaction than those who worked under supervisors with a lower score of Listening Attitude and Listening Skill. Those subordinates who worked under supervisors with a higher score of Listening Skill reported higher worksite support than those who worked under supervisors with a lower score of Listening Skill. Those subordinates who worked under supervisors with a higher score of Listening Attitude reported higher job control than those who worked under supervisors with a lower score of Listening Attitude. A supervisor's listening attitude and skill appeared to affect psychological stress reactions predominantly among male subordinates than among female subordinates. Psychological stress reactions were lower among younger subordinates who worked under supervisors with high listening skill, while no statistically difference was observed among older subordinates. These findings suggest that a supervisor's listening attitude and skill have an effect on working conditions and psychological stress reactions among subordinates and that the effects vary according to the subordinates' sex and age.

  12. A contribution to the study of the hydrogen evolution reaction on tungsten under water electrolysis conditions

    International Nuclear Information System (INIS)

    Tanaka, A.A.; Avaca, L.A.; Gonzalez, E.R.

    1984-01-01

    Tungsten, electrodeposited on mild steel from aqueous solutions, has been shown to behave similarly to electroplated nickel when used as a cathode in 28% KOH at 60 0 C and current densities of the order of 135 mA cm -2 . When compared with bare mild steel the tungsten cathodes present an overpotential 50mV higher, but this is largely compensated by the extremely higher chemical stability of the deposits in the electrolyte. This is particularly important when the electrolyzer is going to be used in an intermittent fashion. In the present work, the hydrogen evolution reaction was studied on pure and electrodeposited tungsten electrodes in alkaline solutions through the recording of steady-state polarization curves. By comparison of the experimental electrochemical parameters with those predicted by theory, it was established that the mechanism of the reaction is of the type Volmer-Heyrowsky, with the electrochemical desorption reaction being the rate determining step

  13. Reaction probability derived from an interpolation formula for diffusion processes with an absorptive boundary condition

    International Nuclear Information System (INIS)

    Misawa, T.; Itakura, H.

    1995-01-01

    The present article focuses on a dynamical simulation of molecular motion in liquids. In the simulation involving diffusion-controlled reaction with discrete time steps, lack of information regarding the trajectory within the time step may result in a failure to count the number of reactions of the particles within the step. In order to rectify this, an interpolated diffusion process is used. The process is derived from a stochastic interpolation formula recently developed by the first author [J. Math. Phys. 34, 775 (1993)]. In this method, the probability that reaction has occurred during the time step given the initial and final positions of the particles is calculated. Some numerical examples confirm that the theoretical result corresponds to an improvement over the Clifford-Green work [Mol. Phys. 57, 123 (1986)] on the same matter

  14. Reactions of CF3O radicals with selected alkenes and aromatics under atmospheric conditions

    DEFF Research Database (Denmark)

    Kelly, C.; Sidebottom, H.W.; Treacy, J.

    1994-01-01

    Rate data for the reactions of CF3O radicals with alkenes and aromatic compounds have been determined at 298 K using a relative rate method. The data are analyzed in terms of structure-reactivity relationships, and their importance to the atmospheric chemistry of CF3O discussed.......Rate data for the reactions of CF3O radicals with alkenes and aromatic compounds have been determined at 298 K using a relative rate method. The data are analyzed in terms of structure-reactivity relationships, and their importance to the atmospheric chemistry of CF3O discussed....

  15. Photocatalytic dechlorination of PCB 138 using leuco-methylene blue and visible light; reaction conditions and mechanisms

    International Nuclear Information System (INIS)

    Izadifard, Maryam; Langford, Cooper H.; Achari, Gopal

    2010-01-01

    A study of dechlorination of PCB 138, under visible light employing methylene blue (MB) and triethylamine (TEA) in acetonitrile/water has been conducted to investigate the details of the mechanism of dechlorination and to determine the efficiency of the process for this representative congener. Two other amines, N-methyldiethanolamine (MEDA) and (triethanolamine) TEOA also replaced TEA and two other solvents, methanol and ethanol replacing acetonitrile were examined for effects on reaction rates. The results show that PCB 138 can be dechlorinated efficiently in this photocatalytic reaction. Clarifying ambiguities in several previous reports, the reduced form of MB, leuco-methylene blue (LMB) was identified as responsible for the photoreaction with its excited state transferring an electron to PCBs; oxidized LMB (i.e. MB) is reduced back to LMB by the excess amine present. The reaction depends on a cycle driven by the amine as a sacrificial electron donor. MEDA proved to be the most efficient electron donor; apparently in consequence of the most favourable steady state concentration of LMB. Methanol and ethanol may be used to replace acetonitrile with little change in the efficiency of the reaction.

  16. Heterogeneous Reactions between Toluene and NO2 on Mineral Particles under Simulated Atmospheric Conditions.

    Science.gov (United States)

    Niu, Hejingying; Li, Kezhi; Chu, Biwu; Su, Wenkang; Li, Junhua

    2017-09-05

    Heterogeneous reactions between organic and inorganic gases with aerosols are important for the study of smog occurrence and development. In this study, heterogeneous reactions between toluene and NO 2 with three atmospheric mineral particles in the presence or absence of UV light were investigated. The three mineral particles were SiO 2 , α-Fe 2 O 3 , and BS (butlerite and szmolnokite). In a dark environment, benzaldehyde was produced on α-Fe 2 O 3 . For BS, nitrotoluene and benzaldehyde were obtained. No aromatic products were produced in the absence of NO 2 in the system. In the presence of UV irradiation, benzaldehyde was detected on the SiO 2 surface. Identical products were produced in the presence and absence of UV light over α-Fe 2 O 3 and BS. UV light promoted nitrite to nitrate on mineral particles surface. On the basisi of the X-ray photoelectron spectroscopy (XPS) results, a portion of BS was reduced from Fe 3+ to Fe 2+ with the adsorption of toluene or the reaction with toluene and NO 2 . Sulfate may play a key role in the generation of nitrotoluene on BS particles. From this research, the heterogeneous reactions between organic and inorganic gases with aerosols that occur during smog events will be better understood.

  17. Flow chemistry kinetic studies reveal reaction conditions for ready access to unsymmetrical trehalose analogues.

    Science.gov (United States)

    Patel, Mitul K; Davis, Benjamin G

    2010-10-07

    Monofunctionalization of trehalose, a widely-found symmetric plant disaccharide, was studied in a microreactor to give valuable kinetic insights that have allowed improvements in desymmetrization yields and the development of a reaction sequence for large scale monofunctionalizations that allow access to probes of trehalose's biological function.

  18. Outcome of homogeneous and heterogeneous reactions in Darcy-Forchheimer flow with nonlinear thermal radiation and convective condition

    Science.gov (United States)

    Hayat, T.; Shah, Faisal; Alsaedi, A.; Hussain, Zakir

    The present analysis aims to report the consequences of nonlinear radiation, convective condition and heterogeneous-homogeneous reactions in Darcy-Forchheimer flow over a non-linear stretching sheet with variable thickness. Non-uniform magnetic field and nonuniform heat generation/absorption are accounted. The governing boundary layer partial differential equations are converted into a system of nonlinear ordinary differential equations. The computations are organized and the effects of physical variables such as thickness parameter, power index, Hartman number, inertia and porous parameters, radiation parameter, Biot number, Prandtl number, ratio parameter, heat generation parameter and homogeneous-heterogeneous reaction parameter are investigated. The variations of skin friction coefficient and Nusselt number for different interesting variables are plotted and discussed. It is noticed that Biot number and heat generation variable lead to enhance the temperature distribution. The solutal boundary layer thickness decreases for larger homogeneous variable while reverse trend is seen for heterogeneous reaction.

  19. Rock-fluid chemical interactions at reservoir conditions: The influence of brine chemistry and extent of reaction

    Science.gov (United States)

    Anabaraonye, B. U.; Crawshaw, J.; Trusler, J. P. M.

    2016-12-01

    Following carbon dioxide injection in deep saline aquifers, CO2 dissolves in the formation brines forming acidic solutions that can subsequently react with host reservoir minerals, altering both porosity and permeability. The direction and rates of these reactions are influenced by several factors including properties that are associated with the brine system. Consequently, understanding and quantifying the impacts of the chemical and physical properties of the reacting fluids on overall reaction kinetics is fundamental to predicting the fate of the injected CO2. In this work, we present a comprehensive experimental study of the kinetics of carbonate-mineral dissolution in different brine systems including sodium chloride, sodium sulphate and sodium bicarbonate of varying ionic strengths. The impacts of the brine chemistry on rock-fluid chemical reactions at different extent of reactions are also investigated. Using a rotating disk technique, we have investigated the chemical interactions between the CO2-saturated brines and carbonate minerals at conditions of pressure (up to 10 MPa) and temperature (up to 373 K) pertinent to carbon storage. The changes in surface textures due to dissolution reaction were studied by means of optical microscopy and vertical scanning interferometry. Experimental results are compared to previously derived models.

  20. Influence of reaction conditions and type of alcohol on biodiesel yields and process economics of supercritical transesterification

    International Nuclear Information System (INIS)

    Micic, Radoslav D.; Tomić, Milan D.; Kiss, Ferenc E.; Nikolić-Djorić, Emilija B.; Simikić, Mirko Ð.

    2014-01-01

    Highlights: • Transesterification in supercritical methanol, ethanol and 1-propanol investigated. • Effect of alcohol, reaction temperature, pressure and time on yields analyzed. • Temperature has the highest impact on yield, followed by time and pressure. • Direct material and energy costs for each of the production alternatives estimated. • Lowest costs are achieved at highest yields even at very low oil prices. - Abstract: Experiments with transesterification of rapeseed oil in supercritical alcohols (methanol, ethanol and 1-propanol) were carried out in a batch reactor at various reaction temperatures (250–350 °C), working pressure (8–12 MPa), reaction time, and constant 42:1 alcohol to oil molar ratio. Influence of different alcohols and reaction conditions on biodiesel yield was investigated using linear multiple regression models. Temperature had the highest impact on yields, followed by reaction time and pressure. With increased molecular weight of alcohols, relative importance of temperature for explanation of yields decreased and relative importance of time and pressure increased. Economic assessment has revealed that transesterification in supercritical methanol has the lowest direct material and energy costs. Yield has crucial impact on process economics. Direct costs decrease with increase in biodiesel yields. Even at very low prices of oil feedstock the lowest cost is achieved at the highest yield

  1. Outcome of homogeneous and heterogeneous reactions in Darcy-Forchheimer flow with nonlinear thermal radiation and convective condition

    Directory of Open Access Journals (Sweden)

    T. Hayat

    Full Text Available The present analysis aims to report the consequences of nonlinear radiation, convective condition and heterogeneous-homogeneous reactions in Darcy-Forchheimer flow over a non-linear stretching sheet with variable thickness. Non-uniform magnetic field and nonuniform heat generation/absorption are accounted. The governing boundary layer partial differential equations are converted into a system of nonlinear ordinary differential equations. The computations are organized and the effects of physical variables such as thickness parameter, power index, Hartman number, inertia and porous parameters, radiation parameter, Biot number, Prandtl number, ratio parameter, heat generation parameter and homogeneous-heterogeneous reaction parameter are investigated. The variations of skin friction coefficient and Nusselt number for different interesting variables are plotted and discussed. It is noticed that Biot number and heat generation variable lead to enhance the temperature distribution. The solutal boundary layer thickness decreases for larger homogeneous variable while reverse trend is seen for heterogeneous reaction. Keywords: Variable sheet thickness, Darcy-Forchheimer flow, Homogeneous-heterogeneous reactions, Power-law surface velocity, Convective condition, Heat generation/absorption, Nonlinear radiation

  2. Mechanistic models for the evaluation of biocatalytic reaction conditions and biosensor design optimization

    DEFF Research Database (Denmark)

    Semenova, Daria

    . In the first case study a mechanistic model was developed to describe the enzymatic reaction of glucose oxidase and glucose in the presence of catalase inside a commercial microfluidic platform with integrated oxygen sensor spots. The simplicity of the proposed model allowed an easy calibration of the reaction...... the microfluidic device. In the second case study the flexible microfluidic platform with integrated amperometric glucose biosensors was developed for continuous monitoring of glucose consumption rates. The integration of the mixing chamber inside the platform allowed performing sample dilutions which subsequently......BRs. In the third case study the mechanistic model of the cyclic voltammetry response of the first generation glucose biosensors was developed and applied for the biosensor design optimization. Furthermore the obtained qualitative and quantitative dependencies between the model output and experimental results were...

  3. Computer simulation of the steam--graphite reaction under isothermal and steady-state conditions

    International Nuclear Information System (INIS)

    Joy, D.S.; Stem, S.C.

    1975-05-01

    A mathematical model was formulated to describe the isothermal, steady-state diffusion and reaction of steam in a graphite matrix. A generalized Langmuir-Hinshelwood equation is used to represent the steam-graphite reaction rate. The model also includes diffusion in the gas phase adjacent to the graphite matrix. A computer program, written to numerically integrate the resulting differential equations, is described. The coupled nonlinear differential equations in the graphite phase are solved using the IBM Continuous System Modeling Program. Classical finite difference techniques are used for the gas-phase calculations. An iterative procedure is required to couple the two sets of calculations. Several sample problems are presented to demonstrate the utility of the model. (U.S.)

  4. An effective rate equation approach to reaction kinetics in small volumes: theory and application to biochemical reactions in nonequilibrium steady-state conditions.

    Science.gov (United States)

    Grima, R

    2010-07-21

    Chemical master equations provide a mathematical description of stochastic reaction kinetics in well-mixed conditions. They are a valid description over length scales that are larger than the reactive mean free path and thus describe kinetics in compartments of mesoscopic and macroscopic dimensions. The trajectories of the stochastic chemical processes described by the master equation can be ensemble-averaged to obtain the average number density of chemical species, i.e., the true concentration, at any spatial scale of interest. For macroscopic volumes, the true concentration is very well approximated by the solution of the corresponding deterministic and macroscopic rate equations, i.e., the macroscopic concentration. However, this equivalence breaks down for mesoscopic volumes. These deviations are particularly significant for open systems and cannot be calculated via the Fokker-Planck or linear-noise approximations of the master equation. We utilize the system-size expansion including terms of the order of Omega(-1/2) to derive a set of differential equations whose solution approximates the true concentration as given by the master equation. These equations are valid in any open or closed chemical reaction network and at both the mesoscopic and macroscopic scales. In the limit of large volumes, the effective mesoscopic rate equations become precisely equal to the conventional macroscopic rate equations. We compare the three formalisms of effective mesoscopic rate equations, conventional rate equations, and chemical master equations by applying them to several biochemical reaction systems (homodimeric and heterodimeric protein-protein interactions, series of sequential enzyme reactions, and positive feedback loops) in nonequilibrium steady-state conditions. In all cases, we find that the effective mesoscopic rate equations can predict very well the true concentration of a chemical species. This provides a useful method by which one can quickly determine the

  5. Effect of thermal treatment conditions on properties of vanadium molybdenum oxide catalyst in acrolein oxidation reaction to acrylic acid

    International Nuclear Information System (INIS)

    Gorshkova, T.P.; Tarasova, D.V.; Olen'kova, I.P.; Andrushkevich, T.V.; Nikoro, T.A.

    1984-01-01

    The effect of thermal treatment conditions (temperature and gas medium) on properties of vanadium molybdenum oxide catalyst in acrolein oxidation reaction to acrylic acid is investigated. It is shown that active and selective catalysts are formed in the course of thermal decomposition of the drying product of ammonium metavanadate and paramolybdate under the conditions ensuring the vanadium ion reduction up to tetravalent state with conservation of molybdenum oxidation degree equal to 6. It is possible to realize it either by treatment of the catalyst calcinated in the air flow at 300 deg by the reaction mixture at the activation stage or by gas-reducer flow treatment at 280 deg. Thermal treatment in the reducing medium of the oxidized catalyst does not lead to complete regeneration of its properties

  6. A study of different indicators of Maillard reaction with whey proteins and different carbohydrates under adverse storage conditions.

    Science.gov (United States)

    Leiva, Graciela E; Naranjo, Gabriela B; Malec, Laura S

    2017-01-15

    This study examined different indicators of each stage of Maillard reaction under adverse storage conditions in a system with whey proteins and lactose or glucose. The analysis of lysine loss by the o-phthaldialdehyde method can be considered a good indicator of the early stage, showing considerable differences in reactivity when systems with mono and disaccharides were analyzed. Capillary electrophoresis proved to be a sensitive method for evaluating the extent of glycosylation of the native proteins, providing valuable information when the loss of lysine was not significant. The estimation of the Amadori compound from the determination of total 5-hydroxymethyl-2-furfuraldehyde would have correlate well with reactive lysine content if the advanced stages of the reaction had not been reached. For assessing the occurrence of the intermediate and final stages, the measurement of free 5-hydroxymethyl-2-furfuraldehyde and color, proved not to be suitable for storage conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Prompt HO2 formation following the reaction of OH with aromatic compounds under atmospheric conditions.

    Science.gov (United States)

    Nehr, Sascha; Bohn, Birger; Wahner, Andreas

    2012-06-21

    The secondary formation of HO(2) radicals following OH + aromatic hydrocarbon reactions in synthetic air under normal pressure and temperature was investigated in the absence of NO after pulsed production of OH radicals. OH and HO(x) (=OH + HO(2)) decay curves were recorded using laser-induced fluorescence after gas-expansion. The prompt HO(2) yields (HO(2) formed without preceding NO reactions) were determined by comparison to results obtained with CO as a reference compound. This approach was recently introduced and applied to the OH + benzene reaction and was extended here for a number of monocyclic aromatic hydrocarbons. The measured HO(2) formation yields are as follows: toluene, 0.42 ± 0.11; ethylbenzene, 0.53 ± 0.10; o-xylene, 0.41 ± 0.08; m-xylene, 0.27 ± 0.06; p-xylene, 0.40 ± 0.09; 1,2,3-trimethylbenzene, 0.31 ± 0.06; 1,2,4-trimethylbenzene, 0.37 ± 0.09; 1,3,5-trimethylbenzene, 0.29 ± 0.08; hexamethylbenzene, 0.32 ± 0.08; phenol, 0.89 ± 0.29; o-cresol, 0.87 ± 0.29; 2,5-dimethylphenol, 0.72 ± 0.12; 2,4,6-trimethylphenol, 0.45 ± 0.13. For the alkylbenzenes HO(2) is the proposed coproduct of phenols, epoxides, and possibly oxepins formed in secondary reactions with O(2). In most product studies the only quantified coproducts were phenols whereas only a few studies reported yields of epoxides. Oxepins have not been observed so far. Together with the yields of phenols from other studies, the HO(2) yields determined in this work set an upper limit to the combined yields of epoxides and oxepins that was found to be significant (≤0.3) for all investigated alkylbenzenes except m-xylene. For the hydroxybenzenes the currently proposed HO(2) coproducts are dihydroxybenzenes. For phenol and o-cresol the determined HO(2) yields are matching the previously reported dihydroxybenzene yields, indicating that these are the only HO(2) forming reaction channels. For 2,5-dimethylphenol and 2,4,6-trimethylphenol no complementary product studies are available.

  8. Fibrous nano-silica (KCC-1)-supported palladium catalyst: Suzuki coupling reactions under sustainable conditions

    KAUST Repository

    Fihri, Aziz; Cha, Dong Kyu; Bouhrara, Mohamed; Al Mana, Noor; Polshettiwar, Vivek

    2011-01-01

    Noble amines recycled: Fibrous high-surface-area nano-silica functionalized with aminopropyl groups and loaded with well-dispersed Pd nanoparticles is evaluated for the Suzuki coupling of aromatic halides. It is active for the reaction of a range of aryl bromides and iodides as well as chlorides with aryl boronic acids in good to excellent yields. The catalyst can be recovered and reused for a number of cycles with negligible loss in activity. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Fibrous nano-silica (KCC-1)-supported palladium catalyst: Suzuki coupling reactions under sustainable conditions

    KAUST Repository

    Fihri, Aziz

    2011-11-15

    Noble amines recycled: Fibrous high-surface-area nano-silica functionalized with aminopropyl groups and loaded with well-dispersed Pd nanoparticles is evaluated for the Suzuki coupling of aromatic halides. It is active for the reaction of a range of aryl bromides and iodides as well as chlorides with aryl boronic acids in good to excellent yields. The catalyst can be recovered and reused for a number of cycles with negligible loss in activity. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Influence of growth conditions and surface reaction byproducts on GaN grown via metal organic molecular beam epitaxy: Toward an understanding of surface reaction chemistry

    Science.gov (United States)

    Pritchett, David; Henderson, Walter; Burnham, Shawn D.; Doolittle, W. Alan

    2006-04-01

    The surface reaction byproducts during the growth of GaN films via metal organic molecular beam epitaxy (MOMBE) were investigated as a means to optimize material properties. Ethylene and ethane were identified as the dominant surface reaction hydrocarbon byproducts, averaging 27.63% and 7.15% of the total gas content present during growth. Intense ultraviolet (UV) photoexcitation during growth was found to significantly increase the abundance of ethylene and ethane while reducing the presence of H2 and N2. At 920°C, UV excitation was shown to enhance growth rate and crystalline quality while reducing carbon incorporation. Over a limited growth condition range, a 4.5×1019-3.4×1020 cm-3 variation in carbon incorporation was achieved at constant high vacuum. Coupled with growth rate gains, UV excitation yielded films with ˜58% less integrated carbon content. Structural material property variations are reported for various ammonia flows and growth temperatures. The results suggest that high carbon incorporation can be achieved and regulated during MOMBE growth and that in-situ optimization through hydrocarbon analysis may provide further enhancement in the allowable carbon concentration range.

  11. Safety analysis of switching between reductive and oxidative conditions in a reaction coupling reverse flow reactor.

    NARCIS (Netherlands)

    van Sint Annaland, M.; Kuipers, J.A.M.; van Swaaij, Willibrordus Petrus Maria

    2001-01-01

    A new reverse flow reactor is developed where endothermic reactants (propane dehydrogenation) and exothermic reactants (fuel combustion) are fed sequentially to a monolithic catalyst, while periodically alternating the inlet and outlet positions. Upon switching from reductive to oxidative conditions

  12. Photoprotection through ultrafast charge recombination in photochemical reaction centres under oxidizing conditions

    NARCIS (Netherlands)

    Ma, Fei; Swainsbury, David J. K.; Jones, Michael R.; van Grondelle, Rienk

    2017-01-01

    Engineering natural photosynthesis to address predicted shortfalls in food and energy supply requires a detailed understanding of its molecular basis and the intrinsic photoprotective mechanisms that operate under fluctuating environmental conditions. Long-lived triplet or singlet excited electronic

  13. Polymerization of Acetonitrile via a Hydrogen Transfer Reaction from CH3 to CN under Extreme Conditions.

    Science.gov (United States)

    Zheng, Haiyan; Li, Kuo; Cody, George D; Tulk, Christopher A; Dong, Xiao; Gao, Guoying; Molaison, Jamie J; Liu, Zhenxian; Feygenson, Mikhail; Yang, Wenge; Ivanov, Ilia N; Basile, Leonardo; Idrobo, Juan-Carlos; Guthrie, Malcolm; Mao, Ho-Kwang

    2016-09-19

    Acetonitrile (CH3 CN) is the simplest and one of the most stable nitriles. Reactions usually occur on the C≡N triple bond, while the C-H bond is very inert and can only be activated by a very strong base or a metal catalyst. It is demonstrated that C-H bonds can be activated by the cyano group under high pressure, but at room temperature. The hydrogen atom transfers from the CH3 to CN along the CH⋅⋅⋅N hydrogen bond, which produces an amino group and initiates polymerization to form a dimer, 1D chain, and 2D nanoribbon with mixed sp(2) and sp(3) bonded carbon. Finally, it transforms into a graphitic polymer by eliminating ammonia. This study shows that applying pressure can induce a distinctive reaction which is guided by the structure of the molecular crystal. It highlights the fact that very inert C-H can be activated by high pressure, even at room temperature and without a catalyst. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Study on the phosphate reaction characteristics of lanthanide chlorides in molten salt with operating conditions

    International Nuclear Information System (INIS)

    Lee, Tae-Kyo; Hwang, Taek-Sung; Cho, Yung-Zun; Eun, Hee-Chul; Park, Hwan-Seo; Park, Geun-Il; Son, Sung-Mo

    2013-01-01

    A minimization of waste salt is one of the most important issues for the optimization of pyroprocessing. The separation of fission products in waste salts and the reuse of purified waste salt are promising strategies for minimizing the waste salt amounts. The phosphate precipitation of lanthanide is currently being considered for eutectic (LiCl–KCl) waste salt purification. In this research, the effects of molten salt temperature (400–550°C) and reaction time (max. 180 min) upon conversion into the phosphate of lanthanides was investigated using 1 and 3 kg of eutectic salt. The conversion efficiency of lanthanides to molten salt-insoluble precipitates and phosphates was increased with an increase in molten salt temperature and operating time until it attained a specific temperature and time. K 3 PO 4 as a precipitant was more favorable than Li 3 PO 4 in terms of reactivity. To obtain over a 99% overall conversion efficiency, about 30 min was required in the case of using K 3 PO 4 at 450°C, but about 120 min in the case of using Li 3 PO 4 at 550°C. The lanthanide precipitates formed by a reaction with phosphate were a mixture of monoclinic structures, usually representing a polyhedron structure, and a tetragonal structure, representing a platelet structure. (author)

  15. Reaction Norms in Natural Conditions: How Does Metabolic Performance Respond to Weather Variations in a Small Endotherm Facing Cold Environments?

    Science.gov (United States)

    Petit, Magali; Vézina, François

    2014-01-01

    Reaction norms reflect an organisms' capacity to adjust its phenotype to the environment and allows for identifying trait values associated with physiological limits. However, reaction norms of physiological parameters are mostly unknown for endotherms living in natural conditions. Black-capped chickadees (Poecile atricapillus) increase their metabolic performance during winter acclimatization and are thus good model to measure reaction norms in the wild. We repeatedly measured basal (BMR) and summit (Msum) metabolism in chickadees to characterize, for the first time in a free-living endotherm, reaction norms of these parameters across the natural range of weather variation. BMR varied between individuals and was weakly and negatively related to minimal temperature. Msum varied with minimal temperature following a Z-shape curve, increasing linearly between 24°C and −10°C, and changed with absolute humidity following a U-shape relationship. These results suggest that thermal exchanges with the environment have minimal effects on maintenance costs, which may be individual-dependent, while thermogenic capacity is responding to body heat loss. Our results suggest also that BMR and Msum respond to different and likely independent constraints. PMID:25426860

  16. Malonic acid concentration as a control parameter in the kinetic analysis of the Belousov-Zhabotinsky reaction under batch conditions.

    Science.gov (United States)

    Blagojević, Slavica M; Anić, Slobodan R; Cupić, Zeljko D; Pejić, Natasa D; Kolar-Anić, Ljiljana Z

    2008-11-28

    The influence of the initial malonic acid concentration [MA]0 (8.00 x 10(-3) sulfuric acid (1.00 mol dm(-3)) and cerium sulfate (2.50 x 10(-3) mol dm(-3)) on the dynamics and the kinetics of the Belousov-Zhabotinsky (BZ) reactions was examined under batch conditions at 30.0 degrees C. The kinetics of the BZ reaction was analyzed by the earlier proposed method convenient for the examinations of the oscillatory reactions. In the defined region of parameters where oscillograms with only large-amplitude relaxation oscillations appeared, the pseudo-first order of the overall malonic acid decomposition with a corresponding rate constant of 2.14 x 10(-2) min(-1) was established. The numerical results on the dynamics and kinetics of the BZ reaction, carried out by the known skeleton model including the Br2O species, were in good agreement with the experimental ones. The already found saddle node infinite period (SNIPER) bifurcation point in transition from a stable quasi-steady state to periodic orbits and vice versa is confirmed by both experimental and numerical investigations of the system under consideration. Namely, the large-amplitude relaxation oscillations with increasing periods between oscillations in approaching the bifurcation points at the beginning and the end of the oscillatory domain, together with excitability of the stable quasi-steady states in their vicinity are obtained.

  17. Preparation of ionic-crosslinked chitosan-based gel beads and effect of reaction conditions on drug release behaviors.

    Science.gov (United States)

    Chen, Shilan; Liu, Mingzhu; Jin, Shuping; Wang, Bin

    2008-02-12

    Drug-loaded chitosan (CS) beads were prepared under simple and mild condition using trisodium citrate as ionic crosslinker. The beads were further coated with poly(methacrylic acid) (PMAA) by dipping the beads in PMAA aqueous solution. The surface and cross-section morphology of these beads were observed by scanning electron microscopy and the observation showed that the coating beads had core-shell structure. In vitro release of model drug from these beads obtained under different reaction conditions was investigated in buffer medium (pH 1.8). The results showed that the rapid drug release was restrained by PMAA coating and the optimum conditions for preparing CS-based drug-loaded beads were decided through the effect of reaction conditions on the drug release behaviors. In addition, the drug release mechanism of CS-based drug-loaded beads was analyzed by Peppa's potential equation. According to this study, the ionic-crosslinked CS beads coated by PMAA could serve as suitable candidate for drug site-specific carrier in stomach.

  18. Hot-Fire Testing of 100 LB(sub F) LOX/LCH4 Reaction Control Engine at Altitude Conditions

    Science.gov (United States)

    Marshall, William M.; Kleinhenz, Julie E.

    2010-01-01

    Liquid oxygen/liquid methane (LO2/LCH4 ) has recently been viewed as a potential green propulsion system for both the Altair ascent main engine (AME) and reaction control system (RCS). The Propulsion and Cryogenic Advanced Development Project (PCAD) has been tasked by NASA to develop these green propellant systems to enable safe and cost effective exploration missions. However, experience with LO2/LCH4 as a propellant combination is limited, so testing of these systems is critical to demonstrating reliable ignition and performance. A test program of a 100 lb f reaction control engine (RCE) is underway at the Altitude Combustion Stand (ACS) of the NASA Glenn Research Center, with a focus on conducting tests at altitude conditions. These tests include a unique propellant conditioning feed system (PCFS) which allows for the inlet conditions of the propellant to be varied to test warm to subcooled liquid propellant temperatures. Engine performance, including thrust, c* and vacuum specific impulse (I(sub sp,vac)) will be presented as a function of propellant temperature conditions. In general, the engine performed as expected, with higher performance at warmer propellant temperatures but better efficiency at lower propellant temperatures. Mixture ratio effects were inconclusive within the uncertainty bands of data, but qualitatively showed higher performance at lower ratios.

  19. Identification of alterations in the Jacobian of biochemical reaction networks from steady state covariance data at two conditions.

    Science.gov (United States)

    Kügler, Philipp; Yang, Wei

    2014-06-01

    Model building of biochemical reaction networks typically involves experiments in which changes in the behavior due to natural or experimental perturbations are observed. Computational models of reaction networks are also used in a systems biology approach to study how transitions from a healthy to a diseased state result from changes in genetic or environmental conditions. In this paper we consider the nonlinear inverse problem of inferring information about the Jacobian of a Langevin type network model from covariance data of steady state concentrations associated to two different experimental conditions. Under idealized assumptions on the Langevin fluctuation matrices we prove that relative alterations in the network Jacobian can be uniquely identified when comparing the two data sets. Based on this result and the premise that alteration is locally confined to separable parts due to network modularity we suggest a computational approach using hybrid stochastic-deterministic optimization for the detection of perturbations in the network Jacobian using the sparsity promoting effect of [Formula: see text]-penalization. Our approach is illustrated by means of published metabolomic and signaling reaction networks.

  20. Constitution and reaction behavior of LWR materials at core melting conditions

    International Nuclear Information System (INIS)

    Holleck, H.; Skokan, A.; Janzer, H.; Schlickeise, G.; Riemueller, K.; Stroemann, H.; Nold, E.; Schaefer, A.

    1979-01-01

    Crucible melting experiments were performed with mixtures of preoxidized corium and basaltic or limestone concrete in order to investigate the oxidation behavior of the fission products, esp. Mo and Ru, at elevated oxygen partial pressures by H 2 O and CO 2 released from concrete. - The solidification behavior of the metallic and oxide fractions of corium (A+R) and corium (E+R) in the course of the interaction with basaltic or limestone concrete was investigated by crucible experiments. -Thermoanalytical investigations were performed with concrete of different types ranging from pure basaltic to pure limestone aggregates in order to test the possibility of reactions between CaO and SiO 2 during the heating up period. (orig./RW) [de

  1. Effect of reaction conditions on film morphology of polyaniline composite membranes for gas separation

    KAUST Repository

    Blinova, Natalia V.

    2012-04-21

    Composite membranes combining polyaniline as an active layer with a polypropylene support have been prepared using an in situ deposition technique. The protonated polyaniline layer with a thickness in the range of 90-200 nm was prepared using precipitation, dispersion, or emulsion polymerization of aniline with simultaneous deposition on top of the porous polypropylene support, which was immersed in the reaction mixture. Variables such as temperature, concentration of reagents, presence of steric stabilizers, surfactants, and heteropolyacid were found to control both the formation and the quality of the polyaniline layers. Both morphology and thickness of the layers were characterized using scanning electron microscopy. Selective separation of carbon dioxide from its mixture with methane is used to illustrate potential application of these composite membranes. © 2012 Wiley Periodicals, Inc.

  2. The necessary and sufficient conditions of therapeutic personality change: Reactions to Rogers' 1957 article.

    Science.gov (United States)

    Samstag, Lisa Wallner

    2007-09-01

    Carl Rogers' article (see record 2007-14639-002) on the necessary and sufficient conditions for personality change has had a significant impact on the field of psychotherapy and psychotherapy research. He emphasized the client as arbiter of his or her own subjective experience and tested his hypothesized therapist-offered conditions of change using recorded sessions. This aided in demystifying the therapeutic process and led to a radical shift in the listening stance of the therapist. I briefly outline my views regarding the influence of the ideas presented in this work, describe the intellectual and cultural context of the times, and discuss a number of ways in which the therapist-offered conditions for psychological transformation are neither necessary nor sufficient. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

  3. Global exponential stability and periodicity of reaction-diffusion recurrent neural networks with distributed delays and Dirichlet boundary conditions

    International Nuclear Information System (INIS)

    Lu Junguo; Lu Linji

    2009-01-01

    In this paper, global exponential stability and periodicity of a class of reaction-diffusion recurrent neural networks with distributed delays and Dirichlet boundary conditions are studied by constructing suitable Lyapunov functionals and utilizing some inequality techniques. We first prove global exponential convergence to 0 of the difference between any two solutions of the original neural networks, the existence and uniqueness of equilibrium is the direct results of this procedure. This approach is different from the usually used one where the existence, uniqueness of equilibrium and stability are proved in two separate steps. Secondly, we prove periodicity. Sufficient conditions ensuring the existence, uniqueness, and global exponential stability of the equilibrium and periodic solution are given. These conditions are easy to verify and our results play an important role in the design and application of globally exponentially stable neural circuits and periodic oscillatory neural circuits.

  4. Spatial variation in growth, condition and maturation reaction norms of the Baltic herring Clupea harengus membras

    NARCIS (Netherlands)

    Vainikka, A.; Mollet, F.M.; Casini, M.; Gardmark, A.

    2009-01-01

    Understanding of spatial patterns in life-history traits can help fisheries management focus on biologically and functionally relevant stock units. In the present study, we examined life-history variation in growth, condition and maturation of the Baltic herring Clupea harengus membras among

  5. Multiscale Modeling of Poly(lactic acid) Production: From Reaction Conditions to Rheology of Polymer Melt

    DEFF Research Database (Denmark)

    Zubov, Alexandr; Sin, Gürkan

    2018-01-01

    Abstract Poly(L-lactic acid) (PLLA) is a fully biodegradable bioplastic with promising market potential. The paper deals with systematic development and analysis of the modeling framework allowing direct mapping between PLLA production process conditions and rheological properties of the polymer ...

  6. Optimizing Chemical Reactions with Deep Reinforcement Learning.

    Science.gov (United States)

    Zhou, Zhenpeng; Li, Xiaocheng; Zare, Richard N

    2017-12-27

    Deep reinforcement learning was employed to optimize chemical reactions. Our model iteratively records the results of a chemical reaction and chooses new experimental conditions to improve the reaction outcome. This model outperformed a state-of-the-art blackbox optimization algorithm by using 71% fewer steps on both simulations and real reactions. Furthermore, we introduced an efficient exploration strategy by drawing the reaction conditions from certain probability distributions, which resulted in an improvement on regret from 0.062 to 0.039 compared with a deterministic policy. Combining the efficient exploration policy with accelerated microdroplet reactions, optimal reaction conditions were determined in 30 min for the four reactions considered, and a better understanding of the factors that control microdroplet reactions was reached. Moreover, our model showed a better performance after training on reactions with similar or even dissimilar underlying mechanisms, which demonstrates its learning ability.

  7. Reaction of the Lithuanian alfalfa breeding populations to Phoma medicaginis under cool temperate climate conditions

    International Nuclear Information System (INIS)

    Liatukiene, A.; Liatukas, Z.; Ruzgas, V.

    2015-01-01

    The alfalfa Phoma medicaginis resistance was evaluated on 100 accessions with different development date. Weather conditions favoured high disease pressure and differentiation of tested accessions was not clear in 2011. Accessions were compared by maximal disease severity (DS) and area under disease progress curve (AUDPC). DS ranged from 10 to 60% and AUDPC value ranged 119-727 in 2009. DS and AUDPC values were higher in 2010 and 2011, DS ranged 40-65 and 66-68% and AUDPC ranged 2263-2928 and 2853-3006. Development date of accessions showed low impact on resistance. The correlations between DS and AUDPC results of accessions across years highly varied (r=0.189 - 0.828) due to low differentiation of accessions resistance. Selection of alfalfa material promising by Phoma medicaginis resistance should be done under conditions moderately favourable for development of this disease. (author)

  8. Lipid synthesis under hydrothermal conditions by Fischer-Tropsch-type reactions.

    Science.gov (United States)

    McCollom, T M; Ritter, G; Simoneit, B R

    1999-03-01

    Ever since their discovery in the late 1970's, mid-ocean-ridge hydrothermal systems have received a great deal of attention as a possible site for the origin of life on Earth (and environments analogous to mid-ocean-ridge hydrothermal systems are postulated to have been sites where life could have originated or Mars and elsewhere as well). Because no modern-day terrestrial hydrothermal systems are free from the influence of organic compounds derived from biologic processes, laboratory experiments provide the best opportunity for confirmation of the potential for organic synthesis in hydrothermal systems. Here we report on the formation of lipid compounds during Fischer-Tropsch-type synthesis from aqueous solutions of formic acid or oxalic acid. Optimum synthesis occurs in stainless steel vessels by heating at 175 degrees C for 2-3 days and produces lipid compounds ranging from C2 to > C35 which consist of n-alkanols, n-alkanoic acids, n-alkenes, n-alkanes and alkanones. The precursor carbon sources used are either formic acid or oxalic acid, which disproportionate to H2, CO2 and probably CO. Both carbon sources yield the same lipid classes with essentially the same ranges of compounds. The synthesis reactions were confirmed by using 13C labeled precursor acids.

  9. Fast Curing Bio-Based Phenolic Resins via Lignin Demethylated under Mild Reaction Condition

    OpenAIRE

    Jiongjiong Li; Jizhi Zhang; Shifeng Zhang; Qiang Gao; Jianzhang Li; Wei Zhang

    2017-01-01

    Demethylation technique has been used to enhance lignin reactivity for preparation of phenolic resins. However, the demethylation efficiency and the demethylated lignin (DL) reactivity were still unsatisfactory. To improve the demethylation efficiency, alkali lignin was demethylated under different mild conditions using sodium sulfite as a catalyst. Lignin and DL were characterized by 1H-NMR (nuclear magnetic resonance) and Fourier transform infrared (FT-IR) spectroscopy to determine the deme...

  10. The influence of processing conditions on the microstructure and the mechanical properties of reaction sintered silicon nitride

    International Nuclear Information System (INIS)

    Heinrich, J.

    1979-09-01

    The microstructure of reaction sintered silicon nitride (RBSN) was changed in a wide range of varying green density, grain size of the silicon starting powder, nitriding conditions, and by introducing artificial pores. The influence of single microstructural parameters on mechanical properties like room temperature strength, creep behaviour, and resistance to thermal shock has been investigated. The essential factors influencing these properties were found to be total porosity, pore size distribution, and the fractions of α- and β-Si 3 N 4 . In view of high temperature engineering applications of RBSN possibilities to optimize the material's properties by controlled processing are discussed. (orig.) [de

  11. Optimization of reaction conditions for enzymatic viscosity reduction and hydrolysis of wheat arabinoxylan in an industrial ethanol fermentation residue

    DEFF Research Database (Denmark)

    Sørensen, H.R.; Pedersen, S.; Meyer, Anne Boye Strunge

    2006-01-01

    with a 50:50 mixture of an enzyme preparation from Humicola insolens, Ultraflo L, and a cellulolytic enzyme preparation from Trichoderma reesei, Celluclast 1.5 L. This enzyme mixture was previously shown to exhibit a synergistic action on arabinoxylan degradation. The viscosity of vinasse decreased...... of enzyme-catalyzed hydrolysis of arabinoxylan, beta-glucan, and cellulose. In designed response surface experiments, the optimal enzyme reaction conditions with respect to pH and temperature of the vinasse, the vinasse supernatant (mainly soluble material), and the vinasse sediment (mainly insoluble...

  12. Basic visualization experiments on eutectic reaction of boron carbide and stainless steel under sodium-cooled fast reactor conditions

    International Nuclear Information System (INIS)

    Yamano, Hidemasa; Suzuki, Tohru; Kamiyama, Kenji; Kudo, Isamu

    2016-01-01

    This paper describes basic visualization experiments on eutectic reaction and relocation of boron carbide (B 4 C) and stainless steel (SS) under a high temperature condition exceeding 1500degC as well as the importance of such behaviors in molten core during a core disruptive accident in a Generation-IV sodium-cooled fast reactor (750 MWe class) designed in Japan. At first, a reactivity history was calculated using an exact perturbation calculation tool taking into account expected behaviors. This calculation indicated the importance of a relocation behavior of the B 4 C-SS eutectic because its behavior has a large uncertainty in the reactivity history. To clarify this behavior, basic experiments were carried out by visualizing the reaction of a B 4 C pellet contacted with molten SS in a high temperature-heating furnace. The experiments have shown the eutectic reaction visualization as well as freezing and relocation of the B 4 C-SS eutectic in upper part of the solidified test piece due to the density separation. (author)

  13. Biodiesel production from various oils under supercritical fluid conditions by Candida antartica lipase B using a stepwise reaction method.

    Science.gov (United States)

    Lee, Jong Ho; Kwon, Cheong Hoon; Kang, Jeong Won; Park, Chulhwan; Tae, Bumseok; Kim, Seung Wook

    2009-05-01

    In this study, we evaluate the effects of various reaction factors, including pressure, temperature, agitation speed, enzyme concentration, and water content to increase biodiesel production. In addition, biodiesel was produced from various oils to establish the optimal enzymatic process of biodiesel production. Optimal conditions were determined to be as follows: pressure 130 bar, temperature 45 degrees C, agitation speed 200 rpm, enzyme concentration 20%, and water contents 10%. Among the various oils used for production, olive oil showed the highest yield (65.18%) upon transesterification. However, when biodiesel was produced using a batch system, biodiesel conversion yield was not increased over 65%; therefore, a stepwise reaction was conducted to increase biodiesel production. When a reaction medium with an initial concentration of methanol of 60 mmol was used and adjusted to maintain this concentration of methanol every 1.5 h during biodiesel production, the conversion yield of biodiesel was 98.92% at 6 h. Finally, reusability was evaluated using immobilized lipase to determine if this method was applicable for industrial biodiesel production. When biodiesel was produced repeatedly, the conversion rate was maintained at over 85% after eight reuses.

  14. Influence of the reaction conditions on the enzyme catalyzed transesterification of castor oil: A possible step in biodiesel production.

    Science.gov (United States)

    Andrade, Thalles A; Errico, Massimiliano; Christensen, Knud V

    2017-11-01

    The identification of the influence of the reaction parameters is of paramount importance when defining a process design. In this work, non-edible castor oil was reacted with methanol to produce a possible component for biodiesel blends, using liquid enzymes as the catalyst. Temperature, alcohol-to-oil molar ratio, enzyme and added water contents were the reaction parameters evaluated in the transesterification reactions. The optimal conditions, giving the optimal final FAME yield and FFA content in the methyl ester-phase was identified. At 35°C, 6.0 methanol-to-oil molar ratio, 5wt% of enzyme and 5wt% of water contents, 94% of FAME yield and 6.1% of FFA in the final composition were obtained. The investigation was completed with the analysis of the component profiles, showing that at least 8h are necessary to reach a satisfactory FAME yield together with a minor FFA content. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Do Geriatric Conditions Increase Risk of Adverse Drug Reactions in Ambulatory Elders? Results From the VA GEM Drug Study

    Science.gov (United States)

    Hanlon, Joseph T.; Sloane, Richard J.; Boscardin, W. John; Schmader, Kenneth E.

    2011-01-01

    Background. Many clinicians prescribe cautiously to older adults with common geriatric conditions for fear of causing adverse drug reactions (ADRs). However, little is known about the association between these conditions and risk of ADRs. Methods. Using data from the VA Geriatric Evaluation and Management Drug Study, we determined any, preventable, and serious ADRs in 808 elders for 12 months after hospital discharge using a validated process involving patient self-report and chart review adjudicated by two health care professionals. Eight common geriatric conditions (activities of daily living, dementia, incontinence, falls, difficulty ambulating, malnourishment, depression, and prolonged bed rest) were evaluated at study baseline through self-report and structured assessments. We used Poisson regression to model the relationship between these geriatric conditions and ADRs. Results. Participants had a mean of 2.9 ± 1.2 geriatric conditions. Over the 12-month follow-up period, 497 ADRs occurred in 269 participants, including 187 ADRs considered preventable and 127 considered severe. On multivariable analyses, participants with dependency in one or more activities of daily living were less likely to suffer ADRs than those who were fully independent (incidence rate ratio: 0.78, 95% confidence interval = 0.62–1.00). None of the other seven geriatric conditions assessed were associated with ADR risk. Results were similar for preventable and serious ADRs, although participants with a history of falls were more likely to develop serious ADRs (incidence rate ratio: 1.49, 95% confidence interval = 1.00–2.21). Conclusions. Many geriatric conditions were not associated with risk of ADRs. Although it is prudent to prescribe judiciously in patients with these conditions, excessive caution may not be warranted. PMID:21321003

  16. Effects of reaction conditions on nuclear laundry water treatment in Fenton process

    International Nuclear Information System (INIS)

    Vilve, Miia; Hirvonen, Arja; Sillanpaeae, Mika

    2009-01-01

    This study presents the efficiency of Fenton process in the degradation of organic compounds of nuclear laundry water. The influence of Fe 2+ and hydrogen peroxide ratio, hydrogen peroxide dose, pH and treatment time were investigated. The degradation of non-ionic surfactant and other organic compounds was analysed as COD, TOC and molecular weight distribution (MWD). The most cost-effective degradation conditions were at H 2 O 2 /Fe 2+ stoichiometric molar ratio of 2 with 5 min mixing and H 2 O 2 dose of 1000 mg l -1 . With the initial pH of 6, the reductions of COD and TOC were 85% and 69%, respectively. However, the removal of the organic compounds was mainly carried out by Fenton-based Fe 3+ coagulation rather than Fenton oxidation. Fenton process proved to be much more efficient than previously performed ozone-based oxidation processes.

  17. QuadraPure-Supported Palladium Nanocatalysts for Microwave-Promoted Suzuki Cross-Coupling Reaction under Aerobic Condition

    Directory of Open Access Journals (Sweden)

    Kin Hong Liew

    2014-01-01

    Full Text Available Cross-linked resin-captured palladium (XL-QPPd was readily prepared by simple physical adsorption onto the high loading QuadraPure macroporous resin and a subsequent reduction process. To enhance the mechanical stability, entrapped palladium nanocatalysts were cross-linked with succinyl chloride. Both transmission electron microscopy images and X-ray diffraction analysis revealed that the palladium nanoparticles were well dispersed with diameters ranging in 4–10 nm. The catalyst performed good catalytic activity in microwave-promoted Suzuki cross-coupling reactions in water under aerobic condition with mild condition by using various aryl halides and phenylboronic acid. In addition, the catalyst showed an excellent recyclability without significant loss of catalytic activity.

  18. Effects of reaction conditions on the emission behaviors of arsenic, cadmium and lead during sewage sludge pyrolysis.

    Science.gov (United States)

    Han, Hengda; Hu, Song; Syed-Hassan, Syed Shatir A; Xiao, Yiming; Wang, Yi; Xu, Jun; Jiang, Long; Su, Sheng; Xiang, Jun

    2017-07-01

    Sewage sludge is an important class of bioresources whose energy content could be exploited using pyrolysis technology. However, some harmful trace elements in sewage sludge can escape easily to the gas phase during pyrolysis, increasing the potential of carcinogenic material emissions to the atmosphere. This study investigates emission characteristics of arsenic, cadmium and lead under different pyrolysis conditions for three different sewage sludge samples. The increased temperature (within 723-1123K) significantly promoted the cadmium and lead emissions, but its influence on arsenic emission was not pronounced. The releasing rate order of the three trace elements is volatile arsenic compounds>cadmium>lead in the beginning of pyrolysis. Fast heating rates promoted the emission of trace elements for the sludge containing the highest amount of ash, but exhibited an opposite effect for other studied samples. Overall, the high ash sludge released the least trace elements almost under all reaction conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Adaptive locomotor training on an end-effector gait robot: evaluation of the ground reaction forces in different training conditions.

    Science.gov (United States)

    Tomelleri, Christopher; Waldner, Andreas; Werner, Cordula; Hesse, Stefan

    2011-01-01

    The main goal of robotic gait rehabilitation is the restoration of independent gait. To achieve this goal different and specific patterns have to be practiced intensively in order to stimulate the learning process of the central nervous system. The gait robot G-EO Systems was designed to allow the repetitive practice of floor walking, stair climbing and stair descending. A novel control strategy allows training in adaptive mode. The force interactions between the foot and the ground were analyzed on 8 healthy volunteers in three different conditions: real floor walking on a treadmill, floor walking on the gait robot in passive mode, floor walking on the gait robot in adaptive mode. The ground reaction forces were measured by a Computer Dyno Graphy (CDG) analysis system. The results show different intensities of the ground reaction force across all of the three conditions. The intensities of force interactions during the adaptive training mode are comparable to the real walking on the treadmill. Slight deviations still occur in regard to the timing pattern of the forces. The adaptive control strategy comes closer to the physiological swing phase than the passive mode and seems to be a promising option for the treatment of gait disorders. Clinical trials will validate the efficacy of this new option in locomotor therapy on the patients. © 2011 IEEE

  20. Identification of a Catalytically Highly Active Surface Phase for CO Oxidation over PtRh Nanoparticles under Operando Reaction Conditions

    Science.gov (United States)

    Hejral, U.; Franz, D.; Volkov, S.; Francoual, S.; Strempfer, J.; Stierle, A.

    2018-03-01

    Pt-Rh alloy nanoparticles on oxide supports are widely employed in heterogeneous catalysis with applications ranging from automotive exhaust control to energy conversion. To improve catalyst performance, an atomic-scale correlation of the nanoparticle surface structure with its catalytic activity under industrially relevant operando conditions is essential. Here, we present x-ray diffraction data sensitive to the nanoparticle surface structure combined with in situ mass spectrometry during near ambient pressure CO oxidation. We identify the formation of ultrathin surface oxides by detecting x-ray diffraction signals from particular nanoparticle facets and correlate their evolution with the sample's enhanced catalytic activity. Our approach opens the door for an in-depth characterization of well-defined, oxide-supported nanoparticle based catalysts under operando conditions with unprecedented atomic-scale resolution.

  1. Defense reactions of bean genotypes to bacterial pathogens in controlled conditions

    Science.gov (United States)

    Uysal, B.; Bastas, K. K.

    2018-03-01

    This study was focused on the role of antioxidant enzymes and total protein in imparting resistance against common bacterial blight caused by Xanthomonas axonopodis pv. phaseoli (Xap) and halo blight caused by Pseudomonas syringae pv. phaseolicola (Psp) in bean. Activities of Ascorbate peroxidase (APX), Catalase (CAT) and total protein were studied in resistant and susceptible bean genotypes. Five-day-old seedlings were inoculated with a bacterial suspension (108 CFU ml-1) and harvested at different time intervals (0, 12, 24 and 36 up to 72 h) under controlled growing conditions and assayed for antioxidant enzymes and total protein. Temporal increase of CAT, APX enzymes activities showed maximum activity at 12 h after both pathogens inoculation (hpi) in resistant cultivar, whereas in susceptible it increased at 72 h after both pathogens inoculation for CAT and 12, 24 h for APX enzymes. Maximum total protein activities were observed at 12 h and 24 h respectively after Xap, Psp inoculation (hpi) in resistant and maximum activities were observed at 24 h and 72 h respectively after Xap, Psp inoculation (hpi) in susceptible. Increase of antioxidant enzyme and total protein activities might be an important component in the defense strategy of resistance and susceptible bean genotypes against the bacterial infection. These findings suggest that disease protection is proportional to the amount of enhanced CAT, APX enzyme and total protein activity.

  2. A case study employing operant conditioning to reduce stress of capture for red-bellied tamarins (Saguinus labiatus).

    Science.gov (United States)

    Owen, Yvonne; Amory, Jonathan R

    2011-01-01

    Traditional techniques used to capture New World monkeys, such as net capture, can induce high levels of acute stress detrimental to welfare. Alternatively, training nonhuman animals via operant conditioning to voluntarily participate in husbandry and/or veterinary practices is accepted as a humane process that can reduce stress and improve welfare. This study details the use of operant conditioning using positive reinforcement training (PRT) and target training to train a family of 5 captive red-bellied tamarins (Saguinus labiatus) in a wildlife park to voluntarily enter a transportation box and remain calm for 1 min after 54 training sessions. Observations of 2 unrelated net-capture processes provided measures of locomotion and vocalizations as indicators of stress behavior that were compared with those of the trained tamarins. Net-captured monkeys exhibited rapid erratic locomotion and emitted long, high-frequency vocalizations during capture whereas the trained tamarins exhibited minimal locomotion and emitted only 4 brief vocalizations (root mean square 35 dB) during capture. This indicates that the use of PRT considerably reduced potential for stress and improved welfare during the capture and containment of the tamarins. Copyright © Taylor & Francis Group, LLC

  3. Correlation of Growth and Surface Properties of Poly(\\(p\\-xylylenes to  Reaction Conditions

    Directory of Open Access Journals (Sweden)

    Andreas Reichel

    2015-05-01

    Full Text Available Parylene, a non-critical, non-toxic layer material, which is not only a candidate for low-\\(K\\ dielectrics, but also well suited for long-term applications in the human body, has been deposited by (plasma-enhanced chemical vapor deposition of the monomeric species. To that end, a specially-designed reactor exhibiting a cracker tube at its entrance, which serves as the upstream control, and a cooling trap in front of the downstream control has been applied. The process of polymerization has been traced and is explained by evaporating the dimeric species followed by dissociation in the cracker at elevated temperatures and, eventually, to the coating of the polymeric film in terms of thermodynamics. Alternatively, the process of dissociation has been accomplished applying a microwave plasma. In both cases, the monomerization is controlled by mass spectrometry. The window for surface polymerization could be clearly defined in terms of a factor of dilution by an inert gas for the chemical vapor deposition (CVD case and in the case of plasma-enhanced chemical vapor deposition (PECVD, additionally by the power density. The characterization of the layer parameters has been carried out by several analytical tools: scanning electron microscopy and atomic force microscopy to determine the surface roughness and density and depth of voids in the film, which influence the layer capacitance and deteriorate the breakdown voltage, a bulk property. The main issue is the conduct against liquids between the two borders' hydrophilic and hydrophobic conduct, but also the super-hydrophobic character, which is the condition for the Lotus effect. The surface tension has been evaluated by contact angle measurements. Fourier-transform infrared spectroscopy has proven the conservation of all of the functional groups during polymerization.

  4. Combined chemical and EIS study of the reaction of zinc coatings under alkaline conditions

    International Nuclear Information System (INIS)

    Walkner, Sarah; Hassel, Achim Walter

    2014-01-01

    Graphical abstract: - Highlights: • An electrochemical unit for automatic EIS and pH modulation is used. • ZnMg2Al2 and ZnAl53 are studied in alkaline solutions. • Amount of consumed sodium hydroxide allows following hydroxide formation and film thickness. • Cross sections of 13 μm show excellent agreement with consumed hydroxide. • ZnAl53 consumes more hydroxide due to soluble aluminate formation. - Abstract: Two different zinc coatings of composition ZnMg2Al2 (Zn + 2 wt.% Mg + 2 wt.% Al) and ZnAl53 (Zn + 53 wt.% Al) were investigated in aqueous solution at pH 12.0 with a novel setup, the so-called impedance titrator. This device is able to perform electrochemical measurements including, but not limited to, impedance spectroscopy in dependency of different pH-values. The setup allows holding the pH-value with a precision of at least 0.05 by dosing the required amount of titrating agent to the system. If the alkaline pH region is investigated, hydroxide ions are consumed in the course of passive layer formation. The amount of consumed hydroxide allows to quantitatively follow the formation of the hydroxide film and its thickness. Cross section SEM shows an excellent agreement of 13 μm after 7 h for ZnMg2Al2. At a constant pH value, the hydroxide concentration is constant and film formation is well defined and kinetically characterised. The consumption of hydroxide by the ZnAl53 coating is higher resulting from the solubility of the Al as aluminate under alkaline conditions. The composition of the precipitates contains less than 3 wt.% of Al. The observed processes and the formation of corrosion products are recorded and differences in the behaviour of the two coatings are discussed

  5. Employment of single-diode model to elucidate the variations in photovoltaic parameters under different electrical and thermal conditions.

    Directory of Open Access Journals (Sweden)

    Fahmi F Muhammad

    Full Text Available In this research work, numerical simulations are performed to correlate the photovoltaic parameters with various internal and external factors influencing the performance of solar cells. Single-diode modeling approach is utilized for this purpose and theoretical investigations are compared with the reported experimental evidences for organic and inorganic solar cells at various electrical and thermal conditions. Electrical parameters include parasitic resistances (Rs and Rp and ideality factor (n, while thermal parameters can be defined by the cells temperature (T. A comprehensive analysis concerning broad spectral variations in the short circuit current (Isc, open circuit voltage (Voc, fill factor (FF and efficiency (η is presented and discussed. It was generally concluded that there exists a good agreement between the simulated results and experimental findings. Nevertheless, the controversial consequence of temperature impact on the performance of organic solar cells necessitates the development of a complementary model which is capable of well simulating the temperature impact on these devices performance.

  6. Quantitative changes in proteins responsible for flavonoid and anthocyanin biosynthesis in strawberry fruit at different ripening stages: A targeted quantitative proteomic investigation employing multiple reaction monitoring.

    Science.gov (United States)

    Song, Jun; Du, Lina; Li, Li; Kalt, Wilhelmina; Palmer, Leslie Campbell; Fillmore, Sherry; Zhang, Ying; Zhang, ZhaoQi; Li, XiHong

    2015-06-03

    To better understand the regulation of flavonoid and anthocyanin biosynthesis, a targeted quantitative proteomic investigation employing LC-MS with multiple reaction monitoring was conducted on two strawberry cultivars at three ripening stages. This quantitative proteomic workflow was improved through an OFFGEL electrophoresis to fractionate peptides from total protein digests. A total of 154 peptide transitions from 47 peptides covering 21 proteins and isoforms related to anthocyanin biosynthesis were investigated. The normalized protein abundance, which was measured using isotopically-labeled standards, was significantly changed concurrently with increased anthocyanin content and advanced fruit maturity. The protein abundance of phenylalanine ammonia-lyase; anthocyanidin synthase, chalcone isomerase; flavanone 3-hydroxylase; dihydroflavonol 4-reductase, UDP-glucose:flavonoid-3-O-glucosyltransferase, cytochrome c and cytochrome C oxidase subunit 2, was all significantly increased in fruit of more advanced ripeness. An interaction between cultivar and maturity was also shown with respect to chalcone isomerase. The good correlation between protein abundance and anthocyanin content suggested that a metabolic control point may exist for anthocyanin biosynthesis. This research provides insights into the process of anthocyanin formation in strawberry fruit at the level of protein concentration and reveals possible candidates in the regulation of anthocyanin formation during fruit ripening. To gain insight into the molecular mechanisms contributing to flavonoids and anthocyanin biosynthesis and regulation of strawberry fruit during ripening is challenging due to limited molecular biology tools and established hypothesis. Our targeted proteomic approach employing LC-MS/MS analysis and MRM technique to quantify proteins in relation to flavonoids and anthocyanin biosynthesis and regulation in strawberry fruit during fruit ripening is novel. The identification of peptides

  7. Gender and Ageing at Work in Chile: Employment, Working Conditions, Work-Life Balance and Health of Men and Women in an Ageing Workforce.

    Science.gov (United States)

    Vives, Alejandra; Gray, Nora; González, Francisca; Molina, Agustín

    2018-04-18

    In Chile, working after retirement age has grown substantially over the last years. This, in addition to the country's current discussion about extending retirement age, motivates the need of generating evidence on the occupational health and safety of the working old, with a special focus on women, who are critically disadvantaged in Chile's labour market. The objective of this paper is to describe and compare the ageing workforce of women and men in Chile in terms of labour market participation, employment and working conditions, work-life balance, and health. The social determinants of health and employment sustainability frameworks guide this study. Cross-sectional data from three publicly available sources: the Chilean Labour Force Survey, NENE (2010); the first Chilean Employment and working conditions survey, ENETS (2009-2010) and the second National Health Survey, ENS (2009). Participation rates and employment conditions (NENE and ENETS), working conditions, occupational health and work-life balance (ENETS) and chronic health conditions (ENS) were described by 5-year age groups separately for women and men. Descriptions cover all age groups in order to identify trends and patterns characteristic of older workers. Rates of occupation decrease sharply after age 54 in women and 59 in men. Ageing women and men who continue to work are more likely to be in own-account (self-employed) work than younger workers; in the case of women, in households as domestic workers, and men, in agriculture. Social protection and workplace rights are markedly reduced in older workers. Part-time work increases from the age of 50 onwards, especially among women, but average working hours do not decrease under 30 h a week for either women or men. Interestingly, between ages 60 and 64, there is a peak increase of day and night shift-work among women, which co-occurs with a peak in domestic work, possibly corresponding to women working as caretakers of elderly people. Several

  8. Effect of Drying Conditions on the Catalytic Performance, Structure, and Reaction Rates over the Fe-Co-Mn/MgO Catalyst for Production of Light Olefins

    Directory of Open Access Journals (Sweden)

    Majid Abdouss

    2018-01-01

    How to Cite: Abdouss, M., Arsalanfar, M., Mirzaei, N., Zamani, Y. (2018. Effect of Drying Conditions on the Catalytic Performance, Structure, and Reaction Rates over the Fe-Co-Mn/MgO Catalyst for Production of Light Olefins. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (1: 97-112 (doi:10.9767/bcrec.13.1.1222.97-112

  9. Social Informatics: Natural Tools for Students' Information Training in The Conditions of Embodied and Mental Approaches Being Employed

    Directory of Open Access Journals (Sweden)

    Daria Barkhatova

    2017-09-01

    Full Text Available The relevance of the problem under study is due to the society's requirements for the quality information training of a personality which is oriented to forming the solid fundamental knowledge as well as to developing the cognitive capacities that are needed for solving mental tasks. With regard to this, the paper is aimed at finding out the opportunities of applying the natural tools in information training of students from the standpoints of embodied and mental approaches. The main idea of these is integrated studying of an object, beginning with learning it in an "embodied" way and finishing with abstract models formed in the human memory. The leading approach to the research is the integrated one taking into account the psychological and pedagogical, didactic and methodological constituents. It allows identifying the psychological and pedagogical conditions of application of natural tools as well as the possible ways of their use. The authors describe models of natural tools of computer science training in individual sections of the school course as the main results. The materials of the paper are of practical value in methods of teaching computer science to students at various stages of education.

  10. Elimination of carbon vacancies in 4H-SiC employing thermodynamic equilibrium conditions at moderate temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Ayedh, H. M.; Svensson, B. G. [University of Oslo, Department of Physics/Center for Materials Science and Nanotechnology, P.O. Box 1048 Blindern, N-0316 Oslo (Norway); Nipoti, R. [Consiglio Nazionale delle Ricerche, Istituto di Microelettronica e Microsistemi, Sezione di Bologna (CNR-IMM of Bologna), I-40129 Bologna (Italy); Hallén, A. [Royal Institute of Technology, School of Information and Communication Technology (ICT), SE-164 40 Kista-Stockholm (Sweden)

    2015-12-21

    The carbon vacancy (V{sub C}) is a major point defect in high-purity 4H-SiC epitaxial layers limiting the minority charge carrier lifetime. In layers grown by chemical vapor deposition techniques, the V{sub C} concentration is typically in the range of 10{sup 12 }cm{sup −3}, and after device processing at temperatures approaching 2000 °C, it can be enhanced by several orders of magnitude. In the present study, both as-grown layers and a high-temperature processed one have been annealed at 1500 °C and the V{sub C} concentration is demonstrated to be strongly reduced, exhibiting a value of only a few times 10{sup 11 }cm{sup −3} as determined by deep-level transient spectroscopy measurements. The value is reached already after annealing times on the order of 1 h and is evidenced to reflect thermodynamic equilibrium under C-rich ambient conditions. The physical processes controlling the kinetics for establishment of the V{sub C} equilibrium are estimated to have an activation energy below ∼3 eV and both in-diffusion of carbon interstitials and out-diffusion of V{sub C}'s are discussed as candidates. This concept of V{sub C} elimination is flexible and readily integrated in a materials and device processing sequence.

  11. Combination of Deep Recurrent Neural Networks and Conditional Random Fields for Extracting Adverse Drug Reactions from User Reviews.

    Science.gov (United States)

    Tutubalina, Elena; Nikolenko, Sergey

    2017-01-01

    Adverse drug reactions (ADRs) are an essential part of the analysis of drug use, measuring drug use benefits, and making policy decisions. Traditional channels for identifying ADRs are reliable but very slow and only produce a small amount of data. Text reviews, either on specialized web sites or in general-purpose social networks, may lead to a data source of unprecedented size, but identifying ADRs in free-form text is a challenging natural language processing problem. In this work, we propose a novel model for this problem, uniting recurrent neural architectures and conditional random fields. We evaluate our model with a comprehensive experimental study, showing improvements over state-of-the-art methods of ADR extraction.

  12. Combination of Deep Recurrent Neural Networks and Conditional Random Fields for Extracting Adverse Drug Reactions from User Reviews

    Directory of Open Access Journals (Sweden)

    Elena Tutubalina

    2017-01-01

    Full Text Available Adverse drug reactions (ADRs are an essential part of the analysis of drug use, measuring drug use benefits, and making policy decisions. Traditional channels for identifying ADRs are reliable but very slow and only produce a small amount of data. Text reviews, either on specialized web sites or in general-purpose social networks, may lead to a data source of unprecedented size, but identifying ADRs in free-form text is a challenging natural language processing problem. In this work, we propose a novel model for this problem, uniting recurrent neural architectures and conditional random fields. We evaluate our model with a comprehensive experimental study, showing improvements over state-of-the-art methods of ADR extraction.

  13. Algorithm for Fast and Efficient Detection and Reaction to Angle Instability Conditions Using Phasor Measurement Unit Data

    Directory of Open Access Journals (Sweden)

    Igor Ivanković

    2018-03-01

    Full Text Available In wide area monitoring, protection, and control (WAMPAC systems, angle stability of transmission network is monitored using data from phasor measurement units (PMU placed on transmission lines. Based on this PMU data stream advanced algorithm for out-of-step condition detection and early warning issuing is developed. The algorithm based on theoretical background described in this paper is backed up by the data and results from corresponding simulations done in Matlab environment. Presented results aim to provide the insights of the potential benefits, such as fast and efficient detection and reaction to angle instability, this algorithm can have on the improvement of the power system protection. Accordingly, suggestion is given how the developed algorithm can be implemented in protection segments of the WAMPAC systems in the transmission system operator control centers.

  14. Reaction kinetics of hydrazine neutralization in steam generator wet lay-up solution: Identifying optimal degradation conditions

    International Nuclear Information System (INIS)

    Schildermans, Kim; Lecocq, Raphael; Girasa, Emmanuel

    2012-09-01

    During a nuclear power plant outage, hydrazine is used as an oxygen scavenger in the steam generator lay-up solution. However, due to the carcinogenic effects of hydrazine, more stringent discharge limits are or will be imposed in the environmental permits. Hydrazine discharge could even be prohibited. Consequently, hydrazine alternatives or hydrazine degradation before discharge is needed. This paper presents the laboratory tests performed to characterize the reaction kinetics of hydrazine neutralization using bleach or hydrogen peroxide, catalyzed with either copper sulfate (CuSO 4 ) or potassium permanganate (KMnO 4 ). The tests are performed on two standard steam generator lay-up solutions based on different pH control agents: ammonia or ethanolamine. Different neutralization conditions are tested by varying temperature, oxidant addition, and catalyst concentration, among others, in order to identify the optimal parameters for hydrazine neutralization in a steam generator wet lay-up solution. (authors)

  15. Common symptoms in middle aged women: their relation to employment status, psychosocial work conditions and social support in a Swedish setting.

    Science.gov (United States)

    Krantz, G; Ostergren, P O

    2000-03-01

    Over the past few decades there has been a growing interest among researchers, in women's overall life circumstances and their relation to women's health status. For example, paid employment has been considered an important part of women's living conditions in Western societies as the number of women entering the labour market has grown constantly over the past decades. When comparing men's and women's health, one of the most consistent findings is a higher rate of symptoms among women. The most commonly reported symptoms in women are depressive symptoms, symptoms of bodily tension and chronic pain from muscles and joints. The aim of this study was to investigate whether socioeconomic factors, employment status, psychosocial work conditions and social network/support are associated with middle aged women's health status in terms of common symptoms. A mailed questionnaire was used in a cross sectional design assessing socioeconomic factors, employment status, psychosocial work conditions according to the demand/control model, social network/support and an index based on the 15 most frequent symptoms presented by middle aged women when seeking health care. A rural community with 13,200 inhabitants in the western part of Sweden. Women were randomly selected from the general population in the study area, 40 to 50 years of age. The response rate was 81.7 per cent. Women who were non-employed had a significantly increased odds of a high level of common symptoms (OR = 2.82; 95% confidence intervals 1.69, 4.70), as well as women exposed to job strain (OR = 3.27; 1.92, 5.57), independently of the level of social network/support. Furthermore, exposure to low social support, low social anchorage or low social participation independently showed significantly increased odds of a high level of common symptoms (OR = 2.75; 1.71, 4.42; OR = 2.91; 1.81, 4.69 and OR = 1.69; 1.10, 2.61, respectively). Work related factors, such as non-employment and job strain, and circumstances

  16. Fischer-Tropsch diesel production over calcium-promoted Co/alumina catalyst: Effect of reaction conditions

    Energy Technology Data Exchange (ETDEWEB)

    A.R. de la Osa; A. De Lucas; A. Romero; J.L. Valverde; P. Sanchez [University of Castilla-La Mancha, Ciudad Real (Spain). Chemical Engineering Department

    2011-05-15

    The effects of reaction conditions on the Fischer-Tropsch activity and product distribution of an alkali-earth metal promoted cobalt based catalyst were studied. The influence of the promoter on the reducibility and cobalt particle size was studied by different techniques, including N{sub 2} adsorption, X-ray diffraction, temperature-programmed reduction, temperature-programmed desorption and acid-base titrations. Experiments were carried out on a bench-scale fixed bed reactor and catalysts were prepared by incipient wetness impregnation. It was observed that addition of a small amount of calcium oxide as a promoter (0.6 wt.%) improved the cobalt oxide reducibility and reduced the formation of cobalt-aluminate species. A positive correlation between basicity and particle size was observed. In terms of FTS results, CO conversion and C{sub 5}{sup +} selectivity were found to be enhanced by the addition of this promoter. It was important to note that the addition of calcium shifted the distribution to mainly C{sub 16}-C{sub 18} hydrocarbons fraction, which could be greatly considered for a diesel formulation. Furthermore, the variation of the reaction conditions seemed to influence product distribution in a lesser extent than unpromoted catalyst. Also, a displacement of hydrocarbon distribution to higher molecular weight with decreasing space velocity and temperature was observed. Moreover, the addition of calcium to the cobalt based catalyst was found to greatly maintain selectivity to C{sub 5}{sup +} for a wide range of H{sub 2}/CO molar ratios. 60 refs., 10 figs., 5 tabs.

  17. Becoming Self-Employed.

    Science.gov (United States)

    Lee, Grant; Cochran, Larry

    1997-01-01

    Explored how persons become self-employed. In critical incident interviews with five self-employed persons the critical events that assisted or hindered progress toward self-employment were listed in chronological order. In general, becoming self-employed involved establishing conditions of action that enhanced a sense of agency, thus enabling…

  18. Contribution of Histidine and Lysine to the Generation of Volatile Compounds in Jinhua Ham Exposed to Ripening Conditions Via Maillard Reaction.

    Science.gov (United States)

    Zhu, Chao-Zhi; Zhao, Jing-Li; Tian, Wei; Liu, Yan-Xia; Li, Miao-Yun; Zhao, Gai-Ming

    2018-01-01

    To evaluate the role of Maillard reactions in the generation of flavor compounds in Jinhua ham, the reactions of glucose and ethanal with histidine and lysine, respectively, were studied by simulating the ripening conditions of Jinhua ham. The volatile products produced were analyzed using solid phase microextraction-gas chromatography/mass spectrometry. The results showed that 8 volatile compounds were generated by the reaction of glucose and histidine and 10 volatile compounds were generated by the reaction of glucose and lysine. Reactions of ethanal with lysine and with histidine both generated 31 volatile compounds that contributed to the flavor of Jinhua ham. This indicates that histidine and lysine related to Maillard reactions possibly play important roles in the generation of the unique flavor compounds in Jinhua ham. This research demonstrates that free amino acids participate in the generation of volatile compounds from Jinhua ham via the Maillard reaction and provides a basic mechanism to explain flavor formation in Jinhua ham. Jinhua ham is a well-known traditional Chinese dry-cured meat product. However, the formation of the compounds comprising its special flavor is not well understood. Our results indicate that Maillard reactions occur in Jinhua ham under ripening conditions. This work illustrates the contribution of Maillard reactions to the flavor of Jinhua ham. © 2017 Institute of Food Technologists®.

  19. Loss of Functional Photosystem II Reaction Centres in Zooxanthellae of Corals Exposed to Bleaching Conditions: Using Fluorescence Rise Kinetics.

    Science.gov (United States)

    Hill, R; Larkum, A W D; Frankart, C; Kühl, M; Ralph, P J

    2004-01-01

    Mass coral bleaching is linked to elevated sea surface temperatures, 1-2 degrees C above average, during periods of intense light. These conditions induce the expulsion of zooxanthellae from the coral host in response to photosynthetic damage in the algal symbionts. The mechanism that triggers this release has not been clearly established and to further our knowledge of this process, fluorescence rise kinetics have been studied for the first time. Corals that were exposed to elevated temperature (33 degrees C) and light (280 mumol photons m(-2) s(-1)), showed distinct changes in the fast polyphasic induction of chlorophyll-a fluorescence, indicating biophysical changes in the photochemical processes. The fluorescence rise over the first 2000ms was monitored in three species of corals for up to 8 h, with a PEA fluorometer and an imaging-PAM. Pocillopora damicornis showed the least impact on photosynthetic apparatus, while Acropora nobilis was the most sensitive, with Cyphastrea serailia intermediate between the other two species. A. nobilis showed a remarkable capacity for recovery from bleaching conditions. For all three species, a steady decline in the slope of the initial rise and the height of the J-transient was observed, indicating the loss of functional Photosystem II (PS II) centres under elevated-temperature conditions. A significant loss of PS II centres was confirmed by a decline in photochemical quenching when exposed to bleaching stress. Non-photochemical quenching was identified as a significant mechanism for dissipating excess energy as heat under the bleaching conditions. Photophosphorylation could explain this decline in PS II activity. State transitions, a component of non-photochemical quenching, was a probable cause of the high non-photochemical quenching during bleaching and this mechanism is associated with the phosphorylation-induced dissociation of the light harvesting complexes from the PS II reaction centres. This reversible process may

  20. Growth of enstatite and enstatite-forsterite reaction rims under wet conditions during isostatic annealing and triaxial deformation

    Science.gov (United States)

    Helpa, Vanessa; Rybacki, Erik; Dresen, Georg

    2017-04-01

    To investigate the influence of differential stress and microstructure on reaction rates, we studied experimentally enstatite-forsterite double rim formation in between periclase and quartz according to the reaction MgO +

  1. Concentration of eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA of Asian catfish oil by urea complexation: optimization of reaction conditions

    Directory of Open Access Journals (Sweden)

    Pornpisanu Thammapat

    2016-04-01

    Full Text Available Optimization of the concentrating conditions of eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA extracted from Asian catfish oil was studied to obtain a maximum concentration. The crude fish oil was extracted from the belly flap and adipose tissue of Asian catfish, and the extracted oil was used as fresh crude oil. The EPA and DHA were concentrated by the urea complexation method. A hexagonal rotatable design was applied to examine the effects of crystallization temperature and urea-to-fatty acid ratio on the total content of EPA and DHA (Y1 and the liquid recovery yield (Y2 . The second order polynomial regression models for Y1 and Y2 were employed to generate the response surfaces. Under the optimum conditions of -20 °C and a urea-to-fatty acid ratio of 4 (w/w, the total concentration of EPA and DHA could be increased by up to 88%, while a liquid recovery yield of 26% was obtained.

  2. EFFECT OF THE REACTION CONDITIONS OVER THE YIELD AND PROPERTIES OF METHYLCELLULOSE OBTAINED FROM PINUS RADIATA KRAFT BLEACHED CELLULOSE

    OpenAIRE

    TAPIA, C.; SAPAG-HAGAR, J.; ANDRADE, C.T.; HASSÓN, J.; VALENZUELA, F.; BASUALTO, C.

    2002-01-01

    Kraft bleached cellulose from Pinus radiata was submitted to methylation reactions in heterogeneous media. After activation with 29% (w/w) NaOH solution, methylation reactions were carried out both with dimethyl sulfate (DMS) and methyl iodide (MI). The effects of the pressing ratio, reaction time and type of methylation agent were studied. The better yields were obtained with dimethylsulphate and the pressing ratio and reaction time were not signficant over the yield. Methylcellulose (MC) of...

  3. Quantum dynamics of the Eley-Rideal hydrogen formation reaction on graphite at typical interstellar cloud conditions.

    Science.gov (United States)

    Casolo, Simone; Martinazzo, Rocco; Bonfanti, Matteo; Tantardini, Gian Franco

    2009-12-31

    Eley-Rideal formation of hydrogen molecules on graphite, as well as competing collision induced processes, are investigated quantum dynamically at typical interstellar cloud conditions, focusing in particular on gas-phase temperatures below 100 K, where much of the chemistry of the so-called diffuse clouds takes place on the surface of bare carbonaceous dust grains. Collisions of gas-phase hydrogen atoms with both chemisorbed and physisorbed species are considered using available potential energy surfaces (Sha et al., J. Chem. Phys.2002 116, 7158), and state-to-state, energy-resolved cross sections are computed for a number of initial vibrational states of the hydrogen atoms bound to the surface. Results show that (i) product molecules are internally hot in both cases, with vibrational distributions sharply peaked around few (one or two) vibrational levels, and (ii) cross sections for chemisorbed species are 2-3x smaller than those for physisorbed ones. In particular, we find that H(2) formation cross sections out of chemically bound species decrease steadily when the temperature drops below approximately 1000 K, and this is likely due to a quantum reflection phenomenon. This suggests that such Eley-Rideal reaction is all but efficient in the relevant gas-phase temperature range, even when gas-phase H atoms happen to chemisorb barrierless to the surface as observed, e.g., for forming so-called para dimers. Comparison with results from classical trajectory calculations highlights the need of a quantum description of the dynamics in the astrophysically relevant energy range, whereas preliminary results of an extensive first-principles investigation of the reaction energetics reveal the importance of the adopted substrate model.

  4. Effects of network dissolution changes on pore-to-core upscaled reaction rates for kaolinite and anorthite reactions under acidic conditions

    KAUST Repository

    Kim, Daesang; Lindquist, W. Brent

    2013-01-01

    new connections. The computed changes were based upon a mineral map from an X-ray computed tomography image of a sandstone core. We studied the effect of these changes on upscaled (pore-scale to core-scale) reaction rates and compared against

  5. Synthesis of different-sized silver nanoparticles by simply varying reaction conditions with leaf extracts of Bauhinia variegata L.

    Science.gov (United States)

    Kumar, V; Yadav, S K

    2012-03-01

    Green synthesis of nanoparticles is one of the crucial requirements in today's climate change scenario all over the world. In view of this, leaf extract (LE) of Bauhinia variegata L. possessing strong antidiabetic and antibacterial properties has been used to synthesise silver nanoparticles (SNP) in a controlled manner. Various-sized SNP (20-120 nm) were synthesised by varying incubation temperature, silver nitrate and LE concentrations. The rate of SNP synthesis and their size increased with increase in AgNO(3) concentration up to 4 mM. With increase in LE concentration, size and aggregation of SNP was increased. The size and aggregation of SNP were also increased at temperatures above and below 40°C. This has suggested that size and dispersion of SNP can be controlled by varying reaction components and conditions. Polarity-based fractionation of B. variegata LE has suggested that only water-soluble fraction is responsible for SNP synthesis. Fourier transform infrared spectroscopy analysis revealed the attachment of polyphenolic and carbohydrate moieties to SNP. The synthesised SNPs were found stable in double distilled water, BSA and phosphate buffer (pH 7.4). On the contrary, incubation of SNP with NaCl induced aggregation. This suggests the safe use of SNP for various in vivo applications.

  6. Structural Evolution under Reaction Conditions of Supported (NH43HPMo11VO40 Catalysts for the Selective Oxidation of Isobutane

    Directory of Open Access Journals (Sweden)

    Fangli Jing

    2015-03-01

    Full Text Available When using heteropolycompounds in the selective oxidation of isobutane to methacrolein and methacrylic acid, both the keeping of the primary structure (Keggin units and the presence of acidic sites are necessary to obtain the desired products. The structural evolution of supported (NH43HPMo11VO40 (APMV catalysts under preliminary thermal oxidizing and reducing treatments was investigated. Various techniques, such as TGA/DTG (Thermo-Gravimetric Analysis/Derivative Thermo-Gravimetry, H2-TPR (Temperature Programed Reduction, in situ XRD (X-Ray Diffraction and XPS (X-ray Photoelectron Spectroscopy, were applied. It was clearly evidenced that the thermal stability and the reducibility of the Keggin units are improved by supporting 40% APMV active phase on Cs3PMo12O40 (CPM. The partial degradation of APMV takes place depending on temperature and reaction conditions. The decomposition of ammonium cations (releasing NH3 leads to the formation of vacancies favoring cationic exchanges between vanadium coming from the active phase and cesium coming from the support. In addition, the vanadium expelled from the Keggin structure is further reduced to V4+, species, which contributes (with Mo5+ to activate isobutane. The increase in reducibility of the supported catalyst is assumed to improve the catalytic performance in comparison with those of unsupported APMV.

  7. Gender role stereotype and poor working condition pose obstacles for female doctors to stay in full-time employment: alumnae survey from two private medical schools in Japan.

    Science.gov (United States)

    Izumi, Miki; Nomura, Kyoko; Higaki, Yuko; Akaishi, Yu; Seki, Masayasu; Kobayashi, Shizuko; Komoda, Takayuki; Otaki, Junji

    2013-03-01

    The shortage of physicians has become a serious problem in Japan. It has been pointed out that an increase in the number of female doctors may contribute to the aggravation of this shortage because it is known that women work fewer hours than male doctors. Here, we investigated how many female doctors had ever resigned from a full-time position, and elucidated the reasons why female doctors find it difficult to stay in full-time employment. An alumnae survey of 2 private medical schools was conducted in 2007. A self-administered questionnaire was sent to 1423 graduates and 711 responded with informed consent (response rate, 50%; mean age, 39 years). Overall, 55% of the respondents had previously resigned from full-time employment, of which 90% resigned within 10 years of graduating from medical school. The difficulty in balancing work, childbirth and child rearing (45%) were the top 2 reasons for resignation, followed by physical problems (12%) and long working hours (8%). Among those who resigned, only 33% returned to full-time employment. Women who had at least 1 child were only 30% of those who had never resigned and 84% of those who had previously resigned. The majority of study subjects, regardless of experience of resignation (88%), agreed that women should continue to work even after childbirth. In conclusion, the results of this study suggested that many female doctors resigned from a full-time position within 10 years of graduating from medical school, largely because of the gender role stereotype and poor working conditions.

  8. Preferential processing of tactile events under conditions of divided attention: Effects of divided attention on reaction time

    OpenAIRE

    Hanson, James V. M.; Whitaker, David; Heron, James

    2009-01-01

    Differences in transduction and transmission latencies of visual, auditory and tactile events cause corresponding differences in simple reaction time. As reaction time is usually measured in unimodal blocks, it is unclear whether such latency differences also apply when observers monitor multiple sensory channels. We investigate this by comparing reaction time when attention is focussed on a single modality, and when attention is divided between multiple modalities. Results show that tactile ...

  9. Liquid-assisted grinding and ion pairing regulates percentage conversion and diastereoselectivity of the Wittig reaction under mechanochemical conditions.

    Science.gov (United States)

    Denlinger, Kendra Leahy; Ortiz-Trankina, Lianna; Carr, Preston; Benson, Kingsley; Waddell, Daniel C; Mack, James

    2018-01-01

    Mechanochemistry is maturing as a discipline and continuing to grow, so it is important to continue understanding the rules governing the system. In a mechanochemical reaction, the reactants are added into a vessel along with one or more grinding balls and the vessel is shaken at high speeds to facilitate a chemical reaction. The dielectric constant of the solvent used in liquid-assisted grinding (LAG) and properly chosen counter-ion pairing increases the percentage conversion of stilbenes in a mechanochemical Wittig reaction. Utilizing stepwise addition/evaporation of ethanol in liquid-assisted grinding also allows for the tuning of the diastereoselectivity in the Wittig reaction.

  10. Measurement of {sup 27}Al(γ,2pn){sup 24}Na Reaction Cross-sections with 55 -, 60 -, 65 - MeV Bremsstrahlung Employing MCNPX Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Shin, S. G.; Kye, Y.; Cho, M. H. [POSTECH, Pohang (Korea, Republic of); Namkung, W. [Pohang Accelerator Laboratory, Pohang (Korea, Republic of); KIm, G. N.; Kim, K. [Kyungpook National Univ., Daegu (Korea, Republic of); Lee, M. W.; Kang, Y. R. [Dongnam Inst. Of Radiological and Medical Science, Busan (Korea, Republic of)

    2014-05-15

    Aluminum is used for monitoring the photon flux. The photon flux during the activation can be measured by substituting the {sup 27}Al(γ,2pn){sup 24}Na reaction cross-section induced by bremsstrahlung to reactivity equation. Therefore, if this cross-section is more accurate, gamma-ray flux can be measure more accurately. In this work, the {sup 27}Al(γ,2pn){sup 24}Na reaction cross-sections induced by 55 - 65 MeV bremsstrahlung were measured by activation technique at the Pohang Neutron Facility (PNF) which has produced the nuclear data using Time-Of-Flight method and activation technique. In order to get the photon flux, MCNPX was used. These measurement values were compared with the data of Meyer et al (1968)

  11. [Risk of certain obstetric pathologies in women employed in working conditions non-complying with the current legal status on work load and working conditions appropriate for pregnant women].

    Science.gov (United States)

    Makowiec-Dabrowska, Teresa; Hanke, Wojciech; Sobala, Wojciech; Radwan-Włodarczyk, Zyta; Koszada-Włodarczyk, Wiesława

    2003-01-01

    The aim of the study was to define the incidence of prematurity and small-for-gestational age (SGA) infants in occupationally involved pregnant women, and to find out how far working conditions departing from binding regulations contribute to the risk of the development of these pathologies. The study was carried out on a representative sample of 3050 women employed for longer than one week during pregnancy in the Łódź district. An interview conducted with the subjects few days after delivery was the source of information about working conditions. The obtained information was compared with the real situation in about 10% of randomly selected workposts. A high level of consistence was observed. The study revealed that almost 60% of women work in conditions, which do not comply with the Labor Code provisions setting working conditions permissible for pregnant women. In the study group, 4.68% of prematurity and 6.15% of SGA were recorded. A 66% excess in the risk of delivering SGA infants in case of at least one factor not complying with regulations was revealed. The excess was growing with the increased number of departures from regulations and continuation of employment during pregnancy. It was estimated that the number of SGA cases would decrease by 28% if the working conditions would have met the requirements. A prolonged time of work, local vibration for > 4h/shift, forced work pace, excessive effort and forced body position during the work performance contributed mostly to the risk of pathology. Interestingly, the risk of premature delivery was lower by about 40% in women working in unsatisfactory conditions, which is attributed to termination of work immediately after the occurrence of pregnancy-threatening symptoms. Only those women whose pregnancy was not threatened with pathology could continue their work. The study revealed a quite large number of workplaces not complying with regulations on working conditions permissible for pregnant women. Therefore

  12. The Effect of Mg Addition and Manufacturing Conditions on the Interfacial Reactions between Al and CNT in Al-CNT Pellets

    International Nuclear Information System (INIS)

    Lim, Jung-Kyu; Choi, Soon-Yool; Choe, Kyong-Hwan; Cho, Gue-Serb; Kim, Sang-Sub

    2013-01-01

    In the present study, Al-CNT pellets were investigated to understand the effect of Mg addition and manufacturing conditions on the interfacial reactions between Al and CNTs in Al-CNT pellets. The pellets were heated and held at 700 °C and 800 °C for 2 hours under nitrogen (N_2) atmosphere. To confirm the reactions between Al and CNT in the pellets under different manufacturing conditions, the microstructures were observed by optical microscopy (OM) and field emission scanning electro microscopy (FESEM). And, the composition and reaction phases were analyzed by energy dispersive X-ray spectroscory (EDXS) and X-ray diffractometry (XRD). The presence of oxidation products and Mg on the surface of Al powder in the pellets appeared to prevent the formation of Al_4C_3. But, Al_4C_3 reaction products were increased due to the high temperature of 800 °C, which produced a high amount of reduced aluminium and increased the reaction areas between Al and CNT. The Al-CNT pellets compacted under air atmosphere prohibited the reaction between Al and CNT because of the high amount of oxidation products, such as MgO and MgAl_2O_4.

  13. Quality of employment conditions and employment relations in Europe: a report based on the fifth European Working Conditions Survey = Ποιότητα των συνθηκών απασχόλησης και των σχέσεων απασχόλησης στην Ευρώπη: περίληψη

    OpenAIRE

    Benach, Joan; Vanroelen, Christophe; Vives, Alejandra; De Witte, Hans; Puig-Barrachina, Vanessa; Belvis-Costes, Francesc; Ferrer-Armengou, Olga; Van Aerden, Karen

    2013-01-01

    This study aims to provide an in-depth analysis of the quality of employment conditions and relations as experienced by the European employed workforce. Employment conditions have to do with agreements between employees and their employer about the organisation of employment in terms of issues such as contractual forms, rewards, working hours and training. Employment relations refer to the way all stakeholders at work interact with each other, both in a formal (such as collective bargaining p...

  14. Proof of existence of global solutions for m-component reaction-diffusion systems with mixed boundary conditions via the Lyapunov functional method

    International Nuclear Information System (INIS)

    Abdelmalek, Salem; Kouachi, Said

    2007-01-01

    To prove global existence for solutions of m-component reaction-diffusion systems presents fundamental difficulties in the case in which some components of the system satisfy Neumann boundary conditions while others satisfy nonhomogeneous Dirichlet boundary conditions and nonhomogeneous Robin boundary conditions. The purpose of this paper is to prove the existence of a global solution using a single inequality for the polynomial growth condition of the reaction terms. Our technique is based on the construction of polynomial functionals. This result generalizes those obtained recently by Kouachi et al (at press), Kouachi (2002 Electron. J. Diff. Eqns 2002 1), Kouachi (2001 Electron. J. Diff. Eqns 2001 1) and independently by Malham and Xin (1998 Commun. Math. Phys. 193 287)

  15. Determination of the in vivo NAD:NADH ratio in Saccharomyces cerevisiae under anaerobic conditions, using alcohol dehydrogenase as sensor reaction.

    Science.gov (United States)

    Bekers, K M; Heijnen, J J; van Gulik, W M

    2015-08-01

    With the current quantitative metabolomics techniques, only whole-cell concentrations of NAD and NADH can be quantified. These measurements cannot provide information on the in vivo redox state of the cells, which is determined by the ratio of the free forms only. In this work we quantified free NAD:NADH ratios in yeast under anaerobic conditions, using alcohol dehydrogenase (ADH) and the lumped reaction of glyceraldehyde-3-phosphate dehydrogenase and 3-phosphoglycerate kinase as sensor reactions. We showed that, with an alternative accurate acetaldehyde determination method, based on rapid sampling, instantaneous derivatization with 2,4 diaminophenol hydrazine (DNPH) and quantification with HPLC, the ADH-catalysed oxidation of ethanol to acetaldehyde can be applied as a relatively fast and simple sensor reaction to quantify the free NAD:NADH ratio under anaerobic conditions. We evaluated the applicability of ADH as a sensor reaction in the yeast Saccharomyces cerevisiae, grown in anaerobic glucose-limited chemostats under steady-state and dynamic conditions. The results found in this study showed that the cytosolic redox status (NAD:NADH ratio) of yeast is at least one order of magnitude lower, and is thus much more reduced, under anaerobic conditions compared to aerobic glucose-limited steady-state conditions. The more reduced state of the cytosol under anaerobic conditions has major implications for (central) metabolism. Accurate determination of the free NAD:NADH ratio is therefore of importance for the unravelling of in vivo enzyme kinetics and to judge accurately the thermodynamic reversibility of each redox reaction. Copyright © 2015 John Wiley & Sons, Ltd.

  16. EXAMINATION OF THE SIMULATED THERMAL CONDITIONS IN A POPULAR PLAYGROUND RELATED TO THE HUMAN REACTIONS AND THE JUDGMENT OF THE AREA DESIGN

    OpenAIRE

    L.A. ÉGERHÁZI; A. KOVÁCS; N. KÁNTOR; J. UNGER

    2013-01-01

    In the field of urban bioclimatology an important and timely research direction today is to examine the thermal conditions of public places. In our study, human thermal comfort analysis was performed in a modern and well-attended children playground located in Szeged (Hungary). The aim of the paper is to reveal the changes in the thermal comfort conditions between two seasons and also the resulting subjective thermal reactions of visitors in this relatively small area. Thermal comfort conditi...

  17. Optimized Reaction Conditions for Removal of Cellular Organic Matter of Microcystis aeruginosa During the Destabilization and Aggregation Process Using Ferric Sulfate in Water Purification

    Czech Academy of Sciences Publication Activity Database

    Pivokonský, Martin; Polášek, Pavel; Pivokonská, Lenka; Tomášková, Hana

    2009-01-01

    Roč. 81, č. 5 (2009), s. 514-522 ISSN 1061-4303 R&D Projects: GA ČR GA103/07/0295 Institutional research plan: CEZ:AV0Z20600510 Keywords : Microcystis aeruginosa * cellular organic matter * destabilization * aggregation * optimized reaction conditions * water purification Subject RIV: BK - Fluid Dynamics Impact factor: 0.965, year: 2009

  18. CATALYST-FREE REACTIONS UNDER SOLVENT-FEE CONDITIONS: MICROWAVE-ASSISTED SYNTHESIS OF HETEROCYCLIC HYDRAZONES BELOW THE MELTING POINT OF NEAT REACTANTS: JOURNAL ARTICLE

    Science.gov (United States)

    NRMRL-CIN-1437 Jeselnik, M., Varma*, R.S., Polanc, S., and Kocevar, M. Catalyst-free Reactions under Solvent-fee Conditions: Microwave-assisted Synthesis of Heterocyclic Hydrazones below the Melting Point of Neat Reactants. Published in: Chemical Communications 18:1716-1717 (200...

  19. Synthesis of 1-amidoalkyl-2-naphthols based on a three-component reaction catalyzed by boric acid as a solid heterogeneous catalyst under solvent-free conditions

    Directory of Open Access Journals (Sweden)

    Zahed Karimi-Jaberi

    2012-12-01

    Full Text Available An efficient method for the preparation of 1-amidoalkyl-2-naphthols has been described using a multi-component, one-pot condensation reaction of 2-naphthol, aldehydes and amides in the presence of boric acid under solvent-free conditions.DOI: http://dx.doi.org/10.4314/bcse.v26i3.18

  20. CO oxidation on PtSn nanoparticle catalysts occurs at the interface of Pt and Sn oxide domains formed under reaction conditions

    KAUST Repository

    Michalak, William D.

    2014-04-01

    The barrier to CO oxidation on Pt catalysts is the strongly bound adsorbed CO, which inhibits O2 adsorption and hinders CO2 formation. Using reaction studies and in situ X-ray spectroscopy with colloidally prepared, monodisperse ∼2 nm Pt and PtSn nanoparticle catalysts, we show that the addition of Sn to Pt provides distinctly different reaction sites and a more efficient reaction mechanism for CO oxidation compared to pure Pt catalysts. To probe the influence of Sn, we intentionally poisoned the Pt component of the nanoparticle catalysts using a CO-rich atmosphere. With a reaction environment comprised of 100 Torr CO and 40 Torr O2 and a temperature range between 200 and 300 C, Pt and PtSn catalysts exhibited activation barriers for CO2 formation of 133 kJ/mol and 35 kJ/mol, respectively. While pure Sn is readily oxidized and is not active for CO oxidation, the addition of Sn to Pt provides an active site for O2 adsorption that is important when Pt is covered with CO. Sn oxide was identified as the active Sn species under reaction conditions by in situ ambient pressure X-ray photoelectron spectroscopy measurements. While chemical signatures of Pt and Sn indicated intermixed metallic components under reducing conditions, Pt and Sn were found to reversibly separate into isolated domains of Pt and oxidic Sn on the nanoparticle surface under reaction conditions of 100 mTorr CO and 40 mTorr O2 between temperatures of 200-275 C. Under these conditions, PtSn catalysts exhibited apparent reaction orders in O2 for CO 2 production that were 0.5 and lower with increasing partial pressures. These reaction orders contrast the first-order dependence in O 2 known for pure Pt. The differences in activation barriers, non-first-order dependence in O2, and the presence of a partially oxidized Sn indicate that the enhanced activity is due to a reaction mechanism that occurs at a Pt/Sn oxide interface present at the nanoparticle surface. © 2014 Published by Elsevier Inc.

  1. Temperature dependence of carbon kinetic isotope effect for the oxidation reaction of ethane by OH radicals under atmospherically relevant conditions

    Science.gov (United States)

    Piansawan, Tammarat; Saccon, Marina; Laumer, Werner; Gensch, Iulia; Kiendler-Scharr, Astrid

    2015-04-01

    Modeling of the global distribution of atmospheric ethane sources and sinks by using the 13C isotopic composition requires accurate knowledge of the carbon kinetic isotope effect (KIE) of its atmospheric removal reactions. The quantum mechanical prediction implies the necessity to elucidate the temperature dependence of KIE within atmospherically relevant temperature range by experiment. In this study, the KIE and its temperature dependence for ethane oxidation by OH radicals was investigated at ambient pressure in a temperature range of 243 K to 303 K. The chemical reactions were carried out in a 15 L PFE reaction chamber, suspended in a thermally controlled oven. The isotope ratios of the gas phase components during the course of the reactions were measured by Thermal Desorption -- Gas Chromatography -- Isotope Ratio Mass Spectrometry (TD-GC-IRMS). For each temperature, the KIE was derived from the temporal evolution of the concentration and stable carbon isotope ratio (δ13C) of ethane using a method adapted from the relative reaction rate concept. The room temperature KIE of the ethane reaction with OH radicals was found to be 6.85 ± 0.32 ‰. This value is in agreement with the previously reported value of 8.57 ± 1.95 ‰ [Anderson et al. 2004] but has a substantially lower uncertainty. The experimental results will be discussed with the KIE temperature dependence predicted by quantum mechanical calculations. Reference: Rebecca S. Anderson, Lin Huang, Richard Iannone, Alexandra E. Thompson, and Jochen Rudolph (2004), Carbon Kinetic Isotope Effects in the Gas Phase Reactions of Light Alkanes and Ethene with the OH Radical at 296 ± 4 K, J. Phys. Chem. A, 108, 11537--11544

  2. Polyionic polymers – heterogeneous media for metal nanoparticles as catalyst in Suzuki–Miyaura and Heck–Mizoroki reactions under flow conditions

    Directory of Open Access Journals (Sweden)

    Klaas Mennecke

    2009-05-01

    Full Text Available The preparation of monolithic polyionic supports which serve as efficient heterogeneous supports for palladium(0 nanoparticles is described. These functionalized polymers were incorporated inside a flow reactor and employed in Suzuki–Miyaura and Heck cross couplings under continuous flow conditions.

  3. The Homocoupling Reaction of Aromatic Terminal Alkynes by a Highly Active Palladium(II)/AgNO₃ Cocatalyst in Aqueous Media Under Aerobic Conditions.

    Science.gov (United States)

    Guo, Mengping; Chen, Bo; Lv, Meiyun; Zhou, Xiuling; Wen, Yongju; Shen, Xiuli

    2016-05-10

    A new and efficient Pd(II)/AgNO₃-cocatalyzed homocoupling of aromatic terminal alkynes is described. Various symmetrical 1,4-disubstituted-1,3-diynes are obtained in good to excellent yields. This protocol employs a loading with relatively low palladium(II) in aqueous media under aerobic conditions.

  4. Stress reaction in crayfish: chlorides help to withstand stress in high nitrite concentration conditions – preliminary study

    Directory of Open Access Journals (Sweden)

    Kozák P.

    2011-06-01

    Full Text Available A non-invasive method of recording cardiac activity (heart rate – HR and stress reaction (stress index – SI was used to understand the immediate and ongoing stress reaction of crayfish to the chemical stimuli. This method detects changes in the shape and amplitude parameters of the response to the stress factors, which characterized the crayfish functional state. Experimental animals (Astacus leptodactylus were divided to the two groups with (400 mg·L-1 Cl− and without added chlorides and then exposed to a stepwise increased level of nitrite to the final (sublethal-lethal concentration of 60 mg·L-1 N-NO\\hbox{$_{2}^{-}$}−2 within 24 hours. The course of crayfish reaction was evident and provided information about their reaction to the sublethal-lethal concentration over time. As expected, a less prominent stress reaction was detected in the group with chlorides. The non-invasive method successfully evaluated the sensing of chemical stimuli in water through HR and SI changes.

  5. Materials and Mechanisms of Photo-Assisted Chemical Reactions under Light and Dark Conditions: Can Day-Night Photocatalysis Be Achieved?

    Science.gov (United States)

    Sakar, M; Nguyen, Chinh-Chien; Vu, Manh-Hiep; Do, Trong-On

    2018-03-09

    The photoassisted catalytic reaction, conventionally known as photocatalysis, is expanding into the field of energy and environmental applications. It is widely known that the discovery of TiO 2 -assisted photochemical reactions has led to several unique applications, such as degradation of pollutants in water and air, hydrogen production through water splitting, fuel conversion, cancer treatment, antibacterial activity, self-cleaning glasses, and concrete. These multifaceted applications of this phenomenon can be enriched and expanded further if this process is equipped with more tools and functions. The term "photoassisted" catalytic reactions clearly emphasizes that photons are required to activate the catalyst; this can be transcended even into the dark if electrons are stored in the material for the later use to continue the catalytic reactions in the absence of light. This can be achieved by equipping the photocatalyst with an electron-storage material to overcome current limitations in photoassisted catalytic reactions. In this context, this article sheds lights on the materials and mechanisms of photocatalytic reactions under light and dark conditions. The manifestation of such systems could be an unparalleled technology in the near future that could influence all spheres of the catalytic sciences. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. A new rapid method for quantification of nitrogen in human serum employing the 14N(p,p' γ)14N reaction: application to human pregnancy

    International Nuclear Information System (INIS)

    Nikkenien, P.; Hyvoenen-Dabek, M.; Raeisaenen, J.; Haenninen, R.; Dabek, J.T.

    1985-01-01

    The total nitrogen concentrations in dried serum from 54 pregnant women and 17 newborn babies were determined by a new application of the 14 N(p,p'γ) 14 N reaction resonance at 3.9 MeV. The samples were bombarded in a He atmosphere by 4.1 MeV protons from a tandem Van de Graaff accelerator. The mean dry-weight nitrogen concentration in serum sampled during early pregnancy (6-12 weeks; 13.9 g per 100 g+-5.4%) was significantly higher than that in serum sampled during late pregnancy (38-42 weeks: 13.0 g per 100 g+-3.9%, p<0.001) than that in serum taken from the umbilical cord (13.3 g per 100 g+-4.6%, p<0.01). The nitrogen levels measured using this rapid nuclear technique, applied for the first time to human serum analysis, agree well with parallel Kjeldahl analyses. (author)

  7. Unsteady MHD Mixed Convection Slip Flow of Casson Fluid over Nonlinearly Stretching Sheet Embedded in a Porous Medium with Chemical Reaction, Thermal Radiation, Heat Generation/Absorption and Convective Boundary Conditions.

    Science.gov (United States)

    Ullah, Imran; Bhattacharyya, Krishnendu; Shafie, Sharidan; Khan, Ilyas

    2016-01-01

    Numerical results are presented for the effect of first order chemical reaction and thermal radiation on mixed convection flow of Casson fluid in the presence of magnetic field. The flow is generated due to unsteady nonlinearly stretching sheet placed inside a porous medium. Convective conditions on wall temperature and wall concentration are also employed in the investigation. The governing partial differential equations are converted to ordinary differential equations using suitable transformations and then solved numerically via Keller-box method. It is noticed that fluid velocity rises with increase in radiation parameter in the case of assisting flow and is opposite in the case of opposing fluid while radiation parameter has no effect on fluid velocity in the forced convection. It is also seen that fluid velocity and concentration enhances in the case of generative chemical reaction whereas both profiles reduces in the case of destructive chemical reaction. Further, increase in local unsteadiness parameter reduces fluid velocity, temperature and concentration. Over all the effects of physical parameters on fluid velocity, temperature and concentration distribution as well as on the wall shear stress, heat and mass transfer rates are discussed in detail.

  8. A reaction cell with sample laser heating for in situ soft X-ray absorption spectroscopy studies under environmental conditions.

    Science.gov (United States)

    Escudero, Carlos; Jiang, Peng; Pach, Elzbieta; Borondics, Ferenc; West, Mark W; Tuxen, Anders; Chintapalli, Mahati; Carenco, Sophie; Guo, Jinghua; Salmeron, Miquel

    2013-05-01

    A miniature (1 ml volume) reaction cell with transparent X-ray windows and laser heating of the sample has been designed to conduct X-ray absorption spectroscopy studies of materials in the presence of gases at atmospheric pressures. Heating by laser solves the problems associated with the presence of reactive gases interacting with hot filaments used in resistive heating methods. It also facilitates collection of a small total electron yield signal by eliminating interference with heating current leakage and ground loops. The excellent operation of the cell is demonstrated with examples of CO and H2 Fischer-Tropsch reactions on Co nanoparticles.

  9. Natural analogue studies of bentonite reaction under hyperalkaline conditions. Overview of ongoing work at the Zambales ophiolite, Philippines

    International Nuclear Information System (INIS)

    Fujii, N.; Yanakawa, M.; Arcilla, C.A.; Pascua, C.; Namiki, K.; Sato, T.; Shikazono, N.; Alexander, W.R.

    2011-01-01

    Bentonite is one of the safety-critical components of the engineered barrier system for the disposal concepts developed for many types of radioactive waste. However, bentonite - especially the swelling clay component that contributes to its essential barrier functions - is unstable at high pH. To date, results from laboratory tests on bentonite degradation have been ambiguous as the reaction rates are so slow as to be difficult to observe. As such, a key goal in this project is to examine the reaction of natural bentonites in contact with natural hyperalkaline groundwaters to determine if any long-term alteration of the bentonite occurs. Ophiolites have been identified as sources of hyperalkaline groundwaters that can be considered natural analogues of the leachates produced by some cementitious materials in repositories for radioactive waste. At the Zambales ophiolite in the Philippines, widespread active serpentinisation results in hyperalkaline groundwaters with measured pH values of up to 11.7, falling into the range typical of low-alkali cement porewaters. These cements are presently being developed worldwide to minimise the geochemical perturbations which are expected to result from the use of OPC-based concretes (see Kamei et al., this conference, for details). In particular, it is hoped that the lower pH of the low-alkali cement leachates will reduce, or even avoid entirely, the potential degradation of the bentonite buffer which is expected at the higher pH levels (12.5 and above) common to OPC-based concretes. During recent field campaigns at two sites in the Zambales ophiolite (Mangatarem and Bigbiga), samples of bentonite and the associated hyperalkaline groundwaters have been collected by drilling and trenching. At Mangatarem, qualitative data from a 'fossil' (i.e. no groundwater is currently present) reaction zone indicates some alteration of the bentonite to zeolite, serpentine and CSH phases. Preliminary reaction path modelling suggests that the

  10. Employer Branding

    OpenAIRE

    Stroblová, Zuzana

    2017-01-01

    The aim of the Master Thesis is to describe how to build Employer Brand a company. It is based on the description of Employer Branding project of a particular company and the evaluation its process. The thesis is a case study and consists of theoretical and practical part. The theoretical part focuses on trends and changes in leadership approach, definition of Employer Branding and HR Marketing. The practical part deals with the brand building process itself, describes the outputs of the proj...

  11. Employer branding

    OpenAIRE

    Mičková, Kateřina

    2008-01-01

    The demand for qualified employees is higher then the offering, both in Czech republic and internationally. Demand for specific skills, in addition to a greater demand for workforce generally, is making employee recruitment and retention much more difficult and expensive. Employer Branding claims to be an answer to this new challenge. This international concept focuses on developing an "employer brand" - mental image of a company as an employer. To achieve this, it is necessary to demonstrate...

  12. How Pragmatic Interpretations Arise from Conditionals: Profiling the Affirmation of the Consequent Argument with Reaction Time and EEG Measures

    Science.gov (United States)

    Bonnefond, Mathilde; Van der Henst, Jean-Baptiste; Gougain, Marion; Robic, Suzanne; Olsen, Matthew D.; Weiss, Oshri; Noveck, Ira

    2012-01-01

    Conditional reasoning consists in combining a conditional premise with a categorical premise and inferring a conclusion from them. Two well-known conditional arguments are Modus Ponens (MP: "If P then Q; P//"therefore Q), which is logically valid and Affirmation of the Consequent (AC: "If P then Q; Q//"therefore "P"), which is not. The latter is…

  13. Reaction mechanisms and kinetics of processing glucose, xylose and glucose-xylose mixtures under hot compressed water conditions for predicting bio-crude composition

    DEFF Research Database (Denmark)

    Grigoras, Ionela; Toor, Saqib Sohail; Rosendahl, Lasse Aistrup

    Mechanisms for bio-crude formation during the conversion of glucose, xylose and glucose-xylose mixtures as biomass model compounds under hot compressed water conditions are investigated. Studies in literature have shown that the diverse products formed at the early stages of glucose or xylose...... conversion are 5-HMF, erythrose, glyceraldehyde, dihydroxyacetone, pyruvaldehyde, and saccharinic acids resulted through reactions such as dehydration, retro-aldol condensation and isomerization. However, these compounds are mostly water soluble compounds and lack the final steps towards formation of water...... insoluble components at longer reaction times. The effects of pressure, pH, catalyst and reaction time on the main products are examined thoroughly. The possible routes for the formation of oil compounds are developed....

  14. Microwave-assisted clean synthesis of amides via aza-wittig reaction under solvent-free condition

    Energy Technology Data Exchange (ETDEWEB)

    Sathishkumar, Murugan; Nagarajan, Sangaraiah; Velan, Poovan Shanmuga; Dinesh, Murugan; Ponnuswamy, Alagusundaram [Department of Organic Chemistry, School of Chemistry, Madurai Kamaraj University, Tamilnadu (India)

    2011-09-15

    A solvent-free microwave-assisted coupling of phosphazenes with acyl chlorides or carboxylic anhydrides in presence of triethylphosphite has been accomplished resulting in a clean synthesis of amides in good yields. Unlike the prevailing time-consuming solution phase methodologies employing chlorinated solvents, benzene (carcinogenic), etc, the present protocol is an eco friendly, rapid and simple approach. (author)

  15. Employer Toolkit.

    Science.gov (United States)

    Thuli, Kelli J.; Hong, Esther

    This document consists of two guides intended for either employers or service providers involved in school to work partnerships for students with disabilities. "Tools for Service Providers" is intended to be used for training local-level providers who are developing school to work linkages with employers. Following an introduction, this…

  16. Effects of Thermal Radiation and Chemical Reaction on MHD Free Convection Flow past a Flat Plate with Heat Source and Convective Surface Boundary Condition

    OpenAIRE

    E.Hemalatha; N. Bhaskar Reddy

    2015-01-01

    This paper analyzes the radiation and chemical reaction effects on MHD steady two-dimensional laminar viscous incompressible radiating boundary layer flow over a flat plate in the presence of internal heat generation and convective boundary condition. It is assumed that lower surface of the plate is in contact with a hot fluid while a stream of cold fluid flows steadily over the upper surface with a heat source that decays exponentially. The Rosseland approximation is used to desc...

  17. Conditions of Employment and Income Distribution in Mexico as Incentives for Mexican Migration to the United States: Prospects to the End of the Century.

    Science.gov (United States)

    James, Dilmus D.; Evans, John S.

    1979-01-01

    This paper examines factors contributing to the flow of undocumented migrants from Mexico, demonstrating the problem to be both massive and enduring. Focused on are the inadequate growth of productive employment, income inequality, and rapid population growth. (Author/EB)

  18. VIA Employability

    DEFF Research Database (Denmark)

    Andersen, Henrik Mariendal

    2017-01-01

    ’s realized at the entrance to the labor market and in the future career. The purpose is to find opportunities to improve employability-developing activities and to adapt it to specific needs from the students. Based on a number of qualitative interviews and personality tests of the graduates, an increased......The fact that students develop employability during their education is a key point for educational institutions and the focus on this issue has never been greater. This project looks into personal experience from VIA-graduates of "developing their employability" during the education and how it...

  19. Effects of operating conditions on compositional characteristics and reaction kinetics of liquid derived by delayed coking of nigerian petroleum residue

    Directory of Open Access Journals (Sweden)

    O. O. Bello

    2006-09-01

    Full Text Available The thermal upgrading of Nigerian petroleum residue was studied at relatively low pressure in a delayed coking reactor system. In this work, the intent was to investigate the effects of process variables such as reaction temperature (200(0C to 600(0C, reaction time (0 to 120min, additive concentration loading and additive-to-residue ratio on the amounts and quality of organic liquid product (OLP. The liquid products derived from the delayed coking process were characterized by means of instrumental analysis of gas-liquid chromatography. Results obtained from the analyses of the OLP revealed an upward trend of the conversion process and the selectivity of the aromatic compounds with additive-to-residue ratio (ARR and increase in temperature. This led to maximum yield of 37.2% achieved with ARR of 5 compared to 31% achieved with ordinary thermal conversion. The selectivity for aromatic hydrocarbons was maximum at 83.1wt% the selectivity towards aromatics and aliphatic hydrocarbons were highest for methanol-potassium hydroxide and methanol respectively. In all additive system cases, maximum OLP was produced at an optimum reaction temperature of 370(0C in the delayed coking reactor and at higher residence time. The gaseous product consisted of carbon monoxide and carbon dioxide and C1 - C6 hydrocarbons, which amounted to about 20 to 30 wt% of liquid distillate. The information obtained in this study show that the organic liquid products are amenable to characterization procedure and provided the basis for the identification of processes for upgrading Nigerian petroleum residue and such other starting materials such as bitumen or fossil fuel coal liquids.

  20. Employment protection

    OpenAIRE

    Stefano Scarpetta

    2014-01-01

    Laws on hiring and firing are intended to protect workers from unfair behavior by employers, to counter imperfections in financial markets that limit workers’ ability to insure themselves against job loss, and to preserve firm-specific human capital. But by imposing costs on firms’ adaptation to changes in demand and technology, employment protection legislation may reduce not only job destruction but also job creation, hindering the efficient allocation of labor and productivity growth....

  1. Dynamic of bioelectric activity back hypothalamus changes in conditions of pyroxan application on the background of stress-reaction developmen

    Directory of Open Access Journals (Sweden)

    T. G. Chaus

    2005-04-01

    Full Text Available The dynamic of changes of capacity of electroencephalogram’s rhythms back hypothalamus at animals of control group and group in stress conditions in parallel with rats who on a background of stress development accepted pyroxan is analyzed. The submitted results have shown influence of a pharmacological preparation pyroxan on bioelectric activity of back hypothalamus in stress conditions that restoration of electric activity under action of this preparation was more shown at 3 weeks of its application.

  2. Sable Offshore Energy Inc.: Response to 'The Canada-Nova Scotia Offshore Petroleum Board Benefits Plan Decision Report' Condition No. 3: Employment and Training Plan; Condition No. 4: Research and Development Plan; Condition No. 6: Disadvantaged Individual or Groups; Condition No. 7: Technology Transfer

    International Nuclear Information System (INIS)

    1998-01-01

    Decisions of the Canada-Nova Scotia Offshore Petroleum Board, regarding the responses of Sable Offshore Energy Inc (SOEI) to conditions imposed by the Board in the Sable Offshore Energy Project Canada-Nova Scotia Benefit Plan Decision Report, have been announced. According to the press release (copy attached), the Board accepted the responses of SOEI regarding the establishment and staffing of an office in Nova Scotia for the implementation and project management and training of project personnel, the level of expenditures for research and development to be undertaken in Nova Scotia, proposed initiatives for employment and training opportunities for disadvantaged individuals and groups, and a technology transfer plan that will facilitate succession planning and create joint venturing opportunities for Nova Scotian and Canadian industry. tabs., figs

  3. Encouraging conceptual change: the use of bridging analogies in the teaching of action reaction forces and the `at rest' condition in physics

    Science.gov (United States)

    Bryce, Tom; MacMillan, Kenneth

    2005-06-01

    The qualitative study described in this paper examined the effectiveness of bridging analogies intended to bring about conceptual change as part of a constructivist approach to teaching about action reaction forces in the ‘at rest’ condition in physics. Twenty-one 15-year-old students were involved in the investigation with subgroups previously exposed to different information regarding forces, weight and the accepted cause of the reaction force, in simple physical arrangements, including objects on tables. In-depth ‘think aloud’ interviews were used to track each student’s conceptual status as they worked with bridging analogies and transcript coding was carried out using open and axial coding (as in a grounded theory methodology). The findings showed that the bridging analogies were effective in engaging students with the idea of action reaction forces; students were adept in mapping each of the analogies to the target concept and using them to generate and refine their causal theories for the reaction force. There was evidence to suggest that, for some students, bridging analogies were more effective in bringing about conceptual change than didactic teaching. Their use extends beyond illustrative purposes and supports the development of meta-cognitive skills.

  4. Lie and Q-Conditional Symmetries of Reaction-Diffusion-Convection Equations with Exponential Nonlinearities and Their Application for Finding Exact Solutions

    Directory of Open Access Journals (Sweden)

    Roman Cherniha

    2018-04-01

    Full Text Available This review is devoted to search for Lie and Q-conditional (nonclassical symmetries and exact solutions of a class of reaction-diffusion-convection equations with exponential nonlinearities. A complete Lie symmetry classification of the class is derived via two different algorithms in order to show that the result depends essentially on the type of equivalence transformations used for the classification. Moreover, a complete description of Q-conditional symmetries for PDEs from the class in question is also presented. It is shown that all the well-known results for reaction-diffusion equations with exponential nonlinearities follow as particular cases from the results derived for this class of reaction-diffusion-convection equations. The symmetries obtained for constructing exact solutions of the relevant equations are successfully applied. The exact solutions are compared with those found by means of different techniques. Finally, an application of the exact solutions for solving boundary-value problems arising in population dynamics is presented.

  5. Mn"4"+-activated BaSiF_6 red phosphor: Hydrothermal synthesis and dependence of its luminescent properties on reaction conditions

    International Nuclear Information System (INIS)

    Zhou, Qiang; Zhou, Yayun; Lu, Fengqi; Liu, Yong; Wang, Qin; Luo, Lijun; Wang, Zhengliang

    2016-01-01

    In this work, a series of BaSiF_6:Mn"4"+ red phosphors were synthesized through a hydrothermal route. The crystal structure and morphology were characterized by powder X-ray diffraction (XRD) with Rietveld refinement, scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS) in detail. The influence of reaction conditions, including the concentration of KMnO_4 and HF, reaction temperature and time, on the photoluminescence properties were investigated systematically. It can emit intense red light (∼636 nm) under blue light (∼458 nm) illumination. The white LED device based on YAG:Ce–BaSiF_6:Mn"4"+ mixture shows warm white light with low color temperature and high correlated color index, which reveals its potential application in WLED. - Highlights: • The crystal structure of BaSiF_6:Mn"4"+ has been verified using Rietveld refinement. • The optimum hydrothermal reaction condition for BaSiF_6:Mn"4"+ has been confirmed. • The white LED based on YAG:Ce–BaSiF_6:Mn"4"+ mixture presents warmer white light than that only with YAG:Ce.

  6. Mn{sup 4+}-activated BaSiF{sub 6} red phosphor: Hydrothermal synthesis and dependence of its luminescent properties on reaction conditions

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Qiang; Zhou, Yayun [Key Laboratory of Comprehensive Utilization of Mineral Resources in Ethnic Regions, Joint Research Centre for International Cross-border Ethnic Regions Biomass Clean Utilization in Yunnan, School of Chemistry & Environment, Yunnan Minzu University, Kunming, 650500 (China); Lu, Fengqi [MOE Key Laboratory of New Processing Technology for Nonferrous Metals and Materials, College of Materials Science and Engineering, Guilin University of Technology, Guilin, 541004 (China); Liu, Yong [Key Laboratory of Comprehensive Utilization of Mineral Resources in Ethnic Regions, Joint Research Centre for International Cross-border Ethnic Regions Biomass Clean Utilization in Yunnan, School of Chemistry & Environment, Yunnan Minzu University, Kunming, 650500 (China); Wang, Qin [College of Chemistry and Chemical Engineering, Yunnan Normal University, Kunming, Yunnan, 650500 (China); Luo, Lijun [Key Laboratory of Comprehensive Utilization of Mineral Resources in Ethnic Regions, Joint Research Centre for International Cross-border Ethnic Regions Biomass Clean Utilization in Yunnan, School of Chemistry & Environment, Yunnan Minzu University, Kunming, 650500 (China); Wang, Zhengliang, E-mail: wangzhengliang@foxmail.com [Key Laboratory of Comprehensive Utilization of Mineral Resources in Ethnic Regions, Joint Research Centre for International Cross-border Ethnic Regions Biomass Clean Utilization in Yunnan, School of Chemistry & Environment, Yunnan Minzu University, Kunming, 650500 (China)

    2016-02-15

    In this work, a series of BaSiF{sub 6}:Mn{sup 4+} red phosphors were synthesized through a hydrothermal route. The crystal structure and morphology were characterized by powder X-ray diffraction (XRD) with Rietveld refinement, scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS) in detail. The influence of reaction conditions, including the concentration of KMnO{sub 4} and HF, reaction temperature and time, on the photoluminescence properties were investigated systematically. It can emit intense red light (∼636 nm) under blue light (∼458 nm) illumination. The white LED device based on YAG:Ce–BaSiF{sub 6}:Mn{sup 4+} mixture shows warm white light with low color temperature and high correlated color index, which reveals its potential application in WLED. - Highlights: • The crystal structure of BaSiF{sub 6}:Mn{sup 4+} has been verified using Rietveld refinement. • The optimum hydrothermal reaction condition for BaSiF{sub 6}:Mn{sup 4+} has been confirmed. • The white LED based on YAG:Ce–BaSiF{sub 6}:Mn{sup 4+} mixture presents warmer white light than that only with YAG:Ce.

  7. Efficient transfer hydrogenation reaction Catalyzed by a dearomatized PN 3P ruthenium pincer complex under base-free Conditions

    KAUST Repository

    He, Lipeng

    2012-03-01

    A dearomatized complex [RuH(PN 3P)(CO)] (PN 3PN, N′-bis(di-tert-butylphosphino)-2,6-diaminopyridine) (3) was prepared by reaction of the aromatic complex [RuH(Cl)(PN 3P)(CO)] (2) with t-BuOK in THF. Further treatment of 3 with formic acid led to the formation of a rearomatized complex (4). These new complexes were fully characterized and the molecular structure of complex 4 was further confirmed by X-ray crystallography. In complex 4, a distorted square-pyramidal geometry around the ruthenium center was observed, with the CO ligand trans to the pyridinic nitrogen atom and the hydride located in the apical position. The dearomatized complex 3 displays efficient catalytic activity for hydrogen transfer of ketones in isopropanol. © 2011 Elsevier B.V. All rights reserved.

  8. Optimal conditions to use Pfu exo(-) DNA polymerase for highly efficient ligation-mediated polymerase chain reaction protocols.

    Science.gov (United States)

    Angers, M; Cloutier, J F; Castonguay, A; Drouin, R

    2001-08-15

    Ligation-Mediated Polymerase Chain Reaction (LMPCR) is the most sensitive sequencing technique available to map single-stranded DNA breaks at the nucleotide level of resolution using genomic DNA. LMPCR has been adapted to map DNA damage and reveal DNA-protein interactions inside living cells. However, the sequence context (GC content), the global break frequency and the current combination of DNA polymerases used in LMPCR affect the quality of the results. In this study, we developed and optimized an LMPCR protocol adapted for Pyrococcus furiosus exo(-) DNA polymerase (Pfu exo(-)). The relative efficiency of Pfu exo(-) was compared to T7-modified DNA polymerase (Sequenase 2.0) at the primer extension step and to Thermus aquaticus DNA polymerase (Taq) at the PCR amplification step of LMPCR. At all break frequencies tested, Pfu exo(-) proved to be more efficient than Sequenase 2.0. During both primer extension and PCR amplification steps, the ratio of DNA molecules per unit of DNA polymerase was the main determinant of the efficiency of Pfu exo(-), while the efficiency of Taq was less affected by this ratio. Substitution of NaCl for KCl in the PCR reaction buffer of Taq strikingly improved the efficiency of the DNA polymerase. Pfu exo(-) was clearly more efficient than Taq to specifically amplify extremely GC-rich genomic DNA sequences. Our results show that a combination of Pfu exo(-) at the primer extension step and Taq at the PCR amplification step is ideal for in vivo DNA analysis and DNA damage mapping using LMPCR.

  9. Summary of United States Geological Survey investigations of fluid-rock-waste reactions in evaporite environments under repository conditions

    International Nuclear Information System (INIS)

    Stewart, D.B.; Jones, B.F.; Roedder, E.; Potter, R.W. II

    1980-01-01

    The interstitial and inclusion fluids contained in rock salt and anhydrite, though present in amounts less than 1 weight per cent, are chemically aggressive and may react with canisters or wastes. The three basic types of fluids are: (1) bitterns residual from saline mineral precipitation including later recrystallization reactions; (2) brines containing residual solutes from the formation of evaporite that have been extensively modified by reactions with contiguous carbonate of clastic rocks; and (3) re-solution brines resulting from secondary dehydration of evaporite minerals or solution of saline minerals by undersaturated infiltrating waters. Fluid composition can indicate that meteoric flow systems have contacted evaporites or that fluids from evaporites have migrated into other formations. The movement of fluids trapped in fluid inclusions in salt from southeast New Mexico is most sensitive to ambient temperature and to inclusion size, although several other factors such as thermal gradient and vapour/liquid ratio are also important. There is no evidence of a threshold temperature for movement of inclusions. Empirical data are given for determining the amount of brine reaching the heat source if the temperature, approximate amount of total dissolved solids, and Ca:Mg ratio in the brine are known. SrCl 2 and CsCl can reach high concentrations in saturated NaCl solutions and greatly depress the liquidus. The possibility that such fluids, if generated, could migrate from a high-level waste repository must be minimized because the fluid would contain its own radiogenic energy source in the first decades after repository closure, thus changing the thermal evolution of the repository from designed values. (author)

  10. Employer Branding

    DEFF Research Database (Denmark)

    Frimann, Søren; Mønsted, Bolette Rye

    2012-01-01

    Employer branding er både for den private og den offentlige sektor blevet en måde, de kan imødekomme ændrede arbejdsmarkedsvilkår og organisatoriske udfordringer i en postmoderne og globaliseret verden. Den aktuelle finanskrise har skabt nye udfordringer for organisationer i deres bestræbelser på...... at tiltrække- og fastholde attraktive medarbejdere. Men hvilken betydning har det, når Grundfos siger ”Mennesket er i fokus”, og hvad siger ”mangfoldighed” om Københavns Kommune som arbejdsplads i relation til employer branding? Er der egentlig sammenhæng mellem tankerne bag employer branding og de eksternt...... kommunikerede employer brandprodukter. Eller bliver det unikke ved arbejdspladserne ersattet af buzzwords uden substans og inddragelse af ansatte og interessenter? Artiklen har til formål at vurdere disse spørgsmål på baggrund af analyser af to cases med employer branding....

  11. Photocatalysis of the homogeneous water-gas shift reaction under ambient conditions by cationic iridium (III) complexes

    Energy Technology Data Exchange (ETDEWEB)

    Ziessel, R [Ecole Europeenne des Hautes Etudes des Industries Chimiques, 67 - Strasbourg (France)

    1991-07-01

    We describe here our results and mechanistic analysis of the first highly efficient light-assisted WGSR, which takes place under extremely mild conditions (room temperature, ambient pressure, neutral pH, visible light) and is catalyzed by novel Ir{sup III} pentamethylcyclopentadienyl complexes containing novel 4,4'-substituted bipyridine ligands. (orig./EF).

  12. Heat treatment of wet wood fiber: A study of the effect of reaction conditions on the formation of furfurals

    Science.gov (United States)

    Mandla A. Tshabalala; James D. McSweeny; Roger M. Rowell

    2012-01-01

    Furan monomers are produced when wood is heated at high temperatures. To understand the process conditions for production of furfural (FF) and hydroxymethylfurfural (HMF) from wood, samples of milled aspen wood were subjected to autohydrolyzis by microwave heating in a sealed Teflon reactor. The experiments were designed to simulate temperature and pressure variables...

  13. Student employment

    DEFF Research Database (Denmark)

    Jacob, Marita; Gerth, Maria; Weiss, Felix

    2018-01-01

    , according to social origins, in student employment from first-year students through graduating students. We show that inequality in job quality exists and is partly attributable to the need for students from lower social origins to work to finance their studies. We hypothesise that initial inequalities......In this article, we examine social origin differences in employment patterns across different stages of higher education and compare these differences between vocational and academic fields of study. Using data from a large-scale German student survey, we study the development of inequality...

  14. Co-solvents transesterification of cotton seed oil into biodiesel: Effects of reaction conditions on quality of fatty acids methyl esters

    International Nuclear Information System (INIS)

    Alhassan, Y.; Kumar, N.; Bugaje, I.M.; Pali, H.S.; Kathkar, P.

    2014-01-01

    Highlights: • Using co-solvent systems reduce reaction time by 60%. • Only small volume of co-solvent is required to improve the process. • Greater than 90% yields were obtained within the first 10 min. • Physico-chemical and fuel properties of FAMEs were within standard limits. • Acetone was found to be the best co-solvent for the transesterification. - Abstract: Solvent Technology, is gaining the interest of researchers in improving transesterification process recently. Transesterification of cotton seed oil into biodiesel using different mixtures of methanol with Diethyl Ether (DEE), Dichlorobenzene (CBN) or Acetone (ACT) co-solvent systems was conducted. Potassium hydroxide (KOH) was used as the catalyst all through. The reaction conditions optimized include; the molar ratio of co-solvent in methanol, reaction temperature and time. The catalyst concentration was also optimized. The optimization was based on the percentage yields of Fatty Acids Methyl Esters (FAMEs) produced. In addition, the effects of co-solvent systems on physico-chemical properties (Acid value and fatty acids composition) and fuel properties (viscosity, density and calorific value) were investigated as well. The result obtained, indicated 10% (v/v) addition of co-solvents CBN and ACT in methanol was the optimal volume. The optimal reaction temperature was 55 ° 0 C for 10 min when the catalyst concentration of 0.75% (w/w) weight of oil was used. Fuel properties were within the acceptable limit of ASTM and not significantly affected by the co-solvent systems except for the calorific value. It was concluded that the addition of co-solvent reduced the reaction time and improved some fuel properties of the biodiesel produced

  15. Impact of Flight Enthalpy, Fuel Simulant, and Chemical Reactions on the Mixing Characteristics of Several Injectors at Hypervelocity Flow Conditions

    Science.gov (United States)

    Drozda, Tomasz G.; Baurle, Robert A.; Drummond, J. Philip

    2016-01-01

    The high total temperatures or total enthalpies required to duplicate the high-speed flight conditions in ground experiments often place stringent requirements on the material selection and cooling needs for the test articles and intrusive flow diagnostic equipment. Furthermore, for internal flows, these conditions often complicate the use of nonintrusive diagnostics that need optical access to the test section and interior portions of the flowpath. Because of the technical challenges and increased costs associated with experimentation at high values of total enthalpy, an attempt is often made to reduce it. This is the case for the Enhanced Injection and Mixing Project (EIMP) currently underway in the Arc-Heated Scramjet Test Facility at the NASA Langley Research Center. The EIMP aims to investigate supersonic combustion ramjet (scramjet) fuel injection and mixing physics, improve the understanding of underlying physical processes, and develop enhancement strategies and functional relationships between mixing performance and losses relevant to flight Mach numbers greater than 8. The experiments will consider a "direct-connect" approach and utilize a Mach 6 nozzle to simulate the combustor entrance flow of a scramjet engine. However, while the value of the Mach number is matched to that expected at the combustor entrance in flight, the maximum value of the total enthalpy for these experiments is limited by the thermal-structural limits of the uncooled experimental hardware. Furthermore, the fuel simulant is helium, not hydrogen. The use of "cold" flows and non-reacting mixtures of fuel simulants for mixing experiments is not new and has been extensively utilized as a screening technique for scramjet fuel injectors. In this study, Reynolds-averaged simulations are utilized (RAS) to systematically verify the implicit assumptions used by the EIMP. This is accomplished by first performing RAS of mixing for two injector configurations at planned nominal experimental

  16. CONDITION ASSESSMENT OF SUBJECTIVE COMFORT AND THE REACTIONS OF THE POPULATION IN THE URBAN CONTEXT OF EXPOSURE TO NOISE

    Directory of Open Access Journals (Sweden)

    NICA-BADEA Delia

    2012-05-01

    Full Text Available The paper considers this issue matters as of interference noise of the ordinary activity of the population owing to its cause and its presence in all departments of life. Noise pollution is a major problem in all countries where we are witnessing a phenomenon of magnification levels of noise having effects more or less aggressive about comfort and even health. Are presented arguments relating to the characterization of noise as a risk factor in the induction of pathologies such as: auditory disorders, hypertension, ischemic heart disease aggravation, discomfort, sleep disorders and decreasing school performance in children. For the evaluation and management of ambient noise has developed a study aimed at assessing the state of comfort and subjective reactions of residents in order to fundamentarii measures for reducing the levels of exposure and prevention of the effects of population exposed to noise in the street. In areas with heavy traffic confirm the existence of risk perception of 56% of the people who accuse the discomfort caused by noise in homes during the day and during the night rate is 40%. The age groups most affected are 51-65 years and over 65 years old, because they spend most of the time period in the home.

  17. A new generation of the optimization techniques offers higher profits, visibility and faster reaction to market conditions

    International Nuclear Information System (INIS)

    Woolstencroft, W.

    2004-01-01

    The pace of change in the energy utility world is accelerating. The new political, environmental, and competitive pressures in all European countries mandate new ways to operate and find efficiencies. We are proposing a lot broader use of optimization technologies as they are starting to be practiced by lead edge energy companies. We will present a holistic case for optimization techniques at the global and local level that are integrated with distributed control systems and each other. They yield a very high degree of transparency, high speed optimization and fast reaction capability with complete profit understanding. This case deals with most of the pressures facing modern utility companies. It is most appropriate for companies that operate a wider variety of generating technologies and which support the central processes like asset management, portfolio optimization, and utilities production planning. We will present best practice examples from industry and give indications of the gains made by those already practicing these techniques. Gains of 3 to 5 % of variable operating costs are standard for fairly small IT and organizational behaviour adjustments. (author)

  18. EXAMINATION OF THE SIMULATED THERMAL CONDITIONS IN A POPULAR PLAYGROUND RELATED TO THE HUMAN REACTIONS AND THE JUDGMENT OF THE AREA DESIGN

    Directory of Open Access Journals (Sweden)

    L.A. ÉGERHÁZI

    2013-03-01

    Full Text Available In the field of urban bioclimatology an important and timely research direction today is to examine the thermal conditions of public places. In our study, human thermal comfort analysis was performed in a modern and well-attended children playground located in Szeged (Hungary. The aim of the paper is to reveal the changes in the thermal comfort conditions between two seasons and also the resulting subjective thermal reactions of visitors in this relatively small area. Thermal comfort conditions were quantified by the Physiologically Equivalent Temperature (PET. For typical summer and autumn days of 2011 numerical simulations of thermal comfort conditions in the playground were carried out by means of the urban microclimate model ENVI-met. Spatial distribution of the simulated PET, i.e. thermal stress maps were created in two different times of the selected days in order to characterize the distinct microclimatological conditions appearing in the area. The relationship between the momentary spatial patterns of visitors and the thermal conditions was also under investigation. Additionally, onsite questionnaire survey was implemented which highlights the people’s subjective evaluation related to the design of the playground.

  19. [The role of the working conditions in shaping the specific and nonspecific body reactions of miners in vibration-hazardous jobs].

    Science.gov (United States)

    Lastkov, D O

    1998-08-01

    An analysis was carried out of bodily functional status in miners engaged in basic mining occupations with known vibration-related health hazards (coal hewers, drifters), presenting with different stages of vibration pathology. Patterns were ascertained of chief components of both specific and unspecific bodily systemic reactions to a combined action of physical industrial factors (vibration, noise, dust, heating, microclimate). Important for those subjects engaged in occupations with vibration-related health threats are parameters characterizing labour conditions, such as, in the first place, integral-and-service duration-related exposure doses of industrial factors which are believed to be probabilistic risk factors for vibration pathology.

  20. The ReactorSTM: Atomically resolved scanning tunneling microscopy under high-pressure, high-temperature catalytic reaction conditions

    Energy Technology Data Exchange (ETDEWEB)

    Herbschleb, C. T.; Tuijn, P. C. van der; Roobol, S. B.; Navarro, V.; Bakker, J. W.; Liu, Q.; Stoltz, D.; Cañas-Ventura, M. E.; Verdoes, G.; Spronsen, M. A. van; Bergman, M.; Crama, L.; Taminiau, I.; Frenken, J. W. M., E-mail: frenken@physics.leidenuniv.nl [Huygens-Kamerlingh Onnes Laboratory, Leiden University, P.O. box 9504, 2300 RA Leiden (Netherlands); Ofitserov, A.; Baarle, G. J. C. van [Leiden Probe Microscopy B.V., J.H. Oortweg 21, 2333 CH Leiden (Netherlands)

    2014-08-15

    To enable atomic-scale observations of model catalysts under conditions approaching those used by the chemical industry, we have developed a second generation, high-pressure, high-temperature scanning tunneling microscope (STM): the ReactorSTM. It consists of a compact STM scanner, of which the tip extends into a 0.5 ml reactor flow-cell, that is housed in a ultra-high vacuum (UHV) system. The STM can be operated from UHV to 6 bars and from room temperature up to 600 K. A gas mixing and analysis system optimized for fast response times allows us to directly correlate the surface structure observed by STM with reactivity measurements from a mass spectrometer. The in situ STM experiments can be combined with ex situ UHV sample preparation and analysis techniques, including ion bombardment, thin film deposition, low-energy electron diffraction and x-ray photoelectron spectroscopy. The performance of the instrument is demonstrated by atomically resolved images of Au(111) and atom-row resolution on Pt(110), both under high-pressure and high-temperature conditions.

  1. Analysis of activation energy in Couette-Poiseuille flow of nanofluid in the presence of chemical reaction and convective boundary conditions

    Science.gov (United States)

    Zeeshan, A.; Shehzad, N.; Ellahi, R.

    2018-03-01

    The motivation of the current article is to explore the energy activation in MHD radiative Couette-Poiseuille flow nanofluid in horizontal channel with convective boundary conditions. The mathematical model of Buongiorno [1] effectively describes the current flow analysis. Additionally, the impact of chemical reaction is also taken in account. The governing flow equations are simplified with the help of boundary layer approximations. Non-linear coupled equations for momentum, energy and mass transfer are tackled with analytical (HAM) technique. The influence of dimensionless convergence parameter like Brownian motion parameter, radiation parameter, buoyancy ratio parameter, dimensionless activation energy, thermophoresis parameter, temperature difference parameter, dimensionless reaction rate, Schmidt number, Brinkman number, Biot number and convection diffusion parameter on velocity, temperature and concentration profiles are discussed graphically and in tabular form. From the results, it is elaborate that the nanoparticle concentration is directly proportional to the chemical reaction with activation energy and the performance of Brownian motion on nanoparticle concentration gives reverse pattern to that of thermophoresis parameter.

  2. Northern employment

    International Nuclear Information System (INIS)

    Zavitz, J.

    1997-01-01

    Hiring practices and policies and employment opportunities that were available in the Beaufort Sea and MacKenzie Delta project for local residents and for people from southern Canada were dealt with in this chapter. Depending on the source, Northern hiring was a mere token, or a genuine and successful effort on the part of the companies to involve the native population and to share with them the benefits of the project. The fact remains that opening up job opportunities for Northerners was not easily attained, and would never have been realized without the involvement of government and community organizations. Government also played a major role in developing policies and training regimes. By the end of exploration operations, the hiring of Northern residents in the oil and gas industry had become a requirement of drilling applications. Training programs were also created to ensure that Northern residents received the means necessary to take advantage of Northern employment opportunities

  3. Experimental Investigation of Augmented Spark Ignition of a LO2/LCH4 Reaction Control Engine at Altitude Conditions

    Science.gov (United States)

    Kleinhenz, Julie; Sarmiento, Charles; Marshall, William

    2012-01-01

    The use of nontoxic propellants in future exploration vehicles would enable safer, more cost-effective mission scenarios. One promising green alternative to existing hypergols is liquid methane (LCH4) with liquid oxygen (LO2). A 100 lbf LO2/LCH4 engine was developed under the NASA Propulsion and Cryogenic Advanced Development project and tested at the NASA Glenn Research Center Altitude Combustion Stand in a low pressure environment. High ignition energy is a perceived drawback of this propellant combination; so this ignition margin test program examined ignition performance versus delivered spark energy. Sensitivity of ignition to spark timing and repetition rate was also explored. Three different exciter units were used with the engine s augmented (torch) igniter. Captured waveforms indicated spark behavior in hot fire conditions was inconsistent compared to the well-behaved dry sparks. This suggests that rising pressure and flow rate increase spark impedance and may at some point compromise an exciter s ability to complete each spark. The reduced spark energies of such quenched deliveries resulted in more erratic ignitions, decreasing ignition probability. The timing of the sparks relative to the pressure/flow conditions also impacted the probability of ignition. Sparks occurring early in the flow could trigger ignition with energies as low as 1 to 6 mJ, though multiple, similarly timed sparks of 55 to 75 mJ were required for reliable ignition. Delayed spark application and reduced spark repetition rate both correlated with late and occasional failed ignitions. An optimum time interval for spark application and ignition therefore coincides with propellant introduction to the igniter.

  4. Evaluation of a polymerase chain reaction assay for pathogen detection in septic patients under routine condition: an observational study.

    Directory of Open Access Journals (Sweden)

    Frank Bloos

    Full Text Available BACKGROUND: Treatment of septic shock relies on appropriate antimicrobial therapy. Current culture based methods deliver final results after days, which may delay potentially lifesaving adjustments in antimicrobial therapy. This study was undertaken to compare PCR with blood culture results under routine conditions regarding 1. impact on antimicrobial therapy, and 2. time to result, in patients with presumed sepsis. METHODOLOGY/PRINCIPAL FINDINGS: This was an observational study in a 50 beds ICU of a university hospital. In 245 patients with suspected sepsis, 311 concomitant blood cultures and blood for multiplex PCR (VYOO(® were obtained. 45 of 311 blood cultures (14.5% and 94 of 311 PCRs (30.1% were positive. However, blood culture or microbiological sampling from the presumed site of infection rarely confirmed PCR results and vice versa. Median time to positivity and interquartile range were 24.2 (18.0, 27.5 hours for the PCR and 68 (52.2, 88.5 hours for BC (p<0.01. PCR median time to result was dependent on technician availability (53.5 hours on Saturdays, 7.2 hours under optimal logistic conditions. PCR results showed good correlation with procalcitonin (p<0.001. In 34% of patients with positive PCRs antimicrobial therapy was considered inadequate according to assessment of clinical arbitrators including 5 patients with vancomycin-resistant enterococci (VRE, 3 cases with multiresistant staphylococci, and 4 patients with fungi. CONCLUSIONS: The results of this observational study support the hypothesis that PCR results are available faster, are more frequently positive, and may result in earlier adjustment of antimicrobial therapy. However, shorter time to result can only be fully exploited when the laboratory is adequately staffed for a 24 hour/7 day service, or when point of care/automated assay systems become available.

  5. New Insight into the Hydrogen Evolution Reaction under Buffered Near-Neutral pH Conditions: Enthalpy and Entropy of Activation

    KAUST Repository

    Shinagawa, Tatsuya

    2016-10-06

    Electrochemical conversion of thermodynamically stable chemicals of water and carbon dioxide is regarded as a core technology for achieving sustainability in our society. In both cases, the electrochemical hydrogen evolution reaction (HER) is a key reaction, particularly at near-neutral pH. This study addresses the kinetic aspects of the HER in buffered near-neutral pH conditions using a variety of electrode materials (W, Ni, Pt, Au, and Cu) over a wide temperature range (299–346 K). When the overall performance was summarized with respect to the binding energy of the reaction intermediate species, a classic volcano-shaped relationship was obtained. Interestingly, the temperature sensitivity analysis disclosed that smaller activation energies did not always lead to higher performance in 1.5 mol L–1 K-phosphate solution (pH 5.8). Detailed analysis of the temperature- and potential-dependent parameters revealed that smaller activation energies coincided with smaller values of the pre-exponential factor in the Arrhenius’ equation (associated with the entropy of activation). Due to the trade-off relationship of enthalpy–entropy compensation in the current system, the conventional approach of mixing elements of lower and higher binding energies to the intermediate species failed: even though Ni–Cu showed lower apparent activation energy, its activity toward the HER was between that of Ni and Cu due to the lowered entropy of activation. This study demonstrates the unrevealed fundamental aspects of the HER in buffered near-neutral condition, which contributes to the rational development of efficient energy and material conversion systems.

  6. A Laboratory Test Setup for in Situ Measurements of the Dielectric Properties of Catalyst Powder Samples under Reaction Conditions by Microwave Cavity Perturbation: Set up and Initial Tests

    Directory of Open Access Journals (Sweden)

    Markus Dietrich

    2014-09-01

    Full Text Available The catalytic behavior of zeolite catalysts for the ammonia-based selective catalytic reduction (SCR of nitrogen oxides (NOX depends strongly on the type of zeolite material. An essential precondition for SCR is a previous ammonia gas adsorption that occurs on acidic sites of the zeolite. In order to understand and develop SCR active materials, it is crucial to know the amount of sorbed ammonia under reaction conditions. To support classical temperature-programmed desorption (TPD experiments, a correlation of the dielectric properties with the catalytic properties and the ammonia sorption under reaction conditions appears promising. In this work, a laboratory test setup, which enables direct measurements of the dielectric properties of catalytic powder samples under a defined gas atmosphere and temperature by microwave cavity perturbation, has been developed. Based on previous investigations and computational simulations, a resonator cavity and a heating system were designed, installed and characterized. The resonator cavity is designed to operate in its TM010 mode at 1.2 GHz. The first measurement of the ammonia loading of an H-ZSM-5 zeolite confirmed the operating performance of the test setup at constant temperatures of up to 300 °C. It showed how both real and imaginary parts of the relative complex permittivity are strongly correlated with the mass of stored ammonia.

  7. A laboratory test setup for in situ measurements of the dielectric properties of catalyst powder samples under reaction conditions by microwave cavity perturbation: set up and initial tests.

    Science.gov (United States)

    Dietrich, Markus; Rauch, Dieter; Porch, Adrian; Moos, Ralf

    2014-09-10

    The catalytic behavior of zeolite catalysts for the ammonia-based selective catalytic reduction (SCR) of nitrogen oxides (NOX) depends strongly on the type of zeolite material. An essential precondition for SCR is a previous ammonia gas adsorption that occurs on acidic sites of the zeolite. In order to understand and develop SCR active materials, it is crucial to know the amount of sorbed ammonia under reaction conditions. To support classical temperature-programmed desorption (TPD) experiments, a correlation of the dielectric properties with the catalytic properties and the ammonia sorption under reaction conditions appears promising. In this work, a laboratory test setup, which enables direct measurements of the dielectric properties of catalytic powder samples under a defined gas atmosphere and temperature by microwave cavity perturbation, has been developed. Based on previous investigations and computational simulations, a resonator cavity and a heating system were designed, installed and characterized. The resonator cavity is designed to operate in its TM010 mode at 1.2 GHz. The first measurement of the ammonia loading of an H-ZSM-5 zeolite confirmed the operating performance of the test setup at constant temperatures of up to 300 °C. It showed how both real and imaginary parts of the relative complex permittivity are strongly correlated with the mass of stored ammonia.

  8. Verification of an optimized condition for low residual stress employed water-shower cooling during welding in austenitic stainless steel plates

    International Nuclear Information System (INIS)

    Yanagida, N.; Enomoto, K.; Anzai, H.

    2004-01-01

    To reduce tensile residual stress in a welded region, we have developed a new cooling method that uses a water-shower behind the welding torch. When this method is applied to the welding of austenitic stainless steel, the welding and cooling conditions mainly determine how much the residual stress can be reduced. To optimize these conditions, we first used a robust design method to determine the effects of the preheating temperature, the heat input quantity, and the water-shower area on the residual stress, and found that, to decrease the tensile residual stress, the preheating temperature should be high, the heat input low, and the water-shower area large. To confirm the effectiveness of these optimized conditions, the residual stresses under optimized or non-optimized conditions were measured experimentally. It was found that the residual stresses were tensile under the non-optimized conditions, but compressive under the optimized ones. These measurements agree well with the 3D-FEM analyses. It can therefore be concluded that the optimized conditions are valid and appropriate for reducing residual stress in an austenitic stainless-steel weld. (orig.)

  9. The relationship between working conditions and self-rated health among medical doctors: evidence from seven waves of the Medicine In Australia Balancing Employment and Life (Mabel) survey.

    Science.gov (United States)

    Milner, Allison; Witt, Katrina; Spittal, Matthew J; Bismark, Marie; Graham, Melissa; LaMontagne, Anthony D

    2017-08-29

    Psychosocial job stressors, such as low control and high demands, have been found to influence the health and wellbeing of doctors. However, past research in this area has relied on cross-sectional data, which limits causal inferences about the influence of psychosocial job stressors on health. In this study, we examine this relationship longitudinally while also assessing whether the relationship between psychosocial job stressors and health is modified by gender. The data source was seven annual waves of the Medicine in Australia: Balancing Employment and Life (MABEL) survey. The outcome was self-rated health (measured using the SF-12), and key exposures reflected job control, job demands, work-life balance variables, employment arrangements, and aggression experienced at work. We used longitudinal fixed and random effects regression models to assess within and between-person changes in health. Excessive job demands, low job control, feelings of not being rewarded at work, and work-life imbalance were associated with higher within-person odds of poorer self-rated health. Gender differences were apparent. For female doctors, work arrangements and work-life imbalance were associated with poorer self-rated health whilst task-based job stressors were associated with poorer self-rated health in male doctors. These results suggest the importance of addressing adverse working environments among doctors. Not applicable.

  10. REACTION OF INTRODUCED BEAN (PHASEOLUS ACCESSIONS TO THE INFESTATION BY THIELAVIOPSIS BASICOLA (BERKELEY & BROOME UNDER NATURAL EPIPHYTOTIC CONDITIONS

    Directory of Open Access Journals (Sweden)

    O. Georgieva

    2015-01-01

    Full Text Available A periodic phytopathology field monitoring was conducted on 35 introduced common bean (Phaseolus accessions at Maritsa Vegetable Crops Research Institute in 2014. The epiphytotic disease black root rot on the bean crops (over 75 % reduction of the stand was recorded for the first time for the area of Bulgaria. The causal agent isolated from the plant tissue was identified as the fungus Thielaviopsis basicola (Berkeley Ferraris. A strong relationship between disease severity variation and environmental and soil conditions was established. Black root rot was most severe when cool and wet weather occurred from seedling time to about three weeks after planting, combined with increased soil compaction. Field resistance was recorded in Bulgarian var. “Plovdivski zult”, var. “Starozagorski tzer” and line № 564 (3,66%, 5.33% and 6,50 % dumping-off of bean seedlings, respectively. Bean accession introduced from dry climate areas were highly susceptible to black root rot pathogen (over 76.0 % dumping-off of bean seedlings. Indirect relationship was found between bean tolerance to Th. basicola and presence of the anthocyanin in the hypocotyl and seed coat color. Install the average negative correlation between seed color signs (and hypocotyl and the resistance of plants to Th. basicola. Samples with resistance to black root rot belong to the group with beige, red, brown or black color of seeds. The presence of phenolic compounds (anthocyanins in the seed coat and hypocotyls beans can serve as an indirect indication of the selection of resistant to black rot breeding materials.

  11. How are the employed and unemployed affected by the economic crisis in Spain? Educational inequalities, life conditions and mental health in a context of high unemployment.

    Science.gov (United States)

    Córdoba-Doña, Juan Antonio; Escolar-Pujolar, Antonio; San Sebastián, Miguel; Gustafsson, Per E

    2016-03-15

    Despite an increasing number of studies on the factors mediating the impact of the economic recession on mental health, research beyond the individual employment status is scarce. Our objectives were to investigate in which ways the mental health of employed and unemployed populations is differently affected by the current economic recession along the educational scale and to examine whether financial strain and social support explain these effects of the crisis. A repeated cross-sectional study, using two waves of the Andalusian Health Survey in 2007 (pre-crisis) and 2011-2012 (crisis). A population aged between 19 and 64 years was selected. The dependent variable was the Mental Component Summary of the SF-12 questionnaire. We performed Poisson regression models stratified by working status, with period, educational level, financial strain and social support as independent variables. We examined interactions between period and educational level. Age, sex, main earner, cohabitation and partner's working status were considered as covariates. The study included 3210 individuals (1185 women) in 2007 and 3633 individuals (1486 women) in 2011-2012. In working individuals the prevalence of poor mental health increased for secondary and complete primary studies groups during crisis compared to the pre-crisis period, while it decreased significantly in the university study group (PR = 0.76, 95% CI: 0.58-0.99). However, in unemployed individuals prevalence ratios for poor mental health increased significantly only in the secondary studies group (PR = 1.73, 95% CI: 1.06-2.83). Financial strain and social support yielded consistent associations with mental health in all subgroups. Only financial strain could partly explain the crisis effect on mental health among the unemployed. Our study supports the finding that current economic recession is associated with poorer mental health differentially according to labour market status and educational level. Those with secondary

  12. Simulation of the steady-state energy transfer in rigid bodies, with convective-radiative boundary conditions, employing a minimum principle

    International Nuclear Information System (INIS)

    Gama, R.M.S. da.

    1992-08-01

    The energy transfer phenomenon in a rigid and opaque body that exchanges energy, with the environment, by convection and by diffuse thermal radiation is studied. The considered phenomenon is described by a partial differential equation, subjected to (nonlinear) boundary conditions. A minimum principle, suitable for a large class of energy transfer problems is presented. Some particular cases are simulated. (author)

  13. Evidence for an unorthodox firing sequence employed by the Berlin Painter : deciphering ancient ceramic firing conditions through high-resolution material characterization and replication

    NARCIS (Netherlands)

    Cianchetta, I.; Trentelman, K.; Maish, J.; Saunders, D.; Foran, B.; Walton, M.; Sciau, Ph.; Wang, T.; Pouyet, E.; Cotte, M.; Meirer, F.; Liu, Y.; Pianetta, P.; Mehta, A.

    2015-01-01

    XANES spectroscopy was used to complement the results previously obtained with Raman spectroscopy by the same group to determine the firing conditions used in the production of a single vessel painted by the Berlin Painter in the 5th century B.C. The vessel, part of the collection of the J. Paul

  14. Optimization of conditions for fish and power production in Surna, Moere and Romsdal. Report from phase 1 concerning development and employment of simulation tool from Rinna to Skei

    International Nuclear Information System (INIS)

    Halleraker, Jo Halvard; Sundt, Haakon; Alfredsen, Knut T.

    2006-04-01

    A documentation of the current and previous physical conditions in the regulated part of the river Surna (Norway) is provided. Focus is on power production's negative impact on young salmon. Recommendations are addressed to Statkraft in order to reduce the negative impact. Four problems significant for the salmon habitat are identified: 1. Swift water level dips, especially early in growth season and daytime in the middle of the winter, cause a significant amount of stranded fish. 2. A change in the temperature regime downstream in Trollheim power plant because of bottom drainage of Follsjoe, lowering the water temperature in large parts of Surna in the summer and increasing it in the winter. 3. Periodical low water and marginal habitat conditions in Surna above the discharge of the power plant. 4. Reduction of hiding places and tightening of cavities because of reduced intensity and duration of floods. Proposed actions and sketches for solutions are provided in the analysis (ml)

  15. In vitro testing of drug combinations employing nilotinib and alkylating agents with regard to pretransplant conditioning treatment of advanced-phase chronic myeloid leukemia.

    Science.gov (United States)

    Radujkovic, Aleksandar; Luft, Thomas; Dreger, Peter; Ho, Anthony D; Jens Zeller, W; Fruehauf, Stefan; Topaly, Julian

    2014-08-01

    The prognosis of patients with advanced-phase chronic myeloid leukemia (CML) remains dismal despite the availability of targeted therapies and allogeneic stem cell transplantation (allo-SCT). Increasing the antileukemic efficacy of the pretransplant conditioning regimen may be a strategy to increase remission rates and duration. We therefore investigated the antiproliferative effects of nilotinib in combination with drugs that are usually used for conditioning: the alkylating agents mafosfamide, treosulfan, and busulfan. Drug combinations were tested in vitro in different imatinib-sensitive and imatinib-resistant BCR-ABL-positive cell lines. A tetrazolium-based MTT assay was used for the assessment and quantification of growth inhibition after exposure to alkylating agents alone or to combinations with nilotinib. Drug interaction was analyzed using the median-effect method of Chou and Talalay, and combination index (CI) values were calculated according to the classic isobologram equation. Treatment of imatinib-sensitive, BCR-ABL-positive K562 and LAMA84 cells with nilotinib in combination with mafosfamide, treosulfan, or busulfan resulted in synergistic (CI 1) effects, respectively. In imatinib-resistant K562-R and LAMA84-R cells, all applied drug combinations were synergistic (CI conditioning regimens for allo-SCT in advanced-phase CML.

  16. MHD Heat and Mass Transfer of Chemical Reaction Fluid Flow over a Moving Vertical Plate in Presence of Heat Source with Convective Surface Boundary Condition

    Directory of Open Access Journals (Sweden)

    B. R. Rout

    2013-01-01

    Full Text Available This paper aims to investigate the influence of chemical reaction and the combined effects of internal heat generation and a convective boundary condition on the laminar boundary layer MHD heat and mass transfer flow over a moving vertical flat plate. The lower surface of the plate is in contact with a hot fluid while the stream of cold fluid flows over the upper surface with heat source and chemical reaction. The basic equations governing the flow, heat transfer, and concentration are reduced to a set of ordinary differential equations by using appropriate transformation for variables and solved numerically by Runge-Kutta fourth-order integration scheme in association with shooting method. The effects of physical parameters on the velocity, temperature, and concentration profiles are illustrated graphically. A table recording the values of skin friction, heat transfer, and mass transfer at the plate is also presented. The discussion focuses on the physical interpretation of the results as well as their comparison with previous studies which shows good agreement as a special case of the problem.

  17. Influence of reaction conditions and the char separation system on the production of bio-oil from radiata pine sawdust by fast pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hyun Ju; Park, Young-Kwon; Kim, Joo Sik [Faculty of Environmental Engineering, University of Seoul, 90 Jeonnong-Dong, Dondaemun-Gu, Seoul 130-743 (Korea)

    2008-08-15

    Radiata pine sawdust was pyrolyzed in a bubbling fluidized bed equipped with a char separation system. The influence of the reaction conditions on the production of bio-oil was investigated through the establishment of mass balance, and the examination of the products' chemical and physical characteristics. The optimal reaction temperature for the production of bio-oil was between 673 and 723 K, and the yield was above 50 wt.% of the product. An optimal feed size also existed. In a particle with a size that was less than 0.3 mm, the bio-oil yield decreased due to overheating, which led to gas formation. A higher flow rate and feeding rate were found to be more effective for the production of bio-oil, but did not significantly affect it. The main compounds of bio-oil were phenolics, including cresol, guaiacol, eugenol, benzendiol and their derivatives, ketones, and aldehydes. In addition, high-quality bio-oils, which contained less than 0.005 wt.% of solid, no ash and low concentrations of alkali and alkaline earth metals, were produced due to the char removal system. (author)

  18. Fabrication of hollow carbon nanospheres introduced with Fe and N species immobilized palladium nanoparticles as catalysts for the semihydrogenation of phenylacetylene under mild reaction conditions

    Science.gov (United States)

    Zhang, Wei; Wang, Fushan; Li, Xinlin; Liu, Yansheng; Liu, Yang; Ma, Jiantai

    2017-05-01

    Palladium nanoparticles immobilized on hollow carbon nanospheres introduced with both Fe and N species, denoted as Pd/Fe-N/C, have been designed as an efficient, heterogeneous, environmentally friendly catalyst for the semihydrogenation of phenylacetylene in liquid-phase under mild conditions (298 K, H2 1 atm) without any additive. A high selectivity towards styrene (higher than 96.2%) was achieved with the total conversion of phenylacetylene within 80 min. The synergistic effect of doped N and Fe with Pd might be an important influence on improving the catalytic performance. Moreover, the Pd/Fe-N/C could be easily recycled by centrifugation and is reusable without obvious decrease of catalytic activity and selectivity. Therefore, the Pd/Fe-N/C nanocatalyst is highly attractive as selective hydrogenation heterogeneous catalyst for important industrial reactions.

  19. Employing the International Classification of Functioning, Disability and Health to enhance services for children and youth with chronic physical health conditions and disabilities.

    Science.gov (United States)

    McDougall, Janette; Horgan, Karen; Baldwin, Patricia; Tucker, Mary Ann; Frid, Pamela

    2008-03-01

    In 2001, the World Health Organization published the International Classification of Functioning, Disability and Health (ICF). The ICF is just beginning to be used in a variety of clinical and research settings in Canada and worldwide. The purpose of the present article is to describe the initial use of the ICF at an Ontario children's rehabilitation centre, and to consider further uses both within and outside the centre for enhancing services for children and youth with chronic physical health conditions and disabilities, as well as for their families. A description is provided on how the ICF has been used at the centre to guide clinical thinking and practice, and to justify and steer research directions. Plans underway to use the ICF to collect and record functional data at the centre are also described. Finally, recommendations for the use of the ICF to enhance communication among child health professionals across service settings are provided. Used in conjunction with the International Classification of Diseases - Tenth Revision, the ICF's conceptual framework and classification system shows great promise for enhancing the quality of services for children with chronic conditions and their families. This information may assist paediatric specialists, other child health professionals, researchers and administrators to use the ICF in similar settings. It may also stimulate exploration of the use of the ICF for general paediatricians and other service providers in the larger community.

  20. A possibility of parallel and anti-parallel diffraction measurements on neu- tron diffractometer employing bent perfect crystal monochromator at the monochromatic focusing condition

    Science.gov (United States)

    Choi, Yong Nam; Kim, Shin Ae; Kim, Sung Kyu; Kim, Sung Baek; Lee, Chang-Hee; Mikula, Pavel

    2004-07-01

    In a conventional diffractometer having single monochromator, only one position, parallel position, is used for the diffraction experiment (i.e. detection) because the resolution property of the other one, anti-parallel position, is very poor. However, a bent perfect crystal (BPC) monochromator at monochromatic focusing condition can provide a quite flat and equal resolution property at both parallel and anti-parallel positions and thus one can have a chance to use both sides for the diffraction experiment. From the data of the FWHM and the Delta d/d measured on three diffraction geometries (symmetric, asymmetric compression and asymmetric expansion), we can conclude that the simultaneous diffraction measurement in both parallel and anti-parallel positions can be achieved.

  1. The impact of raw materials and baking conditions on Maillard reaction products, thiamine, folate, phytic acid and minerals in white bread.

    Science.gov (United States)

    Helou, Cynthia; Gadonna-Widehem, Pascale; Robert, Nathalie; Branlard, Gérard; Thebault, Jacques; Librere, Sarah; Jacquot, Sylvain; Mardon, Julie; Piquet-Pissaloux, Agnès; Chapron, Sophie; Chatillon, Antoine; Niquet-Léridon, Céline; Tessier, Frédéric J

    2016-06-15

    The aim of this study was to develop a white bread with improved nutrient contents and reduced levels of potentially harmful Maillard reaction products such as N(ε)-carboxymethyllysine (CML) and 5-hydroxymethylfurfural (HMF). Assays were carried out through a full factorial experimental design allowing the simultaneous analysis of four factors at two levels: (1) wheat flour extraction rates (ash content: 0.60%-0.72%), (2) leavening agents (bakers' yeast - bakers' yeast and sourdough), (3) prebaking and (4) baking conditions (different sets of time and temperature). The baking conditions affected HMF and CML as well as certain mineral contents. A reduced baking temperature along with a prolonged heat treatment was found to be favourable for reducing both the CML (up to 20%) and HMF concentrations (up to 96%). The presence of sourdough decreased the formation of CML (up to 28%), and increased the apparent amounts of calcium (up to 8%) and manganese (up to 17.5%) probably through acidification of the dough. The extraction rate of flours as well as interactions between multiple factors also affected certain mineral content. However, compounds like folate, thiamine, copper, zinc, iron and phytic acid were not affected by any of the factors studied.

  2. Reducing Employment Insecurity

    Directory of Open Access Journals (Sweden)

    Florence Lebert

    2016-10-01

    Full Text Available The perception of job insecurity is known to be a stressful condition for employees. Less is known about employment insecurity and the ways employees and their families deal with it. This study investigates whether participation in further training is a strategy that employees adopt to reduce perceived employment insecurity. As participation in further training is often costly and time-consuming, we assume that the family context is of importance for the decision to take part in further training. To take account of possible self-selection, we apply a propensity score matching procedure on longitudinal data from the Swiss Household Panel (2004-2013. Three main findings can be emphasized: first, participation in further training is not a strategy adopted particularly by employees who perceive high employment insecurity as they are less likely to train than their secure counterparts. Second, even though further training is not a strategy that is actively adopted, employees who train subsequently report lower levels of perceived employment insecurity. Third, the family context indeed influences the likelihood to train: partnered employees are more likely to train and preschool-aged children act as a constraint on women’s but enhance men’s participation in further training. Yet, in the context of high perceived employment insecurity, children generally reduce their parents’ likelihood to train as the parents may turn to other strategies that reduce perceived employment insecurity.

  3. Working conditions as predictors of retirement intentions and exit from paid employment: a 10-year follow-up of the English Longitudinal Study of Ageing.

    Science.gov (United States)

    Carr, Ewan; Hagger-Johnson, Gareth; Head, Jenny; Shelton, Nicola; Stafford, Mai; Stansfeld, Stephen; Zaninotto, Paola

    Population ageing in Western countries has made delayed retirement and extended working life a policy priority in recent years. Retirement timing has been linked to individual factors such as health and wealth, but less is known about the role of the psychosocial work environment. This paper drew upon longitudinal data on 3462 workers aged 50-69 from five waves of the English Longitudinal Study of Ageing (ELSA). Regression models were used to assess the association of working conditions with preferred timing of retirement and actual work exit. Adjusting for a range of covariates, job demands (aspects of the job requiring sustained physical or psychological effort) were associated with preferences for earlier retirement (by 0.18 years; 95 % C.I. 0.06, 0.31). Decision authority was associated with preferences for later retirement (by 0.38 years; 95 % C.I. 0.23, 0.53) and reduced odds of work exit (OR = 0.93; 95 % C.I. 0.88, 0.97). Low recognition at work was associated with increased odds of work exit (OR = 1.23; 95 % C.I. 1.10, 1.43). There was little evidence of any interactive relationship between demands and resources. Efforts to extend working life should address issues relating to the immediate psychosocial work environment. Providing older workers with increased sense of control, and ensuring contributions are adequately recognised, may delay retirement intentions and the timing of labour market exit.

  4. Employment relations, flexibility and risk

    DEFF Research Database (Denmark)

    Jensen, Carsten Strøby

    Employment relations literature often distinguishes between social democratic/corporatist models of employment relations and liberal models of employment relations as they are seen as opposite or at least different ways of organizing labor markets. They are often characterized as having very...... different risk profiles in terms of relationships between employees, employers, and the state. Low levels of labor market regulation very often characterize the liberal models of employment relations as we know them from, for instance, the USA and the UK. This means that employment conditions are very often...... insecure and that the burden of unemployment risk mostly lies with the employees rather than the employer. Corporatist – or social democratic – employment relations models are, in contrast to the liberal models, often characterized by stricter regulation of the labor market and by high standards...

  5. Flow Giese reaction using cyanoborohydride as a radical mediator

    Directory of Open Access Journals (Sweden)

    Takahide Fukuyama

    2013-09-01

    Full Text Available Tin-free Giese reactions, employing primary, secondary, and tertiary alkyl iodides as radical precursors, ethyl acrylate as a radical trap, and sodium cyanoborohydride as a radical mediator, were examined in a continuous flow system. With the use of an automated flow microreactor, flow reaction conditions for the Giese reaction were quickly optimized, and it was found that a reaction temperature of 70 °C in combination with a residence time of 10–15 minutes gave good yields of the desired addition products.

  6. Nitric Oxide Reduction by Carbon Monoxide over Supported Hexaruthenium Cluster Catalysts. 1. The Active Site Structure That Depends on Supporting Metal Oxide and Catalytic Reaction Conditions.

    Science.gov (United States)

    Minato, Taketoshi; Izumi, Yasuo; Aika, Ken-Ichi; Ishiguro, Atsushi; Nakajima, Takayuki; Wakatsuki, Yasuo

    2003-08-28

    Ruthenium site structures supported on metal oxide surfaces were designed by reacting organometallic Ru cluster [Ru6C(CO)16](2-) or [Ru6(CO)18](2-) with various metal oxides, TiO2, Al2O3, MgO, and SiO2. The surface Ru site structure, formed under various catalyst preparation and reaction conditions, was investigated by the Ru K-edge extended X-ray absorption fine structure (EXAFS). Samples of [Ru6C(CO)16](2-)/TiO2(anatase) and [Ru6C(CO)16](2-)/TiO2(rutile) were found to retain the original Ru6C framework when heated in the presence of NO (2.0 kPa) or NO (2.0 kPa) + CO (2.0 kPa) at 423 K, i.e., catalytic reaction conditions for NO decomposition. At 523 K, the Ru-Ru bonds of the Ru6C framework were cleaved by the attack of NO. In contrast, the Ru site became spontaneously dispersed over TiO2 (anatase). When being supported over TiO2 (mesoporous), MgO, or Al2O3, the Ru6C framework split into fragments in gaseous NO or NO + CO even at 423 K. The Ru6 framework of [Ru6(CO)18](2-) was found to break easily into smaller ensembles in the presence of NO and/or CO at 423 K on support. Taking into consideration the realistic environments in which these catalysts will be used, we also examined the effect of water and oxygen. When water was introduced to the sample [Ru6C(CO)16](2-)/TiO2(anatase) at 423 K, it did not have any effects on the stabilized Ru6C framework structure. In the presence of oxygen gas, however, the Ru hexanuclear structure decomposed into isolated Ru cations bound to surface oxygen atoms of TiO2 (anatase).

  7. Reaction of subsurface coastal aquifers to climate and land use changes in Greece: modelling of groundwater refreshening patterns under natural recharge conditions

    Science.gov (United States)

    Lambrakis, N.; Kallergis, G.

    2001-05-01

    This paper studies the multicomponent ion exchange process and freshening time under natural recharge conditions for three coastal aquifers in Greece. Due to over-pumping and the dry years of 1980-1990 decline in groundwater quality has been observed in most of the Greek coastal aquifers. This decline is caused by a lack of reliable water resource management, water abstraction from great depths, and seawater intrusion resulting in a rise of the fresh/salt water interface (salinisation process) due to a negative water balance. The reverse phenomenon, which should lead to groundwater freshening, is a long process. The freshening process shows chromatographic patterns that are due to chemical reactions such as calcite dissolution and cation exchange, and simultaneously occurring transport and dispersion processes. Using the geochemical simulation codes PHREEQE and PHREEQM (Parkhurst et al., US Geol. Surv. Water Resour. Invest., 80-96 (1980) 210; Appelo and Postma, Geochemistry, Groundwater and Pollution (1994)), these patterns were analysed and the above-mentioned processes were simulated for carefully selected aquifers in Peloponnesus and Crete (Greece). Aquifers of the Quaternary basin of Glafkos in Peloponnesus, the Neogene formations in Gouves, Crete, and the carbonate aquifer of Malia, Crete, were examined as representative examples of Greek coastal aquifer salinisation. The results show that when pumping was discontinued, the time required for freshening under natural conditions of the former two aquifers is long and varies between 8000 and 10,000 years. The Malia aquifer on the other hand, has a freshening time of 15 years. Freshening time was shown to depend mainly on cation exchange capacities and the recharge rate of the aquifers.

  8. Effects of heat-moisture treatment reaction conditions on the physicochemical and structural properties of maize starch: moisture and length of heating.

    Science.gov (United States)

    Sui, Zhongquan; Yao, Tianming; Zhao, Yue; Ye, Xiaoting; Kong, Xiangli; Ai, Lianzhong

    2015-04-15

    Changes in the properties of normal maize starch (NMS) and waxy maize starch (WMS) after heat-moisture treatment (HMT) under various reaction conditions were investigated. NMS and WMS were adjusted to moisture levels of 20%, 25% and 30% and heated at 100 °C for 2, 4, 8 and 16 h. The results showed that moisture content was the most important factor in determining pasting properties for NMS, whereas the heating length was more important for WMS. Swelling power decreased in NMS but increased in WMS, and while the solubility index decreased for both samples, the changes were largely determined by moisture content. The gelatinisation temperatures of both samples increased with increasing moisture content but remained unchanged with increasing heating length. The Fourier transform infrared (FT-IR) absorbance ratio was affected to different extents by the moisture levels but remained constant with increasing the heating length. The X-ray intensities increased but relative crystallinity decreased to a greater extent with increasing moisture content. This study showed that the levels of moisture content and length of heating had significant impacts on the structural and physicochemical properties of normal and waxy maize starches but to different extents. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Hidden Hydride Transfer as a Decisive Mechanistic Step in the Reactions of the Unligated Gold Carbide [AuC]+ with Methane under Ambient Conditions.

    Science.gov (United States)

    Li, Jilai; Zhou, Shaodong; Schlangen, Maria; Weiske, Thomas; Schwarz, Helmut

    2016-10-10

    The reactivity of the cationic gold carbide [AuC] + (bearing an electrophilic carbon atom) towards methane has been studied using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). The product pairs generated, that is, Au + /C 2 H 4 , [Au(C 2 H 2 )] + /H 2 , and [C 2 H 3 ] + /AuH, point to the breaking and making of C-H, C-C, and H-H bonds under single-collision conditions. The mechanisms of these rather efficient reactions have been elucidated by high-level quantum-chemical calculations. As a major result, based on molecular orbital and NBO-based charge analysis, an unprecedented hydride transfer from methane to the carbon atom of [AuC] + has been identified as a key step. Also, the origin of this novel mechanistic scenario has been addressed. The mechanistic insights derived from this study may provide guidance for the rational design of carbon-based catalysts. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. A Numerical Handling of the Boundary Conditions Imposed by the Skull on an Inhomogeneous Diffusion-Reaction Model of Glioblastoma Invasion Into the Brain: Clinical Validation Aspects

    Directory of Open Access Journals (Sweden)

    Georgios S Stamatakos

    2017-01-01

    Full Text Available A novel explicit triscale reaction-diffusion numerical model of glioblastoma multiforme tumor growth is presented. The model incorporates the handling of Neumann boundary conditions imposed by the cranium and takes into account both the inhomogeneous nature of human brain and the complexity of the skull geometry. The finite-difference time-domain method is adopted. To demonstrate the workflow of a possible clinical validation procedure, a clinical case/scenario is addressed. A good agreement of the in silico calculated value of the doubling time (ie, the time for tumor volume to double with the value of the same quantity based on tomographic imaging data has been observed. A theoretical exploration suggests that a rough but still quite informative value of the doubling time may be calculated based on a homogeneous brain model. The model could serve as the main component of a continuous mathematics-based glioblastoma oncosimulator aiming at supporting the clinician in the optimal patient-individualized design of treatment using the patient’s multiscale data and experimenting in silico (ie, on the computer.

  11. Employment status, employment functioning, and barriers to employment among VA primary care patients.

    Science.gov (United States)

    Zivin, Kara; Yosef, Matheos; Levine, Debra S; Abraham, Kristen M; Miller, Erin M; Henry, Jennifer; Nelson, C Beau; Pfeiffer, Paul N; Sripada, Rebecca K; Harrod, Molly; Valenstein, Marcia

    2016-03-15

    Prior research found lower employment rates among working-aged patients who use the VA than among non-Veterans or Veterans who do not use the VA, with the lowest reported employment rates among VA patients with mental disorders. This study assessed employment status, employment functioning, and barriers to employment among VA patients treated in primary care settings, and examined how depression and anxiety were associated with these outcomes. The sample included 287 VA patients treated in primary care in a large Midwestern VA Medical Center. Bivariate and multivariable analyses were conducted examining associations between socio-demographic and clinical predictors of six employment domains, including: employment status, job search self-efficacy, work performance, concerns about job loss among employed Veterans, and employment barriers and likelihood of job seeking among not employed Veterans. 54% of respondents were employed, 36% were not employed, and 10% were economically inactive. In adjusted analyses, participants with depression or anxiety (43%) were less likely to be employed, had lower job search self-efficacy, had lower levels of work performance, and reported more employment barriers. Depression and anxiety were not associated with perceived likelihood of job loss among employed or likelihood of job seeking among not employed. Single VA primary care clinic; cross-sectional study. Employment rates are low among working-aged VA primary care patients, particularly those with mental health conditions. Offering primary care interventions to patients that address mental health issues, job search self-efficacy, and work performance may be important in improving health, work, and economic outcomes. Published by Elsevier B.V.

  12. Evaluating Employability Skills: Employer and Student Perceptions

    Science.gov (United States)

    Saunders, Venetia; Zuzel, Katherine

    2010-01-01

    Graduate employability is a key issue for Higher Education. In this two-part study student employability skills have been evaluated from the perspective of sandwich students and graduates in biomolecular science, and their employers. A strong correlation was found between employer and sandwich student/graduate perceptions of the relative…

  13. Photocatalytic fluoroalkylation reactions of organic compounds

    OpenAIRE

    Barata Vallejo, Sebastian; Bonesi, Sergio Mauricio; Postigo, Jose Alberto

    2017-01-01

    Photocatalytic methods for fluoroalkyl-radical generation provide more convenient alternatives to the classical perfluoroalkyl-radical (Rf) production through chemical initiators, such as azo or peroxide compounds or the employment of transition metals through a thermal electron transfer (ET) initiation process. The mild photocatalytic reaction conditions tolerate a variety of functional groups and, thus, are handy to the late-stage modification of bioactive molecules. Transition metal-photoc...

  14. Biomaterial Encapsulation Is Enhanced in the Early Stages of the Foreign Body Reaction During Conditional Macrophage Depletion in Transgenic Macrophage Fas-Induced Apoptosis Mice

    NARCIS (Netherlands)

    Bank, Ruud A.; Zandstra, Jurjen; Room, Hilde; Petersen, Arjen H.; van Putten, Sander M.

    2017-01-01

    Macrophages are pivotal cells during the foreign body reaction (FBR), as they orchestrate the proinflammatory microenvironment inside and around biomaterials by secretion of inflammatory mediators. Furthermore, they are responsible for the degradation of biomaterials and are thought to instruct the

  15. New Insight into the Hydrogen Evolution Reaction under Buffered Near-Neutral pH Conditions: Enthalpy and Entropy of Activation

    KAUST Repository

    Shinagawa, Tatsuya; Takanabe, Kazuhiro

    2016-01-01

    performance was summarized with respect to the binding energy of the reaction intermediate species, a classic volcano-shaped relationship was obtained. Interestingly, the temperature sensitivity analysis disclosed that smaller activation energies did

  16. Piper-betle-shaped nano-S-catalyzed synthesis of 1-amidoalkyl-2-naphthols under solvent-free reaction condition: a greener "nanoparticle-catalyzed organic synthesis enhancement" approach.

    Science.gov (United States)

    Das, Vijay K; Borah, Madhurjya; Thakur, Ashim J

    2013-04-05

    Nano-S prepared by an annealing process showed excellent catalytic activity for the synthesis of 1-amidoalkyl-2-naphthols under solvent-free reaction condition at 50 °C. The catalyst could be reused up to the fifth cycle without loss in its action. The green-ness of the present protocol was also measured using green metrics drawing its superiority.

  17. Employment specialist competencies for supported employment programs

    NARCIS (Netherlands)

    Corbière, M.; Brouwers, E.P.M.; Lanctôt, N.; van Weeghel, J.

    2014-01-01

    Purpose Supported employment (SE) programs are evidence-based programs offered to people with severe mental illness to facilitate obtaining and keeping competitive work. However, significant variations in individuals’ vocational success may be partly explained by differences in their employment

  18. Study of reactional conditions of oxidative cleavage reaction of bicyclic {beta}-hydroxy ethers promoted by ruthenium tetroxide; Estudo das condicoes reacionais da reacao de clivagem oxidativa de {beta}-hidroxi eteres biciclicos promovida por tetroxido de rutenio

    Energy Technology Data Exchange (ETDEWEB)

    Ferraz, Helena M.C.; Scalfo, Alexsandra C. [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Quimica; Vilalba, Bruno T.; Longo Junior, Luiz S., E-mail: luiz.longo@unifesp.b [Universidade Federal de Sao Paulo (UNIFESP-EPM), Diadema, SP (Brazil)

    2010-07-01

    A systematic study of the reaction of {beta}-hydroxy ethers with ruthenium tetraoxide (RuO{sub 4}), generated in situ from ruthenium trichloride and sodium periodate, is presented, leading to nine-membered ring keto-lactones in moderate yields. Three different solvent systems - AcOEt/MeCN/H{sub 2}O, MeCN/H{sub 2}O and DMC/H{sub 2}O - were studied leading to the desired products in lower yields than those obtained with the classical mixture of CCl{sub 4}/MeCN/H{sub 2}O, commonly used in reactions promoted by this oxidant. However, it is noteworthy that these new solvent systems represent greener alternatives to the chlorinated solvents used in the oxidative cleavage of {beta}-hydroxy ethers by RuO{sub 4}. (author)

  19. Energy investments and employment

    International Nuclear Information System (INIS)

    1993-08-01

    A study was conducted to assess the effect that different energy options would have on provincial and regional employment prospects in British Columbia. Current and future economic and employment patterns were examined to develop a more detailed understanding of the skills, age, gender, location, and other characteristics of British Columbia workers. Over 40 previous studies examining the energy/employment relationship were also reviewed. Based on this review and an analysis of the province's economic and labor conditions, the following conclusions are drawn. Investment in non-energy sectors offers better prospects for reducing unemployment than investment in the energy sector, whether for new supply or improving efficiency. Investments in the energy sector provide fewer jobs than investments in most other sectors of the economy. Among the available electricity supply options, large hydroelectric projects tend to produce the fewest jobs per investment dollar. Smaller thermal projects such as wood residue plants produce the most jobs. If and when more energy is needed in British Columbia, the most cost-effective combination of energy supply and efficiency options will also create the most jobs. Compared to traditional energy supply options, investments in energy efficiency would create about twice as many total jobs, create jobs that better match the skills of the province's unemployed and its population distribution, and create jobs that last longer on the average. Construction-related measures such as improved insulation tend to produce more jobs per investment dollar than the substitution of more energy-efficient equipment. 69 refs., 9 tabs

  20. Exact criteria for uniqueness and multiplicity of an nth order chemical reaction via catastrophe theory approach. [Determines boundaries between unique and multiple steady state conditions

    Energy Technology Data Exchange (ETDEWEB)

    Chang, H C; Calo, J M

    1979-01-01

    A simple, generalized technique for the exact determination of the boundaries between regions of unique and of multiple solutions to certain nonlinear equations was developed by applying catastrophe theory to the mapping of implicit and explicit functions. Its application to an nth order reaction in continuous stirred tank reactor (CSTR) yields exact, explicit expressions for the boundaries between regions of single and multiple steady states, expressed in terms of the dimensionless heat transfer coefficient and activation energy. An exact implicit expression for the boundaries between regions of uniqueness and multiplicity was also derived for an nth order reaction in a catalyst particle with an intraparticle concentration gradient and uniform temperature and is fully demonstrated for the first-order reaction. In addition, explicit criteria were developed by assuming the limits on d ln g/d ln q, where g is the effectiveness factor and q the Thiele modulus, proposed by van den Bosch and Luss.

  1. Design, development, and demonstration of a fully LabVIEW controlled in situ electrochemical Fourier transform infrared setup combined with a wall-jet electrode to investigate the electrochemical interface of nanoparticulate electrocatalysts under reaction conditions.

    Science.gov (United States)

    Nesselberger, Markus; Ashton, Sean J; Wiberg, Gustav K H; Arenz, Matthias

    2013-07-01

    We present a detailed description of the construction of an in situ electrochemical ATR-FTIR setup combined with a wall-jet electrode to investigate the electrocatalytic properties of nanoparticulate catalysts in situ under controlled mass transport conditions. The presented setup allows the electrochemical interface to be probed in combination with the simultaneous determination of reaction rates. At the same time, the high level of automation allows it to be used as a standard tool in electrocatalysis research. The performance of the setup was demonstrated by probing the oxygen reduction reaction on a platinum black catalyst in sulfuric electrolyte.

  2. Cu catalyzed oxidation of 5-hydroxymethylfurfural to 2,5-diformylfuran and 2,5-furandicarboxylic acid under benign reaction conditions

    DEFF Research Database (Denmark)

    Hansen, Thomas S.; Sádaba, Irantzu; Garcia, Eduardo

    2013-01-01

    containing promoters (NCPs) to obtain excellent yields. In acetonitrile a 95% DFF yield was obtained after 24h with ambient pressure of dioxygen at room temperature in the presence of different NCPs, which – to our knowledge – is the best result reported thus far for this reaction. The use of NCPs made...... it further possible to apply various traditional solvents, e.g. acetone, methanol and methyl isobutyl ketone for the reaction. The latter can be used as extraction solvent for HMF synthesis in aqueous media and thus integrate the two processes. Additionally, HMF was oxidized to 2,5-furandicarboxylic acid...

  3. Reaction Qualifications Revisited

    DEFF Research Database (Denmark)

    Lippert-Rasmussen, Kasper

    2009-01-01

      When, in a competitive sphere, people are selected on the basis of qualifications only, their chances of acquiring positions of advantage may seem to depend entirely upon their abilities, not discriminatory bias. However, if reaction qualifications - i.e. characteristics which contribute...... to a person's effectiveness by causing a favourable reaction in customers, co-workers etc. (for short: recipients) - are involved, this assumption is false. Building on work by Wertheimer, Mason, and Miller, this paper proposes an account of the reaction qualifications that count, from the point of view...... of merit. Specifically, it preserves symmetry between negative evaluations of antimeritocratic bases of selection and negative evaluations of qualifications rooted in comparable antimeritocratic reactions. So if employers should not select among applicants on the basis of their (the employers') racial...

  4. Additional employer and employee obligations of the contract of employment

    OpenAIRE

    Jankauskaitė, Vaida

    2009-01-01

    Economic growth since 2001 till 2008 start leaded to higher incomes for both employers and employees, many new jobs were created. The unemployment rate in Lithuania was particularly low, moreover, according to official statistics, nearly half a million people emigrated from Lithuania. Labor market challenges and economic patterns determined the principles of the labor law and the content of the norms, public social and political conditions. Employers, through businesses, noticed that it has b...

  5. Influence of catalytic activity and reaction conditions on the product distribution in coal liquefaction; Sekitan ekikayu no seiseibutsu bunpu ni taisuru shokubai kassei oyobi hanno joken no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Hasuo, H.; Sakanishi, K.; Mochida, I. [Kyushu University, Fukuoka (Japan). Institute of Advanced Material Study

    1996-10-28

    The NiMo sulfide supported on Ketjen Black (KB) was more effective and yielded lighter oil products containing light fractions with their boiling point below 300{degree}C during the two stage liquefaction combining low temperature and high temperature hydrogenation the conventional NiMo/alumina catalyst and FeS2 catalyst. Although the NiMo/alumina yielded increased oil products during the two stage liquefaction, the lighter oil fractions did not increase and the heavier fractions increased mainly. This suggests that the hydrogenation of aromatic rings and successive cleavage of the rings are necessary for producing the light oil, which is derived from the sufficient hydrogenation of aromatic rings using catalysts. For the two stage reaction with NiMo/KB catalyst, it was considered that sufficient hydrogen was directly transferred to coal molecules at the first stage of the low temperature reaction, which promoted the solubilization of coal and the successive hydrogenation at the high temperature reaction. Thus, high activity of the catalyst must be obtained. It is expected that further high quality distillates can be produced through the optimization of catalysts and solvents at the two stage reaction. 1 ref., 4 figs., 1 tab.

  6. Connecting the dots: Semi-analytical and random walk numerical solutions of the diffusion–reaction equation with stochastic initial conditions

    Energy Technology Data Exchange (ETDEWEB)

    Paster, Amir, E-mail: paster@tau.ac.il [Environmental Fluid Mechanics Laboratories, Dept. of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN (United States); School of Mechanical Engineering, Tel Aviv University, Tel Aviv, 69978 (Israel); Bolster, Diogo [Environmental Fluid Mechanics Laboratories, Dept. of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN (United States); Benson, David A. [Hydrologic Science and Engineering, Colorado School of Mines, Golden, CO, 80401 (United States)

    2014-04-15

    We study a system with bimolecular irreversible kinetic reaction A+B→∅ where the underlying transport of reactants is governed by diffusion, and the local reaction term is given by the law of mass action. We consider the case where the initial concentrations are given in terms of an average and a white noise perturbation. Our goal is to solve the diffusion–reaction equation which governs the system, and we tackle it with both analytical and numerical approaches. To obtain an analytical solution, we develop the equations of moments and solve them approximately. To obtain a numerical solution, we develop a grid-less Monte Carlo particle tracking approach, where diffusion is modeled by a random walk of the particles, and reaction is modeled by annihilation of particles. The probability of annihilation is derived analytically from the particles' co-location probability. We rigorously derive the relationship between the initial number of particles in the system and the amplitude of white noise represented by that number. This enables us to compare the particle simulations and the approximate analytical solution and offer an explanation of the late time discrepancies. - Graphical abstract:.

  7. CO oxidation on PtSn nanoparticle catalysts occurs at the interface of Pt and Sn oxide domains formed under reaction conditions

    KAUST Repository

    Michalak, William D.; Krier, James M.; Alayoglu, Selim; Shin, Jae-Yoon; An, Kwangjin; Komvopoulos, Kyriakos; Liu, Zhi; Somorjai, Gabor A.

    2014-01-01

    The barrier to CO oxidation on Pt catalysts is the strongly bound adsorbed CO, which inhibits O2 adsorption and hinders CO2 formation. Using reaction studies and in situ X-ray spectroscopy with colloidally prepared, monodisperse ∼2 nm Pt and PtSn

  8. CATALYST-FREE REACTIONS UNDER SOLVENT-FEE CONDITIONS: MICROWAVE-ASSISTED SYNTHESIS OF HETEROCYCLIC HYDRAZONES BELOW THE MELTING POINT OF NEAT REACTANTS

    Science.gov (United States)

    The reaction of neat 5- or 8-oxobenzopyran-2(1H)-ones with a variety of aromatic and heteroaromatic hydrazines are remarkable accelerated upon irradiation in a household microwave oven in the absence of any catalyst, solid support or solvent thus providing an environmentally frie...

  9. Optimization of reaction conditions in selective oxidation of styrene over fine crystallite spinel-type CaFe2O4 complex oxide catalyst

    International Nuclear Information System (INIS)

    Pardeshi, Satish K.; Pawar, Ravindra Y.

    2010-01-01

    The CaFe 2 O 4 spinel-type catalyst was synthesized by citrate gel method and well characterized by thermogravimetric analysis, atomic absorption spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffraction and transmission electron microscopy. The crystallization temperature of the spinel particle prepared by citrate gel method was 600 o C which was lower than that of ferrite prepared by other methods. CaFe 2 O 4 catalysts prepared by citrate gel method show better activity for styrene oxidation in the presence of dilute H 2 O 2 (30%) as an oxidizing agent. In this reaction the oxidative cleavage of carbon-carbon double bond of styrene takes place selectively with 38 ± 2 mol% conversion. The major product of the reaction is benzaldehyde up to 91 ± 2 mol% and minor product phenyl acetaldehyde up to 9 ± 2 mol%, respectively. The products obtained in the styrene oxidation reaction were analyzed by gas chromatography and mass spectroscopy. The influence of the catalyst, reaction time, temperature, amount of catalyst, styrene/H 2 O 2 molar ratio and solvents on the conversion and product distribution were studied.

  10. Equilibrium coverage of OHad in correlation with platinum catalyzed fuel cell reactions in HClO4

    DEFF Research Database (Denmark)

    Deng, Yujia; Arenz, Matthias; Wiberg, Gustav Karl Henrik

    2015-01-01

    We employ a recently developed stripping protocol to examine the equilibrium coverage of oxygenated species and their influence on the oxygen reduction reaction (ORR) and the hydrogen oxidation reaction (HOR). In particular we aim to distinguish between dynamic and steady state conditions...

  11. The Effect of Cooling Vest on Heat Strain Indexes and Reaction Time While Wearing Chemical-Microbial-Radioactive Protective Clothing in Hot and Dry Laboratory Conditions

    Directory of Open Access Journals (Sweden)

    Dehghan

    2016-09-01

    Full Text Available Background Heat is a harmful factor in workplaces that causes physiologic and cognitive changes in workers. Objectives The purpose of this study was to investigate the effect of cooling vest on heat strain and reaction time while wearing chemical-biological-nuclear protective clothes. Methods Twelve male students with mean age of 25 ± 2 and body mass index (BMI of 23 ± 1.5 were recruited in the experiment. Each student ran on a treadmill with a speed of 2.4 km/hour in the climate chamber at 35°C and 30% relative humidity. physiological strain index score, oral temperature, heart rate, reaction time and number of errors were measured at the end of the two levels and analyzed by the SPSS software. Results Wilcoxon test showed that the differences of physiological strain index score (P = 0.02, oral temperature (P = 0.02, reaction time (P = 0.02, heart Rate (P = 0.02 and errors (P = 0.03 with and without the cooling vest were significant. The mean physiological strain index score without cooling vest was 4.038 ± 0.882 and with the cooling vest was 1.42 ± 0.435. The mean reaction time without and with the cooling vest was 0.769 ± 0.0972 and 0.539 ± 0.977, respectively. Conclusions The results of the study showed that the cooling vest reduces the physiological strain, reaction time and errors rate of workers.

  12. Employer's Manual on Affirmative Action in Employment.

    Science.gov (United States)

    Kentucky State Commission on Human Rights, Frankfort.

    The express purpose of this manual is for its use by business and industry in Kentucky as an aid to eliminate discrimination. Affirmative action is defined here as a comprehensive effort by an employer designed to: employ women and minority persons where they are under-utilized; include minority persons and women in all facets of the company's…

  13. Employing Discourse: Universities and Graduate "Employability"

    Science.gov (United States)

    Boden, Rebecca; Nedeva, Maria

    2010-01-01

    What constitutes graduate employability is discursively framed. In this paper we argue that whilst universities in the UK have long had an involvement in producing useful and productive citizens, the ongoing neoliberalisation of higher education has engendered a discursive shift in definitions of employability. Traditionally, universities regarded…

  14. Investigation of Synthesis and Magnetic Properties of Rod-Shaped CoFe2O4 via Precipitation-Topotactic Reaction Employing α-FeOOH and γ-FeOOH As Templates

    Science.gov (United States)

    Cao, Xiaohui; Dong, Hongfei; Tan, Yuzhuo; Meng, Jinhong

    2018-03-01

    Rod-shaped CoFe2O4 was prepared by chemical precipitation-topotactic reaction method, and in this preparation needle-like γ-FeOOH and α-FeOOH were synthesized to use as template materials. The evolution of phase and morphology in the process of calcination exhibits that α-FeOOH and γ-FeOOH experienced different routes to form the α-Fe2O3 middle phase with different crystallinity and morphology. The synthesis process of CoFe2O4 revealed that the crystallinity, purity and morphology of CoFe2O4 depend on the α-Fe2O3 middle phase. The magnetic measurement showed that the CoFe2O4 prepared from α-FeOOH has higher saturation magnetization and coercivity, and the crystallinity and morphology may play important roles in achieving a better magnetic performance.

  15. "Once the government employs you, it forgets you": Health workers' and managers' perspectives on factors influencing working conditions for provision of maternal health care services in a rural district of Tanzania.

    Science.gov (United States)

    Mkoka, Dickson Ally; Mahiti, Gladys Reuben; Kiwara, Angwara; Mwangu, Mughwira; Goicolea, Isabel; Hurtig, Anna-Karin

    2015-09-14

    In many developing countries, health workforce crisis is one of the predominant challenges affecting the health care systems' function of providing quality services, including maternal care. The challenge is related to how these countries establish conducive working conditions that attract and retain health workers into the health care sector and enable them to perform effectively and efficiently to improve health services particularly in rural settings. This study explored the perspectives of health workers and managers on factors influencing working conditions for providing maternal health care services in rural Tanzania. The researchers took a broad approach to understand the status of the current working conditions through a governance lens and brought into context the role of government and its decentralized organs in handling health workers in order to improve their performance and retention. In-depth interviews were conducted with 22 informants (15 health workers, 5 members of Council Health Management Team and 2 informants from the District Executive Director's office). An interview guide was used with questions pertaining to informants' perspective on provision of maternal health care service, working environment, living conditions, handling of staff's financial claims, avenue for sharing concerns, opportunities for training and career progression. Probing questions on how these issues affect the health workers' role of providing maternal health care were employed. Document reviews and observations of health facilities were conducted to supplement the data. The interviews were analysed using a qualitative content analysis approach. Overall, health workers felt abandoned and lost within an unsupportive system they serve. Difficult working and living environments that affect health workers' role of providing maternal health care services were dominant concerns raised from interviews with both health workers and managers. Existence of a bureaucratic and

  16. Behavioral and EEG reactions in primary school-aged children to emotionally colored verbal stimuli with the condition of their own or forced choice

    Directory of Open Access Journals (Sweden)

    Aiusheeva T. A.

    2017-12-01

    Full Text Available The aim of the study is to compare behavioral and EEG reactions of primary school-aged children during the recognition of syntactic errors in emotionally (positively or negatively colored sentences that appeal to the choice of the child differently. 20 children (mean age 9,0±0,3 years, 12 boys, 8 girls were examined. We found out that the children with a high quality of solving a linguistic task concentrate all their attention on finding an error in the sentences, and children with a low quality of solving a task demonstrate increased emotionality, possibly connected with their unsuccessfulness. The strongest EEG reactions in the ranges of alpha- and theta- rhythms were recorded in children with slow speed and bad quality of the solution of the task. The recognition of sentences with negative emotions took longer than sentences with positive emotions. The increase of emotions (synchronization in theta range during the recognition of negative sentences was provoked by the expectation of failure and “identification” with it. The children found the mistake better in the sentences with their own choice than in the sentences that describes the forced-choice situation. Desynchronization (i.e. decrease in the spectral power and synchronization (i.e. increase in spectral power was detected on the EEG in the alpha-rhythm range. Desynchronization was associated with the recognition of sentences describing the children’s own choice; synchronization was recorded when recognizing sentences describing the forced-choice situation.

  17. Co-formation of hydroperoxides and ultra-fine particles during the reactions of ozone with a complex VOC mixture under simulated indoor conditions

    DEFF Research Database (Denmark)

    Fan, Z.H.; Weschler, Charles J.; Han, IK

    2005-01-01

    In this study we examined the co-formation of hydrogen peroxide and other hydroperoxides (collectively presented as H2O2*) as well as submicron particles, including ultra-fine particles (UFP), resulting from the reactions of ozone (O-3) with a complex mixture of volatile organic compounds (VOCs...... higher than typical indoor levels. When O-3 was added to a 25-m(3) controlled environmental facility (CEF) containing the 23 VOC mixture, both H2O2* and submicron particles were formed. The 2-h average concentration of H2O2* was 1.89 +/- 0.30ppb, and the average total particle number concentration was 46...... to achieve saturated concentrations of the condensable organics. When the 2 terpenes were removed from the O-3/23 VOCs mixture, no H2O2* or particles were formed, indicating that the reactions of O-3 With the two terpenes were the key processes contributing to the formation of H2O2* and submicron particles...

  18. The development and experimental validation of a reduced ternary kinetic mechanism for the auto-ignition at HCCI conditions, proposing a global reaction path for ternary gasoline surrogates

    Energy Technology Data Exchange (ETDEWEB)

    Machrafi, Hatim; Cavadias, Simeon; Amouroux, Jacques [UPMC Universite Paris 06, LGPPTS, Ecole Nationale Superieure de Chimie de Paris, 11, rue de Pierre et Marie Curie, 75005 Paris (France)

    2009-02-15

    To acquire a high amount of information of the behaviour of the Homogeneous Charge Compression Ignition (HCCI) auto-ignition process, a reduced surrogate mechanism has been composed out of reduced n-heptane, iso-octane and toluene mechanisms, containing 62 reactions and 49 species. This mechanism has been validated numerically in a 0D HCCI engine code against more detailed mechanisms (inlet temperature varying from 290 to 500 K, the equivalence ratio from 0.2 to 0.7 and the compression ratio from 8 to 18) and experimentally against experimental shock tube and rapid compression machine data from the literature at pressures between 9 and 55 bar and temperatures between 700 and 1400 K for several fuels: the pure compounds n-heptane, iso-octane and toluene as well as binary and ternary mixtures of these compounds. For this validation, stoichiometric mixtures and mixtures with an equivalence ratio of 0.5 are used. The experimental validation is extended by comparing the surrogate mechanism to experimental data from an HCCI engine. A global reaction pathway is proposed for the auto-ignition of a surrogate gasoline, using the surrogate mechanism, in order to show the interactions that the three compounds can have with one another during the auto-ignition of a ternary mixture. (author)

  19. Degradation of γ-HCH spiked soil using stabilized Pd/Fe0 bimetallic nanoparticles: Pathways, kinetics and effect of reaction conditions

    International Nuclear Information System (INIS)

    Singh, Ritu; Misra, Virendra; Mudiam, Mohana Krishna Reddy; Chauhan, Lalit Kumar Singh; Singh, Rana Pratap

    2012-01-01

    Highlights: ► This study explores the potential of CMC-Pd/nFe 0 to degrade γ-HCH in spiked soil. ► Sorption–desorption characteristics and partitioning of γ-HCH is investigated. ► Three degradation pathways has been proposed and discussed. ► γ-HCH degradation mechanism and kinetics is elucidated. ► Activation energy reveals that γ-HCH degradation is a surface mediated reaction. - Abstract: This study investigates the degradation pathway of gamma-hexachlorocyclohexane (γ-HCH) in spiked soil using carboxymethyl cellulose stabilized Pd/Fe 0 bimetallic nanoparticles (CMC-Pd/nFe 0 ). GC–MS analysis of γ-HCH degradation products showed the formation of pentachlorocyclohexene, tri- and di-chlorobenzene as intermediate products while benzene was formed as the most stable end product. On the basis of identified intermediates and final products, degradation pathway of γ-HCH has been proposed. Batch studies showed complete γ-HCH degradation at a loading of 0.20 g/L CMC-Pd/nFe 0 within 6 h of incubation. The surface area normalized rate constant (k SA ) was found to be 7.6 × 10 −2 L min −1 m −2 . CMC-Pd/nFe 0 displayed ∼7-fold greater efficiency for γ-HCH degradation in comparison to Fe 0 nanoparticles (nFe 0 ), synthesized without CMC and Pd. Further studies showed that increase in CMC-Pd/nFe 0 loading and reaction temperature facilitates γ-HCH degradation, whereas a declining trend in degradation was noticed with the increase in pH, initial γ-HCH concentration and in the presence of cations. The data on activation energy (33.7 kJ/mol) suggests that γ-HCH degradation is a surface mediated reaction. The significance of the study with respect to remediation of γ-HCH contaminated soil using CMC-Pd/nFe 0 has been discussed.

  20. Elucidation of Diels-Alder Reaction Network of 2,5-Dimethylfuran and Ethylene on HY Zeolite Catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Do, Phuong T. M. [Univ. of Delaware, Newark, DE (United States); McAtee, Jesse R. [Univ. of Delaware, Newark, DE (United States); Watson, Donald A. [Univ. of Delaware, Newark, DE (United States); Lobo, Raul F. [Univ. of Delaware, Newark, DE (United States)

    2012-12-12

    The reaction of 2,5-dimethylfuran and ethylene to produce p-xylene represents a potentially important route for the conversion of biomass to high-value organic chemicals. Current preparation methods suffer from low selectivity and produce a number of byproducts. Using modern separation and analytical techniques, the structures of many of the byproducts produced in this reaction when HY zeolite is employed as a catalyst have been identified. From these data, a detailed reaction network is proposed, demonstrating that hydrolysis and electrophilic alkylation reactions compete with the desired Diels–Alder/dehydration sequence. This information will allow the rational identification of more selective catalysts and more selective reaction conditions.

  1. An alkaline one-pot reaction to synthesize luminescent Eu-BTC MOF nanorods, highly pure and water-insoluble, under room conditions

    Energy Technology Data Exchange (ETDEWEB)

    Medina-Velazquez, D. Y., E-mail: dyolotzin@correo.azc.uam.mx; Alejandre-Zuniga, B. Y.; Loera-Serna, S.; Ortiz, E. M. [Universidad Autónoma Metropolitana-Azcapotzalco, División de Ciencias Básicas e Ingeniería (Mexico); Morales-Ramirez, A. de J. [CIITEC IPN, Instituto Politécnico Nacional (Mexico); Garfias-Garcia, E. [Universidad Autónoma Metropolitana-Azcapotzalco, División de Ciencias Básicas e Ingeniería (Mexico); Garcia-Murillo, A. [CIITEC IPN, Instituto Politécnico Nacional (Mexico); Falcony, C. [Centro de Investigación y Estudios Avanzados, Departamento de Física (Mexico)

    2016-12-15

    The increasing demand for optoelectronic devices requires the development of luminescent materials with high luminescence efficiency and low energy demands, and the metalorganic frameworks (MOFs) with lanthanides ions offer great potential in this area. The metalorganic materials provide properties of flexibility, low density, low-cost methods of synthesis, and insolubility in water, which gives them an advantage over traditional phosphors. In this study, a benzenetricarboxylate ligand (BTC) with a Eu{sup 3+} MOF was synthesized, and its structural and luminescent properties were measured. The metalorganic compound was generated in a one-pot reaction from europium nitrate and trimesic acid precursors. Through characterization by X-ray diffraction powder, infrared spectroscopy, SEM structural characterization, and luminescent spectroscopy, the formation of Europium benzenetricarboxylate (Eu-BTC) MOF nanorods was tested and the calculated value was in the range of 30–60 nm. A red luminescent emission with high intensity was observed for all the procedures.

  2. Characterisation of manganese peroxidase and laccase producing bacteria capable for degradation of sucrose glutamic acid-Maillard reaction products at different nutritional and environmental conditions.

    Science.gov (United States)

    Kumar, Vineet; Chandra, Ram

    2018-02-02

    Maillard reactions products (MRPs) are a major colorant of distillery effluent. It is major source of environmental pollution due to its complex structure and recalcitrant nature. This study has revealed that sucrose glutamic acid-Maillard reaction products (SGA-MRPs) showed many absorption peaks between 200 and 450 nm. The absorption maximum peak was noted at 250 nm in spectrophotometric detection. This indicated the formation of variable molecular weight Maillard products during the SGA-MRPs formation at high temperature. The identified aerobic bacterial consortium consisting Klebsiella pneumoniae (KU726953), Salmonella enterica (KU726954), Enterobacter aerogenes (KU726955), Enterobacter cloaceae (KU726957) showed optimum production of MnP and laccase at 120 and 144 h of growth, respectively. The potential bacterial consortium showed decolourisation of Maillard product up to 70% in presence of glucose (1%), peptone (0.1%) at optimum pH (8.1), temperature (37 °C) and shaking speed (180 rpm) within 192 h of incubation. The reduction of colour of Maillard product correlated with shifting of absorption peaks in UV-Vis spectrophotometry analysis. Further, the changing of functional group in FT-IR data showed appearance of new peaks and GC-MS analysis of degraded sample revealed the depolymerisation of complex MRPs. The toxicity evaluation using seed of Phaseolus mungo L. showed reduction of toxicity of MRPs after bacterial treatment. Hence, this study concluded that developed bacterial consortium have capability for decolourisation of MRPs due to high content of MnP and laccase.

  3. Nuclear reactions

    International Nuclear Information System (INIS)

    Lane, A.M.

    1980-01-01

    In reviewing work at Harwell over the past 25 years on nuclear reactions it is stated that a balance has to be struck in both experiment and theory between work on cross-sections of direct practical relevance to reactors and on those relevant to an overall understanding of reaction processes. The compound nucleus and direct process reactions are described. Having listed the contributions from AERE, Harwell to developments in nuclear reaction research in the period, work on the optical model, neutron capture theory, reactions at doorway states with fine structure, and sum-rules for spectroscopic factors are considered in more detail. (UK)

  4. The Employer Perspective on Sustainable Employability in the Construction Industry

    NARCIS (Netherlands)

    Tonnon, Susanne C; van der Veen, Rozan; Westerman, Marjan J; Robroek, Suzan J W; van der Ploeg, Hidde P; Van Der Beek, Allard J.; Proper, Karin I.

    OBJECTIVE: To determine the measures employers in the construction industry take to promote sustainable employability, the barriers and facilitators that influence implementation and employer needs. METHODS: Questionnaire among 499 employers and interviews with 17 employers. RESULTS: Employers

  5. An easy access to 2-Amino-5,6-dihydro-3H-pyrimidin-4-one building blocks: the reaction under conventional and microwave conditions.

    Science.gov (United States)

    Ostras, Konstantin S; Gorobets, Nikolay Yu; Desenko, Sergey M; Musatov, Vladimir I

    2006-08-01

    A new one-stage fast multicomponent synthesis of title compounds leads to products in 21-55% isolated yields under both conventional and microwave conditions. The primary amino group in the building blocks can be easily acylated by various usual electophilic agents that can be utilized in the synthesis of diverse heterocylic compounds libraries.

  6. Storage conditions of blood samples and primer selection affect the yield of cDNA polymerase chain reaction products of hepatitis C virus

    NARCIS (Netherlands)

    Cuypers, H. T.; Bresters, D.; Winkel, I. N.; Reesink, H. W.; Weiner, A. J.; Houghton, M.; van der Poel, C. L.; Lelie, P. N.

    1992-01-01

    We have noticed that suboptimal specimen processing and storage conditions may cause false-negative results in the detection of hepatitis C virus (HCV) RNA in plasma or serum. To establish the influence of specimen handling in a serological laboratory on the rate of detection of HCV RNA by the cDNA

  7. Revisiting the Reaction Between Diaminomaleonitrile and Aromatic Aldehydes: a Green Chemistry Approach

    Directory of Open Access Journals (Sweden)

    Francisco León

    2006-11-01

    Full Text Available The reaction between diaminomaleonitrile (DAMN and aldehydes and the resulting monoimines are well known. Since the standard reaction conditions involve the use of toxic solvents (typically methanol, we have sought to apply green chemistry principles to this reaction by either using water as the solvent without any catalysts or employing “solvent-free” conditions. The monoimines derived from DAMN are of interest as precursors for obtaining different heterocyclic systems and linear polymers. The methodologies used have significant advantages with regards to cost and environmental considerations.

  8. Perspectives of employability skills

    OpenAIRE

    ANNE LOUISE NEWTON

    2017-01-01

    The study investigated the different perspectives held by young people, employers and policy makers around Employability Skills and it examined how young people learnt these skills. This study draws young peoples’ perspectives into the research around Employability Skills and highlights the way in which social and cultural capital mediate their development. The research points to a model to re-vision employability skills which recognises the many ways in which they are learnt, over time a...

  9. Characterization of recombinant nitrile-specifier proteins (NSPs) of Arabidopsis thaliana: dependency on Fe(II) ions and the effect of glucosinolate substrate and reaction conditions.

    Science.gov (United States)

    Kong, Xiang Yi; Kissen, Ralph; Bones, Atle M

    2012-12-01

    Glucosinolates are plant secondary metabolites that are part of a plant defence system against pathogens and pests, the myrosinase-glucosinolate system, in which glucosinolates get activated by enzymic degradation through thioglucoside glucohydrolases called myrosinases. Epithiospecifier protein (ESP) and nitrile-specifier proteins (NSPs) divert myrosinase-catalyzed hydrolysis of a given glucosinolate from the formation of isothiocyanate to that of epithionitrile and/or nitrile. As the biological activity of glucosinolate hydrolysis products varies considerably, a detailed characterization of these specifier proteins is of utmost importance to understand their biological role. Therefore, the Arabidopsis thaliana AtNSP1, AtNSP2 and AtNSP5 and a supposed ancestor protein AtNSP-like1 were expressed in Escherichia coli and the activity of the purified recombinant proteins was tested in vitro on three highly different glucosinolates and compared to that of purified AtESP. As previously reported, only AtESP showed epithiospecifier activity on 2-propenylglucosinolate. We further confirmed that purified AtNSP1, AtNSP2 and AtNSP5, but not the ancestor AtNSP-like1 protein, show nitrile-specifier activity on 2-propenylglucosinolate and benzylglucosinolate. We now show for the first time that in vitro AtNSP1, AtNSP2 and AtNSP5 are able to generate nitrile from indol-3-ylmethylglucosinolate. We also tested the effect of different Fe(II) ion concentrations on the nitrile-specifier activity of purified AtNSP1, AtNSP2 and AtNSP5 on 2-propenylglucosinolate and benzylglucosinolate. AtNSP-related nitrile production was highly dependent on the presence of Fe(II) ions in the reaction assay. In the absence of added Fe(II) ions nitriles were only detected when benzylglucosinolate was incubated with AtNSP1. While AtNSP1 also exhibited overall higher nitrile-specifier activity than AtNSP2 and AtNSP5 at a given Fe(II) ion concentration, the pattern of nitrile formation in relation to Fe

  10. Youth employment in Egypt

    OpenAIRE

    Eekelen, Willem van; De Luca, Loretta; Ismail, Magwa

    2001-01-01

    Examines economic and social factors affecting youth employment in Egypt and describes three national programmes for the promotion of youth employment based on human resources development, direct job creation and support in self-employment and enterprise creation. Describes one public-private project in each case.

  11. Employment in Agribusiness.

    Science.gov (United States)

    Hilgenberg, Gene; Huston, Jane

    This curriculum guide is intended to assist persons teaching a course in employment in agribusiness. Addressed in the individual units of instruction are the following topics: employment information (training plans/agreements and wages, taxes, and fringe benefits); human relations (employer/employee/customer relations and communication skills);…

  12. Social innovation in employment

    NARCIS (Netherlands)

    Oeij, P.R.A.; Torre, W. van der; Santoclides, M.E

    2017-01-01

    This policy brief on Social Innovation of Employment informs on an inventory of challenges and policy recommendations based on the Case Study Report of Employment and on the Second Policy Foresight Workshop of Employment. A ‘paradigm shift’ is needed in the mind-set of policymakers. ‘Traditional’

  13. Rate Constants for the Reactions of OH with CO, NO and NO2, and of HO2 with NO2 in the Presence of Water Vapour at Lower-Tropospheric Conditions

    Science.gov (United States)

    Rolletter, Michael; Fuchs, Hendrik; Novelli, Anna; Ehlers, Christian; Hofzumahaus, Andreas

    2016-04-01

    Recent studies have shown that the chemistry of gaseous nitrous acid (HONO) in the lower troposphere is not fully understood. Aside from heterogenous reactions, the daytime HONO formation in the gas-phase is not well understood (Li et al., Science, 2014). For a better understanding of HONO in the gas-phase, we have reinvestigated the reaction rate constants of important tropospheric reactions of the HOx radical family (OH and HO2) with nitrogen oxides at realistic conditions of the lower troposphere (at ambient temperature/pressure and in humid air). In this study we apply a direct pump and probe technique with high accuracy, using small radical concentrations to avoid secondary chemistry. Pulsed laser photolysis/laser-induced fluorescence (LP/LIF) was used to investigate the reaction rate constants of OH with CO, NO, NO2, and HO2 with NO2 in synthetic air at different water vapor concentrations (up to 5 x 1017 molecules cm-3). Photolysis of ozone in the presence of gaseous water was the source of OH. The reactions took place in a flow-tube at room temperature and atmospheric pressure. The chemical decay of the radicals was monitored by laser-induced fluorescence detection in a low-pressure cell, which sampled air continuously from the end of the flow-tube. Knowing the reactant concentrations subsequently allowed to calculate the bimolecular reaction rate constants at 1 atm from the pseudo-first-order decays. In order to observe HO2 reactions, OH was converted into HO2 with an excess of CO in the flow-tube. The newly measured rate constants for OH with CO, NO and NO2 agree very well with current recommendations by NASA/JPL and IUPAC and have an improved accuracy (uncertainty < 5%). These rate coefficients are independent of the presence of water vapour. The measured rate constant of HO2 with NO2 was found to depend significantly on the water-vapour concentration (probably due to formation of HO2*H2O complexes) and to exceed current recommendations by NASA/JPL and

  14. Co-Production of Ethanol and 1,2-Propanediol via Glycerol Hydrogenolysis Using Ni/Ce–Mg Catalysts: Effects of Catalyst Preparation and Reaction Conditions

    Directory of Open Access Journals (Sweden)

    Russel N. Menchavez

    2017-09-01

    Full Text Available Crude glycerol from biodiesel production is a biobased material capable of co-producing biofuels and chemicals. This study aimed to develop a line of Ni catalysts supported on cerium–magnesium (Ce–Mg to improve the process efficiency of glycerol hydrogenolysis for ethanol and 1,2-propanediol (1,2-PDO. Results showed that catalytic activity was greatly improved by changing the preparation method from impregnation to deposition precipitation (DP, and by adjusting calcination temperatures. Prepared via DP, the catalysts of 25 wt % Ni supported on Ce–Mg (9:1 mol/mol greatly improved the effectiveness in glycerol conversion while maintaining the selectivities to ethanol and 1,2-PDO. Calcination at 350 °C provided the catalysts better selectivities of 15.61% to ethanol and 67.93% to 1,2-PDO. Increases in reaction temperature and time improved the conversion of glycerol and the selectivity to ethanol, but reduced the selectivity to 1,2-PDO. A lower initial water content led to a higher conversion of glycerol, but lower selectivities to ethanol and 1,2-PDO. Higher hydrogen application affected the glycerol conversion rate positively, but the selectivities to ethanol and 1,2-PDO negatively. A comparison to the commercial Raney® Ni catalyst showed that the Ni/Ce–Mg catalyst developed in this study showed a better potential for the selective co-production of ethanol and 1,2-PDO from glycerol hydrogenolysis.

  15. Asymmetric H-D exchange reactions of fluorinated aromatic ketones

    KAUST Repository

    Zhao, Yujun

    2012-01-01

    Chiral bicyclic guanidine catalyzes the asymmetric H-D exchange reactions. Up to 30% ee was achieved. DFT calculations were employed to elucidate and explain the origin of the reaction\\'s stereoselectivity. © 2012 The Royal Society of Chemistry.

  16. Employers Roundtable: Employer Supported Child Care.

    Science.gov (United States)

    Delaware Valley Child Care Council, Philadelphia, PA.

    This booklet outlines a number of options available to employers to enable them to better cope with child care issues that they and their employees face. Major options include: (1) flexible work policies, such as flexible scheduling, alternate work places, shorter work weeks, and the consolidating of sick leave, holidays, and vacation time into…

  17. Sn-PILC: A novel Efficient and Recyclable Catalyst for One-pot Three Component Povarov’s Inverse-electron-demand Hetero Diels-Alder Reaction for a Facile Synthesis of Tetrahydropyranoquinoline Derivatives under Neat Conditions

    Directory of Open Access Journals (Sweden)

    Megha Rai

    2016-07-01

    Full Text Available The Povarov’s inverse-electron-demand hetero Diels–Alder one-pot three components reaction of aromatic aldehyde, aromatic amine with DHF has been developed using Sn-PILC as a catalyst under a neat condition which may helpful to society to get pharmacologically more active compounds. In the present study a novel series of tetrahydroquinoline 4(a-f were synthesized and characterized by IR, 1HNMR, 13CNMR, Mass spectral analysis and elemental analysis. The synthetic details and characterization results are discussed. DOI: http://dx.doi.org/10.17807/orbital.v8i3.801

  18. Influence of reaction conditions on formation of ionic liquid-based nanostructured Bi2O3 as an efficient visible-light-driven photocatalyst

    Science.gov (United States)

    Bagheri, Mozhgan; Heydari, Mojgan; Vaezi, Mohammad Reza

    2018-01-01

    In this study, nanostructured bismuth oxide was synthesized based on the chemical reaction of bismuth nitrate and NaOH in the ionic liquid 1-butyl-3-methylimidazolium chloride ([C4mim]Cl) under ultrasonic irradiation. The effect of sodium hydroxide with a different molar ratio of NaOH to bismuth in the range of 3-10 was investigated. The results of fourier-transform infrared spectroscopy (FT-IR) and X-ray powder diffraction (XRD) showed that NaOH has a critical role in the formation of pure α-Bi2O3. So, at high concentrations of NaOH (NaOH:Bi ≥ 7.5), the chloride anion from the ionic liquid cannot be entered into the crystalline structure of bismuth oxide, which resulted in the formation of pure bismuth oxide, while at lower concentrations of NaOH (NaOH:Bi ≤ 5), Bi3O4Cl was formed with a layered structure. The XRD results revealed that the synthesized α-Bi2O3 has a monoclinic structure and scanning electron microscopy (SEM) images showed that the sample consists of needle like particles with an average thickness of 50 nm. The ionic liquid has an important role in the prevention of an agglomeration of particles in the Bi2O3 sample. The photocatalytic activity of the synthesized Bi2O3 was investigated to study the degradation of malachite green dye as a model pollutant under visible light. The effects of various parameters such as the pH, concentration of the dye, and the catalyst on the degradation of malachite green were also investigated.

  19. Synthesis of Zr-Si-O-N phases by carbonitriding reaction. Characterization of crystalline phases using the Rietveld method

    Directory of Open Access Journals (Sweden)

    Mazzoni A.D.

    2001-01-01

    Full Text Available Zirconium compounds are of great interest for ceramic application due to their excellent thermal and mechanical properties. Zirconium phases of the system Zr-O-C-N were obtained using carbonitriding reactions of zircon mineral (ZrO2.SiO2, under different reaction conditions. The reaction products were studied by X-ray diffraction (XRD using the Rietveld method. Silicon was employed as internal standard. Zirconium compounds formed were m-ZrO2 (monoclinic, beta"-zirconium oxynitride and a cubic Zr(C,N,O phase whose lattice parameter a o depends on the composition. The crystallite sizes of the three zirconium phases were determined also by XRD. The minority phases present are the ones of the Si-O-N-C system. The reaction conditions employed allows to obtain reaction products with low or without silicon content.

  20. Global exponential stability of reaction-diffusion recurrent neural networks with time-varying delays

    International Nuclear Information System (INIS)

    Liang Jinling; Cao Jinde

    2003-01-01

    Employing general Halanay inequality, we analyze the global exponential stability of a class of reaction-diffusion recurrent neural networks with time-varying delays. Several new sufficient conditions are obtained to ensure existence, uniqueness and global exponential stability of the equilibrium point of delayed reaction-diffusion recurrent neural networks. The results extend and improve the earlier publications. In addition, an example is given to show the effectiveness of the obtained result

  1. The redox-Mannich reaction.

    Science.gov (United States)

    Chen, Weijie; Seidel, Daniel

    2014-06-06

    A complement to the classic three-component Mannich reaction, the redox-Mannich reaction, utilizes the same starting materials but incorporates an isomerization step that enables the facile preparation of ring-substituted β-amino ketones. Reactions occur under relatively mild conditions and are facilitated by benzoic acid.

  2. Allergic Reactions

    Science.gov (United States)

    American Academy of Allergy Asthma & Immunology Menu Search Main navigation Skip to content Conditions & Treatments Allergies Asthma Primary Immunodeficiency Disease Related Conditions Drug Guide Conditions Dictionary Just ...

  3. In situ formation of the amino sugars 1-amino-1-deoxy-fructose and 2-amino-2-deoxy-glucose under Maillard reaction conditions in the absence of ammonia.

    Science.gov (United States)

    Nashalian, Ossanna; Yaylayan, Varoujan A

    2016-04-15

    Replacing amino acids with their binary metal complexes during the Maillard reaction can initiate various processes, including the oxidative degradation of their glucose conjugates, generating 1-amino-1-deoxy-fructose and its derivatives. These reactive amino sugars are not easily accessible under Maillard reaction conditions and are only formed in the presence of ammonia. To explore the generality of this observation and to study in particular the ability of fructose to generate glucosamine, the amino acid-metal complexes were heated in aqueous solutions with three aldohexoses and two ketohexoses at 110°C for 2 h and the dry residues were analysed by ESI/qTOF/MS/MS. All the sugars generated relatively intense ions at [M+H](+) 180 (C6H14NO5); those ions originating from ketohexoses exhibited MS/MS fragmentations identical to glucosamine and those originating form aldohexoses showed ions identical to fructosamine. Furthermore, the amino sugars were found to form fructosazine, react with other sugars and undergo dehydration reactions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Encapsulation of Hemin in Metal-Organic Frameworks for Catalyzing the Chemiluminescence Reaction of the H2O2-Luminol System and Detecting Glucose in the Neutral Condition.

    Science.gov (United States)

    Luo, Fenqiang; Lin, Yaolin; Zheng, Liyan; Lin, Xiaomei; Chi, Yuwu

    2015-06-03

    Novel metal-organic frameworks (MOFs) based solid catalysts have been synthesized by encapsulating Hemin into the HKUST-1 MOF materials. These have been first applied in the chemiluminescence field with outstanding performance. The functionalized MOFs not only maintain an excellent catalytic activity inheriting from Hemin but also can be cyclically utilized as solid mimic peroxidases in the neutral condition. The synthesized Hemin@HKUST-1 composites have been used to develop practical sensors for H2O2 and glucose with wide response ranges and low detection limits. It was envisioned that catalyst-functionalized MOFs for chemiluminescence sensing would have promising applications in green, selective, and sensitive detection of target analytes in the future.

  5. Investigating Ionic Effects Applied to Water Based Organocatalysed Aldol Reactions

    Directory of Open Access Journals (Sweden)

    Joshua P. Delaney

    2011-12-01

    Full Text Available Saturated aqueous solutions of various common salts were examined for their effect on aqueous aldol reactions catalysted by a highly active C2-symmetric diprolinamide organocatalyst developed in our laboratory. With respect to the aldol reaction between cyclohexanone and 4-nitrobenzaldehyde, deionised water was always a superior medium to salt solutions though some correlation to increasing anion size and depression in enantiomeric excess could be observed. Additionally, the complete inhibition of catalyst activity observed when employing tap water could be alleviated by the inclusion of ethylenediaminetetraacetate (EDTA into the aqueous media prior to reaction initiation. Extension of these reaction conditions demonstrated that these ionic effects vary on a case-to-case basis depending on the ketone/aldehyde combination.

  6. Information Literacy and Employability

    OpenAIRE

    O'Keeffe, Colin

    2016-01-01

    Information Literacy (IL) and its relationship to third level graduates’ employability has gained more attention in recent years. This article examines how IL has evolved from skills initially associated with academic libraries into a key workplace skill set of the knowledge economy. It outlines the challenges interviewees encounter when selling IL to employers, how IL can be utilised when preparing for upcoming interviews and suggests a distinction between workplace IL and employability IL. ...

  7. Optimization of transesterification reaction conditions for the production of biodiesel from oil blend of castor bean and soybean; Otimizacao das condicoes reacionais de transesterizacao para producao de biodiesel a partir de mistura de oleos de mamona e soja

    Energy Technology Data Exchange (ETDEWEB)

    Lobato, Ana Katerine de Carvalho Lima; Lima, Milena Gouveia Oliveira de; Pontes, Luiz Antonio M.; Teixeira, Leonardo S.G. [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil); Almeida, Daniel Freire; Costa, Tales Santana Martins; Menezes; Mateus Della Cella; Santos, Iran Talis Viana; Almeida, Selmo Q. [Universidade Salvador (UNIFACS), BA (Brazil)

    2012-07-01

    Biodiesel is an alternative fuel to diesel oil, and industrially obtained by the transesterification of triglycerides of fatty acids from vegetable oils and/or animal fats. Currently, the main raw material used to produce biodiesel in Brazil is soybean oil. The inclusion of other raw materials from different cultures in this sector is important and aims to reduce dependence on a single oilseed, assign specific characteristics to the product and encourage the development of family farming. The use of blends of soybean oil and castor for biodiesel may prove an important strategy to minimize the negative effects and maximize the positives of each oilseed. In this work, we carried out an experimental study using full factorial design 2{sup 4}, to increase the conversion of esters, by conventional transesterification, using as feedstock a blend of oils containing 20% castor and 80% soybean. The aim of this study was to evaluate the influence of mixing ratio of oil: methanol, KOH concentration, temperature and reaction time in biodiesel production. It was found that the variation of these parameters affected the conversion of esters and quality of biodiesel produced. Conversions above 95% were obtained, and the best conversion was 99.05% at 25 deg C in a reaction time of 20 minutes using 2% KOH as a catalyst and a molar ratio methanol/oil 12:1. In order to reduce the costs of the process with respect to amount of methanol used without affecting the conversion of esters, we identified a second set of process conditions, which used the same conditions of temperature, reaction time and catalyst concentration and a different molar ratio methanol/oil (6:1) which gave a conversion of esters of 98.59%. (author)

  8. General Outside Employment

    Data.gov (United States)

    Montgomery County of Maryland — This dataset contains all outside employment requests held by employees of Montgomery County (excluding uniformed police officer) approved by the Ethics Commission...

  9. Secretary Marshall's Employment Strategies

    Science.gov (United States)

    Stevenson, Gloria

    1977-01-01

    A review of proposed employment strategies and priorities of Ray Marshall, Secretary of Labor, with regard to training programs, governmental subsidy programs, apprenticeships, private sector jobs, etc. (WL)

  10. Institutionalized Employer Collective Action

    DEFF Research Database (Denmark)

    Ibsen, Christian Lyhne; Navrbjerg, Steen Erik

    2016-01-01

    Recent studies show that employer associations continue to exist in new ways despite internationalisation of the economy, liberalisation of markets and the decline of trade unions. This paradox raises two questions regarding EOs in today’s labour markets: Which employers join employer associations...... and what kind of services do EOs offer employers? This article explores these questions using two comprehensive surveys on EOs in Denmark – a prominent case of coordinated market economies. The main finding of the analyses is that collective activities vis-à-vis trade unions and government are still...

  11. Reaction of uranyl nitrate with carboxylic di-acids under hydrothermal conditions. Crystal structure of complexes with L(+)-tartaric and oxalic acids

    International Nuclear Information System (INIS)

    Thuery, P.

    2007-01-01

    L(+)-tartaric acid reacts with uranyl nitrate in the presence of KOH, under mild hydrothermal conditions, to give the complex [UO 2 (C 4 H 4 O 6 )(H 2 O)] (1), the first uranyl tartrate to be crystallographically characterized. Each tartrate ligand bridges three uranyl ions, one of them in chelating fashion through proximal carboxylate and hydroxyl groups. The resulting assemblage is two-dimensional, with the uranyl pentagonal bipyramidal coordination polyhedra separated from one another. Prolonged heating of an uranyl tartrate solution resulted in oxidative cleavage of the acid and formation of the oxalate complex [(UO 2 ) 2 (C 2 O 4 ) 2 (OH)Na(H 2 O) 2 ] (2). The bis-bidentate oxalate and bridging hydroxide groups ensure the formation of sheets with corner-sharing uranyl pentagonal bipyramidal coordination polyhedra, in which six-membered metallacycles encompass the sodium ions. These sheets are assembled into a three-dimensional framework through further oxo-bonding of the sodium ions. (authors)

  12. Gene expression reaction norms unravel the molecular and cellular processes underpinning the plastic phenotypes of Alternanthera philoxeroides in contrasting hydrological conditions

    Directory of Open Access Journals (Sweden)

    Lexuan eGao

    2015-11-01

    Full Text Available Alternanthera philoxeroides is an amphibious invasive weed that can colonize both aquatic and terrestrial habitats. Individuals growing in different habitats exhibit extensive phenotypic variation but little genetic differentiation. Little is known about the molecular basis underlying environment-induced phenotypic changes. Variation in transcript abundance in A. philoxeroides was characterized throughout the time-courses of pond and upland treatments using RNA-Sequencing. 7,805 genes demonstrated variable expression in response to different treatments,forming 11 transcriptionally coordinated gene groups. Functional enrichment analysis of plastically expressed genes revealed pathway changes in hormone-mediated signaling, osmotic adjustment, cell wall remodeling and programmed cell death, providing a mechanistic understanding of the biological processes underlying the phenotypic changes in A. philoxeroides. Both transcriptional modulation of environmentally sensitive loci and environmentally dependent control of regulatory loci influenced the plastic responses to the environment. Phenotypic responses and gene expression patterns to contrasting hydrological conditions were compared between A. philoxeroides and its alien congener A. pungens. The terricolous A. pungens displayed limited phenotypic plasticity to different treatments. It was postulated based on gene expression comparison that the interspecific variation in plasticity between A. philoxeroides and A. pungens was not due to environmentally-mediated changes in hormone levels but to variations in the type and relative abundance of different signal transducers and receptors expressed in the target tissue.

  13. Shape and catalytic mechanism of RuO{sub 2} particles at CO oxidation reaction conditions. First-principles based multi-scale modeling

    Energy Technology Data Exchange (ETDEWEB)

    Reuter, Karsten [TU Muenchen (Germany). Lehrstuhl fuer Theoretische Chemie

    2016-11-01

    For model catalyst studies on low-index single-crystal surfaces close agreement between detailed measurements and quantitative microkinetic modeling can increasingly be achieved. However, for 'real' catalyst particles, such structure-morphology-activity relationships are only scarcely established. This is prototypically reflected by the situation for RuO{sub 2}, as a most active catalyst for CO oxidation. Here, existing first-principles kinetic modeling is restricted to just one facet, namely the RuO{sub 2}(110) surface, which is not able to fully account for activity data obtained from polycrystalline RuO{sub 2} powder catalysts. The overarching objective of this project was correspondingly to close this gap and demonstrate that similarly close agreement as for individual single-crystal model catalysts can also be achieved for catalyst particles. Specifically, we addressed experiments where an intact RuO{sub 2} bulk structure is conserved, and establish the atomic-scale structure and reactivity of other RuO{sub 2} low-index facets under the gas-phase conditions characteristic for catalytic CO oxidation.

  14. An efficient forward-reverse expectation-maximization algorithm for statistical inference in stochastic reaction networks

    KAUST Repository

    Vilanova, Pedro

    2016-01-01

    reaction networks (SRNs). We apply this stochastic representation to the computation of efficient approximations of expected values of functionals of SRN bridges, i.e., SRNs conditional on their values in the extremes of given time-intervals. We then employ

  15. Diamond Synthesis Employing Nanoparticle Seeds

    Science.gov (United States)

    Uppireddi, Kishore (Inventor); Morell, Gerardo (Inventor); Weiner, Brad R. (Inventor)

    2014-01-01

    Iron nanoparticles were employed to induce the synthesis of diamond on molybdenum, silicon, and quartz substrates. Diamond films were grown using conventional conditions for diamond synthesis by hot filament chemical vapor deposition, except that dispersed iron oxide nanoparticles replaced the seeding. This approach to diamond induction can be combined with dip pen nanolithography for the selective deposition of diamond and diamond patterning while avoiding surface damage associated to diamond-seeding methods.

  16. Classical kinematic model for direct reactions of oriented reagents

    International Nuclear Information System (INIS)

    Schechter, I.; Prisant, M.G.; Levine, R.D.

    1987-01-01

    A simple kinematic model based on the concept of an orientation-dependent critical configuration for reaction is introduced and applied. The model serves two complementary purposes. In the predictive mode the model provides an easily implemented procedure for computing the reactivity of oriented reagents (including those actually amenable to measure) from a given potential energy surface. The predictions of the model are compared against classical trajectory results for the H + D 2 reaction. By use of realistic potential energy surfaces the model is applied to the Li + HF and O + HCl reactions where the HX molecules are pumped by a polarized laser. A given classical trajectory is deemed reactive or not according to whether it can surmount the barrier at that particular orientation. The essential difference with the model of Levine and Bernstein is that the averaging over initial conditions is performed by using a Monte Carlo integration. One can therefore use the correct orientation-dependent shape (and not only height) of the barrier to reaction and, furthermore, use oriented or aligned reagents. Since the only numerical step is a Monte Carlo sampling of initial conditions, very many trajectories can be run. This suffices to determine the reaction cross section for different initial conditions. To probe the products, they have employed the kinematic approach of Elsum and Gordon. The result is a model where, under varying initial conditions, examining final-state distributions or screening different potential energy surfaces can be efficiently carried out

  17. Report on a survey in fiscal 1999. Survey on industrial utilization of microorganism reaction mechanisms under anaerobic condition; 1999 nendo kenki jokenka ni okeru biseibutsu hanno kiko no kogyoteki riyo ni kansuru chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Industrial utilization of reaction mechanisms of microorganisms under anaerobic condition permits structuring energy saving type production processes. The present survey has investigated features of new microorganisms under anaerobic condition and the status of researches thereon inside and outside the country, and discussed their future applications. Chapter 1 compares anaerobic microorganisms and functions of microorganism under anaerobic condition with those aerobic to describe their general features, and describes the purpose of this survey and the summary of the investigations. Chapter 2 surveys the current status of technologies to utilize microorganisms under anaerobic condition. Chapter 3 outlines metabolic characteristics of the anaerobic microorganisms, and extracts functions effective for material production by different anaerobic microorganisms to describe their applicability. Chapter 4 evaluates the system classification for the anaerobic microorganisms utilizing the basic arrangement of 16S rRNA genes, and extracts technical problems therein. Chapter 5 proposes structuring a total methane fermentation system including a raw material collecting process, and enhancing alcohol productivity of Zymomonas bacteria. (NEDO)

  18. Quasielastic reactions

    International Nuclear Information System (INIS)

    Henning, W.

    1979-01-01

    Quasielastic reaction studies, because of their capability to microscopically probe nuclear structure, are still of considerable interest in heavy-ion reactions. The recent progress in understanding various aspects of the reaction mechanism make this aim appear closer. The relation between microscopic and macroscopic behavior, as suggested, for example, by the single proton transfer data to individual final states or averaged excitation energy intervals, needs to be explored. It seems particularly useful to extend measurements to higher incident energies, to explore and understand nuclear structure aspects up to the limit of the energy range where they are important

  19. Maine's Employability Skills Program

    Science.gov (United States)

    McMahon, John M.; Wolffe, Karen E.; Wolfe, Judy; Brooker, Carrie

    2013-01-01

    This Practice Report describes the development and implementation of the "Maine Employability Skills Program," a model employment program developed by the Maine Division for the Blind and Visually Impaired (DBVI). The program was designed to support the efforts of the chronically unemployed or underemployed. These consumers were either…

  20. Maternal Employment: 1979.

    Science.gov (United States)

    Hoffman, Lois Wladis

    1979-01-01

    Maternal employment is a part of modern family life, a response to changes such as smaller families and more efficient household management. Not only does maternal employment meet parents' needs, but it is a pattern better suited for socializing the child for the adult role s/he will occupy. (Author/GC)

  1. Dimensions of Adolescent Employment.

    Science.gov (United States)

    Mael, Fred A.; Morath, Ray A.; McLellan, Jeffrey A.

    1997-01-01

    Examines positive and negative correlates of adolescent work as a function of work dimensions. Results indicate that concurrent costs and benefits of adolescent employment may depend on dimensions of work as well as adolescent characteristics. Adolescent employment was generally related to subsequent work motivation and nonacademic performance.…

  2. Does Supported Employment Work?

    Science.gov (United States)

    Morgan McInnes, Melayne; Ozturk, Orgul Demet; McDermott, Suzanne; Mann, Joshua R.

    2010-01-01

    Providing employment-related services, including supported employment through job coaches, has been a priority in federal policy since the enactment of the Developmental Disabilities Assistance and Bill of Rights Act in 1984. We take advantage of a unique panel data set of all clients served by the South Carolina Department of Disabilities and…

  3. cycloaddition reactions

    Indian Academy of Sciences (India)

    Unknown

    Molecular Modeling Group, Organic Chemical Sciences, Indian Institute of Chemical Technology,. Hyderabad ... thus obtained are helpful to model the regioselectivity ... compromise to model Diels–Alder reactions involving ...... acceptance.

  4. Investigation of Na-CO{sub 2} Reaction with Initial Reaction in Various Reacting Surface

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Su; Park, Gunyeop; Kim, Soo Jae; Park, Hyun Sun; Kim, Moo Hwan [POSTECH, Pohang (Korea, Republic of); Wi, Myung-Hwan [KAERI, Daejeon (Korea, Republic of)

    2015-10-15

    The reaction products that cause oxidation and erosion are threaten the heat transfer tubes so that it is necessary to investigate Na-CO{sub 2} reaction according to various experimental parameter. Unlike SWR, Na-CO{sub 2} reaction is more complex to deal with reaction kinetics. Since a comprehensive understanding of Na-CO{sub 2} reaction mechanism is crucial for the safety analysis, the reaction phenomenon under the various conditions was investigated. The current issue is to make a database for developing computational code for CO{sub 2} gas leak situation because it is experimentally difficult to analyze the actual accident situation. Most studies on Na-CO{sub 2} interaction reports that chemical reaction is getting vigorous as temperature increased and reactivity is sensitive as temperature change between 400 .deg. C and 600 .deg. C. Therefore, temperature range is determined based on the operating condition (450 - 500 .deg. C) of KALIMER-600 employed as supercritical CO{sub 2} brayton cycle energy conversion system for Na-CO{sub 2} heat exchanger. And next parameter is sodium surface area which contact between sodium and CO{sub 2} when CO{sub 2} is injected into sodium pool in the accident situation. So, the fundamental surface reaction is experimentally studied in the range of 8 - 12cm{sup 2}. Additionally, it has been reported in recent years that CO{sub 2} Flow rate affects reactivity less significantly and CO{sub 2} flow rate is assumed that 5 SLPM (standard liter per minute) is suitable as a basis for a small leakage. The finally selected control parameters is sodium temperature and reacting surface area with constant CO{sub 2} flow rate. Na-CO{sub 2} reaction test is performed for investigating risk of potential accident which contacts with liquid sodium and CO{sub 2}. Amount of reaction is saturated as time passed because of kept a balance between production of solid phase reaction products and amount of diffusivity. These results contribute to make a

  5. Investigation of Na-CO2 Reaction with Initial Reaction in Various Reacting Surface

    International Nuclear Information System (INIS)

    Kim, Hyun Su; Park, Gunyeop; Kim, Soo Jae; Park, Hyun Sun; Kim, Moo Hwan; Wi, Myung-Hwan

    2015-01-01

    The reaction products that cause oxidation and erosion are threaten the heat transfer tubes so that it is necessary to investigate Na-CO 2 reaction according to various experimental parameter. Unlike SWR, Na-CO 2 reaction is more complex to deal with reaction kinetics. Since a comprehensive understanding of Na-CO 2 reaction mechanism is crucial for the safety analysis, the reaction phenomenon under the various conditions was investigated. The current issue is to make a database for developing computational code for CO 2 gas leak situation because it is experimentally difficult to analyze the actual accident situation. Most studies on Na-CO 2 interaction reports that chemical reaction is getting vigorous as temperature increased and reactivity is sensitive as temperature change between 400 .deg. C and 600 .deg. C. Therefore, temperature range is determined based on the operating condition (450 - 500 .deg. C) of KALIMER-600 employed as supercritical CO 2 brayton cycle energy conversion system for Na-CO 2 heat exchanger. And next parameter is sodium surface area which contact between sodium and CO 2 when CO 2 is injected into sodium pool in the accident situation. So, the fundamental surface reaction is experimentally studied in the range of 8 - 12cm 2 . Additionally, it has been reported in recent years that CO 2 Flow rate affects reactivity less significantly and CO 2 flow rate is assumed that 5 SLPM (standard liter per minute) is suitable as a basis for a small leakage. The finally selected control parameters is sodium temperature and reacting surface area with constant CO 2 flow rate. Na-CO 2 reaction test is performed for investigating risk of potential accident which contacts with liquid sodium and CO 2 . Amount of reaction is saturated as time passed because of kept a balance between production of solid phase reaction products and amount of diffusivity. These results contribute to make a database for the SFR safety analysis and additional experiments are needed

  6. Musical taste, employment, education, and global region.

    Science.gov (United States)

    North, Adrian C; Davidson, Jane W

    2013-10-01

    Sociologists have argued that musical taste should vary between social groups, but have not considered whether the effect extends beyond taste into uses of music and also emotional reactions to music. Moreover, previous research has ignored the culture in which participants are located. The present research employed a large sample from five post-industrial global regions and showed that musical taste differed between regions but not according to education and employment; and that there were three-way interactions between education, employment, and region in the uses to which participants put music and also their typical emotional reactions. In addition to providing partial support for existing sociological theory, the findings highlight the potential of culture as a variable in future quantitative research on taste. © 2013 The Scandinavian Psychological Associations.

  7. Entrepreneurship and Employment Stability

    DEFF Research Database (Denmark)

    Failla, Virgilio; Melillo, Francesca; Reichstein, Toke

    2017-01-01

    This paper challenges the conventional belief that entrepreneurship is an unstable career path. Using longitudinal matched employer–employee data from Denmark, the analysis reveals that a transition to entrepreneurship decreases individual's employment turnover tendency. Three explanations...

  8. Veteran Services - Welcome Employers

    Science.gov (United States)

    Assistance Crosswalk websites Transition GPS National Career Readiness Certificate Post Traumatic Stress Credits (PDF) Fidelity Bonding Program National Career Readiness (PDF) Veteran Recruitment State/Federal veteran recruitment process Military Veteran Employment Guide Veterans Hiring Toolkit Other Information

  9. Ametryn degradation by aqueous chlorine: Kinetics and reaction influences

    International Nuclear Information System (INIS)

    Xu Bin; Gao Naiyun; Cheng Hefa; Hu Chenyan; Xia Shengji; Sun Xiaofeng; Wang Xuejiao; Yang Shaogui

    2009-01-01

    The chemical oxidation of the herbicide ametryn was investigated by aqueous chlorination between pH 4 and 10 at a temperature of 25 deg. C. Ametryn was found to react very rapidly with aqueous chlorine. The reaction kinetics can be well described by a second-order kinetic model. The apparent second-order rate constants are greater than 5 x 10 2 M -1 s -1 under acidic and neutral conditions. The reaction proceeds much more slowly under alkaline conditions. The predominant reactions were found to be the reactions of HOCl with neutral ametryn and the charged ametryn, with rate constants equal to 7.22 x 10 2 and 1.58 x 10 3 M -1 s -1 , respectively. The ametryn degradation rate increases with addition of bromide and decreases with addition of ammonia during the chlorination process. Based on elementary chemical reactions, a kinetic model of ametryn degradation by chlorination in the presence of bromide or ammonia ion was also developed. By employing this model, we estimate that the rate constants for the reactions of HOBr with neutral ametryn and charged ametryn were 9.07 x 10 3 and 3.54 x 10 6 M -1 s -1 , respectively. These values are 10- to 10 3 -fold higher than those of HOCl, suggesting that the presence of bromine species during chlorination could significantly accelerate ametryn degradation.

  10. Employers meet employees

    OpenAIRE

    Scheuer, Christian

    2009-01-01

    "Leaping into the future of labor economics: the research potential of linking employer and employee data" is the title of a paper by Daniel S Hammermesh published in Labour Economics in 1999. I quote it here, since it captures much of my motivation for the work included in this thesis. Considering applied micro econometrics and labor economics my main elds of interest, the development of linked employer-employee data that took place in Denmark around the time of the new mille...

  11. Direct Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Austern, N. [University of Pittsburgh, Pittsburgh, PA (United States)

    1963-01-15

    In order to give a unified presentation of one point of view, these lectures are devoted only to a detailed development of the standard theories of direct reactions, starting from basic principles. Discussion is given of the present status of the theories, of the techniques used for practical calculation, and of possible future developments. The direct interaction (DI) aspects of a reaction are those which involve only a few of the many degrees of freedom of a nucleus. In fact the minimum number of degrees of freedom which must be involved in a reaction are those required to describe the initial and final channels, and DI studies typically consider these degrees of freedom and no others. Because of this simplicity DI theories may be worked out in painstaking detail. DI processes concern only part of the wave function for a problem. The other part involves complicated excitations of many degrees of freedom, and gives the compound nucleus (CN) effects. While it is extremely interesting to learn how to separate DI and CN effects in an orderly manner, if they are both present in a reaction, no suitable method has yet been found. Instead, current work stresses the kinds of reactions and the kinds of final states in which DI effects dominate and in which CN effects may almost be forgotten. The DI cross-sections which are studied are often extremely large, comparable to elastic scattering cross-sections. (author)

  12. Deficiency of employability capacity

    Directory of Open Access Journals (Sweden)

    Pelse I.

    2012-10-01

    Full Text Available Young unemployed people have comprised one of the significantly largest groups of the unemployed people in Latvia in recent years. One of the reasons why young people have difficulty integrating into the labour market is the “expectation gap” that exists in the relations between employers and the new generation of workers. Employers focus on capacity-building for employability such individual factors as strength, patience, self-discipline, self-reliance, self-motivation, etc., which having a nature of habit and are developed in a long-term work socialization process, which begins even before the formal education and will continue throughout the life cycle. However, when the socialization is lost, these habits are depreciated faster than they can be restored. Currently a new generation is entering the labour market, which is missing the succession of work socialization. Factors, such as rising unemployment and poverty in the background over the past twenty years in Latvia have created a very unfavourable employability background of “personal circumstances” and “external factors”, which seriously have impaired formation of the skills and attitudes in a real work environment. The study reveals another paradox – the paradox of poverty. Common sense would want to argue that poverty can be overcome by the job. However, the real state of affairs shows that unfavourable coincidence of the individual, personal circumstances and external factors leads to deficit of employability capacity and possibility of marked social and employment deprivation.

  13. Employment of security personnel

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    If a company or institution hires personnel of a security service company to protect its premises, this kind of employment does not mean the company carries on temporary employment business. Within the purview of section 99, sub-section 1 of the BetrVG (Works Constitution Act), the security service personnel is not 'employed' in the proper sense even if the security tasks fulfilled by them are done at other times by regular employees of the company or institution. The court decision also decided that the Works Council need not give consent to employment of foreign security personnel. The court decision was taken for settlement of court proceedings commenced by Institute of Plasma Physics in Garching. In his comments, W. Hunold accedes to the court's decision and discusses the underlying reasons of this decision and of a previous ruling in the same matter by putting emphasis on the difference between a contract for services and a contract for work, and a contract for temporary employment. The author also discusses the basic features of an employment contract. (orig./HP) [de

  14. Advancing intercultural competency: Canadian engineering employers' experiences with immigrant engineers

    Science.gov (United States)

    Friesen, Marcia; Ingram, Sandra

    2013-05-01

    This paper explores Canadian engineering employers' perceptions of and experiences with internationally educated engineers (recent immigrants to Canada) employed in their organisations for varying lengths of time. Qualitative data were collected from employers using focus group methodology. Findings reflected employers' observations of culturally different behaviours and characteristics in their internationally educated employees, employers' reactions to cultural differences ranging from negative attributions to tolerance, and the implementation of largely ad hoc intra-organisational strategies for managing cultural differences in employer-employee relationships. Findings exposed the lack of corporate intercultural competency in the Canadian engineering profession. Equity and gatekeeping implications are discussed.

  15. FACILITATED CHEMICAL SYNTHESIS UNDER ALTERNATE REACTION CONDITIONS

    Science.gov (United States)

    The chemical research in the late 1990's witnessed a paradigm shift towards "environmentally-friendly chemistry" more popularly known as "green chemistry" due to the increasing environmental concerns and legislative requirements to curb the release of chemical waste into the atmo...

  16. Reaction mechanisms

    International Nuclear Information System (INIS)

    Nguyen Trong Anh

    1988-01-01

    The 1988 progress report of the Reaction Mechanisms laboratory (Polytechnic School, France), is presented. The research topics are: the valence bond methods, the radical chemistry, the modelling of the transition states by applying geometric constraints, the long range interactions (ion - molecule) in gaseous phase, the reaction sites in gaseous phase and the mass spectroscopy applications. The points of convergence between the investigations of the mass spectroscopy and the theoretical chemistry teams, as well as the purposes guiding the research programs, are discussed. The published papers, the conferences, the congress communications and the thesis, are also reported [fr

  17. N-Iodosuccinimide-Promoted Hofmann-Löffler Reactions of Sulfonimides under Visible Light.

    Science.gov (United States)

    O'Broin, Calvin Q; Fernández, Patricia; Martínez, Claudio; Muñiz, Kilian

    2016-02-05

    Conditions for an attractive and productive protocol for the position-selective intramolecular C-H amination of aliphatic groups (Hofmann-Löffler reaction) are reported employing sulfonimides as nitrogen sources. N-Iodosuccinimide is the only required promoter for this transformation, which is conveniently initiated by visible light. The overall transformation provides pyrrolidines under mild and selective conditions as demonstrated for 17 different substrates.

  18. The employment effects of sustainable development policies

    International Nuclear Information System (INIS)

    McNeill, Judith M.; Williams, Jeremy B.

    2007-01-01

    This paper argues that it is time for ecological economists to bring the employment impacts of sustainable development policies to the forefront of the research agenda. Important conservation efforts continue to founder because of their perceived employment effects. The paper examines the evidence on the employment impacts of sustainable development policies and argues that maintaining or even increasing employment depends critically on appropriate policy design and attention to the political economy of implementation of policies. The paper concludes that a better understanding of these issues, fair labour market and structural adjustment programs, and especially forward planning to anticipate problem areas, must replace the piecemeal, 'knee-jerk' reactions to environmental issues, such as were evident in Australia during the last federal election. (author)

  19. Allergic reactions

    Science.gov (United States)

    ... that don't bother most people (such as venom from bee stings and certain foods, medicines, and pollens) can ... person. If the allergic reaction is from a bee sting, scrape the ... more venom. If the person has emergency allergy medicine on ...

  20. Implementing public employment policy

    DEFF Research Database (Denmark)

    Larsen, Flemming; Bredgaard, Thomas

    disciplining of the unemployed (work first) (cf.Bredgaard & Larsen, 2005; Sol & Westerweld, 2005). It is, however, remarkable that in the research field there seems to be a division of labour so that changes in public administration and changes in the substance of employment policies are dealt with separately......Like most other areas within welfare policy, the employment and social policy areas are undergoing far-reaching changes in many countries. Partly in the shape of new forms of governance inspired by New Public Management (NPM), partly through new policies oriented towards activation and stronger....... But there is an interesting question to investigate here: whether and if so how, NPM-inspired reforms are related to changes in employment policy towards a work-first approach? Are changes in public management systems created as deliberate policy changes, or do they bring about more indirect and unintended policy changes...

  1. Job Sharing: An Employment Alternative for the Career Services Professional.

    Science.gov (United States)

    Johnson, Louise; Meerdink, Lois A.

    1985-01-01

    Describes and assesses job sharing as an employment alternative for career services professionals. Discusses the job-sharing format with regard to fringe benefits, scheduling, advantages, client reactions, potential problems, and specific factors that contribute to successful job sharing. (BH)

  2. Electrochemical reaction mechanisms under various charge-discharge operating conditions for Li1.2Ni0.13Mn0.54Co0.13O2 in a lithium-ion battery

    Science.gov (United States)

    Konishi, Hiroaki; Hirano, Tatsumi; Takamatsu, Daiko; Gunji, Akira; Feng, Xiaoliang; Furutsuki, Sho; Okumura, Takefumi; Terada, Shohei; Tamura, Kazuhisa

    2018-06-01

    The potential in each state of charge (SOC) during charging of Li1.2Ni0.13Mn0.54Co0.13O2 is higher than that during discharging. In other words, the potential hysteresis occurs between charging and discharging. Furthermore, the potential in each SOC changes according to the charge-discharge operating conditions, indicating that the charge-discharge reaction mechanism is also affected. To clarify the effect of charge-discharge operating conditions on the electrochemical reaction, Li1.2Ni0.13Mn0.54Co0.13O2 was charged and discharged under various charge-discharge operating ranges, and open-circuit potential (OCP), crystal structure, and oxidation states of the transition metals were evaluated by electrochemical measurement, X-ray diffraction (XRD), and X-ray absorption fine structure (XAFS). These results indicate that OCP, lattice parameters, and oxidation states of the transition metals of Li1.2Ni0.13Mn0.54Co0.13O2 in each SOC are not constant. The XRD results indicate that two phases, namely, LiNi0.33Mn0.33Co0.33O2-like and Li2MnO3-like, exist in Li1.2Ni0.13Mn0.54Co0.13O2. For the LiNi0.33Mn0.33Co0.33O2-like phase, the relationship between OCP, lattice parameters, and oxidation states of the transition metals in each SOC is not affected by the charge-discharge operating conditions, indicating that extraction and insertion of lithium ions for the LiNi0.33Mn0.33Co0.33O2-like phase progresses at almost the same potential. Although the extraction and insertion of lithium ions for the Li2MnO3-like phase progresses at almost the same potential in the low-SOC region, the OCP and lattice parameter in each SOC in the high-SOC region are not constant. Therefore, the extraction of lithium ions from the Li2MnO3-like phase in the high-SOC region causes the potential hysteresis of Li1.2Ni0.13Mn0.54Co0.13O2.

  3. Epidemiological approach to the study of conditions of employment, labor and health in the Colombian immigrant population of Spain / Aproximación epidemiológica al estudio de las condiciones de empleo, trabajo y salud en la población inmigrante colombiana en España

    Directory of Open Access Journals (Sweden)

    Andrés A. Agudelo-Suárez

    2012-10-01

    Full Text Available The objective of this paper is to analyze the employment, work conditions, and associated health problems of Colombian immigrants. Methods: an epidemiological and descriptive study was conducted in the Colombian immigrant population (employed and unemployed by means of a personal survey in a sample of immigrants. The survey concerned personal characteristics, working conditions, and health indicators. Results: there is an important percentage of immigrants with a temporary contract or without any contract, and working more than 40 hours per week. One fifth of the immigrants do not have social security coverage. The great majority of women (92% have incomes under 1,200 euros/month. Immigrants reported discrimination in work and social spaces. Immigrants report several health problems, with some differences between genders. Almost one third has not received information on accident prevention and health issues. Situations of social precariousness are demonstrated, which require strategies to guarantee social protection mechanisms for this entire collective.

  4. Employment certificates on HRT

    CERN Multimedia

    HR Department

    2008-01-01

    As part of the ongoing drive to simplify and streamline administrative procedures and processes, the IT and HR Departments have made employment certificates available on a self-service basis on the HRT application, in the main menu under "My self services". All members of the personnel can thus obtain a certificate of employment or association, in French or in English, for the present or past contractual period. The HR Department’s Records Office remains responsible for issuing any special certificates that might be required. IT-AIS (Administrative Information Services) HR-SPS (Services, Procedures & Social) Records Office – Tel. 73700

  5. Radiation protection - the employer

    International Nuclear Information System (INIS)

    Goldfinch, E.

    1983-01-01

    A brief report is given of a paper presented at the symposium on 'Radiation and the Worker - where do we go from here' in London 1983. The paper concerned the employers' viewpoint on the draft of the proposed Ionising Radiations Regulations in the Health and Safety Commission Consultative Document. It was concluded that there was already a very good standard of radiological protection in the UK and that any improvements could therefore only be fringe improvements, although the cost to the employer of introducing and implementing the new proposed Regulations was bound to be high. (U.K.)

  6. The Glaser–Hay reaction

    DEFF Research Database (Denmark)

    Vilhelmsen, Mie Højer; Jensen, Jonas; Tortzen, Christian

    2013-01-01

    The oxidative Glaser–Hay coupling of two terminal alkynes to furnish a butadiyne is a key reaction for acetylenic scaffolding. Although the reaction is performed under rather simple conditions [CuCl/TMEDA/O2 (air)], the mechanism is still under debate. Herein we present detailed studies...... on the scope of this reaction by using both 13C NMR and UV/Vis spectroscopic methods. The former method was used to study the kinetics of the coupling of aryl-substituted alkynes as the aryl carbon resonances of the reactants and products have similar NOEs and relaxation times. The reaction was found...... to be zero-order with respect to the terminal alkyne reactant under standard preparative conditions. Moreover, as the reaction proceeded, a clear change to slower reaction kinetics was observed, but it was still apparently zero-order. The onset of this change was found to depend on the catalyst loading...

  7. Employers' attitudes to employment of people with epilepsy: still the same old story?

    Science.gov (United States)

    Jacoby, Ann; Gorry, Joanne; Baker, Gus A

    2005-12-01

    One area of life quality known to be compromised by having epilepsy is employment, and one factor contributing to the employment problems of people with epilepsy (PWE) is employer attitudes. Much research on this topic is now outdated and given the changing legal, medical, and social contexts in which PWE live, we therefore reexamined employer attitudes in the United Kingdom. A mail survey of a random sample of U.K. companies selected to be representative of the 14 U.K. economic regions and proportional to the number of employees. The overall response rate was 41% (n = 204). Twenty-six percent of respondents reported having experience of employing PWE. Sixteen percent considered that there were no jobs in their company suitable for PWE; 21% thought employing PWE would be "a major issue." Employers were uniformly of the view that PWE, even when in remission, should disclose their condition to a prospective employer. Seizure severity, frequency, and controllability were all considered important features of epilepsy in the context of employment. Epilepsy created high concern to around half of employers, including the likelihood of it being linked to a work-related accident. Employers were willing to make accommodations for PWE, in particular job sharing, temporary reassignment of duties, and flexible working hours. Attitudes to employment of PWE were influenced by company size and type and previous experience of doing so. We conclude that it is still the same old story for employers' attitudes toward PWE, though happily for PWE, with some room for optimism.

  8. Modified aluminoplatinum catalysts for the reaction of cyclotrimerization of ethylene

    Energy Technology Data Exchange (ETDEWEB)

    Vasina, T V; Bragin, O V; Lutovinova, V N; Preobrazhenskii, A V; Savostin, Yu A

    1981-01-01

    The influence of additions of various metals (Sc, Zr, Sn, and Re) on the dispersity of Pt particles on an Al-Pt catalyst for the reaction of ethylene cyclotrimerization was studied. It was shown that introduction of additives of different natures and concentrations, employment of different conditions for H/sub 2/ reduction and thermal treatment of the catalyst, and other things allow the dispersity of the Pt on the catalyst to be varied within the range 0.06-1 GAMMA (GAMMA - the fraction of Pt accessible for reaction on the surface of the support). For most of the studied catalysts a symbiotic relation between the dispersity of the Pt particles and the activity of the A1-Pt catalyst in the studied reaction is observed.

  9. Stability analysis of impulsive fuzzy cellular neural networks with distributed delays and reaction-diffusion terms

    International Nuclear Information System (INIS)

    Li Zuoan; Li Kelin

    2009-01-01

    In this paper, we investigate a class of impulsive fuzzy cellular neural networks with distributed delays and reaction-diffusion terms. By employing the delay differential inequality with impulsive initial conditions and M-matrix theory, we find some sufficient conditions ensuring the existence, uniqueness and global exponential stability of equilibrium point for impulsive fuzzy cellular neural networks with distributed delays and reaction-diffusion terms. In particular, the estimate of the exponential converging index is also provided, which depends on the system parameters. An example is given to show the effectiveness of the results obtained here.

  10. Title: Elucidation of Environmental Fate of Artificial Sweeteners (Aspartame, Acesulfame K and Saccharin) by Determining Bimolecular Rate Constants with Hydroxyl Radical at Various pH and Temperature Conditions and Possible Reaction By-Products

    Science.gov (United States)

    Teraji, T.; Arakaki, T.; Suzuka, T.

    2012-12-01

    Use of artificial sweeteners in beverages and food has been rapidly increasing because of their non-calorie nature. In Japan, aspartame, acesulfame K and sucralose are among the most widely used artificial sweeteners. Because the artificial sweeteners are not metabolized in human bodies, they are directly excreted into the environment without chemical transformations. We initiated a study to better understand the fate of artificial sweeteners in the marine environment. The hydroxyl radical (OH), the most potent reactive oxygen species, reacts with various compounds and determines the environmental oxidation capacity and the life-time of many compounds. The steady-state OH concentration and the reaction rate constants between the compound and OH are used to estimate the life-time of the compound. In this study, we determine the bimolecular rate constants between aspartame, acefulfame K and saccharin and OH at various pH and temperature conditions using a competition kinetics technique. We use hydrogen peroxide as a photochemical source of OH. Bimolecular rate constant we obtained so far for aspartame was (2.6±1.2)×109 M-1 s-1 at pH = 3.0 and (4.9±2.3)×109 M-1 s-1 at pH = 5.5. Little effect was seen by changing the temperatures between 15 and 40 oC. Activation energy (Ea) was calculated to be -1.0 kJ mol-1 at pH = 3.0, +8.5 kJ mol-1 at pH = 5.5, which could be regarded as zero. We will report bimolecular rate constants at different pHs and temperatures for acesulfame K and saccharin, as well. Possible reaction by-products for aspartame will be also reported. We will further discuss the fate of aspartame in the coastal environment.

  11. Disability Employment 101

    Science.gov (United States)

    US Department of Education, 2007

    2007-01-01

    Business is about productivity and maintaining a competitive advantage. To do this, business needs qualified workers. Hiring people with disabilities adds value to a business and will attract new customers. Disability is not inability. Employers can make sound business decisions and gain a competitive advantage by using this guide to increase the…

  12. Discrimination in Employment

    Science.gov (United States)

    Abzug, Bella

    1975-01-01

    This testimony, before a public hearing of the New York City Commission on Human Rights in May 1974, expressly focuses on discrimination in employment, asserting that this has had the most direct effect on minorities and women in the country; while legal protections have grown stronger, they have not been used effectively. (Author/JM)

  13. Governing EU employment policy

    DEFF Research Database (Denmark)

    Sørensen, Eva; Triantafillou, Peter; Damgaard, Bodil

    2015-01-01

    In the European Union (EU), employment policy is a prerogative of the member states. Therefore the EU's ability to govern in this area depends on its capability to involve national governments and relevant stakeholders in a collaborative effort to formulate and implement shared policy objectives....... of collaboration, the implementation phase mainly consists in the less demanding forms of cooperation and coordination....

  14. Employment Relations in Denmark

    DEFF Research Database (Denmark)

    Madsen, Jørgen Steen; Due, Jesper Jørgen; Andersen, Søren Kaj

    2011-01-01

    Jørgen Steen Madsen, Jesper Due og Søren Kaj Andersen har skrevet et kapitel om udviklingen i dansk arbejdsmarkedsregulering til bogen International and Comparative Employment Relations, redigeret af Greg Bamber, Russell Lansbury og Nick Wailes. Bogen indeholder bidrag, der præsenterer og...

  15. Employment Challenges in Kenya

    African Journals Online (AJOL)

    Dr Kazungu

    of foreigners in rural trade, use of work permits to limit employment of expatriates, .... as social and trade union protection, job security, and wage negotiations to the worker. .... are Republic of Korea (1960–2001); Malaysia (1967–1997); Malta ...

  16. Transitional Employment Programs.

    Science.gov (United States)

    Dulle, Paul J.; And Others

    The paper examines the need and implementation of transitional employment programs for handicapped youth. Effects on the handicapped of future automation are considered along with the need for school-business cooperation to prepare for the future. The importance of initial success in any innovation is noted. A Chicago transitional employment…

  17. Policies for full employment

    DEFF Research Database (Denmark)

    de Koning, Jaap; Layard, Richard; Nickel, Stephen

    European unemployment is too high, and employment is too low. Over 7½ per cent of Europe's workforce is unemployed, and only two thirds of people aged 15-64 are in work. At the Lisbon summit two years ago the heads of government set the target that by 2010 the employment rate should rise from 64...... per cent to at least 70 per cent. And for older workers between 55 and 64 the employment rate should rise from 38 per cent to at least one half. These are ambitious targets. They will require two big changes: more people must seek work, and among those seeking work a higher proportion must get a job....... So we need higher participation, and (for full employment) we need a much lower unemployment rate. Can it be done? A mere glance at the experience of different European countries shows that it can. As Table 1 shows, four E.U. countries already exceed the overall target for 2010 (Britain, Denmark...

  18. Implementing the employability agenda

    DEFF Research Database (Denmark)

    Lee, Donna; Snaith, Holly Grace; Foster, Emma

    2014-01-01

    whether, and how, colleagues in politics and international relations (IR) had taken ownership of student employability at the level of the curriculum. In the article, the key findings of the research are summarised. There is also discussion of the (sometimes troubling) professional implications...

  19. Industrialisation, Exports and Employment.

    Science.gov (United States)

    Sabolo, Yves

    1980-01-01

    After reviewing trends in industrial production, exports, and employment in the Third World since 1960, the author discusses industrialization strategies based on the local processing of raw materials for export. Such processing has proved to be a major factor in job creation. (Author/SK)

  20. The Employment Mismatch

    Science.gov (United States)

    Fischer, Karin

    2013-01-01

    Employers value a four-year college degree, many of them more than ever. Yet half of those surveyed recently by "The Chronicle" and American Public Media's "Marketplace" said they had trouble finding recent graduates qualified to fill positions at their company or organization. Nearly a third gave colleges just fair to poor marks for producing…

  1. Reaction chemistry of cerium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-01

    It is truly ironic that a synthetic organic chemist likely has far greater knowledge of the reaction chemistry of cerium(IV) than an inorganic colleague. Cerium(IV) reagents have long since been employed as oxidants in effecting a wide variety of organic transformations. Conversely, prior to the late 1980s, the number of well characterized cerium(IV) complexes did not extend past a handful of known species. Though in many other areas, interest in the molecular chemistry of the 4f-elements has undergone an explosive growth over the last twenty years, the chemistry of cerium(IV) has for the most part been overlooked. This report describes reactions of cerium complexes and structure.

  2. The impact of Chilean migration on employment in Patagonia.

    Science.gov (United States)

    Cariola Sanz, L

    1989-06-01

    This paper discusses the employment situation of Chilean migrant workers, their impact on labor markets in Patagonia, Argentina, and the government's past and projected responses to this phenomenon. In 1980, Chilean inhabitants of patagonia comprised 11% of the area's population. Chilean migration to patagonia was closely linked to economic activities that began to flourish in the 20th century, such as livestock raising, fruit and vegetable cultivation, and mining for coal and petroleum. No Chilean migrants work in a wide range of sectors. In Patagonia's southern provinces availability and ability to withstand rigorous climate conditions are the main factors which account for the prevalence of Chilean manpower. Chilean migrants do not in general displace local manpower. Legislation and the permeability of the border ensure that most workers enter the country as tourists. Clandestine migration is not an issue. Illegal migrants have provoked negative reactions for several reasons: 1) they comprise a marginal population without formal citizenship; 2) being employed as clandestine workers, they pay no social security, nor do their employers; 3) being illegal, they are obliged to accept lower wages and inferior working conditions which creates unfair competition within labor markets; and 4) as a result of these conditions, xenophobic and endophobic attitudes in relations with Argentine nationalists are reinforced. The government has attempted to solve these problems through various measures. Beginning in 1934, most foreigners entered Argentina with a tourist visa, becoming illegal when they stayed beyond authorized limits. Several measures over the years provided amnesty to illegal migrants. Currently, the law promotes immigration, monitors the admission of foreigners to the country and stipulates their rights and obligations. The law lists 115 articles on immigration promotion and on regulation of the movements of foreigners. Because of the present economic crisis in

  3. KINETIC RESOLUTION OF ALCOHOLS IN AN ASYMMETRIC MITSUNOBU REACTION USING CHIRAL NONRACEMIC 1,3,2-DIOXAPHOSPHEPANES

    NARCIS (Netherlands)

    Hulst, Ron; Basten, Arjan van; Fitzpatrick, Kevin; Kellogg, Richard M.

    1995-01-01

    Non-racemic chiral trivalent phosphorus derivatives 1 and 2 when employed under Mitsunobu reaction conditions, induce esterification between racemic alcohols and acids with moderate enantiospecificity (up to 39%). At the expense of high conversion, the alcohols can be obtained in high ee (> 99%).

  4. Kinetics and optimization on discoloration of dyeing wastewater by schorl-catalyzed fenton-like reaction

    Directory of Open Access Journals (Sweden)

    Xu Huan-Yan

    2014-01-01

    Full Text Available Kinetics and optimization on the discoloration of an active commercial dye, Argazol Blue BFBR (ABB by heterogeneous Fenton-like reaction catalyzed by natural schorl were investigated in this study. Kinetic investigations revealed that the first-order kinetic model was more favorable to describe the discoloration of ABB at different reaction conditions than the second-order and Behnajady-Modirshahla-Ghanbery models. The relationship between the reaction rate constant k and reaction temperature T followed the Arrhenius equation, with the apparent activation energy Ea of 51.31kJ•mol-1. The central composite design under the response surface methodology was employed for the experimental design and optimization of the ABB discoloration process. The significance of a second order polynomial model for predicting the optimal values of ABB discoloration was evaluated by the analysis of variance and 3D response surface plots for the interactions between two variables were constructed. Then, the optimum conditions were determined.

  5. Toluene pyrolysis studies and high temperature reactions of propargyl chloride

    Energy Technology Data Exchange (ETDEWEB)

    Kern, R.D.; Chen, H.; Qin, Z. [Univ. of New Orleans, LA (United States)

    1993-12-01

    The main focus of this program is to investigate the thermal decompositions of fuels that play an important role in the pre-particle soot formation process. It has been demonstrated that the condition of maximum soot yield is established when the reaction conditions of temperature and pressure are sufficient to establish a radical pool to support the production of polyaromatic hydrocarbon species and the subsequent formation of soot particles. However, elevated temperatures result in lower soot yields which are attributed to thermolyses of aromatic ring structures and result in the bell-shaped dependence of soot yield on temperature. The authors have selected several acyclic hydrocarbons to evaluate the chemical thermodynamic and kinetic effects attendant to benzene formation. To assess the thermal stability of the aromatic ring, the authors have studied the pyrolyses of benzene, toluene, ethylbenzene, chlorobenzene and pyridine. Time-of-flight mass spectrometry (TOF) is employed to analyze the reaction zone behind reflected shock waves. Reaction time histories of the reactants, products, and intermediates are constructed and mechanisms are formulated to model the experimental data. The TOF work is often performed with use of laser schlieren densitometry (LS) to measure density gradients resulting from the heats of various reactions involved in a particular pyrolytic system. The two techniques, TOF and LS, provide independent and complementary information about ring formation and ring rupture reactions.

  6. An efficient catalyst for asymmetric Reformatsky reaction

    Indian Academy of Sciences (India)

    rate enantioselectivity using N,N-dialkylnorephedrines as chiral ligands. ..... temperatures also, there was no product conversion. ... Optimization of reaction conditions for asymmetric Reformatsky reaction between benzaldehyde and α-.

  7. Multiple Employer Welfare Arrangements

    Science.gov (United States)

    1992-01-01

    Sponsors in the Private Nonfarm Sector in the United States, 1978-79," Volume IV, Description and Analysis of Plans and Plan Sponsors, NTIS # PB81-180366...Labor finds to be collectively bargained plans, and those organized by rural electrical cooperatives and rural telephone cooperatives. Thus, except for...their existence and generally higher cost than uninsured plans no doubt contributed to the development of other types of multiple employer

  8. Authenticity in Employment Relations

    OpenAIRE

    Tackney, Charles T.

    2014-01-01

    This research takes up the concept of authenticity as a criterion variable for theology of the workplace analysis, a domain which explores employment parameters in light of religious teaching on the social question at national, organizational or firm-specific levels. Following a review of the concept in Western culture, philosophy, and management studies, Religious Society of Friends (Quaker) and Roman Catholic social teachings are investigated for positively correlative data to help develop ...

  9. Soldiers’ employment attitude and employability: An exploratory study

    Directory of Open Access Journals (Sweden)

    Peng Gao

    2015-04-01

    Full Text Available Purpose: Nowadays it is very difficult for Chinese retired soldiers to find proper jobs, and the primary reason is the significant gap between job requirements and soldiers owned job skills. Therefore, it is very important to improve the soldiers’ job skills and enhance their understanding of employment.Design/methodology/approach: This paper expands the study scope from the soldiers’ job skills to the employability, initiatively introduces the employment attitude which has obvious impact on the employment of soldiers, and analyses the influence that employment attitude can play on employability. At last, this paper develops statistical method to find the relationship between soldiers’ employment attitude and employability.Findings: The empirical analysis shows that soldiers’ employment attitude has the positive linkage with employability, which makes the employment attitude a measurable variable for the employability rather than an absolute standard.Research limitations/implications: According to the research purpose, more variables should be considered in the model, consequently, there are only three indicators to describe solders’ employment attitude and four indicators to describe solders’ employability.Originality/value: This paper takes research on soldiers’ employability in a new perspective. The soldiers’ employment attitude is served as the entry point, showing the influence that soldiers’ employment attitude has on employability.

  10. Environment, employment and development

    International Nuclear Information System (INIS)

    Bhalla, A.S.

    1992-01-01

    It is generally recognised that the question of sustainable development is a global problem, emphasizing the increasingly interdependent nature of relationships among nations. Solutions to the problem are as much political as they are economic and technological. Notwithstanding the deepening and widening of the debate on sustainable development, its implications for employment - a major concern of the ILO under its World Employment Programme - have remained largely unexplored. This volume, therefore, has a very modest objective, namely to place the employment question on the policy agenda in the context of the current debate on environment and development. The design of environmental policies should allow for the differences that exist between countries with a high level of development and technological dynamism and those with a low level of development and low technological capability. One must also recognize the costs imposed by adjustment and the consequent distributional impact. In the long term, technology choice plays a crucial role in promoting sustainable development in both industrialized and developing countries. It is not only environment-friendly technologies that need to be developed and diffused; in the case of the least developed countries, technological transformation needs to be accelerated in order to minimise their dependence on natural resources for economic growth. Refs, figs and tabs

  11. BULGARIAN EMPLOYMENT POLICY: PRIORITIES AND DIRECTIONS 2017

    Directory of Open Access Journals (Sweden)

    Ekaterina Arabska

    2017-04-01

    Full Text Available Development of labor market and employment policy in Bulgaria in contemporary dynamic conditions of social and economic life is in close relation to the European policies and programs and the needs of creating conditions for raising the level of employability of some special target groups on the labor market determined as the most vulnerable and needing particular measures of support. Current study makes analyses of priorities and directions in Bulgarian national employment policy for 2017 as set into the National action plan on employment considering a number of strategic and legislative documents on both national and European level. The general conclusions are focused on the systematization of actions and the importance of social dialogue.

  12. Quasielastic reactions

    International Nuclear Information System (INIS)

    Hansen, O.

    1983-01-01

    A brief review is presented of the experimental and theoretical situation regarding transfer reactions and inelastic scattering. In the first category there is little (very little) precision data for heavy projectiles and consequently almost no experience with quantitative theoretical analysis. For the inelastic scattering the rather extensive data strongly supports the coupled channels models with collective formfactors. At the most back angles, at intensities about 10 -5 of Rutherford scattering, a second, compound-like mechanism becomes dominant. The description of the interplay of these two opposite mechanisms provides a new challenge for our understanding

  13. Employment and winter construction

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Larsen, Jacob Norvig

    2011-01-01

    Reduced seasonal building activity in the construction sector is often assumed to be related to hard winter conditions for building activities and poor working conditions for construction workers, resulting in higher costs and poor quality of building products, particularly in the northern hemisp...... of contracts for workers is more likely to explain differences in seasonal activity than climatic or technological factors....

  14. Asymmetric H-D exchange reactions of fluorinated aromatic ketones

    KAUST Repository

    Zhao, Yujun; Lim, XiaoZhi; Pan, Yuanhang; Zong, Lili; Feng, Wei; Tan, Choonhong; Huang, Kuo-Wei

    2012-01-01

    Chiral bicyclic guanidine catalyzes the asymmetric H-D exchange reactions. Up to 30% ee was achieved. DFT calculations were employed to elucidate and explain the origin of the reaction's stereoselectivity. © 2012 The Royal Society of Chemistry.

  15. Sequential evolution of different phases in metastable Gd(2-x)Ce(x)Zr(2-x)Al(x)O7 (0.0 ≤ x ≤ 2.0) system: crucial role of reaction conditions.

    Science.gov (United States)

    Shukla, Rakesh; Sayed, Farheen N; Phapale, Suhas; Mishra, Ratikant; Tyagi, Avesh K

    2013-07-15

    The Gd(2-x)Ce(x)Zr(2-x)Al(x)O7 (0.0 ≤ x ≤ 2.0) series was synthesized by the gel combustion method. This system exhibited the presence of a fluorite-type phase, along with a narrow biphasic region, depending upon the Ce/Gd content in the sample. Thermal stability of these new compounds under oxidizing and reducing conditions has been investigated. The products obtained on decomposition of Gd(2-x)Ce(x)Zr(2-x)Al(x)O7 in oxidizing and reducing conditions were found to be entirely different. It was observed that in air the fluorite-type solid solutions of Gd(2-x)Ce(x)Zr(2-x)Al(x)O7 composition undergo phase separation into perovskite GdAlO3 and fluorite-type solid solutions of Gd-Ce-Zr-O or Ce-Zr-Al-O depending upon the extent of Ce and Al substitution. On the other hand, Gd(2-x)Ce(x)Zr(2-x)Al(x)O7 samples on heating under reducing conditions show a phase separation to CeAlO3 perovskite and a defect-fluorite of Gd2Zr2O7. The extent of metastability for a typical composition of Gd(1.2)Ce(0.8)Zr(1.2)Al(0.8)O7 (nano), Gd(1.2)Ce(0.8)Zr(1.2)Al(0.8)O(6.6) (heated under reduced conditions), Gd(1.2)Ce(0.8)Zr(1.2)Al(0.8)O7 (heated in air at 1200 °C) has been experimentally determined employing a high temperature Calvet calorimeter. On the basis of thermodynamic stability data, it could be inferred that the formation of a more stable compound in the presence of two competing cations (i.e., Gd(3+) and Ce(3+)) is guided by the crystallographic stability.

  16. Full Employment in Industrialized Countries.

    Science.gov (United States)

    Britton, Andrew

    1997-01-01

    Argues that full employment must be acceptable on both social and economic grounds. Examines profound changes in industrialized economies since the 1970s and the diversity of employment contracts. Suggests that difficult policy decisions surround full employment. (SK)

  17. Nuclear reactions

    International Nuclear Information System (INIS)

    Corner, J.; Richardson, K.; Fenton, N.

    1990-01-01

    Nuclear reactions' marks a new development in the study of television as an agency of public policy debate. During the Eighties, nuclear energy became a major international issue. The disasters at Three-mile Island and Chernobyl created a global anxiety about its risks and a new sensitivity to it among politicians and journalists. This book is a case-study into documentary depictions of nuclear energy in television and video programmes and into the interpretations and responses of viewers drawn from many different occupational groupings. How are the complex and specialist arguments about benefit, risk and proof conveyed through the different conventions of commentary, interview and film sequence? What symbolic associations does the visual language of television bring to portrayals of the issue? And how do viewers make sense of various and conflicting accounts, connecting what they see and hear on the screen with their pre-existing knowledge, experience and 'civic' expectations. The authors examine some of the contrasting forms and themes which have been used by programme makers to explain and persuade, and then give a sustained analysis of the nature and sources of viewers' own accounts. 'Nuclear Reactions' inquires into the public meanings surrounding energy and the environment, spelling out in its conclusion some of the implications for future media treatments of this issue. It is also a key contribution to the international literature on 'television knowledge' and the processes of active viewing. (author)

  18. Cycloadditions of ketene acetals under microwave irradiation in solvent-free conditions

    International Nuclear Information System (INIS)

    Diaz-Ortiz, A.; Diez-Barra, E.; La Hoz, A. De; Prieto, P.; Moreno, A.

    1994-01-01

    When subjected to microwave irradiation ketene acetals undergo 1.3-dipolar and hetero-Diels-Alder cycloadditions within 5-12 min to give excellent yields of easily purified heterocyclic products. This efficient and rapid synthesis has the advantage of employing milder reaction conditions than those of classical thermal heating. (author)

  19. 2007 Veterans Employability Research Survey

    Data.gov (United States)

    Department of Veterans Affairs — The 2007 Veterans Employability Research Survey (VERS) was conducted to determine the factors that impact veterans' employability resulting from participation in the...

  20. Difusão de contaminantes em condições de vento fraco empregando um modelo estocástico Lagrangeano Difusion of contaminants in low wind conditions employing a Lagrangian stochastic model

    Directory of Open Access Journals (Sweden)

    Andréa Ucker Timm

    2009-09-01

    Full Text Available Um modelo estocástico Lagrangeano é utilizado para simular a dispersão e o transporte de contaminantes, sob condições estáveis, com velocidade do vento fraco, no experimento traçante realizado no Idaho National Engineering Laboratory (INEL. Neste trabalho é testada uma nova parametrização dos parâmetros que representam as freqüências associadas ao fenômeno de meandro do vento, presentes nas equações de Langevin para as componentes do vento horizontal. Esta nova parametrização é descrita em termos de uma quantidade adimensional que controla a freqüência de oscilação de meandro do vento e da escala de tempo, associada às estruturas coerentes em uma turbulência bem desenvolvida. As simulações demonstram que o modelo Lagrangeano considerado, incorporando esta nova parametrização, reproduz corretamente a difusão de escalares passivos em uma camada limite atmosférica estável com velocidade do vento fraco.A Lagrangian stochastic particle model is utilized to simulate the dispersion and the transport of contaminants under low wind stable conditions in the tracer experiment carried in the Idaho National Engineering Laboratory (INEL. In this work a new parameterization for the parameters representing the frequencies associated to the meandering phenomenon is tested. The new parameterization is expressed in terms of a non-dimensional quantity that controls the frequencies of the meandering oscillation and of the time scale associated to a coherent structure in a fully developed turbulence. The simulations show that the considered Lagrangian model, incorporating this new parameterization, reproduces correctly the diffusion of passive scalars in a low wind speed stable atmospheric boundary layer.

  1. Reaction of hydrogen atoms with acrylaldehyde

    International Nuclear Information System (INIS)

    Koda, Seiichiro; Nakamura, Kazumoto; Hoshino, Takashi; Hikita, Tsutomu

    1978-01-01

    The reaction of hydrogen atoms with acrylaldehyde was investigated in a fast flow reactor equipped with a time-of-flight type mass spectrometer under reduced pressure. Main reaction products were carbon monoxide, ethylene, ethane, methane, and propanal. Consideration of the distributions of the reaction products under various reaction conditions showed that hydrogen atoms attacked the C=C double bond, especially its inner carbon side under reduced pressure. Resulting hot radicals caused subsequent reactions. The relative value of the apparent bimolecular rate constant of the reaction against that of trans-2-butene with hydrogen atoms was 1.6+-0.2, which supported the above-mentioned initial reaction. (auth.)

  2. Leaving Employment to Entrepreneurship

    DEFF Research Database (Denmark)

    Rocha, Vera; Carneiro, Anabela; Varum, Celeste

    : the relative inattention paid to other human resources beyond the founder, and the hetero-geneous context where employee startups may be established. We use a rich matched employer-employee dataset for Portugal, and estimate a multi-stage model addressing the issues of self-selection in entrepreneurship...... outcomes of arrival fi rms, and also for developing theories on labor markets for entrepreneurship. It also constitutes an important step towards unpacking the mechanisms through which mobile human capital affects the performance of receiving firms....

  3. Challenging Scandinavian employment relations

    DEFF Research Database (Denmark)

    Ibsen, Christian Lyhne; Larsen, Trine Pernille; Madsen, Jørgen Steen

    2011-01-01

    and employment relations in the Danish, Norwegian and Swedish public sector. In this paper, we argue that although differences exist across the Scandinavian countries, it is evident that they have managed to adopt and implement NPM-inspired reforms without dismantling their universal welfare services and strong......Building on the convergence/divergence approach, this paper examines whether recent new public management (NPM) inspired reforms entailing inter alia cutbacks in the public sector, marketisation and management by performance measures have had significant implications for service provision...... traditions of collective bargaining in the public sector. However, this restructuring is taking its toll on the work environment....

  4. Graduate Employability: A Conceptual Framework for Understanding Employers' Perceptions

    Science.gov (United States)

    Cai, Yuzhuo

    2013-01-01

    This study provides a conceptual framework for understanding what employers think about the value of graduates with similar educational credentials in the workplace (their employability), using insights from the new institutionalism. In this framework, the development of employers' beliefs about graduates' employability is broken into a number of…

  5. Laboratory study on new particle formation from the reaction OH + SO2: influence of experimental conditions, H2O vapour, NH3 and the amine tert-butylamine on the overall process

    Directory of Open Access Journals (Sweden)

    J. Curtius

    2010-08-01

    Full Text Available Nucleation experiments starting from the reaction of OH radicals with SO2 have been performed in the IfT-LFT flow tube under atmospheric conditions at 293±0.5 K for a relative humidity of 13–61%. The presence of different additives (H2, CO, 1,3,5-trimethylbenzene for adjusting the OH radical concentration and resulting OH levels in the range (4–300 ×105 molecule cm−3 did not influence the nucleation process itself. The number of detected particles as well as the threshold H2SO4 concentration needed for nucleation was found to be strongly dependent on the counting efficiency of the used counting devices. High-sensitivity particle counters allowed the measurement of freshly nucleated particles with diameters down to about 1.5 nm. A parameterization of the experimental data was developed using power law equations for H2SO4 and H2O vapour. The exponent for H2SO4 from different measurement series was in the range of 1.7–2.1 being in good agreement with those arising from analysis of nucleation events in the atmosphere. For increasing relative humidity, an increase of the particle number was observed. The exponent for H2O vapour was found to be 3.1 representing an upper limit. Addition of 1.2×1011 molecule cm−3 or 1.2×1012 molecule cm−3 of NH3 (range of atmospheric NH3 peak concentrations revealed that NH3 has a measureable, promoting effect on the nucleation rate under these conditions. The promoting effect was found to be more pronounced for relatively dry conditions, i.e. a rise of the particle number by 1–2 orders of magnitude at RH = 13% and only by a factor of 2–5 at RH = 47% (NH3 addition: 1.2×1012 molecule cm−3. Using the amine tert-butylamine instead of NH3, the enhancing impact of the base for nucleation and particle growth appears to be stronger. Tert-butylamine addition of about 1010 molecule cm−3 at RH = 13% enhances particle formation by about two orders of magnitude, while for NH3 only a small or negligible

  6. 24 CFR 6.5 - Discrimination prohibited-employment.

    Science.gov (United States)

    2010-04-01

    .... Terms and conditions of employment include advertising, interviewing, selection, promotion, demotion, transfer, recruitment and advertising, layoff or termination, pay or other compensation, including benefits...

  7. Spallation reactions; Reactions de spallation

    Energy Technology Data Exchange (ETDEWEB)

    Cugon, J.

    1996-12-31

    Spallation reactions dominate the interactions of hadrons with nuclei in the GeV range (from {approx} 0.1 to {approx} 10 GeV). They correspond to a sometimes important ejection of light particles leaving most of the time a residue of mass commensurate with the target mass. The main features of the experimental data are briefly reviewed. The most successful theoretical model, namely the intranuclear cascade + evaporation model, is presented. Its physical content, results and possible improvements are critically discussed. Alternative approaches are shortly reviewed. (author). 84 refs.

  8. How do employers cope with an ageing workforce?: Views from employers and employees

    Directory of Open Access Journals (Sweden)

    Hendrik P. Van Dalen

    2010-06-01

    Full Text Available How age-conscious are human resource policies? Using a survey of Dutch employers, we examine how employers deal with the prospect of an ageing work force. We supplement our analysis with an additional survey of Dutch employees to compare human resource policies to practices. Results show that a small minority of employers are taking measures to enhance productivity (training programmes or bring productivity in line with pay (demotion. Personnel policies tend to 'spare' older workers: giving them extra leave, early retirement, or generous employment protection: older workers who perform poorly are allowed to stay, whereas younger workers under similar conditions are dismissed.

  9. Authenticity in Employment Relations

    DEFF Research Database (Denmark)

    Tackney, Charles Thomas

    This research takes up the concept of authenticity as a criterion variable for theology of the workplace analysis, a domain which explores employment parameters in light of religious teaching on the social question at national, organizational or firm-specific levels. Following a review of the con......This research takes up the concept of authenticity as a criterion variable for theology of the workplace analysis, a domain which explores employment parameters in light of religious teaching on the social question at national, organizational or firm-specific levels. Following a review...... of the concept in Western culture, philosophy, and management studies, Religious Society of Friends (Quaker) and Roman Catholic social teachings are investigated for positively correlative data to help develop the criterion variable. From the literature review of concept and historical data in both traditions...... analysis should complement and support corporate social responsibility, management spirituality, authentic leadership / authentic follower, and other secular research by offering a research methods bridge between empirically grounded theology and secular studies, with the common goal of improving workplace...

  10. Life Sciences and employability

    Directory of Open Access Journals (Sweden)

    Wynand J. Boshoff

    2012-03-01

    Full Text Available This article addresses unemployment in rural areas. South Africa is also characterised by skills shortage and high unemployment figures, especially in rural areas as compared to urban areas. The institutional reality of education is that every rural village hosts a high school which is primarily engaged in preparing learners for further studies, whilst the Further Training Colleges (previously known as technical colleges are mainly located in the larger centres. It is with this scenario as a backdrop that the possible role of high schools to alleviate the problem is being argued. It is clear that rural employers do not expect from school leavers to be in possession of applicable knowledge, but rather to be in possession of the ability as well as certain personal characteristics that would make them employable. Unfortunately, however, this is not always found in young persons who have completed their schooling successfully. Life Sciences educators can render a valuable service should certain nontraditional approaches be incorporated into the teaching practice. This will enable them to contribute to solving one of South Africa’s serious problems.

  11. Energy mix and employment effects

    International Nuclear Information System (INIS)

    Wodopia, F.J.

    2005-01-01

    ''Energy Mix and Employment Effects'' is a subject not to be reduced to the so-called ''job argument''. It also involves the question whether it will be possible to achieve consensus again about the composition of a balanced sustainable energy mix. This term must not be interpreted in a static sense; after all, the framework conditions of energy policy are changing. However, this must not render energy policy unsteady. This requirement should be imposed on economic policy in general, i.e. political interventions, it they are really unavoidable, must be predictable on a long term. This contribution also examines the meaning of the term ''energy mix.'' Aspects of the debate about the climate, especially potential factors influencing the climate, are discussed against the backdrop of scientific validity. Other key points covered are the description and analysis of the energy policy framework. One major aspect under study are all kinds of ''subsidies'' of energy resources and the consequences to the whole economy arising from these financial support mechanisms. The findings are projected onto the employment effects. Finally, the question is raised how to design an energy mix sustainable for the future, and how to achieve it politically and in society. (orig.)

  12. Employability Skills Assessment Tool Development

    Science.gov (United States)

    Rasul, Mohamad Sattar; Rauf, Rose Amnah Abd; Mansor, Azlin Norhaini; Puvanasvaran, A. P.

    2012-01-01

    Research nationally and internationally found that technical graduates are lacking in employability skills. As employability skills are crucial in outcome-based education, the main goal of this research is to develop an Employability Skill Assessment Tool to help students and lecturers produce competent graduates in employability skills needed by…

  13. Welfare Effects of Employment Protection

    NARCIS (Netherlands)

    Belot, M.V.K.; Boone, J.; van Ours, J.C.

    2002-01-01

    Employment protection is often related to costs incurred by the firms when they hire a worker.The stability of the employment relationship, enhanced by employment protection, is also favorable to the productivity of the job.We analyze employment protection focusing on this trade-off between

  14. Fixed term employment

    International Nuclear Information System (INIS)

    Durant, B.W.; Schonberner, M.J.

    1999-01-01

    A series of brief notes were included with this presentation which highlighted certain aspects of contract management. Several petroleum companies have realized the benefits of taking advantage of contract personnel to control fixed G and A, manage the impacts on their organization, contain costs, to manage termination costs, and to fill gaps in lean personnel rosters. An independent contractor was described as being someone who is self employed, often with a variety of work experiences. The tax benefits and flexibility of contractor personnel were also described. Some liability aspects of hiring an independent contractor were also reviewed. The courts have developed the following 4 tests to help determine whether an individual is an employee or an independent contractor: (1) the control test, (2) the business integration test, (3) specific result test, and (4) the economic reality test

  15. Authenticity in Employment Relations

    DEFF Research Database (Denmark)

    Tackney, Charles Thomas

    2018-01-01

    Authenticity is developed and deployed as a criterion variable for a theology of the workplace inquiry that combines theory and methodological development with data analysis. The goal is to show that social science method can offer an empirically valid, prophetic dimension to the study of employm......Authenticity is developed and deployed as a criterion variable for a theology of the workplace inquiry that combines theory and methodological development with data analysis. The goal is to show that social science method can offer an empirically valid, prophetic dimension to the study...... of employment and work parameters in light of religious teachings on the social question at national, organizational, or firm-specific levels. The function of a criterion variable is described, noting that the switch from a dependent variable approach introduces an open-system dynamism to social science...

  16. Kinetics study of hydrochlorothiazide lactose liquid state interaction using conventional isothermal arrhenius method under basic and neutral conditions

    Directory of Open Access Journals (Sweden)

    Faranak Ghaderi

    Full Text Available ABSTRACT The Maillard reaction of hydrochlorothiazide (HCTZ and lactose has been previously demonstrated in pharmaceutical formulations. In this study, the activation energy of - hydrohlorothiazide and lactose interaction in the liquid state was ascertained under basic and neutral conditions. Conventional isothermal High Performance Liquid Chromatography (HPLC technique was employed to ascertain the kinetic parameters using Arrhenius method. Results: The activation energy obtained was 82.43 and 100.28 kJ/mol under basic and neutral conditions, respectively. Consequently, it can be inferred that Maillard reaction is significantly affected by pH, which can be used as a control factor whenever the reaction potentially occurs.

  17. 28 CFR 41.52 - General prohibitions against employment discrimination.

    Science.gov (United States)

    2010-07-01

    ... in employment under any program or activity that receives or benefits from federal financial assistance. (b) A recipient shall make all decisions concerning employment under any program or activity to...) Employer sponsored activities, including social or recreational programs; and (9) Any other term, condition...

  18. Development Aid and Employment

    NARCIS (Netherlands)

    R.E. van der Hoeven (Rolph)

    2012-01-01

    textabstractAbstract. Globalization has led to a precarization of labour, which especially manifests in the unstable working conditions, a lower labour share in national income as well as in a growing income inequality, with the exception of some countries with high initial income inequality.

  19. Chain reaction

    International Nuclear Information System (INIS)

    Balogh, Brian.

    1991-01-01

    Chain Reaction is a work of recent American political history. It seeks to explain how and why America came to depend so heavily on its experts after World War II, how those experts translated that authority into political clout, and why that authority and political discretion declined in the 1970s. The author's research into the internal memoranda of the Atomic Energy Commission substantiates his argument in historical detail. It was not the ravages of American anti-intellectualism, as so many scholars have argued, that brought the experts back down to earth. Rather, their decline can be traced to the very roots of their success after World War II. The need to over-state anticipated results in order to garner public support, incessant professional and bureaucratic specialization, and the sheer proliferation of expertise pushed arcane and insulated debates between experts into public forums at the same time that a broad cross section of political participants found it easier to gain access to their own expertise. These tendencies ultimately undermined the political influence of all experts. (author)

  20. Vinyl Chloride Emulsion Polymerization Reaction: Effect of Various Formulations

    Directory of Open Access Journals (Sweden)

    Seyed Mehrdad Jalilian

    2013-01-01

    Full Text Available A mixture  of  sodium  lauryl  sulfate  (SLS  as  ionic  emulsifer  and  stearyl alcohol as non-ionic emulsifer was employed in a vinyl chloride emulsion polymerization  reaction  to  study  the  infuence  of  various  interactive parameters involved in the reaction system. It was found that the particle size was dependent on the amount and type of emulsifer. The average particle size of polyvinyl chloride was dropped by higher amount of emulsifying agents.  At the gel point, more heat was generated by higher amount of vinyl chloride fed into the reaction system. The molecular weight of the polymer was decreased by increases in reaction temperature while,  it  increased by augmenting  the amount of emulsifer. According to the 13C NMR and FTIR spectroscopic data no defect was detected in the chain structure of synthetic polyvinylchloride product. An optimization of polymerization reaction condition was reached based on ultimate particle size desired for its favorable distribution in plastisols.

  1. Chemistry and reaction kinetics of biowaste torrefaction

    NARCIS (Netherlands)

    Stelt, van der M.J.C.

    2011-01-01

    This thesis addresses the question of how the chemistry and reaction kinetics of torrefaction are influenced by reaction conditions and the effects occuring during the reaction. This research question can be specified by questions such as, what controls their kinetics during torrefaction and what

  2. Pre-employment medical testing in Brazil: ethical challenges.

    Science.gov (United States)

    Palhares, Dario; Laurentino dos Santos, Ivone

    2012-01-01

    Pre-employment medical tests, considered to be a practice within the subspecialty of occupational medicine, are ordered by physicians on behalf of employers. Candidates for a job may be rejected if they are found to suffer from a condition that can be worsened by the job, or one that may put other workers at risk. As the physician who orders pre-employment tests is chosen by the employer, pre-employment tests can violate both the autonomy and the privacy of the individual. This paper discusses ethical conflicts inherent in pre-employment medical testing.

  3. 25 CFR 38.10 - Conditions of employment of educators.

    Science.gov (United States)

    2010-04-01

    ... physical health (handicap), within the parameters of Indian preference. (f) Grievance procedures. The... duly adopted school board policies, including those relating to tribal culture or language. (c...

  4. 76 FR 24575 - General Working Conditions in Shipyard Employment

    Science.gov (United States)

    2011-05-02

    ... other. Examples of isolated locations include an employee working alone on a job task at the far end of... through to perform their job tasks. This may be a vertical, slanted, or horizontal surface, and may... area, such as a fabrication area, machine shop, tank, space, or hold, where one or more employees are...

  5. Womens employment discrimination

    OpenAIRE

    Chernyaeva, V. N.; Черняева, В. Н.

    2014-01-01

    The paper deals with the difficulties faced by women in employment, about stereotypes, that prevent them from getting a decent job and advance their own careers, and the ways to solve this problem. В статье говорится о трудностях, с которыми женщины сталкиваются при трудоустройстве, о стереотипах, которые мешают им получать достойную работу и продвигаться по службе, и о путях решения этой проблемы....

  6. Employment of women in mauritian industry: opportunity or exploitation?

    OpenAIRE

    Hein C

    1981-01-01

    ILO pub-WEP pub. Working paper on industrial sector employment of woman workers in Mauritius - based on interviews and a 1977 survey, examines the conditions (lower minimum wages, higher labour productivity, less absenteeism and easier human relations) dictating employer preference for female industrial workers, discusses motivations, employment by age group, marital status and educational level, job satisfaction and employment policy issues, and includes questionnaire. Bibliography pp. 33 an...

  7. 31 CFR 28.500 - Employment.

    Science.gov (United States)

    2010-07-01

    ... benefits of, or be subjected to discrimination in employment, or recruitment, consideration, or selection... §§ 28.500 through 28.550 apply to: (1) Recruitment, advertising, and the process of application for...-sponsored activities, including social or recreational programs; and (10) Any other term, condition, or...

  8. 15 CFR 8a.500 - Employment.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Employment. 8a.500 Section 8a.500 Commerce and Foreign Trade Office of the Secretary of Commerce NONDISCRIMINATION ON THE BASIS OF SEX IN...-sponsored activities, including social or recreational programs; and (10) Any other term, condition, or...

  9. Incidents of chemical reactions in cell equipment

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, N.M.; Barlow, C.R. [Uranium Enrichment Organization, Oak Ridge, TN (United States)

    1991-12-31

    Strongly exothermic reactions can occur between equipment structural components and process gases under certain accident conditions in the diffusion enrichment cascades. This paper describes the conditions required for initiation of these reactions, and describes the range of such reactions experienced over nearly 50 years of equipment operation in the US uranium enrichment program. Factors are cited which can promote or limit the destructive extent of these reactions, and process operations are described which are designed to control the reactions to minimize equipment damage, downtime, and the possibility of material releases.

  10. Monitoring mass transport in heterogeneously catalyzed reactions by field-gradient NMR for assessing reaction efficiency in a single pellet

    Science.gov (United States)

    Buljubasich, L.; Blümich, B.; Stapf, S.

    2011-09-01

    An important aspect in assessing the performance of a catalytically active reactor is the accessibility of the reactive sites inside the individual pellets, and the mass transfer of reactants and products to and from these sites. Optimal design often requires a suitable combination of micro- and macropores in order to facilitate mass transport inside the pellet. In an exothermic reaction, fluid exchange between the pellet and the surrounding medium is enhanced by convection, and often by the occurrence of gas bubbles. Determining mass flow in the vicinity of a pellet thus represents a parameter for quantifying the reaction efficiency and its dependence on time or external reaction conditions. Field gradient Nuclear Magnetic Resonance (NMR) methods are suggested as a tool for providing parameters sensitive to this mass flow in a contact-free and non-invasive way. For the example of bubble-forming hydrogen peroxide decomposition in an alumina pellet, the dependence of the mean-squared displacement of fluid molecules on spatial direction, observation time and reaction time is presented, and multi-pulse techniques are employed in order to separate molecular displacements from coherent and incoherent motion on the timescale of the experiment. The reaction progress is followed until the complete decomposition of H 2O 2.

  11. Temporary Employment and Perceived Employability: Mediation by Impression Management

    Science.gov (United States)

    De Cuyper, Nele; De Witte, Hans

    2010-01-01

    Perceived employability (PE) has been advanced as the upcoming resource for career development, particularly for temporary workers. The question is how temporary workers become employable. Our hypothesis is that temporary workers more than permanent workers use impression management to become employable, both on the internal and the external labor…

  12. A Conceptual Understanding of Employability: The Employers' View in Rwanda

    Science.gov (United States)

    Bamwesiga, Penelope Mbabazi

    2013-01-01

    Many governments believe that investing in human capital should increase citizens' employability, which is why it is often presented as a solution to the problems of knowledge-based economies and societies, rising unemployment rates and economic competiveness. The aim of this study is to understand employers' views regarding the employability of…

  13. One- and two-dimensional chemical exchange nuclear magnetic resonance studies of the creatine kinase catalyzed reaction

    International Nuclear Information System (INIS)

    Gober, J.R.

    1988-01-01

    The equilibrium chemical exchange dynamics of the creatine kinase enzyme system were studied by one- and two-dimensional 31 P NMR techniques. Pseudo-first-order reaction rate constants were measured by the saturation transfer method under an array of experimental conditions of pH and temperature. Quantitative one-dimensional spectra were collected under the same conditions in order to calculate the forward and reverse reaction rates, the K eq , the hydrogen ion stoichiometry, and the standard thermodynamic functions. The pure absorption mode in four quadrant two-dimensional chemical exchange experiment was employed so that the complete kinetic matrix showing all of the chemical exchange process could be realized

  14. Reação de linhagens de feijoeiro ao fungo Fusarium oxysporum f. sp. phaseoli em condições controladas Reaction of common bean lines to Fusarium oxysporum f. sp. phaseoli in controlled conditions

    Directory of Open Access Journals (Sweden)

    Mônica Juliani Zavaglia Pereira

    2011-10-01

    Full Text Available Entre os patógenos que mais contribuem para a redução da produtividade do feijoeiro no Brasil está o Fusarium oxysporum f. sp. phaseoli. O emprego de cultivares resistentes é o controle mais eficaz para esse patógeno. Conduziu-se este trabalho, com o objetivo de avaliar linhagens de feijoeiro (Phaseolus vulgaris L. do banco de germoplasma da Universidade Federal de Lavras (UFLA, quanto a reação ao Fusarium oxysporum f. sp. phaseoli e, ao mesmo tempo, estimar os parâmetros genéticos e fenotípicos que possam auxiliar em futuros programas de melhoramento para esse caráter. Foram avaliadas 367 linhagens em dez experimentos. As testemunhas 'Carioca' (suscetível e 'Carioca MG' (resistente foram utilizadas em todos os experimentos. O delineamento utilizado foi inteiramente ao acaso, com cinco repetições e parcelas de uma planta por vaso. As inoculações foram realizadas segundo a metodologia de corte e imersão de raízes na suspensão de esporos do fungo e as avaliações realizadas aos 21 dias após a inoculação com base no índice de severidade da doença empregando-se notas de 1 (plantas sem sintomas a 9 (plantas mortas.Das linhagens do banco de germoplasma da Universidade Federal de Lavras (UFLA avaliadas, 36,5% foram resistentes ao Fusarium oxysporum f. sp. phaseoli. Entre as resistentes, a maioria foi linhagens obtidas antes de 1990. Das 18 linhagens dos experimentos de VCU, do período de 2005/06, apenas quatro foram suscetíveis. A estimativa da herdabilidade (h² foi elevada (h² = 87%, indicando que, a princípio, o caráter é de fácil seleção.Among the pathogens that most contribute for reducing the productivity of beans in Brazil is the Fusarium oxysporum f. sp. phaseoli. The use of resistant cultivars is the most effective control for this pathogen. The aim of this study was to evaluate germoplasm bean (Phaseolus vulgaris L. lines of the Federal University of Lavras (UFLA as the reaction to the Fusarium oxysporum f

  15. Endoscopy and homogeneous-heterogeneous reactions in MHD radiative peristaltic activity of Ree-Eyring fluid

    Science.gov (United States)

    Hayat, Tasawar; Akram, Javaria; Alsaedi, Ahmed; Zahir, Hina

    2018-03-01

    Endoscopic and homogeneous-heterogeneous reactions in MHD peristalsis of Ree-Eyring fluid are addressed. Mathematical modeling and analysis have been performed by utilizing cylindrical coordinates. Nonlinear thermal radiation is present. Impact of slip boundary conditions on temperature and velocity on outer tube are taken into consideration. Lubrication approach is employed. The nonlinear system is executed numerically for solutions of velocity, temperature and concentration. Graphical results are obtained to predict physical interpretation of various embedded parameters. It is noted that homogeneous and heterogeneous reactions affect the concentration alternatively. Moreover Brinkman number rises the temperature and heat transfer coefficient whereas thermal slip drops temperature and heat transfer rate.

  16. Extension of a Kinetic-Theory Approach for Computing Chemical-Reaction Rates to Reactions with Charged Particles

    Science.gov (United States)

    Liechty, Derek S.; Lewis, Mark J.

    2010-01-01

    Recently introduced molecular-level chemistry models that predict equilibrium and nonequilibrium reaction rates using only kinetic theory and fundamental molecular properties (i.e., no macroscopic reaction rate information) are extended to include reactions involving charged particles and electronic energy levels. The proposed extensions include ionization reactions, exothermic associative ionization reactions, endothermic and exothermic charge exchange reactions, and other exchange reactions involving ionized species. The extensions are shown to agree favorably with the measured Arrhenius rates for near-equilibrium conditions.

  17. Single-employer Pension Plans

    Data.gov (United States)

    Pension Benefit Guaranty Corporation — This spreadsheet lists the active single-employer pensions plans insured by PBGC. Plans are identified by name, employer identification number (EIN) and plan number...

  18. Employment challenges in the future

    DEFF Research Database (Denmark)

    2011-01-01

    Discussion of challenges in employment challenges in Europe and a brief discription of the Danish flexicurity system......Discussion of challenges in employment challenges in Europe and a brief discription of the Danish flexicurity system...

  19. Catalytic Organometallic Reactions of Ammonia

    Science.gov (United States)

    Klinkenberg, Jessica L.

    2012-01-01

    Until recently, ammonia had rarely succumbed to catalytic transformations with homogeneous catalysts, and the development of such reactions that are selective for the formation of single products under mild conditions has encountered numerous challenges. However, recently developed catalysts have allowed several classes of reactions to create products with nitrogen-containing functional groups from ammonia. These reactions include hydroaminomethylation, reductive amination, alkylation, allylic substitution, hydroamination, and cross-coupling. This Minireview describes examples of these processes and the factors that control catalyst activity and selectivity. PMID:20857466

  20. Basic reactions induced by radiation

    International Nuclear Information System (INIS)

    Charlesby, A.

    1980-01-01

    This paper summarises some of the basic reactions resulting from exposure to high energy radiation. In the initial stages energy is absorbed, but not necessarily at random, giving radical and ion species which may then react to promote the final chemical change. However, it is possible to intervene at intermediate stages to modify or reduce the radiation effect. Under certain conditions enhanced reactions are also possible. Several expressions are given to calculate radiation yield in terms of energy absorbed. Some analogies between radiation-induced reactions in polymers, and those studied in radiobiology are outlined. (author)