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Sample records for catalyst development possibilities

  1. Strategies for catalyst development: possibilities of the ``rational approach`` illustrated with partial oxidation reactions

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, W.; Schedel-Niedrig, T.; Schloegl, R. [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin (Germany). Abt. Oberflaechenphysik

    1998-12-31

    The paper discusses two petrochemical selective oxidation reactions namely the practised formation of styrene (STY) and the desired oxidative functionalisation of propane. The present knowledge about the mode of operation of oxide catalysts is critically considered. The dehydrogenation of ethylbenzene (EB) should be described by an oxidehydration with water acting as oxidant. The potential role of the coke formed during catalytic reaction as co-catalyst will be discussed. Selective oxidation is connected with the participation of lattice oxygen mechanism which transforms unselective gas phase oxygen into selective oxygen. The atomistic description of this process is still quite unclear as well as the electron structural properties of the activated oxygen atom. The Role of solid state acidity as compared to the role of lattice oxygen is much less well investigated modern multiphase-multielement oxide (MMO) catalysts. The rationale is that the significant efforts made to improve current MMO systems by chemical modifications can be very much more fruitful when in a first step the mode of action of a catalyst is clarified on the basis of suitable experiments. Such time-consuming experiments at the beginning of a campaign for catalyst improvement pay back their investment in later stages of the project when strategies of chemical development can be derived on grounds of understanding. (orig.)

  2. Development of GREET Catalyst Module

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhichao [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Dunn, Jennifer B. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Cronauer, Donald C. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division

    2014-09-01

    Catalysts are critical inputs for many pathways that convert biomass into biofuels. Energy consumption and greenhouse gas (GHG) emissions during the production of catalysts and chemical inputs influence the life-cycle energy consumption, and GHG emissions of biofuels and need to be considered in biofuel life-cycle analysis (LCA). In this report, we develop energy and material flows for the production of three different catalysts (tar reforming, alcohol synthesis, Zeolite Socony Mobil-5 [ZSM-5]) and two chemicals (olivine, dimethyl ether of polyethylene glycol [DEPG]). These compounds and catalysts are now included in the Greenhouse Gases, Regulated Emissions and Energy Use in Transportation (GREET™) catalyst module. They were selected because they are consumed in existing U.S. Department of Energy (DOE) analyses of biofuel processes. For example, a thermochemical ethanol production pathway (indirect gasification and mixed alcohol synthesis) developed by the National Renewable Energy Laboratory (NREL) uses olivine, DEPG, and tar reforming and alcohol synthesis catalysts (Dutta et al., 2011). ZSM-5 can be used in biofuel production pathways such as catalytic upgrading of sugars into hydrocarbons (Biddy and Jones, 2013). Other uses for these compounds and catalysts are certainly possible. In this report, we document the data sources and methodology we used to develop material and energy flows for the catalysts and compounds in the GREET catalyst module. In Section 2 we focus on compounds used in the model Dutta et al. (2011) developed. In Section 3, we report material and energy flows associated with ZSM-5 production. Finally, in Section 4, we report results.

  3. Development of GREET Catalyst Module

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhichao [Argonne National Lab. (ANL), Argonne, IL (United States); Benavides, Pahola T. [Argonne National Lab. (ANL), Argonne, IL (United States); Dunn, Jennifer B. [Argonne National Lab. (ANL), Argonne, IL (United States); Cronauer, Donald C. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-09-01

    In this report, we develop energy and material flows for the production of five different catalysts (tar reforming, alcohol synthesis, Zeolite Socony Mobil-5 [ZSM-5], Mo/Co/ γ-Al2O3, and Pt/ γ-Al2O3) and two chemicals (olivine, dimethyl ether of polyethylene glycol [DEPG]). These compounds and catalysts are now included in the Greenhouse Gases, Regulated Emissions and Energy Use in Transportation (GREET™) catalyst module.

  4. NEW REFORMING CATALYST DEVELOPED BY RIPP

    Institute of Scientific and Technical Information of China (English)

    PUZhong-ying

    2003-01-01

    To meet the demands for high-octane gasoline and aromatics,catalytic reforming process has been advancing quickly in China.The reforming catalysts developed by RIPP have been used in more than 80% capacity of domestic CCR and SR units.This paper introduces the properties of PSVI CCR catalyst developed by RIPP in recent years and also the result from commercial units.The PS-VI catalyst has high activity and good selectivity,under the same reaction conditions,the carbon on catalyst was lowered by 26% in mass as compared with that of the reference catalyst.Among the SR reforming catalysts,the new type of PRT series catalysts have excellent performance at low reaction pressure compared with the ref.Cat A.The aromatics and reformate mass yields of PRT catalyst were 2%-3% and 3%,respectively ,higher than those of Cat A,and the run length was 30%-40% longer as well,which exhibits good prospect of application.

  5. Recent developments on ultrasound assisted catalyst-free organic synthesis.

    Science.gov (United States)

    Banerjee, Bubun

    2017-03-01

    Mother Nature needs to be protected from ever increasing chemical pollutions associated with synthetic organic processes. The fundamental challenge for today's methodologists is to make their protocols more environmentally benign and sustainable by avoiding the extensive use of hazardous reagents and solvents, harsh reaction conditions, and toxic metal catalysts. However, the people of the twenty-first century are well aware about the side effects of those hazardous substances used and generated by the chemical processes. As a result, the last decade has seen a tremendous outburst in modifying chemical processes to make them 'sustainable' for the betterment of our environment. Catalysts play a crucial role in organic synthesis and thus they find huge applications and uses. Scientists' continuously trying to modify the catalysts to reduce their toxicity level, but the most benign way is to design an organic reaction without catalyst(s), if possible. It is worthy to mention that the involvement of ultrasound in organic synthesis is sometimes fulfilling this goal. In many occasions the applications of ultrasound can avoid the use of catalysts in organic reactions. Such beneficial features as a whole have motivated the organic chemists to apply ultrasonic irradiation in more heights and as a results, in recent past, there were immense applications of ultrasound in organic reactions for the synthesis of diverse organic scaffolds under catalyst-free condition. The present review summarizes the latest developments on ultrasound assisted catalyst-free organic synthesis reported so far.

  6. FY 1997 report on the development of excellent catalysts for creation of new industries. New frontier catalyst 21; 1997 nendo chosa hokokusho (shinsangyo sosei no tame no excellence catalyst no kaihatsu). New frontier catalyst 21

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    Survey was made for establishment of an effective fast search technique of practical catalysts. Catalyst technology is an important basic technology for industrial fields such as energy and environment fields. In many cases, catalysts have been developed by trial and error consuming a long time and huge research cost. Study was made on efficient analysis and measurement techniques, and systematic production technique of advanced catalysts based on these techniques. This survey was effective in finding a guidance for improving catalysts used in the previous processes, and facilitating searches for fields previously slow in development of catalysts. Advanced catalysts possible to actively selectively produce target products under high pressure/temperature conditions are much in demand. Recently in-situ analysis technology for observing molecules and material surfaces under ultrahigh-pressure/temperature conditions has been studied. Observational study was made on catalytic behavior under catalytic reaction condition using partial oxidation, selective hydrogenation and isomerization as model reactions. 111 refs., 103 figs., 9 tabs.

  7. Possibility of Wastewater Treatment Using MFC with Ni-Co Catalyst of Fuel Electrode

    Directory of Open Access Journals (Sweden)

    Włodarczyk Paweł P.

    2016-06-01

    Full Text Available One of the problems with microbial fuel cells is a low current density of those energy sources. Nonetheless, it is possible to increase the current density by using the catalyst for fuel electrode (anode - as long as a low cost catalyst can be found. The possibility of wastewater treatment using the Ni-Co alloy as catalyst for MFC’s is presented in this paper. The alloys were obtained with different concentrations of Co (15 and 50% of Co. The increase of current density with Ni-Co catalyst is approximately 0,1 mA/cm2. So, a fundamental possibility wastewater treatment using the Ni-Co alloy as catalyst for microbial fuel cells was presented.

  8. Possibility of Wastewater Treatment Using MFC with Ni-Co Catalyst of Fuel Electrode

    Science.gov (United States)

    Włodarczyk, Paweł P.; Włodarczyk, Barbara

    2016-06-01

    One of the problems with microbial fuel cells is a low current density of those energy sources. Nonetheless, it is possible to increase the current density by using the catalyst for fuel electrode (anode) - as long as a low cost catalyst can be found. The possibility of wastewater treatment using the Ni-Co alloy as catalyst for MFC's is presented in this paper. The alloys were obtained with different concentrations of Co (15 and 50% of Co). The increase of current density with Ni-Co catalyst is approximately 0,1 mA/cm2. So, a fundamental possibility wastewater treatment using the Ni-Co alloy as catalyst for microbial fuel cells was presented.

  9. Development and Commercial Application of Third Generation Resid Hydrotreating Catalysts

    Institute of Scientific and Technical Information of China (English)

    Hu Dawei; Yang Qinghe; Dai Lishun; Zhao Xinqiang

    2013-01-01

    Based on the mechanism of resid hydrotreating reaction by coordinating the catalyst activity and stability, the diffusion mechanism and catalyst reactivity, the cost and catalyst performance, and the production and application re-quirements, the third-generation series catalysts for residue hydrotreating have been developed by Research Institute of Petroleum Processing, SINOPEC. The new series RHT catalysts possess higher activity for HDS, HDM and HDCCR per-formance as well as longer run length. The commercial results for application of these catalysts have demonstrated that the new catalyst system performs better than the reference ones.

  10. Fuel cell development for transportation: Catalyst development

    Energy Technology Data Exchange (ETDEWEB)

    Doddapaneni, N. [Sandia National Lab., Albuquerque, NM (United States)

    1996-04-01

    Fuel cells are being considered as alternate power sources for transportation and stationary applications. With proton exchange membrane (PEM) fuel cells the fuel crossover to cathodes causes severe thermal management and cell voltage drop due to oxidation of fuel at the platinized cathodes. The main goal of this project was to design, synthesize, and evaluate stable and inexpensive transition metal macrocyclic catalysts for the reduction of oxygen and be electrochemically inert towards anode fuels such as hydrogen and methanol.

  11. Development of radioactive platinum group metal catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Chung, H.S.; Kim, Y.S.; Kim, Y.E. [and others

    1999-03-01

    The fission product nuclides generated during the irradiation of reactor fuel include many useful elements, among them platinum group metals such as ruthenium, rhodium and palladium which are of great industrial importance, occur rarely in nature and are highly valuable. In this research, the authors reviewed various PGM recovery methods. Recovery of palladium from seven-component simulated waste solutions was conducted by selective precipitation method. The recovery yield was more than 99.5% and the purity of the product was more than 99%. Wet-proof catalyst was prepared with the recovered palladium. The specific surface area of the catalyst support was more than 400m{sup 2}/g.The content of palladium impregnated on the support was 1 to 10 wt. %. Hydrogen isotope exchange efficiency of more than 93% to equilibrium with small amount of the catalyst was obtained. It was turned out possible to consider using such palladium or other very low active PGM materials in applications where its activity is unimportant as in nuclear industries. (author). 86 refs., 44 tabs., 88 figs.

  12. Advanced Aqueous Phase Catalyst Development using Combinatorial Methods Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The use of combinatorial methods is proposed to rapidly screen catalyst formulations for the advanced development of aqueous phase oxidation catalysts with greater...

  13. Development and Application of CDOS Series Catalysts for Bottoms Cracking

    Institute of Scientific and Technical Information of China (English)

    Wang Mingjin; Xu Mingde; Zhu Yuxia

    2013-01-01

    Development of CDOS catalyst for bottoms cracking is based on DOSY zeolite, which is characterized by high metal tolerance. The results of DOSY tests have shown that the catalyst has better activity retention at high metal content in the feed. The performance of catalyst tested in the bench scale was superior over that of the reference catalyst. The results of catalyst application have shown that the CDOS series catalysts have better bottoms cracking activity, high metal tolerance, excellent dry gas selectivity, and enhanced liquid yield.

  14. Advanced Aqueous Phase Catalyst Development using Combinatorial Methods Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Combinatorial methods are proposed to develop advanced Aqueous Oxidation Catalysts (AOCs) with the capability to mineralize organic contaminants present in effluents...

  15. Development of a Catalyst/Sorbent for Methane Reforming

    Energy Technology Data Exchange (ETDEWEB)

    B.H. Shans; T.D. Wheelock; Justinus Satrio; Karl Albrecht; Tanya Harris Janine Keeley; Ben Silva; Aaron Shell; Molly Lohry; Zachary Beversdorf

    2008-12-31

    This project led to the further development of a combined catalyst and sorbent for improving the process technology required for converting CH{sub 4} and/or CO into H{sub 2} while simultaneously separating the CO{sub 2} byproduct all in a single step. The new material is in the form of core-in-shell pellets such that each pellet consists of a CaO core surrounded by an alumina-based shell capable of supporting a Ni catalyst. The Ni is capable of catalyzing the reactions of steam with CH{sub 4} or CO to produce H{sub 2} and CO{sub 2}, whereas the CaO is capable of absorbing the CO{sub 2} as it is produced. The absorption of CO{sub 2} eliminates the reaction inhibiting effects of CO{sub 2} and provides a means for recovering the CO{sub 2} in a useful form. The present work showed that the lifecycle performance of the sorbent can be improved either by incorporating a specific amount of MgO in the material or by calcining CaO derived from limestone at 1100 C for an extended period. It also showed how to prepare a strong shell material with a large surface area required for supporting an active Ni catalyst. The method combines graded particles of {alpha}-alumina with noncrystalline alumina having a large specific surface area together with a strength promoting additive followed by controlled calcination. Two different additives produced good results: 3 {micro}m limestone and lanthanum nitrate which were converted to their respective oxides upon calcination. The oxides partially reacted with the alumina to form aluminates which probably accounted for the strength enhancing properties of the additives. The use of lanthanum made it possible to calcine the shell material at a lower temperature, which was less detrimental to the surface area, but still capable of producing a strong shell. Core-in-shell pellets made with the improved shell materials and impregnated with a Ni catalyst were used for steam reforming CH{sub 4} at different temperatures and pressures. Under all

  16. Development of high performance vinyl acetate monomer (VAM) catalysts

    OpenAIRE

    2009-01-01

    The focus of this study was to develop high performance catalysts for the synthesis of vinyl acetate monomer (VAM). By systematic variation of different preparation parameters a multitude of shell catalysts consisting of PdAu nanoparticles supported on a bentonite carrier was explored. In order to investigate the influence of these alterations on catalytic performance, a catalyst classification was accomplished in a high-throughput Temkin test unit by comparison with a highly efficient commer...

  17. TECHNOLOGY DEVELOPMENT FOR IRON FISCHER-TROPSCH CATALYSTS

    Energy Technology Data Exchange (ETDEWEB)

    Davis, B.H.

    1998-07-22

    The goal of the proposed work described in this Final Report was the development of iron-based Fischer-Tropsch catalysts that combined high activity, selectivity and life with physical robustness for slurry phase reactors that will produce either low-alpha or high-alpha products. The work described here has optimized the catalyst composition and pretreatment operation for a low-alpha catalyst. In parallel, work has been conducted to design a high-alpha iron catalyst that is suitable for slurry phase synthesis. Studies have been conducted to define the chemical phases present at various stages of the pretreatment and synthesis stages and to define the course of these changes. The oxidation/reduction cycles that are anticipated to occur in large, commercial reactors have been studied at the laboratory scale. Catalyst performance has been determined for catalysts synthesized in this program for activity, selectivity and aging characteristics.

  18. Developments of Catalysts for Hydrogen Production from Dimethyl Ether

    Institute of Scientific and Technical Information of China (English)

    Kaoru; Takeishi

    2007-01-01

    1 Results Dimethyl ether (DME) is expected as a clean fuel of the 21st century.I have developed new catalysts for hydrogen production by steam reforming of DME.Cu-Zn/Al2O3 catalysts prepared by the sol-gel method produce large quantities of H2 and CO2 by DME steam reforming under lower reaction temperature[1].However,the sol-gel catalysts will be more expensive than general catalysts prepared by impregnation methods and coprecipitation methods,because the precursor,alkoxides are very expensive.For pract...

  19. Bioplastics: Development, Possibilities and Difficulties

    Directory of Open Access Journals (Sweden)

    Aistė Karpušenkaitė

    2014-07-01

    Full Text Available New possible ways of plastics manufacture and waste treatment are being searched when trying to tackle the problems related to the growth of waste quantities and decline in non-renewable resources. Presently, the most promising and effective way to solve the mentioned problems is production of bioplastics, but its way to recognition is very slow. One of the barriers is the absence of clear and united opinion throughout the EU Arising new discussions about biodegradable and biobased plastics will allow responsible authorities to update and adapt the legal law, which now almost does not include any reglement on bioplastics production and usage. The other issues of bioplastics are social aspects as this material can be made of primal food sources like crops, and the ecological ones because of their unknown effects on human health and the environment. Nevertheless, the main problem remains the same - the price of petro-plastics is still lower than that of bioplastics. Despite this, the biggest companies of the world are starting an initiative to manufacture this new kind of plastics and to widen the range of bioplastics usage in packaging. Considering today’s situation and tendencies, at the end of this paper the recommendations for the improvement and speeding up of the processes related to bioplastics manufacture, usage and its waste management in Europe and Lithuania are presented. DOI: http://dx.doi.org/10.5755/j01.erem.68.2.6777

  20. The development of precipitated iron catalysts with improved stability; Final report, September 1987--September 1992

    Energy Technology Data Exchange (ETDEWEB)

    Abrevaya, H.

    1993-12-27

    Precipitated iron catalysts are expected to be used in next generation slurry reactors for large-scale production of transportation fuels from synthesis gas. These reactors are expected to operate at higher temperatures and lower H{sub 2}:CO ratios relative to the Sasol Arge reactor (Table 1A). The feasibility of using iron catalysts has been demonstrated under relatively mild Arge-type conditions but not under more severe slurry conditions. Possibly, an improvement in catalytic stability will be needed to make iron catalysts suitable for slurry operation. This program was aimed at identifying the chemical principles governing the deactivation of precipitated iron catalysts during Fischer-Tropsch synthesis and use of these chemical principles in the design of more stable catalysts. A new precipitated Fe catalyst was developed in this program for slurry reactor operation. The new Fe catalyst is predicted to perform slightly below the performance targets for slurry bubble column operation. Stability targets appear to be achievable. This catalyst did not noticeably deactivate during 1,740 hours on-stream. Compared to the selectivity target, an excess of 2% C{sub 1} + C{sub 2} was formed at 265{degrees}C. Based on the initial catalyst inventory in the autoclave, the catalyst seems to be short of the activity target by a factor of 1.8 at 265{degrees}C and 1.3 at 275{degrees}C. However, actual specific activities are likely to be closer to target because of catalyst inventory loss across the filter during the run and because catalytic activities were underestimated at low conversions.

  1. POISON RESISTANT CATALYST DEVELOPMENT AND TESTING

    Energy Technology Data Exchange (ETDEWEB)

    Andrew W. Wang

    2001-03-29

    The Alternative Fuels Field Test Unit (AFFTU) is a portable laboratory designed specifically to provide on-site evaluation of potential feedstocks for processes that produce alternative fuels from indigenous raw materials such as coal, natural gas or environmentally disadvantaged carbonaceous feedstocks. Since conversion of these raw materials into feed gas streams can produce a variety of bulk gas compositions, which furthermore can contain a myriad of trace components, it is necessary to evaluate each new feedstock on an individual basis. While it is possible to prepare blended gas mixtures to simulate the bulk composition of a known feedstock, it is neither possible nor cost-effective to simulate adequately the variety of trace chemicals present in that feedstock--some of which may not even be detected by routine analysis. Additionally, the transient composition of the gas during upsets or routine process changes may have an impact on the proposed process that is not foreseen in standard design. To address these concerns, the AFFTU was constructed with the following experimental capabilities: (1) A state-of-the-art gas chromatograph system to perform semi-continuous monitoring of both bulk composition and the concentration of key trace poisons down to one part per billion (ppb). (2) A 30-mL reactor system that can accept up to two feed streams from the customer, allowing a true life test with the actual gas projected for use in the proposed facility. (3) A manifold of four adsorbent beds, located upstream of the reactor, which permits the testing of adsorbents for the removal of contaminants from the feed stream. The effectiveness of these adsorbents may be evaluated either by analysis of the gas upstream and downstream of the bed (or at an intermediate point within the bed) or by observing the impact of the presence or absence of that bed on the actual stability of the catalyst activity. To achieve portability, the AFFTU was constructed in a commercial 48-foot

  2. Technology development for iron Fischer-Tropsch catalysts

    Energy Technology Data Exchange (ETDEWEB)

    O`Brien, R.J.; Raje, A.; Keogh, R.A. [and others

    1995-12-31

    The objective of this research project is to develop the technology for the production of physically robust iron-based Fischer-Tropsch catalysts that have suitable activity, selectivity and stability to be used in the slurry phase synthesis reactor development. The catalysts that are developed shall be suitable for testing in the Advanced Fuels Development Facility at LaPorte, Texas, to produce either low-or high-alpha product distributions. Previous work by the offeror has produced a catalyst formulation that is 1.5 times as active as the {open_quotes}standard-catalyst{close_quotes} developed by German workers for slurry phase synthesis. In parallel, work will be conducted to design a high-alpha iron catalyst this is suitable for slurry phase synthesis. Studies will be conducted to define the chemical phases present at various stages of the pretreatment and synthesis stages and to define the course of these changes. The oxidation/reduction cycles that are anticipated to occur in large, commercial reactors will be studied at the laboratory scale. Catalyst performance will be determined for catalysts synthesized in this program for activity, selectivity and aging characteristics.

  3. Development and Commercial Application of DZC Ⅱ-1 Type Catalyst for Hydrogenation of Pyrolysis Gasoline

    Institute of Scientific and Technical Information of China (English)

    Zhao Ye; Wang Fucun

    2006-01-01

    Commercial application of the DZC Ⅱ-1 catalyst developed on the basis of the DZ-1 catalyst was introduced. The application tests of the catalyst under overload had proved that this catalyst demon-strated satisfactory adaptability to feedstock after continued operation for 20 months with little changes in the bed pressure drop, the reactor inlet temperature and the bed temperature rise. The DZC Ⅱ-1 catalyst was regarded as the best catalyst for the second-stage hydrogenation of pyrolysis gasoline.

  4. (Invited) Towards the Development of Active, Stable and Abundant Catalysts for Oxygen Evolution in Acid

    DEFF Research Database (Denmark)

    Stephens, Ifan; Paoli, Elisa Antares; Frydendal, Rasmus

    2015-01-01

    . Should this activity be stabilised for instance, by utilising a more stable oxide such as TiOx or IrOx,(6, 7) PEM electrolysis could indeed be scalable to the TW level. Alternatively, the precious metal catalysts could be eliminated altogether and replaced by abundant, active and stable catalysts......Ox does indeed engender MnOx with modest stability. Further development of this strategy opens up the possibility of developing active, stable and abundant non-precious metal oxides for oxygen evolution in acid. References 1. M. K. Debe, S. M. Hendricks, G. D. Vernstrom, M. Meyers, M. Brostrom, M...

  5. In-situ characterization of heterogeneous catalysts

    CERN Document Server

    Rodriguez, Jose A; Chupas, Peter J

    2013-01-01

    Helps researchers develop new catalysts for sustainable fuel and chemical production Reviewing the latest developments in the field, this book explores the in-situ characterization of heterogeneous catalysts, enabling readers to take full advantage of the sophisticated techniques used to study heterogeneous catalysts and reaction mechanisms. In using these techniques, readers can learn to improve the selectivity and the performance of catalysts and how to prepare catalysts as efficiently as possible, with minimum waste. In-situ Characterization of Heterogeneous Catalysts feat

  6. An Overview of Recent Development in Composite Catalysts from Porous Materials for Various Reactions and Processes

    Directory of Open Access Journals (Sweden)

    Zaiku Xie

    2010-05-01

    Full Text Available Catalysts are important to the chemical industry and environmental remediation due to their effective conversion of one chemical into another. Among them, composite catalysts have attracted continuous attention during the past decades. Nowadays, composite catalysts are being used more and more to meet the practical catalytic performance requirements in the chemical industry of high activity, high selectivity and good stability. In this paper, we reviewed our recent work on development of composite catalysts, mainly focusing on the composite catalysts obtained from porous materials such as zeolites, mesoporous materials, carbon nanotubes (CNT, etc. Six types of porous composite catalysts are discussed, including amorphous oxide modified zeolite composite catalysts, zeolite composites prepared by co-crystallization or overgrowth, hierarchical porous catalysts, host-guest porous composites, inorganic and organic mesoporous composite catalysts, and polymer/CNT composite catalysts.

  7. Development of novel catalysts for the photocatalytic hydrogen formation

    Energy Technology Data Exchange (ETDEWEB)

    Pilz, Thomas David

    2011-11-16

    For future conversion of sunlight into chemical energy, intramolecular systems for artifical photosynthesis were developed in several stages. This comprised the fabrication of novel ligands and the resulting charge transfer chromophores (Ru(bpy)3-type) and/or catalytically active complexes (Pt, Pd). These were combined into heteronuclear diades consisting of covalently bonded functional subunits. In particular, the chromophores and catalysis centers were bridged so that their individual properties were retained while their individual functions were combined into a supramolecular photocatalyst. This makes it possible to reduce protons to hydrogen on these catalysts when exposed to light. As bridging units, oligodentate ligands were produced and used that can coordinate the active metal centers via bipyridines and N-heterocyclic carbenes (NHC). A number of such heterobimetal complexes, their initial compounds and appropriate reference compounds were produced, characterized, and compared. Apart from structural, photophysical and electrochemical analyses, also successful catalysis experiment were carried out with the manufactured photocatalysts for light-induced hydrogen production from water. Further representative control experiments and dynamic light scattering analyses were carried out in order to gain deeper understanding of the processes going on during catalysis. By comparing the properties of the fabricated catalysts with selected reference compounds, information was obtained on the structure-property relationships of the systems. (orig.) [German] Fuer die zukuenftige Umwandlung von Sonnenlicht in chemische Energie wurden schrittweise intramolekular arbeitende Systeme fuer eine artifizielle Photosynthese aufgebaut. Dabei wurde eine Anzahl von neuen Liganden und den resultierenden Charge-Transfer-Chromophoren (Ru(bpy)3-artig) bzw. katalyseaktiven Komplexen (Pt, Pd) hergestellt. Diese wurden zu heteronuklearen Diaden zusammengefuegt, welche aus kovalent

  8. Development of industrial catalysts for sustainable chlorine production.

    Science.gov (United States)

    Mondelli, Cecilia; Amrute, Amol P; Moser, Maximilian; Schmidt, Timm; Pérez-Ramírez, Javier

    2012-01-01

    The heterogeneously catalyzed gas-phase oxidation of HCl to Cl(2) offers an energy-efficient and eco- friendly route to recover chlorine from HCl-containing byproduct streams in the chemical industry. This process has attracted renewed interest in the last decade due to an increased chlorine demand and the growing excess of byproduct HCl from chlorination processes. Since its introduction (by Deacon in 1868) and till recent times, the industrialization of this reaction has been hindered by the lack of sufficiently active and durable materials. Recently, RuO(2)-based catalysts with outstanding activity and stability have been designed and they are being implemented for large-scale Cl(2) recycling. Herein, we review the main limiting features of traditional Cu-based catalysts and survey the key steps in the development of the new generation of industrial RuO(2)-based materials. As the expansion of this technology would benefit from cheaper, but comparably robust, alternatives to RuO(2)-based catalysts, a nov el CeO(2)-based catalyst which offers promising perspectives for application in this field has been introduced.

  9. ECONOMIC FREEDOM – A CATALYST FOR DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Rozalia Iuliana KICSI

    2014-12-01

    Full Text Available Liberal doctrine, in its various attempts to find legitimacy, has exerted a real influence on the ”architecture” of the world economy. Liberal rhetoric, validated by historical reality, has shown that liberalism, through its virtues, design a proper environment for both individuals and nations development. In this equation of development the catalytic role of economic freedom and free trade was a theme of reflections during the evolution of many nations, but emphasis on the quantitative dimensions was obvious. In the last decades, attention has been focused on the quality of development too, understanding that the wealth of a nation is reflected not only in the improvement of macroeconomic indicators, but in the better quality of individuals’ life.

  10. Thermal desalination in GCC and possible development

    KAUST Repository

    Darwish, Mohamed Ali

    2013-06-28

    The Water Desalination and Reuse Center in King Abdulla University of Science and Technology, in Saudi Arabia, held a workshop on thermal desalination on the 11th and 12th of March, 2013. This paper was presented as part of a lecture at the workshop. It presents the status and possible developments of the two main thermal desalination systems processing large quantities of seawater in the Gulf Cooperation Council, multi-stage flash, and thermal vapor compression systems. Developments of these systems were presented to show how these systems are competing with the more energy-efficient seawater reverse osmosis desalting. © 2013 © 2013 Balaban Desalination Publications. All rights reserved.

  11. RIPP开发的催化重整技术%NEW REFORMING CATALYST DEVELOPED BY RIPP

    Institute of Scientific and Technical Information of China (English)

    濮仲英

    2003-01-01

    To meet the demands for high-octane gasoline and aromatics, catalytic reforming process has been advancing quickly in China. The reforming catalysts developed by RIPP have been used in more than 80% capacity of domestic CCR and SR units. This paper introduces the properties of PS-VI CCR catalyst developed by RIPP in recent years and also the result from commercial units. The PS-VI catalyst has high activity and good selectivity, under the same reaction conditions, the carbon on catalyst was lowered by 26% in mass as compared with that of the reference catalyst. Among the SR reforming catalysts, the new type of PRT series catalysts have excellent performance at low reaction pressure compared with the ref. Cat A. The aromatics and reformate mass yields of PRT catalyst were 2%~3% and 3%, respectively, higher than those of Cat A, and the run length was 30%~40% longer as well, which exhibits good prospect of application.

  12. Development of Novel Resid Hydrometallization Catalyst RDM-3

    Institute of Scientific and Technical Information of China (English)

    Hu Dawei; Niu Chuanfeng; Yang Qinghe; Liu Tao

    2007-01-01

    Based on the reaction mechanism of resid hydrodemetallization,a new catalyst carrier was designed and prepared.As compared with the similar type of catalyst carder,the said new carrier featured a higher pore volume,a larger pore diameter and a weaker surface acidity,which could improve the diffusion performance and stable reaction performance of the catalyst.The active metal components were loaded on the said carrier by a new technique for better metal dispersion,thus the impurity removal rate of the new catalyst,RDM-3,was improved significantly.The commercial test of the RDM-3 catalyst showed that the process of catalyst preparation was stable,the catalyst performance was slightly better than the catalyst prepared in the lab,therefore,the catalyst could be manufactured in commercial scale.

  13. Development of a Novel Type Catalyst SY-2 for Two-Stage Hydrogenation of Pyrolysis Gasoline

    Institute of Scientific and Technical Information of China (English)

    Wu Linmei; Zhang Xuejun; Zhang Zhihua; Wang Fucun

    2004-01-01

    By using the group ⅢB or groupⅦB metals and modulating the characteristics of electric charges on carrier surface, improving the catalyst preparation process and techniques for loading the active metal components, a novel type SY-2 catalyst earmarked for two-stage hydrogenation of pyrolysis gasoline has been developed. The catalyst evaluation results have indicated that the novel catalyst is characterized by a better hydrogenation reaction activity to give higher aromatic yield.

  14. Developing the smallest possible medical cyclotron

    CERN Multimedia

    Katarina Anthony

    2011-01-01

    Imagine a portable medical cyclotron operated in a conventional radioactive facility at a hospital. Imagine a nurse or technician switching it on and producing isotopes at the patient’s bedside. Sounds like science fiction? Think again.   CERN has teamed up with Spain’s national scientific research centre (CIEMAT) to develop an avant-garde cyclotron to be used for Positron Emission Tomography (PET). “We plan to make a cyclotron that doesn't need an insulated building or ‘vault’: a cyclotron small enough to fit inside a hospital lift,” explains Jose Manuel Perez, who is leading the CIEMAT/CERN collaboration. “It will be the smallest possible medical cyclotron for single patient dose production and will dramatically reduce costs for hospitals.” While PET technology has transformed imaging techniques, many of its medical benefits have remained confined to highly specialised hospitals. “Studies have foun...

  15. Designing Catalysts for Clean Technology, Green Chemistry, and Sustainable Development

    Science.gov (United States)

    Meurig Thomas, John; Raja, Robert

    2005-08-01

    There is a pressing need for cleaner fuels (free or aromatics and of minimal sulfur content) or ones that convert chemical energy directly to electricity, silently and without production of noxious oxides and particulates; chemical, petrochemical and pharmaceutical processes that may be conducted in a one-step, solvent-free manner and that use air as the preferred oxidant; and industrial processes that minimize consumption of energy, production of waste, or the use of corrosive, explosive, volatile, and nonbiodegradable materials. All these needs and other desiderata, such as the in situ production and containment of aggressive and hazardous reagents, and the avoidance of use of ecologically harmful elements, may be achieved by designing the appropriate heterogeneous inorganic catalyst, which ideally should be cheap, readily preparable and fully characterizable, preferably under in situ reaction conditions. A range of nanoporous and nanoparticle catalysts that meet most of the stringent demands of sustainable development and responsible (clean) technology is described. Specific examples that are highlighted include the production of adipic acid (precursor of polyamides and urethanes) without the use of concentrated nitric acid nor the production of greenhouse gases such as nitrous oxide; the production of caprolactam (precursor of nylon) without the use of oleum and hydroxylamine sulfate; and the terminal oxyfunctionalization of linear alkanes in air. The topic of biocatalysis and sustainable development is also briefly discussed for the epoxidation of terpenes and fatty acid methyl esters; for the generation of polymers, polylactides, and polyesters; and for the production of 1,3-propanediol from corn.

  16. Study and Pilot Scale Development of Catalyst for Ethylebenzene Synthesis Through Transalkylation of Benzene and Polyethylbenzene

    Institute of Scientific and Technical Information of China (English)

    Wang Jin; Zhang Fengmei; Li Minglin; Hao Xiaoming; Shu Xingtian; He Mingyuan

    2002-01-01

    This paper refers to the results of study and development of benzene and polyethylbenzene transalkylation catalyst (type AEB-1) for synthesis of ethylbenzene. The effect of reaction conditions on the reaction performance of the catalyst was investigated in the pressurized microreactor CDS-900. A transalkylation catalyst with high activity, good selectivity and stability was developed following a 2000-hour test on the activity and stability of the catalyst. The preparation of this catalyst was implemented in pilot scale and this catalyst was tested for activity and stability in a 150 t/a pilot unit for production of ethylbenzene. The test results have shown that this transalkylation catalyst has excellent activity, selectivity and stability. The operation of pilot test unit ran smoothly and the process scheme is viable.

  17. Development of New Generation Catalysts for Selective Hydrodesulfurization of FCC Naphtha

    Institute of Scientific and Technical Information of China (English)

    Chu Yang; Li Mingfeng; Li Huifeng; Qu Jinhua; Nie Hong; Li Dadong

    2009-01-01

    The influence of active metal components of catalyst, additives and catalyst preparation method on the reactiv-ity of catalyst for selective hydrodesulfurization (HDS) of FCC naphtha was investigated, and the RSDS-21 catalyst with high HDS performance and the RSDS-22 catalyst with high selectivity were developed by RIPP. The composite loading of a new series of catalysts for selective HDS of FCC gasoline has demonstrated excellent desulfurization activity and selectivity and can under conventional hydrotreating conditions manufacture clean gasoline product meeting the national Ⅳ emission standard and the Euro Ⅴ emission standard with less loss in antiknock index. The finalized new series of FCC catalysts upon being adopted for selective HDS of FCC naphtha have good adaptability to different feedstocks along with good stability.

  18. DEVELOPMENT POSSIBILITIES OF THE HUNGARIAN-UKRAINIAN

    Directory of Open Access Journals (Sweden)

    Pasztor Szabolcs

    2012-12-01

    questionnaire-based survey. With 432 cases collected from 6 micro regions from the Ukrainian side I can measure the possible cross-border dynamics of the borderless situation. With this method I follow the empirical approach of other regionalists who have come to the conclusion that the opening-up of borders can lead to different dynamism. In this way I try to shed new light on the development possibilities and more increased economic interactions the Hungarian-Ukrainian borderland. The most important conclusion of this paper is the fact that with more intensive cross-border interactions not the neighbouring borderaland benefits but centrally located or larger towns in Hungary. In this way I can point to the fact that borderland dynamics could be quite limited in the research area. With this paper I could confirm previous studies and point to the fact that empirical analysis is needed to understand the local dynamism of a borderless space.

  19. Development of FHDS Type Catalyst for Deep Hydrodesulfurization of Diesel Fuel

    Institute of Scientific and Technical Information of China (English)

    Guo Rong; Yao Yunhai; Zhou Yong

    2005-01-01

    The FHDS type catalyst for deep hydrodesulfurization (HDS) of diesel fuel is a highactivity catalyst developed by FRIPP in order to meet the requirements of Chinese refiners for production of low-sulfur clean diesel fuel containing less than 300 ppm of sulfur. The FH-DS type catalyst has excellent HDS and HDN activity thanks to modification of alumina through incorporating additives, optimization of catalyst preparation and optimal combination of active ingredients.Under low pressure the HDS activity of this catalyst is by 50% higher than that of domestic reference catalysts available in the market and is slightly better than that of foreign reference catalyst. When this catalyst is used for manufacture of clean ultra-low sulfur diesel (containing <30 ppm of S), its volumetric relative desulfurization activity is 46% higher than that of foreign reference catalyst, and this catalyst is an excellent catalyst for manufacture of low-sulfur clean diesel fuel derived from imported high-sulfur Kuwaiti and Arabian crude oils.

  20. A possible role of the dipole moment of the catalyst droplet in nanotube growth, alignment, chirality, and characteristics.

    Science.gov (United States)

    Mohammad, S Noor

    2012-03-02

    Why vapor species land on the surface of the nanoparticle seed for nanotube synthesis is a vital question. An investigation has been carried out to find an answer to it. For this, a model of the dipole moment has been developed. A bimetallic alloy (non-alloy, solid solution) exhibiting the shape of a cap has been assumed to function as the nanoparticle seed. Various features of the dipole moment have been examined. The influence of the dipole moment on nanotube synthesis, alignment, chirality, and characteristics has also been studied. Available experiments on the synthesis of carbon nanotubes employing bimetallic catalysts have been compared with the results from calculations. Close correspondence between the two demonstrates that the catalysts may exhibit a dipole moment and have a crucial role in nanotube synthesis and characteristics. The dipole moment has also been employed to determine why some nanotubes grow vertically, while others are bent. Calculated results appear to explain the basic causes for this. These results suggest that the electric field resulting from the dipole moment of catalysts may be important for the vertical alignment of nanotubes. They may attest to the validity of the model and to the existence of a dipole moment in seeds. Although considered for nanotube syntheses, the results may be applicable to other nanomaterials (nanotubes, nanowires, nanodots).

  1. Possible ways of future social development

    Directory of Open Access Journals (Sweden)

    Zak L.

    2016-01-01

    Full Text Available The authors deal with a question, which is hard to answer considering the context of the future of the social evolution. The authors suppose that one should ask rather about overcoming the current wave of individualism than about overcoming the current form of capitalism. Individualism dismantles any society and it is necessary to react by building stable dual relationships. It highlights the key role of a family. Collectivism, as well as individualism, are not able to create any kind of social structure and lead the society into the liquid of chaos or into the motionless totality. It states that the economic security of various societies is to certain extent affected by all possible production factors and that the reason of the success of their functioning is a balance between power, wealth and public support. It points out that it is necessary to keep a couple and its relationship as a basic element in theory as well as in practice. In legitimate cases of a production practise, it is possible to consider the human individual as the element. It condemns inhumane artificial terms such as “homo economicus”, human resources or human capital. In the conclusions, the authors appeal to restore humanity in society by the contribution of each individual and his interpersonal relationships.

  2. CATALYST TECHNOLOGY DEVELOPMENT FROM MACRO-,MICRO- DOWN TO NANO-SCALE

    Institute of Scientific and Technical Information of China (English)

    Wei Liu

    2005-01-01

    Catalyst and catalytic process technology has been an ever-growing field that involves chemical engineering, chemistry, and material science. A number of excellent review articles and books have been published on the subject. In this work, the author reviews the evolution and development of catalyst products with multi-scale methodology.The catalyst technologies are classified into three levels, macro-scale (reactor size), mini- and micro-scale (catalyst unit),and nano-scale (catalyst intrinsic structures). Innovation at different scales requires different sets of expertise, method,and knowledge. Specific examples of significant impact to practical application are used to illustrate technology development at each scale. The multi-scale analysis enables clear delineation of technology components and their relationship for a catalyst product and catalytic process. Manipulation of catalyst structures at nano-scale to increase intrinsic activity and/or selectivity is considered of large potential for future catalyst product development. Recent research results on Cu-CeO2 and Au-CeO2 composite catalysts for air pollution control and hydrogen production are used to show how novel catalytic properties can be discovered by unique combination of different but common materials at the nano-scale.

  3. A theoretical evaluation of possible transition metal electro-catalysts for N2 reduction

    DEFF Research Database (Denmark)

    Skulason, Egill; Bligaard, Thomas; Gudmundsdottir, Sigrıdur

    2012-01-01

    Theoretical studies of the possibility of forming ammonia electrochemically at ambient temperature and pressure are presented. Density functional theory calculations were used in combination with the computational standard hydrogen electrode to calculate the free energy profile for the reduction ...

  4. TECHNOLOGY DEVELOPMENT FOR IRON AND COBALT FISCHER-TROPSCH CATALYSTS

    Energy Technology Data Exchange (ETDEWEB)

    Burtron H. Davis

    1999-04-30

    The impact of activation procedure on the phase composition of precipitated iron Fischer-Tropsch (FT) catalysts has been studied. Catalyst samples taken during activation and FT synthesis have been characterized by Moessbauer spectroscopy. Formation of iron carbide is necessary for high FT activity. Hydrogen activation of precipitated iron catalysts results in reduction to predominantly metallic iron and Fe{sub 3}O{sub 4}. Metallic iron is not stable under FT 3 4 conditions and is rapidly converted to {epsilon}{prime}-Fe{sub 2.2}C. Activation with carbon monoxide or syngas 2.2 with low hydrogen partial pressure reduces catalysts to {chi}-Fe{sub 5}C{sub 2} and a small amount of 5 2 superparamagnetic carbide. Exposure to FT conditions partially oxidizes iron carbide to Fe{sub 3}O{sub 4}; however, catalysts promoted with potassium or potassium and copper maintain a constant carbide content and activity after the initial oxidation. An unpromoted iron catalyst which was activated with carbon monoxide to produce 94% {chi}-Fe{sub 5}C{sub 2}, deactivated rapidly as the carbide was oxidized to Fe{sub 3}O{sub 4}. No difference in activity, stability or deactivation rate was found for {chi}-Fe{sub 5}C{sub 2} and {epsilon}{prime}-Fe{sub 2.2}C.

  5. Development of Non-Noble Metal Ni-Based Catalysts for Dehydrogenation of Methylcyclohexane

    KAUST Repository

    Al-ShaikhAli, Anaam H.

    2016-11-30

    Liquid organic chemical hydride is a promising candidate for hydrogen storage and transport. Methylcyclohexane (MCH) to toluene (TOL) cycle has been considered as one of the feasible hydrogen carrier systems, but selective dehydrogenation of MCH to TOL has only been achieved using the noble Pt-based catalysts. The aim of this study is to develop non-noble, cost-effective metal catalysts that can show excellent catalytic performance, mainly maintaining high TOL selectivity achievable by Pt based catalysts. Mono-metallic Ni based catalyst is a well-known dehydrogenation catalyst, but the major drawback with Ni is its hydrogenolysis activity to cleave C-C bonds, which leads to inferior selectivity towards dehydrogenation of MCH to TOL. This study elucidate addition of the second metal to Ni based catalyst to improve the TOL selectivity. Herein, ubiquitous bi-metallic nanoparticles catalysts were investigated including (Ni–M, M: Ag, Zn, Sn or In) based catalysts. Among the catalysts investigated, the high TOL selectivity (> 99%) at low conversions was achieved effectively using the supported NiZn catalyst under flow of excess H2. In this work, a combined study of experimental and computational approaches was conducted to determine the main role of Zn over Ni based catalyst in promoting the TOL selectivity. A kinetic study using mono- and bimetallic Ni based catalysts was conducted to elucidate reaction mechanism and site requirement for MCH dehydrogenation reaction. The impact of different reaction conditions (feed compositions, temperature, space velocity and stability) and catalyst properties were evaluated. This study elucidates a distinctive mechanism of MCH dehydrogenation to TOL reaction over the Ni-based catalysts. Distinctive from Pt catalyst, a nearly positive half order with respect to H2 pressure was obtained for mono- and bi-metallic Ni based catalysts. This kinetic data was consistent with rate determining step as (somewhat paradoxically) hydrogenation

  6. Development of new deactivation method for simulation of fluid catalytic cracking equilibrium catalyst

    Indian Academy of Sciences (India)

    T Chiranjeevi; D T Gokak; V Ravikumar; P S Viswanathan

    2014-03-01

    Selection of a good catalyst is the easiest way to increase profitability of a fluid catalytic cracking (FCC) unit. During operation, these catalysts get deactivated due to operation at high temperatures, steam and deposition of metals on the catalyst. Developing a proper catalyst deactivation method is crucial for optimization of a good catalyst for FCC. Conventional laboratory deactivation procedures include direct metal impregnation method, cyclic deactivation method (CDM) and cyclic propylene steaming (CPS). Direct metal impregnation method gives higher coke and gas yields. CDM and CPS methods implementation is very difficult and time-consuming and there is a deviation in coke and gas yield. New rapid deactivation method has been developed to simulate plant equilibrium catalyst (E-Cat) by modifying metal impregnation, steaming and oxidation/reduction procedures. The E-Cat generated through a new deactivation method was characterized for physico-chemical properties using X ray diffraction (XRD), temperature-programmed reduction (TPR), and SEM-EDX and activity studies. XRD studies show that metals are dispersed well on catalyst samples. SEMEDX studies reveal that the morphology of simulated E-Cat and plant E-Cat catalyst particles appear to be same. E-Cat obtained by new deactivationmethod gives better coke and gas yields. Two E-Cats were also generated through CDM and direct metal impregnation method for comparing with the one generated through new method. New deactivation method also significantly reduces the evaluation time.

  7. Development of heterogeneous base catalysts for biodiesel production.

    Science.gov (United States)

    Kawashima, Ayato; Matsubara, Koh; Honda, Katsuhisa

    2008-06-01

    Investigations were conducted on heterogeneous base catalysts for the transesterification of oil aimed at effective production of biodiesel. Thirteen different kinds of metal oxides containing calcium, barium, magnesium, or lanthanum were prepared as catalysts. Their catalytic activities were tested for transesterification at 60 degrees C with a 6:1 molar ratio of methanol to oil and a reaction time of 10h. The calcium-containing catalysts - CaTiO3, CaMnO3, Ca2Fe2O5, CaZrO3, and CaO-CeO2 - showed high activities and approximately 90% yields of methyl ester. Furthermore, catalytic durability tests were performed by repeating the transesterification reaction several times with the calcium-containing catalysts recovered from the previous reaction mixture. It was found that CaZrO3 and CaO-CeO2 show high durability and have the potential to be used in biodiesel production processes as heterogeneous base catalysts.

  8. Scientist-teacher interactions: Catalysts for developing transformational classrooms

    Science.gov (United States)

    McCarty, Robbie Von

    Professional development leading to standards-based teaching practices in U.S. schools is a remarkably subtle and lengthy process. Research indicates that there are many effective tools for teaching through inquiry available to teachers (Lawson, Abraham, & Renner, 1989), but also that teachers continue to present traditional positivistic views of science (Hashweh, 1985; Maor & Taylor, 1995; Zucker, Young, & Luczak, 1996) and appear to view constructivism as a "method" of teaching rather than a way of thinking about learning (Tobin, Tippins, & Gallard, 1984). Teachers are expected to create enriched environments where students can develop the thinking skills of scientists (Roth & Roychoudhury, 1993) but the majority of teachers have never experienced such environments; the involvement of scientists in science education is encouraged by the NRC, AAAS, and NSTA. Teachers and students are expected to act as coresearchers, where negotiation, debate, consensus, and reflection are key. It is believed that scientist and teachers interacting as co-researchers could assist teachers in developing attitudes of freedom in exploration: the essence of science and a mindset that constructivism is a referent, or tool for critical reflection (Tobin, Tippins & Gallard, 1994). This study seeks to identify aspects of scientist-teacher interactions in the field that could serve as catalysts for developing transformational classrooms. Multiple data sources were collected for this study: audiotapes and transcripts of laboratory interactions and informal interviews, written narratives from applications and funding documents, field notes, and personal communications. Data were simultaneously collected, analyzed and coded as a perpetual review of the literature was conducted as in the grounded theory methodology defined by Glaser (1967) and later by Strauss & Corbin (1990). Findings indicate all four teachers valued field experiences in personal ways, developed new understandings of

  9. Accelerating process and catalyst development in reforming reactions with high throughput technologies under industrially relevant conditions

    Energy Technology Data Exchange (ETDEWEB)

    Schunk, S.A.; Bollmann, G.; Froescher, A.; Kaiser, H.; Lange de Oliveira, A.; Roussiere, T.; Wasserschaff, G. [hte Aktiengesellschaft, Heidelberg (Germany); Domke, I. [BASF SE, Ludwigshafen (Germany)

    2010-12-30

    The generation of hydrogen via reforming of a variety of carbon containing feed-stocks in the presence of water is up to date one of the most versatile technologies for the production of hydrogen and syngas. Although these reforming technologies are in principle well established, understood and commercialized, there are still a number of technological challenges that are not solved up to a satisfactorily degree and there is a constant demand for appropriate answers to the challenges posed. High throughput experimentation can be a valuable tool in helping accelerate the development of suitable solutions on the catalyst and process development side. In order to be able to generate test data that are close or identical to process relevant conditions, hte has developed a new technology portfolio of test technologies named Stage-IV technology. In contrast to earlier developments which address more small scale testing on the basis of catalyst volumes of 1ml up to 10 ml under isothermal conditions, our new technology portfolio offers the advantage of test volumes at sub-pilot scale also realizing reactor dimensions close to technical applications. This does not only ensure a good mimic of the hydrodynamic conditions of the technical scale, but also allows a fingerprinting of features like temperature gradients in the catalyst bed which play a large role for catalyst performance. Apart from catalyst tests with granulates when screening for optimized catalyst compositions, the units are designed to accommodate tests with shaped catalysts. In order to demonstrate how these technologies can accelerate catalyst and process development we have chosen technically challenging application examples: (I) Pre-reforming and reforming of methane based feeds which accelerate coking and catalyst deactivation. Higher reaction pressures, high CO{sub 2} contents in the feedgas (which occur typically in sources like bio-gas or certain types of natural gas), the presence of higher alkanes

  10. Development of catalysts and ligands for enantioselective gold catalysis.

    Science.gov (United States)

    Wang, Yi-Ming; Lackner, Aaron D; Toste, F Dean

    2014-03-18

    During the past decade, the use of Au(I) complexes for the catalytic activation of C-C π-bonds has been investigated intensely. Over this time period, the development of homogeneous gold catalysis has been extraordinarily rapid and has yielded a host of mild and selective methods for the formation of carbon-carbon and carbon-heteroatom bonds. The facile formation of new bonds facilitated by gold naturally led to efforts toward rendering these transformations enantioselective. In this Account, we survey the development of catalysts and ligands for enantioselective gold catalysis by our research group as well as related work by others. We also discuss some of our strategies to address the challenges of enantioselective gold(I) catalysis. Early on, our work with enantioselective gold-catalyzed transformations focused on bis(phosphinegold) complexes derived from axially chiral scaffolds. Although these complexes were highly successful in some reactions like cyclopropanation, the careful choice of the weakly coordinating ligand (or counterion) was necessary to obtain high levels of enantioselectivity for the case of allene hydroamination. These counterion effects led us to use the anion itself as a source of chirality, which was successful in the case of allene hydroalkoxylation. In general, these tactics enhance the steric influence around the reactive gold center beyond the two-coordinate ligand environment. The use of binuclear complexes allowed us to use the second gold center and its associated ligand (or counterion) to exert a further steric influence. In a similar vein, we employed a chiral anion (in place of or in addition to a chiral ligand) to move the chiral information closer to the reactive center. In order to expand the scope of reactions amenable to enantioselective gold catalysis to cycloadditions and other carbocyclization processes, we also developed a new class of mononuclear phosphite and phosphoramidite ligands to supplement the previously widely

  11. Water–gas shift catalyst development for energy efficient applications

    NARCIS (Netherlands)

    Hakeem, A.A.

    2014-01-01

    The water–gas shift (WGS) is a reversible, moderately exothermic reaction (1) and is used for the production of hydrogen from CO rich gas streams (synthesis gas). CO + H2O ⇆ CO2 + H2 ΔH°= –41 kJ mol−1 (1) This research has focused on the catalyst

  12. Development and Commercial Application of RFCC Catalyst for Reducing Sulfur Content in Gasoline

    Institute of Scientific and Technical Information of China (English)

    Xu Mingde; Zhu Yuxia; Huang Lei; Hou Dianguo

    2007-01-01

    The sulfur-reducing functional component-the Lewis acid-base pair compound-and associated active zeolite component were developed to prepare the RFCC catalyst DOS for reducing sulfur content in gasoline.The results of catalyst evaluation have revealed that the Lewis acid-base pair compound developed hereby could enhance the conversion of macromolecular sulfur compounds by the catalyst to promote the proceeding of desulfurization reactions,and the synergetic action of the selected zeolite and the Lewis acid-base pair compound could definitely reduce the olefins and sulfur contents in gasoline.The heavy oil conversion capability of the catalyst DOS thus developed was higher coupled with an enhanced resistance to heavy metals contamination to reduce the sulfur content in gasoline by over 20%.The commercial application of this catalyst at the SINOPEC Jiujiang Branch Company has revealed that compared to the GRV-C catalyst the oil slurry yield obtained by the catalyst DOS was reduced along with an improved coke selectivity,an increased total liquid yield,and a decreased olefin content in gasoline.The ratio of sulfur in gasoline/sulfur in feed oil could be reduced by 20.3 m%.

  13. PROGRESS IN CATALYST AND PROCESS DEVELOPMENT FOR LOW SULFUR AND LOW AROMATICS DIESEL PRODUCTION

    Institute of Scientific and Technical Information of China (English)

    ZHOUYong; HANChong-ren

    2003-01-01

    The article includes three parts:①The development and performance of FH-DS catalyst for deep and ultra -deep distillate HDS;②The single stage HDS/HDA hydrotreating process for the production of low sulfur and low aromatics diesels from straight run and coker AGO by using highly active base metal catalyst at moderate pressure;③A two-stage aromatics saturation system utilizing noble metal catalyst in the second stage developed for production of low sulfur and low aromatics diesel from LCO.FDA catalyst developed by FRIPP has high activity for aromatics saturation together with high tolerance for sulfur and nitrogen in the feed.The process is effective in reducing density and increasing cetane number.

  14. Metalloporphyrin catalysts for oxygen reduction developed using computer-aided molecular design

    Energy Technology Data Exchange (ETDEWEB)

    Ryba, G.N.; Hobbs, J.D.; Shelnutt, J.A. [and others

    1996-04-01

    The objective of this project is the development of a new class of metalloporphyrin materials used as catalsyts for use in fuel cell applications. The metalloporphyrins are excellent candidates for use as catalysts at both the anode and cathode. The catalysts reduce oxygen in 1 M potassium hydroxide, as well as in 2 M sulfuric acid. Covalent attachment to carbon supports is being investigated. The computer-aided molecular design is an iterative process, in which experimental results feed back into the design of future catalysts.

  15. ADVANCES ON THE RESEARCH AND DEVELOPMENT OF CATALYSTS FOR TOLUENE DISPROPORTIONATION AND C9 AROMATICS TRANSALKYLATION

    Institute of Scientific and Technical Information of China (English)

    Chen Qingling; Xie Zaiku

    2001-01-01

    Advances on the development of commercial catalysts using in the processes such as Tatoray(Toluene Disproportionation and C9 Aromatics Transalkylation of UOP Company), MTDP (Toluene Disproportionation Process of Mobil Company), S-TDT (Toluene Disproportionation and C9 Aromatics Transalkylation of SRIPT), Trans-Plus, PX-Plus (Selective Toluene Disproportionation of UOP Company) and MSTDP (Selective Toluene Disproportionation Process on Mobils ZSM-5 catalyst) have been reviewed. The trends on the research of the new catalysts such as ZSM-5,Beta, MCM-22, Omega, SAPO and modified Y for the selective toluene disproportionation process and for the toluene disproportionation and C9 aromatics transalkylation have been described.

  16. Development and reactivity tests of Ce-Zr-based Claus catalysts for coal gas cleanup

    Energy Technology Data Exchange (ETDEWEB)

    No-Kuk Park; Dong Cheul Han; Gi Bo Han; Si Ok Ryu; Tae Jin Lee; Ki Jun Yoon [Yeungnam University, Gyeongbuk (Republic of Korea). National Research Laboratory, School of Chemical Engineering and Technology

    2007-09-15

    Claus reaction (2H{sub 2}S + SO{sub 2} {leftrightarrow} 3/nS{sub n} + 2H{sub 2}O) was used to clean the gasified coal gas and the reactivity of several metal oxide-based catalysts on Claus reaction was investigated at various operating conditions. In order to convert H{sub 2}S contained in the gasified coal gas to elemental sulfur during Claus reaction, the catalysts having the high activity under the highly reducing condition with the moisture should be developed. CeO{sub 2}, ZrO{sub 2}, and Ce{sub 1-x}Zr{sub x}O{sub 2} catalysts were prepared for Claus reaction and their reactivity changes due to the existence of the reducing gases and H{sub 2}O in the fuel gas was investigated in this study. The Ce-based catalysts shows that their activity was deteriorated by the reduction of the catalyst due to the reducing gases at higher than 220{sup o}C. Meanwhile, the effect of the reducing gases on the catalytic activity was not considerable at low temperature. The activities of all three catalysts were degraded on the condition that the moisture existed in the test gas. Specifically, the Ce-based catalysts were remarkably deactivated by their sulfation. The Ce-Zr-based catalyst had a high catalytic activity when the reducing gases and the moisture co-existed in the simulated fuel gas. The deactivation of the Ce-Zr-based catalyst was not observed in this study. The lattice oxygen of the Ce-based catalyst was used for the oxidation of H{sub 2}S and the lattice oxygen vacancy on the catalyst was contributed to the reduction of SO{sub 2}. ZrO{sub 2} added to the Ce-Zr-based catalyst improved the redox properties of the catalyst in Claus reaction by increasing the mobility of the lattice oxygen of CeO{sub 2}. 21 refs., 14 figs.

  17. Development of MCM-41 based catalysts for the photo-Fenton's degradation of dye pollutants

    Science.gov (United States)

    Lam, Leung Yuk Frank

    The continuous advancement in most industries has resulted in serious water pollution problems. The industrial effluents contain a variety of highly toxic organics such as dye pollutants. Numerous processes have been demonstrated for treating such pollutants. Among them, photo-Fenton's reaction is effective for organic mineralization by hydroxyl radicals generated from the Fenton's reagents (Fe2+ and H2O2). However, there is a drawback in that it requires a separation system to recover the homogeneous ferrous ion in the treated wastewater. In this research, new heterogeneous Fenton's catalysts are developed to solve such a problem and to achieve an efficient mineralization of dye pollutants. Two methods for catalyst preparation, including sol-gel hydrothermal (SG) and metal-organic chemical vapor deposition (MOCVD) techniques, were studied in this work. For SG-prepared catalysts, the iron element was successfully doped into the MCM-41 structure. These catalysts demonstrated a good catalytic efficiency but leaching of metal ions from the developed catalyst was found. In the MOCVD technique, a rotated tubular reactor system was developed to synthesize Fe/MCM-41 catalyst with uniform metal dispersion. It was found that using oxygen as a carrier gas during metal deposition was able to increase the stability of the deposited metal. In degradation of a model dye pollutant, Orange II, a total of 85% TOC mineralization was achieved at pH 3. A disadvantage of using Fe/MCM-41 was the reduced efficiency at higher pH. Cu/MCM-41 was thus developed and showed better catalytic activities than Fe/MCM-41 at neutral pH. Having the specific catalytic properties of Fe/MCM-41 and Cu/MCM-41, bimetallic (Fe+Cu) catalysts supported on MCM-41 were developed which show better activities in the Orange II mineralization than those monometallic (Fe or Cu) catalysts. The preparation conditions of the catalysts were experimentally optimized. The effects of catalyst dosage, metal loading

  18. Development of Self-Assembled Supramolecular Catalysts and Their Applications to Organic Synthesis

    Institute of Scientific and Technical Information of China (English)

    Shiro IKEGAMI

    2005-01-01

    @@ 1Introduction In modern synthetic organic chemistry, the development of efficient reagent or catalyst recycling systems is regarded as one of the most important topics. We have previously reported a self-assembled process between poly(N-isopropylacrylamide) (PNIPAAm) based polymer ligands and an inorganic species[1]. This process afforded a networked supramolecular complex where the polymers are cross-linked together by the inorganic species. Thus obtained complex was insoluble in water and worked as an efficient triphase catalyst.

  19. Development of Coke-tolerant Transition Metal Catalysts for Dry Reforming of Methane

    KAUST Repository

    Al-Sabban, Bedour E.

    2016-11-07

    Dry reforming of methane (DRM) is an attractive and promising process for the conversion of methane and carbon dioxide which are the most abundant carbon sources into valuable syngas. The produced syngas, which is a mixture of hydrogen and carbon monoxide, can be used as intermediates in the manufacture of numerous chemicals. To achieve high conversion, DRM reaction is operated at high temperatures (700-900 °C) that can cause major drawbacks of catalyst deactivation by carbon deposition, metal sintering or metal oxidation. Therefore, the primary goal is to develop a metal based catalyst for DRM that can completely suppress carbon formation by designing the catalyst composition. The strategy of this work was to synthesize Ni-based catalysts all of which prepared by homogeneous deposition precipitation method (HDP) to produce nanoparticles with narrow size distribution. In addition, control the reactivity of the metal by finely tuning the bimetallic composition and the reaction conditions in terms of reaction temperature and pressure. The highly endothermic dry reforming of methane proceeds via CH4 decomposition to leave surface carbon species, followed by removal of C with CO2-derived species to give CO. Tuning the reactivity of the active metal towards these reactions during DRM allows in principle the catalyst surface to remain active and clean without carbon deposition for a long-term. The initial attempt was to improve the resistance of Ni catalyst towards carbon deposition, therefore, a series of 5 wt.% bimetallic Ni9Pt1 were supported on various metal oxides (Al2O3, CeO2, and ZrO2). The addition of small amount of noble metal improved the stability of the catalyst compared to their monometallic Ni and Pt catalysts, but still high amount of carbon (> 0.1 wt.%) was formed after 24 h of the reaction. The obtained results showed that the catalytic performance, particle size and amount of deposited carbon depends on the nature of support. Among the tested

  20. Recent development of supported monometallic gold as heterogeneous catalyst for selective liquid phase hydrogenation reactions

    Institute of Scientific and Technical Information of China (English)

    Thushara Kandaramath Hari; Zahira Yaakob

    2015-01-01

    The great potential of gold catalysts for chemical conversions in both industrial and environmental concerns has attracted increasing interest in many fields of research. Gold nanoparticles supported by metal oxides with high surface area have been recognized as highly efficient and effective green heterogeneous catalyst even at room temperature under normal reaction conditions, in gas and liquid phase reactions. In the present review, we dis-cuss the recent development of heterogeneous, supported monometal ic gold catalysts for organic transforma-tions emphasizing mainly liquid phase hydrogenation reactions. Discussions on the catalytic synthesis procedures and the promoting effect of other noble metals are omitted since they are already worked out. Appli-cations of heterogeneous, supported monometal ic catalysts for chemoselective hydrogenations in liquid phase are studied including potential articles during the period 2000–2013.

  1. Development of Advanced ISS-WPA Catalysts for Organic Oxidation at Reduced Pressure/Temperature

    Science.gov (United States)

    Yu, Ping; Nalette, Tim; Kayatin, Matthew

    2016-01-01

    The Water Processor Assembly (WPA) at International Space Station (ISS) processes a waste stream via multi-filtration beds, where inorganic and non-volatile organic contaminants are removed, and a catalytic reactor, where low molecular weight organics not removed by the adsorption process are oxidized at elevated pressure in the presence of oxygen and elevated temperature above the normal water boiling point. Operation at an elevated pressure requires a more complex system design compared to a reactor that could operate at ambient pressure. However, catalysts currently available have insufficient activity to achieve complete oxidation of the organic load at a temperature less than the water boiling point and ambient pressure. Therefore, it is highly desirable to develop a more active and efficient catalyst at ambient pressure and a moderate temperature that is less than water boiling temperature. This paper describes our efforts in developing high efficiency water processing catalysts. Different catalyst support structures and coating metals were investigated in subscale reactors and results were compared against the flight WPA catalyst. Detailed improvements achieved on alternate metal catalysts at ambient pressure and 200 F will also be presented in the paper.

  2. Development of a catalyst for conversion of syngas-derived materials to isobutylene

    Energy Technology Data Exchange (ETDEWEB)

    Barger, P.T.; Spehlmann, B.C.; Gajda, G.J.

    1996-10-01

    The initial objective of this program was to develop a catalyst and process for the conversion of synthesis gas to isobutylene via the isosynthesis process. Preliminary work directed at identifying potential catalysts for this reaction did not have promising results. Therefore, the objectives of this program were revised to the development of a catalyst and process for the conversion of synthesis gas to isobutanol. Two approaches have been investigated in this area: the direct conversion of synthesis gas to higher alcohols and indirect conversion via methanol produced using conventional methanol synthesis technology. The isosynthesis reaction for the conversion of synthesis gas to branched hydrocarbons was pioneered by German workers during World War II The primary products of this reaction are either isobutane or isobutylene depending on the catalyst system used. Thoria-based catalysts were found to give the highest yields, but virtually all of the products were alkanes. More recently, there have been several reports of olefin production using ZrO{sub 2}-based. The preliminary work in this program focussed on the evaluation of ZrO{sub 2} and modified ZrO{sub 2} catalysts for the direct conversion of CO/H{sub 2} to isobutylene via the isosynthesis reaction. All of the catalysts and conditions evaluated in this work gave isobutylene yields of less than 4% which is far below that required for an economically viable process. A summary of the key results from this portion of the project is given in Section 3.6. In view of the poor performance of these catalysts and the lack any encouraging results from other research groups working in the isosynthesis area, this approach was abandoned in favor of approaches related to higher alcohols synthesis.

  3. Science games and the development of scientific possible selves.

    Science.gov (United States)

    Beier, Margaret; Miller, Leslie; Wang, Shu

    2012-12-01

    Serious scientific games, especially those that include a virtual apprenticeship component, provide players with realistic experiences in science. This article discusses how science games can influence learning about science and the development of science-oriented possible selves through repeated practice in professional play and through social influences (e.g., peer groups). We first review the theory of possible selves (Markus and Nurius 1986) and discuss the potential of serious scientific games for influencing the development of scientific possible selves. As part of our review, we present a forensic game that inspired our work. Next we present a measure of scientific possible selves and assess its reliability and validity with a sample of middle-school students (N=374). We conclude by discussing the promise of science games and the development of scientific possible selves on both the individual and group levels as a means of inspiring STEM careers among adolescents.

  4. Development of a supported tri-metallic catalyst and evaluation of the catalytic activity in biomass steam gasification.

    Science.gov (United States)

    Li, Jianfen; Xiao, Bo; Yan, Rong; Xu, Xiaorong

    2009-11-01

    A supported tri-metallic catalyst (nano-Ni-La-Fe/gamma-Al(2)O(3)) was developed for tar reduction and enhanced hydrogen production in biomass steam gasification, with focuses on preventing coke deposition and sintering effects to lengthen the lifetime of developed catalysts. The catalyst was prepared by deposition-precipitation method and characterized by various analytical approaches. Following that, the activity of catalysts in biomass steam gasification was investigated in a bench-scale combined fixed bed reactor. With presence of the catalyst, the content of hydrogen in gas products was increased to over 10 vol.%, the tar removal efficiency reached 99% at 1073 K, and more importantly the coke deposition on the catalyst surfaces and sintering effects were avoided, leading to a long lifetime of catalysts.

  5. Refusal as a democratic catalyst for mathematics education development

    Directory of Open Access Journals (Sweden)

    Dalene Swanson

    2012-08-01

    Full Text Available Discussions about the connections between mathematics and democracy amongst the general populace have not been explicitly well rehearsed. A critical relationship with democracy for mathematics education may involve directing and redirecting its purposes. But, we ask, what if the ‘choice’ to not participate in experiences of mathematics education, or in its (redirection, were itself also a critical relationship with mathematics education? What if this refusal and disobedience to the evocative power of mathematics were a democratic action? We argue that consideration of mathematics education for democracy and development must take seriously specific acts of refusal that directly confront the construction of inequality common in most development contexts. Globalisation and development discourses, via citizenship and nationalism, construct relationships with learners and mathematics education in very specific ways that delimit possibilities for egalitarianism and democratic action. But, might such action not be recognised, not as refusal to participate per se, but as a refusal to participate in mathematics education’s colonising and/or globalising neo-liberal gaze? In arguing for the opening of a position of radical equality, we introduce Jacques Rancière to mathematics education theory, noting that for Rancière emancipation is the intentional disregard for ideological narratives such as the ones produced by mathematics education discourses. Thus, we provoke serious reconsideration of the assumptions behind most school improvement and professional development projects, as well as mathematics education policies and practices framed by globalising development discourses, and in the process we challenge our colleagues to consider ‘refusal’ not as deficit or failure, but as a critical position of radical equality in relation to mathematics education.

  6. Combinatorial Development of Water Splitting Catalysts Based on the Oxygen Evolving Complex of Photosystem II

    Energy Technology Data Exchange (ETDEWEB)

    Woodbury, Neal [Arizona State University

    2010-03-31

    The use of methods to create large arrays of potential catalysts for the reaction H2O ½ O2 + 2H+ on the anode of an electrolysis system were investigated. This reaction is half of the overall reaction involved in the splitting of water into hydrogen and oxygen gas. This method consisted of starting with an array of electrodes and developing patterned electrochemical approaches for creating a different, defined peptide at each position in the array. Methods were also developed for measuring the rate of reaction at each point in the array. In this way, the goal was to create and then tests many thousands of possible catalysts simultaneously. This type of approach should lead to an ability to optimize catalytic activity systematically, by iteratively designing and testing new libraries of catalysts. Optimization is important to decrease energy losses (over-potentials) associated with the water splitting reaction and thus for the generation of hydrogen. Most of the efforts in this grant period were focused on developing the chemistry and analytical methods required to create pattern peptide formation either using a photolithography approach or an electrochemical approach for dictating the positions of peptide bond formation. This involved testing a large number of different reactions and conditions. We have been able to find conditions that have allowed us to pattern peptide bond formation on both glass slides using photolithographic methods and on electrode arrays made by the company Combimatrix. Part of this effort involved generating novel approaches for performing mass spectroscopy directly from the patterned arrays. We have also been able to demonstrate the ability to measure current at each electrode due to electrolysis of water. This was performed with customized instrumentation created in collaboration with Combimatrix. In addition, several different molecular designs for peptides that bound metals (primarily Mn) were developed and synthesized and metal

  7. Possibilities and prospects of tourism development in the Russian Arctic

    OpenAIRE

    Lubov Larchenko

    2014-01-01

    Abstract. The article deals with necessity and possibility of tourism industry development as the leading sector of territorial specialization of Arctic regions. The problems are considered and strategic directions are defined for the formation and development of the tourism industry in the Arctic regions of Russia. Analysis of foreign experience in tourism development in the Arctic Regions allows to claim that it could be a powerful instrument in the economic development of Russia's Far Nort...

  8. Quality Service in the International Hotel Sector: A Catalyst for Strategic Human Resource Development?

    Science.gov (United States)

    Maxwell, Gill; Watson, Sandra; Quail, Samantha

    2004-01-01

    This paper analyses the nature of, and relationship between, a quality service initiative and the concept of strategic human resource development. Hilton International is the case study used for this analysis. The principal finding is that the quality initiative is acting as a catalyst for a strategic approach to human resource development to…

  9. Development of catalyst for diesel engine; Diesel engine yo shokubai no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, H.; Furutani, T.; Nagami, T. [Toyota Motor Corp., Aichi (Japan); Aono, N.; Goshima, H.; Kasahara, K. [Cataler Industrial Co. Ltd., Shizuoka (Japan)

    1997-10-01

    The new concept catalyst for diesel engine has been developed. When the exhaust temperature is low, SOF and HC are temporarily adsorbed by the adsorbent within the catalyst and are oxidized as the temperature rise. The process of this development have manifested as follows. (1) The coating material is important factor to govern the oxidation activity. (2) SOF is reduced by the coating material in low temperature less than 200degC. (3) The coating material, which has low SO2 adsorbing rate suppress the sulfate formation at high temperature. 2 refs., 11 figs., 1 tab.

  10. Development of Ultra-Low Platinum Alloy Cathode Catalysts for PEM Fuel Cells

    Energy Technology Data Exchange (ETDEWEB)

    Popov, Branko N. [Univ. of South Carolina, Columbia, SC (United States). Dept. of Chemical Engineering; Weidner, John [Univ. of South Carolina, Columbia, SC (United States)

    2016-01-07

    The goal of this project is to synthesize a low cost PEM fuel cell cathode catalyst and support with optimized average mass activity, stability of mass activity, initial high current density performance under H2/air (power density), and catalyst and support stability able to meet 2017 DOE targets for electrocatalysts for transportation applications. Pt*/ACCS-2 catalyst was synthesized according to a novel methodology developed at USC through: (i) surface modification, (ii) metal catalyzed pyrolysis and (iii) chemical leaching to remove excess meal used to dope the support. Pt* stands for suppressed platinum catalyst synthesized with Co doped platinum. The procedure results in increasing carbon graphitization, inclusion of cobalt in the bulk and formation of non-metallic active sites on the carbon surface. Catalytic activity of the support shows an onset potential of 0.86 V for the oxygen reduction reaction (ORR) with well-defined kinetic and mass transfer regions and 2.5% H2O2 production. Pt*/ACCS-2 catalyst durability under 0.6-1.0 V potential cycling and support stability under 1.0-1.5 V potential cycling was evaluated. The results indicated excellent catalyst and support performance under simulated start-up/shut down operating conditions (1.0 – 1.5 V, 5000 cycles) which satisfy DOE 2017 catalyst and support durability and activity. The 30% Pt*/ACCS-2 catalyst showed high initial mass activity of 0.34 A/mgPGM at 0.9 ViR-free and loss of mass activity of 45% after 30,000 cycles (0.6-1.0 V). The catalyst performance under H2-air fuel cell operating conditions showed only 24 mV (iR-free) loss at 0.8 A/cm2 with an ECSA loss of 42% after 30,000 cycles (0.6-1.0 V). The support stability under 1.0-1.5 V potential cycling showed mass activity loss of 50% and potential loss of 8 mV (iR-free) at 1.5 A/cm2. The ECSA loss was 22% after 5,000 cycles. Furthermore, the Pt*/ACCS-2 catalyst showed an

  11. Development of Hydrocracking Catalyst to Produce High Quality Clean Middle Distillates

    Institute of Scientific and Technical Information of China (English)

    Zhang Xuejun; Zhang Zhihua

    2004-01-01

    A novel hydrocracking Ni-W binary catalyst was tentatively designed and prepared by means of impregnation on mixed supports of modified Y zeolite and amorphous aluminosilicate. The structure and properties of catalyst were extensively characterized by XRD, NH3-TPD, IR and XRF techniques. The performance of catalyst was evaluated by a 100-ml hydrogenation laboratory test unit with two single-stage fixed-bed reactors connected in series. The characterization results showed that the catalyst has a developed and concentrated mesopores distribution, suitable acid sites and acid strength distribution, and uniform and high dispersion of metal sites. Under a high conversion rate of 73.8% with the >350℃ feedstock, a 98. 1m% of C5+yield and 83.5% of middle distillates selectivity were obtained. The yield of middle distillates boiling between 140℃and 370℃ was 68.70m% and its quality could meet the WWFC category Ⅲ specification. It means that this catalyst could be used to produce more high quality clean middle distillates derived from heavy oil hydrocracking. The potential aromatic content of heavy naphtha from 65℃ to 140℃ was 37.5m%. The BMCI value of >370℃ tail oil was 6.6. The heavy naphtha and tail oil are premium feedstocks for catalytic reforming and steam cracker units.

  12. Recent Development of Catalysts for Removal of Volatile Organic Compounds in Flue Gas by Combustion: A Review

    Directory of Open Access Journals (Sweden)

    Marco Tomatis

    2016-01-01

    Full Text Available Volatile organic compounds (VOCs emitted from anthropogenic sources pose direct and indirect hazards to both atmospheric environment and human health due to their contribution to the formation of photochemical smog and potential toxicity including carcinogenicity. Therefore, to abate VOCs emission, the catalytic oxidation process has been extensively studied in laboratories and widely applied in various industries. This report is mainly focused on the benzene, toluene, ethylbenzene, and xylene (BTEX with additional discussion about chlorinated VOCs. This review covers the recent developments in catalytic combustion of VOCs over noble metal catalysts, nonnoble metal catalysts, perovskite catalysts, spinel catalysts, and dual functional adsorbent-catalysts. In addition, the effects of supports, coke formation, and water effects have also been discussed. To develop efficient and cost-effective catalysts for VOCs removal, further research in catalytic oxidation might need to be carried out to strengthen the understanding of catalytic mechanisms involved.

  13. Recent Developments in Doping and Structural Modification of Ceria-Based Catalysts

    Institute of Scientific and Technical Information of China (English)

    Feng Changgen; Fan Guodong

    2005-01-01

    Recent development in the modification of ceria-based catalysts for exhaust gas treatment was reviewed with the dependence of redox properties on structural characters of materials. The doping of ceria with different cations such as rare earth or transition metal oxides results in improvement of structural stability, catalytic function and resistance to sintering at high temperatures. Aging and reduction treatment at high temperatures promote ceria reduction and is beneficial for oxygen storage capacity of the three-way catalysts. Chemical filing technique is very effective in modifying the redox property in the low temperature regions.

  14. Request for Information from entities interested in commercializing Laboratory-developed homogeneous catalyst technology

    Energy Technology Data Exchange (ETDEWEB)

    Intrator, Miranda Huang [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-02-25

    Many industrial catalysts used for homogeneous hydrogenation and dehydrogenation of unsaturated substrates are derived from metal complexes that include (air-sensitive) ligands that are often expensive and difficult to synthesize. In particular, catalysts used for many hydrogenations are based on phosphorus containing ligands (in particular PNP pincer systems). These ligands are often difficult to make, are costly, are constrained to having two carbon atoms in the ligand backbone and are susceptible to oxidation at phosphorus, making their use somewhat complicated. Los Alamos researchers have recently developed a new and novel set of ligands that are based on a NNS (ENENES) skeleton (i.e. no phosphorus donors, just nitrogen and sulfur).

  15. Development of Ni-Based Catalysts for Steam Reforming of Tar Derived from Biomass Pyrolysis

    Institute of Scientific and Technical Information of China (English)

    Dalin LI; Yoshinao NAKAGAWA; Keiichi TOMISHIGE

    2012-01-01

    Nickel catalysts are effective for the steam reforming of tar derived from biomass pyrolysis,but the improvement is needed in terms of activity,stability,suppression of coke deposition and aggregation,and regeneration.Our recent development of Ni-based catalysts for the steam reforming of tar is reviewed including the modification with CeO2 (or MnO),trace Pt,and MgO.The role of additives such as CeO2,MnO,Pt,and MgO is also discussed.

  16. Histidine-containing peptide catalysts developed by a facile library screening method.

    Science.gov (United States)

    Akagawa, Kengo; Sakai, Nobutaka; Kudo, Kazuaki

    2015-02-02

    Although peptide catalysts have a high potential for the use as organocatalysts, the optimization of peptide sequences is laborious and time-consuming. To address this issue, a facile screening method for finding efficient aminocatalysts from a peptide library has been developed. In the screening for the Michael addition of a malonate to an enal, a dye-labeled product is immobilized on resin-bound peptides through reductive amination to visualize active catalysts. This procedure allows for the monitoring of the reactivity of entire peptides without modifying the resin beads beforehand. Peptides containing histidine at an appropriate position were identified by this method. A novel function of the histidyl residue, which enhances the binding of a substrate to the catalyst by capturing an iminium intermediate, was indicated.

  17. Development and Commercial Application of Ultra-Low Pressure Naphtha Reforming Technology with Continuous Catalyst Regeneration

    Institute of Scientific and Technical Information of China (English)

    Ma Aizeng; Xu Youchun; Yang Dong; Zhang Xinkuan; Wang Jieguang

    2013-01-01

    The development history and major technological innovations of the ultra-low pressure naphtha reforming tech-nology with continuous catalyst regeneration in China were introduced. This technology had been adopted by the 1.0 Mt/a CCR unit at the Guangzhou Company. The appropriate catalyst was selected to meet the demand of the unit capacity, the feedstock, and the product slate. The design parameters, including the reaction pressure, the octane number of C5+ liquid product, the reaction temperature, the space velocity, the hydrogen/oil molar ratio, and the catalyst circulating rate, were chosen based on the study of process conditions and parameters. The commercial test results showed that the research oc-tane number of C5+ product reached 104 when the capacity of the CCR unit was 100% and 115% of the design value. The other technical targets attained or exceeded the expected value.

  18. Visible-Light-Responsive Catalyst Development for Volatile Organic Carbon Remediation Project

    Science.gov (United States)

    Zeitlin, Nancy; Hintze, Paul E.; Coutts, Janelle

    2015-01-01

    Photocatalysis is a process in which light energy is used to 'activate' oxidation/reduction reactions. Unmodified titanium dioxide (TiO2), a common photocatalyst, requires high-energy UV light for activation due to its large band gap (3.2 eV). Modification of TiO2 can reduce this band gap, leading to visible-light-responsive (VLR) photocatalysts. These catalysts can utilize solar and/or visible wavelength LED lamps as an activation source, replacing mercury-containing UV lamps, to create a "greener," more energy-efficient means for air and water revitalization. Recently, KSC developed several VLR catalysts that, on preliminary evaluation, possessed high catalytic activity within the visible spectrum; these samples out-performed existing commercial VLR catalysts.

  19. Development and screening of selective catalysts for the synthesis of clean liquid fuels

    NARCIS (Netherlands)

    Scholten, J.J.F.; Xiaoding, Xu; Drecken, von der C.-B.; Höhlein, B.; Mausbeck, D.; Ross, J.R.H.; Slaa, J.; Hoffmann, U.; Kunz, U.; Stölting, H.

    1994-01-01

    This article is a compilation of the research carried out under EEC contract EN3V-0400-D at the Institut für Energieverfahrenstechnik in Jülich and at the Faculty of Chemical Technology and Materials Science, Delft, concerning the development and screening of copper/cobalt-based catalysts for the sy

  20. Technology development for cobalt F-T catalysts. Quarterly technical progress report No. 5, October 1, 1993--December 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Singleton, A.H.

    1994-05-31

    The goal of this project is the development of a commercially viable, cobalt-based Fischer-Tropsch (F-T) catalyst for use in a slurry bubble column reactor. Cobalt-based catalysts have long been known as being active for F-T synthesis. They typically possess greater activity than iron-based catalysts, historically the predominant catalyst being used commercially for the conversion of syngas based on coal, but possess two disadvantages that somewhat lessen its value: (1) cobalt tends to make more methane than iron does, and (2) cobalt is less versatile with low H{sub 2}/CO ratio syngas due to its lack of water-gas shift activity. Therefore, the major objectives of this work are (1) to develop a cobalt-based F-T catalyst with low (< 5 %) methane selectivity, (2) to develop a cobalt-based F-T catalyst with water-gas shift activity, and (3) to combine both these improvements into one catalyst. It will be demonstrated that these catalysts have the desired activity, selectivity, and life, and can be made reproducibly. Following this experimental work, a design and a cost estimate will be prepared for a plant to produce sufficient quantities of catalyst for scale-up studies.

  1. Development of Auto Exhaust Catalysts and Associated Application of Rare Earths in China

    Institute of Scientific and Technical Information of China (English)

    吴晓东; 翁端

    2004-01-01

    There are at least three obvious trends in the developments of automotive market in China: the evolution of emission standards from Euro Ⅱ to Euro Ⅲ, the demand of lean-burn gasoline engine and the time of diesel vehicles. The latest application and advances of exhaust catalysts by Chinese researchers, using some high effcient, economical and durable methods to meet these changes in emission regulations laws and engine technologies, were described. Rare earth oxides, such as lanthana, ceria-based solid solutions and perovskite-type oxides, are widely used as excellent promoters for thermal stability, oxygen storage capacity and oxidation/reduction activity in these catalysts. Four phases in the development of the auto exhaust catalyst industry in China since the mid 1970s were reviewed. It is argued that China will become the center of global auto exhaust catalysts industry in the next decades with its economic, technical and environmental incentives, which greatly depends on the research and development of rare earth.

  2. Hydrocracking for oriented conversion of heavy oils. Recent trends for catalyst development

    Energy Technology Data Exchange (ETDEWEB)

    Bertoncini, F.; Bonduelle, A.; Simon, L.J. [IFP Energies nouvelles, Lyon Establishment, Solaize (France). Catalysis and separation Division; Raybaud, P.; Dulot, H. [IFP Energies nouvelles, Lyon Establishment, Solaize (France). Process Desing Modeling Division

    2011-07-01

    As a result of the global economic crisis since the end of 2008, HCK operators have been looking to increase the profitability of the unit by processing heavier feed streams, including sourer VGO. These feeds present the drawbacks of increased H{sub 2} consumption, lower products yields and quality, and reduction in cycle lengths. Along with optimised process parameters, catalysts manufacturers are also investigating novel formulations to deal with challenging feeds. This lecture briefly summarizes the market trends (fuel demand, refinery's product specification) and the driving forces for HCK catalyst development in order to face these new challenges. Finally, this lecture highlights the innovating trends for HCK catalyst's development. Overview of various ideas developed recently in our research laboratory about (i) rational approaches for the atomic scale design of active phases (morphology, preparation, inhibitor effects), (ii) new preparations of transition metal sulphides for maximising the hydrogenating function (precursors, activation,.), (iii) rational approaches of HCK acidic supports for maximizing the selectivity and (iv) better understanding of HCK reactions. These improvements will be discussed in term of improvement of activity and selectivity of HCK catalyst to cope with future market needs. (orig.)

  3. Evaluation of different catalysts and development of a new catalyst for the reduction of CO2 to graphite

    Science.gov (United States)

    Tschekalinskij, Alexander; Schindler, Matthias; Kretschmer, Wolfgang

    2016-02-01

    We present an evaluation of different catalysts, methods and parameters for the catalytic reduction of CO2 for 14C-AMS graphite targets for radiocarbon measurement at the Physical Institute of the University Erlangen-Nuremberg in Germany. Currently 10 μm iron powder is used as a catalyst to reduce carbon dioxide to graphite following our standard protocol. An optimal catalyst should provide a short reduction time, no additional fractionation effects, a good reduction yield, lack sintering and should not contain any amounts of both "dead" and "modern" carbon. Seven purchasable catalysts have been evaluated regarding this criteria. Further, the method using zinc and titanium hydride instead of hydrogen gas and the water-trap has been applied to our system and the effect of the water-trap temperature on the reduction time has been tested. A self-made catalyst was produced using aluminum oxide impregnated with iron nitrate. The results of this study indicate three good catalysts and show the success of the applied methods on standard samples like Ox II and Alfa graphite.

  4. The Arctic zone: possibilities and risks of development

    Science.gov (United States)

    Sentsov, A.; Bolsunovskaya, Y.; Melnikovich, E.

    2016-09-01

    The authors analyze the Arctic region innovative possibilities from the perspective of political ideology and strategy. The Arctic region with its natural resources and high economic potential attracts many companies and it has become an important area of transnational development. At present, the Arctic region development is of great importance in terms of natural resource management and political system development. However, the most important development issue in the Arctic is a great risk of different countries’ competing interests in economic, political, and legal context. These are challenges for international partnership creating in the Arctic zone, Russian future model developing for the Arctic, and recognition of the Arctic as an important resource for the Russians. The Russian economic, military, and political expansion in the Arctic region has the potential to strengthen the national positions. The authors present interesting options for minimizing and eliminating political risks during the Arctic territories development and define an effective future planning model for the Russian Arctic.

  5. Development of wet-proofed catalyst and catalytic exchange process for tritium extraction

    Energy Technology Data Exchange (ETDEWEB)

    Song, Myung Jae; Son, Soon Hwan; Chung, Yang Gun; Lee, Gab Bock [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center

    1995-12-31

    To apply a liquid phase catalytic exchange(LPCE) process for the tritium extraction from tritiated heavy water, the wet proofed catalyst to allow the hydrogen isotopic exchange reaction between liquid water and hydrogen gas was developed. A styrene divinyl benzene copolymer was selected as am effective catalyst support and prepared by suspension copolymerization. After post-treatment, final catalyst supports were dipped in chloroplatinic acid solution. The catalyst support had a good physical properties at a particular preparation condition. The catalytic performance was successfully verified through hydrogen isotopic exchange reaction in the exchange column. A mathematical model for the tritium removal process consisted of LPCE front-ended process and cryogenic distillation process was established using the NTU-HTU method for LPCE column and the FUG method for cryogenic distillation column, respectively. A computer program was developed using the model and then used to investigate optimum design variables which affect the size of columns and tritium inventory (author). 84 refs., 113 figs.

  6. Development of improved iron Fischer-Tropsch catalysts. Final technical report: Project 6464

    Energy Technology Data Exchange (ETDEWEB)

    Bukur, D.B.; Ledakowicz, S.; Koranne, M. [Texas A and M Univ., College Station, TX (United States). Dept. of Chemical Engineering] [and others

    1994-02-28

    Despite the current worldwide oil glut, the United States will ultimately require large-scale production of liquid (transportation) fuels from coal. Slurry phase Fischer Tropsch (FT) technology, with its versatile product slate, may be expected to play a major role in production of transportation fuels via indirect coal liquefaction. Texas A&M University (TAMU) with sponsorship from the US Department of Energy, Center for Energy and Mineral Resources at TAMU, Texas Higher Education Coordinating Board, and Air Products and Chemicals, Inc., has been working on development of improved iron FT catalysts and characterization of hydrodynamic parameters in two- and three-phase bubble columns with FT derived waxes. Our previous studies have provided an improved understanding of the role of promoters (Cu and K), binders (silica) and pretreatment procedures on catalyst activity, selectivity and longevity (deactivation). The objective of the present contract was to develop improved catalysts with enhanced slurry phase activity and higher selectivity to liquid fuels and wax. This was accomplished through systematic studies of the effects of pretreatment procedures and variations in catalyst composition (promoters and binders). The major accomplishments and results in each of these two main areas of research are summarized here.

  7. Novel Catalyst Development for Synthetic Endothermic Fuels Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Physical Sciences Incorporated (PSI) and United Technologies Research Center (UTRC) propose to develop, characterize, and evaluate the performance of innovative...

  8. Development of sustainable Palladium-based catalysts for removal of persistent contaminants from drinking water

    Science.gov (United States)

    Shuai, Danmeng

    Pd-based catalytic reduction has emerged as an advanced treatment technology for drinking water decontamination, and a suite of persistent contaminants including oxyanions, N-nitrosoamines, and halogenated compounds are amenable to catalytic reduction. The primary goal of this study is to develop novel Pd-based catalysts with enhanced performance (i.e., activity, selectivity, and sustainability) to remove contaminants from drinking water. The effects of water quality (i.e., co-contaminants in water matrix), catalyst support, and catalyst metal were explored, and they provide insights for preparing catalysts with faster kinetics, higher selectivity, and extended lifetime. Azo dyes are wide-spread contaminants, and they are potentially co-exisiting with target contaminants amenable for catalytic removal. The probe azo dye methyl orange (MO) enhanced catalytic reduction kinetics of a suite of oxyanions (i.e., nitrate, nitrite, bromate, chlorate, and perchlorate) and diatrizoate significantly but not N-nitrosodimethylamine (NDMA) with a variety of Pd-based catalysts. Nitrate was selected as a probe contaminant, and several different azo dyes (i.e., (methyl orange, methyl red, fast yellow AB, metanil yellow, acid orange 7, congo red, eriochrome black T, acid red 27, acid yellow 11, and acid yellow 17) were evaluated for their ability to enhance reduction. A hydrogen atom shuttling mechanism was proposed and a kinetic model was proposed based on Bronsted-Evans-Polanyi (BEP) theory, and they suggest sorbed azo dyes and reduced hydrazo dyes shuttle hydrogen atoms to oxyanions or diatrizoate to enhance their reduction kinetics. Next, vapor-grown carbon nanofiber (CNF) supports were used to explore the effects of Pd nanoparticle size and interior versus exterior loading on nitrite reduction activity and selectivity (i.e., dinitrogen over ammonia production). In order to evaluate the amount of interior versus exterior loading of Pd nanoparticles, a fast and accurate geometric

  9. Development of biogas reforming Ni-La-Al catalysts for fuel cells

    Science.gov (United States)

    Benito, M.; García, S.; Ferreira-Aparicio, P.; Serrano, L. García; Daza, L.

    In this work, the results obtained for Ni-La-Al catalysts developed in our laboratory for biogas reforming are presented. The catalyst 5% Ni/5% La 2O 3-γ-Al 2O 3 has operated under kinetic control conditions for more than 40 h at 700 °C and feeding CH 4/CO 2 ratio 1/1, similar to the composition presented in biogas streams, being observed a stable behaviour. Reaction parameters studied to evaluate the catalyst activity were H 2/CO and CH 4/CO 2 conversion ratio obtained. On the basis of a CH 4 conversion of 6.5%, CH 4/CO 2 conversion ratio achieved 0.48 and H 2/CO ratio obtained was 0.43. By comparison of experimental results to equilibrium prediction for such conditions, is detectable a lower progress of reverse water gas shift reaction. This fact increases the H 2/CO ratio obtained and therefore the hydrogen production. The higher H 2/CO and a CH 4/CO 2 conversion ratio in comparison to CH 4 one close to equilibrium is due to the carbon deposits gasification which avoids catalyst deactivation. A thermodynamic analysis about the application of dry and combined methane reforming to hydrogen production for fuel cells application is presented. Data obtained by process simulation considering a Peng-Robinson thermodynamic model, allows optimizing process conditions depending on biogas composition.

  10. Development of Asymmetric Hydrogenation Catalysts via High Throughput Experimentation

    NARCIS (Netherlands)

    Vries, J.G. de; Lefort, L.

    2013-01-01

    The dynamics of drugs discovery imposes severe time constraints on the development chemist in charge of implementing the large scale production of a new Active Pharmaceutical Ingredient (API). This results in the use of well-established and robust transformations at the expense of the cost-efficienc

  11. Recent advances in the development of alkyne metathesis catalysts

    Directory of Open Access Journals (Sweden)

    Matthias Tamm

    2011-01-01

    Full Text Available The number of well-defined molybdenum and tungsten alkylidyne complexes that are able to catalyze alkyne metathesis reactions efficiently has been significantly expanded in recent years.The latest developments in this field featuring highly active imidazolin-2-iminato- and silanolate–alkylidyne complexes are outlined in this review.

  12. Foreign Direct Investment as a Catalyst for Industrial Development

    OpenAIRE

    Markusen, James R.; Venables, Anthony J

    1997-01-01

    How does an FDI project affect local firms in the same industry? Competition in the" product and factor markets tends to reduce profits of local firms, but linkage effects to supplier" industries may reduce input costs and raise profits. This paper develops an analytical framework" to assess these effects. Circumstances in which FDI is complementary to local industry are" established, and it is shown how FDI may lead to the establishment of local industrial sectors. " These sectors may grow t...

  13. Development and Application of a Reductive Titanium Dioxide Catalyst

    OpenAIRE

    Chen, Matthew Lee

    2015-01-01

    A large population in the United States relies on groundwater as the drinking water source. One typical pollutant of groundwater is nitrate (NO3-). Individuals that have consumed water with high levels of nitrate are at the risk of methemoglobonemia. Due to the prevalence of nitrate contamination in groundwater, various methods have been developed to remove nitrate. These methods include ion exchange, reverse osmosis, and biological denitrification. Photocatalysts have been used for wate...

  14. Developing Enzyme and Biomimetic Catalysts for Upgrading Heavy Crudes via Biological Hydrogenation and Hydrodesulfurization

    Energy Technology Data Exchange (ETDEWEB)

    Borole, A P

    2006-08-22

    The recovery and conversion of heavy oils is limited due to the high viscosity of these crudes and their high heteroatom content. Conventional technology relies on thermochemical hydrogenation and hydrodesulfurization to address these problems and is energy intensive due to the high operating temperature and pressure. This project was initiated to explore biological catalysts for adding hydrogen to the heavy oil molecules. Biological enzymes are efficient at hydrogen splitting at very mild conditions such as room temperature and pressure, however, they are very specific in terms of the substrates they hydrogenate. The goal of the project was to investigate how the specificity of these enzymes can be altered to develop catalysts for oil upgrading. Three approaches were used. First was to perform chemical modification of the enzyme surface to improve binding of other non-natural substrates. Second approach was to expose the deeply buried catalytic active site of the enzyme by removal of protein scaffolding to enable better interaction with other substrates. The third approach was based on molecular biology to develop genetically engineered systems for enabling targeted structural changes in the enzyme. The first approach was found to be limited in success due to the non-specificity of the chemical modification and inability to target the region near the active site or the site of substrate binding. The second approach produced a smaller catalyst capable of catalyzing hydrogen splitting, however, further experimentation is needed to address reproducibility and stability issues. The third approach which targeted cloning of hydrogenase in alternate hosts demonstrated progress, although further work is necessary to complete the cloning process. The complex nature of the hydrogenase enzyme structure-function relationship and role of various ligands in the protein require significant more research to better understand the enzyme and to enable success in strategies in

  15. CATALYST ACTIVITY MAINTENANCE FOR THE LIQUID PHASE SYNTHESIS GAS-TO-DIMETHYL ETHER PROCESS PART II: DEVELOPMENT OF ALUMINUM PHOSPHATE AS THE DEHYDRATION CATALYST FOR THE SINGLE-STEP LIQUID PHASE SYNGAS-TO-DME PROCESS

    Energy Technology Data Exchange (ETDEWEB)

    Xiang-Dong Peng

    2002-05-01

    At the heart of the single-step liquid phase syngas-to-DME process (LPDME{trademark}) is a catalyst system that can be active as well as stable. In the Alternative Fuels I program, a dual-catalyst system containing a Cu-based commercial methanol synthesis catalyst (BASF S3-86) and a commercial dehydration material ({gamma}-alumina) was demonstrated. It provided the productivity and selectivity expected from the LPDME process. However, the catalyst system deactivated too rapidly to warrant a viable commercial process [1]. The mechanistic investigation in the early part of the DOE's Alternative Fuels II program revealed that the accelerated catalyst deactivation under LPDME conditions is due to detrimental interaction between the methanol synthesis catalyst and methanol dehydration catalyst [2,3]. The interaction was attributed to migration of Cu- and/or Zn-containing species from the synthesis catalyst to the dehydration catalyst. Identification of a dehydration catalyst that did not lead to this detrimental interaction while retaining adequate dehydration activity was elusive. Twenty-nine different dehydration materials were tested, but none showed the desired performance [2]. The search came to a turning point when aluminum phosphate was tested. This amorphous material is prepared by precipitating a solution containing Al(NO{sub 3}){sub 3} and H{sub 3}PO{sub 4} with NH{sub 4}OH, followed by washing, drying and calcination. The aluminum phosphate catalyst has adequate dehydration activity and good stability. It can co-exist with the Cu-based methanol synthesis catalyst without negatively affecting the latter catalyst's stability. This report documents the details of the development of this catalyst. These include initial leads, efforts in improving activity and stability, investigation and development of the best preparation parameters and procedures, mechanistic understanding and resulting preparation guidelines, and the accomplishments of this work.

  16. Development of Non-Platinum Catalysts for Intermediate Temperature Water Electrolysis

    DEFF Research Database (Denmark)

    Nikiforov, Aleksey Valerievich; Petrushina, Irina Michailovna; Bjerrum, Niels J.

    2014-01-01

    the best compromise in metal-hydrogen bond strength1,2. Due to economic reasons there is a huge interest in replacing Pt by cheaper alternatives and much effort have been made in finding novel catalysts for Hydrogen Evolution Reaction (HER)3,4. Many anhydrous proton conductors have been investigated...... are at the stage of commercial development. However, there is a great challenge for their widespread commercialization: high cost and low abundance of the electrocatalytic materials (Pt, IrO2) and use of Ti or other expensive construction materials. On the cathode side, the most active catalyst is Pt exhibiting...... it is important to simulate conditions of those presented in the assembled operational electrolyzer. In this work a molten KH2PO4 will be used as an electrolyte while screening performance of various transition metals and their carbides at higher temperature (Figure 1). In this work will be shown that coatings...

  17. A membraneless alkaline direct liquid fuel cell (DLFC) platform developed with a catalyst-selective strategy

    Science.gov (United States)

    Yu, Xingwen; Pascual, Emilio J.; Wauson, Joshua C.; Manthiram, Arumugam

    2016-11-01

    With a logical management of the catalyst selectivity, we present a scalable, membraneless alkaline direct liquid fuel cell (DLFC) platform. The uniqueness of this innovation is that the inexpensive (non-platinum) cathode catalysts, based on strongly coupled transition-metal-oxide nanocrystals and nano-structured carbon materials (e. g., NiCo2O4 nano-particles on a nitrogen-doped graphene and MnNiCoO4 nano-particles on a nitrogen-doped multi-wall carbon nanotube), exhibit high activity for the oxygen reduction reaction (ORR) but without activity for the anode fuel oxidation reaction (FOR). Therefore, operation of the DLFCs allows the anode fuel to freely enter the cathode. This strategy avoids the reliance on expensive or difficult-to-develop cation- or anion-exchange membranes and circumvents the scalability concerns of the conventional membraneless DLFCs that are operated under a laminar-flow principle. With proper catalyst selectivity, a variety of organic liquids can be used as anode fuels. The high power density delivered by the membraneless DLFCs with inexpensive components and safe fuels can enable the development of not only small-scale portable power sources but also large-scale energy generation systems for transportation and stationary storage.

  18. Commercial Application of the CTV-IV Type Catalyst for Synthesis of Vinyl Acetate Developed by Shanghai Petrochemical Research Instit

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The CTV-IV type catalyst for synthesis of vinyl acetate developed by the SINOPEC Shanghai Petrochemical Research Institute (SPRI) has been successfully applied on the #2 vinyl acetate unit at SINOPEC's Shanghai Petrochemical Company.

  19. Enhanced development of a catalyst chamber for the decomposition of up to 1.0 kg/s hydrogen peroxide

    Science.gov (United States)

    Božić, Ognjan; Porrmann, Dennis; Lancelle, Daniel; May, Stefan

    2016-06-01

    A new innovative hybrid rocket engine concept is developed within the AHRES program of the German Aerospace Center (DLR). This rocket engine based on hydroxyl-terminated polybutadiene (HTPB) with metallic additives as solid fuel and high test peroxide (HTP) as liquid oxidizer. Instead of a conventional ignition system, a catalyst chamber with a silver mesh catalyst is designed to decompose the HTP. The newly modified catalyst chamber is able to decompose up to 1.0 kg/s of 87.5 wt% HTP. Used as a monopropellant thruster, this equals an average thrust of 1600 N. The catalyst chamber is designed using the self-developed software tool SHAKIRA. The applied kinetic law, which determines catalytic decomposition of HTP within the catalyst chamber, is given and commented. Several calculations are carried out to determine the appropriate geometry for complete decomposition with a minimum of catalyst material. A number of tests under steady state conditions are carried out, using 87.5 wt% HTP with different flow rates and a constant amount of catalyst material. To verify the decomposition, the temperature is measured and compared with the theoretical prediction. The experimental results show good agreement with the results generated by the design tool. The developed catalyst chamber provides a simple, reliable ignition system for hybrid rocket propulsion systems based on hydrogen peroxide as oxidizer. This system is capable for multiple reignition. The developed hardware and software can be used to design full scale monopropellant thrusters based on HTP and catalyst chambers for hybrid rocket engines.

  20. Development of Self-Organized Polymeric Lewis Acid-Catalysts for the Zero-Emission Synthesis of 2-Amino Alcohols

    Institute of Scientific and Technical Information of China (English)

    J. Inanaga

    2005-01-01

    @@ 1Introduction β-Amino alcohols are versatile synthetic intermediates for a wide range of biologically active natural and unnatural products. They can also serve as good chiral ligands for some asymmetric metal complex catalysts.The nucleophilic ring-opening of epoxides with an amine is one of the most efficient routes to obtain such β-amino alcohols with 1,2-trans stereochemistry. Therefore, various homogeneous catalysts have been developed for this transformation. Meanwhile, the development of efficient heterogeneous catalysts that can be easily prepared, recovered, and reused without losing their activities has currently received much attention from a practical and environmental point of view, and not a few such reusable heterogeneous catalysts (e. g., supported on inorganic materials or insoluble polymers) have been developed[1]. In general, however, they tend to show lower catalytic activities and selectivities compared to the corresponding homogeneous one, and the preparation of them are often tedious.

  1. Development of biogas reforming Ni-La-Al catalysts for fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Benito, M.; Garcia, S.; Ferreira-Aparicio, P.; Serrano, L. Garcia; Daza, L. [Instituto de Catalisis y Petroleoquimica (CSIC), C/ Marie Curie 2, Campus Cantoblanco, 28049 Madrid (Spain)

    2007-06-10

    In this work, the results obtained for Ni-La-Al catalysts developed in our laboratory for biogas reforming are presented. The catalyst 5% Ni/5% La{sub 2}O{sub 3}-{gamma}-Al{sub 2}O{sub 3} has operated under kinetic control conditions for more than 40 h at 700 C and feeding CH{sub 4}/CO{sub 2} ratio 1/1, similar to the composition presented in biogas streams, being observed a stable behaviour. Reaction parameters studied to evaluate the catalyst activity were H{sub 2}/CO and CH{sub 4}/CO{sub 2} conversion ratio obtained. On the basis of a CH{sub 4} conversion of 6.5%, CH{sub 4}/CO{sub 2} conversion ratio achieved 0.48 and H{sub 2}/CO ratio obtained was 0.43. By comparison of experimental results to equilibrium prediction for such conditions, is detectable a lower progress of reverse water gas shift reaction. This fact increases the H{sub 2}/CO ratio obtained and therefore the hydrogen production. The higher H{sub 2}/CO and a CH{sub 4}/CO{sub 2} conversion ratio in comparison to CH{sub 4} one close to equilibrium is due to the carbon deposits gasification which avoids catalyst deactivation. A thermodynamic analysis about the application of dry and combined methane reforming to hydrogen production for fuel cells application is presented. Data obtained by process simulation considering a Peng-Robinson thermodynamic model, allows optimizing process conditions depending on biogas composition. (author)

  2. [Cyclers for APD: current potential and possible developments].

    Science.gov (United States)

    Corciulo, R; Russo, R

    2009-01-01

    The use of automated peritoneal dialysis (APD) is rapidly increasing worldwide. The success of this treatment is closely linked to the development of new mechanical devices (cyclers). At present, the cyclers available in Italy are the Baxter Home Choice Pro, the Fresenius Sleep Safe, and the Gambro Serena. Today's cyclers are characterized by a user-friendly, intuitive interface and sophisticated software. The miniaturization of components has led to a significant reduction of the weight and size of these machines and great flexibility in treatment scheduling. The memory card (patient card) and the possibility of remote control (teledialysis) allow continuous monitoring of the patients and their compliance to treatment. The cyclers of the future could optimize their performance by biosensors able to assess, in real time, the dialysis dose while sensors placed on the drainage line could facilitate the early diagnosis of peritonitis. The peritoneal clearance could be increased with the development of continuous-flow peritoneal dialysis (CFPD). Finally, the introduction of cyclers able to prepare individually tailored solutions different from the standard ones could better meet the clinical needs of the patients and reduce the exposure of the peritoneal membrane to high concentrations of glucose.

  3. Evolution and current development of Transversal Themes: possibilities and limits

    Directory of Open Access Journals (Sweden)

    Carlos Rosales López

    2015-02-01

    Full Text Available The aim of this study was to determine the characteristics of the evolution and current development of transversal themes in education, considering them basically as important social cuestions with great influence in the overall education of the student. Specifically it seeks to clarify the level of preparation and dedication of teachers and schools to teach them. To do this, legislation used in our country (organics laws and decrees curriculum were analyzed and also the contribution of outstanding educators, institutions and researchers. We analyzed the characteristics of transversal themes in the educational project and the teaching program, its development in the clasroom and its projection out of it through the help of family and community. Conclusions about their current status (possibilities and limitations are derived and future proposals are made on the improvement of initial and ongoing training of teachers, to increase their collegiate or cooperative work of planning, intervention and evaluation, increased media and counseling in use, the need for increased communication and collaboration with families and other community institutions.How to reference this articleRosales López, C. (2015. Evolución y desarrollo actual de los Temas Transversales: posibilidades y límites. Foro de Educación, 13(18, pp. 143-160. doi: http://dx.doi.org/10.14516/fde.2015.013.018.008

  4. Development of structural characterisation tools for catalysts; Developpement d'outils de caracterisation structurale de catalyseurs

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, J.

    1999-10-01

    Because of the diversity of their compositions and structures, and the treatments needed to render them active, heterogeneous catalysts present a major challenge in structural characterisation. Electron microscopy provides textural and structural information at the scale of the individual particle. We have been able to analyse epitaxial relationships between nanometer size particles and their support and to determine which crystal faces are most exposed. Chemical analysis can be carried out on individual particles in a bimetallic catalyst. Limitations of this technique are shown for characterisation of catalysts at the atomic scale or in reactive conditions. Here, global analysis methods based on X-ray absorption and diffraction provide more information. W-ray absorption fine structure analysis has been applied to sub-nanometer size particles in platinum based catalysts to explore interactions between the metal and reactive gases such as hydrocarbons and H{sub 2}S. Differences observed between mono-metallic and bimetallic solids lead to structural models to explain differences in catalyst reactivity. X-ray diffraction, combined with electron microscopy, shows the presence of different forms of extra-framework aluminium is steamed zeolites. Quantification of some these forms has been possible and a study of their reactivity towards different de-aluminating agents has been achieved. Work in progress shows the advantages of a combination of X-ray diffraction and absorption to study decomposition of hydrotalcites to form mixed oxides as well as possibilities in infra-red spectroscopy of adsorbed CO to determine surface sites in Fischer Tropsch catalysts. Use of in-situ analysis cells enables a detailed description of catalyst structure in reactive atmospheres and opens the possibility of correlating structure with catalytic activity. (author)

  5. Recent Technological Developments in Cobalt Catalysts for Fischer-Tropsch Synthesis

    Institute of Scientific and Technical Information of China (English)

    Junling Zhang; Jiangang Chen; Yongwang Li; Yuhan Sun

    2002-01-01

    Co-based catalysts are often utilized due to their high Fischer-Tropsch synthesis (FT) activity,C+5 hydrocarbon selectivity, low water-gas shift reaction (WGS) activity and relatively low cost. Selective control of C5+ hydrocarbons and the catalyst longevity are critical in the design of cobalt catalysts.Thus, various methods to improve the performance of Co catalysts have been suggested. The progress in cobalt catalysts reviewed in the last few decades, mainly involved the support, promoter, preparation and deactivation of Co-based catalysts.

  6. Processes on the "young" Mars: possible developments of events

    Science.gov (United States)

    Vidmachenko, A. P.

    2016-05-01

    Collected by Mars rovers and orbiters data allowed to reconstruct the possible stages in the development on the planet Mars. It is believed that the first geological era of the planet - Fillotsian - started 4.5 billion years ago. It lasted for 500-700 million years. At that time, Mars was a wet planet. Today Mars is a desert. However, when about 4 billion years ago there began an eruption of numerous volcanoes. The planet slowly cooled, volcanic activity has decreased - and ejection of gases into the atmosphere has decreased. Evidence of the impact of a large asteroid on Mars is the Hellas Planitia, which is located near the southern polar region. Thanks to the theory, methods of calculation and programs that are designed for tasks of penetration projectiles - managed to reconstruct the shape of Hellas and determine the parameters of asteroids. Upon impact, could have formed a powerful shock wave that has passed to the opposite hemisphere, and was focused symmetrically to the crater of Hellas. As a result by the shock wave was formed the highest volcano in Solar system - Olympus

  7. Acetylcholine synthesis and possible functions during sea urchin development

    Directory of Open Access Journals (Sweden)

    C Angelini

    2009-06-01

    Full Text Available Cholinergic neurotransmitter system molecules were found to play a role during fertilisation and early cell cycles of a large number of invertebrate and vertebrate organisms. In this study, we investigated the presence and possible function of choline acetyltransferase (ChAT, the biosynthetic enzyme of acetylcholine in gametes of the sea urchin, Paracentrotus lividus, through localisation and functional studies. ChAT-like molecules were detected in oocytes, mature eggs and zygotes with indirect immunofluorescence methods. Positive immunoreactivity was found in the ovarian egg cytoplasm and surface as well as at the zygote surface. This suggests the eggs' capacity to autonomously synthesise acetylcholine (ACh, the signal molecule of the cholinergic system. Acetylcholinesterase (AChE, the lytic enzyme of acetylcholine was also found in ovarian eggs, with a similar distribution; however, it disappeared after fertilisation. Ultrastructural ChAT localisation in sperms, which was carried out with the immuno-gold method, showed immunoreactivity in the acrosome of unreacted sperms and at the head surface of reacted sperms. In order to verify a functional role of ACh during fertilization and sea urchin development, in vivo experiments were performed. Exposure of the eggs before fertilisation to 1 mM ACh + 1 ?M eserine caused an incomplete membrane depolarisation and consequently enhanced polyspermy, while lower concentrations of ACh caused developmental anomalies. The exposure of zygotes to 0,045 AChE Units/mL of sea water caused developmental anomalies as well, in 50% of the embryos. Altogether, these findings and other previously obtained results, suggest that the cholinergic system may subserve two different tasks during development, according to which particular type of ACh receptor is active during each temporal window. The first function, taking place in the course of fertilisation is a result of autonomously synthesised ACh in sperms, while the

  8. Catalyst and process development for synthesis gas conversion to isobutylene. Final report, September 1, 1990--January 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Anthony, R.G.; Akgerman, A.

    1994-05-06

    Previous work on isosynthesis (conversion of synthesis gas to isobutane and isobutylene) was performed at very low conversions or extreme process conditions. The objectives of this research were (1) determine the optimum process conditions for isosynthesis; (2) determine the optimum catalyst preparation method and catalyst composition/properties for isosynthesis; (3) determine the kinetics for the best catalyst; (4) develop reactor models for trickle bed, slurry, and fixed bed reactors; and (5) simulate the performance of fixed bed trickle flow reactors, slurry flow reactors, and fixed bed gas phase reactors for isosynthesis. More improvement in catalyst activity and selectivity is needed before isosynthesis can become a commercially feasible (stand-alone) process. Catalysts prepared by the precipitation method show the most promise for future development as compared with those prepared hydrothermally, by calcining zirconyl nitrate, or by a modified sol-gel method. For current catalysts the high temperatures (>673 K) required for activity also cause the production of methane (because of thermodynamics). A catalyst with higher activity at lower temperatures would magnify the unique selectivity of zirconia for isobutylene. Perhaps with a more active catalyst and acidification, oxygenate production could be limited at lower temperatures. Pressures above 50 atm cause an undesirable shift in product distribution toward heavier hydrocarbons. A model was developed that can predict carbon monoxide conversion an product distribution. The rate equation for carbon monoxide conversion contains only a rate constant and an adsorption equilibrium constant. The product distribution was predicted using a simple ratio of the rate of CO conversion. This report is divided into Introduction, Experimental, and Results and Discussion sections.

  9. Large Scale Manufacture of Catalyst for Making DME Developed by Southwest Chemical Research and Design Institute

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The Southwest Chemical Research and Design Institute (SCRDI) after tackling the key technology related with the catalyst for manufacture of DME through gas phase dehydration of methanol has made great breakthroughs in large scale preparation of catalyst for DME production.

  10. Development of a CO2 Tolerant Fischer-Tropsch Catalyst:from Laboratory to Commercial-Scale Demonstration in Alaska

    Institute of Scientific and Technical Information of China (English)

    Joep J H M Font Freide; Tim D Gamlin; J Richard Hensman; Barry Nay; Christopher Sharp

    2004-01-01

    This article describes the development of BP's Fischer-Tropsch catalyst, used for the conversion of carbon monoxide and hydrogen into liquid hydrocarbons. It covers the 18 year period from the early eighties, when laboratory scale preparations and micro-reactors were heavily used, right through to the present day with the commercial scale manufacture and proving of the finished catalyst in BP's new $86 million gas to liquids demonstration facility in Nikiski, Alaska. Extensive performance testing and scale-up experiments have been successfully carried out, all proof that a laboratory preparation can indeed be translated into a commercial manufacturing process. In addition, the resulting catalyst does not only meet the process design targets, but also exhibits enhanced stability and is tolerant to carbon dioxide.Above all, a commercial scale, fixed bed Fischer-Tropsch catalyst is now available and ready for licensing.Manufacturing procedures and quality control have all been successfully detailed and transferred to the commercial manufacturer.

  11. Development status und future possibilities for martensitic creep resistant steels

    Energy Technology Data Exchange (ETDEWEB)

    Hald, J. [Technical Univ. Denmark, Lyngby (Denmark). Dept. of Mechanical Engineering

    2010-07-01

    In the last four decades new stronger modified 9%Cr martensitic creep resistant steels have been introduced in power plants, which has enabled increases in maximum achievable steam conditions from the previous 250 bar and 540-560 C up to the values of 300 bar and 600-620 C currently being introduced all over the world. In order to further increase the steam parameters of steel based power plants up to a target value of 650 C/325 bar it is necessary to double the creep strength of the martensitic steels. At the same time the resistance against steam oxidation must be improved by an increase of the chromium content in the steels from 9% to 12%. However, so far all attempts to make stronger 12%Cr steels have led to breakdowns in long-term creep strength. Significant progress has been achieved in the understanding of microstructure stability of the martensitic 9-12%Cr steels: Observed microstructure instabilities in 11-12%Cr steels are explained by Z-phase precipitation, which dissolves fine MN nitrides. Improved understanding of effects of B and N on long-term creep properties has formed the basis of a series of new stronger 9%Cr test alloys with improved creep strength. In parallel 9%Cr test steels with low C content show very promising behavior in long-term tests. However, the 9%Cr steels must be surface coated to protect against steam oxidation at high temperature applications above 620%C. A possibility to use fine Z-phases for strengthening of the martensitic steels has been identified, and this opens a new pathway for development of stable strong 12%Cr steels. There are still good prospects for the realization of a 325 bar / 650 C steam power plant all based on steel. (orig.)

  12. Novel growth method of carbon nanotubes using catalyst-support layer developed by alumina grit blasting.

    Science.gov (United States)

    Watanabe, Hiromichi; Ishii, Juntaro; Ota, Keishin

    2016-08-19

    We propose an efficient method of growing carbon nanotube (CNT) arrays on a variety of metals, alloys, and carbon materials using chemical vapor deposition (CVD) assisted by a simple surface treatment of the materials. The main feature of this method is the application of grit blasting with fine alumina particles to the development of a catalyst-support layer required for the growth of CNTs on various conductive materials, including ultra-hard metals such as tungsten. Auger electron spectroscopy shows that grit blasting can form a non-continuous layer where alumina nanoparticles are embedded as residues in the blasting media left on the treated surfaces. This work reveals that such a non-continuous alumina layer can behave as the catalyst-support layer, which is generally prepared by sputter or a vacuum evaporation coating process that considerably restricts the practical applications of CNTs. We have attempted to grow CNTs on grit-blasted substrates of eighteen conventionally used conductive materials using CVD together with a floating iron catalyst. The proposed method was successful in growing multi-walled CNT arrays on the grit-blasted surfaces of all the examined materials, demonstrating its versatility. Furthermore, we found that the group IV metal oxide films thermally grown on the as-received substrates can support the catalytic activity of iron nanoparticles in the CVD process just as well as the alumina film developed by grit blasting. Spectral emissivity of the CNT arrays in the visible and infrared wavelength ranges has been determined to assess the applicability of the CNT arrays as a black coating media.

  13. Novel growth method of carbon nanotubes using catalyst-support layer developed by alumina grit blasting

    Science.gov (United States)

    Watanabe, Hiromichi; Ishii, Juntaro; Ota, Keishin

    2016-08-01

    We propose an efficient method of growing carbon nanotube (CNT) arrays on a variety of metals, alloys, and carbon materials using chemical vapor deposition (CVD) assisted by a simple surface treatment of the materials. The main feature of this method is the application of grit blasting with fine alumina particles to the development of a catalyst-support layer required for the growth of CNTs on various conductive materials, including ultra-hard metals such as tungsten. Auger electron spectroscopy shows that grit blasting can form a non-continuous layer where alumina nanoparticles are embedded as residues in the blasting media left on the treated surfaces. This work reveals that such a non-continuous alumina layer can behave as the catalyst-support layer, which is generally prepared by sputter or a vacuum evaporation coating process that considerably restricts the practical applications of CNTs. We have attempted to grow CNTs on grit-blasted substrates of eighteen conventionally used conductive materials using CVD together with a floating iron catalyst. The proposed method was successful in growing multi-walled CNT arrays on the grit-blasted surfaces of all the examined materials, demonstrating its versatility. Furthermore, we found that the group IV metal oxide films thermally grown on the as-received substrates can support the catalytic activity of iron nanoparticles in the CVD process just as well as the alumina film developed by grit blasting. Spectral emissivity of the CNT arrays in the visible and infrared wavelength ranges has been determined to assess the applicability of the CNT arrays as a black coating media.

  14. DEVELOPMENT OF A NANO-Ni-La-Fe/Al2O3 CATALYST TO BE USED FOR SYN-GAS PRODUCTION AND TAR REMOVAL AFTER BIOMASS GASIFICATION

    Directory of Open Access Journals (Sweden)

    Jianfen Li

    2009-11-01

    Full Text Available The objective of this study was to develop a supported tri-metallic catalyst (nano-Ni-La-Fe/γ-Al2O3 for tar removal in biomass steam gasification, to significantly enhance the quality of the produced gas. For this purpose, the supported tri-metallic catalysts were prepared by a deposition-precipitation (DP method. Different analytical approaches were used to characterize the synthesized catalysts. The results showed that the prepared tri-metallic catalysts had an egg-shell structure with a specific surface area of 214.7 m2/g. The activity of the catalysts for gas production and tar removal in the process of biomass gasification was also investigated using a bench-scale combined fixed bed reactor. The experiments indicated that the tar yield after adding catalyst was reduced significantly and the efficiency of tar removal reached 99% for the biomass steam gasification at 800oC, while the gas yield after adding catalysts increased markedly and less coke was found over the catalyst. Meanwhile, the compositions of gas products before and after adding catalyst in the process also changed significantly; in particular, the content of hydrogen in catalytic steam gasification was improved by over 10 vol%. Therefore, using the prepared tri-metallic catalyst in biomass gasification can significantly improve the quality of the produced gas and efficiently eliminate the tar generation, preventing coke deposition on the catalyst surfaces, thus demonstrating a long lifetime of the catalyst.

  15. Manufacture of Catalyst Systems for Ammonia Conversion

    Institute of Scientific and Technical Information of China (English)

    GAKH S.V.; SAVENKOV D.A.

    2012-01-01

    Platinum catalyst gauzes have been in use since the moment of development of the process of catalyst oxidation of ammonia for production of nitric acid or hydrocyanic acid.Catalyst gauzes are usually made of platinum or its alloys with rhodium and palladium.These precious metals have remarkable properties that make them ideal catalysts for acceleration of the ammonia/oxygen reaction.In 2008,OJSC "SIC ‘Supermetal’" and Umicore AG&Co.KG launched a production line for Pt-alloy-based catalyst systems to be used for ammonia oxidation in the production of weak nitric acid.Catalyst systems consist of a pack of catalyst gauzes and a pack of catchment gauzes,which are made using flat-bed knitting machines and wire-cloth looms.Today,up-to-date catalyst systems MKSpreciseTM are being manufactured,the basic advantages of which are an individual structure of gauzes and composition of the material,which allows to define precisely the position of each gauze in the catalyst pack,a high activity of the catalyst pack,direct catching of platinum and rhodium in the catalyst system,and a reasonable combination of single- and multilayer types of gauzes.This makes it possible to vary the configuration of the catalyst and select an optimum composition of the system to ensure the maximum efficiency of the ammonia oxidation process.We also produce the catchment systems that allow to find the best decision from the economic point view for each individual case.

  16. Moral Development at the Crossroads: New Trends and Possible Futures

    Science.gov (United States)

    Lapsley, Daniel; Carlo, Gustavo

    2014-01-01

    This article introduces a special section on moral development. We claim that the field is now undergoing a resurgence of theoretical and methodological innovation after the eclipse of paradigmatic moral stage theory. Although research on prosocial development, moral emotions, and social domain theory has sustained interest in moral development,…

  17. Mechanism-guided development of VO(salen)X complexes as catalysts for the asymmetric synthesis of cyanohydrin trimethylsilyl ethers.

    Science.gov (United States)

    Belokon, Yuri N; Clegg, William; Harrington, Ross W; Maleev, Victor I; North, Michael; Pujol, Marta Omedes; Usanov, Dmitry L; Young, Carl

    2009-01-01

    Catalyze this! Detailed study of the mechanism of asymmetric cyanohydrin synthesis catalyzed by VO(salen)X complexes (see figure) led to the development of VO(salen)NCS, as the most active vanadium-based catalyst yet developed for this reaction.The mechanism by which oxovanadium(V)(salen) complexes(1) VO(salen)X catalyze the asymmetric addition of trimethylsilyl cyanide to benzaldehyde has been studied. The reaction kinetics indicated that the structure of the counterion (X) had a significant influence on the rate, but not on the enantioselectivity of the reaction. The less coordinating the counterion, the lower the catalytic activity; a trend that was confirmed by a Hammett analysis. Variable temperature kinetics allowed the enthalpies and entropies of activation to be determined for some catalysts, and showed that, for others, the overall reaction order changes from second order to zero order as the temperature is reduced. The order with respect to the catalyst was determined for nine of the VO(salen)X complexes and showed that the less active catalysts were active predominantly as mononuclear species whilst the more active catalysts were active predominantly as dinuclear species. Mass spectrometry confirmed the formation of dinuclear species in situ from all of the VO(salen)X complexes and indicated that the dinuclear complexes contained one vanadium(V) and one vanadium(IV) ion. The latter conclusion was supported by cyclic voltammetry of the complexes, by fluorescence measurements and by the fact that catalyst deactivation occurs when reactions are carried out under an inert atmosphere. Based on this evidence, it has been deduced that the catalysis involves two catalytic cycles: one for catalysis by mononuclear VO(salen)X species and the other for catalysis by dinuclear species. The catalytic cycle involving dinuclear species involves activation of both the cyanide and aldehyde, whereas the catalytic cycle involving mononuclear species activates only the

  18. The possible effect of diazepam on cancer development and growth.

    Science.gov (United States)

    Horrobin, D F; Trosko, J E

    1981-01-01

    Diazepam has the characteristics of a tumour promoter in a number of in vitro systems. The effect is apparent at concentrations of diazepam which are clinically relevant. Diazepam also accelerated tumour growth in two different experimental animal cancers. Tranquillizer use was found to be greater in women with metastatic breast cancer at the time of diagnosis than in those without metastases. Further evaluation of the possible effects of diazepam and related drugs on human and animal cancers is urgently required.

  19. Development of vanadium-phosphate catalysts for methanol production by selective oxidation of methane

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, R.L. [Colorado School of Mines, Golden, CO (United States)

    1995-12-31

    The United States has vast natural gas reserves which could contribute significantly to our energy security if economical technologies for conversion to liquid fuels and chemicals were developed. Many of these reserves are small scale or in remote locations and of little value unless they can be transported to consumers. Transportation is economically performed via pipeline, but this route is usually unavailable in remote locations. Another option is to convert the methane in the gas to liquid hydrocarbons, such as methanol, which can easily and economically be transported by truck. Therefore, the conversion of methane to liquid hydrocarbons has the potential to decrease our dependence upon oil imports by opening new markets for natural gas and increasing its use in the transportation and chemical sectors of the economy. In this project, we are attempting to develop, and explore new catalysts capable of direct oxidation of methane to methanol. The specific objectives of this work are discussed.

  20. Modern multiphase catalysis: new developments in the separation of homogeneous catalysts.

    Science.gov (United States)

    Muldoon, Mark J

    2010-01-14

    Homogeneous catalysts are powerful tools for the synthesis of fine chemicals, pharmaceuticals and materials, however their exploitation on an industrial scale is often held back due to the challenges of separating and recycling the catalyst. This perspective focuses on approaches to multiphase catalysis that have emerged in the last decade, highlighting methods that can address the separation issues and in some cases result in superior catalyst performance and environmental benefits.

  1. Moldova Power Sources Development including Nuclear Power Plant possible participation

    Directory of Open Access Journals (Sweden)

    Comendant

    2007-12-01

    Full Text Available For the new power market conditions Moldova power sources development options up to 2030 are evaluated, attempting to propose the best solutions in this respect and the ways they be realized.

  2. Possible Challenges of Teacher Research for Teacher Professional Development

    OpenAIRE

    2016-01-01

    Teacher research (i.e. action research) has gained acceptance as a tool for teacher professional development. In spite of its increasing popularity in language classrooms, concerns have been raised in the implementation of teacher research, such as issues of quality, sustainability, the development of standards, and accessibility. In the Indonesian context, the unprofessional working conditions and the education background of most teachers have made it difficult for teachers to sustain and ac...

  3. Enantioselective Decarboxylative Alkylation Reactions: Catalyst Development, Substrate Scope, and Mechanistic Studies

    KAUST Repository

    Behenna, Douglas C.

    2011-11-14

    α-Quaternary ketones are accessed through novel enantioselective alkylations of allyl and propargyl electrophiles by unstabilized prochiral enolate nucleophiles in the presence of palladium complexes with various phosphinooxazoline (PHOX) ligands. Excellent yields and high enantiomeric excesses are obtained from three classes of enolate precursor: enol carbonates, enol silanes, and racemic β-ketoesters. Each of these substrate classes functions with nearly identical efficiency in terms of yield and enantioselectivity. Catalyst discovery and development, the optimization of reaction conditions, the exploration of reaction scope, and applications in target-directed synthesis are reported. Experimental observations suggest that these alkylation reactions occur through an unusual inner-sphere mechanism involving binding of the prochiral enolate nucleophile directly to the palladium center.

  4. Development and Electrochemical Studies of Ruthenium Based Mixed Oxide Catalyst Electrodes for Chlorine Evolution

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Experimental results are presented which allow comparison of the electrochemical performance of RuO2/Ti, Ru0.3Sn0.7O2/Ti and Ru0.3V0.7O2/Ti catalysts prepared on a titanium substrate by thermal decomposition from respective precursors. The highest activity for chlorine evolution is observed on the Ru0.3V0.7O2/Ti electrode, lower on Ru0.3Sn0.7O2/Ti and least on RuO2/Ti. Voltammograms obtained in the polarisable region are used to characterize the different electrodes. Further more an analysis of the catalytic activity and reaction kinetics of the developed electrodes in NaCl are presented.

  5. Possible Challenges of Teacher Research for Teacher Professional Development

    Directory of Open Access Journals (Sweden)

    Utami Widiati

    2016-02-01

    Full Text Available Teacher research (i.e. action research has gained acceptance as a tool for teacher professional development. In spite of its increasing popularity in language classrooms, concerns have been raised in the implementation of teacher research, such as issues of quality, sustainability, the development of standards, and accessibility. In the Indonesian context, the unprofessional working conditions and the education background of most teachers have made it difficult for teachers to sustain and access research. Since changing the former appears beyond the aim of this article, it is suggested that teacher education institutions focus on the latter, revisiting the curriculum of teacher education to provide more research components

  6. Possible Effects of Internet Use on Cognitive Development in Adolescence

    Directory of Open Access Journals (Sweden)

    Kathryn L. Mills

    2016-06-01

    Full Text Available The rise of digital media use and the ability to be in almost constant connection to the Internet has raised a number of concerns about how Internet use could impact cognitive abilities. In particular, parents and policy makers are concerned with how being ‘constantly online’ might disrupt social and cognitive development. This review integrates the latest empirical evidence on Internet use with relevant experimental studies to discuss how online behaviors, and the structure of the online environment, might affect the cognitive development of adolescents. Popular concerns are discussed in light of the reviewed evidence, and remaining gaps in knowledge are highlighted.

  7. Development of stable influenza vaccine powder formulations: challenges and possibilities.

    Science.gov (United States)

    Amorij, J-P; Huckriede, A; Wilschut, J; Frijlink, H W; Hinrichs, W L J

    2008-06-01

    Influenza vaccination represents the cornerstone of influenza prevention. However, today all influenza vaccines are formulated as liquids that are unstable at ambient temperatures and have to be stored and distributed under refrigeration. In order to stabilize influenza vaccines, they can be brought into the dry state using suitable excipients, stabilizers and drying processes. The resulting stable influenza vaccine powder is independent of cold-chain facilities. This can be attractive for the integration of the vaccine logistics with general drug distribution in Western as well as developing countries. In addition, a stockpile of stable vaccine formulations of potential vaccines against pandemic viruses can provide an immediate availability and simple distribution of vaccine in a pandemic outbreak. Finally, in the development of new needle-free dosage forms, dry and stable influenza vaccine powder formulations can facilitate new or improved targeting strategies for the vaccine compound. This review represents the current status of dry stable inactivated influenza vaccine development. Attention is given to the different influenza vaccine types (i.e. whole inactivated virus, split, subunit or virosomal vaccine), the rationale and need for stabilized influenza vaccines, drying methods by which influenza vaccines can be stabilized (i.e. lyophilization, spray drying, spray-freeze drying, vacuum drying or supercritical fluid drying), the current status of dry influenza vaccine development and the challenges for ultimate market introduction of a stable and effective dry-powder influenza vaccine.

  8. Electric bicycles in The Netherlands: Current developments and future possibilities

    NARCIS (Netherlands)

    Rooijen, T. van

    2010-01-01

    Developments with electric bicycles in the Netherlands are progressing rapidly. The number of electric bicycles sold is rises every year. Cycling is a very popular mode of transport in The Netherlands. In 2008 more than one million bicycles were sold. At the moment one out of ten bicycles sold is al

  9. Using Evidence to Encourage Inclusive School Development: Possibilities and Challenges

    Science.gov (United States)

    Ainscow, Mel; Kaplan, Ian

    2005-01-01

    Recent research suggests that inquiry-based approaches can be powerful in stimulating the development of inclusive practices. However, the implementation of such approaches can be difficult, particularly in contexts where there is a strong emphasis on improving standards, as measured by test and examination scores. This article describes and…

  10. Environmental exposure scenarios: development, challenges and possible solutions.

    Science.gov (United States)

    Ahrens, Andreas; Traas, Theo P

    2007-12-01

    Under the new REACH system, companies importing, producing and marketing chemical substances will be obliged to register the single substances and to carry out a safety assessment for all identified uses during the life cycle of the substance. This duty will apply to about 10,000 existing substances in the EU market exceeding an annual production or import volume of 10 t per company. If the substance is already known to be dangerous or turns out to be dangerous(1) during the hazard assessment, the registrant is obliged to carry out an exposure assessment and a risk characterisation for all identified uses. The goal of the safety assessment is to define the conditions of use that allow for adequate control of risk with regard to health and safety at the work place, consumer safety and protection of the environment. Once the registrant has established and documented these conditions in the Chemicals Safety Report (CSR), that information is to be communicated down the supply chain by means of the Extended Safety Data Sheet (eSDS). The ultimate aim of the new legislation is to establish duties and mechanisms that systematically prevent or limit exposure to dangerous industrial chemicals. The current paper explains this concept with regard to environmental exposure and highlights the challenges and possible solutions.

  11. Information Support of Regions and Possibilities of Its Further Development

    Directory of Open Access Journals (Sweden)

    J. Vaněk, M. Stočes, P. Šimek, I. Hrbek

    2012-09-01

    Full Text Available The paper presents the results of information and communication technologies (ICT research support in the Czech Republic regions, focused mainly on the problems of mapping cultural heritage together with activities in the area of tourism and business activities connected with it (accommodation, food etc. One possible approach is demonstrated on the example of web portal “Get to know Posumavi – a tourist guide to Posumavi”. This approach integrates the advantages of standard information sources with the Internet application. Moreover, this application provides a clear topographical output. The project is being prepared in co-operation with a chosen local partner, in our case the Posumavi local action group. The under-mentioned solution can be further extended if need be, but we can also understand it as a general-purpose solution which means it can be widely used in other areas of the information support of regions.The knowledge and data presented in the paper were obtained as a result of the Research Program titled “Economy of the Czech Agriculture Resources and Their Efficient Use within the Framework of the Multifunctional Agri-food Systems” of the Czech Ministry of Education, Youth and Sports number VZ MSM 6046070906.

  12. Development of molecular and solid catalysts for the direct low-temperature oxidation of methane to methanol.

    Science.gov (United States)

    Palkovits, Regina; von Malotki, Christian; Baumgarten, Martin; Müllen, Klaus; Baltes, Christian; Antonietti, Markus; Kuhn, Pierre; Weber, Jens; Thomas, Arne; Schüth, Ferdi

    2010-02-22

    The direct low-temperature oxidation of methane to methanol is demonstrated on a highly active homogeneous molecular catalyst system and on heterogeneous molecular catalysts based on polymeric materials possessing ligand motifs within the material structure. The N-(2-methylpropyl)-4,5-diazacarbazolyl-dichloro-platinum(II) complex reaches significantly higher activity compared to the well-known Periana system and allows first conclusions on electronic and structural requirements for high catalytic activity in this reaction. Interestingly, comparable activities could be achieved utilizing a platinum modified poly(benzimidazole) material, which demonstrates for the first time a solid catalyst with superior activity compared to the Periana system. Although the material shows platinum leaching, improved activity and altered electronic properties, compared to the conventional Periana system, support the proposed conclusions on structure-activity relationships. In comparison, platinum modified triazine-based catalysts show lower catalytic activity, but rather stable platinum coordination even after several catalytic cycles. Based on these systems, further development of improved solid catalysts for the direct low-temperature oxidation of methane to methanol is feasible.

  13. Oxidation catalyst

    Science.gov (United States)

    Ceyer, Sylvia T.; Lahr, David L.

    2010-11-09

    The present invention generally relates to catalyst systems and methods for oxidation of carbon monoxide. The invention involves catalyst compositions which may be advantageously altered by, for example, modification of the catalyst surface to enhance catalyst performance. Catalyst systems of the present invention may be capable of performing the oxidation of carbon monoxide at relatively lower temperatures (e.g., 200 K and below) and at relatively higher reaction rates than known catalysts. Additionally, catalyst systems disclosed herein may be substantially lower in cost than current commercial catalysts. Such catalyst systems may be useful in, for example, catalytic converters, fuel cells, sensors, and the like.

  14. Exploring the Possibilities of Developing Sport Tourism in Linzi

    OpenAIRE

    2009-01-01

    Though the concept of sport tourism has been applied to various products and services in a number of destinations, such as the USA and the UK, it is still a relatively new area for China tourism market. Sport tourism destination researches are mainly based on western countries with advanced developed competing sport industry and history and the feasibility of sport tourism based on a destination with cultural heritage sport resource has not well explored. This paper has two aims to achieve. F...

  15. MANAGEMENT AND DEVELOPMENT POSSIBILITIES FOR SPA TOURISM IN SERBIA

    Directory of Open Access Journals (Sweden)

    Milijana ĐORĐEVIĆ

    2010-06-01

    Full Text Available Two forms of tourism, which are represented to a large extent in the world, are spa and wellness tourism. In Serbia, spa and wellness tourism are not sufficiently used, although there are excellent conditions. During twenty century the state was paying more attention and money on the sea and river tourism. However, the separation of Serbia and Montenegro in two independent counties had left Serbia without an entrance to the Adriatic Sea, so development of other tourist products and destinations became an imperative for survival and existence in the tourist map of Europe and the world. The paper presents the basic aims and policies of development of spa tourism in Serbia and data obtained in the survey regarding quality of services provided in some spa towns in Serbia. Based on the results to which the research occurred, authors wished to point out main activities and tasks that the state uses in creating a development strategy of spa tourism, the programs that have already been taken, so as the influence of the economic crisis to spa tourism.

  16. Polyamine levels and tomato fruit development: possible interaction with ethylene.

    Science.gov (United States)

    Saftner, R A; Baldi, B G

    1990-02-01

    Fruits of tomato, Lycopersicon esculentum Mill. cv Liberty, ripen slowly and have a prolonged keeping quality. Ethylene production and the levels of polyamines in pericarp of cv Liberty, Pik Red, and Rutgers were measured in relation to fruit development. Depending on the stage of fruit development, Liberty produced between 16 and 38% of the ethylene produced by Pik Red and Rutgers. The polyamines putrescine, spermidine, and spermine were present in all cultivars. Cadaverine was detected only in Rutgers. Levels of putrescine and spermidine declined between the immature and mature green stages of development and prior to the onset of climacteric ethylene production. In Pik Red and Rutgers, the decline persisted, whereas in Liberty, the putrescine level increased during ripening. Ripe pericarp of Liberty contained about three and six times more free (unconjugated) polyamines than Pik Red and Rutgers, respectively. No pronounced changes in spermidine or cadaverine occurred during ripening. The increase in the free polyamine level in ripe pericarp of Liberty may account for the reduction of climacteric ethylene production, and prolonged storage life.

  17. TRENDS IN OFFICIAL DEVELOPMENT ASSISTANCE TO DEVELOPING COUNTRIES AND POSSIBILITIES OF ALTERNATIVE FINANCING MECHANISMS

    Directory of Open Access Journals (Sweden)

    Talknice Saungweme

    2013-09-01

    Full Text Available The study analyses trends in Official Development Assistance (ODA to developing countries, mainly Africa, and possibilities of new financing instruments. Economies of most developing countries, especially those in Sub-Saharan Africa, are characterised by low investment flows, huge import bills and lower exports. Subsequently, development assistance is the major source of external finance and has taken the form of budget support, humanitarian and development finance. However, the noted fall in ODA in 2005, 2009 and 2012 might adversely impact directly on the attainment of millennium development goals in 2015. This negative trend in ODA is a result of a combination of factors such as economic constraints in the donor countries (for example, the debt crisis and/or a new shift in financing mechanisms to developing countries.

  18. Design strategies for development of SCR catalyst: improvement of alkali poisoning resistance and novel regeneration method.

    Science.gov (United States)

    Peng, Yue; Li, Junhua; Shi, Wenbo; Xu, Jiayu; Hao, Jiming

    2012-11-20

    Based on the ideas of the additives modification and regeneration method update, two different strategies were designed to deal with the traditional SCR catalyst poisoned by alkali metals. First, ceria doping on the V(2)O(5)-WO(3)/TiO(2) catalyst could promote the SCR performance even reducing the V loading, which resulted in the enhancement of the catalyst's alkali poisoning resistance. Then, a novel method, electrophoresis treatment, was employed to regenerate the alkali poisoned V(2)O(5)-WO(3)/TiO(2) catalyst. This novel technique could dramatically enhance the SCR activities of the alkali poisoned catalysts by removing approximately 95% K or Na ions from the catalyst and showed less hazardous to the environment. Finally, the deactivation mechanisms by the alkali metals were extensively studied by employing both the experimental and DFT theoretical approaches. Alkali atom mainly influences the active site V species rather than W oxides. The decrease of catalyst surface acidity might directly reduce the catalytic activity, while the reducibility of catalysts could be another important factor.

  19. The Possibilities of Using Organization Development Technologies in Thai Culture.

    Science.gov (United States)

    1983-03-01

    has been the main dri--ving force in Thai cultural development. Ilach of cl.assical Thai art., particularly architecture, cultura , painting and =arly...progress upward in a public institutiLon, t:he executivqs mus-t indicate a zolding, of attitudes to fit -he particular agency affiliation. Whilst this...curricula are fitted to ci-vi-l service exazination. Possessi-or. of -he hachrelcZ’s degree is reauired for entrance t.o the ssrvics as a thi6r d grade

  20. Oxytocin during development: possible organizational effects on behavior

    Directory of Open Access Journals (Sweden)

    Heather K Caldwell

    2015-05-01

    Full Text Available Oxytocin (Oxt is a neurohormone known for its physiological roles associated with lactation and parturition in mammals. Oxt can also profoundly influence mammalian social behaviors such as affiliative, parental, and aggressive behaviors. While the acute effects of Oxt signaling on adult behavior have been heavily researched in many species, including humans, the developmental effects of Oxt on the brain and behavior is just beginning to be explored. There is evidence that Oxt in early postnatal and peripubertal development, and perhaps during prenatal life, affects adult behavior by altering neural structure and function. However, the specific mechanisms by which this occurs remain unknown. Thus, this review will detail what is known about how developmental Oxt impacts behavior as well as specific neurochemicals and neural substrates that are important to these behaviors.

  1. Developing a standardized cephalometric vocabulary: choices and possible strategies.

    Science.gov (United States)

    Stewart, Randall F; Edgar, Heather; Tatlock, Charles; Kroth, Philip J

    2008-09-01

    The science of cephalometry has been invaluable for guiding orthodontic diagnosis, treatment planning, and outcomes tracking. Though software packages easily calculate most cephalometric measurements, the ability to exchange cephalometric data between software packages is poorly developed. Hindering this effort is the lack of an agreed-upon standard for electronic exchange of cephalometric measurements. Unlike more technological issues, the problem of creating such a standard is one of formalizing decisions already established through historical precedent. Solving this problem will require education, cooperation, and consensus in order to reap the potential improvements to patient care, dental education, and research. The first step in overcoming these remaining issues is awareness. This article reviews those factors that place cephalometric measurements in an excellent position for standardization, outlines those decisions that must be made in order to realize the goal of electronic exchange of cephalometric information, and describes some of the options for these decisions as well as some advantages and disadvantages of each.

  2. Possibilities and challenges for developing a successful vaccine for leishmaniasis.

    Science.gov (United States)

    Srivastava, Saumya; Shankar, Prem; Mishra, Jyotsna; Singh, Sarman

    2016-05-12

    Leishmaniasis is a vector-borne disease caused by different species of protozoan parasites of the genus Leishmania. It is a major health problem yet neglected tropical diseases, with approximately 350 million people worldwide at risk and more than 1.5 million infections occurring each year. Leishmaniasis has different clinical manifestations, including visceral (VL or kala-azar), cutaneous (CL), mucocutaneous (MCL), diffuse cutaneous (DCL) and post kala-azar dermal leishmaniasis (PKDL). Currently, the only mean to treat and control leishmaniasis is by rational medications and vector control. However, the number of available drugs is limited and even these are either exorbitantly priced, have toxic side effects or prove ineffective due to the emergence of resistant strains. On the other hand, the vector control methods are not so efficient. Therefore, there is an urgent need for developing a safe, effective, and affordable vaccine for the prevention of leishmaniasis. Although in recent years a large body of researchers has concentrated their efforts on this issue, yet only three vaccine candidates have gone for clinical trial, until date. These are: (i) killed vaccine in Brazil for human immunotherapy; (ii) live attenuated vaccine for humans in Uzbekistan; and (iii) second-generation vaccine for dog prophylaxis in Brazil. Nevertheless, there are at least half a dozen vaccine candidates in the pipeline. One can expect that, in the near future, the understanding of the whole genome of Leishmania spp. will expand the vaccine discovery and strategies that may provide novel vaccines. The present review focuses on the development and the status of various vaccines and potential vaccine candidates against leishmaniasis.

  3. Consumer exposure scenarios: development, challenges and possible solutions.

    Science.gov (United States)

    Van Engelen, J G M; Heinemeyer, G; Rodriguez, C

    2007-12-01

    Exposure scenarios (ES) under REACH (Registration, Evaluation, and Authorisation of Chemicals; new EU legislation) aim to describe safe conditions of product and substance use. Both operational conditions and risk management measures (RMMs) are part of the ES. For consumer use of chemicals, one of the challenges will be to identify all of the consumer uses of a given chemical and then quantify the exposure derived from each of them. Product use categories can be established to identify in a systematic fashion how products are used. These product categories comprise products that are used similarly (e.g. paints, adhesives). They deliver information about product use characteristics, and provide an easy-to-handle tool for exchanging standardised information. For practical reasons, broad ES will have to be developed, which cover a wide range of products and use. The challenge will be to define them broadly, but not in a way that they provide such an overestimation of exposure that a next iteration or a more complex model is always needed. Tiered and targeted approaches for estimation of exposure at the right level of detail may offer the best solution. RMMs relevant for consumers include those inherent to product design (controllable) and those that are communicated to consumers as directions for use (non-controllable). Quantification of the effect of non-controllable RMMs on consumer exposure can prove to be difficult. REACH requires aggregation of exposure from all relevant identified sources. Development of appropriate methodology for realistic aggregation of exposure will be no small challenge and will likely require probabilistic approaches and comprehensive databases on populations' habits, practices and behaviours. REACH regulation aims at controlling the use of chemicals so that exposure to every chemical can be demonstrated to be safe for consumers, workers, and the environment when considered separately, but also when considered in an integrated way. This

  4. Development of a Practical Hydrogen Storage System Based on Liquid Organic Hydrogen Carriers and a Homogeneous Catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Craig [Hawaii Hydrogen Carriers, LLC, Honolulu, HI (United States); Brayton, Daniel [Hawaii Hydrogen Carriers, LLC, Honolulu, HI (United States); Jorgensen, Scott W. [General Motors, LLC, Warren, MI (United States). Research and Development Center. Chemical and Material Systems Lab.; Hou, Peter [General Motors, LLC, Warren, MI (United States). Research and Development Center. Chemical and Material Systems Lab.

    2017-03-24

    The objectives of this project were: 1) optimize a hydrogen storage media based on LOC/homogeneous pincer catalyst (carried out at Hawaii Hydrogen Carriers, LLC) and 2) develop space, mass and energy efficient tank and reactor system to house and release hydrogen from the media (carried out at General Motor Research Center).

  5. Possibilities to develop low-fat products: a review

    Directory of Open Access Journals (Sweden)

    Tufeanu Roxana

    2016-06-01

    Full Text Available Research has proved a relationship between high fat consumption and rise in obesity, atherosclerosis, coronary heart diseases and high blood pressure. Therefore is recommended the moderate consumption of fat, such that the total fat does not exceed 30% of total energy intake. Our body needs fats because are providers of calories, essential fatty acids, fat-soluble vitamins and also they are necessary ingredients of the foods. The development of products with low-fat content can be considerate a challenge because the lipids offers aroma, texture, appearance, flavour and mouth feel, qualities that customers want in food products. A fat reduction can be achieved by using different fat replacers to ensure the functionality of the replaced fat. Functional components of fat replacers can have a significant role in promotion of wellbeing, in treating and preventing diseases. Thus, fat replacers should be recognized as safe and healthy, which have sensorial and functional properties. This paper reviews the fat replacers used to obtain foods as meat-based or dairy products. Some ways to obtain healthier meat products by reducing saturated fats content consist in the utilization of unsaturated vegetable oils, vegetable products, fibre. The utilization of fibre in products such bolognas, sausages or hamburgers, can improve the texture profile, binding properties and the characteristics regarding the cooking process. A fat reduction in dairy products can be achieved by replacing it with starches, polysaccharides, gums or fibres from cereal, vegetables and fruits. In acidified milk products, fibres have benefits as: low syneresis, sensory characteristics accepted by consumers, improvement of texture and rheological properties. In cheeses production, the fat reduction can be realised by replacing it with carbohydrate or protein-based replacers in order to obtain a final product with proper characteristics.

  6. Magnetic catalyst bodies

    NARCIS (Netherlands)

    Teunissen, Wendy; Bol, A.A.; Geus, John W.

    2001-01-01

    After a discussion about the importance of the size of the catalyst bodies with reactions in the liquid-phase with a suspended catalyst, the possibilities of magnetic separation are dealt with. Deficiencies of the usual ferromagnetic particles are the reactivity and the clustering of the particles.

  7. Photocatalytic hydrogen production on SOLECTRO {sup registered} titanium dioxide layers. Development and characterization of an efficient catalyst; Photokatalytische Wasserstoffgewinnung an SOLECTRO {sup registered} -Titandioxidschichten. Entwicklung und Charakterisierung eines geeigneten Katalysators

    Energy Technology Data Exchange (ETDEWEB)

    Saborowski, Sarah

    2010-03-03

    A catalyst for photocatalytic hydrogen production from methanol and water was developed on the basis of SOLECTRO {sup registered} titanium dioxide layers. A test facility was constructed in which several modified catalysts could be tested for this reaction. Detailed characterization of the electronic and optical characteristics of these catalysts made it possible to gain deeper insight into the processes involved in the reaction. (orig.) [German] Auf Basis der SOLECTRO {sup registered} -TiO{sub 2} -Schichten wurde ein Katalysator fuer die photokatalytische Wasserstoffdarstellung aus Methanol und Wasser entwickelt. Der Aufbau einer geeigneten Versuchsanlage ermoeglichte es, verschieden modifizierte Katalysatoren fuer diese Reaktion zu testen. Durch die ausfuehrliche Charakterisierung insbesondere der elektronischen und optischen Eigenschaften dieser Katalysatoren konnten vertiefende Erkenntnisse zu den waehrend der Reaktion ablaufenden Prozessen gewonnen werden. (orig.)

  8. Impeded solid state reactions and transformations in ceramic catalysts supports and catalysts

    Directory of Open Access Journals (Sweden)

    Ernő E. Kiss

    2012-12-01

    Full Text Available Impeded chemical reactions and impeded polymorphous transformation in materials are discussed, as desired effects, for stabilization of ceramic catalyst supports and ceramic based catalysts. This paper gives a short overview about the possibilities of slowing down the aging processes in ceramic catalyst supports and catalysts. Special attention is given to alumina and titania based catalysts.

  9. Development of Highly Effective Nanoparticle Spinel Catalysts for Aerobic Oxidation of Benzylic Alcohols

    Institute of Scientific and Technical Information of China (English)

    JI,Hong-Bing(纪红兵); WANG,Le-Fu(王乐夫)

    2002-01-01

    Spinel catalyst MnFe1.8Cu0.15Ru0.05O4 with particle size of about 42 nm is an effective heterogeneous catalyst for the oxidation of benzylic alcohols. The substitution of Fe for Cu improves its catalytic activity. Based on the characterization of BET, XPS and EXAFS, two factors influencing the structure and texture of the catalyst caused by the substitution of Cu for Fe may be assumed: physical factor responsible for the increasing of surface area; chemical factor responsible for the transformation of Ru-O bonds to Ru = O bonds. β-Elimination is considered to be an important step in the reaction.

  10. New catalyst developed at Argonne National Laboratory could help diesels meet NOx deadlines

    CERN Document Server

    2003-01-01

    "A new catalyst could help auto makers meet the U.S. Environmental Protection Agency's deadline to eliminate 95 percent of nitrogen-oxide from diesel engine exhausts by 2007, while saving energy" (1 page).

  11. ANALYSIS AND DEVELOPMENT OF COPPER RECYCLING OF DEAD COPPER-CONTAINING CATALYSTS

    OpenAIRE

    O. S. Komarov; I. V. Provorova; V. I. Volosatikov; D. O. Komarov; N. I. Urbanovich

    2009-01-01

    The technology of processing of copper-bearing dead catalysts, which includes leaching and deposition of copper by means of electrolysis and also their application in composition of the mixture for alloy doping is offered.

  12. ANALYSIS AND DEVELOPMENT OF COPPER RECYCLING OF DEAD COPPER-CONTAINING CATALYSTS

    Directory of Open Access Journals (Sweden)

    O. S. Komarov

    2009-01-01

    Full Text Available The technology of processing of copper-bearing dead catalysts, which includes leaching and deposition of copper by means of electrolysis and also their application in composition of the mixture for alloy doping is offered.

  13. Brief Communication: CATALYST - a multi-regional stakeholder Think Tank for fostering capacity development in disaster risk reduction and climate change adaptation

    NARCIS (Netherlands)

    Terwisscha van Scheltinga, C.T.H.M.; Hare, M.P.; Bers, van C.; Keur, van der P.

    2014-01-01

    This brief communication presents the work and objectives of the CATALYST project on "Capacity Development for Hazard Risk Reduction and Adaptation" funded by the European Commission (October 2011–September 2013). CATALYST set up a multi-regional think tank covering four regions (Central America and

  14. Development of biomimetic catalytic oxidation methods and non-salt methods using transition metal-based acid and base ambiphilic catalysts.

    Science.gov (United States)

    Murahashi, Shun-Ichi

    2011-01-01

    This review focuses on the development of ruthenium and flavin catalysts for environmentally benign oxidation reactions based on mimicking the functions of cytochrome P-450 and flavoenzymes, and low valent transition-metal catalysts that replace conventional acids and bases. Several new concepts and new types of catalytic reactions based on these concepts are described. (Communicated by Ryoji Noyori, M.J.A.).

  15. Development of vanadium-phosphate catalysts for methanol production by selective oxidation of methane. Quarterly technical progress report 10, July 1, 1995--September 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, R.L.

    1995-12-07

    This document is the tenth quarterly technical progress report under Contract No. DE-AC22-92PC92110 {open_quotes}Development of Vanadium-Phosphate Catalysts for Methanol Production by Selective Oxidation of Methane{close_quotes}. Activities focused on testing of additional modified and promoted catalysts and characterization of these materials. Attempts at improving the sensitivity of our GC based analytical systems were also made with some success. Methanol oxidation studies were initiated. These results are reported. Specific accomplishments include: (1) Methane oxidation testing of a suite of catalysts promoted with most of the first row transition metals was completed. Several of these materials produced low, difficult to quantify yields of formaldehyde. (2) Characterization of these materials by XRD and FTIR was performed with the goal of correlating activity and selectivity with catalyst properties. (3) We began to characterize catalysts prepared via modified synthesis methods designed to enhance acidity using TGA measurements of acetonitrile chemisorption and methanol dehydration to dimethyl ether as a test reaction. (4) A catalyst prepared in the presence of naphthalene methanol as a structural disrupter was tested for activity in methane oxidation. It was found that this material produced low yields of formaldehyde which were difficult to quantify. (5) Preparation of catalysts with no Bronsted acid sites. This was accomplished by replacement of exchangeable protons with potassium, and (6) Methanol oxidation studies were initiated to provide an indication of catalyst activity for decomposition of this desired product and as a method of characterizing the catalyst surface.

  16. Performance Comparison of Two Newly Developed Bimetallic (X-Mo/Al2O3, X=Fe or Co) Catalysts for Reverse Water Gas Shift Reaction

    Institute of Scientific and Technical Information of China (English)

    Abolfazl Gharibi Kharaji; Ahmad Shariati

    2016-01-01

    The performance of the two newly developed bimetallic catalysts based on the precursor, Mo/Al2O3, was com-pared for reverse water gas shift (RWGS) reaction. The structures of the precursor and the catalysts were studied using X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) analysis, inductively coupled plasma-atomic emission spec-trometry (ICP-AES), CO chemisorption, temperature programmed reduction of hydrogen (H2-TPR) and scanning electron microscopy (SEM) techniques. The activity of Fe-Mo and Co-Mo catalysts was compared in a ifxed bed reactor at different temperatures. It is shown that the Co-Mo catalyst has higher CO2 conversion at all temperature level. The time-on-stream (TOS) analysis of the activity of catalysts for the RWGS reaction was carried out over a continuous period of 60 h for both catalysts. The Fe-Mo/Al2O3 catalyst exhibits good stability within a period of 60 h, however, the Co-Mo/Al2O3 is gradually deactivated after 50 h of reaction time. Existence of Fe2(MoO4)3 phase in Fe-Mo/Al2O3 catalyst makes this catalyst more stable for RWGS reaction.

  17. Catalyst Alloys Processing

    Science.gov (United States)

    Tan, Xincai

    2014-10-01

    Catalysts are one of the key materials used for diamond formation at high pressures. Several such catalyst products have been developed and applied in China and around the world. The catalyst alloy most widely used in China is Ni70Mn25Co5 developed at Changsha Research Institute of Mining and Metallurgy. In this article, detailed techniques for manufacturing such a typical catalyst alloy will be reviewed. The characteristics of the alloy will be described. Detailed processing of the alloy will be presented, including remelting and casting, hot rolling, annealing, surface treatment, cold rolling, blanking, finishing, packaging, and waste treatment. An example use of the catalyst alloy will also be given. Industrial experience shows that for the catalyst alloy products, a vacuum induction remelt furnace can be used for remelting, a metal mold can be used for casting, hot and cold rolling can be used for forming, and acid pickling can be used for metal surface cleaning.

  18. Visible-Light-Responsive Photocatalysis: Ag-Doped TiO2 Catalyst Development and Reactor Design Testing

    Science.gov (United States)

    Coutts, Janelle L.; Hintze, Paul E.; Meier, Anne; Shah, Malay G.; Devor, Robert W.; Surma, Jan M.; Maloney, Phillip R.; Bauer, Brint M.; Mazyck, David W.

    2016-01-01

    In recent years, the alteration of titanium dioxide to become visible-light-responsive (VLR) has been a major focus in the field of photocatalysis. Currently, bare titanium dioxide requires ultraviolet light for activation due to its band gap energy of 3.2 eV. Hg-vapor fluorescent light sources are used in photocatalytic oxidation (PCO) reactors to provide adequate levels of ultraviolet light for catalyst activation; these mercury-containing lamps, however, hinder the use of this PCO technology in a spaceflight environment due to concerns over crew Hg exposure. VLR-TiO2 would allow for use of ambient visible solar radiation or highly efficient visible wavelength LEDs, both of which would make PCO approaches more efficient, flexible, economical, and safe. Over the past three years, Kennedy Space Center has developed a VLR Ag-doped TiO2 catalyst with a band gap of 2.72 eV and promising photocatalytic activity. Catalyst immobilization techniques, including incorporation of the catalyst into a sorbent material, were examined. Extensive modeling of a reactor test bed mimicking air duct work with throughput similar to that seen on the International Space Station was completed to determine optimal reactor design. A bench-scale reactor with the novel catalyst and high-efficiency blue LEDs was challenged with several common volatile organic compounds (VOCs) found in ISS cabin air to evaluate the system's ability to perform high-throughput trace contaminant removal. The ultimate goal for this testing was to determine if the unit would be useful in pre-heat exchanger operations to lessen condensed VOCs in recovered water thus lowering the burden of VOC removal for water purification systems.

  19. Development of Ternary and Quaternary Catalysts for the Electrooxidation of Glycerol

    Directory of Open Access Journals (Sweden)

    L. M. Artem

    2012-01-01

    Full Text Available This work consisted in the preparation of platinum-based catalysts supported on carbon (Vulcan XC-72 and investigation of their physicochemical and electrochemical properties. Catalysts of the C/Pt-Ni-Sn-Me (Me = Ru or Ir type were prepared by the Pechini method at temperature of 350∘C. Four different compositions were homemade: C/Pt60Sn10Ni30, C/Pt60Sn10Ni20Ru10, C/Pt60Sn10Ni10Ru20, and C/Pt60Sn10Ni10Ir20. These catalysts were electrochemically and physically characterized by cyclic voltammetry (CV, chronoamperometry (CA in the presence of glycerol 1.0 mol dm-3, X-ray diffraction (XRD, and high-resolution transmission electron microscopy (HRTEM. XRD results showed the main peaks of face-centered cubic Pt. The particle sizes obtained from XRD and HRTEM experiments were close to values ranging from 3 to 8.5 nm. The CV results indicate behavior typical of Pt-based catalysts in acid medium. The CV and CA data reveal that quaternary catalysts present the highest current density for the electrooxidation of glycerol.

  20. Development of Ternary and Quaternary Catalysts for the Electrooxidation of Glycerol

    Science.gov (United States)

    Artem, L. M.; Santos, D. M.; De Andrade, A. R.; Kokoh, K. B.; Ribeiro, J.

    2012-01-01

    This work consisted in the preparation of platinum-based catalysts supported on carbon (Vulcan XC-72) and investigation of their physicochemical and electrochemical properties. Catalysts of the C/Pt-Ni-Sn-Me (Me = Ru or Ir) type were prepared by the Pechini method at temperature of 350°C. Four different compositions were homemade: C/Pt60Sn10Ni30, C/Pt60Sn10Ni20Ru10, C/Pt60Sn10Ni10Ru20, and C/Pt60Sn10Ni10Ir20. These catalysts were electrochemically and physically characterized by cyclic voltammetry (CV), chronoamperometry (CA) in the presence of glycerol 1.0 mol dm−3, X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HRTEM). XRD results showed the main peaks of face-centered cubic Pt. The particle sizes obtained from XRD and HRTEM experiments were close to values ranging from 3 to 8.5 nm. The CV results indicate behavior typical of Pt-based catalysts in acid medium. The CV and CA data reveal that quaternary catalysts present the highest current density for the electrooxidation of glycerol. PMID:22623905

  1. Development and integration of a LabVIEW-based modular architecture for automated execution of electrochemical catalyst testing.

    Science.gov (United States)

    Topalov, Angel A; Katsounaros, Ioannis; Meier, Josef C; Klemm, Sebastian O; Mayrhofer, Karl J J

    2011-11-01

    This paper describes a system for performing electrochemical catalyst testing where all hardware components are controlled simultaneously using a single LabVIEW-based software application. The software that we developed can be operated in both manual mode for exploratory investigations and automatic mode for routine measurements, by using predefined execution procedures. The latter enables the execution of high-throughput or combinatorial investigations, which decrease substantially the time and cost for catalyst testing. The software was constructed using a modular architecture which simplifies the modification or extension of the system, depending on future needs. The system was tested by performing stability tests of commercial fuel cell electrocatalysts, and the advantages of the developed system are discussed.

  2. Development of heterogeneous olympic medal metal nanoparticle catalysts for environmentally benign molecular transformations based on the surface properties of hydrotalcite.

    Science.gov (United States)

    Kaneda, Kiyotomi; Mitsudome, Takato; Mizugaki, Tomoo; Jitsukawa, Koichiro

    2010-12-08

    In this review, we describe the development by our research group of highly functionalized heterogeneous Olympic medal metal (gold, silver, and copper) nanoparticle catalysts using hydrotalcite as a support, aimed towards Green and Sustainable Chemistry. Olympic medal metal nanoparticles can cooperate with the basic sites on the hydrotalcite surface, providing unique and high performance catalysis in environmentally-benign organic transformations such as aerobic oxidation of alcohols, lactonization of diols and selective deoxygenation of epoxides and nitro aromatic compounds.

  3. Development of Heterogeneous Olympic Medal Metal Nanoparticle Catalysts for Environmentally Benign Molecular Transformations Based on the Surface Properties of Hydrotalcite

    Directory of Open Access Journals (Sweden)

    Koichiro Jitsukawa

    2010-12-01

    Full Text Available In this review, we describe the development by our research group of highly functionalized heterogeneous Olympic medal metal (gold, silver, and copper nanoparticle catalysts using hydrotalcite as a support, aimed towards Green and Sustainable Chemistry. Olympic medal metal nanoparticles can cooperate with the basic sites on the hydrotalcite surface, providing unique and high performance catalysis in environmentally-benign organic transformations such as aerobic oxidation of alcohols, lactonization of diols and selective deoxygenation of epoxides and nitro aromatic compounds.

  4. Development of Heterogeneous Olympic Medal Metal Nanoparticle Catalysts for Environmentally Benign Molecular Transformations Based on the Surface Properties of Hydrotalcite

    OpenAIRE

    2010-01-01

    In this review, we describe the development by our research group of highly functionalized heterogeneous Olympic medal metal (gold, silver, and copper) nanoparticle catalysts using hydrotalcite as a support, aimed towards Green and Sustainable Chemistry. Olympic medal metal nanoparticles can cooperate with the basic sites on the hydrotalcite surface, providing unique and high performance catalysis in environmentally-benign organic transformations such as aerobic oxidation of alcohols, lactoni...

  5. Development of niobium-promoted cobalt catalysts on carbon nanotubes for Fischer-Tropsch synthesis

    Institute of Scientific and Technical Information of China (English)

    Sardar Ali; Noor Asmawati Mohd Zabidi; Duvvuri Subbarao

    2011-01-01

    Cobalt-based catalysts were prepared by a wet impregnation method on carbon nanotubes (CNTs) support and promoted with niobium.Samples were characterized by nitrogen adsorption,TEM,XRD,TPR,TPO and H2-TPD.Addition of niobium increased the dispersion of cobalt but decreased the catalysts reducibility.Fischer-Tropsch synthesis (FTS) was carried out in a fixed-bed microreactor at 543 K,1 atm and H2/CO =2 for 5 h.Addition of niobium enhanced the C5+ hydrocarbons selectivity by 39% and reduced methane selectivity by 59%.These effects were more pronounced for 0.04%Nb/Co/CNTs catalyst,compared with those observed for other niobium compositions.

  6. Catalyst Architecture

    DEFF Research Database (Denmark)

    Kiib, Hans; Marling, Gitte; Hansen, Peter Mandal

    2014-01-01

    of programs, have a role in mediating positive social and/or cultural development. In this sense, we talk about architecture as a catalyst for: sustainable adaptation of the city’s infrastructure appropriate renovation of dilapidated urban districts strengthening of social cohesiveness in the city development...... meaningful for everyone. The exhibited works are designed by SANAA, Diller Scofidio + Renfro, James Corner Field Operation, JBMC Arquitetura e Urbanismo, Atelier Bow-Wow, Ateliers Jean Nouvel, COBE, Transform, BIG, Topotek1, Superflex, and by visual artist Jane Maria Petersen....

  7. Development of advanced zeolite catalysts for the vapor phase Beckmann rearrangement of cyclohexanone oxime

    Science.gov (United States)

    Dai, Lian-Xin; Iwaki, Yoshihide; Koyama, Katsuyuki; Tatsumi, Takashi

    1997-11-01

    The vapor phase Beckmann rearrangement of cyclohexanone oxime to ɛ-caprolactam catalyzed by various zeolites was studied. The catalytic performance was greatly affected by both the zeolite structure and diluent solvent. When 1-hexanol was used in place of benzene, the catalytic performance of all catalysts except silicalite-1 was greatly improved. In particular, the selectivity and stability of H-LTL and H-OFF-ERI zeolites remarkably increased; both catalysts exhibited ca. 100% oxime conversion and ɛ-caprolactam selectivity of >95% for 6 h.

  8. Development of a New Combinatorial Approach to Multifunctional Catalysts: Metal Silsesquioxanes as Precursors to Microporous Metallosilicates

    Institute of Scientific and Technical Information of China (English)

    MAXIM, Nicolae

    2001-01-01

    Microporous, silica-supported netal oxides with a very narrow pore size distribution around 0.6 nm diameter, typicalsurface areas ranging from 350 to 700 m2/g, and loadings of well-dispersed metal oxide (up to w=10% of metal) result from thecontrolled calcination of silsesquioxane metal complexes. A versatile new methodology is envisioned that, in a combinatorial fashion, enables catalyst preparation with control over metal content and dispersity, together with adjustable Lewis and Bronsted acidity, In addition, the method is suitable for the preparation of bi-andmultifunctional catalysts containing different metals.

  9. Enhancement of Treatment Efficiency of Recalcitrant Wastewater Containing Textile Dyes Using a Newly Developed Iron Zeolite Socony Mobil-5 Heterogeneous Catalyst.

    Science.gov (United States)

    Ahmad, Mushtaq; Asghar, Anam; Abdul Raman, Abdul Aziz; Wan Daud, Wan Mohd Ashri

    2015-01-01

    Fenton oxidation, an advanced oxidation process, is an efficient method for the treatment of recalcitrant wastewaters. Unfortunately, it utilizes H2O2 and iron-based homogeneous catalysts, which lead to the formation of high volumes of sludge and secondary pollutants. To overcome these problems, an alternate option is the usage of heterogeneous catalyst. In this study, a heterogeneous catalyst was developed to provide an alternative solution for homogeneous Fenton oxidation. Iron Zeolite Socony Mobile-5 (Fe-ZSM-5) was synthesized using a new two-step process. Next, the catalyst was characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, fourier transform infrared spectroscopy, and Brunauer-Emmett-Teller analysis and tested against a model wastewater containing the azo dye Acid Blue 113. Results showed that the loading of iron particles reduced the surface area of the catalyst from 293.59 to 243.93 m2/g; meanwhile, the average particle size of the loaded material was 12.29 nm. Furthermore, efficiency of the developed catalyst was evaluated by performing heterogeneous Fenton oxidation. Taguchi method was coupled with principal component analysis in order to assess and optimize mineralization efficiency. Experimental results showed that under optimized conditions, over 99.7% degradation and 77% mineralization was obtained, with a 90% reduction in the consumption of the developed catalyst. Furthermore, the developed catalyst was stable and reusable, with less than 2% leaching observed under optimized conditions. Thus, the present study proved that newly developed catalyst has enhanced the oxidation process and reduced the chemicals consumption.

  10. Development of vanidum-phosphate catalysts for methanol production by selective oxidation of methane. Quarterly technical progress report, 1996

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, R.L.; Alptekin, G.O.

    1996-06-01

    Activities this past quarter, focused on acquisition of kinetic data for oxidation of formaldehyde and methanol on these catalysts. In the next quarter these results will be used to propose a simple reaction network and kinetic model. To date we have completed Task 1: Laboratory Setup and Task 2: Process Variable Study. Activities in the current quarter focused on finalizing these tasks and on Task 3: Promoters and Supports, this task is approximately 50% completed. Task 4: Advanced Catalysts is to be initiated in the next quarter. Specific accomplishments this quarter include: finalizing and calibrating a new reaction product analytical system with markedly improved precision and accuracy relative to older. approaches; development of procedures for accurately feeding formaldehyde to the reactor; examination of formaldehyde and methanol oxidation kinetics over vanadyl pyrophosphate at a range of temperatures; and preliminary studies of methane oxidation over a silica support.

  11. Theory-assisted development of a robust and Z-selective olefin metathesis catalyst.

    Science.gov (United States)

    Occhipinti, Giovanni; Koudriavtsev, Vitali; Törnroos, Karl W; Jensen, Vidar R

    2014-08-01

    DFT calculations have predicted a new, highly Z-selective ruthenium-based olefin metathesis catalyst that is considerably more robust than the recently reported (SIMes)(Cl)(RS)RuCH(o-OiPrC6H4) (3a, SIMes = 1,3-dimesityl-4,5-dihydroimidazol-2-ylidene, R = 2,4,6-triphenylbenzene) [J. Am. Chem. Soc., 2013, 135, 3331]. Replacing the chloride of 3a by an isocyanate ligand to give 5a was predicted to increase the stability of the complex considerably, at the same time moderately improving the Z-selectivity. Compound 5a is easily prepared in a two-step synthesis starting from the Hoveyda-Grubbs second-generation catalyst 3. In agreement with the calculations, the isocyanate-substituted 5a appears to be somewhat more Z-selective than the chloride analogue 3a. More importantly, 5a can be used in air, with unpurified and non-degassed substrates and solvents, and in the presence of acids. These are traits that are unprecedented among highly Z-selective olefin metathesis catalysts and also very promising with respect to applications of the new catalyst.

  12. Development of chiral metal amides as highly reactive catalysts for asymmetric [3 + 2] cycloadditions

    Science.gov (United States)

    Yamashita, Yasuhiro; Yoshimoto, Susumu; Dutton, Mark J

    2016-01-01

    Summary Highly efficient catalytic asymmetric [3 + 2] cycloadditions using a chiral copper amide are reported. Compared with the chiral CuOTf/Et3N system, the CuHMDS system showed higher reactivity, and the desired reactions proceeded in high yields and high selectivities with catalyst loadings as low as 0.01 mol %. PMID:27559396

  13. Kinetics and mechanism of 5-hydroxymethylfurfural oxidation and their implications for catalyst development

    NARCIS (Netherlands)

    Davis, S.E.; Benavidez, A.; Gosselink, R.W.; Bitter, J.H.; Jong, de K.P.; Datye, A.K.; Davis, R.J.

    2014-01-01

    The reaction mechanism of 5-hydroxymethylfurfural (HMF) oxidation in neutral aqueous solution with O2 to 5-hydroxymethyl-2-furancarboxylic acid (HFCA) and 2,5-furandicarboxylic acid (FDCA) was evaluated over a 3 wt% Pt/activated carbon catalyst in a semibatch reactor and confirmed that the mechanism

  14. Development of Nitric Oxide Oxidation Catalysts for the Fast SCR Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Mark Crocker

    2005-09-30

    This study was undertaken in order to assess the potential for oxidizing NO to NO{sub 2} in flue gas environments, with the aim of promoting the so-called fast SCR reaction. In principle this can result in improved SCR kinetics and reduced SCR catalyst volumes. Prior to commencing experimental work, a literature study was undertaken to identify candidate catalysts for screening. Selection criteria comprised (1) proven (or likely) activity for NO oxidation, (2) low activity for SO2 oxidation (where data were available), and (3) inexpensive component materials. Catalysts identified included supported base metal oxides, supported and unsupported mixed metal oxides, and metal ion exchanged ZSM-5 (Fe, Co, Cu). For comparison purposes, several low loaded Pt catalysts (0.5 wt% Pt) were also included in the study. Screening experiments were conducted using a synthetic feed gas representative of flue gas from coal-fired utility boilers: [NO] = 250 ppm, [SO{sub 2}] = 0 or 2800 ppm, [H{sub 2}O] = 7%, [CO{sub 2}] = 12%, [O{sub 2}] = 3.5%, balance = N{sub 2}; T = 275-375 C. Studies conducted in the absence of SO{sub 2} revealed a number of supported and unsupported metal oxides to be extremely active for NO oxidation to NO{sub 2}. These included known catalysts (Co{sub 3}O{sub 4}/SiO{sub 2}, FeMnO{sub 3}, Cr{sub 2}O{sub 3}/TiO{sub 2}), as well as a new one identified in this work, CrFeO{sub x}/SiO{sub 2}. However, in the presence of SO{sub 2}, all the catalysts tested were found to be severely deactivated with respect to NO oxidation. Of these, Co{sub 3}O{sub 4}/SiO{sub 2}, Pt/ZSM-5 and Pt/CeO{sub 2} showed the highest activity for NO oxidation in the presence of SO{sub 2} (based on peak NO conversions to NO{sub 2}), although in no cases did the NO conversion exceed 7%. Reactor studies indicate there are two components to SO{sub 2}-induced deactivation of Co{sub 3}O{sub 4}/SiO{sub 2}, corresponding to an irreversible deactivation due to sulfation of the surface of the Co{sub 3

  15. Recent progress in the development of solid catalysts for biomass conversion into high value-added chemicals

    Science.gov (United States)

    Hara, Michikazu; Nakajima, Kiyotaka; Kamata, Keigo

    2015-01-01

    In recent decades, the substitution of non-renewable fossil resources by renewable biomass as a sustainable feedstock has been extensively investigated for the manufacture of high value-added products such as biofuels, commodity chemicals, and new bio-based materials such as bioplastics. Numerous solid catalyst systems for the effective conversion of biomass feedstocks into value-added chemicals and fuels have been developed. Solid catalysts are classified into four main groups with respect to their structures and substrate activation properties: (a) micro- and mesoporous materials, (b) metal oxides, (c) supported metal catalysts, and (d) sulfonated polymers. This review article focuses on the activation of substrates and/or reagents on the basis of groups (a)–(d), and the corresponding reaction mechanisms. In addition, recent progress in chemocatalytic processes for the production of five industrially important products (5-hydroxymethylfurfural, lactic acid, glyceraldehyde, 1,3-dihydroxyacetone, and furan-2,5-dicarboxylic acid) as bio-based plastic monomers and their intermediates is comprehensively summarized. PMID:27877800

  16. Design and Stereoselective Preparation of a New Class of Chiral Olefin Metathesis Catalysts and Application to Enantioselective Synthesis of Quebrachamine: Catalyst Development Inspired by Natural Product Synthesis

    Science.gov (United States)

    Sattely, Elizabeth S.; Meek, Simon J.; Malcolmson, Steven J.; Schrock, Richard R.; Hoveyda, Amir H.

    2010-01-01

    A total synthesis of the Aspidosperma alkaloid quebrachamine in racemic form is first described. A key catalytic ring-closing metathesis of an achiral triene is used to establish the all-carbon quaternary stereogenic center and the tetracyclic structure of the natural product; the catalytic transformation proceeds with reasonable efficiency through the use of existing achiral Ru or Mo catalysts. Ru- or Mo-based chiral olefin metathesis catalysts have proven to be inefficient and entirely nonselective in cases where the desired product is observed. In the present study, the synthesis route thus serves as a platform for the discovery of new olefin metathesis catalysts that allow for efficient completion of an enantioselective synthesis of quebrachamine. Accordingly, on the basis of mechanistic principles, stereogenic-at-Mo complexes bearing only monodentate ligands have been designed. The new catalysts provide significantly higher levels of activity than observed with the previously reported Ru- or Mo-based complexes. Enantiomerically enriched chiral alkylidenes are generated through diastereoselective reactions involving achiral Mo-based bispyrrolides and enantiomerically pure silyl-protected binaphthols. Such chiral catalysts initiate the key enantioselective ring-closing metathesis step in the total synthesis of quebrachamine efficiently (1 mol % loading, 22 °C, 1 h, >98% conversion, 84% yield) and with high selectivity (98:2 er, 96% ee). PMID:19113867

  17. Development of the advanced nuclear materials -A study on the polymer catalyst process technology-

    Energy Technology Data Exchange (ETDEWEB)

    Kook, Il Hyun; Jung, Heung Suk; Lee, Han Soo; An, Doh Heui; Kang, Heui Suk; Baek, Seung Woo; Lee, Sung Hoh; Sung, Kee Woong; Kim, Kwang Lak; Kim, Jong Hoh; Koo, Je Hyoo; Park, Tae Keun; Kim, Sang Hwan; Yoo, Ryong; Song, Myung Jae; Son, Soon Hwan; Choi, Jung Kil; Lee, Jae Choon; Jung, Moon Kyoo [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-07-01

    Heavy water is used as moderator and coolant in pressurized heavy water power plants. According to the governmental long-term plan for power supply, Korea is scheduled to construct new four pressurized heavy water power plants till the year 2006. Total heavy water make-up for these plants would be 22 Mg/a from the year 2006. Reformed hydrogen processes is considered best suited to Korea. Hydrophobic catalysts for this process were manufactured and the performance of hydrogen isotope exchange was investigated. The overall mass transfer coefficients varied between 0.004 and 2.295 m3 HD/m3 Bed.sec. and heavy water separation processes using the catalysts were optimized. 66 figs, 62 tabs, 19 refs. (Author).

  18. Development of a tailor-made bis(oxazolidine)pyridine-metal catalyst for the [3+2] cycloaddition of azomethine imines with propiolates.

    Science.gov (United States)

    Arai, Takayoshi; Ogino, Yuta; Sato, Toru

    2013-09-14

    A series of bis(oxazolidine)pyridine ligands (the PyBodines) were newly designed and synthesized for the development of a highly efficient, tailor-made catalyst for the [3+2] cycloaddition of azomethine imines with propiolates. The PyBodine(l-Ala)-Cu(OAc)2 catalyst was selected on the basis of solid-phase catalysis/CD-HTS and exhibited high efficiency, producing the (R)-adducts with excellent enantioselectivity.

  19. College Students' Possible L2 Self Development in an EFL Context during the Transition Year

    Science.gov (United States)

    Zhan, Ying; Wan, Zhi Hong

    2016-01-01

    In the field of second language learning motivation, the studies on process-oriented nature of possible L2 selves are scarce. In order to address this research gap, this study explored how a group of five Chinese non-English-major undergraduates developed their possible L2 selves during the transition year from high school to university. The…

  20. Sustainable Utility of Magnetically Recyclable Nano-Catalysts in Water: Applications in Organic Synthesis

    Directory of Open Access Journals (Sweden)

    Manoj B. Gawande

    2013-10-01

    Full Text Available Magnetically recyclable nano-catalysts and their use in aqueous media is a perfect combination for the development of greener sustainable methodologies in organic synthesis. It is well established that magnetically separable nano-catalysts avoid waste of catalysts or reagents and it is possible to recover >95% of catalysts, which is again recyclable for subsequent use. Water is the ideal medium to perform the chemical reactions with magnetically recyclable nano-catalysts, as this combination adds tremendous value to the overall benign reaction process development. In this review, we highlight recent developments inthe use of water and magnetically recyclable nano-catalysts (W-MRNs for a variety of organic reactions namely hydrogenation, condensation, oxidation, and Suzuki–Miyaura cross-coupling reactions, among others.

  1. Development of an Innovative XRD-DRIFTS Prototype Allowing Operando Characterizations during Fischer-Tropsch Synthesis over Cobalt-Based Catalysts under Representative Conditions

    Directory of Open Access Journals (Sweden)

    Scalbert Julien

    2015-03-01

    Full Text Available An original system combining both X-Ray Diffraction and diffuse reflectance infrared Fourier transform spectroscopy was developed with the aim to characterize Fischer-Tropsch catalysts in relevant reaction conditions. The catalytic properties of a model PtCo/silica catalyst tested with this prototype have shown to be in the same range of those obtained in similar conditions with classical fixed-bed reactors. No bulk cobalt oxidation nor sintering were observed on operando XRD patterns. The formation of linear carbonyls and adsorbed hydrocarbons species at the surface of the catalyst was observed on operando DRIFT spectra. The surface of the catalyst was also suspected to be covered with carbon species inducing unfavorable changes in selectivity.

  2. Catalyst and process development for synthesis gas conversion to isobutylene. Final report, September 1, 1990--January 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Anthony, R.G.; Akgerman, A.; Philip, C.V.; Erkey, C.; Feng, Z.; Postula, W.S.; Wang, J.

    1995-03-01

    This project was initiated because the supply of isobutylene had been identified as a limitation on the production of methyl-t-butyl ether, a gasoline additive. Prior research on isobutylene synthesis had been at low conversion (less than 5%) or extremely high pressures (greater than 300 bars). The purpose of this research was to optimize the synthesis of a zirconia based catalyst, determine process conditions for producing isobutylene at pressures less than 100 bars, develop kinetic and reactor models, and simulate the performance of fixed bed, trickle bed and slurry flow reactors. A catalyst, reactor models and optimum operating conditions have been developed for producing isobutylene from coal derived synthesis gas. The operating conditions are much less severe than the reaction conditions developed by the Germans during and prior to WWII. The low conversion, i.e. CO conversion less than 15%, have been perceived to be undesirable for a commercial process. However, the exothermic nature of the reaction and the ability to remove heat from the reactor could limit the extent of conversion for a fixed bed reactor. Long residence times for trickle or slurry (bubble column) reactors could result in high CO conversion at the expense of reduced selectivities to iso C{sub 4} compounds. Economic studies based on a preliminary design, and a specific location will be required to determine the commercial feasibility of the process.

  3. Catalyst development and systems analysis of methanol partial oxidation for the fuel processor - fuel cell integration

    Energy Technology Data Exchange (ETDEWEB)

    Newson, E.; Mizsey, P.; Hottinger, P.; Truong, T.B.; Roth, F. von; Schucan, Th.H. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    Methanol partial oxidation (pox) to produce hydrogen for mobile fuel cell applications has proved initially more successful than hydrocarbon pox. Recent results of catalyst screening and kinetic studies with methanol show that hydrogen production rates have reached 7000 litres/hour/(litre reactor volume) for the dry pox route and 12,000 litres/hour/(litre reactor volume) for wet pox. These rates are equivalent to 21 and 35 kW{sub th}/(litre reactor volume) respectively. The reaction engineering problems remain to be solved for dry pox due to the significant exotherm of the reaction (hot spots of 100-200{sup o}C), but wet pox is essentially isothermal in operation. Analyses of the integrated fuel processor - fuel cell systems show that two routes are available to satisfy the sensitivity of the fuel cell catalysts to carbon monoxide, i.e. a preferential oxidation reactor or a membrane separator. Targets for individual system components are evaluated for the base and best case systems for both routes to reach the combined 40% efficiency required for the integrated fuel processor - fuel cell system. (author) 2 figs., 1 tab., 3 refs.

  4. Developing an approach for first-principles catalyst design: application to carbon-capture catalysis.

    Science.gov (United States)

    Kulik, Heather J; Wong, Sergio E; Baker, Sarah E; Valdez, Carlos A; Satcher, Joe H; Aines, Roger D; Lightstone, Felice C

    2014-02-01

    An approach to catalyst design is presented in which local potential energy surface models are first built to elucidate design principles and then used to identify larger scaffold motifs that match the target geometries. Carbon sequestration via hydration is used as the model reaction, and three- and four-coordinate sp(2) or sp(3) nitrogen-ligand motifs are considered for Zn(II) metals. The comparison of binding, activation and product release energies over a large range of interaction distances and angles suggests that four-coordinate short Zn(II)-Nsp(3) bond distances favor a rapid turnover for CO2 hydration. This design strategy is then confirmed by computationally characterizing the reactivity of a known mimic over a range of metal-nitrogen bond lengths. A search of existing catalysts in a chemical database reveals structures that match the target geometry from model calculations, and subsequent calculations have identified these structures as potentially effective for CO2 hydration and sequestration.

  5. Development of Light Cycle Oil (LCO) Hydrocracking Technology over a Commercial W-Ni Based Catalyst

    Institute of Scientific and Technical Information of China (English)

    Peng Chong; Yang Xuejing; Fang Xiangchen; Huang Xinlu; Cheng Zhenmin; Zeng Ronghui; Guo Rong

    2015-01-01

    Because of its high density and low cetane number, the light cycle oil (LCO) containing heavy aromatics (60%—80%) can hardly be transformed through the conventional hydro-upgrading technology. In this report, a novel LCO hydrocracking technology (FD2G) was proposed for the utilization of LCO to manufacture high value-added products. Through the ingenious combination of hydroprocessing catalyst and the hydrocracking process, the high octane gasoline and the ultra-low sulfur diesel (ULSD) blendstocks were produced simultaneously. The inlfuence of catalyst type, reaction temperature, pressure, respectively, on the research octane number (RON) of produced gasoline was studied in a ifxed bed hydrogenation reactor. It indicated that high reaction temperature and medium pressurewould favor the production of high-octane gasoline through the conversion of bi-aromatic and tri-aromatic hydrocarbons. The typical results of FD2G tech-nology on commercial units showed that it could produce clean diesel with a sulfur content of less than 10 μg/g and clean gasoline with a research octane number (RON) of up to 92. It would be contributed to the achievement of the maximum proift of a reifnery, the FD2G technology could provide a higher economic efifciency than the other diesel quality upgrading technology under the current gasoline and diesel price system.

  6. Homogeneous catalysts

    CERN Document Server

    Chadwick, John C; Freixa, Zoraida; van Leeuwen, Piet W N M

    2011-01-01

    This first book to illuminate this important aspect of chemical synthesis improves the lifetime of catalysts, thus reducing material and saving energy, costs and waste.The international panel of expert authors describes the studies that have been conducted concerning the way homogeneous catalysts decompose, and the differences between homogeneous and heterogeneous catalysts. The result is a ready reference for organic, catalytic, polymer and complex chemists, as well as those working in industry and with/on organometallics.

  7. Using ICTs (Educationally) for Development in an African Context: Possibilities and Limitations

    Science.gov (United States)

    Carrim, Nazir; Taruvinga, Mandi

    2015-01-01

    This article examines the possibilities and limitations of using ICTs for development in an African context from an education perspective. Although we provide an account of the Pan-African Agenda on integrating ICTs, which covers many countries on the African continent, our focus is specifically on using ICTs for development in a South African…

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

    Science.gov (United States)

    Nguyen, Luan; Tao, Franklin Feng

    2016-06-01

    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.

  9. Development of Ni-Based Catalysts Derived from Hydrotalcite-Like Compounds Precursors for Synthesis Gas Production via Methane or Ethanol Reforming

    Directory of Open Access Journals (Sweden)

    Ya-Li Du

    2017-02-01

    Full Text Available As a favorably clean fuel, syngas (synthesis gas production has been the focus of concern in past decades. Substantial literatures reported the syngas production by various catalytic reforming reactions particularly in methane or ethanol reforming. Among the developed catalysts in these reforming processes, Ni-based catalysts from hydrotalcite-like compounds (HTLcs precursors have drawn considerable attention for their preferable structural traits. This review covers the recent literature reporting syngas production with Ni-based catalysts from HTLc precursors via methane or ethanol reforming. The discussion was initiated with catalyst preparation (including conventional and novel means, followed by subsequent thermal treatment processes, then composition design and the addition of promoters in these catalysts. As Ni-based catalysts have thermodynamic potential to deactivate because of carbon deposition or metal sintering, measures for dealing with these problems were finally summarized. To obtain optimal catalytic performances and resultantly better syngas production, based on analyzing the achievements of the references, some perspectives were finally proposed.

  10. DEVELOPMENT OF NEW TYPE ALUMINIUM OXIDE MATRIX CATALYST FOR PREPARATION OF SULFUR%新型氧化铝基制硫催化剂的研制

    Institute of Scientific and Technical Information of China (English)

    商剑峰; 刘爱华; 罗保军; 刘剑利

    2012-01-01

    The paper described the development, characterization and activity valuation of LS -02 new type aluminium oxide matrix catalyst for preparation of sulfur. The LS -02 catalyst was prepared by rotation shaping process and aluminium oxide as main raw material. Compared with LS -300 catalyst, the LS -02 catalyst possessed higher specific surface area, larger pore volume, more reasonable distribution of pore size and higher Claus and hydrolyzation reactivity. Comprehensive properties of the LS -02 catalyst reached foreign similar catalyst.%介绍了LS-02新型氧化铝制硫催化剂的研制、表征及活性评价。该催化剂以氧化铝为主要原料,采用转动成型工艺制备。该催化剂较LS-300催化剂具有更高的比表面积、更大的孔体积、更合理的孔分布及更高的克劳斯活性和水解活性,综合性能达到国外同类催化剂水平。

  11. Development of Optimal Catalyst Designs and Operating Strategies for Lean NOx Reduction in Coupled LNT-SCR Systems

    Energy Technology Data Exchange (ETDEWEB)

    Harold, Michael; Crocker, Mark; Balakotaiah, Vemuri; Luss, Dan; Choi, Jae-Soon; Dearth, Mark; McCabe, Bob; Theis, Joe

    2013-09-30

    hydrocarbon component of diesel exhaust. First-principle models of the LNT and SCR converters, which utilized the mechanistic-based kinetics and realistic treatments of the flow and transport processes, in combination with bench-scale reactor experiments helped to identify the best designs for combining the NSR and SCR catalysts over a range of operating conditions encountered in practice. This included catalysts having multiple zones and layers and additives with the focus on determining the minimal precious metal component needed to meet emission abatement targets over a wide range of operating conditions. The findings from this study provide diesel vehicle and catalyst companies valuable information to develop more cost effective diesel emissions catalysts which helps to expand the use of more fuel efficient diesel power. The fundamental modeling and experimental tools and findings from this project can be applied to catalyst technologies used in the energy and chemical industries. Finally, the project also led to training of several doctoral students who were placed in research jobs in industry and academia.

  12. Monocausalism Versus Systems Approach To Development? The Possibility Of Natural Resource-Based Development

    DEFF Research Database (Denmark)

    Andersen, Allan Dahl; Johnson, Björn

    2011-01-01

    natural resources can be a curse as well as a blessing. But if you can build an institutional framework for the utilization of specific natural resources, which supports development of new knowledge and competences that can be applied in a range of different activities, resource based development...... as systemic. Throughout the paper there is a focus on natural resource-based development. It has been argued that abundant natural resources are detrimental to economic development – an argument known as the resource curse, which is one type of ‘production structure fundamentalism’. We argue that abundant...

  13. Monocausalism versus systems approach to development - The possibility of natural resource-based development

    DEFF Research Database (Denmark)

    Andersen, Allan; Johnson, Bjørn

    2011-01-01

    natural resources can be a curse as well as a blessing. But if you can build an institutional framework for the utilization of specific natural resources, which supports development of new knowledge and competences that can be applied in a range of different activities, resource based development...... as systemic. Throughout the paper there is a focus on natural resource-based development. It has been argued that abundant natural resources are detrimental to economic development – an argument known as the resource curse, which is one type of ‘production structure fundamentalism’. We argue that abundant...

  14. The generation of efficient supported (Heterogeneous) olefin metathesis catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Grubbs, Robert H

    2013-04-05

    Over the past decade, a new family of homogeneous metathesis catalysts has been developed that will tolerate most organic functionalities as well as water and air. These homogeneous catalysts are finding numerous applications in the pharmaceutical industry as well as in the production of functional polymers. In addition the catalysts are being used to convert seed oils into products that can substitute for those that are now made from petroleum products. Seed oils are unsaturated, contain double bonds, and are a ready source of linear hydrocarbon fragments that are specifically functionalized. To increase the number of applications in the area of biomaterial conversion to petrol chemicals, the activity and efficiency of the catalysts need to be as high as possible. The higher the efficiency of the catalysts, the lower the cost of the conversion and a larger number of practical applications become available. Active supported catalysts were prepared and tested in the conversion of seed oils and other important starting materials. The outcome of the work was successful and the technology has been transferred to a commercial operation to develop viable applications of the discovered systems. A biorefinery that converts seed oils is under construction in Indonesia. The catalysts developed in this study will be considered for the next generation of operations.

  15. Brief Communication: CATALYST - a multi-regional stakeholder think tank for fostering capacity development in disaster risk reduction and climate change adaptation

    Science.gov (United States)

    Hare, M. P.; van Bers, C.; van der Keur, P.; Henriksen, H. J.; Luther, J.; Kuhlicke, C.; Jaspers, F.; Terwisscha van Scheltinga, C.; Mysiak, J.; Calliari, E.; Warner, K.; Daniel, H.; Coppola, J.; McGrath, P. F.

    2014-08-01

    This brief communication presents the work and objectives of the CATALYST project on "Capacity Development for Hazard Risk Reduction and Adaptation" funded by the European Commission (October 2011-September 2013). CATALYST set up a multi-regional think tank covering four regions (Central America and the Caribbean, East and West Africa, the European Mediterranean, and South and Southeast Asia), intending to strengthen capacity development for stakeholders involved in disaster risk reduction (DRR) and climate change adaptation, in the context of natural hazards. This communication concludes with a selection of recommendations for capacity development in DRR and climate change adaptation from the perspective of governance issues.

  16. Development of a Method for the Preparation of Ruthenium Indenylidene-Ether Olefin Metathesis Catalysts

    Science.gov (United States)

    Jimenez, Leonel R.; Tolentino, Daniel R.; Gallon, Benjamin J.; Schrodi, Yann

    2012-01-01

    The reactions between several derivatives of 1-(3,5-dimethoxyphenyl)-prop-2-yn-1-ol and different ruthenium starting materials [i.e., RuCl2(PPh3)3 and RuCl2(pcymene)(L), where L is tricyclohexylphosphine di-t-butylmethylphosphine, dicyclohexylphenylphosphine, triisobutylphosphine, triisopropylphosphine, or tri-npropylphosphine] are described. Several of these reactions allow for the easy, in-situ and atom-economic preparation of olefin metathesis catalysts. Organic precursor 1-(3,5-dimethoxyphenyl)-1-phenyl-prop-2-yn-1-ol led to the formation of active ruthenium indenylidene-ether complexes, while 1-(3,5-dimethoxyphenyl)-prop-2-yn-1-ol and 1-(3,5-dimethoxyphenyl)-1-methyl-prop-2-yn-1-ol did not. It was also found that a bulky and strong σ-donor phosphine ligand was required to impart good catalytic activity to the new ruthenium complexes. PMID:22580400

  17. High-Activity Dealloyed Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Kongkanand, Anusorn [General Motors LLC, Pontiac, MI (United States)

    2014-09-30

    Reduction of costly Pt usage in proton exchange membrane fuel cell electrodes is one of the major challenges towards development and commercialization of fuel cell vehicles. Although few have met the initial-kinetic activity requirements in a realistic fuel cell device, no catalyst material has ever met the demanding fuel cell durability targets set by DOE. In this project, a team of 4 universities and 2 companies came together to investigate a concept that appeared promising in preliminary non-fuel cell tests then to further develop the catalyst to a mature level ready for vehicle implementation. The team consists of academia with technical leadership in their respective areas, a catalyst supplier, and a fuel cell system integrator.The tightly collaborative project enabled development of a highly active and durable catalyst with performance that significantly exceeds that of previous catalysts and meets the DOE targets for the first time (Figure 1A). The catalyst was then further evaluated in full-active-area stack in a realistic vehicle operating condition (Figure 1B). This is the first public demonstration that one can realize the performance benefit and Pt cost reduction over a conventional pure Pt catalyst in a long-term realistic PEMFC system. Furthermore, systematic analyses of a range of catalysts with different performance after fuel cell testing allowed for correlation between catalyst microstructure and its electrocatalytic activity and durability. This will in turn aid future catalyst development.

  18. Generating PDS Possibility and Practicality Thinking Using a Case and Protocol Tool to Enhance PDS Development

    Science.gov (United States)

    Yendol-Hoppey, Diane; Hoppey, David

    2013-01-01

    An important feature of professional development school (PDS) work is encouraging collaborative reflective dialogue that guides a partnership toward actualizing the possibilities for and mission of a PDS. This article provides a case "illustration" of a fictitious, exemplary PDS and a "protocol" that in combination can be used…

  19. Possible Science Selves: Informal Learning and the Career Interest Development Process

    Science.gov (United States)

    Mills, Leila A.

    2014-01-01

    This research examines the relationship between career related self-concept and dimensions of informal learning of science. The overlapping dimensions of career interest development and informal learning suggest that self-directed informal learning of science can advance individual self-concept for "possible scientific self." Possible…

  20. Supported Molten Metal Catalysis. A New Class of Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Ravindra Datta; Ajeet Singh; Manuela Serban; Istvan Halasz

    2006-06-02

    We describe a new class of heterogeneous catalysts called supported molten metal catalysis (SMMC), in which molten metal catalysts are dispersed as nanodroplets on the surface of porous supports, allowing much larger active surface area than is possible in conventional contacting techniques for catalytic metals that are molten under reaction conditions, thus greatly enhancing their activity and potential utility. Specific examples of different types of reactions are provided to demonstrate the broad applicability of the technique in designing active, selective, and stable new catalysts. It is shown that dispersing the molten metal on a support in the suggested manner can enhance the rate of a reaction by three to four orders of magnitude as a result of the concomitant increase in the active surface area. New reaction examples include {gamma}-Al{sub 2}O{sub 3} supported molten Te (melting point 450 C) and Ga (MP 30 C) catalysts for bifunctional methylcyclohexane dehydrogenation. These catalysts provide activity similar to conventional Pt-based catalysts for this with better resistance to coking. In addition, results are described for a controlled pore glass supported molten In (MP 157 C) catalyst for the selective catalytic reduction of NO with ethanol in the presence of water, demonstrating activities superior to conventional catalysts for this reaction. A discussion is also provided on the characterization of the active surface area and dispersion of these novel supported catalysts. It is clear based on the results described that the development of new active and selective supported molten metal catalysts for practical applications is entirely plausible.

  1. Development of a Method for the Preparation of Ruthenium Indenylidene-Ether Olefin Metathesis Catalysts

    Directory of Open Access Journals (Sweden)

    Yann Schrodi

    2012-05-01

    Full Text Available The reactions between several derivatives of 1-(3,5-dimethoxyphenyl-prop-2-yn-1-ol and different ruthenium starting materials [i.e., RuCl2(PPh33 and RuCl2(p-cymene(L, where L is tricyclohexylphosphine di-t-butylmethylphosphine, dicyclohexylphenylphosphine, triisobutylphosphine, triisopropylphosphine, or tri-n-propylphosphine] are described. Several of these reactions allow for the easy, in-situ and atom-economic preparation of olefin metathesis catalysts. Organic precursor 1-(3,5-dimethoxyphenyl-1-phenyl-prop-2-yn-1-ol led to the formation of active ruthenium indenylidene-ether complexes, while 1-(3,5-dimethoxyphenyl-prop-2-yn-1-ol and 1-(3,5-dimethoxyphenyl-1-methyl-prop-2-yn-1-ol did not. It was also found that a bulky and strong σ-donor phosphine ligand was required to impart good catalytic activity to the new ruthenium complexes.

  2. Development of new heterogeneous catalysts for the decomposition of methanol into hydrogen and carbon monoxide applying high throughput methods; Entwicklung neuer heterogener Katalysatoren zur Spaltung von Methanol in Wasserstoff und Kohlenmonoxid mittels Hochdurchsatz-Methoden

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, Torsten

    2008-07-11

    The topic of this thesis has been the development of new heterogeneous catalysts for the decomposition of methanol into hydrogen and carbon monoxide. As an important constraint here, the content of noble metals of the catalysts should be as low as possible. High-throughput-methods were applied in some of the syntheses and experiments to accelerate the development, as, for example, the use of liquid based sol-gel syntheses and the examination of catalyst libraries by spatial resolution gas chromatography. This screening technique allowed to test up to 207 different substances during one single experiment. Then, different combinatorial strategies were applied. First, these methods led to a highly active and stable catalyst in the ternary system of Cu-Ni-Zn, which showed high conversion and selectivity comparable to an industrial reference catalyst. Its activity during an 18 hour long term run was constant in contrast to the reference. Second, an additional approach starting from a broader variety of elements led to a Ce- Ru- and to a Cr-Ru-catalyst. Both of them were highly active in short term experiments, but lost their outstanding performances during long term runs. (orig.) [German] Die vorliegende Arbeit befasste sich mit der Entwicklung neuer heterogener Katalysatoren fuer die Spaltung von Methanol zu Wasserstoff und Kohlenmonoxid, die einen moeglichst geringen Gehalt an Edelmetallen aufweisen sollten. Um diesen Prozess zu beschleunigen, wurden in einem Teil der Synthesen und Experimente Hochdurchsatzmethoden verwendet. Neben der Roboter gestuetzten Sol-Gel-Synthese umfasste dies die Untersuchung von Katalysatorbibliotheken mittels ortsaufgeloester Gaschromatographie, die es ermoeglichte, in einem Experiment bis zu 207 verschiedene Substanzen auf ihre katalytische Aktivitaet zu testen. Unter Anwendung verschiedener kombinatorischer Strategien wurde zunaechst ein sehr aktiver und stabiler Katalysator im ternaeren Cu-Ni-Zn-System entdeckt. Neben Umsaetzen und

  3. Long-term predictions of the energy development - possibilities and challenges

    Directory of Open Access Journals (Sweden)

    Kanevce Gligor

    2016-01-01

    Full Text Available In this paper the possibilities, disadvantages and benefits of long-term planning of energy development, are analysed. The factors influencing the development of energy and the factors influencing the accuracy of forecasting of the future development of energy are presented. The uncertainties that make the differences in modelling on a global scale, as well as the uncertainties that make the differences in modelling of the energy development of the Republic of Macedonia are also presented. Sensitivity analysis of the influence of different factors on the development of energy in the Republic of Macedonia was carried out. For those purposes the energy development of the Republic of Macedonia for the period up to 2035 year is calculated by using MARKAL model. The main features of the MARKAL model are also presented.

  4. Investigation of titanium nitride as catalyst support material and development of durable electrocatalysts for proton exchange membrane fuel cells

    Science.gov (United States)

    Avasarala, Bharat K.

    The impending energy and climatic crisis makes it imperative for human society to seek non-fossil based alternative sources for our energy needs. Although many alternative energy technologies are currently being developed, fuel cell technology provides energy solutions, which satisfy a wide range of applications. But the current fuel cell technology is far from its target of large scale commercialization mainly because of its high cost and poor durability. Considerable work has been done in reducing the cost but its durability still needs significant improvement. Of the various materials in a PEM fuel cell, the degradation of electrocatalyst affects its durability the most, leading to performance loss. Carbon black (C) support corrosion plays a significant role in the electrocatalyst degradation and its severe affects due to potential cycling has been identified through my research. Through my resaerch, I introduce titanium nitride nanoparticles (TiN NP) as alternative catalyst supports replacing carbon black. TiN NP has higher electrical conductivity and corrosion resistance compared to that of C. The physical and electrochemical properties of TiN NP were studied and the Pt/TiN electrocatalyst was synthesized using polyol process. Upon optimizing using DOE, for desired catalyst particle size and activity, Pt/TiN is shown to have higher catalytic performance than conventional Pt/C. TiN NP are significantly influenced by the electrochemical conditions and show 'active' or 'passive' nature depending on the temperature and acidic concentration; and a temperature dependence model is proposed to understand the active/passive nature of TiN NP. A one-to-one comparison between TiN NP and C electrodes under similar electrochemical conditions show a superior performance of TiN NP as a catalyst support. The durability of the Pt/TiN electrocatalyst is also tested and it agrees well with the proposed model of active/passive nature of the TiN NP. Through theoretical calculation

  5. Base-Catalyzed Depolymerization of Lignin with Heterogeneous Catalysts: Cooperative Research and Development Final Report, CRADA Number CRD-13-513

    Energy Technology Data Exchange (ETDEWEB)

    Beckham, Gregg T. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-08-04

    We will synthesize and screen solid catalysts for the depolymerization of lignin to monomeric and oligomeric oxygenated species, which could be fractionated and integrated into refinery intermediate streams for selective upgrading, or catalytically upgraded to fuels and chemicals. This work will primarily focus on the synthesis and application of layered double hydroxides (LDHs) as recyclable, heterogeneous catalysts for depolymerization of lignin model compounds and softwood lignin. LDHs have been shown in our group to offer good supports and catalysts to promote base-catalyzed depolymerization of lignin model compounds and in preliminary experiments for the depolymerization of lignin from an Organosolv process. We will also include additional catalyst supports such as silica, alumina, and carbon as identified in ongoing and past efforts at NREL. This work will consist of two tasks. Overall, this work will be synergistic with ongoing efforts at NREL, funded by the DOE Biomass Program, on the development of catalysts for lignin depolymerization in the context of biochemical and thermochemical conversion of corn stover and other biomass feedstocks to advanced fuels and chemicals.

  6. Mesoporous molecular sieve catalysts

    DEFF Research Database (Denmark)

    Højholt, Karen Thrane

    be used as solid acid catalysts but can also be used as a size-selective matrix. It was shown that it is possible to encapsulate 1-2 nm sized gold nanoparticles by silicalite-1 or ZSM-5 zeolite crystals thereby forming a sintering-stable and substrate size-selective oxidation catalyst. After carrying out...... calcination experiments, both in situ and ex situ indicated that the gold nanoparticles embedded in the crystals were highly stable towards sintering. The catalytic tests proved that the embedded gold nanoparticles were active in selective aldehyde oxidation and were only accessible through the micropores...

  7. Development of a catalyst for conversion of syngas-derived materials to isobutylene. Quarterly report, 1 January 1995--31 March 1995

    Energy Technology Data Exchange (ETDEWEB)

    Barger, P.T.; Kurek, P.R.

    1995-12-31

    The goals of this project are to develop a catalyst and process for the conversion of syngas to isobutanol. The research will identify and optimize key catalyst characteristics. In addition, the commercial potential of the new process will be evaluated by an economic analysis. Previous work identified Pt or Pd on Zn/Mn/Zr co-precipitated metal oxides as promising catalysts for the conversion of a 10/1 methanol/ethanol blend to higher oxygenates. Supports with high Zn (>45%) and low Zr (< 33%) have afforded the best selectivities for the desired branched C{sub 4} products in the standard pilot plant test after impregnation with 2% Pt. In this report the analytical characterization of this series of materials is summarized. A large scale preparation of Zn/Mn/Zr oxide support has been completed for use in future process variable studies.

  8. Cathodic catalysts in bioelectrochemical systems for energy recovery from wastewater.

    Science.gov (United States)

    Liu, Xian-Wei; Li, Wen-Wei; Yu, Han-Qing

    2014-11-21

    Bioelectrochemical systems (BESs), in which microorganisms are utilized as a self-regenerable catalyst at the anode of an electrochemical cell to directly extract electrical energy from organic matter, have been widely recognized as a promising technology for energy-efficient wastewater treatment or even for net energy generation. However, currently BES performance is constrained by poor cathode reaction kinetics. Thus, there is a strong impetus to improve the cathodic catalysis performance through proper selection and design of catalysts. This review introduces the fundamentals and current development status of various cathodic catalysts (including electrocatalysts, photoelectrocatalysts and bioelectrocatalysts) in BES, identifies their limitations and influential factors, compares their catalytic performances in terms of catalytic efficiency, stability, selectivity, etc., and discusses the possible optimization strategies and future research directions. Special focus is given on the analysis of how the catalytic performance of different catalysts can be improved by fine tuning their physicochemical or physiological properties.

  9. Catalyst mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Masel, Richard I.; Rosen, Brian A.

    2017-02-14

    Catalysts that include at least one catalytically active element and one helper catalyst can be used to increase the rate or lower the overpotential of chemical reactions. The helper catalyst can simultaneously act as a director molecule, suppressing undesired reactions and thus increasing selectivity toward the desired reaction. These catalysts can be useful for a variety of chemical reactions including, in particular, the electrochemical conversion of CO.sub.2 or formic acid. The catalysts can also suppress H.sub.2 evolution, permitting electrochemical cell operation at potentials below RHE. Chemical processes and devices using the catalysts are also disclosed, including processes to produce CO, OH.sup.-, HCO.sup.-, H.sub.2CO, (HCO.sub.2).sup.-, H.sub.2CO.sub.2, CH.sub.3OH, CH.sub.4, C.sub.2H.sub.4, CH.sub.3CH.sub.2OH, CH.sub.3COO.sup.-, CH.sub.3COOH, C.sub.2H.sub.6, O.sub.2, H.sub.2, (COOH).sub.2, or (COO.sup.-).sub.2, and a specific device, namely, a CO.sub.2 sensor.

  10. Photo-oxidation catalysts

    Science.gov (United States)

    Pitts, J. Roland; Liu, Ping; Smith, R. Davis

    2009-07-14

    Photo-oxidation catalysts and methods for cleaning a metal-based catalyst are disclosed. An exemplary catalyst system implementing a photo-oxidation catalyst may comprise a metal-based catalyst, and a photo-oxidation catalyst for cleaning the metal-based catalyst in the presence of light. The exposure to light enables the photo-oxidation catalyst to substantially oxidize absorbed contaminants and reduce accumulation of the contaminants on the metal-based catalyst. Applications are also disclosed.

  11. Long-Term Testing of Rhodium-Based Catalysts for Mixed Alcohol Synthesis – 2013 Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Gerber, Mark A.; Gray, Michel J.; Thompson, Becky L.

    2013-09-23

    The U.S. Department of Energy’s Pacific Northwest National Laboratory has been conducting research since 2005 to develop a catalyst for the conversion of synthesis gas (carbon monoxide and hydrogen) into mixed alcohols for use in liquid transportation fuels. Initially, research involved screening possible catalysts based on a review of the literature, because at that time, there were no commercial catalysts available. The screening effort resulted in a decision to focus on catalysts containing rhodium and manganese. Subsequent research identified iridium as a key promoter for this catalyst system. Since then, research has continued to improve rhodium/manganese/iridium-based catalysts, optimizing the relative and total concentrations of the three metals, examining baseline catalysts on alternative supports, and examining effects of additional promoters. Testing was continued in FY 2013 to evaluate the performance and long-term stability of the best catalysts tested to date. Three tests were conducted. A long-term test of over 2300 hr duration at a single set of operating conditions was conducted with the best carbon-supported catalyst. A second test of about 650 hr duration at a single set of operating conditions was performed for comparison using the same catalyst formulation on an alternative carbon support. A third test of about 680 hr duration at a single set of operating conditions was performed using the best silica-supported catalyst tested to date.

  12. Water-gas shift on gold catalysts: catalyst systems and fundamental studies.

    Science.gov (United States)

    Tao, Franklin Feng; Ma, Zhen

    2013-10-07

    Since the pioneering finding by Haruta et al. that small gold nanoparticles on reducible supports can be highly active for low-temperature CO oxidation, the synthesis, characterization, and application of supported gold catalysts have attracted much attention. The water-gas shift reaction (WGSR: CO + H2O = CO2 + H2) is important for removing CO and upgrading the purity of H2 for fuel cell applications, ammonia synthesis, and selective hydrogenation processes. In recent years, much attention has been paid to exploration the possibility of using supported gold nanocatalysts for WGSR and understanding the fundamental aspects related to catalyst deactivation mechanisms, nature of active sites, and reaction mechanisms. Here we summarize recent advances in the development of supported gold catalysts for this reaction and fundamental insights that can be gained, and furnish our assessment on the status of research progress.

  13. New Possibilities for development of the internal health and safety organisation

    DEFF Research Database (Denmark)

    Hasle, Peter; Jensen, Per Langå

    2004-01-01

    Research from several countries indicates that the internal health and safety organisation in most companies is placed in an appendix position. A possibility for developing a stronger and more effective health and safety organisation is to introduce learning. This approach has been applied...... in a Danish network project with eleven companies. The results indicate that health and safety managers and safety representatives have difficulties in fulfilling the role as change agents in mastering such a development project. Only three of the eleven companies turned out to be able to implement successful...

  14. High-Throughput Screening as a Supplemental Tool for the Development of Advanced Emission Control Catalysts: Methodological Approaches and Data Processing

    Directory of Open Access Journals (Sweden)

    Andreas Sundermann

    2016-01-01

    Full Text Available A high-throughput (HT screening platform developed at hte with the application focus on automotive catalysis is described. hte HT units are configured for performing steady-state testing, as well as dynamic tests with fast feed switches, such as lean/rich excursions for the evaluation of NOx storage capacity and efficiency of lean NOx traps (LNT, ammonia storage capacity for selective catalytic reduction (SCR, evaluation of oxygen storage capacity (OSC, as well as lambda sweep tests for screening of three-way catalysts (TWC. Even though catalysts are screened on a rather small scale (~100 mg powder, experience showed that dosing rather complex gas mixtures in concentrations close to that found in real exhaust for the given application is mandatory to generate relevant data. The objective of this work is to give additional insight into HT technology. In the industrial research laboratory, HT screening has matured to become a reliable approach for rapid screening of both reaction parameter spaces, as well as material properties relevant for exhaust gas catalyst development. Due to the speed of optimized screening involving 48 parallel reactors, automated handling of primary data is an imported requirement. Software for data reduction, like estimation of light-off temperature, needs to be robust and handle results for diverse sample libraries in an unattended fashion. In combination with the statistical design of experiment and multivariate data analysis, HT testing has become a valuable enhancement to automotive catalyst development.

  15. Development of Integrated TiO2 on Carburized Si Nanowires as a Catalyst/Support Structure for Alkaline Fuel Cells

    Science.gov (United States)

    Lemke, Adam J.

    Due to a combination of environmental and economic motivations, there is a strong impetus to transition away from fossil fuels towards renewable sources of energy. Critical to achieving this goal will be technologies that allow for the storage and transmission of energy derived from renewable sources. Hydrogen fuel cells may play a significant role in making this a reality, allowing for the use of hydrogen as a non-carbon based fuel, in particular for vehicle applications. Hydrogen fuel cells directly convert chemical energy into electrical energy, with only water vapor and heat as waste products. There are challenges facing fuel cell technology that inhibit its wider implementation. One of the most significant of these is the cost of the platinum that is typically used in fuel cells to catalyze the oxygen reduction reaction (ORR), which is the bottleneck reaction in hydrogen fuel cells. The rarity and expense of platinum significantly add to the cost of fuel cells, thus reducing their economic viability. Therefore there is much interest in developing catalysts from alternative materials with a lower cost. A second, and related issue facing fuel cells is the degradation over time of the support structure that puts the catalyst into electrical connection with the external load. The carbon structure that currently serves as the standard catalyst support degrades over time under the harsh operating conditions of the cell, leading to catalyst agglomeration and reducing the lifetime of the cell. It is therefore desirable to develop support structures that will be more stable, while still providing electrical conductivity. The following presents original research pertaining to the development of catalyst/support materials making use of non-noble metal oxides synthesized by means of wet chemical methods. Metal oxides such as manganese oxide and titanium oxide are capable of serving as support materials and (in the case of alkaline fuel cells) even as catalysts. Wet

  16. RS-1100柴油加氢脱硫催化剂的研制%THE DEVELOPMENT OF RS-1100 DIESEL HYDRODESULFURIZATION CATALYST

    Institute of Scientific and Technical Information of China (English)

    王锦业; 丁石; 李会峰; 王哲

    2012-01-01

    采用合适的拟薄水铝石制备氧化铝载体,并以浸渍法制备NiMo/Al2O3催化剂,找到催化剂中适宜的Ni/(Ni+ Mo)原子比,在浸渍液中引入适量的助剂和有机络合剂可以提高NiMo/Al2O3催化剂的活性.采用拉曼光谱和紫外-可见光谱仪对浸渍液进行表征,结果表明:浸渍液中存在杂多酸阴离子[P2 Mo5 O23]6-;络合剂与Ni离子也存在相互作用.通过制备条件优化,研制出高活性加氢脱硫催化剂RS-1100.中型装置评价结果表明,RS-1100催化剂的柴油超深度加氢脱硫活性比工业参比剂RS-1000更高,采用RS-1100催化剂在合适的加氢反应条件下可以生产满足欧Ⅴ排放标准的柴油.%NiMo/A1-2O3 catalyst was prepared by impregnation method using alumina support from appropriate pseudo-boehmite. The effect of Ni/(Ni + Mo) atomic ratio on the activity of NiMo/A1-2O3catalyst was investigated and optimized ratio was acquired. The activity of NiMo/A1-2O3 catalyst could be further improved by adding optimum amount of phosphorus promoter and chelating agent into the impregnation solution. The characterization of said impregnation solution by Raman spectroscopy and UV-Vis spectrophotometer showed that phosphorus-molybdenum heteropolyanions of [P2MO5O23]6- existed in the solution, besides, some interactions between chelating agent and Ni2+cations also happened. By optimizing preparation conditions, RS-1100 hydrodesulfurization catalyst with high activity was developed. The pilot-plant test results show that the activity of RS-1100 catalyst is higher than that of commercial RS-1000 catalyst at ultra-deep hydrodesulfurization stage, whereas, the bulk density of RS-1100 catalyst is lower. Diesel oil meeting European emission standard V can be produced by RS-1100 catalyst under suitable hydrogenation reaction conditions.

  17. The Possibility to Use Genetic Algorithms and Fuzzy Systems in the Development of Tutorial Systems

    Directory of Open Access Journals (Sweden)

    Anca Ioana ANDREESCU

    2006-01-01

    Full Text Available In this paper we are presenting state of the art information methods and techniques that can be applied in the development of efficient tutorial systems and also the possibility to use genetic algorithms and fuzzy systems in the construction of such systems. All this topics have been studied during the development of the research project INFOSOC entitled "Tutorial System based on Eduknowledge for Work Security and Health in SMEs According to the European Union Directives" accomplished by a teaching stuff from the Academy of Economic Studies, Bucharest, in collaboration with the National Institute for Research and Development in Work Security, the National Institute for Small and Middle Enterprises and SC Q’NET International srl.

  18. Prospects for Bioenergy Development in Ukraine and New Possibilities in the Frame of Kyoto Protocol Mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Zhovmir, N.; Geletukha, G.; Zhelyezna, T.; Matveev, Yu. [Scientific Engineering Center ' Biomass' , Kyiv (Ukraine)

    2006-07-15

    The paper analyses new possibilities for bioenergy development in Ukraine in the light of mechanisms of Kyoto protocol. There is analyzed present state of bioenergy development and future targets. Examples of successful implementation of biomass-to-energy projects and their economic indicators are given. Joint Implementation projects are the new and very promising option for the realization of biomass-to-energy projects in Ukraine. The conception of bioenergy development in Ukraine is proposed. Total energy potential of biomass in Ukraine is estimated at 12.3 Mtoe (9% of the total primary energy consumption). The most promising technologies are direct combustion of biomass for heat production, production of biogas from manure on large farms, extraction and utilization of landfill gas, co-combustion of biomass and fossil fuel for power production.

  19. Photocatalytic H{sub 2} production with CdS-based catalysts from a sulphide/sulphite substrate: an effort to develop MgO-supported catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Subrahmanyam, M.; Supriya, V.T.; Reddy, P.R. [Indian Inst. of Chemical Technology, Hyderabad (India). Catalysis Section

    1996-02-01

    CdS-based photocatalysts supported on MgO and {gamma}-Al{sub 2}O{sub 3} have been prepared, characterized and tested for dihydrogen evolution from a sulphide/sulphite substrate using a halogen lamp source. The effect of precursor salt for CdS preparation, the optimum loading of CdS on the support and the concentration of the catalyst in 50 ml of solution have been investigated. The effect of adding to CdS a semiconductor ZnS-Ag{sub 2}S and catalytic materials like Pt and RuO{sub 2} have also been studied. The results obtained from the basic nature of MgO support are compared with the acidic nature of Al{sub 2}O{sub 3} support. The importance of the acid-base properties of the support is substantiated by modifying the Al{sub 2}O{sub 3} support with base materials like CaO/BaO. Thus, the effect of the acid-base properties of the supports is highlighted. (author)

  20. OPEN FLEXIBLE LIFELONG LEARNING AS A CATALYST FOR SUSTAINABLE DEVELOPMENT IN SUB-SAHARAN AFRICA

    OpenAIRE

    OLAKULEHIN, Felix Kayode

    2010-01-01

    Educational provision in developing sub-Saharan Africa states has been severely hindered by the hydra-headed problems of access, cost and quality. Amidst these challenges is the pledge of regional and national education policymakers and development planners to ensure that there is maximum access equitable and qualitative education for all (EFA) in Africa. There is also a burning need for improved literacy levels and functional education, in order to overcome the development deficits that are ...

  1. Prospects of Waterway Development as a Catalyst to Improve Regional and Community Socio-Economy Level

    OpenAIRE

    Sulaiman M. Yassin; Hayrol A.M. Shaffril; Md. S. Hassan; Mohd S. Othman; Asnarulkhadi A. Samah; Bahaman A. Samah

    2010-01-01

    Problem statement: Malaysia has achieved a number of successes in its transportation development. The success of Kuala Lumpur International Airport and Northern and Southern Highway project for examples have given the community lot of benefits in term of social and economic development, but what if an inland waterway system can be developed in Malaysia especially along Pahang River and Muar River. Can this proposed waterway bring significant impact to local people in term of their social and ...

  2. Highly dispersed metal catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Xin; West, William L.; Rhodes, William D.

    2016-11-08

    A supported catalyst having an atomic level single atom structure is provided such that substantially all the catalyst is available for catalytic function. A process of forming a single atom catalyst unto a porous catalyst support is also provided.

  3. Open Flexible Lifelong Learning as a Catalyst for Sustainable Development in Sub-Saharan Africa

    Science.gov (United States)

    Olakulehin, Felix Kayode

    2010-01-01

    Educational provision in developing sub-Saharan Africa states has been severely hindered by the hydra-headed problems of access, cost and quality. Amidst these challenges is the pledge of regional and national education policymakers and development planners to ensure that there is maximum access equitable and qualitative education for all (EFA) in…

  4. Development of precipitated iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 July 1995--30 September 1995

    Energy Technology Data Exchange (ETDEWEB)

    Bukur, D.B.

    1995-12-20

    The following accomplishments were made on task 4. Reproducibility of Catalyst Preparation: (1) Five slurry reactor tests were completed. Three tests were conducted using catalyst C (100 Fe/3 Cu/4 K/16 SiO{sub 2}) from three different batches (runs SB-2695, SB-2145 and SA-2715), and two tests were conducted with catalyst B (100 Fe/5 Cu/6 K/24 SiO{sub 2}) from two different preparation batches (runs SA-2615 and SB-2585). Performance of catalysts from different batches (activity, selectivity and deactivation rates) was similar to that of catalysts from the original batch (synthesized during DOE Contract DE- AC22-89PC89868). Thus, another major objective of the present contract, demonstration of reproducibility of catalyst preparation procedure and performance, has been accomplished. With these tests the work on Task 4 has been successfully completed. Two fixed bed reactor tests of catalysts B and C synthesized using potassium silicate solution as the source of potassium promoter were completed during this period (Task 5. The Effect of Source of Potassium and Basic Oxide Promoter). Activity of catalysts prepared using potassium silicate as the source of potassium promotion was somewhat higher, and their methane selectivities were higher than those of the corresponding catalysts prepared by incipient wetness impregnation using KHCO{sub 3} as the source of potassium promoter. However, these differences were not large, and may have been caused by experimental artifacts (e.g. existence of local hot spots in a reactor). A slurry reactor test (SA-2405) of catalyst with nominal composition 100 Fe/5 Cu/2 Ca/24 SiO{sub 2} was completed (Task 5). In general, the catalyst activity, space-time-yield, and hydrocarbon selectivities in this run during testing at:260{degrees}C, 2.17 MPa (300 psig), 2-2.6 Nl/g-cat/h and H{sub 2}CO=0.67 were quite good, and comparable to the best results obtained in our Laboratory.

  5. Possible development mechanisms of pre-monsoon thunderstorms over northeast and east India

    Science.gov (United States)

    Narayanan, Sunanda; Vishwanathan, Gokul; Mrudula, G.

    2016-05-01

    Thunderstorms are mesoscale convective systems of towering cumulonimbus clouds of high vertical and horizontal extent lasting from a few minutes to several hours. Pre-monsoon thundershowers over the past 10 years have been analyzed to understand the organization, horizontal and vertical development and dissipation of such severe events. Kalbaisakhi's/ Norwester's over north east and East India is given preference in this study, while some of the other extreme events are also analyzed due to their severity. The meteorological parameters like horizontal and vertical wind, precipitable water etc., and derived variables such as Severe Weather Threat (SWEAT) Index, Convective Available Potential Energy (CAPE), and Convective Inhibition Energy (CINE) of the identified cases are analyzed using observations from NCEP and IMD. Satellite observations from IMD and TRMM are also used to analyze the development and moisture flow of such systems. The analysis shows that some of the parameters display a clear signature of developing thunderstorms. It is also seen that cloud parameters such as convective precipitation rate and convective cloud cover from NCEP FNL didn't show much variation during the development of storms, which may be attributed to the limitation of spatial and temporal resolution. The parameters which showed indications of a developing thunderstorm were studied in detail in order to understand the possible mechanisms behind the development and organization of thunderstorm cells.

  6. Follow the Yellow Brick Road: Websites as Catalysts for National Development

    Directory of Open Access Journals (Sweden)

    Pearson Broome

    2015-06-01

    Full Text Available Small-island developing states (SIDS enhance their competitiveness by advertising development initiatives that promote and encourage direct foreign inward investment opportunities in major markets. Failure to make use of information communication technologies (ICTs can undermine national development initiatives with transformative potential. Based on this logic, some Caribbean governments have followed international best practices of businesses and have moved towards the creation of websites and the establishment of portals or gateway sites on the World Wide Web to announce their presence.  One of the practical implications of such initiatives is based on the assumption that once websites are built, persons will come. Although for many, the development of a website appears to be an innocuous endeavour this mistaken perception in most cases has led to several sites being designed and commissioned as technical projects mostly employing techno-centric approaches. These policies often ignore the accompanying important socio-technical institutional considerations, such as the importance of timely and accurate information to potential business clients or prospective developers, language capabilities, and a range of standards, guidelines, rules and legislative changes. The central thesis of this conceptual paper is that if member states of the region properly conceptualise and design websites and portals they can be used to achieve strategic national and international development objectives of egovernance in its broadest meaning. The arguments are intended to stimulate thought among policy makers and the private sector alike in the Caribbean with a view to bringing about change that will promote sustainable development.

  7. RSC-2006催化剂的研发及工业应用%The Development and Industrial Application of RSC-2006 Catalyst

    Institute of Scientific and Technical Information of China (English)

    刘汉坡

    2016-01-01

    RSC-2006 catalyst,which is developed by SINOPEC Research Institute of Petroleum Processing and produced by SINOPEC Catalyst Co.,Ltd.Qilu Division,has been successfully applied in the HOFCC unit of SINOPEC Jingmen Petrochemical. RSC-2006 catalyst shows excellent heavy oil converting ability and coke selectivity.The industrial application of RSC-2006 catalyst has brought considerable economic benefits to SINOPEC Jingmen Petrochemical.%由中国石油化工股份有限公司石油化工科学研究院研制、齐鲁催化剂分公司生产的RSC-2006催化剂在荆门重油催化裂化装置上进行了成功的工业应用。RSC-2006催化剂具有优异的重油转化能力和焦炭选择性,RSC-2006催化剂的工业应用为荆门分公司带来了可观的经济效益。

  8. Development of a catalyst for conversion of syngas-derived materials to isobutylene. Quarterly report number 19, October 1--December 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Spehlmann, B.C.

    1996-07-01

    The goals of this project are to develop a catalyst and process for the conversion of syngas to isobutanol. After identification and optimization of key catalyst and process characteristics, the commercial potential of the process is to be evaluated by an economic analysis. From independent process variable studies to investigate the conversion of a methanol/ethanol feed to isobutanol, the best performance to date has been achieved with the 2% Pt on Zn/Mn/Zr oxide catalyst. Using Hyprotech Hysim v2.5 process simulation software, and considering both gas and liquid recycle loops in the process flow diagram, the overall carbon conversion is 98% with 22% selectivity to isobutanol. The expected production of isobutanol is 92 MT/day from 500 MT/day of methanol and 172 MT/day of ethanol feed. An additional 13 MT/day of isobutryaldehyde intermediate is recovered in the liquid product and vent streams. Because of the low selectivity (22%) of the methanol conversion catalyst to isobutanol, the process is uneconomical, even if the isobutanol is valued as a solvent ($903/MT) and not as isobutylene for MTBE production ($352/MT).

  9. New developments in ground probing radar: the possibility of reconstructing a holographic image of underground reflectivity

    Directory of Open Access Journals (Sweden)

    L. Sambuelli

    2000-06-01

    Full Text Available During the last decade GPR has developed rapidly: instruments have become more compact and more digital, the field of application has broadened from non-destructive testing to humanitarian demining. Studies have been carried out to analyse the full information content of the backscattered wavefield trying to go beyond the time and amplitude analysis. In recent years, many researchers have focused on the possibility of applying holographic acquisition and processing to GPR data. This paper proposes a theoretical outline of a holographic acquisition and processing techniques; a block diagram of the proposed holographic radar; the outlines of the design and the realisation of a custom-built full-scale test-site and the results of the first simulations carried out with newly developed software. The basic rules for an optimum choice of the main acquisition parameters are also given together with a discussion of the main advantages and disadvantages of the proposed techniques.

  10. OPEN FLEXIBLE LIFELONG LEARNING AS A CATALYST FOR SUSTAINABLE DEVELOPMENT IN SUB-SAHARAN AFRICA

    Directory of Open Access Journals (Sweden)

    Felix Kayode OLAKULEHIN

    2010-10-01

    Full Text Available Educational provision in developing sub-Saharan Africa states has been severely hindered by the hydra-headed problems of access, cost and quality. Amidst these challenges is the pledge of regional and national education policymakers and development planners to ensure that there is maximum access equitable and qualitative education for all (EFA in Africa. There is also a burning need for improved literacy levels and functional education, in order to overcome the development deficits that are currently facing the region. The pledge of education for all resonates the agreement which representatives of several nations of the world signed at the Jomtien summit on Education for All and the subsequent evaluation meetings. Following this pledge, several developing, sub-Sahara African nations have evolved initiatives for instituting sustainable Open Flexible Learning (ODL systems in order to meet up with the seemingly intractable EFA objectives. This paper examined the potential impact of these OFL initiatives on the achievement of the EFA objectives which is seen as the basis of development planning, administration and implementation in Africa. It identified the various challenges confronting effective implementation of ODL on the continent, amidst the need to expand access to educational opportunities. An attempt was made to situate the OFL system at the centre of the strategies for achieving these EFA objectives in the region and finally, a proposal for sustainable policy initiatives for implementing OFL systems for the attainment of education for all in Africa is made.

  11. Heterogeneous Catalysts

    NARCIS (Netherlands)

    Dakka, J.; Sheldon, R.A.; Sanderson, W.A.

    1997-01-01

    Abstract of GB 2309655 (A) Heterogeneous catalysts comprising one or more metal compounds selected from the group consisting of tin, molybdenum, tungsten, zirconium and selenium compounds deposited on the surface of a silicalite are provided. Preferably Sn(IV) and/or Mo(VI) are employed. The cat

  12. Academic Programmes in Universities in East Africa: A Catalyst to Development

    Science.gov (United States)

    Karimi, Florah Katanu

    2015-01-01

    The types of academic programmes offered by universities, both public and private, are considered to be critical to the realization of development agendas. This study was descriptive in nature and sought to establish whether universities in the East African region were offering academic programmes that were relevant to the realization of the…

  13. Possible Effect of 30K Proteins in Embryonic Development of Silkworm Bombyx mori

    Institute of Scientific and Technical Information of China (English)

    Bo-Xiong ZHONG; Jian-Ke LI; Jian-Rong LIN; Jian-She LIANG; Song-Kun SU; Hai-Sheng XU; Hai-Yan YAN; Ping-Bo ZHANG; Hiroshi FUJII

    2005-01-01

    The silkworm Bombyx mori possesses a 30K protein family of 3×104 Da, the biological functions of which have not been fully identified. The relationship between the 30K protein family and the embryonic development of temperature sensitive sex-linked mutant strain of silkworm was investigated by two dimensional polyacrylamide gel electrophoresis (2D-PAGE) and Matrix assisted laser desorption ionizationtime of flight mass spectrometry (MALDI-TOF MS). The results show that protein spots 1-5 of the 30K protein family, mainly existing in normal strain, are possibly related to embryonic development. The early consumption of a 30K protein named 6G1-30K-1 and the accumulation of 30K proteins named 6G1-30K-3and 6G 1-30K-4 are likely caused by the destruction of physiological balance in normal embryonic development,which may lead to lower hatchability of the temperature sensitive strain. The results suggest that reasonable metabolism of 30K proteins is a prerequisite for the embryo's normal development.

  14. Civil society: the catalyst for ensuring health in the age of sustainable development.

    Science.gov (United States)

    Smith, Julia; Buse, Kent; Gordon, Case

    2016-07-16

    Sustainable Development Goal Three is rightly ambitious, but achieving it will require doing global health differently. Among other things, progressive civil society organisations will need to be recognised and supported as vital partners in achieving the necessary transformations. We argue, using illustrative examples, that a robust civil society can fulfill eight essential global health functions. These include producing compelling moral arguments for action, building coalitions beyond the health sector, introducing novel policy alternatives, enhancing the legitimacy of global health initiatives and institutions, strengthening systems for health, enhancing accountability systems, mitigating the commercial determinants of health and ensuring rights-based approaches. Given that civil society activism has catalyzed tremendous progress in global health, there is a need to invest in and support it as a global public good to ensure that the 2030 Agenda for Sustainable Development can be realised.

  15. Ceramics in Environmental Catalysis:Applications and Possibilities%Ceramics in Environmental Catalysis: Applications and Possibilities

    Institute of Scientific and Technical Information of China (English)

    Nitin LABHSETWAR; P.DOGGALI; S.RAYALU; R.YADAV; T.MISTUHASHI; H.HANEDA

    2012-01-01

    Environmental catalysis has been steadily growing because of the advances in its scientific and engineering aspects,as well as due to the new environmental challenges in the industrial era.The development of new catalysts and materials is essential for new technologies for various environmental applications.Ceramics play important roles in various environmental applications including the identification,monitoring,and quantification of pollutants and their control.Ceramics have important applications as sensors and photocatalysts,and they are extensively used as catalyst carriers and supports.Many ceramics are being explored as catalysts for pollution control applications.Their low cost,thermal and chemical stability,and capability of being tailored make them especially attractive for pollution control applications.Although a wide variety of materials have been developed as catalyst supports,this area is still of interest with new or modified catalyst supports being frequently reported.It is of equal importance to develop new or modified processes for the loading of catalysts on specific supports.Applications like chemical looping combustion (CLC) and other catalytic combustion processes are raising the demands to a new scale.We have been working on the development of both new and modified support materials,including mesoporous materials without structural order for possible applications in CLC and other catalytic reactions.Successful attempts have been made in the modification of conventional γ-Al2O3 and improved synthesis processes for supporting perovskite type catalysts.Our research on environmental catalysis applications of ceramic materials and processes are also briefly discussed.

  16. Cystatin C and lactoferrin concentrations in biological fluids as possible prognostic factors in eye tumor development

    Directory of Open Access Journals (Sweden)

    Mariya A. Dikovskaya

    2013-08-01

    Full Text Available Objectives. To investigate the possible role of cystatin C in eye biological fluids locally and in serum and lactoferrin revealing anti-tumor activity in eye tumor development. Background. The increased number of eye tumors was registered recently not only in the countries with high insolation, but also in the northern countries including Russia (11 cases per million of population. Search for new biological markers is important for diagnosis and prognosis in eye tumors. Cystatin C, an endogenous inhibitor of cysteine proteases, plays an important protective role in several tumors. Lactoferrin was shown to express anti-tumor and antiviral activities. It was hypothesized that cystatin C and lactoferrin could serve as possible biomarkers in the diagnosis of malignant and benign eye tumors. Study design. A total of 54 patients with choroidal melanoma and benign eye tumors were examined (part of them undergoing surgical treatment. Serum, tear fluid and intraocular fluid samples obtained from the anterior chamber of eyes in patients with choroidal melanoma were studied. Methods. Cystatin C concentration in serum and eye biological fluids was measured by commercial ELISA kits for human (BioVendor, Czechia; lactoferrin concentration – by Lactoferrin-strip D 4106 ELISA test systems (Vector-BEST, Novosibirsk Region, Russia. Results. Cystatin C concentration in serum of healthy persons was significantly higher as compared to tear and intraocular fluids. In patients with choroidal melanoma, increased cystatin C concentration was similar in tear fluid of both the eyes. Lactoferrin level in tear fluid of healthy persons was significantly higher than its serum level. Significantly increased lactoferrin concentration in tear fluid was noted in patients with benign and malignant eye tumors. Conclusion. Increased level of cystatin C in tear fluid seems to be a possible diagnostic factor in the eye tumors studied. However, it does not allow us to differentiate

  17. DEVELOPMENT OF MULTI-TASK CATALYSTS FOR REMOVAL OF NOx AND TOXIC ORGANIC COMPOUNDS DURING COAL COMBUSTION

    Energy Technology Data Exchange (ETDEWEB)

    Panagiotis G. Smirniotis; Robert G. Jenkins

    2002-02-04

    The work performed during this project focused on the identification of materials capable of providing high activity and selectivity for the selective catalytic reduction of nitric oxide with ammonia. The material surface characteristics were correlated with the catalytic behavior of our catalysts to increase our understanding and to help improve the DeNO{sub x} efficiency. The catalysts employed in this study include mixed oxide composite powders (TiO{sub 2}-Cr{sub 2}O{sub 3}, TiO{sub 2}-ZrO{sub 2}, TiO{sub 2}-WO{sub 3}, TiO{sub 2}-SiO{sub 2}, and TiO{sub 2}-Al{sub 2}O{sub 3}) loaded with varying amounts of V{sub 2}O{sub 5}, along with 5 different commercial sources of TiO{sub 2}. V{sub 2}O{sub 5} was added to the commercial sources of TiO{sub 2} to achieve monolayer coverage. Since the valence state of vanadium in the precursor solution during the impregnation step significantly impacted catalytic performance, catalysts were synthesized from both V{sup +4} and V{sup +5} solutions explain this phenomenon. Specifically, the synthesis of catalysts from V{sup 5+} precursor solutions yields lower-performance catalysts compared to the case of V{sup 4+} under identical conditions. Aging the vanadium precursor solution, which is associated with the reduction of V{sup 5+} to V{sup 4+} (VO{sub 2}{sup +} {yields} VO{sup 2+}), prior to impregnation results in catalysts with excellent catalytic behavior under identical activation and operating conditions. This work also added vanadia to TiO{sub 2}-based supports with low crystallinity. These supports, which have traditionally performed poorly, are now able to function as effective SCR catalysts. Increasing the acidity of the support by incorporating oxides such as WO{sub 3} and Al{sub 2}O{sub 3} significantly improves the SCR activity and nitrogen selectivity. It was also found that the supports should be synthesized with the simultaneous precipitation of the corresponding precursors. The mixed oxide catalysts possess

  18. Development of Pd and Pd-Co catalysts supported on multi-walled carbon nanotubes for formic acid oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Morales-Acosta, D.; Godinez, Luis A.; Rodriguez, H.G.; Arriaga, L.G. [Centro de Investigacion y Desarrollo Tecnologico en Electroquimica, Parque Tecnologico Queretaro, Sanfandila, Pedro Escobedo, C.P. 76703 Queretaro (Mexico); Ledesma-Garcia, J. [Division de Investigacion y Posgrado, Facultad de Ingenieria, Universidad Autonoma de Queretaro, Cerro de las Campanas S/N, C.P. 76010, Queretaro, Qro. (Mexico); Alvarez-Contreras, L. [Centro de Investigacion en Materiales Avanzados S. C., Complejo Industrial Chihuahua, C.P. 31109, Chihuahua, Chih. (Mexico)

    2010-01-15

    Pd-Co and Pd catalysts were prepared by the impregnation synthesis method at low temperature on multi-walled carbon nanotubes (MWCNTs). The nanotubes were synthesized by spray pyrolysis technique. Both catalysts were obtained with high homogeneous distribution and particle size around 4 nm. The morphology, composition and electrocatalytic properties were investigated by transmission electron microscopy, scanning electron microscopy-energy dispersive X-ray analysis, X-ray diffraction and electrochemical measurements, respectively. The electrocatalytic activity of Pd and PdCo/MWCNTs catalysts was investigated in terms of formic acid electrooxidation at low concentration in H{sub 2}SO{sub 4} aqueous solution. The results obtained from voltamperometric studies showed that the current density achieved with the PdCo/MWCNTs catalyst is 3 times higher than that reached with the Pd/MWCNTs catalyst. The onset potential for formic acid electrooxidation on PdCo/MWCNTs electrocatalyst showed a negative shift ca. 50 mV compared with Pd/MWCNTs. (author)

  19. Possible contribution of(pro)renin receptor to development of gestational diabetes mellitus

    Institute of Scientific and Technical Information of China (English)

    Kanako; Bokuda; Atsuhiro; Ichihara

    2014-01-01

    (Pro)renin receptor [(P)RR], a receptor for renin and prorenin, was first cloned in 2002. Since then, the pathophysiological roles of(P)RR have been growing concerns.(P)RR binds renin and prorenin, with two important consequences, nonproteolytic activation of prorenin, leading to the tissue renin-angiotensin system activation and the intracellular signalings. It is now also known to play an important role as vacuolar H+-ATPase associated protein, involving in Wnt signaling, main component of embryonic development. Extracellular domain of full-length(P)RR is cleaved in golgi-complex forming soluble(P)RR [s(P)RR]. The s(P)RR is now possible to be measured in human blood and urine. It is now measured in different pathophysiological states, and recent study showed that elevated plasma s(P)RR levels in the early stage of pregnancies are associated with higher incidence of gestational diabetes mellitus later in the pregnancies. Plasma s(P)RR levels of neonates are known to be higher than that of adults. It was also shown that, increased s(P)RR concentrations in cord blood, associated with a lower small for gestational age birth likelihood. These data suggests the involvement of(P)RR in embryo’s growth. In thisreview article, we attempt to figure out the possible pathophysiological roles of the(P)RR in maternal glucose intolerance and embryo’s growth, through reviewing previous studies.

  20. Development of a complete kinetic model for the Fischer-Tropsch synthesis over Co/Al{sub 2}O{sub 3} catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Visconti, C.G.; Tronconi, E.; Lietti, L.; Forzatti, P. [Politecnico di Milano (Italy). Dipt. di Chimica, Materiali e Ingegneria Chimica ' ' G.Natta' ' ; Zennaro, R. [EniTecnologie, San Donato Milanese (Italy). Catalysis and Process Technology Research Centre

    2006-07-01

    A global kinetic model of the FTS over a Co/Al{sub 2}O{sub 3} state-of-the-art catalyst is developed in a fixed bed micro-reactor under conditions relevant to industrial operation (temperature, 210- 235 C; pressure, 8-25 bar; H{sub 2}/CO feed molar ratio, 1.8-2.7; gas hourly space velocity, 2000- 7000 cm{sup 3}(STP)/h/g{sub catalyst}). On the basis of proposed reaction mechanisms, developed according to the carbide theory and the alkyl mechanism, the kinetic expressions for n-paraffins and {alpha}-olefins formation are derived. Both the calculated CO conversion and the hydrocarbons distribution (up to N=49) in FTS reaction are satisfactorily predicted. (orig.)

  1. Possibility of Preparing Thematic Maps Through Developing of the Geographic Information System (GIS

    Directory of Open Access Journals (Sweden)

    Stjepan Husnjak

    2013-04-01

    Full Text Available It is a well known fact that nowadays planning of sustainable development and land use requires a lot of reliable and good quality information, which serves as the basis for timely and adequate decision-making. One of the most important forms of information is presented in various maps. Until recently, preparing of such data was, no doubt, a rather complex and time-consuming task. However, at present, thanks to, first of all, the GIS technology it is possible to develop corresponding geographic information systems with databases which then allow comparatively simple and quick preparing of necessary thematic maps. The paper first presents the method of developing the Geographic and Land Information System (GLIS of the Karlovac County which, although developed for the purpose of agricultural development, may also be used in the development of forestry, environment protection, physical planning, water management and for soil conservation and regulation. Several examples illustrate the possibilities of preparing of specialised maps based on this GLIS. The basic data for developing of the geographic and land information system were the data of the Basic Soil Maps and topographic maps of the Republic of Croatia at the scale of 1:50 000 or 1:25 000, and the data from other studies made for the purpose of agricultural development in the area. These data, together with the results of processing and analysing of this data, by digitalisation, generalisation and interpolation, were incorporated into an integrated database of the geographic and land information system by using Microstation, AutoCad, ArcInfo, ArcWiew and Access software and the corresponding hardware. GLIS database consists of two parts. The first part includes the data referring to polygons - pedological contours, and the other part the data on pedological profiles. The base is organised in a way that enable the preparation of different thematic maps, but it can be also used in digital form

  2. Possible action mechanism of the electromagnetic fields in the liver cancer development: A mathematical proposal

    Energy Technology Data Exchange (ETDEWEB)

    Jiménez-García, Mónica Noemí [Departamento de Física, Centro de Investigación y de Estudios Avanzados del IPN, Apdo. Postal 14-740, 07000, México D.F (Mexico); Godina-Nava, Juan José [Departamento de Física, Centro de Investigación y de Estudios Avanzados del IPN, Apdo. Postal 14-740, 07000, México (Mexico)

    2012-02-08

    Currently it is known that electromagnetic field exposure can induce biological changes, although the precise effects and action mechanism of the interaction between the electromagnetic field and biological systems are not well understood. In this work we propose a possible action mechanism, concerning the effect that the extremely low frequency electromagnetic field exposure has on the early stage of liver cancer development. The model is developed studying the phenomena called oxidative stress that it appears after it is applied a carcinogenic agent used to induce hepatic cancer chemically in an experimental animal model. This physical-chemical process involves the movement of magnetic field dependent free charged particles, called free radicals. We will consider the use of the radical pairs theory as a framework, in which we will describe the spin density operator evolution by implementing the stochastic Liouville equation with hyperfine interaction. This describes how the selectivity of the interaction between spin states of the free radicals with the applied electromagnetic field, influences the development of pre-neoplastic lesions in the liver. AIP Publishing is retracting this article due to the substantial use of content in the Results and Conclusions section without proper citation of a previously published paper in Chemical Physics Letters 361 (2012) 219-225. This article is retracted from the scientific record with effect from 15 October 2015.

  3. Possible action mechanism of the electromagnetic fields in the liver cancer development: A mathematical proposal

    Science.gov (United States)

    Jiménez-García, Mónica Noemí; Godina-Nava, Juan José

    2012-02-01

    Currently it is known that electromagnetic field exposure can induce biological changes, although the precise effects and action mechanism of the interaction between the electromagnetic field and biological systems are not well understood. In this work we propose a possible action mechanism, concerning the effect that the extremely low frequency electromagnetic field exposure has on the early stage of liver cancer development. The model is developed studying the phenomena called oxidative stress that it appears after it is applied a carcinogenic agent used to induce hepatic cancer chemically in an experimental animal model. This physical-chemical process involves the movement of magnetic field dependent free charged particles, called free radicals. We will consider the use of the radical pairs theory as a framework, in which we will describe the spin density operator evolution by implementing the stochastic Liouville equation with hyperfine interaction. This describes how the selectivity of the interaction between spin states of the free radicals with the applied electromagnetic field, influences the development of pre-neoplastic lesions in the liver. AIP Publishing is retracting this article due to the substantial use of content in the Results and Conclusions section without proper citation of a previously published paper in Chemical Physics Letters 361 (2012) 219-225. This article is retracted from the scientific record with effect from 15 October 2015.

  4. Utilizing inter-organizational relationships for new product development performance: A test of possible mediation effects

    DEFF Research Database (Denmark)

    Mortensen, Thomas Bøtker; Knudsen, Mette Præst

    The purpose of this paper is to investigate whether collaborative experience can act as a mediating variable on the use of inter-organizational relationships on NPD performance. The paper tests two different research questions: 1) Is there a possible mediating effect of experience on the linkage...... in networks and not in solitude and should therefore be strategic about who to include in e.g. product development projects and how much to include the selected partners in the projects. A growing literature has concluded that trust and experience are vital tacit skills to build, which may be crucial...... in establishing successful relationships. However, the empirical evidence reported in the literature is still relatively scarce. This paper therefore aims at testing the role of previous experience and norms for sharing knowledge with partners for successful collaborative ventures especially regarding NPD...

  5. Global value chains and agrifood standards: challenges and possibilities for smallholders in developing countries.

    Science.gov (United States)

    Lee, Joonkoo; Gereffi, Gary; Beauvais, Janet

    2012-07-31

    The rise of private food standards has brought forth an ongoing debate about whether they work as a barrier for smallholders and hinder poverty reduction in developing countries. This paper uses a global value chain approach to explain the relationship between value chain structure and agrifood safety and quality standards and to discuss the challenges and possibilities this entails for the upgrading of smallholders. It maps four potential value chain scenarios depending on the degree of concentration in the markets for agrifood supply (farmers and manufacturers) and demand (supermarkets and other food retailers) and discusses the impact of lead firms and key intermediaries on smallholders in different chain situations. Each scenario is illustrated with case examples. Theoretical and policy issues are discussed, along with proposals for future research in terms of industry structure, private governance, and sustainable value chains.

  6. Blended Learning Possibilities in Enhancing Education, Training and Development in Developing Countries: A Case Study in Graphic Design Courses

    Directory of Open Access Journals (Sweden)

    Hanan Atef

    2015-11-01

    Full Text Available Blended learning is not a new concept; recently, there has been a renewed focus on this learning strategy, both in the education and corporate sectors. Although the definition of blended learning is somewhat inchoate, it is generally described as an environment that includes the use of different modes of teaching and learning. Blended learning holds particular promise for developing countries because it can make availability of resources, regional, and international educational institutions. The perspective we adopt in this paper, where we aim to take a realistic look at the potential of blended learning in developing countries, giving consideration to the various possibilities and most importantly, to the accessibility of technology both today and in the future.

  7. The innovation catalysts.

    Science.gov (United States)

    Martin, Roger L

    2011-06-01

    A few years ago the software development company Intuit realized that it needed a new approach to galvanizing customers. The company's Net Promoter Score was faltering, and customer recommendations of new products were especially disappointing. Intuit decided to hold a two-day, off-site meeting for the company's top 300 managers with a focus on the role of design in innovation. One of the days was dedicated to a program called Design for Delight. The centerpiece of the day was a PowerPoint presentation by Intuit founder Scott Cook, who realized midway through that he was no Steve Jobs: The managers listened dutifully, but there was little energy in the room. By contrast, a subsequent exercise in which the participants worked through a design challenge by creating prototypes, getting feedback, iterating, and refining, had them mesmerized. The eventual result was the creation of a team of nine design-thinking coaches--"innovation catalysts"--from across Intuit who were made available to help any work group create prototypes, run experiments, and learn from customers. The process includes a "painstorm" (to determine the customer's greatest pain point), a "soljam" (to generate and then winnow possible solutions), and a "code-jam" (to write code "good enough" to take to customers within two weeks). Design for Delight has enabled employees throughout Intuit to move from satisfying customers to delighting them.

  8. Mechanical pain sensitivity of deep tissues in children - possible development of myofascial trigger points in children

    Directory of Open Access Journals (Sweden)

    Han Ting-I

    2012-02-01

    Full Text Available Abstract Background It is still unclear when latent myofascial trigger points (MTrPs develop during early life. This study is designed to investigate the mechanical pain sensitivity of deep tissues in children in order to see the possible timing of the development of latent MTrPs and attachment trigger points (A-TrPs in school children. Methods Five hundreds and five healthy school children (age 4- 11 years were investigated. A pressure algometer was used to measure the pressure pain threshold (PPT at three different sites in the brachioradialis muscle: the lateral epicondyle at elbow (site A, assumed to be the A-TrP site, the mid-point of the muscle belly (site B, assumed to be the MTrP site, and the muscle-tendon junction as a control site (site C. Results The results showed that, for all children in this study, the mean PPT values was significantly lower (p p Conclusions It is concluded that a child had increased sensitivity at the tendon attachment site and the muscle belly (endplate zone after age of 4 years. Therefore, it is likely that a child may develop an A-Trp and a latent MTrP at the brachioradialis muscle after the age of 4 years. The changes in sensitivity, or the development for these trigger points, may not be related to the activity level of children aged 7-11 years. Further investigation is still required to indentify the exact timing of the initial occurrence of a-Trps and latent MTrPs.

  9. Possible involvement of leptin and leptin receptor in developing gastric adenocarcinoma

    Institute of Scientific and Technical Information of China (English)

    Liang Zhao; Zhi-Xiang Shen; He-Sheng Luo; Lei Shen

    2005-01-01

    AIM: To investigate the expression of leptin and leptin receptor (ob-R) in intestinal-type gastric cancer and precancerous lesions, and to explore the possible mechanism and role of the leptin system in developing intestinal-type gastric adenocarcinoma.METHODS: Immunohistochemistry was performed to examine the expression of leptin and leptin receptor in archival samples of gastric adenocarcinoma and preneoplastic lesions, including intestinal metaplasia and mild to severe gastric epithelial dysplasia. Positive staining was identified and percentage of positive staining was graded.RESULTS: Dual expression of leptin and leptin receptor were detected in 80% (16/20) intestinal metaplasia,86.3% (25/30) mild gastric epithelial dysplasia, 86.7%(26/30) moderate gastric epithelial dysplasia, 93.3%(28/30) severe gastric epithelial dysplasia, 91.3% (55/60)intestinal-type gastric adenocarcinoma and 30.0% (9/30)difffuse-type gastric carcinoma. The percentage of dual expression of leptin and leptin receptor in intestinal-type gastric adenocarcinoma was significantly higher than that in diffuse-type gastric adenocarcinoma (x2 = 37.022,P<0.01).CONCLUSION: Our results indicate the presence of an autocrine loop of leptin system in the development of intestinal-type gastric adenocarcinoma.

  10. Highly Dispersed Alloy Catalyst for Durability

    Energy Technology Data Exchange (ETDEWEB)

    Murthi, Vivek S.; Izzo, Elise; Bi, Wu; Guerrero, Sandra; Protsailo, Lesia

    2013-01-08

    Achieving DOE's stated 5000-hr durability goal for light-duty vehicles by 2015 will require MEAs with characteristics that are beyond the current state of the art. Significant effort was placed on developing advanced durable cathode catalysts to arrive at the best possible electrode for high performance and durability, as well as developing manufacturing processes that yield significant cost benefit. Accordingly, the overall goal of this project was to develop and construct advanced MEAs that will improve performance and durability while reducing the cost of PEMFC stacks. The project, led by UTC Power, focused on developing new catalysts/supports and integrating them with existing materials (membranes and gas diffusion layers (GDLs)) using state-of-the-art fabrication methods capable of meeting the durability requirements essential for automotive applications. Specifically, the project work aimed to lower platinum group metals (PGM) loading while increasing performance and durability. Appropriate catalysts and MEA configuration were down-selected that protects the membrane, and the layers were tailored to optimize the movements of reactants and product water through the cell to maximize performance while maintaining durability.

  11. Agricultural biotechnologies in developing countries and their possible contribution to food security.

    Science.gov (United States)

    Ruane, John; Sonnino, Andrea

    2011-12-20

    Latest FAO figures indicate that an estimated 925 million people are undernourished in 2010, representing almost 16% of the population in developing countries. Looking to the future, there are also major challenges ahead from the rapidly changing socio-economic environment (increasing world population and urbanisation, and dietary changes) and climate change. Promoting agriculture in developing countries is the key to achieving food security, and it is essential to act in four ways: to increase investment in agriculture, broaden access to food, improve governance of global trade, and increase productivity while conserving natural resources. To enable the fourth action, the suite of technological options for farmers should be as broad as possible, including agricultural biotechnologies. Agricultural biotechnologies represent a broad range of technologies used in food and agriculture for the genetic improvement of plant varieties and animal populations, characterisation and conservation of genetic resources, diagnosis of plant or animal diseases and other purposes. Discussions about agricultural biotechnology have been dominated by the continuing controversy surrounding genetic modification and its resulting products, genetically modified organisms (GMOs). The polarised debate has led to non-GMO biotechnologies being overshadowed, often hindering their development and application. Extensive documentation from the FAO international technical conference on Agricultural Biotechnologies in Developing Countries (ABDC-10), that took place in Guadalajara, Mexico, on 1-4 March 2010, gave a very good overview of the many ways that different agricultural biotechnologies are being used to increase productivity and conserve natural resources in the crop, livestock, fishery, forestry and agro-industry sectors in developing countries. The conference brought together about 300 policy-makers, scientists and representatives of intergovernmental and international non

  12. Efficient Nd Promoted Rh Catalysts for Vapor Phase Methanol Carbonylation

    Institute of Scientific and Technical Information of China (English)

    Shu Feng ZHANG; Qing Li QIAN; Ping Lai PAN; Yi CHEN; Guo Qing YUAN

    2005-01-01

    A Nd promoted-Rh catalysts supported on polymer-derived carbon beads for vapor-phase methanol carbonylation was developed. Rh-Nd bimetallic catalysts obviously have higher activity than that of supported Rh catalyst under similar reaction condition. The difference between the activity of above two catalyst systems is clearly caused by the intrinsic properties generated by the introduction of Nd.

  13. Development and Long-Term Stability of a Novel Microbial Fuel Cell BOD Sensor with MnO2 Catalyst

    Science.gov (United States)

    Kharkwal, Shailesh; Tan, Yi Chao; Lu, Min; Ng, How Yong

    2017-01-01

    A novel microbial fuel cell (MFC)-based biosensor was designed for continuous monitoring of biochemical oxygen demand (BOD) in real wastewater. To lower the material cost, manganese dioxide (MnO2) was tested as an innovative cathode catalyst for oxygen reduction in a single chamber air-cathode MFC, and two different crystalline structures obtained during synthesis of MnO2 (namely β- and γ-MnO2) were compared. The BOD sensor was studied in a comprehensive way, using both sodium acetate solution and real domestic wastewater (DWW). The optimal performance of the sensor was obtained with a β-MnO2 catalyst, with R2 values of 0.99 and 0.98 using sodium acetate solution and DWW, respectively. The BOD values predicted by the β-MnO2 biosensor for DWW were in agreement with the BOD5 values, determined according to standard methods, with slight variations in the range from 3% to 12%. Finally, the long-term stability of the BOD biosensor was evaluated over 1.5 years. To the best of our knowledge, this is the first report of an MFC BOD sensor using an MnO2 catalyst at the cathode; the feasibility of using a low-cost catalyst in an MFC for online measurement of BOD in real wastewater broadens the scope of applications for such devices. PMID:28134838

  14. Development and Long-Term Stability of a Novel Microbial Fuel Cell BOD Sensor with MnO₂ Catalyst.

    Science.gov (United States)

    Kharkwal, Shailesh; Tan, Yi Chao; Lu, Min; Ng, How Yong

    2017-01-28

    A novel microbial fuel cell (MFC)-based biosensor was designed for continuous monitoring of biochemical oxygen demand (BOD) in real wastewater. To lower the material cost, manganese dioxide (MnO₂) was tested as an innovative cathode catalyst for oxygen reduction in a single chamber air-cathode MFC, and two different crystalline structures obtained during synthesis of MnO₂ (namely β- and γ-MnO₂) were compared. The BOD sensor was studied in a comprehensive way, using both sodium acetate solution and real domestic wastewater (DWW). The optimal performance of the sensor was obtained with a β-MnO₂ catalyst, with R² values of 0.99 and 0.98 using sodium acetate solution and DWW, respectively. The BOD values predicted by the β-MnO₂ biosensor for DWW were in agreement with the BOD₅ values, determined according to standard methods, with slight variations in the range from 3% to 12%. Finally, the long-term stability of the BOD biosensor was evaluated over 1.5 years. To the best of our knowledge, this is the first report of an MFC BOD sensor using an MnO₂ catalyst at the cathode; the feasibility of using a low-cost catalyst in an MFC for online measurement of BOD in real wastewater broadens the scope of applications for such devices.

  15. Nano-magnetite (Fe3O4) as a support for recyclable catalysts in the development of sustainable methodologies.

    Science.gov (United States)

    Gawande, Manoj B; Branco, Paula S; Varma, Rajender S

    2013-04-21

    Surface functionalization of nano-magnetic nanoparticles is a well-designed way to bridge the gap between heterogeneous and homogeneous catalysis. The introduction of magnetic nanoparticles (MNPs) in a variety of solid matrices allows the combination of well-known procedures for catalyst heterogenization with techniques for magnetic separation. Magnetite is a well-known material, also known as ferrite (Fe3O4), and can be used as a versatile support for functionalization of metals, organocatalysts, N-heterocyclic carbenes, and chiral catalysts. It is used as a support for important homogeneous catalytically active metals such as Pd, Pt, Cu, Ni, Co, Ir, etc. to obtain stable and magnetically recyclable heterogeneous catalysts. Homogeneous organocatalysts can be successfully decorated with linkers/ligands on the surface of magnetite or alternatively the organocatalysts can be directly immobilized on the surface of magnetite. The functionalized magnetically retrievable catalysts or nanocatalysts that are increasingly being used in catalysis, green chemistry and pharmaceutically significant reactions are summarized in this review.

  16. Development of a general non-noble metal catalyst for the benign amination of alcohols with amines and ammonia.

    Science.gov (United States)

    Cui, Xinjiang; Dai, Xingchao; Deng, Youquan; Shi, Feng

    2013-03-11

    The N-alkylation of amines or ammonia with alcohols is a valuable route for the synthesis of N-alkyl amines. However, as a potentially clean and economic choice for N-alkyl amine synthesis, non-noble metal catalysts with high activity and good selectivity are rarely reported. Normally, they are severely limited due to low activity and poor generality. Herein, a simple NiCuFeOx catalyst was designed and prepared for the N-alkylation of ammonia or amines with alcohol or primary amines. N-alkyl amines with various structures were successfully synthesized in moderate to excellent yields in the absence of organic ligands and bases. Typically, primary amines could be efficiently transformed into secondary amines and N-heterocyclic compounds, and secondary amines could be N-alkylated to synthesize tertiary amines. Note that primary and secondary amines could be produced through a one-pot reaction of ammonia and alcohols. In addition to excellent catalytic performance, the catalyst itself possesses outstanding superiority, that is, it is air and moisture stable. Moreover, the magnetic property of this catalyst makes it easily separable from the reaction mixture and it could be recovered and reused for several runs without obvious deactivation.

  17. Development and characterisation of novel heterogeneous palm oil mill boiler ash-based catalysts for biodiesel production.

    Science.gov (United States)

    Ho, Wilson Wei Sheng; Ng, Hoon Kiat; Gan, Suyin

    2012-12-01

    Novel heterogeneous catalysts from calcium oxide (CaO)/calcined calcium carbonate (CaCO(3)) loaded onto different palm oil mill boiler ashes were synthesised and used in the transesterification of crude palm oil (CPO) with methanol to yield biodiesel. Catalyst preparation parameters including the type of ash support, the weight percentage of CaO and calcined CaCO(3) loadings, as well as the calcination temperature of CaCO(3) were optimised. The catalyst prepared by loading of 15 wt% calcined CaCO(3) at a fixed temperature of 800°C on fly ash exhibited a maximum oil conversion of 94.48%. Thermogravimetric analysis (TGA) revealed that the CaCO(3) was transformed into CaO at 770°C and interacted well with the ash support, whereas rich CaO, Al(2)O(3) and SiO(2) were identified in the composition using X-ray diffraction (XRD). The fine morphology size (<5 μm) and high surface area (1.719 m(2)/g) of the fly ash-based catalyst rendered it the highest catalytic activity.

  18. Challenges for new electro catalysts development for the ORR in acid medium for PEM fuel cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Savadogo, O. [Ecole Polytechnique, Montreal, PQ (Canada). Laboratory of New Materials for Electrochemistry and Energy

    2010-07-01

    The low kinetic rate at the oxygen reduction reaction (ORR) of platinum (Pt) electrocatalysts in acid mediums is one of the most limiting factors for the industrial mass production of proton exchange membrane fuel cells (PEMFCs). New electrocatalyst materials are currently being investigated by researchers as a replacement for Pt include lignited ruthenium-based chalcogenides; pyrolized iron (Fe) porphyrins; metal carbides; and molybdenum (Mo), iridium (Ir) and cobalt (Co) based catalysts. Co-polypyrrole is also being considered as a non-noble catalyst. This presentation discussed the main parameters that limit the ORR of non-noble catalysts in PEMFC applications. Palladium (Pa) based bi-metallic alloys were investigated. The study showed that Pd-alloy catalysts exhibit excellent activity for the ORR in acidic media. The highest electrocatalytic activity was demonstrated in an alloy composition of 60 per cent Pd. The cost of Pd was compared to the cost of Pt. The intrinsic metal surface properties of Pd-alloys were also discussed, and the onset potential of the ORR was compared for various alloys. 31 refs., 1 tab.

  19. MECHANICAL STRENGTH AND RELIABILITY OF SOLID CATALYSTS

    Institute of Scientific and Technical Information of China (English)

    Yongdan Li; Dongfang Wu; Y.S. Lin

    2004-01-01

    The mechanical strength of solid catalysts is one of the key parameters for reliable and efficient performance of a fixed bed reactor. Some recent developments and their basic mechanics within this context are reviewed. The main concepts discussed are brittle fracture which leads to the mechanical failure of the catalyst pellets, measurement and statistical properties of the catalyst strength data, and mechanical reliability of the catalyst pellets and their packed bed. The scientific basis for the issues on the catalyst mechanical properties calls yet for further elucidation and advancement.

  20. Possibility to predict the development of secondary depression in primary alcoholics during abstinence

    Directory of Open Access Journals (Sweden)

    Mandić-Gajić Gordana

    2005-01-01

    Full Text Available Background/Aim. The relationship between alcoholism and depression is observed in clinical trials. The factors which could predict persistence of secondary depression after alcohol withdrawal are not enough explored on admission. The differences between depressed (DA and non-depressed (NDA alcoholics regarding the degrees of severity of withdrawal, severity of depression and the intensity of cognitive dysfunctions were explored on admission to investigate possibility of prediction of the development of secondary depression in alcoholics. Methods. A group of primary male alcoholics (n=86 was recruited during inpatient treatment. After 4 weeks alcoholics were divided in the DA group (n=43 and NDA (n=43 group according to the score on the Hamilton Depression Rating Scale (HAM-D. Clinical assessment of withdrawal, scoring on the Alcohol Dependency Severity Scale- ASD, and scoring on the Mini Mental Scale-MMSE were performed in all the participants on admission. The differences between the groups were tested by the Student's t-test. Results. The DA group showed the significantly higher severity of depression, higher levels of alcohol withdrawal symptoms and cognitive dysfunctions than the NDA group on admission. Conclusion. The specific group of depressive alcoholics was shown to be characterized by the higher severity of alcoholism and depression on admission, which could predict prolonged, secondary depression. Early detection and concurrent therapy of secondary depression could improve the treatment, and reduce the relapse of alcoholism.

  1. POSSIBILITIES FOR DEVELOPMENT OF BUSINESS CLUSTER NETWORK BETWEEN SMEs FROM VISEGRAD COUNTRIES AND SERBIA

    Directory of Open Access Journals (Sweden)

    Ivan Mihajlović

    2014-10-01

    Full Text Available This issue of Serbian Journal of Management (SJM 9(2 2014, besides containing regular research papers, is containing the papers which resulted from the project “Possibilities for development of business cluster network between SMEs from Visegrad countries and Serbia” and the International May Conference on Strategic Management – IMKSM2014 (http://mksm.sjm06.com . The manuscripts: Entrepreneurs of the Future (Lazani, 2014; The level of process management principles application in SMEs in the selected region of the Czech Republic (Rolinek et al., 2014 and Roles of Socialisation in Strengthening the labour-market positions of young entrants (Marosi, 2014 are the direct result of the Project, which was approved and financially supported by the Visegrad Fund (http://visegradfund.org . On the other hand, the manuscript Workspace as a factor of job satisfaction in the banking and ICT industries in Macedonia (Tomovska, et al., 2014 and Organizational routines in russian companies - review of practicesis (Valieva, 2014 are resulting from the IMKSM2014.

  2. A micro-structured 5kW complete fuel processor for iso-octane as hydrogen supply system for mobile auxiliary power units Part I. Development of autothermal reforming catalyst and reactor

    OpenAIRE

    Kolb, Gunther; Baier, Tobias; Schürer, Jochen; Tiemann, David; Ziogas, Athanassios; Ehwald, Hermann; Alphonse, Pierre

    2008-01-01

    A micro-structured autothermal reformer was developed for a fuel processing/fuel cell system running on iso-octane and designed for an electrical power output of 5kWel. The target application was an automotive auxiliary power unit (APU). The work covered both catalyst and reactor development. In fixed bed screening, nickel and rhodium were identified as the best candidates for autothermal reforming of gasoline. Under higher feed flow rates applied in microchannel testing, a catalyst formul...

  3. Water-Soluble Pd-Imidate Complexes: Broadly Applicable Catalysts for the Synthesis of Chemically Modified Nucleosides via Pd-Catalyzed Cross-Coupling.

    Science.gov (United States)

    Gayakhe, Vijay; Ardhapure, Ajaykumar; Kapdi, Anant R; Sanghvi, Yogesh S; Serrano, Jose Luis; García, Luis; Pérez, Jose; García, Joaquím; Sánchez, Gregorio; Fischer, Christian; Schulzke, Carola

    2016-04-01

    A broadly applicable catalyst system consisting of water-soluble Pd--imidate complexes has been enployed for the Suzuki-Miyaura cross-coupling of four different nucleosides in water under mild conditions. The efficient nature of the catalyst system also allowed its application in developing a microwave-assisted protocol with the purpose of expediting the catalytic reaction. Preliminary mechanistic studies, assisted by catalyst poison tests and stoichiometric tests performed using an electrospray ionization spectrometer, revealed the possible presence of a homotopic catalyst system.

  4. PROGRESS IN CATALYST AND PROCESS DEVELOPMENT FOR LOW SULFUR AND LOW AROMATICS DIESEL PRODUCTION%低硫低芳烃柴油生产技术开发进展

    Institute of Scientific and Technical Information of China (English)

    周勇; 韩崇仁

    2003-01-01

    The article includes three parts: ①The development and performance of FH-DS catalyst for deep and ultra-deep distillate HDS; ②The single stage HDS/HDA hydrotreating process for the production of low sulfur and low aromatics diesels from straight run and coker AGO by using highly active base metal catalyst at moderate pressure; ③A two-stage aromatics saturation system utilizing noble metal catalyst in the second stage developed for production of low sulfur and low aromatics diesel from LCO. FDA catalyst developed by FRIPP has high activity for aromatics saturation together with high tolerance for sulfur and nitrogen in the feed. The process is effective in reducing density and increasing cetane number.

  5. Control in the Rate-Determining Step Provides a Promising Strategy To Develop New Catalysts for CO2 Hydrogenation: A Local Pair Natural Orbital Coupled Cluster Theory Study.

    Science.gov (United States)

    Mondal, Bhaskar; Neese, Frank; Ye, Shengfa

    2015-08-03

    The development of efficient catalysts with base metals for CO2 hydrogenation has always been a major thrust of interest. A series of experimental and theoretical work has revealed that the catalytic cycle typically involves two key steps, namely, base-promoted heterolytic H2 splitting and hydride transfer to CO2, either of which can be the rate-determining step (RDS) of the entire reaction. To explore the determining factor for the nature of RDS, we present herein a comparative mechanistic investigation on CO2 hydrogenation mediated by [M(H)(η(2)-H2)(PP3(Ph))](n+) (M = Fe(II), Ru(II), and Co(III); PP3(Ph) = tris(2-(diphenylphosphino)phenyl)phosphine) type complexes. In order to construct reliable free energy profiles, we used highly correlated wave function based ab initio methods of the coupled cluster type alongside the standard density functional theory. Our calculations demonstrate that the hydricity of the metal-hydride intermediate generated by H2 splitting dictates the nature of the RDS for the Fe(II) and Co(III) systems, while the RDS for the Ru(II) catalyst appears to be ambiguous. CO2 hydrogenation catalyzed by the Fe(II) complex that possesses moderate hydricity traverses an H2-splitting RDS, whereas the RDS for the high-hydricity Co(III) species is found to be the hydride transfer. Thus, our findings suggest that hydricity can be used as a practical guide in future catalyst design. Enhancing the electron-accepting ability of low-hydricity catalysts is likely to improve their catalytic performance, while increasing the electron-donating ability of high-hydricity complexes may speed up CO2 conversion. Moreover, we also established the active roles of base NEt3 in directing the heterolytic H2 splitting and assisting product release through the formation of an acid-base complex.

  6. Synthesis of Organic Compounds over Selected Types of Catalysts

    Directory of Open Access Journals (Sweden)

    Omar Mohamed Saad Ismail

    2011-05-01

    Full Text Available This study provides an overview for the utilization of different catalytic material in the synthesis of organic compounds for important reactions such as heck reaction, aldol reaction, Diels- Alder and other reactions. Comparisons between multiple catalysts for the same reaction and justifications for developing new catalyzed materials are discussed. The following topics are introduced in this work; (1 solid base catalysts, (2 clay catalysts, (3 palladium catalysts, and (4 catalysts to produce organic compound from CO2. The features of these catalysts a long with the conjugated reactions and their selectivity are explained in details, also, some alternatives for toxic or polluting catalysts used in industry are suggested.

  7. FCC Catalysts to Meet Demand of New Era

    Institute of Scientific and Technical Information of China (English)

    Yu Daping

    2008-01-01

    The CGP series FCC catalysts for manufacture of clean gasoline and propylene and the catalyst RSC-2006 for processing inferior residuum with high yield of light distillates are novel catalysts jointly developed by Qilu Catalyst Branch Company of SINOPEC Corp. and the Research Institute of Petroleum Processing (RIPP). The results of commercial application of these catalysts have revealed that they can satisfactorily meet the requirements for environmental protection, good economic benefits and capability for processing inferior FCC feed under new circumstances.

  8. Development of high-performance cathode catalyst of polypyrrole modified carbon supported CoOOH for direct borohydride fuel cell

    Science.gov (United States)

    He, Yan; Zhu, Cai; Chen, Kaijian; Wang, Juan; Qin, Haiying; Liu, Jiabin; Yan, Shuai; Yang, Ke; Li, Aiguo

    2017-01-01

    Polypyrrole modified carbon supported CoOOH electrocatalyst (CoOOH-PPy-C) is prepared by impregnation-chemical method, and the catalytic properties for the oxygen reduction reaction (ORR) in alkaline media are investigated. The X-ray diffraction and transmission electron microscopy results confirm the presence of the expected CoOOH. The electrochemical tests show that the CoOOH-PPy-C catalyst exhibits good electrocatalytic activity towards ORR. The direct borohydride fuel cell using CoOOH-PPy-C as the cathode catalyst demonstrates a good stability performance. There is only 4% decrease of the cell voltage after 80-h operation. The ORR occurs an average 4-electron transfer pathway on the CoOOH-PPy-C catalyst. The good catalytic activity towards ORR benefits from the Cosbnd N bond, which is identified by X-ray photoelectron spectroscopy test. X-ray absorption fine structure experiments further show that two nearest O atoms are substituted by two N atoms bonding to Co ion at a distance of 1.64 Å. The CoOOH-PPy-C exhibits better electrochemical properties than the Co(OH)2 counterpart even though the valence state of Co ion is +3 in CoOOH-PPy-C. Those results indicate that the bonding of Co ion with N atoms should be a key issue regardless the valence of Co ion.

  9. Novel Attrition-Resistant Fischer Tropsch Catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Weast, Logan, E.; Staats, William, R.

    2009-05-01

    There is a strong national interest in the Fischer-Tropsch synthesis process because it offers the possibility of making liquid hydrocarbon fuels from reformed natural gas or coal and biomass gasification products. This project explored a new approach that had been developed to produce active, attrition-resistant Fischer-Tropsch catalysts that are based on glass-ceramic materials and technology. This novel approach represented a promising solution to the problem of reducing or eliminating catalyst attrition and maximizing catalytic activity, thus reducing costs. The technical objective of the Phase I work was to demonstrate that glass-ceramic based catalytic materials for Fischer-Tropsch synthesis have resistance to catalytic deactivation and reduction of particle size superior to traditional supported Fischer-Tropsch catalyst materials. Additionally, these novel glass-ceramic-based materials were expected to exhibit catalytic activity similar to the traditional materials. If successfully developed, the attrition-resistant Fischer-Tropsch catalyst materials would be expected to result in significant technical, economic, and social benefits for both producers and public consumers of Fischer-Tropsch products such as liquid fuels from coal or biomass gasification. This program demonstrated the anticipated high attrition resistance of the glass-ceramic materials. However, the observed catalytic activity of the materials was not sufficient to justify further development at this time. Additional testing documented that a lack of pore volume in the glass-ceramic materials limited the amount of surface area available for catalysis and consequently limited catalytic activity. However, previous work on glass-ceramic catalysts to promote other reactions demonstrated that commercial levels of activity can be achieved, at least for those reactions. Therefore, we recommend that glass-ceramic materials be considered again as potential Fischer-Tropsch catalysts if it can be

  10. A sustainable development in the energy sector is quite possible; En baerekraftig utvikling i energisektoren er fullt mulig

    Energy Technology Data Exchange (ETDEWEB)

    Lind, Oddvar

    1999-07-01

    The article deals with the possibilities of obtaining a sustainable development in the global energy sector during the first part of the next century. It should be possible to reduce the poverty problems in the energy sector by half by the year 2020 and lower the discharge of climatic gases considerably. Developments directions are pointed out and major challenges and pollution control measures are outlined. The World Energy Council global energy information system is mentioned.

  11. SELECTIVE REDUCTION OF NOX IN OXYGEN RICH ENVIRONMENTS WITH PLASMA-ASSISTED CATALYSIS: CATALYST DEVELOPMENT AND MECHANISTIC STUDIES

    Energy Technology Data Exchange (ETDEWEB)

    Peden, C; Barlow, S; Hoard, J; Kwak, J; *Balmer-Millar, M; *Panov, A; Schmieg, S; Szanyi, J; Tonkyn, R

    2003-08-24

    The control of NOx (NO and NO2) emissions from so-called ''lean-burn'' vehicle engines remains a challenge. In recent years, there have been a number of reports that show that a plasma device combined with a catalyst can reduce as high as 90% or more of NOx in simulated diesel and other ''lean-burn'' exhaust. In the case of propylene containing simulated diesel exhaust, the beneficial role of a plasma treatment is now thought to be due to oxidation of NO to NO2, and the formation of partially oxidized hydrocarbons that are more active for the catalytic reduction of NO2 than propylene. Thus, the overall system can be most usefully described as hydrocarbon selective catalytic reduction (SCR) enhanced by 'reforming' the exhaust with a non-thermal plasma (NTP) device. For plasma-enhanced catalysis, both zeolite- and alumina-based materials have shown high activity, albeit in somewhat different temperature ranges, when preceded by an NTP reactor. This paper will briefly describe our research efforts aimed at optimizing the catalyst materials for NTP-catalysis devices based, in part, on our continuing studies of the NTP- and catalytic-reaction mechanisms. Various alkali- and alkaline earth-cation-exchanged Y zeolites have been prepared, their material properties characterized, and they have been tested as catalytic materials for NOx reduction in laboratory NTP-catalysis reactors. Interestingly, NO2 formed in the plasma and not subsequently removed over these catalysts, will back-convert to NO, albeit to varying extents depending upon the nature of the cation. Besides this comparative reactivity, we will also discuss selected synthesis strategies for enhancing the performance of these zeolite-based catalyst materials. A particularly important result from our mechanistic studies is the observation that aldehydes, formed during the plasma treatment of simulated diesel exhaust, are the important species for the reduction of

  12. Liquid Phase Hydrogenation of Benzalacetophenone:Effect of Solvent,Catalyst Support,Catalytic Metal and Reaction Conditions%Liquid Phase Hydrogenation of Benzalacetophenone: Effect of Solvent, Catalyst Support, Catalytic Metal and Reaction Conditions

    Institute of Scientific and Technical Information of China (English)

    Achim STOLLE; Christine SCHMOGER; Bernd ONDRUSCHKA; Werner BONRATH; Thomas F. KELLER; Klaus D. JANDT

    2011-01-01

    Innovative catalysts based on a “porous glass” support material were developed and investigated for the reduction of benzalacetophenone.The easy preparation conditions and possibility to use different metals (e.g.Pd,Pt,Rh) for impregnation gave a broad variety of these catalysts.Hydrogenation experiments with these supported catalysts were carried out under different hydrogen pressures and temperatures.Porous glass catalysts with Pd as the active component gave chemoselective hydrogenation of benzalacetophenone,while Pt- and Rh-catalysts tended to further reduce the carbonyl group,especially at elevated hydrogen pressures and temperatures.Kinetic analysis of the reactions revealed these had zero order kinetics,which was independent of the type of porous glass support and solvent used.

  13. A New Concept for Advanced Heterogeneous Metal Catalysts

    Institute of Scientific and Technical Information of China (English)

    Xu Bo-Qing

    2004-01-01

    Oxide-supported metal catalysts, having always nano-sized structures in which the metal catalysts are prepared as highly dispersed nano-crystals (typically 1-20 nm) on support oxide particles that are often one to several orders of magnitude larger than the metal nano-particles, are an important class of heterogeneous metal catalysts that finds many applications in chemical/petrochemical industries, in environmental protection, in chemical sensors and in the manufacture of fine and special chemicals. It is believed that catalysis by supported metals is the oldest application of nanotechnology. The literature has been rich in nano-size effect of metal nanoparticles in the metal/oxide catalysts. However, it is until recently that the development of size-controlled synthesis of oxide nanoparticles has made it possible to study the nano-size effect of oxide-support particles. When the particle sizes of an oxide support are reduced to become comparable to the sizes of the active metal nanoparticles, the oxide could deviate dramatically from its function as a conventional support. Such metal/oxide catalysts consisting of comparably sized metal and oxide nanocrystals are better called metal/oxide nanocomposite catalysts or catalytic nanoarchitectures.In this presentation, several attempts with reducing the particle size of oxide supports (ZrO2, TiO2,MgO, Al2O3) to approach the metal/oxide nanocomposite concept will be discussed to emphasize the importance of the support size effect. Examples will be given on characteristics of nanocomposite Ni/oxide catalysts for the reforming of natural gas with CO2 and/or steam, and on Au/oxide catalysts for CO oxidation and hydrogenation of unsaturated organic compounds. It will be emphasized that systematic investigations into the size effects of both the metal and oxide nanoparticles approaching the metal/oxide nanocomposite concept can lead to advanced heterogeneous metal catalysts.Moreover, intensive practice of the nanocomposite

  14. Mechanochemistry, catalysis, and catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Butyagin, P.Yu.

    1987-07-01

    The physical basis of mechanochemistry and the reasons for the initiation and acceleration of chemical reactions upon the mechanical treatment of solids have been considered. The phenomenon of mechanical catalysis has been described in the example case of the oxidation of CO on oxide surfaces, and the nature of the active sites and the laws governing the mechanically activated chemisorption of gases on cleavage and friction surfaces of solids have been examined. The possibilities of the use of the methods of mechanochemistry in processes used to prepare catalysts have been analyzed in examples of decomposition reactions of inorganic compounds and solid-phase synthesis.

  15. Nitrogen-doped Carbon Derived from ZIF-8 as a High-performance Metal-free Catalyst for Acetylene Hydrochlorination

    Science.gov (United States)

    Chao, Songlin; Zou, Fang; Wan, Fanfan; Dong, Xiaobin; Wang, Yanlin; Wang, Yuxuan; Guan, Qingxin; Wang, Guichang; Li, Wei

    2017-01-01

    Acetylene hydrochlorination is a major industrial technology for manufacturing vinyl chloride monomer in regions with abundant coal resources; however, it is plagued by the use of mercury(II) chloride catalyst. The development of a nonmercury catalyst has been extensively explored. Herein, we report a N-doped carbon catalyst derived from ZIF-8 with both high activity and quite good stability. The acetylene conversion reached 92% and decreased slightly during a 200 h test at 220 °C and atmospheric pressure. Experimental studies and theoretical calculations indicate that C atoms adjacent to the pyridinic N are the active sites, and coke deposition covering pyridinic N is the main reason for catalyst deactivation. The performance of those N-doped carbons makes it possible for practical applications with further effort. Furthermore, the result also provides guidance for designing metal-free catalysts for similar reactions.

  16. Possible Effects of Electronic Social Media on Gifted and Talented Children's Intelligence and Emotional Development

    Science.gov (United States)

    Freeman, Joan

    2016-01-01

    In just a few decades, electronic networks have expanded beyond all expectations. Instant messaging via smart phones and computers of all sorts whizz round the world. Researchers and policy makers are strongly divided in their findings and conclusions as to the effects of possible persuasive changes on the minds and lives of children, particularly…

  17. Carbon-based catalysts:Opening new scenario to develop next-generation nano-engineered catalytic materials

    Institute of Scientific and Technical Information of China (English)

    Claudio Ampelli; Siglinda Perathoner; Gabriele Centi

    2014-01-01

    This essay analyses some of the recent development in nanocarbons (carbon materials having a defined and controlled nano-scale dimension and functional properties which strongly depend on their nano-scale features and architecture), with reference to their use as advanced catalytic materials. It is remarked how their features open new possibilities for catalysis and that they represent a new class of catalytic materials. Although carbon is used from long time in catalysis as support and electrocatalytic applications, nanocarbons offer unconventional ways for their utilization and to address some of the new challenges deriving from moving to a more sustainable future. This essay comments how nanocarbons are a key element to develop next-generation catalytic materials, but remarking that this goal requires overcoming some of the actual limits in current research. Some aspects are discussed to give a glimpse on new directions and needs for R&D to progress in this direction.

  18. The development of guided regeneration: making the impossible possible and the unpredictable predictable.

    Science.gov (United States)

    Scantlebury, Todd; Ambruster, Jeanne

    2012-09-01

    Using their perspectives as early participants in guided regeneration development, the authors review the history of guided regeneration: from the precursive studies leading to the development of guided tissue regeneration for periodontium, through the development of guided bone regeneration for implants, to the long-term performance studies validating effectiveness. Landmark publications, original patents, and reviews are used to trace the therapy's development. By examining key studies and the scientists and clinicians who conducted them, the authors present clinical and biomaterials lessons learned and discuss developments that could shape the next guided regeneration developments.

  19. Catalyst deactivation. Is it predictable? What to do?

    Energy Technology Data Exchange (ETDEWEB)

    Moulijn, J.A.; Van Diepen, A.E.; Kapteijn, F. [Department of Chemical Process Technology, Section of Industrial Catalysis, Faculty of Applied Sciences, Delft University of Technology, Julianalaan 136, 2628 BL Delft (Netherlands)

    2001-04-30

    Catalyst deactivation is usually inevitable, although the rate at which it occurs varies greatly. This article discusses the causes of deactivation and the influence on reaction rate. Methods for minimising catalyst deactivation, by tailoring catalyst properties and/or process operations, are presented, as well as reactor configurations suitable for the regeneration of deactivated catalysts. Alkane dehydrogenation is used as an example to demonstrate the variety of engineering solutions possible.

  20. Developing business advantages from the technological possibilities of enterprise information systems

    Directory of Open Access Journals (Sweden)

    Luay Anaya

    2014-01-01

    Full Text Available Organizations are increasingly implementing Enterprise Information Systems (EIS, and Enterprise Resource Planning (ERP systems in particular. Despite the notable studies on the advantages of an EIS, many organizations are not satisfied with the benefits or advantages gained. At the same time, it is assumed that such systems with increasing innovations and technological enhancements would generate abundant business advantages, if organizations exploited these opportunities. The investigation in this work drew on the sociomateriality perspective, using imbrication notion, and focused on a telecomm case study to examine how organizations can exploit the technological possibilities of an EIS to create business benefits. The study findings suggest that business benefits can be achieved when the EIS as a technical system is interwoven with the organizational work in which both dynamically change in practice (not from the technical features of the system, when the system provides interesting and beneficial technological possibilities that attract organizations, and when the firm has the organizational capabilities to translate these possibilities into real business benefits.

  1. Electrochemical catalyst recovery method

    Science.gov (United States)

    Silva, Laura J.; Bray, Lane A.

    1995-01-01

    A method of recovering catalyst material from latent catalyst material solids includes: a) combining latent catalyst material solids with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form a mixture; b) electrochemically oxidizing the redox material within the mixture into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the latent catalyst material; c) reacting the oxidant with the latent catalyst material to oxidize the latent catalyst material into at least one oxidized catalyst species which is soluble within the mixture and to reduce the oxidant back into dissolved redox material; and d) recovering catalyst material from the oxidized catalyst species of the mixture. The invention is expected to be particularly useful in recovering spent catalyst material from petroleum hydroprocessing reaction waste products having adhered sulfides, carbon, hydrocarbons, and undesired metals, and as well as in other industrial applications.

  2. On the Role of Glutamate in Presynaptic Development: Possible Contributions of Presynaptic NMDA Receptors

    Directory of Open Access Journals (Sweden)

    Karlie N. Fedder

    2015-12-01

    Full Text Available Proper formation and maturation of synapses during development is a crucial step in building the functional neural circuits that underlie perception and behavior. It is well established that experience modifies circuit development. Therefore, understanding how synapse formation is controlled by synaptic activity is a key question in neuroscience. In this review, we focus on the regulation of excitatory presynaptic terminal development by glutamate, the predominant excitatory neurotransmitter in the brain. We discuss the evidence that NMDA receptor activation mediates these effects of glutamate and present the hypothesis that local activation of presynaptic NMDA receptors (preNMDARs contributes to glutamate-dependent control of presynaptic development. Abnormal glutamate signaling and aberrant synapse development are both thought to contribute to the pathogenesis of a variety of neurodevelopmental disorders, including autism spectrum disorders, intellectual disability, epilepsy, anxiety, depression, and schizophrenia. Therefore, understanding how glutamate signaling and synapse development are linked is important for understanding the etiology of these diseases.

  3. 氨合成钌基催化剂的研究进展%Development in ruthenium based catalysts for ammonia synthesis

    Institute of Scientific and Technical Information of China (English)

    郭淑静; 高俊文

    2015-01-01

    Recently,ruthenium based catalysts for ammonia synthesis have been attracting interest increasingly due to their higher activity,higher stability and mild reaction conditions. The advance in development of Ru based catalysts for ammonia synthesis at home and abroad,especially the influence of the catalyst supports,promoters and precursors on the performance of ammonia synthetic catalysts were introduced in this paper. The carbon supports,carbon covered oxide and their complex with high graphitic degree and good electrical conductivity were good choice for ammonia synthesis supports. Alkali metals and alkaline-earth metals were good promoters for ammonia synthesis,and the promoting effects of alkaline-earth metals were better than those of alkali metals. Rear earth metals Sm could inhibit carbon methanation. Compared with RuCl3 ,Ru3( CO )12 was the ideal precursor for ammonia synthesis. A electride C12 A7:e- with high surface area,which worked as an excellent electron donor and reversible hydrogen-storage material,was used as support for Ru based catalyst for ammonia synthesis,and the cata-lytic activity for ammonia synthesis was greatly enhanced. The development of non-noble metal ammonia synthesis catalysts under mild conditions in the future is also proposed.%近年来,钌基氨合成催化剂因其高活性、高稳定性和反应条件温和成为研究热点。综述国内外氨合成钌基催化剂的研究进展,重点介绍钌基催化剂载体、助剂和前驱体对氨合成反应性能的影响。石墨化程度高、导电性能良好的碳载体或氧化物与碳的复合载体是氨合成反应的良好载体;碱金属和碱土金属类助剂通过改变活性金属表面静电场,起到电子助剂的作用,并且碱土金属对反应的促进作用优于碱金属,稀土金属Sm能够抑制碳载体的甲烷化反应;与RuCl3相比,Ru3( CO)12是氨合成反应的理想前驱体。简介以电子化合物为载体的钌基氨合

  4. Attrition Resistant Iron-Based Catalysts For F-T SBCRs

    Energy Technology Data Exchange (ETDEWEB)

    Adeyinka A. Adeyiga

    2006-01-31

    The Fischer-Tropsch (F-T) reaction provides a way of converting coal-derived synthesis gas (CO+ H{sub 2}) to liquid fuels. Since the reaction is highly exothermic, one of the major problems in control of the reaction is heat removal. Recent work has shown that the use of slurry bubble column reactors (SBCRs) can largely solve this problem. The use of iron-(FE) based catalysts is attractive not only due to their low cost and ready availability, but also due to their high water-gas shift activity which makes it possible to use these catalysts with low H{sub 2}/CO ratios. However, a serious problem with the use of Fe catalysts in a SBCR is their tendency to undergo attrition. This can cause fouling/plugging of downstream filters and equipment; makes the separation of catalyst from the oil/wax product very difficult, if not impossible; and results in a steady loss of catalyst from the reactor. Under a previous Department of Energy (DOE)/University Research Grant (UCR) grant, Hampton University reported, for the first time, the development of demonstrably attrition-resistant Fe F-T synthesis catalysts having good activity, selectivity, and attrition resistance. These catalysts were prepared by spray drying Fe catalysts with potassium (K), copper (Cu), and silica (SiO{sub 2}) as promoters. SiO{sub 2} was also used as a binder for spray drying. These catalysts were tested for activity and selectivity in a laboratory-scale fixed-bed reactor. Fundamental understanding of attrition is being addressed by incorporating suitable binders into the catalyst recipe. This has resulted in the preparation of a spray dried HPR-43 catalyst having average particle size (aps) of 70 {micro}m with high attrition resistance. This HPR-43 attrition resistant, active and selective catalyst gave 95% CO conversion through 125 hours of testing in a fixed-bed at 270 C, 1.48 MPa, H{sub 2}/CO=0.67 and 2.0 NL/g-cat/h with C{sub 5+} selectivity of >78% and methane selectivity of less than 5% at an

  5. Molecular catalysts structure and functional design

    CERN Document Server

    Gade, Lutz H

    2014-01-01

    Highlighting the key aspects and latest advances in the rapidly developing field of molecular catalysis, this book covers new strategies to investigate reaction mechanisms, the enhancement of the catalysts' selectivity and efficiency, as well as the rational design of well-defined molecular catalysts. The interdisciplinary author team with an excellent reputation within the community discusses experimental and theoretical studies, along with examples of improved catalysts, and their application in organic synthesis, biocatalysis, and supported organometallic catalysis. As a result, readers wil

  6. In-situ reduction of a methanol synthesis catalyst in a three-phase slurry reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sawant, A.; Ko, M.K.; Parameswaran, V.; Lee, S.; Kulik, C.J.

    1987-01-01

    A new method for the reduction of metal oxide catalysts (CuO, ZnO, Al/sub 2/O/sub 3/) has been developed for liquid phase methanol synthesis. The reducing agent is a 5% hydrogen in nitrogen mixture and the operation is carried out at 446.09 KPa. This method makes it possible to reduce finely crushed catalyst (-100 + 120 mesh) in a three phase slurry reactor. This method offers several advantages over methods in which the catalyst is reduced in a gas-solid contact mode and then slurried for use. The catalyst has been shown to be very effectively reduced and reaches its full production capacity after reduction.

  7. Possibility of the development of a Serbian protection system against chemical accidents

    Directory of Open Access Journals (Sweden)

    Dejan R. Inđić

    2012-10-01

    Full Text Available The paper presents a draft of a system model for responding in case of chemical accidents in accordance with the current legislation regarding the environment protection, the structure and elements of the existing response system in case of chemical accidents, other works dealing with the issue as well as the prospects planned by those responsible for the environmental protection. The paper discuss the possibilities of different institutions and agencies of the Republic of Serbia to engage in specialized methods of cooperation and protection against chemical hazards in accordance with Article X of the Convention on the Prohibition of Chemical Weapons.

  8. Effect of teratogenic exposure on the developing brain: research strategies and possible mechanisms.

    Science.gov (United States)

    Grimm, V E

    1987-01-01

    Some of the problems associated with human behavioral teratology are reviewed and research strategies necessary for the elucidation of the possible prenatal bases for the later occurrence of Learning Disabilities (LD) are suggested. An animal model for LD was created by exposure of female rats during pregnancy or during lactation to diazepam, monosodium glutamate, caffeine, or maternal stress. The gestation period most sensitive to these prenatal insults was established, and some of the neurochemical and histological correlates of the resulting discrimination learning deficits were investigated.

  9. Developing Talented Soccer Players: An Analysis of Socio-Spatial Factors as Possible Key Constraints

    Directory of Open Access Journals (Sweden)

    Serra-Olivares Jaime

    2016-12-01

    Full Text Available Most studies on the identification and development of soccer talent have been one-dimensional in nature. Although some multi-dimensional analyses have been conducted, few research studies have assessed in any depth the socio-spatial factors influencing talent development. The aim of this particular study was to analyse variations in the international representation of clubs (n = 821 and countries (n = 59 in the development of players who took part in the 2014 FIFA Soccer World Cup. Clubs and countries were ranked and divided into quartiles according to the number of players developed between the ages of 15 and 21 (clubs and countries that developed players for at least three years between these ages and the number of official league matches played by these players up to the age of 23. Significant variations were observed between clubs in terms of the number of developed players who took part in the World Cup and the number of official league matches played by these players up to the age of 23 (p < .05, and also between countries (p < .05. The findings reveal the need to carry out more in-depth studies into the type of training and competition engaged in by elite players in the period of development between the ages of 15 and 21. It may be the case that these factors are potentially decisive socio-spatial constraints in the development of soccer talent.

  10. Bridge Building and Other Possible Metaphors for Patching over Discrepancies between Typical and Atypical Development

    Science.gov (United States)

    Chandler, Michael

    2016-01-01

    The next several pages are intended as a "Commentary" on the six target articles bundled together as a Special Issue of the "Journal of Cognition and Development"--literature reviews and research reports all intended to "build bridges" between the study of cognitive development in typical and atypical populations.

  11. Young Adulthood to Old Age: Looking at Intergenerational Possibilities from a Human Development Perspective.

    Science.gov (United States)

    ReVille, Shari

    1989-01-01

    The potential interface between human development theories and intergenerational programing is explored. Erik Erikson's division of adult development into young, middle, and later adulthood, and Butler and Lewis'"characteristics of older people," are considered. Older people can offer help and encouragement to youth while themselves…

  12. NEW NEPHRON DEVELOPMENT IN FISH FROM POLLUTED WATERS: A POSSIBLE BIOMARKER

    Science.gov (United States)

    Recent evidence has shown that fish have the ability to develop new nephrons following renal injury. This study evaluated the usefulness of quantifying developing nephrons in mature fish as an ecotoxicological assessment tool. Histological sections of kidney were prepared from At...

  13. Development of a reactor with carbon catalysts for modular-scale, low-cost electrochemical generation of H 2 O 2

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zhihua; Chen, Shucheng; Siahrostami, Samira; Chakthranont, Pongkarn; Hahn, Christopher; Nordlund, Dennis; Dimosthenis, Sokaras; Nørskov, Jens K.; Bao, Zhenan; Jaramillo, Thomas F.

    2017-03-01

    The development of small-scale, decentralized reactors for H2O2 production that can couple to renewable energy sources would be of great benefit, particularly for water purification in the developing world. Herein, we describe our efforts to develop electrochemical reactors for H2O2 generation with high Faradaic efficiencies of >90%, requiring cell voltages of only ~1.6 V. The reactor employs a carbon-based catalyst that demonstrates excellent performance for H2O2 production under alkaline conditions, as demonstrated by fundamental studies involving rotating-ring disk electrode methods. The low-cost, membrane-free reactor design represents a step towards a continuous, modular-scale, de-centralized production of H2O2.

  14. Administrative circular No. 2 (Rev. 5) – Recruitment, appointment and possible developments regarding the contractual position of staff members

    CERN Multimedia

    HR Department

    2011-01-01

    Administrative Circular No. 2 (Rev. 5) entitled "Recruitment, appointment and possible developments regarding the contractual position of staff members", approved by the Director-General following discussion in the Standing Concertation Committee meeting on 1 September 2011, is available on the intranet site of the Human Resources Department: https://cern.ch/hr-docs/admincirc/admincirc.asp It cancels and replaces Administrative Circular No. 2 (Rev. 4) entitled "Recruitment, appointment and possible developments regarding the contractual position of staff members" of September 2009. Department Head Office

  15. Museums, Learning Centers and Education for Sustainable Development: Practices and Possibilities in the Oslo Area

    OpenAIRE

    Ott, Annelie

    2014-01-01

    This study sets out to examine the potential of four Oslo museums / learning centers for Education for Sustainable Development (ESD). ESD has gained ground in the course of UNESCO`s Decade for Education for Sustainable Development and includes cognitive, affective and practical sustainability learning. It aims to raise aware, committed and participating citizens. UNESCO outlines ESD as a broad concept which comprises different branches of education, targets people of all ages and includes mat...

  16. Effects of New Fossil Fuel Developments on the Possibilities of Meeting 2C Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Meindertsma, W.; Blok, K.

    2012-12-15

    Recent years have seen an increasing activity in developing new fossil fuel production capacity. This includes unconventional fossil fuels, such as tar sands and shale gas, fossil fuels from remote locations, and fossil fuels with a very large increase in production in the near future. In this report, the impact of such developments on our ability to mitigate climate change is investigated. Our inventory shows that the new fossil fuel developments currently underway consist of 29,400 billion cubic meters of natural gas, 260,000 million barrels of oil and 49,600 million tonnes of coal. The development of these new fossil fuels would result in emissions of 300 billion tonnes of CO2 -equivalent (CO2e) from 2012 until 2050. Until 2050, a 'carbon budget' of 1550 billion tonnes CO2e is still available if we want to of keep global warming below 2C with a 50% probability. For a 75% probability to stay below 2C this budget is only 1050 billion tonnes CO2e. So, the new fossil fuel developments identified in this report consume 20-33% of the remaining carbon budget until 2050. In a scenario where the new fossil fuels are developed, we need to embark on a rapid emission reductions pathway at the latest in 2019 in order to meet the 50% probability carbon budget. Avoiding the development of new fossil fuels will give us until 2025 to start further rapid emission reductions. These calculations are based on the assumption that the maximum emission reduction rate is 4% per year and that the maximum change in emission trend is 0.5 percentage point per year. The starting year for rapid emission reductions depends on the choice of these parameters. A sensitivity analysis shows that, in all cases, refraining from new fossil fuel development allows for a delay of 5 to 8 years before we should embark on a rapid emission reduction pathway. The high investments required for developing new fossil fuels lead to a lock in effect; once developed, these fossil fuels need to be

  17. Organic synthesis with olefin metathesis catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Grubbs, R.H. [California Institute of Technology, Pasadena, CA (United States)

    1995-12-31

    Over the past nine years, early transition metal catalysts for the ring opening metathesis polymerization of cyclic olefins have been developed. These catalysts are simple organometallic complexes containing metal carbon multiple bonds that in most cases polymerize olefins by a living process. These catalysts have been used to prepare a family of near monodispersed and structurally homogeneous polymers. A series of group VII ROMP catalysts that allow a wide range of functionality to be incorporated into the polymer side chains have been prepared. The most important member of this family of complexes are the bisphosphinedihalo-ruthenium carbene complexes. These polymerization catalysts can also be used in the synthesis of fine chemicals by ring closing (RCM) and vinyl coupling reactions. The availability of the group VII catalysts allow metathesis to be carried out on highly functionalized substrates such as polypeptides and in unusual environments such as in aqueous emulsions.

  18. European Renal Best Practice (ERBP) Guideline development methodology: towards the best possible guidelines.

    Science.gov (United States)

    Nagler, Evi V; Webster, Angela C; Bolignano, Davide; Haller, Maria C; Nistor, Ionut; van der Veer, Sabine N; Fouque, Denis; Van Biesen, Wim

    2014-04-01

    The prime mission of European Renal Best Practice (ERBP) is to improve the outcome of patients with kidney disease in a sustainable way through enhancing the availability of the knowledge on the management of these patients in a format that stimulates its use in clinical practice in Europe. A key activity is to produce clinical practice guidelines to help clinicians make the healthcare decisions they face. To further improve the quality and validity of its clinical practice guidelines, ERBP has revised its guideline development process. The present document outlines the principles of ERBP's 10-step approach. Important features include standard procedures for selecting topics, for assembling the guideline development group, for choosing and formulating questions, for finding, appraising and summarizing the evidence, for generating recommendations, for preparing reports and organizing peer review. ERBP has adopted the Grading of Recommendations Assessment, Development and Evaluation system for rating the quality of the evidence and strength of recommendations and has addressed implementation in the development process by integrating the GuideLine Implementability Appraisal tool. Ultimately, it is anticipated that these changes will not only further improve the quality of the guideline development process, but also enhance the quality of care and improve outcomes of patients with kidney disease across Europe.

  19. Science Letters:Development of supported boron-doping TiO2 catalysts by chemical vapor deposition

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In this study, supported nonmetal (boron) doping TiO2 coating photocatalysts were prepared by chemical vapor deposition (CVD) to enhance the activity under visible light irradiation and avoid the recovering of TiO2. Boron atoms were successfully doped into the lattice of TiO2 through CVD, as evidenced from XPS analysis. B-doped TiO2 coating catalysts showed drastic and strong absorption in the visible light range with a red shift in the band gap transition. This novel B-TiO2 coating photocatalyst showed higher photocatalytic activity in methyl orange degradation under visible light irradiation than that of the pure TiO2 photocatalyst.

  20. Interaction between Nafion ionomer and noble metal catalyst for PEMFCs

    DEFF Research Database (Denmark)

    Andersen, Shuang Ma

    The implement of polymer impregnation in electrode structure (catalyst layer) decreasing the noble metal catalyst loading by a factor of ten , , is one of the essential mile stones in the evolution of Proton Exchange Membrane Fuel Cells’ development among the application of catalyst support...... and electrode deposition etc. In fuel cell reactions, both electrons and protons are involved. Impregnation of Nafion ionomer in catalyst layer effectively increases the proton-electron contact, enlarge the reaction zone, extend the reaction from the surface to the entire electrode. Therefore, the entire...... catalyst layer conducts both electrons and protons so that catalyst utilization in the layer is improved dramatically. The catalyst layer will in turn generate and sustain a higher current density. One of the generally adapted methods to impregnate Nafion into the catalyst layer is to mix the catalysts...

  1. Using possibility of QFD method for development of the "ready-to-go" package

    Directory of Open Access Journals (Sweden)

    Jelena Dragoljub Krstic

    2014-07-01

    Full Text Available Although quality function deployment (QFD is the mostly used in the development of new products, the methodology is equally varied and applied as a packaging design/development tool. Due to the fact that the demands of the market, i.e. users are constantly changing, the designers of all products, as well as the designers of packaging for food products, must implement the introduced requirements on the newly design of its products. The goal of this paper was to explain the QFD method with the aim to understand the mode of its operation and implementation, with an explanation of its potential for practical application in the packaging design process, as well as to highlight all the advantages and disadvantages of this method. The goal of the implementation of QFD method during the development of the packaging, as one of the types of products, is to find exactly the features and functions of the customer, i.e. what the user expects from the packaging, i.e. by this method, customer's voice transforms into new products that really meet their needs. It can be concluded that the application of QFD methods can reduce the length of the product development cycle, in this case the packaging, while simultaneously improving the quality and marketing of products in the market.

  2. BARRETTS-ESOPHAGUS AND CARCINOMA - RECENT INSIGHTS INTO ITS DEVELOPMENT AND POSSIBLE PREVENTION

    NARCIS (Netherlands)

    PETERS, FTM; KLEIBEUKER, JH

    1993-01-01

    Barrett's oesophagus or columnar epithelium-lined oesophagus is a condition due to chronic gastrooesophageal reflux. In addition to acid-peptic reflux, reflux of duodenal contents may have a role in its aetiology. The clinical importance of Barrett's oesophagus is the increased risk for development

  3. Assessing Training Priorities in Developing Countries: Current Practice and Possible Alternatives.

    Science.gov (United States)

    Psacharopoulos, George

    1984-01-01

    This essay deals with a series of methodological issues involved in assessing training priorities in developing countries. It is argued that the present methods of arriving at these priorities leave much to be desired, and a number of suggestions are made that might lead to more informed policy decisions on education and training. (CT)

  4. Posibilidades y limites de un fomento cognitivo temprano (Possibilities and Limits of Early Cognitive Development).

    Science.gov (United States)

    Schmalohr, Emil

    This article discusses preschool education and the research conducted in that field on various relevant topics in an effort to establish recommendations and programs. Cognitive development is the main issue and is seen as a product of maturation as well as of a broad base of experience which results from interaction between the mind and the…

  5. Possibilities and pitfalls for modern biotechnology in the development of African genetic toxicology.

    Science.gov (United States)

    Anwar, Wagida A

    2005-09-01

    Developing countries are currently going through a transitional phase facing the new challenges of globalization and its potential negative impact. Research policy should highlight the need to mobilize resources for human resource development, networking, improved research culture, information sharing, and pragmatic use of research findings. Advancement in molecular genetics whether at the educational or research level should greatly progress in developing countries so as to improve diagnosis, treatment, understanding of disease risk factors, and prevention. Currently, there is a growing interest to genetic toxicology research, the use of different biomarkers, and genetic susceptibility testing, which can contribute effectively in risk assessment. Africa has unique environmental exposures and public health circumstances, which make it ideal for environmental mutagenicity and carcinogenicity research. There are exposures to chemical genotoxicants (e.g., automobile exhaust, pesticides, metals, and cytotoxic drugs) and to lifestyle factors (e.g., consumption of tobacco products) that have been linked to the expression of biological effects and to increased risk for cancer. Infections can be associated with cancer development when the environmental factors interact with the infection and lead to the enhancement of the carcinogenic process. The high prevalence of viral pathogens and the improper use of pesticides may endanger biological functions beyond those for which they originally manufactured. Biomarkers are used to detect the effects of pesticides before adverse clinical health occurs. The scientific community plays a crucial role in understanding the environmental causes of human health problems and through its collaboration with communities, industries, and government agencies can help in resolving health problems.

  6. An eye for possibilities in the development of children with cerebral palsy

    DEFF Research Database (Denmark)

    Bøttcher, Louise

    2010-01-01

    Taking children with Cerebral Palsy (CP) as an example, the article seeks an understanding of children with disabilities that connects neuropsychological theories of neural development with the situated cognition perspective and the child as an active participant in its social practices. The early...

  7. Administrative Circular No. 2 (Rev. 7) - Recruitment, appointment and possible developments regarding the contractual position of staff members

    CERN Multimedia

    2015-01-01

    Administrative Circular No. 2 (Rev. 7), entitled "Recruitment, appointment and possible developments regarding the contractual position of staff members", approved by the Director-General following discussion at the Standing Concertation Committee meeting held on 17 February 2015 is available via the following link: AC No. 2 (Rev.7).   This revised circular cancels and replaces Administrative Circular No. 2 (Rev. 6), entitled "Recruitment, appointment and possible developments regarding the contractual position of staff members" and dated January 2015. The circular was revised in order to implement the amendment to Article R II 1.17 of the Staff Regulations, which introduces the possibility of extending limited-duration (LD) contracts up to a maximum total duration of eight years from the previous duration of five years. The award of indefinite contracts will continue to be subject to the outcome of a competitive process. Department Head Of...

  8. Visible Light Responsive Catalysts Using Quantum Dot-Modified Ti02 for Air and Water Purification

    Science.gov (United States)

    Coutts, Janelle L.; Levine, Lanfang H.; Richards, Jeffrey T.; Hintze, paul; Clausen, Christian

    2012-01-01

    The method of photocatalysis utilizing titanium dioxide, TiO2, as the catalyst has been widely studied for trace contaminant control for both air and water applications because of its low energy consumption and use of a regenerable catalyst. Titanium dioxide requires ultraviolet light for activation due to its band gap energy of 3.2 eV. Traditionally, Hg-vapor fluorescent light sources are used in PCO reactors and are a setback for the technology for space application due to the possibility of Hg contamination. The development of a visible light responsive (VLR) TiO2-based catalyst could lead to the use of solar energy in the visible region (approx.45% of the solar spectrum lies in the visible region; > 400 nm) or highly efficient LEDs (with wavelengths > 400 nm) to make PCO approaches more efficient, economical, and safe. Though VLR catalyst development has been an active area of research for the past two decades, there are few commercially available VLR catalysts; those that are available still have poor activity in the visible region compared to that in the UV region. Thus, this study was aimed at the further development of VLR catalysts by a new method - coupling of quantum dots (QD) of a narrow band gap semiconductor (e.g., CdS, CdSe, PbS, ZnSe, etc.) to the TiO2 by two preparation methods: 1) photodeposition and 2) mechanical alloying using a high-speed ball mill. A library of catalysts was developed and screened for gas and aqueous phase applications, using ethanol and 4-chlorophenol as the target contaminants, respectively. Both target compounds are well studied in photocatalytic systems serve as model contaminants for this research. Synthesized catalysts were compared in terms of preparation method, type of quantum dots, and dosage of quantum dots.

  9. Foundation Flash Catalyst

    CERN Document Server

    Goralski, Greg

    2010-01-01

    This book offers an introduction to Flash Catalyst for designers with intermediate to advanced skills. It discusses where Catalyst sits within the production process and how it communicates with other programs. It covers all of the features of the Flash Catalyst workspace, teaching you how to create designs from scratch, how to build application designs and add functionality, and how to master the Catalyst/Flex workflow. * Introduces Flash Catalyst * Focuses on production process * Covers the interrelation between Flash Catalyst and Photoshop/Illustrator/Flex/Flash What you'll learn Starting f

  10. Catalyst and electrode research for phosphoric acid fuel cells

    Science.gov (United States)

    Antoine, A. C.; King, R. B.

    1987-01-01

    An account is given of the development status of phosphoric acid fuel cells' high performance catalyst and electrode materials. Binary alloys have been identified which outperform the baseline platinum catalyst; it has also become apparent that pressurized operation is required to reach the desired efficiencies, calling in turn for the use of graphitized carbon blacks in the role of catalyst supports. Efforts to improve cell performance and reduce catalyst costs have led to the investigation of a class of organometallic cathode catalysts represented by the tetraazaannulenes, and a mixed catalyst which is a mixture of carbons catalyzed with an organometallic and a noble metal.

  11. [Service robots in elderly care. Possible application areas and current state of developments].

    Science.gov (United States)

    Graf, B; Heyer, T; Klein, B; Wallhoff, F

    2013-08-01

    The term "Service robotics" describes semi- or fully autonomous technical systems able to perform services useful to the well-being of humans. Service robots have the potential to support and disburden both persons in need of care as well as nursing care staff. In addition, they can be used in prevention and rehabilitation in order to reduce or avoid the need for help. Products currently available to support people in domestic environments are mainly cleaning or remote-controlled communication robots. Examples of current research activities are the (further) development of mobile robots as advanced communication assistants or the development of (semi) autonomous manipulation aids and multifunctional household assistants. Transport robots are commonly used in many hospitals. In nursing care facilities, the first evaluations have already been made. So-called emotional robots are now sold as products and can be used for therapeutic, occupational, or entertainment activities.

  12. Possibilities for entrepreneurship development in organic production of Vukovar-Srijem County

    Directory of Open Access Journals (Sweden)

    Jadranka Deže

    2016-11-01

    Full Text Available Organic agriculture is a farming system which tends to be ethically acceptable, ecologically clean, socially fair and economically profitable agricultural production. Entrepreneuship is supposed to start production and business activities as well as create new products and added value. Entrepreneurship in agriculture is important for human nutrition, production of raw materials and its connections to services, and it is a generator of economy development. The aim of this research is to determine the conditions and development prospects of entrepreneurship in organic farming of Vukovar-Srijem County. During the paper preparation, scientific literature and appropriate internet sources were used along with statistical data from the official websites of the Ministry of Agriculture and Vukovar-Srijem County. According to the research results, organic agricultural production continuously and intensively grows in the Republic of Croatia. In 2015, 3061 farmers who produce organic food on 75,882 hectares were registered. When it comes to Vukovar-Srijem County, there are 63 farmers involved in organic farming on 1944 hectares of agricultural land, which represents 2.56% of the total area under organic farming in the Republic of Croatia. Entrepreneurs should increase their production in order to achieve better competitiveness on market and they should be more focused on the processing of organic products in order to achieve higher selling prices compared to primary agricultural products. CEPOR Vukovar is recognized for the promotion and advancement of entrepreneurship in organic farming in Vukovar-Srijem County, whereas perspectives in the development of organic farming have been associated with development projects funded by the EU.

  13. Structured Perovskite-Based Catalysts and Their Application as Three-Way Catalytic Converters—A Review

    Directory of Open Access Journals (Sweden)

    Sylvain Keav

    2014-07-01

    Full Text Available Automotive Three-Way Catalysts (TWC were introduced more than 40 years ago. Despite that, the development of a sustainable TWC still remains a critical research topic owing to the increasingly stringent emission regulations together with the price and scarcity of precious metals. Among other material classes, perovskite-type oxides are known to be valuable alternatives to conventionally used TWC compositions and have demonstrated to be suitable for a wide range of automotive applications, ranging from TWC to Diesel Oxidation Catalysts (DOC, from NOx Storage Reduction catalysts (NSR to soot combustion catalysts. The interest in these catalysts has been revitalized in the past ten years by the introduction of the concept of catalyst regenerability of perovskite-based TWC, which is in principle well applicable to other catalytic processes as well, and by the possibility to reduce the amounts of critical elements, such as precious metals without seriously lowering the catalytic performance. The aim of this review is to show that perovskite-type oxides have the potential to fulfil the requirements (high activity, stability, and possibility to be included into structured catalysts for implementation in TWC.

  14. Hydrocarbon reforming catalysts and new reactor designs for compact hydrogen generators

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, A.; Schwab, E.; Urtel, H. [BASF SE, Ludwigshafen (Germany); Farrauto, R. [BASF Catalysts LLC, Iselin, NJ (United States)

    2010-12-30

    A hydrogen based future energy scenario will use fuel cells for the conversion of chemically stored energy into electricity. Depending upon the type of fuel cell, different specifications will apply for the feedstock which is converted in the cell, ranging from very clean hydrogen for PEM-FC's to desulfurized methane for SOFC and MCFC technology. For the foreseeable future, hydrogen will be supplied by conventional reforming, however operated in compact and dynamic reformer designs. This requires that known catalyst formulations are offered in specific geometries, giving flexibility for novel reactor design options. These specific geometries can be special tablet shapes as well as monolith structures. Finally, also nonhydrocarbon feedstock might be used in special applications, e.g. bio-based methanol and ethanol. BASF offers catalysts for the full process chain starting from feedstock desulfurization via reforming, high temperature shift, low temperature shift to CO fine polishing either via selective oxidation or selective methanation. Depending upon the customer's design, most stages can be served either with precious metal based monolith solutions or base metal tablet solutions. For the former, we have taken the automobile catalyst monolith support and extended its application to the fuel cell hydrogen generation. Washcoats of precious metal supported catalysts can for example be deposited on ceramic monoliths and/or metal heat exchangers for efficient generation of hydrogen. Major advantages are high through puts due to more efficient heat transfer for catalysts on metal heat exchangers, lower pressure drop with greater catalyst mechanical and thermal stability compared to particulate catalysts. Base metal tablet catalysts on the other hand can have intrinsic cost advantages, larger fractions of the reactor can be filled with active mass, and if produced in unconventional shape, again novel reactor designs are made possible. Finally, if it comes to

  15. Possibility of star (pyramid) dune development in the area of bimodal wind regime

    Science.gov (United States)

    Biejat, K.

    2012-04-01

    Star (pyramid) dunes are the largest aeolian landforms. They can occur in three types - simple, complex and compound. Development of this type of dunes is usually connected with multidirectional or complex wind regimes. The aim of this study was to verify a hypothesis that the star dunes can also develop by a bimodal wind regime and by local modifications of nearsurface wind flow directions. Field study was performed on Erg Chebbi, in southern Morocco. Several star and transverse dunes were selected for the study of their shape. The star dunes were analysed concerning their type and position in the dune field. This erg contains all of three types of star dunes together with transverse dunes. The regional wind data show that there are two dominant wind directions - NE (Chergui) and SW (Saheli). To determine the difference in shape of star dunes, we performed topographic surveying by GPS RTK. The results allowed to create 3D models of star dunes. The models were used to determine metric characteristics of star dunes, including area of dune basis, volume, and slope angles. On the basis of 3D models, primary, secondary and, on the compound dunes, tertiary arms were determined. Primary arms on each type of star dunes, as well as crestlines of transverse dunes, have dominant orientation NW-SE, perpendicular to two dominant wind directions. This clearly confirms that star dunes of Erg Chebbi develop by a bimodal wind regime In contrast to primary arms, subsidiary (secondary and tertiary) arms are not connected to general wind regime. The secondary arms of star dunes occur to be differentially developer. There are more subsidiary arms on SW sides in comparison to the E sides of the dunes where inclination of slopes is constant. It can be therefore inferred that sand has been supplied predominantly from SW direction. This is supported by distribution of the dunes on the erg. Most compound star dunes compose a chain along the E margin of the erg. Comparison of compound star

  16. Bioenergy in Ukraine-Possibilities of rural development and opportunities for local communities

    Energy Technology Data Exchange (ETDEWEB)

    Raslavicius, Laurencas, E-mail: Laurencas.Raslavicius@gmail.com [UAB ' Axis Technologies' , Kulautuvos g. 45a, 47190 Kaunas (Lithuania); Grzybek, Anna [EC Baltic Renewable Energy Centre (EC BREC), Gdansk (Poland); Institute of Technology and Life Sciences, ul. Rakowiecka 32, PL-02-532 Warsaw (Poland); Dubrovin, Valeriy [National University of Life and Environmental Sciences of Ukraine, Institute of Ecobiotechnologies and Bioenergy, Heroiv Oborony Street 15, 03041 Kyiv (Ukraine)

    2011-06-15

    This review paper deals with colligated aspects of the BioPlus Project (ERA-ARD) implemented by Institute of Technology and Life Sciences (Poland) and Lithuanian University of Agriculture Institute of Agro-Engineering (Lithuania) in cooperation with National University of Life and Environmental Sciences of Ukraine Institute of Ecobiotechnologies and Bioenergy (Ukraine). The drawn inferences intended to be an auxiliary material for policy makers and can briefly indicate on direction of the regional development of rural Ukraine, focusing on: (i) country's specific and sub-regional assessments of renewable energy potentials and spheres of its application; (ii) identification of major barriers for the expansion of renewable energy technologies and policy guidance to overcome those barriers; (iii) recommendations for future actions and strategies concerning renewable energy in Ukraine. The article concludes that low contribution of bioenergy towards rural development is to a large extent driven by energy policy that inhibits the delivery and use of modern energy sources in rural Ukraine. Consequently, an incentive for achieving bioenergy's future that has greater relevance to development of the Ukraine's regions requires a mix of policy tools and institutional actions, briefly summarized in this paper. - Highlights: > We examine current status and the potentials of bioenergy in Ukraine. > We examine major barriers for the expansion of bioenergy technologies in Ukraine. > Ukraine has the highest potential for renewable energy production in Europe. > Bioenergy sector of UA requires better mix of policy tools and institutional actions. > Cost-competitiveness and financing of technologies and projects are major challenges.

  17. The "first digit law" - A hypothesis on its possible impact on medicine and development aid.

    Science.gov (United States)

    Pollach, Gregor; Brunkhorst, Frank; Mipando, Mwapatsa; Namboya, Felix; Mndolo, Samson; Luiz, Thomas

    2016-12-01

    The "first digit law" or "Benford's law" is a mathematical distribution discovered by Simon Newcomb and Frank Benford. It states, that the probability of the leading number d (d∈{1,…,9}) in many natural datasets follows: P (d)=log10 (d+1)-log10 (d)=log10 (1+1/d). It was successfully used through tax authorities and "forensic accounting" in order to detect fraud and other irregularities. Benfords law was almost neglected for its use outside financial accounting. The planning for health care systems in developing countries is extremely dependant on good, valid data. Whether you plan the catchment area for the future district hospitals, the number of health posts, the staff establishment for the central hospital or the drug budget in the Ministry. The "first digit law" can be used in medicine, public health, physiology and development aid to unmask questionable data, to discover unexpected challenges, difficulties in the data collection process, loss through corruption and criminal fraud. Our hypothesis suggests, that the "first digit law" is a cost effective tool, which is easy to use for most people in the medical profession, which does not really needs complicated statistical software and can be used on the spot, even in the resource restricted conditions of developing countries. Several preconditions (like the size of the data set and its reach over more than two dimensions) have to be fulfilled, but then Benfords law can be used by any clinician, physiologist, public health specialist or aid consultant without difficulties and without deeper statistical knowledge in the four steps, we suggest in this article. The consequences will be different depending on the level (local regional, national, continental, international) on which you will use the law. All levels will be enabled to get insight into the validity of the data-challenges for the other levels without the help of trained statisticians or accountants. We believe that the "first digit law" is a vastly

  18. Possible paths towards sustainable tourism development in a high-mountain resort

    Directory of Open Access Journals (Sweden)

    Laurent Arcuset

    2009-12-01

    Full Text Available This text starts from the teachings stemming from an evaluation of the tourist practices in the light of sustainable tourism principles, realized in 2004 within the framework of a national network piloted by the French Agency of Touristic Engineering (today ODIT France, for the ski resort of Valloire, first-generation resort in the Maurienne, which development and modernization in the 2000s kept pace with a vast real estate program. The article investigates the stakes and difficulties of the implementation of sustainable development in Valloire, asks the question of the "cultural revolution" which the actors should achieve to change the model of economic development, and suggest some tracks to reach there. The local approach of "sustainable tourism", indeed, seems for the moment rather to aim - as in many other high mountain ski resorts - towards a more environmental management of the basic urban functions than a real questioning of a tourist model based upon the triptych development of the ski slopes, securizing of the snow resource and touristic real estate programs.Ce texte part des enseignements issus d’une évaluation des pratiques touristiques à l’aune des principes du tourisme durable, réalisée en 2004 dans le cadre d’un réseau national piloté par l’Agence Française d’Ingénierie Touristique (aujourd’hui ODIT France, pour la station de Valloire, station de première génération de Maurienne dont le développement et la modernisation dans les années 2000 sont allés de pair avec un vaste programme immobilier. L’article explore les enjeux et les difficultés de la mise en œuvre du développement durable à Valloire, pose la question de la « révolution culturelle » que les acteurs devraient accomplir pour changer de modèle de développement économique, et suggère quelques pistes pour y parvenir. L’approche locale du « tourisme durable », en effet, semble pour l’heure plutôt tendre – comme dans bien

  19. The possible role of the ubiquitin proteasome system in the development of atherosclerosis in diabetes

    Directory of Open Access Journals (Sweden)

    sasso Ferdinando

    2007-10-01

    -resistance, post-prandial hyperglycemia and chronic hyperglycemia play a role in the atherosclerotic process and may require intervention 67. Moreover, it is important to recognize that these risk factors frequently "cluster" inindividual patients and possibly interact with each other, favouring the atherosclerosis progression toward plaque instability. Thus, a fundamental question is, "which is the common soil hypothesis that may unifying the burden of all these factors on atherosclerosis of diabetic patients? Because evidences suggest that insulin-resistance, diabetes and CHD share in common a deregulation of ubiquitin-proteasome system (UPS, the major pathway for nonlysosomal intracellular protein degradation in eucaryotic cells 89, in this review ubiquitin-proteasome deregulation is proposed as the common persistent pathogenic factor mediating the initial stage of the atherosclerosis as well as the progression to complicated plaque in diabetic patients.

  20. The moral development of medical students: a pilot study of the possible influence of medical education.

    Science.gov (United States)

    Self, D J; Schrader, D E; Baldwin, D C; Wolinsky, F D

    1993-01-01

    Medicine endorses a code of ethics and encourages a high moral character among doctors. This study examines the influence of medical education on the moral reasoning and development of medical students. Kohlberg's Moral Judgment Interview was given to a sample of 20 medical students (41.7% of students in that class). The students were tested at the beginning and at the end of their medical course to determine whether their moral reasoning scores had increased to the same extent as other people who extend their formal education. It was found that normally expected increases in moral reasoning scores did not occur over the 4 years of medical education for these students, suggesting that their educational experience somehow inhibited their moral reasoning ability rather than facilitating it. With a range of moral reasoning scores between 315 and 482, the finding of a mean increase from first year to fourth year of 18.5 points was not statistically significant at the P moral reasoning scores and age, gender, Medical College Admission Test scores, or grade point average scores. Along with a brief description of Kohlberg's cognitive moral development theory, some interpretations and explanations are given for the findings of the study.

  1. OLTENIA NORTHERN MEDICAL TOURISM AND DEVELOPMENT IN TERMS OF THE POSSIBILITY OF REGIONAL SUSTAINABILITY

    Directory of Open Access Journals (Sweden)

    Constanta Enea

    2013-06-01

    Full Text Available Health tourism in Romania is at the beginning - it exists, develops in some areas, shy, we do not boast of many tourists who come to us for such services, however, the data provided by NATA, now a year or two there were over 60,000 people who came to our country for health tourism. Of course, data are incomplete because not all tourists coming to say. But it seems that 250 million would have entered this area. Potential exists, and curiosity and demand for Romania there. But there is enough interest for the development of such tourism. Medical tourism (also called medical travel, health tourism or global healthcare is a term initially coined by travel agencies and the media to rapidly growing phenomenon of crossing international borders to obtain health care services. The paper tries to highlight the chances for Romania, more specifically, Northern Oltenia become a specific area of medical tourism or medical tourism practiced in other countries, to local patient survival chance.

  2. Rethinking blood components and patients: Patient blood management. Possible ways for development in France.

    Science.gov (United States)

    Folléa, Gilles

    2016-01-01

    As any therapeutic means, blood transfusion requires regular evaluation, particularly for its indications, effectiveness and risks. A better awareness of the risks of blood transfusion, the availability of randomized clinical trials, the evolution of the quality of blood components, and the economic constraints shared by all countries, all have led to rethink both transfusion therapy as a whole and the organization of the transfusion chain from donor to recipient. In this context, patient blood management (PBM) appears as an evidence-based, patient centred, multidisciplinary approach, aiming to optimise the care of patients who might need transfusion and consequently the use of blood products. This paper presents updated scientific bases of PBM and the three pillars founding it. As PBM is developing fast in other European countries, this review proposes ways to explore for its development in France. It finally proposes to integrate PBM in a wider and coordinated approach of the blood supply management, with tools to improve the effectiveness and efficiency of the transfusion chain, starting with the needs of the patients and ending with an optimum treatment of the patient, including the appropriate number of blood components of the required quality. A better understanding, implementation and assessment of this coordinated global approach, allowing to adapt donor collections to the patients' needs in compliance with safety requirements for patients and donors, in a coordinated way, will certainly be a major challenge for transfusion medicine in the near future, for the benefit of patients, donors and all other stakeholders involved in the transfusion chain.

  3. Immobilized Ruthenium Catalyst for Carbon Dioxide Hydrogenation

    Institute of Scientific and Technical Information of China (English)

    Ying Min YU; Jin Hua FEI; Yi Ping ZHANG; Xiao Ming ZHENG

    2006-01-01

    Three kinds of cross linked polystyrene resin (PS) supported ruthenium complexes were developed as catalysts for the synthesis of formic acid from carbon dioxide hydrogenation. Many factors, such as the functionalized supports, solvents and ligands, could influence their activities and reuse performances greatly. These immobilized catalysts also offer the industrial advantages such as easy separation.

  4. [Master Transcription Regulators Specifying Cell-Lineage Fates in Development As Possible Therapeutic Targets in Oncology].

    Science.gov (United States)

    Kondratyeva, L G; Vinogradova, T V; Chernov, I P; Sverdlov, E D

    2015-11-01

    The transformation of normal precursors into cancer cells is an intricately regulated, multistep process. The master regulatory genes that play a crucial role in the process of organism development may also play a key role in carcinogenesis. From such a point of view, cancer is not simply a genetic disease that is due to a progressive accumulation of mutation--it is also a disorder of the developmental system of the tissue in which cancer emerges. Master regulators and their genes disturb stem cell differentiation upon mutation and thus may serve as targets for cancer therapy, in addition to the classic oncogenes and suppressors of tumor formation. This review is an attempt to give a modern concept of master genes and their functions in adult stem cells of the organism and in carcinogenesis, with pancreatic cancer as an example.

  5. Pancreas and beta-cell development: from the actual to the possible.

    Science.gov (United States)

    Murtaugh, L Charles

    2007-02-01

    The development of insulin-producing pancreatic beta (beta)-cells represents the culmination of a complex developmental program. Cells of the posterior foregut assume a pancreatic identity, cells within the expanding pancreatic primordia adopt an endocrine fate, and a subset of these precursors becomes competent to generate beta-cells. Postnatally, beta-cells are primarily maintained by self-duplication rather than new differentiation. Although major gaps in our knowledge still persist, experiments across several organisms have shed increasing light on the steps of beta-cell specification and differentiation. Increasing our understanding of the extrinsic, as well as intrinsic, mechanisms that control these processes should facilitate efforts to regenerate this important cell type in humans.

  6. Study on the possibilities of dedicated CAD applications development for the furniture industry

    Directory of Open Access Journals (Sweden)

    Ioan Mocian

    2009-12-01

    Full Text Available This paper presents the results of a research for finding the best solutions to design and develop the CAD applications for the furniture industry. The solutions considered exclude the use of complementary software such as AutoCAD, Inventor or SolidWorks, the main target being stand-alone, cheap and easy to use solutions. The paper presents concepts of components typing in the furniture industry and thepossibilities to construct complex combinations of furniture using these typed components. A dedicated application for designing certain types of bookshelves is also presented. The application is stand-alone and it was written in the object oriented programming language VB.NET. The study has been carried out with partners from the furniture industry, whose opinions and views on this matter were of great help.

  7. Possibilities for the further development of combined cycle power station technology. Moeglichkeiten zur Weiterentwicklung der Kombi-Kraftwerkstechnik

    Energy Technology Data Exchange (ETDEWEB)

    Adlhoch, W. (Rheinbraun AG, Koeln (Germany)); Bolt, N. (KEMA, Arnheim (Netherlands))

    1994-07-01

    Power plant technology has to make a contribution towards the reduction of the global damage of the climate due to the greenhouse effect. Ways of reducing CO[sub 2] emissions are found in the first place in better utilization of the primary energy used. Possibilities for further development of combined cycle power plant technology are described with the aid of selected examples. In addition to theoretical considerations, the paper also describes current development projects, which demonstrate the potential of process engineering and component development. (orig.)

  8. Optimal catalyst curves: Connecting density functional theory calculations with industrial reactor design and catalyst selection

    DEFF Research Database (Denmark)

    Jacobsen, C.J.H.; Dahl, Søren; Boisen, A.

    2002-01-01

    For ammonia synthesis catalysts a volcano-type relationship has been found experimentally. We demonstrate that by combining density functional theory calculations with a microkinetic model the position of the maximum of the volcano curve is sensitive to the reaction conditions. The catalytic...... ammonia synthesis activity, to a first approximation, is a function only of the binding energy of nitrogen to the catalyst. Therefore, it is possible to evaluate which nitrogen binding energy is optimal under given reaction conditions. This leads to the concept of optimal catalyst curves, which illustrate...... the nitrogen binding energies of the optimal catalysts at different temperatures, pressures, and synthesis gas compositions. Using this concept together with the ability to prepare catalysts with desired binding energies it is possible to optimize the ammonia process. In this way a link between first...

  9. In situ Transmission Electron Microscopy of catalyst sintering

    DEFF Research Database (Denmark)

    DeLaRiva, Andrew T.; Hansen, Thomas Willum; Challa, Sivakumar R.

    2013-01-01

    Recent advancements in the field of electron microscopy, such as aberration correctors, have now been integrated into Environmental Transmission Electron Microscopes (TEMs), making it possible to study the behavior of supported metal catalysts under operating conditions at atomic resolution. Here......, we focus on in situ electron microscopy studies of catalysts that shed light on the mechanistic aspects of catalyst sintering. Catalyst sintering is an important mechanism for activity loss, especially for catalysts that operate at elevated temperatures. Literature from the past decade is reviewed...

  10. On the Late Development and Possible Astronomical Origin of the Gyroscope

    Science.gov (United States)

    Brecher, Kenneth

    2013-01-01

    The invention of the gyroscope is usually attributed to the French physicist Jean-Bernard-Leon Foucault in the year 1852. He certainly created the word and also used his gyroscope to demonstrate the rotation of the Earth. However, the gyroscope was actually invented around 1812 by the German scientist Johann Bohnenberger who called his device simply the “machine”. Bohnenberger was a professor of astronomy and mathematics and published a book about astronomy in 1811. Several other scientists, including American physicist Walter R. Johnson (who called his apparatus the “rotascope”), independently invented the gyroscope. Each of these devices employed a central object (sphere or disc) that could spin on a shaft. This object was placed between three independent gimbals, two of which could move freely. Bohnenberger’s “machine” has much the same appearance as an armillary sphere. Those astronomical devices had been produced for at least the preceding three centuries and were widely dispersed and well known throughout Europe. They were used to display the apparent motion of celestial bodies. However, armillary spheres were used only as simulations of celestial appearances, not as actual demonstrations of physical phenomena. It is not known if the inertial properties of armillary spheres (and also of terrestrial and celestial globes) had been studied before about 1800. Nonetheless, as a matter of practice, gimbal systems similar to those found in gyroscopes were used on ships to level oil lamps at least as early as the sixteenth century AD. And the ideas behind armillary spheres date back at least a millennium before that. So why did the invention of the gyroscope in its modern form take such a long time when the individual underlying components had been around and utilized for some two millennia? Perhaps because the understanding of angular momentum, including its conservation, was not developed until the start of the 19th century and also because the

  11. Health, Islam and Alternative Capitalism. Three possible Key Factors in Developing Somaliland

    Directory of Open Access Journals (Sweden)

    Daria Zizzola

    2012-02-01

    Full Text Available The main aim of this paper is to investigate the socio, political and economic dynamics that have occurred in Somaliland in the last decades. Even though this country is still unrecognized by the international community, Somaliland’s economy has undertaken an enduring growth, above all in the private entrepreneurial sector. The author argues that religion has had an important role in the Somali cultural and social identification. According to this assumption, the article analyzes the Islamic factor by showing how it has led to the creation of many alternative connections supported by mutual trust and religious solidarity among involved communities. These connections are somehow fulfilling the absence of political legitimacy while progressively substituting conventional routes of intra-national negotiation, like diplomacy. To confirm this tendency, specific arguments are drawn from Somaliland’s health sector. The health care system is considered a preferential index to evaluate the level of national development. Above all, the private non-profit sector gives some evidence of the Somali capacity of running competitive private businesses while multiplying simultaneously their resources and suppliers with a consequent increase in autonomy and efficiency. This successful compromise bears the fruits of Somali engagement and can be identified by their inexhaustible adaptability to adverse conditions and their ability to avoid, not deny, the rational rules imposed by external actors and their ostensible, insurmountable interests.

  12. Wilsonville Advanced Coal Liquefaction Research and Development Facility, Wilsonville, Alabama. Topical report No. 14. Catalyst activity trends in two-stage coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    1984-02-01

    The Two Stage Coal Liquefaction process became operational at Wilsonville in May 1981, with the inclusion of an H-OIL ebullated-bed catalytic reactor. The two stage process was initially operated in a nonintegrated mode and has recently been reconfigurated to fully integrate the thermal and the catalytic stages. This report focuses on catalyst activity trends observed in both modes of operation. A literature review of relevant catalyst screening studies in bench-scale and PDU units is presented. Existing kinetic and deactivation models were used to analyze process data over an extensive data base. Based on the analysis, three separate, application studies have been conducted. The first study seeks to elucidate the dependence of catalyst deactivation rate on type of coal feedstock used. A second study focuses on the significance of catalyst type and integration mode on SRC hydrotreatment. The third study presents characteristic deactivation trends observed in integrated operation with different first-stage thermal severities. In-depth analytical work was conducted at different research laboratories on aged catalyst samples from Run 242. Model hydrogenation and denitrogenation activity trends are compared with process activity trends and with changes observed in catalyst porosimetric properties. The accumulation of metals and coke deposits with increasing catalyst age, as well as their distribution across a pellet cross-section, are discussed. The effect of catalyst age and reactor temperature on the chemical composition of flashed bottoms product is addressed. Results from regenerating spent catalysts are also presented. 35 references, 31 figures, 18 tables.

  13. [Social psychological determinants of the formation of medical students' professional identity. Possibilities of development].

    Science.gov (United States)

    Csörsz, Ilona

    2011-03-20

    Systematic observations regarding techniques of medical career-socialization has hardly ever appeared in Hungarian technical literature yet. Focusing on the need for practical medical training the author elaborated a career-socialization program consisting of a three-level, three-branch training technique. This consisted of a Junior Bálint-group, an imaginative visualization technique, and an expressive, drama-pedagogical working method completed with a projective technique. This career-socialization program focuses on the physician's personality, capability-expansion in relationship management, and practicing a set of professional behavior-roles. During the empirical observations connected to the work the author examined medical students' patient-representation, their relation to the patients, and the development of the physician's professional character. Within the frames of this three-level, three-branch training technique program it enables us to observe which training technique is able to reveal all those psychological qualities that can contribute to the conformation of the representations, thus to the process of career-socialization in the most effective way. The content-analyses of the cases of Junior Bálint-groups (n = 60) revealed that the most frequent problems are fear of intimacy, of bodily contact, communication with patients in a chronic or terminal state, and the fear of medical practice. The content-analyses of imaginary patient-images (n = 62) with Rorschach-signs confirmed that the psychological burdens mentioned above are the most serious problems for medical students. The process-, and content-analyses of drama-games, the integrative healing contact training groups (n = 74) showed that group work primarily intensifies the relationship responsiveness, the ability to adopt the other's (the patient's) viewpoints, and enables an involuntary and distressless identification with the patient and the physician, both agents in the healing relationship

  14. Possible ecologically based ways of preserving and developing the Ukrainian Carpathians

    Directory of Open Access Journals (Sweden)

    V. І. Nikolaichuk

    2016-02-01

    . Structural changes in the economy of the region are expected to strengthen the recreational value of the Ukrainian Carpathians for the public not only in our country but also in Central and Eastern Europe, reducing the technogenic loading. International cooperation of all countries of the Carpathian region is imperative. The development of tourism in the Carpathians is highly promising, but this should be civilized tourism, taking into account the environmental sustainability of the recreational areas and protected areas.

  15. Possibilities for recovery and prospects of the Serbian chemical industry in the light of sustainable development

    Directory of Open Access Journals (Sweden)

    Đukić Petar M.

    2014-01-01

    such as food, construction, energy, and many others, from the medium technologies domain, as well as those from the high technologies domain, such as bio-medical, pharmaceutical or cosmetic technologies. In such manner, the participation of chemical industry in the re-industrialisation of Serbia should not be observed only as a contribution to the recovery of industry, but as a factor of sustainable development in all its components, economic, social and ecological.

  16. Cenomanian-Turonian aquifer of central Israel, its development and possible use as a storage reservoir

    Science.gov (United States)

    Schneider, Robert

    1964-01-01

    The Cenomanian-Turonian formations constitute a highly permeable dolomite and limestone aquifer in central Israel. The aquifer is on the west limb of an anticlinorium that trends north-northeast. In places it may be as much as 800 meters thick, but in the report area, largely the foothills of the Judean-Ephraim Mountains where the water development is most intensive, its thickness is generally considerably less. In some places the aquifer occurs at or near the land surface, or it is covered by sandy and gravelly coastal-plain deposits. However, in a large part of the area, it is overlain by as much as 400 meters of relatively impermeable strata, and it is probably underlain by less permeable Lower Cretaceous strata. In general the aquifer water is under artesian pressure. The porosity of the aquifer is characterized mainly by solution channels and cavities produced by jointing and faulting. In addition to the generally high permeability of the aquifer, some regions, which probably coincide with ancient drainage patterns and (or) fault zones, have exceptionally high permeabilities. The source of most of the water in the aquifer is believed to be rain that falls on the foothills area. The westward movement of ground water from the mountainous outcrop areas appears to be impeded by a zone of low permeability which is related to structural and stratigraphic conditions along the western side of the mountains. Gradients of the piezometric surface are small, and the net direction of water movement is westward and northwestward under natural conditions. Locally, however, the flow pattern may be in other directions owing to spatial variations in permeability in the aquifer, the location of natural discharge outlets, and the relation of the aquifer to adjacent geologic formations. There probably is also a large vertical component of flow. Pumping has modified the flow pattern by producing several irregularly shaped shallow depressions in the piezometric surface although, to

  17. Pd Close Coupled Catalyst

    Institute of Scientific and Technical Information of China (English)

    Zhong Hua SHI; Mao Chu GONG; Yao Qiang CHEN

    2006-01-01

    A catalyst comprised novel high surface area alumina support was prepared to control emission of automobiles. The results showed that prepared catalyst could satisfy the requirements of a high performance close coupled catalyst for its good catalytic activity at low temperature and good stability at high temperature.

  18. Catalyst and Fuel Interactions to Optimize Endothermic Cooling

    Science.gov (United States)

    2016-08-30

    tungsten and molybdenum carbides exhibit enhanced catalytic activity for reactions such as benzene hydrogenation, ammonia synthesis , hydrodehalogenation and...and coking of the catalysts. Finally, there was significant methods development in the areas of theory, catalyst synthesis and characterization, and...theory, catalyst synthesis and characterization, and methods for catalytic reaction analysis. Endothermic fuels, catalysis, DFT, clusters, X-ray

  19. Copper Replaces Tin: A Copper based Gelling Catalyst for Poly-Urethane from Discarded Motherboard

    OpenAIRE

    Parasar, Bibudha; Jing, Gao Wen; Yuan, Dandan; Kun, Wang; Wang, Peng; Dasgupta, Arijit; Sahasrabudhe, Atharva; Barman, Soumitra; Yuan, Rongxin; Roy, Soumyajit

    2013-01-01

    A discarded motherboard based eco-friendly copper catalyst has been programmed to replace the industrially used tin based catalyst DBTDL. The catalyst has been characterized by UV-Vis spectroscopy, FT-IR and TEM. Using the catalyst reaction conditions is optimized and under the optimized condition, both polyurethane and polyurethane foam are prepared, thus proving the generality of the catalyst to be used in industries. A possible mechanism has also been proposed.

  20. Nanostructured Basic Catalysts: Opportunities for Renewable Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Conner, William C; Huber, George; Auerbach, Scott

    2009-06-30

    This research studied and developed novel basic catalysts for production of renewable chemicals and fuels from biomass. We focused on the development of unique porous structural-base catalysts zeolites. These catalysts were compared to conventional solid base materials for aldol condensation, that were being commercialized for production of fuels from biomass and would be pivotal in future biomass conversion to fuels and chemicals. Specifically, we had studied the aldolpyrolysis over zeolites and the trans-esterification of vegetable oil with methanol over mixed oxide catalysts. Our research has indicated that the base strength of framework nitrogen in nitrogen substituted zeolites (NH-zeolites) is nearly twice as strong as in standard zeolites. Nitrogen substituted catalysts have been synthesized from several zeolites (including FAU, MFI, BEA, and LTL) using NH3 treatment.

  1. The semantic development of IE *weid- to the meaning ‘know’ and the possible contrast with IE *gneh3-

    Directory of Open Access Journals (Sweden)

    Trinidad Silva

    2012-12-01

    Full Text Available This study is an attempt to trace the semantic development of the ie root *weid- and the possible contrast with the lexical pair *gneh3-. The analysis covers cross-linguistic comparison assessed diachronically in connection with historical linguistic phenomena and synchronically by the examination of two particular Greek authors, Homer and Plato, and some examples in the use of living languages such as Spanish, French and German.

  2. Propene metathesis over silica-supported tungsten oxide catalyst-catalyst induction mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Basrur, A.G.; Patwardhan, S.R.; Vyas, S.N. (Indian Inst. of Tech., Bombay (India))

    1991-01-01

    The propene metathesis reaction was studied from the point of view of elucidating the mechanism of catalyst induction and establishing conditions for maximum activity. Instrumental techniques such as ESR, IR, and TPD were used to study the various aspects. During catalyst induction, trace quantities of acetone and acetaldehyde were detected in the product stream, indicating that lattice oxygen from tungsten oxide might be responsible for these products. Induction appeared to proceed via two steps since pretreatment of the catalyst with nitrogen and hydrogen yielded a decreased amount of acetone in the latter case whereas acetaldehyde remained unaffected. ESR studies indicated some interaction between tungsten oxide and silica at the catalyst preparatory stage as well as stabilization of reduced tungsten species on the catalyst after its use and regeneration. Catalyst activity appeared to depend on conditions of pretreatment. Change in nitrogen pretreatment temperature from 500 to 600{sup o}C resulted in transition from strong to negligible external mass transfer behavior of the catalyst. TPD studies in this context showed possible loss of lattice oxygen from tungsten oxide under the above-mentioned conditions of catalyst pretreatment. ESR studies indicated the reduction of WO{sub 3} to a nonstoichiometric oxidation state. Hence catalytic activity appears to be related to the nonstoichiometric state of tungsten oxide, which may be WO{sub 2.9} (as deduced from the blue-violet color of the used catalyst).

  3. The cluster beam route to model catalysts and beyond.

    Science.gov (United States)

    Ellis, Peter R; Brown, Christopher M; Bishop, Peter T; Yin, Jinlong; Cooke, Kevin; Terry, William D; Liu, Jian; Yin, Feng; Palmer, Richard E

    2016-07-01

    The generation of beams of atomic clusters in the gas phase and their subsequent deposition (in vacuum) onto suitable catalyst supports, possibly after an intermediate mass filtering step, represents a new and attractive approach for the preparation of model catalyst particles. Compared with the colloidal route to the production of pre-formed catalytic nanoparticles, the nanocluster beam approach offers several advantages: the clusters produced in the beam have no ligands, their size can be selected to arbitrarily high precision by the mass filter, and metal particles containing challenging combinations of metals can be readily produced. However, until now the cluster approach has been held back by the extremely low rates of metal particle production, of the order of 1 microgram per hour. This is more than sufficient for surface science studies but several orders of magnitude below what is desirable even for research-level reaction studies under realistic conditions. In this paper we describe solutions to this scaling problem, specifically, the development of two new generations of cluster beam sources, which suggest that cluster beam yields of grams per hour may ultimately be feasible. Moreover, we illustrate the effectiveness of model catalysts prepared by cluster beam deposition onto agitated powders in the selective hydrogenation of 1-pentyne (a gas phase reaction) and 3-hexyn-1-ol (a liquid phase reaction). Our results for elemental Pd and binary PdSn and PdTi cluster catalysts demonstrate favourable combinations of yield and selectivity compared with reference materials synthesised by conventional methods.

  4. [Sudden cardiac death: the possible role of latent myocardial ischemia in the mechanisms of its formation and development].

    Science.gov (United States)

    Bobrov, V O; Bilonozhko, O H; Stepanenko, A P; Zotov, S Iu; Mymrenko, S M; Zinchenko, Iu V; Osos, I P; Verezhnykova, H P; Dolzhenko, M M; Lohvynenko, A O

    2000-01-01

    An analysis was performed of comprehensive (non-invasive and invasive) observations of IHD patients presenting with atherosclerotic lesions of coronary arteries of the heart and atypical clinical picture of the condition. A possibility was shown of a significant obstruction of arteries of the heart in atypical localization of pain and in those patients who had not derived much benefit from nitroglycerin during the development of ischemia and measures instituted against it. Inadequate reaction to nitroglycerin may be explained by specificities of changes in the vegetative nervous system, by the hemodynamics reaction, and, in the first place, by a propensity for developing tachycardia under physical loading, emotional stress, and after ingestion of nitroglycerin.

  5. Latent catalyst; Senzaisei shokubai

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Epoxy resin, an important function material to support such main industries as electric and electronic devices, automobiles, civil engineering, and building construction, is demanded of development of single liquid type resin having excellent quick hardening performance and storage stability. This requirement comes from environmental problems with an intention of saving energies and reducing resin wastes. The Company, using freely its independent phase separation technology that controls molecular structure of catalysts, developed a latent catalyst having excellent storage stability and high-temperature quick hardening performance. Its major features may be summarized as follows: (1) excellent storage stability at room temperature keeping the product stable for 2.5 months or longer (2 days in conventional products); (2) quick hardening performance hardening the resin in seven seconds at 150 degrees C (equivalent to conventional products); and (3) excellent insulation performance of hardened resin at 140 degrees C of 7 times 10 {sup 13} (ohm) (center dot) cm (2 times 10 {sup 12} (ohm) (center dot) cm in conventional products) (translated by NEDO)

  6. Process development for the separation and recovery of Mo and Co from chloride leach liquors of petroleum refining catalyst by solvent extraction

    Energy Technology Data Exchange (ETDEWEB)

    Banda, Raju [Department of Advanced Material Science and Engineering, Mokpo National University, Chonnam 534-729 (Korea, Republic of); Sohn, Seong Ho [Korea Institute of Industrial Technology, Incheon Technology Service Centre, 7-47, Songdo-dong, Incheon 406-840 (Korea, Republic of); Lee, Man Seung, E-mail: mslee@mokpo.ac.kr [Department of Advanced Material Science and Engineering, Mokpo National University, Chonnam 534-729 (Korea, Republic of)

    2012-04-30

    Highlights: Black-Right-Pointing-Pointer Separation of Mo and Co from HCl solution was investigated by solvent extraction. Black-Right-Pointing-Pointer The solution was synthetic leaching solution of spent HDS catalysts. Black-Right-Pointing-Pointer Extraction with TOPO led to complete separation of Mo. Black-Right-Pointing-Pointer Alamine 308 can separate Co from the Mo free raffinate. Black-Right-Pointing-Pointer Recovery percentage of both metals was higher than 99%. - Abstract: The separation and recovery of Mo and Co from the synthetic chloride leach liquors of petroleum refining catalyst has been investigated by employing TOPO and Alamine 308 as extractants. The synthetic leach liquor contained Mo 394 mg/L, Al 1782 mg/L, Co 119 mg/L in 3 M HCl. The separation of Mo from Co and Al was achieved with 0.05 M TOPO in Escaid 110 and complete stripping of Mo was attained with combination of 0.1 M NH{sub 4}OH and 0.05 M (NH{sub 4}){sub 2}CO{sub 3}. After separation of molybdenum, cobalt can be selectively extracted by Alamine 308 from Mo free raffinate after adjusting the concentration of chloride ion to 5 M by adding AlCl{sub 3}. The back-extraction of cobalt was obtained easily from loaded Alamine 308 with acidified water (pH = 1.0). McCabe-Thiele diagrams were constructed from the extraction and stripping experiments of each element (Mo and Co). From the batch simulation of the counter-current extraction and stripping experiments, it was confirmed that Mo and Co recovery of 99.4% and 99.1% respectively was obtained from the synthetic leach liquor of the chloride solutions. Finally a hydrometallurgical process flow sheet was developed.

  7. Recent developments in microbial oils production: a possible alternative to vegetable oils for biodiesel without competition with human food?

    Directory of Open Access Journals (Sweden)

    Gwendoline Christophe

    2012-02-01

    Full Text Available Since centuries vegetable oils are consumed as human food but it also finds applications in biodiesel production which is attracting more attention. But due to being in competition with food it could not be sustainable and leads the need to search for alternative. Nowdays microbes-derived oils (single cell oils seem to be alternatives for biodiesel production due to their similar composition to that of vegetable oils. However, the cold flow properties of the biodiesel produced from microbial oils are unacceptable and have to be modified by an efficient transesterification. Glycerol which is by product of transesterification can be valorised into some more useful products so that it can also be utilised along with biodiesel to simplify the downstream processing. The review paper discusses about various potent microorganisms for biodiesel production, enzymes involved in the lipid accumulation, lipid quantification methods, catalysts used in transesterification (including enzymatic catalyst and valorisation of glycerol.

  8. Phosphine-Free EWG-Activated Ruthenium Olefin Metathesis Catalysts

    Science.gov (United States)

    Grela, Karol; Szadkowska, Anna; Michrowska, Anna; Bieniek, Michal; Sashuk, Volodymyr

    Hoveyda-Grubbs catalyst has been successfully fine-tuned by us in order to increase its activity and applicability by the introduction of electron-withdrawing groups (EWGs) to diminish donor properties of the oxygen atom. As a result, the stable and easily accessible nitro-substituted Hoveyda-Grubbs catalyst has found a number of successful applications in various research and industrial laboratories. Some other EWG-activated Hoveyda-type catalysts are commercially available. The results described herewith demonstrate that the activity of ruthenium (Ru) metathesis catalysts can be enhanced by introduction of EWGs without detriment to catalysts stability. Equally noteworthy is the observation that different Ru catalysts turned out to be optimal for different applications. This shows that no single catalyst outperforms all others in all possible applications.

  9. Trends and Possible Future Developments in Global Forest-Product Markets—Implications for the Swedish Forest Sector

    Directory of Open Access Journals (Sweden)

    Ragnar Jonsson

    2011-01-01

    Full Text Available This paper analyzes trends and possible future developments in global wood-product markets and discusses implications for the Swedish forest sector. Four possible futures, or scenarios, are considered, based on qualitative scenario analysis. The scenarios are distinguished principally by divergent futures with respect to two highly influential factors driving change in global wood-product markets, whose future development is unpredictable. These so-called critical uncertainties were found to be degrees to which: (i current patterns of globalization will continue, or be replaced by regionalism, and (ii concern about the environment, particularly climate change, related policy initiatives and customer preferences, will materialize. The overall future of the Swedish solid wood-product industry looks bright, irrespective of which of the four possible futures occurs, provided it accommodates the expected growth in demand for factory-made, energy-efficient construction components. The prospects for the pulp and paper industry in Sweden appear more ambiguous. Globalization is increasingly shifting production and consumption to the Southern hemisphere, adversely affecting employment and forest owners in Sweden. Further, technical progress in information and communication technology (ICT is expected to lead to drastic reductions in demand for newsprint and printing paper. Chemical pulp producers may profit from a growing bio-energy industry, since they could manufacture new, high-value products in integrated bio-refineries. Mechanical pulp producers cannot do this, however, and might suffer from higher prices for raw materials and electricity.

  10. Supported Copper, Nickel and Copper-Nickel Nanoparticle Catalysts for Low Temperature Water-Gas-Shift Reaction

    Science.gov (United States)

    Lin, Jiann-Horng

    Hydrogen is being considered worldwide as a future replacement for gasoline, diesel fuel, natural gas in both the transportation and non-transportation sectors. Hydrogen is a versatile energy carrier that can be produced from a variety of widely available primary energy sources, including coal, natural gas, biomass, solar, wind, and nuclear power. Coal, the most abundant fossil fuel on the planet, is being looked at as the possible future major source of H2, due to the development of the integrated gasification combined cycle (IGCC) and integrated gasification fuel cell technologies (IGFC). The gasification of coal produces syngas consisting of predominately carbon monoxide and hydrogen with some remaining hydrocarbons, carbon dioxide and water. Then, the water-gas shift reaction is used to convert CO to CO2 and additional hydrogen. The present work describes the synthesis of model Cu, Ni and Cu-Ni catalysts prepared from metal colloids, and compares their behavior in the WGS reaction to that of traditional impregnation catalysts. Initially, we systematically explored the performance of traditional Cu, Ni and Cu-Ni WGS catalysts made by impregnation methods. Various bimetallic Cu-Ni catalysts were prepared by supported impregnation and compared to monometallic Cu and Ni catalysts. The presence of Cu in bimetallic catalysts suppressed undesirable methanation side reaction, while the Ni component was important for high WGS activity. Colloidal Cu, Ni and Cu-Ni alloy nanoparticles obtained by chemical reduction were deposited onto alumina to prepare supported catalysts. The resulting Cu and Ni nanoparticle catalysts were found to be 2.5 times more active in the WGS reaction per unit mass of active metal as compared to catalysts prepared by the conventional impregnation technique. The powder XRD and HAADF-STEM provided evidence supporting the formation of Cu-Ni particles containing the Cu core and Cu-Ni alloy shell. The XPS data indicated surface segregation of Cu in

  11. MMC-High Propylene Selectivity DCC Catalyst

    Institute of Scientific and Technical Information of China (English)

    Li Zheng; Xie Chaogang; Luo Yibin; Zhao Liuzhou; Shu Xingtian

    2007-01-01

    RIPP has developed the third generation novel DCC catalysts aimed at increasing the propylene yield, named as the MMC series catalysts. This catalyst is of the MFI structure composed of the ZSP zeolite as the main active component, which has higher capability for producing low-carbon olefins, in particular the propylene. The commercial application of this catalyst at SINOPEC Anqing Petrochemical Company has revealed that the adoption of the MMC-2 catalyst has resulted in a 1.6-4.0 percentages increase in propylene yield under basically similar conditions in terms of the feedstock property and process operating regime coupled with reduction in gasoline olefin content and increase in aromatic content to improve the gasoline quality.

  12. Alternative deNOx catalysts and technologies

    DEFF Research Database (Denmark)

    Due-Hansen, Johannes

    . The commercial catalyst used for the selective catalytic reduction (SCR) of nitrogen oxides exhibits high activity and selectivity towards N2. However, the vanadia-titania-based catalyst used is very sensitive to deactivation by alkali-species (primarily potassium), which are typically present in high amounts...... in the flue gas when biomass is combusted. By co-firing with large amounts of CO2-neutral straw or wood (tomeet stringent CO2 emission legislation), the lifetime of the traditional SCR catalyst is thus significantly reduced due to the presence of deactivating species originating from the fuel. To develop...... active species distributed on the support were investigated, such as iron, copper and vanadium oxides. However, based on the catalysts performance in the SCR reaction and their resistances towards potassium, the most promising candidate of the formulations studied was the vanadia-loaded catalyst, i.e. V2...

  13. Development of PHR fix-bed residue hydrodemetallization catalysts%PHR系列固定床渣油加氢脱金属催化剂的研制

    Institute of Scientific and Technical Information of China (English)

    程涛; 赵愉生; 谭青峰; 崔瑞利

    2016-01-01

    为有效解决渣油加氢脱金属过程中沥青质和胶质等大分子物质的扩散、反应和沉积难题,提高催化剂脱杂质活性和容金属能力,对催化剂设计进行了优化集成,开发出了一系列催化剂制备关键技术,研制成功4个牌号的脱金属催化剂(PHR-101、PHR-102、PHR-103、PHR-104)。以非酸性的黏结剂代替胶溶酸实现氧化铝的无酸成型,大幅提高了载体孔容和孔径;采用复合扩孔方法制备出双峰孔结构载体,大于1000nm 孔比例达到16.4%,改善了催化剂孔道结构;实现活性金属组分的非均匀负载,优化活性分布,促进杂质向催化剂内部的扩散和沉积。小型装置2000h 评价结果表明,催化剂脱杂质(脱金属、脱硫、脱残炭)活性与稳定性明显高于常规催化剂。模拟工业运转条件下,在1L中型装置上进行了5500h长周期试验,结果表明,加氢全馏分产品金属含量满足指标要求,催化剂预期寿命达到8000h以上,满足工业应用要求。14个月的挂篮试验表明,与工业催化剂相比,所开发催化剂的金属容纳能力更高,金属沉积更为均匀。%In order to solve the diffusion,reaction and deposition problems of high molecular materials such as asphaltenes and resins,and to improve the catalyst’s activity and metal capacity during the process of residue hydrodemetallization,we developed a series of key technologies and 4 grades residue hydrodemetallization catalysts(PHR-101,PHR-102,PHR-103,PHR-104)by optimized catalyst design. Non-acidic binder was employed to replace the traditional acids to prepare alumina support with substantially increased pore volume and size. Dual-peak-pore-structure support,with 16.4% pore size above 1000nm,was obtained through compound pore expanding method to improve catalysts’ pore structure. And non-uniform distribution of active metal components was achieved to promote impurities to diffuse to and

  14. ANALYSIS OF THE POSSIBILITY OF USING HYDROLOGICAL MODELS IN STRATEGIC ENVIRONMENTAL ASSESSMENT OF LOCAL SPATIAL DEVELOPMENT PLANS

    Directory of Open Access Journals (Sweden)

    Mariusz Sojka

    2014-10-01

    Full Text Available The paper presents the possibility of application of the hydrological model HEC-HMS in the development of a strategic environmental assessment of local spatial development plans on surface water. The practical possibility of using simulation models of catchment response to high intensity precipitation is shown on the example of the Różany Potok watercourse catchment which is subject to rapid urbanization process. The area of Różany Potok catchment is 8.1 km2 and a stream length is 5.57 km. In the years 1992–2012 there was a significant increase in impervious areas in the catchment of about 5.2 to 16%. In addition, new local spatial development plans are prepared within the catchment area. The implementation of their records may contribute to the increase in the proportion of impervious areas to over 20%. The increase in the share of impervious areas in the catchment area and traditional approach of precipitation water management can lead to doubling flood flows and increase the risk of local flooding.

  15. Possible Greenland

    DEFF Research Database (Denmark)

    2012-01-01

    Organizing in Greenland is a complex matter. We have been on an arctic odyssey exploring the different aspects of the Greenlandic reality and have created a publication in which a wide range of Greenlandic and international profiles and stakeholders give their opinion and visions for the future...... development in Greenland. By creating a platform for a wide range of ideas about the Possible Greenland to be discussed now and in the future, we give Greenlanders and Greenlandic decision makers access to the greatest amount of possible solutions to the challenges they are facing. We look more closely...... at Greenland's structure, and ask some threshold questions. Which aspects of society are rooted in our human hardware? And, if we had the rare opportunity to build a new nation, what would we choose for ourselves? We hope this will inspire an open, imaginative and thoroughly human discussion about how...

  16. Advances in HDS catalysts design: relation between catalyst structure and feed composition

    NARCIS (Netherlands)

    Kagami, Narinobu

    2006-01-01

    The aim of this work is to propose a better understanding of ultra deep HDS for diesel, to contribute to the development of advanced catalysts. The characterization of catalyst structure was examined by XRD, TPR, TPS and Raman spectroscopy. The ranking of catalytic activities were tested using vario

  17. Mesoporous Molecular Sieves as Supports for Metathesis Catalysts

    Science.gov (United States)

    Balcar, Hynek; Cejka, Jirí

    Mesoporous molecular sieves represent a new family of inorganic oxides with regular nanostructure, large surface areas, large void volumes, and narrow pore size distribution of mesopores. These materials offer new possibilities for designing highly active and selective catalysts for olefin metathesis and metathesis polymerization. Siliceous sieves MCM-41, MCM-48, SBA-15, and organized mesoporous alumina (OMA) were used as supports for preparation of new molybdenum and rhenium oxide catalysts, as well as for heterogenization of well-defined homogeneous catalysts.

  18. Monte Carlo simulation of the PEMFC catalyst layer

    Institute of Scientific and Technical Information of China (English)

    WANG Hongxing; CAO Pengzhen; WANG Yuxin

    2007-01-01

    The performance of the polymer electrolyte membrane fuel cell (PEMFC) is greatly controlled by the structure of the catalyst layer.Low catalyst utilization is still a significant obstacle to the commercialization of the PEMFC.In order to get a fundamental understanding of the electrode structure and to find the limiting factor in the low catalyst utilization,it is necessary to develop the mechanical model on the effect of catalyst layer structure on the catalyst utilization and the performance of the PEMFC.In this work,the structure of the catalyst layer is studied based on the lattice model with the Monte Carlo simulation.The model can predict the effects of some catalyst layer components,such as Pt/C catalyst,electrolyte and gas pores,on the utilization of the catalyst and the cell performance.The simulation result shows that the aggregation of conduction grains can greatly affect the degree of catalyst utilization.The better the dispersion of the conduction grains,the larger the total effective area of the catalyst is.To achieve higher utilization,catalyst layer components must be distributed by means of engineered design,which can prevent aggregation.

  19. Host response to Foot- and Mouth Disease infection in cattle; possible implications for the development of “carriers”

    DEFF Research Database (Denmark)

    Stenfeldt, Carolina; Heegaard, Peter M. H.

    in persistence of FMD in cattle are not fully known. A series of animal experiments, with the aim of investigating the innate immune response, and possible implications for the development of persistently infected FMD carrier-animals in cattle has been performed. Bull calves of 4-5 months of age were infected...... spreads rapidly amongst susceptible animals. The host response involves initial activation of the innate immune response, followed by subsequent production of high titres of anti-FMDV antibodies in the circulation. Antibodies are effective in clearing virus from the circulation, but in a proportion......Foot-and-mouth disease (FMD) is a viral disease with severe financial implications for agricultural industries and the trade of animal products in affected countries. Any cloven hoofed animal species may become infected, and ruminants, especially cattle and buffalo, may develop into persistently...

  20. Residential and commercial space heating and cooling with possible greenhouse operation; Baca Grande development, San Luis Valley, Colorado. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Goering, S.W.; Garing, K.L.; Coury, G.E.; Fritzler, E.A.

    1980-05-01

    A feasibility study was performed to evaluate the potential of multipurpose applications of moderate-temperature geothermal waters in the vicinity of the Baca Grande community development in the San Luis Valley, Colorado. The project resource assessment, based on a thorough review of existing data, indicates that a substantial resource likely exists in the Baca Grande region capable of supporting residential and light industrial activity. Engineering designs were developed for geothermal district heating systems for space heating and domestic hot water heating for residences, including a mobile home park, an existing motel, a greenhouse complex, and other small commercial uses such as aquaculture. In addition, a thorough institutional analysis of the study area was performed to highlight factors which might pose barriers to the ultimate commercial development of the resource. Finally, an environmental evaluation of the possible impacts of the proposed action was also performed. The feasibility evaluation indicates the economics of the residential areas are dependent on the continued rate of housing construction. If essentially complete development could occur over a 30-year period, the economics are favorable as compared to existing alternatives. For the commercial area, the economics are good as compared to existing conventional energy sources. This is especially true as related to proposed greenhouse operations. The institutional and environmental analyses indicates that no significant barriers to development are apparent.

  1. Open Flexible Lifelong Learning As A Catalyst For 
Sustainable Development In Sub-Saharan Africa

    OpenAIRE

    OLAKULEHIN, Felix Kayode

    2015-01-01

    Educational provision in developing sub-Saharan Africa states has been severely hindered by the hydra-headed problems of access, cost and quality. Amidst these challenges is the pledge of regional and national education policymakers and development planners to ensure that there is maximum access equitable and qualitative education for all (EFA) in Africa. There is also a burning need for improved literacy levels and functional education, in order to overcome the development deficits that are ...

  2. Resin Catalyst Hybrids

    Institute of Scientific and Technical Information of China (English)

    S. Asaoka

    2005-01-01

    @@ 1Introduction: What are resin catalyst hybrids? There are typically two types of resin catalyst. One is acidic resin which representative is polystyrene sulfonic acid. The other is basic resin which is availed as metal complex support. The objective items of this study on resin catalyst are consisting of pellet hybrid, equilibrium hybrid and function hybrid of acid and base,as shown in Fig. 1[1-5].

  3. Catalyst and process development for hydrogen preparation from future fuel cell feedstocks. Quarterly report, April 1-June 30, 1980. [Pt/Pd

    Energy Technology Data Exchange (ETDEWEB)

    Yarrington, R M; Feins, I R; Hwang, H S

    1980-07-01

    Phase II of the contract, which involved catalyst preparation and evaluation, was nearly completed this quarter. Phase III, which calls for the design and construction of a fuel processor, was started. During the quarter, four types of tests were run on the small scale catalyst screening unit. The operating line for coke-free operations was found to be approximately between 0.41 to 0.44 O/sub 2//C level. Screening at lower O/sub 2//C levels led to problems with plugging. In other tests, increased severity for screening steam reforming catalysts was obtained by doubling the space velocity. Another series of tests were run to determine the gas composition from the catalytic partial oxidation (CPO) section and to evaluate two CPO catalysts. In the other series of tests, catalysts were aged for about 20 hours using a propane, steam, and air mixture before testing with No. 2 oil for another five hours. This latter test has been used to study Pt/Rh catalysts made with various supports. Differences were readily determined for Pt/Rh supported on alpha alumina and Pt/Rh supported on stabilized alumina. This test method will find continued use in evaluating metal-support interactions. Several samples must be evaluated by this method before aging runs are made in the larger unit. After leaching alumina from a used Pt/Rh catalyst, the x-ray diffraction pattern showed the presence of a Pt-Rh alloy in the metal residue. Experiments were run to show that the alloy was formed in the reactor during testing and not during catalyst preparation. A larger version of the ATR reactor has been designed and major components are on order. Completion of the construction phase is scheduled for the next quarter.

  4. Nanostructured hydrotreating catalysts for electrochemical hydrogen evolution.

    Science.gov (United States)

    Morales-Guio, Carlos G; Stern, Lucas-Alexandre; Hu, Xile

    2014-09-21

    Progress in catalysis is driven by society's needs. The development of new electrocatalysts to make renewable and clean fuels from abundant and easily accessible resources is among the most challenging and demanding tasks for today's scientists and engineers. The electrochemical splitting of water into hydrogen and oxygen has been known for over 200 years, but in the last decade and motivated by the perspective of solar hydrogen production, new catalysts made of earth-abundant materials have emerged. Here we present an overview of recent developments in the non-noble metal catalysts for electrochemical hydrogen evolution reaction (HER). Emphasis is given to the nanostructuring of industrially relevant hydrotreating catalysts as potential HER electrocatalysts. The new syntheses and nanostructuring approaches might pave the way for future development of highly efficient catalysts for energy conversion.

  5. Ceramic catalyst materials

    Energy Technology Data Exchange (ETDEWEB)

    Sault, A.G.; Gardner, T.J. [Sandia National Laboratories, Albuquerque, NM (United States); Hanprasopwattanna, A.; Reardon, J.; Datye, A.K. [Univ. of New Mexico, Albuquerque, NM (United States)

    1995-08-01

    Hydrous titanium oxide (HTO) ion-exchange materials show great potential as ceramic catalyst supports due to an inherently high ion-exchange capacity which allows facile loading of catalytically active transition metal ions, and an ability to be cast as thin films on virtually any substrate. By coating titania and HTO materials onto inexpensive, high surface area substrates such as silica and alumina, the economics of using these materials is greatly improved, particularly for the HTO materials, which are substantially more expensive in the bulk form than other oxide supports. In addition, the development of thin film forms of these materials allows the catalytic and mechanical properties of the final catalyst formulation to be separately engineered. In order to fully realize the potential of thin film forms of titania and HTO, improved methods for the deposition and characterization of titania and HTO films on high surface area substrates are being developed. By varying deposition procedures, titania film thickness and substrate coverage can be varied from the submonolayer range to multilayer thicknesses on both silica and alumina. HTO films can also be formed, but the quality and reproducibility of these films is not nearly as good as for pure titania films. The films are characterized using a combination of isopropanol dehydration rate measurements, point of zero charge (PZC) measurements, BET surface area, transmission electron microscopy (TEM), and elemental analysis. In order to assess the effects of changes in film morphology on catalytic activity, the films are being loaded with MoO{sub 3} using either incipient wetness impregnation or ion-exchange of heptamolybdate anions followed by calcining. The MoO{sub 3} is then sulfided to form MOS{sub 2}, and tested for catalytic activity using pyrene hydrogenation and dibenzothiophene (DBT) desulfurization, model reactions that simulate reactions occurring during coal liquefaction.

  6. LC-finer catalyst testing. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Garg, D.; Bronfenbrenner, J.C.

    1983-09-01

    The activity and aging rate of modified Shell 324 Ni-Mo-Al catalyst were studied in ICRC's process development unit (PDU) under SRC-I Demonstration Plant hydroprocessing conditions. The studies determined variations in SRC conversion, hydrocarbon gas production, hydrogen consumption, and heteroatom removal at both constant and increasing reaction temperatures. Samples of spent catalyst were analyzed to ascertain the reasons for catalyst deactivation. Finally, the PDU hydroprocessing results were compared with those generated at Lummus and Wilsonville pilot plants. 14 references, 25 figures, 16 tables.

  7. Development of an eco-protocol for seaweed chlorophylls extraction and possible applications in dye sensitized solar cells

    Science.gov (United States)

    Armeli Minicante, S.; Ambrosi, E.; Back, M.; Barichello, J.; Cattaruzza, E.; Gonella, F.; Scantamburlo, E.; Trave, E.

    2016-07-01

    Seaweeds are a reserve of natural dyes (chlorophylls a, b and c), characterized by low cost and easy supply, without potential environmental load in terms of land subtraction, and also complying with the requirements of an efficient waste management policy. In particular, the brown seaweed Undaria pinnatifida is a species largely present in the Venice Lagoon area, and for it a removal strategy is actually mandatory. In this paper, we set-up an eco-protocol for the best extraction and preparation procedures of the pigment, with the aim of finding an easy and affordable method for chlorophyll c extraction, exploring at the same time the possibility of using these algae within local sustainable management integrated strategies, among which the possible use of chlorophylls as a dye source in dye sensitized solar cells (DSSCs) is investigated. Experimental results suggest that the developed protocols are useful to optimize the chlorophyll c extraction, as shown by optical absorption spectroscopy measurements. The DSSCs built with the chlorophyll extracted by the proposed eco-protocol exhibit solar energy conversion efficiencies are similar to those obtained following extraction protocols with larger environmental impacts.

  8. Process development for the separation and recovery of Mo and Co from chloride leach liquors of petroleum refining catalyst by solvent extraction.

    Science.gov (United States)

    Banda, Raju; Sohn, Seong Ho; Lee, Man Seung

    2012-04-30

    The separation and recovery of Mo and Co from the synthetic chloride leach liquors of petroleum refining catalyst has been investigated by employing TOPO and Alamine 308 as extractants. The synthetic leach liquor contained Mo 394 mg/L, Al 1782 mg/L, Co 119 mg/L in 3 M HCl. The separation of Mo from Co and Al was achieved with 0.05 M TOPO in Escaid 110 and complete stripping of Mo was attained with combination of 0.1M NH(4)OH and 0.05 M (NH(4))(2)CO(3). After separation of molybdenum, cobalt can be selectively extracted by Alamine 308 from Mo free raffinate after adjusting the concentration of chloride ion to 5 M by adding AlCl(3). The back-extraction of cobalt was obtained easily from loaded Alamine 308 with acidified water (pH=1.0). McCabe-Thiele diagrams were constructed from the extraction and stripping experiments of each element (Mo and Co). From the batch simulation of the counter-current extraction and stripping experiments, it was confirmed that Mo and Co recovery of 99.4% and 99.1% respectively was obtained from the synthetic leach liquor of the chloride solutions. Finally a hydrometallurgical process flow sheet was developed.

  9. Highly Durable Catalysts for Ignition of Advanced Monopropellants Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposed SBIR Phase I addresses the development of catalysts and technology for the ignition of advanced monopropellants consisting of mixtures of...

  10. Glycerol conversion into value added chemicals over bimetallic catalysts in supercritical carbon dioxide

    Science.gov (United States)

    Hidayati, Luthfiana N.; Sudiyarmanto, Adilina, Indri B.

    2017-01-01

    Development of alternative energy from biomass encourage the experiments and production of biodiesel lately. Biodiesel industries widely expand because biodiesel as substitute of fossil fuel recognized as promising renewable energy. Glycerol is a byproduct of biodiesel production, which is resulted 10% wt average every production. Meanwhile, carbon dioxide is a gas that is very abundant amount in the atmosphere. Glycerol and carbon dioxide can be regarded as waste, possibly will produce value-added chemical compounds through chemically treated. In this preliminary study, conversion of glycerol and carbon dioxide using bimetallic catalyst Ni-Sn with various catalyst supports : MgO, γ-Al2O3, and hydrotalcite. Catalysts which have been prepared, then physically characterized by XRD, surface area and porosity analysis, and thermal gravity analysis. Catalytic test performance using supercritical carbon dioxide conditions. Furthermore, the products were analyzed by GC. The final product mostly contained of propylene glycol and glycerol carbonate.

  11. Reaction Chemistry of W-Mn/SiO2 Catalyst for the Oxidative Coupling of Methane

    Institute of Scientific and Technical Information of China (English)

    Shuben Li

    2003-01-01

    Reaction chemistry of the OCM reaction on W-Mn/SiO2 catalyst has been reviewed in thisaccount. Initial activity and selectivity, stability in a long-term reaction, reaction at elevated pressures anda modelling test in a stainless-steel fluidized-bed reactor show that W-Mn/SiO2 has promising performancefor the development of an OCM process that directly produces ethylene from natural gas. A study onsurface catalytic reaction kinetics and used catalyst structure characterization revealed a possible reasonwhy C2 and COx selectivity changed during the long-term reaction. Further improvement of the catalystcomposition and preparation method should be a future direction of study on OCM reaction over W-Mn/SiO2 catalyst.

  12. [Possibilities of surgical treatment of lesions of the organs of the reproductive system and disorders of sexual development].

    Science.gov (United States)

    Okulov, A B; Negmadzhanov, B B; Bogdanova, E A; Iusim, E M; Glybina, T M; Godlevskiĭ, D N; Urinov, M Ia; Matveev, Iu K

    1990-01-01

    The authors describe the data on clinico-laboratory and instrumental examinations and surgical treatment of about 5,000 children with different reproductive organ injuries including complex patterns of abnormal sexual differentiation. The designed diagnostic programs made it possible to distribute patients into groups and according to the disease entities in conformity with the classification suggested. It is emphasized that in the developing science concerned with sex, it is necessary to distinguish an area pertaining to childhood, namely pediatric andrology, and to delineate its subject matter and tasks. Skilled assistance can be rendered by a specialized center. A broad spectrum of improved masculinizing (including the design of an artificial phallus) and feminizing (including the design of an artificial vagina from the rectosigmoid segment of the colon) is provided. The catamnestic data are evaluated.

  13. International labor migration in the social and economic development of Ukraine: trends, negative consequences and possible solutions

    Directory of Open Access Journals (Sweden)

    K.V. Shymanska

    2015-03-01

    Full Text Available The article describes the prerequisites for the development of labor migration in Ukraine. The main trends and negative consequences of international migration for Ukraine, including the growing problem of human trafficking, national aging, loss of fiscal revenues and increased strain on the pension fund have been defined. Statistics on labor migration indicators and the number of Ukrainian victims of trafficking in the world have been analyzed. In the conclusions possible solutions of overcoming social and economic problems associated with external labor migration, have been grounded, including monitoring internal and external migration data on its changes, signing international agreements on migrant workers’ abroad employment and social protection, improving higher education targeting to the needs of national and regional labor markets.

  14. Consonance and Dissonance in a Study Abroad Program as a Catalyst for Professional Development of Pre-Service Teachers

    Science.gov (United States)

    Brindley, Roger; Quinn, Suzanne; Morton, Mary Lou

    2009-01-01

    This research examines the experiences of elementary and early childhood pre-service teachers from the U.S. engaged in a month long study abroad internship program in England. Using data from participants written journals, we use a hermeneutic approach to interrogate their evolving sense of professional development and their understanding of…

  15. Privatization and economic liberalization: the role of the entrepreneur as a catalyst for economic development in transition economies

    NARCIS (Netherlands)

    Dibrell, Clay; Danskin Englis, Paula; Kedia, Ben L.; Lakatos, Gergo M.

    2008-01-01

    Many nations with transition economies are attempting to develop their national competitiveness through such processes as privatisation of state owned enterprises (SOEs) and/or the use of economic liberalisation (e.g. lessening of tariffs, industry regulations, etc.) to spur economic growth and deve

  16. Alloy catalyst material

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention relates to a novel alloy catalyst material for use in the synthesis of hydrogen peroxide from oxygen and hydrogen, or from oxygen and water. The present invention also relates to a cathode and an electrochemical cell comprising the novel catalyst material, and the process use...

  17. Catalyst for Ammonia Oxidation

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a bimetallic catalyst for ammonia oxidation, a method for producing a bimetallic catalyst for ammonia oxidation and a method for tuning the catalytic activity of a transition metal. By depositing an overlayer of less catalytic active metal onto a more catalytic...

  18. Reducible oxide based catalysts

    Science.gov (United States)

    Thompson, Levi T.; Kim, Chang Hwan; Bej, Shyamal K.

    2010-04-06

    A catalyst is disclosed herein. The catalyst includes a reducible oxide support and at least one noble metal fixed on the reducible oxide support. The noble metal(s) is loaded on the support at a substantially constant temperature and pH.

  19. Remote possibilities

    Energy Technology Data Exchange (ETDEWEB)

    Butler, M. [Inmarsat (United Kingdom)

    2004-08-01

    The paper examines how a new generation of small mobile satellite data services are delivering possibilities for competitive advantage in the coal industry. Inmarsat has developed a range of products that bring access to high-speed, secure IP data from locations not supported by terrestrial/cellular networks or fixed satellite services. It launched its regional broadband global area network BGAN service in late 2002. The sizing of a small notebook PC and light-weight, the new device brings secure access to corporate networks and databases, email and the internet at speeds of up to 144 Kbit/s. The next generation of Inmarsat satellites will enable the BGAN service to provide communications at speeds up to 432 Kbit/s.

  20. Possible Roles of B1 Cells and Environmental Estrogens (Endocrine Disruptors in the Development of Autoimmune Diseases

    Directory of Open Access Journals (Sweden)

    Sho Ishikawa

    2005-01-01

    Full Text Available Autoimmune diseases as well as type-I allergic diseases have markedly increased in the past 30 years. Environmental estrogens or endocrine disruptors are possibly involved in the etiology of the increase in autoimmune diseases as one of environmental factors. In aged BWF1 mice, a murine model for SLE, B lymphocyte chemoattractant (BLC/CXCL13 is ectopically and highly expressed in target organs such as the thymus and kidney. B1 cells, a specialized cell population that are distinguished from conventional B cells (B2 cells by their origin, cell surface phenotype, unique tissue distribution, self-reactivity, etc., preferentially migrate towards BLC. Aberrant B1 cell trafficking to the target organs may result in activation of autoreactive CD4 T cells, autoantibody production, and impaired mucosal immunity in the gut during the development of SLE. Interestingly, B1 cells show a higher sensitivity to environmental estrogens than conventional B (B2 cells to produce autoantibodies. Thus, B1 cell can be a useful target for evaluating the pathological significance of environmental estrogens in the development of autoimmune diseases.

  1. Exclusive breastfeeding of Swedish children and its possible influence on the development of obesity: a prospective cohort study

    Directory of Open Access Journals (Sweden)

    Ludvigsson Jonas F

    2008-10-01

    Full Text Available Abstract Background Overweight and obesity are increasing among children all over the world. Socio-economic factors may influence the development of overweight and obesity in childhood, and it has been proposed that breastfeeding may protect against obesity. The aim of our study was to examine the relationship between exclusive breastfeeding and obesity when potential confounders, such as socioeconomic factors, are considered. Methods The data analyzed was from ABIS (All Babies in Southeast Sweden, a prospective cohort study. All parents with children born between October 1, 1997 and October 1, 1999 in Southeast Sweden (n = 21,700 were asked to participate. Parents were asked to answer periodic questionnaires from the time of the child's birth (n = 16,058 until he/she was five years of age (n = 7,356. Cutoffs for overweight and obesity were defined according to Cole et al, age and gender adjusted. Short-term exclusive breastfeeding was defined as Results At five years of age, 12.9% of the children in the study wereoverweight and 4.3% were obese. At the age of three months, 78.4% of the children were being breastfed exclusively. The median exclusive breastfeeding duration was four months. High maternal BMI > 30 (AOR = 1.07; CI = 1.05–1.09; P Conclusion We cannot exclude the possibility that exclusive breastfeeding influences weight development, but it does not seem to protect against obesity at five years of age.

  2. How did it become possible? Supranational Ecumenical developments and changes in Religious Education during the 1960s and 70s’

    Directory of Open Access Journals (Sweden)

    Jonathan Doney

    2015-08-01

    Full Text Available Existing historiographies of Religious Education (RE are often written from within national boundaries, reflecting the particular relationship between church and state within those bounded spaces; further, they often focus on the question ‘what happened?’. During the 1960s significant developments took place in the supranational discourse of Christian ecumenism, including the expansion of dialogue between Christians and those of other worldviews (both religious and non-religious particularly as a result of the Second Vatican Council (1962-5 and the work of the World Council of Churches (established 1948. These supranational ecumenical discourses transcend national boundaries and thus have potential to influence even the most nationally-orientated educational systems. However, their significance has hitherto been overlooked. Using a method derived from the historical work of Michel Foucault, which focuses on the question ‘how did this become possible?’, this paper demonstrates the extent to which an awareness of supranational ecumenical discourses enriches understandings of the development of World Religions Teaching in Religious Education. The English context is used as an exemplar, through a single case study, and the potential of the approach is discussed in relation to other national contexts.

  3. Agricultural population of Belgrade city territory: Basic tendencies in the demographic development, problems and possibilities of its revitalization

    Directory of Open Access Journals (Sweden)

    Jovanović Jasmina

    2006-01-01

    Full Text Available The territory of Belgrade city after the Second World War, has been characterized by the intensive processes of qualitative transformation concerning settling and arrangement of population, territorial organization of production and other activities. The facts that mostly influenced these processes are migrations, caused by economic movements and development. There has been a sudden transfer of agricultural population into non-agricultural activities. Participation of agricultural population in total population of Belgrade city has decreased from 29,7% in 1953 to 12,6% in 1971, and to 2,2% in 2002. Participation of active agricultural population in total active population in Belgrade city has decreased from 34,5% in 1953 to 16,3% in 1971, and to 4,1% in 2002. The decrease of the total and active agricultural population is the result of the weakened influence of demographic factors (changes in number and structure of the total and active population, as well as the greater influence of socio-economic factors. The basic tendencies of the future demographic development of agricultural population are influenced by the possibilities of its revitalization, because demographic reserves to from new working powers in agriculture are endangered.

  4. Mechanistic studies aimed at the development of single site metal alkoxide catalysts for the production of polyoxygenates from renewable resources.

    Energy Technology Data Exchange (ETDEWEB)

    Chisholm, Malcolm H. [The Ohio State Univ., Columbus, OH (United States)

    2015-12-15

    The work proposed herein follows on directly from the existing 3 year grant and the request for funding is for 12 months to allow completion of this work and graduation of current students supported by DOE. The three primary projects are as follows. 1.) A comparative study of the reactivity of LMg(OR) (solvent), where L= a β-diiminate or pyrromethene ligand, in the ring-opening of cyclic esters. 2.) The homopolymerization of expoxides, particularly propylene oxide and styrene oxide, and their copolymerizations with carbon dioxide or organic anhydrides to yield polycarbonates or polyesters, respectively. 3.) The development of well-defined bismuth (III) complexes for ring-opening polymerizations that are tolerant of both air and water. In each of these topics special emphasis is placed on developing a detailed mechanistic understanding of the ring-opening event and how this is modified by the employment of specific metal and ligand combinations. This document also provides a report on findings of the past grant period that are not yet in the public domain/published and shows how the proposed work will bring the original project to conclusion.

  5. Idea of environmental catalyst and its application; Kankyo shokubai no hasso to sono riyo

    Energy Technology Data Exchange (ETDEWEB)

    Inumaru, K. [The University of Tokyo, Tokyo (Japan)

    1997-10-20

    The catalyst creating environmental conservation and comfortable environment is generally named an `environmental catalyst (EC).` EC is roughly classified into direct and indirect type ECs. Purification catalysts for automobile exhaust gas, and catalysts for chemical production process are under investigation as direct and indirect type ECs, respectively. The catalyst was found which can remove NOx under the coexistence of oxygen by using hydrocarbon as reductant. In addition, the practical exhaust gas purification catalyst was also developed for lean-burn engines by combining noble metal catalysts with NOx absorbing materials or zeolite superior in reductant adsorbing power. {epsilon}-caprolactam as raw material of nylon 6 is synthesized from cyclohexanoneoxime through Beckmann` rearrangement reaction. Zeolite system solid catalysts using no ammonia are under investigation. An environment-friendly synthesis method using not phosgene but catalyst was proposed for production of dimethyl carbonate. How to utilize catalysts for global material circulation remains unsolved for the future study. 5 refs.

  6. Analysis of market possibilities for development of pipe-rolling production on PJSC «Sumy Frunze MNPO»

    Directory of Open Access Journals (Sweden)

    S.M. Illiashenko

    2013-03-01

    mills of cold rolling of pipes. The analysis was made with consecutive specification of market prospects ofPJSC Sumy Frunze MNPO. Methods of SWOT-analysis, PEST-analysis and SNW-analysis were used. Features formation of the innovative strategy development of PJSC are defined as result of the analysis. They will allow to get the balance between external and internal possibilities of development and to increase chances of PJSC to reach the success.The main external (of direct and indirect action and internal risk factors of the innovative project of production and modernization of cold-rolling pipes are revealed. The quantitative assessment of extent of their influence is executed with the method of expert evaluations. It is established that at this combination of factors the enterprise is in zone of the increased risk, generally because owing to adverse influence of external factors.The assessment of financial stability of innovative project showed its absolute stability and absence of investment risk, generally because of alleged financing of the project only at the expense of own means of PJSC.The identified multiple-factor quantitative assessment of risk allowed establishing value termsof possible losses (for separate stages and for innovative project as a whole at worst-case scenarios. Comparison of possible losses (taking into account probability of their emergence with the expected income of the project and PJSC as a whole testifies about the acceptable size of risk (even for the pessimistic type of behavior of the person making the decision at implementation of the innovative project of production and modernization of cold-rolling of pipes.Detailed analysis of innovative development potential of PJSC (including the analysis of its separate components: market, innovative, production and marketing potentials concerning production and modernization of pipe-rolling camps which testifies about high chances of implementation of the considered innovative project is made

  7. Catalysts, methods of making catalysts, and methods of use

    KAUST Repository

    Renard, Laetitia

    2014-03-06

    Embodiments of the present disclosure provide for catalysts, methods of making catalysts, methods of using catalysts, and the like. In an embodiment, the method of making the catalysts can be performed in a single step with a metal nanoparticle precursor and a metal oxide precursor, where a separate stabilizing agent is not needed.

  8. Effects of magnolol on UVB-induced skin cancer development in mice and its possible mechanism of action

    Directory of Open Access Journals (Sweden)

    Chilampalli Chandeshwari

    2011-10-01

    Full Text Available Abstract Background Magnolol, a plant lignan isolated from the bark and seed cones of Magnolia officinalis, has been shown to have chemopreventive effects on chemically-induced skin cancer development. The objectives of this investigation are to study the anticarcinogenic effects of magnolol on UVB-induced skin tumor development in SKH-1 mice, a model relevant to humans, and determine the possible role of apoptosis and cell cycle arrest involved in the skin tumor development. Methods UVB-induced skin carcinogenesis model in SKH-1 mice was used for determining the preventive effects of magnolol on skin cancer development. Western blottings and flow cytometric analysis were used to study the effects of magnolol on apoptosis and cell cycle. Results Magnolol pretreated groups (30, 60 μ g before UVB treatments (30 mJ/cm2, 5 days/week resulted in 27-55% reduction in tumor multiplicity as compared to control group in SKH-1 mice. Magnolol pretreatment increased the cleavage of caspase-8 and poly-(-ADP-ribose polymerase (PARP, increased the expression of p21, a cell cycle inhibitor, and decreased the expression of proteins involved in the G2/M phase of cell cycle in skin samples from SKH-1 mice. Treatment of A431 cells with magnolol decreased cell viability and cell proliferation in a concentration dependent manner. Magnolol induced G2/M phase cell cycle arrest in A431 cells at 12 h with a decreased expression of cell cycle proteins such as cyclin B1, cyclin A, CDK4, Cdc2 and simultaneous increase in the expression of Cip/p21, a cyclin-dependent kinase inhibitor. Magnolol induced apoptosis in vivo and in vitro with an increased cleavage of caspase-8 and PARP. Phospho-signal transducers and activators of transcription 3 (Tyr705, B-Raf, p-MEK, and p-AKT were down-regulated, whereas phosphorylation of ERK was induced by magnolol in A431 cells. Conclusions Magnolol pretreatments prevent UVB-induced skin cancer development by enhancing apoptosis, causing

  9. Synthesis and Understanding of Novel Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Stair, Peter C. [Northwestern University

    2013-07-09

    The research took advantage of our capabilities to perform in-situ and operando Raman spectroscopy on complex systems along with our developing expertise in the synthesis of uniform, supported metal oxide materials to investigate relationships between the catalytically active oxide composition, atomic structure, and support and the corresponding chemical and catalytic properties. The project was organized into two efforts: 1) Synthesis of novel catalyst materials by atomic layer deposition (ALD). 2) Spectroscopic and chemical investigations of coke formation and catalyst deactivation. ALD synthesis was combined with conventional physical characterization, Raman spectroscopy, and probe molecule chemisorption to study the effect of supported metal oxide composition and atomic structure on acid-base and catalytic properties. Operando Raman spectroscopy studies of olefin polymerization leading to coke formation and catalyst deactivation clarified the mechanism of coke formation by acid catalysts.

  10. Catalyst in Basic Oleochemicals

    Directory of Open Access Journals (Sweden)

    Eva Suyenty

    2007-10-01

    Full Text Available Currently Indonesia is the world largest palm oil producer with production volume reaching 16 million tones per annum. The high crude oil and ethylene prices in the last 3 – 4 years contribute to the healthy demand growth for basic oleochemicals: fatty acids and fatty alcohols. Oleochemicals are starting to replace crude oil derived products in various applications. As widely practiced in petrochemical industry, catalyst plays a very important role in the production of basic oleochemicals. Catalytic reactions are abound in the production of oleochemicals: Nickel based catalysts are used in the hydrogenation of unsaturated fatty acids; sodium methylate catalyst in the transesterification of triglycerides; sulfonic based polystyrene resin catalyst in esterification of fatty acids; and copper chromite/copper zinc catalyst in the high pressure hydrogenation of methyl esters or fatty acids to produce fatty alcohols. To maintain long catalyst life, it is crucial to ensure the absence of catalyst poisons and inhibitors in the feed. The preparation methods of nickel and copper chromite catalysts are as follows: precipitation, filtration, drying, and calcinations. Sodium methylate is derived from direct reaction of sodium metal and methanol under inert gas. The sulfonic based polystyrene resin is derived from sulfonation of polystyrene crosslinked with di-vinyl-benzene. © 2007 BCREC UNDIP. All rights reserved.[Presented at Symposium and Congress of MKICS 2007, 18-19 April 2007, Semarang, Indonesia][How to Cite: E. Suyenty, H. Sentosa, M. Agustine, S. Anwar, A. Lie, E. Sutanto. (2007. Catalyst in Basic Oleochemicals. Bulletin of Chemical Reaction Engineering and Catalysis, 2 (2-3: 22-31.  doi:10.9767/bcrec.2.2-3.6.22-31][How to Link/DOI: http://dx.doi.org/10.9767/bcrec.2.2-3.6.22-31 || or local: http://ejournal.undip.ac.id/index.php/bcrec/article/view/6

  11. Carbon-based metal-free catalysts

    Science.gov (United States)

    Liu, Xien; Dai, Liming

    2016-11-01

    Metals and metal oxides are widely used as catalysts for materials production, clean energy generation and storage, and many other important industrial processes. However, metal-based catalysts suffer from high cost, low selectivity, poor durability, susceptibility to gas poisoning and have a detrimental environmental impact. In 2009, a new class of catalyst based on earth-abundant carbon materials was discovered as an efficient, low-cost, metal-free alternative to platinum for oxygen reduction in fuel cells. Since then, tremendous progress has been made, and carbon-based metal-free catalysts have been demonstrated to be effective for an increasing number of catalytic processes. This Review provides a critical overview of this rapidly developing field, including the molecular design of efficient carbon-based metal-free catalysts, with special emphasis on heteroatom-doped carbon nanotubes and graphene. We also discuss recent advances in the development of carbon-based metal-free catalysts for clean energy conversion and storage, environmental protection and important industrial production, and outline the key challenges and future opportunities in this exciting field.

  12. ALKALI RESISTANT CATALYST

    DEFF Research Database (Denmark)

    2008-01-01

    The present invention concerns the selective removal of nitrogen oxides (NOx) from gasses. In particular, the invention concerns a process, a catalyst and the use of a catalyst for the selective removal of nitrogen oxides in the presence of ammonia from gases containing a significant amount...... of alkali metal and/or alkali-earth compounds which process comprises using a catalyst combined of (i) a formed porous superacidic support, said superacidic support having an Hammett acidity stronger than Ho=-12, and (ii) a metal oxide catalytic component deposited on said superacidic support selected from...

  13. The possibility to reconcile the conflict between the preservation of synanthropic vegetation and the development of cities

    Directory of Open Access Journals (Sweden)

    Ewa Trzaskowska

    2012-12-01

    Full Text Available The impoverishment of synanthropic vegetation has been observed in Polish cities for at least half a century. It relates to both the decrease in the area of its occurrence and reduction in species diversity. This is associated with changes in land development, a faster construction process, and an increasingly smaller area of wasteland as well as with the fact that agricultural land and farm buildings are found in cities less and less frequently. Municipal management has been modernised and rubbish, soil or rubble dumps are encountered less often. Besides, the aesthetics adopted by modern man does not allow for the existence of spontaneous vegetation, since in an ordered world such great freedom and liberty are not accepted. Nevertheless, synanthropic flora is one of elements of greenery co-creating a unique urban ecosystem. It increases species richness, improves the climate, and contributes to a reduction in pollution and noise. The present paper highlights difficulties related to the preservation of this flora in cities, and a concept is presented how to introduce it into urban green spaces. Different forms of green spaces are presented in the case of which it is possible to use synanthropic plants, e.g.: ecological lawns and flower meadows, extensive roof gardens, and ecological parks.

  14. Immunohistochemical study in dural arteriovenous fistula and possible role of ephrin-B2 for development of dural arteriovenous fistula

    Institute of Scientific and Technical Information of China (English)

    Wuttipong Tirakotai 王宝隆; BIAN Liu-guan 卞留贯; Helmut Bertalanffy; Siegfried Bien; Ulrich Sure

    2004-01-01

    Background Although there were several clinical and experimental studies discussing the pathogenesis of dural arteriovenous fistula (DAVF), the pathological process leading to intracranial DAVF so far remains unknown. In this study, we investigated the expression of vascular growth factors in order to elucidate the possible role of these factors for the development of DAVF and to study the biological activity of this uncommon lesion.Methods We examined the histological features, proliferative and angiogenic capacities of the tissue specimens obtained from 6 patients who underwent surgery at our institution. Immunohistochemical staining for vascular endothelial growth factor (VEGF), its receptors Flk-1 and Flt-1, ephrin-B2, MIB-1 and proliferating cell nuclear antigen (PCNA) was performed using standard immunohistochemical techniques. Results A positive immunostaining was found for all antibodies studied except MIB-1, whereas nuclear endothelial expression of PCNA was observed in only 3/6 cases. VEGF stained positive in all of the available specimens (6/6). Flk-1 showed a positive immunoreaction in only 2/6 cases and Flt-1 in 4/6 cases. Ephrin-B2 was expressed in the majority (5/6) of the cases.Conclusions These results support the hypothesis that DAVFs might be acquired dynamic vascular malformations with low biological activity. Vascular growth factors like VEGF and ephrin-B2 might play a pivotal role in the formation of DAVF.

  15. On the possibility to develop an advanced non-equilibrium model of depressurisation in two-phase fluids

    Science.gov (United States)

    Duc, Linh Do; Horák, Vladimír; Kulish, Vladimir; Lukáč, Tomáš

    2017-01-01

    Carbon dioxide is widely used as the power gas in the gas guns community due to its ease of handling, storability at room temperature, and high vapor pressure depending only upon temperature, but not a tank size, as long as some liquid carbon dioxide remains in the tank. This high vapor pressure can be used as the pressurant, making it what is referred to as a self-pressurising propellant. However, as a two-phase substance, carbon dioxide does have its drawbacks: (1) vaporization of liquefied CO2 inside a tank when shooting rapidly or a lot causes the tank to get cool, resulting in pressure fluctuations that makes the gun's performance and accuracy worse, (2) solid carbon dioxide that is also known as dry ice can appear on the output valve of the tank while shooting and it can cause damage or slow the gun's performance down, if it works its way into some control components, including the barrel of the gun. Hence, it is crucial to obtain a scientific understanding of carbon dioxide behavior and further the discharge characteristics of a wide range of pressure-tank configurations. For the purpose of satisfying this goal, a comprehensive discharge mathematical model for carbon dioxide tank dynamics is required. In this paper, the possibility to develop an advanced non-equilibrium model of depressurization in two-phase fluids is discussed.

  16. Fish consumption and its possible preventive role on the development and prevalence of metabolic syndrome - a systematic review.

    Science.gov (United States)

    Tørris, Christine; Molin, Marianne; Cvancarova Småstuen, Milada

    2014-01-01

    Metabolic syndrome (MetS) has a huge impact on public health, and today lifestyle interventions remain the primary mode for MetS therapy. It is therefore important to elucidate the possible preventive effects of diet and foods, and their MetS-related health implications. To examine how fish consumption affects the development and prevalence of MetS, we systematically reviewed cross-sectional, prospective cohort, and intervention studies conducted among adults (humans) and, reporting consumption of fish or seafood as being related to MetS (prevalence or incidence), where MetS was defined via an established definition. The literature search in PubMed identified 502 citations, and after screening, 49 full-text articles were retrieved and assessed for eligibility. After excluding duplicates and those not meeting the inclusion criteria, seven studies from Croatia, Finland, France, Iceland, Iran, Korea, and US were included. Four studies (one follow-up and three cross-sectional) found associations between fish consumption and MetS (three among men, and one among women), suggesting that fish consumption may prevent or improve metabolic health and have a protective role in MetS prevention. This protective role might be related to gender, and men may benefit more from the consumption of fish. However, lack of controlling for potential confounders may also inflict the results. Additional research is required to further explore fish consumption and its potential role in improving or reversing MetS and its components.

  17. Biodiesel production using heterogeneous catalysts.

    Science.gov (United States)

    Semwal, Surbhi; Arora, Ajay K; Badoni, Rajendra P; Tuli, Deepak K

    2011-02-01

    The production and use of biodiesel has seen a quantum jump in the recent past due to benefits associated with its ability to mitigate greenhouse gas (GHG). There are large number of commercial plants producing biodiesel by transesterification of vegetable oils and fats based on base catalyzed (caustic) homogeneous transesterification of oils. However, homogeneous process needs steps of glycerol separation, washings, very stringent and extremely low limits of Na, K, glycerides and moisture limits in biodiesel. Heterogeneous catalyzed production of biodiesel has emerged as a preferred route as it is environmentally benign needs no water washing and product separation is much easier. The present report is review of the progress made in development of heterogeneous catalysts suitable for biodiesel production. This review shall help in selection of suitable catalysts and the optimum conditions for biodiesel production.

  18. Catalyst for microelectromechanical systems microreactors

    Science.gov (United States)

    Morse, Jeffrey D.; Sopchak, David A.; Upadhye, Ravindra S.; Reynolds, John G.; Satcher, Joseph H.; Gash, Alex E.

    2010-06-29

    A microreactor comprising a silicon wafer, a multiplicity of microchannels in the silicon wafer, and a catalyst coating the microchannels. In one embodiment the catalyst coating the microchannels comprises a nanostructured material. In another embodiment the catalyst coating the microchannels comprises an aerogel. In another embodiment the catalyst coating the microchannels comprises a solgel. In another embodiment the catalyst coating the microchannels comprises carbon nanotubes.

  19. Epoxidation catalyst and process

    Science.gov (United States)

    Linic, Suljo; Christopher, Phillip

    2010-10-26

    Disclosed herein is a catalytic method of converting alkenes to epoxides. This method generally includes reacting alkenes with oxygen in the presence of a specific silver catalyst under conditions suitable to produce a yield of the epoxides. The specific silver catalyst is a silver nanocrystal having a plurality of surface planes, a substantial portion of which is defined by Miller indices of (100). The reaction is performed by charging a suitable reactor with this silver catalyst and then feeding the reactants to the reactor under conditions to carry out the reaction. The reaction may be performed in batch, or as a continuous process that employs a recycle of any unreacted alkenes. The specific silver catalyst has unexpectedly high selectivity for epoxide products. Consequently, this general method (and its various embodiments) will result in extraordinarily high epoxide yields heretofore unattainable.

  20. New Catalysts for ROMP

    Institute of Scientific and Technical Information of China (English)

    H. Berke; C. Frech; A. Lhamazares; O. Blacque; H.W. Schmalle; C. Adlhart; P. Chen

    2005-01-01

    @@ 1Introduction Ring Opening Metathesis Polymerization (ROMP) is based on the olefin metathesis reaction, which requires transition metal catalysts. Mainly molybdenum, tungsten and ruthenium based catalysts have up to now been used. The "in-between" metal rhenium was only rarely applied in olefin metathesis reactions, and not at all in ROMP processes.We have found that cationic phosphine substituted dinitrosyl rhenium complexes[1]1a and 1b effectively catalyze ROMP of norbonene, dicyclopentadiene and of cyclooctene. See Fig. 1.

  1. Expression of glyoxalase-I is reduced in cirrhotic livers: A possible mechanism in the development of cirrhosis

    Science.gov (United States)

    Hollenbach, Marcus; Thonig, Antje; Pohl, Sabine; Ripoll, Cristina; Michel, Maurice; Zipprich, Alexander

    2017-01-01

    Background High concentrations of methylglyoxal (MGO) cause cytotoxiticy via formation of advanced glycation endproducts (AGEs) and inflammation. MGO is detoxificated enzymatically by glyoxalase-I (Glo-I). The aim of this study was to analyze the role of Glo-I during the development of cirrhosis. Methods In primary hepatocytes, hepatic stellate cells (pHSC) and sinusoidal endothelial cells (pLSEC) from rats with early (CCl4 8wk) and advanced cirrhosis (CCl4 12wk) expression and activity of Glo-I were determined and compared to control. LPS stimulation (24h; 100ng/ml) of HSC was conducted in absence or presence of the partial Glo-I inhibitor ethyl pyruvate (EP) and the specific Glo-I inhibitor BrBzGSHCp2. MGO, inflammatory and fibrotic markers were measured by ELISA and Western blot. Additional rats were treated with CCl4 ± EP 40mg/kg b.w. i.p. from wk 8–12 and analyzed with sirius red staining and Western blot. Results Expression of Glo-I was significantly reduced in cirrhosis in whole liver and primary liver cells accompanied by elevated levels of MGO. Activity of Glo-I was reduced in cirrhotic pHSC and pLSEC. LPS induced increases of TNF-α, Nrf2, collagen-I, α-SMA, NF-kB and pERK of HSC were blunted by EP and BrBzGSHCp2. Treatment with EP during development of cirrhosis significantly decreased the amount of fibrosis (12wk CCl4: 33.3±7.3%; EP wk 8–12: 20.7±6.2%; p<0.001) as well as levels of α-SMA, TGF-β and NF-κB in vivo. Conclusions Our results show the importance of Glo-I as major detoxifying enzyme for MGO in cirrhosis. The reduced expression of Glo-I in cirrhosis demonstrates a possible explanation for increased inflammatory injury and suggests a “vicious circle” in liver disease. Blunting of the Glo-I activity decrease the amount of fibrosis in established cirrhosis and constitutes a novel target for antifibrotic therapy. PMID:28231326

  2. Exploration of Nanotube Structure Selectivity Using Bimetallic Catalysts

    Science.gov (United States)

    Pfefferle, Lisa

    2007-10-01

    Achieving selectivity for nanotube chirality is one of the holy grails for single-walled carbon nanotube research. One approach we are following is based on the ability to engineer the size and state of the initiating metal particle to constrain the type of cap formed. The chirality/structure of a nanotube is controlled by carbon cap formation on the metal particle during the nucleation step. It has been proposed that varying the carbon-metal catalyst binding energy could help lead to structure selectivity. One reason theoretically proposed for the favoring of armchair nanotubes, for example, is the proximity of low energy binding locations for two carbon atoms. Thus blocking sites or perturbing the binding energy on adjacent sites could in theory affect the structure of the carbon cap formed in the nucleation step. Our goal is to demonstrate structure selectivity in the growth of single wall carbon nanotubes (SWNT) using a bimetallic catalyst. The catalyst used was a bimetallic CoCr-MCM 41 and the effect of different molecular ratios between the two metals on the SWNT diameter distribution was studied. We have found that by adding Cr to the Co-MCM 41 monometallic catalyst the diameter distribution shifted in a systematic manner correlated to the development of a bimetallic phase as characterized by X-Ray absorption spectroscopy (XAS). We have also found that the shift is accompanied by suppression of metallic SWNT, particularly those with diameter over 0.9 nm. We are also currently exploring the possibility of a further narrowing of the distribution by lowering the reaction temperatures.

  3. INVESTIGATION OF MIXED METAL SORBENT/CATALYSTS FOR THE SIMULTANEOUS REMOVAL OF SULFUR AND NITROGEN OXIDES

    Energy Technology Data Exchange (ETDEWEB)

    Ates Akyurtlu; Jale F. Akyurtle

    2001-08-01

    Simultaneous removal of SO{sub 2} and NO{sub x} using a regenerable solid sorbent will constitute an important improvement over the use of separate processes for the removal of these two pollutants from stack gases and possibly eliminate several shortcomings of the individual SO{sub 2} and NO{sub x} removal operations. The work done at PETC and the DOE-funded investigation of the investigators on the sulfation and regeneration of alumina-supported cerium oxide sorbents have shown that they can perform well at relatively high temperatures (823-900 K) as regenerable desulfurization sorbents. Survey of the recent literature shows that addition of copper oxide to ceria lowers the sulfation temperature of ceria down to 773 K, sulfated ceria-based sorbents can function as selective SCR catalysts even at elevated temperatures, SO{sub 2} can be directly reduced to sulfur by CO on CuO-ceria catalysts, and ceria-based catalysts may have a potential for selective catalytic reduction of NO{sub x} by methane. These observations indicate a possibility of developing a ceria-based sorbent/catalyst which can remove both SO{sub 2} and NO{sub x} from flue gases within a relatively wide temperature window, produce significant amounts of elemental sulfur during regeneration, and use methane for the selective catalytic reduction of NO{sub x}.

  4. Persistent Possible Science Selves

    Science.gov (United States)

    Mills, Leila A.; Lin, Lin

    2014-01-01

    This paper examines literature on the development of self-knowledge for possible selves--how an individual thinks about oneself and one's potential future selves (Markus & Nurius, 1986). Future science selves research, a recent offshoot of possible selves theories, centers on the development and loss of future possible scientific selves and…

  5. Optimization of fuel cell membrane electrode assemblies for transition metal ion-chelating ordered mesoporous carbon cathode catalysts

    OpenAIRE

    Johanna K. Dombrovskis; Cathrin Prestel; Anders E. C. Palmqvist

    2014-01-01

    Transition metal ion-chelating ordered mesoporous carbon (TM-OMC) materials were recently shown to be efficient polymer electrolyte membrane fuel cell (PEMFC) catalysts. The structure and properties of these catalysts are largely different from conventional catalyst materials, thus rendering membrane electrode assembly (MEA) preparation parameters developed for conventional catalysts not useful for applications of TM-OMC catalysts. This necessitates development of a methodology to incorporate...

  6. Optimization of fuel cell membrane electrode assemblies for transition metal ion-chelating ordered mesoporous carbon cathode catalysts

    Directory of Open Access Journals (Sweden)

    Johanna K. Dombrovskis

    2014-12-01

    Full Text Available Transition metal ion-chelating ordered mesoporous carbon (TM-OMC materials were recently shown to be efficient polymer electrolyte membrane fuel cell (PEMFC catalysts. The structure and properties of these catalysts are largely different from conventional catalyst materials, thus rendering membrane electrode assembly (MEA preparation parameters developed for conventional catalysts not useful for applications of TM-OMC catalysts. This necessitates development of a methodology to incorporate TM-OMC catalysts in the MEA. Here, an efficient method for MEA preparation using TM-OMC catalyst materials for PEMFC is developed including effects of catalyst/ionomer loading and catalyst/ionomer-mixing and application procedures. An optimized protocol for MEA preparation using TM-OMC catalysts is described.

  7. A One-Bead-One-Catalyst Approach to Aspartic Acid-Based Oxidation Catalyst Discovery

    Science.gov (United States)

    Lichtor, Phillip A.; Miller, Scott J.

    2011-01-01

    We report an approach to the high-throughput screening of asymmetric oxidation catalysts. The strategy is based on application of the one-bead-one-compound library approach, wherein each of our catalyst candidates is based on a peptide scaffold. For this purpose we rely on a recently developed catalytic cycle that employs an acid-peracid shuttle. In order to implement our approach, we developed a compatible linker and demonstrated that the library format is amenable to screening and sequencing of catalysts employing partial Edman degradation and MALDI mass spectrometry analysis. The system was applied to the discovery (and re-discovery) of catalysts for the enantioselective oxidation of a cyclohexene derivative. The system is now poised for application to unprecedented substrate classes for asymmetric oxidation reactions. PMID:21417485

  8. Improving Stability of Gasoline by Using Ionic Liquid Catalyst

    Institute of Scientific and Technical Information of China (English)

    Gao Zhirong; Liu Daosheng; Liao Kejian; Jian Heng

    2003-01-01

    The composition, characteristics and preparation of ionic liquids are presented. The factors influencing the stability of gasoline and the significance of improving gasoline stability are discussed. A novel way to improve the stability of gasoline by using ionic liquid catalyst is developed. The contents of olefin, basic nitrogen and sulfur in gasoline are determined and the optimal experimental conditions for improving gasoline stability are established.The ionic liquid catalyst, which is environmentally friendly, can reduce the olefin content in gasoline, and such process is noted for mild reaction conditions, simple operation, short reaction time, easy recycling of the ionic liquid catalyst and ready separation of products and catalyst.

  9. First Commercial Application of Upflow Residuum Hydrotreating Catalyst

    Institute of Scientific and Technical Information of China (English)

    Mu Haitao; Sun Zhenguang

    2004-01-01

    This article refers to the first commercial application of upflow residuum hydrotreating serial catalyst, developed by Fushun Research Institute of Petroleum and Petrochemicals (FRIPP), in the residuum hydrotreating unit at Shengli refinery of Qilu Petrochemical Company. This catalyst features large pore volume and large pore diameter. The production practice for more than one year has revealed that the domestic upflow residuum hydrotreating catalyst has shown good performance and stability over the whole period of operation despite its high activity at the start of run, and has basically reached the level of similar imported catalyst.

  10. Selective Oxidations using Nanostructured Heterogeneous Catalysts

    DEFF Research Database (Denmark)

    Mielby, Jerrik Jørgen

    and because they produce H2O as the only by-product. Chapter 1 gives a short introduction to basic concepts in heterogeneous catalysis and green chemistry. Furthermore, the chapter gives an overview of the most important strategies to synthesise functional nanostructured materials and highlights how detailed......The aim of this thesis is to investigate and develop new efficient methods to oxidise alcohols and amines using heterogeneous catalysts and either O2 or H2O2 as oxidants. From an economic and environmental point of view, these oxidants are ideal, because they are cheap and readily available...... understanding of size, shape and structure can help in the development of new and more efficient heterogeneous catalysts. The chapter is not intended to give a complete survey, but rather to introduce some of the recent developments in the synthesis of nanostructured heterogeneous catalysts. Finally...

  11. Walkable new urban LEED_Neighborhood-Development (LEED-ND community design and children's physical activity: selection, environmental, or catalyst effects?

    Directory of Open Access Journals (Sweden)

    Stevens, Robert B

    2011-12-01

    Full Text Available Abstract Background Interest is growing in physical activity-friendly community designs, but few tests exist of communities explicitly designed to be walkable. We test whether students living in a new urbanist community that is also a pilot LEED_ND (Leadership in Energy and Environmental Design-Neighborhood Development community have greater accelerometer-measured moderate-to-vigorous physical activity (MVPA across particular time periods compared to students from other communities. We test various time/place periods to see if the data best conform to one of three explanations for MVPA. Environmental effects suggest that MVPA occurs when individuals are exposed to activity-friendly settings; selection effects suggest that walkable community residents prefer MVPA, which leads to both their choice of a walkable community and their high levels of MVPA; catalyst effects occur when walking to school creates more MVPA, beyond the school commute, on schooldays but not weekends. Methods Fifth graders (n = 187 were sampled from two schools representing three communities: (1 a walkable community, Daybreak, designed with new urbanist and LEED-ND pilot design standards; (2 a mixed community (where students lived in a less walkable community but attended the walkable school so that part of the route to school was walkable, and (3 a less walkable community. Selection threats were addressed through controlling for parental preferences for their child to walk to school as well as comparing in-school MVPA for the walkable and mixed groups. Results Minutes of MVPA were tested with 3 × 2 (Community by Gender analyses of covariance (ANCOVAs. Community walkability related to more MVPA during the half hour before and after school and, among boys only, more MVPA after school. Boys were more active than girls, except during the half hour after school. Students from the mixed and walkable communities--who attended the same school--had similar in-school MVPA levels, and

  12. New catalysts for exhaust gas cleaning

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, M. [Kemira Metalkat Oy, Oulu (Finland)

    1996-12-31

    Major challenge for future catalyst systems was to develop thermally more stable washcoats for close coupled operating conditions and for engines operating under high speed and load conditions. To design these future emission systems extensive research and development was undertaken to develop methods to disperse and stabilize the key catalytic materials for operation at much higher temperatures. Second priority was to design catalysts that are more effective under low temperature exhaust conditions and have improved oxygen storage properties in the washcoats. Incorporating new materials and modified preparation technology a new generation of metallic catalyst formulations emerged, those being trimetallic K6 (Pt:Pd:Rh and bimetallic K7) (Pd+Pd:Rh). The target was to combine the best property of Pt:Rh (good NO{sub x} reduction) with that of the good HC oxidation activity of Pd and to ensure that precious metal/support interactions were positively maintained. Both K6 and K7 concepts contain special catalyst structures with optimized washcoat performance which can be brick converter configuration. Improvement in light-off, thermal stability and transient performance with these new catalyst formulations have clearly been shown in both laboratory and vehicle testing. (author) (20 refs.)

  13. Development of robust Co-based catalysts for the selective H{sub 2}-production by ethanol steam-reforming. The Fe-promoter effect

    Energy Technology Data Exchange (ETDEWEB)

    De la Pena O' Shea, Victor A.; Nafria, Raquel; Ramirez de la Piscina, Pilar; Homs, Narcis [Departament de Quimica Inorganica, Institut de Nanociencia i Nanotecnologia, Universitat de Barcelona, Marti i Franques 1-11, 08028 Barcelona (Spain)

    2008-07-15

    The effect of iron promoter on cobalt-based catalysts, active in the ethanol steam-reforming, was studied. Fe{sub x}Co{sub 3-x}O{sub 4}(0{<=} x{<=}0.60) oxides prepared by co-precipitation and an Fe-doped Co{sub 3}O{sub 4} prepared by wetness impregnation are analysed. The activation process of the oxides under reaction conditions was studied by in situ X-ray diffraction (XRD); the activation depended on the iron content of the oxides. The systems were characterized by means of temperature programmed reduction (TPR), XRD and tested in the ethanol steam-reforming reaction at 623-673 K. An optimal iron loading that gives rise to a high H{sub 2}selectivity and catalyst stability was determined. (author)

  14. Development of Fe-Ni/YSZ-GDC electro-catalysts for application as SOFC anodes. XRD and TPR characterization, and evaluation in ethanol steam reforming reaction

    Energy Technology Data Exchange (ETDEWEB)

    Paz Fiuza, Raigenis da; Silva, Marcos Aurelio da; Boaventura, Jaime Soares [UFBA, Salvador, Bahia (Brazil). Energy and Materials Science Group

    2010-07-01

    Electro-catalysts based on Fe-Ni alloys were prepared using physical mixture and modified Pechini methods; they were supported on a composite of Yttria Stabilized Zirconia (YSZ) and Gadolinia Doped Ceria (GDC). The composites had compositions of 35% metal load and 65% support (70% wt. YSZ and 30% wt. GDC mixture) (cermets). The samples were characterized by Temperature-Programmed Reduction (TPR) and X-Ray Diffraction (XRD) and evaluated in ethanol steam reforming at 650 C for six hours and in the temperature range 300 - 900 C. The XRD results showed that the bimetallic sample calcined at 800 C formed a mixed oxide (NiFe{sub 2}O{sub 4}) in spinel structure; after reducing the sample in hydrogen, Ni-Fe alloys were formed. The presence of Ni decreased the final reduction temperature of the NiFe{sub 2}O{sub 4} species. The addition of Fe to Ni anchored to YSZ-GDC increased the hydrogen production and inhibits the carbon deposition. The bimetallic 30Fe5Ni samples reached an ethanol conversion of about 95%, and a hydrogen yield up to 48% at 750 C. In general, the ethanol conversion and hydrogen production were independent of the metal content in the electro-catalyst. However, the substitution of Ni for Fe significantly reduced the carbon deposition on the electro-catalyst: 74, 31 and 9 wt. % in the 35Ni, 20Fe15Ni, and 30Fe5Ni samples, respectively. (orig.)

  15. Collaboration between primitive cell membranes and soluble catalysts.

    Science.gov (United States)

    Adamala, Katarzyna P; Engelhart, Aaron E; Szostak, Jack W

    2016-03-21

    One widely held model of early life suggests primitive cells consisted of simple RNA-based catalysts within lipid compartments. One possible selective advantage conferred by an encapsulated catalyst is stabilization of the compartment, resulting from catalyst-promoted synthesis of key membrane components. Here we show model protocell vesicles containing an encapsulated enzyme that promotes the synthesis of simple fatty acid derivatives become stabilized to Mg(2+), which is required for ribozyme activity and RNA synthesis. Thus, protocells capable of such catalytic transformations would have enjoyed a selective advantage over other protocells in high Mg(2+) environments. The synthetic transformation requires both the catalyst and vesicles that solubilize the water-insoluble precursor lipid. We suggest that similar modified lipids could have played a key role in early life, and that primitive lipid membranes and encapsulated catalysts, such as ribozymes, may have acted in conjunction with each other, enabling otherwise-impossible chemical transformations within primordial cells.

  16. Final Report - Durable Catalysts for Fuel Cell Protection during Transient Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Atanasoski, Radoslav [3M Company, St. Paul, MN (United States); van der Vliet, Dennis [3M Company, St. Paul, MN (United States); Cullen, David [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Atanasoska, Ljiljana [3M Company, St. Paul, MN (United States)

    2015-01-26

    The objective of this project was to develop catalysts that will enable proton exchange membranes (PEM) fuel cell systems to weather the damaging conditions in the fuel cell at voltages beyond the thermodynamic stability of water during the transient periods of start-up/shut-down and fuel starvation. Such catalysts are required to make it possible for the fuel cell to satisfy the 2015 DOE targets for performance and durability. The project addressed a key issue of importance for successful transition of PEM fuel cell technology from development to pre-commercial phase. This issue is the failure of the catalyst and the other thermodynamically unstable membrane electrode assembly (MEA) components during start-up/shut-down and local fuel starvation at the anode, commonly referred to as transient conditions. During these periods the electrodes can reach potentials higher than the usual 1.23V upper limit during normal operation. The most logical way to minimize the damage from such transient events is to minimize the potential seen by the electrodes. At lower positive potentials, increased stability of the catalysts themselves and reduced degradation of the other MEA components is expected.

  17. Supported organoiridium catalysts for alkane dehydrogenation

    Science.gov (United States)

    Baker, R. Thomas; Sattelberger, Alfred P.; Li, Hongbo

    2013-09-03

    Solid supported organoiridium catalysts, a process for preparing such solid supported organoiridium catalysts, and the use of such solid supported organoiridium catalysts in dehydrogenation reactions of alkanes is provided. The catalysts can be easily recovered and recycled.

  18. Ruthenium–Platinum Catalysts and Direct Methanol Fuel Cells (DMFC: A Review of Theoretical and Experimental Breakthroughs

    Directory of Open Access Journals (Sweden)

    Ana S. Moura

    2017-02-01

    Full Text Available The increasing miniaturization of devices creates the need for adequate power sources and direct methanol fuel cells (DMFC are a strong option in the various possibilities under current development. DMFC catalysts are mostly based on platinum, for its outperformance in three key areas (activity, selectivity and stability within methanol oxidation framework. However, platinum poisoning with products of methanol oxidation led to the use of alloys. Ruthenium–platinum alloys are preferred catalysts active phases for methanol oxidation from an industrial point of view and, indeed, ruthenium itself is a viable catalyst for this reaction. In addition, the route of methanol decomposition is crucial in the goal of producing H2 from water reaction with methanol. However, the reaction pathway remains elusive and new approaches, namely in computational methods, have been ensued to determine it. This article reviews the various recent theoretical approaches for determining the pathway of methanol decomposition, and systematizes their validation with experimental data, within methodological context.

  19. Supported organometallic catalysts for hydrogenation and Olefin Polymerization

    Science.gov (United States)

    Marks, Tobin J.; Ahn, Hongsang

    2001-01-01

    Novel heterogeneous catalysts for the which hydrogenation of olefins and arenes with high conversion rates under ambient conditions and the polymerization of olefins have been developed. The catalysts are synthesized from Ziegler-type precatalysts by supporting them on sulfate-modified zirconia.

  20. Nanoscale intimacy in bifunctional catalysts for selective conversion of hydrocarbons

    NARCIS (Netherlands)

    Zecevic, Jovana; Vanbutsele, Gina; de Jong, Krijn P.; Martens, Johan A.

    2015-01-01

    The ability to control nanoscale features precisely is increasingly being exploited to develop and improve monofunctional catalysts(1-4). Striking effects might also be expected in the case of bifunctional catalysts, which are important in the hydrocracking of fossil and renewable hydrocarbon source

  1. NOVEL SLURRY PHASE DIESEL CATALYSTS FOR COAL-DERIVED SYNGAS

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Dragomir B. Bukur; Dr. Ketil Hanssen; Alec Klinghoffer; Dr. Lech Nowicki; Patricia O' Dowd; Dr. Hien Pham; Jian Xu

    2001-01-07

    This report describes research conducted to support the DOE program in novel slurry phase catalysts for converting coal-derived synthesis gas to diesel fuels. The primary objective of this research program is to develop attrition resistant catalysts that exhibit high activities for conversion of coal-derived syngas.

  2. CHARACTERISTICS OF RURAL AREAS IN SLOVENIA: ADVANTAGES, WEAKNESSES AND POSSIBILITIES FOR IMPROVEMENT OF PRESENT SITUATION FROM VIEWPOINT OF SUSTAINABLE RURAL DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Anton Perpar

    2001-09-01

    Full Text Available In the article an analysis of the situation in the Slovene Rural Areas are presented. The comparative analysis, based on typology of rural areas in Slovenia made by The Institute of Agricultural Economics on Biotechnical Faculty, shows that the Slovene countryside is not homogeneous. Present situation and the possibilities of development and the attraction of individual rural areas depend on the demographic situation, on the level of economic and social development, on natural conditions etc. Present situation is analysed from the viewpoint of sustainable rural development: advantages, weaknesses and some possibilities for improvement are presented.

  3. Nanostructural and Chemical Characterization of Supported Metal Oxide Catalysts by Aberration Corrected Analytical Electron Microscopy

    Science.gov (United States)

    Zhou, Wu

    Ox with WOx. As a consequence, the catalytic activity of the co-impregnated material is dramatically increased by more than two orders of magnitude. We further showed in Chapter 5 that the Keggin structure based on phosphotungstic acid hydrate (i.e. an ˜ 1nm P-WOx mixed oxide cluster) can be successfully immobilized on an amorphous SiO2 support surface. Such catalyst design experiments further support our postulated structure-activity model, in which WO x clusters mixed with some low valence heteroatoms are the most active entities for the methanol dehydration and n-pentane isomerization reactions. Another major theme of this thesis is the analysis of model double-supported metal oxide catalysts, in which a high surface area oxide support material (amorphous SiO2) is modified by the presence of a second metal oxide surface species (TiO2 or ZrO2) added to control the distribution and activity of the active surface WOx component. These complex double-supported metal oxide catalysts represent a very significant challenge in terms of structural characterization. A new electron microscopy characterization strategy was developed for this purpose which combined aberration corrected STEM imaging with concurrent EELS and XEDS analysis. We demonstrated that the various components in a double-supported WO3/TiO 2/SiO2 catalyst system can be effectively visualized using complementary HAADF and STEM-BF imaging within an aberration corrected STEM. Furthermore, when combined with chemical analysis by STEM-EELS and XEDS within the same STEM instrument, it is possible to map out the relative spatial distribution of all the metal oxide components within the WO3/TiO2/SiO 2 catalyst. By comparing the structures of a systematic set of WO 3/TiO2/SiO2 samples displaying high, intermediate and low activity for the methanol dehydration reaction, we showed that the acidic catalytic activity seems to benefit from having (i) a more localized electron density on the TiOx support and (ii) a larger WOx

  4. Thermodynamic Properties of Supported Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Gorte, Raymond J.

    2014-03-26

    The goals of this work were to develop Coulometric Titration as a method for characterizing the thermodynamic redox properties of oxides and to apply this technique to the characterization of ceria- and vanadia-based catalysts. The redox properties of ceria and vanadia are a major part of what makes these materials catalytically active but their properties are also dependent on their structure and the presence of other oxides. Quantifying these properties through the measurement of oxidation energetics was the goal of this work.

  5. Conceivability & Possibility

    DEFF Research Database (Denmark)

    2009-01-01

    Conceivability & Possibility – The Prospects of a Reductive Account of Modality er et speciale skrevet af Asger Steffensen, Århus Universitet, 2009. Specialet handler om tænkelighed og mulighed og om udsigterne for en reduktiv teori om modalitet. Med andre ord er specialet et forsøg på at vise, a...

  6. Discovery of Novel NOx Catalysts for CIDI Applications by High-throughput Methods

    Energy Technology Data Exchange (ETDEWEB)

    Blint, Richard J. [General Motors Corporation, Warren, MI (United States)

    2007-12-31

    DOE project DE-PS26-00NT40758 has developed very active, lean exhaust, NOx reduction catalysts that have been tested on the discovery system, laboratory reactors and engine dynamometer systems. The goal of this project is the development of effective, affordable NOx reduction catalysts for lean combustion engines in the US light duty vehicle market which can meet Tier II emission standards with hydrocarbons based reductants for reducing NOx. General Motors (prime contractor) along with subcontractors BASF (Engelhard) (a catalytic converter developer) and ACCELRYS (an informatics supplier) carried out this project which began in August of 2002. BASF (Engelhard) has run over 16,000 tests of 6100 possible catalytic materials on a high throughput discovery system suitable for automotive catalytic materials. Accelrys developed a new database informatics system which allowed material tracking and data mining. A program catalyst was identified and evaluated at all levels of the program. Dynamometer evaluations of the program catalyst both with and without additives show 92% NOx conversions on the HWFET, 76% on the US06, 60% on the cold FTP and 65% on the Set 13 heavy duty test using diesel fuel. Conversions of over 92% on the heavy duty FTP using ethanol as a second fluid reductant have been measured. These can be competitive with both of the alternative lean NOx reduction technologies presently in the market. Conversions of about 80% were measured on the EUDC for lean gasoline applications without using active dosing to adjust the C:N ratio for optimum NOx reduction at all points in the certification cycle. A feasibility analysis has been completed and demonstrates the advantages and disadvantages of the technology using these materials compared with other potential technologies. The teaming agreements among the partners contain no obstacles to commercialization of new technologies to any potential catalyst customers.

  7. MicroChannel Reactors for ISRU Applications Using Nanofabricated Catalysts

    Science.gov (United States)

    Carranza, Susana; Makel, Darby B.; Vander Wal, Randall L.; Berger, Gordon M.; Pushkarev, Vladimir V.

    2006-01-01

    With the new direction of NASA to emphasize the exploration of the Moon, Mars and beyond, quick development and demonstration of efficient systems for In-Situ Resources Utilization (ISRU) is more critical and timely than ever before. Affordable planning and execution of prolonged manned space missions depend upon the utilization of local resources and the waste products which are formed in manned spacecraft and surface bases. This paper presents current development of miniaturized chemical processing systems that combine microchannel reactor design with nanofabricated catalysts. Carbon nanotubes (CNT) are used to produce a nanostructure within microchannel reactors, as support for catalysts. By virtue of their nanoscale dimensions, nanotubes geometrically restrict the catalyst particle size that can be supported upon the tube walls. By confining catalyst particles to sizes smaller than the CNT diameter, a more uniform catalyst particle size distribution may be maintained. The high dispersion permitted by the vast surface area of the nanoscale material serves to retain the integrity of the catalyst by reducing sintering or coalescence. Additionally, catalytic efficiency increases with decreasing catalyst particle size (reflecting higher surface area per unit mass) while chemical reactivity frequently is enhanced at the nanoscale. Particularly significant is the catalyst exposure. Rather than being confined within a porous material or deposited upon a 2-d surface, the catalyst is fully exposed to the reactant gases by virtue of the nanofabricated support structure. The combination of microchannel technology with nanofabricated catalysts provides a synergistic effect, enhancing both technologies with the potential to produce much more efficient systems than either technology alone. The development of highly efficient microchannel reactors will be applicable to multiple ISRU programs. By selection of proper nanofabricated catalysts, the microchannel reactors can be

  8. Ecotourism development in Romania - a possible contribution to the fulfilment of the real convergence criteria for Euro adoption

    Directory of Open Access Journals (Sweden)

    A.- N. Candrea

    2013-06-01

    Full Text Available Ecotourism is a chance to diversify the Romanian tourism industry while protecting the environment and benefiting local communities. The present paper focuses on ecotourism as a possible contribution the fulfilment of the real convergence criteria for euro adoption in Romania by stimulating the economic growth of rural communities. The main benefits that ecotourism brings to rural communities are highlighted as well as the main initiatives of national organisations aimed at stimulating the local economy in different ecotourism destinations.

  9. A HYDROGEN BONDING ASSISTED CATALYST SCREENED OUT VIA COMBINATORIAL CHEMISTRY STRATEGY

    Institute of Scientific and Technical Information of China (English)

    XUMancai; OUZhize; 等

    2000-01-01

    Possibilities for enhancement of catalytic reaction rate by combining phase transfer catalysis and hydrogen bonding of the catalyst with the substrate and reagent were studied.A phase transfer catalyst library with sixty polystyrene-supported quaternary ammonium salt catalysts was synthesized.The reduction of acetophenone by NaBH4 was used as the probing reaction to select out the ost active catalyst in the library by using iterative method.which was the gel-type triethanolamine aminsating strongly asic anion exchange resin with the crosslinking degeree of 2% A hydrogen bonding assisted catalytic mechanism was proposed to explain the high catalytic activity of the catalyst.

  10. Effect of La on Partial Oxidation of Ethanol to Hydrogen over Ni/Fe Catalysts

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The partial oxidation of ethanol to hydrogen was investigated over Ni/Fe/La catalysts prepared by the co-precipitation method. The effects of introduction of La promoter and the reaction temperature on the catalytic performance were studied. It was found that the introduction of La into Ni/Fe catalysts is helpful to increase the selectivity to hydrogen and the stability of the catalysts. The results of XRD and XPS characterization show that the structure of the catalyst was changed during the reaction. The existence of LaFeO3 species is possibly the main reason of the increase of the catalyst stability.

  11. Long term time variability of cosmic rays and possible relevance to the development of life on Earth

    CERN Document Server

    Erlykin, A D

    2010-01-01

    An analysis is made of the manner in which the cosmic ray intensity at Earth has varied over its existence and its possible relevance to both the origin and the evolution of life. Much of the analysis relates to the 'high energy' cosmic rays ($E>10^{14}eV;=0.1PeV$) and their variability due to the changing proximity of the solar system to supernova remnants which are generally believed to be responsible for most cosmic rays up to PeV energies. It is pointed out that, on a statistical basis, there will have been considerable variations in the likely 100 My between the Earth's biosphere reaching reasonable stability and the onset of very elementary life. Interestingly, there is the increasingly strong possibility that PeV cosmic rays are responsible for the initiation of terrestrial lightning strokes and the possibility arises of considerable increases in the frequency of lightnings and thereby the formation of some of the complex molecules which are the 'building blocks of life'. Attention is also given to the...

  12. New Trends in Gold Catalysts

    Directory of Open Access Journals (Sweden)

    Leonarda F. Liotta

    2014-07-01

    Full Text Available Gold is an element that has fascinated mankind for millennia. The catalytic properties of gold have been a source of debate, due to its complete chemical inertness when in a bulk form, while it can oxidize CO at temperatures as low as ~200 K when in a nanocrystalline state, as discovered by Haruta in the late 1980s [1]. Since then, extensive activity in both applied and fundamental research on gold has been initiated. The importance of the catalysis by gold represents one of the fasted growing fields in science and is proven by the promising applications in several fields, such as green chemistry and environmental catalysis, in the synthesis of single-walled carbon nanotubes, as modifiers of Ni catalysts for methane steam and dry reforming reactions and in biological and electrochemistry applications. The range of reactions catalyzed by gold, as well as the suitability of different supports and the influence of the preparation conditions have been widely explored and optimized in applied research [2]. Gold catalysts appeared to be very different from the other noble metal-based catalysts, due to their marked dependence on the preparation method, which is crucial for the genesis of the catalytic activity. Several methods, including deposition-precipitation, chemical vapor deposition and cation adsorption, have been applied for the preparation of gold catalysts over reducible oxides, like TiO2. Among these methods, deposition-precipitation has been the most frequently employed method for Au loading, and it involves the use of tetrachloroauric (III acid as a precursor. On the other hand, the number of articles dealing with Au-loaded acidic supports is smaller than that on basic supports, possibly because the deposition of [AuCl4]− or [AuOHxCl4−x]− species on acidic supports is difficult, due to their very low point of zero charge. Despite this challenge, several groups have reported the use of acidic zeolites as supports for gold. Zeolites

  13. Fuel cell catalyst degradation

    DEFF Research Database (Denmark)

    Arenz, Matthias; Zana, Alessandro

    2016-01-01

    Fuel cells are an important piece in our quest for a sustainable energy supply. Although there are several different types of fuel cells, the by far most popular is the proton exchange membrane fuel cell (PEMFC). Among its many favorable properties are a short start up time and a high power density...... increasing focus. Activity of the catalyst is important, but stability is essential. In the presented perspective paper, we review recent efforts to investigate fuel cell catalysts ex-situ in electrochemical half-cell measurements. Due to the amount of different studies, this review has no intention to give...

  14. Aerogel derived catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, J. G., LLNL

    1996-12-11

    Aerogels area class of colloidal materials which have high surface areas and abundant mesoporous structure. SiO{sub 2} aerogels show unique physical, optical and structural properties. When catalytic metals are incorporated in the aerogel framework, the potential exists for new and very effective catalysts for industrial processes. Three applications of these metal-containing SiO{sub 2} aerogels as catalysts are briefly reviewed in this paper--NO{sub x} reduction, volatile organic compound destruction, and partial oxidation of methane.

  15. Olefin metathesis catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Kukes, S.G.; Banks, R.L.

    1986-05-20

    A process is described for preparing a disproportionation catalyst comprising admixing a catalytically effective amount of a calcined and activated catalyst consisting essentially of at least one metal oxide selected from molybdenum oxide and tungsten oxide and a support containing a major proportion of silica or alumina with a promoting amount of a methylating agent selected from the group consisting of dimethyl sulfate, dimethylsulfoxide, trimethyloxonium tetrafluorborate, methyl iodide, and methyl bromide, and subjecting same to inert atmospheric conditions for the methylating agent to promote the activity of the calcined molybdenum and tungsten oxides for the disproportionation of olefins.

  16. Dynamics of Catalyst Nanoparticles

    DEFF Research Database (Denmark)

    Hansen, Thomas Willum; Cavalca, Filippo; Wagner, Jakob Birkedal

    under gas exposure, dynamic phenomena such as sintering and growth can be observed with sub-Ångstrøm resolution. Metal nanoparticles contain the active sites in heterogeneous catalysts, which are important for many industrial applications including the production of clean fuels, chemicals...... and pharmaceuticals, and the cleanup of exhaust from automobiles and stationary power plants. Sintering, or thermal deactivation, is an important mechanism for the loss of catalyst activity. In order to initiate a systematic study of the dynamics and sintering of nanoparticles, various catalytic systems have been...

  17. Towards the Rational Design of Nanoparticle Catalysts

    Science.gov (United States)

    Dash, Priyabrat

    This research is focused on development of routes towards the rational design of nanoparticle catalysts. Primarily, it is focused on two main projects; (1) the use of imidazolium-based ionic liquids (ILs) as greener media for the design of quasi-homogeneous nanoparticle catalysts and (2) the rational design of heterogeneous-supported nanoparticle catalysts from structured nanoparticle precursors. Each project has different studies associated with the main objective of the design of nanoparticle catalysts. In the first project, imidazolium-based ionic liquids have been used for the synthesis of nanoparticle catalysts. In particular, studies on recyclability, reuse, mode-of-stability, and long-term stability of these ionic-liquid supported nanoparticle catalysts have been done; all of which are important factors in determining the overall "greenness" of such synthetic routes. Three papers have been published/submitted for this project. In the first publication, highly stable polymer-stabilized Au, Pd and bimetallic Au-Pd nanoparticle catalysts have been synthesized in imidazolium-based 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]PF6) ionic liquid (Journal of Molecular Catalysis A: Chemical, 2008, 286, 114). The resulting nanoparticles were found to be effective and selective quasi-homogeneous catalysts towards a wide-range of hydrogenation reactions and the catalyst solution was reused for further catalytic reactions with minimal loss in activity. The synthesis of very pure and clean ILs has allowed a platform to study the effects of impurities in the imidazolium ILs on nanoparticle stability. In a later study, a new mode of stabilization was postulated where the presence of low amounts of 1-methylimidazole has substantial effects on the resulting stability of Au and Pd-Au nanoparticles in these ILs (Chemical Communications, 2009, 812). In further continuation of this study, a comparative study involving four stabilization protocols for nanoparticle

  18. Long Term Time Variability of Cosmic Rays and Possible Relevance to the Development of Life on Earth

    Science.gov (United States)

    Erlykin, A. D.; Wolfendale, A. W.

    2010-07-01

    An analysis is made of the manner in which the cosmic ray intensity at Earth has varied over its existence and its possible relevance to both the origin and the evolution of life. Much of the analysis relates to the `high energy’ cosmic rays ( E > 1014 eV; =0.1 PeV) and their variability due to the changing proximity of the solar system to supernova remnants which are generally believed to be responsible for most cosmic rays up to PeV energies. It is pointed out that, on a statistical basis, there will have been considerable variations in the likely 100 My between the Earth’s biosphere reaching reasonable stability and the onset of very elementary life. Interestingly, there is the increasingly strong possibility that PeV cosmic rays are responsible for the initiation of terrestrial lightning strokes and the possibility arises of considerable increases in the frequency of lightnings and thereby the formation of some of the complex molecules which are the `building blocks of life’. Attention is also given to the well known generation of the oxides of nitrogen by lightning strokes which are poisonous to animal life but helpful to plant growth; here, too, the violent swings of cosmic ray intensities may have had relevance to evolutionary changes. A particular variant of the cosmic ray acceleration model, put forward by us, predicts an increase in lightning rate in the past and this has been sought in Korean historical records. Finally, the time dependence of the overall cosmic ray intensity, which manifests itself mainly at sub-10 GeV energies, has been examined. The relevance of cosmic rays to the `global electrical circuit’ points to the importance of this concept.

  19. Deactivation-resistant catalyst for selective catalyst reduction of NOx

    DEFF Research Database (Denmark)

    2011-01-01

    The present invention relates to a catalyst for selective catalytic reduction of NOx in alkali metal containing flue gas using ammonia as reductant, the catalyst comprising a surface with catalytically active sites, wherein the surface is at least partly coated with a coating comprising at least...... one metal oxide. In another aspect the present invention relates to the use of said catalyst and to a method of producing said catalyst. In addition, the present invention relates to a method of treating an catalyst for conferring thereon an improved resistance to alkali poisoning....

  20. Generalized joint hypermobility in childhood is a possible risk for the development of joint pain in adolescence

    DEFF Research Database (Denmark)

    Sohrbeck-Nøhr, Oline; Kristensen, Jens; Boyle, Eleanor;

    2014-01-01

    BackgroundThere is some evidence that indicates generalized joint hypermobility (GJH) is a risk factor for pain persistence and recurrence in adolescence. However, how early pain develops and whether GJH without pain in childhood is a risk factor for pain development in adolescence is undetermine...

  1. Mesoporous metal catalysts formed by ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Schaeferhans, Jana; Pazos Perez, Nicolas; Andreeva, Daria [Physikalische Chemie II, Universitaet Bayreuth (Germany)

    2010-07-01

    We study the ultrasound-driven formation of mesoporous metal sponges. The collapse of acoustic cavitations leads to very high temperatures and pressures on very short scales. Therefore, structures may be formed and quenched far from equilibrium. Mechanism of metal modification by ultrasound is complex and involves a variety of aspects. We propose that modification of metal particles and formation of mesoporous inner structures can be achieved due to thermal etching of metals by ultrasound stimulated high speed jets of liquid. Simultaneously, oxidation of metal surfaces by free radicals produced in water during cavitation stabilizes developed metal structures. Duration and intensity of the ultrasonication treatment is able to control the structure and morphology of metal sponges. We expect that this approach to the formation of nanoscale composite sponges is universal and opens perspective for a whole new class of catalytic materials that can be prepared in a one-step process. The developed method makes it possible to control the sponge morphology and can be used for formation of modern types of catalysts. For example, the sonication technique allows to combine the fabrication of mesoporous support and distribution of metal (Cu, Pd, Au, Pt etc.) nanoparticles in its pores into a single step.

  2. Characterization of Deactivated Bio-oil Hydrotreating Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Huamin; Wang, Yong

    2015-10-06

    Deactivation of bio-oil hydrotreating catalysts remains a significant challenge because of the poor quality of pyrolysis bio-oil input for hydrotreating and understanding their deactivation mode is critical to developing improved catalysts and processes. In this research, we developed an understanding of the deactivation of two-step bio-oil hydrotreating catalysts (sulfided Ru/C and sulfided CoMo/C) through detailed characterization of the catalysts using various complimentary analytical techniques. Severe fouling of both catalysts by carbonaceous species was the major form of deactivation, which is consistent with the significant loss of surface area and pore volume of both deactivated catalysts and the significant increase of the bulk density. Further analysis of the carbonaceous species by thermogravimetric analysis and x-ray photoelectron spectroscopy indicated that the carbonaceous species was formed by condensation reaction of active species such as sugars and sugar derivatives (aldehydes and ketones) in bio-oil feedstock during bio-oil hydrotreating under the conditions and catalysts used. Microscopy results did not show metal sintering of the Ru/C catalyst. However, X-ray diffraction indicated a probable transformation of the highly-active CoMoS phase in the sulfided CoMo/C catalyst to Co8S9 and MoS2 phase with low activity. Loss of the active site by transport of inorganic elements from the bio-oil and the reactor construction material onto the catalyst surface also might be a cause of deactivation as indicated by elemental analysis of spent catalysts.

  3. Bifunctional catalysts for the direct production of liquid fuels from syngas

    NARCIS (Netherlands)

    Sartipi, S.

    2014-01-01

    Design and development of catalyst formulations that maximize the direct production of liquid fuels by combining Fischer-Tropsch synthesis (FTS), hydrocarbon cracking, and isomerization into one single catalyst particle (bifunctional FTS catalyst) have been investigated in this thesis. To achieve th

  4. Sustainable utility of magnetically recyclable nano-catalysts in water: Applications in organic synthesis

    Science.gov (United States)

    Magnetically recyclable nano-catalysts and their use in aqueous media is a perfect combination for the development of greener sustainable methodologies in organic synthesis. It is well established that magnetically separable nano-catalysts avoid waste of catalysts or reagents and...

  5. Au@Void@TiO2 yolk-shell nanostructures as catalysts for the promotion of oxidation reactions at cryogenic temperatures

    Science.gov (United States)

    Lee, Ilkeun; Joo, Ji Bong; Yin, Yadong; Zaera, Francisco

    2016-06-01

    A new gold-titania catalyst has been developed for cryogenic oxidations based on a yolk-shell nanoarchitecture. The synthesis of those structures involves the sequential deposition of a sacrificial silica layer and a titania shell around well-defined gold nanoparticles followed by removal of the silica via NaOH etching. The resulting catalyst contains an amorphous titania shell with sodium titanate and silicon impurities that proved critical for the cryogenic activity; removal of those via HCl treatment kills most of the catalytic conversion. Oxidation of carbon monoxide is possible with this Au@Void@TiO2 catalyst at temperatures as low as 120 K, by a mechanism different than the one operative at room temperature that involves a weakly-adsorbed CO species with a Csbnd O stretching frequency of 2162 cm- 1, possibly at Au-TiO2 interfacial sites.

  6. A patient with possible TRALI who developed pulmonary hypertensive crisis and acute pulmonary edema during cardiac surgery.

    Science.gov (United States)

    Kojima, Taiki; Nishisako, Ryo; Sato, Hideo

    2012-06-01

    There are very few case reports of transfusion-related acute lung injury (TRALI) under close hemodynamic monitoring. We encountered a case of possible TRALI during on-pump coronary artery bypass grafting (CABG). A 66-year-old man who had undergone on-pump CABG was administered fresh frozen plasma (FFP). One hour after FFP transfusion, pulmonary hypertensive crisis and subsequent hypoxic decompensation occurred. A second cardiopulmonary bypass (CPB) was needed for circulatory and respiratory deterioration. Extracorporeal life support (ECLS), intraaortic balloon pumping (IABP), and nitric oxide therapy were required after the surgery. Despite the severity of the initial state, his recovery was comparatively smooth. ECLS and IABP were removed on postoperative day (POD)1; the patient was extubated and discharged from the ICU on POD7 and POD12, respectively. The diagnosis of TRALI was confirmed by human leukocyte antigen antibody detection in the administered FFP. In addition, lymphocytic immunofluorescence test showed that a cross-match of the plasma from the pooled FFP against the recipient leukocytes was positive. The clinical course of the pulmonary artery hypertension was followed by a decrease in dynamic lung compliance. The mechanism of this phenomenon is unclear. However, it might suggest the possibility of vasoconstriction or obstruction of the peripheral pulmonary artery preceding lung damage, as in the case in animal models reported previously.

  7. Possible Pathways for Increasing Natural Gas Use for Transportation (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Zigler, B.

    2014-10-01

    A collaborative partnership of DOE National Laboratories is working with DOE to identify critical RD&D needs to significantly increase the speed and breadth of NG uptake into the transportation sector. Drivers for increased utilization of natural gas for transportation are discussed. Key needs in research, development, and deployment are proposed, as well as possible pathways to address those needs. This presentation is intended to serve as a catalyst to solicit input from stakeholders regarding what technical areas they deem the most important.

  8. Research advances in the catalysts for the selective oxidation of ethane to aldehydes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhe; ZHAO Zhen; XU Chunming

    2005-01-01

    Selective oxidation of ethane to aldehydes is one of the most difficult processes in the catalysis researches of low alkanes. The development of selective oxidation of ethane to aldehydes (formaldehyde, acetaldehyde and acrolein) is discussed. The latest progress of the catalysts, including bulk or supported metal oxide catalysts, highly dispersed and isolated active sites catalysts, and the photo-catalytic ethane oxidation catalysts, partial oxidation of ethane in the gas phase, and the proposed reaction pathways from ethane to aldehydes are involved.

  9. Studies of Heterogeneous Catalyst Selectivity and Stability for Biorefining Applications

    Science.gov (United States)

    O'Neill, Brandon J.

    The conversion of raw resources into value-added end products has long underlain the importance of catalysts in economic and scientific development. In particular, the development of selective and stable heterogeneous catalysts is a challenge that continues to grow in importance as environmental, sociological, and economic concerns have motivated an interest in sustainability and the use of renewable raw materials. Within this context, biomass has been identified as the only realistic source of renewable carbon for the foreseeable future. The development of processes to utilize biomass feedstocks will require breakthroughs in fundamental understanding and practical solutions to the challenges related to selectivity and stability of the catalysts employed. Selectivity is addressed on multiple fronts. First, the selectivity for C-O bond scission reactions of a bifunctional, bimetallic RhRe/C catalyst is investigated. Using multiple techniques, the origin of Bronsted acidity in the catalyst and the role of pretreatment on the activity, selectivity, and stability are explored. In addition, reaction kinetics experiments and kinetic modeling are utilized to understand the role of chemical functional group (i.e. carboxylic acid versus formate ester) in determining the decarbonylation versus decarboxylation selectivity over a Pd/C catalyst. Finally, kinetic studies over Pd/C and Cu/gamma-Al2O3 were performed so that that may be paired with density functional theory calculations and microkinetic modeling to elucidate the elementary reaction mechanism, identify the active site, and provide a basis for future rational catalyst design. Next, the issue of catalyst stability, important in the high-temperature, liquid-phase conditions of biomass processing, is examined, and a method for stabilizing the base-metal nanoparticles of a Cu/gamma-Al2O 3 catalyst using atomic layer deposition (ALD) is developed. This advancement may facilitate the development of biorefining by enabling

  10. Nanopore and nanoparticle catalysts.

    Science.gov (United States)

    Thomas, J M; Raja, R

    2001-01-01

    The design, atomic characterization, performance, and relevance to clean technology of two distinct categories of new nanocatalysts are described and interpreted. Exceptional molecular selectivity and high activity are exhibited by these catalysts. The first category consists of extended, crystallographically ordered inorganic solids possessing nanopores (apertures, cages, and channels), the diameters of which fall in the range of about 0.4 to about 1.5 nm, and the second of discrete bimetallic nanoparticles of diameter 1 to 2 nm, distributed more or less uniformly along the inner walls of mesoporous (ca. 3 to 10 nm diameter) silica supports. Using the principles and practices of solid-state and organometallic chemistry and advanced physico-chemical techniques for in situ and ex situ characterization, a variety of powerful new catalysts has been evolved. Apart from those that, inter alia, simulate the behavior of enzymes in their specificity, shape selectivity, regio-selectivity, and ability to function under ambient conditions, many of these new nanocatalysts are also viable as agents for effecting commercially significant processes in a clean, benign, solvent-free, single-step fashion. In particular, a bifunctional, molecular sieve nanopore catalyst is described that converts cyclohexanone in air and ammonia to its oxime and caprolactam, and a bimetallic nanoparticle catalyst that selectively converts cyclic polyenes into desirable intermediates. Nanocatalysts in the first category are especially effective in facilitating highly selective oxidations in air, and those in the second are well suited to effecting rapid and selective hydrogenations of a range of organic compounds.

  11. Hydrogen evolution reaction catalyst

    Science.gov (United States)

    Subbaraman, Ram; Stamenkovic, Vojislav; Markovic, Nenad; Tripkovic, Dusan

    2016-02-09

    Systems and methods for a hydrogen evolution reaction catalyst are provided. Electrode material includes a plurality of clusters. The electrode exhibits bifunctionality with respect to the hydrogen evolution reaction. The electrode with clusters exhibits improved performance with respect to the intrinsic material of the electrode absent the clusters.

  12. Heterogeneous chromium catalysts

    NARCIS (Netherlands)

    2005-01-01

    The present invention relates to a heterogeneous chromium catalyst system for the polymerisation of ethylene and/or alpha olefins prepared by the steps of: (a) providing a silica-containing support, (b) treating the silica-containing support with a chromium compound to form a chromium-based silica-c

  13. Deactivation of Oxidation Catalysts

    Science.gov (United States)

    1991-05-01

    Levenspiel (Reference 10) have proposed an equivalent general expression of the form dS _KST (4) dtk to account for deactivation due to catalyst pore...Voorhies, A., IEC, 1954, vol. 37, p. 318. 10. Szepe, S., and 0. Levenspiel , Proc. 4th Europ. Symp. Chem. React. Eng., Pergamon Press, p. 265. 11. U.S

  14. Olefin metathesis and catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Kukes, S. G.; Banks, R. L.

    1985-05-14

    Olefins are converted into other olefins having different numbers of carbon atoms by contact with a catalyst comprising an inorganic refractory oxide support containing at least one of tungsten oxide and molybdenum oxide and a promoting amount of at least one methylating agent under conditions suitable for the methylating agent compounds to promote the activity of tungsten and molybdenum oxides for the disproportionation reaction.

  15. Catalysts for Environmental Remediation

    DEFF Research Database (Denmark)

    Abrams, B. L.; Vesborg, Peter Christian Kjærgaard

    2013-01-01

    The properties of catalysts used in environmental remediation are described here through specific examples in heterogeneous catalysis and photocatalysis. In the area of heterogeneous catalysis, selective catalytic reduction (SCR) of NOx was used as an example reaction with vanadia and tungsta...

  16. Hydrogenation of carbon dioxide by hybrid catalysts, direct synthesis of aromatic from carbon dioxide and hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Kuei Chikung; Lee Mindar (National Taiwan Univ., Taipei (Taiwan))

    1991-02-01

    To improve climatic conditions and to solve the carbon resource problem, it is desirable to develop techniques whereby carbon dioxide can be converted to valuable liquid hydrocarbons which can be used either as fuels or industrial raw materials. Direct synthesis of aromatics from carbon dioxide hydrogenation was investigated in a single stage reactor using hybrid catalysts composed of iron catalysts and HZSM-5 zeolite. Carbon dioxide was first converted to CO by the reverse water gas shift reaction, followed by the hydrogenation of CO to hydrocarbons on iron catalyst, and finally the hydrocarbons were converted to aromatics in HZSM-5. Under the operating conditions of 350{degree}C, 2100 kilopascals and CO{sub 2}/H{sub 2}={1/2} the maximum aromatic selectivity obtained was 22% with a CO{sub 2} conversion of 38% using fused iron catalyst combined with the zeolite. Together with the kinetic studies, thermodynamic analysis of the CO{sub 2} hydrogenation was also conducted. It was found that unlike Fischer Tropsch synthesis, the formation of hydrocarbons from CO{sub 2} may not be thermodynamically favored at higher temperature. However, the sufficiently high yields of aromatics possible with this process provides a route for the direct synthesis of high-octane gasoline from carbon dioxide. 24 refs., 9 figs., 5 tabs.

  17. Highly dispersed CoMoS phase on titania nanotubes as efficient HDS catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Cortes-Jacome, M.A.; Escobar, J.; Angeles Chavez, C.; Lopez-Salinas, E.; Romero, E.; Ferrat, G.; Toledo-Antonio, J.A. [Molecular Engineering Program, Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas 152, San Bartolo Atepehuacan, G.A. Madero, 07730 Mexico, D.F. (Mexico)

    2008-01-15

    Nanotubular titania (NT) to be used as support for CoMo-based hydrodesulfurization (HDS) catalyst was synthesized and characterized by various techniques. NT annealed at 400 C (under nitrogen) was constituted by nanotubes of {proportional_to}5.5 nm (internal diameter) and retained 236 m{sup 2}/g of surface area. Mo at 3 atoms/nm{sup 2} (nominal loading) and cobalt at Co/(Co + Mo) = 0.3 were impregnated under nearly neutral, acidic or basic media. By XPS analyses of NT-supported sulfided catalysts, highly dispersed MoS{sub 2} particles of low stacking degree (1-2 slabs) aligned along the nanotubes were observed by HR-TEM in all sulfided materials. The CoMo catalysts supported on nanostructured titania had dibenzothiophene (DBT) HDS activity (in pseudo first order kinetic constant basis) values {proportional_to}1.35 and {proportional_to}1.7 times (Mo impregnated under near neutral and basic media, respectively) higher to that of a commercial reference with alumina carrier. According to shifts to higher binding energy of the Co 2p peak corresponding to sulfided cobalt (as determined by XPS), MoS{sub 2} dispersed on NT support could be efficiently promoted by Co (''CoMoS'' phase formation), opening the possibility of developing new highly active HDS catalysts. (author)

  18. Catalysis by nonmetals rules for catalyst selection

    CERN Document Server

    Krylov, Oleg V

    1970-01-01

    Catalysis by Non-metals: Rules of Catalyst Selection presents the development of scientific principles for the collection of catalysts. It discusses the investigation of the mechanism of chemosorption and catalysis. It addresses a series of properties of solid with catalytic activity. Some of the topics covered in the book are the properties of a solid and catalytic activity in oxidation-reduction reactions; the difference of electronegativities and the effective charges of atoms; the role of d-electrons in the catalytic properties of a solid; the color of solids; and proton-acid and proton-ba

  19. Is it possible to bring the emancipatory practice development and evidence-based practice agendas together in nursing and midwifery?

    Directory of Open Access Journals (Sweden)

    Greg Fairbrother

    2015-05-01

    Full Text Available Background: The emancipatory practice development and evidence-based practice movements play significant roles in driving today’s nursing and midwifery practice and knowledge development agendas. Often, however, they are characterised as philosophically opposed to one another. Aims and objectives: To provide an overview of the philosophical and epistemological background to these two movements and locate them in relation to today’s overall nursing knowledge and practice development environment. Methods: Literature review, case study and model advance. Findings: The paper argues that a mutualised evidence-based emancipatory practice development (EBEPD is today both practical and achievable, and proposes a convergent model. The EBEPD model is discussed with particular reference to contemporary philosophical debate in nursing, some of which positions positivism (a primary underpin to evidence-based practice and critical realism (a primary underpin to emancipatory practice development as epistemologically irreconcilable. Conclusion and implications for practice: Significant knowledge and practice development opportunities are likely to emerge from working to bring together these two fundamentally important and arguably symbiotic movements in healthcare.

  20. Host-response to foot-and-mouth disease in cattle; possible implications for the development of persistently infected "carriers"

    DEFF Research Database (Denmark)

    Stenfeldt, Anna Carolina

    manuscript contains results from measurements of mRNA levels of inflammatory cytokines IFNα- and –β as well as tumor necrosis factor –α (TNF-α), in collected biopsy samples. The type 1 interferon response in the analyzed tissue samples is discussed in relation to the previously reported systemic interferon...... of mRNA levels of inflammatory cytokines in sequential biopsy samples. Structure of Thesis The first chapter contains general background information on the host response to virus infections, as well as characteristics of FMDV and the pathogenesis of the infection. Detailed aims and objectives...... response. The measured cytokine responses, as well as an observed variation in the TNF-α response between carriers and non-carriers, are discussed in relation to previous publications within the subject area. The third manuscript deals with investigations of possible sites of virus replication during early...

  1. A Possible Paradigm for the Mitigation of the Adverse Impacts of Natural Hazards in the Developing Countries

    Science.gov (United States)

    Aswathanarayana, U.

    2001-05-01

    The proneness of a country or region to a given natural hazard depends upon its geographical location, physiography, geological and structural setting, landuse/landcover situation, and biophysical and socioeconomic environments (e.g. cyclones and floods in Bangladesh, earthquakes in Turkey, drought in Sub-Saharan Africa). While the natural hazards themselves cannot be prevented, it is possible to mitigate their adverse effects, by a knowledge-based, environmentally-sustainable approach, involving the stakeholder communities: (i) by being prepared: on the basis of the understanding of the land conditions which are prone to a given hazard and the processes which could culminate in damage to life and property (e.g. planting of dense-rooted vegetation belts to protect against landslides in the earthquake-prone areas), (ii) by avoiding improper anthropogenic activities that may exacerbate a hazard (e.g. deforestation accentuating the floods and droughts), and (iii) by putting a hazard to a beneficial use, where possible (groundwater recharging of flood waters), etc. Mitigation strategies need to be custom-made for each country/region by integrating the biophysical and socioeconomic components. The proposed paradigm is illustrated in respect of Extreme Weather Events (EWEs), which is based on the adoption of three approaches: (i) Typology approach, involving the interpretation of remotely sensed data, to predict (say) temporal and spatial distribution of precipitation, (ii) "black box" approach, whereby the potential environmental consequences of an EWE are projected on the basis of previously known case histories, and (iii) Information Technology approach, to translate advanced technical information in the form of "virtual" do-it-yourself steps understandable to lay public.

  2. New catalysts for clean environment

    Energy Technology Data Exchange (ETDEWEB)

    Maijanen, A.; Hase, A. [eds.] [VTT Chemical Technology, Espoo (Finland)

    1996-12-31

    VTT launched a Research Programme on Chemical Reaction Mechanisms (CREAM) in 1993. The three-year programme (1993-1995) has focused on reaction mechanisms relevant to process industries and aimed at developing novel catalysts and biocatalysts for forest, food, and specialty chemicals industries as well as for energy production. The preliminary results of this programme have already been presented in the first symposium organized in Espoo in September 1994. To conclude the programme the second symposium is organized in Otaniemi, Espoo on January 29 - 30, 1996. Papers by 19 speakers and 17 poster presentations of the 1996 Symposium are included in this book. The Symposium consists of four sessions: Biotechnology for Natural Fibers Processing, New Biocatalysts, Catalysts for Clean Energy, and New Opportunities for Chemical Industry. The CREAM programme has tried to foresee solutions for the problems challenged by the public concern on environmental aspects, especially dealing with industrial processes and novel use of raw materials and energy. The programme has followed the basic routes that can lead to natural and simple solutions to develop processes in the fields of forest, food fine chemicals, and energy industry. This symposium presents the results of the programme to learn and further discuss together with the international experts that have been invited as keynote speakers. (author)

  3. Molybdenum sulfide/carbide catalysts

    Science.gov (United States)

    Alonso, Gabriel; Chianelli, Russell R.; Fuentes, Sergio; Torres, Brenda

    2007-05-29

    The present invention provides methods of synthesizing molybdenum disulfide (MoS.sub.2) and carbon-containing molybdenum disulfide (MoS.sub.2-xC.sub.x) catalysts that exhibit improved catalytic activity for hydrotreating reactions involving hydrodesulfurization, hydrodenitrogenation, and hydrogenation. The present invention also concerns the resulting catalysts. Furthermore, the invention concerns the promotion of these catalysts with Co, Ni, Fe, and/or Ru sulfides to create catalysts with greater activity, for hydrotreating reactions, than conventional catalysts such as cobalt molybdate on alumina support.

  4. Hydrodeoxygenation of Levulinic Acid over Supported Catalysts

    NARCIS (Netherlands)

    Luo, Wenhao

    2014-01-01

    Levulinic acid (LA), which can be produced from the sugar fractions of lignocellulosic biomass, is a promising sustainable platform molecule that can play a major role in future biorefineries. The work described was aimed at the development of heterogeneous catalysts for the selective conversion of

  5. Characteristics of CuO-MoO3-P2O5 catalyst and its catalytic wet oxidation (CWO) of dye wastewater under extremely mild conditions.

    Science.gov (United States)

    Ma, Hongzhu; Zhuo, Qiongfang; Wang, Bo

    2007-11-01

    In order to develop a catalyst with high activity for catalytic wet oxidation (CWO) processing at lower temperatures (35 degrees C) and atmospheric pressure, a new CuO-MoO3-P2O5 catalystwas synthesized by a solid-state reaction method and was characterized by X-ray diffraction (XRD), Fourier transformation infrared spectrometer (FTIR), X-ray photoelectron spectroscopy (XPS), selected area electronic diffraction (SAED), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDXS) for elemental mapping. Methylene blue (MB) was adopted to investigate the catalytic activity of CuO-MoO3-P2O5 in CWO processing. The results show that this new catalyst has a high catalytic activity to decolorize MB under mild condition. The color removal of MB (the initial concentration was 0.3 g L(-1) and initial pH was 5) can reach to 99.26% within 10 min at 35 degrees C and atmospheric pressure. Catalyst lifespan and selectivity were also tested, and the results show that after the catalyst was used three times, catalyst activity still remains. Selectivity testing shows that CuO-MoO3-P2O5 has high catalytic activity on degradation of MB, whereas this catalyst has less impact on methyl orange (the color removal was 99.65% for MB and 55% for methyl orange under the same conditions). According to the experimental results, a possible mechanism of catalytic degradation of MB was proposed.

  6. Hybrid-breeding of medicinally used valerian (Valeriana officinalis L. s.l.. A possible concept developing new varieties?

    Directory of Open Access Journals (Sweden)

    Penzkofer, Michael

    2016-07-01

    Full Text Available The aim of this work was to develop and verify a new concept for breeding new hybrid-varieties of valerian without a male sterility system. For this the cross-pollination rate and the performance of inbreeded plants must be determined.

  7. Room for action? How service managers in three Scandinavian cities experience their possibilities to develop their services

    Directory of Open Access Journals (Sweden)

    Næss Ole

    2014-06-01

    Full Text Available BACKGROUND - The study is based on the ongoing public debate concerning a limited scope for local service development in alcohol and drug treatment-related services - and that the main cause of local “paralysis” is to be found in health policy micromanagement of these services. It is argued that business management models place too much emphasis on financial control and performance measurement and that this leads to less interest in quality improvement in the provision of services. DESIGN - 23 interviews with service managers in three Nordic urban municipalities, Stavanger, Umeå and Aarhus. RESULTS - The article documents comprehensive local service development, demonstrating that the main conditions for innovation are management commitment and interdisciplinary co-operation in the practice field. CONCLUSIONS - In all three municipalities the services develop in a hybrid innovation model that combines New Public Management-inspired solutions with technical co-operation in horizontal networks. Results show that NPM-inspired solutions to alcohol and drug treatment services do not necessarily hinder the consideration of local professionalism and flexibility in the development.

  8. Supporting Professional Development in Special Education with Web-Based Professional Learning Communities: New Possibilities with Web 2.0

    Science.gov (United States)

    Hardman, Elizabeth L.

    2012-01-01

    This article describes the challenges in organizing professional learning communities (PLCs) in special education, identifies the teacher and student benefits of using a PLC approach to professional development, and discusses the promise and pitfalls of organizing web-based PLCs to engage distributed stakeholders in the practice of special…

  9. Alteration of gene expression in human cells treated with the agricultural chemical diazinon: possible interaction in fetal development.

    Science.gov (United States)

    Mankame, T; Hokanson, R; Fudge, R; Chowdhary, R; Busbee, D

    2006-05-01

    Agricultural chemicals frequently alter human health or development, typically because they have endocrine agonist or antagonist activities and alter hormone-regulation of gene expression. The insecticide, diazinon, was evaluated for gene expression disrupting activity using MCF-7 cells, an estrogen-dependent human cell line, to examine the capacity of the insecticide to disrupt gene expression essential for morphological development, immune system development or function, and/or central nervous system development and function. MCF-7 cells were treated with 30, 50 or 67 ppm diazinon, and gene expression was measured in treated cells compared to expression in untreated or estrogen-treated cells. DNA microarray analysis of diazinon-treated cells showed significant up- or down-regulation of a large number of genes compared to untreated cells. Of the 600 human genes on the Phase 1 chip utilized for these studies, two specific genes--calreticulin and TGF-beta3--were selected for corroboration using quantitative real time PCR (qrtPCR). qrtPCR, completed to assess gene expression levels for calreticulin and TGFbeta3, confirmed results showing significant up-regulation of these two genes obtained from the microarray data. These studies were designed to provide baseline data on the gene expression-altering capacity of a specific chemical, diazinon, and allow a partial assessment of the potentially deleterious effects associated with exposure of human cells to this chemical. Currently, it is not known whether results from cells in vitro can be extrapolated to human health consequences of chemical exposure.

  10. The importance of clinical mistletoe cancer therapy and korean mistletoe pharmacopuncture preparation development and application possibility for oriental medicine

    Directory of Open Access Journals (Sweden)

    Ok-Byung Choi

    2009-03-01

    Full Text Available Objectives : Mistletoe extracts have been in use for around 85 years, predominantly in the area of cancer therapy. Today mistletoe preparations are among the most prescribed drugs in cancer medicine, thus constituting a standard biological therapy in the area of oncology. The purpose of this study is to analyze the practical implications of mistletoe cancer therapy, their clinical status, their preparation techniques and companies. Contents : Mistletoe therapy for cancer has been developed within the context of anthroposophical medicine. One major effect of mistletoe extract is that it stimulates the immune system and cancer defences. In Germany, a total of eight different mistletoe preparations are available, five developed by Anthroposophic Medicine and three evolved from research in phytotherapy. Therapy always consists of an introductory phase in order to test the patient′s tolerance, find the right dosage and choose the most suitable preparation. This paper covers the background of mistletoe medical plant materials, mistletoe therapy for cancer, the anthroposophical medicine and clinical research, the practical regulation of treatment, preparation of mistletoe drugs. Result & suggestion : Mistletoe extracts are a complementary teratment of cancer, widely used in intergrative cancer care. The study of the integration of korean mistletoe extracts to oriental cancer medicine, its development and feasibility in Korea are urgently needed. The products, substances, compositions of european mistletoe drugs are very similar to those of oriental medicine theory. Applying the mistletoe cancer therapy and its preparation techniques to oriental medicine, the herbal acupuncture preparation should be modernized and korean mistletoe products are to be developed. To this end, government and herbal acupuncture society need to interact each other for the development of oriental mistletoe cancer medicine.

  11. Synthesis and characterization of catalysts and electrocatalysts using combinatorial methods

    Science.gov (United States)

    Ramanathan, Ramnarayanan

    This thesis documents attempts at solving three problems. Bead-based parallel synthetic and screening methods based on matrix algorithms were developed. The method was applied to search for new heterogeneous catalysts for dehydrogenation of methylcyclohexane. The most powerful use of the method to date was to optimize metal adsorption and evaluate catalysts as a function of incident energy, likely to be important in the future, should availability of energy be an optimization parameter. This work also highlighted the importance of order of addition of metal salts on catalytic activity and a portion of this work resulted in a patent with UOP LLC, Desplaines, Illinois. Combinatorial methods were also investigated as a tool to search for carbon-monoxide tolerant anode electrocatalysts and methanol tolerant cathode electrocatalysts, resulting in discovery of no new electrocatalysts. A physically intuitive scaling criterion was developed to analyze all experiments on electrocatalysts, providing insight for future experiments. We attempted to solve the CO poisoning problem in polymer electrolyte fuel cells using carbon molecular sieves as a separator. This approach was unsuccessful in solving the CO poisoning problem, possibly due to the tendency of the carbon molecular sieves to concentrate CO and CO 2 in pore walls.

  12. Laboratory evaluation of FCC commercial catalysts. Analysis of products of industrial importance

    Energy Technology Data Exchange (ETDEWEB)

    Passamonti, Francisco J.; De la Puente, Gabriela; Sedran, Ulises [Instituto de Investigaciones en Catalisis y Petroquimica (INCAPE, FIQ, UNL-CONICET), Santiago del Estero 2654, 3000 Santa Fe (Argentina)

    2008-04-15

    The results of the conversion of a VGO over six equilibrium commercial FCC catalysts with different formulations in a batch CREC Riser Simulator laboratory reactor at 500 and 550 C, catalyst to oil ratio 6.1 and reaction times from 3 to 30 s, were analyzed. It was possible to define the main catalyst characteristics in terms of various evaluation items, such as activity, gasoline yield and quality, LPG yield and coke yield, or the yields of particular compounds like, e.g., isobutane. Important differences in activity between catalysts were not observed, but catalyst properties reflected clearly as significant differences in gasoline, LPG or coke selectivities. Particularly, catalyst's hydrogen transfer properties impacted on gasoline composition and isobutane yield. The results showed that the CREC Riser Simulator reactor is an important tool for the evaluation of both commercial catalysts and feedstocks and process conditions. (author)

  13. The possibility of using photogrammetric and remote sensing techniques to model lavaka (gully erosion) development in Madagascar

    Science.gov (United States)

    Raveloson, Andrea; Székely, Balázs; Molnár, Gábor; Rasztovits, Sascha

    2013-04-01

    Gully erosion is a worldwide problem for it has a number of undesirable effects and their development is hard to follow. Madagascar is one of the most affected countries for its highlands are densely covered with gullies named lavakas. Lavaka formation and development seems to be triggered by many regional and local causes but the actual reasons are still poorly understood. Furthermore lavakas differ from normal gullies due to their enormous size and special shape. Field surveys are time consuming and data from two-dimensional measurements and pictures (even aerial) might lack major information for morphologic studies. Therefore close range surveying technologies should be used to get three-dimensional information about these unusual and complex features. This contribution discusses which remote sensing and photogrammetric techniques are adequate to survey the development of lavakas, their volume change and sediment budget. Depending on the types and properties (such as volume, depth, shape, vegetation) of the lavaka different methods will be proposed showing pros and cons of each one of them. Our goal is to review techniques to model, survey and analyze lavakas development to better understand the cause of their formation, special size and shape. Different methods are evaluated and compared from field survey through data processing, analyzing cost-effectiveness, potential errors and accuracy for each one of them. For this purpose we will also consider time- and cost-effectiveness of the softwares able to render the images into 3D model as well as the resolution and accuracy of the outputs. Further studies will concentrate on using the three dimensional models of lavakas which will be later on used for geomorphological studies in order to understand their special shape and size. This is ILARG-contribution #07.

  14. A Study of New Teacher Education for Professional Development : A Possibility of Professional School on Teacher Education in Japan

    OpenAIRE

    葛上, 秀文

    2006-01-01

    This paper focuses on the new reform of teacher education at graduate level by refering to PDS (Professional Development Schools) and NBPTS (National Board on Professional Teaching Standards) in U.S. In Japan, we are interested in teacher education at graduate level by recognizing educational crisises. I try to define new teaching pofession in Japan and to suggest a new curriculum of the professional school of teacher educaion, especially focusing contents of student teaching.

  15. Flavonoids, derived from traditional Chinese medicines, show roles in the differentiation of neurons: possible targets in developing health food products.

    Science.gov (United States)

    Xu, Sherry L; Zhu, Kevin Y; Bi, Cathy W C; Yan, Lu; Men, Simon W X; Dong, Tina T X; Tsim, Karl W K

    2013-12-01

    Flavonoids, a family of phenolic compounds, are distributed in a variety of fruits, vegetables, tea, and wine. More importantly, many flavonoids are served as the active ingredients in traditional Chinese herbal medicines, which in general do not have side effects. Several lines of evidence support that flavonoids have impacts on many aspects of human health, including anti-tumor, anti-oxidation, and anti-inflammation. Recently, there is significant attention focused on the neuronal beneficial effects of flavonoids, including the promotion of nervous system development, neuroprotection against neurotoxin stress, as well as the promotion of memory, learning, and cognitive functions. Here, the activities of flavonoids on the development of nervous system are being summarized and discussed. The flavonoids from diverse herbal medicines have significant effects in different developmental stages of nervous systems, including neuronal stem cell differentiation, neurite outgrowth, and neuronal plasticity. These findings imply that flavonoids are potential candidates for the development of health supplements in preventing birth defects and neuronal diseases.

  16. Can transcranial electrical stimulation improve learning difficulties in atypical brain development? A future possibility for cognitive training.

    Science.gov (United States)

    Krause, Beatrix; Cohen Kadosh, Roi

    2013-10-01

    Learning difficulties in atypical brain development represent serious obstacles to an individual's future achievements and can have broad societal consequences. Cognitive training can improve learning impairments only to a certain degree. Recent evidence from normal and clinical adult populations suggests that transcranial electrical stimulation (TES), a portable, painless, inexpensive, and relatively safe neuroenhancement tool, applied in conjunction with cognitive training can enhance cognitive intervention outcomes. This includes, for instance, numerical processing, language skills and response inhibition deficits commonly associated with profound learning difficulties and attention-deficit hyperactivity disorder (ADHD). The current review introduces the functional principles, current applications and promising results, and potential pitfalls of TES. Unfortunately, research in child populations is limited at present. We suggest that TES has considerable promise as a tool for increasing neuroplasticity in atypically developing children and may be an effective adjunct to cognitive training in clinical settings if it proves safe. The efficacy and both short- and long-term effects of TES on the developing brain need to be critically assessed before it can be recommended for clinical settings.

  17. Pathogenetics aspects of relationship mouth infectious diseases with development and progression atherosclerosis and possibility for their integrated prevention

    Directory of Open Access Journals (Sweden)

    M. V. Avdeeva

    2012-01-01

    Full Text Available The article contains the modern literature data about impact of various infectious agents on the development and progression of atherosclerotic disease. The data are demonstrated the role of various infectious diseases, including periodontal diseases, in the development of biological degradation and destabilization of atherosclerotic plaques. The article questions of organization of primary prevention of cardiovascular disease based on the screening assessment by stomatologist the oral sanitary status. Necessary to carry out sanitation of chronic infection foci of the mouth on the basis of existing children’s health centers. The children’s health centers have a set of dental equipment, with which can perform a screening diagnosis of dental caries, periodontal diseases, non-carious lesions, diseases of the mucous membranes, and conduct preventive oral sanitation. The duties of dental hygienists is teaching children of different age groups to the rules of oral care, demonstration of skills, brushing teeth, information about the importance of prevention of dental caries and periodontal disease, as it is not only important for the preservation of the teeth, but also may prevent the development of ardiovasculardisease adulthood.

  18. Genetic Syndromes and Genes Involved in the Development of the Female Reproductive Tract: A Possible Role for Gene Therapy.

    Science.gov (United States)

    Connell, Mt; Owen, Cm; Segars, Jh

    2013-01-01

    Müllerian and vaginal anomalies are congenital malformations of the female reproductive tract resulting from alterations in the normal developmental pathway of the uterus, cervix, fallopian tubes, and vagina. The most common of the Müllerian anomalies affect the uterus and may adversely impact reproductive outcomes highlighting the importance of gaining understanding of the genetic mechanisms that govern normal and abnormal development of the female reproductive tract. Modern molecular genetics with study of knock out animal models as well as several genetic syndromes featuring abnormalities of the female reproductive tract have identified candidate genes significant to this developmental pathway. Further emphasizing the importance of understanding female reproductive tract development, recent evidence has demonstrated expression of embryologically significant genes in the endometrium of adult mice and humans. This recent work suggests that these genes not only play a role in the proper structural development of the female reproductive tract but also may persist in adults to regulate proper function of the endometrium of the uterus. As endometrial function is critical for successful implantation and pregnancy maintenance, these recent data suggest a target for gene therapy. Future research will be needed to determine if gene therapy may improve reproductive outcomes for patients with demonstrated deficient endometrial expression related to abnormal gene expression.

  19. 多组分废催化剂中钯的分离工艺研究进展%Research development on the separation of Palladium from multicomponent waste catalyst

    Institute of Scientific and Technical Information of China (English)

    闫江梅; 董庆; 张之翔

    2014-01-01

    简述了废催化剂中钯分离回收的基本过程和方法,指出多组分废钯催化剂具有很高的回收价值,但存在组分多、分离困难的问题。对于多组分废钯催化剂中钯与贵金属金、银、铂、铑等,以及与非贵金属铜、钴、镍、铁等的分离技术分别进行了简要介绍与评价。结果表明,化学沉淀法、溶剂萃取法、还原法、置换法是目前多组分废钯催化剂常用的回收方法。其中化学沉淀法是使用最多的方法,但存在回收周期长、复杂、成本较高的问题,而溶剂萃取法具有分离效果好、过程简单的优点,成为最具发展前景的方法。因此选择性高、无污染并适合大规模工业化的萃取新工艺成为未来的发展方向。%This paper is aimed to briefly introduce basic process and method for the separation and recovery of palladium from waste catalyst,to point out that the multicomponent spent palladium catalysts have high recovery value,but there are so many components that its separation is very difficult. For multicomponent spent palladium catalyst,the separation techniques of palladium from precious metals gold,silver,platinum,rhodium,etc.,as well as from non-precious metals copper, cobalt,nickel,iron and other are briefly described and evaluated. The results show that chemical precipitation,solvent extraction,reduction,and displacement are commonly used methods for recycling multicomponent spent palladium catalyst. The chemical precipitation method is the most used method, but limited by long recycling cycle,complex process,and high cost;and solvent extraction method has good separation effect and simple process,becoming the most promising method. Therefore,a new extraction technology with high selectivity,pollution free and suitable for large-scale industrialization shall be focused in future development.

  20. The possibility of aromorphosis in further development of closed human life support systems using genetically modified organisms

    Science.gov (United States)

    Gitelson, Josef

    Creation of closed systems that would be able to support human life outside the biosphere for extended periods of time (CES) was started after humans went into outer space. The last fifty years have seen the construction of experimental variants of the CES in Russia, USA, and Japan. The "MELISSA" project of the European Space Agency is being prepared to be launched. Much success has been achieved in closing material loops in the CES. An obstacle to constructing a fully closed ecosystem is significant imbalance in material exchange between the producing components and the decomposing ones in the CES. The spectrum of metabolites released by humans does not fully correspond to the requirements of the main producer of the CES -plants. However, this imbalance can be corrected by rather simple physicochemical processes that can be used in the CES without unclosing the system. The major disagreement that prevents further improvement of human life support systems (LSS) is that the spectrum of products of photosynthesis in the CES does not correspond to human food requirements qual-itatively, quantitatively, or in terms of diversity. In the normal, physiologically sound, human diet, this discrepancy is resolved by adding animal products. However, there are technical, technological, and hygienic obstacles to including animals in the closed human life support systems, and if higher animals are considered, there are also ethical arguments. If between the photoautotrophic link, plants, and the heterotrophic link, the human, there were one more heterotrophic link, farm animals, the energy requirements of the system would be increased by nearly an order of magnitude, decreasing its efficiency and making it heavier and bulkier. Is there another way to close loops in human life support systems? In biology, such "findings" of evolution, which open up new perspectives and offer ample opportunities for possible adapta-tions, are termed aromorphoses (Schmalhausen, 1948). In further

  1. Formulation of cracking catalyst based on zeolite and natural clays

    Energy Technology Data Exchange (ETDEWEB)

    Aliev, R.R.; Lupina, M.I.

    1995-11-01

    Domestically manufactured cracking catalysts are based on a synthetic amorphous aluminosilicate matrix and Y zeolite. A multistage {open_quotes}gel{close_quotes} technology is used in manufacturing the catalysts. The process includes mixing solutions of sodium silicate and acidic aluminum sulfate, forming, syneresis, and activation of the beaded gel. In the manufacture of bead catalysts, the next steps in the process are washing, drying, and calcining; in the manufacture of microbead catalysts, the next steps are dispersion and formation of a hydrogel slurry, spray-drying, and calcining. The Y zeolite is either introduced into the alumina-silica sol in the stage of forming the beads, or introduced in the dispersion stage. With the aim of developing an active and selective cracking catalyst based on Y zeolite and natural clays, with improved physicomechanical properties, the authors carried out a series of studies, obtaining results that are set forth in the present article.

  2. Possibilities of information infrastructure in evaluation of environmental pollution and water quality by implementing the solutions of sustainable development

    Directory of Open Access Journals (Sweden)

    Ramutė Naujikienė

    2014-10-01

    Full Text Available The purpose – of the article is attached to the examination of information infrastructure for the assessment of water resource planning and water treatment activities, to provide data warehouse (DW analysis measuring environmental and water pollution and indicators for the evaluation based on the requirements of sustainable development.Methodology – the analysis is performed by revealing the factors affecting sustainable development decisions. The insights of scientists are demonstrated by assessing the situation of environmental pollution, the appropriate search parameters, which allow revealing environmental and water contamination by waste water. Secondary data analysis was performed in order to reveal surface water contamination assessment districts in Lithuania and the Baltic Sea region and to summarise the results.It is very important for business activities to implement methods and tools based on a sense of responsibility for environmental pollution through the use of methods for increasing corporate responsibility, supporting measures to promote stimulation resulting in emission reduction, and efficiency of techniques. The paper presents the results of surface water pollution obtained according to the monitoring data and benchmarking analysis in the districts of Lithuania and the Baltic Sea. It can be concluded that the economic factors of enterprise functioning on the occasion of pollution also impacts the pollution of the Baltic Sea.More and more attention in the sustainable development of the implementation process should be given to decreasing population and increasing responsibility of economic operators for measures of environmental management levels: strategic and tactical planning, operational control, evaluation of economic, social and ecological balance. The regulatory importance in determining the impact on the environment should also be kept in mind.The results – were based on the obtained wastewater monitoring and

  3. Possible roles for folic acid in the regulation of trophoblast invasion and placental development in normal early human pregnancy.

    Science.gov (United States)

    Williams, Paula J; Bulmer, Judith N; Innes, Barbara A; Broughton Pipkin, Fiona

    2011-06-01

    In addition to its role in the prevention of neural tube defects, folic acid has many other physiological functions, including cell proliferation, DNA replication, and antioxidant protection. The aim of this study was to determine the role that folic acid has in regulating placental trophoblast development. Placental explants from placentae at gestational age 7 wk (n = 3) were cultured in folic acid at concentrations of 10(-6) M, 10(-8) M, and 10(-10) M. Extravillous trophoblast (EVT) invasion was assessed following 6-day culture, and explants were used for immunohistochemical evaluation of proliferation (MKI67) and apoptosis (active caspase 3). In addition, an array was performed on cell culture supernatants to examine a range of matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs). Folic acid increased the invasion of EVT cells in this explant model by between 83% and 19% (P = 0.005), and this was associated with increased MKI67 positivity and decreased active caspase 3 positivity; this effect was concentration dependent and showed a biphasic response. In addition, culture in folic acid increased vascular density, as determined by anti-CD31 immunostaining (P = 0.05). The increase in EVT invasion correlated with increased placental explant secretion of MMP2 (P = 0.01), MMP3 (P = 0.01), and MMP9 (P = 0.02). This study demonstrates that folic acid is potentially important in a number of crucial early stages of placental development, including EVT invasion, angiogenesis, and secretion of MMPs, and highlights the need for further studies to address the benefit of longer-term folic acid supplementation throughout pregnancy to prevent pregnancy disorders associated with deficient placental development, including preeclampsia.

  4. [Possibilities and problems in the development of forensic nursing in Japan: a questionnaire survey of clinical nurses].

    Science.gov (United States)

    Kodama, Hiromi; Tsuntematsu, Kayoko; Yanai, Keiko

    2012-09-01

    Forensic nursing scientifically obtains and preserves the criminal damage from victims of domestic violence, child abuse, elder abuse, sexual violence and other related forms of violence. This was developed in North America in the 1980s, and has carried out appropriate nursing care while protecting the human rights of victims. Serious crime in Japan has been increasing, and it would seem that forensic nursing opportunities should expand as well. However, in Japan, there hasn't been much discussion about forensic nursing. Theorizing that support for clinical forensic nursing should be recognized and relevant, we carried out a survey of 581 clinical nurses to investigate the development of forensic nursing in Japan. 93 clinical nurses (16.0%) had a low level of familiarity with forensic nursing; however, 324 nurses (56.3%) had encountered patients who had suffered violence. 264 nurses (45.4%) had a feeling of wanting to be involved in forensic nursing, but were not confident with the knowledge and technology, while 144 nurses (24.8%) were concerned about the larger responsibility they would have. 400 nurses (68.8%) hoped to receive specialized knowledge and technical education. It is necessary to establish an education system for forensic nursing in accordance with the educational status-quo while considering the present state of forensic nursing education.

  5. Skills development and structural change: Possibilities for and limitations of redressing structural racial inequalities in South Africa

    Science.gov (United States)

    Groener, Zelda

    2013-12-01

    Improving structural racial equality for historically-disadvantaged Black South Africans, including low-skilled and unemployed adults and youths, is a pertinent challenge for the South African government during the ongoing transition from apartheid capitalism to post-apartheid capitalism. Within the framework of the National Skills Development Strategy (NSDS), the introduction of "learnerships" and "learning programmes", which include structured learning programmes, learnerships, apprenticeships and skills programmes, has had some impact. But emerging theoretical perspectives assert that apartheid structural racial inequalities persist and that structural reform is imperative. Opposing positions translate into two perspectives on social transition: either capitalism can be de-racialised, or capitalism in South Africa should be dismantled in order to de-racialise it. After a review of relevant literature and governmental documents, the author identifies five structural and pedagogical barriers as likely causes for low completion rates of skills development courses and concludes that structural reform needs more favourable political and economic conditions in order to be successful.

  6. Occupational exposure to pesticides as a possible risk factor for the development of chronic diseases in humans

    Science.gov (United States)

    Gangemi, Silvia; Miozzi, Edoardo; Teodoro, Michele; Briguglio, Giusi; De Luca, Annamaria; Alibrando, Carmela; Polito, Irene; Libra, Massimo

    2016-01-01

    It is well known that pesticides are widely used compounds. In fact, their use in agriculture, forestry, fishery and the food industry has granted a huge improvement in terms of productive efficiency. However, a great number of epidemiological surveys have demonstrated that these toxic compounds can interact and exert negative effects not only with their targets (pests, herbs and fungi), but also with the rest of the environment, including humans. This is particularly relevant in the case of workers involved in the production, transportation, preparation and application of these toxicants. Accordingly, a growing body of evidence has demonstrated the correlation between occupational exposure to pesticides and the development of a wide spectrum of pathologies, ranging from eczema to neurological diseases and cancer. Pesticide exposure is often quite difficult to establish, as many currently used modules do not take into account all of the many variables that can occur in a diverse environment, such as the agricultural sector, and the assessment of the real risk for every single worker is problematic. Indeed, the use of personal protection equipment is necessary while handling these toxic compounds, but education of workers can be even more important: personal contamination with pesticides may occur even in apparently harmless situations. This review summarises the most recent findings describing the association between pesticide occupational exposure and the development of chronic diseases. PMID:27748877

  7. Possibilities for a sustainable development. Muligheter for en baerekraftig utvikling; Analyser paa ''World Model''

    Energy Technology Data Exchange (ETDEWEB)

    Bjerkholt, O.; Johnsen, T.; Thonstad, K.

    1993-01-01

    This report is the final report of a project that the Central Bureau of Statistics of Norway has carried out. The report present analyses of the relations between economic development, energy consumption and emission of pollutants to air in a global perspective. The analyses are based on the ''World Model'', that has been developed at the Institute for Economic Analysis at New York University. The analyses show that it will be very difficult to obtain a global stabilization of the CO[sub 2] emission on the 1990 level. In the reference scenario of the United Nations report ''Our Common Future'', the increase of CO[sub 2] emissions from 1990 to 2020 was 73%. Even in the scenario with the most drastic measures, the emissions in 2020 will be about 43% above the 1990 level, according to the present report. A stabilization of the global emissions at the 1990 level will require strong measures beyond those assumed in the model calculations, or a considerable breakthrough in energy technology. 17 refs., 5 figs., 21 tabs.

  8. Fluorination process using catalysts

    Science.gov (United States)

    Hochel, R.C.; Saturday, K.A.

    1983-08-25

    A process is given for converting an actinide compound selected from the group consisting of uranium oxides, plutonium oxides, uranium tetrafluorides, plutonium tetrafluorides and mixtures of said oxides and tetrafluorides, to the corresponding volatile actinide hexafluoride by fluorination with a stoichiometric excess of fluorine gas. The improvement involves conducting the fluorination of the plutonium compounds in the presence of a fluoride catalyst selected from the group consisting of CoF/sub 3/, AgF/sub 2/ and NiF/sub 2/, whereby the fluorination is significantly enhanced. The improvement also involves conducting the fluorination of one of the uranium compounds in the presence of a fluoride catalyst selected from the group consisting of CoF/sub 3/ and AgF/sub 2/, whereby the fluorination is significantly enhanced.

  9. Fluorination process using catalyst

    Science.gov (United States)

    Hochel, Robert C.; Saturday, Kathy A.

    1985-01-01

    A process for converting an actinide compound selected from the group consisting of uranium oxides, plutonium oxides, uranium tetrafluorides, plutonium tetrafluorides and mixtures of said oxides and tetrafluorides, to the corresponding volatile actinide hexafluoride by fluorination with a stoichiometric excess of fluorine gas. The improvement involves conducting the fluorination of the plutonium compounds in the presence of a fluoride catalyst selected from the group consisting of CoF.sub.3, AgF.sub.2 and NiF.sub.2, whereby the fluorination is significantly enhanced. The improvement also involves conducting the fluorination of one of the uranium compounds in the presence of a fluoride catalyst selected from the group consisting of CoF.sub.3 and AgF.sub.2, whereby the fluorination is significantly enhanced.

  10. Photo catalyst; Ko shokubai

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    While titanium oxide is excited by the light, electrons of titanium oxide are taken away by the light energy to form positive holes. Water will be decomposed into hydrogen ion and hydroxy radical (OH) by these positive holes. This hydroxy radical is a strong reactive substance called active oxygen, it decomposes organisms. Besides this photo- catalyst function, the titanium oxide can also make surface of a substance superhydrophilic. The super hydrophilicity results in not forming water drops on the glass surface but spreading all over the surface to prevent a covering of fog on the glass surface. The published patents concerning the photo catalysts were 593 from Jan. 1998 to Jan. 1999. The applicant order is the first TOTO 143, the second Daikin Industry 19, the third Toshiba Raitech, Nitto Denko, Hitachi 17 respectively. (NEDO)

  11. Sulfur tolerant zeolite supported platinum catalysts for aromatics hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Bergem, Haakon

    1997-12-31

    The increased demand for transportation fuels at the expence of heavier fuel oil has forced the refinery industry to expand their conversion capacity with hydrotreating as one of the key processes. A shift towards more diesel powered vehicles along with tightening fuel regulations demanding cleaner fuels has lead to increasing interest in catalytic processes for the manufacturing of such environmentally acceptable fuels. This provides the motivation for this thesis. Its main objective was to study possible catalysts active for desulfurization, hydrogenation, and ring-opening of aromatics all in the presence of sulfur. A close examination of the physical properties and kinetical behaviour of the chosen catalysts has been performed. A high pressure reactor setup was designed and built for activity measurements. Zeolite supported platinum catalysts were prepared and both the metal and acid functions were characterized utilizing various experimental techniques. Hydrogenation of toluene was used as a model reaction and the effect of sulfur adsorption on the activity and kinetic behaviour of the catalysts was investigated. The catalyst samples showed hydrogenation activities comparable to a commercial Pt/Al2O3 catalyst. There were no clear differences in the effect of the various sulfur compounds studied. Platinum supported on zeolite Y gave considerably more sulfur tolerant catalysts compared to Al2O3 as support. 155 refs., 58 figs., 36 tabs.

  12. Host cell and expression engineering for development of an E. coli ketoreductase catalyst: Enhancement of formate dehydrogenase activity for regeneration of NADH

    Directory of Open Access Journals (Sweden)

    Mädje Katharina

    2012-01-01

    Full Text Available Abstract Background Enzymatic NADH or NADPH-dependent reduction is a widely applied approach for the synthesis of optically active organic compounds. The overall biocatalytic conversion usually involves in situ regeneration of the expensive NAD(PH. Oxidation of formate to carbon dioxide, catalyzed by formate dehydrogenase (EC 1.2.1.2; FDH, presents an almost ideal process solution for coenzyme regeneration that has been well established for NADH. Because isolated FDH is relatively unstable under a range of process conditions, whole cells often constitute the preferred form of the biocatalyst, combining the advantage of enzyme protection in the cellular environment with ease of enzyme production. However, the most prominent FDH used in biotransformations, the enzyme from the yeast Candida boidinii, is usually expressed in limiting amounts of activity in the prime host for whole cell biocatalysis, Escherichia coli. We therefore performed expression engineering with the aim of enhancing FDH activity in an E. coli ketoreductase catalyst. The benefit resulting from improved NADH regeneration capacity is demonstrated in two transformations of technological relevance: xylose conversion into xylitol, and synthesis of (S-1-(2-chlorophenylethanol from o-chloroacetophenone. Results As compared to individual expression of C. boidinii FDH in E. coli BL21 (DE3 that gave an intracellular enzyme activity of 400 units/gCDW, co-expression of the FDH with the ketoreductase (Candida tenuis xylose reductase; XR resulted in a substantial decline in FDH activity. The remaining FDH activity of only 85 U/gCDW was strongly limiting the overall catalytic activity of the whole cell system. Combined effects from increase in FDH gene copy number, supply of rare tRNAs in a Rosetta strain of E. coli, dampened expression of the ketoreductase, and induction at low temperature (18°C brought up the FDH activity threefold to a level of 250 U/gCDW while reducing the XR activity by

  13. Olefin metathesis and catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Kukes, S. G.; Banks, R. L.

    1985-03-12

    Olefins are converted into other olefins having different numbers of carbon atoms by contact with a catalyst comprising an inorganic refractory material containing at least one of tungsten oxide and molybdenum oxide and a promoting amount of at least one treating agent selected from chlorinated silicon compounds, thionyl chloride, and sulfuryl chloride under conditions suitable for the treating agent to promote the activity of tungsten and molybdenum oxides for the disporoportionation reaction.

  14. About the role of Westerly Wind Events in the possible development of an El Niño in 2014

    Science.gov (United States)

    Menkes, Christophe E.; Lengaigne, Matthieu; Vialard, Jérôme; Puy, Martin; Marchesiello, Patrick; Cravatte, Sophie; Cambon, Gildas

    2014-09-01

    Similarities between early 1997 and 2014 has prompted climate scientists to wonder if an El Niño matching the 1997 "El Niño of the century" could develop in 2014. Until April 2014, the equatorial Pacific exhibited positive heat content anomalies along with an eastward warm pool displacement similar to those found during the onset of strong El Niño events. Yet in July 2014, the warm pool had retreated back to its climatological positions and equatorial temperature anomalies were much weaker than in mid-1997. Dedicated oceanic simulations reveal that these weak interannual anomalies can be attributed to differences in Westerly Wind Event (WWE) sequences. In contrast with 1997, the lack of WWEs from April to June significantly limited the growth of eastern Pacific anomalies and the eastward warm pool displacement in 2014. With the absence of additional WWE activity, prospects for a mature El Niño in late 2014 are fading.

  15. Host response to Foot- and Mouth Disease infection in cattle; possible implications for the development of “carriers”

    DEFF Research Database (Denmark)

    Stenfeldt, Carolina; Heegaard, Peter M. H.; Tjørnehøj, Kirsten

    to the disease. The FMDV infection is defined as persistent when live virus can be detected for more than 28 days post infection. FMD infection in ruminants involves initial viral replication in pharyngeal epithelia, from where the virus spreads systemically. Characteristic vesicular lesions develop......, as well as samples of lymphoid tissue derived from staged post mortems were analysed for the presence of viral proteins through indirect immunoflourescence. These samples have also been analysed for the presence of specific populations of immune cells such as CD8+ T-cells and Dendritic cells. Biopsy...... for the presence of viral genomes as well as FMDV-specific antibodies. Viral shedding was measured through qPCR of mouth swabs and oropharyngeal fluid (probang samples). Tissue samples derived from endoscopical collection of biopsies of the dorsal soft palate from live animals at different times post infection...

  16. Glucocorticoids Distinctively Modulate the CFTR Channel with Possible Implications in Lung Development and Transition into Extrauterine Life.

    Directory of Open Access Journals (Sweden)

    Mandy Laube

    Full Text Available During fetal development, the lung is filled with fluid that is secreted by an active Cl- transport promoting lung growth. The basolateral Na+,K+,2Cl- cotransporter (NKCC1 participates in Cl- secretion. The apical Cl- channels responsible for secretion are unknown but studies suggest an involvement of the cystic fibrosis transmembrane conductance regulator (CFTR. CFTR is developmentally regulated with a high expression in early fetal development and a decline in late gestation. Perinatal lung transition is triggered by hormones that stimulate alveolar Na+ channels resulting in fluid absorption. Little is known on how hormones affect pulmonary Cl- channels. Since the rise of fetal cortisol levels correlates with the decrease in fetal CFTR expression, a causal relation may be assumed. The aim of this study was to analyze the influence of glucocorticoids on pulmonary Cl- channels. Alveolar cells from fetal and adult rats, A549 cells, bronchial Calu-3 and 16HBE14o- cells, and primary rat airway cells were studied with real-time quantitative PCR and Ussing chambers. In fetal and adult alveolar cells, glucocorticoids strongly reduced Cftr expression and channel activity, which was prevented by mifepristone. In bronchial and primary airway cells CFTR mRNA expression was also reduced, whereas channel activity was increased which was prevented by LY-294002 in Calu-3 cells. Therefore, glucocorticoids strongly reduce CFTR expression while their effect on CFTR activity depends on the physiological function of the cells. Another apical Cl- channel, anoctamin 1 showed a glucocorticoid-induced reduction of mRNA expression in alveolar cells and an increase in bronchial cells. Furthermore, voltage-gated chloride channel 5 and anoctamine 6 mRNA expression were increased in alveolar cells. NKCC1 expression was reduced by glucocorticoids in alveolar and bronchial cells alike. The results demonstrate that glucocorticoids differentially modulate pulmonary Cl

  17. Glucocorticoids Distinctively Modulate the CFTR Channel with Possible Implications in Lung Development and Transition into Extrauterine Life.

    Science.gov (United States)

    Laube, Mandy; Bossmann, Miriam; Thome, Ulrich H

    2015-01-01

    During fetal development, the lung is filled with fluid that is secreted by an active Cl- transport promoting lung growth. The basolateral Na+,K+,2Cl- cotransporter (NKCC1) participates in Cl- secretion. The apical Cl- channels responsible for secretion are unknown but studies suggest an involvement of the cystic fibrosis transmembrane conductance regulator (CFTR). CFTR is developmentally regulated with a high expression in early fetal development and a decline in late gestation. Perinatal lung transition is triggered by hormones that stimulate alveolar Na+ channels resulting in fluid absorption. Little is known on how hormones affect pulmonary Cl- channels. Since the rise of fetal cortisol levels correlates with the decrease in fetal CFTR expression, a causal relation may be assumed. The aim of this study was to analyze the influence of glucocorticoids on pulmonary Cl- channels. Alveolar cells from fetal and adult rats, A549 cells, bronchial Calu-3 and 16HBE14o- cells, and primary rat airway cells were studied with real-time quantitative PCR and Ussing chambers. In fetal and adult alveolar cells, glucocorticoids strongly reduced Cftr expression and channel activity, which was prevented by mifepristone. In bronchial and primary airway cells CFTR mRNA expression was also reduced, whereas channel activity was increased which was prevented by LY-294002 in Calu-3 cells. Therefore, glucocorticoids strongly reduce CFTR expression while their effect on CFTR activity depends on the physiological function of the cells. Another apical Cl- channel, anoctamin 1 showed a glucocorticoid-induced reduction of mRNA expression in alveolar cells and an increase in bronchial cells. Furthermore, voltage-gated chloride channel 5 and anoctamine 6 mRNA expression were increased in alveolar cells. NKCC1 expression was reduced by glucocorticoids in alveolar and bronchial cells alike. The results demonstrate that glucocorticoids differentially modulate pulmonary Cl- channels and are likely

  18. The possibility of coexistence and co-development in language competition: ecology-society computational model and simulation.

    Science.gov (United States)

    Yun, Jian; Shang, Song-Chao; Wei, Xiao-Dan; Liu, Shuang; Li, Zhi-Jie

    2016-01-01

    Language is characterized by both ecological properties and social properties, and competition is the basic form of language evolution. The rise and decline of one language is a result of competition between languages. Moreover, this rise and decline directly influences the diversity of human culture. Mathematics and computer modeling for language competition has been a popular topic in the fields of linguistics, mathematics, computer science, ecology, and other disciplines. Currently, there are several problems in the research on language competition modeling. First, comprehensive mathematical analysis is absent in most studies of language competition models. Next, most language competition models are based on the assumption that one language in the model is stronger than the other. These studies tend to ignore cases where there is a balance of power in the competition. The competition between two well-matched languages is more practical, because it can facilitate the co-development of two languages. A third issue with current studies is that many studies have an evolution result where the weaker language inevitably goes extinct. From the integrated point of view of ecology and sociology, this paper improves the Lotka-Volterra model and basic reaction-diffusion model to propose an "ecology-society" computational model for describing language competition. Furthermore, a strict and comprehensive mathematical analysis was made for the stability of the equilibria. Two languages in competition may be either well-matched or greatly different in strength, which was reflected in the experimental design. The results revealed that language coexistence, and even co-development, are likely to occur during language competition.

  19. BIOPROSPECTING AS A POSSIBLE DEVELOPMENT MECHANISM FOR COLOMBIA Bioprospección como posible mecanismo de desarrollo para Colombia

    Directory of Open Access Journals (Sweden)

    LUZ MARINA MELGAREJO

    2013-04-01

    Full Text Available Bioprospecting has been on the agenda for discussion by the government, the academic community, businesses and other pertinent actors for many years now; it is an integral topic representing a potential approach to exploit biodiversity to the fullest. This document presents some definitions of what bioprospecting is (some restrictive, others with a broader perspective, depending on different approaches, actors, target markets and countries in the context of a mechanism for development and cooperation concerning the construction of capacities, advantages and disadvantages. It was found that bioprospecting in Colombia has been developing from a broad perspective (systematic study of biological-genetic resources, transformation into a product which has led to strengthening some value chains, small- and/or large-scale marketing and some advances in intellectual property rights and the distribution of benefits in order to provide greater benefits for the nation.La bioprospección ha sido durante varios años tema de discusión por los gobiernos, la comunidad académica, las empresas, y otros actores que se integran en el proceso, como potencial de acercamiento y uso de la diversidad biológica. A través del presente documento se presentan algunas definiciones de lo que es la bioprospección (algunas restrictivas otras de perspectiva amplia, dependientes de diferentes aproximaciones, actores, blanco de mercado, contexto del país, entre otros, la bioprospección como mecanismo de desarrollo y cooperación para la construcción de capacidades, ventajas y desventajas. Se encuentra que en Colombia se ha venido desarrollando bioprospección desde la perspectiva amplia (estudio sistemático del recurso biológico-genético, transformación en un producto lo que ha permitido el fortalecimiento de algunas cadenas de valor, comercialización a pequeña o gran escala y algunos avances en temas de propiedad intelectual y distribución de beneficios lo cual

  20. Dispersed catalysts for co-processing and coal liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Bockrath, B.; Parfitt, D.; Miller, R. [Pittsburgh Energy Technology Center, PA (United States)

    1995-12-31

    The basic goal is to improve dispersed catalysts employed in the production of clean fuels from low value hydrocarbons. The immediate objective is to determine how the properties of the catalysts may be altered to match the demands placed on them by the properties of the feedstock, the qualities of the desired end products, and the economic constraints put upon the process. Several interrelated areas of the application of dispersed catalysts to co-processing and coal conversion are under investigation. The first involves control of the selectivity of MoS{sub 2} catalysts for HDN, HDS, and hydrogenation of aromatics. A second area of research is the development and use of methods to evaluate dispersed catalysts by means of activity and selectivity tests. A micro-flow reactor has been developed for determining intrinsic reactivities using model compounds, and will be used to compare catalysts prepared in different ways. Micro-autoclaves will also be used to develop data in batch experiments at higher partial pressures of hydrogen. The third area under investigation concerns hydrogen spillover reactions between MoS{sub 2} catalysts and carbonaceous supports. Preliminary results obtained by monitoring H{sub 2}/D{sub 2} exchange reactions with a pulse-flow microreactor indicate the presence of spillover between MoS{sub 2} and a graphitic carbon. A more complete study will be made at a later stage of the project. Accomplishments and conclusions are discussed.