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Auswahl der wissenschaftlichen Literatur zum Thema „Catalyst carrier“
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Zeitschriftenartikel zum Thema "Catalyst carrier"
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Teng, Yingyue, Dingze Liu, Qiang Li, Xue Bai und Yinmin Song. „Research Progress on Application in Energy Conversion of Silicon Carbide-Based Catalyst Carriers“. Catalysts 13, Nr. 2 (19.01.2023): 236. http://dx.doi.org/10.3390/catal13020236.
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In modern industrial production, heterogeneous catalysts play an important role. A catalyst carrier, as a constituent of heterogeneous catalysts, is employed for supporting and loading active components. The catalyst carrier has a considerable impact on the overall acting performance of the catalysts in actual production. Therefore, a catalyst carrier should have some necessary properties such as a high specific surface area, excellent mechanical strength and wear resistance, and better thermal stability. Among the candidate materials, silicon carbide (SiC) has excellent physical and chemical properties due to its special crystal structure; these properties include outstanding thermal conductivity and remarkable mechanical strength and chemical stability. Therefore, SiC materials with a high specific surface area basically meet the requirements of catalyst carriers. Accordingly, SiC has broad application prospects in the field of catalysis and is an ideal material for preparing catalyst carriers. In the present study, we reviewed the preparation methods and the variation in the raw materials used for preparing SiC-based catalyst carriers with high specific surface areas, in particular the research progress on the application of SiC-based catalyst carriers in the field of energy-conversion in recent years. The in-depth analysis indicated that the construction of SiC with a special structure, large-scale synthesis of SiC by utilizing waste materials, low-temperature synthesis of SiC, and exploring the interaction between SiC supports and active phases are the key strategies for future industrial development; these will have far-reaching significance in enhancing catalytic efficiency, reutilization of resources, ecological environmental protection, energy savings, and reductions in energy consumption.
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Alexandrova, Julia V., Nataliya V. Maltseva, Tatiana A. Vishnevskaya und Shamil O. Omarov. „INFLUENCE TECHNOLOGY OF PREPARATION ON PROPERTIES Al-Ce-Zr-CARRIERS“. Bulletin of the Saint Petersburg State Institute of Technology (Technical University) 55 (2020): 3–9. http://dx.doi.org/10.36807/1998-9849-2020-55-81-3-9.
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The possibility of using Al-Ce-Zr-oxide carrier as a catalyst in the composition of NiO-catalyst in СО oxidation reaction by atmosphere oxygen – as a model oxidation reaction – was shown. The properties of carriers obtained by impregnation and mixing were compared, and the characteristics of the catalytic activity of Al-Ce-Zr-oxide carriers and NiO-catalysts based on them were determined in comparison with the NiO-catalyst deposited on an aluminum oxide carrier.
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Zhao, Yue Qing, Qian Yi Jia, Ying Hua Liang, Hong Xia Guo, Feng Feng Li und Xin Hua Liu. „CuO-CoO-MnO/SiO2 Nanocomposite Aerogel as Catalysts Carrier and Its Cocatalysis Mechanism in the Synthesis of Diphenyl Carbonate“. Advanced Materials Research 284-286 (Juli 2011): 707–10. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.707.
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CuO-CoO-MnO/SiO2 nanocomposite aerogel as catalysts carrier was prepared via sol-gel process and CO2supercritical drying (SCD) technique. Catalyst supported by the nanocomposite aerogel was prepared via impregnation method. The catalyst was used for the synthesis of diphenyl carbonate (DPC), and the yield of DPC in mass is up to 26.31%. The catalysis system of PdCl2/Co(OAc)2-Cu(OAc)2-Mn(OAc)2/TBAB/H2BQ is favorable to the synthesis of DPC. PdCl2, acetates of transition metals and H2BQ were the key catalyst, inorganic cocatalyst and organic cocatalyst, respectively. TBAB was the surface active agent of Pd0and stabilizer of Pd2+in the catalysis system.
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Bao, Jianguo, Wenxiu Rao, Yi Zhou, Bin Wen, Bo Wang, Guocheng Lv und Libing Liao. „Effect of the Microstructure of Support Materials on Cracking Catalyst Performance“. Crystals 13, Nr. 1 (10.01.2023): 123. http://dx.doi.org/10.3390/cryst13010123.
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Fluid catalytic cracking (FCC) is a production process that converts petroleum into petroleum products in the presence of catalysts. The performance of an FCC catalyst plays a decisive role in petroleum refining. An FCC catalyst mainly comprises a molecular sieve (catalytic cracking active center), a carrier, and a binder. The carrier can enable the precracking of the heavy oil in its large pore, which can improve the overall activity of the catalyst and the conversion rate of heavy oil. The surface area and pore structure of carrier materials with different microscopic morphologies differ, which significantly affects the precracking of heavy oil molecules. Therefore, here, FCC catalysts were prepared using flake kaolinite, tubular halloysite, natural flake-tube-combined kaolinite, and mixed kaolinite as support materials, respectively. The FCC catalysts were used in FCC-heavy oil, and the influence of the carrier material morphology on the comprehensive performance of the catalysts was studied. The strength and cracking performance of the catalyst prepared using flake Maoming (M) were poor, whereas the catalyst prepared using tubular halloysite exhibited a good strength, high activity, and a good cracking ability for heavy oil. The catalyst prepared using natural flake-tube combined with Suzhou (S) exhibited a good strength and cracking performance, and it has been widely used in the industrial production of FCC catalysts. When 40% tube-like halloysite was mixed into M, the attrition of the prepared catalyst decreased by 0.5 units, the microreactivity increased by 1.4 units, the gasoline + liquefied petroleum gas (LPG) yield increased by 3.09 percentage points, and the gasoline research octane number (RON) increased by 0.6 units. The comprehensive performance of the catalyst can reach or exceed that of the natural-lamp-tube-based kaolin carrier. The results can not only provide guidance for the stable quality control of kaolin, but they can also significantly alleviate the resource restrictions for FCC catalyst production enterprises.
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Yang, Rui Qin, Xi Kun Gai, Chuang Xing, Jian Wei Mao und Cheng Xue Lv. „Performance of Cu-Based Catalysts in Low-Temperature Methanol Synthesis“. Advanced Materials Research 1004-1005 (August 2014): 1623–26. http://dx.doi.org/10.4028/www.scientific.net/amr.1004-1005.1623.
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The reactions of the methanol synthesis were conducted from the CO/CO2/H2 on the Cu-based catalysts using different solvent at 443 K and 3.0 MPa. The alcohol solvent had the activity in the low-temperature methanol synthesis reaction. The activity of the Cu-based catalyst with ZnO as carrier was higher than that of the catalyst with CeO2, Al2O3, or TiO2 as carrier separately in the reaction. The addition of the CeO2 to the Cu/ZnO catalysts improved the copper species dispersion, so that it was easier for the reduction of the Cu/CeO2-ZnO catalyst than that of the Cu/ZnO catalyst according to the TPR analysis. The variation trend of the BET surface area and the copper surface area was consistent with those of the activity for the Cu/ZnO and the Cu/CeO2-ZnO catalysts in the reaction. The activity of the Cu/CeO2-ZnO catalyst was higher than that of the Cu/ZnO catalyst in the reaction.
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Smołka, Szymon, und Katarzyna Krukiewicz. „Catalyst Design through Grafting of Diazonium Salts—A Critical Review on Catalyst Stability“. International Journal of Molecular Sciences 24, Nr. 16 (08.08.2023): 12575. http://dx.doi.org/10.3390/ijms241612575.
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In the pursuit of designing a reusable catalyst with enhanced catalytic activity, recent studies indicate that electrochemical grafting of diazonium salts is an efficient method of forming heterogeneous catalysts. The aim of this review is to assess the industrial applicability of diazonium-based catalysts with particular emphasis on their mechanical, chemical, and thermal stability. To this end, different approaches to catalyst production via diazonium salt chemistry have been compared, including the immobilization of catalysts by a chemical reaction with a diazonium moiety, the direct use of diazonium salts and nanoparticles as catalysts, the use of diazonium layers to modulate wettability of a carrier, as well as the possibility of transforming the catalyst into the corresponding diazonium salt. After providing descriptions of the most suitable carriers, the most common deactivation routes of catalysts have been discussed. Although diazonium-based catalysts are expected to exhibit good stability owing to the covalent bond created between a catalyst and a post-diazonium layer, this review indicates the paucity of studies that experimentally verify this hypothesis. Therefore, use of diazonium salts appears a promising approach in catalysts formation if more research efforts can focus on assessing their stability and long-term catalytic performance.
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Liao, Yalong, Yiyang Wang und Yu Zhang. „Preparation and Catalytic Hydrodechlorination Property of Nano Bimetallic Catalyst Pd–Ni/γAl2O3–SiO2“. Catalysts 12, Nr. 4 (24.03.2022): 370. http://dx.doi.org/10.3390/catal12040370.
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Pd–Ni bimetallic catalyst supported on a composite carrier of γAl2O3 and SiO2 was prepared by chemical precipitation methodology enhanced with an ultrasonic wave. In the present paper, the influence of dispersant, carrier, ultrasonic time and intensity on the dechlorination property of the catalysts obtained are investigated. The appearance, morphology and structure of the prepared catalysts were characterized using X-ray diffraction (XRD), scanning transmission electron microscopy (STEM), N2 adsorption–desorption isotherm and X-ray photoelectron spectroscopy spectrometer (XPS). The chemical composition of active gradients in the catalysts was tested with inductively coupled plasma-atomic emission spectrometry (ICP-AES). The metal dispersion and mean particle size of the metallic phase of the prepared catalysts were also determined with CO chemisorption. Results indicate that a nano bimetal Pd–Ni catalyst on an average particle size of 2.45 nm with a distribution range of 1–7 nm supported on a composite carrier of γAl2O3 and SiO2 can be effectively prepared, and that the chlorine content of shellac dechlorinated with the obtained catalyst is 0.18 wt%, which is lower than that reported in the previous literature, indicating the perfect dechlorination property of the catalyst.
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Feng, Wenli, Xuebin Lu, Jian Xiong, Zhihao Yu, Yilin Wang, Jianguo Cui, Rui Zhang und Rengui Weng. „Solid–Waste–Derived Geopolymer–Type Zeolite–like High Functional Catalytic Materials Catalyze Efficient Hydrogenation of Levulinic Acid“. Catalysts 12, Nr. 11 (04.11.2022): 1361. http://dx.doi.org/10.3390/catal12111361.
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Three common solid wastes (waste incineration fly ash, sewage sludge, and polluted soil) were the raw materials used in the synthesis of a geopolymer–type zeolite–like product, which was then used as a catalyst carrier to prepare a nickel hydrogenation catalyst for the catalytic hydrogenation of levulinic acid to γ–valerolactone. Under optimum synthesis conditions, the synthesized geopolymer zeolite has excellent structure and performance. The characterization results show that the composites have a three–dimensional network structure, and the pore structure is homogeneous mesoporous or microporous. In this work, the results of catalytic hydrogenation show that the yield of γ–valerolactone can achieve up to 94% using the synthesized catalyst, which is comparable to that of commercial catalysts and the concentrations of typical polluting heavy metals of Cu, Zn, Pb, and Cd in the reaction solution were all below the emission concentration limit (Class I standard) after five cycles of reaction. In summary, this geopolymer–type zeolite–like catalyst is cheap and has excellent performance; it is, therefore, expected to be widely used in catalysis instead of commercial carriers.
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Kurta, Sergiy, Ihor Mykytyn, Victoria Ribun und Olga Khatsevich. „Features of the structure active centers of industrial catalysts for the oxidative chlorination of ethylene“. International Journal of Engineering & Technology 7, Nr. 2.23 (20.04.2018): 307. http://dx.doi.org/10.14419/ijet.v7i2.23.12751.
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The active phase of CuCl2, HСuСl2, H2СuСl4 and two grades of industrial ethylene oxidation chlorination catalysts (EOC) such as deposited catalyst X1 (Harshow), with copper chlorides supported on an alumina surface, and a permeated MEDC-B catalyst immobilized in the internal pores of the firm of the company Sud-Chemie. Catalyst were analyzed by the method of thermoemission electronic raster (VEGA3NTSCAN) microscopy and X-ray fluorescence energy dispersion spectroscopy (EDX-7000). It is shown that the active catalyst centers of CuCl2 have different crystalline structure from the amorphous active phase of H2CuCl2, H2CuCl4 on the surface of the catalysts. On the surface of X1 Harshow copper chlorides are uniformly distributed throughout the volume of the carrier catalyst γ-Al2O3 in the form of amorphous portions [CuCl4]-2, [CuCl2]-1. At the same time, on the surface of the catalyst MEDC-B, the active centers have a separate cluster immobilized crystalline structure of the active phase, which differs from the composition of the carrier γ-Al2O3.
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Tian, Qingbin, Lansen Bi, Shuyan Lin, Jiangshan Gao und Yan He. „A review of cold plasma for catalyst synthesis and modification“. Clean Energy Science and Technology 2, Nr. 1 (29.03.2024): 131. http://dx.doi.org/10.18686/cest.v2i1.131.
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Cold plasma has been extensively studied and developed in the field of energy storage and conversion, with a focus on its ability to assist in catalyst synthesis, surface modification, the introduction of heteroatoms, the generation of defects and vacancies, the improvement of catalyst dispersion, and the reduction of particle size. In contrast to conventional calcination and chemical methods, the energy from cold plasma can be transferred directly to the catalyst and carrier during the treatment process, which can improve the interaction between the loaded catalyst and carrier by changing the internal structure and surface morphology of the catalyst. Therefore, these properties make cold plasma quite green, safe, and efficient for catalyst synthesis and modification. In this paper, the characteristics and applications of various cold plasma technologies, as well as the synergistic treatment of cold plasma technology with thermodynamic principles on catalysts, are analyzed. Based on current research progress, this paper provides a summary and outlook on the synthesis and modification of catalysts using cold plasma.
Dissertationen zum Thema "Catalyst carrier"
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Couroyer, Charlotte G. M. „Attrition of alumina catalyst carrier beads“. Thesis, University of Surrey, 2000. http://epubs.surrey.ac.uk/843669/.
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Attrition of alumina catalyst carrier beads in reforming units causes operational problems and the loss of the catalyst particles due to the formation of fines and small fragments. This thesis addresses the characterisation and optimisation of the mechanical strength of these beads in collaboration with Institut Francais du Petrole (IFP) and Rhodia. A methodology was devised to test and improve the particle strength at various strain rates using both single particle and multiple particle tests by considering the mechanical stresses prevailing in industrial units. This methodology was tested with a commercial sample and then used to assess the strength of new samples for which the bead structure was modified by changing the filler concentration and type, the macroporosity, the drying regime and the surfactant concentration. A significant increase in the particle strength was achieved in comparison with the commercial samples. The mean crushing strength increased by a factor of about three and the extent of impact attrition was significantly decreased, e.g. by a factor of 30 for normal impacts at 20 m s-1. For single particle testing, a relationship between quasi-static and impact results was obtained when the impact breakage was compared with the percentage of weak particles obtained from the side crushing strength (SCS) test. This suggests that for this type of material the particle strength is not sensitive to the strain rate. Multiple particle tests confirmed the results obtained by single particle tests for two samples for which sufficient quantity of test material was available. In order to relate the extent of attrition in a particle assembly under compressive loading to the single particle properties, the BCS test was simulated by distinct element analysis using the TRUBAL code. Trends similar to the experimental work were obtained for the simulation of the attrition. However, the simulations tend to underestimate slightly the extent of attrition, which is highly dependent on the particle strength distribution and on the contact force distribution within the particle assembly. As a result of this work, the manufacture of the alumina catalyst carrier beads used in reforming units has been significantly improved.
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Miyazaki, Kazunari. „Studies on proton-conducting ceramic fuel cells for hydrogen-carrier utilization“. Kyoto University, 2020. http://hdl.handle.net/2433/254526.
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3
Ferri, Giulia. „Identification and study of relevant descriptors of the solid during the synthesis of boehmite“. Electronic Thesis or Diss., université Paris-Saclay, 2021. http://www.theses.fr/2021UPASG064.
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Un support catalytique en alumine doit avoir des propriétés mécaniques et thermiques adéquates, et favoriser un transfert de masse et de chaleur approprié. Ces propriétés dépendent de la texture du support, qui est le résultat du procédé de fabrication. Cette thèse se concentre sur l’opération unitaire de peptisation et malaxage, qui implique la dispersion d’une poudre de boehmite dans une solution acide. Une base est ensuite ajoutée pour induire l’agglomération des particules de boehmite dispersées. Ce procédé, réalisé sous agitation, permet de contrôler la taille et la structure des agglomérats d’alumine qui constitueront le support solide du catalyseur. Ce travail vise à modéliser la structure solide de l’alumine en fonction des paramètres physico-chimiques qui dirigent l’agglomération colloïdale, en absence des forces hydrodynamiques. Afin d’étudier l’impact du pH, de la force ionique et de la concentration sur la cinétique de coagulation, trois techniques expérimentales sont utilisées : la diffusion dynamique de la lumière (DLS), la diffusion des rayons X aux petits angles (SAXS) et la microscopie électronique à transmission (STEM). Les résultats expérimentaux sont interprétés à travers l’équation du bilan de population, alimentée par un modèle de dynamique Brownienne. Les résultats du bilan de population sont ensuite utilisés pour paramétrer un modèle morphologique d’agglomération, afin de simuler de grands volumes de la structure poreuse du solide d’alumine. Le modèle morphologique fait partie des nouvelles contributions de cette thèse, et permet de calculer les propriétés texturales d’un grain de boehmiteAn alumina catalyst carrier must have adequate mechanical and thermal properties, and promote an appropriate mass and heat transfer. These properties depend on the carrier texture, which is the result of its manufacturing process. Our study focuses on the peptization and kneading process, which involves the dispersion of boehmite powder in an acid solution. A base is then added to induce the agglomeration of dispersed boehmite particles. This process, performed under mixing, enables to tune the size and structure of the boehmite agglomerates that will build the solid catalyst carrier. This work aims at modeling the alumina solid structure depending on the physical-chemical parameters that drive the colloidal agglomeration when no hydrodynamic forces are present. In order to study the impact of pH, ionic strength and concentration on the coagulation kinetics, three experimental techniques are used: Dynamic Light Scattering (DLS), Small Angle X-Ray Scattering (SAXS) and Scanning Transmission Electron Microscopy (STEM). The results of the experimental data are interpreted in terms of the population-balance equation, where the size-structure relationship is given by a Brownian dynamics model. The results of the population-balance model are then used as inputs for a morphological agglomeration model, to simulate large volumes of the porous structure of the real alumina solid. Such a model is one of the new contributions of this work, and enables to compute textural properties of a boehmite grain
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Векшин, Віталій Олександрович. „Очищення викидних газів абсорбції від оксидів нітрогену у виробництві нітратної кислоти“. Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/22711.
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Дисертація на здобуття наукового ступеню кандидата технічних наук за спеціальністю 05.17.01 – Технологія неорганічних речовин. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2016.
Дисертація присвячена розробці технології приготування каталізатору для промислових процесів селективного каталітичного відновлення (СКВ) оксидів нітрогену аміаком. На основі експериментальних досліджень визначені оптимальні параметри технології підготовки носія на основі оксиду титану для подальшого нанесення каталітично активної речовини. Встановлені оптимальні умови нанесення активної речовини – платини – з розчину H₂[PtCl₆] на поверхню носія, а саме: число просочень – 1, час просочення – 5 хв., концентрація розчину для просочення – 10%. Доведений позитивний вплив модифікаторів у процесі приготування каталізаторів методом просочення. Фізико-хімічними дослідженнями обґрунтовано застосування в процесі просочення мурашиної кислоти, в якості конкуруючого адсорбату, та доведені її відновлюючи властивості. Проведені експериментальні дослідження стосовно впливу промислових параметрів (температури, об’ємної швидкості) на активність отриманих каталізаторів. Показано кореляцію між розміром платинових кристалітів та тривалістю експлуатації каталізатора, що підпорядковується експоненціальній залежності і показує зменшення часу роботи каталізатора зі збільшенням розміру кристалітів при спіканні. Створено математичну модель процесу. Досліджені кінетичні характеристики процесу відновлення NOx аміаком, що дозволило визначити оптимальні умови процесу очищення: Т = 473 – 523 К, об'ємна швидкість 50 000 – 60 000 м³/год на каталізаторі, модифікованому мурашиною кислотою. Розроблено блочний каталізатор, реактор відновлення до нього та запропоновано принципову схему виробництва. Виконано техніко-економічне обґрунтування виробництва блочного каталізатору та проведена еколого-економічна оцінка його роботи. Показано, що розроблений каталізатор має гідравлічний опір в 12 разів нижче, ніж у промислового АВК-10. Еколого-економічні розрахунки показали, що зниження газового опору та зменшення у 2,5 рази екологічних витрат призведе до економії в розмірі 16 038 720 грн протягом 8 років, тобто протягом всього періоду роботи каталізатора.Thesis for a Candidate of Techical Sciences degree by speciality 05.17.01 – Technology of inorganic substances. – National technical university "Kharkov polytechnical institute", Kharkov, 2016. Thesis is devoted to the development of technology for preparing the catalyst for industrial processes of selective catalytic reduction (SCR) of nitrogen oxides with ammonia. Optimal technological parameters of preparation of carrier based of titanium oxide for following impregnation with catalytically active substance have been experimentally determined. Optimal parameters of application of the active substance – platinum – from solution of hexachloroplatinic acid on the surface of carrier have been found: the number of impregnations is 1, the impregnation time is 5 min, the concentration of the impregnation solution is 10%. The positive influence of modifiers – monobasic organic acids – on the catalyst preparation by impregnation has been proved. Application of formic acid in impregnation as a competing adsorbate and as a reducing agent has been substantiated by means of physico-chemical investigations. Experimental researches of the influence of industrial parameters (temperature, gas hourly space velocity) on the activity of obtained catalysts have been carried out. Correlation between the size of platinum crystallites and the time of catalyst operation has been determined. It obeys the exponential dependence and shows decrease in running time of the catalyst with increase in size of crystallites during sintering. Mathematical model of the SCR process has been developed. Kinetic investigations of the process of NOx reduction on obtained catalysts have been carried out. They allowed to determine the optimal conditions of purification, which are as follows: the maximum degree of reduction can be achieved at T = 473 – 523 K and the bulk gas flow 50 000 – 60 000 m³/h on a catalyst modified with formic acid. The designs of the block catalyst having cellular structure and industrial reactor for it have been suggested. It is shown that the gas flow resistance of the developed catalyst is 12 times lower than that of the ABK-10. Ecological-economic calculations and economic benefit estimation show that decrease of gas flow resistance and 2.5-fold ecological costs reduction will result in savings of 16,038,720 UAH during 8 years, i.e. during full period of catalyst operation.
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Векшин, Віталій Олександрович. „Очищення викидних газів абсорбції від оксидів нітрогену у виробництві нітратної кислоти“. Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/22710.
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Дисертація на здобуття наукового ступеню кандидата технічних наук за спеціальністю 05.17.01 – Технологія неорганічних речовин. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2016.
Дисертація присвячена розробці технології приготування каталізатору для промислових процесів селективного каталітичного відновлення (СКВ) оксидів нітрогену аміаком. На основі експериментальних досліджень визначені оптимальні параметри технології підготовки носія на основі оксиду титану для подальшого нанесення каталітично активної речовини. Встановлені оптимальні умови нанесення активної речовини – платини – з розчину H₂[PtCl₆] на поверхню носія, а саме: число просочень – 1, час просочення – 5 хв., концентрація розчину для просочення – 10%. Доведений позитивний вплив модифікаторів у процесі приготування каталізаторів методом просочення. Фізико-хімічними дослідженнями обґрунтовано застосування в процесі просочення мурашиної кислоти, в якості конкуруючого адсорбату, та доведені її відновлюючи властивості. Проведені експериментальні дослідження стосовно впливу промислових параметрів (температури, об’ємної швидкості) на активність отриманих каталізаторів. Показано кореляцію між розміром платинових кристалітів та тривалістю експлуатації каталізатора, що підпорядковується експоненціальній залежності і показує зменшення часу роботи каталізатора зі збільшенням розміру кристалітів при спіканні. Створено математичну модель процесу. Досліджені кінетичні характеристики процесу відновлення NOx аміаком, що дозволило визначити оптимальні умови процесу очищення: Т = 473 – 523 К, об'ємна швидкість 50 000 – 60 000 м³/год на каталізаторі, модифікованому мурашиною кислотою. Розроблено блочний каталізатор, реактор відновлення до нього та запропоновано принципову схему виробництва. Виконано техніко-економічне обґрунтування виробництва блочного каталізатору та проведена еколого-економічна оцінка його роботи. Показано, що розроблений каталізатор має гідравлічний опір в 12 разів нижче, ніж у промислового АВК-10. Еколого-економічні розрахунки показали, що зниження газового опору та зменшення у 2,5 рази екологічних витрат призведе до економії в розмірі 16 038 720 грн протягом 8 років, тобто протягом всього періоду роботи каталізатора.Thesis for a Candidate of Techical Sciences degree by speciality 05.17.01 – Technology of inorganic substances. – National technical university "Kharkov polytechnical institute", Kharkov, 2016. Thesis is devoted to the development of technology for preparing the catalyst for industrial processes of selective catalytic reduction (SCR) of nitrogen oxides with ammonia. Optimal technological parameters of preparation of carrier based of titanium oxide for following impregnation with catalytically active substance have been experimentally determined. Optimal parameters of application of the active substance – platinum – from solution of hexachloroplatinic acid on the surface of carrier have been found: the number of impregnations is 1, the impregnation time is 5 min, the concentration of the impregnation solution is 10%. The positive influence of modifiers – monobasic organic acids – on the catalyst preparation by impregnation has been proved. Application of formic acid in impregnation as a competing adsorbate and as a reducing agent has been substantiated by means of physico-chemical investigations. Experimental researches of the influence of industrial parameters (temperature, gas hourly space velocity) on the activity of obtained catalysts have been carried out. Correlation between the size of platinum crystallites and the time of catalyst operation has been determined. It obeys the exponential dependence and shows decrease in running time of the catalyst with increase in size of crystallites during sintering. Mathematical model of the SCR process has been developed. Kinetic investigations of the process of NOx reduction on obtained catalysts have been carried out. They allowed to determine the optimal conditions of purification, which are as follows: the maximum degree of reduction can be achieved at T = 473 – 523 K and the bulk gas flow 50 000 – 60 000 m³/h on a catalyst modified with formic acid. The designs of the block catalyst having cellular structure and industrial reactor for it have been suggested. It is shown that the gas flow resistance of the developed catalyst is 12 times lower than that of the ABK-10. Ecological-economic calculations and economic benefit estimation show that decrease of gas flow resistance and 2.5-fold ecological costs reduction will result in savings of 16,038,720 UAH during 8 years, i.e. during full period of catalyst operation.
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Jang, Yong-Jun. „Nanosized polymer carriers for metallocene catalysts in heterogeneous olefin polymerization“. [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=976096374.
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Lindner-Lopez, Eduard. „Heterogenised palladium catalysts and magnetic carriers for fine chemicals production“. Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.416028.
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Carriel, Schmitt Caroline [Verfasser]. „Catalytic upgrading of fast pyrolysis bio-oils applying nickel-based catalysts / Caroline Carriel Schmitt“. Karlsruhe : KIT-Bibliothek, 2021. http://d-nb.info/1225401259/34.
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Gleichweit, Christoph Verfasser], Hans-Peter [Akademischer Betreuer] Steinrück und Jörg [Akademischer Betreuer] [Libuda. „Dehydrogenation of Liquid Organic Hydrogen Carriers on Model Catalyst Surfaces / Christoph Gleichweit. Gutachter: Hans-Peter Steinrück ; Jörg Libuda“. Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2015. http://d-nb.info/1079718621/34.
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Zhou, Shanshan. „PORE-CONFINED CARRIERS AND BIOMOLECULES IN MESOPOROUS SILICA FOR BIOMIMETIC SEPARATION AND TARGETING“. UKnowledge, 2017. http://uknowledge.uky.edu/cme_etds/78.
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Selectively permeable biological membranes composed of lipophilic barriers inspire the design of biomimetic carrier-mediated membranes for aqueous solute separation. This work imparts selective permeability to lipid-filled pores of silica thin film composite membranes using carrier molecules that reside in the lipophilic self-assemblies. The lipids confined inside the pores of silica are proven to be a more effective barrier than bilayers formed on the porous surface through vesicle fusion, which is critical for quantifying the function of an immobilized carrier. The ability of a lipophilic carrier embedded in the lipid bilayer to reversibly bind the target solute and transport it through the membrane is demonstrated. Through the functionalization of the silica surface with enzymes, enzymatic catalysis and biomimetic separations can be combined on this nanostructured composite platform. The successful development of biomimetic nanocomposite membrane can provide for efficient dilute aqueous solute upgrading or separations using engineered carrier/catalyst/support systems.
While the carrier-mediated biomimetic membranes hold great potential, fully understanding of the transport processes in composite synthetic membranes is essential for improve the membrane performance. Electrochemical impedance spectroscopy (EIS) technique is demonstrated to be a useful tool for characterizing the thin film pore accessibility. Furthermore, the effect of lipid bilayer preparation methods on the silica thin film (in the form of pore enveloping, pore filling) on ion transport is explored, as a lipid bilayer with high electrically insulation is essential for detecting activity of proteins or biomimetic carriers in the bilayer. This study provides insights for making better barriers on mesoporous support for carrier-mediated membrane separation process.
Porous silica nanoparticles (pSNPs) with pore sizes appropriate for biomolecule loading are potential for encapsulating dsRNA within the pores to achieve effective delivery of dsRNA to insects for RNA interference (RNAi). The mobility of dsRNA in the nanopores of the pSNPs is expected to have a functional effect on delivery of dsRNA to insects. The importance of pores to a mobile dsRNA network is demonstrated by the lack of measurable mobility for both lengths of RNA on nonporous materials. In addition, when the dsRNA could not penetrate the pores, dsRNA mobility is also not measurable at the surface of the particle. Thus, the pores seem to serve as a “sink” in providing a mobile network of dsRNA on the surface of the particle. This work successfully demonstrates the loading of RNA on functionalized pSNPs and identified factors that affects RNA loading and releasing, which provides basis for the delivery of RNA-loaded silica particles in vivo.
Bücher zum Thema "Catalyst carrier"
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National air carriers as catalysts for development: The case of Ethiopian Airlines (ET). Addis Ababa: Forum for Social Studies, 2006.
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inc, Catalyst, Hrsg. Advancing women in business--the Catalyst guide: Best practices from the corporate leaders. San Francisco: Jossey-Bass, 1998.
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Busacca, Maurizio, und Roberto Paladini. Collaboration Age. Venice: Fondazione Università Ca’ Foscari, 2020. http://dx.doi.org/10.30687/978-88-6969-424-0.
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Recently, public policies of urban regeneration have intensified and multiplied. They are being promoted with the aim to start social and economic dynamics within the local context which is subject to intervention. From the empirical analysis, we realise that such activities are mainly implemented by three subjects or by mixed coalitions (public institutions, actors of the third sector and companies). Within them, each player is moved by a multiplicity of interests and goals that go beyond their own nature – public interest, market and mutualism – and tend to redefine themselves, thus becoming hybrid forms of production of value (social, economic, cultural). By studying a number Italian and Catalan cases, this essay deals with the theory that, under specific conditions and configurations, a collaborative direction – of organization, production and design – would give life to successful procedures, even without the identification of a one-best-way. The collaboration is not simply a choice of operation, but a real production method which mobilises social resources to create hybrid solutions – between state, market and society – to complex issues that could not be faced solely with the use of the rationale of action of one among the three actors. In this framework, the systems of relations and interactions between players and shared capital become an essential condition for the success of every initiative of urban redevelopment, or failure thereof. Such initiatives are brought to life by the strategic role of individuals who foster connections as well as the dissemination of non-redundant information between social networks, and collective and individual actors which would otherwise be separated and barely able to communicate and collaborate with each other. In addition to the functions carried out by knowledge brokers, that have been extensively described in organisational studies and economic sociology, the aforementioned figures act as real social enzymes, that is to say, they handle the available information and function as catalysts of social processes of production of knowledge. Moreover, they increase the reaction speed, working on mechanisms which control the spontaneity.
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Bohringer, Bertram. Catalyst System Based on Spherical Activated Carbon As a Carrier and Use Thereof: United States Patent 9975109. Independently Published, 2020.
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Komarov, Vladimir. Adsorbents and carriers of catalysts. Scientific bases of regulation of porous structure. Infra-M Academic Publishing House, 2014. http://dx.doi.org/10.12737/2371.
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Садовников, Василий. Теория гетерогенного катализа. Теория хемосорбции. Publishing House Triumph, 2021. http://dx.doi.org/10.32986/978-5-40-10-01-2001.
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This monograph is a continuation of the monograph by V.V. Sadovnikov. Lateral interaction. Moscow 2006. Publishing house "Anta-Eco", 2006. ISBN 5-9730-0017-6. In this work, the foundations of the theory of heterogeneous catalysis and the theory of chemisorption are more easily formulated. The book consists of two parts, closely related to each other. These are the theoretical foundations of heterogeneous catalysis and chemisorption. In the theory of heterogeneous catalysis, an experiment is described in detail, which must be carried out in order to isolate the stages of a catalytic reaction, to find the stoichiometry of each of the stages. This experiment is based on the need to obtain the exact value of the specific surface area of the catalyst, the number of centers at which the reaction proceeds, and the output curves of each of the reaction products. The procedures for obtaining this data are described in detail. Equations are proposed and solved that allow calculating the kinetic parameters of the nonequilibrium stage and the thermodynamic parameters of the equilibrium stage. The description of the quantitative theory of chemisorption is based on the description of the motion of an atom along a crystal face. The axioms on which this mathematics should be based are formulated, the mathematical apparatus of the theory is written and the most detailed instructions on how to use it are presented. The first axiom: an atom, moving along the surface, is present only in places with minima of potential energy. The second axiom: the face of an atom is divided into cells, and the position of the atom on the surface of the face is set by one parameter: the cell number. The third axiom: the atom interacts with the surrounding material bodies only at the points of minimum potential energy. The fourth axiom: the solution of the equations is a map of the arrangement of atoms on the surface. The fifth axiom: quantitative equations are based on the concept of a statistically independent particle. The formation energies of these particles and their concentration are calculated by the developed program. The program based on these axioms allows you to simulate and calculate the interaction energies of atoms on any crystal face. The monograph is intended for students, post-graduate students and researchers studying work and working in petrochemistry and oil refining.
Buchteile zum Thema "Catalyst carrier"
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Duan, Lunbo, und Lin Li. „Oxygen Carrier Aided Gasification (OCAG)“. In Oxygen-Carrier-Aided Combustion Technology for Solid-Fuel Conversion in Fluidized Bed, 79–96. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-9127-1_5.
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AbstractGasification is regarded as an effective clean utilization technology of solid fuel, which can convert the chemical energy of solid fuel into gaseous fuel. However, the primary gas products contain not only the essential gas products, but also an unacceptable amount of tars, which will cause operational problems such as blockage of downstream equipment during gasification. Catalysts are often used after the gasifier to catalyze tar in the pyrolysis product gas. However, the activity ofcatalysts generally declines over time, as they will be poisoned by prolonged exposure to an atmosphere containing elements such as sulfur, chlorine and alkali metals. In addition, under the condition of high tar content, carbon deposition may form on the surface of catalyst, which leads to the deactivation of catalyst. The oxygen carrier particles of natural ores not only can transport oxygen, but also contain various metal elements that can be used as catalysts for tar cracking. Introduce the OCs to replace inert bed materials may not only provide a cheap catalyst for the technology, but also complete the transfer of oxygen between the two reactors, this process is oxygen carrier aided gasification (OCAG).
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Fujitani, Tadahiro, und Isao Nakamura. „Ruthenium Catalyst for Ammonia Decomposition“. In CO2 Free Ammonia as an Energy Carrier, 375–89. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-4767-4_24.
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Javaid, Rahat, Tetsuya Nanba und Hideyuki Matsumoto. „Kinetic Analysis of Ammonia Production on Ru Catalyst Under High Pressure Conditions“. In CO2 Free Ammonia as an Energy Carrier, 279–86. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-4767-4_18.
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Kubota, Jun. „Ammonia Synthesis from Nitrogen and Water Using an Electrochemical Hydrogen-Membrane Reactor, Ru Catalyst, and Phosphate Electrolytes“. In CO2 Free Ammonia as an Energy Carrier, 339–52. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-4767-4_22.
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Yang, Jian, Qingcai Liu, Mei Yang, Wenchang Xi und Wei Gao. „Preparation of SCR Catalyst Carrier by APCVD and Sol-gel Technologies“. In EPD Congress 2011, 391–97. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118495285.ch48.
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Duan, Lunbo, und Lin Li. „The Evolution of OCAC and Its Working Principles“. In Oxygen-Carrier-Aided Combustion Technology for Solid-Fuel Conversion in Fluidized Bed, 9–17. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-9127-1_2.
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AbstractThe technical route proposed by Thunman et al. to use OC to aid fluidized bed combustion is very creative, although it is likely that the OCAC technology was inspired by chemical looping combustion (CLC) technology developed at the same department of Chalmers University of Technology. OCAC shares many characteristics with CLC as well as with three-way catalyst (TWC) technology in terms of adopting the oxygen-carrying material, gas-solid redox reaction, improving fuel conversion and reducing pollutants, etc. Therefore, the principle and technical characteristics of TWC and CLC will be briefly reviewed here to provide some preliminary knowledge before introducing working principle of OCAC. In addition, the operation of reactor, reaction temperature, theperiod ofredox reaction, type of bed material and reaction products of the TWC, CLC and OCAC technologies are compared and analyzed comprehensively in the last part of this chapter.
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Zhang, Peng, Songzhe Chen, Laijun Wang und Ping Zhang. „Study on the High-Performance Catalyst for Sulfuric Acid Decomposition in the IS Cycle“. In Proceedings of the 10th Hydrogen Technology Convention, Volume 1, 370–82. Singapore: Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-99-8631-6_36.
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AbstractThe iodine-sulfur cycle coupled with a high-temperature gas-cooled reactor is a clean and efficient hydrogen production technology. The sulfuric acid decomposition reaction is the highest temperature process in the iodine-sulfur cycle, which requires 850 °C high temperature and catalyst to carry out at a high conversion rate. This study prepared a series of loaded sulfuric acid decomposition catalysts using anatase TiO2 and Ta2O5 as catalyst carriers and precious metal Pt as the active component. XRD, BET, and ICP-MS characterization of the catalysts demonstrated that the high calcination temperature could increase the crystallinity and content of the active components and decrease the specific surface area of the catalysts. The Pt/TiO2-850 catalyst showed good performance under different feed concentrations, reaction temperatures, and particle sizes. In addition, the scale-up production does not affect the Pt/TiO2-850 catalyst reaction performance. The Pt/TiO2-850 catalyst was tested in a bayonet-tube SiC reactor with a 100-h high throughput lifetime, which proved that the Pt/TiO2-850 catalyst has good stability.
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Buczek, B., S. Zięetek und A. Świątkowski. „Investigation of the Chromium-Copper-Silver Catalyst Distribution in the Porous Structure of Active Carbon Carrier Granules“. In The Kluwer International Series in Engineering and Computer Science, 117–22. Boston, MA: Springer US, 1996. http://dx.doi.org/10.1007/978-1-4613-1375-5_13.
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Ruckenstein, Eli, Hangquan Li und Chong Cheng. „Enzyme/Catalyst/Herbicide Carriers“. In Concentrated Emulsion Polymerization, 147–48. Boca Raton : Taylor & Francis, a CRC title, part of the Taylor & Francis imprint, a member of the Taylor & Francis Group, the academic division of T&F Informa, plc, 2018.: CRC Press, 2019. http://dx.doi.org/10.1201/9780429026577-14.
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Hosono, Hideo. „Electride Catalysts for Ammonia Synthesis“. In CO2 Free Ammonia as an Energy Carrier, 325–38. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-4767-4_21.
Der volle Inhalt der QuelleKonferenzberichte zum Thema "Catalyst carrier"
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Kawakami, Takashi, Tomiaki Furuya, Yukio Sasaki, Toshiyuki Yoshine, Yutaka Furuse und Mitsunobu Hoshino. „Feasibility Study on Honeycomb Ceramics for Catalytic Combustor“. In ASME 1989 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1989. http://dx.doi.org/10.1115/89-gt-41.
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This paper contains results of a structural feasibility study on honeycomb ceramic materials used for catalytic combustors in power gas turbines. Extruded cordierite honeycomb substrates are widely used as catalyst carriers in automotive exhaust systems, because of their excellent thermal shock resistance. For gas turbines, however, the ceramic catalyst carriers should retain the reliability at high temperature. In a hybrid catalytic combustor, which handles both catalysis and gas phases combustion, cordierite honeycomb structures (melt at 1445°C) can be adopted as the catalyst carrier, because the auxiliary gas phase combustion makes catalyst temperature lower than the conventional catalytic combustor. During this study, cordierite honeycomb (200 square cells/in2) tensile tests were carried out at high temperatures up to 1000°C. Using the finite element method, stresses in a cell wall were analyzed. The honeycomb cell wall mechanical strength was derived by comparing the experimental and analytical results. Also, combustor honeycomb cell stresses were calculated under typical oprerating conditions. Consequently, it was shown that it is sufficiently feasible to use the cordierite honeycomb structure as a catalyst carrier for hybrid catalytic combustors.
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Huang, Chih-Yung, Chun-Hung Lin, Chung-Yang Chou und Chin-Chia Su. „Experimental Studies of the Performance of a Small Reformer for Hydrogen Generation“. In ASME 2006 4th International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2006. http://dx.doi.org/10.1115/fuelcell2006-97045.
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This paper presents the experimental studies of the performance of a small reformer for hydrogen generation from water solution of methanol. An electric heater was built around the reactor unit to supply the energy for the endothermal reaction between methanol and steam. The parameters under studied were the temperature of the catalytic reaction (T), the mass flow rate of methanol solution (m˙), steam-to-methanol ratio (α), and the length (L) and number of cells (N) of the catalyst carrier, while the catalysts used were CuO-ZnO-Al2O3, CuO-ZnO-Al2O3-Pt-Rh, and Pt-Rh. The test results show that for all conditions both of the conversion and yield rates of hydrogen increase with increasing length and number of cells of the catalyst carrier. However, such increases become gradual in the high ranges of L and N. For the catalyst CuO-ZnO-Al2O3-Pt-Rh with N = 300 cells per square inch, L = 105mm, α = 1.9, and m˙ = 0.064 mole/min, the conversion rate may be as high as 99.9%. On the other hand, both of the conversion and yield rates decrease with increasing ratio of steam to methanol in the reactant. The decreases are more apparent at high temperature. When the mass flow rate of the methanol solution is increased, the conversion rate decreases. Such a decrease is more distinct in the medium range of methanol flow rate. On the other hand, the yield rate of hydrogen increases with the flow rate of methanol solution, especially at high temperature. For all of the three catalysts tested, both of the conversion and yield rates increase with reaction temperature, except for catalyst CuO-ZnO-Al2O3 at high temperature. Although catalyst CuO-ZnO-Al2O3-Pt-Rh shows no high-temperature deterioration, its performance is much poorer than that of catalyst CuO-ZnO-Al2O3 at low to medium temperatures. The difference in the performance between these two catalysts may be as high as 50%. By arranging a turbulence inducer located at the upstream side of the catalyst carrier, both of the conversion and yield rates can be increased significantly.
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Antonov, Andrey, Nikolay Samotaev, Grigory Tsarev, Andreas Tietz und Andrey Kirichenko. „Method for Platinum Group Metals Extraction from SiC Based Catalyst Carrier“. In 2019 IEEE International Conference on Electrical Engineering and Photonics (EExPolytech). IEEE, 2019. http://dx.doi.org/10.1109/eexpolytech.2019.8906798.
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Arias, Rebekah. „Image Analysis for SWNT Growth on Shutter Sputtered Catalyst“. In MME Undergraduate Research Symposium. Florida International University, 2022. http://dx.doi.org/10.25148/mmeurs.010568.
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Carbon Nanotubes (CNTs) have been used in remarkable ways since their discovery in 1991 by Sumio Iijima. Properties such as high thermal conductivity, good mechanical strength, and electrical conductivity are what make CNTs attractive. Some of their applications include water filtration, vehicles, energy storage, and now there is great potential in the biomedical field for CNTs as composites in tissue engineering, therapeutics carrier across the blood-brain barrier, cancer treatment, and much more. The issue that comes with Single-Walled Nanotubes (SWNTs) however is Ostwald ripening of catalyst and low CNT production. It is difficult to control gas parameters for hydrogen and argon and can be dangerous in a smaller lab, so acetylene without dilution gas is used. The method proposed here utilizes shutter sputtering of Iron on a th-SiO2/AlO substrate, followed by thermal chemical vapor deposition (CVD) for annealing. Shutter sputtering allows greater particle adhesion to the substrate due to wavelength and energy changes, allowing smaller catalysts to grow and a greater possibility of long SWNTs. We compare the effects of Ostwald ripening on catalysts formed onCarbon Nanotubes (CNTs) have been used in remarkable ways since their discovery in 1991 by Sumio Iijima. Properties such as high thermal conductivity, good mechanical strength, and electrical conductivity are what make CNTs attractive. Some of their applications include water filtration, vehicles, energy storage, and now there is great potential in the biomedical field for CNTs as composites in tissue engineering, therapeutics carrier across the blood-brain barrier, cancer treatment, and much more. The issue that comes with Single-Walled Nanotubes (SWNTs) however is Ostwald ripening of catalyst and low CNT production. It is difficult to control gas parameters for hydrogen and argon and can be dangerous in a smaller lab, so acetylene without dilution gas is used. The method proposed here utilizes shutter sputtering of Iron on a th-SiO2/AlO substrate, followed by thermal chemical vapor deposition (CVD) for annealing. Shutter sputtering allows greater particle adhesion to the substrate due to wavelength and energy changes, allowing smaller catalysts to grow and a greater possibility of long SWNTs. We compare the effects of Ostwald ripening on catalysts formed on a Fe shutter sputtered substrate annealed at 730°C and another at 760°C, in order to identify the correlation between the size and distance of catalyst particles for SWNT growths through Atomic Force Microscopy (AFM) image analysis. a Fe shutter sputtered substrate annealed at 730°C and another at 760°C, in order to identify the correlation between the size and distance of catalyst particles for SWNT growths through Atomic Force Microscopy (AFM) image analysis.
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Saleh, Mohamed E., Wei Li und Shi-chune Yao. „Mathematical Modeling of De-Hydrogenation Micro-Reactors for Vehicles Using the Liquid Carrier of Hydrogen Fuel“. In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-62304.
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When the organic liquid carrier of hydrogen is used as the fuel on a vehicle, a key component is the hydrogen releasing device, which requires large surface area of catalyst, small size and light weight. Micro-reactors with internal structure of micro pin-fin array is considered due to its high area-to-volume ratio and intimate impaction-contact with the fluids. To support the design of a first experiment, a mathematical model based on laws of conservation and chemical reaction is established. A surface-reaction efficiency has also been included to consider the possible effect of surface nonwetting in the hydrogen two-phase flow. This model has been demonstrated using the N-Ethyl Carbazole as the liquid carrier and Palladium as the catalyst. Due to the large gas generation rate, the numerical modeling indicates that the system operates at high void fraction with large slip ratio. This leads to an alternative system design of using segmented reactors with a hydrogen separator located in between. This leads to reduced size of the system and less catalyst material used.
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Ibrahim, Norliza, Amira Nadzirah Suhaidi und Nashrah Ayna Shah Fiesal. „Preparation of ceramic support for catalyst carrier from ceramic waste: Effect of sintering temperature“. In 3RD INTERNATIONAL SCIENCES, TECHNOLOGY & ENGINEERING CONFERENCE (ISTEC) 2018 - MATERIAL CHEMISTRY. Author(s), 2018. http://dx.doi.org/10.1063/1.5066965.
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Postnikov, B. V., und K. A. Lomanovich. „Heating internal channels of a catalyst carrier with periodic structure by impinging supersonic jet“. In PROCEEDINGS OF THE XXV CONFERENCE ON HIGH-ENERGY PROCESSES IN CONDENSED MATTER (HEPCM 2017): Dedicated to the 60th anniversary of the Khristianovich Institute of Theoretical and Applied Mechanics SB RAS. Author(s), 2017. http://dx.doi.org/10.1063/1.5007475.
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Avrutin, V., Ü. Özgür, N. Izyumskaya, S. Chevtchenko, J. Leach, J. C. Moore, A. A. Baski et al. „Carrier relaxation and stimulated emission in ZnO nanorods grown by catalyst-assisted vapor transport on various substrates“. In Integrated Optoelectronic Devices 2007, herausgegeben von Ferechteh Hosseini Teherani und Cole W. Litton. SPIE, 2007. http://dx.doi.org/10.1117/12.708835.
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Tang, Guangwu, Armin Silaen, Bin Wu, Chenn Q. Zhou, Dwight Agnello-Dean, Joseph Wilson, Qingjun Meng und Samir Khanna. „Numerical Simulation of an Industrial Fluid Catalytic Cracking Regenerator“. In ASME 2013 Heat Transfer Summer Conference collocated with the ASME 2013 7th International Conference on Energy Sustainability and the ASME 2013 11th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/ht2013-17527.
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Fluid catalytic cracking (FCC) is one of the most important conversion processes in petroleum refineries, and FCC regenerator is a key part of an FCC unit to recover the solid catalyst activity by burning off the deposited coke on the catalyst surface. In modern FCC units, regenerator is a cylindrical vessel. Carrier gas transports the solid catalyst from the stripper and feeds the catalyst into the regenerator through catalyst distributors. The catalyst is fluidized by the air that is injected into the regenerator through air rings in the bottom part of the cylindrical vessel. A three-dimensional multi-phase, multi-species reacting flow computational fluid dynamics (CFD) model was established to simulate the flow inside an FCC regenerator. The two phases involved in the flow are gas phase and solid phase. The Euler-Euler approach, where the two phases are considered to be continuous and fully inter-penetrating, is employed. The model includes gas-solid momentum exchange, gas-solid heat exchange, gas-solid mass exchange, and chemical reactions. Chemical reactions incorporated into the model simulate the combustion of coke which is present on the catalyst surface. The simulation results show a good agreement with plant data.
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Zhang, Hong-quan, Kai Zhang, Qing Zhang und Ai-dong Liu. „Technology Research on CH4 Sensor with Pd Catalyst using Supported Nano-material Carrier of γ-Al2O3-ZrO2-ThO2“. In 2018 IEEE 4th Information Technology and Mechatronics Engineering Conference (ITOEC). IEEE, 2018. http://dx.doi.org/10.1109/itoec.2018.8740571.
Der volle Inhalt der QuelleBerichte der Organisationen zum Thema "Catalyst carrier"
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Olsen. PR-179-10203-R01 Characterization of Oxidation Catalyst Performance - VOCs and Temperature Variation. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), Juni 2012. http://dx.doi.org/10.55274/r0010753.
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Oxidation catalysts are typically specified to reduce carbon monoxide (CO), Hazardous Air Pollutants (HAPs) and/or Volatile Organic Compounds (VOCs) from lean-burn engines. The application of catalysts to HAPs and VOC destruction is more recent, so greater effort has been placed on optimizing for CO oxidation than HAPs or VOC oxidation. In general, the catalysts consist of a porous, high surface area -alumina carrier material on a ceramic (typically cordierite) or stainless steel substrate. Although the alumina has some effectiveness in oxidation at high temperature, its primary role here is to provide a high surface area support for a well dispersed layer of platinum (Pt) and/or palladium (Pd) which provides numerous catalytic sites for oxidation activity. This work extends the current knowledge-base for application of oxidation catalysts in three areas: (1) species specific removal efficiencies, (2) temperature dependence, and (3) space velocity.
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Stepanenko, Sergey, Anton Koskin, Maria Alekseeva, Vasilii Kaichev und Vadim Yakovlev. Nickel-tin alloy catalysts for liquid organic hydrogen carrier dehydrogenation. Peeref, Juli 2023. http://dx.doi.org/10.54985/peeref.2307p6337630.
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Jensen, Craig, Daniel Brayton, Scott W. Jorgensen und Peter Hou. Development of a Practical Hydrogen Storage System Based on Liquid Organic Hydrogen Carriers and a Homogeneous Catalyst. Office of Scientific and Technical Information (OSTI), März 2017. http://dx.doi.org/10.2172/1347919.
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Tassitano, Jim, Daniel Olsen, Charles Mitchell und Bryan Willson. GRI-03-0083 NO2 Emissions from 2SC Large Bore Natural Gas Engines. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), Dezember 2018. http://dx.doi.org/10.55274/r0011537.
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NO2 emissions data from previous EECL projects on a large bore, slow speed, two-stroke lean burn engine is reanalyzed, looking at the effect of engine variables on the formation of NO2. Included are variations of operating conditions, fuel delivery, and ignition systems. By looking at the emission trends found in the data, techniques may be proposed for the reduction of NO2 emissions. An investigation into the effectiveness of catalysts on NO2 emissions is performed using data taken from previous testing on a medium bore, high speed, four-stroke lean burn engine. A summation of the current understanding of NO2 formation is also included. This is done through a thorough literature review. A chemical kinetics study was carried out through the use of the Chemkin 3.7 program suite. Kinetics simulations were performed to analyze EECL data and locate possible sources of NO2 in the engine.
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Asenath-Smith, Emily, Emma Ambrogi, Eftihia Barnes und Jonathon Brame. CuO enhances the photocatalytic activity of Fe₂O₃ through synergistic reactive oxygen species interactions. Engineer Research and Development Center (U.S.), September 2021. http://dx.doi.org/10.21079/11681/42131.
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Iron oxide (α-Fe₂O₃, hematite) colloids were synthesized under hydrothermal conditions and investigated as catalysts for the photodegradation of an organic dye under broad-spectrum illumination. To enhance photocatalytic performance, Fe₂O₃ was combined with other transition-metal oxide (TMO) colloids (e.g., CuO and ZnO), which are sensitive to different regions of the solar spectrum (far visible and ultraviolet, respectively), using a ternary blending approach for compositional mixtures. For a variety of ZnO/Fe₂O₃/CuO mole ratios, the pseudo-first-order rate constant for methyl orange degradation was at least double the sum of the individual Fe₂O₃ and CuO rate constants, indicating there is an underlying synergy governing the photocatalysis reaction with these combinations of TMOs. A full compositional study was carried out to map the interactions between the three TMOs. Additional experiments probed the identity and role of reactive oxygen species and elucidated the mechanism by which CuO enhanced Fe₂O₃ photodegradation while ZnO did not. The increased photocatalytic performance of Fe2O3 in the presence of CuO was associated with hydroxyl radical ROS, consistent with heterogeneous photo-Fenton mechanisms, which are not accessible by ZnO. These results imply that low-cost photocatalytic materials can be engineered for high performance under solar illumination by selective pairing of TMOs with compatible ROS.
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Handa, Avtar K., Yuval Eshdat, Avichai Perl, Bruce A. Watkins, Doron Holland und David Levy. Enhancing Quality Attributes of Potato and Tomato by Modifying and Controlling their Oxidative Stress Outcome. United States Department of Agriculture, Mai 2004. http://dx.doi.org/10.32747/2004.7586532.bard.
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General The final goal and overall objective of the current research has been to modify lipid hydroperoxidation in order to create desirable phenotypes in two important crops, potato and tomato, which normally are exposed to abiotic stress associated with such oxidation. The specific original objectives were: (i) the roles of lipoxygenase (LOX) and phospholipids hydroperoxide glutathione peroxidase (PHGPx) in regulating endogenous levels of lipid peroxidation in plant tissues; (ii) the effect of modified lipid peroxidation on fruit ripening, tuber quality, crop productivity and abiotic stress tolerance; (iii) the effect of simultaneous reduction of LOX and increase of PHGPx activities on fruit ripening and tuber quality; and (iv) the role of lipid peroxidation on expression of specific genes. We proposed to accomplish the research goal by genetic engineering of the metabolic activities of LOX and PHGPx using regulatable and tissue specific promoters, and study of the relationships between these two consecutive enzymes in the metabolism and catabolism of phospholipids hydroperoxides. USA Significant progress was made in accomplishing all objectives of proposed research. Due to inability to regenerate tomato plants after transforming with 35S-PHGPx chimeric gene construct, the role of low catalase induced oxidative stress instead of PHGPx was evaluated on agronomical performance of tomato plant and fruit quality attributes. Effects of polyamine, that protects DNA from oxidative stress, were also evaluated. The transgenic plants under expressing lipoxygenase (LOX-sup) were crossed with catalase antisense (CAT-anti) plants or polyamine over producing plants (SAM-over) and the lines homozygous for the two transgenes were selected. Agronomical performance of these line showed that low catalase induced oxidative stress negatively affected growth and development of tomato plants and resulted in a massive change in fruit gene expression. These effects of low catalase activity induced oxidative stress, including the massive shift in gene expression, were greatly overcome by the low lipoxygenase activity. Collectively results show that oxidative stress plays significant role in plant growth including the fruit growth. These results also for the first time indicated that a crosstalk between oxidative stress and lipoxygenase regulated processes determine the outcome during plant growth and development. Israel Regarding PHGPx, most of the study has concentrated on the first and the last specific objectives, since it became evident that plant transformation with this gene is not obvious. Following inability to achieve efficient transformation of potato and tomato using a variety of promoters, model plant systems (tobacco and potato cell cultures, tobacco calli and plantlets, and Arabidopsis) were used to establish the factors and to study the obstacles which prohibited the regeneration of plants carrying the genetic machinery for overproduction of PHGPx. Our results clearly demonstrate that while genetic transformation and over-expression of PHGPx occurs in pre-developmental tissue stage (cell culture, calli clusters) or in completed plant (Arabidopsis), it is likely that over-expression of this enzyme before tissue differentiation is leading to a halt of the regeneration process. To support this assumption, experiments, in which genetic engineering of a point-mutated PHGPx gene enable transformation and over-expression in plants of PhSPY modified in its catalytic site and thus inactive enzymatically, were successfully carried out. These combined results strongly suggest, that if in fact, like in animals and as we established in vitro, the plant PHGPx exhibits PH peroxidase activity, these peroxides are vital for the organisms developmental process.
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Greaney, Carrie, und Peter Bullemer. PR-624-173901-WEB Human Factors Risk of Pipeline Damage. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), März 2019. http://dx.doi.org/10.55274/r0011563.
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Thursday, April 11, 2019 PRESENTER: Peter Bullemer, Human Centered Solutions MODERATOR: Carrie Greaney, PRCI CLICK THE DOWNLOAD/BUY BUTTON TO ACCESS THE WEBINAR REGISTRATION LINK Webinar Description: The overall purpose of this project was to extend our understanding of the impact of human and organizational factors (HOF) on pipeline process safety incidents. Six pipeline incident reports were systematically analyzed using a two-phased approach developed in the Abnormal Situation Management (ASM�) Consortium research program. The first phase of the incident analysis approach used the TapRoot methodology to chart the event sequence, identify contributing factors, including organizational practice failures, and identifying root causes of the organizational practice failures. The second phase of the analysis characterized the organizational failures as Common Failure Modes based on the HCS Effective Operations Practices and the specific expression of the root causes in terms of Common Root Cause Manifestations based on the Dirty Dozen human factors taxonomy. The Dirty Dozen taxonomy of human factors was found to have the potential to provide a tractable root cause framework for human and organizational factors. Specific limitations of the Dirty Dozen taxonomy as a HOF framework are discussed. Learning Outcomes: � Understand the potential impact of human and organizational factors on pipeline process safety incidents. � Understand the potential applicability of a human factors classification framework, the Dirty Dozen, developed in the aviation maintenance industry to the pipeline industry. Expected Benefits: � Increased awareness of the potential role and impact of human and organizational factors within the pipeline industry � Catalyst for ideas on how to improve the incident reporting system within your organization to better characterize the impact of human and organizational factors. Target Audience: � Risk engineers � Pipeline design engineers � Pipeline construction, operations and maintenance management and personnel Related report: PR-624-173901-R01 Human Organizational Factors in Pipeline Incidents
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Or, Etti, David Galbraith und Anne Fennell. Exploring mechanisms involved in grape bud dormancy: Large-scale analysis of expression reprogramming following controlled dormancy induction and dormancy release. United States Department of Agriculture, Dezember 2002. http://dx.doi.org/10.32747/2002.7587232.bard.
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The timing of dormancy induction and release is very important to the economic production of table grape. Advances in manipulation of dormancy induction and dormancy release are dependent on the establishment of a comprehensive understanding of biological mechanisms involved in bud dormancy. To gain insight into these mechanisms we initiated the research that had two main objectives: A. Analyzing the expression profiles of large subsets of genes, following controlled dormancy induction and dormancy release, and assessing the role of known metabolic pathways, known regulatory genes and novel sequences involved in these processes B. Comparing expression profiles following the perception of various artificial as well as natural signals known to induce dormancy release, and searching for gene showing similar expression patterns, as candidates for further study of pathways having potential to play a central role in dormancy release. We first created targeted EST collections from V. vinifera and V. riparia mature buds. Clones were randomly selected from cDNA libraries prepared following controlled dormancy release and controlled dormancy induction and from respective controls. The entire collection (7920 vinifera and 1194 riparia clones) was sequenced and subjected to bioinformatics analysis, including clustering, annotations and GO classifications. PCR products from the entire collection were used for printing of cDNA microarrays. Bud tissue in general, and the dormant bud in particular, are under-represented within the grape EST database. Accordingly, 59% of the our vinifera EST collection, composed of 5516 unigenes, are not included within the current Vitis TIGR collection and about 22% of these transcripts bear no resemblance to any known plant transcript, corroborating the current need for our targeted EST collection and the bud specific cDNA array. Analysis of the V. riparia sequences yielded 814 unigenes, of which 140 are unique (keilin et al., manuscript, Appendix B). Results from computational expression profiling of the vinifera collection suggest that oxidative stress, calcium signaling, intracellular vesicle trafficking and anaerobic mode of carbohydrate metabolism play a role in the regulation and execution of grape-bud dormancy release. A comprehensive analysis confirmed the induction of transcription from several calcium–signaling related genes following HC treatment, and detected an inhibiting effect of calcium channel blocker and calcium chelator on HC-induced and chilling-induced bud break. It also detected the existence of HC-induced and calcium dependent protein phosphorylation activity. These data suggest, for the first time, that calcium signaling is involved in the mechanism of dormancy release (Pang et al., in preparation). We compared the effects of heat shock (HS) to those detected in buds following HC application and found that HS lead to earlier and higher bud break. We also demonstrated similar temporary reduction in catalase expression and temporary induction of ascorbate peroxidase, glutathione reductase, thioredoxin and glutathione S transferase expression following both treatments. These findings further support the assumption that temporary oxidative stress is part of the mechanism leading to bud break. The temporary induction of sucrose syntase, pyruvate decarboxylase and alcohol dehydrogenase indicate that temporary respiratory stress is developed and suggest that mitochondrial function may be of central importance for that mechanism. These finding, suggesting triggering of identical mechanisms by HS and HC, justified the comparison of expression profiles of HC and HS treated buds, as a tool for the identification of pathways with a central role in dormancy release (Halaly et al., in preparation). RNA samples from buds treated with HS, HC and water were hybridized with the cDNA arrays in an interconnected loop design. Differentially expressed genes from the were selected using R-language package from Bioconductor project called LIMMA and clones showing a significant change following both HS and HC treatments, compared to control, were selected for further analysis. A total of 1541 clones show significant induction, of which 37% have no hit or unknown function and the rest represent 661 genes with identified function. Similarly, out of 1452 clones showing significant reduction, only 53% of the clones have identified function and they represent 573 genes. The 661 induced genes are involved in 445 different molecular functions. About 90% of those functions were classified to 20 categories based on careful survey of the literature. Among other things, it appears that carbohydrate metabolism and mitochondrial function may be of central importance in the mechanism of dormancy release and studies in this direction are ongoing. Analysis of the reduced function is ongoing (Appendix A). A second set of hybridizations was carried out with RNA samples from buds exposed to short photoperiod, leading to induction of bud dormancy, and long photoperiod treatment, as control. Analysis indicated that 42 genes were significant difference between LD and SD and 11 of these were unique.