Academic literature on the topic 'Urea'

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Journal articles on the topic "Urea"

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Heimer, Susan R., and Harry L. T. Mobley. "Interaction of Proteus mirabilis Urease Apoenzyme and Accessory Proteins Identified with Yeast Two-Hybrid Technology." Journal of Bacteriology 183, no. 4 (2001): 1423–33. http://dx.doi.org/10.1128/jb.183.4.1423-1433.2001.

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ABSTRACT Proteus mirabilis, a gram-negative bacterium associated with complicated urinary tract infections, produces a metalloenzyme urease which hydrolyzes urea to ammonia and carbon dioxide. The apourease is comprised of three structural subunits, UreA, UreB, and UreC, assembled as a homotrimer of individual UreABC heterotrimers (UreABC)3. To become catalytically active, apourease acquires divalent nickel ions through a poorly understood process involving four accessory proteins, UreD, UreE, UreF, and UreG. While homologues of UreD, UreF, and UreG have been copurified with apourease, it rema
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Voland, Petra, David L. Weeks, Elizabeth A. Marcus, Christian Prinz, George Sachs, and David Scott. "Interactions among the sevenHelicobacter pyloriproteins encoded by the urease gene cluster." American Journal of Physiology-Gastrointestinal and Liver Physiology 284, no. 1 (2003): G96—G106. http://dx.doi.org/10.1152/ajpgi.00160.2002.

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Survival of Helicobacter pylori in acid depends on intrabacterial urease. This urease is a Ni2+-containing oligomeric heterodimer. Regulation of its activity and assembly is important for gastric habitation by this neutralophile. The gene complex encodes catalytic subunits ( ureA/B), an acid-gated urea channel ( ureI), and accessory assembly proteins ( ureE–H). With the use of yeast two-hybrid analysis for determining protein-protein interactions, UreF as bait identified four interacting sequences encoding UreH, whereas UreG as bait detected five UreE sequences. These results were confirmed by
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Sangari, Félix J., Asunción Seoane, María Cruz Rodríguez, Jesús Agüero, and Juan M. García Lobo. "Characterization of the Urease Operon of Brucella abortus and Assessment of Its Role in Virulence of the Bacterium." Infection and Immunity 75, no. 2 (2006): 774–80. http://dx.doi.org/10.1128/iai.01244-06.

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ABSTRACT Most members of the genus Brucella show strong urease activity. However, the role of this enzyme in the pathogenesis of Brucella infections is poorly understood. We isolated several Tn5 insertion mutants deficient in urease activity from Brucella abortus strain 2308. The mutations of most of these mutants mapped to a 5.7-kbp DNA region essential for urease activity. Sequencing of this region, designated ure1, revealed the presence of seven open reading frames corresponding to the urease structural proteins (UreA, UreB, and UreC) and the accessory proteins (UreD, UreE, UreF, and UreG).
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Lisnyak, Yu. V., and AV Martynov. "STRUCTURAL ORGANIZATION OF BACTERIAL UREASES." Annals of Mechnikov Institute, no. 3 (November 18, 2016): 22–30. https://doi.org/10.5281/zenodo.167426.

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This brief review concerns the basic principles of structural organization of multi-subunit bacterial ureases and formation of their quaternary structure. Urease is a nickel-containing enzyme (urea amidohydrolase, ЕС 3.5.1.5) that catalyses the hydrolysis of urea to get ammonia and carbamate which then decomposes with water to get ammonia and carbon dioxide. Urease is produced by bacteria, fungi, yeast and plants. On the basis of similarities in amino acid sequences, ureases assumed to have a similar structure and conservative catalytic mechanism. Within past two decades bacterial ureases have
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Yuen, Man Hon, Yu Hang Fong, Yap Shing Nim, Pak Ho Lau, and Kam-Bo Wong. "Structural insights into how GTP-dependent conformational changes in a metallochaperone UreG facilitate urease maturation." Proceedings of the National Academy of Sciences 114, no. 51 (2017): E10890—E10898. http://dx.doi.org/10.1073/pnas.1712658114.

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The ability of metallochaperones to allosterically regulate the binding/release of metal ions and to switch protein-binding partners along the metal delivery pathway is essential to the metallation of the metalloenzymes. Urease, catalyzing the hydrolysis of urea into ammonia and carbon dioxide, contains two nickel ions bound by a carbamylated lysine in its active site. Delivery of nickel ions for urease maturation is dependent on GTP hydrolysis and is assisted by four urease accessory proteins UreE, UreF, UreG, and UreH(UreD). Here, we determined the crystal structure of the UreG dimer from Kl
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Scott, David R., Elizabeth A. Marcus, Yi Wen, Siddarth Singh, Jing Feng, and George Sachs. "Cytoplasmic Histidine Kinase (HP0244)-Regulated Assembly of Urease with UreI, a Channel for Urea and Its Metabolites, CO2, NH3, and NH4+, Is Necessary for Acid Survival of Helicobacter pylori." Journal of Bacteriology 192, no. 1 (2009): 94–103. http://dx.doi.org/10.1128/jb.00848-09.

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ABSTRACT Helicobacter pylori colonizes the normal human stomach by maintaining both periplasmic and cytoplasmic pH close to neutral in the presence of gastric acidity. Urease activity, urea flux through the pH-gated urea channel, UreI, and periplasmic α-carbonic anhydrase are essential for colonization. Exposure to pH 4.5 for up to 180 min activates total bacterial urease threefold. Within 30 min at pH 4.5, the urease structural subunits, UreA and UreB, and the Ni2+ insertion protein, UreE, are recruited to UreI at the inner membrane. Formation of this complex and urease activation depend on e
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Kasatkina, Svetlana O., Kirill K. Geyl, Sergey V. Baykov, Mikhail S. Novikov, and Vadim P. Boyarskiy. "“Urea to Urea” Approach: Access to Unsymmetrical Ureas Bearing Pyridyl Substituents." Advanced Synthesis & Catalysis 364, no. 7 (2022): 1295–304. http://dx.doi.org/10.1002/adsc.202101490.

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Masepohl, Bernd, Björn Kaiser, Nazila Isakovic, Cynthia L. Richard, Robert G. Kranz, and Werner Klipp. "Urea Utilization in the Phototrophic BacteriumRhodobacter capsulatus Is Regulated by the Transcriptional Activator NtrC." Journal of Bacteriology 183, no. 2 (2001): 637–43. http://dx.doi.org/10.1128/jb.183.2.637-643.2001.

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ABSTRACT The phototrophic nonsulfur purple bacteriumRhodobacter capsulatus can use urea as a sole source of nitrogen. Three transposon Tn5-induced mutations (Xan-9, Xan-10, and Xan-19), which led to a Ure−phenotype, were mapped to the ureF and ureCgenes, whereas two other Tn5 insertions (Xan-20 and Xan-22) were located within the ntrC and ntrB genes, respectively. As in Klebsiella aerogenes and other bacteria, the genes encoding urease (ureABC) and the genes required for assembly of the nickel metallocenter (ureD andureEFG) are clustered in R. capsulatus(ureDABC-orf136-ureEFG). No homologues o
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Wen, Yi, Jing Feng, David R. Scott, Elizabeth A. Marcus, and George Sachs. "The pH-Responsive Regulon of HP0244 (FlgS), the Cytoplasmic Histidine Kinase of Helicobacter pylori." Journal of Bacteriology 191, no. 2 (2008): 449–60. http://dx.doi.org/10.1128/jb.01219-08.

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ABSTRACT Helicobacter pylori colonizes the acidic gastric environment, in contrast to all other neutralophiles, whose acid resistance and tolerance responses allow only gastric transit. This acid adaptation is dependent on regulation of gene expression in response to pH changes in the periplasm and cytoplasm. The cytoplasmic histidine kinase, HP0244, which until now was thought only to regulate flagellar gene expression via its cognate response regulator, HP0703, was found to generate a response to declining medium pH. Although not required for survival at pH 4.5, HP0244 is required for surviv
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Abdulrahman, Alia Talaat, Shna Ibrahim Ismail, Salar Saadi Hussain, Najat Jabbar Ahmed, and Ahmed Nawzad Hassan. "Detection of Helicobacter Pylori’s Virulence Gene (UreA) and its Influence on the Result of Rapid Urease Test (RUT)." Al-Mustansiriyah Journal of Science 33, no. 4 (2022): 42–48. http://dx.doi.org/10.23851/mjs.v33i4.1152.

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UreA is an important virulence factor of Helicobacter pylori that, along with UreB and UreC, produces urease. Urease enzyme helps the bacterium to colonize the human stomach through metabolizing urea in order to neutralize the gastric environment. The current study aimed to detect the prevalence of the H. pylori’s ureA virulence factor gene, and to investigate the influence of this gene on the result of the rapid urease test (RUT). Eighty stomach biopsy samples were isolated from participants who were suspected to be infected with H. pylori in Erbil city. Participants were 36 males and 44 fema
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Dissertations / Theses on the topic "Urea"

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Gray, Lawrence Robert. "Detailed characterization of the urea channel urei from helicobacter pylori." Diss., University of Iowa, 2012. https://ir.uiowa.edu/etd/3306.

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HpUreI is a pH-gated urea channel found in the pathogenic bacterium Helicobacter pylori. This protein is an essential component of the mechanism of acid acclimation, which allows Helicobacter pylori to survive in the acidic conditions of the stomach. HpUreI conducts urea into the cytoplasm, where it is hydrolyzed by urease into carbon dioxide and ammonia. These products then transit back into the periplasm, where they function as a buffer and proton consumer respectively. HpUreI is an attractive target for small molecule inhibitors for the treatment of H. pylori infections as mutant strains la
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Gasparelli, Everton Rogério Ferraz [UNESP]. "Determinação da atividade sérica de enzimas hepáticas e da concentração de uréia, creatinina, cortisol, imunoglobulina G dos valores hemogasométricos de bezerros da raça Nelore oriundos de fertilização in vivo (FV) e fertilização in vitro (FIV)." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/92203.

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Made available in DSpace on 2014-06-11T19:25:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-08-28Bitstream added on 2014-06-13T19:53:40Z : No. of bitstreams: 1 gasparelli_erf_me_araca.pdf: 500187 bytes, checksum: 20384c22730ccd6e17828305c437e923 (MD5)<br>Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)<br>Foram acompanhados 310 parturições de receptoras, com embriões fertilizados in vivo (FV) e in vitro (FIV) da raça Nelore, para determinar os índices de partos distócicos em receptoras meio sangue das raças Braford/Nelore, Hereford/Nelore, Simental/Nelore, Red Angus/N
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Gasparelli, Everton Rogério Ferraz. "Determinação da atividade sérica de enzimas hepáticas e da concentração de uréia, creatinina, cortisol, imunoglobulina G dos valores hemogasométricos de bezerros da raça Nelore oriundos de fertilização in vivo (FV) e fertilização in vitro (FIV) /." Araçatuba : [s.n.], 2007. http://hdl.handle.net/11449/92203.

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Orientador: Francisco Leydson Formiga Feitosa<br>Banca: Alice Maria Melville Paiva Della Libera<br>Banca: José Jurandir Agliari<br>Resumo: Foram acompanhados 310 parturições de receptoras, com embriões fertilizados in vivo (FV) e in vitro (FIV) da raça Nelore, para determinar os índices de partos distócicos em receptoras meio sangue das raças Braford/Nelore, Hereford/Nelore, Simental/Nelore, Red Angus/Nelore, Nelore e anelorados, com idade entre três e seis anos, assim como avaliar o estado de saúde dos bezerros obtidos por intermédio de transferência de embriões, resultantes das técnicas de f
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Wiebler, James. "UREA HYDROLYSIS BY GUT BACTERIA: FIRST EVIDENCE FOR UREA-NITROGEN RECYCLING IN AMPHIBIA." Miami University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=miami152535331130121.

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Toledo, Paulo Roberto Aparecido Bueno de [UNESP]. "Desenvolvimento de metodologia analítica ambientalmente mais amigável para a determinação de ureía em matrizes diversas." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/110844.

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Made available in DSpace on 2014-12-02T11:16:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-01-16Bitstream added on 2014-12-02T11:21:05Z : No. of bitstreams: 1 000748438_20160205.pdf: 244315 bytes, checksum: b3a80e273d6ebb287ceaa49a960f426c (MD5) Bitstreams deleted on 2016-02-05T13:56:07Z: 000748438_20160205.pdf,. Added 1 bitstream(s) on 2016-02-05T13:56:45Z : No. of bitstreams: 1 000748438.pdf: 1943082 bytes, checksum: 36b51511eac9620010a260579954477b (MD5)<br>Os princípios da Química Verde têm norteado o desenvolvimento de novos procedimentos analíticos que visam reduzir a u
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Toledo, Paulo Roberto Aparecido Bueno de. "Desenvolvimento de metodologia analítica ambientalmente mais amigável para a determinação de ureía em matrizes diversas /." Araraquara, 2014. http://hdl.handle.net/11449/110844.

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Orientador: Leonardo Pezza<br>Co-orientador: Helena Redigolo Pezza<br>Banca: Edilene Cristina Ferreira<br>Banca: Matthieu Tubino<br>Resumo: Os princípios da Química Verde têm norteado o desenvolvimento de novos procedimentos analíticos que visam reduzir a utilização de substâncias tóxicas e a produção de resíduos que necessitam de tratamento de custo elevado e profissional treinado13. Com base nesses princípios, o presente trabalho propõe o desenvolvimento de uma metodologia ambientalmente mais amigável que possa ser aplicada à análise de ureia em leite e cosméticos.·. A ureia é usada em inúme
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Lemos, Evandro Freire. "Uso de fertilizante nitrogenado de liberação lenta na cultura do milho em sistema plantio direto." Universidade Jose do Rosario Vellano, 2011. http://tede2.unifenas.br:8080/jspui/handle/jspui/58.

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Made available in DSpace on 2016-05-02T13:54:18Z (GMT). No. of bitstreams: 1 EvandroFreireLemos-dissertacao.pdf: 149475 bytes, checksum: 157cfab2d31ed366f87b82fe037eb10e (MD5) Previous issue date: 2011-06-14<br>The adoption of best practices for use of fertilizers has contributed to the reduction in nutrient losses and the use of protected sources of nitrogen appears to be an interesting alternative.The aim of this study was a technical and economic evaluation of the effects of different nitrogen using slow release urea compared with traditional use of urea. The experimental design was rando
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Günther, Ulrike, Marcus Hartmann, Siegfried Wartewig, and Reinhard Neubert. "Diffusion of urea through membranes." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-194383.

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Günther, Ulrike, Marcus Hartmann, Siegfried Wartewig, and Reinhard Neubert. "Diffusion of urea through membranes." Diffusion fundamentals 4 (2006) 4, S. 1-5, 2006. https://ul.qucosa.de/id/qucosa%3A14277.

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Park, Yong Hun. "An investigation of urea decomposition and selective non-catalytic removal of nitric oxide with urea." Texas A&M University, 2004. http://hdl.handle.net/1969.1/279.

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The use of urea (NH2CONH2) to remove nitric oxide (NO) from exhaust streams was investigated using a laboratory laminar-flow reactor. The experiments used a number of gas compositions to simulate different combustion exhaust gases. The urea was injected into the gases as a urea-water solution. The decomposition processes of the urea-water solutions and urea powder were examined. For both the nitric oxide removal and the urea decomposition experiments, a Fourier transform infrared (FTIR) spectrometer was used to determine the concentrations of the product species. The products from the decompos
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Books on the topic "Urea"

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Canada. Environmental Protection Programs Directorate. Technical Services Branch., ed. Urea. Environmental Protection Service, 1985.

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Yang, Baoxue, and Jeff M. Sands, eds. Urea Transporters. Springer Netherlands, 2014. http://dx.doi.org/10.1007/978-94-017-9343-8.

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Yahya, Noorhana. Green Urea. Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-10-7578-0.

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Yang, Baoxue, and Jeff M. Sands, eds. Urea Transporters. Springer Nature Singapore, 2025. https://doi.org/10.1007/978-981-96-6898-4.

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Ritchie, Mark. Biosensors for urea and aspartame. UMIST, 1996.

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Canada Mortgage and Housing Corporation., ed. Urea-formaldehyde foam insulaton (UFFI). Canada Mortgage and Housing Corporation, 2001.

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Massachusetts. Department of Public Health. UFFI (Urea Formaldehyde Foam Insulation). Massachusetts Dept. of Public Health, 1987.

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United States International Trade Commission. Urea from the German Democratic Republic, Romania, and the Union of Soviet Socialist Republics: Determinations of the Commission in investigations nos. 731-TA-338 through 340 (final) under the Tariff Act of 1930, together with the information obtained in the investigations. U.S. International Trade Commission, 1987.

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Stuart, Tiernan. Analytical studies into the crease resistant finishing of linen with a bifunctional urea-formaldehyde reagent, dimethylol ethylene urea. The Author], 1999.

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Ahmad, Naseem, and Mohammad Faisal, eds. Thidiazuron: From Urea Derivative to Plant Growth Regulator. Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-10-8004-3.

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Book chapters on the topic "Urea"

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Bährle-Rapp, Marina. "Urea." In Springer Lexikon Kosmetik und Körperpflege. Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_10898.

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Miyakawa, Shin, and Didier Despois. "Urea." In Encyclopedia of Astrobiology. Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-11274-4_1634.

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Wang, Hongkai, Jianhua Ran, and Tao Jiang. "Urea." In Subcellular Biochemistry. Springer Netherlands, 2014. http://dx.doi.org/10.1007/978-94-017-9343-8_2.

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Hignett, Travis P. "Urea." In Fertilizer Manual. Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-017-1538-6_9.

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Gooch, Jan W. "Urea." In Encyclopedic Dictionary of Polymers. Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-6247-8_12387.

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Miyakawa, Shin, and Didier Despois. "Urea." In Encyclopedia of Astrobiology. Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-44185-5_1634.

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Miyakawa, Shin, and Didier Despois. "Urea." In Encyclopedia of Astrobiology. Springer Berlin Heidelberg, 2023. http://dx.doi.org/10.1007/978-3-662-65093-6_1634.

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Miyakawa, Shin, and Didier Despois. "Urea." In Encyclopedia of Astrobiology. Springer Berlin Heidelberg, 2022. http://dx.doi.org/10.1007/978-3-642-27833-4_1634-4.

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Miyakawa, Shin, and Didier Despois. "Urea." In Encyclopedia of Astrobiology. Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-27833-4_1634-3.

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Yahya, Noorhana. "Urea Fertilizer: The Global Challenges and Their Impact to Our Sustainability." In Green Urea. Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-10-7578-0_1.

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Conference papers on the topic "Urea"

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Dubin, Leonard, and Daniel V. Diep. "Scale Control in Urea Solutions." In CORROSION 1997. NACE International, 1997. https://doi.org/10.5006/c1997-97173.

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Abstract Legislation to control NOx emissions, one cause of acid rain and ozone induced smog, has created an impetus to control NOx emissions. Selective Non Catalytic Reduction (SNCR) using urea chemistry is utilized to control NOx emissions from boilers, municipal waste incinerators, refinery furnaces, recovery boilers, utilities and other stationary combustion sources. Control requires injecting urea-based solutions into the flue gas at specified temperatures. Urea solutions accelerate CaCO3 precipitation in industrial waters used for dilution, and thereby interfere with proper application o
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Lopes, Diego C., and Mois�s Teles dos Santos. "A two-level model to assess the economic feasibility of renewable urea production from agricultural waste." In The 35th European Symposium on Computer Aided Process Engineering. PSE Press, 2025. https://doi.org/10.69997/sct.166762.

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This work proposes a two-level model, combining process and supply chain models, and an optimization framework for an integrated biorefinery system to convert agricultural residues into renewable urea via gasification routes. The process model of the gasification, ammonia and urea synthesis was developed in Aspen Plus� to identify key performance indicators such as energy consumption and relative yields for urea for different biomasses and operating conditions; then, these key process data were used in a mixed-integer linear programming (MILP) model, designed to identify the optimal combinatio
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Gullberg, Daniel, Robert Mattsson, and Josefin Eidhagen. "New Duplex Stainless Steel Optimized for the Urea Process." In CORROSION 2018. NACE International, 2018. https://doi.org/10.5006/c2018-11459.

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Abstract Corrosion of stainless steels is a known problem in the high-pressure section of urea plants. A particularly demanding part of the plant, which often has the highest passive corrosion rates, is the high-pressure stripper. The reason is that the corrosion is strongly temperature dependent. This paper presents the development program of UNS S83071, a new improved duplex stainless steel customized for this environment. The key for the successful development was alloy screening in ammonium carbamate solution corresponding to stripper conditions. It was shown that there is a clear differen
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Thanawala, Karan, Anand S. Khanna, and R. K. Singh Raman. "Development of Self-Healing Coatings Using Encapsulated Linseed Oil and Tung Oil as Healing Agents." In CORROSION 2016. NACE International, 2016. https://doi.org/10.5006/c2016-07310.

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Abstract Encapsulation of Linseed Oil and Tung Oil in urea-formaldehyde shells was performed using in-situ polymerization technique. Optimization of process parameters for preparation of microcapsules were carried out using calculated amounts of oil and urea-formaldehyde, that were subjected to formation of spherical microcapsules of 25-45 μm size, that depend on the reaction time and stirring speed. The microcapsules thus prepared were analyzed using optical microscopy (OM), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR), for ensuring the encapsulation
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Kadu, Sachin, and Harish gangwar. "Urea Quality Sensor Integration in Urea Supply Line / Urea Tank." In SAE 2012 World Congress & Exhibition. SAE International, 2012. http://dx.doi.org/10.4271/2012-01-1086.

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Bose, Asmita, and Karabi Biswas. "Digital Urea Meter for Impedeometric Urea Sensor." In 2019 IEEE International Instrumentation and Measurement Technology Conference (I2MTC). IEEE, 2019. http://dx.doi.org/10.1109/i2mtc.2019.8826918.

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Vicar, Nicoleta, Adina Berbecea, Alina Lato, Liliana Brei, and Isidora Raduloiv. "INFLUENCE OF COATED UREA APPLICATION ON SOIL ORGANIC CARBON SEQUESTRATION." In 23rd SGEM International Multidisciplinary Scientific GeoConference 2023. STEF92 Technology, 2023. http://dx.doi.org/10.5593/sgem2023v/4.2/s19.31.

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The application of nitrogen fertilizers in the form of urea tends to increase acidity, especially on low pH soils, and as a result can lead to increased aluminum toxicity, which can adversely affect not only soil properties such as microbial activity, but also productivity. Application of different types of urea with inhibitors to reduce nitrogen losses would result in a different carbon response to fertilizers applications for the same soil type because of differences in soil micro-environment, including microbial biomass and activity. The aim of the study was to determine the influence of ap
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Ganne, Rajakumar, Kaushal K. Jain, Peter H. Meckl, Harshil Angre, and Jagdish R. Hiremath. "Computationally Efficient Urea-Dosing Controllers for Urea-SCR." In ASME 2020 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/dscc2020-3213.

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Abstract This paper presents two non-model-based reference-shaping and a model-based predictive urea-dosing controller for the Urea-SCR system. An ideal urea-dosing controller would minimize both tailpipe NOx and NH3 slip. However, this is not possible because of the trade-off between deNOx and NH3 slip. This trade-off is used to clearly define a control objective in terms of NH3 slip. Three controllers are then developed to meet this control objective such that they are all computationally inexpensive. The three controllers are then tested for three very different drive cycles. Simulation res
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Rosker, Mark J. "Recent Developments In Urea." In 30th Annual Technical Symposium, edited by Larry G. DeShazer. SPIE, 1987. http://dx.doi.org/10.1117/12.939611.

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Jamilova, N. Q., and T. R. Dusiyorov. "UREA FURFUROL RESIN SYNTHESIS." In Теоретические и практические вопросы химической науки и технологий. Восточно-Сибирский государственный университет технологий и управления, 2022. http://dx.doi.org/10.53980/9785907599543_157.

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Reports on the topic "Urea"

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Chaiyabutr, Narongsak, Somchai Chanpongsang, and Prapa Loypetjra. Studies on urea metabolism in swamp buffaloes given exogenous urea infusion. Chulalongkorn University, 1990. https://doi.org/10.58837/chula.res.1990.30.

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Five female swamp buffaloes, weighing between 200-290 Kg, were used in the experiment. The experiment was conducted into two series. The first series was performed as control. In The second series, the animal was given an exogenous urea infusion. The turnover of plasma and quantitative aspect of urea recycle were investigated in both series using [supscript 14] C-urea. The results of experiments showed that the concentration of plasma urea increased significantly during exogenous urea infusion. Urea space increased from 85 L to 92 L. Turnover rate of urea decreased while the biological half li
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Chaiyabutr, Narongsak, Chollada Buranakarl, Prapa Loypetjra, and Ayus Pichaicharnarong. Effect of exogenous urea on urea metabolism in heat stressed swamp buffalo. Chulalongkorn University, 1987. https://doi.org/10.58837/chula.res.1987.33.

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Effect of exogenous urea on urea metabolism in heat stressed swamp buffalo.In buffaloes during normal ambient temperature given exogenous urea infusion intravenously; the heart rate, respiratory rate, packed cell volume, glomerular filtration rate, plasma concentration of electrolyte, protein and creatinine were not significantly affected. The rate of urine flow, fractional urea excretion, urinary potassium excretion and osmolar clearance significantly decreased on the third hour of urea infusion. The decrease of fractional potassium excretion was concomitant with the reduction of the reductio
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Rossiter, Walter J. Urea-formaldehyde foam insulations :. National Bureau of Standards, 1985. http://dx.doi.org/10.6028/nbs.tn.1210.

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Chaiyabutr, Narongsak, Chollada Buranakarl, and Prapa Loypetjra. Effects of exogenous urea infusion on glucose metabolism in acute heat stressed swamp buffaloes. Chulalongkorn University, 1988. https://doi.org/10.58837/chula.res.1988.43.

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Effects of exogenous urea infusion on glucose metabolism in acute heat stressed swamp buffaloes. Five buffaloes kept in normal ambient temperature showed no significant changes in the heart rate, respiratory rate, packed cell volume, glucose turnover rate, glucose pool size, glucose clearance, glomerular filtration rate (GFR), effective renal plasma flow (ERPF), plasma concentration of electrolytes, protein and creatinine during intravenous infusion of urea for 4 h. The rate of urine flow, fractional urea excretion, urinary potassium excretion and osmolar clearance significantly decreased on t
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Strey, Daniel J., and Nick E. Christians. Comparison of Polymer-coated Urea Fertilizers. Iowa State University, Digital Repository, 2014. http://dx.doi.org/10.31274/farmprogressreports-180814-883.

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Ah Mew, Nicholas, Robert McCarter, Rima Izem, et al. Comparing Treatment Options for Urea Cycle Disorders. Patient-Centered Outcomes Research Institute (PCORI), 2020. http://dx.doi.org/10.25302/12.20.cer.150227816.

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ลาวัณย์ประเสริฐ, สมทรง, พรพิมล กิจสนาโยธิน, นวลศรี นิวัติศัยวงศ์, มยุรี ตันติสิระ та ชำนาญ ภัตรพานิช. ผลของ N- (2-propylpentanoyl) urea ต่อเอนไซม์ที่ใช้ในเมแทบอลิซึมยาหรือสารในตับหนูขาว : รายงานผลการวิจัย. จุฬาลงกรณ์มหาวิทยาลัย, 1999. https://doi.org/10.58837/chula.res.1999.26.

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ศึกษาผลของ เอ็น-(2-โพรพิลเพนตาโนอิล) ยูเรีย (วีพียู) ต่อเอ็นไซม์ที่ใช้ในเมแทบอลิซึมของยาหรือสารในตับหนูขาว โดยการฉีดวีพียู และวัลโปรอิค แอซิด (วีพีเอ) ในขนาดที่ต้านชักได้ในสัตว์ทดลองจำนวนครึ่งหนึ่ง แก่หนูขาวเพศผู้ ทางหน้าท้อง เป็นเวลา 7 วัน หลังจากนั้นฆ่าหนูโดยวิธีดึงคอ แล้วเตรียมไมโครโซม และไซโตซอล จากตับ ทำการวิเคราะห์หาปริมาณไซโตโครมพี 450 รวม และแอคติวิตีของไซโตโครมพี 450 จากไมโครโซม แอคติวิตีของกลูตาไทโอน เอส-ทรานสเฟอเรส จากไซโตซอล และปริมาณกลูตาไทโอนรวมจากตับ ผลการวิจัยพบว่า ทั้งวีพียูและวีพีเอไม่มีผลเปลี่ยนแปลงค่าต่างๆเหล่านี้ : ปริมาณไซโตโครมพี 450 รวม แอคติวิตีของเอทอซิ-และ เมทอซิรีโซ
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TRUONG, THANH-TAM. TWO-STEP SYNTHESIS OF POLY (UREA FORMALDEHYDE) MICROCAPSULES. Office of Scientific and Technical Information (OSTI), 2022. http://dx.doi.org/10.2172/1878530.

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Yeo, Yukyung. Urea crisis sparks South Korean supply chain revamp. East Asia Forum, 2024. http://dx.doi.org/10.59425/eabc.1724407200.

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Glass, Robert, and Anh Nguyen-Huu. Urea Sensor Final Report CRADA No. TSB-987-94. Office of Scientific and Technical Information (OSTI), 2018. http://dx.doi.org/10.2172/1431006.

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