Search Results - "Santra, Ashok"

Organically modified layered magnesium silicates to improve rheology of reservoir drilling fluids by Patel, Hasmukh A., Santra, Ashok

“…Petroleum well drilling fluids are one of the most significant constituents in the subterranean drilling processes to meet an increasing global demand for oil…”
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Portland cement solutions for ultra-high temperature wellbore applications by Pernites, Roderick B., Santra, Ashok K.

“…Designing highly stable and low permeability high-strength oil well cement above 500 °F (>260 °C) is extremely difficult because the Portland cement undergoes…”
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Various admixtures to mitigate the long-term strength retrogression of Portland cement cured under high pressure and high temperature conditions by Jiankun Qin, Xueyu Pang, Ashok Santra, Guodong Cheng, Hailong Li

“…In order to investigate the problem of long-term strength retrogression in oil well cement systems exposed to high pressure and high temperature (HPHT) curing…”
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Screening of forest tree leaves from North Eastern Himalayan region as feed additives for modulating in vitro rumen fermentation and methanogenesis from total mixed ration by Choudhary, Shilpa, Santra, Ashok, Muwel, Nirmala, Sarkar, Srobana, Mandal, Ajoy, Das, Subrata Kumar

“…Sustainable feeding practices using agroforestry plants with high nutritional value can replace costlier feed ingredients, reduce food feed competition and…”
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Editorial: Advances in wellbore servicing fluids and materials by Liu, Huajie, Pang, Xueyu, Santra, Ashok, Du, Jiapei

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Mechanism, Selectivity Promotion, and New Ultraselective Pathways in Ag-Catalyzed Heterogeneous Epoxidation by Williams, Federico J, Bird, Daniel P. C, Palermo, Alejandra, Santra, Ashok K, Lambert, Richard M

“…The selective oxidation of styrene on clean and modified Ag(100) surfaces has been studied by synchrotron fast XPS and temperature-programmed reaction…”
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On the Orientation of Quinoline on Pd{111}:  Implications for Heterogeneous Enantioselective Hydrogenation by Bonello, Jonathan M, Lindsay, Robert, Santra, Ashok K, Lambert, Richard M

“…The adsorption geometry of quinoid species at platinum and palladium surfaces is relevant to an understanding of enantioselective catalytic hydrogenation…”
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Ultraselective Epoxidation of Butadiene on Cu{111} and the Effects of Cs Promotion by Cowell, James J, Santra, Ashok K, Lambert, Richard M

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A novel star polymer for regulating fluid loss in oil-based mud under high temperature conditions by Jian, Guoqing, Santra, Ashok, Mbuncha, Christelle, Ross, Georgesha

“…Mechanisms of NSP stabilized Oil based Mud for fluid loss control. [Display omitted] •A star polymer was synthesized using RAFT polymerization as a superior…”
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Molecular Conformation of Styrene on Ag(100):  Relevance to an Understanding of the Catalytic Epoxidation of Terminal Alkenes by Williams, Federico J, Bird, Daniel P. C, Sykes, E. Charles H, Santra, Ashok K, Lambert, Richard M

“…Fast XPS and NEXAFS have been used to investigate the adsorption, desorption, and molecular conformation of styrene adsorbed on Ag(100) in order to determine…”
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Impervious synthetic layered silicates coating to restrict the swelling of clay‐rich shales by Patel, Hasmukh A., Santra, Ashok

“…An incremental demand towards the use of water‐based fluids for drilling oil and gas wells has generated numerous challenges in the field of shale inhibition…”
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Ultra-selective epoxidation of styrene on pure Cu{111} and the effects of Cs promotion by SANTRA, A. K, COWELL, J. J, LAMBERT, R. M

“…Styrene undergoes efficient epoxidation to styrene epoxide on the Cu{111} surface. At the optimum condition (Θo = 0.03 ML) ∼20% of the styrene is converted to…”
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Grafted graphene oxide nanoparticles as a yield point enhancer in water-based drilling fluids by Rong, Lihan, Santra, Ashok, Ross, Georgesha, Advincula, Rigoberto C.

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GROWTH OF Au ON TiO2(110) ON A CLUSTER-BY-CLUSTER BASIS by Santra, A K, Kolmakov, A, Yang, F, Goodman, D W

“…In-situ STM has been used to follow the growth mode of Au clusters on TiO2(110) single crystals at RT on a cluster-by-cluster basis. Using carefully annealed…”
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Anticipating gelation and vitrification with medium amplitude parallel superposition (MAPS) rheology and artificial neural networks by Lennon, Kyle R., Rathinaraj, Joshua David John, Gonzalez Cadena, Miguel A., Santra, Ashok, McKinley, Gareth H., Swan, James W.

“…Anticipating qualitative changes in the rheological response of complex fluids (e.g., a gelation or vitrification transition) is an important capability for…”
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The Chemistry of Sulfoxy Species on Clean, Oxygenated, and Caesiated Ag{100}:  A Study of Surface Reactivity by Fast XPS and TPR by Santra, Ashok K, Bird, Daniel P. C, Sykes, E. Charles H, Williams, Federico J, Goldoni, Andrea, Baraldi, Alessandro, Lambert, Richard M

“…High-resolution XPS, including time- and temperature-dependent measurements, and temperature-programmed reactions, including 18O isotope mixing studies, have…”
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In vitro digestibility and fermentation kinetics of some north eastern Himalayan tree leaves using cattle rumen fluid as inoculum by CHOUDHARY, SHILPA, SANTRA, ASHOK, SARKAR, SROBANA, DAS, S K

“…A study was undertaken to evaluate few north eastern Himalayan forest tree leaves [Blemkar (Buddleja asiatica), Phrengpa (Quercus walliasehiana), Maar…”
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Investigating temperature effect on degradation of well cement in HPHT carbonic acid environment by Omosebi, Omotayo, Maheshwari, Himanshu, Ahmed, Ramadan, Shah, Subhash, Osisanya, Samuel, Santra, Ashok, Saasen, Arild

“…Exposure of well cement to carbonated brine results in severe degradation. Under high-pressure high-temperature (HPHT) condition, the rate of attack increases…”
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Fundamental Aspects of Enantioselective Heterogeneous Catalysis:  the Surface Chemistry of Methyl Pyruvate on Pt{111} by Bonello, Jonathan M., Williams, Federico J., Santra, Ashok K., Lambert, Richard M.

“…STM, NEXAFS, XPS, and TPR have been used to characterize the adsorption and reactivity of methyl pyruvate on Pt{111}. In the absence of coadsorbed hydrogen,…”
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Growth of Au on TiO 2 (110) on a Cluster-by-Cluster Basis by Santra, Ashok K., Kolmakov, Andrei, Yang, Fan, Goodman, D. Wayne

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