Rohit Kumar Rai - Academia.edu (original) (raw)
Papers by Rohit Kumar Rai
The Journal of the Association of Physicians of India, 2016
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
International journal of scientific research, 2016
Endoscopic retrograde cholangio-pancreaticography (ERCP) followed by laparoscopic cholecystectomy... more Endoscopic retrograde cholangio-pancreaticography (ERCP) followed by laparoscopic cholecystectomy comprises the current treatment modality in patients with common bile duct stones. The optimum time interval between Endoscopic retrograde cholangiopancreaticography and laparoscopic cholecystectomy is questionable. A total of 150 patients admitted with uncomplicated cholelithiasis with choledocholithiasis, were included in this study. They were divided randomly by chit pot method in two groups, Group A (75 patients) who underwent laparoscopic cholecystectomy within 72 hours of ERCP, and Group B(75 patients) ,who underwent laparoscopic cholecystectomy atleast more than 72 hours after ERCP. In the present study, mean operative time in group A was significantly higher in group B as compared to group A. Post operative hospital stay was found significantly higher in group B. The longer the time interval between ERCP and laparoscopic cholecystectomy, the higher are the chances of encounteri...
Catalysis Science & Technology, 2020
Bimetallic Ni–Fe catalysts (Ni/Fe, 1 : 1, 1 : 3, and 3 : 1) are synthesized and explored for thei... more Bimetallic Ni–Fe catalysts (Ni/Fe, 1 : 1, 1 : 3, and 3 : 1) are synthesized and explored for their catalytic activity in semihydrogenation of internal alkynes using H2 gas in water–ethanol solution.
Catalysis Science & Technology, 2020
Highly efficient and very stable iron and/or cobalt-based catalysts for the ammonia synthesis rea... more Highly efficient and very stable iron and/or cobalt-based catalysts for the ammonia synthesis reaction were synthesized by one-step pyrolysis of metal phthalocyanine precursors.
International Journal Of Community Medicine And Public Health, 2018
Background: Electrical burn injuries (EBI) comprise a small proportion of the total burn admissio... more Background: Electrical burn injuries (EBI) comprise a small proportion of the total burn admissions but they inflict significant morbidity. The objective of this study was to analyse recent epidemiologic data and identify prevention measures.Methods: A retrospective study was conducted by reviewing the medical records of all burn admissions from April 2016 to March 2018 and data was analysed for demographic characteristics and outcomes and patterns of electric burn injury.Results: A total of 3136 admissions were made. Male to female ratio was 1.5:1.0. Rural: urban ratio was 2:1. Mode of injury was accidental (79%), suicidal (12%) and homicidal (9%). Flame burn (64.47%) topped the list of etiologic factors. Electric burn represented 24.49% which was quite significant when compared to other parts of the world. 1042 patients expired (33.22%). Out of the total electric burn admissions, 768 (24.49%) patients were of electric injury. 207 (27.01%) patients sustained low voltage (<1000 ...
Chemistry, an Asian journal, Jan 6, 2018
Catalytic dehydrogenation of hydrazine in THF and ethanol was achieved over ruthenium-arene compl... more Catalytic dehydrogenation of hydrazine in THF and ethanol was achieved over ruthenium-arene complexes containing Nimine-substituted iminopyridine ligands [(h6-benzene)Ru(κ2-L)Cl]+ (L = N-hydroxy-iminopyridine, N-methoxy-iminopyridine and N-iso-propyl-iminopyridine). Our findings demonstrated that the catalytic activity for the release of H2 and N2 gases, as confirmed by GC-TCD, from hydrazine depends on the temperature (30 ºC - 80 ºC), base (KOtBu and KOH), and solvents used (THF, ethanol and water). Moreover, the studied complex displayed excellent recyclability for the dehydrogenation of hydrazine (in THF) for six consecutive catalytic runs. 1H NMR and mass spectrometric studies revealed the formation of hydrazine (and phenylhydrazine) coordinated Ru(II)-arene intermediate [(h6-C6H6)Ru(κ2-L)(RNHNH2)]+ (R = H or Ph), where the coordination of hydrazine to Ru center and subsequent activation of hydrazine (Ea = 57.9 kJmol-1) was expected to be the key step involved in achieving dehyd...
Physica B+C, 1988
The 'E,,(e&ai,) ground state of chromocene is treated as a system consisting of two holes, one in... more The 'E,,(e&ai,) ground state of chromocene is treated as a system consisting of two holes, one in the ezl and the other in the a,, orbital. By a suitable choice of the basis vectors the vibronic eigenvalue equations of this case are transformed into isomorphic forms to the corresponding equation for the one electron case. The method of canonical transformation and variational approach developed in part I therefore is applied to chromocene also. The variational wavefunctions and energies are used to explain the EPR and Raman spectroscopy results on the complex.
European Journal of Inorganic Chemistry, 2017
Efficient and selective catalytic reduction of aqueous nitrate to ammonia was achieved over Ni na... more Efficient and selective catalytic reduction of aqueous nitrate to ammonia was achieved over Ni nanoparticles immobilized on Fe 3 O 4 @n-SiO 2 @H-SiO 2-NH 2 (magnetic hierarchical mesoporous amine-functionalized: M-HMAF) silica using hydrazine hydrate as a reducing agent. High hierarchical mesoporous structure (surface area of 416 m 2 •g-1 and pore size of 3.7 nm) and Fe 3 O 4 core (ca. 7 nm) of the M-HMAF silica support resulted in, a high dispersion of Ni nanoparticles over the support and an easy recovery of the catalyst, respectively. Interestingly, Ni/M-HMAF silica catalyst exhibited excellent catalytic turnover (275 mmol•g metal-1 •h-1), as compare to most of the existing catalysts for the conversion of nitrate ions at room temperature. Mechanistic study using UV-vis spectroscopy revealed that the catalytic conversion of nitrate ions to ammonia proceeded through in-situ generated nitrite ions. Subsequently, the ammonia produced from nitrate ions was isolated and analyzed by 1 H and 15 N NMR, whereas N 2 gas released as a by-product of hydrazine was characterized by GC-MS.
ChemCatChem, 2017
We describe a tandem process to in situ generate active ruthenium nanoparticles (ca 7 nm) immobil... more We describe a tandem process to in situ generate active ruthenium nanoparticles (ca 7 nm) immobilized on carbon, from an organometallic precursor and formic acid, to afford hydrogenation of a wide range of arenes and heteroarenes in yields up to 72%, with high conversions and selectivities for the desired products. Hydrogenation of several substrates analogous to lignin-derived fragments, to corresponding alicyclic products was also achieved. Our experimental investigations evidenced that the observed enhanced activity for arene hydrogenation was driven by the unique structural advantage with the organometallic precursor to activate formic acid, where the presence of a nitrogen ligand is crucial to achieve higher catalytic activity. TEM analysis revealed the formation of Ru(0) nanoparticles and Hg(0) poisoning experiments supporting the heterogeneous nature of the active catalyst.
The Journal of the Association of Physicians of India, 2016
SPE Advanced Technology Series, 1996
There is a general concern in the oil industry regarding the flow of crudes at temperatures below... more There is a general concern in the oil industry regarding the flow of crudes at temperatures below the pour point. However, this concern is not valid as long as adequate pressure is available to maintain the continuous flow. Practically, pumping of waxy crudes below the pour point is quite common for the transportation of such crudes. Multiphase waxy crude is associated with dissolved and free gas; water can be present either as free water or in emulsion form; and gas-liquid flow pattern such as slug flow may occur with turbulent mixing. All these tend to decrease the congealing of the waxy crudes. An analysis of a case history has been carried out on the possibility of congealing of high waxy multiphase flow lines considering above governing parameters. The analysis includes normal operating condition as well as shut down and start up of the pipeline. The analysis confirmed that the congealing of crude in pipeline should not be concluded simply based on the pour point of the dead cr...
The Journal of the Association of Physicians of India, 2016
Chemistry, an Asian journal, Jan 23, 2016
Water-soluble arene-ruthenium complexes coordinated with readily available aniline based ligands ... more Water-soluble arene-ruthenium complexes coordinated with readily available aniline based ligands were successfully employed to achieve high catalytic activity towards C-H bond activation and arylation of 2-phenylpyridine with arylhalides in water. A variety of (hetero)arylhalides were also used for the ortho-C-H bond arylation of 2-phenylpyridine to afford the corresponding ortho- monoarylated products as major products in moderate to good yields. Our investigations, including time-scaled NMR and mass spectral studies, evidenced that the coordinating aniline based ligands, having varying electronic and steric behavior, exert significant influence on the catalytic activity of the resulting arene-ruthenium-aniline based complexes. Moreover, mass spectral identification of the cycloruthenated species, {(h6-arene)Ru(2-C,N-phenylpyridine)}+, and several ligand coordinated cycloruthenated species, such as [(h6-arene)Ru(4-methylaniline)(2-C,N-phenylpyridine)]+, during the reaction of 2-phe...
Bioresource technology, 2016
Penicillium sp. (Dal 5) isolated from rhizosphere of conifers from Dalhousie (Himachal Pradesh, I... more Penicillium sp. (Dal 5) isolated from rhizosphere of conifers from Dalhousie (Himachal Pradesh, India) was found to be an efficient cellulolytic strain. The culture under shake flask on CWR (cellulose, wheat bran and rice straw) medium produced appreciably higher levels of endoglucanase (35.69U/ml), β-glucosidase (4.20U/ml), cellobiohydrolase (2.86U/ml), FPase (1.2U/ml) and xylanase (115U/ml) compared to other Penicillium strains reported in literature. The mass spectroscopy analysis of Penicillium sp. Dal 5 secretome identified 108 proteins constituting an array of CAZymes including glycosyl hydrolases (GH) belonging to 24 different families, polysaccharide lyases (PL), carbohydrate esterases (CE), lytic polysaccharide mono-oxygenases (LPMO) in addition to swollenin and a variety of carbohydrate binding modules (CBM) indicating an elaborate genetic potential of this strain for hydrolysis of lignocellulosics. Further, the culture extract was evaluated for hydrolysis of alkali treate...
Catalysis Science & Technology, 2016
This minireview highlights the recent progress made in the last decade towards the development of... more This minireview highlights the recent progress made in the last decade towards the development of activated bimetallic alloy nanoparticle catalysts for C–C coupling reactions, including asymmetric C–C bond coupling reactions.
A process using a three-piece mold for making a three-dimensionally shaped glass article having a... more A process using a three-piece mold for making a three-dimensionally shaped glass article having a flat area and a curved/bend area is disclosed. The process includes placing a glass sheet on a mold having a shaping surface with a desired surface profile for the shaped glass article including a flat area and a bend area, moving a flat area plunger toward the glass sheet to compress the glass sheet, heating a portion of the glass sheet corresponding to an area above the bend area of the mold to a temperature above a forming temperature, and moving a bend area plunger toward the heated glass sheet to compress the heated glass sheet. A temperature of the glass sheet in the area above the bend area of the mold is higher than a temperature of the glass sheet in the area above the flat area of the mold when compressing the heated glass sheet with the bend area plunger.
Journal of the Andaman Science Association, 1990
The Journal of the Association of Physicians of India, 2016
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
International journal of scientific research, 2016
Endoscopic retrograde cholangio-pancreaticography (ERCP) followed by laparoscopic cholecystectomy... more Endoscopic retrograde cholangio-pancreaticography (ERCP) followed by laparoscopic cholecystectomy comprises the current treatment modality in patients with common bile duct stones. The optimum time interval between Endoscopic retrograde cholangiopancreaticography and laparoscopic cholecystectomy is questionable. A total of 150 patients admitted with uncomplicated cholelithiasis with choledocholithiasis, were included in this study. They were divided randomly by chit pot method in two groups, Group A (75 patients) who underwent laparoscopic cholecystectomy within 72 hours of ERCP, and Group B(75 patients) ,who underwent laparoscopic cholecystectomy atleast more than 72 hours after ERCP. In the present study, mean operative time in group A was significantly higher in group B as compared to group A. Post operative hospital stay was found significantly higher in group B. The longer the time interval between ERCP and laparoscopic cholecystectomy, the higher are the chances of encounteri...
Catalysis Science & Technology, 2020
Bimetallic Ni–Fe catalysts (Ni/Fe, 1 : 1, 1 : 3, and 3 : 1) are synthesized and explored for thei... more Bimetallic Ni–Fe catalysts (Ni/Fe, 1 : 1, 1 : 3, and 3 : 1) are synthesized and explored for their catalytic activity in semihydrogenation of internal alkynes using H2 gas in water–ethanol solution.
Catalysis Science & Technology, 2020
Highly efficient and very stable iron and/or cobalt-based catalysts for the ammonia synthesis rea... more Highly efficient and very stable iron and/or cobalt-based catalysts for the ammonia synthesis reaction were synthesized by one-step pyrolysis of metal phthalocyanine precursors.
International Journal Of Community Medicine And Public Health, 2018
Background: Electrical burn injuries (EBI) comprise a small proportion of the total burn admissio... more Background: Electrical burn injuries (EBI) comprise a small proportion of the total burn admissions but they inflict significant morbidity. The objective of this study was to analyse recent epidemiologic data and identify prevention measures.Methods: A retrospective study was conducted by reviewing the medical records of all burn admissions from April 2016 to March 2018 and data was analysed for demographic characteristics and outcomes and patterns of electric burn injury.Results: A total of 3136 admissions were made. Male to female ratio was 1.5:1.0. Rural: urban ratio was 2:1. Mode of injury was accidental (79%), suicidal (12%) and homicidal (9%). Flame burn (64.47%) topped the list of etiologic factors. Electric burn represented 24.49% which was quite significant when compared to other parts of the world. 1042 patients expired (33.22%). Out of the total electric burn admissions, 768 (24.49%) patients were of electric injury. 207 (27.01%) patients sustained low voltage (<1000 ...
Chemistry, an Asian journal, Jan 6, 2018
Catalytic dehydrogenation of hydrazine in THF and ethanol was achieved over ruthenium-arene compl... more Catalytic dehydrogenation of hydrazine in THF and ethanol was achieved over ruthenium-arene complexes containing Nimine-substituted iminopyridine ligands [(h6-benzene)Ru(κ2-L)Cl]+ (L = N-hydroxy-iminopyridine, N-methoxy-iminopyridine and N-iso-propyl-iminopyridine). Our findings demonstrated that the catalytic activity for the release of H2 and N2 gases, as confirmed by GC-TCD, from hydrazine depends on the temperature (30 ºC - 80 ºC), base (KOtBu and KOH), and solvents used (THF, ethanol and water). Moreover, the studied complex displayed excellent recyclability for the dehydrogenation of hydrazine (in THF) for six consecutive catalytic runs. 1H NMR and mass spectrometric studies revealed the formation of hydrazine (and phenylhydrazine) coordinated Ru(II)-arene intermediate [(h6-C6H6)Ru(κ2-L)(RNHNH2)]+ (R = H or Ph), where the coordination of hydrazine to Ru center and subsequent activation of hydrazine (Ea = 57.9 kJmol-1) was expected to be the key step involved in achieving dehyd...
Physica B+C, 1988
The 'E,,(e&ai,) ground state of chromocene is treated as a system consisting of two holes, one in... more The 'E,,(e&ai,) ground state of chromocene is treated as a system consisting of two holes, one in the ezl and the other in the a,, orbital. By a suitable choice of the basis vectors the vibronic eigenvalue equations of this case are transformed into isomorphic forms to the corresponding equation for the one electron case. The method of canonical transformation and variational approach developed in part I therefore is applied to chromocene also. The variational wavefunctions and energies are used to explain the EPR and Raman spectroscopy results on the complex.
European Journal of Inorganic Chemistry, 2017
Efficient and selective catalytic reduction of aqueous nitrate to ammonia was achieved over Ni na... more Efficient and selective catalytic reduction of aqueous nitrate to ammonia was achieved over Ni nanoparticles immobilized on Fe 3 O 4 @n-SiO 2 @H-SiO 2-NH 2 (magnetic hierarchical mesoporous amine-functionalized: M-HMAF) silica using hydrazine hydrate as a reducing agent. High hierarchical mesoporous structure (surface area of 416 m 2 •g-1 and pore size of 3.7 nm) and Fe 3 O 4 core (ca. 7 nm) of the M-HMAF silica support resulted in, a high dispersion of Ni nanoparticles over the support and an easy recovery of the catalyst, respectively. Interestingly, Ni/M-HMAF silica catalyst exhibited excellent catalytic turnover (275 mmol•g metal-1 •h-1), as compare to most of the existing catalysts for the conversion of nitrate ions at room temperature. Mechanistic study using UV-vis spectroscopy revealed that the catalytic conversion of nitrate ions to ammonia proceeded through in-situ generated nitrite ions. Subsequently, the ammonia produced from nitrate ions was isolated and analyzed by 1 H and 15 N NMR, whereas N 2 gas released as a by-product of hydrazine was characterized by GC-MS.
ChemCatChem, 2017
We describe a tandem process to in situ generate active ruthenium nanoparticles (ca 7 nm) immobil... more We describe a tandem process to in situ generate active ruthenium nanoparticles (ca 7 nm) immobilized on carbon, from an organometallic precursor and formic acid, to afford hydrogenation of a wide range of arenes and heteroarenes in yields up to 72%, with high conversions and selectivities for the desired products. Hydrogenation of several substrates analogous to lignin-derived fragments, to corresponding alicyclic products was also achieved. Our experimental investigations evidenced that the observed enhanced activity for arene hydrogenation was driven by the unique structural advantage with the organometallic precursor to activate formic acid, where the presence of a nitrogen ligand is crucial to achieve higher catalytic activity. TEM analysis revealed the formation of Ru(0) nanoparticles and Hg(0) poisoning experiments supporting the heterogeneous nature of the active catalyst.
The Journal of the Association of Physicians of India, 2016
SPE Advanced Technology Series, 1996
There is a general concern in the oil industry regarding the flow of crudes at temperatures below... more There is a general concern in the oil industry regarding the flow of crudes at temperatures below the pour point. However, this concern is not valid as long as adequate pressure is available to maintain the continuous flow. Practically, pumping of waxy crudes below the pour point is quite common for the transportation of such crudes. Multiphase waxy crude is associated with dissolved and free gas; water can be present either as free water or in emulsion form; and gas-liquid flow pattern such as slug flow may occur with turbulent mixing. All these tend to decrease the congealing of the waxy crudes. An analysis of a case history has been carried out on the possibility of congealing of high waxy multiphase flow lines considering above governing parameters. The analysis includes normal operating condition as well as shut down and start up of the pipeline. The analysis confirmed that the congealing of crude in pipeline should not be concluded simply based on the pour point of the dead cr...
The Journal of the Association of Physicians of India, 2016
Chemistry, an Asian journal, Jan 23, 2016
Water-soluble arene-ruthenium complexes coordinated with readily available aniline based ligands ... more Water-soluble arene-ruthenium complexes coordinated with readily available aniline based ligands were successfully employed to achieve high catalytic activity towards C-H bond activation and arylation of 2-phenylpyridine with arylhalides in water. A variety of (hetero)arylhalides were also used for the ortho-C-H bond arylation of 2-phenylpyridine to afford the corresponding ortho- monoarylated products as major products in moderate to good yields. Our investigations, including time-scaled NMR and mass spectral studies, evidenced that the coordinating aniline based ligands, having varying electronic and steric behavior, exert significant influence on the catalytic activity of the resulting arene-ruthenium-aniline based complexes. Moreover, mass spectral identification of the cycloruthenated species, {(h6-arene)Ru(2-C,N-phenylpyridine)}+, and several ligand coordinated cycloruthenated species, such as [(h6-arene)Ru(4-methylaniline)(2-C,N-phenylpyridine)]+, during the reaction of 2-phe...
Bioresource technology, 2016
Penicillium sp. (Dal 5) isolated from rhizosphere of conifers from Dalhousie (Himachal Pradesh, I... more Penicillium sp. (Dal 5) isolated from rhizosphere of conifers from Dalhousie (Himachal Pradesh, India) was found to be an efficient cellulolytic strain. The culture under shake flask on CWR (cellulose, wheat bran and rice straw) medium produced appreciably higher levels of endoglucanase (35.69U/ml), β-glucosidase (4.20U/ml), cellobiohydrolase (2.86U/ml), FPase (1.2U/ml) and xylanase (115U/ml) compared to other Penicillium strains reported in literature. The mass spectroscopy analysis of Penicillium sp. Dal 5 secretome identified 108 proteins constituting an array of CAZymes including glycosyl hydrolases (GH) belonging to 24 different families, polysaccharide lyases (PL), carbohydrate esterases (CE), lytic polysaccharide mono-oxygenases (LPMO) in addition to swollenin and a variety of carbohydrate binding modules (CBM) indicating an elaborate genetic potential of this strain for hydrolysis of lignocellulosics. Further, the culture extract was evaluated for hydrolysis of alkali treate...
Catalysis Science & Technology, 2016
This minireview highlights the recent progress made in the last decade towards the development of... more This minireview highlights the recent progress made in the last decade towards the development of activated bimetallic alloy nanoparticle catalysts for C–C coupling reactions, including asymmetric C–C bond coupling reactions.
A process using a three-piece mold for making a three-dimensionally shaped glass article having a... more A process using a three-piece mold for making a three-dimensionally shaped glass article having a flat area and a curved/bend area is disclosed. The process includes placing a glass sheet on a mold having a shaping surface with a desired surface profile for the shaped glass article including a flat area and a bend area, moving a flat area plunger toward the glass sheet to compress the glass sheet, heating a portion of the glass sheet corresponding to an area above the bend area of the mold to a temperature above a forming temperature, and moving a bend area plunger toward the heated glass sheet to compress the heated glass sheet. A temperature of the glass sheet in the area above the bend area of the mold is higher than a temperature of the glass sheet in the area above the flat area of the mold when compressing the heated glass sheet with the bend area plunger.
Journal of the Andaman Science Association, 1990