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Study of Complex Nitrogen and Oxygen-bearing Molecules toward the High-mass Protostar IRAS 18089–1732

Research in Astronomy and Astrophysics 2024年第6期24卷 81-93页

作者： Arijit Manna Sabyasachi pal tapas Baug Sougata Mondal Department of Physics Midnapore City CollegePaschim MedinipurWest Bengal721129India S.N.Bose National Centre for Basic Sciences Block-JDSector-IIISalt Lake CityKolkata700106 India

The observation of oxygen(O)-and nitrogen(N)-bearing molecules gives an idea about the complex prebiotic chemistry in the interstellar *** millimeter and submillimeter wavelength observations have shown the presence of complex O-and N-bearing molecules in the star formation ***,the investigation of those molecules is crucial to understanding the chemical complexity in the star-forming *** this article,we present the identification of the rotational emission lines of N-bearing molecules ethyl cyanide(C_(2)H_(5)CN)and cyanoacetylene(HC_(3)N),and O-bearing molecule methyl formate(CH_(3)OCHO)toward high-mass protostar IRAS18089–1732 using the Atacama Compact *** also detected the emission lines of both the N-and O-bearing molecule formamide(NH_(2)CHO)in the envelope of IRAS 18089–*** have detected the v=0 and 1 state rotational emission lines of CH_(3)*** also detected the two vibrationally excited states of HC_(3)N(v7=1 and v7=2).The estimated fractional abundances of C_(2)H_(5)CN,HC_(3)N(v7=1),HC_(3)N(v7=2),and NH_(2)CHO toward IRAS 18089–1732 are(1.40±0.5)×10^(-10),(7.5±0.7)×10^(-11),(3.1±0.4)×10^(-11),and(6.25±0.82)×10^(-11)***,the estimated fractional abundances of CH_(3)OCHO(v=0)and CH_(3)OCHO(v=1)are(1.90±0.9)×10^(-9)and(8.90±0.8)×10^(-10),*** also created the integrated emission maps of the detected molecules,and the observed molecules may have originated from the extended envelope of the *** show that C_(2)H_(5)CNand HC_(3)N are most probably formed via the subsequential hydrogenation of the CH_(2)CHCNand the reaction between C_(2)H_(2)and CN on the grain surface of IRAS 18089–*** found that NH_(2)CHO is probably produced due to the reaction between NH_(2)and H_(2)CO in the gas ***,CH_(3)OCHO is possibly created via the reaction between radical CH_(3)O and radical HCO on the grain surface of IRAS 18089–1732.

关键词： ISM:individual objects(IRA 18089-1732)(except) ISM:abundances ISM:kinematics and dynamics stars:formation astrochemistry

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Polymethylmethacrylate Coated Alginate Matrix Microcapsules for Controlled Release of Diclofenac Sodium

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Pharmacology & Pharmacy 2011年第2期2卷 56-66页

作者： tapas pal Shubhajit Paul Biswanath Sa 不详

Polymethylmethacrylate (PMMA) coated microcapsules of diclofenac sodium (DFS) were prepared by a modified wa-ter-in-oil-in-water (W1/O/W2) emulsion solvent evaporation method using sodium alginate (SAL) as a matrix material in the internal aqueous phase (W1).Their performance with respect to controlled release of the drug in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) were evaluated, and compared with non-matrix microcapsules prepared by the conventional W1/O/W2 emulsion solvent evaporation method. Scanning electron micrographs (SEM) revealed that all the microcapsules were discrete and spherical in shape;however, the surface porosity of the matrix microcap-sules appeared to be less than that of the non-matrix microcapsules. In case of non-matrix microcapsules, an increase in the volume of water in W1 phase resulted in decrease in the drug entrapment efficiency (DEE) along with increase in release of the drug in both SGF and SIF. While in case of matrix microcapsules increase in the amount of SAL in W1 phase and concentration of the coating polymer in organic phase led to increase in DEE of the matrix microcapsules and considerable decrease in the drug release in both SGF and SIF. No interaction between the drug and any of the polymers used to prepare microcapsules was evident from Fourier transform infra-red (FTIR) analysis. The matrix microcapsules prepared using higher concentration of SAL and PMMA released the drug following zero order or Case-II transport model. The matrix microcapsules appeared to be suitable for releasing lesser amounts of DFS in SGF and providing extended release in SIF.

关键词： Polymethylmethacrylate Sodium Alginate Matrix Microcapsules Diclofenac Sodium Drug Release

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Effect of pyroxenite and olivine minerals as source of MgO in hematite pellet on improvement of metallurgical properties

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Journal of Central South University 2015年第9期22卷 3302-3310页

作者： Jagannath pal Satadal Ghorai Bikash Nandi tapas Chakraborty Goutam Das T.Venugopalan CSIR-National Metallurgical Laboratory Tata Steel

Pelletization of hematite ore requires high fineness and very high induration temperature（~1325 ℃） owing to its poor diffusion bonding unlike magnetite ore. Further, high-alumina hematite pellets show very high reduction degradation index（RDI） during low temperature（500-650 ℃） reduction due to their volume expansion and lattice distortion. Noamundi（India） hematite ore contains very high Al2O3（2.3%） with adverse ratio of alumina to silica（~2） for which, it shows very high RDI. In this work, the acid pellets prepared from Noamundi ore fines of optimum Blaine fineness show good cold crushing strength（CCS）. However, it shows very high RDI（77%）. In order to reduce RDI, Mg O in form of two different gangue-containing fluxes, such as pyroxenite and olivine in varying quantities has been added. The optimum requirement and performance of these fluxes has been examined and compared. Both pyroxenite and olivine fluxed pellets show significant lowering of RDI（26% and 23%, respectively） and improvement of other properties, viz CCS, swelling indices etc with good reducibility（70%-77%）. Finally, a good quality acidic hematite pellet was developed from high-alumina ore without using any lime which is very important charge material in combination of basic sinter in blast furnace.

关键词： hematite pellet high-alumina ore reduction degradation index(RDI) pyroxenite flux olivine flux effect of MgO

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Pre-treatment of rocks prior to comminution--A critical review of present practices

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International Journal of Mining Science and Technology 2017年第2期27卷 339-348页

作者： Somani Aditya Nandi tapas K. pal Samir K. Majumder Arun K. Department of Mining Engineering Indian Institute of TechnologyKharagpur 721302India Cryogenic Engineering Centre Indian Institute of TechnologyKharagpur 721302India

It has been an established fact that comminution processes, crushing and grinding, are most energy intensive processes which account for more than half of the total energy consumed in mineral *** alternative pre-treatment methods have been tried by experts around the globe. Although these methods yielded positive results in terms of reduction in energy consumption in crushing and particularly, in grinding operations at laboratory scale, their industrial application still remains an unresolved issue and challenge. Present review paper describes each one of these methods along with outcome of earlier studies and issues that need to be addressed through further rigorous experimental *** also suggests the direction in which future studies can be carried out to meet the primary objective of making comminution processes more energy efficient than today they are.

关键词： Comminution Rock breakage Microwave Thermal shock

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Determination of upper reference value of urinary calcium-creatinine ratio for the paediatric population in Burdwan district

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Advances in Biological Chemistry 2013年第5期3卷 455-459页

作者： Mrinal pal Subinay Datta Amit Kumar Pradhan tapas Ghosh Amrita Ganguly Shubhadeep Basu Joydeep Ghosh Rajarshi Rahut Department of Anatomy Burdwan Medical College Burdwan India Department of Biochemistry Burdwan Medical College Burdwan India

To estimate the rate of excretion of urinary calcium, a 24-hour sample of urine is required and this is not always easy to collect accurately in infant and children. So, random urine calcium to creatinine ratio (Ca/Cr ratio) has been developed. But as the ratio varies worldwide, reference values of the parameter in paediatric population are not developed. To determine reference value, the present study was conducted in healthy paediatric population in Burdwan district, West Bengal. This study was performed on 693 healthy paediatric subjects, aged between 3 months to 18 years and divided into five groups. Early morning non-fasting urine samples from all study groups were analyzed for Ca/Cr ratio. A negative correlation was observed between age and urinary Ca/Cr ratio, but there was no significant difference of urinary Ca/Cr ratio between two sexes. Considering 97.5th percentile of the underlying distribution of values as the upper limit of reference range, upper reference values of urinary Ca/Cr ratio for age groups

关键词： Urinary Calcium-Creatinine Ratio Hypercalcuria Reference Range

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