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Green and Sustainable Chemistry 2015年第3期5卷 128-135页

作者： pranab jyoti das Jesmin Begum Department of Chemistry Gauhati University Guwahati India

A microwave mediated solvent free one pot synthesis of formazans is developed using the solid acid, KHSO4. The products were obtained in a short reaction time in high yield. This study was undertaken to find an alternative and green method for the synthesis of formazans in the absence of corrosive mineral acids, buffered solutions and volatile organic compounds (VOCs).

关键词： Formazan One Pot Synthesis Solvent Free Four Component Reaction Microwave KHSO4

Solvent Free One-Pot Synthesis of 1,2,4,5-Tetrasubstituted Imidazoles Catalyzed by Secondary Amine Based Ionic Liquid and Defective Keggin Heteropoly Acid

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Green and Sustainable Chemistry 2013年第4期3卷 6-13页

作者： pranab jyoti das Jupitara das Munni Ghosh Sabera Sultana Department of Chemistry Gauhati University Guwahati India Indian Institute of Technology Guwahati India

Secondary amine based ionic liquid and defective Keggin type heteropoly acid (HPA) are separately used for efficient one-pot four-component synthesis of 1,2,4,5-tetrasubstituted imidazoles assisted by microwave (MW). Eco-friendly solvent free procedure, short reaction time, high yield of products and reusability of catalysts are important features of the synthesis. A comparative study on the efficiency of the two catalysts is reported. This work further demonstrates the alternate use of urea, instead of often used ammonium acetate, as source of nitrogen.

关键词： Ionic Liquids Keggin Heteropolyacid Microwave Tetrasubstituted Imidazole Solvent Free Synthesis Multicomponent Reaction

Robustness Study and Superior Method Development and Validation for Analytical Assay Method of Atropine Sulfate in Pharmaceutical Ophthalmic Solution

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American Journal of Analytical Chemistry 2024年第5期15卷 151-164页

作者： Md. Nazmus Sakib Chowdhury Sreekanta Nath Dalal Md. Ariful Islam Md. Anwar Hossain pranab Kumar das Shakawat Hossain Parajit das Department of Pharmacy Bangabandhu Sheikh Mujibur Rahman Science and Technology University Gopalganj Bangladesh Department of Applied Chemistry and Chemical Engineering University of Dhaka Dhaka Bangladesh Department of Applied Chemistry and Chemical Engineering University of Chittagong Chattogram Bangladesh Department of Applied Chemistry and Chemical Engineering Islamic University Kushtia Bangladesh Department of Applied Chemistry and Chemical Engineering University of Rajshahi Rajshahi Bangladesh Department of Pharmacy International Islamic University Chittagong Chittagong Bangladesh Department of Applied Chemistry and Chemical Engineering Bangabandhu Sheikh Mujibur Rahman Science and Technology University Gopalganj Bangladesh

Background: The robustness is a measurement of an analytical chemical method and its ability to contain unaffected by little with deliberate variation of analytical chemical method parameters. The analytical chemical method variation parameters are based on pH variability of buffer solution of mobile phase, organic ratio composition changes, stationary phase (column) manufacture, brand name and lot number variation;flow rate variation and temperature variation of chromatographic system. The analytical chemical method for assay of Atropine Sulfate conducted for robustness evaluation. The typical variation considered for mobile phase organic ratio change, change of pH, change of temperature, change of flow rate, change of column etc. Purpose: The aim of this study is to develop a cost effective, short run time and robust analytical chemical method for the assay quantification of Atropine in Pharmaceutical Ophthalmic Solution. This will help to make analytical decisions quickly for research and development scientists as well as will help with quality control product release for patient consumption. This analytical method will help to meet the market demand through quick quality control test of Atropine Ophthalmic Solution and it is very easy for maintaining (GDP) good documentation practices within the shortest period of time. Method: HPLC method has been selected for developing superior method to Compendial method. Both the compendial HPLC method and developed HPLC method was run into the same HPLC system to prove the superiority of developed method. Sensitivity, precision, reproducibility, accuracy parameters were considered for superiority of method. Mobile phase ratio change, pH of buffer solution, change of stationary phase temperature, change of flow rate and change of column were taken into consideration for robustness study of the developed method. Results: The limit of quantitation (LOQ) of developed method was much low than the compendial method. The % RSD fo

关键词： Robustness Method Validation HPLC Compendial Method Method Development GDP LOQ

Environmental impact of aquaculture-sedimentation and nutrient loadings from shrimp culture of the southeast coastal region of the Bay of Bengal

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Journal of Environmental Sciences 2004年第3期16卷 466-470页

作者： Biplob das Yusuf Sharif Ahmed Khan pranab das Department of Earth and Atmospheric Sciences Institute of Marine SciencesInstitute of Marine Sciences 1-26 Earth Sciences Building University of Alberta Edmonton Alberta T6G 2E3CanadaUniversity of ChittagongChittagong 4331BangladeshUniversity of ChittagongChittagong 4331Bangladesh

Nutrient loadings were measured for surface seawater and bottom sediments of semi intensive and improved extensive shrimp culture pond, adjacent estuary, and fallow land in the south east coastal region of Bangladesh during August, 2000—January, 2001 to evaluate the impact of shrimp culture. The mean levels of nutrients found in the pond surface water were 108 780 mg/L for CaCO 3, 0 526 mg/L for NH + 4 N, 3 075 wt% for organic carbon, 7 00 mg/L for PO 4 P, 5 57 mg/L for NO 3 N, and 7 33 mg/L for chlorophyll a. The maximum mean value of H 2S(0 232 mg/L) was found in estuarine water. Nutrients loading were found to be decreased with distance from the shrimp farm discharge unit in estuarine water. The mean level of organic matter, total nitrogen, and organic carbon were found in higher concentrations in sediments of cultured pond compared to bottom soil of adjacent fallow land at the same elevation. Extractable Ca values were found in higher concentration(550 33 ppt) in adjacent fallow land, as the shrimps for molting in shrimp ponds use extractable Ca. The relation between seawater H 2S value and sediment pH ( r= -0 94); sediment organic carbon and sediment pH values ( r= -0 76), sediment total nitrogen and sediment pH ( r= - 0 74) were found to be highly negatively correlated. Whereas the relation between seawater H 2S value and sediment total nitrogen ( r= 0 92), water NH + 4 N and sediment pH ( r= 0 66) were found to be positively correlated. The results revealed that load of nutrients at eutrophic level in estuarine water, and decrease of soil pH; leading to acid sulphate soil formation indicates a negative impact of shrimp culture.

关键词： environment eutrophication impact nutrients shrimp culture

Petrological Characteristics and Genesis of the Central Indian Ocean Basin Basalts

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Acta Geologica Sinica(English Edition) 2012年第5期86卷 1154-1170页

作者： pranab das Sridhar D.IYER Sugata HAZRA National Institute of Oceanography(Council of Scientific and Industrial Research)Dona Paula Goa 403004India Department of Applied Geology Indian School of MinesDhanbad 826004India School of Oceanographic Studies Jadavpur UniversityKolkata 700032India

The Central Indian Ocean Basin （CIOB） basalts are plagioclase-rich, while olivine and pyroxene are very few. The analyses of 41 samples reveal high FeOT （～10-18 wt%） and TiO 2 （～1.4-2.7 wt%） indicating a ferrobasaltic composition. The basalts have high incompatible elements （Zr 63-228 ppm; Nb ～1-5 ppm; Ba ～15-78 ppm; La ～3-16 ppm）, a similar U/Pb （0.02-0.4） ratio as the normal midoceanic basalt （0.16±0.07） but the Ba/Nb （12.5-53） ratio is much larger than that of the normal midoceanic ridge basalt （～5.7） and Primitive Mantle （9.56）. Interestingly almost all of the basalts have a significant negative Eu anomaly （Eu/Eu＊=0.78-1.00） that may have been a result of the removal of feldspar and pyroxene during crystal fractionation. These compositional variations suggest that the basalts were derived through fractional crystallization together with low partial melting of a shallow seated magma.

关键词： basalts Genesis Central Indian Ocean Basin

A strategic way of high-performance energy storage device development with environmentally viable “Water-in-salt” electrolytes

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Journal of Energy Chemistry 2023年第3期78卷 350-373,I0010页

作者： Prakas Samanta Souvik Ghosh Aniruddha Kundu pranab Samanta Naresh Chandra Murmu Tapas Kuila Surface Engineering&Tribology Division Council of Scientific and Industrial Research Central Mechanical Engineering Research InstituteMahatma Gandhi AvenueDurgapur-713209West BengalIndia Academy of Scientific and Innovative Research(AcSIR) CSIR-Human Resource Development Centre(CSIR-HRDC)CampusPostal Staff College AreaSector 19Kamla Nehru NagarGhaziabad-201002Uttar PradeshIndia

Development of cost-effective and environmental friendly energy storage devices(ESDs) has attracted widespread attention in recent scenario of energy ***,the environmentally viable "water-in-salt"(WiS) electrolytes has received significant interest for the development of advanced high performance *** WiS electrolyte exhibits wide electrochemical stability window(ESW),highsafety,non-flammability and superior electrochemical performance compared to the conventional "salt-in-water" *** review aims to provide a comprehensive discussion on WiS electrolyte based on theoretical,electrochemical and physicochemical characteristics.A strategic way for the usage of WiS electrolyte in rechargeable metal-ion batteries and supercapacitors with potentially improved electrochemical performance has been reviewed *** review also discussed the unique advantages of WiS electrolytes as well as the future scope and challenges.

关键词： Water-in-salt electrolyte Solid electrolyte interphase High energy density Aqueous batteries Aqueous supercapacitors

Nutritional Outcome and Growth Monitoring in Under-Five Children of Severe Acute Malnutrition with and without Edema in Bangladesh: A Five-Year Retrospective Review of Facility-Based Inpatient Care

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Open Journal of Pediatrics 2022年第4期12卷 633-646页

作者： Zabeen Choudhury Mohammad Musa Meah Aparup Kanti das pranab Kumar Chowdhury Dhiman das Department of Pediatrics Chittagong Medical College Chattogram Bangladesh

Introduction: Severe acute malnutrition (SAM) is an important cause of death in children. Bangladesh has a huge burden of SAM in under-five children, but documentation of their protocolized management and outcome is not so frequent. Objective: Our aim was to identify the pattern of the nutritional outcome and growth monitoring of 0-59 months old children with severe acute malnutrition treated with identified medical complications where the presence or absence of edema is an important clinical factor. Methods: This was a facility-based retrospective observational study that was conducted in the Severe Acute Malnutrition block of Chittagong Medical College Hospital, Chittagong. Here, a total of 485 patients were admitted during the period from 2013 to 2017. Based on WHO & National guidelines, admission and discharge criteria were considered and determined. A structured and prescribed data format was prepared and data were collected from the hospital records. Daily clinical follow-ups and weight monitoring of the patients were also documented. Both descriptive and analytic analyses were executed. After Data collection, it was cleaned, edited, and stored in excel, epi-INFO, and analyzed by SPSS. P-value rd of the admitted patients stayed in the hospital for two weeks. The mean duration of hospital stay (in days) of the patients with edema (15.64 ± SD 7.133 days) was higher than that of the patients without edema (9.47 ± SD 5.881 days). 4.3% of patients did not gain weight during their hospital stay, and overall

关键词： Severe Acute Malnutrition (SAM) Nutritional Outcome Growth Monitoring

Microtexture and Distribution of Minerals in Hydrothermal Barite-Silica Chimney from the Franklin Seamount, SW Pacific: Constraints on Mode of Formation

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Acta Geologica Sinica(English Edition) 2014年第1期88卷 213-225页

作者： Durbar RAY Dalayya KOTA pranab das L.Surya Prakash V.D.KHEDEKAR Anil L.PAROPKARI Abhay V.MUDHOLKAR CSIR-National Institute of Oceanography Indian School of Mines

An extinct hydrothermal barite-silica chimney from the Franklin Seamount of the Woodlark Basin, in the southwestern Pacific Ocean, was investigated for mineral distribution and geochemical composition. Six layers on either side of the orifice of a chimney show significant disparity in color, mineral assemblage and major element composition. Electron microscope（SEM） images reveal that the peripheral wall of the chimney is composed of colloform silica, suggesting that incipient precipitation of silica-saturated hydrothermal fluid initiated the development of the chimney wall. Intermediate layers, between the exterior wall and the inner fluid-orifice, dominate with barite and sulfides. Low Sr-to-Ba ratios（SrO/BaO = 0.015–0.017） indicate restricted fluid-seawater mixing, which causes relatively high-temperature formation of the intermediate layers. Whereas the innermost layer bordering the chimney orifice is characterized by more silica and a higher Sr-to-Ba ratio（SrO/BaO = 0.023）, could have formed due to a paragenetic shift from a high-temperature active phase to a cooler waning stage of formation. A paragenetic shift is also probably responsible for the change in mineral formation mechanism that resulted in the textural variation of barite and colloform silica developed during different growth phases of this barite-silica chimney.

关键词： mineralogy oceanography geochemistry Franklin seamount barite-silica chimney

Improved photocatalytic degradation of organic dye using Ag3PO4/MoS2 nanocomposite

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Frontiers of Materials Science 2017年第4期11卷 366-374页

作者： Madhulika SHARMA pranab Kishore MOHAPATRA Dhirendra BAHADUR Department of Metallurgical Engineering and Materials Science Indian Institute of Technology Bombay Powai Mumbai 400076 India Department of Physics Indian Institute of Technology Bombay Powai Mumbai 400076 India

Highly efficient Ag3PO4/MoS2 nanocomposite photocatalyst was synthe- sized using a wet chemical route with a low weight percentage of highly exfoliated MoS2 （0.1 wt.%） and monodispersed Ag3PO4 nanoparticles （-5.4 nm）. The structural and optical properties of the nanocomposite were studied using various characterization techniques, such as XRD, TEM, Raman and absorption spectroscopy. The composite exhibits markedly enhanced photocatalytic activity with a low lamp power （60 W）. Using this composite, a high kinetic rate constant （k） value of 0.244 min^-1 was found. It was observed that -97.6% of dye degrade over the surface of nanocomposite catalyst within 15 min of illumination. The improved photocatalytic activity of Ag3PO4/MoS2 nanocomposite is attributed to the efficient interfacial charge separation, which was supported by the PL results. Large surface area of MoS2 nanosheets incorporated with well dispersed Ag3PO4 nanoparticles further increases charge separation, contributing to enhanced degradation efficiency. A possible mechanism for charge separation is also discussed.

关键词： Ag2PO4/MoS2 nanocomposite methylene blue degradation efficiency photocatalysis

Integrating one health in national health policies of developing countries: India’s lost opportunities

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Infectious Diseases of Poverty 2016年第1期5卷 799-803页

作者： pranab Chatterjee Manish Kakkar Sanjay Chaturvedi Public Health Foundation of India Plot no 47Sector 44Institutional AreaGurgaon 122002India Department of Community Medicine University College of Medical SciencesAcademicBlock4th FloorDilshad GardenDelhi 110095India

Background:Globally,the threat of infectious diseases,particularly emerging infectious diseases,originating at the human-animal-environment interface,has caught health systems off *** forecasts that future pathogen emergence will be centred in hotspots in Asia,Africa,and Latin America,the need to prepare policy frameworks that can combat this threat is ***:Emergence of diseases such as avian influenza and Ebola virus disease,which threatened social disruption,have established the need for intersectoral coordination/*** events led to the initiation of establishing institutionalised collaborative frameworks in India to adopt a One Health approach to disease prevention and ***,the gains made in influenza control could not be adapted to other infectious *** coordination was briefly carried out,more as a reactive response to *** systemic failure to sustain such efforts have therefore,only undermined a coordinated *** recent draft National Health Policy,2015,has also failed to establish the need for intersectoral coordination in disease control *** the need to endorse linkages between human health,animal health and husbandry,agriculture,and environmental sectors,has led to duplicative and weak response *** absence of health impact assessment with respect to the development agenda in policies,has cast negative effects on the health and wellbeing of man,animal,and the *** of attention to building core capacity in these critical sectors has further raised challenges in designing and deploying mitigation *** developing countries like India being home to a major portion of the world’s poorest livestock farmers,the absence of a policy discourse that endorses the One Health approach in development and health policies is a major hurdle in eliminating poverty and poverty-related ***:The adoption of One Health approaches in health

关键词： One Health Emerging infectious diseases Health Policy Zoonoses Intersectoral coordination Multidisciplinary Transdisciplinary