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Two-Stent Strategy for Bifurcation Lesions in Percutaneous Transluminal Coronary Angioplasty: Real-World Evidence

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World Journal of Cardiovascular Diseases 2024年第3期14卷 140-156页

作者： Dilip kumar Amit Malviya Animesh Mishra rabin Chakraborty Sanjeev S. Mukherjee Soumya Patra Arindam Pande Rana Rathor Roy Debopriyo Mondal Ashesh Halder Sumit Shanker Medica Superspecialty Hospital 127 Eastern Metropolitan Bypass Nitai Nagar Mukundapur Kolkata West Bengal India North Eastern Indira Gandhi Regional Institute of Health & Medical Sciences (NEIGRIHMS) Mawdiangdiang Shillong Meghalaya India

Background: Bifurcation lesions pose a high risk for adverse events after percutaneous coronary intervention (PCI). Evidence supporting the benefits of the two-stent strategy (2SS) for treating coronary bifurcation lesions in India is limited. This study aimed to evaluate the clinical outcomes of various 2SSs for percutaneous transluminal coronary angioplasty for bifurcation lesions in India. Materials and Methods: This retrospective, observational, multicentric, real-world study included 64 patients over 8 years. Data on demographics, medical history, PCI procedures, and outcomes were recorded. Descriptive statistics were computed using the SPSS software. Results: Patients (n = 64) had an average age of 65.3 ± 11.1 years, with 78.1% males. Acute coronary syndrome was reported in 18.8%, chronic stable angina in 40.6%, and unstable angina in 34.4% of participants. Two-vessel disease was observed in 98.4% of patients, and 99.4% had true bifurcation lesions. The commonly involved vessels were the left anterior descending artery (50%), left circumflex coronary artery (34.4%), and first diagonal artery (43.8%). Mean percent diameter stenosis was 87.2% ± 10.1%. The mean number of stents used was 2.00 ± 0.34. The 2SS techniques included the T and small protrusion (TAP) (39.1%), double kissing (DK) crush (18.8%), and the culotte techniques (14.1%). Procedural and angiographic success rate was 92.18%. Major adverse cardiovascular events at 1-year follow-up occurred in 7.8% of cases. Conclusion: The 2SS for bifurcation lesions showed favorable in-hospital and follow-up outcomes. Findings can serve as a resource for bifurcation angioplasty in India. Larger real-world studies with robust methodology are needed to validate these results.

关键词： Bifurcation Stenting Coronary Bifurcation Lesions Percutaneous

Comparative investigation towards machinability improvement in hard turning using coated and uncoated carbide inserts： part Iexperimental investigation

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Advances in Manufacturing 2018年第1期6卷 52-70页

作者： Ramanuj kumar Ashok kumar Sahoo Purna Chandra Mishra rabin kumar Das School of Mechanical Engineering Kalinga Institute of Industrial Technology BhubaneswarOdisha 751024 India

The investigation of low cost uncoated andcoated carbide insert in the hard turning of hardened AISID2 steel （≥55 HRC） will definitely open up a new arena asan economical alternative suitable to industrial machiningsectors. Thus, this paper reports the comparative machin-ability assessment for the hard turning of AISI D2 steel（（55 ± 1） HRC） by coated and uncoated carbide insert in adry environment. Micro hardness and abrasion tests werecarried out to assess resistance capability against wear. Theabove test results confirmed the greater wear resistanceability of AIaO3 coated carbide insert over uncoated car-bide. Based on the extensive investigation of comparativemachinability, the coated carbide insert （TiN-TiCN-A12O3）outperformed the uncoated carbide insert with regard tosurface roughness, flank wear, chip-tool interface temper-ature, and chip morphology. Abrasion and diffusion wereobserved as the principal tool wear mechanisms in theinvestigated range. The uncoated carbide failed completelydue to the severe chipping and quick dulling of the cuttingedge, which led to its unsuitability for machining hardenedsteel.

关键词： Coated and uncoated carbide Hard turning Machinability Flank wear Surface roughness Chipmorphology Cutting temperature

Comparative study on machinability improvement in hard turning using coated and uncoated carbide inserts： part II modeling, multi-response optimization, tool life, and economic aspects

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Advances in Manufacturing 2018年第2期6卷 155-175页

作者： Ramanuj kumar Ashok kumar Sahoo Purna Chandra Mishra rabin kumar Das School of Mechanical Engineering Kalinga Institute of Industrial Technology Bhubaneswar-24 Odisha India

The present study focused on mathematical modeling, multi response optimization, tool life, and eco- nomical analysis in finish hard turning of AISI D2 steel （（55 4- 1） HRC） using CVD-coated carbide （TiN/TiCN/ A1203） and uncoated carbide inserts under dry environ- mental conditions. Regression methodology and the grey relational approach were implemented for modeling and multi-response optimization, respectively. Comparative economic statistics were carried out for both inserts, and the adequacy of the correlation model was verified. The experimental and predicted values for all responses were very close to each other, implying the significance of the model and indicating that the correlation coefficients were close to unity. The optimal parametric combinations for A1203 coated carbide were dl-fl-v2 （depth of cut = 0.1 mm, feed = 0.04 mm/r and cutting speed = 108 m/min）, and those for the uncoated tool were dl-（0.1 mm）-fl （0.04 mm/r）-vl （63 rn/min）. The observed tool life for the coated carbide insert was 15 times higher than that for the uncoated carbide insert, considering flank wear criteria of 0.3 mm. The chip volume after machining for the coated carbide insert was 26.14 times higher than that of the uncoated carbide insert and could be better utilized for higher material removal rate. Abrasion, diffusion, notch- ing, chipping, and built-up edge have been observed to be the principal wear mechanisms for tool life estimation. Use of the coated carbide tool reduced machining costs by about 3.55 times compared to the use of the uncoated carbide insert, and provided economic benefits in hard turning.

关键词： Machinability Hard turning Regression Grey relational analysis Tool life Economic analysis

Wind energy as a source of green hydrogen production in the USA

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Clean Energy 2023年第1期7卷 8-22页

作者： Ashish Sedai rabin Dhakal Shishir Gautam Bijaya kumar Sedhain Biraj Singh Thapa Hanna Moussa Suhas Pol National Wind Institute Texas Tech UniversityLubbockTX 79401USA Department of Mechanical Engineering Texas Tech UniversityLubbockTX 79401USA Department of Mechanical Engineering Tribhuvan UniversityPurbanchal CampusDharanNepal Green Hydrogen Lab Department of Mechanical EngineeringKathmandu UniversityDhulikhelNepal Wind Energy Program Texas Tech UniversityLubbockTX 79401USA

The study incorporates an overview of the green hydrogen-production potential from wind energy in the USA,its application in power generation and the scope of substituting grey and blue hydrogen for industrial *** 10 million metric tons of grey and blue hydrogen is produced in the USA annually to fulfil the industrial demand,whereas,for 1 million metric tons of hydrogen generated,13 million metric tons of CO_(2) are released into the *** research aims to provide a state-of-the-art review of the green hydrogen technology value chain and a case study on the production of green hydrogen from an 8-MW wind turbine installed in the southern plain region of *** research estimates that the wind-farm capacity of 130 gigawatt-hours is required to substitute grey and blue hydrogen for fulfilling the current US annual industrial hydrogen demand of 10 million metric *** study investi-gates hydrogen-storage methods and the scope of green hydrogen-based storage facilities for energy produced from a wind *** research focuses on the USA’s potential to meet all its industrial and other hydrogen application requirements through green hydrogen.

关键词： green hydrogen wind energy electrolysis greenhouse gases

Micelle Mediated Extraction of Iron and Its Determination in Geological, Geochemical, Hydrogeochemical, Biogeochemical and Process Solutions

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American Journal of Analytical Chemistry 2012年第5期3卷 339-346页

作者： Pranab kumar Tarafder rabin kumar Mondal Regional Centre for Exploration and Research AMDER/Department of Atomic Energy Jamshedpur India

Iron irrespective of its valency states forms bluish 1:1 cationic, bluish-violet 1:3 neutral and purple 1:3 anionic complexes with 2,3-dihydroxynaphthalene, at pH 2 - 3, 4 - 5 and 8 - 10, respectively. The cationic bluish complex is highly insensitive and not extractable in organic solvents. Similarly, the bluish violet 1:3 neutral complex is of moderate sensitivity, and it is extractable in organic solvents with reduced sensitivity. The purple 1:3 anionic complex is as such not extractable in any organic solvents. However, in the surfactant medium of the cationic surfactant, cetyltrimethylammonium bromide it is extractable in organic solvents with enhanced sensitivity. The 1:3 anionic complex which is extractable in organic solvents as an ion associate in the presence of cetyltrimethyl ammonium bromide is chosen for application to Silicate rocks, Minerals, Soils, Stream sediments, Concentrates, Tobacco leaves, Cigarettes and Waters, for accurate and sensitive determination of iron owing to facile extraction of iron, enhanced sensitivity high selectivity and better reproducibility of results. The present paper describes a systematic study on the development of an extraction spectrophotometric method for the determination of iron in samples of diverse matrices.

关键词： 2 3-Dihydroxynaphthalene Cetyltrimethylammonium Ion Spectrophotometric Solvent Extraction Determination

Micelle Mediated Extraction of Iron and Its Determination in Geological, Geochemical, Hydrogeochemical,Biogeochemical and Process Solutions

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