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Observation of Complex Organic Molecules Containing Peptide-like Bonds Toward Hot Core G358.93-0.03 MM1

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Research in Astronomy and Astrophysics 2024年第7期24卷 181-189页

作者： Arijit manna Sabyasachi Pal Department of Physics and Astronomy Midnapore City CollegePaschim MedinipurWest Bengal721129India

In star formation regions,the complex organic molecules(COMs)that contain peptide bonds(-NH-C(=O)-)play a major role in the metabolic process because-NH-C(=O)-is connected to amino acids(R-CHNH_2-COOH).Over the past few decades,many COMs containing peptide-like bonds have been detected in hot molecular cores(HMCs),hot corinos,and cold molecular clouds,however,their prebiotic chemistry is poorly *** present the first detection of the rotational emission lines of formamide(NH_2CHO)and isocyanic acid(HNCO),which contain peptide-like bonds toward the chemically rich HMC G358.93-0.03 MM1,using high-resolution and high-sensitivity Atacama Large Millimeter/submillimeter Array bands 6 and *** estimate that the column densities of NH_2CHO and HNCO toward G358.93-0.03 MM1 are(2.80±0.29)×10~(15)cm~(-2)and(1.80±0.42)×10~(16)cm~(-2)with excitation temperatures of 165±21 K and 170±32 K,*** fractional abundances of NH_2CHO and HNCO toward G358.93-0.03 MM1 are(9.03±1.44)×10~(-10)and(5.80±2.09)×10^(-9).We compare the estimated abundances of NH_2CHO and HNCO with the existing threephase warm-up chemical model abundance values and notice that the observed and modeled abundances are very *** conclude that NH_2CHO is produced by the reaction of NH_2and H_2CO in the gas phase toward G358.93-0.03 ***,HNCO is produced on the surface of grains by the reaction of NH and CO toward G358.93-0.03 *** also find that NH_2CHO and HNCO are chemically linked toward G358.93-0.03 MM1.

关键词： ISM individual objects(G358.93-0.03)-ISM abundances-ISM kinematics and dynamics-stars formation-astrochemistry

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Intelligent Design of High Strength and High Conductivity Copper Alloys Using Machine Learning Assisted by Genetic Algor

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Computers, Materials & Continua 2024年第4期79卷 1727-1755页

作者： Parth Khandelwal Harshit Indranil manna Metallurgical&Materials Engineering Department Indian Institute of TechnologyKharagpurWest Bengal721302India Computer Science&Engineering Department Indian Institute of TechnologyKharagpurWest Bengal721302India Vice Chancellor Office Birla Institute of Technology(BIT)MesraRanchiJharkhand835215India

Metallic alloys for a given application are usually designed to achieve the desired properties by devising experimentsbased on experience, thermodynamic and kinetic principles, and various modeling and simulation ***, the influence of process parameters and material properties is often non-linear and non-colligative. Inrecent years, machine learning (ML) has emerged as a promising tool to dealwith the complex interrelation betweencomposition, properties, and process parameters to facilitate accelerated discovery and development of new alloysand functionalities. In this study, we adopt an ML-based approach, coupled with genetic algorithm (GA) principles,to design novel copper alloys for achieving seemingly contradictory targets of high strength and high electricalconductivity. Initially, we establish a correlation between the alloy composition (binary to multi-component) andthe target properties, namely, electrical conductivity and mechanical strength. Catboost, an ML model coupledwith GA, was used for this task. The accuracy of the model was above 93.5%. Next, for obtaining the optimizedcompositions the outputs fromthe initial model were refined by combining the concepts of data augmentation andPareto front. Finally, the ultimate objective of predicting the target composition that would deliver the desired rangeof properties was achieved by developing an advancedMLmodel through data segregation and data *** examine the reliability of this model, results were rigorously compared and verified using several independentdata reported in the literature. This comparison substantiates that the results predicted by our model regarding thevariation of conductivity and evolution ofmicrostructure and mechanical properties with composition are in goodagreement with the reports published in the literature.

关键词： Machine learning genetic algorithm solid-solution precipitation strengthening pareto front data augmentation

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

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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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Effect of process parameter on the flowability of nanocrystalline CoNiCrAlY powder synthesized by mechanical milling

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Particuology 2024年第9期92卷 210-223页

作者： Annadaa Shankara Dash Indranil manna Deepa Devapal Sharad Chandra Sharma Jyotsna Dutta Majumdar School of Nanoscience and Technology IIT KharagpurWest BengalIndia BIT Mesra RanchiJharkhandIndia Department of Metallurgical and Materials Engineering IIT KharagpurWest BengalIndia Vikram Sarabhai Space Centre ThiruvanthapuramKeralaIndia

The present study concerns understanding the effect of process parameters on the characteristics and flowability of nanocrystalline CoNiCrAlY powder synthesized by mechanical *** milling has been conducted in a planetary ball mill with tungsten carbide(WC)ball,with ball to powder ratio of 10:1 at 300 rpm speed,using 1%stearic acid and toluene as process control agent(PCA)with time varying from 10 h to 36 *** synthesized nanocrystalline powder were characterized by Scanning Electron Microscopy,X-ray Diffraction technique,X-ray Photoelectron Spectroscopy,and Differential Scanning ***,flowability in terms of Hausner ratio was assessed by Tap Density *** particle size of the powder was found to decrease from 33μm to 22μm after 10 h of milling and further increases to 43μm and 38μm after 25 and 36 h of milling,respectively,in stearic acid ***,in toluene medium particle size continuously decreases from 33μm to 9.7μm with increasing milling *** particle morphology changes from spherical to platelet shape at low milling hours in both of the *** 25 h of milling,the shape of the particles is nearly spherical for stearic acid and irregular for toluene used as a *** size was found to decrease with increasing milling time from 147 nm to 7.7 nm and to 6.4 nm in stearic acid and toluene media,*** was presence ofγ,γʹ,β,hcp-Co,Al_(2)O_(3)and AlOOH phases on the powder particles milled in both the *** measured Hausner ratio of the powders was found to vary from 1.18 to 1.32 in stearic acid medium,and was found to increase with increasing milling *** the other hand,in toluene media flowability decreases(Hausner ratio increases from 1.33 to 1.44)with increasing milling time.

关键词： Mechanical milling Microstructure Process control agent(PCA) CoNiCrAIY Toluene Stearic acid Flowability

A lightweight and high compressive resistance thermal insulation material with dual-network structure

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Nano Research 2024年第5期17卷 4279-4287页

作者： Mengmeng Yang Zhaofeng Chen Yang Ding Wu Qiong Tianlong Liu manna Li Lixia Yang Sheng Cui School of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites Nanjing Tech UniversityNanjing 211816China

Ceramic fibrous aerogels are highly desirable for thermal management materials due to their high porosity,excellent elasticity,thermal conductivity,and good thermal ***,the fabrication of nanofibrous aerogel with super-elasticity and good shape retention at the same time has remained *** meet the requirements,a novel anisotropy nanofibrous-granular aerogel with a quasi-layered multi-arch-like and hierarchical-cellular structure is designed and prepared by vacuum-filtration-assisted freeze-drying and *** quasi-layered multi-arch and flexible nanofibers endowed the aerogels with excellent mechanical robustness(ultimate stress up to 60 kPa with strain 60%)and super-elasticity with recoverable compression strain up to 60%.The introduced SiO_(2) aerogel nanoparticles and nanofibers are assembled into an arch-like structure and become the connection point of adjacent nanofibers,which endows low thermal conductivity(0.024 mW/(m·K))of composite *** novel strategy provides a fresh perspective for the preparation of nanofibrous aerogel with robust mechanical in thermal insulation and other fields.

关键词： nanofibrous aerogel dual-network structure thermal insulation nanofibrous-granular composite aerogels strong mechanical

Fabrication and evaluation of carboxymethyl guar gum-chitosan interpenetrating polymer network (IPN) nanoparticles for controlled drug delivery

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Medicine in Novel Technology and Devices 2024年第2期22卷 73-79页

作者： Chandrani Roy Arijit Gandhi Sreejan manna Sougata Jana Department of Pharmaceutics Gupta College of Technological SciencesAshram MoreG.T.RoadAsansol713301West BengalIndia Department of Pharmaceutical Technology Brainware UniversityBarasatKolkataWest Bengal700125India Department of Health and Family Welfare Directorate of Health ServicesKolkataIndia

Guar gum(GG)has drawn more interest from researchers in the last several decades for the controlled delivery of *** aim of the research is to fabricate and evaluate an interpenetrating polymer network(IPN)based nanocarriers system employing chemically modified GG to achieve controlled release of *** present study,we have reported the synthesis of carboxymethyl GG-chitosan IPN nanoparticles for controlled release of metformin *** guar gum(CMGG)was synthesized and employed for developing IPN nanoparticles in combination with chitosan in varying polymeric ratios.A cross-linking agent,sodium tripolyphosphate(Na-TPP)was used for the synthesis of IPN colloidal suspension of nanoparticles which was lyophilized to obtain *** carboxymethylation of GG was confirmed through Fourier transform infra-red spec*** mean particle size was 440.6 nm indicating a polydispersity index of *** drug entrapment efficiency was found to vary between 67.461.64%to 88.232.02%.The differential scanning calorimetry study revealed the presence of amorphous metformin hydrochloride as a homogenous dispersion in nanoparticles(NPs)*** vitro drug release study indicated controlled release ability of developed IPN matrix.A2 formulation(chitosan:CMGG-1:1)exhibited 78.110.27%release after 8 *** evaluation performed in alloxan-treated diabetic rat model exhibited a prolonged hypoglycemic efficacy over 6 h,for A2 formulation treated group,compared to the group receiving only metformin HCl,which demonstrated a reduction in blood glucose levels for up to 4 *** study findings demonstrated the efficacy of the CMGG-chitosan based IPN nanoparticulate system for sustained delivery of therapeutic agents.

关键词： Carboxymethyl guar gum Chitosan Interpenetrating polymer network Nanoparticles Controlled release Metformin hydrochloride

生物育种技术面临的法规挑战解析:生物创新与法律碰撞

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分子植物育种 2024年第1期22卷 150-154页

作者：谢曼娜广西警察学院司法应用学院南宁530028

随着生物育种技术的持续进步,该领域与法律法规之间的相互作用越来越受到人们的关注。生物技术的飞速发展带来了巨大的潜力和机会,但同时也引发了一系列的法律挑战。本研究深入探讨了生物育种技术面临的主要法规难题,并分析了这些技术... 详细信息

随着生物育种技术的持续进步,该领域与法律法规之间的相互作用越来越受到人们的关注。生物技术的飞速发展带来了巨大的潜力和机会,但同时也引发了一系列的法律挑战。本研究深入探讨了生物育种技术面临的主要法规难题,并分析了这些技术与现行法律制度之间的碰撞。本研究还讨论了如何在确保技术创新与法律保护之间找到平衡点,以及如何在未来进一步优化法律框架以适应技术发展的需要。本研究对于政策制定者、科研人员和行业从业者了解生物创新与法律之间的复杂关系具有重要意义。

关键词：生物育种技术法律碰撞法规挑战技术创新法律框架

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基于情绪ABC理论的心理护理干预在急性心肌梗死患者中的应用效果

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中外医药研究 2024年第9期3卷 117-119页

作者：吴曼娜贵州医科大学附属医院贵州贵阳550000

目的:分析基于情绪ABC理论的心理护理干预在急性心肌梗死患者中的应用效果。方法:选取2021年2月—2023年2月贵州医科大学附属医院收治的急性心肌梗死患者80例作为研究对象,采用随机数字表法分为观察组和对照组,各40例。对照组采用常规护... 详细信息

目的:分析基于情绪ABC理论的心理护理干预在急性心肌梗死患者中的应用效果。方法:选取2021年2月—2023年2月贵州医科大学附属医院收治的急性心肌梗死患者80例作为研究对象,采用随机数字表法分为观察组和对照组,各40例。对照组采用常规护理,观察组在对照组基础上采用基于情绪ABC理论的心理护理。比较两组焦虑抑郁程度、心功能及心血管事件发生情况。结果:护理后,两组焦虑自评量表、抑郁自评量表评分降低,观察组低于对照组,差异有统计学意义(P<0.05);护理后,两组左室射血分数升高,观察组高于对照组,差异有统计学意义(P<0.05);两组左心室收缩末期内径、左心室舒张末期内径缩小,观察组小于对照组,差异有统计学意义(P<0.05)。观察组心血管事件总发生率低于对照组,差异有统计学意义(P=0.048)。结论:基于情绪ABC理论的心理护理干预在急诊急性心肌梗死患者中的应用效果显著,可减轻患者不良情绪,改善心功能,减少心血管事件发生风险。

关键词：急性心肌梗死心理护理情绪ABC理论急诊

线上线下一体化教学模式实践与探索——以“狱政管理学”课程为例

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科教导刊 2024年第4期 132-134页

作者：谢曼娜广西警察学院司法应用学院广西南宁530022

线上线下一体化教学模式将传统课程教学与在线学习相结合,可以有效提高学生的学习效果和综合素质。为了更好地在“狱政管理学”中实施线上线下一体化教学模式,可以优化教学内容,建立健全线上线下一体化教学管理制度;提高教学质量,培养... 详细信息

线上线下一体化教学模式将传统课程教学与在线学习相结合,可以有效提高学生的学习效果和综合素质。为了更好地在“狱政管理学”中实施线上线下一体化教学模式,可以优化教学内容,建立健全线上线下一体化教学管理制度;提高教学质量,培养具备实践能力和创新精神的专业人才;整合教育资源,加强线上线下教学过程的互动与沟通。

关键词：线上线下一体化狱政管理学教学模式实践与探索

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