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排序方式: 共有679条查询结果,搜索用时 9 毫秒
91.
Vinjamuri R. Bishoyi B. D. Sabat R. K. Kumar M. Sahoo S. K. 《Metallurgical and Materials Transactions A》2022,53(6):2146-2162
Metallurgical and Materials Transactions A - Free-end torsion tests were conducted for Ti6Al4V (Ti64) alloy at temperatures of 298 K, 673 K, and 873 K for different strains ranging from 0.22 to... 相似文献
92.
The interfacial tension between the molten metal and the surrounding plasma environment affects the circulation of molten
metal in the weld pool, heat transfer, and the eventual structure and properties of the weld metal. Since the effect of plasma
on the interfacial tension of molten metals is not known, interfacial tension values between low pressure argon plasma and
pure copper and iron were measured. The variables studied were temperature and the intensity of plasma emission. 相似文献
93.
Kuldeep Chouhan Mukesh Yadav Ranjeet Kumar Rout Kshira Sagar Sahoo NZ Jhanjhi Mehedi Masud Sultan Aljahdali 《计算机系统科学与工程》2023,45(2):1113-1128
Twitter is a radiant platform with a quick and effective technique to analyze users’ perceptions of activities on social media. Many researchers and industry experts show their attention to Twitter sentiment analysis to recognize the stakeholder group. The sentiment analysis needs an advanced level of approaches including adoption to encompass data sentiment analysis and various machine learning tools. An assessment of sentiment analysis in multiple fields that affect their elevations among the people in real-time by using Naive Bayes and Support Vector Machine (SVM). This paper focused on analysing the distinguished sentiment techniques in tweets behaviour datasets for various spheres such as healthcare, behaviour estimation, etc. In addition, the results in this work explore and validate the statistical machine learning classifiers that provide the accuracy percentages attained in terms of positive, negative and neutral tweets. In this work, we obligated Twitter Application Programming Interface (API) account and programmed in python for sentiment analysis approach for the computational measure of user’s perceptions that extract a massive number of tweets and provide market value to the Twitter account proprietor. To distinguish the results in terms of the performance evaluation, an error analysis investigates the features of various stakeholders comprising social media analytics researchers, Natural Language Processing (NLP) developers, engineering managers and experts involved to have a decision-making approach. 相似文献
94.
International Journal of Coal Science & Technology - Increasing production and disposal of coal fly ash (CFA) is a matter of serious environment concern. However, CFA contains various... 相似文献
95.
96.
We consider a nonstatic, spin-polarized cylindrically symmetric perfect fluid distribution in the Einstein-Cartan theory and obtain the field equations. These field equations are solved using the Ray–Smalley energy-momentum tensor. 相似文献
97.
Shi W Zeng H Sahoo Y Ohulchanskyy TY Ding Y Wang ZL Swihart M Prasad PN 《Nano letters》2006,6(4):875-881
We describe and demonstrate a general strategy for engineering binary and ternary hybrid nanoparticles based on spontaneous epitaxial nucleation and growth of a second and third component onto seed nanoparticles in high-temperature organic solutions. Multifunctional hybrid nanoparticles that combine magnetic, plasmonic, and semiconducting properties and that are tunable in size and morphology can be realized, as demonstrated for combinations of Au, Fe3O4 and PbS or PbSe. The properties of each component within the hybrids can be modulated strongly by the conjugating component(s) aided by the coherent interfaces between them. 相似文献
98.
Tripathi RM Jha VN Sahoo SK Sethy NK Shukla AK Puranik VD Kushwaha HS 《Radiation protection dosimetry》2012,148(2):211-218
Ground water is the principal source of drinking water in the rural areas of India. With the aim of determining, the contribution of (226)Ra to natural background radiation through drinking water exposure pathway near an operating uranium mining industry at Jaduguda, Jharkhand state of eastern India, the (226)Ra activity concentrations were measured in potable ground water. The water analysed, both tube well and well water, was collected in areas near the uranium industry and away. The (226)Ra concentration was measured by emanometric technique. The (226)Ra level in ground water was ranging between minimum detection limit of 3.5 mBq l(-1) and a maximum of 208 mBq l(-1). The analysis of variance reveals that there is insignificant statistical variation in the median (226)Ra concentration up to a distance of >10 km from the mining complex. Variation in concentration of (226)Ra in sources is attributed to the local geochemistry and environmental factors. The (226)Ra concentration was significantly elevated in natural artesian wells in the vicinity of uranium mineralised hill and it varies from 53.4 to 754 mBq l(-1). The WHO [Guidelines for Drinking Water Quality. Third Edition, Vol. 1, Recommendation (2004)] guideline value of 1000 mBq l(-1) has not been exceeded in any of the sources investigated. 相似文献
99.
Doping effect of polyaniline/MWCNT composites on capacitance and cyclic stability of supercapacitors
Karthikeyan G Sahoo S Nayak GC Das CK 《Journal of nanoscience and nanotechnology》2012,12(3):2704-2710
Polyaniline doped by Zn2+ ions was synthesized as nanocomposites with multiwalled carbon nanotubes (MWCNT) by in-situ oxidative polymerization and investigated as electrode material for supercapacitors. The uniform coating of polyaniline on MWCNT was characterized by field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM). The effect of Zn2+ ions on nanocomposites were characterized by Fourier transform infrared (FTIR) spectroscopy. The electrochemical performances were investigated by cyclic voltammetry (CV), constant current charging/discharging cyclic test (CC) and electrochemical impedance spectroscopy (EIS) using a three-electrode system. The doped polyaniline composites show higher specific capacitance and better cyclic stability. 相似文献
100.
Cheng HK Sahoo NG Khin TH Li L Chan SH Zhao J Juay YK 《Journal of nanoscience and nanotechnology》2010,10(8):5242-5251
Multi-walled carbon nanotubes (MWCNTs) were carboxyl-functionalized in order to improve their dispersion in a polymer matrix. The carboxyl-functionalized MWCNTs (i.e., MWCNT-COOH) were added into a blend matrix consisting of polyamide 6 (PA6) and liquid crystalline polymer (LCP) (PA6:LCP = 80:20 in weight) to make ternary composites. The effects of MWCNT-COOH on the rheological, physical, morphological, thermal, mechanical, and electrical properties of the ternary composites have been examined systematically. The dispersion of MWCNTs in the polymer matrix and their interactions with the polymers (i.e., PA6 and LCP) were found to be the most important factors affecting all properties. The functionalization of MWCNTs resulted in the significant improvement in their dispersion in the polymer matrix and largely enhanced the interactions of MWCNTs with the polymer matrix. The functionalized MWCNTs acted not only as reinforcement fillers but also as a compatibilizer that could enhance the interfacial adhesion between PA6 and LCP. Interestingly, the packing density of the polymer matrix was greatly increased by adding MWCNT-COOH. 相似文献