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排序方式: 共有1160条查询结果,搜索用时 31 毫秒
71.
Sukhdeep Kaur Sukhleen Bindra Narang Deep Kamal Kaur Randhawa 《Journal of Electronic Materials》2018,47(11):6467-6475
In this paper, the thermoelectric performance of porous armchair graphene nanoribbons under tensile and compressive strain is investigated as a function of pore morphology and temperature. For all the porous structures irrespective of their pore size, the performance improves at a compressive strain of 10%, while for tensile nature, the minimum cut-off strain required for improved thermoelectric figure of merit (ZT) shows an inverse relation with the pore size. In addition, optimal pore shape geometry can yield better performance, even at lower values of strain. Further analysis reveals that tensile strain is not able to improve the performance at low and intermediate temperatures of around 300 K, whereas tensile/compressive strain is effective in enhancing the performance of porous armchair graphene nanoribbons at higher temperatures. Furthermore, the structures are found to be more sensitive to compressive strain than the tensile one since the effect of compressive strain is found to improve ZT more significantly. Our analysis based on Non-Equilibrium Green’s function calculations suggests a possible route for tailoring the functionality of nanomaterials so as to achieve great potentials for thermoelectric applications at various temperatures. 相似文献
72.
Monika Choudhary Jasvinder Kaur Sangha Kiran Grover 《Journal of the American Oil Chemists' Society》2014,91(2):179-206
The Indian dietary pattern has undergone major changes over the past 40 years. Many of these changes involve modification in dietary intake of fats and oils. In developing countries like India, vegetable oils are replacing animal fats because of the cost and health concerns. A wide range of vegetable oils are available in the market but the choice of healthy cooking oil has been a controversial subject since ideas keep on changing as new evidence accumulates. One of the factors holding back the increased use of value-added healthy oils in India is that most potential consumers are genuinely not aware of their health benefits. Edible oil consumption is primarily a community-driven phenomenon in India. The purpose of this paper is to highlight the current scenario of edible oils in India, their composition, health benefits, food applications, stability issues and future aspects as buying the right oil for health has become of great importance. 相似文献
73.
R. R. Kaur D. R. Swinbourne M. W. Wadsley C. Nexhip 《Metallurgical and Materials Transactions B》2011,42(3):451-459
The cost of maintaining and eventually replacing refractories as a result of slag attack is a significant cost component in
the copper industry. Converting matte to blister copper takes place in reactors lined with direct-bonded magnesia-chrome refractories,
and several continuous converting operations use calcium ferrite slag. Unfortunately, the low viscosity of calcium ferrite
slag makes it aggressive toward the refractories. Ferrous calcium silicate (FCS) slag has been proposed as a replacement;
however, the effect of this slag on magnesia-chrome refractories has not been studied. In this work, the interactions between
FCS slag and magnesia-chrome refractory at 1573 K (1300 °C) with an oxygen partial pressure of 10−6 atm were studied and compared with that experienced with calcium ferrite slag under the same conditions. Both slags penetrated
the pores in the refractory and caused compositional change in the chromite spinel intergranular bonding phase through cation
interdiffusion, which resulted in cracking and debonding of periclase grains. It was observed that the refractory was penetrated
much more deeply by calcium ferrite slag than FCS slag because of the higher surface tension and lower viscosity of calcium
ferrite slag. As a result, the refractory was attacked less by FCS slag than it was by calcium ferrite slag. It is concluded
that the use of FCS slag in continuous copper converting is likely to extend refractory life. 相似文献
74.
Abstract Radio Frequency Identification (RFID) technology can be applied to a number of pharmaceutical processes, as ample of information can be stored and read rapidly from an RFID tag. Applications may range from inventory control, to access control, to telemedicine, to supply chain management and, most importantly, in combatting counterfeit products. Overall health care services can be improved by using this technology. This technology is gaining popularity in various fields, but is still costly and regulatory considerations are restricting its use. This paper explains the basics of RFID technology and some potential applications related to the pharmaceutical industry. 相似文献
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78.
Rapid detection and quantification of soya bean oil and common sugar in bovine milk using attenuated total reflectance–fourier transform infrared spectroscopy 下载免费PDF全文
Pranita Jaiswal Shyam Narayan Jha Jaspreet Kaur Ramya Hg 《International Journal of Dairy Technology》2018,71(2):292-300
Attenuated total reflectance–Fourier transform infrared spectroscopy, along with chemometrics, were used to detect and quantify soya bean oil (SO) and sugar (CS) adulteration in milk. Bovine milk was artificially adulterated with SO (0.2–2.0%; v/v) and CS (1–10%; w/v) separately. Spectra revealed significant differences in specific wavenumber regions (SO: 1450–1250 cm?1; CS: 1200–900 cm?1). Soya bean oil adulteration was best predicted in wavenumber range of 1262–1164 cm?1, using partial least square regression (coefficient of determination (R2: 0.90 and 0.88 for calibration and validation, respectively). Common sugar adulteration was best predicted in wavenumber range of 1010–910 cm?1 (R2: 0.99 for calibration and validation) using partial least square. 相似文献
79.
Sudhir R. Dave Harjinder Kaur Shobhana K. Menon 《Reactive and Functional Polymers》2010,70(9):692-698
A selective solid-phase extraction procedure using chemically modified Amberlite XAD-4 with monoaza dibenzo 18-crown-6 ether was investigated for the preconcentration and separation of La(III), Nd(III) and Sm(III) in synthetic solution. Before loading samples on synthesized adsorbent adjust pH 4.5 by suitable buffer solution. The adsorbed rare earth elements were eluted by 2 M hydrochloric acid. Various parameters like preconcentration, breakthrough capacity, flow rate were investigated. The limits of detection (n = 5) and limits of quantification (n = 5) for La(III), Nd(III) and Sm(III) were founded 3.9, 4.2 and 7.4 μg L?1 and 13, 15 and 26 μg L?1, respectively. The eluted metal ions were determined by ICP-AES. 相似文献
80.
Solid C60 is known to undergo dimerization under suitable conditions of temperature and pressure. We use a potential model (6-exponential potential) to study the changes leading to the formation of various dimers by hydrostatic pressure on C60 solid at elevated temperatures. We have earlier shown, using Tersoff and Brenner potentials, that a system of two bucky-balls can form a dimer by bonding in different ways, when they start with different orientations at close distances. Based on this, we suggest the required preconditions (P-T curve) for the formation of different dimers from the pristine solid. Stability of the bucky-ball under internal or external pressure has also been studied using Tersoff and Brenner potentials. These two potentials have been compared for their applicability under high pressure conditions as well as for dimerization. We have also estimated the bulk modulus of the bucky-ball at several pressures (under which the molecule remains stable). The values of bulk modulus agree closely with those reported in earlier calculations around zero pressure. When the pressure inside the bucky-ball exceeds 116 GPa, it is seen to break open. This is in close agreement with the findings of molecular dynamics calculations. 相似文献