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排序方式: 共有1222条查询结果,搜索用时 15 毫秒
61.
Silicon - This paper presents the analytical approximation of device physics of heterojunction based double gate (DG) Tunnel field effect transistors (TFETs) in terms of potential distribution,... 相似文献
62.
63.
Kiran Tiwari Rudramani Singh Vinai Kumar Singh Manoj Kumar Krishnamoorthi S. Kumar Krishna 《Iranian Polymer Journal》2020,29(7):615-623
Iranian Polymer Journal - In our recent work, we have reported on hydrogels devoid of cross-linkers. After observing the successful swelling and water retention properties, we have introduced... 相似文献
64.
Kiran Kousar Thomas Ljungdahl Alexander Wetzel Michael Dowhyj Hans Oskarsson Alex S. Walton Monika S. Walczak Robert Lindsay 《Journal of surfactants and detergents》2020,23(1):225-234
An optimized one-pot recipe has been developed to synthesize a surfactant molecule, referred to as OMID, consisting of an imidazoline head group and aliphatic tail, which is an exemplar corrosion inhibitor for carbon steel in acidic solutions. As evidenced by gas chromatography, 1H and 13C nuclear magnetic resonance, and Fourier-transform infrared data, a high-purity product was achieved without the use of either a solvent or catalyst. Critical micelle concentration values and corrosion inhibition efficiencies ( η %) were determined in aqueous solutions of hydrochloric acid and sulfuric acid using surface tensiometry and linear polarization resistance measurements, respectively. Hydrolysis of the imidazoline head group as a function of pH (0–11) was explored with ultraviolet–visible absorption spectroscopy. In addition, N 1s and C 1s X-ray photoelectron spectroscopy data were acquired from both surface-adsorbed OMID and a multilayer of the imidazoline head group of OMID. These latter data are highly relevant to those attempting to understand OMID inhibition chemistry. 相似文献
65.
Casein and soybean are superior quality proteins; however, these are known to inhibit mineral absorption. These investigations were aimed at enzymatic modification of these proteins and to study their effect on mineral bioaccessibility. Casein and soybean proteins were hydrolyzed with alcalase and trypsin individually under optimum conditions. The protein hydrolysates, prepared with different degrees of hydrolysis, were freeze dried, fortified with either iron or zinc and analyzed for bioaccessible minerals in vitro. Proteolytic hydrolysis enhanced the bioaccessibility of iron and zinc in proportion to the degree of hydrolysis. Tryptic hydrolysis enhanced the bioaccessible iron from 1–4% in casein and from 1.3–3.3% in soybean. Alcalase hydrolysis showed a comparatively higher enhancement with both the proteins. Tryptic hydrolysis enhanced zinc bioaccessibity by 3-fold in casein and alcalase hydrolysis enhanced by 2- to 2.5-fold. In soybean, dephytinization showed a synergistic effect. In conclusion, enzymatic hydrolysis of proteins looks promising for enhancing bioaccessibility of minerals in protein matrices. 相似文献
66.
Li Jiang Qi-Xin Xu Mu Qiao Fei-Fei Ma Kiran Thakur Zhao-Jun Wei 《Food science and biotechnology》2017,26(6):1571-1578
Vaccinium bracteatum Thunb, have been widely used in various traditional medicines and food products. The narrow and uniform particle size distribution in V. bracteatum Thunb leaves (VBTL) can be achieved through a new emerging type of foodstuff processing and superfine grinding. The VBTL powders were subjected to four particle sizes as followed: 300–125, 125–75, 75–40, and <40 μm. The VBTL powders were observed to be with smaller size and bulk density, greater surface area, tapped density and the angle of repose. Water solubility index, water holding capacity and total flavonoid extraction increased slightly with the decrease in particle size. Differential scanning calorimetry showed that the VBTL exhibiting particle size of <40 μm had the lowest peak temperature; whereas, powder with a particle size of 125–300 μm displayed the largest endothermic enthalpy. Our results of the properties of VBTL superfine powder supplied the basis for VBTL in potential industrial applications of foods. 相似文献
67.
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
68.
Y. Kalyana Lakshmi K. Srinivas B. Sreedhar M. Manivel Raja M. Vithal P. Venugopal Reddy 《Materials Chemistry and Physics》2009,113(2-3):749-755
With a view to understand the influence of nano size on various properties of cobalt-doped ZnO-based diluted magnetic semiconductors, a series of materials were prepared by the citrate gel route. The phase and morphology studies have been carried out by X-ray diffraction and transmission electron microscopy, respectively. All the samples of the present investigation are found to have hexagonal wurtzite structure and crystallite sizes are found to vary from 25 nm to 65 nm. From the optical absorption measurements it has been observed that upon doping with cobalt, the energy band gap is found to shift towards lower energy side (red shift) while it shifts towards higher energy side (blue shift) when the crystallite size is increased continuously. It has been observed from the XPS results that oxidation state of Cobalt is +2 and that the difference in binding energies of Co 2p3/2 and Co 2p1/2 is found to increase continuously with increasing crystallite size. Finally, all the samples are found to exhibit room temperature ferromagnetism and the specific magnetization decreases with increasing crystallite size. 相似文献
69.
The focus of this paper is to automatically segment and label continuous speech signal into syllable-like units for Indian
languages. In this approach, the continuous speech signal is first automatically segmented into syllable-like units using
group delay based algorithm. Similar syllable segments are then grouped together using an unsupervised and incremental training
(UIT) technique. Isolated style HMM models are generated for each of the clusters during training. During testing, the speech
signal is segmented into syllable-like units which are then tested against the HMMs obtained during training. This results
in a syllable recognition performance of 42·6% and 39·94% for Tamil and Telugu. A new feature extraction technique that uses
features extracted from multiple frame sizes and frame rates during both training and testing is explored for the syllable
recognition task. This results in a recognition performance of 48·7% and 45·36%, for Tamil and Telugu respectively. The performance
of segmentation followed by labelling is superior to that of a flat start syllable recogniser (27·8%and 28·8%for Tamil and
Telugu respectively). 相似文献
70.
In BCC crystals, such as Tungsten (W), slippage has been observed on the (1 1 0) and (1 1 2) planes. In this work, hydrogen diffusion paths from three different W surfaces ((1 0 0), (1 1 0) and (1 1 2)) have been calculated using first principles density functional theory. Equilibrium sites for H at the surfaces are identified. The energetics for H penetration from the surfaces to the solute site in the bulk is calculated. It is found that for our low surface coverage of H (3.4 × 1014 H/cm2), approximately 2 eV is required for an H atom to penetrate any of the W surfaces considered in this study. 相似文献