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Rewari Sonam Nath Vandana Haldar Subhasis Deswal S. S. Gupta R. S. 《Microsystem Technologies》2019,25(5):1537-1546
Microsystem Technologies - In this paper a cylindrical Dual Metal (DM) Dielectric Engineered (DE) Gate All Around (GAA) MOSFET has been proposed to resolve a big issue of Gate Inducted Drain... 相似文献
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This paper measures carbon-sensitive efficiency and productivity growth in technologically heterogeneous coal-fired thermal power plants in India for the period of 2000 to 2013. It uses a unique data set of 56 plants, obtained petitioning the Right to Information Act 2005. We apply ‘within-MLE’ fixed effects stochastic frontier model to get consistent estimates of meta-directional output distance function. The thermal power plants are grouped into two categories: central sector and state sector. We find that the state sector plants have higher potential to simultaneously increase electricity generation and reduce carbon emissions than the central sector plants. If all the state and central sectors plants were made to operate on the meta-frontier, reduction of 98 million tonnes of CO2 could have been achieved. Carbon-sensitive productivity growth in the central sector plants is higher than the plants in state sector, though in both the sectors productivity growth is governed by carbon-sensitive innovation effect. Commercialisation or autonomy in electricity generation also induces carbon-sensitive productivity growth and reduces carbon-sensitive productivity growth gap. 相似文献
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《Ceramics International》2020,46(3):3015-3022
Ho3+ and Yb3+ codoped bismuth titanate (BTO) composite powders with infrared to visible upconversion luminescence (UCL) function were prepared by SGC method. The effects of Ho3+ and Yb3+ doping content on the structure and property were investigated for BTO: xHo, 0.2 Yb (x = 0, 0.02, 0.04, 0.06, 0.08, 0.1) and BTO: 0.02Ho, yYb (y = 0.1, 0.2, 0.3, 0.5, 0.7, 0.9) samples. All the samples include three bismuth titanate phases (Bi4Ti3O12, Bi2Ti2O7, and Bi20TiO32), and the phase proportion can be tuned by changing Ho3+ and Yb3+ doping content. These powders are well crystalized with honeycomb-like microscopic structure, and with good absorption for 233 nm, 310 nm and 975 nm wavelength. The band gap can be tuned from 3.53 eV to 4.03 eV when increasing Yb3+ content from y = 0 to y = 0.9. A strong 530–580 nm green emission band and a relative weak 630–690 nm red one corresponding to Ho3+: 5S2 → 5I8 and 5F5 → 5I8 transitions appear in the UCL spectra for all the BTO: Ho, Yb samples when pumped at 980 nm. The emission intensities can well be tuned with various Ho3+ and Yb3+ content. The optimal UCL was obtained in BTO: 0.02Ho, 0.5 Yb for all the prepared samples. The energy transfer mechanism is analyzed by building a two-photon energy transfer model, which is proved by the relationship between emission intensities and pumping power measurement. The concentration quenching of Ho3+ is caused by cross relaxation of CR1 and CR2 (Ho: 5F4, 5S2 + 5I8 → 5I4 + 5I7) and by CR3 (Ho: 5F4, 5S2 + Yb: 2F7/2 → Ho: 5I6 + Yb: 2F5/2) for Yb3+ quenching. The mean luminescence lifetime (τm) from Ho: 5S2 decreases monotonously with the increase of Ho3+ and Yb3+ content. 相似文献
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Journal of Superconductivity and Novel Magnetism - Dissipation in YBCO polycrystalline bulk samples added with nominally different amounts of silver (0, 5, 15, 25 wt%) has been studied through... 相似文献
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Ankit Khandelwal Rahil Gupta Radhapiyari Laishram K. Chandramani Singh 《Ceramics International》2019,45(8):10371-10379
Conventional solid state sintering method was used to synthesize lead-free (Ba0.91Ca0.09Sn0.07Ti0.93)O3-xHo2O3 (x?=?0, 1.2,1.4,1.6,1.8 and 2.0?mol%) ceramics. The influence on electrical properties of the system as a result of the structural and microstructural changes introduced by the incorporation of rare earth Ho3+ ions has been investigated. The X-ray diffraction analysis reveals that Ho3+ ions completely diffuse into the (Ba0.91Ca0.09Sn0.07Ti0.93)O3 lattice to form a homogeneous solid solution with a pure perovskite structure having tetragonal symmetry. Evidence of Ho3+ substituting Ti4+ via the oxygen vacancy compensation mechanism exists in the range of 0–1.6?mol % Ho content, while the self-compensation mode is the preferred mechanism beyond 1.6?mol %. The average grain size exhibits a drastic reduction from 16?μm to 0.7?μm as the Ho content increases from 0 to 1.6?mol%, followed by a slight increase at higher Ho concentration. It suggests that addition of Ho3+ inhibits grain growth in the ceramics. In the composition range studied, increasing Ho3+ content produces a gradual decrease in the relative density from 93% to 81%, room temperature dielectric constant (εrt) from 3997 to 807, electromechanical coupling factor (kp) from 0.23 to 0.06, and piezoelectric charge constant (d33) from 102 to 38?pC/N. This degradation in the properties is attributed to the crystalline and microstructural changes driven by the increasing presence of Ho content in the ceramics. 相似文献
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本文详述了红外反射隔热涂料的国内外研究进展,指出了该领域全色系、多功能、智能变色三个研发切入点,提出彩色及深色建筑涂料市场存在巨大缺口,并认为红外反射隔热填料与红外反射颜料、色浆等技术的结合是建筑涂料未来的发展趋势。 相似文献
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本文建立了利用高效液相色谱法定量分析2-甲氧基苯胺甲烷磺酸的方法。通过对流动相等色谱条件的优化,确定了本方法的实验条件,采用峰面积外标法进行了定量。对该方法的准确度、精密度及响应值的线性范围进行了测定,验证了该方法的可行性。 相似文献
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