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排序方式: 共有392条查询结果,搜索用时 15 毫秒
91.
Silicon - In this work, we examined the analog and circuitry amplifying capacity of our novel 3 nm Truncated Fin Junctionless bulk FinFET (n-type) with two different oxide thicknesses at... 相似文献
92.
Silicon - Concerned work is solely dedicated to the optimized characteristics of Nanoscale vacuum channel TF (Truncated fin)-FinFET at gate length of 7 nm. NVCTF-FinFET has its own... 相似文献
93.
In this paper, we report a significant improvement in mechanical properties of near eutectic Nb–Si alloys by addition of Gallium (Ga) and control of microstructural length scale. A comparative study of two alloys Nb-18.79 at.%Si and Nb-20.2 at.%Si–2.7 at.%Ga were carried out. The microstructure refinements were carried out by vacuum suction casting in water cooled thick copper mold. It is shown that addition of Ga suppresses Nb3Si phase and promotes β-Nb5Si3 phase. The microstructural length scale and in particular eutectic spacing reduces significantly to 50–100 nm in suction cast ternary alloys. Compression test shows a strength of 2.8 ± 0.1 GPa and plasticity of 4.3 ± 0.03%. In comparison, the binary Nb-18.79 at.%Si alloy processed under identical conditions exhibit coarser length scale (300–400 nm) and brittle behavior. The fracture toughness of Ga containing suction cast alloy shows a value of 24.11 ± 0.5 MPa√m representing a major improvement for bulk Nb–Si eutectic alloy. 相似文献
94.
95.
96.
We demonstrate a significant reduction in delay sensitivity against temperature in optical fibres, using a novel tight jacketed fibre structure. This technique has the cabability of producing fibre in which the optical delay is insensitive to temperature. This has potential in the field of sensors and fibre devices. 相似文献
97.
98.
V. Moorthy S. Vaidyanathan Baldev Raj T. Jayakumar B. P. Kashyap 《Metallurgical and Materials Transactions A》2000,31(4):1053-1065
The influence of tempering-induced microstructural changes on the micromagnetic parameters such as magnetic Barkhausen emission
(MBE), coercive force (H
c), residual induction (B
r), and maximum induction (B
max) has been studied in 0.2 pct carbon steel, 2.25Cr-1Mo steel, and 9Cr-1Mo steel. It is observed that, after short tempering,
the micromagnetic parameters show more or less linear correlation with hardness, which is attributed to the reduction in dislocation
density, but long-term tempering produces nonlinear behavior. The variation in each of these parameters with tempering time
has been explained based on the changes in the size and distribution of ferrite laths/grains and precipitates. It has been
shown that the individual variation in the microstructural features such as size and distribution of laths/grains and precipitates
during tempering can be clearly identified by the MBE parameters, which is not possible from the hysteresis loop parameters
(H
c and B
r). It is also shown that the MBE parameters can not only be used to identify different stages of tempering but also to quantify
the average size of laths/grains and second-phase precipitates. 相似文献
99.
4D CAD models that integrate physical 3D elements with time, have been used to visualize construction processes in several projects worldwide. 4D models have been used and have been shown to have benefits over processes that span the entire lifecycle of a project such as collaboration with stakeholders, making design decisions, assessing project constructability, identifying spatial conflicts in construction and so on. Despite these benefits, several organizational and project-specific barriers have hindered the widespread adoption of 4D CAD. In order to reconcile the theoretical benefits of 4D models with the practical difficulties faced in implementation, there is an urgent need to explore the implementation of 4D models on construction sites as well as the perceptions of intended users/beneficiaries towards this implementation. This paper aims to address this need and contribute to our understanding of how 4D models must be introduced, positioned and implemented on construction sites, so as to maximize both their acceptability and their usefulness. We describe two 4D models of infrastructure projects and two 4D models of commercial projects that have been built and implemented. Through a process of structured and unstructured interviewing the paper gauges the response of project participants across various organizational levels on each of these projects as to the usefulness of 4D in project planning and control. Through qualitative and statistical analysis of the data we establish that 4D CAD is likely to be most beneficial in the project shaping or planning stage and in the construction stage. In the project shaping stage, 4D CAD is likely to be particularly useful in communicating construction plans and processes to clients, while during the construction phase, 4D CAD is likely to be particularly useful in comparing the constructability of work methods visually in order to detect conflicts or clashes, and as a visual tool for contractors, clients, subcontractors and vendors to review and plan project progress. Further, upper management and site workers are more likely to use and derive benefits from the visualization of processes using 4D given their lack of site related knowledge or skills, while construction professionals who are more construction-savvy are more likely to appreciate and benefit from the analytical and planning aids that 4D simulations provide during the construction phase. However, it is likely that despite these benefits 4D CAD models might not diffuse through the construction industry unless 4D modelling and analysis is integrated into existing project planning approaches. The paper concludes with a brief discussion on future 4D software development that seeks to bring about such integration and leverages the benefits of 4D CAD to bring about improved operational efficiencies on construction sites. 相似文献
100.
Effect of Gd on microstructural, dielectric and electrical properties has been studied over wide temperature (300–500 K) and frequency range (100 Hz–1 MHz). Gd substitution in CCTO system results in decrease in the grain size and increase of Schottky potential barrier which causes lower value of dielectric constant. The dielectric constant remains nearly constant in temperature range 300–350 K. Doped samples show lower dielectric loss in middle frequency range (~10 kHz–1 MHz) at room temperature. The AC conductivity (σac) obeys a power law, σac = Afn, where n is temperature dependent frequency exponent. The AC conductivity behaviour can be divided into three regions depending on conduction processes and the relevant charge transport mechanisms have been discussed. 相似文献