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91.
The use of optical interconnects for communication between points on a microchip is motivated by system-level interconnect modeling showing the saturation of metal wire capacity at the global layer. Free-space optical solutions are analyzed for intrachip communication at the global layer. A multiscale solution comprising microlenses, etched compound slope microprisms, and a curved mirror is shown to outperform a single-scale alternative. Microprisms are designed and fabricated and inserted into an optical setup apparatus to experimentally validate the concept. The multiscale free-space system is shown to have the potential to provide the bandwidth density and configuration flexibility required for global communication in future generations of microchips. 相似文献
92.
Diffusion-limited patterning (DLP) is a new technique that enables patterning of labile molecular species in solution phase onto surfaces that are not easily accessible. This technique is self-aligning and is simple to implement for patterning multiple species. We demonstrated DLP by patterning alternating bands of fluorescently labeled and unlabeled streptavidin in biotin-functionalized nanofluidic channels with spatial resolution better than 1 microm. The methodology of DLP also enables experimental measurement of a unique parameter that relates molecular surface grafting density, concentration, diffusivity, and channel geometry. 相似文献
93.
This paper presents the theoretical investigation of CDM opportunity in a township at Jaipur, India. The purpose of study is to identify and analyze the various opportunities viz., installation of solar water heater, energy efficient lighting, energy efficient air conditioners, and energy efficient submersible water pumps in desert coolers and thus achieve a considerable (65.7?%) reduction in GHG emissions. Out of the various opportunities considered, the retrofitting with solar water heater can be recommended for CDM. Though, the retrofitting with energy efficient lighting, energy efficient air conditioners and energy efficient submersible water pumps in desert coolers claimed CO2 emission reduction of 104.84, 25.92, and 36.94?tons per annum, respectively, but the only opportunity which got through CDM was retrofitting with solar water heater claiming 115.70?tCO2 (100?%) emission reductions per annum which could result into net earnings of 115.70 CERs. The simple and discounted payback period for all four project activities are also calculated with and without CDM and tax benefits. 相似文献
94.
The analysis of cell types and disease using Fourier transform infrared (FT-IR) spectroscopic imaging is promising. The approach lacks an appreciation of the limits of performance for the technology, however, which limits both researcher efforts in improving the approach and acceptance by practitioners. One factor limiting performance is the variance in data arising from biological diversity, measurement noise or from other sources. Here we identify the sources of variation by first employing a high throughout sampling platform of tissue microarrays (TMAs) to record a sufficiently large and diverse set data. Next, a comprehensive set of analysis of variance (ANOVA) models is employed to analyze the data. Estimating the portions of explained variation, we quantify the primary sources of variation, find the most discriminating spectral metrics, and recognize the aspects of the technology to improve. The study provides a framework for the development of protocols for clinical translation and provides guidelines to design statistically valid studies in the spectroscopic analysis of tissue. 相似文献
95.
R. K. Bhagat T. R. G. Kutty Arun Kumar Srikumar Banerjee 《Journal of Materials Science》2012,47(7):3177-3184
In order to assess the changes in mechanical properties of Zircaloy cladding at extreme conditions, tensile testing and hardness
measurements were carried out on Zircaloy-2 specimens that were annealed with ThO2–3.45% UO2 at 1200 °C for 15 min. Similar studies were repeated with simulated high burn-up fuel powders based on ThO2–3.45% UO2. The above treatment resulted in increase in hardness and reduction in elongation in Zircaloy-2. This is attributed to the
oxygen embrittlement of Zircaloy-2. 相似文献
96.
Xin HL Mundy JA Liu Z Cabezas R Hovden R Kourkoutis LF Zhang J Subramanian NP Makharia R Wagner FT Muller DA 《Nano letters》2012,12(1):490-497
The thousand-fold increase in data-collection speed enabled by aberration-corrected optics allows us to overcome an electron microscopy paradox: how to obtain atomic-resolution chemical structure in individual nanoparticles yet record a statistically significant sample from an inhomogeneous population. This allowed us to map hundreds of Pt-Co nanoparticles to show atomic-scale elemental distributions across different stages of the catalyst aging in a proton-exchange-membrane fuel cell, and relate Pt-shell thickness to treatment, particle size, surface orientation, and ordering. 相似文献
97.
Saroj Kumari Aadesh P. Singh Sonal Dinesh Deva Rohit Shrivastav Sahab Dass Vibha R. Satsangi 《International Journal of Hydrogen Energy》2010
Nanoporous hematite (α-Fe2O3) thin films doped with Ti4+ deposited by spray-pyrolysis were successfully used in photoelectrochemical splitting of water for solar hydrogen production. X-ray diffraction, field emission scanning electron microscopy, UV–visible absorption and photoelectrochemical studies have been performed on the undoped and Ti4+ doped hematite thin films. Morphology of α-Fe2O3 thin films was observed to be nanoporous, with increased porosity (pore size ∼12 to 20 nm) on increasing doping concentration. A significant decrease in the bandgap energy from 1.95 to 1.27 eV was found due to doping. α-Fe2O3 film doped with 0.02 M Ti4+ ions exhibited best solar to hydrogen conversion efficiency (photoconversion efficiency) of 1.38% at 0.5 V/SCE. Highest photocurrent densities of 0.34 mA/cm2 at zero bias and 1.98 mA/cm2 at 0.5 V/SCE were obtained by incorporating 0.02 M Ti4+ in α-Fe2O3, which are significantly larger than earlier reported values. Donor density (30.8 × 1020 cm−3) and flatband potential (−1.01 V/SCE) obtained were also maximum for this sample. Hydrogen collected in 1 hr at Pt electrode with the best photoelectrode was 2.44 mL with 150 mW/cm2 visible light source. 相似文献
98.
Providing quality of service (QoS) guarantees is important in the third generation (3G) and the fourth generation (4G) cellular networks. However, large‐scale fading and non‐stationary small‐scale fading can cause severe QoS violations. To address this issue, we design QoS provisioning schemes, which are robust against time‐varying large scale path loss, shadowing, non‐stationary small scale fading, and very low mobility. In our design, we utilize our recently developed effective capacity technique and the time‐diversity dependent power control proposed in this paper. The key elements of our QoS provisioning schemes are channel estimation, power control, dynamic channel allocation, and adaptive transmission. The advantages of our QoS provisioning schemes are (1) power efficiency, (2) simplicity in QoS provisioning, (3) robustness against large‐scale fading and non‐stationary small‐scale fading. Simulation results demonstrate that the proposed algorithms are effective in providing QoS guarantees under various channel conditions. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
99.
Anupam Srivastav Pawan Kumar Anuradha Verma York R. Smith Vibha Rani Satsangi Rohit Shrivastav Umesh V. Waghmare Sahab Dass 《International Journal of Hydrogen Energy》2018,43(33):15815-15822
Though bismuth vanadate (BiVO4) is extensively used as a photoactive material, its performance in harnessing solar energy is limited by ineffective separation of photo-excited charge carriers. We demonstrate here a concept of n-n+ homojunction of BiVO4/BiV1-xMnxO4-y, which improves its charge separation efficiency. Using first-principles theoretical calculations, we determine the effect of Mn substitution on oxygen vacancy formation energies and associated changes in the electronic structure of BiVO4. Showing that Mn substitution pushes the Fermi level of BiVO4 towards its conduction band, we predict that the associated enhanced bending of bands at the homojunction (BiVO4/BiV1-xMnxO4-y) facilitates efficient separation of charge carriers. With Mott-Schottky experiments, we verify the increased band bending at the n-n+ homojunction, and show that the maximum photocurrent density measured in a sample with n-n+ homojunction is ten times higher than that obtained of the pristine sample. Secondly, Mn substitution in BiVO4 also reduces the oxygen vacancy formation energy, promoting higher concentration of O-vacancies, further enhancing the photoelectrochemical response. 相似文献
100.
A rectangular plate with inclined cracks of different crack lengths at different crack inclination angles under biaxial loading condition are being analyzed in mixed mode condition using finite element method (FEM) for the determination of stress intensity factors (SIFs). With increases of the width of the plate and the crack length ratio, SIF increases up to 45° of crack inclination angle and then decreases; maximum value is obtained at 45° of crack inclination angle. With the increasing value of size factor, the value of SIF starts decreasing. The accuracy of the results of the proposed method is validated by comparing with the previously obtained results by theoretical and experimental methods. The FEM results give significant result for the two-dimensional mixed mode loading conditions. 相似文献