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排序方式: 共有275条查询结果,搜索用时 696 毫秒
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Bahram Rashidi 《International Journal of Circuit Theory and Applications》2020,48(8):1227-1243
In this paper, low-cost and two-cycle hardware structures of the PRINCE lightweight block cipher are presented. In the first structure, we proposed an area-constrained structure, and in the second structure, a high-speed implementation of the PRINCE cipher is presented. The substitution box (S-box) and the inverse of S-box (S-box−1) blocks are the most complex blocks in the PRINCE cipher. These blocks are designed by an efficient structure with low critical path delay. In the low-cost structure, the S-boxes and S-boxes−1 are shared between the round computations and the intermediate step of PRINCE cipher. Therefore, the proposed architecture is implemented based on the lowest number of computation resources. The two-cycle implementation of PRINCE cipher is designed by a processing element (PE), which is a general and reconfigurable element. This structure has a regular form with the minimum number of the control signal. Implementation results of the proposed structures in 180-nm CMOS technology and Virtex-4 and Virtex-6 FPGA families are achieved. The proposed structures, based on the results, have better critical path delay and throughput compared with other's related works. 相似文献
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采用0.5μm标准CMOS工艺和微机械加工工艺,设计并制作了低成本4×4钨微测辐射热计阵列集成芯片。阵列中每个钨微测辐射热计均由微悬桥结构和钨热敏电阻组成,CMOS读出电路集成在阵列下方。微悬桥结构由表面牺牲层技术实现,不需要任何的光刻工艺。钨微测辐射热计像元尺寸为100μm×100μm,填充因子为20%。测试结果表明,在真空环境下,钨微测辐射热计等效热导为1.31×10-4W/K,等效热容为1.74×10-7J/K,热时间常数为1.33 ms。当红外光源的斩波频率为10 Hz时,钨微测辐射热计的电压响应率为1.91×103V/W,探测率为1.88×107cm·Hz1/2/W。 相似文献
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重金属废水处理最新进展 总被引:25,自引:2,他引:25
详细论述了近年来一些处理重金属废水的新方法,并对各种方法进行了综合评述。这些新方法主要有:廉价吸附剂吸附、胶束增强超滤、络合—超滤耦合过程和电化学法。此外,将络合—超滤和电化学法集成起来处理重金属废水,可实现废水回用和重金属回收,因而具有广阔的应用前景。 相似文献
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Zi Li Huifeng Yao Lijiao Ma Jingwen Wang Zhaozhao Bi Shijie Wang Susanne Seibt Tao Zhang Ye Xu Junzhen Ren Yang Xiao Cunbin An Wei Ma Jianhui Hou 《Advanced functional materials》2023,33(26):2300202
Organic solar cells (OSCs) have achieved much progress with rapidly increasing power conversion efficiencies (PCEs). It should be noted that the top-performance OSCs are generally consisted of active materials with complex chemical structures, resulting in high costs. Here, combining the material design and morphology control, high-efficiency OSCs are fabricated by a low-cost donor: acceptor blend. A completely non-fused electron acceptor named Tz is designed and synthesized via introducing thiazole units on both sides of a bithiophene core, which shows an outstanding PCE of 13.3% with a typical polythiophene donor. More importantly, optimization guidelines are presented to get excellent morphology for low-cost donor:acceptor systems. Three polythiophenes are selected, poly(3-hexylthiophene) and its two derivatives with electron-withdrawing substitutions (PDCBT and PDCBT-2F), as donors to fabricate the cell devices. The computational and experimental data reveal that decreasing the electrostatic interaction between polythiophene and Tz is the key to getting a suppressed miscibility and thus a high phase purity. This study provides insight into the molecular design and donor:acceptor matching requirements for high-efficiency and low-cost OSCs. 相似文献
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Using low-cost clay supports as substrates, ceramic–LTA zeolite composite membranes (Z1–Z4) were fabricated with hydrothermal crystallization. The composite membranes were achieved with variations in the sequential zeolite depositional steps. For Z1–Z4 membranes, various characterization techniques such as thermogravimetric (TG), particle size distribution (PSD), X-ray diffraction (XRD), and field emission scanning electron microscopic (FE-SEM) analysis were applied. For the Z1–Z4 membranes, the pure water permeability, porosity, and average pore size varied from 1.22 × 10?7 to 1.19 × 10?8 m3/m2s kPa, 30–23%, and 215–76 nm, respectively. For the Z4 membrane, ultrafiltration experiments were conducted at a pH of 2.5 and transmembrane pressure differential of 207 kPa using aqueous bovine serum albumin (BSA) solutions. The optimal flux and rejection correspond to 4.54 × 10?7 m3/m2s and 80%, respectively. 相似文献
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Abdul Hai Alami Kamilia Aokal Di Zhang Aya Taieb Mohammed Faraj Alya Alhammadi Juveiriah Mohammed Ashraf Bassel Soudan Jinan El Hajjar Mihai Irimia‐Vladu 《国际能源研究杂志》2019,43(11):5824-5833
This paper presents a facile and economic development of dye‐sensitized solar cells using a nonprecious counter electrode made from ball‐milled tellurium‐doped graphene (Te‐Gr) and a natural sensitizer extracted from Calotropis gigantea leaves. The prepared materials were characterized using various techniques, such as Raman spectroscopy, X‐ray diffraction (XRD), atomic force microscopy (AFM), impedance spectroscopy, and scanning electron microscopy with built‐in energy‐dispersive X‐ray spectroscopy (SEM with EDS). The electrochemical activity of the produced counter electrodes and the impedance of the fabricated cells were examined and discussed to devise plans for future enhancement of cell performance. A clear pattern of improvement was found when using cost‐effective Te‐Gr relative to the costly platinum counter electrodes, especially when compared with cells employing another natural sensitizer. The results show approximately 51% enhancement over chlorophyll‐based cells made from spinach, where the added advantage in our approach is the utilization of an abundant plant extract with little nutritional appeal. 相似文献