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81.
M. Aamir I. Bibi S. Ata K. Jilani F. Majid S. Kamal N. Alwadai M.A.S. Raza M. Bashir S. Iqbal M. Aadil M. Iqbal 《Ceramics International》2021,47(12):16696-16707
In the present investigation, La1-xCoxCr1-yFeyO3 (x,y = 0.0, 0.12, 0.36, 0.60) perovskite was fabricated via a facile micro-emulsion route. The synthesized perovskites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) techniques to examine the effect of Co and Fe ions on the physico-chemical properties. The ferroelectric, dielectric, and magnetic properties of La1-xCoxCr1-yFeyO3 were changed significantly as a function of dopants contents (Co and Fe ions). Outcomes revealed that the dielectric, ferroelectric and magnetic properties of LaCrO3 perovskite can be tuned significantly via Co and Fe doping and La0.40Co0.60Cr0.40Fe0.60O3 have potential for photocatalytic dye removal under (visible) light expoure. The photocatalytic activity (PCA) of the pristine LaCrO3 and La0.40Co0.60Cr0.40Fe0.60O3 photocatalyst was evaluated under (visible) light irradiation for crystal violet (CV) dye. Experimental results revealed that La0.40Co0.60Cr0.40Fe0.60O3 photocatalyst degrdae almost 77.21% CV dye with the rate constant value of 0.01475 min?1. In the presence of isopropyl alcohol (IPA) scavenger, the PCA of the La0.40Co0.60Cr0.40Fe0.60O3 photocatalyst and rate constant value of the photocatalytic reaction decreased to 32.5% and 0.00491 min?1, suggesting the superoxide as main active specie. Results revealed that Co and Fe doping doped material is efficient for photocatalytic presentations under solar light expoure. 相似文献
82.
Carbon nanotubes (CNTs) are high-performance materials because of their superior electrical conductivity, thermal conductivity, and self-lubrication, and they have been studied for application to polymer composite materials as fillers. However, the methods of fabricating polymer composites with CNTs, such as injection molding, are too complicated for industrial applications. We propose a simple cold spray (CS) technique to obtain a polymer composite of polyethylene (PE) and CNTs. The composite films were deposited by CS on polypropylene and nano-porous structured aluminum substrates. The maximum thickness of the composite film was approximately 1 mm. Peaks at G and D bands were observed in the Raman spectra of the films. Scanning electron microscopy images of the film surface revealed that PE particles were melted by the acceleration gas and CNTs were attached with melted PE. The PE particles solidified after contact with the substrate. These results indicate that PE–CNT composite films were successfully deposited on polypropylene and nano-porous structured aluminum substrates by CS. 相似文献
83.
In this work, a platinum surface was modified with benzo[c]cinnoline (BCC) to get new insight into the metal modification area. By potential scanning from + 0.4 V to - 0.8 V, the diazotized BCC was reduced electrochemically and grafted onto the platinum electrode surface to form benzo[c]cinnoline modified platinum electrode (Pt-BCC). Electrochemical reduction of benzo[c]cinnoline diazonium salt on the electrode surface yielded a relatively stable organic film. The introduction of BCC molecules onto the platinum surface was verified by cyclic voltammetry, electrochemical impedance spectroscopy, Raman spectroscopy and ellipsometry. The stability and the potential range of the Pt-BCC electrode were also studied. 相似文献
84.
Mohammed Alamgir Hossain Mohammad Osman Tokhi 《国际自动化与计算杂志》2006,3(3):252-262
Although computer architectures incorporate fast processing hardware resources, high performance real-time implementation of a complex control algorithm requires an efficient design and software coding of the algorithm so as to exploit special features of the hardware and avoid associated architecture shortcomings. This paper presents an investigation into the analysis and design mechanisms that will lead to reduction in the execution time in implementing real-time control algorithms. The proposed mechanisms are exemplified by means of one algorithm, which demonstrates their applicability to real-time applications. An active vibration control (AVC) algorithm for a flexible beam system simulated using the finite difference (FD) method is considered to demonstrate the effectiveness of the proposed methods. A comparative performance evaluation of the proposed design mechanisms is presented and discussed through a set of experiments. 相似文献
85.
It has been proposed that the current design of in-vehicle displays may not be appropriate for the older driver. This paper describes an empirical, road-based investigation of the benefits to older and younger drivers of providing landmarks within the instructions presented by an in-vehicle navigation system. Thirty two participants navigated a challenging urban route using either landmarks or distance information to identify the location of forthcoming manoeuvres. A range of driver behaviour measures were collected, including visual glance data, driving errors, driver workload, navigation errors, navigation confidence, and pre and post-trial driver attitudinal responses. Results show that, for older and younger drivers, landmarks reduced the time spent glancing to a visual display, reduced navigation and driving errors, and influenced driver confidence. There were some key differences between the older and younger drivers. The wider implications for the design of in-car interfaces for the older driver are discussed. 相似文献
86.
Soft errors are an important challenge in contemporary microprocessors. Particle hits on the components of a processor are expected to create an increasing number of transient errors with each new microprocessor generation. In this paper we propose simple mechanisms that effectively reduce the vulnerability to soft errors In a processor. Our designs are generally motivated by the fact that many of the produced and consumed values in the processors are narrow and their upper order bits are meaningless. Soft errors canted by any particle strike to these higher order bits can be avoided by simply identifying these narrow values. Alternatively soft errors can be detected or corrected on the narrow values by replicating the vulnerable portion of the value inside the storage space provided for the upper order bits of these operands. We offer a variety of schemes that make use of narrow values and analyze their efficiency in reducing soft error vulnerability of level-1 data cache of the processor 相似文献
87.
88.
Bandyopadhyay B. Avinash Upadhye Osman Ismail 《Automatic Control, IEEE Transactions on》1997,42(8):1127-1130
The paper presents the γ-δ Routh approximation for interval systems. The interval γs and δs are evaluated for the higher order interval systems, and then an rth-order approximant is obtained by retaining the first r, interval δs, and γs. A numerical example illustrates the procedure 相似文献
89.
A detailed experimental programme of work is presented which examines the constrained torsional response of carbon fibre composite beams for the cantilevered configuration with torque applied at the free end. The behaviour of open-section beams and that of single-cell closed-section box beams is reported and discussed and the experimental findings are shown to corroborate simple engineering theoretical approaches. Tests have been carried out on zed and angle-section beams and thus the effects of primary and secondary warping restraint respectively on the torsional response of open-section beams are examined. The behaviour of zed-section beams is governed, in the main, by primary effects and that of angle-section beams is associated solely with secondary effects. The stress distributions along the beams and around the cross-sections are determined from the measured strains during test obtained from surface bonded strain gauges and comparison of these with theory is shown to be in good agreement. The essential differences in response to constrained torsion between open and closed-section beams are detailed in the paper and the importance of experimental tests in the analysis of composite structures is highlighted. 相似文献
90.
By utilising TLC with a developing system of petroleum ether-diethylether-acetic acid (70:30:2 v/v) and allowing the front to travel 18 cm, the best conditions for the fractionation of Bolti tissue lipids were achieved. Four distinct classes—triglycerides, free fatty acids, sterols and phospholipids—were detected. In addition, two other faint classes—hydrocarbons and diglycerides—were identified.Silica gel impregnated with silver nitrate has been employed for the fractionation of the triglycerides into groups. Seven groups were found when 1·5% of ethanol was added to the developing system of chloroform-acetic acid (99·5:0·5 v/v). Raising the ethanol content to 2% resulted in the detection of eight groups. 相似文献