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31.
Perpetua Wanjiru Muchiri M. Agouri Sahar Abdeen Mohamed A. Abbassi S. Taj B. Manaut Ashim Dutta Junaid Khan T. Mundad Youssef Bakkour Murefah mana Al-Anazy 《International journal of quantum chemistry》2024,124(7):e27368
This research work investigates the structural, electronic, optical, and thermoelectric characteristics of VFeZ (Z = N and P) half-Heusler compounds. The study employs the full-potential linearized augmented plane wave (FP-LAPW) method integrated into the WIEN2K algorithm, serving as the underpinning framework for density functional theory (DFT) analysis. In the study, we use the PBE generalized gradient approximation (PBE-GGA) to identify numerous parameters associated with structural and elastic properties. Lattice parameter results are in agreement with previous outcomes. Moreover, computed elastic parameters satisfy the criterion for stability. In the cubic structure VFeZ (Z = N and P) is ductile, to enhance the computations of electronic characteristics, Tran and Blaha's modified Becke-Johnson potential (TB-mBJ) is used. Our simulations demonstrate that the materials exhibit semiconductor behavior, with a direct band gap for VFeZ (Z = N and P). Strong UV absorption is found via optical experiments suggest compounds are suitable for optical application. Furthermore, study of the thermoelectric properties suggests its application in the thermoelectric generators. 相似文献
32.
Mohammad Hossein Keshavarz Sahar Belyani Seyyed Mohammad Reza Darbani Masoud Kavosh Tehrani 《无机化学与普通化学杂志》2019,645(16):1057-1061
Laser Induced Breakdown Spectroscopy (LIBS) method is introduced as a novel approach in this work to study catalyst deactivation of V2O5/γ‐‐Al2O3 for gas‐phase dehydration of glycerol and producing acrolein. The LIBS results of V2O5/γ‐Al2O3 samples are compared with those data that are obtained by Inductively Coupled Plasma Optical Emission Spectrometry (ICP‐OES). Experimental data of LIBS data specify that line intensities of vanadium are decreased by deactivation of V2O5/γ‐Al2O3 catalyst. A comparison between the results of LIBS test as well as ICP‐OES analysis shows that the amount of vanadium is decreased in the catalyst. Moreover, coke formation changes the surface of the catalyst. The results of deactivation of V2O5/γ‐Al2O3 are also compared with Pd/C catalyst deactivation. 相似文献
33.
Er3+-doped tellurite glasses of the (80 ? x)TeO2–20ZnO–(x)Er2O3 system (0.5 mol% ? x ? 2.5 mol%) have successfully been made by melt-quenching technique and their structure has been investigated by means of DTA and Raman spectroscopy. The DTA results show the thermal parameters; such as the glass transition temperature (Tg) and crystallization temperature (Tc) were determined. It is found that this system provides a stable and wide glass formation range in which the glass stability around 99–140 °C may be obtained. The Raman spectroscopy used the structural studies in the glass system. Two Raman shift peaks were observed around 640–670 cm?1 and 720–740 cm?1, which correspond to the stretching vibration mode of TeO4 tbp and TeO3 tp, respectively. It is found that the spectral shift in Raman spectra is depending on the Er2O3 content. This evolution is an indication of the changes in the basic unit of the glass structure. 相似文献
34.
Hernandez Gustavo Castillo Yasseri Mohammad Ayachi Sahar de Boor Johannes Müller Eckhard 《Semiconductors》2019,53(13):1831-1837
Semiconductors - Thermoelectric material development typically aims at maximizing produced electrical power and efficiency of energy conversion, even though sometimes, this means adding expensive... 相似文献
35.
36.
Cerium-doped zirconium oxide (Ce/ZrO2) was introduced as a highly efficient electrocatalyst for electrooxidation of salicylic acid (SA). The electrocatalyst material was synthesized via co-precipitation of cerium and zirconium ions, and then the resulting solid was heat-treated at high temperature to create crystallized cerium-doped zirconium oxide nanoparticles. The obtained material was characterized by scanning electron microscopy and X-ray diffraction methods. The Ce/ZrO2-modified carbon paste electrode (Ce/ZrO2-CPE) exhibited a distinct oxidative peak for SA, whereas no signal was observed for SA at unmodified carbon paste electrode at the same experimental conditions. Cyclic voltammetry and electrochemical impedance spectroscopy were applied to investigate the electrocatalytic performance of the electrode and SA electrooxidation mechanism. Square wave voltammetry was used to capture the analytical signal of SA. The electrode composition was optimized to increase the SA signal. Using the optimized electrode, it became possible to determine SA in the concentration range of 5.0–1000.0 μM with detection limit of 1.1 μM (3Sb/m). The electrode showed very high sensitivity of 1013.5 μA mM?1 cm?2 which is remarkably better than the previously reported SA sensors. The proposed method was successfully applied for the determination of SA in human serum, milk, and pharmaceutical samples. 相似文献
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38.
Ghobadi Nader Hafezi Fatemeh Naderi Sirvan Amiri Fatemeh Luna Carlos Arman Ali Shakoury Reza Ţălu Ştefan Rezaee Sahar Habibi Maryam Mardani Mohsen 《Semiconductors》2019,53(13):1751-1758
Semiconductors - The purpose of this research is to explore the properties of CoSe nanostructured thin films on glass substrates prepared by a chemical solution deposition method. Special attention... 相似文献
39.
Latterly, reduction of power loss in distribution system is the objective of many researches due to its impact on total costs and voltage profiles. It can be handled by optimal restructure of radial distribution system (RDS). This article introduces an innovative approach to restructure of RDS by electing the optimal switches combination subject to the system operating constraints, which is improved whale optimization approach (IWOA). The suggested approach combines exploitation of WOA with exploration of differential evolution (DE), and thus, it supplies a promising candidate solution. The suggested approach is tested on IEEE 33 and 69 bus RDS. The superiority of the suggested approach compared with other well‐known approaches is verified through simulation results by observation of total losses, cost, and saving. Also, the impact of alterable loading is investigated to prove the effectiveness of the suggested IWOA. 相似文献
40.
Sahar Chagharvand Mohamad Rijal Hamid Muhammad Ramlee Kamarudin James R. Kelly 《Telecommunication Systems》2017,65(1):79-85
This paper presents a Vivaldi antenna. The antenna incorporates a slot-line feed, and is designed to operate in a wideband mode, along with four narrowband modes. The wideband mode extends from 1 to 3 GHz. A series of PIN diode switches is employed to reconfigure between the five different operating modes. Wideband-to-multiband reconfigurations are achieved by adjusting the antenna loading internally, and also by the incorporation of band-stop filters. To obtain the wideband mode, wideband matches load is used. On the other hand, to obtain the narrowband modes, two rectangular slits with narrowband matches load are used. The proposed Vivaldi antenna provides wideband operation. It is also supports operation within the LTE, GSM (L-band), GPS, and WiMAX bands. 相似文献