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371.
Sajid Muhammad Usman Ali Hafiz Muhammad Sufyan Abu Rashid Danial Zahid Saad Ullah Rehman Wajih Ur 《Journal of Thermal Analysis and Calorimetry》2019,137(4):1279-1294
Journal of Thermal Analysis and Calorimetry - The present study comprises experimental investigation on heat transfer and hydrodynamic characteristics of TiO2 nanofluid as coolant in wavy channel... 相似文献
372.
Iftikhar Ahmad Hassan Adnan Anjum Muneeb Ullah Malik Sohail Ali Tashfeen 《Acoustical Physics》2019,65(5):471-477
Acoustical Physics - In this article, an acoustic energy harvester (AEH) is conceptualized, designed, fabricated and tested. The developed AEH (DAEH) consists of two Helmholtz cavities (HCs) and a... 相似文献
373.
Dr. Ziqi Hu Aman Ullah Dr. Helena Prima-Garcia Sang-Hyun Chin Dr. Yuanyuan Wang Dr. Juan Aragó Prof. Zujin Shi Dr. Alejandro Gaita-Ariño Prof. Eugenio Coronado 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(52):13242-13248
To design molecular spin qubits with enhanced quantum coherence, a control of the coupling between the local vibrations and the spin states is crucial, which could be realized in principle by engineering molecular structures via coordination chemistry. To this end, understanding the underlying structural factors that govern the spin relaxation is a central topic. Here, we report the investigation of the spin dynamics in a series of chemically designed europium(II)-based endohedral metallofullerenes (EMFs). By introducing a unique structural difference, i. e. metal-cage binding site, while keeping other molecular parameters constant between different complexes, these manifest the key role of the three low-energy metal-displacing vibrations in mediating the spin-lattice relaxation times (T1). The temperature dependence of T1 can thus be normalized by the frequencies of these low energy vibrations to show an unprecedentedly universal behavior for EMFs in frozen CS2 solution. Our theoretical analysis indicates that this structural difference determines not only the vibrational rigidity but also spin-vibration coupling in these EMF-based qubit candidates. 相似文献
374.
Ullah H. Khan F. Taha M. Rahim F. Sarfraz M. Aziz A. Ullah S. Khan M. U. Ullah M. 《Russian Journal of Organic Chemistry》2021,57(12):1993-2001
Russian Journal of Organic Chemistry - A series of sixteen oxadiazole derivatives containing a thiazole ring were synthesized, characterized by different spectroscopic techniques (1H and 13C NMR,... 相似文献
375.
Nasru Minallah Khadem Ullah Jaroslav Frnda Korhan Cengiz Muhammad Awais Javed 《Entropy (Basel, Switzerland)》2021,23(2)
The reliable transmission of multimedia information that is coded through highly compression efficient encoders is a challenging task. This article presents the iterative convergence performance of IrRegular Convolutional Codes (IRCCs) with the aid of the multidimensional Sphere Packing (SP) modulation assisted Differential Space Time Spreading Codes (IRCC-SP-DSTS) scheme for the transmission of H.264/Advanced Video Coding (AVC) compressed video coded stream. In this article, three different regular and irregular error protection schemes are presented. In the presented Regular Error Protection (REP) scheme, all of the partitions of the video sequence are regular error protected with a rate of 3/4 IRCC. In Irregular Error Protection scheme-1 (IREP-1) the H.264/AVC partitions are prioritized as A, B & C, respectively. Whereas, in Irregular Error Protection scheme-2 (IREP-2), the H.264/AVC partitions are prioritized as B, A, and C, respectively. The performance of the iterative paradigm of an inner IRCC and outer Rate-1 Precoder is analyzed by the EXtrinsic Information Transfer (EXIT) Chart and the Quality of Experience (QoE) performance of the proposed mechanism is evaluated using the Bit Error Rate (BER) metric and Peak Signal to Noise Ratio (PSNR)-based objective quality metric. More specifically, it is concluded that the proposed IREP-2 scheme exhibits a gain of 1 dB with reference to the IREP-1 and gain of 0.6 dB with reference to the REP scheme over the PSNR degradation of 1 dB. 相似文献
376.
Babazadeh Houman Shah Zahir Ullah Ikram Kumam Poom Shafee Ahmad 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1129-1137
Journal of Thermal Analysis and Calorimetry - We investigate the hybrid nanofluid convection transportation within a permeable medium in appearance of an externally applied magnetic force by... 相似文献
377.
Khan Sami Ullah Tlili Iskander Waqas Hassan Imran Muhammad 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1175-1186
Journal of Thermal Analysis and Calorimetry - The aim of the current contribution is to exploit the effects of nonlinear thermal radiation and activation energy on the flow of modified second-grade... 相似文献
378.
Fatima Zahra Jawhari Abdelfattah El Moussaoui Mohammed Bourhia Hamada Imtara Hamza Mechchate Imane Es-Safi Riaz Ullah Essam Ezzeldin Gamal A. Mostafa Andriy Grafov Samir Ibenmoussa Dalila Bousta Amina Bari 《Molecules (Basel, Switzerland)》2020,25(22)
Background: Anacyclus pyrethrum (A. pyrethrum) is a wild species belonging to the family Asteraceae, which is used in traditional medicines. Aim of the study: This work was undertaken to study the chemical composition, analgesic, anti-inflammatory, and wound healing properties of hydroalcoholic extracts of different parts (roots, seeds, leaves, and capitula) of A. pyrethrum. Material and Methods: The phytochemical analysis of the studied extracts was conducted by GC-MS. The analgesic activity was evaluated in mice using acetic acid and formaldehyde methods. The anti-inflammatory activity was tested using the inhibitory method of edema induced in rats. The healing activity of the hydroethanolic extracts was explored by excision and incision wound healing models in rats. Results: The phytochemical analysis of the studied plant extracts affirmed the presence of interesting compounds, including some newly detected elements, such as sarcosine, N-(trifluoroacetyl)-butyl ester, levulinic acid, malonic acid, palmitic acid, morphinan-6-One, 4,5.alpha.-epoxy-3-hydroxy-17-methyl, 2,4-undecadiene-8,10-diyne-N-tyramide, and isovaleric acid. The extracts of different parts (roots, seeds, leaves, and capitula) exhibited promising anti-inflammatory, analgesic, and wound healing effects, with percentages of inhibition up to 98%, 94%, and 100%, respectively. Conclusion: This study might contribute towards the well-being of society as it provides evidence on the potential analgesic, anti-inflammatory, and wound healing properties of A. pyrethrum. 相似文献
379.
Muhammad Ashraf Syed Shaheen Shah Dr. Ibrahim Khan Dr. Md. Abdul Aziz Prof. Nisar Ullah Dr. Mujeeb Khan Dr. Syed Farooq Adil Zainab Liaqat Dr. Muhammad Usman Prof. Wolfgang Tremel Dr. Muhammad Nawaz Tahir 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(23):6973-6984
Tungsten oxide/graphene hybrid materials are attractive semiconductors for energy-related applications. Herein, we report an asymmetric supercapacitor (ASC, HRG//m-WO3 ASC), fabricated from monoclinic tungsten oxide (m-WO3) nanoplates as a negative electrode and highly reduced graphene oxide (HRG) as a positive electrode material. The supercapacitor performance of the prepared electrodes was evaluated in an aqueous electrolyte (1 m H2SO4) using three- and two-electrode systems. The HRG//m-WO3 ASC exhibits a maximum specific capacitance of 389 F g−1 at a current density of 0.5 A g−1, with an associated high energy density of 93 Wh kg−1 at a power density of 500 W kg−1 in a wide 1.6 V operating potential window. In addition, the HRG//m-WO3 ASC displays long-term cycling stability, maintaining 92 % of the original specific capacitance after 5000 galvanostatic charge–discharge cycles. The m-WO3 nanoplates were prepared hydrothermally while HRG was synthesized by a modified Hummers method. 相似文献
380.
Chayanika Kashyap Indrani Baruah Shahnaz S. Rohman Sabnam S. Ullah Amlan J. Kalita Gargi Borgohain Ankur K. Guha 《International journal of quantum chemistry》2020,120(23):e26386
An extended computational approach has been utilized to explore the reactions of acids with carbonyl oxide, also known as Criegee intermediate (CI). The reactions were explored inside a water cluster containing 50 water molecules. All possibilities of product formation were considered. Among the considered acids, the rate of 1,4-insertion follows the order HCOO < HCl < HNO3. The most stable products of the reactions between the considered acids and CI have been identified. 相似文献