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81.
Abdul Qayoom Mugheri Aneela Tahira Umair Aftab Muhammad Ishaq Abro Arfana Begum Mallah Gulam Zuhra Memon Humaira Khan Mazhar Ali Abbasi Imran Ali Halepoto Saleem Raza Chaudhry Zafar Hussain Ibupoto 《RSC advances》2019,9(59):34136
The design of efficient nonprecious catalysts for the hydrogen evolution reaction (HER) or the oxygen evolution reaction (OER) is a necessary, but very challenging task to uplift the water-based economy. In this study, we developed a facile approach to produce porous carbon from the dehydration of sucrose and use it for the preparation of nanocomposites with cobalt oxide (Co3O4). The nanocomposites were studied by the powder X-ray diffraction and scanning electron microscopy techniques, and they exhibited the cubic phase of cobalt oxide and porous structure of carbon. The nanocomposites showed significant OER activity in alkaline media, and the current densities of 10 and 20 mA cm−2 could be obtained at 1.49 and 1.51 V versus reversible hydrogen electrode (RHE), respectively. The impedance study confirms favorable OER activity on the surface of the prepared nanocomposites. The nanocomposite is cost-effective and can be capitalized in various energy storage technologies.The design of efficient nonprecious catalysts for the hydrogen evolution reaction (HER) or the oxygen evolution reaction (OER) is a necessary, but very challenging task to uplift the water-based economy. 相似文献
82.
Huanrong Fan Al Imran Faizan Raza Irfan ahmed Kamran Amjad Peng Li Yanpeng Zhang 《RSC advances》2019,9(66):38828
In this paper, we study double cascade dressed optical metal oxide semiconductor field-effect transistor (MOSFET) by exploiting enhancement and suppression for mixed-phase (hexagonal + tetragonal) of Eu3+:YPO4 and different phases (hexagonal + tetragonal and pure tetragonal) of Pr3+:YPO4 crystals. We report variation of fine structure energy levels in different doped ions (Eu3+ and Pr3+) in the host YPO crystal. We compared multi-level energy transition from a single dressing laser with single level energy transition from double cascade dressing lasers. Gate delay facilitates multi-energy level dressed transition and is modeled through a Hamiltonian. Based on the results of double cascade dressing, we have realized MOSFET for logic gates (inverter and logic not and gate) with a switching contrast of about 92% using a mixed phase of Pr3+:YPO4.By changing different parameters of single and double lasers, we observed the dressed energy level transition from single to multi-level with a single laser. Each sample responded based on their ions'' structure and phase symmetry in the host YPO crystal. 相似文献
83.
The incorporation of inorganic oxide fillers imparts superior dielectric properties in silicone rubber for high-voltage insulation. However, the dielectric characteristics are influenced by the mechanical stress. The effects of ramped compression on the dielectric properties of neat silicone rubber (NSiR), 15% SiO2 microcomposite (SSMC), 15% alumina trihydrate (ATH) microcomposite (SAMC) and 10% ATH + 2% SiO2 hybrid composite (SMNC) are presented in this study. The dielectric constant and dissipation factor were measured before and after each compression especially in the frequency range of 50 kHz to 2MHz. Before the compression, SSMC expressed the highest dielectric constant of 4.44 followed by SMNC and SAMC. After the compression cycle, SAMC expressed a better dielectric behavior exhibiting dielectric constant of 7.19 and a dissipation factor of 0.01164. Overall, SAMC expressed better dielectric response before and after compression cycle with dielectric constant and dissipation factor in admissible ranges. 相似文献
84.
Purvi Parwani Andrew D. Choi Juan Lopez-Mattei Samreen Raza Tiffany Chen Akhil Narang Erin D. Michos John P. Erwin Mamas A. Mamas Martha Gulati 《Journal of the American College of Cardiology》2019,73(9):1089-1093
Cardiology professionals have used social media platforms such as Twitter to gain exposure to new research, network with experts, share opinions, and engage in scientific debates. The power of social media to communicate openly, with wide-reaching access worldwide, and at a rate faster than ever before makes it a formidable force and voice. However, evolving individual and institutional use has resulted in uncertainty for all parties on how to optimally advance this newer digital frontier. Thus, the purpose of this paper is to: 1) introduce the basics of social media usage (with the focus on Twitter); 2) provide perspective on best social media practices in academic and clinical cardiovascular medicine; and 3) present a vision for social media and the future of cardiovascular medicine. 相似文献
85.
Muhammad Umar Aslam Khan Mohsin Ali Raza Hassan Mehboob Mohammed Rafiq Abdul Kadir Saiful Izwan Abd Razak Saqlain A. Shah Muhammad Zahir Iqbal Rashid Amin 《RSC advances》2021,11(30):18615
Correction for ‘Development and in vitro evaluation of κ-carrageenan based polymeric hybrid nanocomposite scaffolds for bone tissue engineering’ by Muhammad Umar Aslam Khan et al., RSC Adv., 2020, 10, 40529–40542. DOI: 10.1039/D0RA07446B.The authors regret errors in Fig. 9 in the original article. The corrected Fig. 9 is shown below where all three +ive control panels and the 72 h CG-g-Aac-2 panel have been replaced.Open in a separate windowFig. 9Cell morphology of MC3T3-E1 against +ive control and all scaffold samples (CG-g-AAc1, CG-g-AAc2 and CG-g-AAc3) under standard in vitro conditions. The red arrows show thread-like morphology and the yellow arrows exhibits well-grown morphology of the cells.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers. 相似文献
86.
Mohsen Raza Ryan Geleit James Houston Rachel Williams Alex Trompeter 《The British journal of radiology》2021,94(1125)
Objectives:Orthopaedic surgeons have a responsibility to minimise risks of ionising radiation to patients, themselves and staff. This study aims to establish the understanding of radiation practice, legislation and risk by orthopaedic surgeons.Methods:A nationwide online survey of UK-based orthopaedic surgeons was conducted. Participants answered 18 multiple-choice questions assessing level of radiation safety training, basic principles/knowledge of ionising radiation, relevant legislation and operating practice.Results:A total of 406 surgeons completed the survey. 92% reported using intraoperative ionising radiation at least once per week. 38% received no formal training on radiation safety. Knowledge of basic principles of radiation and legislation was limited. There was variable knowledge when labelling an image intensifier machine and choosing its safest orientation. Poor uptake of radiation protection equipment was noted. Only 19% agreed they had adequate training in ionising radiation safety and 27% reported receiving adequate training in equipment emitting ionising radiation in the operating theatre.Conclusion:Many orthopaedic surgeons in the UK do not believe they are adequately trained in radiation safety. There is a deficiency amongst practicing surgeons in basic knowledge, relevant legislation and practicalities of the use of ionising radiation in the operating room. This could potentially put patients and health-care professionals at additional risk. We recommend that a standardised national training programme on the basic principles and safety of ionising radiation is implemented for all practicing orthopaedic surgeons.Advances in knowledge:This paper is the first UK national survey amongst orthopaedic surgeons and is one of the largest reported internationally. 相似文献
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88.
Raya Saab MD Anas Obeid MD Fatiha Gachi MD Houda Boudiaf MD Lilit Sargsyan MD Khulood Al-Saad MD Tamar Javakhadze MD Azim Mehrvar MD Sawsan Sati Abbas MD Yasir Saadoon Abed Al-Agele MD Salma Al-Haddad MD Mouroge Hashim Al Ani MD Suleiman Al-Sweedan MD Amani Al Kofide MD Wasil Jastaniah MD Nisreen Khalifa MD Elie Bechara MD Malek Baassiri MD Peter Noun MD Jamila El-Houdzi MD Mohammed Khattab MD Krishna Sagar Sharma MD Yasser Wali MD Naureen Mushtaq MD Aliya Batool MD Mahwish Faizan MD Muhammad Rafie Raza MD Mohammad Najajreh MD Mohammed Awad Mohammed Abdallah MD Ghada Sousan MD Khaled M. Ghanem MD Ulker Kocak MD Tezer Kutluk MD Hacı Ahmet Demir MD Hamoud Hodeish MD Samar Muwakkit MD Asim Belgaumi MD Abdul-Hakim Al-Rawas MD Sima Jeha MD 《Cancer》2020,126(18):4235-4245
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