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1.
Kuznetsov I. V. Budin O. N. Shchepin A. S. Kalenova M. Yu. Mel’nikova I. M. Saprykin R. V. Al’zhev N. I. 《Inorganic Materials》2022,58(6):651-660
Inorganic Materials - We have studied the effect of annealing on the chemical and physical properties of mineral-like host matrices for immobilization of the rare-earth–actinide fraction from... 相似文献
2.
A NEW OIL SEEPAGE IN THE OMAN MOUNTAINS AND ITS GEOLOGICAL,GEOCHEMICAL AND PETROLEUM SYSTEMS CONTEXT
Mohammed Al Kindi Mohammed Al-Ghammari Alan Heward Paul Taylor George Siavalas 《Journal of Petroleum Geology》2022,45(1):5-28
A minor natural oil seepage is described from an unlikely setting in the Oman Mountains. The host rocks are fractured pelagic limestones of the lower member of the Triassic – Lower Jurassic Matbat Formation of the Hamrat Duru Group in the lower part of the allochthonous Hawasina Complex. This paper summarises Oman's established oil families and documents previously recorded oil seepages as context for describing the new seepage, its geochemistry, and possible source rock. The seep oil is different to those known from Oman's oil fields and probably derived from a poor quality, Mesozoic clastic source rock containing a mix of terrigenous and marine organic matter. The most likely source appears to be the Toarcian turbiditic upper member of the Matbat Formation, equivalent to the clastic Mafraq Formation of the Arabian Platform. The occurrence of source rocks in the allochthonous sediments of the NeoTethyan Hawasina Basin has been suspected previously, though their commercial significance remains to be established. 相似文献
3.
Wireless Personal Communications - Current mobile communications technology relies heavily on efficient design of antennas, where the operational characteristics of the wireless communication... 相似文献
4.
Abdallah M. Altass H. M. El-Sayed R. Al Gorair Arej S. Jahdaly B. A. AL Sobhi M. 《Protection of Metals and Physical Chemistry of Surfaces》2021,57(4):811-819
Protection of Metals and Physical Chemistry of Surfaces - Three nonionic surfactants molecules (NS) derived from a fused pyridine characterized by IR and 1HNMR spectra were synthesized and examined... 相似文献
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Nader Tehrani Dan Gallagher Monica Ponce de Leon Harry Lowd Richard Lee Lisa Huang Remon Alberts Janghwan Cheon Jumanah Jamal Aishah Al Sager 《世界建筑导报》2018,(2)
正Banq餐厅位是一家新型餐厅,位于便士储蓄银行(Penny Savings Bank)旧大楼以前用来经营银行业务的大厅内。餐厅分成两个部分,前面区域面向华盛顿大街,设计成酒吧,后面的大厅则作为用餐区。然而,这个空间在z轴上以天花板和地面之间的另一个分区为中心进行设计。如果由于餐厅空间活动的多变性而需要保持灵活性——包括两个座位、四个座位和六个座位,以及与聚会和其他活动有关的座位 相似文献
8.
Lianfeng Zhao Kwangdong Roh Sara Kacmoli Khaled Al Kurdi Samik Jhulki Stephen Barlow Seth R. Marder Claire Gmachl Barry P. Rand 《Advanced materials (Deerfield Beach, Fla.)》2020,32(25):2000752
The performance of lead-halide perovskite light-emitting diodes (LEDs) has increased rapidly in recent years. However, most reports feature devices operated at relatively small current densities (<500 mA cm−2) with moderate radiance (<400 W sr−1 m−2). Here, Joule heating and inefficient thermal dissipation are shown to be major obstacles toward high radiance and long lifetime. Several thermal management strategies are proposed in this work, such as doping charge-transport layers, optimizing device geometry, and attaching heat spreaders and sinks. Combining these strategies, high-performance perovskite LEDs are demonstrated with maximum radiance of 2555 W sr−1 m−2, peak external quantum efficiency (EQE) of 17%, considerably reduced EQE roll-off (EQE > 10% to current densities as high as 2000 mA cm−2), and tenfold increase in operational lifetime (when driven at 100 mA cm−2). Furthermore, with proper thermal management, a maximum current density of 2.5 kA cm−2 and an EQE of ≈1% at 1 kA cm−2 are shown using electrical pulses, which represents an important milestone toward electrically driven perovskite lasers. 相似文献
9.
Abbas Khan. Dong-Qing Wei Kafila Kousar Jehad Abubaker Sajjad Ahmad Javaid Ali Fahd Al-Mulla Syed Shujait Ali N. Nizam-Uddin Abrar Mohammad Sayaf Anwar Mohammad 《Chembiochem : a European journal of chemical biology》2021,22(16):2641-2649
The evolution of new SARS-CoV-2 variants around the globe has made the COVID-19 pandemic more worrisome, further pressuring the health care system and immunity. Novel variations that are unique to the receptor-binding motif (RBM) of the receptor-binding domain (RBD) spike glycoprotein, i. e. L452R-E484Q, may play a different role in the B.1.617 (also known as G/452R.V3) variant's pathogenicity and better survival compared to the wild type. Therefore, a thorough analysis is needed to understand the impact of these mutations on binding with host receptor (RBD) and to guide new therapeutics development. In this study, we used structural and biomolecular simulation techniques to explore the impact of specific mutations (L452R-E484Q) in the B.1.617 variant on the binding of RBD to the host receptor ACE2. Our analysis revealed that the B.1.617 variant possesses different dynamic behaviours by altering dynamic-stability, residual flexibility and structural compactness. Moreover, the new variant had altered the bonding network and structural-dynamics properties significantly. MM/GBSA technique was used, which further established the binding differences between the wild type and B.1.617 variant. In conclusion, this study provides a strong impetus to develop novel drugs against the new SARS-CoV-2 variants. 相似文献
10.
Hameed Al‐Attar Aula A Alwattar Athir Haddad Bassil A Abdullah Peter Quayle Stephen G Yeates 《Polymer International》2021,70(1):51-58
In this work we demonstrate, for the first time, the use of polylactic acid (PLA) as a biodegradable host matrix for the construction of the active emissive layer of organic light‐emitting diode (OLED) devices for potential use in bioelectronics. In this preliminary study, we report a robust synthesis of two fluorescent PLA derivatives, pyrene‐PLA ( AH10 ) and perylene‐PLA ( AH11 ). These materials were prepared by the ring opening polymerisation of l ‐lactide with hydroxyalkyl‐pyrene and hydroxyalkyl‐perylene derivatives using 1,8‐diazabicyclo[5.4.0]undec‐7‐ene as catalyst. OLEDs were fabricated from these materials using a simple device architecture involving a solution‐processed single‐emitting layer in the configuration ITO/PEDOT:PSS/PVK:OXD‐7 (35%): AH10 or AH11 (20%)/TPBi/LiF/Al (ITO, indium tin oxide; PEDOT:PSS, poly(3,4‐ethylenedioxythiophene) doped with poly(styrenesulfonic acid); PVK, poly(vinylcarbazole); OXD‐7, (1,3‐phenylene)‐bis‐[5‐(4‐tert‐butylphenyl)‐1,3,4‐oxadiazole]; TPBi, 2,2′,2″‐(1,3,5‐benzenetriyl)tris(1‐phenyl‐1H‐benzimidazole)). The turn‐on voltage for the perylene OLED at 10 cd m–2 was around 6 V with a maximum brightness of 1200 cd m–2 at 13 V. The corresponding external quantum efficiency and device current efficiency were 1.5% and 2.8 cd A–1 respectively. In summary, this study provides proof of principle that OLEDs can be constructed from PLA, a readily available and renewable bio‐source. © 2020 The Authors. Polymer International published by John Wiley & Sons Ltd on behalf of Society of Industrial Chemistry. 相似文献