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51.
Rajender Prasad Tiwari Syed Zimad Husain Hashmi Raghav Sharma Saif Ahmad Khan Balaji Birajdar 《Journal of the American Ceramic Society》2019,102(8):4659-4669
Residual NiO phase is generally detected in 0.9(KNbO3)–0.1(BaNi1/2Nb1/2O3-δ) (KBNNO) synthesized using NiO as a nickel precursor by solid-state reaction. In this work, NiO phase is found to exist in the form of the residual NiO particles with a size of 100-200 nm using energy dispersive X-ray elemental mapping. These NiO residual particles are eliminated by using nickel acetate as a nickel precursor and a 100% perovskite phase KBNNO is successfully synthesized at as low as 600°C temperature. Furthermore, using the two-step sintering technique, 100% relative density is achieved in this material. The nickel acetate–based KBNNO shows a robust ferromagnetism with the saturation magnetization of 11.42 memu/g and the remanent magnetization of 3.89 memu/g which is 38 times higher than that of previously reported value in NiO-based KBNNO. Thus, a highly pure and fully dense KBNNO ceramic with superior magnetic properties is obtained using nickel acetate and by the two-step sintering method. This is a key step forward in the processing of KBNNO and is likely to have a significant impact on other physical properties of this newly invented and promising photovoltaic perovskite material. 相似文献
52.
Syed Hashim Raza Bukhari Sajid Siraj Mubashir Husain Rehmani 《Wireless Networks》2018,24(5):1543-1559
In this paper, we propose a simulation model for cognitive radio sensor networks (CRSNs) which is an attempt to combine the useful properties of wireless sensor networks and cognitive radio networks. The existing simulation models for cognitive radios cannot be extended for this purpose as they do not consider the strict energy constraint in wireless sensor networks. Our proposed model considers the limited energy available for wireless sensor nodes that constrain the spectrum sensing process—an unavoidable operation in cognitive radios. Our model has been thoroughly tested by performing experiments in different scenarios of CRSNs. The results generated by the model have been found accurate which can be considered for realization of CRSNs. 相似文献
53.
KI Arnautovi? O al-Mefty TG Pait AF Krisht MM Husain 《Canadian Metallurgical Quarterly》1997,86(2):252-262
The authors studied the microsurgical anatomy of the suboccipital region, concentrating on the third segment (V3) of the vertebral artery (VA), which extends from the transverse foramen of the axis to the dural penetration of the VA, paying particular attention to its loops, branches, supporting fibrous rings, adjacent nerves, and surrounding venous structures. Ten cadaver heads (20 sides) were fixed in formalin, their blood vessels were perfused with colored silicone rubber, and they were dissected under magnification. The authors subdivided the V3 into two parts, the horizontal (V3h) and the vertical (V3v), and studied the anatomical structures topographically, from the superficial to the deep tissues. In two additional specimens, serial histological sections were acquired through the V3 and its encircling elements to elucidate their cross-sectional anatomy. Measurements of surgically and clinically important features were obtained with the aid of an operating microscope. This study reveals an astonishing anatomical resemblance between the suboccipital complex and the cavernous sinus, as follows: venous cushioning; anatomical properties of the V3 and those of the petrous-cavernous internal carotid artery (ICA), namely their loops, branches, supporting fibrous rings, and periarterial autonomic neural plexus; adjacent nerves; and skull base locations. Likewise, a review of the literature showed a related embryological development and functional and pathological features, as well as similar transitional patterns in the arterial walls of the V3 and the petrous-cavernous ICA. Hence, due to its similarity to the cavernous sinus, this suboccipital complex is here named the "suboccipital cavernous sinus." Its role in physiological and pathological conditions as they pertain to various clinical and surgical implications is also discussed. 相似文献
54.
Munda Parikshit Husain Md. M. Soni M. K. Kumar Pankaj Rajinikanth V. 《Journal of Failure Analysis and Prevention》2019,19(1):161-176
Journal of Failure Analysis and Prevention - A dragline is the largest mobile equipment on earth, and it is called the “kingpin” of any mine site. In this present investigation, a case... 相似文献
55.
Ngo Quang Trung Nguyen Van Thanh Nguyen Viet Tinh Syed Tam Husain 《计算机、材料和连续体(英文)》2022,72(3):4557-4570
The finance supply chain has always been a different supply chain compared to product supply chain being a service supply chain. Open Banking (OB) is one of the most important milestones since the beginning of financial technology innovation and service supply chain. As these are activities provided by traditional banks, non-bank financial institutions also provide financial service with access to consumer banking, transactional and other financial data to develop financial applications and services tailored to their customers. The development of financial technology, “Open banking”, promotes financial services to begin this transformation. However, evaluating and selecting open banking business partners from multiple perspectives for banks are underexplored. Thus, the authors in this research proposed a hybrid multi-criteria decision-making model which includes a Spherical Fuzzy Analytical Hierarchy Process (SF-AHP) model and a Multi-Attributive Ideal-Real Comparative Analysis (MAIRCA) model with supports from seasoned domain experts. The contribution of this research is a proposition of a fuzzy decision model for evaluating and selecting open banking business partners. The model successfully determined a suitable open bank provider in order to assist decision makers decide objectively. 相似文献
56.
Characterization of piezoelectric ceramics using the burst/transient method with resonance and antiresonance analysis
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Husain Shekhani Timo Scholehwar Eberhard Hennig Kenji Uchino 《Journal of the American Ceramic Society》2017,100(3):998-1010
In this paper, a comprehensive methodology for characterizing the high power resonance behavior of bulk piezoelectric ceramics using the burst method is described. In the burst method, the sample is electrically driven at its resonance frequency, and then either a short circuit or an open circuit condition is imposed, after which the vibration decays at the resonance or antiresonance frequency, respectively. This decay can be used to measure the quality factor in either of these conditions. The resulting current in the short circuit vibration condition is related to the vibration velocity through the “force factor.” The generated voltage in the open circuit vibration condition corresponds to the displacement by the “voltage factor.” The force factor and the voltage factor are related to material properties and physical dimensions of the sample. Using this method, the high power behavior of the permittivity, compliance, effective piezoelectric charge constant, electromechanical coupling factor, and material losses can be determined directly by measuring the resonance (short circuit) and antiresonance (open circuit) frequencies, their corresponding quality factors, the force factor A, and the voltage factor B. The experimental procedure to apply this method is described and demonstrated on commercially available hard and semi‐hard PZT materials of geometry. 相似文献
57.
Network coding is a data processing technique in which the flow of digital data is optimized in a network by transmitting a composite of two or more messages to make the network more robust. Network coding has been used in traditional and emerging wireless networks to overcome the communications issues of these networks. It also plays an important role in the area of vehicular ad-hoc networks (VANETs) to meet the challenges like high mobility, rapidly changing topology, and intermittent connectivity. VANETs consist of network of vehicles in which they communicate with each other to ensure road safety, free flow of traffic, and ease of journey for the passengers. It is now considered to be the most valuable concept for improving efficiency and safety of future transportation. However, this field has a lot of challenges to deal with. This paper presents a comprehensive survey of network coding schemes in VANETs. We have classified different applications like content distribution, multimedia streaming, cooperative downloading, data dissemination, and summarized other key areas of VANETs in which network coding schemes are implemented. This research work will provide a clear understanding to the readers about how network coding is implemented in these schemes in VANETs to improve performance, reduce delay, and make the network more efficient. 相似文献
58.
Phylogenetic Studies,Gene Cluster Analysis,and Enzymatic Reaction Support Anthrahydroquinone Reduction as the Physiological Function of Fungal 17β‐Hydroxysteroid Dehydrogenase
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Leon Fürtges David Conradt Dr. Michael A. Schätzle Shailesh Kumar Singh Dr. Nada Kraševec Prof. Dr. Tea Lanišnik Rižner Prof. Dr. Michael Müller Dr. Syed Masood Husain 《Chembiochem : a European journal of chemical biology》2017,18(1):77-80
17β‐Hydroxysteroid dehydrogenase (17β‐HSDcl) from the filamentous fungus Curvularia lunata (teleomorph Cochliobolus lunatus) catalyzes NADP(H)‐dependent oxidoreductions of androgens and estrogens. Despite detailed biochemical and structural characterization of 17β‐HSDcl, its physiological function remains unknown. On the basis of amino acid sequence alignment, phylogenetic studies, and the recent identification of the physiological substrates of the homologous MdpC from Aspergillus nidulans and AflM from Aspergillus parasiticus, we propose an anthrahydroquinone as the physiological substrate of 17β‐HSDcl. This is also supported by our analysis of a secondary metabolite biosynthetic gene cluster in C. lunata m118, containing 17β‐HSDcl and ten other genes, including a polyketide synthase probably involved in emodin formation. Chemoenzymatic reduction of emodin by 17β‐HSDcl in the presence of sodium dithionite verified this hypothesis. On the basis of these results, the involvement of a 17β‐HSDcl in the biosynthesis of other anthrahydroquinone‐derived natural products is proposed; hence, 17β‐HSDcl should be more appropriately referred to as a polyhydroxyanthracene reductase (PHAR). 相似文献
59.
The Kingdom of Saudi Arabia has initiated a program to install air quality network stations throughout the country in order to measure concentration of the ambient air pollutants. The site selection of these stations is an important objective to be accomplished and must be done based on scientific and rational work. To accomplish this objective, a modified version of atmospheric transport and dispersion model, known as air resources laboratories - atmospheric transport and dispersion (ARLATAD) model, is used to evaluate long range transport and diffusion of air pollutants from major pollution causing sources such as refineries, open-air burning of associated gases of oil fields and major industries.Hourly meteorological data for a period of three years (from 1977 to 1979) on wind speed, wind direction, pressure, and temperature from 20 synoptic stations in Saudi Arabia is processed and used as model input. In addition to these, meteorological data from three upper air stations is also processed in order to determine base and top of critical inversion heights.Various pollution causing sources are identified within the study area. Air trajectories are drawn with sources as the origins of the trajectories and the dispersion characteristics is studied with distance and time. Based on long term meteorological records, the adversely affected zones are statistically identified for potential station sites. 相似文献
60.
K. P. Singh V. P. S. Awana S. Balamurugan M. Shahabuddin H. K. Singh M. Husain H. Kishan E. R. Bauminger I. Felner 《Journal of Superconductivity and Novel Magnetism》2008,21(1):39-44
Nano particle of Fe3O4 (nFe3O4) up to 6 at% were doped in the superconducting MgB2 samples. Despite the strong ferromagnetic nature of Fe3O4, both the ac susceptibility and the resistivity measurements show that up to 4 at% of Fe3O4, T
c
=38 K is not changed, whereas for 6% T
c
decreases by 6 K. This indicates that a low concentration of Fe does not substitute either the Mg or B sites and probably
occupies the intergrain spaces. For 0.5% doped Fe3O4, an increase in J
c
with respect to the pure MgB2 samples is observed in the lower field and temperature regions (H<2 T and 20 K) indicating an enhanced flux pinning and the magnetic activation, i.e., the interaction between the magnetic
dipole of Fe ion and the vortices is weak in comparison to the effective pinning potential. Whereas, at H>2 T, J
c
of the doped samples is always less than that of MgB2, and the activation is dominant in comparison with the effective pinning potential provided by the doping. Flux jumps are
observed in lower T and H regions for the samples doped up to 1% nFe3O4 only. Magnetization plots of higher Fe content samples exhibited clear paramagnetic background. Mossbauer measurements for
the higher (4, 6 at%) nFe3O4 doped MgB2 samples show that at RT, the hyperfine field for both samples is ∼100 kOe and ∼120 kOe at 90 K. This means that the nFe3O4 particles decompose and form possibly an intermetallic Fe-B phase in the matrix. 相似文献