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91.
92.
Muhammad Rehan Asghar Bhatti Muhammad Ahsan Mir Muhammad Umar Tom Cassidy 《纺织学会志》2019,110(6):932-940
A study of significant factors and their interaction during vortex yarn spinning has been carried out to achieve desired mechanical properties of the polyethylene terephthalate/cotton blended yarns which can offer process and performance advantages. The key significant factors, i.e. feed ratio, air pressure and spindle size were varied in a mixed-level factorial design. The mechanical properties (count lea strength product, tenacity and elongation at break) were studied and feed ratio was found to significantly affect the tenacity and elongation at break of spun yarns. A significant effect of these parameters was observed on the diameter and hairiness of the Muratec vortex spun yarn. 相似文献
93.
Rukia Fatima Muhammad Farooq Warsi Muhammad Ilyas Sarwar Imran Shakir Philips O. Agboola Mohamed F. Aly Aboud Sonia Zulfiqar 《Ceramics International》2021,47(6):7642-7652
A new AgO.CuO.WO3/rGO nanocomposite was designed for the investigation of the degradation ability of the hybrid material under visible light irradiation. The AgO, CuO, WO3 NPs, and AgO.CuO.WO3 hetero-metallic oxides were fabricated via the chemical co-precipitation method. The crystallite sizes and phase analyses were investigated by recording X-ray diffraction patterns. The crystallite sizes of three metal oxides in the AgO.CuO.WO3 hetero metal oxide were 16.7, 15.9, and 16.9 nm, respectively. The FESEM images at various magnifications were probed to study the morphology of synthesized materials. The micrographs of hetero-metallic oxides AgO.CuO.WO3 exposed that three metal oxides merged like small particles and gives a large bulbous appearance. EDX analyses confirmed the formation of required materials with high purity. FTIR data was in agreement with the literature which facilitated to ensure the purity of synthesized samples. The optical bandgap energy was calculated via the Tauc plot indicating that the blend of three metal oxides generated a new energy level in the electronic structure is suitable for photocatalysis in the presence of visible light. The bandgap energy of hetero metallic oxides was 1.25 eV which is less than individual metal oxides signifying the tuning of the bandgap. The incorporation of rGO in AgO.CuO.WO3 hetero-metallic oxides gives a new photocatalyst for optimum photodegradation of methylene blue in minimum time. The percentage degradation via AgO.CuO.WO3 was 87.20% in 70 min while the percentage degradation via AgO.CuO.WO3/rGO recorded by photocatalytic experiment was 95% in 40 min. The photocatalysis data revealed that AgO.CuO.WO3 hetero-metallic oxides-rGO nanocomposite ensured a strong potential to uptake organic dyes from water by promoting redox reactions during photocatalysis in the minimum time limit. 相似文献
94.
Nusrat Shaheen Muhammad Aadil Sonia Zulfiqar Humera Sabeeh Philips O. Agboola Muhammad Farooq Warsi Mohamed F. Aly Aboud Imran Shakir 《Ceramics International》2021,47(4):5273-5285
Here, we have fabricated the spinel binary-metal oxide (FeCo2O4) via a solvent-free and cost-effective approach. The nanocomposites of the as-fabricated binary-metal spinel oxide have been prepared with three different conductive-matrices, namely r-GO, CNTs, and PANI, via ultra-sonication approach. The spinel phase and surface functionalities of the fabricated FeCo2O4 sample have been confirmed via XRD and FT-IR analyses, respectively. The morphological-structure and elemental composition of the fabricated samples have been probed via FESEM and EDX results. The role of added conductive-matrices in the improvement of the electrical conductivities of the fabricated nanocomposites has been investigated via I–V experiments. The electrochemical experiments, conducted in half-cell configuration, showed that FeCo2O4/PANI nanocomposite exhibited the highest specific capacitance (658.9 Fg-1) than that of the remaining two nanocomposites. Furthermore, FeCo2O4/PANI nanocomposite exhibited excellent cyclic stability as it lost just 8.3% of its initial specific capacitance even after 3000 cyclic tests. The superior capacitive-activity of the FeCo2O4/PANI nanocomposite is accredited to its high conductivity, large surface area, and synergy effects between the pseudocapacitance derived from the PANI and FeCo2O4 nanostructure. The electrochemical and electrical measurements suggested that FeCo2O4/PANI nanostructure is an emerging contender for energy storage applications. 相似文献
95.
96.
ABSTRACTFeature selection is an important task to improve the classifier’s accuracy and to decrease the problem size. A number of methodologies have been presented for feature selection problems using metaheuristic algorithms. In this paper, an improved self-adaptive inertia weight particle swarm optimisation with local search and combined with C4.5 classifiers for feature selection algorithm is proposed. In this proposed algorithm, the gradient base local search with its capacity of helping to explore the feature space and an improved self-adaptive inertia weight particle swarm optimisation with its ability to converge a best global solution in the search space. Experimental results have verified that the SIW-APSO-LS performed well compared with other state of art feature selection techniques on a suit of 16 standard data sets. 相似文献
97.
Junaid Latief Shah Heena Farooq Bhat 《Information Security Journal: A Global Perspective》2020,29(1):14-29
ABSTRACTStateless Address Autoconfiguration (SLAAC) is one of the novel features introduced in IPv6 Neighbor Discovery Protocol (NDP) providing for self-configuration of nodes and supplementing the reduction of operational and deployment cost of networks. Although self-configuration elevates the idea of autonomy for network, it has also introduced vulnerabilities that require substantial solutions. The SLAAC is pivoted on the presumption that network consists of authentic and entrusted nodes, however with inception of public sector wireless networks; any node can affix to the link with trivial authentication and situation changes radically. Although some security extensions like IPsec or SeND have been proposed, but these security protocols have been reported to have serious limitations like complex cryptographic algorithms which negate their adoption. This paper revisits the stateless auto configuration process and discusses its inherent vulnerabilities. The paper surveys existing research and available defense mechanisms available to protect SLAAC. The paper also suggests some guidelines from existing literature which can further promote and supplement the research to secure the auto configuration process. Finally, a novel technique is proposed for securing IPv6 link layer communication against DoS and Man-in-the-Middle attack which can be used as an alternate approach for CGA and SeND protocol. 相似文献
98.
Ramesh Kumar Ahmad Umar Rajesh Kumar M.S. Chauhan Yas Al-Hadeethi 《Ceramics International》2021,47(5):6201-6210
ZnO–SnO2 nanocubes were used as promising material for efficient sensing of p-nitrophenol and faster photocatalytic degradations of dyes like methyl orange (MO), methylene Blue (MB) and acid orange 74 (AO74). ZnO–SnO2 nanocubes were prepared by the facile solution process at 50 °C using Zn(NO3)2·6H2O and SnCl2·2H2O as a precursor in the presence of ethylenediammine. The synthesized material was examined for its morphological, structural, crystalline, optical, vibrational, and compositional studies by using field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy. FESEM studies revealed the formation of well-defined ZnO–SnO2 nanocubes where the structural examinations revealed the formation of a crystalline tetragonal rutile phase for SnO2 with some crystal sites doped with Zn. The as-synthesized nanocubes were explored for their photocatalytic activities towards three different dye viz. MO, MB, and AO74. Practically, complete degradation of AO74 was seen within 4 minutes of photo-irradiation in the presence of 0.05 g ZnO–SnO2 nanocubes. However, 97.17% and 41.63% degradations were observed for MB and MO within 15 and 60 minutes, respectively. All the dye degradation processes followed the pseudo-first-order kinetic model. Moreover, the as-synthesized nanocubes were utilized to fabricate highly sensitive and selective fluorescent chemical sensor for the detection of p-nitrophenol (PNP). ZnO–SnO2 nanocubes showed a very low detection limit of 4.09 μM for the detection of PNP as calculated according to the 3σ IUPAC criteria. Further, the as-synthesized ZnO–SnO2 nanotubes were found to be highly selective for p-nitrophenol as compared to the other two isomers. 相似文献
99.
Noman Walayat Miguel Ángel Rincón Sobia Niaz Asad Nawaz Nadia Niaz Muhammad Zahid Farooq Ishtiaq Ahmad Pengkai Wang Zhongli Zhang 《International Journal of Food Science & Technology》2021,56(8):4009-4016
The effect of egg white protein (EWP) and β-cyclodextrin (β-CD) mixture was analysed on the myofibrillar proteins (MP) of Culter alburnus during a frozen storage at −18 °C for 60 days. Different proportions of EWP:β-CD mixture (0%, 2%, 4% and 6%) were added into MP to analyse their effect against oxidative changes. During the study, sulphydryl contents and Ca-ATPase activity (0.297 to 0.136 mmol g−1) decreased. Moreover, protein denaturation also prompted the surface hydrophobicity (11.47 to 32.06 μg) and carbonyls (26.36 to 49 mg.28 nmol mg−1) of control MP. A significant decline was observed in emulsifying properties. Besides, EWP:β-CD showed remarkable stability against oxidative changes, by significantly reducing the carbonyls (26.26 to 37.69 nmol mg−1) and surface hydrophobicity (11.51 to 20.31 μg) and also the decline of Ca-ATPase activity (0.29 to 0.19 mmol g−1). It can be concluded that EWP:β-CD (6%) is an efficient approach against oxidative changes in MP from Culter alburnus. 相似文献
100.
Advances in the field of medical sciences and medical technology, and
present-day challenges, such as an aging population, rising medical expenses, and
lifestyle-related diseases, have collectively catalyzed a research ecosystem termed
“smart wellness.” This article describes the establishment of a smart wellness service platform designed to empower individuals to create a sense of balance in
their lives. Step-by-step details include service model, design, and architectural
considerations. As a proof of concept, implementation details of a Health
Improvement and Management Systems (HIMS) Hub, a Smart Wellness Service
Platform deployed in six cities in South Korea, are presented. An on-site survey
conducted in Busan Metropolitan City reveals the percentage of satisfied users to
be 91.3%. Furthermore, data gathered from 27,236 physical evaluations of users
from a Busan city center over the period of April 2013 to May 2018 reveal that
males and females in their 50s and 60s account for the highest number of participants, while males in their 70s have a higher rate of participation than females
in the same age group. 相似文献