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51.
In recent times, the evolution of blockchain technology has got huge attention from the research community due to its versatile applications and unique security features. The IoT has shown wide adoption in various applications including smart cities, healthcare, trade, business, etc. Among these applications, fitness applications have been widely considered for smart fitness systems. The users of the fitness system are increasing at a high rate thus the gym providers are constantly extending the fitness facilities. Thus, scheduling such a huge number of requests for fitness exercise is a big challenge. Secondly, the user fitness data is critical thus securing the user fitness data from unauthorized access is also challenging. To overcome these issues, this work proposed a blockchain-based load-balanced task scheduling approach. A thorough analysis has been performed to investigate the applications of IoT in the fitness industry and various scheduling approaches. The proposed scheduling approach aims to schedule the requests of the fitness users in a load-balanced way that maximize the acceptance rate of the users’ requests and improve resource utilization. The performance of the proposed task scheduling approach is compared with the state-of-the-art approaches concerning the average resource utilization and task rejection ratio. The obtained results confirm the efficiency of the proposed scheduling approach. For investigating the performance of the blockchain, various experiments are performed using the Hyperledger Caliper concerning latency, throughput, resource utilization. The Solo approach has shown an improvement of 32% and 26% in throughput as compared to Raft and Solo-Raft approaches respectively. The obtained results assert that the proposed architecture is applicable for resource-constrained IoT applications and is extensible for different IoT applications. 相似文献
52.
Adeeba Jamil Mohd. Aamir Mirza Md. Khalid Anwer Pragya S. Thakur Saad M. Alshahrani Abdullah S. Alshetaili 《Drug development and industrial pharmacy》2019,45(5):745-753
Despite the ongoing extensive research, cancer therapeutics still remains an area with unmet needs which is hampered by shortfall in the development of newer medicines. The present study discusses a nano-based combinational approach for treating solid tumor. Dual-loaded nanoparticles encapsulating gemcitabine HCl (GM) and simvastatin (SV) were fabricated by double emulsion solvent evaporation method and optimized. Optimized nanoparticles showed a particle size of 258?±?2.4?nm, polydispersity index of 0.32?±?0.052, and zeta potential of ?12.5?mV. The size and the morphology of the particles wee further confirmed by transmission electron microscopy (TEM) and scanning electron microscopy, respectively of the particles. The entrapment efficiency of GM and SV in the nanoparticles was 38.5?±?4.5% and 72.2?±?5.6%, respectively. The in vitro release profile was studied for 60?h and showed Higuchi release pattern. The cell toxicity was done using MTT assay and lower IC50 was obtained with the nanoparticles as compared to the pure drug. The bioavailability of GM and SV in PLGA nanoparticles was enhanced by 1.4-fold and 1.3-fold respectively, compared to drug solution. The results revealed that co-delivery of GM and SV could be used for its oral delivery for the effective treatment of pancreatic cancer. 相似文献
53.
Jian Zhang Lulu Huang Chen Zhu Chongjian Zhou Bushra Jabar Jimin Li Xiaoguang Zhu Ling Wang Chunjun Song Hongxing Xin Di Li Xiaoying Qin 《Advanced materials (Deerfield Beach, Fla.)》2019,31(52)
Chalcopyrite compound CuGaTe2 is the focus of much research interest due to its high power factor. However, its high intrinsic lattice thermal conductivity seriously impedes the promotion of its thermoelectric performance. Here, it is shown that through alloying of isoelectronic elements In and Ag in CuGaTe2, a quinary alloy compound system Cu1?xAgxGa0.4In0.6Te2 (0 ≤ x ≤ 0.4) with complex nanosized strain domain structure is prepared. Due to strong phonon scattering mainly by this domain structure, thermal conductivity (at 300 K) drops from 6.1 W m?1 K?1 for the host compound to 1.5 W m?1 K?1 for the sample with x = 0.4. As a result, the optimized chalcopyrite sample Cu0.7Ag0.3Ga0.4In0.6Te2 presents an outstanding performance, with record‐high figure of merit (ZT) reaching 1.64 (at 873 K) and average ZT reaching 0.73 (between ≈300 and 873 K), which are ≈37 and ≈35% larger than the corresponding values for pristine CuGaTe2, respectively, demonstrating that such domain structure arising from isoelectronic multielement alloying in chalcopyrite compound can effectively suppress its thermal conductivity and elevate its thermoelectric performance remarkably. 相似文献
54.
55.
Microsystem Technologies - The design and fabrication of nichrome based coplanar microheater for LPG sensing applications is presented in this work. Nichrome based coplanar microheater is... 相似文献
56.
Synthesis of poly(acrylonitrile‐co‐divinylbenzene‐co‐vinylbenzyl chloride)‐derived hypercrosslinked polymer microspheres and a preliminary evaluation of their potential for the solid‐phase capture of pharmaceuticals
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Nur Nida Syamimi Subri Peter A. G. Cormack Siti Nurul Ain Md. Jamil Luqman Chuah Abdullah Rusli Daik 《应用聚合物科学杂志》2018,135(2)
Poly[acrylonitrile (AN)‐co‐divinylbenzene (DVB)‐co‐vinylbenzyl chloride (VBC)] terpolymers were synthesized by precipitation polymerization in the form of porous polymer microspheres. The poly(AN‐co‐DVB‐co‐VBC) polymers were then hypercrosslinked, via a Friedel‐Crafts reaction with FeCl3 in nitrobenzene, to provide a significant uplift in the specific surface areas of the polymers. FTIR spectra of the hypercrosslinked poly(AN‐co‐DVB‐co‐VBC)s showed that the chloromethyl groups derived from VBC were consumed by the Friedel‐Crafts reactions, which was consistent with successful hypercrosslinking. Hypercrosslinking installed a number of new, small pores into the polymers, as evidenced by a dramatic increase in the specific surface areas upon hypercrosslinking (from ~530 to 1080 m2 g?1). The hypercrosslinked polymers are very interesting for a range of applications, not least of all for solid‐phase extraction (SPE) work, where the convenient physical form of the polymers (beaded format), their low mean particle diameters, and narrow particle size distributions, as well as their high specific surface areas and polar character (arising from the AN residues), make them attractive candidates as SPE sorbents. In this regard, in a preliminary study one of the hypercrosslinked polymers was utilized as an SPE sorbent for the capture of the polar pharmaceutical diclofenac from a polar environment. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45677. 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.
Fahd Jamshaid Adnan Ahmad Muhammad Adrees Sadia Sagar Iqbal Hira Zaheer Tahir Jamil Javaid Ahmad Tousif Hussain 《Iranian Polymer Journal》2017,26(12):913-927
The incorporation of functionalized nanoscale fillers into traditional glass fiber/unsaturated polyester (GF/UPE) composites provides a more robust mechanical attributes. The current study demonstrates the potential of 3-mercaptopropyl trimethoxysilane (MPTS)-functionalized carbon black (f-CB) for enhancing the thermo-mechanical properties of GF composites. The composites infused with 1, 3 and 5 wt% of pristine and MPTS-functionalized CB were fabricated by hand lay-up and hot press processing. Tensile testing, interlaminar shear strength (ILSS) testing and dynamic mechanical analysis were used to evaluate the performance of nanocomposites. Fourier transform infrared spectroscopy validated the MPTS functionalization of CB. Pristine CB-loaded nanocomposites exhibited marginal improvement in ultimate tensile strength (UTS), ILSS and thermo-mechanical properties. However, with the addition of f-CB, the improvement in all the studied properties was more substantial. The inclusion of 5 wt% f-CB increased the elastic modulus and UTS by 16 and 22%, respectively, whereas the ILSS was enhanced by 36%, in comparison to the neat GF composite. The scanning electron microscope analysis of fractured ILSS samples revealed better fiber-matrix adhesion and compatibility in f-CB-loaded nanocomposites. At the same filler weight percentage, the storage modulus at 25 °C was ~ 19% higher than that of neat composite. The f-CB inclusion resulted in increment of T g by ~ 13 °C over the T g of neat GF/UPE composite (~ 109 °C). These improvements were due to the chemical connection of f-CB to the UPE matrix and GF surface. With such improvements in thermal and mechanical properties, these nanocomposites can replace the conventional GF composites with prominent improvements in performance. 相似文献
59.
Couto CI Natour J Carvalho AB 《Hemodialysis international. International Symposium on Home Hemodialysis》2008,12(1):66-72
Fibromyalgia syndrome (FMS) is characterized by widespread musculoskeletal pain. It has negative effects on quality of life and has been poorly investigated in specific populations. Our aim was to determine the prevalence of FMS in Brazilian hemodialysis (HD) patients and to investigate its effects on the quality of life. We investigated 311 patients on HD who were submitted to physical examination towards the classification of FMS. All subjects from FMS and control groups were submitted to laboratorial investigation and completed questionnaires of quality of life. The prevalence of FMS was 3.9%, which was close to that of the general population. Most patients were females and from non-Caucasian races. No difference between FMS and control groups was observed regarding race, dialysis adequacy, nutritional status and level of schooling. Ionized calcium was higher in the FMS group than in the control group. There was no association between FMS and secondary hyperparathyroidism. On the other hand, FMS was associated with worse quality of life, depression and anxiety. In conclusion, the prevalence of FMS in HD patients was similar to that of the general population. It was associated with decreasing quality of life in HD patients, in addition to higher degrees of depression and anxiety. No laboratory tests could identify FMS patients on HD. Fibromyalgia syndrome subsequently follows without a well-established mechanism of pathogenesis, and seems to be due to multifactorial causes. Its true impact on the quality of life of HD patients deserves more attention by nephrologists. 相似文献