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71.
As the use of automation in industry accelerates, the development of flexible, electrically conducting materials with the requisite environmental resilience for impact‐resistant sensors, foldable electronics, and electrostatic shielding are needed; simultaneously, recyclability for these materials remains a crucial attribute. Traditional conductive stretchable materials, such as rubbers, are not recyclable, and hydrogel materials have limited applications due to water evaporation and operating temperature range. Comparatively, organogels can be formulated with enhanced tunability, matrix recyclability, and the ability to support many conductive fillers. Here, rheology, mechanical testing, and electrochemical impedance spectroscopy (EIS) characterize the nanoscale interactions between carbon fillers, the liquid phase, and the network matrix in hemiaminal dynamic covalent network (HDCN) organogels. HDCN chemical equilibria are shown to strongly influence macroscopic gel properties, while HDCN composites exhibit very high conductivities up to 9.95 mS cm?1 appropriate for sensing applications, demonstrating promise as recyclable alternatives for conductive stretchable materials. 相似文献
72.
This paper examines the anticorrosion characteristics of three different benzimidazole derivatives towards mild steel in 0.5?M hydrochloric acid at temperature ranges from 303 to 323?K. The benzimidazole derivatives used for the screening studies are 2-(2-methyl-1H-benzimidazol-1-yl) acethydrazide (EMBAH), 2-(2-ethyl-1H-benzimidazol-1-yl) acethydrazide (EEBAH) and 2-(2-propyl-1H-benzimidazol-1-yl) acethydrazide (EPBAH). The corrosion inhibition was investigated by weight loss, electrochemical impedance spectroscopy and potentiodynamic polarization studies. The adsorption interaction between metal and inhibitor followed Langmuir adsorption isotherm. The Gibb’s free energy values clarify the spontaneous nature of adsorption process. The temperature dependence of inhibition efficiency was explained by considering thermodynamic parameters of adsorption and kinetic parameters of corrosion. These inhibitors showed good efficiency at lower as well as moderately higher temperatures. Quantum chemical calculations were done using DFT at the B3LYP/6-31G1 level to study the electronic properties of the molecules for correlating the inhibitive effect and molecular structure. 相似文献
73.
Annette Abraham Ajoe John Kattoor Tom Saldeen 《Critical reviews in food science and nutrition》2019,59(17):2831-2838
AbstractVitamin E is a lipid soluble vitamin comprising of eight natural isoforms, namely, α, β, δ, γ isoforms of tocopherol and α, β, δ, γ isoforms of tocotrienol. Many studies have been performed to elucidate its role in cancer. Until last decade, major focus was on alpha tocopherol and its anticancer effects. However, major clinical trials using alpha-tocopherol like SELECT trial and ATBC trial did not yield meaningful results. Hence there was a shift of focus to gamma-tocopherol, delta-tocopherol and tocotrienol. Unlike alpha-tocopherol, gamma-tocopherol and delta-tocopherol can scavenge reactive nitrogen species in addition to reactive oxygen species. Antiangiogenic effect, inhibition of HMG CoA reductase enzyme and inhibition of NF-κB pathway make the anti-cancer effects of tocotrienols unique compared to other vitamin E isoforms. Preclinical research on non-alpha tocopherol isoforms of vitamin E showed promising data on their anticancer effects. In this review, we deal with the current understanding on the potential mechanisms involved in the anticancer effects of vitamin E and the controversies in this field over last three decades. We also highlight the need to conduct further research on the anticancer effects of non-alpha-tocopherol isoforms in larger population and clinical setting. 相似文献
74.
Xinghong Duo Lingchuang Bai Jun Wang Jintang Guo Xiangkui Ren Shihai Xia Wencheng Zhang Abraham Domb Yakai Feng 《Frontiers of Chemical Science and Engineering》2021,15(1):220-220
The authors regret that there was an error in our publication.Considering Lingchuang Bai made great contributions to this work,Xinghong Duo and Lingchuang Bai should be co-first authors,but there was no statement that“Xinghong Duo and Lingchuang Bai contributed equally to this work”.The authors would like to apologize for any inconvenience caused. 相似文献
75.
76.
The support of voice communication is fundamental in the deployment of an ad hoc network for the battlefield or emergency response. We use the QoS requirements of voice to identify factors influencing its communication, and validate their significance through statistical analysis. Based on the results, we propose an opportunistic protocol within a cross-layer framework that adapts these factors at different time scales. Hop-by-hop adaptation exploits the PHY/MAC interaction to improve the use of the spectral resources through opportunistic rate-control and packet bursts, while end-to-end adaptation exploits the LLC/application interaction to control the demand per call through voice coding and packet size selection. Our objective is to maximize the number of calls admitted while minimizing loss of quality. We evaluate the performance of the protocol in simulation with real audio traces using both quantitative and mean opinion score (MOS) audio quality metrics, comparing to several standard voice codecs. The results indicate that: (i) compression and packet-size selection play a critical role in supporting QoS over ad hoc networks; (ii) header compression is needed to limit the overhead per packet especially over longer paths; (iii) good voice quality is achieved even in strenuous network conditions. 相似文献
77.
In vitro digestibility of phenolic compounds from edible fruits: could it be explained by chemometrics?
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Francisco J. Olivas‐Aguirre Marcela Gaytán‐Martínez Sandra O. Mendoza‐Díaz Gustavo A. González‐Aguilar Joaquín Rodrigo‐García Nina del Rocío Martínez‐Ruiz Abraham Wall‐Medrano 《International Journal of Food Science & Technology》2017,52(9):2040-2048
The health benefits of phenolic compounds depend on the ingested amount, molecular diversity and gastrointestinal digestibility. The phenolic profile of eight fruits (blackberry, blueberry, strawberry, raspberry, mulberry, pomegranate, green and red globe grapes) was chemometrically associated with their in vitro digestibility (oral, gastric, intestinal). Extractable phenols, flavonoids and anthocyanins strongly correlated with each other (r ≥ 0.84), proanthocyanidins with anthocyanins (r = 0.62) and hydrolysable phenols with both extractable phenols (r = 0.45) and proanthocyanidins (r = ?0.54). Two principal components explained 93% of the variance [61% (free‐phenols), 32% (bounded‐phenols)], and four clusters were confirmed by hierarchical analysis, based in their phenolic richness (CLT 1‐4: low to high) and molecular diversity. In vitro digestibility of extractable phenols and flavonoids was blackberry (CLT‐4)> raspberry (CLT‐2)> red grape (CLT‐1) related to their phenolic richness (r ≥ 0.96; P < 0.001), but anthocyanins’ digestibility was pH‐dependent. Chemometrics is useful to predict the in vitro digestibility of phenolic compounds in the assayed fruits. 相似文献
78.
Gomadurai Chinnasamy Saravanan Kaliannan Abraham Eldho Deepa Nadarajan 《Korean Journal of Chemical Engineering》2016,33(4):1181-1185
The objective of the present study was to design, fabricate and evaluate the performance of a novel airi-nducing impeller system with a specially designed air-inducing tube-set. The novel air-inducing impeller system, when attached to a conventional baffled agitated vessel, could convert it into an air-inducing reactor. Water was used as the working fluid and the characteristics of the impeller system such as critical speed, power consumption and gas holdup were investigated by varying the gas free liquid level, orifice immersion depth, bottom clearance and impeller speed. Results showed that this novel air-inducing impeller system induced the air at speeds lower than the critical speeds reported by most of the investigators in the literature. 相似文献
79.
80.
Aarthy K Chindhanaiselvam Anitha Priya John Abraham Nambirajan Subramanian 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(19):2823-2829
Dwarf Poinciana (Caesalpinia pulcherrima) seeds are studied for first time for the extraction of bio-oil. The dried and crushed seeds are optimized for maximum yield of bio-oil with a series of polar and nonpolar solvents and recovered by a simple distillation process. Methanol is found to yield the maximum bio-oil. The fatty acid analysis of bio-oil reveals the prevalence of linoleic acid (54.67%), followed by palmitic acid (16.9%), stearic acid (12.5%), and oleic acid (10.32%). Basic fuel properties like specific gravity, viscosity, refractive index, iodine value, saponification value, fire point, flash point, pour point, and calorific value are studied. 相似文献