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941.
Muhammad Adil Hasnah Mohd Zaid Lee Kean Chuan Noor Rasyada Ahmad Latiff 《Journal of Dispersion Science and Technology》2017,38(4):570-576
The effect of dielectric loss on the electrorheological (ER) characteristic of dielectric nanofluids under shear was studied. When nanofluids are activated by an applied electric field, it behaves like a non-Newtonian fluid under ER effect by creating the chains of nanoparticles. ER characteristics of ZnO and Al2O3 nanofluids with various nanoparticles concentration (0.1, 0.05, 0.01 wt%) were measured. For this purpose, a solenoid-based electromagnetic (EM) transmitter was used under different propagation media including air, tap water, and salt water. The result shows that all the nanofluids exhibit pseudo-plastic behavior, while the electric field causes a significant increase in viscosity in the presence of tap water, followed by salt water. Additionally, the viscosity of nanofluid shows a high dependence on particle loading. A possible mechanism was also proposed to describe the effect of dielectric properties on the ER behavior of dielectric nanofluids. 相似文献
942.
Nurshazliana Othman Vuanghao Lim Muggundha Raoov Ramachandran Mohd Marsin Sanagi Sazlinda Kamaruzaman Yuichiro Hirota Norikazu Nishiyama Noorfatimah Yahaya 《Chromatographia》2017,80(10):1553-1562
A rapid, simple, and efficient method using ultrasound-assisted emulsification microextraction combined with dispersive micro-solid phase extraction (USAE-D-µ-SPE) was developed for detection and quantification of three azole antifungals in milk samples by high-performance liquid chromatography diode array detector. In this study, mesoporous carbon, COU-2, was used as sorbent in USAE-D-µ-SPE for the extraction and preconcentration of analytes. Several important experimental parameters, including type of deproteinized solvents, desorption time, type of extraction solvents, volume of extraction solvent, extraction time, emulsification time, sample pH, salt addition, and mass of COU-2 sorbent, were optimized using spiked milk samples. Under the optimum extraction and detection conditions, three azole antifungals, namely ketoconazole, clotrimazole, and miconazole, were determined within 20 min, with good linearity of matrix-matched calibration in the range of 0.5–5000.0 µg L?1 with coefficient of determination, r 2 ≥ 0.9943. The method showed limits of detection and limits of quantification of all analytes in the range of 0.15–3.0 and 0.5–10.0 µg L?1, respectively. Good repeatability with RSDs <15% (n = 3) and satisfactory relative recoveries (83.3–111.1%) were obtained for spiked azole antifungal drugs in milk. The results reveal that the developed USAE-D-µ-SPE method was a simple, rapid, efficient, environmentally friendly, and practicable method for the determination of azole antifungals in milk samples. 相似文献
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944.
945.
Chemisorption,Morphology, and Structure of a n‐Type Perylene Diimide Derivative at the Interface with Gold: Influence on Devices from Thin Films to Single Molecules
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Francesca Ciccullo Sabine‐Antonia Savu Dr. Andrea Gerbi Maximilian Bauer Dr. Ruslan Ovsyannikov Antonio Cassinese Prof. Thomas Chassé Dr. Maria Benedetta Casu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(9):3766-3771
We have investigated thin films of a perylene diimide derivative with a cyano‐functionalized core (PDI‐8CN2) deposited on Au(111) single crystals from the monolayer to the multilayer regime. We found that PDI‐8CN2 is chemisorbed on gold. The molecules experience a thickness‐dependent reorientation, and a 2D growth mode with molecular stepped terraces is achieved adopting low deposition rates. The obtained results are discussed in terms of their impact on field effect devices, also clarifying why the use of substrate/contact treatments, decoupling PDI‐8CN2 molecules from the substrate/contacts, is beneficial for such devices. Our results also suggest that perylene diimide derivatives with CN bay‐functionalization are very promising candidates for single‐molecule electronic devices. 相似文献
946.
Ahmed Aziz Ahmad Sayeed Ur-Rahman Mahfooz Tajuddin Tamboli E. Verma Ranbir Afzal Mohd Mehra Prahlad Singh 《平面色谱法杂志一现代薄层色谱法》2015,28(4):287-293
JPC – Journal of Planar Chromatography – Modern TLC - Bacoside A, a triterpenoid saponin, is a major constituent isolated from Bacopa monnieri (L.) Wettst. (Scrophulariaceae), used as a... 相似文献
947.
Chemistry of Natural Compounds - 相似文献
948.
Muhammad Farhan Nazarudin Nurul Haziqah Alias Seentusha Balakrishnan Wan Nurazween Izatee Wan Hasnan Nur Amirah Izyan Noor Mazli Mohd Ihsanuddin Ahmad Ina-Salwany Md Yasin Azizul Isha Mohamed Aliyu-Paiko 《Molecules (Basel, Switzerland)》2021,26(17)
Recent increased interest in seaweed is motivated by attention generated in their bioactive components that have potential applications in the functional food and nutraceutical industries. In the present study, nutritional composition, metabolite profiles, phytochemical screening and physicochemical properties of freeze-dried brown seaweed, Sargassum polycystum were evaluated. Results showed that the S. polycystum had protein content of 8.65 ± 1.06%, lipid of 3.42 ± 0.01%, carbohydrate of 36.55 ± 1.09% and total dietary fibre content of 2.75 ± 0.58% on dry weight basis. The mineral content of S. polycystum including Na, K, Ca, Mg Fe, Se and Mn were 8876.45 ± 0.47, 1711.05 ± 0.07, 1079.75 ± 0.30, 213.85 ± 0.02, 277.6 ± 0.12, 4.70 ± 0.00 and 4.45 ± 0.00 mg 100/g DW, respectively. Total carotenoid, chlorophyll a and b content in S. polycystum were detected at 45.28 ± 1.77, 141.98 ± 1.18 and 111.29 µg/g respectively. The total amino acid content was 74.90 ± 1.45%. The study revealed various secondary metabolites and major constituents of S. polycystum fibre to include fucose, mannose, galactose, xylose and rhamnose. The metabolites extracted from the seaweeds comprised n-hexadecanoic acid, 1,2-benzenedicarboxylic acid, mono(2-ethylhexyl) ester, benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy- methyl ester, 1-dodecanol, 3,7,11-trimethyl-, which were the most abundant. The physicochemical properties of S. polycystum such as water-holding and swelling capacity were comparable to several commercial fibre-rich products. In conclusion, results of this study indicate that S. polycystum is a potential candidate as functional food sources for human consumption and its cultivation needs to be encouraged. 相似文献
949.
Mohanapriya Gunasekharan Tae-Ik Choi Yaya Rukayadi Muhammad Alif Mohammad Latif Thiruventhan Karunakaran Siti Munirah Mohd Faudzi Cheol-Hee Kim 《Molecules (Basel, Switzerland)》2021,26(17)
Bacterial infections are regarded as one of the leading causes of fatal morbidity and death in patients infected with diseases. The ability of microorganisms, particularly methicillin-resistant Staphylococcus aureus (MRSA), to develop resistance to current drugs has evoked the need for a continuous search for new drugs with better efficacies. Hence, a series of non-PAINS associated pyrrolylated-chalcones (1–15) were synthesized and evaluated for their potency against MRSA. The hydroxyl-containing compounds (8, 9, and 10) showed the most significant anti-MRSA efficiency, with the MIC and MBC values ranging from 0.08 to 0.70 mg/mL and 0.16 to 1.88 mg/mL, respectively. The time-kill curve and SEM analyses exhibited bacterial cell death within four hours after exposure to 9, suggesting its bactericidal properties. Furthermore, the docking simulation between 9 and penicillin-binding protein 2a (PBP2a, PDB ID: 6Q9N) suggests a relatively similar bonding interaction to the standard drug with a binding affinity score of −7.0 kcal/mol. Moreover, the zebrafish model showed no toxic effects in the normal embryonic development, blood vessel formation, and apoptosis when exposed to up to 40 µM of compound 9. The overall results suggest that the pyrrolylated-chalcones may be considered as a potential inhibitor in the design of new anti-MRSA agents. 相似文献
950.
In this article, we propose an alternative approach of the generalized and improved (G'/G)-expansion method and build some new exact traveling wave solutions of three nonlinear evolution equations, namely the Boiti- Leon-Pempinelle equation, the Pochhammer-Chree equations and the Painleve integrable Burgers equation with free parameters. When the free parameters receive particular values, solitary wave solutions are constructed from the traveling waves. We use the Jacob/elliptic equation as an auxiliary equation in place of the second order linear equation. It is established that the proposed algorithm offers a further influential mathematical tool for constructing exact solutions of nonlinear evolution equations. 相似文献