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51.
52.
Nidhi Nandu Mustafa Salih Hizir Neil M. Roberston Dr. Birol Ozturk Prof. Dr. Mehmet V. Yigit 《Chembiochem : a European journal of chemical biology》2019,20(14):1861-1867
Two-dimensional MoS2 nanoparticles (2D-nps) exhibit artificial enzyme properties that can be regulated at bio-nanointerfaces. We discovered that protein lipase is able to tune the peroxidase-like activity of MoS2 2D-nps, offering low-nanomolar, label-free detection and identification in samples with unknown identity. The inhibition of the peroxidase-like activity of the MoS2 2D-nps was demonstrated to be concentration dependent, and as low as 5 nm lipase was detected with this approach. The results were compared with those obtained with several other proteins that did not display any significant interference with the nanozyme behavior of the MoS2 2D-nps. This unique response of lipase was characterized and exploited for the successful identification of lipase in six unknown samples by using qualitative visual inspection and a quantitative statistical analysis method. The developed methodology in this approach is noteworthy for many aspects; MoS2 2D-nps are neither labeled with a signaling moiety nor modified with any ligands for signal readout. Only the intrinsic nanozyme activity of the MoS2 2D-nps is exploited for this detection approach. No analytical equipment is necessary for the visual detection of lipase. The synthesis of the water-soluble MoS2 2D-nps is low costing and can be performed in bulk scale. Exploring the properties of 2D-nps and their interactions with biological materials reveals highly interesting yet instrumental features that offer the development of novel bioanalytical approaches. 相似文献
53.
Muhammad Zia ul Mustafa Hilmi bin Mukhtar Nik Abdul Hadi Md Nordin Hafiz Abdul Mannan Rizwan Nasir Nabilah Fazil 《化学工程与技术》2019,42(12):2580-2593
Flue gas emissions and the harmful effects of these gases urge to separate and capture these unwanted gases. Ionic liquids due to negligible vapor pressure, thermal stability, and wide electrochemical stability have expanded its application in gas separations. A comprehensive overview of the recent developments and applications of ionic liquid membranes (ILMs) for gas separation is given. The three general classifications of ILMs, such as supported ionic liquid membranes (SILMs), ionic liquid polymeric membranes (ILPMs), and ionic liquid mixed‐matrix membranes (ILMMMs) along with their applications, for the separation of various mixed gases systems is discussed in detail. Furthermore, issues, challenges, computational study, and future perspectives for ILMs are also considered. 相似文献
54.
Merve Küçükoflaz Berna Saraçoğlu Kaya Mustafa Oguzhan Caglayan 《Polymer-Plastics Technology and Engineering》2019,58(7):765-775
In this study, we synthesized poly (vinyl acetate-co-divinyl benzene) microspheres with various monomer/cross-linker contents for oral/topical sustained drug release applications and determined the micromechanical properties by nanoindentation. Compression elastic moduli of materials were calculated by using the limited depth of indentation according to Hertz elastic deformation model and presented as the histogram of multiple data. In terms of drug release practices, poly (VAc-co-DVB) microspheres with a high DVB content, especially in topical applications, are expected to carry drugs under mechanical stresses of less than 1.0 GPa. 相似文献
55.
Experiments involving the supercritical extraction of bitumen using various solvent mixtures were carried out in a 2-l batch autoclave to determine the effect of modifier type and concentration on deasphalted oil (DAO) yield and quality. Athabasca bitumen was used as the feedstock and n-pentane was used as the primary solvent for extraction. Acetone, toluene, methanol and ethyl acetate were each added to n-pentane as modifiers in different concentrations to form the solvent mixtures. Extraction temperatures and pressures were maintained at around 200 °C and 1100 psi to achieve supercritical conditions for solvents, and the solvent-to-feed volume ratio was kept around 6.5. Higher DAO yields were obtained with increasing modifier concentrations in n-pentane. DAO yields ranged from 79 to 92 wt.% of the bitumen, with n-pentane/toluene mixtures providing the highest yields and n-pentane/methanol mixtures producing the lowest. Increases in DAO yield were accompanied by higher nickel, vanadium, nitrogen, sulfur and microcarbon residue content in DAO. Moreover, it was found that n-pentane/methanol and n-pentane/acetone solvent mixtures had lower selectivities for metals impurities than the other modifiers, while n-pentane/toluene had the highest selectivities. 相似文献
56.
In the present work, thiourea‐formaldehyde (TUF) chelating resin was synthesized and used in the adsorptions of selenite (SeO) and selenate (SeO) ions. The effects of initial acidity and initial selenium concentrations on the adsorptions were examined by batch technique. The synthesized resin was applied to the elemental analysis to determine its composition. FT‐IR spectra and SEM/EDS were also recorded before and after selenite adsorption. It was found that selenite and selenate ions were adsorbed onto TUF resin at strong acidic conditions (3–5M HCl). The adsorption capacities of the resin were calculated as 833.3 mg g?1 TUF resin for selenite ions and 526.3 mg g?1 TUF resin for selenate. All the adsorption data obtained for both selenite and selenate ions fitted well to the Langmuir isotherm. It was seen that the adsorption mechanisms in the both adsorptions were governed by the reduction of selenite or selenate to elemental selenium, Se0. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011. 相似文献
57.
Thiourea‐formaldehyde (TUF), a well‐known chelating resin, has been synthesized and it was used in the adsorption, selective separation, and concentration of Pd(II) ions from Fe(III), Co(II) Ni(II), and Cu(II) base metal ions. The composition of the synthesized resin was determined by elemental analysis. The effect of initial acidity/pH and the adsorption capacity for Pd(II) ions were studied by batch technique. The adsorption and separation of Pd(II) were then examined by column technique. FTIR spectra and SEM/EDS analysis were also recorded before and after the adsorption of Pd(II). The optimum pH was found to be 4 for the adsorption. The adsorption data fitted well to the Langmuir isotherm. The maximum adsorption capacity of the TUF resin for Pd(II) ions was found to be 31.85 mg g−1 (0.300 mmol g−1). Chelating mechanism was effective in the adsorption. Pd(II) ions could be separated efficiently from Fe(III), Cu(II), Ni(II), and Co(II) ions using TUF resin. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
58.
Compressive mechanical properties of sawdust/high density polyethylene composites under various strain rate loadings 下载免费PDF全文
Haliza Jaya Mohd Firdaus Omar Hazizan Md Akil Zainal Arifin Ahmad Nik Noriman Zulkepli Mohd Mustafa Al Bakri Abdullah 《乙烯基与添加剂工艺杂志》2018,24(2):162-173
This article is concerned with the static and dynamic mechanical properties of high‐density polyethylene (HDPE) reinforced with sawdust (SD) at a strain rate of up to 103 s?1. In this study, the static and dynamic properties of HDPE/SD composites with different filler loadings of 5, 10, 15, 20, and 30 wt% SD were deliberated at different levels of strain rates (0.001, 0.01, 0.1, 650, 900, and 1100 s?1) using a conventional universal testing machine and the split Hopkinson pressure bar apparatus. The results showed that the stress–strain curves, yield behavior, stiffness, and strength properties of the HDPE/SD composites were strongly affected by both the strain rate and the filler loadings. Furthermore, the rate sensitivityof the HDPE/SD composites showed a great dependency on the applied strain rate, increasing as the strain rate increased. However, the thermal activation values showed a contrary trend. Meanwhile, for the postdamage analysis, the results showed that the applied strain rates influenced the deformation behavior of the tested HDPE/SD composites. Moreover, for the fractographic analysis at dynamic loading, the composites showed that all the specimens underwent a severe catastrophic deformation. J. VINYL ADDIT. TECHNOL., 24:162–173, 2018. © 2016 Society of Plastics Engineers 相似文献
59.
Onur Coban Mustafa Ozgur Bora Egemen Avcu Tamer Sinmazcelik 《Polymer Composites》2011,32(11):1766-1771
In this study, annealing influence on crystallization and scratch behavior of neat and multi‐wall carbon nanotube (MWNT) reinforced poly(ether ether ketone) (PEEK) nanocomposites have been investigated. Crystallization behavior of normal and annealed samples was investigated by using differential scanning calorimeter (DSC). Scratch behavior of normal and annealed samples was investigated by using micro scratch tester. In DSC analysis, it was detected that, melting enthalpy of annealed neat PEEK was increased sharply when compared to neat PEEK. Melting enthalpies of annealed PEEK nanocomposites prepared with addition of up to 1 wt% MWNT were increased with a decreased trend. However, nanocomposites with higher contents of MWNTs (>1 wt%) were dramatically affected by annealing process and melting enthalpy decreased sharply. Friction coefficient values of “annealed MWNT reinforced PEEK composites” were found to be lower than “normal PEEK composites.” Annealing process affects scratch hardness of both annealed and MWNT reinforced PEEK. Annealed nanocomposites with various MWNT concentrations showed higher scratch hardness values than normal PEEK nanocomposites. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers 相似文献
60.
Mustafa Tutak 《Coloration Technology》2011,127(5):340-345
In this study, the effect of cationisation on optical whitening was examined. For this purpose, the whiteness index and whiteness tint of optically whitened pre‐cationised knitted cotton fabrics were analysed. The cationisation and optical whitening processes were carried out under different concentration levels, using the exhaustion method. The whiteness index and whiteness tint were calculated after colour measurements were taken. The experimental results were also analysed statistically using ANOVA. The whiteness index obtained from cationised fabric was lower than that of non‐cationised fabrics. While the whiteness tint of cationised cotton fabric had a blue to greenish nuance, the non‐cationised fabric had a reddish nuance. 相似文献