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131.
Sabine Beuermann Muhammad Imran‐ul‐Haq 《Journal of polymer science. Part A, Polymer chemistry》2007,45(23):5626-5635
For the first time, stabilizer‐free vinylidene fluoride (VDF) homopolymerizations were carried out in homogenous phase with supercritical CO2 using the conventional initiator di‐tert butyl peroxide (DTBP). In‐line FT‐NIR spectroscopy showed that complete monomer conversion may be obtained. Molecular weights were determined via size‐exclusion chromatography and polymer endgroup analysis by 1H‐NMR spectroscopy. The number average molecular weights were below 104 g mol?1 and polydispersities ranged from 3.1 to 5.7 depending on DTBP and VDF concentration. For allowing isothermal reaction, high CO2 contents ranging from 61 to 83 wt % were used. The high‐temperature and high‐pressure conditions required for homogeneous polymerization did not alter the amount of defects in VDF chaining. Scanning electron microscopy indicated that regular stack‐type particles are obtained upon expansion of the homogeneous polymerization mixture. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5626–5635, 2007 相似文献
132.
Imran Mohammad Iqubal Mohammad Kashif Ahmad Sayeed Ali Javed Baboota Sanjula 《平面色谱法杂志一现代薄层色谱法》2019,32(5):393-400
JPC – Journal of Planar Chromatography – Modern TLC - A simple, sensitive, specific, rapid, and accurate high-performance thin-layer chromatographic (HPTLC) method has been developed... 相似文献
133.
Dr. Raheela Naz Prof. Qinglei Liu Dr. Waseem Abbas Dr. Muhammad Imtiaz Dr. Imran Zada Dr. Javed Ahmad Dr. Tengfei Li Prof. Jiajun Gu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(70):16054-16062
A new ternary composite of 1T-molybdenum disulfide, hexagonal tungsten trioxide, and reduced graphene oxide (M-W-rGO) is synthesized by using a one-pot hydrothermal process. The synergetic effect of 1T-MoS2 and hexa-WO3 nanoflowers improves the electrochemical performance for supercapacitors by inducing additional active sites and hexagonal tunnels, respectively, which lead to high storage capacity and easy transfer of electrolyte ions. The ternary M-W-rGO composite has a high specific capacitance of 836 F g−1 at 1 A g−1, which is nearly twice that of binary composites of M-rGO and W-rGO with high capacitance retention of 86.35 % after 3000 cycles at a high current density of 5 A g−1. This study provides a new ternary composite that can be used as an electrode material for high-performance supercapacitors. 相似文献
134.
AL-Jawad Selma M. H. Imran Natheer Jamal Aboud Kahlaa H. 《Journal of Sol-Gel Science and Technology》2021,100(3):423-439
Journal of Sol-Gel Science and Technology - Mn-CdS nanoflowers were successfully deposited using hydrothermal technique at 150 °C for 2 h. The effect of changing the dopant... 相似文献
135.
Glasses are known to exhibit quantitative universalities at low temperatures, the most striking of which is the ultrasonic attenuation coefficient Q?1. In this work we develop a theory of coupled generic blocks with a certain randomness property to show that universality emerges essentially due to the interactions between elastic blocks, regardless of their microscopic nature. 相似文献
136.
Applied Mathematics and Mechanics - This study deals with the features of the mass and heat transport mechanism by adopting a modified version of Fourier and Fick’s model known as the... 相似文献
137.
Rehman Samiya Keefover-Ring Ken Haq Ihsan ul Dilshad Erum Khan Mohammad Imran Akhtar Nosheen Mirza Bushra 《Applied biochemistry and biotechnology》2019,188(3):893-895
Applied Biochemistry and Biotechnology - The original version of this article unfortunately contained a mistake in the image of Figure 1 and in Table 4. The corrected version of the figure... 相似文献
138.
Bernd Trathnigg Muhammad Imran Malik Nicole Pircher Stephan Hayden 《Journal of separation science》2010,33(14):2052-2059
In ternary mobile phases consisting of acetone, methanol, and water, the retention of PEG on reversed‐phase columns is independent on molar mass at certain compositions of the mobile phase. Along this critical adsorption line, the retention of polypropylene glycol varies quite strongly, which can be utilized in the separation of block copolymers. Gradient elution along the critical line allows a baseline separation of all oligomers in polypropylene glycol up to approximately 25 propylene oxide units. The same resolution can be achieved in the separation of ethylene oxide‐propylene oxide block copolymers, regardless of the length of the ethylene oxide block. 相似文献
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