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31.
Winges FATIMA Muhammad TARIQUE LI Min CHEN Mingyi Muzamil KHATRI Muhammad Nauman SARWAR Icksoo KIM Farooq AHMED Zeeshan KHATRI CHEN Rouxi WEI Kai 《高等学校化学研究》2021,37(3):535-540
Based on the functional properties of electrospun cellulose nanofibers(CNF), scientists are showing substantial interest to enhance the aesthetic properties. However, the lower color yield has remained a big challenge due to the higher surface area of nanofibers. In this study, we attempted to improve the color yield properties of CNF by the pad-steam dyeing method. Neat CNF was obtained by deacetylation of electrospun cellulose acetate(CA) nanofibers. Three different kinds of reactive dyes were used and pad-steam dyeing parameters were optimized. SEM images revealed smooth morphology with an increase in the average diameter of nanofibers. FTIR results showed no change in the chemical structure after dyeing of CNF. Color fastness results demonstrated excellent ratings for reactive dyes, which indicate good dye fixation properties and no color loss during the washing process. The results confirm that the pad-steam dyeing method can be potentially considered to improve the aesthetic properties of CNF, which can be utilized for functional garments, such as breathable raincoats and disposable face masks. 相似文献
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Preparation of Novel Side-chain Pseudopolyrotaxanes Consisting of Cucurbituril[6] and Polyamine Salts 总被引:1,自引:0,他引:1
Zhao Sheng HOU Ye Bang TAN Kimoon KIM Qi Feng ZHOU 《中国化学快报》2005,16(8):1031-1034
Pseudorotaxane monomer (VBCB) containing cucurbitutil[6] (CB[6]) and N^1-(4-vinylbenzyl)-1,4-diaminobutane dihydrochloride (VBDADC) is obtained by self-assembly of cucurbituril[6] with VBDADC in water and then polymerized using potassium persulfate (KPS) as initiator to give novel water-soluble side-chain cucurbituril[6]-based pseudopolyrotaxane(PVBCB). The chemical structures of PVBCB, VBCB and VBDADC are confirmed by ^1H NMR,^13C NMR spectra and elemental analysis. In VBCB, CB[6] is localized aliphatic group of the side chain and the molar ratio of CB[6] to VBDAC is 1:1 . 相似文献
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The unsteady natural convective couple stress fluid flow over a semi-infinite vertical cylinder is analyzed for the homogeneous first-order chemical reaction effect. The couple stress fluid flow model ... 相似文献
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Instability Parameters of Optical Oscillation Frequency in Plasma Central Discharge and Periphery Region
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We have observed relaxation oscillations in a capacitive discharge in Ar gas, connected to a peripheral ground chamber. The plasma oscillations observed from time-varying optical emission from the main discharge chamber show, for example, a high frequency (75.37kHz) relaxation oscillation, at lOOmTorr and 8 W absorbed power, and a low frequency (2.72Hz) relaxation oscillation, lOO mTorr and 325 W absorbed power. Time-varying optical emission intensity and plasma density are also detected with a Langmuir probe. The theoretical result agrees well with experiments. 相似文献
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JIN Yin-zhe LI Guang-hua AHN So-young ROW Kyung-ho KIM Eun-ki 《高等学校化学研究》2006,22(2):162-167
Introduction Melaninisaheterogeneousbiopolymerproduced bytheskincells,melanocytes,whichdetermine,mostly,thecoloroftheskin.Excessiveproductionof melaninanditsaccumulationintheskincancausepig mentingdisordersincludingmelasma,solarlentigoand postinflammatory… 相似文献
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SangDongKIM ByeongChunSHIN 《计算数学(英文版)》2003,21(2):113-124
The bounds for the eigenvalues of the stiffness matrices in the finite element discretiza-tion corresponding to Lu:=-u″with zero boundary conditions by quadratic hierarchical basic are shown explicitly.The condition numberof the resulting system behaves like O(1/h)where h is the mesh size.We also analyze a main diagonal preconditioner of the stiffness matrix which reduces the condition number of the preconditioned system to O(1). 相似文献
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The sol-gel derived glucose biosensor was developed, and the sol-gel membrane was organically modified by N-(3-triethoxysilylpropyl)-ferrocenylmethylamine (FcSi) as sol-gel precursor to make electrochemical biosensor. The structure of biosensor was sol-gel/FcSi+GOx/GC type (glucose oxidase, GOx). The ferrocene mediator was chemically immobilized to the silane network, and GOx was entrapped to the sol-gel glass network. Therefore, these structures prevented mediator leakage and retained the enzyme activity. Additionally, pH of electrolyte, temperature effects, and interference of positive substances with biosensor were investigated. And the electrochemical performance of biosensor was studied by amperometry. The results indicated that the linear range, detection limit. and response slope of biosensor was 2.00×10^-4-1.57×10^-3 mol·L^-1, 2.0×10^-4 mol·L^-1 and 5.06×10^5 nA·mol^- 1·L, respectively. 相似文献
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