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161.
K.T.A.L. Burm 《等离子体物理论文集》2013,53(3):202-205
Metal surfaces can be degreased via a combustion reaction upon the metal surface by the use of a plasma torch jet. The required energy and the reaction rate of the combustion reaction are examined here. It turns out that the reaction rate can limit the cleaning performance. In such case, the cleaning performance is not improved at higher powers. It is suggested to increase the temperature at which combustion takes place such that the cleaning performance can improve again at higher powers. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
162.
《Journal of polymer science. Part A, Polymer chemistry》2018,56(10):1039-1045
In this article, 10‐undecenoic acid, based on castor oil, was used a raw material for the synthesis of alternating copolymers. ω‐Unsaturated fatty esters as alkyl 10‐undecenoates were prepared by the esterification reaction of 10‐undecenoic acid with alkyl alcohol. A series of comb‐like copolymers were synthesized by free radical polymerization from maleic anhydride and alkyl 10‐undecenoates copolymers with different length of alkyl side chains in a toluene solution. These copolymers were investigated by 1H and 13C nuclear magnetic resonance, Fourier transform infrared spectroscopy, gel permeation chromatography, thermogravimetric analysis, differential scanning calorimetry (DSC). The copolymers were obtained in a low molecular weight in a range 3370–12,240 g mol−1 and their structural characterization indicated the formation of alternating copolymers. DSC characterization revealed that these comb‐like copolymers showed amorphous to semicrystalline behavior by increasing the length of side chains. The bio‐based comb‐like copolymers allow for the development of new polymeric materials for several applications. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 1039–1045 相似文献
163.
164.
《Comptes Rendus Chimie》2016,19(9):1113-1123
Lipids are an important and diverse group of naturally occurring organic compounds present in all biological entities. They play many essential roles in the survival of the organisms. Analysis of lipids is extremely complex due to their large variety of chemistries. In this work, we describe an innovative method for the characterization of the lipid composition in a complex and unknown vegetable oil: an extract of Kniphofia uvaria seeds; using Supercritical Fluid Chromatography (SFC) coupled to Atmospheric Pressure Chemical Ionization (APCI), High-Resolution Mass Spectrometry (HRMS) and UV detections. Thanks to the properties of supercritical CO2 allowing the use of a large number of chromatographic columns, an effective separation for this complex matrix was obtained. 相似文献
165.
Motoki Okaniwa Naoyuki Kawashima Michitaka Kaizu Yasuaki Mutsuga 《Journal of polymer science. Part A, Polymer chemistry》2013,51(15):3132-3143
A new polymer blend composed of a hydrogenated ring‐opening polymer (HROP) with an ester group and hydroxyl functionalized polystyrene (HFP) produced the excellent transparent materials which enabled a precise birefringence control in keeping with the other physical properties for optical film use. The blend with a composition from 0.28 to 0.35 for the HFP weight fraction showed an extraordinary wavelength dispersion, transmitting through a zero birefringence point at the critical fraction of 0.45, while each polymer showed an ordinary wavelength dispersion. The observed excellent transparency even above those of the glass transition temperature was attributed to a depressed phase separation that resulted from strong hydrogen bond between the ester and hydroxyl groups. An IR analysis of the film demonstrated a remarkable red‐shift in the carbonyl peak with an increase of the hydroxylated polystyrene content, indicating a strong hydrogen bond between those groups. This new polymer blend provides a useful design to achieve practical demands for film use, both optical and mechanical under the fabrication conditions using the melt extrusion technique. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3132–3143 相似文献
166.
Carbon black was modified using various liquid‐phase oxidation methods (modified carbon black = m‐CB, m = (1, 2, 3): 1, sulfuric acid/potassium permanganate method; 2, nitric acid method; 3, hydrogen peroxide method). With acetone–ethylene glycol as initiator, dimethyldiallylammonium chloride (DMDAAC) and acrylamide (AM) as monomer, cationic polyacrylamide (CPAM) was prepared by UV excitation of the monomer. The m‐CB/CPAM nanocomposites were synthesized using a hydrothermal method. The factors that affected the molecular weight of CPAM were investigated, including the total monomer concentration, the dosage of the complex initiator, the mass ratio of mAM:mDMDAAC and the UV irradiation time. The chemical structures and morphologies of the samples were characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental composition, X‐ray diffraction and scanning electron microscopy. 1‐CB/CPAM was utilized to flocculate oil sludge suspension, and the effects of 1‐CB quality, 1‐CB/CPAM dosage, temperature and pH value on the flocculation performance of 1‐CB/CPAM were investigated. The flocculation mechanism of 1‐CB/CPAM was also analyzed. The results show that 1‐CB/CPAM has an outstanding flocculation effect, and it flocculates oil sludge particles by adsorption bridging and charge neutralization in acidic and alkaline conditions. 相似文献
167.
Kubra Eksiler Yoshito Andou Hidayah Ariffin Yoshihito Shirai 《Journal of polymer science. Part A, Polymer chemistry》2019,57(24):2575-2580
This study addresses the inherent issues surrounding surface modification methods of nanofibers and proposes an environmentally friendly and less toxic strategy for the surface modification of hydrophilic nanofiber. From the continuation of our previous work, which discussed the easy production of nanofiber (average size: 127 nm) from oil palm mesocarp fiber (OPMF), in this work, the surface of nanofibers (M‐IL‐OPMF) were modified through vapor‐phase‐assisted surface polymerization (VASP) to improve the affinity of interface between the polymer grafted M‐IL‐OPMF and non‐polar matrix. VASP of ε‐caprolactone was successfully proceeded from the [M‐IL‐OPMF] at 70 °C for 24 h and 72 h, and compositions were estimated to be 35.7% fiber/64.3% polymer and 27.8% fiber/72.2% polymer. To confirm the grafting of PCL, size‐exclusion chromatography (SEC) and Fourier transform infrared (FT‐IR) spectroscopy, thermogravimetry (TG), and dispersibility test in hydrophobic solvent were carried out. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 2575–2580 相似文献
168.
Giinter Sorbe 《Journal of Dispersion Science and Technology》2013,34(3):287-302
Changes in composition of household washing detergents are reviewed, with emphasis on the importance of STPP As by law or voluntary agreement the STPP content in detergents has dropped during the last years in some countries, it will be shown that the quality of the used phosphates is of great influence on the quality of the final product In manufacturing detergents with low phosphate content it is important to use special STPP-types for every process The process technology of the manufacture of phosphate-containing powdered detergents can be divided into processes in which the individual components are worked up Into agglomeration products (spray mixing plants) and processes In which the individual components are combined to form a slurry of several substances (spray drying plants). 相似文献
169.
Li Wu Jian Li Jieshong Tu Wanzhen Gao Xinlei Gao 《Journal of Dispersion Science and Technology》2013,34(9):1297-1306
A W/O microemulsion reactor was used to prepare four kinds of modified lubricants: (i) modified lubricant 1, modified epoxidized microbial oil + rape oil in volume ratio of 1:1; (ii) modified lubricant 2, modified esterified microbial oil + rape oil in volume ratio of 1:3; (iii) modified lubricant 3, modified epoxidized rape oil; and (iv) modified lubricant 4, modified PAO. The individual modified lubricants were further modified with 0%, 0.5%, 1%, and 2% content of nano-Schiff base copper complex (nano-SBCC). A microtribometer was used to evaluate the friction coefficient between ball/flat point contacts immersed in the modified lubricants and operated in reciprocating and linear sliding mode. A comparison of the values of the friction coefficient with the lubricants further modified with nano-SBCC with those of their individual 0% nano-SBCC counterparts indicated significant decrease: (i) almost 19.18% was obtainable for the modified lubricant 1 with 2% of nano-Schiff base copper complex, (ii) almost 16.5% was obtainable for the modified lubricant 2 with 0.5% of nano-Schiff base copper complex; (iii) almost 7.42% was obtainable for the modified lubricant 3 with 1% of nano-SBCC; and (iv) almost 7.01% was obtainable for the modified lubricant 4 with 0.5% of nano-SBCC. These suggested that the addition of nano-Schiff base copper complex can efficiently decrease the friction coefficient of epoxidized or esterified microbial oil. Analyses of two-dimensional images, average profiles (across the mid-section y = 0 of the reciprocating sliding path), and three-dimensional topographies by confocal white light microscope for the worn surfaces of flats immersed in modified lubricant 1 and modified lubricant 2 suggested better wear-resistance of the modified lubricant 2 than that of the modified lubricant 1. The ability of wear resistance for the modified lubricant became better with the increasing content of nano-Schiff base copper complex from 0% to 2%. The study revealed the modification of epoxidized microbial oil + rape oil (1:1 volume ratio) and esterified microbial oil + rape oil (1:3 volume ratio) with Cu(II) chelate of bis(salicylaldehyde)ethylenediamine, reducing the magnitude of friction and wear because of their respective wear self-repairing ability. Such self-repairing ability furnishes the suitability of epoxidized microbial oil or esterified microbial oil to be effectively modified by nano-Schiff base copper complex and to substitute ordinary base oil as a mixture with rape oil. 相似文献
170.
Parham Dehghan Mina Noroozi Gity Mir Mohamad Sadeghi Mahbod Abrisham Arian Amirkiai Mahyar Panahi-Sarmad 《Journal of polymer science. Part A, Polymer chemistry》2020,58(21):3082-3094
The recent global pandemic and its tremendous effect on the price fluctuations of crude oil illustrates the side effects of petroleum dependency more evident than ever. Over the past decades, both academic and industrial communities spared endless efforts in order to replace petroleum-based materials with bio-derived resources. In the current study, a series of shape memory polymer composites (SMPC's) was synthesized from epoxidized vegetable oils, namely canola oil and castor oil fatty acids (COFA's) as a 100% bio-based polyol and isophorone diisocyanate (IPDI) as an isocyanate using a solvent/catalyst-free method in order to eventuate polyurethanes (PU's). Thereafter, graphene oxide (GO) nanoplatelets were synthesized and embedded in the neat PU in order to overcome the thermomechanical drawbacks of the neat matrix. The chemical structure of the synthesized components, as well as the dispersion and distribution levels of the nanoparticles, was characterized. In the following, thermal and mechanical properties as well as shape memory behavior of the specimens were comprehensively investigated. Likewise, the thermal conductivity was determined. This study proves that synthesized PU's based on vegetable oil polyols, including graphene nanoparticles, exhibit proper thermal and mechanical properties, which make them stand as a potential candidate to compete with traditional petroleum-based SMPC's. 相似文献