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厚膜型无溶剂环氧重防腐涂料的研究 总被引:8,自引:1,他引:7
比较了不同环氧树脂、环氧固化剂、颜填料、助剂等的特性,制备了厚膜型无溶剂环氧涂料,并进行了各项性能的检测,结果表明,该涂料具有极低的VOC含量,符合环保要求,适用于要求长效防腐的钢构件。 相似文献
3.
Xiaoqiang Li Jie Xu Lipeng Zhou Feng Wang Jin Gao Chen Chen Jianbo Ning Hong Ma 《Catalysis Letters》2006,110(1-2):149-154
Copper manganese oxides (Cu–Mn oxides) were prepared by coprecipitation method and characterized by several techniques, such
as X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and Temperature-programmed reduction (TPR).
Catalytic activities of the Cu–Mn oxides were tested by the oxidation of toluene with molecular oxygen in liquid phase and
solvent-free conditions. The molar ratio of Cu:Mn in catalyst was optimized to be 1:1 and thus the corresponding crystalline
material was designated as Cu1.5Mn1.5O4. 相似文献
4.
选择新型亲水扩链剂DMBA,采用无溶剂法合成抗起毛起球整理剂WPU,优化制备工艺,并将其应用在纯棉针织物和涤毛混纺针织物上。结果表明,针织物抗起毛起球等级提高了4级,织物手感和白度与原织物等级相当。红外光谱表征,异氰酸根已全部参与反应。扫描电镜(SEM)表明,经整理后的织物,纤维尾端被黏附在纱线的表面,织物表现出抗起毛起球的特征。 相似文献
5.
Sebastian Ronneberger Junfang Zhang Yuxin Liu Felix F. Loeffler 《Advanced functional materials》2023,33(17):2210116
Tagging, tracking, or validation of products are often facilitated by inkjet-printed optical information labels. However, this requires thorough substrate pretreatment, ink optimization, and often lacks in printing precision/resolution. Herein, a printing method based on laser-driven deposition of solid polymer ink that allows for printing on various substrates without pretreatment is demonstrated. Since the deposition process has a precision of <1 µm, it can introduce the concept of sub-positions with overlapping spots. This enables high-resolution fluorescent labels with comparable spot-to-spot distance of down to 15 µm (444,444 spots cm−2) and rapid machine learning-supported readout based on low-resolution fluorescence imaging. Furthermore, the defined thickness of the printed polymer ink spots can be used to fabricate multi-channel information labels. Additional information can be stored in different fluorescence channels or in a hidden topography channel of the label that is independent of the fluorescence. 相似文献
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采用水蒸气蒸馏法(HD)、微波辅助-水蒸气蒸馏法(MAHD)和微波无溶剂提取法(SFME)提取樟树落叶挥发油,用气相色谱-质谱及峰面积归一化法对挥发油成分进行分析鉴定.实验结果表明,3种方法提取的挥发油提取率接近,水蒸气蒸馏法为0.98%,微波辅助-水蒸气蒸馏法为1.12%,微波无溶剂提取法则为1.04%.3种方法提取的挥发油共鉴定出29种化合物,单萜类氧化物和倍半萜氧化物为挥发油的主要成分;HD所得挥发油中香樟醇、桉树叶醇、樟脑和α-松油醇的质量分数分别为25.58%、21.26%、16.79%和11.19%,MAHD为26.29%、28.72%、15.64%和10.16%,SFM为17.74%、17.74%、17.74%和12.46%.不同方法提取的樟树落叶挥发油提取率及成分总体相近,但也存在一定差异,这为进一步开发利用樟树落叶提供了一定的实验依据. 相似文献
8.
The preparation of thioethers by S-alkylation of various thiols with alkyl halides under solvent-free reaction conditions using potassium fluoride on alumina (KF/Al2O3) as a solid catalyst has been investigated in detail with respect to three different modes of reaction activation (ultrasound irradiation, microwave irradiation, and conventional heating) for obtaining maximum yield of the thioether. The importance of KF/Al2O3 as a particularly efficient catalyst was corroborated for all three modes of reaction activation, although the reaction time was found to be strongly dependent on the mode of activation. The yield of the thioethers was also found to depend on the amount of the solid catalyst relative to the equimolar amounts of the two reactants. 相似文献
9.
Hasnia Benmoussa Asma Farhat Rafik Bachoual Zina Nasfi Mehrez Romdhane 《分离科学与技术》2016,51(13):2145-2152
The present study aims to compare two innovative extraction techniques: microwave-assisted hydrodistillation (MAHD) and solvent-free microwave extraction (SFME) through traditional extraction techniques: hydrodistillation (HD) and steam distillation (SD) for their efficiency in the extraction of the volatile compounds from Tunisian Thymus vulgaris leaves; the kinetic, yield, composition and antibacterial activities of the essential oil were assessed in vitro. Results show that the essential oils extracted by microwaves were quantitatively (yield) similar to those obtained through the conventional methods, but qualitatively, essential oils analysed by gas chromatography–mass spectrometry (GC–MS) presented 17, 11, 11 and 8 compounds obtained through SFME, MAHD, SD and HD, respectively, mostly consisting of carvacrol (89.24–41.17%), followed by γ-terpinene (11.37–1.37%) and para-cymene (27.95–2.05%). The essential oils were screened for antibacterial activity against 5 microorganisms. All essential oils obtained by studied extraction methods showed the same resistance against Gram (?) and Gram (+) bacteria. The SFME method gave the best results: rapid kinetic of extraction (30 min vs. 35 min for MAHD, 120 min for SD, and 180 min for HD), less energy saving and cleanest process. 相似文献
10.
Polyvinylpolypyrrolidone-supported chlorosulfonic acid has been successfully applied to perform one-pot reaction of arylaldehydes, urea, ethylacetoacetate, or cyclic 1,3-diketo compounds under solvent-free condition at 70°C to provide a series of dihydropyrimidinones and octahydroquinazolin-2,5-diones in good to excellent yields. The method offers several advantages such as high yield, short reaction time, simple workup, easy preparation, and reusability of the catalyst. The [PVPP-SO3H]+Cl? catalyst was characterized via Fourier transform infrared spectroscopy (FT-IR) and thermal gravimetric analysis (TGA). Moreover, the catalyst could be recycled several times without significant loss of its catalytic activity. Clean methodologies, easy work-up procedure, high yield, and simple preparation of the catalyst are some advantages of this article. 相似文献