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1.
阐述了丙烯酸树脂的发展历程和研究现状。按照成膜方式、分散所用溶剂和树脂用途对丙烯酸树脂进行分类。详细介绍了丙烯酸树脂在海洋防污涂料中的应用,其中包括无锡自抛光丙烯酸锌/铜树脂涂料、有机硅改性丙烯酸树脂防污涂料和有机氟改性丙烯酸树脂防污涂料。最后对丙烯酸树脂研究方向进行了展望。  相似文献   

2.
针对高塔分离法只能对定比例阴阳树脂进行分离、输送的问题,提出通过改变阴阳树脂的输出顺序,重新设置视镜和阴树脂出口位置,使分离塔可以对不同阴阳树脂配比的混合失效树脂进行分离、传输。对树脂输送过程转移流量的控制与匹配进行了分析,并结合实验给出了最佳选择。  相似文献   

3.
亢新梅  张教强  张莹  姚莹莹 《粘接》2010,31(7):57-61
双马来酰亚胺树脂/氰酸酯树脂(BT树脂)是一种高性能热固性树脂,综合了氰酸酯树脂与双马来酰亚胺树脂的优良性能,应用领域广泛。阐述了BT树脂的固化机理及现有的改性研究思路。并且对我国BT树脂的发展进行了展望。  相似文献   

4.
研究了氯醋树脂的改性,并对改性树脂性能进行了表征。氯醋树脂通过碱法催化方式在甲醇溶液中改性,制备了含羟基的三元树脂,羟值为63~76。对得到的含羟基三元树脂用甲苯—2,4-异氰酸酯进行改性,改性后得到的聚氨酯树脂比三元树脂材料的力学性能有较大的提高,最大载荷提高了50%,抗拉强度提高了100%,储能模量提高了60%;通过红外光谱,表明有—NH存在,羟基特征峰消失,即表明,对三元树脂中羟基进行了屏蔽。这些改性树脂具有较好的应用前景。  相似文献   

5.
光固化树脂的制备及应用   总被引:4,自引:0,他引:4  
确定了光固化树脂预聚体的合成条件,制备了激光快速成型用光固化树脂,并对该树脂进行了性能评价和对其应用前景进行了阐述。  相似文献   

6.
乙烯基酯树脂性能及应用   总被引:2,自引:1,他引:1  
本文对环氧树脂与丙烯酸为原料合成的乙烯基酯树脂的品种、性能及应用进行了阐述,并对乙烯基酯树脂与其它树脂的性能进行了比较。  相似文献   

7.
介绍了近几年有机硅对树脂进行化学改性的技术及其研究情况。指出目前有机硅改性树脂的研究重点,并对有机硅改性树脂的发展方向进行了展望。  相似文献   

8.
采用自制的分散树脂对二氧化钛进行分散,将制备的色浆应用于含氟丙烯酸酯树脂、三氟氯乙烯和四氟乙烯氟碳树脂等耐候性含氟树脂涂料中,考察了分散树脂对含氟树脂涂层耐QUV老化性能的影响。  相似文献   

9.
综述了国内外近年来通过采用刚性粒子、橡胶弹性体、热塑性树脂、形成半互穿聚合物网络及液晶聚合物等手段对热固性树脂进行增韧改性的研究进展。重点对橡胶弹性体和热塑性树脂增韧改性热固性树脂的影响因素进行了分析,指出了目前热固性树脂增韧改性技术存在的问题及发展趋势。  相似文献   

10.
马平  田莉莉 《广东化工》2011,38(11):209-210
以聚苯乙烯类树脂为原料,采用Blanc氯甲基化的方法对交联聚苯乙烯类树脂进行氯甲基化,并对氯含量进行了测定筛选出产率高的树脂,对氯甲基化方法进行筛选。  相似文献   

11.
The mineralogy of coal and coal ash samples from a wide variety of deposits worldwide has been studied by X-ray diffractometry, light microscopy, SEM, TEM, and DTA-TGA methods. The common major minerals identified in the crystalline matter of coals are quartz, kaolinite, illite, calcite, pyrite, plagioclase, K-feldspar and gypsum, and occasionally dolomite, ankerite, siderite, Fe oxyhydroxides and sulphates. A number of minor and especially accessory minerals are also present. The modes of occurrence and some genetic peculiarities of the minerals found are described and summarized. Minerals and phases of probable detrital origin include mainly silicates, volcanic glass, oxyhydroxides and phosphates. Authigenic minerals of syngenetic origin may be sulphides, clay minerals, carbonates and rarely sulphates and phosphates. Epigenetic minerals, formed by the infiltration of low-temperature hydrothermal solutions, may include sulphides, carbonates, sulphates, clay minerals, quartz, chlorides, and probably alkaline-earth hydroxides and zeolites. The alteration products of detrital and authigenic minerals may be Fe and Al oxyhydroxides, sulphates, kaolinite, illite, chlorite, muscovite, zeolites and calcite. The behaviour of these minerals and phases during low- and high-temperature ashing is also discussed.  相似文献   

12.
几种杀虫剂对草坪害虫的控制效果   总被引:6,自引:0,他引:6  
李有志  马骏  黄继光  徐汉虹  文礼章 《农药》2006,45(8):561-564
测定了绿僵菌、毒死蜱、辛硫磷等药剂对草坪害虫的控制效果。结果表明绿僵菌、毒死蜱和辛硫磷都是防治草坪地下害虫的有效药剂,毒死蜱和辛硫磷还能有效防治草坪茎叶害虫禾灰翅夜蛾和斜纹夜蛾等。药后45d,绿僵菌对铜绿丽金龟幼虫蛴螬的防效和对地下害虫的总防效分别为91.2%和87.6%。绿僵菌对茎叶害虫的防效较差,药后3、7、10d时,对禾灰翅夜蛾的防效分别为3.7%、9.2%和18.9%;对茎叶害虫的总防效在12.2%以下。辛硫磷和毒死蜱药后3d对禾灰翅夜蛾的防效分别是93.7%和97.6%;对茎叶害虫的总防效分别是92.0%和93.6%。当高效氯氰菊酯分别和辛硫磷、毒死蜱混用防治斜纹夜蛾时,防效更高、速效性更好。  相似文献   

13.
Shifeng Dai  Dexin Han 《Fuel》2006,85(4):456-464
Coals from Luquan, Yunnan Province, China, have high contents of cutinite and microsporinite, with an average of 55 and 33.5 vol%, respectively, (on a mineral-free basis). The coals are classified as cutinitic liptobiolith, sporinite-rich durain, cutinite-rich durain, and sporinitic liptobiolith. These four liptinite-rich coals are often interlayered within the coal bed section and vary transversely within the coal bed. The vitrinite content varies from as low as 1.6-20.5% (mineral-free basis), and it is dominated by collodetrinite, collotelinite, and corpogelinite. The maceral composition may be attributed to the type of the peat-forming plant communities. Moreover, the Luquan coals are characterized by high contents of volatile matter, hydrogen, and oxygen, and the high values of the atomic hydrogen to carbon ratio as a result of the maceral composition. As compared with the common Chinese coals and the upper continental crust, the Luquan coals are enriched in Li, B, Cu, Ga, Se, Rb, Mo, Ba, Pb, Bi, and U, with averages of 99.9, 250, 111, 24.4, 4.55, 130, 58.8, 1276, 162, 3.85, and 34.1 μg/g, respectively. The SEM-EDX results show that V, Cr, Ga, and Rb occur mainly in clay minerals, and Cu and Pb are associated with clay minerals and pyrite, and Mo and U are mainly in clay minerals and organic matter. Barite and clay minerals are the main carrier of barium. The high B and U contents are probably resulted from deep seawater influence during coal formation.  相似文献   

14.
介绍近年来我国橡胶防老剂和促进剂进出口情况。2013年,我国防老剂和促进剂进口量分别为19046.61 t和14984.44 t,同比分别增长16.12%和11.64%;进口金额分别为6202.02万美元和7391.97万美元,同比分别增长14.76%和1.39%;出口量分别为29070.40 t和89942.59 t,同比分别增长62.68%和45.72%;出口金额分别为6794.43万美元和27885.34万美元,同比分别增长60.45%和50.17%。我国进口防老剂主要来自中国大陆(以国货复进口形式进口)、美国、韩国以及中国台湾省等,进口促进剂主要来自中国台湾省、美国、韩国、日本以及德国等,防老剂主要出口日本、泰国、印度尼西亚和韩国等,促进剂主要出口美国、韩国、巴西、泰国和日本等。  相似文献   

15.
The scientific community and industrial companies have discovered significant enzyme applications to plant material. This rise imparts to changing consumers’ demands while searching for ‘clean label’ food products, boosting the immune system, uprising resistance to bacterial and fungal diseases, and climate change challenges. First, enzymes were used for enhancing production yield with mild and not hazardous applications. However, enzyme specificity, activity, plant origin and characteristics, ratio, and extraction conditions differ depending on the goal. As a result, researchers have gained interest in enzymes’ ability to cleave specific bonds of macroelements and release bioactive compounds by enhancing value and creating novel derivatives in plant extracts. The extract is enriched with reducing sugars, phenolic content, and peptides by disrupting lignocellulose and releasing compounds from the cell wall and cytosolic. Nonetheless, depolymerizing carbohydrates and using specific enzymes form and release various saccharides lengths. The latest studies show that oligosaccharides released and formed by enzymes have a high potential to be slowly digestible starches (SDS) and possibly be labeled as prebiotics. Additionally, they excel in new technological, organoleptic, and physicochemical properties. Released novel derivatives and phenolic compounds have a significant role in human and animal health and gut-microbiota interactions, affecting many metabolic pathways. The latest studies have contributed to enzyme-modified extracts and products used for functional, fermented products development and sustainable processes: in particular, nanocellulose, nanocrystals, nanoparticles green synthesis with drug delivery, wound healing, and antimicrobial properties. Even so, enzymes’ incorporation into processes has limitations and is regulated by national and international levels.  相似文献   

16.
Abiotic stresses, such as drought, salinity, heat, cold, and heavy metals, are associated with global climate change and hamper plant growth and development, affecting crop yields and quality. However, the negative effects of abiotic stresses can be mitigated through exogenous treatments using small biomolecules. For example, the foliar application of melatonin provides the following: it protects the photosynthetic apparatus; it increases the antioxidant defenses, osmoprotectant, and soluble sugar levels; it prevents tissue damage and reduces electrolyte leakage; it improves reactive oxygen species (ROS) scavenging; and it increases biomass, maintains the redox and ion homeostasis, and improves gaseous exchange. Glutathione spray upregulates the glyoxalase system, reduces methylglyoxal (MG) toxicity and oxidative stress, decreases hydrogen peroxide and malondialdehyde accumulation, improves the defense mechanisms, tissue repairs, and nitrogen fixation, and upregulates the phytochelatins. The exogenous application of proline enhances growth and other physiological characteristics, upregulates osmoprotection, protects the integrity of the plasma lemma, reduces lipid peroxidation, increases photosynthetic pigments, phenolic acids, flavonoids, and amino acids, and enhances stress tolerance, carbon fixation, and leaf nitrogen content. The foliar application of glycine betaine improves growth, upregulates osmoprotection and osmoregulation, increases relative water content, net photosynthetic rate, and catalase activity, decreases photorespiration, ion leakage, and lipid peroxidation, protects the oxygen-evolving complex, and prevents chlorosis. Chemical priming has various important advantages over transgenic technology as it is typically more affordable for farmers and safe for plants, people, and animals, while being considered environmentally acceptable. Chemical priming helps to improve the quality and quantity of the yield. This review summarizes and discusses how exogenous melatonin, glutathione, proline, and glycine betaine can help crops combat abiotic stresses.  相似文献   

17.
松香是一类产量丰富、价格低廉的可再生林产资源,被广泛地应用于食品、农业、橡胶、油墨、涂料等领域。松香的三环二萜结构具有超强的疏水性,通过催化异构、Diels-Alder加成等手段引入亲水基团可制备高附加值、易生物降解的绿色表面活性剂。本文从阴离子、阳离子、非离子和两性离子表面活性剂4个大类对松香基表面活性剂应用的文献及专利进行综述,重点分析了羧酸盐、磺酸盐、硫酸盐和磷酸盐4种阴离子型表面活性剂和季铵盐阳离子型表面活性剂,多元醇型和聚氧乙烯型非离子表面活性剂,以及甜菜碱型和氧化胺型两性离子表面活性剂。剖析松香基表面活性剂产业化开发的新技术及新产品概况,提出松香基表面活性剂替代传统表面活性剂的潜在应用领域。同时,对松香基表面活性剂的研究发展与产业化发展进行了评价与展望。  相似文献   

18.
The susceptibility and the severity of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are associated with hyperandrogenism, obesity, and preexisting pulmonary, metabolic, renal, and cardiac conditions. Polycystic ovary syndrome (PCOS), the most common endocrine disorder in premenopausal women, is associated with obesity, hyperandrogenism, and cardiometabolic dysregulations. We analyzed cardiac, renal, circulatory, and urinary SARS-CoV-2 viral entry proteins (ACE2, TMPRSS2, TMPRSS4, furin, cathepsin L, and ADAM17) and androgen receptor (AR) expression, in a peripubertal androgen exposure model of PCOS. Peripubertal female mice were treated with dihydrotestosterone (DHT) and low (LFD) or high (HFD) fat diet for 90 days. HFD exacerbated DHT-induced increase in body weight, fat mass, and cardiac and renal hypertrophy. In the heart, DHT upregulated AR protein in both LFD and HFD, ACE2 in HFD, and ADAM17 in LFD. In the kidney, AR protein expression was upregulated by both DHT and HFD. Moreover, ACE2 and ADAM17 were upregulated by DHT in both diets. Renal TMPRSS2, furin, and cathepsin L were upregulated by DHT and differentially modulated by the diet. DHT upregulated urinary ACE2 in both diets, while neither treatment modified serum ACE2. Renal AR mRNA expression positively correlated with Ace2, Tmprss2, furin, cathepsin L, and ADAM17. Our findings suggest that women with PCOS could be a population with a high risk of COVID-19-associated cardiac and renal complications. Furthermore, our study suggests that weight loss by lifestyle modifications (i.e., diet) could potentially mitigate COVID-19-associated deleterious cardiorenal outcomes in women with PCOS.  相似文献   

19.
韦朝海  廖建波  胡芸 《化工进展》2016,35(6):1875-1883
通过回顾性叙述煤干馏、煤制焦、煤制气、煤制油等方面的煤化工过程基本原理,分析了煤化工过程的产品方向,从煤的性质、工艺要求和技术特点介绍了煤化工过程产生污染物的原因。从煤制焦、煤制气两个方面重点分析了“三废”的来源及其成分,其中,废气来自化学转化过程中未完全炭化的细煤粉及其析出的挥发分、焦油气、飞灰和泄漏的粗煤气、出焦时灼热的焦炭与空气接触生成的CO、CO2、NO2等,废水包括除尘废水、剩余氨水、酚氰废水、脱硫废液、煤气水封水等,废渣包括粉尘、煤尘、酸焦油、焦油渣、剩余污泥等。煤化工过程的气相污染物主要包括碳氧化物、硫氧化物、氨气、挥发酚、苯、苯并芘、CO、CH4、小分子烃类化合物等,液相污染物除了含有氨氮、氰化物、硫氰化物、硫化物、苯类、酚类及油分外,还含有大量苯并芘、萘等的多环芳烃和吡啶、咔唑、联苯、三联苯等的杂环芳烃化合物。煤化工污染表现为分布面广、组分复杂、高浓度、多相介质共存、环境风险大的特征,而煤化工废水则表现为高浓度/盐分、高污染(组分多)、有毒难降解、富氮缺磷的典型特征。文中指出煤化工过程与污染特征之间的关系的阐明需要科技工作者加深对煤的基本性质、转化过程原理、分离纯化原理、产品应用原理的全面认识,与此对应的技术与策略应当立足于对行业的资源-产品-经济-环境-社会作用链深度理解和有效的系统集成基础上,从规模、产品、技术、管理、市场、人才等方面加强战略设计与逻辑创新的构建。  相似文献   

20.
根据市场需求研究制定了林业行业标准《日用樟脑》。该标准主要规定了日用樟脑的外观、性状、嗅味感、要求、试验方法、功能添加剂、形状、大小、包装、标识、贮存、运输、卫生和管理,适用于以合成樟脑或者天然樟脑为基本原料制得的各种不同形状的日用樟脑制品。研究建立了以气相色谱分析为主的相应检测和分析试验方法,确定了含量、密度等主要技术参数及取值范围。同时还研究了日用樟脑中相关掺假制假物质的分析检验方法。  相似文献   

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