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排序方式: 共有1923条查询结果,搜索用时 265 毫秒
51.
采用浅层地震勘探技术在矿区第四纪松散地层进行地层、构造和地下水勘探。通过以反射波法为主,折射波、面波法为辅的综合地震勘探方法较为准确地对勘探区地层进行了划分,结合钻孔勘探,有效揭露了矿区第四系地层厚度及地层空间展布特征。地震勘探将矿区地层划分为三大套岩性层,分别为第四系全新统地层、上更新统地层和元古界基岩层,与钻孔勘探揭露地层基本一致。钻孔K1处地震法解释第四纪地层厚度为240m,钻孔勘探揭露厚度为241.37m,验证了地震勘探的可靠性。 相似文献
52.
烷基季铵盐改性膨润土的膨胀性 总被引:2,自引:0,他引:2
用X射线衍射(XRD)、傅立叶红外光谱(FT-IR)和热重(TG)表征方法,考察了四甲基溴化铵(TMAB),四乙基溴化铵((Et)4NB),十二烷基三甲基溴化铵(DTAB),十六烷基三甲基溴化铵(CTAB)对膨润土膨胀性的影响。结果表明,不同季铵盐都已吸附到膨润土晶层间,短链季铵盐TMAB和(Et)4NB主要以单分子平躺在膨润土晶层之间,使膨润土的层间距比原土样降低,有很好的防膨作用。长链季铵盐DTAB和CTAB以假三层平卧、倾斜排列等方式排列,使膨润土的层间距比原土样增加,没有防膨作用。且膨润土对(Et)4NB和TMAB的吸附量低于DTAB和CTAB的。 相似文献
53.
以火法冶金炼制的粗铬金属作为阳极进行电解,通过选择性的阳极溶解及阴极沉积,达到分离杂质和提纯金属的目的,选用NaBr-KBr-尿素+Cr2(SO4)3(无水)作低温熔盐体系进行铬的电精炼,温度为65-108℃,以2.27~22.7A/dm^2电流密度进行电解,研究了电流密度和温度对金属铬电精练的阴极电流效率的影响,实验表明,在该体系中电精炼过程无析氢发生;较低的温度和适中的电流密度有利于金属铬的电精炼,通过实验确立了电精炼铬合适的电解温度为85℃,电流密度为9.09A/dm^2。 相似文献
54.
Elif Aykın Sultan Arslan Atike N. Durak 《International Journal of Food Properties》2016,19(1):222-232
In this research, the effect of different bicarbonate salts (sodium and ammonium) and their doses (0, 1, 2, and 3 g/100 g raw material) in the coating batter formula use and the sequential use of frying oil (1st, 2nd, 3rd, and 4th) on 5-hydroxymethylfurfural and acrylamide contents in coated fried chicken meat. The addition of sodium bicarbonate was efficient for reducing acrylamide content, but it increased browning and 5-hydroxymethylfurfural content compared to the control. When increasing the doses of sodium and ammonium bicarbonate from 1 to 3 g/100 g of raw material, the acrylamide content of samples did not change significantly, although adding sodium bicarbonate significantly reduced the acrylamide content as a control. These research results showed that using about 1 g/100 g raw material sodium bicarbonate rather than ammonium bicarbonate and as little frying oil as possible use during the production of coated and fried meat results in lower contents of 5-hydroxymethylfurfural and acrylamide. 相似文献
55.
Ligang Zhao Yan Li Changshun Ren Yongnan Xu Zhonggui He 《Drug development and industrial pharmacy》2013,39(7):814-826
Purpose: To enhance the transdermal delivery of diclofenac acid (DA) by using O-acylmenthol as a penetration enhancer and complexing with amines, or by a combination of the two methods. Methods: The skin permeability of diclofenac was tested in vitro across rat skin with each of the evaluated permeants in a saturated isopropyl myristate (IPM) donor solution. Results: A 4.5-fold increase in the flux of diclofenac was observed by ion-pair formation with diethylamine; however, the cations with hydroxyl groups had negative effects on the transdermal delivery of diclofenac. 2-isopropyl-5-methylcyclohexyl 2-hydroxypanoate and 2-isopropyl-5-methylcyclohexyl heptanoate produced significant increase in the permeation of diclofenac potassium (D-K); however, both of them were ineffective for the other diclofenac salts, including diclofenac diethylamine (D-DETA), diclofenac ethanolamine (D-EA), diclofenac diethanolamine (D-DEA), diclofenac triethanolamine, and diclofenac N-(hydroxylethyl) piperidine. 2-isopropyl-5-methylcyclohexyl tetradecanoate was effective on the penetration of D-K, D-DETA, D-EA, and D-DEA. Also, it is exciting to note that the combined use of diethylamine with 2-isopropyl-5-methylcyclohexyl tetradecanoate produced a 9.74-fold increase in accumulation amount of diclofenac compared with DA in IPM. Conclusions: The use of ion pair in combination with O-acylmenthol is necessary to further increase the diclofenac flux to provide better compliance for the patients undergoing clinical therapy. 相似文献
56.
Improvement of corrosion protection offered to galvanized steel by incorporation of lanthanide modified nanoclays in silane layer 总被引:1,自引:0,他引:1
C. Motte M. Poelman A. Roobroeck M. Fedel F. Deflorian M.-G. Olivier 《Progress in Organic Coatings》2012
Silane sol–gel based films are very promising alternatives to the traditional chromate pre-treatments. However, the protection offered by the silane films strongly decreases when the coating is damaged. Some previous studies showed that the barrier properties of the silane layer can be improved by incorporation of clay nanoparticles. Moreover, inhibitive metallic cations can be incorporated in the nanoclays by ion exchange, providing a way to prepare cheap corrosion inhibitors nanoreservoirs offering self-healing properties. Rare earth (RE) metal salts have been shown to be effective corrosion inhibitors on a wide range of metals, including hot dip galvanized (HDG) steel. For this study, montmorillonite clay is modified to obtain a Ce(III) montmorillonite clay (Ce-MMT). The amount of incorporated Ce(III) is characterized by means of XRF measurements. X-ray diffraction showed that the Ce(III) is located in the interlayer space. 相似文献
57.
Fernanda Batistel Jonas de Souza Flávio Augusto Portela Santos 《Journal of dairy science》2017,100(7):5343-5357
The objective of our study was to investigate the associative effects of feeding Ca salts of palm fatty acids (FA) and corn grain-processing method on production, nutrient digestibility, energy balance, and carryover effects of early-lactation dairy cows grazing a tropical pasture. Treatment diets were offered from 3 to 16 wk postpartum (treatment period), in which all cows grazed elephant grass (Pennisetum purpureum L. Cameroon) and treatments were added to a concentrate supplement. Treatments were flint corn grain-processing method either as fine ground (FGC) or steam-flaked (SFC) associated with Ca salts of palm FA supplementation either not supplemented or supplemented (CSPO). From 17 to 40 wk postpartum (carryover period) all cows received a common diet fed as total mixed ration. During the treatment period, a tendency for an interaction between CSPO and corn grain-processing method were observed for milk yield, milk fat yield, and energy-corrected milk (ECM), as CSPO caused them to increased to a greater extent in the FGC diet compared with the SFC diet. Furthermore, a tendency for an interaction between CSPO and corn grain-processing method was observed for body weight change, because CSPO increased body weight loss in the FGC diet but not in the SFC diet. The CSPO increased milk yield, milk fat yield, 3.5% fat-corrected milk, ECM, and cumulative milk yield compared with not supplemented. Also, CSPO increased energy intake, milk energy output, and energy partitioning toward milk, whereas reduced energy was allocated to body reserves. The SFC increased milk yield, ECM, milk protein yield, milk casein yield, and cumulative milk yield, and decreased milk urea N compared with FGC. The SFC compared with FGC also increased body condition score and body weight change, and increased energy partitioning toward body reserves. During the carryover period, an interaction between CSPO and corn grain-processing method was observed for milk yield, which occurred because CSPO maintained higher milk yield in the FGC diet but not in the SFC diet. Therefore, in the carryover period, the additive effect between SFC and CSPO that occurred in the treatment period was not maintained throughout the carryover period. However, CSPO increased yields of milk fat, protein, casein as well as fat-corrected milk and ECM. In conclusion, corn grain-processing method interacts with CSPO supplementation on production responses and carryover effects of grazing cows. When CSPO was fed in the FGC diet, milk production increased to a greater extent than when fed in the SFC diet, but also caused greater mobilization of reserves at early lactation. This suggests an interaction between fat supplementation and corn grain-processing method on energy partitioning of dairy cows. Also, both supplementation with CSPO and SFC were effective strategies to increase energy intake and yields of milk and milk solids. The carryover effect on milk production was greater for CSPO supplementation than corn grain-processing method, whereas feeding SFC diets had lower mobilization of reserves and less body weight and body condition score variation throughout lactation. 相似文献
58.
Ligang Xu Yaji Huang Jian Wang Changqi Liu Lingqin Liu Lei Zou Junfeng Yue Kuixu Chen 《加拿大化工杂志》2020,98(4):905-918
The presence of reducing atmospheres of the waterwall fireside in the boiler due to extensive use of low-NOx combustion mode caused severe high-temperature corrosion problems. In this study, high-temperature sulphur corrosion properties of two types of low alloyed waterwall steel (15CrMoG and 12Cr1MoVG) in two kinds of reducing-sulphidizing atmospheres were investigated by lab-scale experiments. The experimental atmospheres and temperature were simulated according to field measurements in the boiler of a thermal power plant. The experimental results showed that the reducing-sulphidizing atmosphere with CO was more corrosive, and the CO accelerated the corrosion of H2S and worsened the corrosion. The CO inhibited the formation of oxide scales, provided some corrosion resistance, and produced the intensely corrosive COS. The corrosivity of the alkali metal chlorides was limited in the reducing-sulphidizing atmosphere without CO, while the corrosion was strongly hindered in the reducing-sulphidizing atmosphere with CO. 相似文献
59.
60.
Ana Paula Pereira Ana Mendes‐Ferreira Leticia M. Estevinho Arlete Mendes‐Faia 《Journal of the Institute of Brewing》2015,121(3):405-410
Through honey's fermentation, diverse beverages can be obtained, among which is mead, an alcoholic drink with 8 to 18% of ethanol (v/v). Since honey is a matrix with a low nutrient concentration and other unfavourable growth conditions, several problems are usually encountered, namely delayed or arrested fermentations, unsatisfactory quality parameters and lack of uniformity of the final product, as well as unpleasant sensory properties. In this context, the aim of this work was to optimize mead production through honey‐must supplementation with (a) salts, (b) vitamins or (c) salts + vitamins. The effects of the honey‐must formulation on the fermentation kinetics, growth profile and physicochemical characteristics of final meads were evaluated. The results showed minor differences in the fermentation profile and time between fermentations with the different formulations. The growth profile was influenced more by the yeast strain than by the supplements added to the honey‐must. In general, the honey‐must composition did not influence meads’ final characteristics, except regarding the SO2 concentration of the meads produced using the strain QA23. In summary, the addition of salts and/or vitamins to honey‐must had no positive effects on the fermentation, growth profile or characteristics of the final products. Copyright © 2015 The Institute of Brewing & Distilling 相似文献