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161.
Ionic fluids are liquid salts that have been investigated for a number of applications, including catalysis, their use as solvents and electrically conducting fluids. Chemically, they consist of ionically bonded species, and depending on the cation and anion, can be extremely valuable in the chemical processing industry. Another characteristic that makes them useful is a high viscosity and good lubrication properties. This paper examines a number of ionic fluids, and determines their suitability as lubricants. This involves determining rheological properties, including viscosity and high-pressure viscosity, generally using a Barus law. In addition, their traction behavior is measured to evaluate their lubricating properties. Since metalworking fluids (and lubricants in general) are used in non-isothermal situations, the thermal conductivity of these fluids have also been measured. 相似文献
162.
综述了岛礁混凝土结构表面防护涂料海洋环境适应性评价(老化)研究进展,对表面防护涂料海洋环境适应性评价中试验设计、控制因子设定、试验方法选择、评价指标确定等环节中存在的问题进行了讨论,认为只有在认真梳理单环境因子对涂料作用机理的基础上,对它们进行合理设定,才能有效提高加速试验结果和自然暴晒老化试验结果的相关性。 相似文献
163.
In this study, a new and facile route was employed for synthesis of polyamidine with abundant cations and attractive five-membered ringlike structural unit. N-vinylformamide and acrylonitrile copolymerized firstly to form intermediates, and the intermediates were processed with hydrochloric acid to produce polyamidine. A series of polymerization conditions (e.g. polymerization time, temperature and dosage of initiator) were optimized through productivity, viscosity and cationic degree as evaluation. SEM analysis illustrated that the amidinization process could reduce the size of spaces between molecular and created compact structure, which would contribute to good flocculation performance and high viscosity. FT-IR, XPS and NMR spectra presented a rather clear structure of polyamidine. 34.3% of sludge was sedimentated through the flocculation of polyamidine in the early stages. In contrast, only 6.8% of sludge was sedimentated by polyacrylamide. The moisture content in dehydrated floc could be reduced to 77.7% when 60 mg/L polyamidine was added. These results demonstrated that the polyamidine showed a great potential in the practical application of sludge dewatering. 相似文献
164.
以喀斯特不同坡位的圆果化香为研究对象,测定上坡和中坡的土壤理化性质、圆果化香叶片的生理生化以及形态指标,研究不同坡位下圆果化香种群的水分调控、光合能力和形态特征的适应性差异。结果表明:(1)土壤含水量中坡比上坡高出94.73%,土壤有机质含量高出81.96%;土壤有效磷含量中坡高于上坡,全氮和全钾含量在两个坡位相差不大。(2)叶片净光合速率(Pn)日变化在上午9:00~11:00和下午13:00~16:00时中坡高于上坡,在"光合午休"时略低于上坡;Pn在中坡10时达到全天最高值7.53μmol·m~(-2)·s~(-1),而上坡在11时达到全天最大值7.03μmol·m~(-2)·s~(-1);叶片蒸腾速率(Tr)日变化在9:00~12:00中坡高于上坡,在12:00~15:00低于上坡。(3)圆果化香在中坡的叶片叶绿素a、b和总叶绿素含量分别比上坡高74.35%、80.89%、76.57%,丙二醛含量中坡小于上坡。(4)圆果化香叶片的平均长、宽、叶面积、叶片干重均为中坡大于上坡,而比叶面积上坡大于中坡;球果直径在中坡为2.65±0.16cm,比上坡大31.84%,球果的平均种子数量比上坡多27个。综合而言:由于坡位的差异,上坡土壤养分比中坡低得多,不能很好地供给植物生长;上坡圆果化香在水分输入方面不及中坡,而在水分输出方面高于中坡且调控不及时和不合理;在一天的光合作用中,中坡能积累更多的光合产物。 相似文献
165.
166.
Photo-catalytic decolourisation of toxic dye with N-doped titania: A case study with Acid Blue 25 总被引:1,自引:0,他引:1
Dyes are one of the hazardous water pollutants.Toxic Acid Blue 25,an anthraquinonic dye,has been decolourised by photo-catalysing it with nitrogen doped titania in aqueous medium.The photo catalyst was prepared from 15% TiCl 3 and 25% aqueous NH 3 solution as precursor.XRD and TEM revealed the formation of well crystalline anatase phase having particle size in the nano-range.BET surface area of the sample was higher than that of pure anatase TiO 2.DRS showed higher absorption of radiation in visible range compared to pure anatase TiO 2.XPS revealed the presence of nitrogen in N-Ti-O environment.The experimental parameters,namely,photocatalyst dose,initial dye concentration as well as solution pH influence the decolourisation process.At pH 3.0,the N-TiO 2 could decolourise almost 100% Acid Blue 25 within one hour.The influence of N-TiO 2 dose,initial concentration of Acid Blue 25 and solution pH on adsorption-desorption equilibrium is also studied.The adsorption process follows Lagergren first order kinetics while the modified Langmuir-Hinselwood model is suitably fitted for photocatalytic decolourisation of Acid Blue 25. 相似文献
167.
Simultaneous determination of brominated phenols in soils 总被引:1,自引:0,他引:1
Brominated phenols (BPs), a widely used group of emerging flame retardants, are important environmental contaminants and exhibit endocrine disrupting potential. Method for simultaneous determination of tetrabromobisphenol A (TBBPA), tribromophenol (TBP), dibromophenols (DBPs) and monobromophenols (MBPs) in soils using gas chromatography-mass spectrometry analysis (GC/MS) was successfully developed. Cleanup methods for soil extracts including several solid-phase extraction cartridges and different elution solvents were compared and optimized. Florisil cartridge with dichloromethane as the elution reagent was selected for sample cleanup owing to its high and reproducible recoveries of the target analytes in soils. Derivatization conditions were tested and the optimal conditions were obtained with 20 μL silylation reagent at room temperature. The chromatographic separation was optimized with different columns and DB-XLB column was selected for its excellent separation of the analytes. The limits of detection for the target compounds were from 0.04 to 0.19 ng/g. Mean recoveries of the compounds from spiked soils exceeded 84% with a good reproducibility, excepting that the recovery of 2-bromophenol was relatively poor (lower than 55%) due to its instability. The developed method was applied to the determination of the BPs in the soils collected from e-waste sites. The contents of BPs in the soils were at ng/g levels with TBBPA and TBP the most frequently detected. To our knowledge, this is the first report for the simultaneous determination of TBBPA, TBP, DBPs and MBPs in soils. 相似文献
168.
Theera Tongsong Pimlak Charoenkwan Pannee Sirivatanapa Chanane Wanapirak Wirawit Piyamongkol Supatra Sirichotiyakul Kasemsri Srisupundit Fuanglada Tongprasert Suchaya Luewan Thawalwong Ratanasiri Ratana Komwilaisak Piyamas Saksiriwuttho Chutawadi Vuthiwong Peerapun Punpuckdeekoon Prisana Panichkul Wibool Rueangchainikhom Jirawat Choowong Nawaporn Orungrote Sravuth Sarapak Ekachai Kovavisarach Prapon Jaruyawongs Thitinan Tansathit Podjanee Phadungkiatwattana Jittima Rujiwetpongstorn Ounjai Kor-anantakul Chitkasaem Suwanrath Tharangrut Hanprasertpong Savitree Pranpanus 《黑龙江环境通报》2013,33(5):477-483
169.
170.
针对火灾情况下油罐区的保护问题,设计了一种储罐冷却材料喷涂装置。装置通过“动”、“静”结构结合的设计方案,满足了对高吸水性聚合物冷却材料的混配溶胀与喷涂要求。利用FLUENT软件对新型旋流静态混合器的分析结果表明,新型旋流静态混合器切向速度大,径向混合能力和湍流扩散能力强,有利于实现良好的混合效果。 相似文献