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991.
用微波消解技术对螺旋藻试样进行预处理,针对样品高蛋白特性,优化较佳的微波消解条件与参数,建立了用微波消解-石墨炉原子吸收法测定螺旋藻中铁、锌、镁、钙、钾、钠、铜、锰等微量元素的测定方法。该方法可减少样品预处理过程的损失,具有准确、快捷、方便的特点,回收率达96.4%-101.2%;RSD为0.8%-2.5%。 相似文献
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993.
Non-thermal plasma technology is a promising process for flue gas treatment. Microwave catalytic NOx and SO2 removal simultaneously has been investigated using FeCu/zeolite as catalyst. The experimental results showed that a microwave reactor with FeCu/zeolite only could be used to microwave catalytic oxidative 91.7% NOx to nitrates and 79.6% SO2 to sulfate; the reaction efficiencies of microwave catalytic reduction of NOx and SO2 in a microwave reactor with FeCu/zeolite and ammonium bicarbonate (NH4HCO3) as a reducing agent could be up to 95.8% and 93.4% respectively. Microwave irradiation accentuates catalytic reduction of SO2 and NOx treatment, and microwave addition can increases SO2 removal efficiency from 14.5% to 18.7%, and NOx removal efficiency from 13.4% to 18.7%, separately. FeCu/zeolite catalyst was characterized by X-ray diffraction (XRD), X-ray photoelectron spectrum analysis (XPS), scanning electron microscopy (SEM) and the Brunauer Emmett Teller (BET) method. Microwave catalytic NOx and SO2 removal follows Langmuir-Hinshelwood (L-H) kinetics. 相似文献
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995.
褐煤干燥提质技术浅谈 总被引:2,自引:0,他引:2
介绍褐煤的基本性质和几种褐煤的干燥提质技术,如管式干燥技术、蒸汽流化床干燥技术(DWT法)、热脱水工艺和LFC褐煤干燥等,简单分析各工艺,展望褐煤干燥提质的前景. 相似文献
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997.
998.
西北某车辆厂含油废水为达到回用水要求,需对其进行深度处理。混凝作为预处理,其效果好坏直接影响气浮及精细过滤,为此进行了影响混凝效果因素的正交试验。通过研究确定出适合该厂水质的混凝预处理控制条件为:混凝剂种类为PAC(I),投加量为30 mg/L,搅拌速度250 r/min,搅拌时间90 s,助凝剂用量为0.4 mg/L。使混凝后出水浊度、COD、油分别在4.5 NTU、55 mg/L、6.0 mg/L左右,与原来混凝后出水浊度10~26 NTU、COD60~92 mg/L、油7.4~10.6 mg/L相比有较大提高,为后续处理作了稳定可靠地保。 相似文献
999.
Gui‐Ying Liao Liang Chen Xiao‐Yong Zeng Xing‐Ping Zhou Xiao‐Lin Xie E‐Jun Peng Zhang‐Qun Ye Yiu‐Wing Mai 《应用聚合物科学杂志》2011,120(4):2154-2165
Polymer blending is one of the most effective methods for providing new, desirable biocomposites for tissue‐engineering applications. In this study, electrospun poly(L ‐lactide)/poly(ε‐caprolactone) (PLLA/PCL) blend fibrous membranes with defect‐free morphology and uniform diameter were optimally prepared by a 1 : 1 ratio of PLLA/PCL blend under a solution concentration of 10 wt %, an applied voltage of 20 kV, and a tip‐to‐collector distance of 15 cm. The fibrous membranes also showed a porous structure and high ductility. Because of the rapid solidification of polymer solution during electrospinning, the crystallinity of electrospun PLLA/PCL blend fibers was much lower than that of the PLLA/PCL blend cast film. To obtain an initial understanding of biocompatibility, adipose‐derived stem cells (ADSCs) were used as seed cells to assess the cellular response, including morphology, proliferation, viability, attachment, and multilineage differentiation on the PLLA/PCL blend fibrous scaffold. Because of the good biocompatibility and nontoxic effect on ADSCs, the PLLA/PCL blend electrospun fibrous membrane provided a high‐performance scaffold for feasible application in tissue engineering using ADSCs. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
1000.
The effects of organic montmorillonite (OMMT) on the rheological behaviors and phase morphology of polylactide (PLA) were investigated. The rheological behaviors of nanocomposites showed mainly dependence on both temperature and OMMT content. At low OMMT loading (1 wt %), the complex viscosities showed a Newtonian plateau in low frequency region at low temperatures and converted to a shear‐thinning behaviors with increasing temperature. In comparison, at high OMMT loadings (above 5 wt %), strong shear‐thinning behaviors were observed in the full range of frequencies and temperatures. The results demonstrated rheology of PLA/OMMT is highly sensitive to the nanofillers filled materials. A pseudo‐solid‐like behavior at long scale time in the hybrids with OMMT loading was higher than 5 wt %, this response was related to the formation of a network structure across the polymer matrix due to strong interactions of PLA and OMMT that confined the relaxation process of the macromolecules. X‐ray diffraction and transmission electron microscopy indicated the nanocomposites at low OMMT loading were mainly exfoliated and intercalated nanocomposites were gradually formed with increasing OMMT loading. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献