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81.
研究了硫酸铵-硫酸铜-十六烷基三甲基溴化铵-湿法磷酸体系浮选碘(I-)的行为及其与常见离子分离的条件。试验表明,在1.0g(NH4)2SO4存在下,体系中硫酸铜和十六烷基三甲基溴化铵(CTMAB)的用量分别为(2.4×10-2mol/L)0.5ml和0.025g,I-与Cu(Ⅱ)形成的CuI沉淀能被CTMAB浮选,而其它非金属离子不被浮选,从而实现碘(I-)与这些离子之间的定量分离。本法对湿法磷酸中微量碘进行了定量浮选分离,结果满意。 相似文献
82.
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84.
赵微 《齐齐哈尔轻工业学院学报》2010,(4):79-82
讨论{um+ρ3u=f(t,u),t∈I=(0,2π),u(i)(0)=u(i)(2π),i=0,1,2ρ∈(0,1/3)是常数三阶微分方程的周期边值问题的多个正解存在性问题。通过与一个线性算子相关的第一特征值的讨论,运用锥拉伸与压缩不动点定理,得到上述边值问题多个正解存在的结果。 相似文献
85.
王进祥 《佳木斯工学院学报》2010,(2):317-318
用一种较简单的方法建立了非线性四阶常微分方程边值问题{u(4)(t)=f(t,u9t),u″(t)0,t∈(0,1) u(0)=u(1)=u″(0)=u″(1),正解的存在性结果,对非线性项f只要求其满足一个局部条件. 相似文献
86.
在文献[1-2]的基础上,研究了非线性差分方程xn+1=a-bxpn-k/A-x2n的全局稳定性和正解的周期性,其中a,A为非负实数,b为正实数,k,p∈{1,2,…},p≥2.证明了该方程的一个正平衡点是一个全局吸引子,并给出了相应的吸引域. 相似文献
87.
In order to extract froth morphological feature, a bubble image adaptive segmentation method was proposed. Considering the
image’s low contrast and weak froth edges, froth image was coarsely segmented by using fuzzy c means (FCM) algorithm. Through
the attributes of size and shape pattern spectrum, the optimal morphological structuring element was determined. According
to the optimal parameters, some image noises were removed with an improved area opening and closing by reconstruction operation,
which consist of image regional markers, and the bubbles were finely separated from each other by watershed transform. The
experimental results show that the structural element can be determined adaptively by shape and size pattern spectrum, and
the froth image is segmented accurately. Compared with other froth image segmentation method, the proposed method achieves
much high accuracy, based on which, the bubble size and shape features are extracted effectively. 相似文献
88.
Froth flotation is used widely for upgrading raw phosphate. The flotation recovery of coarse phosphate (-1.18+0.425 mm) is much lower than that achieved on the -0.425+0.15 mm size fraction. Enhanced recovery of coarse phosphate particles is of great economic and environmental importance for phosphate industry. In this investigation, four different phosphate samples were aquired, characterized and tested in a specially designed laboratory-scale flotation column. Significant recovery improvement of coarse phosphate flotation was achieved using cavitation-generated nanobubble though its effects differ among the four testing phosphate samples. The laboratory-scale flotation column test results indicate that nanobubble increased P2O5 recovery by up to 10%-30% for a given Acid Insoluble (A.I.) rejection, depending on the characteristic of phosphate samples. The improvement ef-fect of nanobubble on the hard-to-float particles was more significant than that on easy-to-float particles, especially at lower col-lector dosages. Nanobubbles reduced the collector dosage by 1/3 to 1/2. Nanobubbles almost doubled the coarse phosphate flotation rate constant and increased the flotation selectivity index by up to 25%. 相似文献
89.
The flotation of pure and natural carbonaceous iron ore samples in the oleate flotation system was investigated. Starch can
depress hematite effectively in a wide pH range, but cannot depress siderite efficiently in neutral conditions. The flotation
recovery of pure hematite, siderite, and quartz in the oleate-starch-CaCl2 system is significantly different when the slurry pH varies from 4 to 12. A novel two-step flotation process was developed
for the separation of iron concentrate from Donganshan carbonaceous iron ore through which the siderite concentrate is first
recovered and the high quality hematite concentrates with relative high iron recovery can be obtained in the second step flotation.
The siderite concentrate may be utilized directly or undergo further concentration steps to increase iron grade. 相似文献
90.
FCLS (Ferric Chromium Lignin Sulfonate) was used to aid the separation of chalcopyrite from marmatite. Flotation, adsorption and zeta-potential tests of treated marmatite and chalcopyrite were performed. The flotation of marmatite was strongly depressed, while that of chalcopyrite was only slightly depressed, over a wide range of pH values when FCLS was used as depressant in the presence of Butyl Xanthate (BX). The adsorption of BX onto chalcopyrite or marmatite takes place over a wide pH range. The adsorption density of BX on chalcopyrite and marmatite decreases as the pH increases. The adsorption density of FCLS onto marmatite is greater than the adsorption density onto chalcopyrite. The zeta potentials of chalcopyrite and marmatite become more negative due to the addition of xanthate and FCLS. 相似文献