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61.
62.
Shiheng Yin Dongxiao WuJi Yang Shumei LeiTongchun Kuang Bin Zhu 《Applied Surface Science》2011,257(20):8481-8485
Biomimic superhydrophobic surfaces with contact angle greater than 150° and low sliding angle on copper substrate were fabricated by means of a facile solution immersion and surface self-assembly method. The scanning electron microscopy showed a nanoneedle structure copper surface with sporadic flower-like aggregates after treatment with sodium hydroxide and potassium persulfate solution. X-ray photoelectron spectroscopy and X-ray diffraction results confirmed that the formed nanoneedles were crystallized Cu(OH)2. And the hydrophilic Cu(OH)2 surface can be further modified into superhydrophobic through surface self-assembly with dodecanoic acid. 相似文献
63.
B. Macalik L. Krajczyk J. Okal T. Morawska-Kowal K. D. Nierzewski M. Suszyńska 《辐射效应与固体损伤》2013,168(6-12):887-893
The ion-exchange process was used to introduce copper ions into soda lime silicate glasses (SLS), the composition of which corresponds to the miscibility gape in the Na 2 O-SiO 2 system. The samples have been immersed either in a molten Cu 2 Cl 2 or CuCl 2 at various temperatures from the range 720-940 v K for different time. The observed green colour of glass is related with the 790-nm absorption band related to the cupric ions. The annealing either in air or in the hydrogen atmosphere was used for the reduction of copper. The effectiveness of these procedures was analysed on a basis of the penetration profiles monitored by roentgenographic methods (diffraction and EDAX). Transmission electron microscopy (TEM) observations of the replicated surface and common optical absorption measurements have been used to study the morphology of the dopant ions. 相似文献
64.
《辐射效应与固体损伤》2013,168(1-6):375-381
Glass ceramics of the composition (Bi0.8Pb0.2)4Sr3Ca3Cu4O8 prepared by the melt quenching technique and the crystalline phases produced by the rapid thermal annealing have been studied by electrical resistivity and electron paramagnetic resonance (EPR) measurements in the temperature range from liquid helium up to room temperature. The concentration of the EPR active Cu2? paramagnetic centers decreases as conductivity increases for the glass ceramics and disappears after crystallization and the growth of superconducting phases, similar to bulk high-Tc superconductors. The KPR spectra of both glass and crystallized ceramics after short-time annealing indicate the coexistence of Cu2? paramagnetic ions and the exchange coupled clusters. 相似文献
65.
Mehmet Yaman 《光谱学与光谱分析》2013,32(5):1331-1337
The aim of this study is to examine seasonal changes in Cu and Co concentrations of three plant species for monitoring the effects of pollution in Elazig,Turkey.For this purpose,the leaves of the Pinus nigra L.,Cedrus libani and Cupressus arizonica together with soil samples were collected from different points depending on traffic intensity,nearness the city center and cement factory as well as control location during different months of the year.Flame atomic absorption spectrophotometer(FAAS) was used for measurement of the metals in clear digests after the dry ashing method.Copper and Co concentrations were in the ranges from 1.3to 2.6mg.kg-1 and相似文献
66.
“海纹石”的矿物学及谱学特征研究 总被引:1,自引:0,他引:1
“海纹石”是具有蓝色条带的针钠钙石,是一种稀有的宝石材料,具有较好的市场前景。为查明其矿物学特征及成因,采用常规宝石学测试并结合X射线衍射(XRD)、傅里叶红外吸收光谱(FTIR)、拉曼光谱(Raman)、扫描电镜(SEM)及紫外-可见分光光度计(UV-Vis)等现代测试方法,对“海纹石”不同颜色部分的矿物成分及特征进行了深入分析。XRD,FTIR,Raman分析结果表明,“海纹石”的主要组成矿物为针钠钙石,并含有少量的方解石,与SEM分析结果较为一致。FTIR分析显示,“海纹石”白色部分在1 500 cm-1处出现一个明显的宽吸收带并伴有883和710 cm-1的吸收峰,表明含有少量方解石,而蓝色部分在该处没有此吸收。紫外可见吸收光谱分析显示蓝色部分在可见光区有640 nm宽吸收峰,表明可能含有微量元素Cu。“海纹石”白色和蓝色部分矿物组分的差异,表明两者可能形成于不同的地质环境。 相似文献
67.
The results of laser induced deposition of copper on polyimide substrate from copper electrolyte solution are reported. Unlike most work reported in the literatures where CW Ar+ lasers were used, a second harmonic (532 nm wavelength) Q-switch Nd:YAG laser was used for our experiments. The deposition process was conducted by laser-catalyzing of the polyimide surface and subsequent photothermal-accelerated reduction of copper-complex ions in an alkaline reducing environment. The characteristics of the deposited copper line were investigated in terms of laser beam scanning speed, and the number of scans. The surface morphology and chemical composition of the deposited copper were analyzed using field emission scanning electron microscope (FESEM) and energy dispersive spectrometer (EDX). The optimum processing conditions have been identified. The copper deposit was found to adhere well to the substrate. 相似文献
68.
69.
ICP-AES测定饮用水源中的Cu、Mn、Pb、Cd、Zn 总被引:5,自引:2,他引:5
用ICP-AES法同时测定饮用水源中的Cu、Mn、Pb、Cd、Zn等重金属元素,具有基体效应小、测量范围宽等优点。检出限为0.2-4.0μg/L,回收率为91.5%-103.9%,相对标准偏差为0.29%-1.5%,测定密码样与实际样品,结果令人满意。 相似文献
70.
离子交换富集-导数火焰原子吸收法测定自来水中Cu,Fe和Zn 总被引:7,自引:0,他引:7
本文研究了用 2 0 1× 7阳离子交换树脂对自来水中的微量元素进行交换富集 ,采用微量脉冲进样 导数火焰原子吸收法测定富集后溶液中的Cu ,Fe和Zn ,该方法灵敏度分别为 0 2 9,0 5 9和 0 0 6 μg·L- 1 ,精密度分别为 4 2 8% ,1 95 %和 2 2 8% ,检测限分别为 1 2 8,5 85和 0 6 8μg·L- 1 ,回收率分别为 91 13% ,10 1 34%和99 84 % ,本方法大大减少了需样量 ,简便快速 ,灵敏度高。 相似文献