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1.
铜是人类使用最早的金属。铜及其化合物在人类生产和生活中有着极其广泛的应用。本文从铜的使用历史、铜及其化合物、铜的广泛应用、铜的冶炼等方面论述了铜在人类文明的发展和推动科学技术的进步中的重要作用。  相似文献   

2.
在合成氨工厂里,为了精制原料气,目前普遍采用铜氨液进行“铜洗”,在这个过程中,产生了一种表面带蓝的黑色沉淀物,即铜洗废渣。据分析,它含铜35—40%,主要成分是硫化亚铜、硫化铜以及碳酸铜、醋酸亚铜络二氨、单质铜、硫化亚铁、硅酸钙、二氧化硅等多种物质。过去,这种废渣被人们忽视和遗弃。我们遵照毛主席有关综合利用的教导,在领导支持和工人同志的帮助下,经过反复试验,终于比较成功地用土办法从铜洗废渣中炼出了紫铜。一年多来,已回收五百多斤,送交福州氮肥厂补充铜耗,效果良好。  相似文献   

3.
李刚  李小红  张治军 《化学进展》2011,23(8):1644-1656
纳米铜由于其独特的物理化学性质以及在光学、电子、催化、抗菌、润滑、聚合物填充改性等领域的广泛应用得到了人们越来越多的关注。近年来研究者已经利用多种合成方法制备了不同尺寸和形貌的铜纳米材料。本文综述了目前铜纳米材料的几种常用的制备方法,包括化学还原法、微乳液法、多元醇法、有机前驱体热分解法、电化学法等,评述了这些方法的优缺点。在化学还原法中配体对无机纳米材料的表面修饰起着至关重要的作用,因而我们详细介绍了不同分子配体在铜纳米材料尺寸和形貌控制以及表面功能化等方面的特点和作用。最后结合本课题组在纳米材料制备方面的工作,对铜纳米材料的发展进行了展望。  相似文献   

4.
铜纳米簇不仅具有金属纳米簇的特异性,还有前驱体价格便宜等优点,因此有广泛的应用前景。从配体辅助法、模板法、微波法、电化学法和刻蚀法等综述了铜纳米簇的制备方法。从离子诱导聚集、pH诱导聚集、组装诱导聚集和溶剂诱导聚集增强发射等方面综述了铜纳米簇聚集诱导荧光发射增强性能。从离子检测、小分子检测、酶活性检测、生物大分子检测和生物成像等方面综述了铜纳米簇的应用,并对铜纳米簇的制备、性能优化和应用等方面作了展望。  相似文献   

5.
崔娜  张晓娟  王志明 《合成化学》2017,25(4):360-368
高选择性、超灵敏性铜离子荧光探针的设计和开发,在环境检测、食品安全及人体内微量铜元素探测等领域具有重要意义。本文根据荧光分子探针对铜离子的识别机制和化学结构特点,从罗丹明、香豆素、芘基团、萘酰亚胺、氟硼吡咯及其他荧光基团等发色团出发,综述了近年来铜离子荧光探针的研究进展。参考文献27篇。  相似文献   

6.
李强  辜敏  鲜晓红 《化学进展》2008,20(4):483-490
铜具有的优良导电性和机械加工性能以及其电沉积工艺的诸多优点,决定了铜电沉积在各行业特别是近年在高新技术中的广泛应用。铜的电结晶过程是铜电沉积的初期阶段,它决定了后续的电沉积过程及最终镀层的结构和性能,因此一直是研究的热点。本文综述了铜电结晶的研究方法、电结晶理论研究的进展,详细讨论了pH值、添加剂、金属离子、基体以及电沉积条件等因素对铜电结晶的机理和成核动力学的影响,并对研究中存在的问题提出了展望。  相似文献   

7.
铜铁矿型氧化物材料在催化剂、发光材料、太阳能电池、臭氧传感器和p型透明导电氧化物等领域有广阔的应用前景,已成为研究的热点。本文阐述了水热法制备铜铁矿材料的基本原理和特点,介绍了水热法制备纳米铜铁矿材料的最新研究进展。  相似文献   

8.
在现代纳米科学技术领域中,铜纳米线由于具有独特的光学、电学、力学和热学性质而成为制备透明柔性导电电极的优良材料。铜价格低廉,自然存储量较大,是实际应用中替代贵金属的理想材料。然而,将铜离子还原为单质铜比较困难,且单质铜非常容易被氧化,这成为应用中亟需解决的关键问题。如何制备单分散、稳定且具有抗氧化性的铜纳米线也成为该领域的研究热点。在各种制备铜纳米线的方法中,液相还原法不仅可以解决以上问题,且该方法具有制备条件限制少、成本低、简单易行等优点而被广泛应用于铜纳米线的大量合成。本文从铜纳米线的研究背景和研究价值入手,首先综述了不同(光滑或粗糙、单晶或孪晶)铜纳米线的液相制备方法及其生长机制。讨论了铜纳米线的氧化及其抗氧化表面包覆问题。最后对铜纳米线的研究意义和应用前景做出展望。  相似文献   

9.
目前国内铜精矿供应紧俏,铜冶炼行业的原料复杂,有些偏离了认证和认可标准方法的样品,在检测时,用认证、认可文件不能很好地进行质量管控,需要对分析方法加以改进,从技术上进行管控。结合国内铜冶炼企业的实际情况和多年的实践经验,从样品的加工和保存环节、铜分析的技术环节、人员培训、质量抽查、定期开展质量分析会等方面对铜的分析质量控制进行了总结。在具体的质量控制中,针对铜冶炼行业成分复杂、易变化的物料分析,应根据实际情况进行质量管控,以提高铜分析的准确度。  相似文献   

10.
以铜锰硝酸、铜锰硫酸、铜锰醋酸和铜锰氯化盐为前驱体,采用共沉淀法制备了铜锰催化剂,利用XRD、TPR、STPR(表面氧化程序升温还原)、TPD和XPS等对样品进行了表征,并考察了其水煤气变换反应催化性能.结果表明,所制备的催化剂主晶相均为尖晶石结构的Cu1.5Mn1.5O4金属固溶体,经变换反应后均被还原分解为Cu和Mn O,其中以铜锰醋酸盐制备得到的样品出现了较为明显的Mn CO3特征衍射峰.铜锰醋酸盐制备的样品因单质铜和氧化锰协同效应良好,可显著增加对CO2的吸附能力,提高其表面铜的分散性,具有良好的热稳定性和低温变换反应活性.以铜锰硝酸盐制备的样品在400~450℃维持了较高的热稳定性及催化活性,但在300℃以下CO转化率明显下降,而以铜锰硫酸盐及铜锰氯化盐制备的样品在200~450℃测试温区内催化性能较差.  相似文献   

11.
An atomic absorption spectrophotometric method for the determination of trace copper after adsorption of its 1-nitroso-2-naphthol-3,6-disulfonic acid chelate on Ambersorb 572 has been developed. This chelate is adsorbed on the adsorbent in the pH range 1–8. The copper chelate is eluted with 5 ml of 0.1 mol l−1 potassium cyanide and determined by flame atomic absorption spectrometry (FAAS). The selectivity of the proposed procedure was also evaluated. Results show that iron(III), zinc(II), manganese(II) and cobalt(II) at the 50 μg l−1 level and sodium(I), potassium(I), magnesium(II), calcium(II) and aluminium(III) at the 1000 μg l−1 level did not interfere. A high enrichment factor, 200, was obtained. The detection limit (3σ) of copper was 0.34 μg l−1. The precision of the method, evaluated by seven replicate analyses of solutions containing 5 μg of copper was satisfactory and the relative standard deviation was 1.7%. The adsorption of copper onto Ambersorb 572 can formally be described by a Langmuir equation with a maximum adsorption capacity of 14.3 mg g−1 and a binding constant of 0.00444 l mg−1. The accuracy of the method is confirmed by analysing tomatoes leaves (NIST 1573a) and lead base alloy (NBS 53e). The results demonstrated good agreement with the certified values. This procedure was applied to the determination of copper in waters (tap, river and thermal waters), aluminium foil and tea samples.  相似文献   

12.
Methods for the determination of aluminium and manganese in human scalp hair samples by electrothermal atomic absorption spectrometry using the slurry sampling technique were developed. Palladium and magnesium nitrate were used as chemical modifiers. Hair samples were pulverized using a zirconia vibrational mill ball, and were prepared as aqueous slurries. Determinations can be performed in the linear ranges of 1.9–150 μg l−1 Al3+ and 0.03–10.0 μg l−1 Mn2+. Limits of detection of 0.9 mg kg−1 and 27.6 μg kg−1 were obtained for aluminium and manganese, respectively. The analytical recoveries were between 99.6 and 101.8% for aluminium and in the 98.3–101.3% range for manganese. The repeatability of the methods (n=11), slurry preparation procedure and ETAAS measurement, was 16.0 and 7.9% for aluminium and manganese, respectively. The methods were finally applied to the aluminium and manganese determination in 25 scalp hair samples from healthy adults. The levels for aluminium were between 8.21 and 74.08 mg kg−1, while concentrations between 0.03 and 1.20 mg kg−1 were found for manganese.  相似文献   

13.
铜-四(4-三甲胺苯基)卟啉配合物吸附波研究   总被引:1,自引:0,他引:1  
本文研究了铜-四(4-三甲胺苯基)卟啉配合物在汞电极上的吸附行为及其反应机理。实验证明,该配合物强烈地吸附在电极上,配合物中配位体和钢离子同时还原产生灵敏的配合物吸附波。将该吸附波用于多种样品分析,得到了较好的结果。  相似文献   

14.
Castro MT  Baccan N 《Talanta》2005,65(5):1264-1269
In the present paper, a procedure for preconcentration and determination of copper in soft drink using flame atomic absorption spectrometry (FAAS) is proposed, which is based on solid-phase extraction of copper(II) ions as its ion pair of 1,10-phenanthroline complexes with the anionic surfactant sodium dodecil sulphate (SDS), by Amberlite XAD-2 resin. The optimization process was carried out using 24–1 factorial and 22 factorial with a center point designs. Four variables (XAD-2 mass, copper mass, sample flow rate and elution flow rate) were regarded as factors in the optimization. Student's t-test on the results of the 24–1 factorial design with eight runs for copper extraction, demonstrated that the factors XAD-2 mass and sample flow rate in the levels studied are statistically significant. The 22 factorial with a center point design was applied in order to determine the optimum conditions for extraction. The procedure proposed allowed the determination of copper with detection limits (3/S) of 3.9 μg l−1. The precision, calculated as relative standard deviation (R.S.D.) was 1.8% for 20.0 μg l−1 of copper. The preconcentration factor was 100. The robustness of this procedure is demonstrated by the recovery achieved for determination of copper in the presence of several cations. This procedure was applied to the determination of copper in soft drink samples collected in Campinas, SP, Brazil.  相似文献   

15.
Ion chromatography was applied to the determination of aluminium and its fluoro complexes in natural waters. The separation was carried out on a cation-exchange column. The aluminium species were detected by postcolumn reaction with Tiron followed by UV spectrophotometry. The method requires the adjustment of the pH and ionic strength of the sample to those of the mobile phase immediately prior to injection. Al3+ , AlF2+ and AlF2+ are eluted separately while all hydroxo complexes are readily dissociated and eluted along with Al3+ under these conditions. The sum of peak areas, which represents the total aluminium concentration, was conserved whatever the amount of fluoride in the sample. Linearity of calibration was observed over the range 20–2000 μg 1−1. Further, the speciation of fluoro-aluminium complexes as determined experimentally by ion chromatography is in good agreement with calculations based on complexation constants. The applications and limitations of the method are discussed.  相似文献   

16.
Hassan SS  Ali MM  Attawiya AM 《Talanta》2001,54(6):1153-1161
Two novel uranyl PVC matrix membrane sensors responsive to uranyl ion are described. The first sensor incorporates tris(2-ethylhexyl)phosphate (TEHP) as both electroactive material and plasticizer and sodium tetraphenylborate (NaTPB) as an ion discriminator. The sensor displays a rapid and linear response for UO22+ ions over the concentration range 1×10−1–2×10−5 mol l−1 UO22+ with a cationic slope of 25.0±0.2 mV decade−1. The working pH range is 2.8–3.6 and the life span is 4 weeks. The second sensor contains O-(1,2-dihydro-2-oxo-1-pyridyl)-N,N,N′,N′-bis(tetra-methylene)uronium hexafluorophosphate (TPTU) as a sensing material, sodium tetraphenylborate as an ion discriminator and dioctyl phenylphosphonate (DOPP) as a plasticizer. Linear and stable response for 1×10−1–5×10−5 mol l−1 UO22+ with near-Nernstian slope of 27.5±0.2 mV decade−1 are obtained. The working pH range is 2.5–3.5 and the life span of the sensor is 6 weeks. Interference from many inorganic cations is negligible for both sensors. However, interference caused by some ions (e.g. Th4+, Cu2+, Fe3+) is eliminated by a prior ion exchange or solvent extraction step. Direct potentiometric determination of as little as 5 μg ml−1 uranium in aqueous solutions shows an average recovery of 97.2±1.3%. Application for the determination of uranium at levels of 0.01–1 wt.% in naturally occurring and certified ores gives results with good correlation with data obtained by X-ray fluorescence.  相似文献   

17.
Goto K  Taguchi S  Fukue Y  Ohta K  Watanabe H 《Talanta》1977,24(12):752-753
A spectrophotometric method for the determination of trace amounts of manganese with 1-(2-pyridylazo)-2-naphthol (PAN) is described. The method is based on the measurement of absorbance of the manganese—PAN chelate solubilized with a non-ionic surfactant, Triton X-100. No extraction procedure is required in the method proposed. High concentrations of calcium, aluminium and magnesium do not interfere. The presence of up to 10 ppm of lead can be tolerated. Iron, cadmium, zinc, cobalt and nickel can be effectively masked with potassium cyanide. Beer's law is obeyed up to 2 ppm of manganese. The molar absorptivity of the manganese—PAN chelate found was 4.4 × 104 l. mole −1. cm−1 at 562 nm. The overall stability constant of Mn(PAN)2 in 0.4% Triton X-100 medium is 1016.8.  相似文献   

18.
本文利用无水皂化萃取剂加水生成微乳状液研究离子水化的新方法,研究了酸性膦酸酯D2EHPA(碱金属盐)-ROH-煤油-水体系中,通过对水质子化学位移变化的规律来研究碱金属的水合作用,所得结果与环烷酸体系相似。当[M+]/[H2O]从100/1向1/100变化时,可以看到配位水的化学位移比缔合水(即正常液体水)向低场移动近2ppm,这比通常在浓盐水溶液中观察到的差值提高了一个数量级。当[M+]/[H2O]大于100/1时,配位水的化学位移随阳离子不同而趋于不同的极限值,其顺序为NH4+(6.76)>Li+(6.60)>Na+(5.96)>K+(5.40)。 从不同体系NMR图峰形和半高宽度Δv1/2的变化,可以观察到阴离子的结构和组成对离子的水化作用有较大的影响。有关阴离子水合情况的研究工作正在进行中。  相似文献   

19.
Reaction of L {L = [24]aneS8, [28]aneS8} with two molar equivalents of [Cu(NCMe)4]X (X = ClO4, BF4, PF6) in MeCN affords the white binuclear copper(I) complexes [Cu2(L)]2+. A single crystal X-ray structure determination of [CU2([24]aneS8)](BF4)2 shows two tetrahedral copper(I) centres, each of which is coordinated to four thioether sulphur-donors, Cu---S(1) = 2.263(3), Cu---S(4) = 2.363(3), Cu---S(7) = 2.349(3), Cu---S(10) = 2.261(3) Å. The Cu … Cu distance is 5.172(3) Å. A single crystal X-ray structure determination Of [CU2([28]aneS8)](ClO4)2 shows that this complex also contain two tetrahedral copper(I) centres, each coordinated to four thioether sulphur-donors, Cu---S(1) = 2.278(5), Cu---S(4) = 2.333(5), Cu---S(8) = 2.328(5), CU---S(11) = 2.268(5) Å. The Cu … Cu distance of 6.454(3) Å is greater than in [CU2([24]aneS8)]2+ , reflecting the greater cavity size in [CU2([28]aneS8)]2+. Cyclic voltammetry of [CU2([24]aneS8)]2+ and [CU2([28]aneS8)]2+ at platinum electrodes in MeCN (0.1 M nBU4NPF6) shows irreversible oxidations at Epa, = +0.88 V, +0.92 V vs Fc/Fc+, respectively, at a scan rate of 200 mV s−1. Coulometric measurements in MeCN confirm these oxidations to be two-electron (one electron per copper) processes to give binuclear copper(II) species. Oxidation of the binuclear copper(I) precursors with H2SO4 or HNO3 affords ESR-active copper(II) species which presumably incorporate SO42− and NO3 bridges.  相似文献   

20.
Na2MnPO4F材料是一种很有发展前景的钠离子电池正极材料,本文通过非原位XRD和固体核磁共振技术研究该材料充放电结构变化(晶体结构与局域Na位). 非原位XRD测试发现,充电过程在2θ为31o和36o左右出现新的衍射峰,表明钠脱出后电极上有中间相物质生成. 23Na MAS NMR谱图的-209 ppm、-258 ppm和-295 ppm三个谱峰分别对应于该材料结构中Na1 + Na2位、Na3位和Na4位. 非原位23Na MAS NMR谱研究发现,充电过程中-209 ppm处信号峰面积比例减小,表明Na1和Na2位的Na比Na3和Na4位先脱出. 充电至4.2 V,-132 ppm和-330 ppm处出现中间相物质的信号峰;而放电过程则相反.  相似文献   

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