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1.
常全明 《河北理工学院学报》1994,(1)
论述了冀东金矿集中区绿岩型金矿的矿质来源,并恢复其矿源层的原岩。对构造及中小型岩浆任入体的控矿作用作了论述,并提出了成矿模式。 相似文献
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《自然科学进展(英文版)》2019,29(6):655-659
A facile strategy for optical sensing of explosives with the assistance of 1,3,5-Triazine-2,4,6-triamine(MEL) in aqueous solution is proposed. Upon exposure to MEL, the electron-sufficient amino group in MEL was prone to form complexes with electron-deficient nitro group in explosives. The interaction could be tuned by the amount of MEL to fully consumed nitro-contained explosives dissolved in wastewater, thus prevented the gold nanoparticles(GNPs) from combining with MEL. In comparison with common detection method, the dose-response curve procedure reported here was in good linear relationship from 0 μM to 80 μM with good correlation factor(R~2= 0.9871), and was satisfactorily agreed with the proposed theoretical model. The detection limit(Lo D) was1.1 μM by spectrometer, 3.0 μM visualized by naked eyes and 21.3 nM by calculation. The procedure described in this study could be finished within a few minutes and showed its effectiveness in explosive detection upright on the gold surface in real wastewater, making this proposed method a powerful tool in several sensing platforms. 相似文献
4.
A novel glucose biosensor based on graphene nanosheets (GNs) modified gold nanowire arrays (AuN- WAs) electrode was constructed. Highly ordered gold nanowire arrays were prepared by direct electrodeposition in anodic aluminum oxide templates. GNs were synthe- sized through a public route involving graphite oxidation, exfoliation, and chemical reduction. Field emission scan- ning electron microscope and high-resolution transmission electron microscope were employed to characterize the as- prepared AuNWAs and GNs. Glucose oxidase was immobilized on the surface of GNs-AuNWAs modified electrode via a cross-linking method. The cyclic voltam- metry results showed that the GNs-AuNWAs-based glu- cose biosensors have high catalysis activity to hydrogen peroxide (H2O2) than those modified with GNs or AuN- WAs only. Furthermore, amperometric response was employed to detect glucose concentration owing to its simplicity, high selectivity, and relative low cost. Glucose biosensors based on GNs-AuNWAs showed excellent performance with high sen- sitivity of 40.25 μA cm^-2 (mmol/L)^-1, low detection limit of 0.02 mmol/L, and a linear range from 0.02 to 3 mmol/L. 相似文献
5.
The evolution of the optical absorption spectrum of bimetallic Ag-Au monolayer-protected clusters (MPC) obtained by progressively doping Ag into the experimentally known structure of Au133(SR)52 was predicted via rigorous time-dependent density-functional theory (TDDFT) calculations. In addition to monometallic Au133(SR)52 and Ag133(SR)52 species, 5 different (Ag-Au)133(SR)52 homotops were considered with varying Ag content and site positioning, and their electronic structure and optical response were analyzed in terms of Projected Density Of States (PDOS), the induced or transition electron density, and Transition Component Maps (TCM) at selected excitation energies. It was found that Ag doping led to the effects rather different from those encountered in bare metal clusters. And it was also observed that Ag doping could produce structured spectral features, especially in the 3–4 eV range but also in the optical region if Ag atoms were located in the sub-staple region, as rationalized by the accompanying electronic analysis. Additionally, Au doping into the staples of Ag-rich MPC also gave rise to a more homogeneous induced electron density. These findings show the great sensitivity of the electronic response of MPC nanoalloy systems to the exact location of the alloying sites. 相似文献
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本文用聚氨酯泡沫塑料作为柱材料,研究制定了在线预富集流动注射火焰原子吸收测定痕量金的新方法.实验溶液含金0.02μg/ml,酸度为5%~10%王水,以甲基异丁酮为洗脱液.当流速为16ml/min时,富集倍数为进样1min富集50倍.该方法选择性好,用于地质矿样中痕量金的测定,相对误差为1.1%. 相似文献
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扼要地介绍了Gold序列的产生及相关特性,提出了一种简单地求找相关函数方法;并从不同角度对典型的Gold序列的抗干扰容限进行了较为详细的讨论。 相似文献
9.
公婆泉铜矿岛弧型含矿斑岩地质地球化学特征 总被引:8,自引:1,他引:8
目前发现的斑岩型铜矿的含矿斑岩均产于陆相环境,公婆泉铜矿斑岩是目前为止发现的惟一产于海相环境的含矿斑岩,围岩沉积环境,岩石化学和地球化学研究表明,含矿次英安斑岩和花岗闪长斑岩产于海相环境,形成于水下500-1000m,是中一晚志留纪哈萨克斯坦板块向(南)塔里木-中朝板块俯促时公婆泉-东七一山岛弧岩浆晚期分异的产物。 相似文献
10.
杨正华 《山西师范大学学报:自然科学版》1994,8(3):60-64
石英脉金,是岩金的一个重要类型.金的富集与石英的形成与演化有着直接或间接的联系.因此,笔者以小秦岭金矿的各种类型石英为例,讨论了它们的一系列矿物学特征,为金矿的评价及成因的研究提供了一定的有用信息. 相似文献