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在pH4.0的HAc-NaAc介质中,Pb(Ⅱ)与1-苯基-3-基-4-苯甲酰基-吡啉酮-5(PMBN)生成络合物,于一0.56V(vs.SCE)处出现一尖锐、灵敏的极谱峰。Pb浓度在4.83×l0 ̄-9~1.69×10 ̄-6mol/L与峰高呈线性关系。用多种电化学方法研究了极谱波的性质及反应机理,证明-0.56V处的极谱波为络合物吸附波,峰电流由中心离子Pb(Ⅲ)还原产生。用直线法测得络合物组成比为l:l。试验了30多种离子对峰电流的影响。方法已用于矿石中痕量pb的测定。 相似文献
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痕量银与meso-四(对-磺酸基苯基)卟啉显色反应的研究 总被引:4,自引:0,他引:4
研究了Ag(I)与meso-四(对-磺酸基苯基)叶琳的光催化显色反应。在pHl0的缓冲溶液中形成稳定的Ag(I)-TPPS_4-CTMAB三元配合物,其最大吸收波长为426nm,组成为Ag(1)TPPS_4:CTMAB=1:1:2。表观摩尔吸光系数为2.79×l0 ̄5L·mol ̄-1·cm ̄-1,Ag(1)的浓度在0~0.2μg/ml内符合比尔定律。基于此建立的测Ag(I)方法灵敏度高,结合巯基棉分离干扰,可用于矿物中Ag(I)的测定。 相似文献
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常温下在pH4的HAc-NaAc缓冲体系中,Ga与1,5-二(2-羟基-5-磺基苯基)-3-氰基甲 (DSPCF)形成稳定的蓝色配合物。该配合物在波长630nm处有最大吸收,其表观摩尔吸光系数为3.8×10 ̄4L·mol ̄-1·cm ̄-1,配合比为n(Ga):n(DSPCF)=1:2,显色反应在20min内完成,稳定时间至少24h,Ga量在0~1.8mg/L时遵守比尔定律。采用TBP萃淋树脂分离干扰元素后可实现煤矸石中Ga的测定。 相似文献
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研究了新试剂2,4-二溴-6-羧基苯重氮氨基偶氮苯与Tl(Ⅲ)的高灵敏显色反应。在非离子表面活性剂TritonX-100存在下,于pH10.5的NH_3·H_2O-NH_4Cl缓冲介质中,Tl(Ⅲ’)与该试剂生成红色配合物,其配合物的最大吸收波长位于520nm处,摩尔吸光系数为1.83×10 ̄5L·mol ̄-1·cm ̄-1。Tl(Ⅲ’)量在0~0.64μg/ml范围内符合比尔定律。方法用于废水中痕量Tl的测定,结果与其它方法结果相符。测定工业废水及粉煤灰中痕量Tl的RSD(n=6)在1.6%~3.2%范围。 相似文献
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钪-对氟偶氮氯膦-TritonX-100显色反应及其应用 总被引:1,自引:0,他引:1
当TritonX-100存在时,Sc与对氟偶氮氯膦(CPA-pF)在常温下反应形成p型络合物,表现摩尔吸光系数为6.I×I0 ̄4L·mol ̄-1·cm ̄-1,TritonX-100可提高络合物的稳定性使之至少稳定24h,Sc(Ⅲ)浓度在0.0~0.μg/ml符合比尔定律。方法可用于合金中痕量Sc的测定。 相似文献
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研究结果表明,在混合表面活性剂CTMAB-吐温-60存在下的pH5.7~6.5的缓冲介质中,Sc(Ⅲ)与4,5-二溴苯基荧光酮(DBPF)形成高灵敏的多元配合物,其ε_(590)=2.26×10 ̄5L·mol ̄(-1)·cm ̄(-1),组成比为:Sc:DBPF:CTMAB=1:2:4。采用混合表面活性剂使增溶增敏作用更为显著,并加速了显色反应,增强了配合物的稳定性。而Na_2SO_4的加入能显著地提高体系的灵敏度。Sc量在0~0.36ug/ml范围内遵守比尔定律。方法可直接测定合成混合稀土中的Sc,回收率在98%~105%;结合沉淀分离和PMBP萃取分离,实现了地质试样中痕量Sc的测定。 相似文献
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在0.18~0.32mol/LHCl介质中,Mo(Ⅵ)与3,4-二甲氧基苯基荧光酮(DMOPF)和Tween-80形成三元胶束配合物,最大吸收峰在526nm处,摩尔吸光系数为1.16×10 ̄5L·mol ̄-1·cm ̄-1,Mo(Ⅵ)含量在0~0.53μg/ml范围内符合比耳定律。所建立的方法用于矿样中Mo的测定,结果较为满意。 相似文献
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本文合成了新试剂2,6-二氯-4-硝基苯氨基重复偶氮苯(DCNAD)。研究了在吐温80存在下DCNAD与Cu(Ⅱ)的显色反应,结果表明在pH为10.0~10.8内cu(Ⅱ)与DCNAD形成稳定的1:2配合钧,其最大吸收峰位于590nm,摩尔吸光系数为1.9×10 ̄51.mol ̄(-1).cm ̄(-1),Cd(Ⅱ)的量在0~0.9μg/ml内符合比耳定律。以氟化钠-酒石酸钾钠-硫脲为掩蔽剂,方法具有较高的选择性,用于水样中微量镉的测定,获得了较好的结果。 相似文献
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Ivan V. BRAGIN Georgy A. CHELNOKOV Oleg V. CHUDAEV Natalia A. KHARITONOVA Sergey V. VYSOTSKIY 《《地质学报》英文版》2016,90(1):276-284
Studied waters belong to warm(T=30-50℃),alkaline(pH=8.9-9.3),low mineralized(TDS235 mg/1)Na-HCO_3 or Na-SO_4-HCO_3 thermal waters with high content of SiO_2(up to 81 mg/l)and F(up to 3.9 mg/1),occur on modern volcano-tectonic rejuvenated areas of Eastern Sikhote-Alin orogenic belt.Low~3He concentration as well as N_2/O_2 and N_2/Ar ratios exclude influence of deep mantle fluid.New rare earth element data constrain our understandmg of water-rock interaction occurring in the water source region.Meteoric origin of waters is proved by stable isotope values varying from-71‰to-136.1‰and from-10.8‰to-18.8‰forδ~2U andδ~(18)O respectively.REE patterns reflect high pH,resultfing from water-rock interaction and oxidative conditions.Calculations of deep aquifer temperature using Na-K and quartz geothermometers show 116.8-131.1°C and 82.2-125.8℃respectively.Presence of deep faults both with abnormal thermal gradient(~45-50 K/km)define unique geochemical shape of thermal waters of Sikhote-Alin,area,where no present volcanic activity is registered. 相似文献
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沉管隧道基槽爆破施工对既有堤岸稳定性影响的数值仿真分析 总被引:1,自引:0,他引:1
结合爆破数值模拟中爆破荷载的特点,分析了各种荷载施加方法的特点及爆破震动场模拟的要求,基于圣维南荷载等效原理,提出了爆破荷载的等效施加方法,即将作用在炮孔壁上的爆破荷载等效后,施加在同排炮孔中心线或者面上来模拟爆破荷载的作用。结果表明,等效施加方法在近区存在一定差异,但在中远区吻合得较好。利用该等效荷载施加方法,采用三维实体模型计算分析了某沉管隧道基槽爆破施工对既有堤岸稳定性影响,计算了周围不同位置、不同深度位置处的振动响应,并在此基础上,分析研究了减小爆破振动对既有结构物影响的减振措施,可为类似工程提供借鉴。 相似文献
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考虑核电厂地基-基础的动力相互作用,应用显式动力有限差分法分析了地震作用下极软岩、较软岩、坚硬岩上核电厂建筑结构基础的地震响应特征,比较了岩石坚硬程度对基础加速度反应谱的影响。研究表明:随着岩石坚硬程度的提高,核电厂建筑物结构基础的地震响应有增加的趋势;在周期轴上,基础处的加速度反应谱曲线会随着岩石坚硬程度的提高逐渐向短周期(高频段)方向移动。在高频段,建造于较坚硬岩石上基础结构的加速度反应谱值偏大;在中等频段,建造于较软岩石上基础结构的加速度反应谱值偏大;在低频段,岩石坚硬程度对加速度反应谱的影响不显著。 相似文献
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M. D. Sharma 《Journal of Earth System Science》2004,113(2):247-257
Three dimensional scattering of near-field is studied for dilatation and rotation in the time domain. The perturbation method
is applied to solve the equation of motion for the first order scattering from a weak inhomogeneity in an otherwise homogeneous
medium. The inhomogeneity is assumed close enough to the point source so that the near-field intermediate wave is dominating
over the far-field sphericalP andS pulses. The integral expressions are derived to relate dilatation and rotation of scattering to the radial fluctuations of
velocities and density in the inhomogeneity. These integrals are solved to calculate the strains of scattering from (a part
of) an inhomogeneous spherical shell of arbitrary curvature. Variable curvature may allow the shape of inhomogeneity volume
element to change uniformly from spherical to rectangular. Rotation of scattering from a spherical shell is independent ofP wave velocity inhomogeneity. Dilatation of scattering does not involveS wave velocity inhomogeneity but its gradient. The back scattering results are obtained as a special case. Strains are computed
numerically, for hypothetical models to study the effects of various parameters viz., velocity inhomogeneity, distance of
source from inhomogeneity and from receiver, and thickness of inhomogeneity. The curvature of the spherical shell is varied
to study the effects of the shape of inhomogeneous volume element on scattering. 相似文献
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A. Anandarajah 《Engineering Geology》1997,47(4):491-323
In an assembly of clay particles placed in a fluid, each particle is typically subjected to: (1) double-layer repulsive forces; (2) van der Waals attractive forces; and (3) contact mechanical forces. The study presented here concerns an approximate, quantitative analysis of clay suspensions, with considerations to the first two - the physico-chemical forces. Using recent theories to calculate the physico-chemical forces between two clay particles in an approximate model of an assembly, the equilibrium void ratio of a clay suspension is computed. The mechanical forces are ignored in the analysis. The results serve to verify the validity of physico-chemical theories employed and help interpret experimental data more fundamentally in terms of the system variables. 相似文献
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