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1.
GFAAS中理论原子化效率与原子化温度的关系的研究   总被引:3,自引:0,他引:3  
本文在有效地控制和消除基体干扰的基础上 ,探讨了Ag ,As,Au ,Bi,Cd ,Co ,Cr,Cu ,Fe ,Ga,Hg ,Mn ,Mo ,Ni,Sb ,Pb和V元素的理论原子化效率与原子化温度的关系。研究表明 :元素的理论原子化效率是原子化温度的函数 ,在一定的原子化温度范围内 ,理论原子化效率与原子化温度呈线性递增关系 ,对研究的十八个元素其线性的相关系数在 0 994 0~ 0 9993之间 ,且斜率大部分在 0 0 6~ 0 0 7之间 ,说明在一定的原子化温度范围内 ,理论原子化效率随原子化温度变化的斜率是相近的。  相似文献   

2.
ICP-AES法测定广西中药白花丹不同部位常量及微量元素   总被引:2,自引:0,他引:2  
采用电感耦合等离子体发射光谱法(ICP-AES) 分析广西中药白花丹根、茎、叶3个部位的20种常量及微量元素。结果显示,白花丹中除了含人体必需的常量元素K,Ca,Na,Mg外, 还有Zn,Fe,Mn, Cr,Co等必需的微量元素和其他元素Mo, Sb,Bi,Cd, Sr,Pb,Cd,As等。各元素的含量在白花丹的根,茎,叶中分布不同, 在叶和根中的含量比较丰富,与白花丹的抗菌, 抗肿瘤及抗氧化活性的药用有效部位在根部和叶部的结果一致,如Na,K,Ca,Zn,Fe,Mn,Sr,Cu,Co等含量在叶中含量最高,根次之。在许多抗癌中药中,Zn,Mn,Fe的含量通常比较高,Cr,Sr,Cu的含量也至关重要,作为传统抗癌中药的白花丹中就含有丰富的Zn,Mn,Fe和一定量的Sr,Cr,Cu元素,测定结果为探讨中草药中常量、微量元素与生物活性之间的相互协同关系提供了有用的数据,也为更好地开发和利用白花丹药用资源提供理论依据。  相似文献   

3.
声学消息     
恰好四十年前,Zwikker,Kosten的经典著作“Sound Absorbing Materials”出版(有中译本,席维克、柯斯汀《吸声材料》,科学出版社)奠定吸声材料的理论基础,Mechel的专著“Schallabsorber”是一个重大发展。书分三卷,卷一,外声场,即声场与吸声体的相互作用;卷二,内声场,即吸声体的构造,应用;卷三,计算程序,是辅助材料,现在出版的是卷一。本卷有十四章,1.引言,2.文献,3.声场基础;4.声场与吸声体相互作用,5.吸声带的吸收,6.柱形吸声体,7.吸收球,8.无穷平面吸声体,9.辐射阻抗,10.声场激发的表面辐射阻抗,11.表面波,  相似文献   

4.
影响南丰蜜桔品质的土壤元素ICP-MS/ICP-AES分析   总被引:1,自引:0,他引:1  
南丰蜜桔是原产于江西南丰的优良品种,但是品质随着种植地区的不同差异较大。文章借助ICP-MS/ICP-AES技术对江西6个不同地区,生产南丰蜜桔品质的土壤中植物的必需元素进行了分析,以期找到影响南丰蜜桔品质的土壤因素。结果显示, 品质较好的3个地区土壤中B, P, K, Mg和Ca含量均高于品质较差地区的含量,特别是B, P和K含量差异显著,而Fe, Mn, Si, Cu和Zn含量则低于品质差的地区。上述结果表明南丰蜜桔的品质主要受B, P, K, Mg和Ca控制,尤其是B, P, K影响较大;而Fe, Mn, Si, Cu和Zn对南丰蜜桔品质影响较小。所以在种植南丰蜜桔时应当适当增加B, P, K, Mg和Ca等肥料的施用量。  相似文献   

5.
物理学中表述"非真"意思的专有形容词有quasi,pseuclo,virtual,imaginary,false等,此外时常用到的还包括counterfeit,fake,fraudulent,feint,spurious,等等.用这些词构造的物理学名词随处可见,难以计数,真假难辩的境界里尤其考验学习者的分辨能力.  相似文献   

6.
制备了La,Ce,Nd,Sm,Eu,Gd,Dy微粒和纳米金,分别用La,Ce,Nd,Sm,Eu,Gd,Dy微粒替代部分的纳米金,研究了La-Au,Ce-Au,Nd-Au,Sm-Au,Eu-Au,Gd-Au,Dy-Au微粒分别对银染效果的影响及其紫外可见(UV-Vis)吸收光谱。与纳米金相比,La-Au,Ce-Au,Nd-Au,Sm-Au,Eu-Au,Gd-Au,Dy-Au微粒可延长银染后的斑点持续的时间,其中Nd-Au微粒的效果最好,斑点持续的时间为30 min,是纳米金的2.7倍;可大幅度加深斑点的颜色,其中Nd-Au,Sm-Au微粒的效果最好,用Nd微粒替代部分的纳米金,纳米金用量降低了80%,但还能提高银染法的灵敏度。在200~800 nm范围,La,Ce,Nd,Sm,Eu,Gd,Dy微粒和纳米金溶液的UV-Vis吸收光谱只有一个吸收峰,λmax分别为275,277,276,276,278,277,278和521 nm;La-Au,Ce-Au,Nd-Au,Sm-Au,Eu-Au,Gd-Au,Dy-Au微粒混合液的UV-Vis吸收光谱有两个吸收峰,λmax(RE)λmax(Au)分别为276和522 nm,276和522 nm,276和523 nm,276和523 nm,276和522 nm,276和522 nm,276和523 nm,纳米金和La微粒的吸收峰的波长发生了红移,Ce,Eu,Gd,Dy微粒的吸收峰的波长发生了蓝移,Nd,Sm微粒的吸收峰的波长不变,纳米金与稀土微粒可能有相互作用。  相似文献   

7.
磁化溶液样品对ICP发射光谱的增敏效应   总被引:2,自引:0,他引:2  
利用磁感应强度为0.24T的磁场处理含乙醇的水溶液,研究了样品溶液的物理性质和雾化特性以及样品溶液中元素的谱线强度随磁化时间的变化情况,并且讨论了磁化机理。实验结果表明,随着磁处理时间的延长,分析样品的有效利用率提高了;当样品中加入乙醇时,元素的谱线强度较早地出现了峰值。在磁化时间为2 h的条件下,不含乙醇的样品溶液中,元素Zn, Pb, Cd, Fe, Si, Cu, Cr和Sr的谱线强度比溶液未磁化时分别提高了22.9%, 38.8%, 25.6%, 48.3%, 52.4%, 6.0%, 22.3%和22.7%;含6%乙醇的样品溶液中,元素Zn, Pb, Cd, Fe, Si, Cu, Cr和Sr的谱线强度比溶液未磁化时分别增加了22.4%, 42.6%, 39.4%, 43.9%, 72.4%, 9.7%, 16.1%和17.1%。样品溶液磁化后进行分析, 有利于降低光谱分析检出限。  相似文献   

8.
黄飞  张宗烨  余友文 《中国物理 C》2005,29(10):948-953
在手征,SU(3),夸克模型中,通过求解共振群方程动力学地研究了同位旋,I=1/2,和,I=3/2,道,Nπ,的,S,波和,P,波低能弹性散射相移.所用的模型参数由基态八重态和十重态重子的能量定出, 并能给出不同分波的,KN,散射相移.除了有明显共振态的道以外, 计算得到的各个分波的,Nπ,散射相移和实验值定性一致.  相似文献   

9.
ψ'→J/ψ π+π-,提供了一个抽取低于,0.59GeV,的,ππ S,波相移的新途径.基于在树图衰变振幅中忽略,D,波的近似, 给出了从,ψ'→J/ψ π+π-,的\,ππ,不变质量谱中得到,ππ S,波相移的公式.  相似文献   

10.
用硝酸、高氯酸和氢氟酸溶解样品,在0.025 mol·L-1 EDTA介质中,采用一种标准溶液,用ICP-AES光谱法测定样品溶液中Ni,Cu,V,Mn,W,Mo,Co,Cr的含量。研究了基体和共存元素对分析元素光谱的影响,选择合适的波长,测定了分析结果的精密度,方法的检出限和回收率,结果表明,分析方法有很低的检出限,样品分析结果的相对标准偏差小于1%,加入回收率在98.2%~101.6%,方法准确、可靠、简便、快速,满足生产要求。  相似文献   

11.
ABSTRACT

This study computes the potential energy curves of the X1Σ+, A1Π, B1Δ, C1Σ+, and D1Π states of AlO+ cation and the transition dipole moments between them. The orders of the rotationless radiative lifetimes are 10–100?μs for the A1Π state, 1–1000?ms for the B1Δ state, 10?ns for the first well and 100?ns for the second well of the C1Σ+ state, and 1?μs for the D1Π state. Emissions of the B1Δ–A1Π and D1Π–C1Σ+ systems are so weak that they are hardly measured via spectroscopy, the emissions of the C1Σ+–X1Σ+, C1Σ+–A1Π, and D1Π–X1Σ+ systems are so strong that they can be detected readily, and emissions of the A1Π–X1Σ+ and D1Π–A1Π systems can be observed through spectroscopy only by a significant effort. There is a strong great similarity between spontaneous emissions of the A1Π–X1Σ+ system of the AlO+ cation and the A2Π–X2Σ+ system of the AlO radical. The emissions of the A2Π–X2Σ+ system of the AlO radical have been measured in outer space Therefore, it is highly possible that the emissions of the A1Π–X1Σ+ system of the AlO+ cation can be detected in the astrophysical media.  相似文献   

12.
The assignment of the high resolution Fourier transform spectra of carbon dioxide enriched in 17O and 18O which were recorded in LADIR (Paris, France) with the Bruker IFS 125-HR between 1800 and 9000 cm?1 and in USTC (Hefei, China) with the Bruker IFS 120-HR between 1700 and 9000 cm?1 was performed. In total 239 bands of 12 isotopologues: 16O12C16O, 16O12C18O, 16O13C16O, 16O13C18O, 18O12C18O, 18O13C18O, 16O12C17O, 17O12C17O, 17O12C18O, 16O13C17O, 17O13C17O and 17O13C18O were observed. Among them, 99 bands were observed for the first time. The majority of new observed bands belong to 17OCO isotopologues. The positions of 23,003 lines were determined with the experimental uncertainty on the level of 0.001 cm?1. The spectroscopic constants were fitted to the observed line positions for all observed bands.  相似文献   

13.
Quantum-mechanical calculations of the potential curves of the HeO+ ion are preformed which correlate with four lower dissociation limits and indicate the excimer type of the ion. The transition dipole moments of the 22Σ?→12Σ? and 24Σ?→14Σ ? transitions are calculated. The energies and radiative lifetimes of vibrational levels are determined and structural and spectroscopic constants of the states 12Σ?, 22Σ?, 14Σ?, and 24Σ? are calculated. The fluorescence spectrum corresponding to the 22Σ?→12Σ? and 24Σ?→14Σ ? transitions is also calculated. The possibility of lasing at these transitions is discussed.  相似文献   

14.
The complete infrared spectrum of gaseous NSCl, including the hitherto unobserved ν3, is reported. A set of force constants for gaseous NSCl consistent with a number of pieces of independent data such as the isotopic shifts (14N32S35Cl, 15N32S35Cl, 14N32S37Cl, 15N32S37Cl, 14N34S35Cl and 15N34S35Cl), centrifugal distortion constants (14N32S35Cl), and the inertia defect (14N32S35Cl) has been computed. Also, the force field of NSF has been redetermined using the vibrational frequencies and the centrifugal distortion constants.  相似文献   

15.
The data on the excitation functions of20Ne(16O,12C)24Mg,20Ne(16O,12C)24Mg*(1.37, 2+),20Ne(16O,12C)24Mg*(4.12, 4++4.24, 2+) +20Ne(16O,12C*(4.44, 2+))24Mg,20Ne(16O,12C)24Mg*(6.01, 4++6.43, 0+),20Ne(16O,20Ne)16O,20Ne(16O,20Ne*(1.63, 2+))16O, and20Ne(16O,20Ne*(4.25, 4+))16O reactions atθ lab=13° fromE c.m.=22.8 to 38.6 MeV have been subjected to a statistical analysis comprising of the calculations of the distribution of cross sections, deviation functions, cross-correlation functions, summed excitation functions, cross-channel correlation coefficients and coherence widths. The analysis confirms the existence of nonstatistical structures atE c.m.=24.6, 27.8, 31.7 and 35.5 MeV, and identifies a new structure of the same nature atE c.m. =25.6 MeV.  相似文献   

16.
We present a continuation of our investigation of the second most abundant isotopic species of nitrous oxide, 14N15N16O and 15N14N16O, in the infrared (IR). Our two previous contributions looked at the 3500–9000 cm−1 region for 14N15N16O and 15N14N16O, respectively, in the 3500–9000 cm−1 region. The use of highly enriched isotopologue samples in this study allowed us to go further into the IR, down to 1200 cm−1. A total of 2 2742 transitions have been assigned based on the effective Hamiltonian model, with 108 of them being reported here for the first time. Rovibrational analyses of 98, 101, 8, 3, 6, 1 and 1 bands for the 14N15N16O, 15N14N16O, 15N15N16O, 14N15N18O, 15N14N18O, 14N15N17O and 15N14N17O isotopologues, respectively, were also performed.  相似文献   

17.
The temperature dependence of the rates of 113Cd →113In, 115In →115Sn, 92Zr→92Nb →92Mo, 94Zr→94Nb →94Mo, 96Mo →96Tc→96Ru, and 98Mo→98Tc→98Ru thermal beta transitions was studied at temperatures of massive-star matter in the range of 1 × 108–6 × 109 K. These decays are the possible channel of synthesis of the p nuclei of 113In, 115Sn, 92,94Mo, and 96,98Ru. The abundances of these nuclei present a challenge for models that study the explosivemechanism of synthesis. The contribution of photobeta decay to the synthesis of the aforementioned p nuclei was estimated. It was shown that the channel of thermal beta decay for 113In, 115Sn, 94Mo, and 98Ru p nuclei and the channel of photobeta decay for the 96Mo p nucleus could be efficient at the high-temperature quasiequilibrium stage of massive-star evolution.  相似文献   

18.
The data on the excitation functions of24Mg+24Mg elastic and inelastic (24Mg +24Mg*(2+),24Mg*(2+)+24Mg*(2+),24Mg+24Mg*(4+),24Mg*(4+)+24Mg*(2+),24Mg+24Mg*(6+)) scattering fromE c.m=42 to 56 MeV have been subjected to a statistical analysis consisting of calculations of deviation function, cross-correlation function, cross-channel correlation coefficients, coherence widths, and the distribution of cross sections. On the basis of the analysis resonant structures atE c.m=45.70, 46.65, 47.35 and 47.75 MeV have been confirmed. Two new resonant structures atE c.m=44.55 and 50.50 MeV have been identified.  相似文献   

19.
The proof is given for the existence of the reaction e+e → h±h? in the energy range 1400–2400 MeV, and its energy dependence is compared with that of e+e → e±e?, in the same experimental conditions of observation. The exponent of the s-dependence of the ratio α = (e+e → h±h?)/ (e+e → e±e?) is measured to be n = 2.08 ± 0.45, in the s-range (1.96 − 5.76) GeV2, on the basis of 51 e+e → h±h? events and 8918 e+e → e±e? events observed.  相似文献   

20.
We present a summary of precision atomic mass measurements of stable isotopes carried out at Florida State University. These include the alkalis 6Li, 23Na, 39,41K, 85,87Rb, 133Cs; the rare gas isotopes 84,86Kr and 129,130,132,136Xe; 17,18O, 19F, 28Si, 31P, 32S; and various isotope pairs of importance to neutrino physics, namely 74,76Se/74,76Ge, 130Xe/130Te, and 115In/115Sn. We also summarize our Penning trap measurements of the dipole moments of PH?+? and HCO?+?.  相似文献   

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