ARTIFICIAL NEURAL NETWORK IN MOSSBAUER SPECTROSCOPY

ＡＲＴＩＦＩＣＩＡＬ　ＮＥＵＲＡＬ　ＮＥＴＷＯＲＫ　ＩＮ　ＭＯＳＳＢＡＵＥＲ　ＳＰＥＣＴＲＯＳＣＯＰＹＮｉＸｉｎｌｅｉａｎｄＨｓｉａＹｕａｎｆｕ（ＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃｓ，ＮａｎｊｉｎｇＵｎｉｖｅｒｓｉｔｙ，Ｎａｎｊｉｎｇ２１０００８，...     

ITALIAN MONEY TESTED FOR FORGERY BY MOSSBAUER SPECTROSCOPY

Italian money has been investigated by Mossbauer spectroscopy. The results indicated that the spectrum of a 10000 lire bank-note consisted of three magnetic sextets and two quadrupole doublets, the spectrum of a 50000 lire note consisted of two Zeeman sextets, but in the "false" money there are two quadrupole doublets only.     

TRACKING PYRITIC SULFUR DURING THE MICROWAVE- CHEMICAL DESULFURIZATION OF COAL USING MOSSBAUER SPECTROSCOPY

The transformations of pyrite in coal during the microwave-chemical treatment for desulfurization of coal was studied with Mossbauer spectroscopy of Fe. The results for phase analyses show that the selective dielectric heating by microwave energy can give rise to the thermal decomposition of pyrite FeS2 in coal to new phases, pyrrhotite Fe1-xS (0相似文献   

STUDY ON Fe ION DISTRIBUTION IN NATURAL CHROMITE BY MOSSBAUER TECHNIQUE

Mossbauer absorption spectra in a natural chromite from Shanxi province of China were measured, covering a temperature range from 12 K to 800 K. Each spectrum at low temperature can be fitted to three doublets: the first two are attributed to tetrahedral T-site Fe ions and the third one to octahedral M-site Fe ions. Such assignment was confirmed by the detailed analyses of the temperature dependent centre shift and other parameters. As a main result, our data strongly supported the ordered distribution with Fe2+ in T-site and Fe3+ in M-site for chromite studied. No evidence for electron hopping processes was detected.     

一种应用穆斯堡尔谱学进行定量物相分析的方法

提出了应用穆斯堡尔谱学进行定量物相分析的新方法，该法具有实验简便、快速、数据处理简单和实验结果准确等优点。     

MOSSBAUER SPECTROSCOPY OF HIGH T_c YBa_2 (Cu_(3-x)Fe_x )O_y

ＭＯＳＳＢＡＵＥＲＳＰＥＣＴＲＯＳＣＯＰＹＯＦＨＩＧＨＴ＿ｃＹＢａ＿２（Ｃｕ＿（３－ｘ）Ｆｅ＿ｘ）Ｏ＿ｙ￥ＬｉＳｈｉ（李士）ａｎｄＬｉＹｉｎｈｕａ（李印华）（ＩｎｓｔｉｔｕｔｅｏｆＨｉｇｈＥｎｅｒｇｙＰｈｙｓｉｃｓ，Ｂｅｉｊｉｎｇ１０００８０，Ｃｈｉ...     

A MOSSBAUER EFFECT STUDY ON Co DOPING IN SmTiFe_(11) COMPOUND

A series of SmTiFe11-xCox compounds where x ranges from zero to five, have been studied by Fe Mossbauer spectroscopy, X-ray diffraction and related magnetic measurements. The radom site occupation of Co atom in SmTiFe11-xCox was found when x≥1. The temperature dependence of the magnetic hyperfine field for SmTiFe11 and the Co concentration dependence of the magnetic hyperfine field for the samples, SmTiFe11-xCox are obtained. Also the Debye temperature of SmTiFe11 have been estimated from the experiments.     

MOSSBAUER SPECTROSCOPIC STUDY OF FIRED SHENQIU METEORITES

The Shenqiu meteorite was investigated by Mossbauer spectroscopy at room temperature, atomic absorption, X-ray diffraction and scanning electron microscopy. In order to determine fired conditions of the meteorite which occurred during the meteorite fall, Shenqiu meteorite samples were fired in an oxidizing atmosphere and a reducing atmosphere at temperatures up to 1300℃, respectively. These samples also were fired at 800, 1000 and 1200 ℃ respectively for different time (up to 24 h).     

MOSSBAUER STUDY OF CHINESE ANCIENT MINERAL DRUGS

About 100 crude Chinese mineral drug samples were investigated with M&'ssbauer spectroscopy, X-ray diffraction analysis and atomic absorption spectroscopy. The classifications, species and components of Chinese mineral drugs are elucidated. The pharmaceutic and curative mechanisms of these mineral drugs are discussed.     

MOSSBAUER POLARIMETER AND MOSSBAUER FARADAY EFFECT

A Mossbauer polarimeter consists of a gamma ray source (polarizer), transmitter (sample to be analyzed), analyzer and automatic counting system. This equipment was used to observe the Mossbauer Faraday effect in non-stoichiometric Fe3O4. Experimental results demonstrated that electronic hopping above the Verwey temperature between Fe2+- Fe3+ ions on the octahedral sites is a only localized phenomenon and the recoilless fractions of 57Fe nuclei in Fe3-vO4 (v=0.02) are 0.71 for A sites and 0.62 for B sites, respectively.     

MOSSBAUER ANALYSIS ON THE MICROWAVE—MAGNETIC DESULFURIZATION OF RAW COAL

The selective dielectric heating of microwave energy to convert a portion of each pyrite particle to moderately magnetic pyrrhotite has been suggested to enhance the magnetic separation of inorganic sulfur from coal.The results for Mossbauer analyses show that the considerable amount of pyrrhotite produced during microwave irradiation,carrying with it some of non-magnetic pyrite(unconverted),ferrous sulfate,and troilite,is completely removed from coal after magnetic separation.The optimum desulfurization efficiency can be attained by appropriately controlling the irradiation time to maximize the amount of pyrrhotite formed pyrite decomposition.Excessive irradiation would be ddisadvantageous for improving magnetic separation due to the further decomposition of pyrrhotite to antiferromagnetic troilite.     

MOSSBAUER STUDIES OF MAGNETIC ANISOTROPY OF AMORPHOUS Fe-(Co, Cr)-Zr ALLOYS

Magnetic anisotropies and hyperfine fields of amorphous a-Fe-(Co, Cr)-Zr alloys, their temperature and thermal stress effects were studied by using a Mossbauer spectroscopy. The results are in the following: A tensile stress field is easily created during the material production process, having the plane anisotropy to be increased for the alloys containing strong ferromagnetic coupling such as Fe-Co and Fe-Ni; a pressure stress field is easily produced, making the perpendicular anisotropy increase for the alloys containing antiferromagnetic coupling such as Fe-Cr and Fe-Mn. Introducing the new idea of attractive and repulsive forces, the fact was explained well that the dependence of anisotropies on the average outer electron concentration of 3d transition metal is similar to that of the average hyperfine field.     

MOSSBAUER STUDY ON REDUCIBILITY OF SUPPORTED Eu_2O_3

ＭＯＳＳＢＡＵＥＲＳＴＵＤＹＯＮＲＥＤＵＣＩＢＩＬＩＴＹＯＦＳＵＰＰＯＲＴＥＤＥｕ_２Ｏ_３ＷｕＸｉａｏｈｕａ，ＨｓｉａＹｕａｎｆｕ，Ｈ．Ｍ．Ｗｉｄａｔａｌｌａｈ~１（ＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃｓ，ＮａｎｊｉｎｇＵｎｉｖｅｒｓｉｔｙ，Ｎａｎｊ?..     

氧化物玻璃中短程有序的穆斯堡尔诺学研究

在以往对氧化物玻璃的穆斯堡尔研究中,通常将谱线按分立的洛仑兹线拟合。然而在玻璃中,由于电场梯度的分布,引起可观的谱线加宽 在本工作中我们用Hesse-Rubartshch法计算四极分裂的总分布,再将所得的分布曲线以高斯线型进行亚谱线拟合,分别给出四面体配位和八面体配位的贡献。所得到的平均四极裂距Δ和分布宽度σ_Δ分别对应于铁离子周围的环境对称性和位置相似性,从而用所得四极分裂分布可以量度玻璃中的短程有序。依据Brodbeck-Bukrey模型,再由四极分裂的分布导出铁离子周围环境的畸变参量的分布,由此得出关于玻璃中短程有序的更详细的定量数据。     

单线的~(57)Co穆斯堡尔源的制作

穆斯堡尔谱学的发展,希望能获得更理想的穆斯堡尔源。本文报道了为穆斯堡尔实验制作这种源的程序:首先生产出纯度高的~(57)Co,配成电镀液,待~(57)Co沉积在源基体上后,经热扩散后测试所作源的各个参量。     

MOSSBAUER STUDIES OF HEMOGLOBIN AND THE IMMUNE FUNCTION OF RBC OF THE PATIENTS WITH HEPATIC DISEASES

Red blood cells (RBC) of the patients with cirrhosis and with primary liver cancer were studied by using Mossbauer spectroscopy. The measurements of RBC from normal adults were made as control. Results showed that the subspectrum representing deoxy-Hb either disappeared or diminished, but no other subspectrum was detected in the samples from the patients. In addition, the immune function of RBC of these two types of patients was measured by using immune-adherence haemagglutination (IAHA), which indicated that its immune function was significantly lower than that of normal adults (P<0.01). These experimental results showed that the components of hemoglobin in RBC are correlated with the immune function of RBC.     

六核铁硫笼状原子簇化合物的穆斯堡尔谱研究

实验测定了六核铁硫笼状原子簇化合物(α)Fe_6S_5(PEt_3)_4(SR)_2和(b)Fe_6S_5(μ-Sph)(PB_(u3)~n)_4(SPh)_2的穆斯堡尔谱。它们都是由两组对称的四极分裂双峰叠加而成.实验数据用最小二乘法计算程序拟合。拟合后的穆斯堡尔参数(在77K时):对于簇合物(α),Fe_1的δ=0.458±0.004mm/s,△E_Q=0.805±0.004mm/s,A=63.0±3％;Fe_Ⅱ的δ=0.286±0.004mm/s,△E_Q=0.849±0.004mm/s,A=37.0±3％;对于簇合物(b),Fe_Ⅰ的δ=0.529±0.004mm/s,△E_Q=0.782±0.004mm/s,A=68.2±3％;Fe_Ⅱ的δ=0.335±0.004mm/s,△E_Q=0.781±0.004mm/s,A=31.8±3％.它们的δ值是相对于α-Fe的。利用四面体FeS_4中铁原子的化学位移δ与价态s的经验公式δ=1.44-0.43s可得出:簇合物(α)的Fe_Ⅰ平均价态为+2.2价,Fe_Ⅱ的平均价态为+2.6价;簇合物(b)的Fe_Ⅰ价态为+2价,Fe_Ⅱ的平均价态为+2.5价。     

穆斯堡尔谱学现状

穆斯堡尔谱学已成为了解原子核与其周围环境间超精细相互作用的重要方法。本文介绍了穆斯堡尔谱学方法的特点及近年来在方法学和应用方面的进展。最后展望了穆斯堡尔谱学的将来。     

在穆斯堡尔谱学方面计算机的应用

本文概述了计算机在穆斯堡尔谱学方面新的应用。包括用计算机硬件构成各种计算机化穆谱仪;以及采用多种软件为拟合、解谱、对比、校准等手段提供数据处理的各种方法。预期这两方面的应用都会有较快的发展,必将进一步促进穆斯堡尔谱学的研究工作。