火焰原子吸收法测定大洋底锰结核中的铜,钴,镍,铁,锰

本文介绍了用火焰原子吸收法对大洋底锰结核中铜，镍，铁、锰中五种离子同时测定的方法。确定了仪器工作条件，并对共存元素及残留试剂的影响进行了研究。方法精密度和准确度令人满意。     

基于光谱识别技术的土壤铁锰结核对镉的吸附行为研究

铁锰结核是具有高反应活性的矿物复合体;与海洋铁锰结核不同,土壤铁锰结核常在干湿交替、水气干扰条件下存在,形成了独具特色的地球化学特征.作为土壤"新生体",不同地区铁锰结核常表现出较大差异.研究典型区域土壤铁锰结核与重金属的结合行为,有助于深入了解铁锰结核的微生态属性,对于后续土壤的开发利用、保育改良、污染修复等都具有战...     

植物超声提取物抗氧化成分的光谱分析比较

用超声法提取了杭白菊、柚皮和豆渣中的总抗氧化成分。通过紫外(UV)分析,比较了三种提取物的抗氧化能力的大小;通过红外光谱(FT-IR)分析,初步推断了三者的抗氧化物质的主要成分为羰基化合物及酚羟基化合物。     

一种新的线性神经网络多组分分析法及其在VC银翘片NIR定量分析中的应用

用红外光谱仪测量了VC银翘片的近红外谱图,然后将主成分分析法(PCA)和线性神经网络结合,分析VC银翘片中的对乙酰氨基酚和维生素C的含量。讨论了主成分数的选择及影响神经网络的各参数。为了比较算法的性能,作者又分别采用了偏最小二乘法、主成分分析结合BP神经网络进行数据处理。实验及数据处理结果表明,在3种多组分分析方法中,主成分分析结合线性神经网络的方法具有最高的预测精度。     

硅基籽晶上化学气相沉积金刚石薄膜及其场发射特性

通过控制电泳沉积(EPD)时间,在硅基片上沉积不同密度的金刚石籽晶。再用热丝化学气相沉积(HFCVD)设备,在硅基籽晶上合成多晶金刚石薄膜。薄膜中通常含有非金刚石相碳成分。用扫描电子显微镜(SEM)和Raman光谱对样品的表面形貌和成分进行了表征,测量了样品的场发射特性。比较并分析了样品的表面形貌和非金刚石成分上的差异对金刚石薄膜场发射特性的影响。     

热电子,双离子成分对离子漂移回旋不稳定性的影响

分析了热电子、温离子成分对离子漂移回旋不稳定性的影响，给出了临界稳定热电子成分值α与温离子成分值班出子温度比和离子抗磁漂移速度的关系；讨论了热电子、温、冷离子成分对不稳定性各谐频分支的影响；分析了热电子成分稳定作用的物理机制。     

微束X射线荧光光谱分析红土中铁锰结核内部微小区域

在中国南方第四纪红土剖面中普遍发育一种黑褐色,形状规则或者不规则的新生体,由于其含有较高的Fe和Mn元素而被称为铁锰结核。铁锰结核被认为是土壤中温度、水分、氧化还原条件变化而形成的土壤新生体,因此它被认为是环境信息的良好载体。尤其是结核内部发育的环带状构造,被认识是结核形成过程气候干湿变化的结果。因此对结核内部微小区域的研究,有助与理解红土母质的风化过程以及结核的形成原因。X射线荧光光谱分析在20世纪80年代初已是一种成熟的分析方法,是实验室、现场分析主、次量和痕量元素的首选方法之一。运用帕纳科Zetium X射线荧光光谱仪的微小区域分析工具对铜陵第四纪红土中结核内部由核心至边缘的主量元素分布状况进行分析,结果表明,XRF微小区域分析功能可以快速有效的分析样品内元素的分布状况。结核内部元素分布情况来看,铜陵剖面内铁锰结核内部颜色深浅变化主要是由于Mn元素含量的变化而引起的。结核的核心Mn元素含量最高,由核心向边缘呈现高低交替变化特征。指示结核形成初期,由于气候相对干旱,Mn元素由低价离子态氧化成高价化合物后发生淀积。结核内部浅色环带Si和Al元素含量明显较深色环带高,可能代表了相对湿润的气候时期。     

含轻元素二元合金成分的无标样X光能谱定量分析

本文对利用试样中不同元素X光强度相对比值分析成分的无标样定量分析方法提出了改进。首先对电子散射的“完全扩散”模型进行适当的修正和简化,得到标识X光的台阶状深度分布曲线,从而得到试样成分和标识X光强度的定量关系。对Cu-Si,FeS₂,NaCl和GaAs等二元合金的成分分析得到比较满意的结果。本文比较了用此法和Russ法(利用计算得到的纯元素标识X光强度因子并且经ZAF修正分析成分)得到的结果,表明用我们的方法分析的结果有所改善,计算程序也更简单。 关键词：     

微束X射线荧光光谱分析红土中铁锰结核内部微小区域（英文）

在中国南方第四纪红土剖面中普遍发育一种黑褐色,形状规则或者不规则的新生体,由于其含有较高的Fe和Mn元素而被称为铁锰结核。铁锰结核被认为是土壤中温度、水分、氧化还原条件变化而形成的土壤新生体,因此它被认为是环境信息的良好载体。尤其是结核内部发育的环带状构造,被认识是结核形成过程气候干湿变化的结果。因此对结核内部微小区域的研究,有助与理解红土母质的风化过程以及结核的形成原因。X射线荧光光谱分析在20世纪80年代初已是一种成熟的分析方法,是实验室、现场分析主、次量和痕量元素的首选方法之一。运用帕纳科Zetium X射线荧光光谱仪的微小区域分析工具对铜陵第四纪红土中结核内部由核心至边缘的主量元素分布状况进行分析,结果表明,XRF微小区域分析功能可以快速有效的分析样品内元素的分布状况。结核内部元素分布情况来看,铜陵剖面内铁锰结核内部颜色深浅变化主要是由于Mn元素含量的变化而引起的。结核的核心Mn元素含量最高,由核心向边缘呈现高低交替变化特征。指示结核形成初期,由于气候相对干旱,Mn元素由低价离子态氧化成高价化合物后发生淀积。结核内部浅色环带Si和Al元素含量明显较深色环带高,可能代表了相对湿润的气候时期。     

溶解有机物三维荧光光谱技术在赤潮藻识别中的应用

将赤潮藻生长过程中产生的荧光溶解有机物(fluorescent dissolved organic matter,FDOM)的三维荧光光谱与主成分分析相结合,尝试建立了我国沿海10种常见赤潮藻的识别测定技术.用主成分分析提取三维荧光光谱第一主成分载荷谱作为识别特征谱,建立了浮游植物荧光特征谱库,在此基础上利用Bayes...     

Mössbauer study on iron in marine sediments and manganese nodules

The chemical states of iron in a deep-sea sediment, a manganese nodule and a nearshore sediment are studied before and after chemical leaching. The Mössbauer spectra of the manganese nodule after chemical leaching clearly revealed the presence of a ferrous component not identified in previons studies. The ferrous component in the deep-sea sediment and the manganese nodule are shown to originate in terrigenous materials transported from lands through the atmosphere.     

X射线荧光光谱法测定烧结锰矿中的主次量成分

采用四硼酸锂和偏硼酸锂混合熔剂熔融法制样,X射线荧光光谱法测定了烧结锰矿中的MnO、Fe2O3、SiO2、Al2O3、TiO2、CaO、MgO、SO3和P2O59个主次量成分。以12个锰矿石标准样品建立校准曲线,用理论α系数法校正基体效应。测定烧结锰矿样品各成分的相对标准偏差(RSD,n=10)在0.26%—3.94%之间。用实际样品验证,测定结果与化学方法的测定值相符。与化学法相比,该方法具有快速、简便、精密度好和准确度高等优点。     

Boson peak, flickering noise, backscattering processes and radiative transfer in random media

The method of matrix Green’s functions in the classical theory of electromagnetic waves is stated. This method allows to obtain a closed equation system in the presence of the random media for the calculation both coherent, and incoherent (fluctuating) components of radiation. The density and heterogeneity of scattering media can be arbitrary. The coherent channel is calculated independently. The fluctuating radiation distribution in the medium is developed initially by an interference pattern generated by the coherent channel. The limitations of the processes speed are absent. The theory embraces such phenomena as the boson peak, flickering noise, memory effect, backscattering processes and also conventional radiative transfer equation and Fresnel’s formulae.     

Human response to vibration : Prepared by M. J. Griffin and J. Griffin,Human Factors Research Unit,Institute of Sound and Vibration Research,University of Southampton,Southampton SO9 5NH,England

In this paper an unified treatment is given to the problems of vibration characteristics of thin circular cylindrical shells with various end conditions with the aid of the kinematic relations of the first-order shell theory of Sanders. A simple variational technique is applied to give a cubic frequency equation. This cubic is reduced to two simple linear relations for the frequency parameter by incorporating an engineering approximation relating deflections in two different ways: (i) in general, (ii) in the inertia components only. It is shown that the linear formula obtained by (ii) is much superior to that obtained by (i) and also to the much more complicated cubic equation to some extent. Expressions for evaluating mode shapes are also given. Results found by using the present technique are compared with some previous exact analysis results. Frequencies calculated in the case of a given cylinder are shown to be in good agreement with some available observed results.     

Structural, spectral and mechanical studies of bimetallic crystal: cadmium manganese thiocyanate single crystals

A nonlinear optical bimetallic thiocyanate complex crystal, cadmium manganese thiocyanate (CMTC) has been successfully synthesized. The growth of single crystals of cadmium manganese thiocyanate has been accomplished from aqueous solution using slow evaporation method. The presence of manganese and cadmium in the synthesized material was confirmed through energy dispersive spectrum (EDS) analysis. Structural analysis was carried out using powder X-ray diffractometer (PXRD) and crystalline perfection of the grown crystals was ascertained by high-resolution X-ray diffraction (HRXRD) analysis. Fourier transform infrared (FTIR) spectrum was taken to confirm the functional groups. The transmittance spectrum of the crystal in the UV–visible region has been recorded and the cutoff wavelength has been determined. The dielectric measurements for the crystals were performed for various frequencies and temperatures. The mechanical properties were evaluated by Vickers microhardness testing, which reveals hardness and stiffness constant of the crystals.     

ICP-AES测定土壤中钡、铬和锰含量的不确定度评定

电感耦合等离子体-原子发射光谱法(ICP-AES)测定土壤中钡、铬和锰含量的不确定度主要来源于样品称量、样品消解液定容体积和测定样品消解液中各元素的浓度,对这些分量进行了量化计算。土壤中钡、铬和锰的质量分数可分别表示为218.5±17.1,342.5±40.4,1468.9±47.1mg/kg。影响各元素含量测量不确定度的主要因素是测量样品消解液中各元素的浓度引起的不确定度。     

5种抗肝癌中草药中锌、铜、锰、铁和镁的含量分析

采用火焰原子吸收光谱法测定了半边莲、半枝莲、山豆根、苦参和葛根5种抗肝癌中草药中Zn、Cu、Mn、Fe和Mg的含量。结果表明,各元素在所选的中草药中含量丰富。5种中草药中,半枝莲的Zn和Mn含量最高,半边莲的Cu和Fe含量最高,山豆根中Zn/Cu比值最高,而Mg的含量则均很高。该结果可为研究中草药的抗肝癌作用机理提供一定的信息。     

男性型秃发患者与健康人发中微量元素锌,铜,铁和锰含量的测定

本文采用火焰原子吸收法对３０例男性型秃发患者及３８例毛发健康男性对照者头发中微量元素锌、铜、铁和锰的含量进行了测定。本文为开展男性型秃发的病因学和治疗学研究提供了有益的资料。     

Aerodynamic, laryngoscopic, and perceptual-acoustic characteristics in dysphonic females with posterior glottal chinks: A retrospective study

The relationships of posterior glottal chink magnitude and nodule size with phonatory flow rate, resistance, and breathiness were investigated in 70 women in a retrospective study. Results demonstrated a strong relationship between chink size airflow, but no relationship between nodule size and airflow. Resistance and nodule size were moderately correlated. Breathiness was not explained by airflow, nodule size, or chink magnitude. Subjects in therapy demonstrated concurrent reductions in airflow and chink size. For the laryngeal magnitude measures, visual-perceptual ratings were compared with computer-based measurements. The discussion includes a critical analysis of measurement methods and directions for future research.     

Personality,Psychological Factors,and Behavioral Tendencies in Children With Vocal Nodules: A Systematic Review

ObjectivesThis systematic review examined the evidence linking vocal nodule development in children to personality traits, psychological factors, and associated behavioral tendencies.MethodsFour electronic databases—PubMed, Scopus, ScienceDirect, EBSCO Host—as well as the reference lists from articles (including online sources) were searched. After screening for relevance, eight comparative, case-control studies were identified that met inclusion criteria. The quality of each study was evaluated by two raters using a modified, standardized checklist.ResultsFour studies were rated as “good quality” and four were “fair”. The questionnaires used to measure personality or psychological factors varied widely among the studies, and the results linking personality dispositions (and associated behavioral inclinations) to vocal nodule development in children were mixed.ConclusionsFair to good quality evidence exists to suggest that psychological factors or personality traits related to extraversion and impulsivity (and their related behavioral inclinations) might predispose children to vocal nodules and deserve further attention. Clinical implications, limitations of the current systematic review, and recommendations for future research are also discussed.