石灰岩中游离二氧化硅化学物相分析方法的标准化研究

介绍了石灰岩中游离二氧化硅的化学物相分析方法。选择磷酸溶矿 ,再以氟硼酸解聚已溶出的硅酸 ,使游离二氧化硅与其他矿物分离 ,再用重量法进行测定 ,并按GB 6379- 86测试方法的精密度 ,通过实验室间试验确定标准测试方法的重复性和再现性。通过取样、制样、样品均匀性检查、精密度试验等步骤 。

锑矿石化学物相分析方法精密度的确定与评估

长期以来化学物相分析方法的精密度一直没有得到科学的量化控制,实验室间的精密度更是缺少控制限要求。实验在建立我国具有代表性锑矿石化学物相分析方法的过程中,按照标准GB/T6379.2—2004《测量方法与结果的准确度(正确度与精密度)第2部分:确定标准测量方法重复性与再现性的基本方法》,通过配制6个水平的协作试验样品,选择Al_2O_3、TFe(以Fe_2O_3形式表示)、CaO、MgO、Sb、S等主量组分或元素进行均匀性检验,检验结果 F值均小于临界值4.39,表明试验样品是均匀的。组织8家实验室进行协作试验,获得锑总量和3个锑矿物相中的锑随质量分数(m)变化的重复性限(r)和再限性限(R),结果表明,在确定的矿石中总锑和各矿物相中锑的重复性限和再现性限中,总锑的重复性限和再现性限最小,均小于锑矿石各相态分析的重复性限和再现性限,化学物相分析方法重复性限和再现性限参数验证了化学物相分析误差主要来源于串相误差的基本特性。锑矿石化学物相的精密度为锑矿石化学物相分析标准方法的建立和质量控制提供了依据。

测井相序分析方法

测井相分析方法已受到人们的普遍重视,并已建立了多种实用的程序系统。但是,测井相分析所依据的只是测井曲线的幅度信息,得到的实际上仅为待判井段的岩性类型。在沉积学中,相反映的是沉积时的物理、化学以及生物条件,而相序表达的则是沉积时间和空间的变化,并且两者有一定的相依性。

铁矿石的物相分析与方法应用改进

本文对铁矿石的物相分析方法应用进行了研究,阐述了铁矿石的测定方法,介绍了铁矿石的矿物分离技术,对铁矿石物相分离方法进行了改进研究,最后总结了铁矿石的物相分析方法的重要和要点,旨在提高铁矿石的物相分析水平。

金化学物相分析现状及浅析

化学物相分析是基于化合物化学元素性质的不同,利用化学分析的手段,研究物相组成和含量的方法。它是研究地质学的重要手段,对研究矿物或矿床成因,寻找有用矿物、考查矿物的赋存状态,对矿床进行工业评价、矿物资源综合利用和选冶工艺流程的研究等方面有着重要的科学意义和经济价值。本文就目前的金化学物相分析现状进行讨论。

沉积相的一些术语定义的新思考:基于迈尔(Miall,1985)的文章

近年来,《古地理学报》(中文版及英文版)连续收到一些来稿,其作者根据迈尔(Miall,1985)文章的观点和方法,把他们研究地区碎屑岩剖面中的每个岩层中的岩石挑出来,归纳出一些岩石类型,如砾岩、砂岩、细粒岩等,并称它们为岩相(lithofacies)。这不符合沉积相的定义。我曾写过几篇文章,即冯增昭(2018,2020)及Feng(2019),指出这些问题,希望国内外的作者、尤其是国内的作者,不再继续盲目地引用和传播迈尔(1985)文章的观点和方法。迈尔是第1个称岩石(实际上是沉积物)为岩相的人,他的观点和他提出的相分析方法误导了沉积相的正确定义及正常的相分析方法。本文主要讨论迈尔(Miall,1985)文章中的问题,即他把沉积物当作岩相并用岩相分析相。不讨论他文章的贡献及建筑单元中的一些术语欠严谨的问题。在这里,必须申明,本文中的相,是沉积岩石学中的相,不是火成岩岩石学、变质岩岩石学、古生物学、地层学、地球物理学、地球化学等地质学分支学科中的相。岩相、相和沉积相是同义的术语。当然,这些术语的定义是有争议的,希望遵循“百花齐放和百家争鸣”的方针和地质实践,逐步地解决这些争议。

电涡流相位梯度及其在导电材料缺陷识别中的应用

使用空间域相频谱分析方法,将相位梯度作为缺陷检测信号特征量,对不同类型的缺陷进行检测和分类。数字相敏解调技术用于提取检测信号的相位梯度。采用双空气芯线圈涡流传感器并施加1-10 kHz多频激励信号,对平板金属样件进行表面缺陷、下表面缺陷、内部缺陷的识别及分类。实验结果证明,实验系统可以有效地检测出缺陷,并通过空间域相频谱分析得到可视化检测结果,采用相位梯度作为特征量有效抑制了提离噪声对检测结果的影响。

基于ISM-MICMAC的企业危化品道路运输事故致因研究

准确辨识企业危化品道路运输事故致因,构建企业危化品道路运输事故致因指标体系,理清企业危化品道路运输事故致因分类、层次结构和影响关系,对于企业危化品道路运输事故预防意义重大。基于4M事故致因理论,提取可能引起企业危化品道路运输事故的22个事故致因,构建企业危化品事故致因指标体系,在此基础上运用ISM模型进行多级递阶层次结构划分,并结合MICMAC方法确定事故致因属性特征。研究结果表明,企业危化品道路运输事故的22个事故致因可用ISM模型划分为7级3阶的“多级阶梯结构”,包括浅表层致因5个、中间层致因3个、深层次致因14个,其中控制深层次致因可以从根源上有效避免事故发生;通过MICMAC方法将22个事故致因划分为自治因素、独立因素、关联因素和依赖因素4类,其中涉及独立因素的7个事故致因是引起企业危化品道路运输事故发生的最根本、最关键致因。研究结果可为企业危化品道路运输事故预防管理提供借鉴思路。

基于复合信息空间的语音识别训练系统研究

首先介绍了复杂系统、复合信息空间等相关知识,在此基础上提出一种在复合信息空间中基于知识的、定性与定量相结合的分析方法,并结合一个语音识别训练系统的实例对这种方法的应用进行详细介绍。

Phase aberration correction in ultrasonic phased array non-destructive testing systems

Phase aberration correction for medical ultrasound systems has attracted a great deal of attention. Since phased array techniques are now widely employed for industrial non-destructive testing （NDT） applications in various fields, the problem of phase aberrations in the process of NDT testing is considered. The technique of cross-covariance for phase aberration correction is presented. The performance of the technique for phase aberration correction is tested by means of echo signals obtained in practical non-destructive testing experiment. The results show that the technique has the better accuracy of phase correction.

Temporal-spatial cross-correlation analysis of non-stationary near-surface wind speed time series

Temporal-spatial cross-correlation analysis of non-stationary wind speed time series plays a crucial role in wind field reconstruction as well as in wind pattern recognition.Firstly,the near-surface wind speed time series recorded at different locations are studied using the detrended fluctuation analysis(DFA),and the corresponding scaling exponents are larger than 1.This indicates that all these wind speed time series have non-stationary characteristics.Secondly,concerning this special feature( i.e.,non-stationarity)of wind signals,a cross-correlation analysis method,namely detrended cross-correlation analysis(DCCA) coefficient,is employed to evaluate the temporal-spatial cross-correlations between non-stationary time series of different anemometer pairs.Finally,experiments on ten wind speed data synchronously collected by the ten anemometers with equidistant arrangement illustrate that the method of DCCA cross-correlation coefficient can accurately analyze full-scale temporal-spatial cross-correlation between non-stationary time series and also can easily identify the seasonal component,while three traditional cross-correlation techniques(i.e.,Pearson coefficient,cross-correlation function,and DCCA method) cannot give us these information directly.

Recovery of Dyestuffs from Dilute Solution with Two-phase Electrophoresis

Two-phase electrophoresis was used to separate the dyestuffs from their dilute solutions. Several dyestuffs (naphthol green B, acid-chrome blue K, methyl blue and direct fast torquoise blue GL, and n-butanol) were treated in a self-designed experimental setup and the mass transfer characteristics in this process were studied. The results confirm the potential of this technique for recovering dyestuffs from their dilute solutions.

Predicting Arabidopsis thaliana Gene Function by Transitiving Co-expression in Shortest-path

The present paper predicted the function of unknow genes by analyzing the co-expression data of Arabidopsis thaliana from biological pathway based on the shortest-path algorithm. This paper proposed that transitive co-expression among genes can be used as an important attribute to link genes of the same biological pathway. The genes from the same biological pathway with similar functions are strongly correlated in expression. Moreover,the function of unknown genes can be predicted by the known genes where they are strongly correlated in expression lying on the same shortest-path from the biological pathway. Analyzing the Arabidopsis thaliana from the biological pathway,this study showed that this method can reliably reveal function of the unknown Arabidopsis thaliana genes and the approach of predicting gene function by transitiving co-expression in shortest-path is feasible and effective.

Gas monitoring data anomaly identification based on spatio-temporal correlativity analysis

Based on spatio-temporal correlativity analysis method, the automatic identification techniques for data anomaly monitoring of coal mining working face gas are presented. The asynchronous correlative characteristics of gas migration in working face airflow direction are qualitatively analyzed. The calculation method of asynchronous correlation delay step and the prediction and inversion formulas of gas concentration changing with time and space after gas emission in the air return roadway are provided. By calculating one hundred and fifty groups of gas sensors data series from a coal mine which have the theoretical correlativity, the correlative coefficient values range of eight kinds of data anomaly is obtained. Then the gas moni- toring data anomaly identification algorithm based on spatio-temporal correlativity analysis is accordingly presented. In order to improve the efficiency of analysis, the gas sensors code rules which can express the spatial topological relations are sug- gested. The experiments indicate that methods presented in this article can effectively compensate the defects of methods based on a single gas sensor monitoring data.

Nonlinear finite-element-based structural system failure probability analysis methodology for gravity dams considering correlated failure modes

The structural system failure probability(SFP) is a valuable tool for evaluating the global safety level of concrete gravity dams.Traditional methods for estimating the failure probabilities are based on defined mathematical descriptions,namely,limit state functions of failure modes.Several problems are to be solved in the use of traditional methods for gravity dams.One is how to define the limit state function really reflecting the mechanical mechanism of the failure mode;another is how to understand the relationship among failure modes and enable the probability of the whole structure to be determined.Performing SFP analysis for a gravity dam system is a challenging task.This work proposes a novel nonlinear finite-element-based SFP analysis method for gravity dams.Firstly,reasonable nonlinear constitutive modes for dam concrete,concrete/rock interface and rock foundation are respectively introduced according to corresponding mechanical mechanisms.Meanwhile the response surface(RS) method is used to model limit state functions of main failure modes through the Monte Carlo(MC) simulation results of the dam-interface-foundation interaction finite element(FE) analysis.Secondly,a numerical SFP method is studied to compute the probabilities of several failure modes efficiently by simple matrix integration operations.Then,the nonlinear FE-based SFP analysis methodology for gravity dams considering correlated failure modes with the additional sensitivity analysis is proposed.Finally,a comprehensive computational platform for interfacing the proposed method with the open source FE code Code Aster is developed via a freely available MATLAB software tool(FERUM).This methodology is demonstrated by a case study of an existing gravity dam analysis,in which the dominant failure modes are identified,and the corresponding performance functions are established.Then,the dam failure probability of the structural system is obtained by the proposed method considering the correlation relationship of main failure modes on the basis of the mechanical mechanism analysis with the MC-FE simulations.

Evaluation of estimation methods for meiofaunal biomass from a meiofaunal survey in Bohai Bay

Studies in the coastal area of Bohai Bay,China,from July 2006 to October 2007,suggest that the method of meiofaunal biomass estimation affected the meiofaunal analysis.Conventional estimation methods that use a unique mean individual weight value for nematodes to calculate total biomass may cause deviation of the results.A modified estimation method,named the Subsection Count Method (SCM),was also used to calculate meiofaunal biomass.This entails only a slight increase in workload but generates results of greater accuracy.Results gained using each of these two methods were compared in the present study.The results show that the conventional method generally estimates a meiofaunal biomass.The difference between the two estimation methods was highly significant (P<0.01) for the spring and winter cruises.Furthermore,the estimation method for meiofaunal biomass affected the analysis of horizontal distribution and correlation with environmental factors.These findings highlight the importance of estimation methods for meiofaunal biomass and will hopefully stimulate further investigation and discussion of the topic.

Multi-attributed decision making for mining methods based on grey system and interval numbers

In the case of unknown weights, theories of multi-attributed decision making based on interval numbers and grey related analysis were used to optimize mining methods. As the representative of independence for the indicator, the smaller the correlation of indicators is, the greater the weight is. Hence, the weights of interval numbers of indicators were determined by using correlation coefficient. Relative closeness based on positive and negative ideal methods was calculated by introducing distance between interval numbers, which made decision making more rational and comprehensive. A new method of ranking interval numbers based on normal distribution was proposed for the optimization of mining methods, whose basic properties were discussed. Finally, the feasibility and effectiveness of this method were verified by theories and practice.

一类次线性Hill型方程的无穷小周期解

研究一类在原点附近满足次线性条件的二阶Hill型方程的周期解问题.利用相平面分析,在原点附近构造一系列充分小的圆环,使得Poincaré映射在这些圆环上具有扭转性.从而,通过应用推广的Poincaré-Birkhoff扭转定理证明无穷多个小振幅次调和解的存在性.进一步,再应用Massera定理得到至少一个调和解的存在性.

Phase Transitions in a Mixture of Hard-Sphere Dipoles and Neutral Hard Spheres

Using the reference hypernetted chain （RHNC） integral equation theory and a rigorous stability analysis method, we investigate the phase behavior of a mixture of hard-sphere dipoles and neutral hard spheres based on the correlations of the homogeneous isotropic phase. Lowering the temperature down to the points where the RHNC equations fail to have a solution, several ttuctuations strongly increase. At low densities our results indicate the onset of ／ chain formation, which is similar with the pure DHS system. At high densities, the results indicate the appearance of isotropic-to-ferroelectric transitions （small neutral hard spheres concentrations） and demixing transitions （large neutral hard spheres concentrations）.

Information Technology in Environmental Monitoring for Territorial System Ecological Assessment

The environmental monitoring dataset of Rivne region territory （Ukraine） was analyzed using remote sensing technology and statistical analysis. The article reveals approaches to anthropogenic impact specificity assessment based on methods of correlation analysis. The information technology to assess soil quality based on satellite images decoding was created.