冶金标准样品特性量值的不确定度评定

标准样品特性量值测不确定度的评定,必须依照一个暨定的测量程序和一个具体的实物。其 A 类不确定度为一个预先确定的测量模型一次抽样子样本统计估计的不确定度,B 类不确定度包括:计量器具及校准系统不确定度分量,不同测量方法不确定度分量,不同试验条件不确定度分量。定值程序的制定应尽可能将 B 类分量随机化,未随机化的部分 B 类分量估计出来后计入合成不确定度中。

环境监测中样品的两种编号方法

文章提供了两种样品的编号方法,即纯数字编号法和按样品属性编号法,很好地满足了环境监测对样品编号的要求,可供各级环境监测部门参考。

金属特性对激光诱导击穿光谱最佳实验参数的影响

采用波长为532 nm的单脉冲激光诱导两种金属样品铜和锌,产生等离子光谱,固定激光能量40 mJ、门宽100 ns、光谱仪入射狭缝0.1 mm、ICCD增益100等参数,研究金属样品物理化学特性对会聚透镜焦点到样品表面距离、ICCD采集延迟等最优化实验参数的影响.实验中分别选取铜样品Cu(I)521.82 nm和锌样品Zn(I)481.053 nm谱线作为LIBS信号,实验测定的透镜焦点在距样品表面不同距离处的LIBS信号强度,结果表明铜和锌样品的聚焦透镜焦点分别在样品表面内距表面的距离为5 mm和5.5 mm时得到光谱信号强度最大;铜和锌的ICCD探测延时分别为1300 ns和1100 ns时等离子体光谱信号的信噪比最大并具有可观测的强度,依据铜和锌样品物理化学特性的差异对实验结果进行了合理的分析与讨论,为后续研究金属样品LIBS技术的基底效应、纳米结构增强激光诱导击穿光谱机理提供数据参考.

温度的改变对激光诱导炉渣等离子体信号的影响

本文以激光诱导击穿光谱技术为基础,搭建激光诱导击穿光谱实验平台,以炉渣为研究背景,通过击穿炉渣中等离子体来获取炉渣光谱图,以炉渣中原子谱线CaⅠ:428. 28 nm、离子谱线CaⅡ:393. 37 nm和Si原子谱线SiⅠ:252. 91 nm为研究对象,探究温度的改变时对信号强度、信号稳定性和采集延时的影响,通过实验得出当温度在1 000℃时的光谱信号强度和稳定性明显好于200℃,温度改变对光谱信号强度的采集延时也会发生变化,在50℃时延时时间为2μs时信号强度最好,当温度大于400℃时延时时间为1μs时光谱强度最好。

Genetic Diversity Analysis of Three Guizhou Local Pig Breeds Using Microsatellite DNA Markers

[Objective] The research aimed to provide the genetic basis for the protection, development and utilization of Guizhou local pig breeds. [Method] From 27 pairs of porcine microsatellite primers recommended by Food and Agriculture Organization of the United Nations （FAO） and international Society for Animal Genetics （ISAG）, six pairs （S0155, SW240, IGF1, SW951, SW857, SW24） were selected for microsatellite DNA detection of three Guizhou local pig breeds, including Nuogu Pig, Kele Pig and Guanling Pig. Subsequently, their genetic diversities were analyzed. [ Result] The three pig breeds were high polymorphic at the six microsatellite loci （PIC 〉0.5）. The Nei＇s standard genetic distance of them was 0.206 3 -0.481 5. The genetic distance between Nuogu Pig and Kele Pig Was the closest, and that between Nuogu Pig and Guanling Pig was the furthest. [ Conclusion] The three Guizhou local pig breeds are in high genetic diversities. Nuogu Pig is a special type of Kele Pig, an excellent Chinese local pig breed.

Experimental investigation on the relevance of mechanical properties and porosity of sandstone after hydrochemical erosion

Under the effect of chemical etching,the macroscopic mechanical properties,mesoscopic structure,mineral content,and porosity of rocks undergo significant changes,which can lead to the geological disasters; thus,an understanding of changes in the microscopic and macroscopic structure of rocks after chemical etching is crucial.In this study,uniaxial mechanical tests and nuclear magnetic resonance(NMR) spectroscopy were carried out on sandstone samples that had been previously subjected to chemical erosion under different p H values.The aim was to study changes in properties and mechanical characteristics,including deformation and strength characteristics,of the rock,and microscopic pore variation characteristics,and to perform preliminary studies of the chemical corrosion mechanism.Results show that different chemical solutions have a significant influence on the uniaxial compressive strength,the axial strain corresponding to the peak axial stress,elastic modulus,etc.With the passage of time,porosity increases gradually with exposure to different chemical solutions,and exposure to chemical solutions results in large changes in the NMR T2 curve and T2 spectrum area.Sandstone exposed to different chemical solutions exhibits different corrosion mechanisms; the root cause is the change of mineral.

Laboratory Investigation of Disintegration Characteristics of Purple Mudstone under Different Hydrothermal Conditions

Disintegration of rock is one of the primary processes of soil formation and geomorphology and is affected considerably by water and heat.This study focused on the disintegration characteristics under laboratory conditions of typical purple mudstone from the Tuodian group of Jurassic red beds(J3t) in Tuodian Town,Shuangbai county,Yunnan Province of southern China.The fresh mudstone was subjected to alternating applications of water,heat and hydrothermal interaction during five treatments:wetting-drying(WD),saturation(ST),refrigeration-heating(RH),a combination of wetting-drying and refrigeration-heating(WDRH),and a combination of saturation and refrigeration-heating(STRH).Each treatment was run in twenty-four cycles.The results showed that there are three types of disintegration:collapsing disintegration,exfoliation disintegration and imperceptible disintegration.The cumulative disintegration rate(percentage of cumulative disintegrated mass to the initiative sample mass passed through a 2 mm sieve) produced a 'S'-shape function when related to treatment cycle time and closely fit a logistic model(R2 > 0.99).The rank order of the cumulative disintegration rate resulting from the five treatments was as the following:WDRH > STRH > ST > WD > RH.Because of alternating periods of moisture and dryness,WD caused the most disintegration,while RH alone resulted in imperceptible disintegration.Additionally,there was a negative correlation between the disintegration rate of each treatment cycle(percentage of disintegrated mass to the treated sample mass) and treatment cycle number.There was a positive correlation between this rate and temperature change under moist conditions,indicating that a change in temperature greatly accelerates the disintegration of parent rock when water was supplied.

Local Data Analysis for Eliminating End Restraint of Triaxial Specimen

A data processing method was proposed for eliminating the end restraint in triaxial tests of soil. A digital image processing method was used to calculate the local deformations and local stresses for any region on the surface of triaxial soil specimens. The principle and implementation of this digital image processing method were introduced as well as the calculation method for local mechanical properties of soil specimens. Comparisons were made between the test results calculated by the data from both the entire specimen and local regions, and it was found that the deformations were more uniform in the middle region compared with the entire specimen. In order to quantify the nonuniform characteristic of deformation, the non-uniformity coefficients of strain were defined and calculated. Traditional and end-lubricated triaxial tests were conducted under the same condition to investigate the effects of using local region data for deformation calculation on eliminating the end restraint of specimens. After the statistical analysis of all test results, it was concluded that for the tested soil specimen with the size of 39.1 mm × 80 ram, the utilization of the middle 35 mm region of traditional specimens in data processing had a better effect on eliminating end restraint compared with end lubrication. Furthermore, the local data analysis in this paper was validated through the comparisons with the test results from other researchers.

Characterization of Genetic and Phenotypic Diversities in the Potato （Solanum tuberosum L.） Population in Kosovo

The presence and introduction of new potato cultivars in Kosovo has increased the yield per unit area but reduced the cultivation of native potato population. Indigenous potato is linked to specific adaptations to local fanning system and specific agro ecological conditions. This research was conducted in Prishtina region which is located in the Kosovo agro ecological region （42°38′97″ latitude and 21°08′45＂ longitude at 574 m.a.s.l ）. Plant material used in this research was 18 potato accessions with different origins. The experimental design was a randomized complete block （RCB） with three replicates, while the plot sizes were 4.20 m^2. All observation and analysis were carried out on 12 plants from each accession. All characters were measured in the field and laboratory at the normal harvest time. Morphological diversity was characterized using standard descriptors. The genetic diversity studies of the investigated potato accessions showed significant genetic variation on 17 physiological and chemical parameters, which could be largely due to that they were of different origins. The genetic diversity of potato cultivars offers a wealth of natural resources from which breeders can select the most desirable genotypes based on their favorable traits.

Deformation characteristics and constitutive model of seafloor massive sulfides

Deformation characteristics and constitutive model of seafloor massive sulfide(SMS)were selected as the research object.Uniaxial/triaxial compression test were carried out on the mineral samples,and the deformation characteristics of specimens under various conditions were studied.According to characteristics of the mineral,a new three stages constitutive equation was proposed.The conclusions are as follows:The axial strain,peak strain and maximum strength of seafloor massive sulfide increase with the confining pressure.The elastic modulus of the metal sulfide samples is decreased sharply with the increase of confining pressure.According to characteristics of seafloor massive sulfide,the constitutive equation is divided into three parts,the comparison between theoretical curves and experimental data shows that both of them are in good agreement,which also proves the correctness of the constitutive equation for uniaxial compression.

激光诱导炉渣等离子体信号的稳定性研究

激光诱导等离子体受激光能量大小、激光频率、样品特性、采集延时等实验参数的影响,这些因素变动直接影响物质成分定量分析的准确性。本文搭建激光诱导击穿光谱实验平台,以炉渣为研究背景,以炉渣中原子谱线CaI:428.28 nm、离子谱线CaII:393.37 nm和Si原子谱线SiI:252.91 nm为研究对象,观察信号强度随采集延时、激光能量的波动和激光聚焦位置的变化规律。通过实验测得最佳延时时间为1us时信号强度最好,激光能量的波动对信号的影响并无明显影响,激光聚焦位置在样品表面以下2-3 mm处为最佳实验条件。

Soil microbial properties under different vegetation types on Mountain Han

This study investigated the influence of broadleaf and conifer vegetation on soil microbial communities in a distinct vertical distribution belt in Northeast China.Soil samples were taken at 0-5,5-10 and 10-20 cm depths from four vegetation types at different altitudes,which were characterized by poplar(Populus davidiana)(1250-1300 m),poplar(P.davidiana) mixed with birch(Betula platyphylla)(1370-1550 m),birch(B.platyphylla)(1550-1720 m),and larch(Larix principis-rupprechtii)(1840-1890 m).Microbial biomass and community structure were determined using the fumigation-extraction method and phospholipid fatty acid(PLFA) analysis,and soil fungal community level physiological profiles(CLPP) were characterized using Biolog FF Microplates.It was found that soil properties,especially soil organic carbon and water content,contributed significantly to the variations in soil microbes.With increasing soil depth,the soil microbial biomass,fungal biomass,and fungal catabolic ability diminished;however,the ratio of fungi to bacteria increased.The fungal ratio was higher under larch forests compared to that under poplar,birch,and their mixed forests,although the soil microbial biomass was lower.The direct contribution of vegetation types to the soil microbial community variation was 12%.If the indirect contribution through soil organic carbon was included,variations in the vegetation type had substantial influences on soil microbial composition and diversity.

The measurement and model construction of complex permittivity of vegetation

The complex permittivity of targeted objects is an important factor that influences its microwave radiation and scattering characteristics.In the quantitative research of microwave remote sensing,the study of the dielectric properties of the vegetation to establish the relationship between its specific physical parameters and complex permittivity is fundamental.In this study,six categories of vegetation samples were collected at the city of Zhangye,a key research area of the Heihe watershed allied telemetry experimental research.The vector network analyzer E8362B was used to measure the complex permittivity of these samples from 0.2 to 20 GHz by the coaxial probe technique.The research focused mainly on the corn leaves,and an empirical model was established between the gravimetric moisture and the real/imaginary parts of complex permittivity at the main frequency points of microwave sensors.Furthermore,the empirical model and the classical Debye-Cole model were compared and verified by the measured data collected from the Huailai County of Hebei Province.The results show that the newly- established empirical model is more accurate and more practical as compared to the traditional Debye-Cole model.