药用聚丙烯密度测量的不确定度评定

目的:评估药用聚丙烯瓶密度测定的不确定度,以控制药品包装材料的质量。方法:通过建立数学模型,分析称量、温度、容积密度等因素对密度测量不确定度的贡献,计算各不确定度分量,对药用聚丙烯瓶密度的不确定度进行评估。结果:给出合成不确定度和扩展不确定度,不确定度主要来源于样品质量的称量。结论:建立的方法可用于药用聚丙烯瓶密度测定的不确定度评价。     

塑料密度测量的不确定度评定

采用D-H100型密度测定仪对聚乙烯塑料的密度测量进行了不确定度评定,分析了密度测量过程中不确定度的主要来源,并对各不确定度分量进行量化,求得合成标准不确定度和扩展不确定度分别为0.0005g/cm3和0.0010g/cm3.     

凯氏定氮法测定大豆粉中蛋白质的不确定度评定

通过对凯氏定氮法测大豆粉中蛋白质含量的测定过程的研究,确定测定结果的不确定度。建立不确定度的数学模型,对各不确定度分量进行合成和扩展,最终建立大豆粉中蛋白质的不确定度评定方法。影响测量结果不确定度的因素共有5项,按其影响大小顺序排列分别为测量重复性、试样质量、样液滴定体积、样液移取体积以及盐酸标准溶液浓度。其不确定度报告为大豆粉中蛋白质含量为:(39.0±0.6)g/100g,包含因子k=2。     

涂料密度测定的不确定度评定

根据JJF 1059--1999,以铝粉沥青船底漆密度的测定为例,对涂料密度测定的不确定度进行了评定。结果表明:该涂料的密度ρ_23℃=1.227 6 g·mL^-1,相对扩展不确定度U_rel=0.05%,扩展不确定度U=0.000 7 g·mL^-1,包含因子k=2;该结果比GB/T 6750-2007《色漆和清漆密度的测定比重瓶法》给出的不确定度低一个数量级。     

原子吸收光谱法测定工作场所空气中镍的不确定度评定

依据JJF1059.1-2012,分析了应用原子吸收法测定工作场所空气镍及其化合物过程中的影响不确定度因素,从采集气样体积和采气后滤膜消化液待测物浓度和定容体积三个部分,确定并量化各不确定度分量。本次测量相对合成标准不确定度为0.0428,其中最大不确定度分量是样品浓度测量过程中的A类合成不确定度,包括样品测量和标准曲线测量过程中随机因素引入,B类合成不确定度相对较小。消化样定容体积测量以及温度计和气压表等对采集气样体积引入的不确定度可忽略。     

熔融制样-波长色散X射线荧光光谱法测定铁矿石中二氧化硅含量测量不确定度评定

本研究采用熔片制样-波长色散X射线荧光光谱法测定铁矿石中二氧化硅含量,并对其不确定度进行了评定。建立了不确定度评估的数学模型,对不确定度来源进行了分析,分别计算出不确定度分量并合成不确定度,最终确定了分析结果的置信区间。评估结果表明,校准样品及工作曲线的不确定度对测量不确定度的影响最大。     

6号燃料油密度的测定(密度计法)不确定度评定

文章介绍了燃料油密度测定对指导生产的意义,同时对测定6号燃料油密度所依据的标准以及测量原理和测量方法进行了阐述,重点对测定结果的测量不确定度进行了详细评定。     

建筑用聚氯乙烯(PVC)排水管密度测量不确定度的评定

介绍建筑用PVC排水管的特点及其应用,根据密度测量标准建立PVC排水管密度的测量不确定度的数学模型,并结合实例对不确定度来源进行分析,通过对不确定度分量的计算及合成得出当PVC排水管密度为1.4896g/cm~3时,其扩展不确定度为0.0007g/cm~3(k=2)。结果表明试样在去离子水中的称量重复性和去离子水的密度是影响密度不确定度的主要因素。     

微晶蜡含油量不确定性评估

分析了微晶蜡含油量测定过程中影响检测结果的不确定度因素并进行了评估。通过计算重复性、残油质量、样品质量、溶剂体积、蒸发溶剂体积等因素带来的不确定度,得到了微晶蜡含油量测定结果的合成不确定度。实验结果表明,微晶蜡含油量测定不确定度主要影响因素为重复性,其次是溶剂体积和残油质量带来的不确定度。通过对不确定度进行评估,有利于提高检测结果可靠性,可以为准确测定微晶蜡含油量提供理论依据。     

亚甲基蓝分光光度法测定环境空气硫化氢的不确定度评定

分析了应用亚甲基蓝分光光度法测定环境空气硫化氢测试过程中不确定度影响因素,本法测量不确定度主要来源为标准溶液、标准曲线拟合、分光光度计、样品重复测定、吸收液体积和采集大气样气体标干体积这六部分引入的不确定度。其中大气采样体积引入相对不确定度为0.012,其他部分合成相对不确定度为0.033。结果为(0.014±0.001)mg/m3,k=2。(约95%置信水平)     

硅砖显气孔率测量结果的不确定度分析与评定

摘要：按照GB／T2997-2000测量并计算了同一批次硅砖试样的显气孔率,对影响显气孔率的测量不确定度分量进行了分析和评定,并对测量不确定度的各个分量进行了计算和合成,给出了该硅砖显气孔率的不确定度报告为：显气孔率7ra=20．2％0,测量结果的扩展不确定度U=0．2％,包含因子k=2。     

Thermal Transmittance of Porous Hollow Clay Brick by Guarded Hot Box Method

The thermal property of a porous hollow clay brick was determined by measuring the thermal transmittance of the wall made of porous hollow clay bricks. Prior to the production of porous hollow clay bricks, nonporous and porous tiny clay bricks were prepared to determine the physico-mechanical properties by modifying the amount of wood flour and firing temperature. The bricks were produced by uniaxial pressing and then fired in an electric furnace. Their physico-mechanical properties were measured by water absorption, apparent porosity, bulk density, and compressive strength. The porous tiny clay bricks were produced with three types of wood flour: coarse wood flour (1–0.36 mm), medium-sized wood flour (0.36–0.15 mm), and fine wood flour (< 0.08 mm). The thermal transmittance of porous hollow clay bricks was determined through the guarded hot box method, which measures the wall made of porous hollow clay bricks and nonporous cement bricks. The two walls had a thermal transmittance of 1.42 and 2.72 \(\hbox {W}\cdot \hbox {m}^{-2}\cdot \hbox {K}^{-1}\), respectively. The difference in thermal transmittance was due to the pores created with fine wood flour (< 0.08 mm) as a pore-forming agent.     

Fly ash-lime-phosphogypsum cementitious binder: A new trend in bricks

Fly ash-lime-phosphogypsum (FaL-G) bricks are one of the best alternatives to the conventional burnt clay bricks. This paper gives the results of an experimental investigation in which the compressive strength, water absorption, density and durability of Fly ash-lime-phosphogypsum (FaL-G) bricks were investigated by using varying quantities of fly ash, lime and calcined phosphogypsum. The properties of Fly ash-lime-phosphogypsum (FaL-G) bricks are compared with those of the ordinary burnt clay bricks. The results indicate that these bricks are lighter in weight, durable in aggressive environments and have sufficient strength for their use in building construction.     

Feasibility study of using brick made from municipal solid waste incinerator fly ash slag

This study deals with the effect of MSWI slag on fired clay bricks. Brick samples were heated to temperatures which varied from 800 to 1,000 degrees C for 6h, with a heating rate of 10 degrees C/min. The material properties of the resultant material then determined, including speciation variation, loss on ignition, shrinkage, bulk density, 24-h absorption rate and compressive strength. Toxicity Characteristic Leaching Procedure tests were also conducted. The results indicate that the heavy metal concentrations in the leachates met the current regulatory thresholds. Increasing the amount of MSWI slag resulted in a decrease in the water absorption rate and an increase in the compressive strength of the MSWI-slag bricks. The 24-h absorption rate and compressive strength of the MSWI-slag brick made from samples containing slag sintered at 1,000 degrees C all met the Chinese National Standard (CNS) building requirements for second-class brick. The addition of MSWI slag to the mixture reduced the degree of firing shrinkage. This indicates that MSWI slag is indeed suitable for the partial replacement of clay in bricks.     

Design thermal values for unfired clay bricks

This paper reports on a laboratory and theoretical method for determining the design values for thermal conductivity and thermal resistance of unfired clay masonry bricks from both experimental and theoretical design point of view. The paper describes the methodology of obtaining these values using the measured lower and upper lambda limits. In order to determine the basic design thermal value and the design thermal resistance, a Laser-comp FOX 200 thermal conductivity meter equipped with WinTherm32an software package was employed for the laboratory data collection and analysis. Lime or Portland cement (PC)-activated Ground Granulated Blastfurnace Slag (GGBS) binder was used to stabilise Lower Oxford Clay (LOC) for unfired masonry brick specimen production. The major influence of the design values on the thermal conductivity and thermal resistance are illustrated in this study, using two different types of unfired clay bricks (LG and PG) at 2% moisture content prior to test. This paper covers conductivity test for each unfired clay bricks within the temperature range 2.5–17.5 °C. The measured thermal properties of the unfired clay bricks were compared to the design thermal properties of fired bricks. The results were used to predict the design thermal values of unfired clay masonry bricks at varied density and moisture contents prior to testing. A comparison of the measured thermal values for the unfired bricks to the design thermal values of fired clay bricks can also be seen. The results demonstrate that the unfired clay bricks were able to comply with the design thermal requirements for clay masonry units, suggesting that the unfired clay bricks can be used for low-medium cost housing and energy efficient masonry structures.     

On Earth Stabilization with Natural Polymers for Earth Masonry Construction

In this paper we study the problem of preparing adobe bricks for earth construction as little erodable as possible. We have therefore tested earthen specimens stabilised with both vegetal fibres and a compound of natural polymers, and we have compared their behaviour to that one of specimens stabilised only with fibres. We have studied how the stabilization with these natural polymers modifies porosity and bulk density, and how it improves both the behaviour under the water action and the compression strength. This kind of stabilization appears to give the earth a very good behaviour under the water action; moreover we have found out that the compression strength has been significantly increased, too.     

Study on the characteristics of building bricks produced from reservoir sediment

This research investigates the feasibility of building bricks produced from reservoir sediment sintering using various sintering temperatures and clay additions. The experimental results indicate that sintered specimen densification occurred at sintering temperatures of 1050-1100 degrees C. Increasing the sintering temperature decreases the water absorption and increases the shrinkage, density and compressive strength of sintered specimens. The experiments were conducted at a temperature ranged from 1050 to 1150 degrees C with clay addition contents varying from 0% to 20%. All sintered specimens made from reservoir sediment were in compliance with Taiwan building bricks criteria. This means that raw materials for producing building bricks can be replaced with reservoir sediment. The metals concentrations of the leachate from the toxicity characteristics leaching procedure (TCLP) test are all complying with the current regulatory limits. These results confirm the feasibility of using reservoir sediment to produce sintered construction brick.     

硅砖线膨胀率和平均线膨胀系数测定的不确定度评定

按照GB／T7320．1—2000的方法测试并计算了一批硅砖试样的线膨胀率和平均线膨胀系数,对影响其线膨胀率和平均线膨胀系数的不确定度分量进行了分析,并对不确定度的各个分量进行了计算和合成,给出了该硅砖的不确定度：ρ=1．06％,U=0．01％,k=2; α=10．8×10^-6℃-1,U=0．1×10^-6℃-1,k=2。     

Some mechanical and thermal properties of clay bricks for the Jordan valley region

An experimental investigation was carried out to study the use of different locally available additives to Al-Karamah clay to produce bricks to suit the weather conditions in the Jordan Valley region. The parameters investigated were the percentages of additives by volume, compaction rate, and drying rate. The ultimate compressive strength and thermal properties of the bricks were measured. The study indicated that Al-Karamah clay can be used successfully to manufacture solid clay bricks which suit the Jordan Valley region.     

Versuche am Bau mit Injektionsankern im Mauerwerk nach Technischer Regel des DIBt

Tests on construction site for metal injection anchors for use in masonry according to the DIBt Technical Rule – Part 1: Overview On construction sites, one encounters a large number of bricks that differ in material (clay, autoclaved aerated concrete, calcium silicate, lightweight concrete or normal concrete), structure (solid bricks, perforated bricks with or without insulation filling), geometry, bulk density and compressive strength. In the context of approval procedures for plastic anchors and metal injection anchors, however, it will only ever be possible for anchor manufacturers to map part of this variety of masonry stones as a permissible base material. Tests on construction site allow the user, under certain conditions, to design and install in accordance with the approval if the base material actual available on construction site is not shown in the approval for the anchor system. This article is an excerpt from issue 4 of the series of publications of the ?Deutscher Ausschuss für Mauerwerk e.V. (DAfM)” (Dübel‐)Versuche am Bauwerk in Mauerwerk – Aktuelle Regelungen für Kunststoffdübel und Metall‐Injektionsanker zur Verankerung im Mauerwerk” and provides an overview to the existing set of rules to be observed – in particular to one of the two current Technical Rules of the Deutsches Institut für Bautechnik (DIBt) ?Durchführung und Auswertung von Versuchen am Bau für Injektionsankersysteme im Mauerwerk”.