在线红外水分仪和微波水分仪测量精度比较

为比较在线红外水分仪和微波水分仪的测量精度,分别使用在线红外水分仪和微波水分仪对烟叶和烟丝的含水率进行测量,取测量平均值,再用标准烘箱法对同一样品进行含水率检测。将烘箱法检测结果与两种水分仪的检测结果进行比较,得出结论：在线红外水分仪的检测精度优于在线微波水分仪,在线红外水分仪更适用于测量烟叶和烟丝含水率。     

烟草含水率不同检测方法对比研究

烟草物料含水率的检测方法现通用的是2小时100℃的烘箱法，但是随着检测结果的滞后，失去了对过程控制的指导作用，为了提高检测效率，更好地服务于生产，目前也有使用40分钟120℃和20分钟125℃的快速烘箱检测方式，但没有确切的论文或标准进行指导。为了验证检测结果的真实性，通过对烟草加工在线物料含水率不同时间、不同温度条件下的检测，说明含水率在不同的检测条件下，其检测结果是不一致的，存在显著差异。通过对比试验，用2小时100℃的烘箱法检测含水率，检测结果是可靠、真实的。     

两种测定三叶草中水分含量的方法比较

采用烘箱法和红外法两种不同的方法测定三叶草中水分含量,通过设置不同温度、不同时间和不同称样量测定三叶草水分含量,比较两种方法的精密度。结果表明：烘箱法测定三叶草含水率的最佳条件是称样量1g、温度110℃、时间6h,含水率为86.23±0.12%;红外法测定的最佳条件是称样量为1g、温度110℃、时间9min,含水率为81.34±0.62%。烘箱法的精密度高于红外法,应用中需准确测定水分含量时可优先考虑烘箱法。     

快速烘箱水分测定法

本文依据干燥原理,采用数学建模形式,寻找温度与水分的相关方程,求解烟丝水分快速烘箱法的最佳设定温度,然后对烟丝快速烘箱法所测量的水分值与标准烘箱法测量值相对比,修正快速烘箱法的测量值。     

纸张快速水分测定法和烘箱水分测定法的比较

比较了快速水分测定法和烘箱水分测定法的差异。结果表明,快速水分测定法在同一温度条件下,随着烘烤时间的延长,所测纸样品的水分含量值也随着增大,综合温度试验和时间实验,快速水分测定法以测定温度为115℃、测定时间为2.5min的测量值与烘箱水分测定法的测定值接近。     

剪切条件下油水乳状液含水率测量装置的设计

针对传统油水乳状液含水率测量装置的准确性低、成本高、无法实现动态测量的问题,设计一种剪切条件下乳状液含水率的测量装置。系统利用油水两相的介电及电导特性的差异性,采用交流阻抗法测量待测乳状液的复阻抗参数,从而获得乳状液的含水率特征。结合搅拌装置模拟油水乳状液在运输环境下的剪切环境,间接实现油水乳状液的动态测量。实验测试表明:装置具有良好的重复性和稳定性,可实现剪切条件下对乳状液复阻抗参数的测量,证明乳状液的阻抗参数与含水率存在明显的线性关系,对进一步研究管道中油水两相的流动性质具有一定的参考价值。     

粉粒农业物料水分测量方法探讨

综述国内外物料水分测量的研究,系统地比较研究了物料水分的测量方法及其原理,分析并介绍了粉粒农业物料的水分特性和测量方法,对常用的粉粒农业物料水分测量方法(中子测定法、红外线测定法、电导测定法和电容测定法)进行了评述.通过比较,提出了基于电容湿度传感器的粉粒农业物料的自动化水分测量系统的研发要求及虚用前景.     

一种测量吸湿性松散物料体积的热力学方法

本针对吸湿性松散物料体积测量的困难,引入了一种利用热力学原理来测量物料体积的方法,搭建了实验装置。对此热力过程进行了分析,并对此法测量的误差进行了讨论。     

生产井储层流量在线监测装置研究

研制了一套生产井储层流量在线监测装置。该装置利用超声多普勒频差测量油、气、水的总流量,采用对环境无安全隐患的双能级X射线测量油、气、水的分相含率,采用电导式传感器实现高含水率情况下含水率的快速测量。在室内三相流实验系统上进行了实验,油、水流量的测量误差均小于±7%,气流量的测量误差小于±14%。     

高精度石油水分在线测量技术的研究

提出了一种新的高精度石油水分在线测量技术———基于实时温度补偿的电容式水分测量技术,并提出了电容测量电路参数的最小二乘估计方法。介绍了电容传感器的工作原理、结构及函数模型,给出了电容测量原理及方法,推导了温度补偿的二元线性拟合算法。实验结果表明:在0~10%的含水率范围内,本方法的测量误差≤±0.1%,测量周期为1 s,能够实现低含水率情况下石油水分的高精度在线测量。     

Complex permittivity and moisture measurements of oil palm fruits using an open-ended coaxial sensor

An open-ended coaxial sensor for the determination of complex permittivity and moisture content of oil palm fruits is presented in this paper. The measurement system consisting of the sensor and a PC-controlled vector network analyzer have been tested successfully on a range of oil palm fruits of various degrees of ripeness. The initial values of the complex permittivity were estimated using the admittance model of the sensor. The amount of moisture content was found by matching the values of permittivity from the quasistatic model with the permittivity of a dielectric mixture model using the moisture content values obtained from the standard oven drying method.     

土壤界限含水率自动检测系统设计研究

为了解决传统土壤界限含水率检测中存在的需人工现场操作、耗时久、数据采集困难、数据传输实时性差等问题,设计了一种土壤界限含水率自动检测系统。该系统以西门子S7-200PLC为控制核心,由传送带、正方体容器、搅拌容器、电子秤、抹平系统、圆锥仪和加热箱等组成,使用MCGS组态软件进行数据监控,并采用采样烘干法测定含水率,液-塑限联合测定法测定液、塑性指数。实际应用中,该系统能够完成自动搅拌、多组数据同时测定和数据实时传送,基于含水率和液、塑性指数实现土体的分类以及地基土承载力的估算。该系统具有自动化程度高、操作简单及成本低廉的特点,能够广泛应用于各种土壤界限含水率的测定,对农业工程的设计和实施具有一定的参考价值。     

Granulation Moisture Content Analysis: An Evaluation of Two Instruments

Abstract

Reliable methods of determining moisture content of granulations are essential to develop products that are readily and consistently manufactured. This study evaluated two instruments for loss on drying (LOD) measurement, the Computrac model MA-5 and the Mark-I, Both instruments were evaluated using the USP oven method for LOD determination as a standard. All of these instruments/methods involved thermgravimetric analysis (TGA). Computrac MA-5 utilizes a heating coil as heat source and Mark-I uses four parallel quartz infrared heaters as heat source. Results showed that the Mark-I moisture analyzer and the oven method gave values much closer to those predicted for the compounds tested, while the Computrac seems to be inconsistent in determining the LOD of materials which are in equilibrium with their bound water of hydration and their evolved volatile compounds.     

烘干法模拟显示水分测定仪测得值的不确定度评定

烘干法水分测定仪是基于烘干原理直接对衡量样品表面分离物或微量水分进行计量分析的仪器。本文依据JJG658-2010《烘干法水分测定仪检定规程》,对模拟显示水分测定仪的测得值进行不确定度评定。     

基于阻隔性的卷烟内衬材料应用性能研究

为探讨不同阻隔性能卷烟内衬材料的实际应用性能,模拟了卷烟包装条件,采用烘箱法和静态顶空-气质联用法,分别评价了不同存储条件下内衬材料对烟丝含水率和2种外加致香成分含量的影响。结果显示,内衬材料的透氧透湿性能与烟丝含水率及致香成分含量之间没有明显的对应关系,实际应用性能基本不受透湿透氧性能的影响。     

Quality Assurance of Rice and Paddy Moisture Measurements in Thailand

A bilateral comparison in moisture measurement between the National Institute of Metrology Thailand (NIMT) and the Central Bureau of Weights and Measures (CBWM) was organized for quality assuring of rice and paddy moisture measurement in Thailand. The bilateral comparison was conducted by using the same batch of sample and moisture meter as transfer device. It consisted of two parts: moisture measurement in rice and in paddy. A rice moisture meter belonging to CBWM and rice standards prepared at the nominal moisture content of 10 %, 12 %, 14 % and 16 % at NIMT, were used for rice moisture comparison, while a paddy moisture meter belonging to NIMT and paddy standards prepared at the nominal moisture content of 12 %, 14 %, 16 % and 18 % at CBWM, were used for paddy moisture comparison. Both laboratories measured the moisture content of a sample by using the standard method in ISO 712 and used that sample to calibrate a moisture meter by means of the method based on ISO 7700-1. Since the moisture content of the sample can change during the comparison, correction values in moisture content between the standard value and the reading value from the moisture meter are used as calibration results for the comparison evaluation. For the rice moisture comparison, differences in the correction value measured by the two laboratories vary from 0.18 % to 0.46 %, with their combined comparison uncertainty of 0.37 % (\(\hbox {k}= 2)\). The main contribution to the difference comes from the standard values from both laboratories differing from 0.27 % to 0.53 %, as the rice standard was found to drift in moisture content less than 0.05 %. Similarly to the rice moisture comparison, differences in the correction value for the paddy moisture measurement range from 0.08 % to 0.56 % with the combined comparison uncertainty of 0.38  % (\(\hbox {k} = 2)\), whereas the stability in moisture content of the paddy sample at NIMT was found to be within 0.12 %.     

电场法土壤水分传感器研究

合适的土壤水分是作物良好生长和获得高产的条件之一,同时合理灌溉也是节约水资源的有效途径。基于电场法原理研制了测试土壤水分含量的传感器,并利用单片机实现自动控制。通过与烘干法对比研究,该传感器在土壤水分含量小于25%时实验误差小于5%,完全能满足农业生产需要。该传感器使用稳定安全,便于携带,能定点实时监测,精度较高,具有实用价值。     

Coaxial Contact Device

The coaxial device described can be used to connect both a microwave analyzer with standard coaxial measures for calibration of the analyzer and to connect microwave stripline circuits in measurements of their S-parameter. The proposed method of calibrating a device, using one or two rated stripline calibrators, transfers the results of the analyzer calibration by means of standard coaxial measures for measurement of S-parameters of stripline circuits.__________Translated from Izmeritel’naya Tekhnika, No. 5, pp. 65–68, May, 2005.     

基于传感技术的密封包装容器透湿度测试方法研究

针对吸湿剂称重法测试密封包装容器透湿度的缺点,提出了基于传感技术的密封包装容器透湿度测试方法,并设计了相应的试验,通过对某弹药包装箱的透湿度测试结果,验证了基于传感技术的包装容器透湿度测试方法的有效性。     

近红外漫反射式水果糖份含量的测量系统

基于近红外光谱技术而建立水果糖份含量的测量系统,主要包括FT-IR光谱仪、光纤漫 反射附件和数据采集卡。利用该系统对56个苹果糖份含量进行了预测试验, 结果为:标准校正误差为0.317,标准预测误差为0.487。该测量系统可以直接用于水果糖份含量的快速定量分析且预测精确度可达到95%。