共查询到17条相似文献,搜索用时 174 毫秒
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WS-Ⅰ型微量水份测定仪的研制 总被引:1,自引:0,他引:1
测定气体中痕量水份有露点仪、电解水份仪、压电水份仪和氧化铝水份仪等,各有优缺点;就灵敏度、连续性和操作繁简来说,以氧化铝水份仪为佳。1941年Kaller首先发表了氧化铝作介质的电容电阻湿度计。Cutting和Jason为现代氧化铝湿度计奠定了理论和实践方面的基础。美国Pana公司和爱尔兰Shaw公司已生产多种型号的商品仪器。而国内,未见有报导。WS—I型微量水份仪即根据氧化铝电容、电阻原理而设计並研制的仪器。可连续测定氢、氮、氩、空气等洁净气体中的水份,测量范围为-90℃~-20℃露点(相当于0.1~1000ppmv);测量准确度为±3℃露点;测量重复性为±1℃露点。 相似文献
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图像式露点测量仪器的功能开发 总被引:2,自引:0,他引:2
介绍了一种新型计量露点的标准仪器“图像第三式露点仪”的系统原理、软硬件构成及关键技术,该仪器经国家权威机构检定和若干单位试用表明,其性能稳定可靠,对提高部队乃至其行业的湿度露点的计量水平起到了积极的作用并且具有广泛的推广前景。 相似文献
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通过改善镜面冷却系统及光学探测装置扩大中温传递标准;通过在相对高露点温度下,使水和空气分离的冷凝回复系统,设计建立了新型高温传递标准,并做了误差分析。 相似文献
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玫瑰纯露是玫瑰提取精油后的重要副产物,是玫瑰精油的饱和水溶液,不仅含有植物水溶活性成分,同时也保留了精油的芳香成分,含有矿物养分,具有抗衰老、清除自由基,抗过敏、抗菌、消炎、防紫外线损伤等功效,是继玫瑰精油之后护肤领域重要的优势产品之一,但目前尚无关于其质量控制的标准,市售产品质量参差不齐。为此,该研究发展了一种胶束电动毛细管色谱法用于快速检测玫瑰纯露中的指标成分苯乙醇。在实验过程中分析物的定性通过标准物质加标及紫外吸收可见光谱图比对确认。实验对缓冲溶液中硼砂浓度、十二烷基硫酸钠(SDS)浓度、分离电压、进样条件、检测条件等影响检测的关键因素进行了考察。在优化条件(分离缓冲溶液10 mmol/L Na2B2O7+15 mmol/L SDS,分离电压+20 kV,检测波长208 nm,进样5 kPa, 5 s)下,玫瑰纯露样品在7 min内可以完成检测。本方法对苯乙醇检测的线性范围为0.50~1 000 mg/L,线性相关系数(r2)为0.999 0,检出限(LOD,S/N=3)为0.091 mg/L... 相似文献
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《Physics and Chemistry of Liquids》2012,50(2):167-172
Abstract Experimental measurements of dew point for binary nitrogen + water were carried out between 5.0105Pa and 100.2105 Pa and temperatures from 263.0 K to 283.7 K. The experimental method is based on the generation of wet gases by water condensation in two temperature-controlled condensers with continuous gas flow at specified pressures. 相似文献
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Quantitative Moisture Measurement with a Cavity Ring-down Spectrometer using Telecom Diode Lasers
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Moisture measurement is of great needs in semiconductor industry, combustion diagnosis, meteorology, and atmospheric studies. We present an optical hygrometer based on cavity ring-down spectroscopy (CRDS). By using different absorption lines of H2O in the 1.56 and 1.36 μm regions, we are able to determine the relative concentration (mole fraction) of water vapor from a few percent down to the 10-12 level. The quantitative accuracy is examined by comparing the CRDS hygrometer with a commercial chilled-mirror dew-point meter. The high sensitivity of the CRDS instrument allows a water detection limit of 8 pptv. 相似文献
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Kamila Klimaszewska Costel Sârbu Żaneta Polkowska Dariusz Lech Piotr Pasławski Stanisław Małek Jacek Namieśnik 《Central European Journal of Chemistry》2009,7(1):20-30
This paper presents the results of determination of selected characteristics (anions, cations, formaldehyde, hydrogen peroxide,
phenols, TC, TIC, TOC and metals) in dew samples collected in six different sites in Poland. The influence of local parameters
(e.g. wind speed, humidity) was investigated. Discriminant analysis was applied to the study of several dew samples collected from
different sampling sites covering six agglomerations in Poland. Discriminant function analysis was used not only for classifying
samples into different groups with a better than chance accuracy, but also for detecting the most important variables that
discern between the groups of samples considered. In this way it was possible to identify which ions or other physicochemical
features are responsible for the similarities or differences observed between different groups of dew samples. A good agreement
with their origin and location was observed. It is interesting to note that the classification of all samples was dominated
by pH, wind direction, pressure and temperature with a significant contribution of Na+ and Cl− ions.
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Bing Chen Jin Wang Yu R. Sun Peng Kang An-wen Liu Jian-ying Li Xiao-lei He Shui-ming Hu 《化学物理学报(中文版)》2015,28(4):440-444
Quantitative measurement of water vapor is essential in many fields including semiconduc-tor industry, combustion diagnosis, meteorology, and atmospheric studies. We present an optical hygrometer based on cavity ring-down spectroscopy. The instrument is high-vacuum compatible, self-calibrated by using the free-spectral-range of the ring-down cavity made of low-thermal-expansion Invar. Using a single tunable diode laser working at 1.39 μm, detection of trace water vapor in vacuum and in high-purity helium gas, and also determination of humidity at ambient conditions, have been demonstrated. It indicates that the instrument can be used to detect the partial pressure of water vapor in a very broad range from 10-7 Pa to 103 Pa. Such an optical hygrometer can be potentially applied as a primary moisture standard to determine the vapor pressures of water (ice) at low temperatures. 相似文献
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盐酸滴定碳酸钠第二化学计量点碳酸的浓度是溶液的pH值的计算依据,碳酸的浓度应该根据等物质的量反应原理,利用反应溶液的浓度具体计算得出,同时,应该明确说明计算时忽略碳酸的分解这一前提条件。 相似文献
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利用两点法确定了液体推进剂混胺中两组分——三乙胺乖二甲苯胺的电位滴定终点,并与常规的弧切作图法乖二阶微分法确定的滴定终点进行了配对t检验,显示结果之间不存在显著差异,或可予校正。两点法简单快速,结果可靠,特别适宜于大量样品的快速分析。 相似文献