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Establishment of a Determination Method for Fruit Texture in Chieh-qua Using Texture Analyzer
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作者 Ying WANG Xuan DU Na LIU 《Agricultural Biotechnology》 2026年第1期54-59,共6页
[Objectives]This study was conducted to establish a quantitative assessment method for the textural quality of chieh-qua fruit.[Methods]Using two modes of a texture analyzer,namely TPA(texture profile analysis)and pun... [Objectives]This study was conducted to establish a quantitative assessment method for the textural quality of chieh-qua fruit.[Methods]Using two modes of a texture analyzer,namely TPA(texture profile analysis)and puncture,the index data of the fruit were obtained by setting different trigger forces,deformation levels,test speeds,as well as puncture speeds and puncture depths.The data included TPA hardness,adhesiveness,springiness,cohesiveness,gumminess,chewiness,resilience,as well as skin hardness,skin toughness,flesh hardness,fracturability,and compactness.[Results]Different deformation levels had a significant impact on all parameters.Hardness,adhesiveness,gumminess and chewiness showed a trend of first increasing and then decreasing with the deformation level increasing.When the deformation level was 30%,the adhesiveness,gumminess and chewiness reached their maximum values.When the deformation level was 50%,TPA hardness reached its maximum.When the compression speed was 3 mm/s,the measured values of TPA hardness,adhesiveness,chewiness,and resilience were at their maximums.The skin hardness varied significantly under different trigger forces.When the trigger force was 15 g,the skin hardness reached a maximum value of 944.63 g,and the skin toughness,flesh hardness,fracturability,and compactness also reach their maximum values respectively.When the puncture depth was 12 mm,the flesh hardness and skin toughness reached their maximums of 682.51 g and 1.82 mm,respectively.In the TPA mode,the flesh hardness of chieh-qua showed an extremely significant negative correlation with springiness,cohesiveness,and resilience(P<0.01).The fruit fracturability detected by puncture had an extremely significant positive correlation with compactness(P<0.01).[Conclusions]The evaluation method for measuring chieh-qua texture by combining TPA and the puncture mode could accurately and quantitatively reflect the differences in the flesh texture quality of chieh-qua.The optimal parameters for texture measurement of chieh-qua fruit were determined as a 15 g trigger force with 50%deformation and a 3 mm/s compression speed in TPA mode,and a 15 g trigger force with a 12 mm puncture depth in puncture mode.Puncture speed was found to have no significant effect on the texture indices of chieh-qua. 展开更多
关键词 CHIEH-QUA Texture analyzer Texture quality Determination method
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Field observation of air-sea CO_(2) and H2O flux using the eddy covariance method based on 100 Hz gas analyzer in the Bohai and Yellow Seas
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作者 Tan Yu Yuhan Xia +8 位作者 Zhengli Qiu Bangyi Tao Yan Bai Xianqiang He Bing Chen Mingxing Li Yu Wang Qilan Zhang Chao Liang 《Acta Oceanologica Sinica》 2025年第7期161-176,共16页
Air-sea water vapor and CO_(2) flux observation experiments were carried out at the Yantai National Satellite Ocean Calibration Platform and the jetty at Monolithic Beach,Juehua Island,using a 100 Hz gas analyzer.The ... Air-sea water vapor and CO_(2) flux observation experiments were carried out at the Yantai National Satellite Ocean Calibration Platform and the jetty at Monolithic Beach,Juehua Island,using a 100 Hz gas analyzer.The observations were corrected by employing wild point rejection,linear detrending,delay correction,coordinate rotation,time matching,and Webb,Pearman,and Leuning(WPL)correction.The results of spectral analysis and a turbulence development adequacy data quality check showed that the overall observation data quality was good.The air-sea water vapor and CO_(2) flux results showed that the observation duration affected both the air-sea flux intensity and direction at different observation frequencies.At shorter observation durations,the air-sea flux values measured at 100 Hz were smaller than the 20 Hz measurements and had opposite directions.In addition,the WPL correction reduced the overall air-sea flux and partially minimized the effect of observation frequency on the air-sea flux intensity.These results showed that high-frequency observations showed more turbulence variations than low-frequency observations.This conclusion could promote an understanding of small-scale turbulence variations. 展开更多
关键词 eddy correlation method 100 Hz gas analyzer TDLAS air-sea flux observation frequency
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Accuracy verification and practice of simultaneous thermal analyzer
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作者 LI Haixia YANG Xiuhong +2 位作者 TIAN Liyan LUO Minting GUO Yanwen 《实验技术与管理》 北大核心 2025年第11期133-139,共7页
The accuracy of thermal analysis measurements is critical to analyze material properties correctly,making the improvement of measurement precision and proper uncertainty analysis of test results absolutely essential.A... The accuracy of thermal analysis measurements is critical to analyze material properties correctly,making the improvement of measurement precision and proper uncertainty analysis of test results absolutely essential.As a primary thermal analysis instrument,the simultaneous thermal analyzer(STA)has unique advantages,which combines the functionalities of thermogravimetric(TG)analyzersand differential scanning calorimeters(DSC).However,the absence of standard quality control procedures has resulted in poor measurement reproducibility,low accuracy,and inadequate traceability of analytical results.This study utilized a multi-point temperature calibration method based on national certified reference materials to reduce instrument temperature indication errors.On this basis,we innovatively established a comprehensive quality control system encompassing laboratory environmental control,standard method selection,instrument performance verification,reference material traceability,and uncertainty analysis,thereby achieving standardized operational procedures for thermal analysis measurement.Taking the"determination of initial melting temperature of unknown substances"as a representative case study,a component resolution model for thermal analysis test uncertainty was developed.Through systematic analysis of both the reference material-introduced component and measurement repeatability component,complete traceability of test results was achieved.This approach ensures data validity and enhances the accuracy of test results.This provides crucial technical support and practical reference for the standardization of thermal analysis measurement procedure and assessment of result reliability. 展开更多
关键词 thermal analysis accuracy simultaneous thermal analyzer standardized testing procedures instrument performance qualification method selection traceability analysis uncertainty analysis
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Application of Dynamic Linear Detecting Method in Data Processing of the Portable Blood Sugar Analyzer
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作者 Xiaohao Wang Ran Liu +2 位作者 Fei Tang Yangchun Yu Zhaoying Zhou 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期80-82,共3页
In this paper,a dynamic linear detecting method,that the non-linear coefficient NL% was led and the non-linearity of data were estimated continuously and dynamically and determined when NL% exceeded reference value (... In this paper,a dynamic linear detecting method,that the non-linear coefficient NL% was led and the non-linearity of data were estimated continuously and dynamically and determined when NL% exceeded reference value (5%),was used for data processing and could solve the problem caused by the phenomenon of substrate depleting occurred following the redox reaction in portable blood sugar analyzer.By contrast to the conventional end-point method,the dynamic linear detecting method is based on multipoint data collecting.Experiments of measuring the calibration glucose solution with 8 various concentrations from 50 mg/dl to 400 mg/dl were carried out with the analyzer developed by our group.The linear regression curve,whose correlation for the data was 0.9995 and the residual was 2.8080,were obtained.The obtained correlation,residual, and the computation workload are all fit for the portable blood sugar analyzer. 展开更多
关键词 data processing portable blood sugar analyzer dynamic linear detecting method
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Method of analyzing vibration characteristics of armature system of hermetically sealed electromagnetic relay
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作者 REN Wan-bin CUI Li +1 位作者 LUO Fu-biao ZHAI Guo-fu 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第3期434-438,共5页
Published research is minimal on vibration characteristics of hermetically sealed electromagnetic relay (EMR) ex- posed to mechanical environment. The vibration characteristics of armature system, link contact system ... Published research is minimal on vibration characteristics of hermetically sealed electromagnetic relay (EMR) ex- posed to mechanical environment. The vibration characteristics of armature system, link contact system with electromagnetic system will cause EMR malfunction. The nonlinear dynamics model of armature systems was studied by considering electro- magnetic attraction force and opposite mechanical force in this paper. Angular displacements of armature under different sinu- soidal vibration conditions are solved in order to obtain the failure mode result from armature system. Vibration tests showed the presented analyzing method is suitable for EMR. The conclusions are instructive for increasing vibration resistance of armature systems of EMR, and are significant for reliability design of switch apparatus. 展开更多
关键词 Hermetically sealed electromagnetic relay (EMR) Armature system Vibration characteristics analyzing method
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A Comparison between Neutron Activation Analysis and X-Ray Fluorescence Methods in Analyzing the Granite Samples
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作者 Hayder Salah Naeem Pegah Moradi Khaniabadi Eid Mahmoud Eid 《Journal of Chemistry and Chemical Engineering》 2013年第9期803-807,共5页
This study focused on the performance of where elements analysing techniques were used to detect the elements in granite stones. These techniques are NAA (neutron activation analysis) and XRF (X-ray fluorescence).... This study focused on the performance of where elements analysing techniques were used to detect the elements in granite stones. These techniques are NAA (neutron activation analysis) and XRF (X-ray fluorescence). They were applied to detect the elements in samples which had been chosen from different areas of Pulua Penang in Malaysia collected by geophysics group which helped to describe and identify the elements found in the granite stone that were used in the study procedures to control the analytical results. The integration of both methods has enabled the researcher to determine 40 elements in the samples. The numbers of elements detected by XRF analysis method are 12 elements (Ar, K, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn); while, the elements detected by NAA method have three folds of elements with XRF analysis method were 35 elements (Na, AI, Si, K, Ca, Sc,Ti, Mn, Fe, Co, Ga, Ce, As, Br, Rb, Zr, Sb, I, Cs, Ba, La, Nd, Sm, Eu,Tb, Dy, Yb, Lu, Hf, Ta, W, Au, Pa and Np). Seven common elements were detected in both techniques: K, Sc, Ti, V, Mn, Fe and Co. Si has a higher concentration in NAA technique which is 331.8 ppm. Sc has a lower concentration in XRF technique which is 0.25 ppm. Nd has a lower concentration in NAA technique which is 3.09 - 10-5 ppm. Finally, it is found that the NAA is better to detect the elements than XRF. 展开更多
关键词 Radiation science radiation physics NAA XRF analyzing methods.
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元素分析仪测定植物样品中全氮含量
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作者 刘小林 裴美乐 +3 位作者 莫凯敏 王子杰 陶柳君 彭君 《当代化工研究》 2026年第1期82-84,共3页
氮是植物核酸、蛋白质及叶绿素等关键组分的核心元素,全氮含量是评估植物营养与健康状况的重要指标。研究旨在验证元素分析仪测定植物全氮含量的准确性与适用性,并与传统凯氏定氮法进行对比分析。采用元素分析仪(基于杜马斯燃烧法)对植... 氮是植物核酸、蛋白质及叶绿素等关键组分的核心元素,全氮含量是评估植物营养与健康状况的重要指标。研究旨在验证元素分析仪测定植物全氮含量的准确性与适用性,并与传统凯氏定氮法进行对比分析。采用元素分析仪(基于杜马斯燃烧法)对植物样品进行全氮含量测定,通过计算相对误差与相对标准偏差(RSD)评价方法性能,并与凯氏定氮法进行精密度及功能对比。元素分析仪测定结果的相对误差最小为0.92%,RSD范围为0.2%~1.2%,表明其准确度高且精密度良好;与凯氏法相比,两者精密度相当,但元素分析仪检测速度更快,且能测定凯氏法无法检测的硝态氮,全氮检测结果更全面。元素分析仪具有高效、精准、绿色无污染的优势,尤其适用于含硝态氮样品的全氮分析,具有推广价值。 展开更多
关键词 植物全氮 元素分析仪 凯氏定氮法 杜马斯燃烧法
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惰气熔融-红外吸收法/热导法测定钽钨基合金中氧和氮含量的分析方法研究
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作者 刘瑞 王刚 李小阳 《硬质合金》 2026年第1期77-85,106,共10页
因钽钨基合金中,O、N元素含量偏高,会形成脆性氧化物或氮化物相,恶化合金的低温塑性,因此精准控制钽钨基合金中的O、N含量至关重要。为了准确掌握钽钨基合金中的O、N含量,本文利用惰性气体熔融-红外吸收法/热导法,研究检测过程中助熔剂... 因钽钨基合金中,O、N元素含量偏高,会形成脆性氧化物或氮化物相,恶化合金的低温塑性,因此精准控制钽钨基合金中的O、N含量至关重要。为了准确掌握钽钨基合金中的O、N含量,本文利用惰性气体熔融-红外吸收法/热导法,研究检测过程中助熔剂、称样量、分析功率和积分时间等实验参数,建立了惰气熔融-红外吸收法/热导法测定钽钨合金中O、N含量的方法。实验结果表明:称样量为0.070~0.120 g,脱气功率5.5 kW,分析功率5.0 kW,氧分析时间为35 s,氮分析时间为55 s时,可准确地检测出钽钨基合金中的O、N含量,O的方法测定下限确定为0.0010%,N的方法测定下限确定为0.0005%。按照实验方法对钽钨基合金样品中O、N含量进行测定,并进行加标回收试验,O的加标回收率为94.43%~99.17%,RSD<6%,N的加标回收率为97.29%~102.11%,RSD<10%。检测结果精度满足要求,可有效指导产线进行O、N元素的控制。 展开更多
关键词 氧氮仪 钽钨合金 红外吸收法 热导法
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空气质量检测系统中的臭氧分析与测试
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作者 窦柯 吕子啸 +1 位作者 闫兴钰 韩丙辰 《科技创新与生产力》 2026年第1期6-9,13,共5页
文章针对臭氧浓度监测需求,设计了一种基于紫外吸收法的臭氧分析仪,可应用于连续自动监测系统。该分析仪量程为0~500×10^(-9),最小显示单位0.1×10^(-9),七天零点漂移小于1×10^(-9),示值误差在±4%F.S.以内。设备采... 文章针对臭氧浓度监测需求,设计了一种基于紫外吸收法的臭氧分析仪,可应用于连续自动监测系统。该分析仪量程为0~500×10^(-9),最小显示单位0.1×10^(-9),七天零点漂移小于1×10^(-9),示值误差在±4%F.S.以内。设备采用双通道紫外光检测与周期切换通路的抗干扰设计,能有效应对常见气体如甲苯、二氧化硫、水蒸气的干扰影响。性能测试结果显示其零点噪声与最低检出限、干扰检测等指标均符合HJ654–2013标准要求。该仪器具备实时性强、操作简便、高精度与强抗干扰能力的特点,适用于多种现场环境中的臭氧连续监测任务。 展开更多
关键词 氧浓度 紫外光吸收法 臭氧分析仪 连续自动监测系统
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微粉化非诺贝特粒度及粒度分布研究
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作者 付志玲 杨楠楠 +3 位作者 刘佩 白秀秀 尚斌 李霞 《中国药业》 2026年第1期83-85,共3页
目的建立测定微粉化非诺贝特粒度的方法。方法进样前用5号标准药典筛进行预分散,检测仪器为Mastersizer 3000型激光粒度仪,检测方法为干法,颗粒类型为非球形,进样量为0.20 g,折射率为1.53,颗粒吸收率为0.01,背景测试时间为10 s,样品测... 目的建立测定微粉化非诺贝特粒度的方法。方法进样前用5号标准药典筛进行预分散,检测仪器为Mastersizer 3000型激光粒度仪,检测方法为干法,颗粒类型为非球形,进样量为0.20 g,折射率为1.53,颗粒吸收率为0.01,背景测试时间为10 s,样品测试时间为8 s,测量次数为1次,遮光度为1%~5%,分散气压为1.50 bar,振动进样速率为50%,文丘里管类型为标准文丘里管,料斗间隙为1.00 mm,分析模型为通用型。结果重复性、耐用性试验结果的RSD均小于8%。3批样品的累积粒度分布达到10%,50%,90%时对应的粒径(D_(10),D_(50),D_(90))分别为2.30~2.36μm、5.33~5.35μm、10.56~10.69μm。结论所建立的方法操作简单、快捷,能满足微粉化非诺贝特生产过程中的快速检测,且重复性、耐用性均良好,适用于该产品的粒度控制。 展开更多
关键词 非诺贝特 微粉化 激光粒度仪干法 粒度分布
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基于岭回归的后期扶持项目对水库移民增收影响分析方法
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作者 彭子威 《科学技术创新》 2026年第5期17-20,共4页
针对目前后期扶持项目投资对移民收入水平产生实际效果难以预测的问题,提出基于岭回归的水库移民后期扶持项目对其增收影响分析方法。以广东省15个地区后期扶持监测评估报告和当年度各地区的政府统计公报的数据为基础,构建后期扶持项目... 针对目前后期扶持项目投资对移民收入水平产生实际效果难以预测的问题,提出基于岭回归的水库移民后期扶持项目对其增收影响分析方法。以广东省15个地区后期扶持监测评估报告和当年度各地区的政府统计公报的数据为基础,构建后期扶持项目对水库移民增收影响的模型。结果表明:岭回归解决了传统方法中因素多重共线性问题且拟合优度R2更高,不同后期扶持项目对水库移民人均增收的影响存在显著差异,产业扶持和人力资本是移民增收的核心动力。岭回归方法可为后续后期扶持项目对水库移民增收影响分析提供参考。 展开更多
关键词 岭回归 拟合优度 因素多重共线性 增收影响分析方法
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A Rapid Method for Measuring Seed Protein Content in Cowpea (<i>Vigna unguiculata</i>(L.) Walp) 被引量:1
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作者 Yuejin Weng Ainong Shi +5 位作者 Waltram Second Ravelombola Wei Yang Jun Qin Dennis Motes David Octor Moseley Pengyin Chen 《American Journal of Plant Sciences》 2017年第10期2387-2396,共10页
Cowpea (Vigna unguiculata (L.) Walp), a legume crop that is grown in the worldwide, provides beneficial proteins for human consumption and animal feeding. In comparison, Rapid N analyzer as traditional method, has bee... Cowpea (Vigna unguiculata (L.) Walp), a legume crop that is grown in the worldwide, provides beneficial proteins for human consumption and animal feeding. In comparison, Rapid N analyzer as traditional method, has been widely used to measure protein content through the percentage of total nitrogen in the seed’s grounded powder. Near-Infrared Reflectance (NIR) has commonly been used to measure protein content in soybean seeds using whole grain without the need of seed grinding, which makes it possible to obtain fast results at a lower cost-per-analysis than the traditional combustion method. The specific objective of this study is to test a rapid method for measuring cowpea seed protein content by the NIR analyzer comparing to the traditional rapid N analyzer. A total of 240 cowpea genotypes were used in this study, including six seed coat colors, black, blackeye, browneye, cream, pinkeye, and red with 40 cowpea genotypes. The results showed that a linear relationship exists between the NIR analyzer and the Rapid N analyzer in the six different color groups. The correlation efficiency (r) between the seed protein contents from NIR and Rapid N was higher for pinkeye seed (r = 0.867), blackeye (0.771), cream (0.729), browneye (0.700), and red (0.623), respectively, but lower for black seeds, indicating that the NIR analyzer can be used to measure protein content for cowpea seeds with the five types of seed coat except black. Overview, the cowpea seed protein content measured from the NIR analyzer showed a little higher seed protein content. A series of regression models with different seed coat color have been built to adjust to protein content of colorful cowpea seeds from the NIR analyzer. But, it is not recommended to use for black color seeds due to a very low correlation efficiency (r) value with 0.184. 展开更多
关键词 COWPEA Seed PROTEIN CONTENT PROTEIN Measurement method Rapid N analyzer Near-Infrared Reflectance (NIR) Vigna unguiculata
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A TOTAL CONTENT X—RAY FLUORESCENCE METHOD FOR COPPER PROSPECTING
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作者 周四春 谢庭周 葛良全 《Nuclear Science and Techniques》 SCIE CAS CSCD 1992年第3期191-195,共5页
A new method is proposed to prospect copper deposits with portable XRF analyzer. The method is based on the close relation between Cu and the chalcophile elements or some other elements in the geochemical anomalies of... A new method is proposed to prospect copper deposits with portable XRF analyzer. The method is based on the close relation between Cu and the chalcophile elements or some other elements in the geochemical anomalies of a Cu deposit. Applications of the technique in Northeast China are presented. 展开更多
关键词 Portable X-RAY FLUORESCENCE analyzerS Total content X-RAY FLUORESCENCE method PROSPECTING for COPPER DEPOSITS
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Assessment of the Phylogenetic Affiliation Levels of Water Mite(Acari,Hydrachnidia)Species with the Elemental Analysis Method
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作者 Ferruh Asci Mustafa Ucar +1 位作者 Saban Kabak Muhlis Ozkan 《Advances in Bioscience and Biotechnology》 2015年第6期427-432,共6页
10 different species of water mites which are Georgella helvetica, Eylais extendens, Hydrachna globose, Hydrachna prosifera, Hydrachna skorikowi, Hydrodroma despiciens, Hydryphantes dispar, Limnesia fulgida, Eylais se... 10 different species of water mites which are Georgella helvetica, Eylais extendens, Hydrachna globose, Hydrachna prosifera, Hydrachna skorikowi, Hydrodroma despiciens, Hydryphantes dispar, Limnesia fulgida, Eylais setosa, Hydryphantes flexuosus were used in this study. The total masses of these species were measured as mg with the use of an elemental analyzer to calculate the percentage of the organic components of their structures. The achieved values were assessed separately for each species and element with the interpolation method. Out of these organic elements, the amount of C with an approximately value of 50% was the highest for all species while the amounts of S which was approximately 1% was determined as the lowest for almost all species. The observed values were discussed in terms of the systematic of water mites. 展开更多
关键词 Water Mites ACARI HYDRACHNIDIA Elemental analyzer Interpolation method
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基于频域扫描的表层土壤含水量检测算法
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作者 宋华军 刘旭 +2 位作者 田岳 任鹏 沈美丽 《电子器件》 2025年第4期950-954,共5页
土壤水是作物生长发育直接水源,土壤含水量是监测作物旱情的最重要的指标。目前土壤含水量检测算法无法满足大规模的监测需要,存在精度较低,易受天气、地表状况等因素影响的问题。微波测量方法能解决上述问题,但是当前该方法采用时域脉... 土壤水是作物生长发育直接水源,土壤含水量是监测作物旱情的最重要的指标。目前土壤含水量检测算法无法满足大规模的监测需要,存在精度较低,易受天气、地表状况等因素影响的问题。微波测量方法能解决上述问题,但是当前该方法采用时域脉冲,具有噪声大等问题。基于去噪声能力强的矢量网络分析仪采用频域扫描方法,使用菲涅尔反射系数进行反演,建立土壤含水量和介电常数关系模型。反演结果表明,不同含水量的土壤介电常数存在明显差别,得到的含水量的精确度能够满足设计要求。 展开更多
关键词 土壤含水量 介电常数 矢量网络分析仪 自由空间法
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基于临界流锐孔动态稀释的痕量氧分析仪校准装置及方法
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作者 于瑞祥 任逸尘 +4 位作者 刘旺旺 高艳秋 董翊 姜阳 魏王慧 《化学分析计量》 2025年第7期114-119,共6页
设计了一套基于临界流锐孔的动态稀释原理的痕量氧分析仪校准装置,用于痕量氧分析仪在0~1 000nmol/mol使用范围内的校准。介绍了临界流锐孔基本原理,验证了稀释装置中纯化器的性能,对稀释装置的稀释准确性进行了研究,建立了痕量氧分析... 设计了一套基于临界流锐孔的动态稀释原理的痕量氧分析仪校准装置,用于痕量氧分析仪在0~1 000nmol/mol使用范围内的校准。介绍了临界流锐孔基本原理,验证了稀释装置中纯化器的性能,对稀释装置的稀释准确性进行了研究,建立了痕量氧分析仪的校准方法,实现了一次连接即可完成零点及量程点的校准,并对校准方法的示值误差进行了不确定度评定。结果表明,3个校准点示值误差的不确定度与被评定仪器的最大允许误差(±15%)之比不大于1/3,证明以稀释装置建立的校准方法对痕量氧分析仪在0~1 000 nmol/mol使用范围内的校准是合理的。该校准装置与方法可实现现场校准服务功能,为企业痕量氧分析仪的计量校准工作提供了重要的技术参考与实践依据。 展开更多
关键词 临界流锐孔 动态稀释 痕量氧分析仪 校准装置 校准方法 不确定度评定
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天然气行业几种典型露点仪校准方法适应性分析
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作者 李阳 《石油石化节能与计量》 2025年第4期57-62,共6页
天然气中的水含量,是衡量天然气质量的重要指标。在管道输送过程中,天然气水含量越高,越易在管道中形成水合物,在管道低洼处聚集,既影响输气效率,又易造成管道腐蚀。为防止天然气中的水分及水合物在天然气管输过程中产生的不利影响,越... 天然气中的水含量,是衡量天然气质量的重要指标。在管道输送过程中,天然气水含量越高,越易在管道中形成水合物,在管道低洼处聚集,既影响输气效率,又易造成管道腐蚀。为防止天然气中的水分及水合物在天然气管输过程中产生的不利影响,越来越多的输气场站安装了在线露点监测设备,常用的在线露点分析仪大部分采用阻容法、光纤法、电解法等工作原理。但目前针对该类型设备尚无相关的检定规程,仅能依据JJF 1272—2011《阻容法露点湿度计校准规范》开展校准工作。在现有的校准规范基础上,深入研究几种典型露点分析仪的校准方法,对不同型号、不同品牌、不同原理的露点分析仪的校准工作进行总结,并对工作中遇到的问题给出合理建议。 展开更多
关键词 水露点分析仪 阻容法 光纤法 电解法 校准规范 校准方法
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BOD-Q水质测定仪的研制及其实验教学应用
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作者 宋诚 王厦 刘鸿 《大学化学》 2025年第2期89-96,共8页
生化需氧量(BOD)是水污染控制领域科学研究中关键的数据指标。传统BOD基于溶氧耗量的检测方法,具有测试周期长、结果误差大、重现性差、操作复杂等问题,严重制约着水环境水生态领域的发展和实验教学的应用。本文提出一种BOD检测的新原... 生化需氧量(BOD)是水污染控制领域科学研究中关键的数据指标。传统BOD基于溶氧耗量的检测方法,具有测试周期长、结果误差大、重现性差、操作复杂等问题,严重制约着水环境水生态领域的发展和实验教学的应用。本文提出一种BOD检测的新原理、新方法、新仪器,阐述了一项原始创新科学仪器——“BOD-Q水质测定仪”的研制及其实验教学应用,结果表明,该仪器将BOD检测时间从传统的5天缩短至0.5–5小时,检测误差≤10%,将该仪器引入实验教学中可丰富教学内容,提高教学质量。 展开更多
关键词 BOD 微生物库伦法 BOD-Q水质测定仪 原始创新科学仪器 实验教学
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铀矿石中有机碳测量结果的不确定度评定
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作者 张建梅 邓长生 《山东化工》 2025年第14期153-154,179,共3页
为了对高频红外吸收法测定铀矿石中有机碳含量的测量结果进行不确定度评定,本文通过建立数学模型,分析了不确定度的来源,包括样品称量、标准工作曲线测量结果、空白试验及重复测量所引入的不确定度。通过计算得到了各个不确定度分量,并... 为了对高频红外吸收法测定铀矿石中有机碳含量的测量结果进行不确定度评定,本文通过建立数学模型,分析了不确定度的来源,包括样品称量、标准工作曲线测量结果、空白试验及重复测量所引入的不确定度。通过计算得到了各个不确定度分量,并合成得到了标准不确定度和扩展不确定度。结果表明,当碳含量为4.82%时,测量结果的扩展不确定度为0.354%(k=2)。对各不确定度分量进行比较,不确定度主要来源为样品称量和曲线拟合。 展开更多
关键词 铀矿石 有机碳 不确定度评定 红外吸收法 高频红外碳硫分析仪
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密度计法与激光粒度仪法在颗粒分析试验中的误差分析 被引量:1
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作者 吕龙龙 游耀星 +2 位作者 李学丰 李霄洋 伏映鹏 《工程地质学报》 北大核心 2025年第4期1499-1509,共11页
探究颗粒分析试验方法的误差对精准测定土的粒径分布具有重要意义。采用甲、乙密度计和激光粒度仪对包括风积砂、粉细砂、沉积砂、黄土、海相黏土、湖积黏土的18种土样进行了颗粒分析试验,评价了两类试验方法的稳定性,探究了不同方法测... 探究颗粒分析试验方法的误差对精准测定土的粒径分布具有重要意义。采用甲、乙密度计和激光粒度仪对包括风积砂、粉细砂、沉积砂、黄土、海相黏土、湖积黏土的18种土样进行了颗粒分析试验,评价了两类试验方法的稳定性,探究了不同方法测试细粒含量的相关性和液限、矿物成分对试验结果的影响,并提出了一种基于筛分法对激光粒度仪所得砂土、黄土级配结果优化的修正方法。结果表明:激光粒度仪法测砂粒含量较筛分法偏低,修正可以提高细粒含量测定和土样分类的准确性;激光粒度仪法与密度计法在粉粒含量测试上具有良好的线性相关性,而砂粒、黏粒含量相关性较差;颗粒分析试验方法稳定性从优到劣依次为激光粒度仪法、甲密度计法、乙密度计法,不同液限的黄土适用的密度计种类不同;激光粒度仪法与密度计法的差异受矿物相对密度和黏土矿物含量共同影响。 展开更多
关键词 密度计法 激光粒度仪 粒径级配 矿物含量 误差分析
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