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Simplified quantitative analysis method and its application in the insitu synthesized copper-based azide chips
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作者 Jie Ren Yunfeng Li +3 位作者 Mingyu Li Xingyu Wu Jiabao Wang Qingxuan Zeng 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期309-316,共8页
Copper-based azide(Cu(N_(3))2 or CuN_(3),CA)chips synthesized by in-situ azide reaction and utilized in miniaturized explosive systems has become a hot research topic in recent years.However,the advantages of in-situ ... Copper-based azide(Cu(N_(3))2 or CuN_(3),CA)chips synthesized by in-situ azide reaction and utilized in miniaturized explosive systems has become a hot research topic in recent years.However,the advantages of in-situ synthesis method,including small size and low dosage,bring about difficulties in quantitative analysis and differences in ignition capabilities of CA chips.The aim of present work is to develop a simplified quantitative analysis method for accurate and safe analysis of components in CA chips to evaluate and investigate the corresponding ignition ability.In this work,Cu(N_(3))2 and CuN_(3)components in CA chips were separated through dissolution and distillation by utilizing the difference in solubility and corresponding content was obtained by measuring N_(3)-concentration through spectrophotometry.The spectrophotometry method was optimized by studying influencing factors and the recovery rate of different separation methods was studied,ensuring the accuracy and reproducibility of test results.The optimized method is linear in range from 1.0-25.0 mg/L,with a correlation coefficient R^(2)=0.9998,which meets the requirements of CA chips with a milligram-level content test.Compared with the existing ICP method,component analysis results of CA chips obtained by spectrophotometry are closer to real component content in samples and have satisfactory accuracy.Moreover,as its application in miniaturized explosive systems,the ignition ability of CA chips with different component contents for direct ink writing CL-20 and the corresponding mechanism was studied.This study provided a basis and idea for the design and performance evaluation of CA chips in miniaturized explosive systems. 展开更多
关键词 Copper-based azide chips SPECTROPHOTOMETRY Separation method quantitative analysis Ignition ability
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Improvements to the fuzzy mathematics comprehensive quantitative method for evaluating fault sealing 被引量:4
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作者 Da-Wei Dong Ji-Yan Li +2 位作者 Yong-Hong Yang Xiao-Lei Wang Jian Liu 《Petroleum Science》 SCIE CAS CSCD 2017年第2期276-285,共10页
Fuzzy mathematics is an important means to quantitatively evaluate the properties of fault sealing in petroleum reservoirs.To accurately study fault sealing,the comprehensive quantitative evaluation method of fuzzy ma... Fuzzy mathematics is an important means to quantitatively evaluate the properties of fault sealing in petroleum reservoirs.To accurately study fault sealing,the comprehensive quantitative evaluation method of fuzzy mathematics is improved based on a previous study.First,the single-factor membership degree is determined using the dynamic clustering method,then a single-factor evaluation matrix is constructed using a continuous grading function,and finally,the probability distribution of the evaluation grade in a fuzzy evaluation matrix is analyzed.In this study,taking the F1 fault located in the northeastern Chepaizi Bulge as an example,the sealing properties of faults in different strata are quantitatively evaluated using both an improved and an un-improved comprehensive fuzzy mathematics quantitative evaluation method.Based on current oil and gas distribution,it is found that our evaluation results before and after improvement are significantly different.For faults in"best"and"poorest"intervals,our evaluation results are consistent with oil and gas distribution.However,for the faults in"good"or"poor"intervals,our evaluation is not completelyconsistent with oil and gas distribution.The improved evaluation results reflect the overall and local sealing properties of target zones and embody the nonuniformity of fault sealing,indicating the improved method is more suitable for evaluating fault sealing under complicated conditions. 展开更多
关键词 Fault sealing property Fuzzy mathematics Dynamic clustering method quantitative study
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Study of a Quantitative Fluorescence Method for Interleukin 2 Receptor of Mononuclear Cell in Normal Human Peripheral Blood
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作者 郭明秋 骆抗先 +2 位作者 王金锐 丁生大 李少钦 《Journal of Medical Colleges of PLA(China)》 CAS 1989年第1期41-44,共4页
A quantitative method using fluorescence spectro-photometer to detect theinterleukin 2 reocptor (IL 2R) on the surface of mononuclear cells in normal humanperipheral blood is described. For expression of IL 2R, the ... A quantitative method using fluorescence spectro-photometer to detect theinterleukin 2 reocptor (IL 2R) on the surface of mononuclear cells in normal humanperipheral blood is described. For expression of IL 2R, the optimum conoentration of PHA andCon A were 100 μg/ml and 10 μg/ml respectively. The PHA induced effect on mononuclear cellswas better than Con A induced one. The peak value of IL 2R cxpression was at the 24th h afterstimulation The optimum dilution of the first antibody (anti-Tac) was 1: 50, while the dilution ofthe second antibody(fluorescein conjugated rabbit anti-mousc IgG) was 1: 32 Their optimumincubation period was 20 and 10 min repectively. The concentration of fluorcscein-conjugatedantibody per 1×10<sup>6</sup> mononuclear cells from the same normal human peripheral blood was5.22±0.45×10<sup>-10</sup> mol, and the coefficient of variation was 8. 6%. The concentration offluorescein-conjugated antibody per 1×10<sup>6</sup>PBMC from five healthy individuals was 4. 8±0. 97×10<sup>-10</sup> mol Therefore this assay system is stable and quite reproducible. 展开更多
关键词 INTERLEUKIN 2 RECEPTOR MONONUCLEAR CELL quantitative immunofluoresoence method
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Comparison of Analyses of Genetic Structure among Chinese Indigenous Chicken Breeds using Distance-based and Model-based Methods
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作者 LI Hui-fang CHEN Kuan-wei +5 位作者 HAN Wei ZHANG Xue-yu GAO Yu-shi CHEN Guo-hong ZHU Yun-fen WANG Qiang 《畜牧兽医学报》 CAS CSCD 北大核心 2009年第S1期8-12,共5页
The Nei's improved genetic distance(DA)and gene flow(Nm)were measured using sixteen microsatellite markers.Dendograms based on DA genetic distance using the neighbor-joining(NJ)method and STRUCTURE program were co... The Nei's improved genetic distance(DA)and gene flow(Nm)were measured using sixteen microsatellite markers.Dendograms based on DA genetic distance using the neighbor-joining(NJ)method and STRUCTURE program were constructed to analyze the genetic structure and relationship among 10 Chinese indigenous chicken breeds.The results showed that dendograms of DA genetic distance using the NJ method divided the 10 chicken breeds into two main clusters;one consisted of breeds of low weight body(CHA,TTB,XIA,GUS and BAI),the other contained heavier breeds(LAN,DAG,YOU,XIS and LUY).In the lighter breeds,TIB and CHA clustered together,as did XIA and GUS.In the heavier breeds,XIS and LUY was clustered together in one branch,but LAN,DAG and YOU clustered in independent branches.The results were consistent with Nm estimates among the 10 indigenous chicken breeds.The STRUCTURE program properly inferred the presence of genetic structure despite not pre-defining the origin of individuals.The genetic cluster inferred by STRUCTURE was basically the same as that from the DA distance clustering method.An advantage of the STRUCTURE program was its ability to identify the migrants and admixed individuals in the 10 chicken populations;this could not be achieved by use of the DA distance clustering method. 展开更多
关键词 microsatellite CHINESE chicken BREEDS Distance-based CLUSTERING method model-based CLUSTERING method
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Real-time quantitative optical method to study temperature dependence of crack propagation process in colloidal photonic crystal film
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作者 林冬风 徐余颛 +4 位作者 石将建 张瑜 罗艳红 李冬梅 孟庆波 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期518-523,共6页
A real-time quantitative optical method to characterize crack propagation in colloidal photonic crystal film(CPCF)is developed based on particle deformation models and previous real-time crack observations. The crac... A real-time quantitative optical method to characterize crack propagation in colloidal photonic crystal film(CPCF)is developed based on particle deformation models and previous real-time crack observations. The crack propagation process and temperature dependence of the crack propagation rate in CPCF are investigated. By this method, the crack propagation rate is found to slow down gradually to zero when cracks become more numerous and dense. Meanwhile, with the temperature increasing, the crack propagation rate constant decreases. The negative temperature dependence of the crack propagation rate is due to the increase of van der Waals attraction, which finally results in the decrease of resultant force. The findings provide new insight into the crack propagation process in CPCF. 展开更多
关键词 colloidal photonic crystal crack propagation TEMPERATURE real-time quantitative optical method
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Improvement of quantitative analysis of molybdenum element using PLS-based approaches for laser-induced breakdown spectroscopy in various pressure environments 被引量:3
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作者 Jiamin LIU Ding WU +4 位作者 Cailong FU Ran HAI Xiao YU Liying SUN Hongbin DING 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第3期140-147,共8页
An experimental setup has been designed and realized in order to optimize the characteristics of laser-induced breakdown spectroscopy system working in various pressure environments. An approach combined the normaliza... An experimental setup has been designed and realized in order to optimize the characteristics of laser-induced breakdown spectroscopy system working in various pressure environments. An approach combined the normalization methods with the partial least squares(PLS) method are developed for quantitative analysis of molybdenum(Mo) element in the multi-component alloy,which is the first wall material in the Experimental Advanced Superconducting Tokamak. In this study, the different spectral normalization methods(total spectral area normalization,background normalization, and reference line normalization) are investigated for reducing the uncertainty and improving the accuracy of spectral measurement. The results indicates that the approach of PLS based on inter-element interference is significantly better than the conventional PLS methods as well as the univariate linear methods in the various pressure for molybdenum element analysis. 展开更多
关键词 laser induced BREAKDOWN spectroscopy MOLYBDENUM VACUUM NORMALIZATION partial least SQUARES method quantitative analysis
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Quantitative Measurement of the Proportions of High-Order Harmonics for the 4B7B Soft-X-Ray Source at Beijing Synchrotron Radiation Facility 被引量:2
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作者 朱托 尚万里 +9 位作者 张文海 杨家敏 熊刚 赵阳 况龙钰 赵屹东 郑雷 崔明启 唐坤马 陈燕 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第12期1194-1196,共3页
A transmission grating coupled with an X-ray charge coupled device (CCD) is used to quantitatively measure the proportion of high-order harmonics of the soft-X-ray source of beam line 4B7B. The results show that the... A transmission grating coupled with an X-ray charge coupled device (CCD) is used to quantitatively measure the proportion of high-order harmonics of the soft-X-ray source of beam line 4B7B. The results show that the monochromatic X-ray has third-order and second-order harmonics. The proportion of second-order harmonic of 4B7B is less than 9.0% and the third- order harmonic is below 0.7% when no suppressing method is applied. When suppression methods are used, the proportion of second-order harmonic is less than 1.7% and the third-order harmonic is ignorable. 展开更多
关键词 quantitative measurement high-order harmonics suppressing method
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Quantitative analysis modeling for the Chem Cam spectral data based on laser-induced breakdown spectroscopy using convolutional neural network 被引量:1
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作者 Xueqiang CAO Li ZHANG +3 位作者 Zhongchen WU Zongcheng LING Jialun LI Kaichen GUO 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第11期81-90,共10页
Laser-induced breakdown spectroscopy(LIBS)has been applied to many fields for the quantitative analysis of diverse materials.Improving the prediction accuracy of LIBS regression models is still of great significance f... Laser-induced breakdown spectroscopy(LIBS)has been applied to many fields for the quantitative analysis of diverse materials.Improving the prediction accuracy of LIBS regression models is still of great significance for the Mars exploration in the near future.In this study,we explored the quantitative analysis of LIBS for the one-dimensional Chem Cam(an instrument containing a LIBS spectrometer and a Remote Micro-Imager)spectral data whose spectra are produced by the Chem Cam team using LIBS under the Mars-like atmospheric conditions.We constructed a convolutional neural network(CNN)regression model with unified parameters for all oxides,which is efficient and concise.CNN that has the excellent capability of feature extraction can effectively overcome the chemical matrix effects that impede the prediction accuracy of regression models.Firstly,we explored the effects of four activation functions on the performance of the CNN model.The results show that the CNN model with the hyperbolic tangent(tanh)function outperforms the CNN models with the other activation functions(the rectified linear unit function,the linear function and the Sigmoid function).Secondly,we compared the performance among the CNN models using different optimization methods.The CNN model with the stochastic gradient descent optimization and the initial learning rate?=?0.0005 achieves satisfactory performance compared to the other CNN models.Finally,we compared the performance of the CNN model,the model based on support vector regression(SVR)and the model based on partial least square regression(PLSR).The results exhibit the CNN model is superior to the SVR model and the PLSR model for all oxides.Based on the above analysis,we conclude the CNN regression model can effectively improve the prediction accuracy of LIBS. 展开更多
关键词 laser-induced breakdown spectroscopy convolutional neural network activation function optimization method quantitative analysis
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Quantitative Testing of Defect for Gun Barrels
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作者 王长龙 纪凤珠 +1 位作者 王瑾 陈正阁 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第1期7-10,共4页
The magnetic flux leakage (MFL) method is commonly used in the nondestructive evaluation (NDE) of gun barrels. The key point of MFL testing is to estimate the crack geometry parameters based on the measured signal. Th... The magnetic flux leakage (MFL) method is commonly used in the nondestructive evaluation (NDE) of gun barrels. The key point of MFL testing is to estimate the crack geometry parameters based on the measured signal. The analysis of magnetic leakage fields can be obtained by solving Maxwell’s equations using finite element method (FEM). The radial component of magnetic flux density is measured in MFL testing. The peak-peak value, the separation distance between positive and negative peaks of signal and the lift-off value of Hall-sensor are used as the main features of every sample. This paper establishes the multi-regression equations related to the width (the depth) of crack and the main characteristic values. The regression model is tested by use of the magnetic leakage data. The experimental results indicate that the regression equations can accurately predict the 2-D defect geometry parameters and the MFL quantitative testing can be achieved. 展开更多
关键词 火炮身管 材料缺陷 MFL法 定量测试 有限元
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考虑潜在溃坝的水库大坝运行成本和收益量化方法
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作者 葛巍 孙贺强 +3 位作者 李永闯 景来红 李宗坤 王建有 《郑州大学学报(工学版)》 CAS 北大核心 2025年第1期59-66,共8页
针对水库大坝逐渐老化、自身风险和运行成本不断增加的情况,为了进一步明确水库大坝运行的经济性,构建了一种考虑潜在溃坝损失作用下的水库大坝运行综合成本与综合收益量化模型。首先,综合考虑大坝潜在溃坝的影响,根据ISM理论明确了水... 针对水库大坝逐渐老化、自身风险和运行成本不断增加的情况,为了进一步明确水库大坝运行的经济性,构建了一种考虑潜在溃坝损失作用下的水库大坝运行综合成本与综合收益量化模型。首先,综合考虑大坝潜在溃坝的影响,根据ISM理论明确了水库大坝运行成本与收益影响因素之间的相互作用关系,确定了水库大坝运行综合成本与综合收益量化指标;其次,基于DEMATEL法分析了各因素之间的相互作用程度,明确了各成本与收益指标之间相对重要程度;最后,结合技术经济学理论,计算了潜在溃坝损失作用下的水库大坝运行综合成本和综合收益。将所提模型应用于国内某水库,计算了该水库的运行综合成本和综合收益,并对其经济性进行了分析,结果表明:在考虑潜在溃坝损失的情况下,该水库运行综合成本为743.62万元,综合收益为10911.83万元,收益成本比为14.67,运行综合收益远大于运行综合成本,创收能力良好,经济效益显著。 展开更多
关键词 水库大坝 成本收益 量化方法 自身风险 溃坝
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郫县豆瓣感官轮及定量描述剖面建立 被引量:2
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作者 陈厚银 钟葵 +7 位作者 云振宇 史波林 汪厚银 张瑶 张丽涵 何晓宁 项雅科 赵镭 《食品科学》 EI CAS 北大核心 2025年第3期179-186,共8页
为探究中国地理标志产品郫县豆瓣的感官特性,通过感官评价小组构建郫县豆瓣的感官轮及定量描述剖面。采用中心点剖面法结合几何平均值对市面上21款豆瓣产品进行感官描述词开发,构建包括外观、基本味、香气、风味和质地5个维度共计53个... 为探究中国地理标志产品郫县豆瓣的感官特性,通过感官评价小组构建郫县豆瓣的感官轮及定量描述剖面。采用中心点剖面法结合几何平均值对市面上21款豆瓣产品进行感官描述词开发,构建包括外观、基本味、香气、风味和质地5个维度共计53个感官描述词。进一步结合多元统计方法复选出23个感官描述词并建立相应的强度参比样,开展不同种类和等级郫县豆瓣感官品质的定量描述评价。结果表明,郫县传统豆瓣酱香、辣香更强、质地偏黏,可见性(蚕豆瓣)、硬度更大。相比传统豆瓣,郫县红油豆瓣颜色偏红褐色,具有更强的油香、香料香、湿润性和油味等特性。随等级增加,郫县豆瓣的酱香、豆豉味等特征更突出,滋味更加醇厚。本研究可为郫县豆瓣的感官品质评价、产品质量控制及改进提供基础数据和评价方法参考。 展开更多
关键词 郫县豆瓣 感官描述词 多元分析方法 感官轮 定量描述剖面
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肉鸡屠宰及零售环节沙门氏菌污染的定性和定量检测方法比较
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作者 张思宇 刘俊辉 +11 位作者 王娟 王琳 刘娜 张喜悦 宋时萍 赵建梅 黄秀梅 高玉斌 曲志娜 王君玮 赵格 黄保续 《中国动物检疫》 2025年第3期113-118,共6页
为确定检测鸡肉中沙门氏菌污染率和污染量的最优方法,采集棉拭子和胴体/产品洗液样品,分别采用棉拭子培养法、胴体/产品洗液培养法、胴体/产品洗液最大可能数法(MPN)以及胴体/产品洗液MPN法联合荧光PCR法(qPCR-MPN法)对沙门氏菌检出率... 为确定检测鸡肉中沙门氏菌污染率和污染量的最优方法,采集棉拭子和胴体/产品洗液样品,分别采用棉拭子培养法、胴体/产品洗液培养法、胴体/产品洗液最大可能数法(MPN)以及胴体/产品洗液MPN法联合荧光PCR法(qPCR-MPN法)对沙门氏菌检出率进行比较,并利用胴体/产品洗液MPN法和qPCR-MPN法对沙门氏菌污染量进行比较。定性检测结果显示:q PCR-MPN法对沙门氏菌的检出率最高(84%),其次是胴体/产品洗液MPN法(80%)、胴体/产品洗液培养法(60%)和棉拭子培养法(28%),不同方法间的检出率具有统计学差异(P<0.05);以胴体/产品洗液培养法为标准,qPCR-MPN法和胴体/产品洗液MPN法的敏感性均为100%,一致性均>80%,但胴体/产品洗液MPN法的特异性较高。定量检测结果显示:qPCR-MPN法检测出的沙门氏菌污染量高于胴体/产品洗液MPN法。结果说明:在同时需要定性和定量数据时,可选择胴体/产品洗液MPN法;qPCR-MPN法与胴体/产品洗液MPN法一致性好,且检出的沙门氏菌污染量更高,在定量检测时可选择,但应注意假阳性风险。 展开更多
关键词 沙门氏菌 肉鸡 定性检测 定量检测 方法比较
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纺织品中石墨烯检测方法的研究进展
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作者 龚婕 周兆懿 贾凯凯 《针织工业》 北大核心 2025年第2期90-94,共5页
介绍纺织品中石墨烯的主要定性和定量检测方法。定性检测方法主要有扫描电镜法、透射电镜法、拉曼光谱法、原子力显微镜法和X射线衍射法。定量检测方法主要有元素分析法和热重分析法。通过比较各种定性检测方法,可知将纺织品中的石墨烯... 介绍纺织品中石墨烯的主要定性和定量检测方法。定性检测方法主要有扫描电镜法、透射电镜法、拉曼光谱法、原子力显微镜法和X射线衍射法。定量检测方法主要有元素分析法和热重分析法。通过比较各种定性检测方法,可知将纺织品中的石墨烯材料有效地分散和提取,并以透射电镜法为主要定性鉴别方法,辅以拉曼光谱法、扫描电镜法、原子力显微镜法或X射线衍射法,可形成一套高效普适的定性方法。然而定量检测方法还无法做到纺织品中石墨烯和石墨的准确定量,有待完善。 展开更多
关键词 石墨烯 纺织品 检测方法 定性检测 定量检测
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微量生物炭表面酸性官能团质量摩尔浓度定量分析方法
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作者 李崯雪 崔邴晗 +3 位作者 尚宏儒 曹永娜 程泽斌 于艳玲 《哈尔滨工业大学学报》 北大核心 2025年第2期65-72,共8页
表面官能团是生物炭的重要组成部分,其种类与数量对生物炭的性质、性能和应用有很大影响。现有碳材料表面官能团定量分析主要方法为Boehm滴定法,该方法耗炭量大、操作步骤多、耗时长。为此,通过构建质子消耗模型、编写Python程序、进行... 表面官能团是生物炭的重要组成部分,其种类与数量对生物炭的性质、性能和应用有很大影响。现有碳材料表面官能团定量分析主要方法为Boehm滴定法,该方法耗炭量大、操作步骤多、耗时长。为此,通过构建质子消耗模型、编写Python程序、进行酸碱滴定实验、调试模型参数,建立一种微量生物炭表面官能团质量摩尔质量摩尔浓度定量分析方法,能够快速测量微量生物炭的表面官能团质量摩尔浓度与对应的酸解离常数p K_(a)。通过调整参数、训练模型,分析此方法适用的生物炭质量范围,发现测试样品质量为50 mg时模型的均方误差E_(MS)<0.002,迭代次数设置为20000时模型的E_(MS)<0.001,表明测量结果准确度较高。该方法测定的生物炭表面官能团总量与Boehm滴定法的相对误差在2%以内,且生物炭用量缩减95%、测量时间缩短10 h以上、实验操作步骤大幅简化,满足生物炭表面官能团定量分析微量、快速的技术需求。 展开更多
关键词 生物炭 表面官能团 酸碱滴定 定量分析方法
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城市公共绿色空间景观感知评价与量化方法研究综述
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作者 许烁钰 李芝也 邓梭梭 《城市建筑》 2025年第4期18-21,共4页
城市公共绿色空间景观感知评价对于改善城市人居环境具有重要意义。目前国内相关研究起步较晚,厚积薄发,研究方法日趋多元,但缺少对已有方法的系统梳理。因此文章通过对国内外相关文献的整理归纳,从现有研究的研究目标、研究对象和目标... 城市公共绿色空间景观感知评价对于改善城市人居环境具有重要意义。目前国内相关研究起步较晚,厚积薄发,研究方法日趋多元,但缺少对已有方法的系统梳理。因此文章通过对国内外相关文献的整理归纳,从现有研究的研究目标、研究对象和目标人群、数据来源与量化方法三个方面对城市公共绿色空间景观感知评价与量化方法进行梳理,分析研究现状和未来发展可能,为之后的研究提供参考。 展开更多
关键词 城市公共绿色空间 景观感知 评价方法 量化方法 研究进展
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烟用纸张溶剂残留检测影响因素分析
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作者 余桢婷 康金岭 +4 位作者 刘瑱 覃耀 黄啟华 谢伟强 唐芳丽 《科技创新与应用》 2025年第9期76-79,共4页
为研究影响烟用纸张溶剂残留检测的因素,利用烟草行业标准YC/T207—2014《烟用纸张中溶剂残留的测定顶空-气相色谱/质谱联用法》中的方法,分析平行样差异、留存时间、制样位置、裁样数量和仪器定量方法 5个因素对烟用纸张溶剂残留26种... 为研究影响烟用纸张溶剂残留检测的因素,利用烟草行业标准YC/T207—2014《烟用纸张中溶剂残留的测定顶空-气相色谱/质谱联用法》中的方法,分析平行样差异、留存时间、制样位置、裁样数量和仪器定量方法 5个因素对烟用纸张溶剂残留26种挥发性有机物含量影响。结果表明,(1)通过对比5个平行样的溶剂残留物质含量可知,平行样差异小,其含量相对平均偏差均未超过10%。(2)留存时间越长会导致溶剂残留挥发情况越严重,在第5天和10天,变化最为明显。其中,甲苯、乙酸正丙酯最高损失量可以超过40%。(3)不同制样位置的裁剪纸张印刷图案不同,油墨的不均匀会导致不同位置样品的含量相对平均偏差超过10%。(4)标准曲线回归系数在0.995以上对物质定量影响较小。曲线必须为线性且强制过原点,尤其是含量较低的物质,对数据影响较大甚至造成误判。(5)裁样数量的不同并不会明显影响溶剂残留的含量,当裁剪纸张为2张时,溶剂残留物质浓度最高。 展开更多
关键词 烟用纸张 挥发性有机化合物 顶空-气相色谱/质谱联用法 溶剂残留检测 定量方法
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煤质对水煤浆导热系数的影响研究
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作者 常家瑞 刘卫东 +1 位作者 刘彬超 赵辉 《煤质技术》 2025年第2期61-66,共6页
煤气化是煤炭清洁高效利用的重要途径,水煤浆预热是提高煤气化能源利用效率的关键之一,基于导热系数是介质流动换热的重要基础参数且表征着其在稳态导热过程的导热能力,针对我国煤炭多样品种的煤质对水煤浆导热系数的影响研究具有现实... 煤气化是煤炭清洁高效利用的重要途径,水煤浆预热是提高煤气化能源利用效率的关键之一,基于导热系数是介质流动换热的重要基础参数且表征着其在稳态导热过程的导热能力,针对我国煤炭多样品种的煤质对水煤浆导热系数的影响研究具有现实意义。结合水煤浆样品制备,利用瞬态热线法测定不同煤质的导热系数,通过红外光谱、元素分析、XRD,研究煤质对水煤浆导热系数的影响,探究其灰分及石墨化程度对水煤浆导热系数的定量化关系。结果表明:在相同实验条件下煤浆导热系数与煤颗粒导热系数比值在1.2左右。煤质对煤的导热系数有显著影响,其中灰分和碳的石墨化程度是关键指标,灰分越高的煤种所制备的煤浆导热性能越高;原料表征石墨化程度的特征峰越强,石墨化程度越高,浆体导热性能越强。 展开更多
关键词 水煤浆 导热系数 煤质 石墨化程度 灰分 瞬态热线法 特征峰 定量化关系
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氢氧化钠法定量分析聚酯纤维与氨纶混纺织物
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作者 郭义侠 张春辉 +1 位作者 商大伟 吴丽敏 《针织工业》 北大核心 2025年第2期80-83,共4页
根据聚酯纤维和氨纶在氢氧化钠溶液中溶解性能的差异,采用氢氧化钠法对聚酯纤维与氨纶的混纺织物进行纤维含量定量分析。通过改变氢氧化钠浓度、试验温度和试验时间,优化最佳溶解工艺,并与传统手工分解法对比,验证氢氧化钠法定量分析聚... 根据聚酯纤维和氨纶在氢氧化钠溶液中溶解性能的差异,采用氢氧化钠法对聚酯纤维与氨纶的混纺织物进行纤维含量定量分析。通过改变氢氧化钠浓度、试验温度和试验时间,优化最佳溶解工艺,并与传统手工分解法对比,验证氢氧化钠法定量分析聚酯纤维与氨纶混纺织物的可行性。结果表明,氢氧化钠溶液对聚酯纤维与氨纶混纺织物定量分析最佳条件为:50%氢氧化钠溶液,浴比1∶100,90℃水浴振荡15 min后取出,在筛网上冲洗并手动揉搓,重复上述步骤,聚酯纤维可在外力作用下完全与氨纶纤维分离并通过筛网的孔洞被冲洗掉,只剩下氨纶纤维;且最终得出的修正后的氨纶含量与手工分解法无明显差异。 展开更多
关键词 氢氧化钠法 聚酯纤维与氨纶混纺织物 定量分析 手工分解法
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基于内标法的表面增强拉曼光谱在定量分析中的应用
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作者 毕英娜 刘定斌 《高等学校化学学报》 北大核心 2025年第2期1-13,共13页
表面增强拉曼光谱(SERS)是一种已被广泛应用于疾病诊断、药物筛选及生物分析等领域的光谱检测方法,它不仅可以提供丰富的化学指纹信息,而且具有灵敏度高、抗光漂白和光降解能力强等优点.然而,由于SERS增强基底的结构均一性差和化学分子... 表面增强拉曼光谱(SERS)是一种已被广泛应用于疾病诊断、药物筛选及生物分析等领域的光谱检测方法,它不仅可以提供丰富的化学指纹信息,而且具有灵敏度高、抗光漂白和光降解能力强等优点.然而,由于SERS增强基底的结构均一性差和化学分子吸附数量的不确定性,导致检测结果重现性差,其定量分析面临诸多挑战.通过引入内标信号可以消除或减少外部干扰因素,从而实现SERS的准确定量分析.本文首先阐述了内标法的机理,然后介绍了内标法的主要类型,接着举例说明了内标型SERS探针在环境分析、食品药品分析以及生物分析等领域的应用,最后展望了内标型SERS面临的挑战及未来发展方向. 展开更多
关键词 表面增强拉曼光谱 定量分析 内标法
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基于GB/T 24067-2024的产品碳足迹量化方法与案例分析
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作者 温志英 索彦彦 +5 位作者 张强 李许 潘晓远 宋保靓 杨杰 陈新 《中国标准化》 2025年第3期179-183,共5页
随着全球气候变化议题日益凸显,产品碳足迹的量化评估已成为衡量企业环境责任及驱动绿色转型的关键工具。近期,中国发布的GB/T 24067—2024《温室气体产品碳足迹量化要求与指南》国家标准,为企业界构建了一个科学且系统的碳足迹量化框... 随着全球气候变化议题日益凸显,产品碳足迹的量化评估已成为衡量企业环境责任及驱动绿色转型的关键工具。近期,中国发布的GB/T 24067—2024《温室气体产品碳足迹量化要求与指南》国家标准,为企业界构建了一个科学且系统的碳足迹量化框架。本文依据该最新标准,深入探讨了产品碳足迹量化的核心方法论,并通过实例分析,直观展示了其在实际操作中的实用性和可行性。研究揭示,GB/T 24067—2024标准不仅为企业铺设了一条明确、全面的碳足迹量化道路,还助力企业发掘减排潜力,促进产品设计与供应链管理的优化升级,加速向绿色低碳经济迈进。 展开更多
关键词 GB/T 24067—2024 产品碳足迹 量化方法 案例分析 绿色低碳发展
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