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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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Left-Handedness with Three Zero-Absorption Windows Tuned by the Incoherent Pumping Field and Inter-Dot Tunnelings in a GaAs/AlGaAs Triple Quantum Dots System
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作者 赵顺才 张双颖 +1 位作者 吴奇宣 贾靖 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第5期157-160,共4页
Left-handedness with three zero-absorption windows is achieved in a triple-quantum-dot system. With the typ- ical parameters of a GaAs/AlGaAs heterostructure, the simultaneous negative relative electric permittivity a... Left-handedness with three zero-absorption windows is achieved in a triple-quantum-dot system. With the typ- ical parameters of a GaAs/AlGaAs heterostructure, the simultaneous negative relative electric permittivity and magnetic permeability are obtained by the adjustable incoherent pumping field and two inter-dot tunnelings. Furthermore, three zero-absorption windows in the left-handedness frequency bands are observed. The left- handedness with zero-absorption in the solid state heterostrueture may solve the challenges not only in the left-handed materials achieved by the photonic resonant scheme but also in the application of negative refractive materials with a large amount of absorption. 展开更多
关键词 In Left-Handedness with Three zero-absorption Windows Tuned by the Incoherent Pumping Field and Inter-Dot Tunnelings in a GaAs/AlGaAs Triple Quantum Dots System
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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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A promising leap in early screening for chronic kidney disease:The smartphone-integrated handheld automated biochemical analyzer
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作者 Ming Chen 《Journal of Pharmaceutical Analysis》 2025年第9期1942-1942,共1页
In the face of the escalating global prevalence of chronic kidney disease(CKD),early diagnosis and effective management have become crucial imperatives[1].The article“Development of a smartphone-integrated handheld a... In the face of the escalating global prevalence of chronic kidney disease(CKD),early diagnosis and effective management have become crucial imperatives[1].The article“Development of a smartphone-integrated handheld automated biochemical analyzer for point-of-care testing of urinary albumin”by Wu et al.[2]presents a novel smartphone-integrated handheld automated biochemical analyzer(sHABA),which offers new possibilities for the early diagnosis and management of CKD,holding great significance for improving patients’health. 展开更多
关键词 biochemical analyzer point care testing urinary albumin smartphone integrated handheld automated biochemical analyzer chronic kidney disease improving pati chronic kidney disease ckd early early screening
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Development of a smartphone-integrated handheld automated biochemical analyzer for point-of-care testing of urinary albumin
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作者 Ze Wu Peng Zhang +7 位作者 Wei Xiao Qian Chen Wangrun Lin Peipei Chen Kangwei Chen Qiangqiang Fu Zhijian Wang Lei Zheng 《Journal of Pharmaceutical Analysis》 2025年第3期577-584,共8页
The level of urinary albumin is a critical indicator for the early diagnosis and management of chronic kidney disease(CKD).However,existing methods for detecting albumin are not conducive to point-of-care testing due ... The level of urinary albumin is a critical indicator for the early diagnosis and management of chronic kidney disease(CKD).However,existing methods for detecting albumin are not conducive to point-of-care testing due to the complexity of reagent addition and incubation processes.This study presents a smartphone-integrated handheld automated biochemical analyzer(sHABA)designed for point-of-care testing of urinary albumin.The sHABA features a pre-loaded,disposable reagent cassette with reagents for the albumin assay arranged in the order of their addition within a hose.The smartphone-integrated analyzer can drive the reagents following a preset program,to enable automatic sequential addition.The sHABA has a detection limit for albumin of 5.9 mg/L and a linear detection range from 7 to 450 mg/L.The consistency of albumin level detection in 931 urine samples using sHABA with clinical tests indicates good sensitivity(95.78%)and specificity(90.16%).This research advances the field by providing an automated detection method for albumin in a portable device,allowing even untrained individuals to monitor CKD in real time at the patient's bedside.In the context of promoting tiered diagnosis and treatment,the sHABA has the potential to become an essential tool for the early diagnosis and comprehensive management of CKD and other chronic conditions. 展开更多
关键词 Chronic kidney disease ALBUMIN SMARTPHONE Biochemical analyzer Point-of-care testing
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Comparison of biomechanical indices measured by ocular response analyzer between children and elderly:a systematic review
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作者 Hassan Hashemi Fereshteh Shokrollahzadeh +2 位作者 Hadi Ostadimoghaddam Abbasali Yekta Mehdi Khabazkhoob 《International Journal of Ophthalmology(English edition)》 2025年第1期154-159,共6页
Biomechanical study of the visual system by ocular response analyzer investigates the inter-structural biological relationships,mechanics,and function of the visual system.This review aimed to investigate the changes ... Biomechanical study of the visual system by ocular response analyzer investigates the inter-structural biological relationships,mechanics,and function of the visual system.This review aimed to investigate the changes in corneal biomechanical parameters with age and sex.The articles published in PubMed between 2000 and 2021 were investigated and critiqued,and valid scientific evidence was collected,reviewed and concluded according to the inclusion and exclusion criteria.Most studies showed that corneal biomechanical changes occur infrequently in children up to the age of 20y,and with increasing age and wider age range,there was a significant decrease in corneal biomechanical indices,especially corneal hysteresis.In children and adults,most studies have shown that these biomechanical indicators,especially corneal resistance factor,were higher in females.Although hormonal changes may contribute to this finding,the role of axial length and other biometric indicators should not be ignored.The axial length,the intraocular pressure,and the corneal thickness are other factors associated with biomechanical parameters that should be taken into account in clinical diagnosis and management especially for patients undergoing refractive surgery as well as keratoconus patients. 展开更多
关键词 ocular response analyzer corneal biomechanics visual function CHILDREN ELDERLY
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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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血细胞分析仪WDF和WNB散点图在血小板数量检测质量管理中的应用
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作者 张宁 何晓璇 孟欣 《现代检验医学杂志》 2026年第2期187-191,共5页
目的探讨并验证白细胞WDF通道散点图(WDF)和白细胞WNB通道散点图(WNB)在监测血液微小凝集、大血小板及血小板聚集中的价值。方法收集2023年4~12月西安交通大学第一附属医院EDTA-K2血液样本1788例,Mindray BC-6800 Plus全自动血细胞分析... 目的探讨并验证白细胞WDF通道散点图(WDF)和白细胞WNB通道散点图(WNB)在监测血液微小凝集、大血小板及血小板聚集中的价值。方法收集2023年4~12月西安交通大学第一附属医院EDTA-K2血液样本1788例,Mindray BC-6800 Plus全自动血细胞分析仪触发血小板聚集报警,或血小板直方图异常,或WDF、WNB散点图Ghost区域异常时,使用MC-80全自动血细胞形态学分析仪判断不同异常报警与血液微小凝集、血小板聚集及大血小板的关系。结果173例WDF散点图Ghost区域异常样本,血小板数量减低,与重新采集血液前比较,重新采集血液后血小板数量明显增高,差异具有统计学意义(Z=-10.009,P<0.05)。1252例WNB散点图Ghost区域异常的样本,MC-80全自动血细胞形态学分析系统镜检提示大血小板1035例(占比82.67%)、血小板聚集217例(占比17.33%),平均血小板体积(MPV)、大血小板比率(P-LCR)、血小板分布宽度标准差(PDW-SD)血小板聚集样本明显低于大血小板样本,差异具有统计学意义(t=9.785、8.682、8.344,均P<0.05)。血小板压积(PCT)、大血小板数量(P-LCC)血小板聚集样本高于大血小板样本,差异无统计学意义(t=-1.490、-0.777,均P>0.05)。200例大血小板样本,电阻抗法血小板(PLT-I)计数为100(84,127)×10^(9)/L,光学血小板(PLT-O)计数为104(85,132)×10^(9)/L,PLT-O高于PLT-I计数,差异无统计学意义(Z=-0.280,P>0.05)。217例WNB散点图Ghost区域异常的血小板聚集样本,PLT-I计数为95(77,119)×10^(9)/L,PLT-O计数为110(89,146)×10^(9)/L,PLT-O高于PLT-I计数,差异具有统计学意义(Z=-2.987,P<0.05)。结论血细胞分析检测及报告审核过程应结合血细胞计数、WDF散点图、WNB散点图、血小板直方图等信息,合理制定血小板复检规则及流程,必要时结合形态学分析结果综合判断,以保证血细胞分析检验结果准确可靠。 展开更多
关键词 散点图 血细胞分析仪 血小板 复检流程
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基于“场景词袋”方法的历史街区访客行为数据多模态分析与人本更新应用
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作者 肖竞 付梦姣 +2 位作者 陶建宇 曹珂 钱笑 《西部人居环境学刊》 北大核心 2026年第1期149-155,共7页
针对存量时期城乡遗产保护由防御保控“物本”逻辑向文化传承“人本”逻辑转变的现实背景,以及历史街区访客行为研究分析模态系统性不足、数据模态可公度性不足的技术瓶颈,文章基于人本更新视角,结合“场景理论”与“词袋模型”建构了... 针对存量时期城乡遗产保护由防御保控“物本”逻辑向文化传承“人本”逻辑转变的现实背景,以及历史街区访客行为研究分析模态系统性不足、数据模态可公度性不足的技术瓶颈,文章基于人本更新视角,结合“场景理论”与“词袋模型”建构了历史街区访客行为数据多模态分析方法,用以解析历史街区空间—访客行为互动机理。该方法建立了以数据模态为输入模态、分析模态为输出模态的多源数据系统归口与开放式研究框架,以及基于人群类别、行为类别、时间周期和空间属性四维场景要素的“词袋标签”和“单词语义”模型。基于样本研究,揭示出历史街区访客行为趋同从众、赶逐匆促、外骛表浅、交互性弱的现实问题和重商轻文、平悠假促、昼游夜览的时空分异规律,以及不同性别、来源地、年龄访客行为在独立性、目的性、活力度方面的分异表现。据此提出靶点空间干预、流态场景组构、差异场景营造的人本更新策略,以期丰富、拓展既有历史街区访客行为理论,推动历史街区文化传承与人本更新实践范式创新。 展开更多
关键词 历史街区 访客行为 场景词袋 人本更新 数据模态 分析模态
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面向卓越工程师人才培养的大学物理实验教学改革与实践
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作者 胡雪兰 张艳峰 王亚如 《高教学刊》 2026年第8期139-142,共4页
大学物理实验在提高学生科学素质、培养学生科学实验能力、知识迁移应用能力、分析解决问题能力中有重要作用。借鉴法国精英工程师预科物理实验教学模式,该文从教学目标设定、实验内容的设置和考核方法的创新三个方面阐述在特色物理实... 大学物理实验在提高学生科学素质、培养学生科学实验能力、知识迁移应用能力、分析解决问题能力中有重要作用。借鉴法国精英工程师预科物理实验教学模式,该文从教学目标设定、实验内容的设置和考核方法的创新三个方面阐述在特色物理实验中进行的改革与实践效果。实验过程中注重学生对于基础知识的掌握、对于具体问题的分析解决、对于新的知识快速吸收应用及团队协作能力的培养,为卓越工程师人才培养提供有效支撑,可以为其他实验类课程提供一定的参考。 展开更多
关键词 大学物理实验 卓越工程师培养 分析解决实际问题的能力 评价方式 教学改革
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语音分析软件Speech Analyzer和Praat在上海市区方言鼻化韵单一化演变研究中的应用 被引量:6
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作者 顾钦 《计算机应用与软件》 CSCD 北大核心 2006年第12期81-82,108,共3页
目前我国方言语音演变研究中音位的确定主要以传统意义上的研究方法为多,音位归纳主要凭个人经验。若记音人本身记音能力有限,可能造成记录结果与方言实际读音存在偏差。因此,如果在传统记音方法的基础上,辅以语音分析软件,将使方言语... 目前我国方言语音演变研究中音位的确定主要以传统意义上的研究方法为多,音位归纳主要凭个人经验。若记音人本身记音能力有限,可能造成记录结果与方言实际读音存在偏差。因此,如果在传统记音方法的基础上,辅以语音分析软件,将使方言语音研究更为精密、客观。以Speech Analyzer和Praat语音分析软件为例,結合上海市区方言鼻化韵单一化,即鼻化韵中前a后ɑ的对立完全消失,发成中A这一语音演变现象,以Speech Analyzer确定鼻化元音位置,以Praat做共振峰分析,为这一语音演变现象的确定提供证据。 展开更多
关键词 语音分析软件 SPEECH analyzER Praat上海市区方言 鼻化韵单一化
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Rapid Determination of Lysine Content in Maize Kernel by Amino-acid Analyzer 被引量:1
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作者 齐建双 铁双贵 +3 位作者 韩小花 岳润清 燕树锋 卢彩霞 《Agricultural Science & Technology》 CAS 2015年第7期1340-1342,1397,共4页
In this study, nine high-lysine maize kernels and two kernels of common maize hybrid were used as experiment materials, and quantitative determination of lysine contents in high-lysine maize kernels and common maize k... In this study, nine high-lysine maize kernels and two kernels of common maize hybrid were used as experiment materials, and quantitative determination of lysine contents in high-lysine maize kernels and common maize kernels was carried out using Hitachi L-8900 Automatic Amino-acid Analyzer, to know the effect of the Analyzer in distinguishing the lysine contents between common maize kernels and high-lysine maize kernels. The results showed that the lysine contents of high-lysine maize kernels were among 0.34%-0.42%, while of common maize kernels were a- mong 0.24%-0.25%, and the difference was significant. Compared with other tradi- tional methods, this method is rapid, simple, sensitive, highly reproductive and needs fewer maize kernels, thus it is applicable in maize breeding. 展开更多
关键词 Amino-acid analyzer High lysine MAIZE
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使用Thomson Data Analyzer进行专利分析的几点研究 被引量:4
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作者 顾震宇 卞志昕 《竞争情报》 2007年第2期10-12,共3页
专利分析软件作为专利数据挖掘的工具,可以用作行业趋势分析、技术追踪、竞争对手监视等,目前正得到企业越来越广泛的重视。Thomson DataAnalyzer作为一款基于Derwent世界专利数据库基础上开发的专利分析软件,具有其独特的优势。本文在... 专利分析软件作为专利数据挖掘的工具,可以用作行业趋势分析、技术追踪、竞争对手监视等,目前正得到企业越来越广泛的重视。Thomson DataAnalyzer作为一款基于Derwent世界专利数据库基础上开发的专利分析软件,具有其独特的优势。本文在对TDA软件介绍的基础上,对使用中如何进行数据整理,以及如何进行技术领域分析进行了研究。 展开更多
关键词 专利分析软件 数据整理 技术领域分析 THOMSON DATA analyzER TDA
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Thomson Data Analyzer在机构专利情报分析中的应用研究 被引量:28
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作者 冯浩然 方曙 《情报科学》 CSSCI 北大核心 2008年第12期1833-1836,1843,共5页
使用Thomson Data Analyzer TDA(TDA)软件对1986-2005年期间在Derwent InnovationIndex DII(DII)中收录的德国马普学会(MPG)、美国国立卫生研究院(NIH)、美国斯坦福大学(Stanford)、美国康奈尔大学(Cornell)、美国威斯康辛州立大学(Wisc... 使用Thomson Data Analyzer TDA(TDA)软件对1986-2005年期间在Derwent InnovationIndex DII(DII)中收录的德国马普学会(MPG)、美国国立卫生研究院(NIH)、美国斯坦福大学(Stanford)、美国康奈尔大学(Cornell)、美国威斯康辛州立大学(Wisconsin)、日本东京大学(Tokyo)六家机构的专利数据,从专利数量、发明技术领域、机构对外合作情况、专利家族国家分布和技术领域相似度5个方面进行了比较分析。 展开更多
关键词 专利分析 技术领域 合作情况 专利家族
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基于质构仪和电子鼻技术对豆腐乳发酵过程中品质变化的研究
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作者 路翔程 赵红梅 +5 位作者 杨艳君 马晓丽 李祥 李卓渊 薛莎莎 罗爱国 《中国调味品》 北大核心 2026年第2期27-32,共6页
为了探究豆腐乳发酵过程中品质的变化,采用质构仪、电子鼻技术和常规分析方法检测其硬度、咀嚼性、风味和理化指标。结果表明,在发酵过程中,豆腐乳的硬度和咀嚼性分别从8.53 N和18.96 mJ下降到4.02 N和6.16 mJ,硬度降低使豆腐乳的咀嚼... 为了探究豆腐乳发酵过程中品质的变化,采用质构仪、电子鼻技术和常规分析方法检测其硬度、咀嚼性、风味和理化指标。结果表明,在发酵过程中,豆腐乳的硬度和咀嚼性分别从8.53 N和18.96 mJ下降到4.02 N和6.16 mJ,硬度降低使豆腐乳的咀嚼性变得更适宜;差异香气物质主要为硫化物、烷烃类、醇类和醛类;感官评分随着发酵时间的增加而升高;水分含量、食盐含量分别从60.84%和6.71 g/100 g下降到60.34%和6.53 g/100 g,总酸含量、水溶性蛋白质含量、氨基酸态氮含量分别从0.18,2.966,0.15 g/100 g上升到0.71,3.635,0.65 g/100 g;食盐的添加引起水分流失和微生物代谢活动,间接影响豆腐乳的硬度、咀嚼性和食盐含量,是影响豆腐乳发酵品质的关键因素。该研究为豆腐乳的发酵工艺优化、风味调整和产品创新提供了理论支持。 展开更多
关键词 豆腐乳 质构仪 电子鼻 理化指标
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有机碳/元素碳热光分析方法的数据质控和优化
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作者 李楠 马银红 +2 位作者 王健 王静 杨文 《中国环境监测》 北大核心 2026年第1期115-125,共11页
热光分析方法是国内外普遍使用的分析大气颗粒物中碳组分的方法。以当前主流DRI 2001A型有机碳(Organic Carbon,OC)/元素碳(Elemental Carbon,EC)分析仪为例,对热光分析法使用过程中的质量控制要求进行了确认和优化,主要包括滤膜前处理... 热光分析方法是国内外普遍使用的分析大气颗粒物中碳组分的方法。以当前主流DRI 2001A型有机碳(Organic Carbon,OC)/元素碳(Elemental Carbon,EC)分析仪为例,对热光分析法使用过程中的质量控制要求进行了确认和优化,主要包括滤膜前处理、温度校准、标准物质选取、三峰检测和碳酸盐碳(Carbonate Carbon,CC)去除5个方面,并提出最优质控要求。得到的结论主要包括:(1)用于碳组分分析的空白石英纤维滤膜在马弗炉中以550℃烘烤3 h,即可使总碳(Total Carbon,TC)测量值低于0.5μg/cm^(2)。(2)在启动新仪器前以及更换热电偶后,应对仪器进行温度校准。滤膜实际温度与仪器设置温度的差值在15℃以下时,可使每个温度阶段的碳组分浓度的相对偏差低于30%。(3)邻苯二甲酸氢钾(KHP)和蔗糖标准溶液均可用于标定校准,二者TC测量值与标准值的相对误差范围分别为-3.0%~3.1%和-4.8%~3.0%,校准曲线斜率的相对偏差为2.9%。(4)当CH4峰面积的差值高于5000 mV·s或相对偏差超过9%时,三峰检测结果的相对标准偏差(Relative Standard Deviation,RSD)值在5%以内逐渐增大,说明还原管活性在逐渐减弱。当三峰检测结果的RSD超过5%时,应检查气瓶压力、仪器气密性、氧化管或还原管活性等,并重新绘制校准曲线。(5)特定样品应添加0.4 mol/L HCl去除CC,否则会严重干扰OC和EC的检测浓度。加酸量可通过Ca^(2+)浓度确定。当Ca^(2+)浓度在30 mg/L以上时,加20μL即可完全去除CC;当Ca^(2+)浓度在10 mg/L以下时,不建议进行加酸处理;当Ca^(2+)浓度在10~30 mg/L之间时,需通过预实验确定加酸量。通过开展热光分析法质控要求确认和优化,可更好地对仪器测量数据进行质量控制,提高分析结果的可靠性和可比性。 展开更多
关键词 有机碳/元素碳分析仪 温度校准 三峰检测 碳酸盐碳 优化
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基于智能感官的襄阳牛肉面品质评价方法
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作者 沈慧婷 肖飞 +5 位作者 丁知画 方诗怡 唐梓豪 汤尚文 刘传菊 豁银强 《保鲜与加工》 北大核心 2026年第1期116-128,共13页
为建立一种客观基于智能感官分析仪器(质构仪、电子舌和电子鼻)评价襄阳牛肉面品质的方法,以襄阳牛肉面为研究对象,分别从质地(A1)、滋味(A2)和气味(A3)进行检测,对采集的数据进行标准化处理后,利用偏最小二乘法判别分析法(Partial leas... 为建立一种客观基于智能感官分析仪器(质构仪、电子舌和电子鼻)评价襄阳牛肉面品质的方法,以襄阳牛肉面为研究对象,分别从质地(A1)、滋味(A2)和气味(A3)进行检测,对采集的数据进行标准化处理后,利用偏最小二乘法判别分析法(Partial least squares discriminant analysis,PLS-DA)筛选出关键品质指标,并结合层次分析法(Analytic hierarchy process,AHP)和熵权法(Entropy weight method,EWM)确定各指标的复合权重,构建智能评分模型。结果表明,经PLS-DA法共筛选出坚实度、弹性、酸味、鲜味、W1S、W1W和W2S七项关键评分指标,其复合权重分别为40.96%、19.04%、17.68%、6.32%、4.20%、8.76%和3.04%。由此建立的襄阳牛肉面智能评分模型为:F_(智能)=0.4096X_(1)+0.1904X_(2)+0.1768X_(3)+0.0632X_(4)+0.0420X_(5)+0.0876X_(6)+0.0304X_(7),其中X_(1)~X_(7)为各指标的标准化值。智能评分与人工评分显著相关,Pearson相关系数为0.93,R^(2)=0.86,表明所建立的模型预测性能良好。综上,基于智能感官仪器构建的襄阳牛肉面的评分模型客观、准确、操作简便,能够替代人工感官评价,适用于襄阳牛肉面的品质评估,并为同类地方特色面制食品的质量控制提供了理论支持和方法参考。 展开更多
关键词 襄阳牛肉面 智能感官 品质评价 质构仪 电子舌 电子鼻
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PLC Analyzer在多工位快速液压机中的应用
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作者 施宝酉 杜立峰 李利清 《锻压装备与制造技术》 2016年第2期37-39,共3页
介绍快速液压机工作原理以及PLC Analyzer软件的使用,通过PLC Analyzer软件在多工位快速压机中的使用,实现了对各种信号的数据采集与存储功能,便于分析、解决调试过程中出现的不定期的异常故障,优化了压机调试参数。借助该软件可快速、... 介绍快速液压机工作原理以及PLC Analyzer软件的使用,通过PLC Analyzer软件在多工位快速压机中的使用,实现了对各种信号的数据采集与存储功能,便于分析、解决调试过程中出现的不定期的异常故障,优化了压机调试参数。借助该软件可快速、准确地发现设备故障点,弥补传统PLC无法对瞬时故障信号记录以及判断的缺陷。 展开更多
关键词 多工位快速液压机 数据采集 PLC analyzER 故障诊断 节拍优化
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低成本高集成多道脉冲幅度分析器设计与实现
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作者 彭瑞吉 蒋镖 +3 位作者 邓豪 肖鸿飞 唐晟睿 张庆贤 《核电子学与探测技术》 北大核心 2026年第3期324-331,共8页
数字多道脉冲幅度分析器目前已成为能谱测量的主流技术,其中采用“高速模数转换器(Analog-to-Digital Converter,ADC)+现场可编辑门阵列(Field Programmable Gate Array,FPGA)+先进精简指令集机器(Advanced RISC Machine,ARM)芯片”架... 数字多道脉冲幅度分析器目前已成为能谱测量的主流技术,其中采用“高速模数转换器(Analog-to-Digital Converter,ADC)+现场可编辑门阵列(Field Programmable Gate Array,FPGA)+先进精简指令集机器(Advanced RISC Machine,ARM)芯片”架构的产品,虽数字化程度高,但体积相对较大、成本和功耗高。模拟多道脉冲幅度分析器具有成本低、功耗低、结构简单的特点。本文针对低成本、小体积和低功耗的应用需求,研制了一款低成本高集成小体积多道脉冲幅度分析器,采用STM32H750芯片为核心器件,通过其内置ADC进行脉冲幅度提取。设计和优化了过零触发电路及脉冲幅度提取流程,减少脉冲处理死时间,提高脉冲通过率。通过对多道脉冲幅度分析器测试,基线噪声约为1.3 mV,能量线性度为0.9995,能量分辨率为4.1%@662 keV(CeBr_(3)),脉冲处理死时间约为13μs,适用于低计数率低成本的应用场景。 展开更多
关键词 小体积 多道脉冲幅度分析器 峰值保持 过零触发
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因子混合模型稳健贝叶斯分析
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作者 吕天予 夏业茂 《应用数学》 北大核心 2026年第1期161-172,共12页
为了降低异常点或极值数据影响,本文对因子混合模型建立了稳健分析.在参数统计框架内,基于正态尺度混合分布,对数据点赋以适当的权重来降低异常点的影响.我们还对因子负荷采用稀疏化技术来提高模型的泛化能力,并对因子个数和混合分量个... 为了降低异常点或极值数据影响,本文对因子混合模型建立了稳健分析.在参数统计框架内,基于正态尺度混合分布,对数据点赋以适当的权重来降低异常点的影响.我们还对因子负荷采用稀疏化技术来提高模型的泛化能力,并对因子个数和混合分量个数展开选择.随机模拟和对橄榄油数据分析展示了方法的有效性和实用性. 展开更多
关键词 混合因子模型 正态尺度混合 全局-局部收缩 MCMC抽样
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