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全自动间断化学分析法快速测定水中硅酸根
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作者 郭一楷 蒙英异 +4 位作者 阴珂珂 张倩 刘媛媛 王迪 王凌青 《中国无机分析化学》 北大核心 2025年第4期515-522,共8页
硅酸根离子(SiO_(3)^(2-))在水体中的浓度变化直接反映了水体污染程度及其对生态系统和健康的潜在影响。传统硅酸盐测定方法难以满足快速、简便、经济的现场检测需求。随着仪器智能自动化技术的快速发展,全自动间断化学分析技术(Autoch... 硅酸根离子(SiO_(3)^(2-))在水体中的浓度变化直接反映了水体污染程度及其对生态系统和健康的潜在影响。传统硅酸盐测定方法难以满足快速、简便、经济的现场检测需求。随着仪器智能自动化技术的快速发展,全自动间断化学分析技术(Autochem)结合成熟分析原理,实现对多种目标物质的高通量、高精确度的快速测定。采用Autochem测定水体中的硅酸根离子浓度,系统评估方法的检测下限、精密度及加标回收率,并与传统光谱法(紫外-可见分光光度法,UV-Vis)和先进的发射光谱法(电感耦合等离子体发射光谱法,ICP-OES)进行比较。结果表明,Autochem测定浓度范围较宽,覆盖0~30.0 mg/L,在低浓度和高浓度条件下的检测下限分别为0.047 mg/L和0.089 mg/L,加标回收率为95.0%~105%。同时,Autochem以其先进的自动化技术和成熟的分析原理,实现高效、精确的环境样品测定,适合于大量水样的快速分析。使用Autochem测定水中硅酸根含量有助于提高常规水质监测的工作效率,为大规模水环境调查和实时监控提供有力支持。 展开更多
关键词 硅酸根 地表水 紫外可见分光光度法 全自动间断化学分析法
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汉中地产茶叶中茶多酚含量的测定及其抗氧化活性研究
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作者 潘雪 杨博 屈撑囤 《广州化工》 2025年第3期79-82,共4页
多酚类物质具有生理活性,对心血管疾病有一定的预防作用,同时其含量也是评价茶叶的优劣的重要指标。但是,目前针对地产茶叶中茶多酚含量的研究,汉中地区尚有不足。为了弥补汉中地区地产茶叶研究空缺,提升汉中茶文化影响力和知名度,设计... 多酚类物质具有生理活性,对心血管疾病有一定的预防作用,同时其含量也是评价茶叶的优劣的重要指标。但是,目前针对地产茶叶中茶多酚含量的研究,汉中地区尚有不足。为了弥补汉中地区地产茶叶研究空缺,提升汉中茶文化影响力和知名度,设计实验采用分光光度计法,对汉中地区地产茶叶的茶多酚含量和抗氧化活性进行了研究。在明确采用超声波提取法作为最佳提取条件的基础上,针对从茶叶提取的茶多酚,进行了浓度和抗氧化活性的相关研究。结果显示,超声波提取茶多酚过程中,溶剂为75%的乙醇时提取效果最好,经酒石酸亚铁标准曲线法计算得出汉中地产茶叶茶多酚含量为3.28%±0.06%,高于其他地区茶饮平均水平;甲基橙褪色吸光光度法测定抗氧化活性结果显示,其最大值为97.9%,可以消除人体过多的·OH,在人体内可发挥更好的生理作用。此次研究的结果对综合评价汉中地产茶叶品质,提高汉中地区茶饮知名度具有一定参考价值。 展开更多
关键词 茶多酚 抗氧化性 乙醇 分光光度计
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Assessment of Arsenic in Rice and Cooked Rice in Meherpur, Bangladesh: Associated Health Risks Implications
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作者 Tasnim Saekh Antik Sadia Islam Mou 《Journal of Geoscience and Environment Protection》 2025年第1期457-474,共18页
Arsenic is a toxic element. Chronic exposure to arsenic can pose a variety of health problems including cancers, lung disease, skin lesions, diabetes, gangrene, reproductive disorders, hypertension, and heart disease.... Arsenic is a toxic element. Chronic exposure to arsenic can pose a variety of health problems including cancers, lung disease, skin lesions, diabetes, gangrene, reproductive disorders, hypertension, and heart disease. Globally the concern of arsenic is growing day by day. Addressing this concern, the study aimed to assess the arsenic level in raw rice grain and rice cooked with tubewell water and rainwater. The study was conducted at the Sholotaka Union of Gangni Upazila in Meherpur District of Khulna Division, Bangladesh in 2023. For this purpose, seven raw samples including rice grain, rainwater and tubewell water samples and six cooked rice samples were analyzed. Rice and water samples were digested using the USEPA method-3050B in Arsenic Center Jashore, under Asia Arsenic Network, Japan. The arsenic level in the samples was tested using the HG-AAS method using a Shimadzu model AA7000 (Japan) Atomic Absorption Spectrophotometer. The study’s findings revealed that arsenic concentration in rainwater samples consistently displays 0 mg/l indicating the absence of arsenic in this sample. Three (03) tube well water samples and three (03) raw rice grain samples showed a significant variation in arsenic concentration. The mean value of tubewell water samples T1, T2, and T3 was found 0.53 ± 0.003 mg/l, 0.31 ± 0.003 mg/l, and 0.65 ± 0.002 mg/l, respectively. Whereas raw rice grain samples RG1 showed a mean of 0.607 ± 0.007 mg/kg, RG2 at 0.458 ± 0.008 mg/kg, and RG3 at 0.7145 ± 0.001 mg/kg. The study found that rice cooked with tubewell water contained a higher arsenic concentration than rice cooked with rainwater. The most prominent finding of this study was that cooked rice using rainwater had a lower amount of arsenic than the raw rice grain. So, it is clearly said that using rainwater can minimize the amount of arsenic. Furthermore, the study indicates that the health risks associated with arsenic exposure have increased. Estimated daily intake (EDI) values for cooked rice samples ranged from 3.07 to 5.47 μg/kg body weight/day, exceeding safe limits. Target Hazard Quotient (THQ) values varied from 10.2 to 18.2, indicating significant potential for non-carcinogenic health effects. Lifetime Cancer Risk (LCR) values ranged from 0.461% to 0.821% exceeding the U.S. Environmental Protection Agency’s acceptable risk threshold of 0.01%, which reflects a heightened cancer risk. The study suggests that people in the study area should use rainwater instead of tubewell water for their cooking purposes. Furthermore, rainwater harvesting should be prioritized in this area to address arsenic issues. 展开更多
关键词 ARSENIC Rice grain Atomic Absorption spectrophotometer Cooked Rice Health Risks
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影响煤炭中砷含量测定因素的研究
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作者 赵积坤 《化工管理》 2025年第4期62-64,共3页
煤炭中砷含量的测定方法按照GB/T 3058—2019 《煤中砷的测定方法》中的砷钼蓝分光光度法为仲裁方法。文章主要研究不同因素对砷钼蓝分光光度法的影响关系,主要有煤炭处理燃烧时间、不同的测定波长、水浴加热时间、无砷锌与样品反应时... 煤炭中砷含量的测定方法按照GB/T 3058—2019 《煤中砷的测定方法》中的砷钼蓝分光光度法为仲裁方法。文章主要研究不同因素对砷钼蓝分光光度法的影响关系,主要有煤炭处理燃烧时间、不同的测定波长、水浴加热时间、无砷锌与样品反应时间。通过对不同条件下砷的测定,分析得出影响砷含量测定的影响关系。 展开更多
关键词 煤中砷 测定 砷钼蓝分光光度法
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高浓度六价铬溶液标准物质制备
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作者 王琳琳 刘媛媛 +3 位作者 管其红 黄清波 朱建强 郭波 《化学分析计量》 2025年第1期1-5,共5页
研制高浓度六价铬溶液标准物质。以重铬酸钾纯度标准物质为原料,以1%硝酸溶液为溶剂,采用重量-容量法制备质量浓度为100μg/mL的水中六价铬溶液标准物质,利用紫外可见分光光度计直接测定水中高浓度六价铬的方法对标准物质进行均匀性、... 研制高浓度六价铬溶液标准物质。以重铬酸钾纯度标准物质为原料,以1%硝酸溶液为溶剂,采用重量-容量法制备质量浓度为100μg/mL的水中六价铬溶液标准物质,利用紫外可见分光光度计直接测定水中高浓度六价铬的方法对标准物质进行均匀性、稳定性检验及量值核验。F-检验和回归曲线结果表明,研制的标准物质具有良好的均匀性和稳定性;比对验证结果表明,其准确度与国家二级标准物质一致。该标准物质可为环境检测等领域六价铬检测数据的准确、可靠和互认提供保障。 展开更多
关键词 高浓度六价铬 紫外可见分光光度法 标准物质 不确定度
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紫外可见分光光度计在食品检测中的应用探讨
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作者 刘君萍 《食品安全导刊》 2025年第4期129-131,135,共4页
紫外可见分光光度计凭借操作简便、分析速度快、灵敏度高、重复性好等特点,在食品检测领域发挥着重要作用,为食品质量安全控制提供了可靠的技术支持。本文简要介绍紫外可见分光光度计的工作原理和应用优势,重点阐述其在食品添加剂定性... 紫外可见分光光度计凭借操作简便、分析速度快、灵敏度高、重复性好等特点,在食品检测领域发挥着重要作用,为食品质量安全控制提供了可靠的技术支持。本文简要介绍紫外可见分光光度计的工作原理和应用优势,重点阐述其在食品添加剂定性定量分析、营养成分测定、食品污染物检测以及食品真伪鉴别等方面的应用。 展开更多
关键词 紫外可见分光光度计 食品检测 添加剂 营养成分 污染物
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一种测定乳制品中蛋白酶活力的快速检测方法
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作者 冯美红 《中国乳业》 2025年第1期46-49,共4页
[目的]为控制蛋白酶引起的质量问题,需测定牛奶中蛋白酶活力。[方法]针对乳及乳制品领域蛋白酶活力检测没有国家标准方法,本文介绍一种用紫外分光光度计-福林法测定乳及乳制品中蛋白酶活力的快速检测方法。[结果]本研究采用的标准曲线... [目的]为控制蛋白酶引起的质量问题,需测定牛奶中蛋白酶活力。[方法]针对乳及乳制品领域蛋白酶活力检测没有国家标准方法,本文介绍一种用紫外分光光度计-福林法测定乳及乳制品中蛋白酶活力的快速检测方法。[结果]本研究采用的标准曲线范围呈线性关系,满足测试要求。由精密度和加标回收率试验结果可知,该方法加标回收率在正常范围内。[结论]紫外分光光度计-福林法能用于乳及乳制品中蛋白酶活力检测。 展开更多
关键词 乳制品 蛋白酶活力 苦味 紫外分光光度计-福林法
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水泥中水溶性铬(Ⅵ)的测定实验影响因素研究
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作者 贾月彩 马丽 +2 位作者 王丽英 李皓 朱跃华 《水泥技术》 2025年第1期75-80,共6页
研究了水泥中水溶性铬(Ⅵ)含量检测的实验原理,采用分光光度计测量显色剂与水溶性铬(Ⅵ)在酸性溶液中的络合反应物的吸光度,可以间接测量计算出水泥样品中水溶性铬(Ⅵ)的含量。采用不同水溶性铬(Ⅵ)含量的水泥标准样品和对照样品进行实... 研究了水泥中水溶性铬(Ⅵ)含量检测的实验原理,采用分光光度计测量显色剂与水溶性铬(Ⅵ)在酸性溶液中的络合反应物的吸光度,可以间接测量计算出水泥样品中水溶性铬(Ⅵ)的含量。采用不同水溶性铬(Ⅵ)含量的水泥标准样品和对照样品进行实验,研究了显色剂质量、实验溶液pH值、调酸时间、显色后静置时间和实验温度等对测定结果准确性的影响。结果显示,显色剂质量不同,测定结果准确性不同;实验溶液pH值偏大,会导致测量结果产生负误差,pH值偏小对测定结果影响不大;实验溶液调酸时间应控制在30s内,显色完成后实验溶液静置时间宜在15min以上、20min以内;一定区间内的实验温度对水溶性铬(Ⅵ)测定结果影响不大。 展开更多
关键词 水溶性铬(Ⅵ) 分光光度计 显色剂 络合反应 实验测量
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植物油精炼辅料中总砷、铅含量的检测方法
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作者 杨倩 杨亚 +4 位作者 孙玉萍 陈伟 黄国栋 胡金华 龚俊 《粮食加工》 2025年第1期91-95,共5页
建立一种统一且高效的检测方法,用于测定植物油精炼辅料(脱色土、磷酸、液碱)总砷、铅含量。通过硝酸消解脱色土,在石墨消解仪中于120℃加热60 min;磷酸、液碱用硝酸酸化,再用纯水稀释,原子荧光光度计测定总砷含量,原子吸收仪测定铅含... 建立一种统一且高效的检测方法,用于测定植物油精炼辅料(脱色土、磷酸、液碱)总砷、铅含量。通过硝酸消解脱色土,在石墨消解仪中于120℃加热60 min;磷酸、液碱用硝酸酸化,再用纯水稀释,原子荧光光度计测定总砷含量,原子吸收仪测定铅含量。结果表明,砷:脱色土、磷酸、液碱在方法检出限分别为0.197、0.017、0.040 mg/kg的基础上,其加标回收率分别为81.3%~90.2%、82.6%~98.3%、97.2%~99.7%,RSD(n=3)分别为4.78%~18.36%、1.61%~3.65%、1.03%~2.72%。铅:脱色土、磷酸、液碱在方法检出限分别为0.24、0.07、0.48的基础上,其加标回收率分别为90.5%~90.8%、92.0%~102%、93.7%~102%,RSD(n=3)分别为0.97%~4.45%、3.41%~7.36%、2.16%~3.90%。以上方法操作简便、重复性好、检出限低,结果准确、可靠,具有应用前景。 展开更多
关键词 原子荧光光度计 原子吸收仪 脱色土 磷酸 液碱 总砷
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Assessment of Long Term UV Radiation Measured by the Brewer Spectrophotometer in Hong Kong during 1995-2005 被引量:2
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作者 T.J. Wang K.S. Lam +1 位作者 Q. Liu X.M. Wang 《Atmospheric and Climate Sciences》 2011年第1期9-17,共9页
Time series of daily UV radiation measured by the ground-based Brewer spectrophotometer #115 in Hong Kong during 1995-2005 were studied through statistics analysis, with focus on the variability and long term changes ... Time series of daily UV radiation measured by the ground-based Brewer spectrophotometer #115 in Hong Kong during 1995-2005 were studied through statistics analysis, with focus on the variability and long term changes in relation to total ozone, clouds and AOD (Aerosol Optical Depth). The 11-year mean UV daily dose is 2644±262 J/m2, with maxima(3311 J/m2) in 2000 and minima (2415 J/m2) in 2002. The data were compared with that from TOMS (Total Ozone Mapping Spectrometer) Version 8 and show general agreement between the two. However, the Brewer UV measurement is about 10% lower compared to TOMS data. Apart from the common-known strong seasonal cycle, 26 month periodical was resolved by use of wavelet analysis, which was believed to be associated with quasi-biennial oscillation (QBO) of general circulation. In cloudy days, the annual mean UV daily dose decrease 3.5% to 44.5% compared to clear days. It was also found that surface UV irradiance has close relation to air pollution. Under clear sky condition, 1% AOD increase will lead to 0.2% UV decrease. While global UV radiation increase due to the worldwide observed ozone depletion, investigations indicate that this trend is not significant in Hong Kong during the last 11 years. The possible causes can be attributed to the compensative effect from two aspects. One is the increase of UV resulting from the reduction of clouds with rate of 0.56/10 yr. The other is the decrease of UV due to the enhancement of total ozone and AOD with a rate of 4.23 DU/10 yr and 0.33/10 yr, respectively. 展开更多
关键词 UV RADIATION Brewer spectrophotometer TOMS Hong Kong
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A Novel Chip-based Spectrophotometer for Online Detection
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作者 Haoyuan Cai Min-Hsien Wu Zheng Cui 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期346-348,共3页
A chip-based spectrophotometer integrated with optical fiber is successfully demonstrated.Grade concentration of lactate solution flowed through the chip to perform an online detection.The response time (100s)and Limi... A chip-based spectrophotometer integrated with optical fiber is successfully demonstrated.Grade concentration of lactate solution flowed through the chip to perform an online detection.The response time (100s)and Limit of Detection (LOD, 50mg/L)of the device were measured.This device shows comparable performance with traditional commercial instrument, while greatly decreases the sample requirement per detection and reduces the size of total system,introducing a novel method for real-time detection. 展开更多
关键词 spectrophotometer optical fiber online detection
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Determination of Thioglucoside in Cabbage by Using the Ultraviolet-visible Light Spectrophotometer
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作者 WANGJing WANGQing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2000年第2期149-157,共9页
The ultraviolet-visible light spectrophotometer method was adopted to determine thioglucoside in cabbage with the seeds.Individual plant of cabbage was used as test materials,palladium chloride as complexing agent and... The ultraviolet-visible light spectrophotometer method was adopted to determine thioglucoside in cabbage with the seeds.Individual plant of cabbage was used as test materials,palladium chloride as complexing agent and sodium cellulose glycolate as dispersing agent.The results showed that palladiumd thioglucoside method could be taken as a quick,easy and precise quantitative analysis method to determine thioglucoside in cabbage. 展开更多
关键词 Ultraviolet visible light spectrophotometer method CABBAGE thioglucoside determination method
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Spectrophotometer standardization in UV-Vis spectral region
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作者 Alaa-Eldin A Abd-Elmageed Essam M Elmoghazy Fatma Elsharkawy 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第1期40-43,共4页
Ultraviolet-visible(UV-Vis)spectrophotometry is commonly used in analytical laboratories for qualitative and quantitative analyses.To make the data obtained reliable,an experimental instrument must be calibrated.Nat... Ultraviolet-visible(UV-Vis)spectrophotometry is commonly used in analytical laboratories for qualitative and quantitative analyses.To make the data obtained reliable,an experimental instrument must be calibrated.National Institute for Standards(NIS)in Egypt builds up aphotometric method to ensure the competence of absorbance and transmittance to the standard international and national requirements.This paper presents an instrument for UV-Vis measurement,discusses the factors affecting measurement reliability and estabishes the uncertainty model including correspoding measurement parameters. 展开更多
关键词 spectrophotometer STANDARDIZATION ABSORBANCE UNCERTAINTY
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Determination of Palladium II in 5% Pd/BaSO<sub>4</sub>by ICP-MS with Microwave Digestion, and UV-VIS Spectrophotometer
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作者 Y. Yildiz M. Kotb +3 位作者 A. Hussein M. Sayedahmed M. Rachid M. Cheema 《American Journal of Analytical Chemistry》 2019年第4期127-136,共10页
Determination palladiums have been reported 5% (w/w) Pd/BaSO4 known as Rosenmund Catalyst. The determination of palladium II known as Rosenmund Catalyst is always an expensive procedure usually involving procedures su... Determination palladiums have been reported 5% (w/w) Pd/BaSO4 known as Rosenmund Catalyst. The determination of palladium II known as Rosenmund Catalyst is always an expensive procedure usually involving procedures such as flame atomic absorption spectrophotometry, emission spectrometry, and many spectrophotometric methods. In this study, palladium II in 5% Pd/BaSO4, was synthesized and employed to develop an extractive UV-Visible Spectrophotometric, and an inductively coupled plasma mass spectrometry ICP/MS methods for the determination of palladium II. Specification for Pd is 4.85% to 5.10%;the result was 4.97% for the UV-Visible spectrophotometer and 4.90% for the ICP/MS. Both results meet the requirements. 展开更多
关键词 PALLADIUM DETERMINATION 5% PALLADIUM Barium Sulfate Inductively Coupled Plasma Mass Spectrometry UV-VISIBLE spectrophotometer Microwave Digestion
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Transmittance Spectrum of Unbranded Sunglasses Using Spectrophotometer
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作者 Huseyin Gursoy Hikmet Basmak +1 位作者 Hamza Esen Ferhan Esen 《Open Journal of Ophthalmology》 2015年第1期1-5,共5页
Background: The sunglass standards are not strictly implemented in many countries except Aus-tralia. The purpose of the study was to evaluate the optical properties of unbranded sunglasses for light transmittance. Met... Background: The sunglass standards are not strictly implemented in many countries except Aus-tralia. The purpose of the study was to evaluate the optical properties of unbranded sunglasses for light transmittance. Methods: Unbranded sunglasses with no information about their specifications were included. They were allocated to two groups based on their prices;the ones > 25 US$ (Group A) and the cheaper ones (Group B). Their transmittance spectrum was measured between 190 nm and 900 nm using a double beam scanning spectrophotometer. The European standard for sunglasses was used to evaluate their compliance regarding ultraviolet radiation (UVR) transmittance and minimum requirement for wearing when driving. Results: Thirty-eight sunglasses (Group A = 20 and Group B = 18) were evaluated. Four sunglasses in each group were non-compliant. Percentage transmittance of visible light was <8% in five sunglasses of Group A and in three of Group B, so these were not appropriate to wear when driving. Totally six sunglasses of Group A and five of Group B were non-compliant and/or inappropriate to wear when driving. Conclusions: Based on our findings about their UVR protection and visible light transmittance %, eye care professionals must warn people against the use of unbranded sunglasses without any information about their specifications. 展开更多
关键词 Sunglass spectrophotometer TRANSMITTANCE SPECTRUM ULTRAVIOLET Radiation VISIBLE Light
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The Effectiveness of a Portable Fluorescence Spectrophotometer for Early Detection of Oral Cancer
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作者 Katsuhiro Asaka Akira Fukatsu Chiaki Komine 《Open Journal of Stomatology》 2022年第1期30-31,共12页
<strong>Purpose:</strong> To investigate whether photodynamic diagnosis (PDD) using a portable fluorescence spectrophotometer (FC-1) can easily and objectively discriminate between normal and tumor cells a... <strong>Purpose:</strong> To investigate whether photodynamic diagnosis (PDD) using a portable fluorescence spectrophotometer (FC-1) can easily and objectively discriminate between normal and tumor cells at the dental chairside, and to further compare it with PDD that requires speculum examination by focusing on protoporphyrin IX (PPIX). <strong>Methods: </strong>Three cell lines (2 human oral squamous cell carcinoma-derived cell lines, HSC-2 and HSC-3 cells, and oral keratinocytes, HOK cells) were cultured. 5-Aminolevulinic acid hydrochloride (5-ALA) and deferoxamine mesylate (DFO) were mixed in DMEM, and the mixture was set to Control (DMEM only) and PDD (5-ALA+DFO) groups. And then, a fluorescence was measured under room temperature (RT) and 37&deg;C (Incubation) by using FC-1. In this study, the two conditions were combined with the Control and PDD groups to form the Control/RT, Control/Incubate, PDD/RT, and PDD/Incubate groups. Additionally, the amount of singlet oxygen (1O2) generated by irradiation with 405 nm LED was measured using electron spin resonance spectroscopy to detect PPIX in the cell supernatant after 24 hours. <strong>Results:</strong> In HSC-2 and HSC-3, the fluorescence intensity values increased significantly at 2 hours between the Control/RT and PDD/RT groups. In addition, there was a significant difference between HSC-2 and HSC-3 compared to HOK. In all cell lines, the fluorescence intensity values of the PDD/Incubate group were significantly higher than those of the PDD/Control group. The amount of <sup>1</sup>O<sub>2</sub> generated by 405 nm LED irradiation was higher in the cell supernatants of all cell lines in the order of Control/RT < Control/Incubate < PDD/RT < PDD/Incubate group, and HSC-3 in the PDD/Incubate group showed a significant increase compared to HOK. <strong>Conclusion: </strong>It is suggested that PDD using FC-1 can clearly distinguish between normal cells and tumor cells in vitro studies using cell lines at 2 hours under 37&deg;C, and it can detect not only intracellular PPIX, but also extracellular PPIX. 展开更多
关键词 Photodynamic Diagnosis Portable Fluorescence spectrophotometer Oral Cancer Protoporphyrin IX
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Hyper Gravity-Induced Transients in <i>Phycomyces</i>as Measured by Single Beam Spectrophotometer on the Sounding Rocket TEXUS 50
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作者 Werner Schmidt 《Journal of Modern Physics》 2018年第2期273-286,共14页
In the first paper of two referring to the TEXUS 50 campaign using micro dual wavelength spectrometers (MDWS) we kinetically determined the threshold1 for GIACs (gravity-induced absorption changes) in Phycomyces to be... In the first paper of two referring to the TEXUS 50 campaign using micro dual wavelength spectrometers (MDWS) we kinetically determined the threshold1 for GIACs (gravity-induced absorption changes) in Phycomyces to be lower than 25 × 10&minus;3 g (http://file.scirp.org/pdf/JMP_2015082810060783.pdf). In this second paper, we attended measurement of GIAC-spectra. Unexpectedly, during the upwards movement, i.e. the hypergravity phase up to top acceleration values reaching 11.6 g at 35.4 s after liftoff we observed transient GIAC-spectra ranging from 380 to 750 nm. In addition, during the whole acceleration phase of 68.2 s, another component near 700 nm develops which remains stable during the whole “free fall trajectory parabola” for 381.3 s. The subsequent reentry of the rocket leads to extraordinary deceleration values up 37.8 g, completely destroying Phycomyces sporangiophores excluding their spectral measurement. During the microgravity phase and by centrifuge operation we were unable to detect any GIAC-spectra (in contrast to kinetic MDWS-measurements, first paper). 展开更多
关键词 MDWS (Micro-Dual Wavelength spectrophotometer) Single Beam spectrophotometer (SBS) Diode Array Spectrometer (USB-2000+ Ocean Optics) GIAC (Gravity-Induced Absorption Change) PHYCOMYCES blakesleeanus Sporangiophore Micro- and Hypergravity Texus 50 Sounding Rocket Graviperception. HYPER Gravity-Induced Transients
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THE LIGNIN CONTENT IN BLACK LIQUID OF STRAW AS-AQ BY ULTRAVIOLET SPECTROPHOTOMETER 被引量:1
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作者 HaiqiangShi BingyueLiu +2 位作者 XingqiangLi LongquanXu BeihaiHe 《天津科技大学学报》 CAS 2004年第A02期91-96,共6页
The measurement of lignin content in black liquid of straw AS-AQ by ultraviolet spectrophotometer(UV) is discussed in this paper. Different dilution multiple and contrast solutions have an effect on the measured resul... The measurement of lignin content in black liquid of straw AS-AQ by ultraviolet spectrophotometer(UV) is discussed in this paper. Different dilution multiple and contrast solutions have an effect on the measured results of the lignin content by UV. The calculation method for the absorption coefficient and the scanning spectrum property of liquor acidified by SO2 are introduced in this paper. 展开更多
关键词 紫外分光光度法 木质素 黑液 秸杆制浆液 多体稀释
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The Color of Natural Teeth Investigated by Visual Perception and Spectrophotometer
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作者 Teuta Pustina-Krasniqi Ariana Bytyci +5 位作者 Teuta Bicaj Enis Ahmedi Linda Dula Zana Lila Arlinda Dragusha Nexhmije Ajeti 《Open Journal of Stomatology》 2015年第2期26-35,共10页
The advantage of electronic devices is to eliminate the subjectivity. Based on individual capabilities, visual perception has its disadvantages. The aim of this study was to find out the possible shade difference betw... The advantage of electronic devices is to eliminate the subjectivity. Based on individual capabilities, visual perception has its disadvantages. The aim of this study was to find out the possible shade difference between the upper and lower teeth, visual perception versus spectrophotometry as well as proving that females are better in visual perception of colour matching. 82 subjects (dental students) of this study determined the color of each other’s natural teeth. The color of 1640 teeth (incisors, canines and premolars), was matched by visual perception and by Vita Easyshade spectrophotometer. The matching was focused on the middle third of buccal surfaces of the examined teeth. In this study, it was found that there was a difference of color between the teeth of the upper and lower jaw. The percentage of the accordance between two methods was 28.35% for all examined teeth. The color determination at central incisors showed the highest value of accordance 40.85%. Based on Vitapan 3D Mastershade, the most frequent color was 2M2. 展开更多
关键词 Teeth Color Visual Perception spectrophotometer Accordance
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