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红光补充UV-A对叶用莴苣倍半萜内酯类化合物的调控效应 被引量:1
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作者 田原源 查凌雁 +3 位作者 王座祺 段逸文 魏仕伟 章竞瑾 《中国蔬菜》 北大核心 2024年第3期51-58,共8页
叶用莴苣特有的苦味来源于倍半萜内酯类化合物,主要包括山莴苣苦素和莴苣苦素等。为探究紫外光对叶用莴苣生长和倍半萜内酯类化合物的调控作用,以纯红光(180μmol·m^(-2)·s^(-1))为对照,比较了补充UV-A(30μmol·m^(-2)&#... 叶用莴苣特有的苦味来源于倍半萜内酯类化合物,主要包括山莴苣苦素和莴苣苦素等。为探究紫外光对叶用莴苣生长和倍半萜内酯类化合物的调控作用,以纯红光(180μmol·m^(-2)·s^(-1))为对照,比较了补充UV-A(30μmol·m^(-2)·s^(-1))、UV-B(10μmol·m^(-2)·s^(-1))对7个叶用莴苣品种生长及倍半萜内酯类化合物的影响;并进一步分析了红外光添加UV-A补光强度(15、30、45μmol·m^(-2)·s^(-1))及补光时长(0、1、2、3、6、9 d)对叶用莴苣倍半萜内酯类化合物含量的影响。结果表明:添加UV-A处理可显著提高绿罗的地上部鲜质量,显著降低7个叶用莴苣品种的山莴苣苦素和莴苣苦素含量,分别降低了33%~74%和29%~60%。随着UV-A补光强度的增加,叶用莴苣中倍半萜内酯类化合物含量逐渐降低,且以添加30μmol·m^(-2)·s^(-1)UV-A处理2 d后叶用莴苣中山莴苣苦素含量迅速上升,处理3 d时达到峰值,随后逐渐降低;而莴苣苦素含量在处理2 d后基本保持逐步上升的趋势,处理6~9 d时略有下降。综上所述,红光补充适量的UV-A(30μmol·m^(-2)·s^(-1)、3~6 d),可在不影响生物量的基础上显著降低叶用莴苣中倍半萜内酯类化合物含量,从而减轻苦味。 展开更多
关键词 叶用莴苣 紫外光 uv-A 山莴苣苦素 莴苣苦素
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Determination of Total Lignanoids in Tangjiangshenkang Granules by Two-Wavelength Ultraviolet Spectrophotometry
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作者 Maolan TAN Qian JIANG +2 位作者 Lei ZHENG Yuting CHEN Jie LI 《Medicinal Plant》 CAS 2023年第4期35-37,共3页
[Objectives] To establish a determination method for the content of total lignanoids in Tangjiangshenkang granules. [Methods] Two-wavelength ultraviolet spectrophotometry (TWBS) was used to scan arctiin control soluti... [Objectives] To establish a determination method for the content of total lignanoids in Tangjiangshenkang granules. [Methods] Two-wavelength ultraviolet spectrophotometry (TWBS) was used to scan arctiin control solution, chlorogenic acid control solution and Tangjiangshenkang granule test solution in the range of 200-400 nm. In the ultraviolet scanning diagram of arctiin reference solution, the maximum absorption wavelength of 280 nm was determined as the determination wavelength λ 1, the detection wavelength in the ultraviolet scanning diagram of chlorogenic acid reference solution ( λ 1=280 nm) was determined, and 350 nm was the reference wavelength λ 2;the content of total lignosides in Tangjiangshenkang granules was determined with arctiin as the reference substance. [Results] The precision, accuracy, and durability of this method were fine. The concentration of arctiin was linearly correlated with the absorbance difference in the range of 0.007 95-0.071 55 mg/mL ( r =0. 999 9). The average recovery of arctiin was 100.8%, and the RSD value was 1.04% ( n =6). Calculated as arctiin, three batches of Tangjiangshenkang granules contain no less than 20% of total lignosides. [Conclusions] The method has the advantages of simple operation, good accuracy, precision and reliable stability. It can be used as the content determination and quality control method of total lignosides in Tangjiangshenkang granules. 展开更多
关键词 Tangjiangshenkang granule Fructus arctii Total lignanoids Two-wavelength ultraviolet spectrophotometry
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紫外发光二极管(UV-LED)技术对食品微生物灭活应用的研究进展
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作者 李金东 张忠杰 +3 位作者 祁智慧 尹君 金毅 唐芳 《粮油食品科技》 CAS CSCD 北大核心 2024年第2期151-158,共8页
紫外辐照是一种非热杀菌技术,汞蒸气紫外灯是现阶段用于食品卫生处理的主要设备,但受某些因素影响,汞灯的生产使用将逐渐变少,被环保节能的紫外发光二极管(UV-LED)取代是一种不可避免的趋势。本文根据UV-LED发光原理和多波长耦合应用的... 紫外辐照是一种非热杀菌技术,汞蒸气紫外灯是现阶段用于食品卫生处理的主要设备,但受某些因素影响,汞灯的生产使用将逐渐变少,被环保节能的紫外发光二极管(UV-LED)取代是一种不可避免的趋势。本文根据UV-LED发光原理和多波长耦合应用的特点,综述了对微生物灭活的机理、探究了影响灭活效果的因素(波长、紫外剂量和物料特性)、处理食品的灭菌效果以及对部分食品品质的影响,为UV-LED在食品领域的杀菌处理工艺和设备参数优化提供参考。 展开更多
关键词 紫外发光二极管(uv-LED) 微生物灭活 食品行业 非热杀菌技术
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柔性透明导电膜用UV胶的配方探讨
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作者 徐丹丹 秦苏琼 +2 位作者 陶军 瞿然 刘世国 《电子工业专用设备》 2024年第1期43-47,57,共6页
应用于柔性透明导电膜用UV胶压印技术,对柔性透明导电膜产品性能有重要作用,特别是胶的黏度、硬度、附着力、光学性能、耐水性、伸长率等对实现高精度印刷效果、导电膜柔韧性、透光率和稳定性都有重要的意义。根据柔性透明导电膜用UV胶... 应用于柔性透明导电膜用UV胶压印技术,对柔性透明导电膜产品性能有重要作用,特别是胶的黏度、硬度、附着力、光学性能、耐水性、伸长率等对实现高精度印刷效果、导电膜柔韧性、透光率和稳定性都有重要的意义。根据柔性透明导电膜用UV胶实用性能的要求,讨论了柔性透明导电膜用UV胶的配方成份。 展开更多
关键词 柔性透明导电膜 紫外光固化胶(uv胶) 压印
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UV-TiO_(2)-PS光催化降解煤化工废水中含氮有机物 被引量:2
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作者 陈莉荣 宛艳玉 +1 位作者 王瑞 谷振超 《化工环保》 CAS CSCD 北大核心 2023年第3期313-318,共6页
比较了由紫外光(UV)、TiO_(2)、H_(2)O_(2)、过硫酸盐(PS)组合而成的5种工艺对溶液中喹啉的光催化降解效果,分析了影响UV-TiO_(2)-PS降解喹啉的主要因素和降解机理,考察了该体系对吲哚和吡啶的降解效果。实验结果表明:相同条件下,5种体... 比较了由紫外光(UV)、TiO_(2)、H_(2)O_(2)、过硫酸盐(PS)组合而成的5种工艺对溶液中喹啉的光催化降解效果,分析了影响UV-TiO_(2)-PS降解喹啉的主要因素和降解机理,考察了该体系对吲哚和吡啶的降解效果。实验结果表明:相同条件下,5种体系对喹啉的去除效果依次为UV-TiO_(2)-PS>UV-TiO_(2)-H_(2)O_(2)>UV-PS>UV-H_(2)O_(2)>UV-TiO_(2),氧化剂H_(2)O_(2)或PS与UV-TiO_(2)联用,能提高喹啉去除率;在喹啉溶液初始质量浓度20 mg/L、TiO_(2)加入量1.2 g/L、PS加入量0.012 mol/L、初始pH 6.5的最佳工艺条件下,光反应150 min,喹啉去除率为97.07%,光反应180 min,TOC去除率为72.32%;在UV-TiO_(2)-PS降解喹啉的最佳工艺条件下,光反应150 min,该体系对吡啶和吲哚的去除率分别为41.12%和80.13%;UV-TiO_(2)-PS氧化降解喹啉过程中,活性物种的贡献依次为SO_(4)^(-)·>O_(2)-·>·OH>h^(+)。 展开更多
关键词 煤化工废水 喹啉 含氮杂环化合物 紫外光(uv) TiO_(2) 过硫酸盐(PS) 高级氧化
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Strain H_2-419-4 of Haematococcus pluvialis induced by ethyl methanesulphonate and ultraviolet radiation 被引量:9
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作者 孙延红 刘建国 +1 位作者 张晓丽 林伟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第2期152-156,共5页
Two strains H2-410 and H2-419 were obtained from the chemically mutated survivors of wild Haematococcus pluvialis 2 by using ethyl methanesulphonate (EMS). Strains H2-410 and H2-419 showed a fast cell growth with 13% ... Two strains H2-410 and H2-419 were obtained from the chemically mutated survivors of wild Haematococcus pluvialis 2 by using ethyl methanesulphonate (EMS). Strains H2-410 and H2-419 showed a fast cell growth with 13% and 20% increase in biomass compared to wild type, respectively. Then H2-419-4, a fast cell growth and high astaxanthin accumulation strain, was obtained by exposing the strain H2-419 to ultraviolet radiation (UV) further. The total biomass, the astaxanthin content per cell, astaxanthin production of H2-419-4 showed 68%, 28%, and 120% increase compared to wild H. pluvialis 2, respectively. HPLC (High Performance Liquid Chromatography) data showed also an obvious proportional variation of different carotenoid compositions in the extracts of H2-419-4 and the wild type, although no peak of carotenoids appeared or disappeared. Therefore, the main compositions in strain H2-419-4, like its wild one, were free of astaxanthin, monoester, and diester of astaxanthin. The asexual reproduction in survivors after exposed to UV was not synchronous, and different from the normal synchronous asexual reproduction as the mother cells were motile instead of non-motile. Interestingly, some survivors from UV irradiation produced many mini-spores (or gamete?), the spores moved away from the mother cell gradually 4 or 5 days later. This is quite similar to sexual reproduction described by Elliot in 1934. However, whether this was sexual reproduction remains questionable, as no mating process has been observed. 展开更多
关键词 雨生红球藻 EMS 紫外线辐射 虾青素
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非诺贝特酸胆碱缓释胶囊生产设备的UV法清洁验证 被引量:1
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作者 朱家乐 姜庆伟 金学军 《科技资讯》 2023年第7期64-68,共5页
为验证清洁操作完成后生产设备表面非诺贝特酸的残留量是否低于安全指标,建立了紫外可见分光光度法测定擦拭棉签的提取溶液中非诺贝特酸的含量。使用286 nm检测波长,1 cm吸收池,50%甲醇的溶剂。非诺贝特酸在0.95~14.25μg/mL浓度范围内... 为验证清洁操作完成后生产设备表面非诺贝特酸的残留量是否低于安全指标,建立了紫外可见分光光度法测定擦拭棉签的提取溶液中非诺贝特酸的含量。使用286 nm检测波长,1 cm吸收池,50%甲醇的溶剂。非诺贝特酸在0.95~14.25μg/mL浓度范围内线性关系良好。316不锈钢板、有机玻璃和硅胶的取样回收率分别为82.2%、75.8%、76.9%,RSD分别为9.47%、4.41%、4.06%。方法回收率为101.5%,RSD为1.05%。该UV法可用于生产设备上非诺贝特酸胆碱缓释胶囊残留物的清洁控制分析。 展开更多
关键词 非诺贝特酸 清洁验证 紫外可见分光光度法 残留物
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ULTRAVIOLET SPECTROPHOTOMETRY OF MULTI-COMPONENT MIXTURES USING ARTIFICIAL NEURAL NETWORKS
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作者 Xin Hua SONG Jian WANG Ru Qin YU 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第12期941-944,共4页
Three—layer back—propagation neural networks were used for processing the information provided by the ultraviolet spectra of five—component mixtures, affecting the simultaneous determination of the components with ... Three—layer back—propagation neural networks were used for processing the information provided by the ultraviolet spectra of five—component mixtures, affecting the simultaneous determination of the components with satisfactory results. 展开更多
关键词 ultraviolet spectrophotometry OF MULTI-COMPONENT MIXTURES USING ARTIFICIAL NEURAL NETWORKS
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紫外光固化油墨(UV油墨)在包装印刷中的应用 被引量:1
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作者 包军 胡炎炳 《塑料包装》 CAS 2023年第3期22-26,15,共6页
本文主要介绍了紫外光固化油墨的特点、组成、原理及光固化油墨使用的光源。同时,简要介绍了UV光固化油墨在胶印、丝网印刷、柔板印刷、凹版印刷中的应用情况,以及在使用过程中的注意事项。
关键词 uv油墨 包装印刷 紫外光固化
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阿伐那非片原研与仿制药的溶出度测定的UV方法学研究
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作者 单腾腾 潘海群 禹玉洪 《山东化工》 CAS 2023年第2期125-127,131,共4页
目的:比较阿伐那非片在5种不同介质中的溶出度,建立阿伐那非片的溶出度测定方法。方法:按照溶出度与释放度测定法(中国药典2020年版通则0931第二法(浆法))测定,照紫外-可见分光光度法(UV)进行检测,检测波长310 nm,选用溶出介质为pH值=1.... 目的:比较阿伐那非片在5种不同介质中的溶出度,建立阿伐那非片的溶出度测定方法。方法:按照溶出度与释放度测定法(中国药典2020年版通则0931第二法(浆法))测定,照紫外-可见分光光度法(UV)进行检测,检测波长310 nm,选用溶出介质为pH值=1.2的氯化钠盐酸溶液,溶出体积900 mL,转速为50 r·min^(-1),分别在5,10,15,20,30 min取样。结果:100,200 mg规格在15 min内溶出度均在85%以上;线性范围为4.43~26.57μg/mL,相关系数r为0.9999,截距百分比为0.04%,线性关系良好;平均回收率分别为100.20%(RSD=0.09%)、100.48%(RSD=0.17%)。结论:建立的溶出度测定方法适用于阿伐那非片溶出曲线的评估,可用于该产品的质量控制。 展开更多
关键词 紫外分光光度法 阿伐那非 溶出度
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IMPROVEMENT OF FLUORIMETRIC AND UV-VISIBLE SPECTROPHOTOMETRIC ASSAY METHODS FOR MEASURING NITRIC OXIDE AND/OR EDRF IN BLOOD
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作者 杨凡 刘朴 《Journal of Pharmaceutical Analysis》 CAS 1995年第2期203-203,共1页
The increasing importance of endothelium-derived relaxing factor(EDRF),which has now been identified as nitric oxide (NO),has been underscored by the eltlcidation of its role'in a growing number of normal and path... The increasing importance of endothelium-derived relaxing factor(EDRF),which has now been identified as nitric oxide (NO),has been underscored by the eltlcidation of its role'in a growing number of normal and pathophysiological processes. Therefore techniques for detection of nitric oxide should serve as useful tools in defining the role of nitric oxide to these processes.We have improved a simple, sensitive assay methods for determination of nitric oxide in blood, tissue, and other body fluids both by fluorometric and by ultraviolet-visible spectrophotometric measurements. Data obtained by floores cence and by UV-visible assay were correlated well (r=0. 9938, P<0. 0001 ).Linearity:0.1 ̄ 100μmol/L,r =0.9996,P<0.0001. The minimum detection limit were < 10pmol/L. Within-and between-run CVs were 2. 48%and 4. 62% (n = 10),respectively.Reference values for healthy adults(n=40) were(9.82 ± 1. 57) pmol/L. In conclusion:the methods is sensitive, specific,and precise. It is fairly rapid and simple to perform andrequires no pretreatment of sample, i. e., plasma and urine.The value can be obtained by fluorimeter and/or UV-visible spectrophotometer.The present method is sufficiently rapid and simple to make this a practical choice for many laboratories. 展开更多
关键词 nitric oxided endothelium-derived relaxing factor measurement fluorescence ultraviolet-visible spectrophotometry
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Ultraviolet metalens and metalens array of focused vortex beams
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作者 张金平 王焱 +5 位作者 袁欢 王泽豪 邓阳 黄承志 吴加贵 杨俊波 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期270-276,共7页
The solar-blind ultraviolet(UV)wavelength is particularly interesting within the range of 200 nm–300 nm.Here,we propose a focusing metalens,focusing vortex beam(VB)metalens and metalens array that specifically work i... The solar-blind ultraviolet(UV)wavelength is particularly interesting within the range of 200 nm–300 nm.Here,we propose a focusing metalens,focusing vortex beam(VB)metalens and metalens array that specifically work in the UV band to focus a beam or VB.Firstly,a high numerical aperture(NA)focusing metalens working at a wavelength of 214.2 nm was designed,and the NA reached 0.83.The corresponding conversion efficiency of the unit structure reached as high as 94%,and the full width at half maximum was only 117.2 nm.Metalenses with large NA can act as optical tweezers and can be applied to trap ultracold atoms and molecules.Secondly,a focused VB metalens in the wavelength range of200 nm–300 nm was also designed,which can convert polarized light into a VB and focus the VB simultaneously.Finally,a metalens array was developed to focus VBs with different topological charges on the same focal plane.This series of UV metalenses could be widely used in UV microscopy,photolithography,photonics communication,etc. 展开更多
关键词 metalens METAMATERIALS ultraviolet(uv) vortex beams
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Studies of Ce(Ⅲ)-ALC-F Interacting with Herring Sperm DNA by Electrochemical, Fluorimetric and UV-spectrophotometric Method
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作者 GuangHanLU WeiLIU ChuanYinLIU LiPingJIANG FengSONG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第4期443-446,共4页
Ce(Ⅲ)-ALC-F complex can react with hsDNA to form an electrochemically non-active supermolecular complex Ce(Ⅲ)-ALC-F-DNA in the buffer solution of (CH2)6N4(pH=4.9), which results in the decrease of the peak current o... Ce(Ⅲ)-ALC-F complex can react with hsDNA to form an electrochemically non-active supermolecular complex Ce(Ⅲ)-ALC-F-DNA in the buffer solution of (CH2)6N4(pH=4.9), which results in the decrease of the peak current of Ce(Ⅲ)-ALC-F. This method can be applied to determine DNA concentration. In addition, by using fluorimetric and UV-spectrophotometric methods with studies of denatured DNA and the effect of NaCl solution , it is also found that the binding mode is intercalation. 展开更多
关键词 Ce(Ⅲ)-ALC-F electrochemically non-active supermolecular complex herring sperm DNA(hsDNA) FLUORIMETRY uv-spectrophotometry intercalation.
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Effects of Inhabiting and Life Patterns on the UV Spectral Properties of Small Mammalian Herbivores’ Urine
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作者 Junnian Li 《Open Journal of Forestry》 2023年第1期32-44,共13页
It is well known that avian predators can use prey excretions such as urine and feces to track their prey, and the urine and feces of small mammalian herbivores can reflect ultraviolet (UV) light and emit fluorescent ... It is well known that avian predators can use prey excretions such as urine and feces to track their prey, and the urine and feces of small mammalian herbivores can reflect ultraviolet (UV) light and emit fluorescent light. There are still some debates as to whether UV visibility of small mammalian herbivores’ urine is used as a hunting cue by avian raptors. Some studies in Europe have demonstrated that diurnal raptors are capable of utilizing these cues to target key prey species. However, researchers in Australia have argued that raptors do not use the UV visibility of urine while hunting. To our knowledge, there are no reports from Asia concerning the ultraviolet spectral characteristics of small mammal herbivores’ urine. This study examined the UV spectral properties of urine from 6 small mammal herbivores species by comparing the UV reflectance and fluorescence spectra of urine from small mammalian herbivores living in plateau meadows, plateau shrubs, open marshland, farmland, and semi-desert grassland in China. In addition, we compared the UV spectral properties of urine from ground-dwelling species of rodents and subterranean species to determine whether ultraviolet visibility of small mammal herbivores’ urine could be used as a visual signal by Asian vole-eating raptors. The results showed that: 1) the SC<sub>370</sub> values of urine from four small mammal herbivores species were ordered as plateau pika (plateau meadow) > root voles (plateau bush) > reed voles (swampland) > Brandt’s vole (desert grassland);and 2) UV fluorescence peak intensity and the wavelengths of urine from ground-dwelling species (such as the root vole, plateau pika, or Brandt’s vole) were significantly higher than those of subterranean-dwelling species (mandarin vole and plateau zokor). These results indicate that UV visibility of small mammal herbivores’ urine may act as a visual cue for raptors. 展开更多
关键词 Rodents Urine ultraviolet (uv) Light FLUORESCENCE
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短波紫外线(UV-C)对贮藏蓝莓果实抗氧化活性的影响
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作者 徐方旭 刘泓远 +3 位作者 何茜 刘博佳 李冰鑫 张晋颖 《沈阳师范大学学报(自然科学版)》 CAS 2023年第1期49-57,共9页
评估短波紫外线(Ultraviolet-C,UV-C)在不同冷藏时间、货架期和贮藏温度下对蓝莓抗氧化活性变化的影响,可以为提高蓝莓品质的可行方法提供理论依据。结果表明,UV-C处理蓝莓的原花青素含量、总酚含量、总花青素含量、类黄酮含量和自由基... 评估短波紫外线(Ultraviolet-C,UV-C)在不同冷藏时间、货架期和贮藏温度下对蓝莓抗氧化活性变化的影响,可以为提高蓝莓品质的可行方法提供理论依据。结果表明,UV-C处理蓝莓的原花青素含量、总酚含量、总花青素含量、类黄酮含量和自由基清除能力随贮藏时间、货架期、贮藏温度及其相互作用而不同。随着货架期的延长,抗氧化活性逐渐下降,特别是对于长期冷藏的蓝莓,UV-C辐照显著延缓了样品中原花青素和总酚含量的下降,低温(5℃)能有效维持高水平的自由基清除能力。总之,贮藏时间、货架期和贮藏温度对UV-C处理蓝莓抗氧化活性的变化有不同程度的影响。 展开更多
关键词 蓝莓 短波紫外线 货架期 抗氧化活性
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UV激活S_(2)O_(8)^(2-)降解水中抗生素的研究进展
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作者 赵久妹 《辽宁师专学报(自然科学版)》 2023年第4期28-38,共11页
水中的抗生素种类较多,结构复杂,难以处理,对水生生态环境造成了威胁.紫外线(UV)除用于水中微生物的消毒之外,还能用于降解水中的有机物.总结归纳了抗生素的种类和结构特点,过硫酸盐的结构和性质,以及紫外线光源的类型;分析了UV激活S_(2... 水中的抗生素种类较多,结构复杂,难以处理,对水生生态环境造成了威胁.紫外线(UV)除用于水中微生物的消毒之外,还能用于降解水中的有机物.总结归纳了抗生素的种类和结构特点,过硫酸盐的结构和性质,以及紫外线光源的类型;分析了UV激活S_(2)O_(8)^(2-)降解水中抗生素的原理;指出了目前研究现状中存在的一些问题,并对未来的研究方向提出了展望.研究成果为紫外线/过硫酸盐系统应用于水中抗生素的处理提供理论支撑. 展开更多
关键词 紫外线 过硫酸盐 抗生素 高级氧化法 硫酸根自由基
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UV-VIS测定医疗设备涂料中六价铬的含量
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作者 费沁妮 李新寅 苏小军 《化工管理》 2023年第18期51-53,共3页
六价铬虽然被广泛使用在很多行业中,但它不仅是一种常见的致癌物质,而且对环境具有持久性的危害。因此针对医疗设备所使用的涂料,检测其中六价铬(Cr(VI))的含量具有非常重要的意义。文章通过碱性消解液对医疗设备涂料样品进行超声提取,... 六价铬虽然被广泛使用在很多行业中,但它不仅是一种常见的致癌物质,而且对环境具有持久性的危害。因此针对医疗设备所使用的涂料,检测其中六价铬(Cr(VI))的含量具有非常重要的意义。文章通过碱性消解液对医疗设备涂料样品进行超声提取,然后在波长540 nm处,使用紫外可见分光光度法(UV-VIS)对样品提取液中的Cr(VI)含量进行检测。本方法的线性相关系数大于0.999,六价铬的检出限可达到0.002 89 mg/L,加标回收率为91.4%~94.5%,相对标准偏差为1.69%,重复性好,测量结果准确,精密度高,操作简单,为医疗设备生产企业的产品质量控制、生产分析、原材料筛选以及安全性评估提供了良好的检测手段。 展开更多
关键词 六价铬 紫外可见分光光度法 涂料 医疗设备
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UV法COD监测仪在城市污水管网中的应用
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作者 赵云飞 赵丛丛 任紫嫣 《建设科技》 2023年第10期26-31,共6页
紫外分光光度法(UV法)用于污水管网节点的化学需氧量(COD)在线监测是一种简单快速的物理测量方法,与传统化学法相比经济、环保。本研究对北方某城市污水处理厂进水主干管上游水质COD指标进行实时监测,并对UV法监测数据进行量值溯源。结... 紫外分光光度法(UV法)用于污水管网节点的化学需氧量(COD)在线监测是一种简单快速的物理测量方法,与传统化学法相比经济、环保。本研究对北方某城市污水处理厂进水主干管上游水质COD指标进行实时监测,并对UV法监测数据进行量值溯源。结果表明,UV法适用于成分相对稳定的污水COD的快速测定,需结合待测水样的国标法检测数据来建立校准模型,校准后的数据能够达到较高的数据精度。 展开更多
关键词 紫外分光光度法 化学需氧量 污水管网
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紫外分光光度法测定歧化松香中去氢枞酸含量的干扰因素研究
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作者 王宏晓 沈娟章 +1 位作者 马艳 谭卫红 《林产化学与工业》 CAS CSCD 北大核心 2024年第3期30-36,共7页
利用液相色谱仪、制备液相色谱仪、气相色谱质谱联用仪,对歧化松香(DR)中去氢枞酸(DA)紫外光谱测定方法的干扰因素进行了详细研究。测定的市售不同省份的5个样品中有2个主要干扰物质,进一步定性,确定干扰物质1为6,8,11,13-枞四烯酸(ATA)... 利用液相色谱仪、制备液相色谱仪、气相色谱质谱联用仪,对歧化松香(DR)中去氢枞酸(DA)紫外光谱测定方法的干扰因素进行了详细研究。测定的市售不同省份的5个样品中有2个主要干扰物质,进一步定性,确定干扰物质1为6,8,11,13-枞四烯酸(ATA),干扰物质2为混合物,主要检出物为去氢枞醛(D)和枞酸(AA)。采用二阶导数光谱法和偏最小二乘(PLS)法对紫外光谱数据进行分析,以消除去氢枞酸紫外分光光度法的干扰,结果表明:PLS法比二阶导数光谱法误差更小,能够同时消除多种干扰因素,使测试结果更加接近真实值。 展开更多
关键词 歧化松香 紫外可见分光光度法 干扰因素 偏最小二乘法
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超声提取法对杜仲不同“发汗”品经不同加工炮制后总黄酮成分的影响研究
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作者 许义红 魏啸宇 +2 位作者 张林甦 唐方方 李香 《广东化工》 CAS 2024年第11期47-49,共3页
目的:比较杜仲生品及不同发汗品经四种不同炮制方法对杜仲总黄酮成分的影响,为杜仲加工炮制提供依据。方法:将杜仲生品及不同发汗品经姜制、酒制、盐制、蜜制四种炮制后制备各样品,用芦丁作对照品,采用紫外分光光度法,于510 nm波长处,... 目的:比较杜仲生品及不同发汗品经四种不同炮制方法对杜仲总黄酮成分的影响,为杜仲加工炮制提供依据。方法:将杜仲生品及不同发汗品经姜制、酒制、盐制、蜜制四种炮制后制备各样品,用芦丁作对照品,采用紫外分光光度法,于510 nm波长处,分别测定不同发汗品经四种炮制后超声提取物中的总黄酮含量。结果:杜仲生品及不同发汗品不同炮制方法对杜仲总黄酮的含量有影响,烘至半干后“发汗”品(E5)酒制品总黄酮含量最高。结论:若以杜仲总黄酮为主的药理作用进行临床应用时,建议杜仲采取烘至半干“发汗”后采用酒制处理的加工炮制方法。 展开更多
关键词 杜仲 总黄酮 发汗 炮制 紫外分光光度法
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