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西红花吸光度测定方法改进及其品质快速评价 被引量:2
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作者 李庆 闫晓剑 +5 位作者 黄永亮 彭善贵 赵小勤 周晓英 罗霄 文永盛 《中国现代中药》 CAS 2021年第4期655-659,共5页
目的:改进《中华人民共和国药典》(以下简称《中国药典》)2015年版中西红花吸光度测定方法,并以吸光度值评价西红花质量。方法:改变提取方法和稀释倍数,考察不同温度及光照与否对测试液稳定性的影响。用改进后的测定方法测定西红花吸光... 目的:改进《中华人民共和国药典》(以下简称《中国药典》)2015年版中西红花吸光度测定方法,并以吸光度值评价西红花质量。方法:改变提取方法和稀释倍数,考察不同温度及光照与否对测试液稳定性的影响。用改进后的测定方法测定西红花吸光度值,并对不同产地、不同等级的西红花质量进行比较。结果:甲醇超声提取45 min可达到《中国药典》2015年版索氏提取方法效果,稀释倍数由1000倍改为1667倍,可使吸光度值处于0.3~0.7的样品占比由28%提高至88%,检测应在避光条件下测定。不同产地、不同级别的西红花吸光度值之间差异有统计学意义(P<0.05)。结论:改进后的吸光度值测定方法更加快速、科学、准确,可用于西红花质量控制和评价,是高效液相色谱法的有效补充。 展开更多
关键词 西红花 吸光度测定 提取方法 稳定性 稀释倍数 品质评价
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产肠毒素大肠杆菌的生长曲线测定及活菌计数
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作者 付瑞 秦庆颜 +2 位作者 王宇容 孙丽 郑文娜 《中文科技期刊数据库(引文版)医药卫生》 2023年第9期24-27,共4页
判断ETEC的对数生长期,并探讨OD600值与ETEC活菌数之间的相关性。方法 采用分光光度计测定ETEC菌液不同生长时间的OD600值,绘制ETEC生长曲线;将OD600值为0.8-1.0的ETEC菌液作为原菌液,将原菌液按不同稀释倍数进行稀释,分别测定其相应的O... 判断ETEC的对数生长期,并探讨OD600值与ETEC活菌数之间的相关性。方法 采用分光光度计测定ETEC菌液不同生长时间的OD600值,绘制ETEC生长曲线;将OD600值为0.8-1.0的ETEC菌液作为原菌液,将原菌液按不同稀释倍数进行稀释,分别测定其相应的OD600值,并涂血琼脂平板,培养后对菌落进行计数。结果 培养30-150 min为ETEC的对数生长期;OD600值与ETEC活菌数呈线性相关,线性回归方程为y=0.23+0.131x,R2=0.96,OD600值(x),菌落数目(y×109)∕ml。结论 运用OD值法可以准确、简便的判断ETEC的对数生长期及对菌液中的产肠毒素大肠杆菌进行活菌计数。 展开更多
关键词 光度测定 生长曲线 活菌计数 产肠毒素大肠杆菌
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微生物法测定婴幼儿奶粉中泛酸含量的研究 被引量:2
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作者 贺燕 钟菲菲 +2 位作者 王晓庆 徐文泱 杨滔 《食品与机械》 北大核心 2022年第6期77-81,共5页
目的:优化微生物法测定婴幼儿奶粉中泛酸含量的测定条件,为泛酸检测国标法的后续修订提供试验数据。方法:分析了国标法测定泛酸过程中有待改善的问题,并对检测过程中的菌液制备、前处理及吸光度测定等关键步骤进行重点探讨研究。结果:A... 目的:优化微生物法测定婴幼儿奶粉中泛酸含量的测定条件,为泛酸检测国标法的后续修订提供试验数据。方法:分析了国标法测定泛酸过程中有待改善的问题,并对检测过程中的菌液制备、前处理及吸光度测定等关键步骤进行重点探讨研究。结果:ATCC和CICC来源的植物乳杆菌均可用于测定泛酸;以直接接种透光率为80%的菌液至测试管中,或以5mL菌液添加至400mL灭菌测试培养基,得到的标准曲线及测定的样品结果最佳;直接提取法的结果较水解法高;酶标仪和紫外分光光度法测定结果相对偏差在5%以内,其中酶标仪法测定加标回收率达到了96.9%,相对标准偏差(RSD)为4.95%,更具优势。结论:微生物法测定泛酸的关键步骤经优化后,可简化操作过程,提高测定样品的准确性,其优化条件可作为泛酸检测国标法的后续修订的参考依据。 展开更多
关键词 微生物法 婴幼儿乳粉 泛酸 菌液制备 前处理 吸光度测定
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药物溶血实验检测方法研究进展 被引量:5
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作者 冷毅伦 刘建莉 +3 位作者 徐佳奇 马佳凤 曾如梦 林恒秀 《安徽医药》 CAS 2017年第3期424-427,共4页
对现阶段多种药物溶血实验方法进行了对比研究,并依据红细胞破坏量、红细胞内容物释放等进行分类,发现干化学法替代氰化高铁法、4-氨基安替比林法替代甲联苯胺法等进行溶血试验可提高结果的精确度,更加便利和高效。由此,为药物生物安全... 对现阶段多种药物溶血实验方法进行了对比研究,并依据红细胞破坏量、红细胞内容物释放等进行分类,发现干化学法替代氰化高铁法、4-氨基安替比林法替代甲联苯胺法等进行溶血试验可提高结果的精确度,更加便利和高效。由此,为药物生物安全性评价提供参考方法和依据。 展开更多
关键词 血液学试验 分光光度 紫外线 吸光度测定 胶体金 免疫层析法
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不过滤水样中铁离子的反射吸光光度法研究 被引量:2
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作者 张达文 马高恒 +1 位作者 梁英 张敏 《分析试验室》 CAS CSCD 北大核心 2018年第5期568-573,共6页
自制了与商品化吸光光度计匹配的反射吸光度测定装置,并利用该装置研究了水样浊度对铁(Ⅱ)-邻菲罗啉络合物反射吸光度的影响。实验结果表明,当铁离子质量浓度在0~10.00 mg/L范围内时,具有一定浊度(T)的试样按标准方法显色后,试样浊度的... 自制了与商品化吸光光度计匹配的反射吸光度测定装置,并利用该装置研究了水样浊度对铁(Ⅱ)-邻菲罗啉络合物反射吸光度的影响。实验结果表明,当铁离子质量浓度在0~10.00 mg/L范围内时,具有一定浊度(T)的试样按标准方法显色后,试样浊度的反射吸光度(AT)与铁(Ⅱ)-邻菲罗啉络合物的反射吸光度具有加和性。通过大量实验数据,推导出AT=4.49×10^(-4)T+0.0264(R^2=0.9774,n=20)。基于此,建立了不过滤水样中铁离子的反射吸光光度法,即:水样无需过滤,按标准方法加入试剂显色,测得吸光度AS;同时,用以上推导公式计算AT;以AS-AT代入标准曲线方程即可计算待测水样中的铁离子质量浓度。采集4个实际河水水样为基底,随机加入适量铁离子标准溶液,分别用本论文研究的方法和标准方法测定水样中的铁离子质量浓度,两者的测定结果无显著差异。 展开更多
关键词 不过滤水样 反射光度 铁离子 反射吸光度测定装置
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儿童青少年体成分不同测量方法比较 被引量:8
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作者 黄锟 陶芳标 +3 位作者 任安 阙敏 何春燕 王君 《中国公共卫生》 CAS CSCD 北大核心 2007年第11期1303-1305,共3页
目的采用人体测量学、生物电阻抗法(bioelectrical impedance analysis,BIA)、双能X线吸收法(dual-en-ergy X-ray absorptiomery,DXA)对儿童进行体成分测量并探讨相关性与一致性。方法以62名8-15岁儿童青少年为研究对象,采用人体测... 目的采用人体测量学、生物电阻抗法(bioelectrical impedance analysis,BIA)、双能X线吸收法(dual-en-ergy X-ray absorptiomery,DXA)对儿童进行体成分测量并探讨相关性与一致性。方法以62名8-15岁儿童青少年为研究对象,采用人体测量、BIA和DXA法进行身体成分测定。结果3种方法所测的体成分指标与体质指数(BMI)均呈较强正相关(r=0.700-0.816);腰围、腰臀比、腹部皮脂厚度与DXA所测的躯干脂肪含量和脂肪百分含量呈高度正相关(r分别为0.847,0.726和0.885)。体成分测量指标在长岭公式法与DXA之间,BIA与DXA之间均存在较强相关联性。对于大部分个体而言,运用长岭公式低估了体脂百分含量,BIA方法在各体脂水平均低估了个体的体脂百分含量。结论腰围等简单人体测量指标在中心性体脂分布上有一定应用价值。长岭公式方法与BIA法均不同程度地低估了个体的实际体脂百分含量,与DXA的一致性较差,需创造条件扩大样本含量进行验证。 展开更多
关键词 体质指数 皮肤壁厚度 电阻抗/诊断应用 吸光度测定 X线
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不同渗透压氯化钠溶液对不同种属动物红细胞的影响 被引量:1
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作者 喻雨 任萌 +2 位作者 孙双勇 李韶勇 董卫莉 《广东化工》 CAS 2022年第9期5-7,共3页
目的:探究四种不同种属来源的实验动物红细胞在不同浓度氯化钠溶液中的溶血情况。方法:分别使用日本大耳白兔,SD大鼠,豚鼠,绵羊的2%红细胞悬液在不同浓度的氯化钠溶液中孵育,再通过目视观察和全波长酶标仪测定吸光度判定实验结果。结果... 目的:探究四种不同种属来源的实验动物红细胞在不同浓度氯化钠溶液中的溶血情况。方法:分别使用日本大耳白兔,SD大鼠,豚鼠,绵羊的2%红细胞悬液在不同浓度的氯化钠溶液中孵育,再通过目视观察和全波长酶标仪测定吸光度判定实验结果。结果:在较低浓度氯化钠溶液(0.1%~1%)中,豚鼠红细胞发生溶血的氯化钠浓度范围最小,SD大鼠、日本大耳白兔次之,绵羊红细胞发生溶血的氯化钠浓度范围最大。在较高浓度氯化钠溶液(2%~20%)中,日本大耳白兔红细胞发生溶血的氯化钠浓度范围最小,大鼠次之,豚鼠和绵羊相似,红细胞发生溶血的氯化钠浓度范围较大。结论:在渗透压较低的溶液中,豚鼠红细胞对渗透压变化耐受性强;在渗透压较高的溶液中,日本大耳白兔红细胞对渗透压变化耐受性强;绵羊红细胞在高渗和低渗环境中对渗透压变化的耐受性都较差。 展开更多
关键词 体外溶血 氯化钠溶液 动物红细胞 渗透压 吸光度测定 目视观察法
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Determination of the Trace Element Contents in Plants Using Atomic Absorption Spectrophotometer 被引量:37
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作者 高淑云 《Agricultural Science & Technology》 CAS 2008年第2期6-9,共4页
The aim of the study is to investigate the contents of trace element Se, Cd, Pb in three plants including burdock, ginkgol and garlic via graphite furnace atomic absorption and standard addition method. The results sh... The aim of the study is to investigate the contents of trace element Se, Cd, Pb in three plants including burdock, ginkgol and garlic via graphite furnace atomic absorption and standard addition method. The results show that Se in burdock stem, skin and leaf are 32.40, 48.63, 38.10 μg/g, respectively; Cd in burdock stem, skin and leaf are 0. 160 0, 0. 300 0, 0. 140 0 μg/g, respectively; Cd in burdock stem, skin and leaf are 2. 020, 3. 960, 2. 410 μg/g, respectively. In the ginkgo and ginko leaf, Se contents are 17.63 and 16.91 μg/g, respectively ; for Cd are 0. 181 0 and 0.2020μg/g, respectively ; for Pb are 3. 572 and 4. 021 μg/g, respectively. In garlic, Se, Cd and Pb are 73. 900 0, 6. 900 0 and 0. 390 0, respectively. All the standard deviations of measured results are below 2.3%, recovery rate are from 99% to 101%. 展开更多
关键词 Trace elements GFT AAS BURDOCK GINKGO GARLIC
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Preliminary Identification of Red Pigment and Positive Correlation between the Contents of Red Pigment and Total Saponins of Panax notoginseng Fruits 被引量:1
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作者 赵昶灵 陈中坚 +3 位作者 陈文龙 支伟特 魏富刚 宋德功 《Agricultural Science & Technology》 CAS 2012年第9期1891-1895,共5页
[Objective] This study aimed to identify red pigment of Panax notoginseng fruits and explore the correlation between pigment content and total saponins of the fruits. [Method] The red pigment of Panax notoginseng frui... [Objective] This study aimed to identify red pigment of Panax notoginseng fruits and explore the correlation between pigment content and total saponins of the fruits. [Method] The red pigment of Panax notoginseng fruits was preliminarily identi- fied with specific color reactions and UV-vis spectra, and the contents of the pigment and total saponins were determined via spectrophotometry. [Result] The red hues of the fruits were contributed by anthocyanins and/or the anthocyanidins. The contents of anthocyanins and total saponins of the fruits both decreased along with thinning of the red hues. The content difference of the anthocyanins in fruits with different red hues reached extremely significant level, but that of total saponins just reached significant level. [Conclusion] The red pigment of P. notoginseng fruits is anthocyanins which are of extremely significant positive correlation with total saponins in contents. 展开更多
关键词 Panax notoginseng fruits Red pigment Anthocyanins Total saponins Content correlation
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THE STUDY OF INTERACTION OF SOLID-LIQUID ADSORPTION SYSTEM BY USING THE FLOW INJECTION-SPECTROPHOTOMETRY SYSTEM 被引量:2
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作者 HE Guangping CHEN Bingren +1 位作者 XU Huiling LIU Guihua 《Chinese Journal of Reactive Polymers》 2001年第2期154-159,共6页
The flow injection analysis was firstly used for studying a solid-liquid adsorption system, and the dynamics process in the adsorption of dyestuff with regenerable chitin was traced by an online method of flow injecti... The flow injection analysis was firstly used for studying a solid-liquid adsorption system, and the dynamics process in the adsorption of dyestuff with regenerable chitin was traced by an online method of flow injection-spectrophotometry. Experimental results indicate that there is a linearization between the tested signals and the height of peaks with reciprocity coefficient 0.9999 by using the flow injection-spectrophotometry system to study the dynamics adsorption process in solidliquid system. The method shows a good stability and reproducibility. It provides a new method for the studies on adsorption dynamics in solid- liquid system. 展开更多
关键词 Flow injection-spectrophotometry Regenerable chitin Solid-liquid adsorption Acid chrome blue K
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COMPARISON OF BONE MASS IN FOREARM,LUMBAR VERTEBRA AND HIP BY SINGLE AND/OR DUAL ENERGY X-RAY ABSORPTIOMETRY
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作者 秦明伟 林守清 +4 位作者 宋忠良 田均平 陈凤领 严洪珍 葛秦生 《Chinese Medical Sciences Journal》 CAS CSCD 1999年第2期117-120,共4页
OBJECTIVE: Bone mineral density (BMD) was measured in normal Chinese women with single X-ray absorptiometry (SXA) and dual energy X-ray absorptiometry (DEXA). These two methods were compared to evaluate the sensitivit... OBJECTIVE: Bone mineral density (BMD) was measured in normal Chinese women with single X-ray absorptiometry (SXA) and dual energy X-ray absorptiometry (DEXA). These two methods were compared to evaluate the sensitivity in reflecting bone loss. METHODS: Measurements were performed in 300 women aged 20 to approximately 79 (5 for each age). The 8mm distal, 1/4 distal, ultra distal site of the nondominant forearm were measured with SXA; the AP spine (L2-4), right femoral neck (Neck), Ward's triangle (Ward) and trochantor (Troch) were measured with DEXA. Ten women had 5 repeated measurements to evaluate the reproducibility of the equipments. RESULTS: The BMD peak for Neck and Ward was found between age 20 to approximately 29, for ultra distal and L2-4 at age 30 to approximately 39, for 8mm distal, 1/4 distal and Troch at age 40 to approximately 49. After reaching the peak values, BMD at all sites decreased with increasing age. The highest rate of yearly loss of BMD was at 8mm distal. Results of measurement showed significant correlation between SXA and DEXA. Comparing with premenopausal women, the bone loss rate in postmenopausal women was faster and highest up to 11 to approximately 15 years and the highest rate was at the Ward. CONCLUSION: The present study gives the normal values of BMD at seven sites for normal Chinese women. The ages of BMD peak were different at seven sites. The yearly loss of BMD was highest at 8mm distal, it seemed to be the sensitive region for bone loss with age. The postmenopausal women had highly significantly loss bone mass than the premenopausal women. Comparing with premenopause, postmenopause BMD for Ward's triangle with DEXA seemed to be most sensitive to the effect of menopause. 展开更多
关键词 bone density osteoporosis post menopause densitometry X ray
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Determination of Salt Impurities in MDEA Solution Used in Desulfurization of Highly Sulphurous Natural Gas
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作者 Liu Yucheng Zhang Bo +2 位作者 Chen Mingyan Wu Danni Zhou Zheng 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第3期25-31,共7页
The foaming phenomenon of N-methyldiethanolamine(MDEA) solution used in desulfurization process occurs frequently in the natural-gas purification plant. The foaming phenomenon has a strong impact on operation of the p... The foaming phenomenon of N-methyldiethanolamine(MDEA) solution used in desulfurization process occurs frequently in the natural-gas purification plant. The foaming phenomenon has a strong impact on operation of the process unit. The salt impurities are the main reason for causing the foaming of MDEA solution, so the full analysis of salt impurities is necessary. A method for comprehensive analysis of salt impurities in MDEA solution used in desulfurization process was established. Anions and non-metallic cations of MDEA solution were determined by different conditions of ion chromatograph, respectively. Metallic cations of the solution were detected by atomic absorption spectrophotometer with the N2O-C2H2 flame absorption. The analytical results of salt impurities in the desulfurization solution can provide a theoretical basis for an accurate analysis of the factors affecting the foaming of MDEA to unveil further control measures. 展开更多
关键词 natural-gas purification plant MDEA solution salt impurities full analysis ion chromatograph
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Detection of Total Phenols, Essential and Toxic Elements in Latvian Whole Grain Bread
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作者 Natalia Bobere Anton Podjava Ida Jakobsone 《Journal of Chemistry and Chemical Engineering》 2012年第1期1-6,共6页
A survey was carried out with the aim of assessing the level of the total phenolic compounds (TPC), essential (Na, K, Ca, Mg, Cu, Zn) and toxic (Cd and Pb) elements in 10 Latvian whole grain rye and/or wheat flo... A survey was carried out with the aim of assessing the level of the total phenolic compounds (TPC), essential (Na, K, Ca, Mg, Cu, Zn) and toxic (Cd and Pb) elements in 10 Latvian whole grain rye and/or wheat flour bread samples, obtained from the local market. The quantities of the TPC were determined by spectrophotometry. Mineral content was determined by flame photometry, flame atom absorption spectrometry (FAAS) and electrothermal atomic absorption spectrometry (ETAA) after wet digestion in concentrated HNO3. The values were comparable to the literature data. The average content in all the samples was (on a basis of weight of the product) 547 ± 28 mg/100 g for Na; 280 ±20 mg/100 g for K; 32 ± 2 mg/100 g for Ca; 88 ±5 mg/100 g for Mg; 0.49 ± 0.09 mg/100 g for Cu; 1.6 ±0.2 mg/100 g for Zn. Both Pb and Cd were determined below the limit of detection (LOD 5 0.10 mg/100 g). The LOD values were determined for each element. The TPC content in defatted samples was slightly lower than the non-defatted ones, showing the dependence on the sample preparation. The calculated average levels of the elements were compared with the maximum levels recommended or regulated by the national legislation. 展开更多
关键词 Essential and toxic elements whole grain bread flame photometry FAAS ETAA total phenols spectrophotometry.
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两种试验方法对一种阳性溶血材料的溶血性能的研究 被引量:1
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作者 赵增琳 屈秋锦 +2 位作者 侯丽 刘香东 董秀丽 《中国医疗器械信息》 2018年第3期5-7,21,共4页
目的:探讨吸光度测定法和血红蛋白浓度测定法两种不同方法对丁腈材料的溶血性能结果的影响,为有效评估医疗器械或材料的溶血性能提供合理的试验方法。方法:采用吸光度测定法和血红蛋白浓度测定法两种方法对丁腈材料进行溶血性能检测,每... 目的:探讨吸光度测定法和血红蛋白浓度测定法两种不同方法对丁腈材料的溶血性能结果的影响,为有效评估医疗器械或材料的溶血性能提供合理的试验方法。方法:采用吸光度测定法和血红蛋白浓度测定法两种方法对丁腈材料进行溶血性能检测,每种方法分别采用直接接触和间接接触两种方式进行,对测得的溶血结果进行比对。结果:直接接触血液时,两种测定方法结果没有差异(P>0.05),为轻度溶血,说明考察试验材料表面接触血液对红细胞的影响时,两种方法中对溶血性能的评价是稳定且一致的。60%浓度稀释液时,虽然结果都在同一判定标准中(都为溶血性),但吸光度测定法溶血率值明显低于血红蛋白浓度测定法(P<0.01)。100%浓度浸提液时,吸光度测定法和血红蛋白浓度测定法结果没有差异(P>0.05),均为全部溶血。结论:在实际选择溶血试验方法时,需根据医疗器械临床使用特点,选择适宜的方法考察医疗器械溶血性能。 展开更多
关键词 吸光度测定溶血法 血红蛋白浓度测定溶血法 溶血
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Noninvasive photoacoustic measurement of absorption coefficient using internal light irradiation of cylindrical diffusing fiber
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作者 彭东青 朱莉莉 +1 位作者 李志芳 李晖 《Optoelectronics Letters》 EI 2017年第5期367-371,共5页
Absorption coefficient of biological tissue is an important parameter in biomedicine, but its determination remains a challenge. In this paper, we propose a method using focusing photoacoustic imaging technique and in... Absorption coefficient of biological tissue is an important parameter in biomedicine, but its determination remains a challenge. In this paper, we propose a method using focusing photoacoustic imaging technique and internal light irradiation of cylindrical diffusing fiber(CDF) to quantify the target optical absorption coefficient. Absorption coefficients for ink absorbers are firstly determined through photoacoustic and spectrophotometric measurements at the same excitation, which demonstrates the feasibility of this method. Also, the optical absorption coefficients of ink absorbers with several concentrations are measured. Finally, the two-dimensional scanning photoacoustic image is obtained. Optical absorption coefficient measurement and simultaneous photoacoustic imaging of absorber non-invasively are the typical characteristics of the method. This method can play a significant role for non-invasive determination of blood oxygen saturation, the absorption-based imaging and therapy. 展开更多
关键词 Imaging techniques IRRADIATION Light absorption Photoacoustic effect
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