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Rapid accuracy determining DNA purity and concentration in heavy oils by spectrophotometry methods
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作者 YunYang Wan HongMei Mu +4 位作者 Na Luo JianPing Yang Yan Tian Ning Hong HaiLiang Dong 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3394-3399,共6页
DNA analysis is the core of biotechnology applied in petroleum resources and engineering. Traditionally accurate determination of DNA purity and concentration by spectrometer is the first and critical step for downstr... DNA analysis is the core of biotechnology applied in petroleum resources and engineering. Traditionally accurate determination of DNA purity and concentration by spectrometer is the first and critical step for downstream molecular biology research. In this study, three different spectrophotometry methods, BPM, NDTT and NPMTTZ were compared for their performance in determining DNA concentration and purity in 32 oil samples, and molecule methods like quantitative real-time PCR (qPCR) and high-throughput sequence were also performed to help assess the accuracy of the three methods in determining DNA concentration and purity. For ordinary heavy oil (OHO), extra heavy oil (EHO) and super heavy oil (SHO), the characteristics of high viscosity (η), density (ρ) and resin plus asphaltene content will affect the DNA extraction and UV determination. The DNA concentration was decreased as density increased: OHO (11.46 ± 18.34 ng/μL), EHO (6.68 ± 9.67 ng/μL) and SHO (6.20 ± 7.83 ng/μL), and the DNA purity was on the reverse: OHO (1.31 ± 0.27), EHO (1.54 ± 0.20), and SHO (1.83 ± 0.32). The results suggest that spectrophotometry such as BPM and NPMTTZ are qualitatively favorite methods as the quick non-consumable methods in determining DNA concentration and purity of medium oil and heavy oil. 展开更多
关键词 Heavy oil DNA concentration DNA purity spectrophotometry qPCR
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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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Serum paraquat concentration detected by spectrophotometry in patients with paraquat poisoning 被引量:6
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作者 Chang-bin Li Xin-hua Li +2 位作者 Zhen Wang Cheng-hua Jiang Ai Peng 《World Journal of Emergency Medicine》 SCIE CAS 2011年第3期179-184,共6页
BACKGROUND:Paraquat (PQ) is a world-wide used herbicide and also a type of common poison for suicide and accidental poisoning. Numerous studies have proved that the concentration of serum PQ plays an important role... BACKGROUND:Paraquat (PQ) is a world-wide used herbicide and also a type of common poison for suicide and accidental poisoning. Numerous studies have proved that the concentration of serum PQ plays an important role in prognosis. Spectrophotometry, including common spectrophotometry and second-derivative spectrophotometry, is commonly used for PQ detection in primary hospitals. So far, lack of systematic research on the reliability of the method and the correlation between clinical features of patients with PQ poisoning and the test results has restricted the clinical use of spectrophotometry. This study aimed to evaluate the reliability and value of spectrophotometry in detecting the concentration of serum PQ. METHODS:The wavelengths for detecting the concentration of serum PQ by common and second-derivative spectrophotometry were determined. Second-derivative spectrophotometry was applied to detect the concentration of serum PQ. The linear range and precision for detection of PQ concentration by this method were confirmed. The concentration of serum PQ shown by second- derivative spectrophotometry and HPLC were compared in 8 patients with PQ poisoning. Altogether 21 patients with acute poisoning 4 hours after PQ ingestion treated in the period of October 2008 to September 2010 were retrospectively reviewed. The patients were divided into higher and lower than 1.8 μg/mL groups based on their concentrations of serum PQ measured by second-derivative spectrophotometry on admission. The severity of clinical manifestations between the two groups were analyzed with Student's t test or Fisher's exact test. RESULTS:The absorption peak of 257 nm could not be found when common spectrophotometry was used to detect the PQ concentration in serum. The calibration curve in the 0.4-8.0 μg/mL range for PQ concentration shown by second-derivative spectrophotometry obeyed Beer's law with r=0.996. The average recovery rates of PQ were within a range of 95.0% to 99.5%, relative standard deviation (RSD) was within 1.35% to 5.41% (n=6), and the lower detection limit was 0.05 μg/mL. The PQ concentrations in serum of 8 patients with PQ poisoning shown by second-derivative spectrophotometry were consistent with the quantitative determinations by HPLC (r=0.995, P〈0.0001). The survival rate was 22.2% in patients whose PQ concentration in serum was more than 1.8 μg/mL, and the incidences of acidosis, oliguria and pneumomediastinum in these patients were 55.6%, 55.6% and 77.8%, respectively. These clinical manifestations were different significantly from those of the patients whose PQ concentration in serum was less than 1.8 pg/mL (P〈0.05). CONCLUSIONS: For common spectrophotometry, the wavelength at 257 nm was not suitable for detecting serum PQ as no absorbance was shown. Second-derivative spectrophotometry was reliable for detecting serum paraquat concentration. Serum PQ concentration detected by second- derivative spectrophotometry could be used to predict the severity of clinical manifestations of patients with PQ poisoning, and PQ content higher than 1.8 tJg/mL 4 hours after ingestion could be an important predictive factor for poor prognosis. 展开更多
关键词 spectrophotometry Derivative spectrophotometry PARAQUAT POISONING SERUM Concentration
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Estimation of the galanthamine using derivative spectrophotometry in bulk drug and formulation 被引量:1
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作者 Karan Mittal Ramni Kaushal +1 位作者 Rajashree Mashru Arti Thakkar 《Journal of Biomedical Science and Engineering》 2010年第4期439-441,共3页
Two simple, rapid, accurate, precise, reliable and economical spectrophotometric methods have been proposed for the determination of galanthamine hydrobromide (GH) in bulk and pharmaceutical formulation. First method ... Two simple, rapid, accurate, precise, reliable and economical spectrophotometric methods have been proposed for the determination of galanthamine hydrobromide (GH) in bulk and pharmaceutical formulation. First method is zero order UV spectrophotometry and second is 1st derivative zero crossing spectrophotometry. The developed methods have shown best results in terms of linearity, accuracy, precision, LOD and LOQ for bulk drugs and marketed formulations. Absorbance was measured at 287 nm for zero order and 277.4 nm for first derivative. It obeyed Lambert-Beer’s law in the range of 30-80 μg mL-1. Both methods have good linearity (r2 = 0.9997) and accuracy found to be 100.5% and 101.2% for both methods respectively. 展开更多
关键词 alanthamine Hydrobromide (GH) ZERO Order UV-spectrophotometry First Derivative ZERO CROSSING spectrophotometry
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Determination of Total Flavones Content in Ceratocarpus arenarius L. by Spectrophotometry
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作者 刘珊珊 马先梅 杨红兵 《Agricultural Science & Technology》 CAS 2011年第11期1612-1614,共3页
[Objective] The aim was to establish the method for determining total flavoens content in Ceratocarpus arenarius L.[Method ] Flavonoids were extracted from C. arenarius by heating refluxing, and determined with rutin ... [Objective] The aim was to establish the method for determining total flavoens content in Ceratocarpus arenarius L.[Method ] Flavonoids were extracted from C. arenarius by heating refluxing, and determined with rutin as the standard.[Result] In the range of 0.019-0.102 mg/ml, linear relationship was good (r=0.999 1). This method had higher precision and accuracy with RSD of 0.226% and recoveries of 99.36%. The total flavones content from C. arenarius was 10.12 mg/g. [Conclusion] The method is simple and reliable, which could be used to control the quality of C. arenariu. 展开更多
关键词 Ceratocarpus arenarius L. FLAVONOIDS spectrophotometry
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Studies on the Combined Derivative Spectrophotometry
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作者 Shi Huiming, Xi Changsheng, Li Jinhe and Ren Hongji (Department of Chemistry, Nankai University, Tianjin) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1989年第3期244-249,共6页
The combined derivative spectrophotometry developed in this paper is a new method, which can be used to determine multicomporent mixture simultaneously and may improve the sensitivity and accuracy of the measurement r... The combined derivative spectrophotometry developed in this paper is a new method, which can be used to determine multicomporent mixture simultaneously and may improve the sensitivity and accuracy of the measurement remarkably. Two practical tests were carried out to verify the correctness of the theory, and the results are satisfactory. 展开更多
关键词 Combined derivative spectrophotometry Derivative spectrophotometry GERMANIUM TUNGSTEN MOLYBDENUM
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Quantitative Determination of Benoxinate Hydrochloride by Three Wavelength Spectrophotometry 被引量:9
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作者 HUI Rui-hua HOU Dong-yan and HUI Yu-lin(The Centre of Analysis and Measurenient,Liaoning University,Shenyang, 110036) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1994年第4期297-300,共4页
hree wavelength spectrophotometry was used to determine the content ofbenoxinate hydrochloride.Using this method could effectively eliminate the devia-tion of background absorption caused by the change of concentratio... hree wavelength spectrophotometry was used to determine the content ofbenoxinate hydrochloride.Using this method could effectively eliminate the devia-tion of background absorption caused by the change of concentration and the errorof quantitative anaiysis caused by asymmetric peaks, and at the same time the lean-ing degree of base line was corrected.This method was simple, the recovery was98. 62% 101. 86% and the coefficient of variation was 0. 551%. 展开更多
关键词 spectrophotometry Three wavelength Benoxinate hydrochloride
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Rapid measurement of indocyanine green retention by pulse spectrophotometry: a validation study in 70 patients with Child-Pugh A cirrhosis before hepatectomy for hepatocellular carcinoma 被引量:8
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作者 Tan To Cheung See Ching Chan +5 位作者 Kenneth SH Chok Albert CY Chan Wan Ching Yu Ronnie TP Poon Chung Mau Lo Sheung Tat Fan 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2012年第3期267-271,共5页
BACKGROUND: The indocyanine green (ICG) retention test is the most popular liver function test for selecting patients for major hepatectomy. Traditionally, it is done using spectrophotometry with serial blood sampling... BACKGROUND: The indocyanine green (ICG) retention test is the most popular liver function test for selecting patients for major hepatectomy. Traditionally, it is done using spectrophotometry with serial blood sampling. The newly- developed pulse spectrophotometry is a faster alternative, but its accuracy on Child-Pugh A cirrhotic patients undergoing hepatectomy for hepatocellular carcinoma has not been well documented. This study aimed to assess the accuracy of the LiMON , one of the pulse spectrophotometry systems, in measuring preoperative ICG retention in these patients and to devise an easy formula for conversion of the results so that they can be compared with classical literature records where ICG retention was measured by the traditional method. METHODS: We measured the liver function of 70 Child-Pugh A cirrhotic patients before hepatectomy for hepatocellular carcinoma from September 2008 to January 2009. ICG retention at 15 minutes measured by traditional spectrophotometry (ICGR15) was compared with ICG retention at 15 minutes measured by the LiMON (ICGR15(L)). RESULTS: The median ICGR15 was 14.7% (5.6%-32%) and the median ICGR15(L) was 10.4% (1.2%-28%). The mean difference between them was -4.3606. There was a strong correlation between ICGR15 and ICGR15(L) (correlation coefficient, 0.844; 95% confidence interval, 0.762-0.899). The following formula was devised: ICGR15=1.16×ICGR15(L)+2.73.CONCLUSIONS: The LiMON provides a fast and repeatable way to measure ICG retention at 15 minutes, but with constant underestimation of the real value. Therefore, when comparing results obtained by traditional spectrophotometry and the LiMON, adjustment of results from the latter is necessary, and this can be done with a simple mathematical calculation using the above formula. 展开更多
关键词 Child-Pugh A liver cirrhosis hepatocellular carcinoma indocyanine green clearance LiMON pulse spectrophotometry
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Quantitative analysis of cefixime via complexation with palladium(Ⅱ) in pharmaceutical formulations by spectrophotometry 被引量:3
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作者 Syed Najmul Hejaz Azmi Bashir Iqbal +3 位作者 Nada Said Hassan Al-Humaimi Iman Rashid Saif Al-Salmani Noora Ali Saad Al-Ghafri Nafisur Rahman 《Journal of Pharmaceutical Analysis》 SCIE CAS 2013年第4期248-256,共9页
An optimized and validated spectrophotometric method has been developed for the determination of cefixime in pharmaceutical formulations. The method is based on the complexa- tion reaction between cefixime and palladi... An optimized and validated spectrophotometric method has been developed for the determination of cefixime in pharmaceutical formulations. The method is based on the complexa- tion reaction between cefixime and palladium ion in the presence of acidic buffer solution (pH 3) in ethanol-distilled water medium at room temperature. The complex absorbed maximally at 352 nm. Beer's law is obeyed in the working concentration range of 2.5-35 μg/mL with apparent molar absorptivity of 1.015×104 L/mol cm and Sandell's sensitivity of 0.001 μg/cm2/0.001 absorbance unit. The limits of detection and quantitation for the proposed method are 0.175 and 0.583μg/mL, respectively. The effect of common excipients used as additives has been studied in the determination of cefixime. The proposed method has been successfully applied for the determina- tion of cefixime in pharmaceutical formulations. The results obtained by the proposed method were statistically compared with the reference method using t and F values and found no significant difference between the two methods. 展开更多
关键词 spectrophotometry CEFIXIME Palladium ion Pd(II)-cefixime complex
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Application of derivative ratio spectrophotometry for determination of β-carotene and astaxanthin from Phaffia rhodozyma extract 被引量:5
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作者 倪辉 何国庆 +2 位作者 阮晖 陈启和 陈锋 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第6期514-522,共9页
A derivative ratio spectrophotometric method was used for the simultaneous determination of β-carotene and astaxanthin produced from Phaffia rhodozyma. Absorbencies of a series of the standard carotenoids in the rang... A derivative ratio spectrophotometric method was used for the simultaneous determination of β-carotene and astaxanthin produced from Phaffia rhodozyma. Absorbencies of a series of the standard carotenoids in the range of 441 nm to 490 nm demonstrated that their absorptive spectra accorded with Beer’s law and that the additivity when the concentrations of β-carotene and astaxanthin and their mixture were within the range of 0 to 5 μg/ml, 0 to 6 μg/ml, and 0 to 6 μg/ml, respectively. When the wavelength interval (?λ) at 2 nm was selected to calculate the first derivative ratio spectra values, the first derivative amplitudes at 461 nm and 466 nm were suitable for quantitatively determining β-carotene and astaxanthin, respectively. Effect of divisor on derivative ratio spectra could be neglected; any concentration used as divisor in range of 1.0 to 4.0 μg/ml is ideal for calculating the derivative ratio spectra values of the two carotenoids. Calibration graphs were established for β-carotene within 0?6.0 μg/ml and for astaxanthin within 0?5.0 μg/ml with their corresponding regressive equations in: y=?0.0082x?0.0002 and y=0.0146x?0.0006, respectively. R-square values in excess of 0.999 indicated the good linearity of the calibration graphs. Sample recovery rates were found satisfactory (>99%) with relative standard deviations (RSD) of less than 5%. This method was suc- cessfully applied to simultaneous determination of β-carotene and astaxanthin in the laboratory-prepared mixtures and the extract from the Phaffia rhodozyma culture. 展开更多
关键词 Derivative ratio spectrum Β-CAROTENE ASTAXANTHIN spectrophotometry
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Determination of Mecruy at Trace Level in Natural Water Samples by Hydride Generation Atomic Absorption Spectrophotometry after Cloud Point Extraction Preconcentration 被引量:2
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作者 Ji Ying SONG Ming HOU Li Xiang ZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第9期1217-1220,共4页
A method for the determination of trace mercury in water samples by hydride generation atomic absorption spectrophotometry after cloud point extraction was proposed in the present work. The effects of pH, concentratio... A method for the determination of trace mercury in water samples by hydride generation atomic absorption spectrophotometry after cloud point extraction was proposed in the present work. The effects of pH, concentration of surfactant, and equilibration time on cloud point extraction were discussed. The enhancement factor of 20 and the detection limit of 0.039 μg/L were obtained for mercury with relative standard deviation of 4.8% (n = 11). 展开更多
关键词 Cloud point extraction MERCURY hydride generation atomic absorption spectrophotometry.
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Catalytic Spectrophotometry for Vanadium Determination Based on Oxidation of Arsenazo Ⅲ by Bichromate 被引量:1
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作者 何荣桓 王建华 《Rare Metals》 SCIE EI CAS CSCD 1999年第2期18-22,共5页
A catalytic spectrophotometry for the determination of trace amount of vanadium was developed based on its catalytic effect on the oxidation of arsenazo by potassium bichromate in weak acidic medium. The optimized co... A catalytic spectrophotometry for the determination of trace amount of vanadium was developed based on its catalytic effect on the oxidation of arsenazo by potassium bichromate in weak acidic medium. The optimized conditions for determinations are: cK2Cr2O7=3.010-5 molL-1, carsenazo =3.010-5 molL-1, pH=4.0, t=90. The calibration graph is linear for 0.020.2 gml-1, and the detection limit is 0.02 gml-1 V. The apparent active energy of this catalytic reaction is 21.72 kJmol-1. Most foreign ions do not interfere with the determination of vadadium, except for Fe() and Co(), and their interferences could be eliminated by ion exchange. The present method has been used to make the determination of vanadium in human hair, tea, potato and wastewater, and the results were satisfactory. 展开更多
关键词 Kinetic spectrophotometry ARSENAZO Bichromate VANADIUM DETERMINATION
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Analysis of Peanut Oil Adulterated with Other Edible Oils by Spectrophotometry 被引量:1
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作者 SU Rui1, WANG Xing-hua1, ZHAO Tian-qi1, YU Wen-zhi1, FENG Xu-dong1, ZHANG Han-qi1 and YU Ai-min1,2 1. College of Chemistry, Jilin University, Changchun 130012, P. R. China 2. Changchun Jilin University Little Swan Instrument Co., Ltd., Changchun 130012, P. R. China 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第1期14-18,共5页
Since peanut oil(PO) is more expensive than other seed oils, some PO is adulterated with other cheap seed oils, such as soybean oil, palm olein, cottonseed oil, corn oil and rapeseed oil. The conventional method for... Since peanut oil(PO) is more expensive than other seed oils, some PO is adulterated with other cheap seed oils, such as soybean oil, palm olein, cottonseed oil, corn oil and rapeseed oil. The conventional method for deter mining whether PO was adulterated is to detect the freezing point of oils. The proposed method for the determination of adulterants in PO was based on monitoring the change of absorbance when the sample was refrigerated. A special spectrophotometer was developed. A total of 10 kinds of POs from different suppliers were chosen and adulterated with other seed oils at the volume fraction levels ranging from 5% to 30%. A total of 150 samples were analyzed by the proposed method and the results were satisfactory. 展开更多
关键词 Peanut oil ADULTERATION spectrophotometry Direct analysis
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The Simultaneous Determination of Five Components Including Acetaminophen by Ridge Regression Spectrophotometry 被引量:1
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作者 张立庆 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2001年第2期79-82,共4页
Ridge regression spectrophotometry(LHG)is used for thesimultaneous determination of five components(acetaminophen,p-aminophenol, caffeine, chlorphenamine maleate and guaifenesin)incough syr- up. The computer program o... Ridge regression spectrophotometry(LHG)is used for thesimultaneous determination of five components(acetaminophen,p-aminophenol, caffeine, chlorphenamine maleate and guaifenesin)incough syr- up. The computer program of LHG is based on VB language.The difficulties in overlapping of absorption spectrums of fivecompounds are overcome by this procedure. The experimental resultsshow that the recovery of each component is in the range from97.9/100 to 103.3/100 and each component obtains satisfactory resultswithout any pre-separation. 展开更多
关键词 ACETAMINOPHEN ridge regression spectrophotometry five-components
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Dual-wavelength dual-indicator catalytic kinetic spectrophotometry for determination of trace Ru(Ⅲ) 被引量:1
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作者 Hai-Yan Chen Yu-Jing Chen Ming Zhang 《Rare Metals》 SCIE EI CAS CSCD 2013年第6期605-608,共4页
A new dual-wavelength dual-indicator catalytic kinetic spectrophotometric method for the determination of trace Ru(III)was studied.This method was based on Ru(III)-catalyzing oxidation of Arsenazo I and indigo carmine... A new dual-wavelength dual-indicator catalytic kinetic spectrophotometric method for the determination of trace Ru(III)was studied.This method was based on Ru(III)-catalyzing oxidation of Arsenazo I and indigo carmine by potassium bromate in sulfuric acid.The absorbances of the catalytic and noncatalytic systems were measured at 510 and610 nm,respectively.Under the optimum conditions,the linear range of determination is 0–0.12 lgáml-1and the detection limit is 1.21 9 10-4lgáml-1.The method was applied for the determination of trace Ru(III)in ore samples with satisfactory results. 展开更多
关键词 DUAL-WAVELENGTH Catalytic spectrophotometry Ru(III) Arsenazo I Indigo carmine
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Determination of Trace Amount of Yttrium with Bromopyrogallol Red by solid-phase Spectrophotometry 被引量:1
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作者 Jinzhang Gao,Gang Ni, Li Yuan, Jingwan Kang Department of Chemistry, Northwest Normal University, Lanzhou 730070, China 《Rare Metals》 SCIE EI CAS CSCD 2001年第3期202-204,共3页
A simple and sensitive method for the determination of trace amount of yttrium by solid-phase spectrophotometry has been studied. Yttrium can form a 1 : 1 complex with bromopyrogallol red (BPR) on resin, which was det... A simple and sensitive method for the determination of trace amount of yttrium by solid-phase spectrophotometry has been studied. Yttrium can form a 1 : 1 complex with bromopyrogallol red (BPR) on resin, which was determined directly at 605 nm, pH=6.5. It has a highly sensitivity (epsilon = 6.3 x 10(6)) which is 300-fold higher than the corresponding spectrophotometry in solution. The method was applied to the determination of yttrium in churchite. 展开更多
关键词 solid-phase spectrophotometry bromopyrogallol red (BPR) YTTRIUM
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Spectrophotometric Determination of Water-Soluble Hexavalent Chromium and Determination of Total Hexavalent Chromium Content of Portland Cement in the Presence of Iron (III) and Titanium (IV) Using Derivative Ratio Spectrophotometry 被引量:1
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作者 K. A. Idriss H. Sedaira S. Dardeery 《American Journal of Analytical Chemistry》 2013年第11期653-660,共8页
A rapid, reliable and accurate method for the determination of hexavalent chromium in Portland cement is developed. The proposed method includes direct spectrophotometric determination of Cr (VI) in Portland cement wi... A rapid, reliable and accurate method for the determination of hexavalent chromium in Portland cement is developed. The proposed method includes direct spectrophotometric determination of Cr (VI) in Portland cement with 1, 2, 5, 8 Tetrahydroxyanthraquinone, (Quinalizarin, QINZ) at pH 1.5. The European Directive (2003/53/EC) limits the use of cements so that it contains no more than 2 mg.Kg-1 of water-soluble Cr (VI). The absorbance at 565 nm due to Cr (VI)-QINZ complex is recommended for the determination of water-soluble Cr (VI) in Portland cement. The quantification of Cr (VI) released from cement when mixed with water is performed according to TRGS 613 (Technical Rules of Hazardous Substances). The validity of the method is thoroughly examined and the proposed method gives satisfactory results. A derivative spectrophotometric method has been developed for the determination of total Cr (VI) in Portland cement in the presence of Fe (III) and Ti (IV). The hexavalent chromium complex formed at pH 1.5 allows precise and accurate determination of chromium (VI) over the concentration range 0.05 to 3.0 mg.L-1of chromium (VI). The validity of the method was examined by analyzing several Standard Reference Material (SRM) Portland cement samples. The MDL (at 95% confidence level) was found to be 25 ng/mL for chromium (VI) in National Institute of Standards and Technology (NIST) cement samples using the proposed method. 展开更多
关键词 CHROMIUM (VI) DETERMINATION Quinalizarin Portland Cement Analysis DERIVATIVE spectrophotometry
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Separation/Enrichment of Copper and Silver Using Titanium Dioxide Nanoparticles Coated with Poly-Thiophene and Their Analysis by Flame Atomic Absorption Spectrophotometry 被引量:1
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作者 Mohammad Behbahani Meysam Babapour +4 位作者 Mostafa M. Amini Omid Sadeghi Akbar Bagheri Mani Salarian Banafsheh Rafiee 《American Journal of Analytical Chemistry》 2013年第2期90-98,共9页
We report on the use of titanium dioxide nanoparticles (NPs) coated with poly-thiophene for the preconcentration of copper and silverions. The NPs were prepared by first modifying the surface of TiO2 NPs with vinyl gr... We report on the use of titanium dioxide nanoparticles (NPs) coated with poly-thiophene for the preconcentration of copper and silverions. The NPs were prepared by first modifying the surface of TiO2 NPs with vinyl groups and then copolymerizing them with vinyl thiophen. The resulting TiO2-polythiophene core-shell NPs were characterized by thermogravimetry, differential thermal analysis, scanning electron microscopy, Fourier transform infrared spectrometry and X-ray diffraction. The experimental conditions such as pH value, adsorption and desorption time, type, concentration and volume of the eluent, break through volume, and effect of potentially interfering ions were optimized. The ions were then desorbed with hydrochloric acid and determined by FAAS. The limits of detection are 0.4 and 1.2 μg·L_1 for Cu(II) and Ag(I), respectively, and recoveries and precisions are >98.0% 展开更多
关键词 Novel Poly-Thiophene-TiO2 Nanoparticles COPPER SILVER Flame Atomic Absorption spectrophotometry
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Concentration determination of gold nanoparticles by flame atomic absorption spectrophotometry 被引量:1
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作者 Yuhong Fu Quan Wan +4 位作者 Zonghua Qin Shanshan Li Sen Li Ji Wang Wei Zhang 《Acta Geochimica》 EI CAS CSCD 2021年第4期498-506,共9页
While engineered nanoparticles are widely used and maybe eventually released into the environment,natural nanoparticles are also commonly found in the Earth system.Nanoparticles may critically affect the geochemical m... While engineered nanoparticles are widely used and maybe eventually released into the environment,natural nanoparticles are also commonly found in the Earth system.Nanoparticles may critically affect the geochemical migration of associated elements and pose potential threats to the ecological environment.It is necessary to establish an accurate and reliable method for measuring the concentration of nanoparticles.AAS is one of the most commonly used methods for the concentration determination of nanoparticles.However,till now,there has been no systematic report on how experimental variables affect AAS measurements.In this study,we used gold nanoparticles(AuNPs) as an example and studied the influences of a list of factors on the concentration determination of AuNPs by AAS,including digestion method,ionization interference,acidic medium,background correction method,and organic matter.We demonstrate that all these factors may have varying degrees of influence on the measured gold concentrations.When the gold colloid is digested at room temperature for more than 8 h or at 60℃ for more than 2 h,and the system contains a low concentration of organic matter,AAS can accurately measure the AuNP concentration at ppm-level.The deuterium lamp background deduction method is not recommended to use for samples with lower gold concentrations. 展开更多
关键词 Gold nanoparticles Atomic absorption spectrophotometry Quantitative analysis Organic matter
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Simultaneous Determination of Zirconium and Hafnium by Dual System and Dual Wavelength Spectrophotometry
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作者 张贵珠 刘蜀利 +2 位作者 杨万龙 何锡文 史慧明 《Rare Metals》 SCIE EI CAS CSCD 1993年第4期301-304,共4页
A dual system and dual wavelength spectrophotometry (DSDWS) used to simultaneously determine Zr and Hf were proposed. Zr(Hf)-XO-CIMAB and Zr(Hf)-CAB-CDMAA-Triton X-100 were chosen as a pair of chromophoric systems. Th... A dual system and dual wavelength spectrophotometry (DSDWS) used to simultaneously determine Zr and Hf were proposed. Zr(Hf)-XO-CIMAB and Zr(Hf)-CAB-CDMAA-Triton X-100 were chosen as a pair of chromophoric systems. The difference of chromophoric behaviours between Zr and Hf is increased by the addition of hydrogen peroxide as masking agent and by adjustment of acidity. The apparent molar absorptivities of Zr and Hf are 2.0×105 and 5.0×104 L&middotmol-1&middotcm-1 respectively. The procedure is simple and rapid. 展开更多
关键词 HAFNIUM MEASUREMENTS spectrophotometry Wave propagation Wavemeters
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