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Effects of Standing Time during Pretreatment on the Nitrite Concentration Detected by Spectrophotometric Method
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作者 Yingfei Zeng Juan Hu +2 位作者 Xianglong Bian Qianfeng Xia Tingwei Hu 《Journal of Materials Science and Chemical Engineering》 2024年第2期73-83,共11页
Food safety problems caused by excessive nitrite addition have been frequently reported and the detection of nitrite in food is particularly important. The standing time during the pretreatment of primary sample has a... Food safety problems caused by excessive nitrite addition have been frequently reported and the detection of nitrite in food is particularly important. The standing time during the pretreatment of primary sample has a great influence on the concentration of nitrite tested by spectrophotometric method. In this context, three kinds of food samples are prepared, including canned mustard, canned fish and home-made pickled water. A series of standing times are placed during the sample pretreatments and the corresponding nitrite contents in these samples are detected by spectrophotometric method based on N-ethylenediamine dihydrochloride. This study aims to find out a reasonable standing time during the pretreatment of food sample, providing influence factor for precise detection of nitrite. 展开更多
关键词 Standing Time spectrophotometric Method Nitrite Detection
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Catalytic spectrophotometric determination of trace selenium in microemulsion after separation and enrichment by SDG 被引量:6
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作者 LI Huizhi ZHAI Diantang FAN Yingju 《Rare Metals》 SCIE EI CAS CSCD 2006年第3期281-286,共6页
A new catalytic spectrophotometric method was developed for the determination of trace amount of Se(Ⅳ) in microemulsion medium. The method is based on the catalytic effect of traces of Se(Ⅳ) on the oxidation of ... A new catalytic spectrophotometric method was developed for the determination of trace amount of Se(Ⅳ) in microemulsion medium. The method is based on the catalytic effect of traces of Se(Ⅳ) on the oxidation of 2',4'-dichlorophenylfluomne (p-CPF) by potassium bromate with HNO3 as an activator in the presence of nonionic microemulsion medium. Under optimum conditions, the calibration graph is linear in the range of 0.4-15 μg·L^-1 of Se(Ⅳ) at 480 nm. The detection limit achieved is 9.86 × 10^-10μg·L^-1. Samples were dissolved and the obtained trace Se(Ⅳ) was separated and enriched by sulphydryl dextrane gel (SDG). The method has been applied for determination of trace selenium with satisfactory results. 展开更多
关键词 analytical chemistry Se(Ⅳ) catalytic spectrophotometric microemulsion medium SEPARATION ENRICHMENT
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A New Spectrophotometric Method for Measuring COD of Seawater 被引量:4
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作者 LIU Ying JI Hongwei XIN Huizhen LIU Li 《Journal of Ocean University of China》 SCIE CAS 2006年第2期137-140,共4页
This research studied a new spectrophotometric method for measuring the chemical oxygen demand (COD) of seawater. In this method, the COD was measured using a spectrophotometer instead of titrating with sodium thios... This research studied a new spectrophotometric method for measuring the chemical oxygen demand (COD) of seawater. In this method, the COD was measured using a spectrophotometer instead of titrating with sodium thiosuiphate. The measuring wavelength was selected to be 470 nm, and the COD of three standard glucose solutions (COD = 0.5, 1.5 and 2.5 mgL^-1, respectively) and two seawater samples (from the South Yellow Sea and Jiaozhou Bay) were measured using the spectrophotometric method and titrimetric method respectively. The results showed that the spectrophotometric method was somewhat better than the titrimetric method. The relative standard deviation (RSD) of the spectrophotometric method was less than 2.7%, and the recovery of seawater samples ranged from 96.3% to 103.8%. In addition, the spectrophotometric method has other advantages such as expeditiousness, operation simplicity, analysis automatization, etc. Therefore the spectrophotometric method can be used to measure the COD of seawater with satisfactory results. 展开更多
关键词 chemical oxygen demand (COD) spectrophotometric method seawater
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Simultaneous Determination of Iron and Manganese in Water Using Artificial Neural Network Catalytic Spectrophotometric Method 被引量:4
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作者 JI Hongwei XU Yan +2 位作者 LI Shuang XIN Huizhen CAO Hengxia 《Journal of Ocean University of China》 SCIE CAS 2012年第3期323-330,共8页
A new analytical method using Back-Propagation (BP) artificial neural network and kinetic spectrophotometry for simultaneous determination of iron and magnesium in tap water, the Yellow River water and seawater is est... A new analytical method using Back-Propagation (BP) artificial neural network and kinetic spectrophotometry for simultaneous determination of iron and magnesium in tap water, the Yellow River water and seawater is established. By conditional experiments, the optimum analytical conditions and parameters are obtained. Levenberg-Marquart (L-M) algorithm is used for calculation in BP neural network. The topological structure of three-layer BP ANN network architecture is chosen as 15-16-2 (nodes). The initial value of gradient coefficient μ is fixed at 0.001 and the increase factor and reduction factor of μ take the default values of the system. The data are processed by computers with our own programs written in MATLAB 7.0. The relative standard deviation of the calculated results for iron and manganese is 2.30% and 2.67% respectively. The results of standard addition method show that for the tap water, the recoveries of iron and manganese are in the ranges of 98.0%-104.3% and 96.5%-104.5%, and the RSD is in the range of 0.23%-0.98%; for the Yellow River water (Lijin district of Shandong Province), the recoveries of iron and manganese are in the ranges of 96.0%-101.0% and 98.7%-104.2%, and the RSD is in the range of 0.13%-2.52%; for the seawater in Qingdao offshore, the recoveries of iron and manganese are in the ranges of 95.3%-104.8% and 95.3%-104.7%, and the RSD is in the range of 0.14%-2.66%. It is found that 21 common cations and anions do not interfere with the determination of iron and manganese under the optimum experimental conditions. This method exhibits good reproducibility and high accuracy in the determination of iron and manganese and can be used for the simultaneous determination of iron and manganese in tap water and natural water. By using the established ANN- catalytic spectrophotometric method, the iron and manganese concentrations of the surface seawater at 11 sites in Qingdao offshore are determined and the level distribution maps of iron and manganese are drawn. 展开更多
关键词 artificial neural network simultaneous determination kinetic spectrophotometric method iron MANGANESE
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Solid-phase extraction of trace Au(Ⅲ) with SDG and determination by the catalytic spectrophotometric method 被引量:2
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作者 LI Huizhi ZHAI Yubo 《Rare Metals》 SCIE EI CAS CSCD 2008年第6期560-565,共6页
The new catalytic kinetic spectrophotometric method for Au(III) determination was developed and validated. It was based on the catalytic effect of gold on the oxidation of sudan red III by ammonium peroxodisulfate ... The new catalytic kinetic spectrophotometric method for Au(III) determination was developed and validated. It was based on the catalytic effect of gold on the oxidation of sudan red III by ammonium peroxodisulfate ((NH4)2S2O8) with nitrilo triacetic acid as an activator in microemulsion and H2SO4 medium. Under optimum conditions, there was the linearity of the calibration curve in the concentration range from 0 to 20 μg/L Au(Ⅲ) at 520 nm. The relative standard deviation was 3.0% with a correlation coefficient of 0.9986. The detection limit achieved was 9.75 × 10^-5 μg/mL. A new method using a column packed with sulfhydryl dextrose gel (SDG) as a solid-phase extractant has been developed for the preconcentration and separation of Au(Ⅲ) ions. The method has been applied to the determination of trace gold with satisfactory results. 展开更多
关键词 analytical chemistry catalytic kinetic spectrophotometric method solid-phase extraction gold(Ⅲ)
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Indirect Spectrophotometric Determination of Sulphide with the Complex of Cd(Ⅱ)-5-Br-PADAP-CPB 被引量:1
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作者 Zhen Yu Zhang Wei An Liang(Department of Chemistry, Shandong University, Jinan 250100) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第11期983-984,共2页
By the use of CPB, Cd(Ⅲ) forms a highly sensitive complex with 5-Br-PADAP in aqueous solution, molar absorptivity εis 1. 21 ×105 1. mol-1. cm-1.Trace amount of sulphide can be determined from its effect on the... By the use of CPB, Cd(Ⅲ) forms a highly sensitive complex with 5-Br-PADAP in aqueous solution, molar absorptivity εis 1. 21 ×105 1. mol-1. cm-1.Trace amount of sulphide can be determined from its effect on the complex of Cd (Ⅲ)-5-Br-PADAP-CPB, sulphide in the range 0~3. 2 ×10-6mol dm-3 causes a decrease in absorption, that is a linear function of the concentration, For 13ng cm-3 sulphide, common metal ions such as Na+, K+, Ca2+, Mg2+, Al3+ and anions such as CO (24μg cm-3). S2O (22μg cm-3). PO (20μg cm-3) etc. do not interfere. A method for the indirect determination of sulphide in beer and in dustrial waste water with good selectivity and accuracy is described. 展开更多
关键词 CPB Br-PADAP-CPB Indirect spectrophotometric Determination of Sulphide with the Complex of Cd
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Spectrophotometric Determination of Fluoride in Groundwater Using Resorcin Blue Complexes 被引量:1
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作者 Zaher Barghouthi Sameer Amereih 《American Journal of Analytical Chemistry》 2012年第9期651-655,共5页
New simple and sensitive spectrophotometric determination of fluoride in drinking groundwater has been developed using aluminium-resorcin blue complex. The method is based on the reaction of fluoride with the coloured... New simple and sensitive spectrophotometric determination of fluoride in drinking groundwater has been developed using aluminium-resorcin blue complex. The method is based on the reaction of fluoride with the coloured complex to produce colourless aluminium fluoride complex and releasing of the free ligand. The relationship of the reaction of flu-oride with the complex is sixth-order polynomial function. The reaction reaches equilibrium at fluoride concentration of 0.054 mM. The equilibrium constant (Keq) was calculated as 1.12 × 1014. Beer-Lambert law is obeyed in the range 0.0 - 0.024 mM of fluoride (0.0 - 1.0 mg·L-1). The molar absorptivity at 502 nm is 6.45 × 103 L·mol-1·cm-1. Fluoride concentration higher than 1.0 mg·L-1 can be measured after proper dilution. The sensitivity, detection limit, quantitation limit, and the percentage recovery of 0.75 mg·L-1 fluoride for the method were found to be 0.357 μg·ml-1., 0.07 mg·L-1, 0.2 mg·L-1, and 101.1 respectively. 展开更多
关键词 FLUORIDE GROUNDWATER spectrophotometric Method Aluminium Resorcin BLUE COMPLEX
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Application of Total Error Strategy in Validation of Affordable and Accessible UV-Visible Spectrophotometric Methods for Quality Control of Poor Medicines 被引量:1
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作者 Jérémie Kindenge Mbinze Jean Nsangu Mpasi +8 位作者 Elza Maghe Sébastien Kobo Rodrigue Mwanda Guy Mulumba Jacquie Bolavie Bolande Trésor Menanzambi Bayebila Maguy Borive Amani Philippe Hubert Roland Djang’eing’a Marini 《American Journal of Analytical Chemistry》 2015年第2期106-117,共12页
In the framework of fighting against the poor quality medicines sold in developing countries using classical analytical methods easily accessible in those countries, four UV-Visible spectrophotometric methods for one ... In the framework of fighting against the poor quality medicines sold in developing countries using classical analytical methods easily accessible in those countries, four UV-Visible spectrophotometric methods for one antimalarial (quinine) and two antibiotics (amoxicillin and metronidazole) have been developed and validated according to the total error strategy using the accuracy profiles as a decision tool. The dosing range was 2 - 10 μg/mL (for quinine sulfate in tablet), 4 - 12 μg/mL (for quinine bichlorhydrate in oral drop-metronidazole benzaote in oral suspension) and 15 - 35 μg/mL (for amoxicillin trihydrate in capsule). The validated methods were then applied in determining the content of some analogous medicines sold in the Democratic Republic of Congo. Thus, the proposed UV-Visible spectrophotometric methods are simple and suitable to quantify quinine, amoxicillin and metronidazole in different pharmaceutical forms. 展开更多
关键词 POOR Quality MEDICINES UV-VISIBLE spectrophotometric Methods QUININE Amoxicillin METRONIDAZOLE VALIDATION Total Error Accuracy Profiles
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A Novel Spectrophotometric Method for Determination of Gabapentin in Pharmaceutical Formulations Using 2,5-Dihydroxybenzaldehyde 被引量:1
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作者 Magda S. Saleh Ahmed K. Youssef +1 位作者 Elham Y. Hashem Doaa A. Abdel-Kader 《Computational Chemistry》 2014年第2期22-30,共9页
A highly simple, rapid, sensitive and selective method is developed for spectrophotometric determination of gabapentin in pure form as well as in pharmaceutical formulations. The method is based on the formation of a ... A highly simple, rapid, sensitive and selective method is developed for spectrophotometric determination of gabapentin in pure form as well as in pharmaceutical formulations. The method is based on the formation of a yellow Schiff base derived from the condensation of gabapentin drug (1-amino methyl) cyclo hexane acetic acid and 2,5-dihydroxybenzaldehyde (DHBA) exhibiting a maximum absorbance at 445 nm. The composition, molar absorptivity and effect of different excipient have been determined spectrophotometrically. Under optimized experimental conditions, Beer’s law is obeyed in the concentration range 2.57 - 37.25 μg/ml. The method is validated with respect to accuracy, precision, limit of detection and limit of quantification. The Sandell sensitivity, correlation coefficient and regression equation are calculated. The equilibrium constant and free energy change using Benesi-Hildebrand plot are also determined. The Schiff base derived from condensation of gabapentin with DHBA is also synthesized and characterized. The condensation reaction mechanism has been proposed. 展开更多
关键词 GABAPENTIN 2 5-Dihydroxybenzaldehyde PHARMACEUTICAL Formulations spectrophotometric ANALYSIS
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New simple spectrophotometric method for determination of the binary mixtures(atorvastatin calcium and ezetimibe;candesartan cilexetil and hydrochlorothiazide) in tablets 被引量:1
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作者 Tarek S.Belal Hoda G.Daabees +2 位作者 Magdi M.Abdel-Khalek Mohamed S.Mahrous Mona M.Khamis 《Journal of Pharmaceutical Analysis》 SCIE CAS 2013年第2期118-126,共9页
A new simple spectrophotometric method was developed for the determination of binary mixtures without prior separation.The method is based on the generation of ratio spectra of compound X by using a standard spectrum ... A new simple spectrophotometric method was developed for the determination of binary mixtures without prior separation.The method is based on the generation of ratio spectra of compound X by using a standard spectrum of compound Y as a divisor.The peak to trough amplitudes between two selected wavelengths in the ratio spectra are proportional to concentration of X without interference from Y.The method was demonstrated by determination of two drug combinations.The first consists of the two antihyperlipidemics:atorvastatin calcium(ATV) and ezetimibe(EZE),and the second comprises the antihypertensives:candesartan cilexetil(CAN) and hydrochlorothiazide(HCT).For mixture 1,ATV was determined using 10 μg/mL EZE as the divisor to generate the ratio spectra,and the peak to trough amplitudes between 231 and 276 nm were plotted against ATV concentration.Similarly,by using 10 μg/mL ATV as divisor,the peak to trough amplitudes between 231 and 276 nm were found proportional to EZE concentration.Calibration curves were linear in the range 2.5-40 mg/mL for both drugs.For mixture 2,divisor concentration was 7.5 μg/mL for both drugs.CAN was determined using its peak to trough amplitudes at 251 and 277 nm,while HCT was estimated using the amplitudes between 251 and 276 nm.The measured amplitudes were linearly correlated to concentration in the ranges 2.5-50 and 1-30 μg/mL for CAN and HCT,respectively.The proposed spectrophotometric method was validated and successfully applied for the assay of both drug combinations in several laboratory-prepared mixtures and commercial tablets. 展开更多
关键词 spectrophotometric analysis Ratio spectra Atorvastatin Ezetimibe Candesartan Hydrochlorothiazide
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Solid-liquid Extraction Spectrophotometric Determination of Copper with 2,9-dimethyl-1,10-phenanthroline
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作者 Peng, B Gao, JZ +3 位作者 Hu, GL Fan, HY Kang, JW Deng, HL 《Rare Metals》 SCIE EI CAS CSCD 2001年第4期213-216,共4页
Solid liquid extraction of copper ion (I) with 2, 9-dimethyl-1, 10-phenanthroline (neo-cuproine, DMP) into molten naphthalene followed by chloroform spectrophotometric determination has been studied experimentally. Th... Solid liquid extraction of copper ion (I) with 2, 9-dimethyl-1, 10-phenanthroline (neo-cuproine, DMP) into molten naphthalene followed by chloroform spectrophotometric determination has been studied experimentally. The ternary complex Cu(I)-DMP-ClO4 was extracted quantitatively into molten naphthalene in the range of pH from 5 to 6 at 85 C-. Absorbance was spectrophotometrically determined at 459 nm against the reagent blank after the solid naphthalene layer was anhydrously dissolved in chloroform. Beer's law is obeyed over a concentration range of 0.5-70 mug/mL. The molar absorptivity and Sandell's sensitivity are 1.0x10(4) L/(mol(.)cm) and 0.0099 mug(.)cm(2) respectively. In addition, the various conditions on determination and the interference of coexisted ions were discussed, and the method was applied to the determination of copper ion both in tea samples and cadmium sulfate reagents. The results are in good agreement with those obtained by ICP AES method. 展开更多
关键词 solid-liquid extraction spectrophotometric determination molten naphthalene COPPER DMP
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β-CORRECTION SPECTROPHOTOMETRIC DETERMINATION OF ALUMINIUM, USING THE AL(Ⅲ)-PF-OP REACTION
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作者 Hong Wen GAO Feng ZOU and Peng Fei ZHANG(Huaibei Environmental Monitoring Centre, Huaibei, Anhui Province, 235000Huaibei Beer-Manusfacturing Plant, Anhui Province,235000 Department of Chemistry,Huaibei Coal Teachers College, Anhui Province, 235000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第8期679-680,共2页
Aluminium has been determined by β-correction spectrophotometer with phenylfluorone (PF)and a non-ionic surfactant, emulsifying OP in PH 8 ammoniacal buffer solution. β-correction spectrophotometric method can elimi... Aluminium has been determined by β-correction spectrophotometer with phenylfluorone (PF)and a non-ionic surfactant, emulsifying OP in PH 8 ammoniacal buffer solution. β-correction spectrophotometric method can eliminate completely the effect of excess PF to increase the analytical sensitivity and decrease error. The results have Shown that Beer's law was obeyed over the concentration range 0-15μg Al (Ⅲ)/25ml and the relative standard deviation was less than 3.3%. 展开更多
关键词 OP spectrophotometric DETERMINATION OF THE USING CORRECTION ALUMINIUM PF
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Azeotropic mixture used for development and validation of Lornoxicam in bulk and its tablet dosage form by spectrophotometric method
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作者 Prajesh Prajapati Vipul Vaghela +3 位作者 Deepak Rawtani Harshad Patel Jasmin Kubavat Dharmendra Baraiya 《Journal of Pharmaceutical Analysis》 SCIE CAS 2012年第4期306-309,共4页
A novel,safe,economic and sensitive method of spectrophotometric estimation has been developed using Azeoptropic mixture (water∶methanol:60∶40,v/v) for the quantitative determination of Lornoxicam,a practically wate... A novel,safe,economic and sensitive method of spectrophotometric estimation has been developed using Azeoptropic mixture (water∶methanol:60∶40,v/v) for the quantitative determination of Lornoxicam,a practically water-insoluble drug.Hence,Lornoxicam stock solution was prepared in Azeoptropic mixture.Lornoxicam showed maximum absorbance at 383 nm.Beer's law was obeyed in the concentration range 4-24 μg/mL with regression coefficient of 0.999.The method was validated in terms of linearity (R2=0.999),precision (CV for intra-day and inter-day was 0.28 0.68 and 0.12-0.92,respectively),accuracy (98.03-100.59% w/w) and specificity.This method is simple,precise,accurate,sensitive and reproducible and can be used for the routine quality control testing of the marketed formulations. 展开更多
关键词 ANALGESIC Chlortenoxicam LORNOXICAM Oxicam spectrophotometric Azeotropic mixture
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Spectrophotometric Simultaneous Determination of Zinc(II), Manganese(II) and Iron(II) in Pharmaceutical Preparations Using OSC-PLS
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作者 Ali NIAZI zadeh YAZDANIPOUR +2 位作者 ohammad GOODARZI amidreza KAMKAR Ali RAFINEJAD 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第10期1347-1350,共4页
This work reports the spectrophotometric simultaneous determination of zinc(Ⅱ), manganese(Ⅱ) and iron(Ⅱ) in pharmaceutical preparation, using orthogonal signal correctionpartial least squares (OSC-PLS). All... This work reports the spectrophotometric simultaneous determination of zinc(Ⅱ), manganese(Ⅱ) and iron(Ⅱ) in pharmaceutical preparation, using orthogonal signal correctionpartial least squares (OSC-PLS). All the factors affecting on the sensitivity were optimized and the linear dynamic range for determination of these metals was found. The PLS modeling was used for the multivariate calibration of the spectrophotometric data. The OSC was used for preprocessing of data matrices and the prediction results of model. The experimental calibration matrix was designed by measuring the absorbance over the range 450-570 nm for 21 samples of 0.05-1.05, 0.10-1.10 and 0.05-1.05μg·mL^-1 of zinc(Ⅱ), manganese(Ⅱ) and iron(Ⅱ), respectively. The RMSEP for zinc(Ⅱ), manganese(Ⅱ) and iron(Ⅱ) using OSC-PLS were 0.0164, 0.0132, 0.0146, respectively. The proposed method was successfully applied the determination of zinc(Ⅱ), manganese(Ⅱ) and iron(Ⅱ) in pharmaceutical preparations. 展开更多
关键词 Zinc(Ⅱ) manganese(Ⅱ) iron(Ⅱ) spectrophotometric OSC-PLS PHARMACEUTICAL
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Spectrophotometric Determination of Trace Chromium(VI) in Mass Chromium(III)
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作者 Zi Gang XU Xian Hong WEN Qing Zhou WU 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第7期635-636,共2页
The method for the sepration and determination of trace Cr(VI) exiting in mass Cr(III) has been researched. The method is highly sensitive and less interference, but is simple and useful for analysis trace Cr(VI).
关键词 spectrophotometric CR(VI) CR(III) diphenyl carbazide(DPC) 4-methyl-benzene sulfonic acid
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SPECTROPHOTOMETRIC ANALYSIS OF MIXTURES OF TRACE METAL BY DOUBLE-SYSTEM AND MULTIVARIATE CALIRRATION
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作者 Yong Nian NI Xin Ming YIN Department of Chemistry,Jiangxi University,Nanchang,33007 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第2期157-158,共2页
In this paper,a new method for simultaneous spectrophotometric analysis of multi- component with double-system was developed.The multivariate calibration method,principal component analysis-partial least squares(PCA-P... In this paper,a new method for simultaneous spectrophotometric analysis of multi- component with double-system was developed.The multivariate calibration method,principal component analysis-partial least squares(PCA-PLS),was described and applied to the processing of measurement data.A demonstration,simultaneous determination of cobalt,nickel,copper,zinc and iron with double-system(5-Br-PADAP and PAR as chromogenic chelate reagents,respectively) was given.The results showed that the method with douhle-system gave better precision than those with single system and MLR(in this paper,AKC method was selected)did not give satis- fied precision in any situation. 展开更多
关键词 PLS PCR spectrophotometric ANALYSIS OF MIXTURES OF TRACE METAL BY DOUBLE-SYSTEM AND MULTIVARIATE CALIRRATION APPI RSD
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SPECTROPHOTOMETRIC STUDY OF DDQ CHARGE-TRANSFER COMPLEXES WITH 1,10-PHENANTHROLINE AND ITS DERIVATIVES
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作者 Shen Yang TONG Li NA 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第3期201-204,共4页
1,10-phenanthroline and its derivatives can form charge-transfer complexes with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone(DDQ).The absorption spectra and conditions of complex formation,such as the reaction time,the q... 1,10-phenanthroline and its derivatives can form charge-transfer complexes with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone(DDQ).The absorption spectra and conditions of complex formation,such as the reaction time,the quantity of DDQ, and the solvents, have been studied.After the HMO calculation of phenanthrolines,the molar absorptivities were found to depend on the substituents on the phenanthroline rings. 展开更多
关键词 DDQ CT ab spectrophotometric STUDY OF DDQ CHARGE-TRANSFER COMPLEXES WITH 1 10-PHENANTHROLINE AND ITS DERIVATIVES ITS
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Study on the Spectrophotometric Determination of Rare Earths with a New Chromogenic Reagent Dibromo-p-methyl-chlorosulfonazo(DBMCSA)
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作者 Guo Zhen FANG Jiao PAN +1 位作者 Wei Liang AHOU Bu Lu XU(Deparment of Chemistry.East China Normal University3663 Zhongshan Road(N), Shanghai 200062) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第10期851-854,共4页
A new method for the determination of cerium subgroup rare earths was studied and reported ill this paper. It was found that cerium subgroup rare earth elements react with DBMCSA in 0.6 mol/L hydrochloric acid medium ... A new method for the determination of cerium subgroup rare earths was studied and reported ill this paper. It was found that cerium subgroup rare earth elements react with DBMCSA in 0.6 mol/L hydrochloric acid medium to form stable blue complexes. The absorbances of equal amounts of cerium subgroup rare earths are close to each other at their maximum adsorptive wavelength (641 nm). Beer's law is obeyed for 0-20 mu g of I ars earths in 25 mi of solution. The method has been applied to the determination of the total amount of cerium subgroup rare earths in steel and cast iron samples with satisfactory results. 展开更多
关键词 spectrophotometric determination rare earths dibromo-p-methyl-chlorosulfonazo (DBMCSA)
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Liquid waveguide capillary cell for the spectrophotometric determination of nanomolar iodate concentrations in marine waters
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作者 Jianrong Lin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第3期103-108,共6页
A new spectrophotometric method based on a liquid waveguide capillary cell for an enhanced detection was developed to measure nanomolar iodate concentrations.This method has a detection limit and precision of 1-2 nmol... A new spectrophotometric method based on a liquid waveguide capillary cell for an enhanced detection was developed to measure nanomolar iodate concentrations.This method has a detection limit and precision of 1-2 nmol/L,which is equivalent to 10%that of conventional methods,a recovery of 97.7%-104.0%,and a working range of 10-120 nmol/L.Water samples were collected from three estuaries and one coastal ocean for testing,and the proposed technique detected as low as 11 nmol/L and 18 nmol/L iodate in these samples.This newly developed method is helpful in understanding the biogeochemical cycle of iodine in nature. 展开更多
关键词 IODATE liquid waveguide capillary cell spectrophotometric determination
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SPECTROPHOTOMETRIC STUDY OF BIMETALLIC TERNARY COMPLEX OF LANTHANUM——COPPER WITH ALIZARIN FLUORINE BLUE
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《Chemical Research in Chinese Universities》 SCIE CAS 1986年第1期65-75,共11页
The bimetallic ternary complex formation in the aqueous solution of La and Cu with alizarin fluorine blue (AFB) was studied by spectrophotometry.The ternary complex LaCu3(AFB)3 has maximum light absorption at 550nm.Th... The bimetallic ternary complex formation in the aqueous solution of La and Cu with alizarin fluorine blue (AFB) was studied by spectrophotometry.The ternary complex LaCu3(AFB)3 has maximum light absorption at 550nm.The colour reaction selectivity is fairly good and the method can be applied to the direct photometric determination of copper in lanthanum or some pure metals.A new mathematical approach to the treatment of spectrophotometric data for differentiation between mononuclear and polynuclear in solution is presented.The improvable fixed logarithm method is for complexes of the type MmBn(m=n) or MmBn(m=n).We report that La(Ⅲ) combines with AFB at pH 4.5 to form a single complex,withm=n=2,La2(AFB)2. 展开更多
关键词 AFB La spectrophotometric STUDY OF BIMETALLIC TERNARY COMPLEX OF LANTHANUM COPPER WITH ALIZARIN FLUORINE BLUE
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