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A UV cross-linked gel polymer electrolyte enabling high-rate and high voltage window for quasi-solid-state supercapacitors 被引量:1
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作者 Yuge Bai Chao Yang +6 位作者 Boheng Yuan Hongjie Li Weimeng Chen Haosen Yin Bin Zhao Fei Shen Xiaogang Han 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期41-50,I0002,共11页
Serving as a promising alternative to liquid electrolyte in the application of portable and wearable devices,gel polymer electrolytes(GPEs)are expected to obtain more preferable properties rather than just be satisfie... Serving as a promising alternative to liquid electrolyte in the application of portable and wearable devices,gel polymer electrolytes(GPEs)are expected to obtain more preferable properties rather than just be satisfied with the merits of high safety and deformability.Here,an easy-operated method is employed to fabricate cross-linked composite polymer membranes used for GPEs assisted by UV irradiation,in which N-doped carbon quantum dots(N-CQDs)and TiO2are introduced as photocatalysts and additives to improve the performances of GPEs.Specifically,N-CQDs participate as a cross-linker to construct the inner porous structure,and TiO2nanoparticles serve as a stabilizer to improve the electrochemical stability of GPEs under high voltage(3.5 V).The excellent thermal and mechanical stability of the membrane fabricated in this work guarantee the safety of the supercapacitors(SCs).This GPE based SC not only exhibits prominent rate performance(105%capacitance retention at the current density of 40A g^(-1))and cyclic stability(85%at 1 A g^(-1)under 3.5 V after 20,000 cycles),but also displays remarkable energy density(42.88 Wh kg^(-1))with high power density(19.3 k W kg^(-1)).Moreover,the superior rate and cycling performances of the as-prepared GPE based flexible SCs under flat and bending state confirm the feasibility of its application in flexible energy storage devices. 展开更多
关键词 Gel polymer electrolyte uv cross-linking Energy density High voltage window
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HPLC-UV法测定舒肝和胃丸中α-香附酮和香附烯酮的含量
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作者 宋瑩 崔业波 +1 位作者 张大勇 马晓静 《中国医药导刊》 2024年第3期260-263,共4页
目的:建立舒肝和胃丸中α-香附酮和香附烯酮的高效液相色谱(HPLC-UV)含量测定法,为该制剂中醋香附含量的质量控制提供依据。方法:对舒肝和胃丸中α-香附酮和香附烯酮同时进行含量测定。采用Agilent ZORBAX SB-C18色谱柱(4.6 mm×250... 目的:建立舒肝和胃丸中α-香附酮和香附烯酮的高效液相色谱(HPLC-UV)含量测定法,为该制剂中醋香附含量的质量控制提供依据。方法:对舒肝和胃丸中α-香附酮和香附烯酮同时进行含量测定。采用Agilent ZORBAX SB-C18色谱柱(4.6 mm×250 mm,5μm),流动相为甲醇和水(65∶35),流速1.0 mL·min^(-1),检测波长254 nm,柱温30℃,进样量5μL。结果:采用该方法得到的舒肝和胃丸色谱图中,α-香附酮和香附烯酮色谱峰与相邻色谱峰分离效果较好,满足含量测定的要求;指标性成分α-香附酮、香附烯酮分别在0.08036~0.80360μg、0.2112~2.1120μg范围内线性关系良好,相关系数均为1.000;平均加标回收率分别为102.0%(RSD:1.6%,n=6),102.4%(RSD:2.0%,n=6);稳定性(24 h)、重复性、精密度良好。结论:本研究建立的α-香附酮和香附烯酮HPLC-UV含量测定方法简单、快捷、准确,可为舒肝和胃丸中醋香附含量的控制提供依据。 展开更多
关键词 舒肝和胃丸 Α-香附酮 香附烯酮 HPLC-uv 含量测定
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DETERMINATION OF DISSOLVED ORGANIC CARBON IN SEAWATER USING UV/PERSULPHATE METHOD AND HTCO METHOD 被引量:9
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作者 王江涛 张正斌 刘莲生 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1997年第1期25-31,共7页
A comparison between the high-temperature catalytic oxidation method (HTCO) and the UV/persulphate method for the determination of dissolved organic carbon (DOC)in seawater is presented in this paper. In seawater samp... A comparison between the high-temperature catalytic oxidation method (HTCO) and the UV/persulphate method for the determination of dissolved organic carbon (DOC)in seawater is presented in this paper. In seawater sample chloride ion can affect the oxidation efficiency of the UV/persulphate method if the asymptotic concentration of persulphate is not reached.During HTCO analysis, blanks that appear to originate mainly from the catalyst are high and far from constant.If the blanks are well estimated and correction is made, the difference of determined DOC values between the UV/persulphatemethod and the HTCO mehod is small, the HTCO values being slightly higher. 展开更多
关键词 DOC uv/persulphate method HTCO method
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Development of an HPLC–UV assay method for the simultaneous quantification of nine antiretroviral agents in the plasma of HIV-infected patients 被引量:4
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作者 Nitin Charbe Sara Baldelli +3 位作者 Valeria Cozzi Simone Castoldi Dario Cattaneo Emilio Clementi 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第6期396-403,共8页
A new method using high-performance liquid chromatography coupled with ultra violet detection(HPLC–UV)was developed and validated for the simultaneous quantification of atazanavir,dolutegravir,darunavir,efavirenz,etr... A new method using high-performance liquid chromatography coupled with ultra violet detection(HPLC–UV)was developed and validated for the simultaneous quantification of atazanavir,dolutegravir,darunavir,efavirenz,etravirine lopinavir,raltegravir,rilpivirine and tipranavir in human plasma.For the first time we reported here the development and validation of an HPLC–UV assay to quantify the frequently administered 9antiretroviral compounds including dolutegravir and rilpivirine.A simple solid phase extraction procedure was applied to 500 μL aliquots of plasma.The chromatographic separation of the drugs and internal standard(quinoxaline) was achieved with a gradient of acetonitrile and sodium acetate buffer on a C_(18) reverse-phase analytical column with a 25 min analytical run time.Calibration curves were optimised according to the therapeutic range of drug concentrations in patients,and the coefficient of determination(r^2) was higher than0.99 for all analytes.Mean intraday and interday precisions(RSD) for all compounds were less than 15.0%,and the mean accuracy(% deviation from nominal concentration) was also found to be less than 15.0%.Extraction recovery range was between 80% and 120% for all drugs analysed.The solid phase extraction and HPLC–UV method enable a specific,sensitive,and reliable simultaneous determination of nine antiretroviral agents in plasma.Good extraction efficiency and low limit of HPLC–UV quantification make this method suitable for use in clinical trials and therapeutic drug monitoring. 展开更多
关键词 HPLC–uv ANTIRETROVIRALS BIOANALYTICAL method validation
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COMPARISON OF HTC METHOD AND UV/PERSULPHATE METHOD TO DETERMINE COLLOIDAL ORGANIC CARBON IN SEAWATER 被引量:2
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作者 王江涛 赵卫红 +1 位作者 谭丽菊 张正斌 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2000年第1期80-84,共5页
The application of cross flow ultrafiltration(CFF) techniques to separate colloidal organic carbon(COC) from truly dissolved organic carbon(TDOC) was investigated; COC and TDOC were determined by the high temperature ... The application of cross flow ultrafiltration(CFF) techniques to separate colloidal organic carbon(COC) from truly dissolved organic carbon(TDOC) was investigated; COC and TDOC were determined by the high temperature combustion method(HTC) and UV/persulphate method. It was found that CFF can quantitatively separate COC from seawater. The determination results by the HTC and UV/persulphate method for COC and TDOC showed little difference, which suggested that the oxidation efficiency of the two methods are identical. Colloidal particles have no remarkable influence on the oxidation efficiency of the UV/persulphate method. 展开更多
关键词 cross flow ULTRAFILTRATION COLLOIDAL organic carbon high temperature combustion method uv/persulphate method
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Analytical Method Development and Validation of Filgrastim by UV and RP-UFLC Methods 被引量:1
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作者 Husna Kanwal Qureshi Ciddi Veeresham Chinta Srinivas 《American Journal of Analytical Chemistry》 2021年第10期333-346,共14页
The research work was carried out for establishing a new Ultra Violet (UV)— Visible spectroscopy and Reverse phase-Ultra Fast Liquid Chromatography (RP-UFLC) method for the analysis and quantification of a biosimilar... The research work was carried out for establishing a new Ultra Violet (UV)— Visible spectroscopy and Reverse phase-Ultra Fast Liquid Chromatography (RP-UFLC) method for the analysis and quantification of a biosimilar drug, Filgrastim. Filgrastim or recombinant methionyl granulocyte colony stimulating factor (rGCSF) is a glycoprotein. It has a biological action essential for proliferation and differentiation of hematopoetic and progenitor cells. The UV and RP-UFLC work was carried on a Shimadzu UV1800 Spectrophotometer and Shimadzu Prominence LC-20AD UFLC systems, respectively. The <i>λ</i><sub>max</sub> of filgrastim was found to be 215 nm. The correlation coefficient by UV spectroscopy was found to be 0.9994 for the concentration range of 1 to 3 μg/ml in double distilled water. The Reverse phase UFLC was done by using Phenomenex C4 (25 cm × 0.46 cm internal diameter) 15 μ, 300 A° analytical column. The optimized mobile phase for binary elution was Acetonitrile and double distilled water (80:20) with a flow rate of 1 ml/min. The retention time of drug was at 3.2 min. It was observed that the response of the detector was linear in the range of 5 - 15 μg/ml with correlation coefficient value of 0.999. After developing the methods, it was assured for the intended use by validation of the analytical parameters like linearity, accuracy, precision, limit of detection, limit of quantitation, ruggedness and robustness. The results of all the parameters for both the methods were found to be within the acceptance criteria as per the International Council for Harmonisation (ICH) guidelines. 展开更多
关键词 BIOSIMILARS Filgastim method Development RP-UFLC uv Visible Spectroscopy VALIDATION
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Quality Control of Tramadol in Kisangani: Development, Validation, and Application of a UV-Vis Spectroscopic Method 被引量:4
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作者 Marguerite Borive Amani Jérémie Mbinze Kindenge +4 位作者 Emile Tweni Baruti Elodie Nsasi Bakiantima Salomon Batina Agasa Philippe Hubert Roland Marini Djang’eing’a 《American Journal of Analytical Chemistry》 2021年第8期295-309,共15页
<strong>Context:</strong> Substandard and falsified medicines are circulating in low-income countries mostly without any control. We availed a simple and not expensive UV-Vis spectroscopic method to evalua... <strong>Context:</strong> Substandard and falsified medicines are circulating in low-income countries mostly without any control. We availed a simple and not expensive UV-Vis spectroscopic method to evaluate the quality of tramadol in Kisangani before and during the Covid-19 period. <strong>Methods:</strong> For the analytical quantitative method, an experimental design was applied to set up the optimal levels of the selected factors, namely, pH of dissolution medium, type of cuvette, and wavelength. Taking into account the capsule pharmaceutical formulation within 80 - 120 μg&middotmL<sup>-1</sup> concentration range, we analyzed 89 tramadol samples from pharmacies and hospitals of the six Kisangani municipalities. <strong>Results:</strong> pH showed a significant effect on absorbance, whereas quartz cuvette and wavelength did not. A typical 100 μg&middotmL<sup>-1</sup> tramadol solution gave an absorbance of 0.64 at 272 nm. Validation highlighted a matrix effect observed with a 6% bias. A correction factor of 0.9372 allowed to improve the accuracy profile, which were then totally included within the 10% acceptance limits. Quality control revealed that 25 samples out of 89 were not compliant in terms of manufacturing license, registration status in DRC and content as well. <strong>Conclusion:</strong> This study showed that the strengthening of analytical strategy in Kisangani is a need. 展开更多
关键词 TRAMADOL uv-Vis Spectroscopy method Development VALIDATION Quality Control
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Preparation and UV property of size-controlled monodisperse nickel nanoparticles (<10 nm) by reductive method 被引量:1
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作者 Xiao Guo Feng Zheng +2 位作者 Min Guo Mei Zhang Kuo-Chih Chou 《Rare Metals》 SCIE EI CAS CSCD 2013年第2期179-185,共7页
Nickel nanoparticles (〈10 nm) were success fully synthesized using a reductive method of nickel chloride with sodium borohydride in the ethanol/poly vinylpyrrolidone (PVP) system. The effects of three fac tors, s... Nickel nanoparticles (〈10 nm) were success fully synthesized using a reductive method of nickel chloride with sodium borohydride in the ethanol/poly vinylpyrrolidone (PVP) system. The effects of three fac tors, such as the concentration of the nickel ions, the time of reaction, and the amount of PVP (surfactant), were discussed. The possible growth process of the particles and optimum reactive conditions was also investigated. The result of transmission electron microscopy (TEM) reveals that these nickel nanoparticles are spherical. The average diameter could be controlled as 25 nm under selected conditions. Highresolution TEM and energydispersive spectroscopy results indicates that the nickel nanoparticles are pure. The UVvisible light absorption spectrum shows that the peaks of nickel nanoparticles moves toward the short wavelength along with the decrease of sizes. 展开更多
关键词 Reductive method Nickel nanoparticles Size controllable uv-visible light absorption
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Development of simple HPLC/UV with a column-switching method for the determination of nicotine and cotinine in hair samples
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作者 Masayoshi Tsuji Yayoi Mori +7 位作者 Hideyuki Kanda Teruna Ito Tomoo Hidaka Takeyasu Kakamu Tomohiro Kumagai Takehito Hayakawa Yoneatsu Osaki Tetsuhito Fukushima 《Health》 2013年第4期687-694,共8页
Nicotine and cotinine in hair are good biomarkers for assessing long-term exposure to smoking. However, analytical devices such as GC/MS are associated with high cost and are not widely used. HPLC/UV is used widely in... Nicotine and cotinine in hair are good biomarkers for assessing long-term exposure to smoking. However, analytical devices such as GC/MS are associated with high cost and are not widely used. HPLC/UV is used widely in laboratories, but is unsuitable for measurement of minor constituents, except when using the column-switching method. Thus, we aimed to establish a simple, inexpensive and sensitive method based on HPLC/UV with column switching for measuring nicotine and cotinine in hair. First, we compared the presence and absence of a column selection unit. We then measured amounts of nicotine and cotinine in hair samples collected from the general population, and compared both the corresponding levels and the detection limits with those in previous studies. Finally, initial and running costs of HPLC/UV were compared with other analytical methods. As one of the results, the areas of nicotine and cotinine measured by HPLC/UV with column-switching method were 12.9 and 16.9 times greater, respectively, than those without the column-switching method. The amount of nicotine and cotinine in hair was significantly correlated to number of cigarettes smoked per day (r = 0.228, p = 0.040). In addition, the HPLC/UV method showed similar sensitivity and detection limit (nicotine, 0.10 ng/mg;cotinine, 0.08 ng/mg) as reported in previous studies. The cost of the HPLC/UV method is lower than that of other analytical methods. We were able to establish a low-cost method with good sensitivity for measuring nicotine and cotinine in hair. The HPLC/UV with a column-switching method will be useful as a first step in screening surveys in order to better understand the effects of smoking exposure. 展开更多
关键词 HPLC/uv COLUMN-SWITCHING method NICOTINE HAIR COTININE
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Determination of Fenofibrate and the Degradation Product Using Simultaneous UV-Derivative Spectrometric Method and HPLC
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作者 Fathy M. M. Salamaa Mohamed W. I. Nassar +2 位作者 Mohie M. K. Sharaf El-Din Khalid A. M. Attia Mohamed Yousri Kaddah 《American Journal of Analytical Chemistry》 2011年第3期332-343,共12页
Two new selective, precise, and accurate methods were developed for the determination of fenofibrate in the presence of its basic degradation product. In the first method fenofibrate was determined using an algorithm ... Two new selective, precise, and accurate methods were developed for the determination of fenofibrate in the presence of its basic degradation product. In the first method fenofibrate was determined using an algorithm bivariate calibration derivative method, in which an optimum pair of wavelengths was chosen for the determination of different binary mixtures. In the second method (HPLC), separation was achieved on RESTEK Pinnacle II phenyl column (5 μm, 250 × 4.6 mm) and Pinnacle II phenyl (5 μm, 10 × 4 mm) guard cartridge using a mobile phase consisting of methanol –0.1% phosphoric acid (60:40, v/v) at a flow rate 2 mL●min–1, and the column oven temperature was set at 50°C. The UV detector was time programmed at 302 nm and 289 nm for the internal standard (I.S.) and fenofibrate, respectively. The proposed methods were successfully applied for the determination of fenofibrate and its degradation product in the laboratory-prepared mixture and in pharmaceutical formulation. The assay results obtained using the bivariate method were statistically compared to those of the HPLC method and good agreement was observed. 展开更多
关键词 FENOFIBRATE Stability Degradation Product uv DERIVATIVE Spectrometric method HPLC
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Natural products and extracts from plants as natural UV filters for sunscreens:A review 被引量:1
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作者 Liyan Li Lan Chong +3 位作者 Tao Huang Yunge Ma Yingyan Li Hui Ding 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第3期183-195,共13页
Although solar exposure is necessary for human health,phototoxicology induced by excessive UVB and UVA radiation,which involves sunburns,skin aging and even tu-morigenesis,has been widely researched.Sunscreen is one o... Although solar exposure is necessary for human health,phototoxicology induced by excessive UVB and UVA radiation,which involves sunburns,skin aging and even tu-morigenesis,has been widely researched.Sunscreen is one of the most important ways to protect skin from UV phototoxic damage.As well as inorganic and organic UV filters,some natural products or plant extracts with aromatic rings in their structures,such as flavonoids or polyphenols,can absorb UV to reduce sunburn,acting as a natu-ral UV filter;they also show antioxidant or/and anti-inflammatory activity.This could explain why,although there are no officially approval natural commercial sun-filters,more and more commercial sunscreen products containing plant extracts are avail-able on the market.Here we summarize articles focusing on natural UV filters from plant published in the last 6 years,selecting the most significant data in order to better understand the photoprotective activity of natural products and extracts from plants,including their major constituents and main biological effects,methods for evaluating UV radiation resistance,anti-UV radiation experimental models and anti-UV radiation mechanisms. 展开更多
关键词 ANTIOXIDANTS evaluation method natural products and extracts from plants natural uv filters SPF value
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Narrowband EUV Sc/Si Multilayer for the Solar Upper Transition Region Imager at 46.5 nm 被引量:1
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作者 Runze Qi Jiali Wu +7 位作者 Jun Yu Chunling He Li Jiang Yue Yu Zhe Zhang Qiushi Huang Zhong Zhang Zhanshan Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第10期210-217,共8页
The transition region is the key region between the lower solar atmosphere and the corona, which has been limitedly understood by human beings. Therefore, the Solar Upper Transition Region Imager(SUTRI) was proposed b... The transition region is the key region between the lower solar atmosphere and the corona, which has been limitedly understood by human beings. Therefore, the Solar Upper Transition Region Imager(SUTRI) was proposed by Chinese scientists and launched in 2022 July. Right now, the first imaging observation of the upper transition region around 46.5 nm has been carried out by SUTRI. To ensure the spectral and temporal resolution of the SUTRI telescope, we have developed a narrowband Sc/Si multilayer. Based on the extreme ultraviolet(EUV)reflectivity measurements, the multilayer structure has been modified for ensuring the peak position of reflectivity was at 46.5 nm. Finally, the narrowband Sc/Si multilayer was successfully deposited on the hyperboloid primary mirror and secondary mirrors. The deviation of multilayer thickness uniformity was below than 1%, and the average EUV reflectivity at 46.1 nm was 27.8% with a near-normal incident angle of 5°. The calculated bandwidth of the reflectivity curve after primary and secondary mirrors was 2.82 nm, which could ensure the requirements of spectral resolution and reflectivity of SUTRI telescope to achieve its scientific goals. 展开更多
关键词 Astronomical Instrumentation methods and Techniques instrumentation:high angular resolution Sun:uv radiation
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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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UV-Vis-SWNIR漫反射光谱结合偏最小二乘法测定蕨菜总多糖含量
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作者 李强 郝经文 陈乃东 《中成药》 CAS CSCD 北大核心 2023年第7期2244-2249,共6页
目的建立UV-Vis-SWNIR漫反射光谱结合偏最小二乘法测定蕨菜中总多糖的含量。方法收集140批样品,从中随机选取20份作为完全外部验证集样品,用于验证模型的可靠性和准确性;其余80批样品为校正集,40批样品为检验集,用于筛选蕨菜总多糖的定... 目的建立UV-Vis-SWNIR漫反射光谱结合偏最小二乘法测定蕨菜中总多糖的含量。方法收集140批样品,从中随机选取20份作为完全外部验证集样品,用于验证模型的可靠性和准确性;其余80批样品为校正集,40批样品为检验集,用于筛选蕨菜总多糖的定量模型光谱预处理方法、主因子数、UV-Vis-SWNIR光谱特征波长。结果采用一阶导数法对原始光谱预处理,主因子数为7,结合随机青蛙算法筛选建模波长为925~1084、890~910、560~820、525~540、451~520、385~445、251~270 nm时,所得预测模型校正集R^(2)值为0.9617,RMSEC值为0.167%,检验集R^(2)值为0.9332,RMSEP值为0.208%,完全外部验证误差范围为-0.741%~0.853%。结论该方法快速可行,可用于蕨菜总多糖含量的预测。 展开更多
关键词 蕨菜 总多糖 紫外-可见-短波近红外漫反射光谱 偏最小二乘法(PLS)
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Estimating Aluminum Leaching into Meat Baked with Aluminum Foil Using Gravimetric and UV-Vis Spectrophotometric Method
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作者 Layla A. Al Juhaiman 《Food and Nutrition Sciences》 2015年第5期538-545,共8页
Baking meat by wrapping them in Aluminum (Al) foil is common in many countries. The excessive use of Al foil in baking and the disagreement about using Al foils were the motivation to do this study especially after th... Baking meat by wrapping them in Aluminum (Al) foil is common in many countries. The excessive use of Al foil in baking and the disagreement about using Al foils were the motivation to do this study especially after the 2007 WHO/FDA Report. In this investigation, a gravimetric and a UV-Vis spectrophotometric method are used to estimate Aluminum (Al) leaching into meat baked by wrapping in Al foil. Three kinds of meat were used fish, cow stakes and chicken. The importance of Al exposure area was neglected by many studies. Five factors affecting Al leaching into meat are studied (baking temperature, baking time, additives, Al exposure area and weight of meat). The effect of cooking times (20, 40, 60 minutes) at 180℃ and cooking temperatures (160℃, 180℃, 200℃) at 60 minutes on the amount of Al leaching were evaluated. It was found that Al leaching into meat increased with increasing temperature, baking time, additives and Al exposure area. Moreover, Al exposure area was more effective than the weight of the meat. The Al leaching was highest in fish and lowest in chicken. Comparing the present results with the Provisional Tolerance Weekly Intake of Al approved by WHO/FDA, it shows that Al leaching into meat baked by wrapping in Al foil may add considerable doses into the diet. Continuous monitoring of Al foil used for baking meat is recommended. 展开更多
关键词 AL FOIL AL LEACHING into MEAT Weight Loss uv-VIS method Provisional Tolerable WEEKLY Intake
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Structural, Optical and Photocatalytic Properties of Cu2+ Doped ZnO Nanorods with Using HMTA Solvent Prepared by Hydrothermal Method
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作者 Nguyen Thi Tuyet Mai Nguyen Thi Lan +2 位作者 Trinh Xuan Anh Ta Ngoc Dung Huynh Dang Chinh 《Journal of Materials Science and Chemical Engineering》 2023年第7期20-30,共11页
In this experiment, Cu<sup>2+</sup> doped ZnO (Cu-ZnO) nanorods materials have been fabricated by hydrothermal method. Cu<sup>2+</sup> ions were doped into ZnO with ratios of 2, 5 and 7 mol.% (... In this experiment, Cu<sup>2+</sup> doped ZnO (Cu-ZnO) nanorods materials have been fabricated by hydrothermal method. Cu<sup>2+</sup> ions were doped into ZnO with ratios of 2, 5 and 7 mol.% (compared to the mole’s number of Zn<sup>2+</sup>). The hexamethylenetetramine (HMTA) solvent used for the fabrication of Cu-ZnO nanorods with the mole ratio of Zn<sup>2+</sup>:HMTA = 1:4. The characteristics of the materials were analyzed by techniques, such as XRD, Raman shift, SEM and UV-vis diffuse reflectance spectra (DRS). The photocatalytic properties of the materials were investigated by the decomposition of the methylene blue (MB) dye solution under ultraviolet light. The results show that the size of Cu-ZnO nanorods was reduced when the Cu<sup>2+</sup> doping ratio increased from 2 mol.% to 7 mol.%. The decomposition efficiency of the MB dye solution reached 92% - 97%, corresponding to the Cu<sup>2+</sup> doping ratio changed from 2 - 7 mol.% (after 40 minutes of ultraviolet irradiation). The highest efficiency for the decomposition of the MB solution was obtained at a Cu<sup>2+</sup> doping ratio of 2 mol.%. 展开更多
关键词 Cu2+ Doped ZnO Nanorods ZnO Nanomaterials Hexamethylenetetramine (HMTA) Photocatalytics Methylene Blue Hydrothermal method uv Irradiation
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STUDY ON THE ASSAY QUALITY OF FOOD GRADE GPR BY UV—VIS METHOD
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作者 刘雄亚 张大厚 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1993年第2期50-60,共11页
In this paper, the kind of remanent small molecules in unsaturated polyester res(?) (UP resin) , the best extractant and the best suitalbe extractive time for measuring the content of these small molecules were studie... In this paper, the kind of remanent small molecules in unsaturated polyester res(?) (UP resin) , the best extractant and the best suitalbe extractive time for measuring the content of these small molecules were studied using ultraviolet- visible spectrophotometry ( UV-VIS method). According to the principle of additivity lightness absorption for mixid solution, the contents of samll molecules in several kinds of cured UP resin were measured. It is pointed out that the UV-VIS method in the assay quality of food grade GRP products is more suitable to China. 展开更多
关键词 ultraviolet- visible spectrophotometry ( uv- VIS ) method food grade GRP cured UP resin extractant remanent small molecules
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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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靛蓝提取物中靛蓝和靛玉红的分析方法比较
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作者 王成章 颜洋洋 +3 位作者 周昊 刘丹阳 商士斌 张华兴 《生物质化学工程》 2024年第1期18-26,共9页
以靛膏为原料,采用盐酸酸化、葡萄糖还原和乙酸乙酯提取3种工艺制备靛蓝酸化物、靛蓝还原物和乙酸乙酯提取物。建立高效液相色谱(HPLC)法、紫外可见分光光度(UV)法和双波长紫外分光光度(dW-UV)法,分析3种靛蓝提取物中靛蓝和靛玉红的含量... 以靛膏为原料,采用盐酸酸化、葡萄糖还原和乙酸乙酯提取3种工艺制备靛蓝酸化物、靛蓝还原物和乙酸乙酯提取物。建立高效液相色谱(HPLC)法、紫外可见分光光度(UV)法和双波长紫外分光光度(dW-UV)法,分析3种靛蓝提取物中靛蓝和靛玉红的含量,并以Kolmogorov-Smirnov检验、Bland-Altman偏差图比较和Spearman检验确定3种样品各自最佳分析方法。结果表明:所建立的HPLC法、UV法和dW-UV法简单、准确、灵敏度高、稳定性好和重复性好。3种靛蓝提取物成分含量检测方法均遵从正态分布,两两测定值存在显著差异。UV法更适于分析靛蓝酸化物、靛蓝还原物中靛蓝含量;HPLC法更适于乙酸乙酯提取物中靛蓝、靛玉红含量分析。 展开更多
关键词 靛蓝 靛玉红 统计分析 HPLC法 uv光谱法
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烟草废弃物提取物的双水相萃取及其化妆品功效研究
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作者 沙云菲 熊骏威 +3 位作者 费婷 吴达 任爽 蒋汶 《轻工学报》 CAS 北大核心 2024年第2期80-86,93,共8页
采用双水相萃取法制备烟草废弃物提取物,探究不同萃取条件对其中上相多酚得率的影响,并探讨其抗氧化活性、紫外吸收特性和细胞毒性。结果表明:当料液质量比为1∶60,搅拌时间为30 min,(NH4)2SO4质量分数为23.3%,乙醇质量分数为23.5%时,... 采用双水相萃取法制备烟草废弃物提取物,探究不同萃取条件对其中上相多酚得率的影响,并探讨其抗氧化活性、紫外吸收特性和细胞毒性。结果表明:当料液质量比为1∶60,搅拌时间为30 min,(NH4)2SO4质量分数为23.3%,乙醇质量分数为23.5%时,上相多酚得率最高,为48.59 mg/g;该萃取条件下,烟草废弃物提取物具有较好的抗氧化活性,当质量浓度为2 mg/mL时,对DPPH自由基清除率达98%,对ABTS自由基清除率达78%;当提取物质量浓度为0.5 mg/mL时,具有较好的紫外吸收特性,有一定的光防护功效;当提取物质量浓度在0~1.2 mg/mL范围内时,对Hacat细胞无细胞毒性,有望成为天然无刺激的功效型化妆品原料。 展开更多
关键词 烟草废弃物 多酚 双水相萃取法 化妆品 紫外吸收特性 抗氧化活性
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