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131.
In this paper, the transport of Cu(II) in the presence of lipophilic Cu(II) organic complexes through permeation liquid membranes (PLMs) have been investigated. In natural waters, small organic compounds, which form liposoluble neutral complexes with Cu(II), are potentially toxic and bioavailable. Hence, to understand the role of liposoluble Cu(II) complexes in natural waters, four organic ligands: phthalic acid, bipyridyl, pyrocatechol and hydroxyquinoline, which form uncharged or lipophilic Cu(II) complexes, were tested. The results showed that the transport of lipophilic Cu(II) complexes through PLM depends on the lipophilicity of the complex. Applications of PLMs in natural waters are presented. 相似文献
132.
Immunoanalytical methods at a very low limit of detection (LOD) and a low limit of quantification (LOQ) are becoming more and more important for environmental analysis and especially for monitoring drinking water quality. Biosensors have suitable characteristics such as efficiency in allowing very fast, sensitive, and cost-effective detection. Here we describe a fully automated immunoassay for estrone with a LOD below 0.20 ng L–1 and a LOQ below 1.40 ng L–1. In contrast to common analytical methods such as GC-MS or HPLC-MS, the biosensor used requires no sample pre-treatment and pre-concentration. The basis of our sensitive assay is the antibody with a high affinity constant towards estrone. The very low amount of antibody per sample results in low validation parameters (LOD, LOQ, and IC50), but this assay for estrone represents the current device-related limitation of the River Analyser (RIANA). 相似文献
133.
Bar adsorptive micro-extraction using three powdered activated carbons (ACs) as adsorbent phases followed by liquid desorption and high performance liquid chromatography with diode array detection (BAμE(ACs)-LD/HPLC-DAD), was developed to monitor triazinic herbicides (atrazine, simazine and terbutylazine) in environmental water matrices. ACs used present apparent surface areas around 1000 m2 g−1 with an important mesoporous volume and distinct surface chemistry characteristics (pHPZC ranging from 6.5 to 10.4). The textural and surface chemistry properties of the ACs adsorbent phases were correlated with the analytical data for a better understanding of the overall enrichment process. Assays performed on 10 mL water samples spiked at the 10.0 μg L−1 levels under optimized experimental conditions yielded recoveries around 100% for the three herbicides under study. The analytical performance showed good precision (RSD < 15.0%), convenient detection limits (≈0.1 μg L−1) and suitable linearity (1.0-12.0 μg L−1) with good correlation coefficients (r2 > 0.9914). By using the standard addition method, the application of the present method on real water matrices, such as surface water and wastewater, allowed very good performances at the trace level. The proposed methodology proved to be a suitable sorptive extraction alternative for the analysis of priority pollutants with polar characteristics, showing to be easy to implement, reliable, sensitive and requiring a low sample volume to monitor triazinic compounds in water matrices. 相似文献
134.
Qing-Ping Mei Yi-Ke Tang Tai-Fu Li Li-Zhong Yao Qiong Yang Heng-Jian Zhang 《Analytical letters》2018,51(8):1176-1193
The calibration model of near-infrared (NIR) spectra established using the Kalman filter-partial least square (partial least squares combined with a Kalman filter) method can be adapted to outdated equipment, environmental changes, external samples, and other applications. However, the variance of the measurement noise estimation for NIR spectrum measurements cannot be easily obtained using Kalman filter-partial least squares; therefore, the variance in the measurement noise is often assumed to be zero for the Kalman filter-partial least square calibration model, which affects the stability of the model. In this study, the measured input and output data were used effectively, and the gamma test method for estimating the measurement noise variance was used to improve the stability of the Kalman filter-partial least square calibration model. First, an accurate estimation of the measurement noise variance was obtained, and accurate modeling was then performed using Kalman filter-partial least squares. Finally, 600 abandoned drilling fluid samples were used to confirm the validity of the proposed method. The Kalman filter-partial least square and gamma test-Kalman filter-partial least square methods are compared. Testing of external samples 401–600 demonstrated that the stability of the Kalman filter-partial least square model decreased. The root mean square error of the prediction of the Kalman filter-partial least square model was 27.135, which was worse than that of the gamma test-Kalman filter-partial least square model (20.307). The validation results show that the proposed method has better stability in tracking the evolution of the NIR spectrometer’s measurement state. 相似文献
135.
Carbon dioxide fixation by microalgae photosynthesis using actual flue gas discharged from a boiler 总被引:2,自引:0,他引:2
Matsumoto Hiroyo Shioji Norio Hamasaki Akihiro Ikuta Yoshiaki Fukuda Yoshinori Sato Minoru Endo Noriyoshi Tsukamoto Toshiaki 《Applied biochemistry and biotechnology》1995,(1):681-692
To mitigate CO2 discharged from thermal power plants, studies on CO2 fixation by the photosynthesis of microalgae using actual exhaust gas have been carried out. The results are as follows.
相似文献
1. | A method is proposed for evaluating the maximum photosynthesis rate in the raceway cultivator using only the algal physical properties; |
2. | Outdoor cultivation tests taking actual flue gas were performed with no trouble or break throughout 1 yr using the strain collected in the test; |
3. | The produced microalgae is effective as solid fuel; and |
4. | The feasibility studies of this system were performed. The system required large land area, but the area is smaller than that required for other biomass systems, such as tree farms. |
136.
Acetylcholinesterase was immobilised on magnetic particles and integrated in a flow-injection system via a magnetic reactor. Enzyme activity was determined amperometrically using acetylthiocholine chloride as enzyme substrate. This system was applied to enzyme inhibition tests. Inhibition constants and lower detection limits were determined for carbofuran, paraoxon, malaoxon and paraoxon-methyl. The resulting data were compared to those obtained with a photometric test, i.e. the determination of thiocholine via its reaction with the Ellman's reagent 5,5'-dithio-bis-2-nitrobenzoic acid using the same flow system. As they correlated well to those reported for the native enzyme the flow-injection analysis device can be applied to automated determination and characterisation of enzyme inhibitors. 相似文献
137.
选用二乙胺、三乙胺、正丙胺、异丙胺、正丁胺和异丁胺的硝酸盐作为气相色谱固定相,测得它们的使用温度范围均超过100℃。上述液体有机盐对具有大偶极矩分子化合物或具有氢键成键能力的化合物(如醇类)有良好的选择性,特别对醇类异构体的分离效果更佳;对酮类及单官能团取代苯的分离效果更令人满意,但对烃类不适用。 相似文献
138.
Bei Han Jing Long Liu Yi Huan Peng Li Qi Wu Zi Yun Lin Zhu Fang Shen Da Li Yin Hai Hong Huang 《中国化学快报》2012,23(3):297-300
Thirteen thiomorpholine-bearing compounds were designed and synthesized as dipeptidyl peptidase IV(DPP-IV) inhibitors, with natural and non-natural L-amino acids as the starting materials.Their structures were characterized by 1H NMR,13C NMR and HR-MS.The target compounds were screened for the DPP-IV inhibition,and the preliminary SAR result was obtained.Particularly, compounds 4c,4d and 4f with good DPP-IV inhibition in vitro were further evaluated through a mouse oral glucose tolerance test (OGTT).The preliminary result showed the potential value for further studies on those thiomorpholine-bearing compounds as DPP-IV inhibitors. 相似文献
139.
超临界流体萃取仪器的研制 总被引:1,自引:1,他引:1
本文报道了以国产原配件为基础,成功地研制了分析规模的超临界流体萃取仪器、并对仪器性能进行了全面考察,仪器性能稳定,重现性良好(RSD<3.1%),定量线性关系可靠,可满足定量萃取的要求。 相似文献
140.
在应用t、F检验时,要严格地区分方差齐性与方差非齐性两种不同的情况。在两种不同的情况下,计算总方差与自由度所用的公式是不同的。 相似文献