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1.

In this work, four types of data mining methods, namely adaptive neuro-fuzzy inference system, artificial neural network—multilayer perceptron algorithm (ANN-MLP), artificial neural network—radial basis function algorithm (ANN-RBF), and group method of data handling (GMDH) have been used to predict the enhancement of the relative thermal conductivity of a wide range of nanofluids with different base fluids and nanoparticles. The total number of experimental data used in this work is 483 from 18 different nanofluids. The input parameters are thermal conductivity of base fluid and nanoparticles, volume fraction percent, the average size of nanoparticles, and temperature. Although the results showed that all four models are in relatively good agreement with experimental data, the ANFIS method is the best. The average absolute relative deviations (AARD%) between the experimental data and those of obtained using ANFIS, ANN-MLP, ANN-RBF, and GMDH methods were calculated as 2.7, 2.8, 4.2, and 4.3, respectively, for the test sets and as 1.1, 2.4, 3.9, and 4.5, respectively, for the training sets. Comparison between the predictions of the proposed ANN-MLP, ANN-RBF, ANFIS, and GMDH models and those predicted by traditional models, namely Maxwell and Bruggeman models showed that much better agreements can be obtained using the four models especially ANFIS model. Accordingly, the ANFIS method can able us to predict the relative thermal conductivity of new nanofluids in different conditions with good accuracy.

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2.
Analytical strategies dealing with bioactive phenols in plants and foods are reviewed. These depend on the purpose of the analysis which may be classified as studies where the principal purpose is biological screening, phytochemical and/or chemical screening. Nevertheless, extraction of the phenol from the sample matrix is common and methods of achieving a suitable extract are assessed. Advances in the separation sciences and spectrometry are exploited for identification and quantification of isolated phenols. The various procedures are summarized and some typical “case studies” are presented. Two important areas are introduced briefly. Thus, plant phenols are reactive species and their ultimate fate has been relatively neglected. Studies of bioactive compounds generate a considerable volume of data making data handling and informatics important topics that warrant a separate review.  相似文献   

3.
A number of multivariable statistical techniques have been prepared for handling programs or mass spectra. The more widely used methods are reviewed and their application, the microbiological data set compared. The results are drawn together to formulate a XXXXX data handling rationale capable of processing a variety of pyrolyses applications.  相似文献   

4.
5.
A method has been developed and validated for the quantification of ramoplanin, a 2554 Da peptide antibiotic, in human dried blood spots using high‐performance liquid chromatography with tandem mass spectrometric detection. The validation data meet FDA acceptance criteria for bioanalytical assays and cover the quantification of ramoplanin over the range 10–5000 ng/mL. The assay determines ramoplanin at the same lower limit of quantification as conventional liquid sample methods. Dried blood spot analysis provides an approach for quantification of peptide therapeutics and delivers significant benefits for sample collection and handling and also sample cleanup over conventional plasma and serum assays. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

6.
High-performance liquid chromatography (HPLC) of heparins was carried out with on-line photodiode-array detection. Average molecular weights and molecular weight distribution were calculated using computer data acquisition and handling; size-exclusion chromatography was performed using different selective microparticulate columns and narrow molecular weight distribution heparin standards for calibration; heparin peak purity was investigated using several methods for evaluation. Additional UV-absorbing compounds present in heparin preparations were characterized and quantitated by reversed-phase HPLC. These methods are useful for the analysis of the molecular weight distribution and peak purity of heparins and for the determination of additional drugs, additives or impurities.  相似文献   

7.
In this paper we report using a parallel, four-channel HPLC/MUX/MS purification system, the Purification Factory, to purify thousands of compounds destined for high-throughput screening in a single month. The maximum sample throughput during this 20-workday month was 704 samples/day. Since this purification throughput exceeded the postpurification sample and data handling capabilities provided by commercial solutions, a custom-integrated solution was designed to address these shortcomings. In this paper we detail the key improvements in automation, solvent handling, and sample handling logistics implemented to sustain a mean throughput of 528 samples/day over a multimonth time period.  相似文献   

8.
Abstract

Techniques for sample preparation and handling of serum prior to analysis for nucleoside and bases were evaluated. Efficiency data are reported for the trichloracetic acid (TCA), ammonium sulfate, ultrafiltration and pre-column concentration sample prep-atation techniques. Maximum recoveries for most of the compounds were obtained using the ultrafiltration, ammonium sulfate and pre-column concentration techniques. Poorer recovery was observed using the TCA/Freon-amine methods. Theophylline and tryptophan exhibited pH dependent recoveries using the ultrafiltration, ammonium sulfate and pre-column techniques.  相似文献   

9.
A series of coumarin-3-yl substituted unsymmetrical ureas were synthesized by the reaction of 3-coumarin isocyanate, which was prepared from 3-coumarinyl azide by Curtius rearrangement, with various aromatic amines, 2-amino-5-phenyl-1,3,4-thiadiazole, and 2-amino-5-aryloxymethylene-1,3,4-thiadiazoles under microwave irradiation. Compared to conventional methods, this synthesis has the advantages of mild reaction conditions, easy handling, and high yields. The products have been characterized by analytical and spectral (IR and 1H NMR) data.  相似文献   

10.
Metrologically based measuring procedures and evaluation methods are recommended as guidance for practical temperature, heat and heat flow rate calibration of DSC instruments which are largely independent of instrumental, test and sample parameters. The relevant terms are defined, the measuring procedures and evaluation methods described, calibration materials and their characteristic data stated and guidance for the sample handling provided. Reference is made to three extended papers on calibration. The recommendations were developed by the working group Calibration of Scanning Calorimeters of the German Society of Thermal Analysis (GEFTA).Recommendation of the working group Calibration of scanning calorimeters of the Gesellschaft für Thermische Analyse e.V. (GEFTA)  相似文献   

11.
This paper gives an overview of the advantages and associated caveats of the most common sample handling methods in surface-sensitive chemical and biological sensing. We summarize the basic theoretical and practical considerations one faces when designing and assembling the fluidic part of the sensor devices. The influence of analyte size, the use of closed and flow-through cuvettes, the importance of flow rate, tubing length and diameter, bubble traps, pressure-driven pumping, cuvette dead volumes, and sample injection systems are all discussed. Typical application areas of particular arrangements are also highlighted, such as the monitoring of cellular adhesion, biomolecule adsorption–desorption and ligand–receptor affinity binding. Our work is a practical review in the sense that for every sample handling arrangement considered we present our own experimental data and critically review our experience with the given arrangement. In the experimental part we focus on sample handling in optical waveguide lightmode spectroscopy (OWLS) measurements, but the present study is equally applicable for other biosensing technologies in which an analyte in solution is captured at a surface and its presence is monitored. Explicit attention is given to features that are expected to play an increasingly decisive role in determining the reliability of (bio)chemical sensing measurements, such as analyte transport to the sensor surface; the distorting influence of dead volumes in the fluidic system; and the appropriate sample handling of cell suspensions (e.g. their quasi-simultaneous deposition). At the appropriate places, biological aspects closely related to fluidics (e.g. cellular mechanotransduction, competitive adsorption, blood flow in veins) are also discussed, particularly with regard to their models used in biosensing.  相似文献   

12.
Current research in the field of real-time monitoring of water quality is reviewed from an Australian perspective. The desirable features of continuous monitoring instruments and progress in developing multi-parameter real-time instruments are considered first. Then Australian R&D in the three main areas involved in developing a complete instrument are considered; these are sample preparation and handling, new sensors and sensing chemistry, and finally data capture, processing and display. The review identifies five areas where developments are needed: new methods for handling and processing ‘real’ (i.e. ‘dirty’ and heterogeneous) samples; the development of new sensors to provide more detailed information on particular forms (e.g. bioavailable) of contaminants; new sensors for detecting and quantifying the presence of low concentrations of toxic organic compounds in natural waters; new real-time methods for assessing the microbial quality of waters; and greater use of chemometrics in processing the signals obtained from complex sample matrices.  相似文献   

13.
Yoshimori T 《Talanta》1975,22(10-11):827-835
A review is given of the methods of drying standard reference materials, and handling them after drying. The status of the Faraday as an international reference standard for titrimetric analysis is also discussed.  相似文献   

14.
Radiochemical quality control using high performance high pressure liquid chromatography and, to some extent, gas chromatography is described for a variety of carrier-free11C-,18F-and123I-labelled compounds and radiopharmaceuticals. The particular problems associated with the handling of carrier-free compounds labelled with short-lived radionuclides are outlined, and chromatographic data are given for the separation and purification of such products.  相似文献   

15.
The signal handling requirements for graphite furnace atomic absorption are much more demanding than those for flame atomic absorption. Graphite furnace signals change rapidly, background levels are higher, and signal interpretation needs are more extensive.We have identified a number of signal generation and processing factors that are important for success in graphite furnace analyses. These include: use of the transverse, a.c. Zeeman technique with the magnet on the analyte for background correction; production of a series of signal integrals at line frequency to accurately represent the shape of the furnace peak; use of interpolation techniques to better correct for rapidly changing background levels; use of integrated peak absorbance (A.s) signals rather than peak height absorbance for quantitative measurements; use of baseline correction to improve the accuracy of integrated peak absorbance signals; and use of graphical techniques to facilitate data interpretation and methods development.Examples are presented that illustrate the contribution of these factors to precision and detection limit performance. It is possible to improve detection limits over those previously reported by choosing appropriate signal handling parameters.  相似文献   

16.
Currently laboratory automation is a rapidly growing field of interest in chemical process research and development. The idea of using automated and parallel methods for the optimization of chemical processes was initiated by the extensive implementation of combinatorial techniques in medicinal chemistry. The techniques applied involve all methods and concepts aimed at dramatically increasing the output of research by extensive use of automation, parallelization and miniaturization, fast analysis, advanced data handling and by efficient automated planning, scheduling and tracking. In this paper, the “Combi” or high‐throughput experimentation approach consists of the integration of parallel experimentation with four key modeling and simulation methodologies, modeling, multivariate statistics, statistical design of experimentation and empirical model generation.

Integrated automated liquid and solid handling.  相似文献   


17.
This report provides an introduction to the principal methods of extraction with supercritical gases, illustrated by the processing of some natural products with carbon dioxide. The combination of pressure and temperature as process parameters makes it possible to vary the solvent power of the medium within certain ranges as desired without having to change the composition of the solvent, as would be necessary in conventional solvent extraction. The problem-free handling of carbon dioxide and also of the products obtained open up possibilities whose development has only just started.  相似文献   

18.
Recent years have seen an increased interest in DNA trace detection methods involved in many areas of bioanalytical research, such as quantitation of genetically modified (GM) ingredients in food products. There is little in the way of standardisation of data handling from these methods, and the data generated needs to be analysed appropriately if the results are to be interpreted correctly. This paper describes particular aspects of real-time PCR trace detection methods in order to increase the understanding of data generated using this bioanalytical technique. Using the specific example of GM soya detection and quantitation, it focuses on the production of calibration curves based on the mean and individual data values, the interpretation of correlation coefficients, regression techniques, and discusses suitable data analysis arising from simple and more complex experimental designs following transformation. By using the approaches outlined in this paper, more accurate analysis of data from real-time PCR and GM trace detection methods could be achieved.  相似文献   

19.
A graphical analysis to elucidate the order in catalyst is presented. This analysis uses a normalized time scale, t [cat]Tn, to adjust entire reaction profiles constructed with concentration data. The method is fast and simple to perform because it directly uses the concentration data, therefore avoiding the data handling that is usually required to extract rates. Compared to methods that use rates, the normalized time scale analysis requires fewer experiments and minimizes the effects of experimental errors by using information on the entire reaction profile.  相似文献   

20.
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