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排序方式: 共有374条查询结果,搜索用时 15 毫秒
91.
Yongjun Liu Nur Fadhilah Ibrahim 《Journal of Computational and Applied Mathematics》2010,235(1):286-292
In this paper we propose an iterative method to calculate the largest eigenvalue of a nonnegative tensor. We prove this method converges for any irreducible nonnegative tensor. We also apply this method to study the positive definiteness of a multivariate form. 相似文献
92.
A capillary electrophoresis method for the separation of high-molecular-mass heparin oligosaccharides compatible with mass spectral detection was developed. Structurally defined heparin oligosaccharides ranging in size from tetrasaccharide to tetradecasaccharide were used to optimize the conditions. Applying normal and reversed polarity modes, these oligosaccharides were separated by CE under various conditions. Ammonium hydrogencarbonate (30 mM at pH 8.50) used as the running electrolyte system gave good separation efficiency and resolution in the normal polarity mode. Application of this method to the separation of complicated heparin oligosaccharide mixtures required the addition of electrolyte additives. Ammonium hydrogencarbonate (30 mM), containing triethylamine (10 mM), was useful for the separation of complex oligosaccharide mixtures. Run-to-run and day-to-day precision and limits of detection were established for these separations. 相似文献
93.
Fermentation monitoring using multisensor systems: feasibility study of the electronic tongue 总被引:2,自引:0,他引:2
Esbensen K Kirsanov D Legin A Rudnitskaya A Mortensen J Pedersen J Vognsen L Makarychev-Mikhailov S Vlasov Y 《Analytical and bioanalytical chemistry》2004,378(2):391-395
The electronic tongue based on an array of 30 non-specific potentiometric chemical sensors has been applied to qualitative and quantitative monitoring of a batch fermentation process of starting culture for light cheese production. Process control charts were built by using PLS regression and data from fermentations run under normal operating conditions. Control charts allow discrimination of samples from fermentation batches run under abnormal operating conditions from normal ones at as early as 30–50% of fully evolved fermentations. The capability of the electronic tongue to quantify concentrations of important organic acids (citric, lactic and orotic) in the present type of fermentation media was demonstrated. Average prediction errors were assessed in the range 5–13% based on test set validation. Correlation between peptide profiles determined using HPLC and the electronic tongue output was also established. The electronic tongue was demonstrated to be a promising tool for fermentation process monitoring and quantitative analysis of growth media.http://www.electronictongue.com 相似文献
94.
Rinda Hedwig Wahyu Setia Budi Syahrun Nur Abdulmadjid Marincan Pardede Maria Margaretha Suliyanti Tjung Jie Lie Davy Putra Kurniawan Koo Hendrik Kurniawan Kiichiro Kagawa May On Tjia 《Spectrochimica Acta Part B: Atomic Spectroscopy》2006,61(12):1285-1293
The applicability of spectrochemical analysis for liquid and powder samples of minute amount in the form of thin film was investigated using ultraviolet Nd-YAG laser (355 nm) and low-pressure ambient air. A variety of organic samples such as commercial black ink usually used for stamp pad, ginseng extract, human blood, liquid milk and ginseng powder was prepared as film deposited on the surface of an appropriate hard substrate such as copper plate or glass slide. It was demonstrated that in all cases studied, good quality spectra were obtained with very low background and free from undesirable contamination by the substrate elements, featuring ppm or even sub-ppm sensitivity and worthy of application for quantitative analysis of organic samples. The proper preparation of the films was found to be crucial in achieving the high quality spectra. It was further shown that much inferior results were obtained when the atmospheric-pressure (101 kPa) operating condition of laser-induced breakdown spectroscopy or the fundamental wavelength of the Nd-YAG laser was employed due to the excessive or improper laser ablation process. 相似文献
95.
The metal binding properties of peptides corresponding to metal-binding sites spanning regions that normally function as linkers in tandem arrays of metal-binding domain-containing proteins were examined. For a peptide with two His residues from one TFIIIA-like zinc finger domain, a canonical TFIIIA-like linker, and two Cys residues from an adjacent zinc domain, the dissociation constant for the 1:1 peptide to cobalt(II) was found to be 15 +/- 10 microM, compared with 60 nM for the corresponding zinc finger domains themselves. Peptides overlapping two sets of metal-binding domains from human TRAF (tumor necrosis factor receptor-associated factor) proteins were examined. In one case, the affinity of the presumed metal-binding domain and that for the linker region were comparable, while in the second case, the affinity of the linker peptide was higher than that for the corresponding presumed metal-binding domain peptide. These studies revealed that cobalt(II) affinities in the micromolar range can occur even for peptides that do not correspond to natural zinc-binding domains and that the degree of distinction between authentic metal-binding domains and the corresponding linker-spanning peptides may be modest, at least for single domain peptide models. 相似文献
96.
97.
We clarify Bohrs interpretation of quantum mechanics by demonstrating the central role played by his thesis that quantum theory is a rational generalization of classical mechanics. This thesis is essential for an adequate understanding of his insistence on the indispensability of classical concepts, his account of how the quantum formalism gets its meaning, and his belief that hidden variable interpretations are impossible. 相似文献
98.
Mokashi Imran Khan Sher Afghan Abdullah Nur Azam Bin Azami Muhammad Hanafi Afzal Asif 《Journal of Thermal Analysis and Calorimetry》2020,141(6):2555-2571
Journal of Thermal Analysis and Calorimetry - The use of Li-ion battery in electric vehicles is becoming extensive in the modern-day world owing to their high energy density and longer life. But... 相似文献
99.
100.