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161.
Motivated by some investigations of Babbage and a method of solving certain functional equations arising in competition problems, we investigate a class of functional equations and prove a local existence and uniqueness theorem for them. The main tools of the proof are the Inverse Function Theorem and the Global Existence and Uniqueness Theorem. 相似文献
162.
By applying a method due to Saint Raymond, we prove the existence of infinitely many weak solutions for a quasilinear elliptic
partial differential equation, involving the p-Laplacian operator, coupled with a nonlinear boundary condition. Our main assumption is a suitable oscillatory behaviour
of the nonlinearity either at infinity or at zero. 相似文献
163.
Dr. Anna F. Staerz Marieke van Leeuwen Dr. Tatiana Priamushko Dr. Torben Saatkamp Dr. Balázs Endrődi Dr. Nina Plankensteiner Dr. Matias Jobbagy Sohrab Pahlavan Dr. Martijn J. W. Blom Dr. Csaba Janáky Dr. Serhiy Cherevko Dr. Philippe M. Vereecken 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(5):e202306503
164.
O. Varga 《Monatshefte für Mathematik》1941,50(1):165-175
Ohne Zusammenfassung 相似文献
165.
Eszter Takcs Borbla Gmes Fanni Szendrei Csaba Keszei Attila Barcsi Sndor Lenk Lszl Domjn Mria Mrtl Andrs Szkcs 《Molecules (Basel, Switzerland)》2022,27(19)
An enzyme-linked fluorescent immunoassay (ELFIA) method has been developed for the quantitative analytical determination of the herbicide active ingredient glyphosate in environmental matrices (surface water, soil, and plant tissues). Glyphosate, as a ubiquitous agricultural pollutant, is a xenobiotic substance with exposure in aquatic and terrestrial ecosystems due its extremely high worldwide application rate. The immunoassay developed in Project Aquafluosense is part of a fluorescence-based instrumentation setup for the in situ determination of several characteristic water quality parameters. The 96-well microplate-based competitive immunoassay method applies fluorescence signal detection in the concentration range of 0–100 ng/mL glyphosate. Application of the fluorescent signal provides a limit of detection of 0.09 ng/mL, which is 2.5-fold lower than that obtained with a visual absorbance signal. Beside the improved limit of detection, determination by fluorescence provided a wider and steeper dynamic range for glyphosate detection. No matrix effect appeared for the undiluted surface water samples, while plant tissues and soil samples required dilution rates of 1:10 and 1:100, respectively. No cross-reaction was determined with the main metabolite of glyphosate, N-aminomethylphosphonic acid, and related compounds. 相似文献
166.
167.
Nelson Torto Thomas Laurell Lo Gorton Gyrgy Marko Varga 《Journal of membrane science》1997,130(1-2):239-248
We report a study made on a 5 kDa molecular weight cut-off (MWCO) polysulfone membrane (SPS 4005) for use in microdialysis sampling of starch enzymatic hydrolysates on-line coupled to column liquid chromatography with integrated pulsed electrochemical detection. Membrane characteristics were evaluated by examining both the membrane and membrane support layer using a scanning electron microscope (SEM). This study was made so as to elucidate the mechanism or mode by which a membrane exposed to different bioprocess conditions is either fouled or destroyed. The correlation of extraction fraction data with SEM was a confirmatory test for the observed change in the membrane characteristics. Examinations were made after keeping the membrane in pure water for 5, 10 and 30 min at room temperature or after perfusing the membrane with pure water continuously at room temperature, 60 and 90°C for 24 h. Extraction fractions were evaluated at these temperatures to see applicability of the SPS 4005 membrane to high temperature bioprocesses. Scanning electron microscopy studies were also made on membranes used for sampling and sample clean-up during on-line monitoring of the hydrolysis of soluble starch (according to Zulkowsky) for 32 h, and the hydrolysis of wheat starch at room temperature, 60 and 90°C for 6 h. Non-specific/directed protein-membrane interactions were evaluated by sampling maltoheptaose with a microdialysis probe fitted with a 10 mm SPS 4005 membrane, before and after treatment with an enzyme solution of Termamyl (endo-1,4--
-glucan glucanohydrolase EC 3.2.1.78). 相似文献
168.
The concept of aG-function, introduced by Nowosad and Hoffman, gives an appropriate setting for many generalizations of the Gerschgorin Circle Theorem. In this paper, we extend our previous results for minimalG-functions to the partitioned matrix case. 相似文献
169.
Lewis E. Varga 《Journal of Combinatorial Theory, Series A》1985,40(2):435-438
We show that if a pairwise balanced design with λ = 1 has ν objects and block sizes between 2 and ν − 2, and it is not a symmetric balanced design, then each of its largest blocks has a nonempty intersection with at least ν other blocks 相似文献
170.