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排序方式: 共有315条查询结果,搜索用时 62 毫秒
1.
Stadnyk V. Yo. Shchepanskyi P. A. Rudysh M. Ya. Kogut Z. A. 《Journal of Applied Spectroscopy》2021,88(4):831-837
Journal of Applied Spectroscopy - The temperature dependence of the refractive indices of K2SO4 with copper impurity was investigated. It was found that introduction of the copper impurity leads to... 相似文献
2.
A signal registration strategy from micropatterned immunosensors that converts antigen-antibody binding reactions into electrochemical signals was demonstrated. An array-type micropatterned gold electrode on a silicon wafer was fabricated, containing two electrode geometries of rectangular (100 microm x 500 microm) and circular (r. 50 microm) types, exhibiting electrochemical characteristics of bulk and micro-electrodes, respectively. Ferritin was employed as a model analyte for immunosensing because it has an advantageous molecular structure for functionalization to the sensing interface, and is regarded as a general marker protein for tumors and cancer recurrence. With the fabricated and ferritin-functionalized immunosensors, biospecific interactions were performed with antiferritin antiserum and secondary antibody samples, followed by electrochemical signaling via an immunoprecipitation reaction by the label enzyme. Under the optimized affinity-surface construction steps and reaction conditions, both types of microfabricated electrodes exhibited well-defined calibration results as a function of the protein concentration in antiserum samples. Furthermore, circular-type micropatterned immunoelectrodes exhibited voltammetric characteristics of microelectrodes, which is advantageous in terms of sensor operation under a fixed potential and low signal drift during the signaling reaction compared with the bulk-type electrodes. The results support that the employed signaling method with the proposed immunosensor configuration is fit for sensor miniaturization and integration to future biomicrosystems. 相似文献
3.
Nahoko Yamaji Manabu Horikawa Hideo Naoki Terumi Nakajima 《Tetrahedron letters》2004,45(28):5371-5373
A novel polyamine toxin, named MG30, was isolated from the venom of the spider, Macrothele gigas, and its structure was elucidated by two-dimensional NMR and mass analysis. In addition, the enantioselective synthesis of MG30 was achieved to assign its absolute stereochemistry. 相似文献
4.
Yang Ju Yo Hirosawa Masumi Saka Hiroyuki Abé 《International Journal of Infrared and Millimeter Waves》2003,24(3):391-397
We developed a compact equipment working at 94 GHz to replace the commonly used network analyzer for nondestructive testing of materials. The compact equipment was designed to measure the variations in the amplitude and phase of the reflected signal from the material relative to a reference signal. A good accuracy of the amplitude and phase measurement of the equipment was obtained in the confirmative experiments. The distribution of a drop of water in a wood plate is clearly visible in the millimeter wave images obtained by the amplitude and phase measurement. 相似文献
5.
We give a brief overview of important results in several areas of sensitivity and stability analysis for nonlinear programming, focusing initially on qualitative characterizations (e.g., continuity, differentiability and convexity) of the optimal value function. Subsequent results concern quantitative measures, in particular optimal value and solution point parameter derivative calculations, algorithmic approximations, and bounds. Our treatment is far from exhaustive and concentrates on results that hold for smooth well-structured problems.Research supported by National Science Foundation Grant ECS-86-19859 and Grant N00014-89-J-1537 Office of Naval Research. 相似文献
6.
Dimitrakakis E Haberhauer-Troyer C Abe Y Ochsenkühn-Petropoulou M Rosenberg E 《Analytical and bioanalytical chemistry》2004,379(5-6):842-848
The use of solid-phase microextraction (SPME) with gas chromatography coupled to microwave-induced plasma atomic-emission detection (GC–MIP-AED) is described for selenite [Se(IV)] speciation. Aqueous standards were derivatised with sodium tetraethyl- or tetrapropylborate and extracted by SPME. Headspace extraction of the ethyl and propyl derivatives was studied. Relevant experimental conditions were optimised, including conditions for derivatisation and extraction and those of gas chromatographic analysis. The limits of detection achieved for headspace sampling of derivatised Se(IV) were in the low ng mL–1 range for both ethylation and propylation. When the method was applied to analysis of selenite in selenised yeast reference material results were in good agreement with the indicated values. 相似文献
7.
A method is presented for simultaneous separation of traces of toxic and essential elements from soils. The method is based on programmed vacuum-thermic extraction of the elements in an oxidation-reduction medium. Under optimal conditions of temperature and pressure Pb, Zn, Cd, Bi, Tl, As, Sb, Te, Mo, Hg and Re are distilled or sublimated in elementary state or as oxides. A simple quartz apparatus is proposed. The elements extracted from matrix are dissolved in nitric acid and determined by AAS or OES with ICP excitation. 相似文献
8.
H Yamazaki H Horikawa T Nishitani T Iwasaki K Nosaka H Tamaki 《Chemical & pharmaceutical bulletin》1992,40(1):102-108
2,2,-Disubstituted norbornenes (1, 2), 2,2-Disubstituted norbornane (3), 2,2,3-trisubstituted norbornenes (4, 5), oxanorbornenes (6) and azanorbornenes (7) were synthesized by the Diels-Alder reaction using alpha, beta-dehydroamino acids as a key step, and their antiulcer activities were examined. The oxazolidine derivative (1h) exhibited the most potent activities against several ulcer-models in rat. 相似文献
9.
Yo Ueda K
ichi Mori Keiki Kouno Tokihiro Nhya 《Journal of mass spectrometry : JMS》1976,11(10):1027-1036
The mass spectra of 30 sulfinamide derivatives (RSONHR', R' alkyl or p-XC6H4) are reported. Most of the spectra had peaks attributable to thermal decomposition products. For some compounds these were identified by pyrolysis under similar conditions to be: RSO2NHR', RSO2SR, RSSR and NH2R' (in all kinds of sulfinyl amides); RSNHR' (in the case of arylsulfinyl arylamides); RSO2C6H4NH2, RSOC6H4NH2 and RSC6H4NH2 (in the case of arylsulfinyl arylamides of the type of X = H) The mass spectra of the three thermally stable compounds showed that there are several kinds of common fragment ions. The mass spectra of the thermally labile compounds had two groups of ions; (i) characteristic fragment ions of the intact molecules and (ii) the molecular ions of the thermal decomposition products. It was concluded that the sulfinamides give the following ions after electron impact: [M]+, [M ? R]+, [M ? R + H]+, [M ? SO]+, [RS]+, [NHR']+, [NHR' + H]+, [RSO]+, [RSO + H]+, [R]+, [R + H]+, [R']+ and [M ? OH]+, and that the thermal decomposition products give the following ions: [RSO2SR]+, [RSSR]+, [M ? O]+, [M + O]+ and [RSOC6H4NH2]+. 相似文献
10.
Yo. Pelovski M. Petkova Iv. Dombalov G. Liptay 《Journal of Thermal Analysis and Calorimetry》1994,42(2-3):485-490
The ability of some siliconates to hydrophobize and modify the surface of different kinds of asbestos was studied. A 6 wt% aqueous solution of potassium methylsiliconate was used in various quantities. After treatment, the asbestos samples were analysed by IR-spectroscopy, TG-DTA and electron microscopy. Structural changes were found on the asbestos surface, including the appearance of chemical bonds. The studies revealed that the sorption and lyophilic properties of asbestos are lowered, these being the basic preconditions for its injurious action on health. 相似文献