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51.
52.
Shozo Tamaki 《Mikrochimica acta》1985,87(1-2):1-13
Summary
Improvement in Quantitative Correction in SIMS Using Saha-Eggert Equation
A quantitative conversion of the secondary-ion current intensities into the elemental concentrations using the Saha-Eggert ionization equation was tried with a 78Ni-18Cr-1Ti-1Fe-1Cu-1Zr (each in at %) alloy. Improvements were made on the best-fit search of fitting parameters (T andN
e). It proved to be important for the success in the conversion (1) to use the secondary-ion intensities from the sample in oxygen gas of >1.5×10–3 Pa, (2) to add the molecularion intensities to those of mother atomic ions even when the former are small and (3) to search for the fitting parameters considering the relative errors of concentrations not only for the internal standards but for as many elements as possible. With these procedures the largest error of elemental concentration could be reduced to 22% (Ar+ bombardment), 31% (O2
+ bombardment) and 19% (N2
+bombardment).A part of this paper was presented at the 4th International Conference on Secondary Ion Mass Spectrometry, Osaka, November 1983. 相似文献
53.
Komaki Shozo Tsukamoto Katsutoshi Okada Minoru Ishida Tomoaki 《Optical and Quantum Electronics》1998,30(11-12):1079-1088
Mobile communication systems such as cellular radio and PHS are rapidly penetrating into our real life, and have gained many subscriber numbers. User demands will be growing to higher data rates that support multimedia mobile computing demands, such as graphics and motion pictures. These demands require more band width and/or spectrum utilization efficiency enhancement, and optically fed communication systems are considered to be one of the most powerful solutions. In this paper, the roles, technologies and application examples of optically fed communication systems are described. In the final part, prospects for systems and requirements for photonic devices are mentioned. 相似文献
54.
55.
2-[2-(3,5-Dibrornopyridyl)azo]-5-dimethyIam;nobenzoic acid (3,5-diBr-PAMB) has been synthesized and its potential for the spectrophotometric determination of metals studied. It reacts sensitively with nickel, cobalt, iron and copper, and is particularly useful for nickel. The apparent molar absorptivity in chloroform is 1.50 × 105 l mol-1 cm-1 and the Sandell sensitivity is 0.4 ng Ni cm-2. Nickel reacts with 3.5-diBr-PAMB at pH 4–10; at pH 4–7 the complex can be extracted into chloroform to give a stable purple solution. The optimal calibration range is 0.04–0.4 ppm Ni. Only Cu, Co, Fe, Pd and V interfere seriously but Pd, Cu and V can be masked by thiourea. 相似文献
56.
Iwao Amada Minoru Yamaji Masami Sase Haruo Shizuka Takuji Shimokage Shozo Tero-Kubota 《Research on Chemical Intermediates》1998,24(1):81-104
Investigations using CIDEP techniques showed that an H-atom abstraction from phenol and the electron transfer from 1,2,4,5-tetramethoxybenzene
to photoexcited 2,3-dibromo-1,4-naphthoquinone (DBNQ) and 2,3-dichloro-1,4-naphthoquinone (DCNQ) in the polar media originated
from their triplet states. Nanosecond laser photolysis at 355 nm was carried out to determine the absorption spectra and coefficients
of the corresponding triplet states, semiquinone, and anion radicals for a quantitative investigation of the mechanisms involved
in the H-atom abstraction and the electron transfer. The steric hindrance of the substituted groups was indifferent to H-atom
abstraction. The electronic structures of triplet DBNQ and DCNQ at 295 K were both revealed to be the mixed states of 3(n,π*) with a 3(π,π*) character. 相似文献
57.
Shozo Shibata 《Angewandte Chemie (International ed. in English)》1976,15(11):673-679
At present, dual-wavelength spectrophotometry is probably the least well known of the techniques of absorption spectrophotometry. However, recent improvements in application techniques have shown that for various organic and inorganic materials dual-wavelength spectrophotometry can provide higher sensitivity and selectivity than conventional spectrophotometry. This article reviews the principles and scope of dual-wavelength spectrophotometry, including derivative absorption spectrophotometry, in the hope that these techniques may be adopted more frequently in the future for resolving many analytical problems. 相似文献
58.
Jiang KJ Masaki N Xia JB Noda S Yanagida S 《Chemical communications (Cambridge, England)》2006,(23):2460-2462
A hydrophobic and 2-thiophen-2-yl-vinyl-conjugated ruthenium complex, cis-Ru(dhtbpy)(dcbpy)(NCS)2 [dhtbpy = 4,4'-di(hexylthienylvinyl)-2,2'-bipyridyl; dcbpy = 4,4'-dicarboxy-2,2'-bipyridyl], was newly designed, synthesized and applied successfully to sensitization of nanocrystalline TiO2-based solar cells, giving a conversion efficiency of 9.5% under irradiation with AM 1.5 solar light. 相似文献
59.
Nagano Y Liu JG Naruta Y Ikoma T Tero-Kubota S Kitagawa T 《Journal of the American Chemical Society》2006,128(45):14560-14570
Physicochemical properties of the covalently cross-linked tyrosine-histidine-Cu(B) (Tyr-His-Cu(B)) unit, which is a minimal model complex [M(II)-BIAIPBr]Br (M = Cu(II), Zn(II)) for the Cu(B) site of cytochrome c oxidase, were investigated with steady-state and transient absorption measurements, UV resonance Raman (UVRR) spectroscopy, X-band continuous-wave electron paramagnetic resonance (EPR) spectroscopy, and DFT calculations. The pH dependency of the absorption spectra reveals that the pK(a) of the phenolic hydroxyl is ca. 10 for the Cu(II) model complex (Cu(II)-BIAIP) in the ground state, which is similar to that of p-cresol (tyrosine), contrary to expectations. The bond between Cu(II) and nitrogen of cross-linked imidazole cleaves at pH 4.9. We have successfully obtained UVRR spectra of the phenoxyl radical form of BIAIPs and have assigned bands based on the previously reported isotope shifts of Im-Ph (2-(1-imidazoyl)-4-methylphenol) (Aki, M.; Ogura, T.; Naruta, Y.; Le, T. H.; Sato, T.; Kitagawa, T. J. Phys. Chem. A 2002, 106, 3436-3444) in combination with DFT calculations. The upshifts of the phenoxyl vibrational frequencies for 8a (C-C stretching), 7a' (C-O stretching), and 19a, and the Raman-intensity enhancements of 19b, 8b, and 14 modes indicate that UVRR spectra are highly sensitive to imidazole-phenol covalent linkage. Both transient absorption measurements and EPR spectra suggest that the Tyr-His-Cu(B) unit has only a minor effect on the electronic structure of the phenoxyl radical form, although our experimental results appear to indicate that the cross-linked Tyr radical exhibits no EPR. The role of the Tyr-His-Cu(B) unit in the enzyme is discussed in terms of the obtained spectroscopic parameters of the model complex. 相似文献
60.
Watanabe E Miyake S Baba K Eun H Endo S 《Analytical and bioanalytical chemistry》2006,386(5):1441-1448
This work describes the fundamental ability of a commercial ELISA to determine acetamiprid and the application of the ELISA
to residue analysis in fruit and vegetable samples. The ELISA exhibited satisfactory sensitivity (I
50 0.6 ng/g; limit of detection 0.053 ng/g) and a high selectivity for acetamiprid versus other neonicotinoid analogs (thiacloprid
amide). Methanol, which influenced the sensitivity of the ELISA the least, was selected as the extractant for the ELISA analysis.
Simple dilution of sample extracts with water eliminated matrix interferences. Average recoveries from the acetamiprid-spiked
agricultural samples were >95% using a simple extraction method. Analytical results obtained from the ELISA were comparable
to those obtained from the reference HPLC method (r>0.99). The ELISA applied to the residue analysis of acetamiprid in agricultural products is a rapid, simple, and cost-effective
method, and could be successfully applied to the detection of acetamiprid before the distribution of produce. 相似文献