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41.
The present review covers reports discussing potential applications of the specificity of Raman techniques in the advancement of digital farming, in line with an assumption of yield maximisation with minimum environmental impact of agriculture. Raman is an optical spectroscopy method which can be used to perform immediate, label-free detection and quantification of key compounds without destroying the sample. The authors particularly focused on the reports discussing the use of Raman spectroscopy in monitoring the physiological status of plants, assessing crop maturity and quality, plant pathology and ripening, and identifying plant species and their varieties. In recent years, research reports have presented evidence confirming the effectiveness of Raman spectroscopy in identifying biotic and abiotic stresses in plants as well as in phenotyping and digital selection of plants in farming. Raman techniques used in precision agriculture can significantly improve capacities for farming management, crop quality assessment, as well as biological and chemical contaminant detection, thereby contributing to food safety as well as the productivity and profitability of agriculture. This review aims to increase the awareness of the growing potential of Raman spectroscopy in agriculture among plant breeders, geneticists, farmers and engineers. 相似文献
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43.
T. Kupka J. G. Małecki P. Lodowski M. Jaworska J. O. Dzięgielewski 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):505-506
Abstract NMR, IR and semi empirical Molecular Orbital PM3 studies on selected β-lactam antibiotics are reported. The role of sulfur in β-lactam antibiotics is discussed. 相似文献
44.
Teobald Kupka Michał Stachów Jakub Kaminsky Stephan P. A. Sauer 《Magnetic resonance in chemistry : MRC》2013,51(8):482-489
A linear correlation between isotropic nuclear magnetic shielding constants for seven model molecules (CH2O, H2O, HF, F2, HCN, SiH4 and H2S) calculated with 37 methods (34 density functionals, RHF, MP2 and CCSD(T)), with affordable pcS‐2 basis set and corresponding complete basis set results, estimated from calculations with the family of polarization‐consistent pcS‐n basis sets is reported. This dependence was also supported by inspection of profiles of deviation between CBS estimated nuclear shieldings and shieldings obtained with the significantly smaller basis sets pcS‐2 and aug‐cc‐pVTZ‐J for the selected set of 37 calculation methods. It was possible to formulate a practical approach of estimating the values of isotropic nuclear magnetic shielding constants at the CCSD(T)/CBS and MP2/CBS levels from affordable CCSD(T)/pcS‐2, MP2/pcS‐2 and DFT/CBS calculations with pcS‐n basis sets. The proposed method leads to a fairly accurate estimation of nuclear magnetic shieldings and considerable saving of computational efforts. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
45.
Abstract 2,4,6-Tri-O-benzyl-D-galactal (1) was transformed into a 1-oxacephem skeleton. The sequence of reaction involved: [2+2]cycloaddition, N-alkylation, glycolic cleavage of the vic-diol grouping, reduction of dialdehyde and cyclization to the title skeleton. 相似文献
46.
Teresa Olszewska Maria J. Milewska Maria Gdaniec Tadeusz Połoński 《Tetrahedron: Asymmetry》2012,23(3-4):278-283
The crystal structures of several bicyclic N-nitrosamines indicate that they crystallize in the chiral (Sohncke) space group P212121 as conglomerates. This allows the resolution of these compounds by manual picking of the enantiomorphous crystals. The optical activity of the single crystals was confirmed by their CD spectra taken in KBr disks. The absolute configurations of the title nitrosamines were assigned by crystallographic measurements and by a comparison of their CD spectra with those of a reference compound resolved by classical methods. The observed Cotton effect signs, corresponding to the n–π1 transition, were correlated with the helicity of the inherently chiral nitrosamine chromophore. 相似文献
47.
Radosław Bonikowski Józef Kula Anna Bujacz Anna Wajs-Bonikowska Małgorzata Zakłos-Szyda Stanisław Wysocki 《Tetrahedron: Asymmetry》2012,23(14):1038-1045
Ten enantiomerically pure hydroindene-derived compounds obtained by the transformation of (+)-carotol, the main constituent of carrot seed essential oil, were examined for their ability to inhibit the growth of myeloid leukaemia (HL-60) cancer cell lines. All compounds showed significant activity, which was comparable to the most active volatile organic compounds, such as trans–trans-farnesol, citral and nerolidol. Based on the bioactivity and molecular modelling, a 3D QSAR pharmacophore model was generated. 相似文献
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49.
R. Göttgens J. M. Kohli P. Sixel U. Gensch H. Vogt Y. Goldschmidt-Clermont D. R. O. Morrison R. T. Ross S. Squarcia J. Chwastowski M. W. Krasny L. Suszycki W. Zielinski P. Girtler D. Kuhn K. W. J. Barnham P. R. S. Wright M. Zomorrodian D. I. Patalakha A. M. Moissev J. MacNaughton F. Mandl M. Markytan J. Mittendorfer M. Bardadin-Otwinowska A. Jachołkowska M. Szczekowski 《Zeitschrift fur Physik C Particles and Fields》1983,19(4):283-290
The inclusive proton diffraction dissociation cross sections in 16, 32, and 110 GeV/cK ? p interactions are determined from the spike nearx=1 in the inclusive negative particle spectra and are compared to those obtained inK?p interactions using other selection methods at various energies. The same procedure is applied to events containing aV 0 in order to obtain the cross section for diffractive \(s\bar s\) production. While the total cross section for proton diffraction is found to be approximately constant in the energy range studied here, proton diffraction yielding an \(s\bar s - pair\) is found to increase significantly. In particular it is almost constant at 85 μb forΛ 0 and Σ production but for \(NK\bar K\) it rises from zero at 16 GeV.c to about 200 μb at 110 GeV/c. From the result for \(s\bar s\) diffractive production an estimate for the \(c\bar c\) diffractive production cross section of approximately 1–10 μb at 110 GeV/c is obtained. 相似文献
50.
B. Niczyporuk Z. Jakubowski T. Zełudziewicz G. Folger B. Lurz H. Vogel U. Volland H. Wegener J. K. Bienlein R. Graumann H. -J. Trost M. Schmitz F. H. Heimlich R. Nernst A. Schwarz U. Strohbusch P. Zschorsch K. W. Chen A. C. König D. J. Schotanus M. Coles A. Engler R. W. Kraemer D. Marlow F. Messing C. Rippich S. Youssef A. Fridman G. Alexander A. Av-Shalom G. Bella J. Grunhaus W. Langguth M. Scheer LENA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1983,17(3):197-202
A search for the decays γ→ρπ, γ→J/ψX and γ→γa (whereX is undetermined and a is an axion) has been completed using the LENA detector at the DORIS storage ring. No evidence for any of these processes was found. For these decay modes we set branching fraction upper limits (90% C.L.) of 2.1×10?3, 2.0×10?2 and 9.1×10?4, respectively. 相似文献