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91.
Designs, Codes and Cryptography - 相似文献
92.
Dr. Mathieu F. Chellat Luka Raguž Prof. Dr. Rainer Riedl 《Angewandte Chemie (International ed. in English)》2016,55(23):6600-6626
Finding strategies against the development of antibiotic resistance is a major global challenge for the life sciences community and for public health. The past decades have seen a dramatic worldwide increase in human‐pathogenic bacteria that are resistant to one or multiple antibiotics. More and more infections caused by resistant microorganisms fail to respond to conventional treatment, and in some cases, even last‐resort antibiotics have lost their power. In addition, industry pipelines for the development of novel antibiotics have run dry over the past decades. A recent world health day by the World Health Organization titled “Combat drug resistance: no action today means no cure tomorrow” triggered an increase in research activity, and several promising strategies have been developed to restore treatment options against infections by resistant bacterial pathogens. 相似文献
93.
Synthesis,Separation, and Characterization of Small and Highly Fluorescent Nitrogen‐Doped Carbon NanoDots
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Francesca Arcudi Luka Đorđević Prof. Maurizio Prato 《Angewandte Chemie (International ed. in English)》2016,55(6):2107-2112
A facile bottom‐up approach to carbon nanodots (CNDs) is reported, using a microwave‐assisted procedure under controlled conditions. The as‐prepared nitrogen‐doped CNDs (NCNDs) show narrow size‐distribution, abundant surface traps and functional groups, resulting in tunable fluorescent emission and excellent solubility in water. Moreover, we present a general method for the separation of NCNDs by low‐pressure size‐exclusion chromatography, leading to an even narrower size distribution, different surface composition, and optical properties. They display among the smallest size and the highest FLQYs reported so far. 13C‐enriched starting materials produced N13CNDs suitable for thorough NMR studies, which gave useful information on their molecular structure. Moreover, they can be easily functionalized and can be used as water‐soluble carriers. This work provides an avenue to size‐ and surface‐controllable and structurally defined NCNDs for applications in areas such as optoelectronics, biomedicine, and bioimaging. 相似文献
94.
Dr. Luka Đorđević Dr. Hiroaki Sai Dr. Yang Yang Dr. Nicholas A. Sather Dr. Liam C. Palmer Prof. Dr. Samuel I. Stupp 《Angewandte Chemie (International ed. in English)》2023,62(17):e202214997
Supramolecular polymerization of π-conjugated amphiphiles in water is an attractive approach to create functional nanostructures. Here, we report on the synthesis, optoelectronic and electrochemical properties, aqueous supramolecular polymerization, and conductivity of polycyclic aromatic dicarboximide amphiphiles. The chemical structure of the model perylene monoimide amphiphile was modified with heterocycles, essentially substituting one fused benzene ring with thiophene, pyridine or pyrrole rings. All the heterocycle-containing monomers investigated underwent supramolecular polymerization in water. Large changes to the monomeric molecular dipole moments led to nanostructures with low electrical conductivity due to diminished interactions. Although the substitution of benzene with thiophene did not notably change the monomer dipole moment, it led to crystalline nanoribbons with 20-fold higher electrical conductivity, due to enhanced dispersion interactions as a result of the presence of sulfur atoms. 相似文献
95.
Vesna Cerkvenik-Flajs Luka Mil?inski Lena Hodoš?ek Jan Antoni? 《Analytica chimica acta》2010,663(2):165-29
An analytical method has been developed for the simultaneous determination of the following endectocide drugs in milk: ivermectin, abamectin, doramectin, moxidectin, eprinomectin, emamectin and nemadectin. Samples were extracted with acetonitrile, purified with solid-phase extraction on a reversed phase C8, derivatised with N-methylimidazole, trifluoroacetic anhydride and acetic acid to a stable fluorescent derivative, and were further analysed by gradient high performance liquid chromatography (HPLC) on an endcapped reversed phase Supelcosil LC-8-DB. The derivatisation step was mathematically optimised and the method was validated according to the requirements of Commission Decision 2002/657/EC, using fortified raw bovine milk. Mean recovery was between 78 and 98%. The repeatability (CVr) and within-laboratory reproducibility (CVW) ranged from 4.6 to 13.4% and from 6.6 to 14.5%, respectively. Decision limits (CCα) for analytes with MRL values, namely eprinomectin and moxidectin, were determined to be 24.8 and 50.6 μg kg−1, respectively. CCα values for unauthorised endectocides ranged from 0.1 to 0.2 μg kg−1. Due to high acceptability regarding the required criteria and applicability to ovine and caprine milk, giving similar results, this multi-analyte method has been successfully implemented in pharmacokinetic research studies as well as statutory residue monitoring in Slovenia. 相似文献
96.
A discontinuous Galerkin method, with hp-adaptivity based on the approximate solution of appropriate dual problems, is employed for highly-accurate eigenvalue computations on a collection of benchmark examples. After demonstrating the effectivity of our computed error estimates on a few well-studied examples, we present results for several examples in which the coefficients of the partial-differential operators are discontinuous. The problems considered here are put forward as benchmarks upon which other adaptive methods for computing eigenvalues may be tested, with results compared to our own. 相似文献
97.
98.
Hyperfine data and g factors are reported for the radical cations of tetrathiafulvalene (TTF; 1 ) and of its derivatives 2–13 . From the intense satellite spectra of 1 +– 13 + not only the coupling constants of the 33S isotopes in the TTF moiety could be determined, but also, in favourable cases, those of the 13C isotopes in the central double bond. The former values range from 0.370 ( 8 +) to 0.470 mT ( 4 +) and the latter from 0.255 ( 8 +) to 0.360 mT ( 4 +) in the radical cations of bis(ethylenedithio)-TTF ( 8 +) and tetracyano-TTF ( 4 +). The radical cation of TTF ( 1 +) exhibits intermediate values, 0.425 for the 33S and 0.285 mT for the 13C isotopes. The spin population in 1 +– 13 + resides, to a large extent, in the central S2C ? CS2 part of the π-system. It tends to increase (decrease) by substitution with electron-accepting (donating) groups in the 2,3,6,7-positions of TTF. 相似文献
99.
Stepan J. Chundak Vukadin M. Leovac Luka J. Bjelica 《Monatshefte für Chemie / Chemical Monthly》1987,118(8-9):923-930
The reaction of aquo-ethanolic solutions of Co(II), Ni(II) and Cu(II) salts and ethanolic solution of capric acid hydrazide (L) yielded paramagnetic, high-spin bis- and tris(ligand) chelate complexes. The tris(ligand) complexes, [ML
3]X
2·nH2O [M=Co(II), Ni(II);X=NO
3
–
, ClO
4
–
, 1/2SO
4
2–
], have an octahedral structure formed on account of the bidentate (NO) coordination of three neutral hydrazide molecules. In the bis(ligand) complexes,ML
2(NCS)2 [M=Co(II), Ni(II)] and CuL
2
X
2·nH2O (X=NO
3
–
, ClO
4
–
and 1/2SO
4
2–
), the oxoanions and NCS– take also part in coordination. The complexes have been characterized by elemental analysis, IR spectra, magnetic measurements, molar conductivity and TG analysis.
Caprinsäurehydrazid-Komplexe von Co(II), Ni(II) und Cu(II)
Zusammenfassung Durch die Reaktion von wäßrig-ethanolischen Lösungen von Co(II)-, Ni(II)-und Cu(II)-Salzen mit einer ethanolischen Lösung von Caprinsäurehydrazid (L) wurden paramagnetische high-spin Bis- und Tris-Ligand-Chelatkomplexe erhalten. Tris-Ligand-Komplexe des Typs [ML 3 X 2·nH2O [M=Co(II), Ni(II);X=NO 3 – , ClO 4 – , 1/2SO 4 2– ], die eine oktaedrische Struktur besitzen, entstehen durch die Koordination von drei neutralen zweizähnigen (NO)-Hydrazidmolekülen. Bei den Bis-Ligand-KomplexenML 2(NCS)2 [M=Co(II), Ni(II)], sowie bei den Bis-Ligand-Komplexen CuL 2 X 2·nH2O (X=NO 3 – , ClO 4 – , 1/2SO 4 2– ) nehmen bei der Koordination außer Hydrazid auch die Säurereste teil. Die Komplexe wurden durch Elementaranalyse, IR-Spektren, magnetische Messungen, molare Leitfähigkeit und TG-Analysen charakterisiert.相似文献
100.