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排序方式: 共有300条查询结果,搜索用时 46 毫秒
11.
Sylvain Maclot Michael Capron Rémi Maisonny Arkadiusz Ławicki Dr. Alain Méry Dr. Jimmy Rangama Prof. Dr. Jean‐Yves Chesnel Sadia Bari Prof. Dr. Ronnie Hoekstra Dr. Thomas Schlathölter Prof. Dr. Bruno Manil Prof. Dr. Lamri Adoui Dr. Patrick Rousseau Prof. Dr. Bernd A. Huber 《Chemphyschem》2011,12(5):881-881
12.
13.
Nikica Šprem Ivan Babić Domagoj Barišić Delko Barišić 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(1):513-517
The aim of this study was to investigate 137Cs and 40K load in large mammal game species in the mountain forest region of Gorski Kotar in Croatia approximately a quarter of century after the Chernobyl accident. 137Cs and 40K activity were determined by the gamma-spectrometric method in 49 meat samples of five large game species: brown bear (Ursus arctos), wild boar (Sus scrofa), roe deer (Capreolus capreolus), red deer (Cervus elaphus), and chamois (Rupicapra rupicapra). The results indicated that herbivore game species (roe deer, red deer and chamois) show significantly lower 137Cs concentrations than omnivore species (brown bear, wild boar), thereby confirming the hypothesis that different dietary strategy impact caesium concentrations in meat. The measured caesium load in brown bear meat was in the range of two orders of magnitude, while caesium load in wild boar meat was found in the range of one order of magnitude. The estimated effective equivalent dose showed that uptake of the highest caesium doses would be from consumption of omnivore species meat, while much lower doses could be taken in with the consumption of meat from herbivore species. 相似文献
14.
Saeed Ali Syed Ahmed Bari Mohammed S. Aldughaim Md Abdur Rashid Mohammad Hossain Shariare Mohsin Kazi 《Molecules (Basel, Switzerland)》2021,26(1)
In recent years, indole derivatives have acquired conspicuous significance due to their wide spectrum of biological activities—antibacterial, antiviral, and anticonvulsant. This compound is derived from naturally grown plants. Therefore, synthesis of a novel “3-(Naphthalen-1-ylimino)indolin-2-one” compound (2) and its analysis using UPLC systems along with antimicrobial assessment was the aim of the current study. Isatin was used as a parent drug for synthesizing compound (2). Liquid Chromatographic analysis was performed using a C18 BEH column (1.7 μm 2.1 × 50 mm) by UPLC systems. Degradation studies were carried out to see whether acid, base, thermal, and oxidizing agents had any impact on the synthesized molecule in stress conditions (100 °C). A lipid-based self-nanoemulsifying formulation was developed and selectivity, specificity, recovery, accuracy, and precision were measured as part of the UPLC system’s validation process. Antimicrobial studies were conducted using gram-positive and gram-negative bacteria. The standard samples were run with a concentration range of 5.0–100.0 μg/mL using the isocratic mobile phase comprising of methanol/water (70/30 %v/v) at 234 nm; good linearity (R2 = 0.9998) was found. The lower limits of detection (LOD) and quantitation (LOQ) of the method were found to be 0.81 μg/mL and 2.5 μg/mL, respectively. The coefficients of variation were found to be less than 2%. The antimicrobial study suggests that compound (2) has a substantial growth effect against gram-negative bacteria. It was successfully synthesized and applied to measure the concentrations in lipid-based dosage form, along with potent antimicrobial activities. 相似文献
15.
Shiwani Berry Shamsher S. Bari Pooja Yadav Ankita Garg Sadhika Khullar Sanjay K. Mandal 《合成通讯》2020,50(19):2969-2980
Abstract An efficient protocol for the stereoselective synthesis of pyrazolo[5,1-b]thiazole-3-carboxylate tethered β-lactam conjugates 8a–j from novel pyrazolo [5,1-b]thiazole-3-carboxylate substituted Schiff’s bases 6a–f is reported here. The reaction between various ketene precursors and novel Schiff’s bases 6a–f afforded exclusive formation of trans-β-lactams 8a–j. The substrate scope of this approach was investigated extensively by varying different groups (R, Z). All the novel compounds were characterized using various spectroscopic techniques, such as FT-IR, 1H NMR, 13C NMR, elemental analysis, 13C NMR (DEPT-135), and mass spectrometry in representative cases. Single crystal X-ray crystallographic study of trans-ethyl 7-(1-(4-methoxyphenyl)-4-oxo-3-phenoxyazetidin-2-yl)-6-methyl-2-(methylthio)pyrazolo[5,1-b]thiazole-3-carboxylate 8a has confirmed the molecular structure and the stereochemical outcome. To the best of our knowledge, the synthesis of such types of Schiff’s bases and β-lactam conjugates has not been reported so far. 相似文献
16.
Jae Won Chang Mohammed Bhuiyan Hsiu‐Ming Tsai Hannah J. Zhang Gang Li Shaghayegh Fathi David C. McCutcheon Lara Leoni Richard Freifelder Chin‐Tu Chen Raymond E. Moellering 《Angewandte Chemie (International ed. in English)》2020,59(35):15161-15165
Herein, we report the development of an 18F‐labeled, activity‐based small‐molecule probe targeting the cancer‐associated serine hydrolase NCEH1. We undertook a focused medicinal chemistry campaign to simultaneously preserve potent and specific NCEH1 labeling in live cells and animals, while permitting facile 18F radionuclide incorporation required for PET imaging. The resulting molecule, [18F]JW199, labels active NCEH1 in live cells at nanomolar concentrations and greater than 1000‐fold selectivity relative to other serine hydrolases. [18F]JW199 displays rapid, NCEH1‐dependent accumulation in mouse tissues. Finally, we demonstrate that [18F]JW199 labels aggressive cancer tumor cells in vivo, which uncovered localized NCEH1 activity at the leading edge of triple‐negative breast cancer tumors, suggesting roles for NCEH1 in tumor aggressiveness and metastasis. 相似文献
17.
Inside Back Cover: Circularly Polarized Luminescence from Axially Chiral BODIPY DYEmers: An Experimental and Computational Study (Chem. Eur. J. 45/2016) 下载免费PDF全文
18.
Tahir Sofilić Delko Barišić Alenka Rastovčan Mioč Una Sofilić 《Journal of Radioanalytical and Nuclear Chemistry》2010,284(1):73-77
The objective of this study was to describe the radiochemical characteristics of electric arc furnace (EAF) slag from Croatian EAF black steel slags, generated from carbon steel production process in CMC Sisak d.o.o., and steel mill in Split in order to enhance the understanding of possibilities for their use in road construction. This article presents the results of radionuclide in electric arc furnace steel slag. The presence of natural isotopes 40K, 232Th (228Ra), 226Ra and 238U was established. The measured activity in slag natural isotopes lies within the Croatian legally permitted limits. 相似文献
19.
D. K.?SunkoEmail author S.?Bari?i? 《The European Physical Journal B - Condensed Matter and Complex Systems》2005,46(2):269-279
We study the effect of antiferromagnetic (AF) correlations in the three-band
Emery model, with respect to the experimental situation in weakly underdoped
and optimally doped BSCCO. In the vicinity of the vH singularity of the
conduction band there appears a central peak in the middle of a pseudogap,
which is in an antiadiabatic regime, insensitive to the time scale of the
mechanism responsible for the pseudogap. We find a quantum low-temperature
regime corresponding to experiment, in which the pseudogap is created by
zero-point motion of the magnons, as opposed to the usual semiclassical
derivation, where it is due to a divergence of the magnon occupation number.
Detailed analysis of the spectral functions along the (π,0)–(π,π)
line show significant agreement with experiment, both qualitative and, in the
principal scales, quantitative. The observed slight approaching-then-receding
of both the wide and narrow peaks with respect to the Fermi energy is also
reproduced. We conclude that optimally doped BSCCO has a well-developed
pseudogap of the order of 1000 K. This is only masked by the narrow
antiadiabatic peak, which provides a small energy scale, unrelated to the AF
scale, and primarily controlled by the position of the chemical potential. 相似文献
20.
Danijela Bari? 《Tetrahedron letters》2008,49(8):1428-1431
The origin of the angular strain is studied in deformed methane and cyclohexane selected as the model systems par excellence. It is shown that the electron correlation contribution to the angular strain is negligible. Analysis of the Hartree-Fock energies provides a convincing evidence that the angular strain is a consequence of the unfavourable nucleus-electron attraction occuring due to bond bending. This should take place in other angularly distorted molecules as a rule. However, other effects might be even more important sometimes. In these cases the Vne term can serve as a useful diagnostic tool. 相似文献