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排序方式: 共有92条查询结果,搜索用时 15 毫秒
1.
New derivation results for integrands and multifunctions via the Lipschitzean approximations are obtained. Applications to multivalued differential equations on closed convex sets are presented. 相似文献
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Ibrahim Mssillou Abdelkrim Agour Aimad Allali Hamza Saghrouchni Mohammed Bourhia Abdelfattah El Moussaoui Ahmad Mohammad Salamatullah Abdulhakeem Alzahrani Mourad A. M. Aboul-Soud John P. Giesy Badiaa Lyoussi Elhoussine Derwich 《Molecules (Basel, Switzerland)》2022,27(7)
Since some synthetic insecticides cause damage to human health, compounds in plants can be viable alternatives to conventional synthetic pesticides. Dittrichia viscosa L. is a perennial Mediterranean plant known to possess biological activities, including insecticidal properties. The chemical composition of an essential oil (EOD) from D. viscosa, as well as its antioxidant, antimicrobial, and insecticidal effects on the cowpea weevil (Callosobruchus maculatus) were determined. Forty-one volatile compounds were identified in EOD, which accounted for 97.5% of its constituents. Bornyl acetate (41%) was a major compound, followed by borneol (9.3%), α-amorphene (6.6%), and caryophyllene oxide (5.7%). EOD exhibited significant antioxidant activity in all tests performed, with an IC50 of 1.30 ± 0.05 mg/mL in the DPPH test and an EC50 equal to 36.0 ± 2.5 mg/mL in the FRAP assay. In the phosphor-molybdenum test, EOD results ranged from 39.81 ± 0.7 to 192.1 ± 0.8 mg AAE/g E. EOD was active on E. coli (9.5 ± 0.5 mm), S. aureus (31.0 ± 1.5 mm), C. albicans (20.4 ± 0.5 mm), and S. cerevisiae (28.0 ± 1.0 mm), with MICs ranging from 0.1 mg/mL to 3.3 mg/mL. We found that 1 µL of EOD caused 97.5 ± 5.0% insect mortality after 96 h in the inhalation test and 60.0 ± 8.3% in the ingestion assay. The median lethal concentration (LC50) was 7.8 ± 0.3 μL EO/L, while the effective concentration in the ingestion test (LC50) was 15.0 ± 2.1 μL EO/L. We found that 20 µL of EOD caused a reduction of more than 91% of C. maculatus laid eggs. 相似文献
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Mohammed Moussaoui Alberto Seeger 《Transactions of the American Mathematical Society》1999,351(9):3687-3711
The purpose of this work is twofold: on the one hand, we study the second-order behaviour of a nonsmooth convex function defined over a reflexive Banach space . We establish several equivalent characterizations of the set , known as the second-order subdifferential of at relative to . On the other hand, we examine the case in which is the functional integral associated to a normal convex integrand . We extend a result of Chi Ngoc Do from the space to a possible nonreflexive Banach space . We also establish a formula for computing the second-order subdifferential .
6.
Trinuclear Gold Clusters Supported by Cyclic (alkyl)(amino)carbene Ligands: Mimics for Gold Heterogeneous Catalysts
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Dr. Liqun Jin David S. Weinberger Dr. Mohand Melaimi Dr. Curtis E. Moore Prof. Arnold L. Rheingold Prof. Guy Bertrand 《Angewandte Chemie (International ed. in English)》2014,53(34):9059-9063
The synthesis of air‐ and moisture‐stable trinuclear mixed‐valence gold(I)/gold(0) clusters is described. They promote the catalytic carbonylation of amines under relatively mild conditions. The synthetic route leading to the trinuclear clusters involves a simple ligand exchange from the readily available μ3‐oxo‐[(Ph3PAu)3O]+ complex. This synthetic method paves the way for the preparation of a variety of mixed‐valence gold(I)/gold(0) polynuclear clusters. Moreover, the well‐defined nature of the complexes demonstrates that the catalytic process involves a rare example of a definite change of oxidation state of gold from Au02AuI to AuI3. 相似文献
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Steffen Styra Dr. Mohand Melaimi Dr. Curtis E. Moore Prof. Arnold. L. Rheingold Timo Augenstein Prof. Dr. Frank Breher Prof. Guy Bertrand 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(23):8441-8446
A stable cyclic (alkyl)(amino)carbene (CAAC) 1 inserts into the para‐CF bond of pentafluoropyridine, and after fluoride abstraction, the iminium‐pyridyl adduct [ 3 ]+ was isolated. A cyclic voltammetry study shows a reversible three‐state redox system involving [ 3 ]+, [ 3 ] ? , and [ 3 ] ? . The CAAC‐pyridyl radical [ 3 ] ? , obtained by reduction of [ 3 ]+ with magnesium, has been spectroscopically and crystallographically characterized. In contrast to the lack of π communication between the CAAC and the pyridine units in cation [ 3 ]+, the unpaired electron of [ 3 ] ? is delocalized over an extended π system involving both heterocycles. 相似文献
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Mohammed Bouslamti Amira Metouekel Tarik Chelouati Abdelfattah El Moussaoui Azeddin El Barnossi Mohamed Chebaibi Hiba-Allah Nafidi Ahmad Mohammad Salamatullah Abdulhakeem Alzahrani Mourad A. M. Aboul-Soud Mohammed Bourhia Badiaa Lyoussi Ahmed Samir Benjelloun 《Molecules (Basel, Switzerland)》2022,27(24)
The present work was designed to study the chemical composition and the antioxidant and antimicrobial properties of fruits (SFr) and leaf (SF) extracts from Solanum elaeagnifolium var. obtusifolium (Dunal) Dunal (S. elaeagnifolium). The chemical composition was determined using HPLC-DAD analysis. Colorimetric methods were used to determine polyphenols and flavonoids. Antioxidant capacity was assessed with DPPH, TAC, and FRAP assays. Antimicrobial activity was assessed using disk diffusion and microdilution assays against two Gram (+) bacteria (Staphylococcus aureus ATCC-6633 and Bacillus subtilis DSM-6333) and two Gram (-) bacteria (Escherichia coli K-12 and Proteus mirabilis ATCC-29906), while the antifungal effect was tested vs. Candida albicans ATCC-1023. By use of in silico studies, the antioxidant and antimicrobial properties of the studied extracts were also investigated. HPLC analysis showed that both fruits and leaf extracts from S. elaeagnifolium were rich in luteolin, quercetin, gallic acid, and naringenin. Both SFr and SF generated good antioxidant activity, with IC50 values of 35.15 ± 6.09 μg/mL and 132.46 ± 11.73 μg/mL, respectively. The EC50 of SFr and SF was 35.15 ± 6.09 μg/mL and 132.46 ± 11.73 μg/mL, respectively. SFr and SF also showed a good total antioxidant capacity of 939.66 ± 5.01 μg AAE/and 890.1 ± 7.76 μg AAE/g, respectively. SFr had important antibacterial activity vs. all tested strains—most notably B. subtilis DSM-6333 and E. coli, with MICs values of 2.5 ± 0.00 mg/mL and 2.50 ± 0.00 mg/mL, respectively. SFr demonstrated potent antifungal activity against C. albicans, with an inhibition diameter of 9.00 ± 0.50 mm and an MIC of 0.31 ± 0.00 mg/mL. The in silico approach showed that all compounds detected in SFr and SF had high activity (between −5.368 and 8.416 kcal/mol) against the receptors studied, including NADPH oxidase, human acetylcholinesterase, and beta-ketoacyl-[acyl carrier protein] synthase. 相似文献
9.
Russian Journal of Organic Chemistry - A green protocol has been developed for the preparation of 2,2′-(arylmethylene)bis(3-hydroxy-5,5-dimethylcyclohex-2-en-1-ones) following the... 相似文献
10.
Reaction of dimesityl-1,8-naphthalenediylborate (1) with C6F5HgCl results in the formation of a B/Hg heteronuclear bidentate Lewis acid (2), which complexes fluoride to afford [2-mu2-F]-. Structural and photophysical studies carried out in solution and in the solid state indicate that 2 is a highly selective and sensitive phosphorescent fluoride sensor. The proximity of the two Lewis acidic sites enforced by the 1,8-naphthalenediyl backbone promotes fluoride anion chelation and is, therefore, responsible for the high binding constant. The interplay of conjugative and spin-orbit coupling effects mediated by the boron and mercury atoms, respectively, results in the phosphorescent signaling of fluoride binding. Remarkably, fluoride binding occurs in partially aqueous solutions and results in a drastic change of the phosphorescence observed when the solutions are frozen. 相似文献