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101.
102.
Gomes João Pedro Agra Mourão Eduard David Simões dos Anjos Janaina Versiani de Alencar Filho Edilson Beserra 《Structural chemistry》2020,31(6):2501-2512
Structural Chemistry - In this paper, we present a quantitative structure–activity relationships modelling for two series of heterocyclic synthetic compounds with larvicidal activity against... 相似文献
103.
Ana Salomé Pires João Batista Dina Murtinho Célia Nogueira Anna Karamysheva M. Luísa Ramos Bruce F. Milne Nuno Tiago Tavares José Gonçalves Ana Cristina Gonçalves Ana Margarida Abrantes Rui Soares Teresa Gonçalves Maria Filomena Botelho M. Elisa Silva Serra 《应用有机金属化学》2020,34(5):e5569
Platinum metal complexes are the most common chemotherapeutics currently used in cancer treatment. However, the frequent adverse effects, as well as acquired resistance by tumor cells, urge the development of effective alternatives. In the recent past, copper complexes with Schiff base ligands have emerged as good alternatives, showing interesting results. Accordingly, and in continuation of previous studies in this area, three new camphoric acid-derived halogenated salen ligands and their corresponding Cu (II) complexes were synthesized and their antitumor activity was evaluated in order to determine the influence of the type and number of halogens present (Br, Cl). The in vitro cytotoxic activity was screened against colorectal WiDr and LS1034 and against breast MCF-7 and HCC1806 cancer cell lines. The results proved the halogenated complexes to be very efficient, the tetrachlorinated Cu (II) complex being the most promising, presenting IC50 of 0.63–1.09 μM for the cell lines studied. The complex also shows selectivity to colorectal cancer cells compared to non-tumor colon cells. It is worth highlighting that the tetrachlorinated Cu (II) complex, our most efficient complex, shows a significantly more powerful antitumor effect than the reference drugs currently used in conventional chemotherapy. The halogenated salen and corresponding complexes were also screened for their antimicrobial activity against four bacterial species-Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa-and four fungal species-Candida albicans, Candida glabrata, Aspergillus fumigatus and Alternaria alternata. The compounds were found to exhibit moderate to strong antibacterial activity against the bacterial strains studied. NMR studies and theoretical calculations provided some insight into the structure of the ligands and copper complexes. Considering the results presented herein, our work validates the potential use of copper-based chemotherapeutics as alternatives for cancer treatment. 相似文献
104.
The Ramanujan Journal - Let $${\mathcal {A}}$$ , $${\mathcal {B}}$$ be large subsets of $$\{1,\ldots ,N\}$$ . We study the distribution of the sum of binary digits of the sums $$a+b$$ with... 相似文献
105.
We present some features of the smooth structure and of the canonical stratification on the orbit space of a proper Lie groupoid. One of the main features is that of Morita invariance of these structures—it allows us to talk about the canonical structure of differentiable stratified space on the orbispace (an object analogous to a separated stack in algebraic geometry) presented by the proper Lie groupoid. The canonical smooth structure on an orbispace is studied mainly via Spallek’s framework of differentiable spaces, and two alternative frameworks are then presented. For the canonical stratification on an orbispace, we extend the similar theory coming from proper Lie group actions. We make no claim to originality. The goal of these notes is simply to give a complementary exposition to those available and to clarify some subtle points where the literature can sometimes be confusing, even in the classical case of proper Lie group actions. 相似文献
106.
Analysis and fragmentation mechanisms of hirsutinolide‐type sesquiterpene lactones by ultra‐high‐performance liquid chromatography/electrospray ionization linear ion trap Orbitrap mass spectrometry 下载免费PDF全文
107.
Seung Yoon Ryu Sung Hyun Kim Chang Su Kim Sungjin Jo Jun Yeob Lee 《Current Applied Physics》2012,12(5):1378-1380
Stacked organic light-emitting diodes (SOLEDs) with 30-nm nanoparticle (NP) interfacial layers were investigated. Zinc oxide (ZnO) was used as an interfacial layer between two green polymer (GP) layers. SOLEDs with NP interfacial layers had higher device efficiency than did a single-unit device due to the high probability of exciton recombination that originated from the Auger electron-assisted energy up-conversion process. Although the current density and luminance of SOLEDs with ZnO NP interfacial layers were smaller than those of the reference device, the efficiency was doubled because of the big band alignment difference and the large band gap between GP and ZnO NP interfacial layers, which induced more radiative-exciton recombination. 相似文献
108.
Dae Sung You Chang Su Kim Yong Jin KangKyounga Lim Sunghoon JungDo-Geun Kim Jong-Kuk KimSungjin Jo Joo Hyun Kim Jae-Wook Kang 《Current Applied Physics》2012,12(3):908-910
We report on the fabrication of efficient annealing-free organic solar cells using co-solvent solution considered as a promising method for low-cost and time-saving manufacturing. Higher device efficiency could be obtained compared to the pure solvent casted device, resulting from the improved crystallinity, optical absorption and transport properties. The power conversion efficiency of 2.8% was obtained, demonstrating the feasibility of achieving low-cost and high-efficiency organic solar cells without any additional treatment and processing additives. 相似文献
109.
Maria Jo?o Carrilho Plancha Carmen Mireya Rangel César Augusto Correia de Sequeira 《Journal of Solid State Electrochemistry》2012,16(2):665-671
The (PEO)4ZnCl2 electrolyte (PEO, polyethylene oxide) was studied in view of its potential application in a solid-state rechargeable zinc
cell. The electrochemical stability window was established, and decomposition voltage values between 3.19 (20 °C) and 1.44 V
(150 °C) were estimated. Cyclic voltammetry studies using a Pt/(PEO)4ZnCl2/Pt cell indicated reversibility of the Zn2+/Zn couple at the electrode/electrolyte interface. Laboratory cells Zn(−)/(PEO)4ZnCl2/Nb2O5(+) were assembled and studied at 55 °C, under various discharge current densities. Results of cell discharge profiles, capacity
values, charge–discharge cycles and cell stabilities are reported. 相似文献
110.
Christelle Mouveaux Fabienne Hochart Joëlle Levalois-Mitjaville Roger De Jaeger 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Multisite receptors containing more than two macrocyclic cavities. despite of the fact that their syntheses, most often, require sophisticated pathways, arc of very high interest since they may allow new insights into ion channel transfer, ion conduction.[1] We report here a method which combine simple reactions, high yields (80%), with easily prepared starting reagents[2], of two new polymacrocyclic system, a tri-(r) and an hexamacrocyck(II). They were obtained by a condensation reaction between 4-formylbenzo-15-crown-5 (3 or 6 quiv, respectively) and phosphouihydrazide (1 equiv.) or hexahydrazide (1 equiv.) in tetrahydrofuran. 相似文献