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排序方式: 共有922条查询结果,搜索用时 31 毫秒
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Parra R. A. Uddin S. Bashir Inam-ul Nanda H. Bashir W. Ahmad R. 《Journal of Experimental and Theoretical Physics》2019,129(2):217-228
Journal of Experimental and Theoretical Physics - The mid-rapidity (|y| < 0.5) transverse momentum distributions of identified charged pions produced in different collision systems at... 相似文献
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Margarita Yu. Vozhdaeva Alfiya R. Kholova Igor A. Melnitskiy Ilya I. Beloliptsev Yulia S. Vozhdaeva Evgeniy A. Kantor Albert T. Lebedev 《Molecules (Basel, Switzerland)》2021,26(7)
The main drawback of drinking water chlorination involves the formation of quite hazardous disinfection by-products (DBPs), represented mainly by halogenated species. Based on the authors’ monitoring data since 2002, the prevalence of chlorine over bromine in the composition of volatile DBPs was shown for the drinking water in Ufa (Russia). However, the situation was completely reversed in the case of semi-volatile DBPs. The principal goal of the present study involved rationalization of the results of the long-term monitoring. Gas chromatography–mass spectrometry (GC-MS) was used for the qualitative and quantitative analysis of volatile DBPs. Identification of semi-volatile compounds was carried out with GC-MS, while gas chromatography with an atomic emission detector (GC-AED) was used for their quantification. A significant contribution of oxygen to the composition of semi-volatile compounds proves the decisive role of the dissolved organic matter oxidative destructive processes. Statistical analysis revealed notable linear correlations for trihalomethane and haloacetic acid formation vs. chlorine dose. On the contrary, halogenated semi-volatile products do not demonstrate any correlations with the water quality parameters or chlorine dose. Principal component analysis (PCA) placed them into separate groups. The results allow for proposing that formation of the organohalogenated species involved the fast penetration of bromine into the humic matter molecules and, further, their oxidative destruction by active chlorine. 相似文献
35.
Ariadna Lázaro Cristina Balcells Dr. Josefina Quirante Prof. Josefa Badia Prof. Laura Baldomà Dr. Jas S. Ward Prof. Kari Rissanen Dr. Mercè Font-Bardia Prof. Laura Rodríguez Dr. Margarita Crespo Prof. Marta Cascante 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(9):1947-1952
Platinum-based chemotherapy persists to be the only effective therapeutic option against a wide variety of tumours. Nevertheless, the acquisition of platinum resistance is utterly common, ultimately cornering conventional platinum drugs to only palliative in many patients. Thus, encountering alternatives that are both effective and non-cross-resistant is urgent. In this work, we report the synthesis, reduction studies, and luminescent properties of a series of cyclometallated (C,N,N′)PtIV compounds derived from amine–imine ligands, and their remarkable efficacy at the high nanomolar range and complete lack of cross-resistance, as an intrinsic property of the platinacycle, against multiplatinum-resistant colorectal cancer (CRC) and castration-resistant prostate cancer (CRPC) metastatic cell lines generated for this work. We have also determined that the compounds are effective and selective for a broader cancer panel, including breast and lung cancer. Additionally, selected compounds have been further evaluated, finding a shift in their antiproliferative mechanism towards more cytotoxic and less cytostatic than cisplatin against cancer cells, being also able to oxidize cysteine residues and inhibit topoisomerase II, thereby holding great promise as future improved alternatives to conventional platinum drugs. 相似文献
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Anna Matveeva Zoya Starikova Margarita Passechnik Irina Odinets Tatyana Mastryukova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8-9)
The enols R 1 R 2 P(E)(CN)C = CR 3 OH (E = O or S) gave in solutions either neutral metal complexes ML x or M(OH) y L x . The anionic ambidentate ligands are coordinated through E and O atoms in solutions, and O, E, and N atoms in in crystals. 相似文献
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D. F. Parra P. L. Forster R. Łyszczek A. Ostasz A. B. Lugao Z. Rzączyńska 《Journal of Thermal Analysis and Calorimetry》2013,114(3):1049-1056
The aim of this study has been to gain a fundamental understanding of the mechanisms governing thermal degradation of luminescent poly(3-hydroxybutyrate) (PHB). PHB was doped with diaquatris(thenoyltrifluoroacetonate) europium(III) complex, [Eu(tta)3(H2O)2], and different luminescent systems were obtained. The thermal-stability of the luminescent films was discussed and the products of decomposition were analyzed. Thermal degradation of PHB:Eu(tta)3 x % systems (x = 0, 1, 5, 10, and 15 %) was elucidated by means of thermogravimetric analysis (TG), the thermal-stability decreases with the increase of europium complex concentration. The PHB polymer decomposed with evolution of carbon dioxide and 2-butenoic acid molecules. The TG–FTIR results, of the gaseous degradation products of PHB in nitrogen atmosphere, indicated that the polymer is stable at temperatures up to 200 °C. Polymer matrix at concentrations above 5 % decomposed with evolution of water molecules among the other gaseous products, which implied the presence of a hydrated complex in the system. The luminescent films showed more flexibility due to a loss in crystallinity, which suggested a potential usefulness in technical applications. 相似文献
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The Thorpe-Ziegler reaction has been used in the preparation of enaminonitriles and cyclic ketones for many years. A wide variety of bases1 have been employed to acomplish this reaction, the most effective being the alkali metal salts of aralkyl amines. The reaction conditions vary from room temperature to toluene reflux temperature for long periods of time1. 相似文献
40.
The synthesis and liquid crystalline properties of new series of 1,2,4‐ and 1,3,4‐oxadiazole derivatives (2a–f and 5a–f respectively) are reported. These compounds contain only one terminal flexible alkoxy chain, the other terminal substituent is a protecting benzyl group. All compounds of series 2 exhibit an enantiotropic nematic phase. The homologue with the longest chain (2f) displays an enantiotropic dimorphism smectic A– nematic. None of the compounds of series 5 shows mesomorphism and only crystal–isotropic transitions were observed. The liquid crystalline properties were investigated by differential scanning calorimetry, polarizing optical microscopy and X‐ray measurements. Luminescence properties, in chloroform solution, of 2f and the series 5 compounds were evaluated. Good photoluminescence quantum yields for compounds of series 5 were observed. Compound 2f, incorporating the 1,2,4‐oxadiazole ring shows a very strong reduction in emissive properties. 相似文献