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Andrzej Stokiosa Janusz ZajÇcki Grzegorz Wilczyński Anna Wójtowicz Stefan S. Kurek 《Catalysis Letters》1996,37(1-2):89-94
Results of studies on the influence of a copper catalyst modification with zinc ions on the activity in the reaction of cyclohexanol dehydrogenation are presented. The modification has been performed by electrochemical discharging-insertion of zinc ions on a copper electrode in a non-aqueous cell. It has been demonstrated that the catalyst activity depends on the amount of discharged zinc ions as well as on the nature and concentration of the electrolyte. In the case of zinc ions discharged from a solution of ZnCl2 in propylene carbonate, the yield of cyclohexanone increased up to five times and using Zn(BF4)2 in dimethylformamide almost twenty times. The activity of the system in the competing reaction of dehydration was low, hence the selectivity in the dehydrogenation reaction was high. 相似文献
143.
Janina Molenda Mariusz Ziemnicki Jacek Marzec Wojciech Zając Marcin Molenda Mirosław Bućko 《Journal of power sources》2007
In this work we report the investigation of the structural and the electrical properties of orthorhombic LiMnO2 in a wide temperature range in air and in high purity argon (N5). Also we present a correlation between the electrical and the electrochemical properties of the material upon lithium deintercalation. Moreover, its chemical stability against LiPF6 based liquid electrolyte at elevated temperatures was measured and compared with other cathode materials. 相似文献
144.
The paper summarizes and discusses the basic properties of solid oxide fuel cell (SOFC) components (electrode materials and electrolyte) from the point of view of their essential functional parameters like chemical stability, transport, catalytic and thermomechanical properties under operational conditions in a SOFC. An interrelation between the defect structure of these materials related to oxygen nonstoichiometry and their electrical properties and catalytic activity was shown. 相似文献
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Piotr Hapeta Patrycja Szczepaska Tadeusz Witkowski Jean-Marc Nicaud Anne-Marie Crutz-Le Coq Zbigniew Lazar 《International journal of molecular sciences》2021,22(17)
The development of efficient bioprocesses requires inexpensive and renewable substrates. Molasses, a by-product of the sugar industry, contains mostly sucrose, a disaccharide composed of glucose and fructose, both easily absorbed by microorganisms. Yarrowia lipolytica, a platform for the production of various chemicals, can be engineered for sucrose utilization by heterologous invertase expression, yet the problem of preferential use of glucose over fructose remains, as fructose consumption begins only after glucose depletion what significantly extends the bioprocesses. We investigated the role of hexose transporters and hexokinase (native and fructophilic) in this preference. Analysis of growth profiles and kinetics of monosaccharide utilization has proven that the glucose preference in Y. lipolytica depends primarily on the affinity of native hexokinase for glucose. Interestingly, combined overexpression of either hexokinase with hexose transporters significantly accelerated citric acid biosynthesis and enhanced pentose phosphate pathway leading to secretion of polyols (31.5 g/L vs. no polyols in the control strain). So far, polyol biosynthesis was efficient in glycerol-containing media. Moreover, overexpression of fructophilic hexokinase in combination with hexose transporters not only shortened this process to 48 h (84 h for the medium with glycerol) but also allowed to obtain 23% more polyols (40 g/L) compared to the glycerol medium (32.5 g/L). 相似文献
148.
Vitreoretinal surgery has become a widely used ophthalmic surgical procedure since the late sixties. However, it remained an intensively developing field of surgical interventions, and indications still become wider and wider. The procedure starts with the removal of vitreous body, blood or inflammatory material from the vitreous cavity. After this, the given retinal disease, such as retinal detachment, macular hole, proliferative diabetic retinopathy, intraocular foreign body, etc. can be properly treated in situ. For that purpose a number of fine intraocular instruments, fluids, gases can be used. While the anatomical success rate can be up to 95%, the final visual outcome, due to the fact that the retina is not rarely seriously damaged, is less enthusiastic. However, a great number of previously untreatable vitreoretinal diseases can be managed in this way, nowadays. 相似文献
149.
Patrycja Koszaka Grzegorz Stasioj Natalia Mikus-Purwin Maciej Nied
wiecki Maciej Purwin Szymon Grabowski Tomasz Bczek 《International journal of molecular sciences》2022,23(9)
Acute lymphoblastic leukemia (ALL) is the most common hematological malignancy affecting pediatric patients. ALL treatment regimens with cytostatics manifest substantial toxicity and have reached the maximum of well-tolerated doses. One potential approach for improving treatment efficiency could be supplementation of the current regimen with naturally occurring phytochemicals with anti-cancer properties. Nutraceuticals such as quercetin, curcumin, resveratrol, and genistein have been studied in anti-cancer therapy, but their application is limited by their low bioavailability. However, their cooperative activity could potentially increase their efficiency at low, bioavailable doses. We studied their cooperative effect on the viability of a human ALL MOLT-4 cell line in vitro at the concentration considered to be in the bioavailable range in vivo. To analyze their potential side effect on the viability of non-tumor cells, we evaluated their toxicity on a normal human foreskin fibroblast cell line (BJ). In both cell lines, we also measured specific indicators of cell death, changes in cell membrane permeability (CMP), and mitochondrial membrane potential (MMP). Even at a low bioavailable concentration, genistein and curcumin decreased MOLT-4 viability, and their combination had a significant interactive effect. While resveratrol and quercetin did not affect MOLT-4 viability, together they enhanced the effect of the genistein/curcumin mix, significantly inhibiting MOLT-4 population growth in vitro. Moreover, the analyzed phytochemicals and their combinations did not affect the BJ cell line. In both cell lines, they induced a decrease in MMP and correlating CMP changes, but in non-tumor cells, both metabolic activity and cell membrane continuity were restored in time. (4) Conclusions: The results indicate that the interactive activity of analyzed phytochemicals can induce an anti-cancer effect on ALL cells without a significant effect on non-tumor cells. It implies that the application of the combinations of phytochemicals an anti-cancer treatment supplement could be worth further investigation regardless of their low bioavailability. 相似文献
150.
Patrycja Kos Elbieta Porba Ewa Springer Eleonora Lampart-Szczapa Anna Godzicka Józefiak 《Journal of food science》2010,75(1):H39-H43
ABSTRACT: Since lupin has been introduced as a food ingredient on the market there are more and more reports concerning its allergenic properties. However, only few narrow-leafed lupin proteins have yet been characterized as specific IgE-binding molecules and identified. The aim of the study has been to find and identify the main narrow-leafed lupin globulins that bind to specific IgEs from the sera of lupin-allergic people. Isolated lupin globulins were subjected to immunoblotting with the sera from people who suffered from lupin allergy. Incubation with α-methyl-D-galactopyranoside was performed to eliminate possible binding of unspecific human IgEs. The proteins binding specific IgEs from lupin-allergic patients' sera were identified by means of mass spectrometry. Western blot analysis revealed 2 signals corresponding to lupin globulins that bound to specific IgEs from the sera of people allergic to lupin. The globulins were identified as conglutin-γ and its smaller subunit. The results suggested that individuals that displayed lupin allergy symptoms reacted to conglutin-γ.
Practical Application: The results of the study can contribute to identification of yet undetected allergens of narrow-leafed lupin. This, in turn, can make lupin-fortified products safer for the consumers. 相似文献
Practical Application: The results of the study can contribute to identification of yet undetected allergens of narrow-leafed lupin. This, in turn, can make lupin-fortified products safer for the consumers. 相似文献