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121.
Robert Bicki Katarzyna Antoniak-Jurak Kamila Michalska Ewelina Franczyk Marcin Konkol Paweł Kowalik Monika Pańczyk Janusz Ryczkowski Grzegorz Słowik Tadeusz Borowiecki 《International Journal of Hydrogen Energy》2021,46(21):11664-11676
Ni/La–Al2O3 and Ni/Ce–Al2O3 catalysts with a small amount of promoters intended for prereforming of LNG were characterized by XRF, N2 adsorption-desorption, XRD, H2 chemisorption, HRTEM and XPS. The catalytic activity was evaluated in methane steam reforming both in the kinetic and diffusion regime, at temperatures characteristic of pre-reforming. Carbonaceous deposit was analysed by TPO-MS method. The nature and location of the coke were studied by HRTEM.La or Ce addition into Ni–Al system causes the increase of the active surface area of Ni by enhancing its dispersion. Studies at kinetic regime have shown that the promoted catalysts have almost twice the activity than reference Ni–Al catalyst. This effect was not confirmed by measurements in the diffusion regime on whole catalyst tablets. Almost identical textural properties of catalysts and diffusive limitations related to them but not the catalytic properties of the material itself appeared to be crucial factors. The presence of La (but not Ce) causes a significant increase in resistance to coking. 相似文献
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123.
Beata Dbrowska-Bouta Grzegorz Sulkowski Mikoaj Saek Magorzata Frontczak-Baniewicz Lidia Struyska 《International journal of molecular sciences》2021,22(6)
Silver nanoparticles (AgNPs) are the one of the most extensively used nanomaterials. The strong antimicrobial properties of AgNPs have led to their use in a wide range of medical and consumer products. Although the neurotoxicity of AgNPs has been confirmed, the molecular mechanisms have not been extensively studied, particularly in immature organisms. Based on information gained from previous in vitro studies, in the present work, we examine whether ionotropic NMDA glutamate receptors contribute to AgNP-induced neurotoxicity in an animal model of exposure. In brains of immature rats subjected to a low dose of AgNPs, we identified ultrastructural and molecular alterations in the postsynaptic region of synapses where NMDA receptors are localized as a multiprotein complex. We revealed decreased expression of several NMDA receptor complex-related proteins, such as GluN1 and GluN2B subunits, scaffolding proteins PSD95 and SynGAP, as well as neuronal nitric oxide synthase (nNOS). Elucidating the changes in NMDA receptor-mediated molecular mechanisms induced by AgNPs, we also identified downregulation of the GluN2B-PSD95-nNOS-cGMP signaling pathway which maintains LTP/LTD processes underlying learning and memory formation during development. This observation is accompanied by decreased density of NMDA receptors, as assessed by a radioligand binding assay. The observed effects are reversible over the post-exposure time. This investigation reveals that NMDA receptors in immature rats are a target of AgNPs, thereby indicating the potential health hazard for children and infants resulting from the extensive use of products containing AgNPs. 相似文献
124.
Wojciech Polkowski Natalia Sobczak Grzegorz Bruzda Artur Kudyba Rafal Nowak Adelajda Polkowska Izabela Krzak Adam Tchrz Donatella Giuranno 《SILICON》2020,12(7):1639-1649
Silicon-boron alloys have been recently pointed out as novel ultra-high temperature phase change materials for applications in Latent Heat Thermal Energy S 相似文献
125.
Aleksander Strugaa Jakub Jagielski Karol Kamel Grzegorz Nowaczyk Marcin Radom Marek Figlerowicz Anna Urbanowicz 《International journal of molecular sciences》2021,22(6)
Virus-like particles (VLPs), due to their nanoscale dimensions, presence of interior cavities, self-organization abilities and responsiveness to environmental changes, are of interest in the field of nanotechnology. Nevertheless, comprehensive knowledge of VLP self-assembly principles is incomplete. VLP formation is governed by two types of interactions: protein–cargo and protein–protein. These interactions can be modulated by the physicochemical properties of the surroundings. Here, we used brome mosaic virus (BMV) capsid protein produced in an E. coli expression system to study the impact of ionic strength, pH and encapsulated cargo on the assembly of VLPs and their features. We showed that empty VLP assembly strongly depends on pH whereas ionic strength of the buffer plays secondary but significant role. Comparison of VLPs containing tRNA and polystyrene sulfonic acid (PSS) revealed that the structured tRNA profoundly increases VLPs stability. We also designed and produced mutated BMV capsid proteins that formed VLPs showing altered diameters and stability compared to VLPs composed of unmodified proteins. We also observed that VLPs containing unstructured polyelectrolyte (PSS) adopt compact but not necessarily more stable structures. Thus, our methodology of VLP production allows for obtaining different VLP variants and their adjustment to the incorporated cargo. 相似文献
126.
Pawe Kowalczyk Mateusz Szymczak Magdalena Maciejewska ukasz Laskowski Magdalena Laskowska Ryszard Ostaszewski Grzegorz Skiba Ida Franiak-Pietryga 《International journal of molecular sciences》2021,22(2)
Silver and its nanoparticles (AgNPs) have different faces, providing different applications. In recent years, the number of positive nanosilver applications has increased substantially. It has been proven that AgNPs inhibit the growth and survival of bacteria, including human and animal pathogens, as well as fungi, protozoa and arthropods. Silver nanoparticles are known from their antiviral and anti-cancer properties; however, they are also very popular in medical and pharmaceutical nanoengineering as carriers for precise delivery of therapeutic compounds, in the diagnostics of different diseases and in optics and chemistry, where they act as sensors, conductors and substrates for various syntheses. The activity of AgNPs has not been fully discovered; therefore, we need interdisciplinary research to fulfil this knowledge. New forms of products with silver will certainly find application in the future treatment of many complicated and difficult to treat diseases. There is still a lack of appropriate and precise legal condition regarding the circulation of nanomaterials and the rules governing their safety use. The relatively low toxicity, relative biocompatibility and selectivity of nanoparticle interaction combined with the unusual biological properties allow their use in animal production as well as in bioengineering and medicine. Despite a quite big knowledge on this topic, there is still a need to organize the data on AgNPs in relation to specific microorganisms such as bacteria, viruses or fungi. We decided to put this knowledge together and try to show positive and negative effects on prokaryotic and eukaryotic cells. 相似文献
127.
Gombert Philippe Sracek Ondra Koukouzas Nikolaos Gzyl Grzegorz Valladares Susana Tuñon Frączek Robert Klinger Christoph Bauerek Arkadiusz Areces Juan Enrique Álvarez Chamberlain Sinead Paw Krzysztof Pierzchała Łukasz 《Mine Water and the Environment》2019,38(2):463-464
Mine Water and the Environment - Correct values for radium have been rewritten in Table 1 and Table 2. Correct radium units in Figure 2(c) are Bq/L (Becquerel per liter). The same applies to... 相似文献
128.
129.
Jakub Bogusławski Yadong Wang Hui Xue Xiaoxia Yang Dong Mao Xuetao Gan Zhaoyu Ren Jianlin Zhao Qing Dai Grzegorz Soboń Jarosław Sotor Zhipei Sun 《Advanced functional materials》2018,28(28)
Actively mode‐locked lasers offer varying degrees of flexibility for a wider range of applications than their passively modulated counterparts, due to their capability for electrically controlled ultrahigh repetition rate operation. Graphene based electrooptic modulators with unique advantages of broad operation bandwidth and ultrafast speed are suitable for light modulation in various optoelectronic applications. Here, an actively mode‐locked laser with a graphene based electrooptic modulator is reported for the first time. The active mode‐locking technique combined together with the intracavity nonlinear pulse shortening effect allows the generation of transform‐limited 1.44 ps pulses with pulse energy of 844 pJ. The electrically controlled repetition rate of generated pulses, a key performance advantage of active mode‐locking, is also demonstrated. These results provide a practical and effective approach for actively mode‐locked lasers with broad operation bandwidth and compact footprint, which contributes a new way for applications of two‐dimensional (2D) layered materials in ultrafast lasers. 相似文献
130.
Wetting,reactivity, and phase formation at interfaces between Ni–Al melts and TiB2 ultrahigh‐temperature ceramic
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Lixia Xi Ivan Kaban Rafal Nowak Grzegorz Bruzda Natalia Sobczak Jürgen Eckert 《Journal of the American Ceramic Society》2018,101(2):911-918
The wetting, reactivity, and phase formation at the liquid Ni–Al/TiB2 ceramic interfaces have been investigated at the temperatures close to the Ni–Al liquidus line. The wetting kinetics has been studied by the sessile drop technique utilizing liquid drop dispension and high‐speed high‐resolution video imaging. It is established that the wetting behavior changes from a nonreactive for the Al‐rich melts to a dissolution‐reactive for the Ni‐rich melts. For the Ni concentration ≥40 at.%, TiB2 precipitates are found in the solidified Ni–Al droplets after the high‐temperature interaction of the melts with TiB2 substrates. Besides, new (Al,Ti)Ni3 and (Al,Ti)2Ni21B6 phases are formed due to dissolution of TiB2 ceramic in Ni‐rich melts and subsequent solidification. 相似文献