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  • 1
    In: Scientific Reports, Springer Science and Business Media LLC, Vol. 11, No. 1 ( 2021-04-21)
    Abstract: Carbon nanotubes (CNTs) are materials with exceptional electrical, thermal, mechanical, and optical properties. Ever since it was demonstrated that they also possess interesting thermoelectric properties, they have been considered a promising solution for thermal energy harvesting. In this study, we present a simple method to enhance their performance. For this purpose, thin films obtained from high-quality single-walled CNTs (SWCNTs) were doped with a spectrum of inorganic and organic halide compounds. We studied how incorporating various halide species affects the electrical conductivity, the Seebeck coefficient, and the Power Factor. Since thermoelectric devices operate under non-ambient conditions, we also evaluated these materials' performance at elevated temperatures. Our research shows that appropriate dopant selection can result in almost fivefold improvement to the Power Factor compared to the pristine material. We also demonstrate that the chemical potential of the starting CNT network determines its properties, which is important for deciphering the true impact of chemical and physical functionalization of such ensembles.
    Type of Medium: Online Resource
    ISSN: 2045-2322
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2021
    detail.hit.zdb_id: 2615211-3
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  • 2
    In: Nanomaterials, MDPI AG, Vol. 9, No. 8 ( 2019-08-02), p. 1113-
    Abstract: Despite the widespread use of sonication for individualization of nanomaterials, its destructive nature is rarely acknowledged. In this study, we demonstrated how exposure of the material to a hostile sound wave environment can be limited by the application of another preprocessing step. Single-walled carbon nanotubes (CNTs) were initially ground in a household coffee grinder, which enabled facile deagglomeration thereof. Such a simple approach enabled us to obtain high-quality CNT dispersion at reduced sonication time. Most importantly, electrical conductivity of free-standing films prepared from these dispersion was improved almost fourfold as compared with unground material eventually reaching 1067 ± 34 S/cm. This work presents a new approach as to how electrical properties of nanocarbon ensembles may be enhanced without the application of doping agents, the presence of which is often ephemeral.
    Type of Medium: Online Resource
    ISSN: 2079-4991
    Language: English
    Publisher: MDPI AG
    Publication Date: 2019
    detail.hit.zdb_id: 2662255-5
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  • 3
    Online Resource
    Online Resource
    The Electrochemical Society ; 2022
    In:  ECS Meeting Abstracts Vol. MA2022-01, No. 9 ( 2022-07-07), p. 760-760
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2022-01, No. 9 ( 2022-07-07), p. 760-760
    Abstract: Macroscopic objects such as fibers and films formed from a combination of nanocarbon materials and polymers have promising electrical [1], thermal [2] , thermoelectric [3], and mechanical [4] properties. In particular, composites of nanocarbon and conductive polymers revealed that they can constitute key parts of batteries [1] and thermoelectric generators [3] . In literature, it is possible to find many synthesis methods of this type of material. One of the most common approaches is electrochemical, wherein monomers are polymerized onto the nanocarbon surface due to its highly conducting nature [5]. Polyaniline (PANI) is the oldest and still one of the most popular conductive polymers used in this area. That is because PANI is relatively simple to manufacture at low cost and effort. Moreover, it has good mechanical strength and tunable electrical conductivity, which depend on the kind of PANI. This polymer has three forms: pernigraniline – fully oxidized (purpure/red), emeraldine – partially oxidized (blue/violet), and leucoemeraldine – fully reduced (black) [6] . Emeraldine achieves the highest conductivity when doped with Brøstead acids such as HCl, H 2 SO 4, HBF 4 [7]. The goal of this study was to exploit the phenomenon of the hydrophilic surface of carbon nanostructure caused by thermal annealing, described by us previously [8], to electropolymerize aniline onto free-standing films from nanocarbon. The films were manufactured by the wet method [8] using single-walled nanotubes (SWCNTs) exclusively and SWCNTs/graphene nanoplatelet composite. Electropolymerization was used to synthesize PANI on the surface of these materials. To establish the parameters of synthesis of different forms of PANI, voltage ranges between [(-1.6 V) – (1.6 V)] were investigated. The films were tested as a counter and a working electrode in this process. After the synthesis, the composites were investigated by optical and Scanning Electron Microscopy, Raman spectroscopy, Atomic Force Microscopy. Moreover, water contact angles, electrical conductivity values, and Seebeck coefficients were determined. Composites containing all three PANI forms have been synthesized and thoroughly analyzed to elucidate the structure-property relations. Consequently, correlations between the forms of PANI and the characteristics of nanocomposites were established. Depending on the amount and type of PANI on the surface, the character of the nanocarbon films was affected considerably. For example, coating of the material with emeraldine salts enhanced the electrical conductivity of the films by about 60% [9] , while simultaneously making the material much stronger. [1] L. Xiao, Y.H. Sehlleier, S. Dobrowolny, F. Mahlendorf, A. Heinzel, C. Schulz, H. Wiggers, Novel Si-CNT/polyaniline nanocomposites as Lithium-ion battery anodes for improved cycling performance, Mater. Today Proc. 4 (2017) S263–S268. doi:10.1016/J.MATPR.2017.09.197. [2] Z. Duan, Y. Luo, Z. Luo, W. Yu, C. Liu, S. Fan, The influence of charging and discharging on the thermal properties of a carbon nanotube/polyaniline nanocomposite electrode, RSC Adv. 9 (2019) 7629–7634. doi:10.1039/C9RA00151D. [3] R. Wu, H. Yuan, C. Liu, J. Le Lan, X. Yang, Y.H. Lin, Flexible PANI/SWCNT thermoelectric films with ultrahigh electrical conductivity, RSC Adv. 8 (2018) 26011–26019. doi:10.1039/c8ra04863k. [4] M.R. Saeb, P. Zarrintaj, Polyaniline/graphene-based nanocomposites, Fundam. Emerg. Appl. Polyaniline. (2019) 165–175. doi:10.1016/B978-0-12-817915-4.00010-5. [5] C. Oueiny, S. Berlioz, F.X. Perrin, Carbon nanotube–polyaniline composites, Prog. Polym. Sci. 39 (2014) 707–748. doi:10.1016/J.PROGPOLYMSCI.2013.08.009. [6] S.C. Rasmussen, The Early History of Polyaniline: Discovery and Origins, An Int. J. Hist. Chem. Subst. 1 (2017) 99–109. doi:10.13128/substantia-30. [7] Q. Qin, Y. Guo, Preparation and characterization of nano-polyaniline film on ITO conductive glass by electrochemical polymerization, J. Nanomater. 2012 (2012). doi:10.1155/2012/519674. [8] D. Janas, G. Stando, Unexpectedly strong hydrophilic character of free-standing thin films from carbon nanotubes, Sci. Rep. 7 (2017) 12274. doi:10.1038/s41598-017-12443-y. [9] G.Stando, P. Stando, P. Chulkin, M. Salhman, M. Lundström, D. Janas, Electropolymerization of aniline onto hydrophilic nanocarbon films (in preparation) G.S. and P.S. would like to thank the Ministry of Science and Higher Education of Poland for financial support of research (under Diamond Grant, grant agreement 0036/DIA/201948). G.S. also would like to thank European Union for thanks for financing the costs of the conference (European Social Fund, grant nr POWR.03.05.00-00-Z305) and National Agency for Academic Exchange of Poland (under the Iwanowska program, grant agreement PPN/IWA/2019/1/00017/UO/00001) for financial support during the stay at the University of Pittsburgh in the USA. G.S. and H.L. acknowledge NSF (CBET-2028826) for partial support of this work. P. S. acknowledges the National Agency for Academic Exchange of Poland (under the Academic International Partnerships program, grant agreement PPI/APM/2018/1/00004) for supporting training in the Aalto University. G.S, P.S and D.J. would like to thank the National Centre for Research and Development, Poland (under the Leader program, grant agreement LIDER/0001/L-8/16/NCBR/2017).
    Type of Medium: Online Resource
    ISSN: 2151-2043
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2022
    detail.hit.zdb_id: 2438749-6
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  • 4
    In: Electrochimica Acta, Elsevier BV, Vol. 463 ( 2023-09), p. 142842-
    Type of Medium: Online Resource
    ISSN: 0013-4686
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2023
    detail.hit.zdb_id: 1483548-4
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  • 5
    Online Resource
    Online Resource
    The Electrochemical Society ; 2023
    In:  ECS Meeting Abstracts Vol. MA2023-01, No. 10 ( 2023-08-28), p. 1189-1189
    In: ECS Meeting Abstracts, The Electrochemical Society, Vol. MA2023-01, No. 10 ( 2023-08-28), p. 1189-1189
    Abstract: Nanocarbon films are characterized by high surface area [1] , appreciable electrical conductivity [2] , and good mechanical properties [3] . These properties make them suitable for application as electrode materials in various electrochemical processes. For instance, nanocarbon electrodes can be used for selective deposition of metals onto their surface [4] . In particular, it is beneficial to accumulate Cu atoms on the surface of carbon nanomaterials as such composite exhibits much improved electrical conductivity and strength. To make this process as efficient as possible, functional groups containing oxygen or nitrogen are attached to the nanocarbon surface, prior to electrodeposition, but their presence may deteriorate the capabilities of material for charge propagation. Alternatively, conductive polymers such as polyaniline (PANI) can be physically attached to carbon to improve their electrochemical properties [5] , without introducing defects in the structure that negatively affect the electrical properties of the material. Different forms of PANI have substantial effects on the properties of composites, emeraldine salts (ES) have been chosen based upon their higher electrical properties. ES are characterized by the highest increase in electrical and mechanical properties of composites. Our research focused on the selective deposition of metals onto ES-nanocarbon composites from industrial wastewaters, which contained such metals as magnesium, iron, nickel, and copper. Aniline was electropolymerized onto the nanocarbon surface by cyclic voltammetry to make the material more suitable for recovery of metals from such source. The process of copper recovery was highly selective, which was confirmed by characterization of the surface by EDX mapping. Despite the trace amounts of copper (428 ppm) in the used industrial wastewater, Cu nanoparticles were highly visible on the PANI-nanocarbon surface after just one hour of the process. Analogously, nickel has also been recovered by this method, which demonstrates that the presented approach may be tuned for deposition of various metals onto nanocarbon to make previously unreported nanocarbon-metal composites. P.S. would like to thank the Ministry of Education and Science (MEiN/2022/DIR/3086) of Poland for financial support, which enabled the attendance to the conference. G.S. and P.S. would like to thank the Ministry of Education and Science of Poland for financial support of scientific work from budget funds for science in the years 2019–2023 as a research project under the “Diamond Grant” program (grant agreement 0036/DIA/201948). G.S., P.S. and D.J. would like to thank the National Centre for Research and Development, Poland (under the Leader program, grant agreement LIDER/0001/L-8/16/NCBR/2017). P.S. acknowledges the National Agency for Academic Exchange of Poland (NAWA, (under the Academic International Partnerships program, grant agreement PPI/APM/2018/1/00004) for supporting training in the Aalto University, which enabled the execution of the study. GS would like to thank also NAWA (under the Iwanowska program, grant agreement PPN/IWA/2019/1/00017/UO/00001) for financial support during the stay at the University of Pittsburgh in the USA. M. Cadek et al, Nano Letters, 2004, 4, 2, 353–356 G. Stando et al, Scientific Reports, 2022, 12, 4358 J. Salvetat et al. Appl Phys A, 1999, 69, 255–260 G. Stando et al, Water Resources and Industry, 2021, 26, 100156 A. Kumar et al, Polymer-Plastics Technology and Engineering , 2018, 57, 2, 70-97
    Type of Medium: Online Resource
    ISSN: 2151-2043
    Language: Unknown
    Publisher: The Electrochemical Society
    Publication Date: 2023
    detail.hit.zdb_id: 2438749-6
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  • 6
    In: Biomedicines, MDPI AG, Vol. 10, No. 10 ( 2022-10-08), p. 2514-
    Abstract: The prognostic value of inflammatory indices, such as the absolute monocyte count (AMC), has been a subject of interest in recent prostate cancer (PCa) studies, while hemoglobin concentration (HGB) has been recognized as a survival factor in castration-resistant metastatic prostate cancer, but its value remains unclear in localized diseases. The aim of this study was to test the prognostic value of these two simple and inexpensive biomarkers for survival and was based on a cohort of 1016 patients treated with primary radiotherapy and androgen deprivation therapy for localized or locally advanced intermediate- or high-risk PCa. Complete survival data were available for all cases and were based on the National Cancer Registry, with a median observation time of 120 months (Interquartile Range (IQR) 80.9–144.7). Missing blood test data were supplemented using the Nearest Neighbor Imputation, and the Cox Proportional Hazards Regression model was used for analysis. The median age was 68.8 years (IQR 63.3–73.5). The five-year overall survival was 82.8%, and 508 patients were alive at the time of analysis. The median time between blood tests and the first day of radiotherapy was 6 days (IQR 0–19). HGB (p = 0.009) and AMC (p = 0.003) were independent prognostic factors for survival, along with age, Gleason Grade Group, clinical T stage and maximum prostate-specific antigen concentration. This study demonstrates that HGB and AMC can be useful biomarkers for overall survival in patients treated with radiotherapy for localized intermediate- or high-risk PCa.
    Type of Medium: Online Resource
    ISSN: 2227-9059
    Language: English
    Publisher: MDPI AG
    Publication Date: 2022
    detail.hit.zdb_id: 2720867-9
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  • 7
    In: Diagnostics, MDPI AG, Vol. 13, No. 18 ( 2023-09-08), p. 2887-
    Abstract: Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) is a well-known oncogene with a high prevalence of mutation in breast cancer patients. The effect of the mutation is a deregulation in phosphatidylinositol 3-kinase-related pathways, and, consequently, in unrestricted cell growth and differentiation. With the advent of precision oncology, PIK3CA has emerged as a pivotal treatment target, culminating in the recent approval of alpelisib. Despite years of research on this genetic alteration, certain aspects of its influence on the prognosis of breast cancer remain ambiguous. The purpose of this analysis is to characterize the clinical picture of breast cancer patients with PIK3CA mutation in comparison to the PIK3CA-wild-type group. We examined 103 tumor samples from 100 breast cancer patients using a next-generation sequencing panel. Presence of the mutation was linked to an older age at diagnosis, a lower expression of Ki67 protein, a greater percentage of tumors expressing progesterone receptors, and a notably higher incidence of metastatic disease at presentation. No significant differences were identified in overall and progression-free survival between the two groups. Our findings enhance the understanding of how PIK3CA mutations shape the clinical and prognostic landscape for breast cancer patients.
    Type of Medium: Online Resource
    ISSN: 2075-4418
    Language: English
    Publisher: MDPI AG
    Publication Date: 2023
    detail.hit.zdb_id: 2662336-5
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  • 8
    Online Resource
    Online Resource
    MDPI AG ; 2019
    In:  Materials Vol. 12, No. 21 ( 2019-10-30), p. 3567-
    In: Materials, MDPI AG, Vol. 12, No. 21 ( 2019-10-30), p. 3567-
    Abstract: Carbon nanotubes have been intensively researched for many years because of a wide array of promising properties that they have. In this paper, we present the impact of synthesis parameters on thermoelectric properties of nanocarbon material. We conducted a number of syntheses of multi-walled carbon nanotubes (MWCNTs) at different temperatures (800 and 900 °C) using various amounts of catalyst (2%, 5.5%, and 9.6%) to facilitate the process. We also tested the influence of injection rate of precursor and the necessity of material purification on thermoelectric properties of MWCNTs. The electrical conductivity, thermal conductivity, and Seebeck coefficient were measurement for all samples. Based on these parameters, the values of Power Factor and Figure of Merit were calculated. The results show that the most important parameter in the context of thermoelectric properties is purity of employed MWCNTs. To obtain appropriate material for this purpose optimum synthesis temperature and appropriate content of the catalyst must be selected. The study also reveals that post-synthetic purification of nanocarbon is essential to produce an attractive material for thermoelectrics.
    Type of Medium: Online Resource
    ISSN: 1996-1944
    Language: English
    Publisher: MDPI AG
    Publication Date: 2019
    detail.hit.zdb_id: 2487261-1
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  • 9
    In: Nutrients, MDPI AG, Vol. 12, No. 9 ( 2020-08-27), p. 2614-
    Abstract: Periodontitis is a chronic multifactorial inflammatory disease that leads to the loss of supportive tissues around the teeth with gradual deterioration of masticatory function and esthetics, resulting eventually in the decrease of the life quality. Host immune response triggered by bacterial biofilm is responsible for the chronic periodontal inflammation and ongoing tissue loss. Omega-3 polyunsaturated fatty acids (PUFA) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have anti-inflammatory properties, thus may be used for the treatment of chronic inflammatory diseases. In this study, we aimed to evaluate the effect of dietary supplementation with omega-3 PUFA in the patients with stage III and IV periodontitis. Thirty otherwise healthy patients were treated with scaling and root planning (SRP). In the test group (n = 16), patients were additionally supplemented with 2.6 g of EPA and 1.8 g of DHA. In the control group (n = 14), patients received only SRP. Periodontal examination was performed at baseline and three months following initial therapy. Salivary samples were taken twice at baseline and at the end of the experiment. We found that there was a statistically significant reduction in the bleeding on probing (BOP) and improvement of clinical attachment loss (CAL) at three months in the test group compared to the control group. Moreover, a statistically significant higher percentage of closed pockets (probing depth ≤ 4 mm without BOP) was achieved in the test group vs. control group after three months of treatment. Accordingly, the levels of pro-inflammatory cytokines/chemokines interleukin (IL)-8 and IL-17 were markedly lower, while the level of anti-inflammatory IL-10 was significantly higher in the salivary samples of the patients supplemented with omega-3 PUFA at three months in comparison to the patients treated with SRP alone. Our findings demonstrate that dietary intervention with high-dose of omega-3 PUFA during non-surgical therapy may have potential benefits in the management of periodontitis.
    Type of Medium: Online Resource
    ISSN: 2072-6643
    Language: English
    Publisher: MDPI AG
    Publication Date: 2020
    detail.hit.zdb_id: 2518386-2
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  • 10
    In: Radiotherapy and Oncology, Elsevier BV, Vol. 183 ( 2023-06), p. 109632-
    Type of Medium: Online Resource
    ISSN: 0167-8140
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2023
    detail.hit.zdb_id: 1500707-8
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