Relevant bibliographies by topics / Surface activity

Academic literature on the topic 'Surface activity'

Author: Grafiati
Published: 4 June 2021
Last updated: 25 May 2024

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Journal articles on the topic "Surface activity"

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Haliarnyk, D. M., D. S. Brychka, O. M. Bakalinska, and M. T. Kartel. "The catalytic activity of carbon nanomaterials in lauroyl peroxide decomposition reaction." Surface 8(23) (December 30, 2016): 137–46. http://dx.doi.org/10.15407/surface.2016.08.137.

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Voitko, K. V., O. M. Bakalinska, and M. T. Kartel. "Decomposition of peroxides by carbon nanotubes: factors, determining their catalytic activity." Surface 10(25) (December 30, 2018): 228–44. http://dx.doi.org/10.15407/surface.2018.10.228.

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Bogatyrov, V. M., O. I. Oranska, M. V. Galaburda, L. O. Yakovenko, K. S. Tsyganenko, Ya I. Savchuk, and O. M. Zaichenko. "Influence of aging under the light on the fungicidal activity of silvercontaining silica nanocomposites." Surface 8(23) (December 30, 2016): 259–66. http://dx.doi.org/10.15407/surface.2016.08.259.

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MATUURA, Ryohei. "Surface Activity and Surface Active Agent." Journal of Japan Oil Chemists' Society 34, no. 1 (1985): 67–71. http://dx.doi.org/10.5650/jos1956.34.67.

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Borysenko, M. V., L. I. Borysenko, V. P. Klius, S. V. Klius, and V. I. Shynkarenko. "Pyrolysis regeneration of activated carbon used for glycerin purification." SURFACE 14(29) (December 30, 2022): 95–100. http://dx.doi.org/10.15407/surface.2022.14.095.

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In this work, we investigated granular activated carbons Norit 1240 (AC) – initial and spent (SAC) with adsorbed impurities after purification of technical glycerin and subsequent washing with water. The aim of the work was to establish the optimal conditions for the thermal regeneration of AC at the pyrolysis unit and to quantify the adsorbed impurities in the SAC using thermogravimetric analysis (TGA). For all AC samples, the specific surface area (S), adsorption activity on iodine and mass fraction of moisture were measured. It was established by the TGA method that water is released in the temperature range of 20 – 180 °C, and glycerin – 180 – 400 °C. Spent AC contains up to 31.3 wt. % H2O and up to 37.3 wt. % C3H5(OH)3. The pyrolysis reactor was used for the regeneration of SAC samples. It was shown that after the reactivation of SACs, their specific surface area is restored to 45-94% of the initial one. There is a weak correlation between S and iodine number, R=0.64. Adsorption activity for iodine and S increase in the same row ACspent > ACregenerated > ACinitial. As a result of regeneration, activated carbons suitable for reuse were obtained.
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Ringer, Simon P. "Activity at the surface." Nature Materials 17, no. 1 (December 19, 2017): 10–12. http://dx.doi.org/10.1038/nmat5058.

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Rybal'chenko, V. K., V. S. Sedov, A. M. Shamonina, and I. L. Reshetnyak. "Surface activity of angiotensin." Bulletin of Experimental Biology and Medicine 116, no. 1 (July 1993): 826–27. http://dx.doi.org/10.1007/bf00786163.

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Nonomura, Yoshimune, and Shigeyuki Komura. "Surface activity of solid particles with extremely rough surfaces." Journal of Colloid and Interface Science 317, no. 2 (January 2008): 501–6. http://dx.doi.org/10.1016/j.jcis.2007.09.066.

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Voitko, K. V., O. M. Bakalinska, Yu V. Goshovska, Yu I. Sementsov, and M. T. Kartel. "Catalase-like properties of multilayer graphene oxides and their modified forms." Surface 12(27) (December 30, 2020): 251–62. http://dx.doi.org/10.15407/surface.2020.12.251.

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The catalytic system, that mimets catalase enzyme such as “multilayer graphene oxide /peroxide molecule” in aqueous media was investigated. The main factors that influence on catalyst’s effectiveness were determining. The catalytic activity of as-synthesized multilayered graphene oxides, and their modified forms (oxidized and nitrogen doped) were investigated in the decomposition of hydrogen peroxides at room temperature and physiological pHs by measuring the volume of released gases. A phosphate buffer with a pH of 5 to 8 was chosen as the reaction medium. The original and modified samples were characterized using XPS, TPD-MS, Boehm titration analyses. The effect of surface chemistry on the catalytic reaction proceeding has been studied. It was found that catalysis on the graphene plane is determined by the presence of heteroatoms in their structure. The catalytic process takes place in the kinetic zone over the entire accessible surface of the samples. The active sites of the catalysts contain a large amount of both nitrogen and oxygen-containing functional groups. In addition, the surface of graphene oxide is hydrophilic, which enhances the catalytic reaction in an aqueous medium. It has been established that the rate of hydrogen peroxide decomposition by reduced graphene oxide samples is lower than for samples modified with oxygen and nitrogen. The catalase-like activity of graphene increases in alkaline pH up to 7.8. Studies have shown that samples of multilayer graphenes with a high content of functional groups can be an alternative to the catalase enzyme as a catalyst for the decomposition of hydrogen peroxide in physiological solutions.
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Zheleznyak, А. R., О. М. Bakalinska, А. V. Brichka, G. O. Kalenyuk, and М. Т. Каrtel. "Properties, production methods and use of tin nanoxide." Surface 12(27) (December 30, 2020): 193–230. http://dx.doi.org/10.15407/surface.2020.12.193.

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The prevalence of tin compounds, economic affordability and non-toxicity determine its wide range of applications. Modern scientific literature on the properties, methods of preparation and application of tin nanooxide is analyzes in review. Its main characteristics and structural features are described. The ability of tin cations to be in two oxidation states, the ease of reduction of Sn+4 to Sn+2 and reverse oxidation, determines the redox properties of the SnO2 surface. In addition to stable oxides Sn4+ and Sn2,+ the existence of a homologous series of Snn+1O2n metastable compounds is assumed. It is proved that four-coordinated Sn+2 cations on the SnO2 surface can coexist only with oxygen vacancies in the immediate environment. Such cationic sites have the properties of strong Lewis acids and are highly reactive. Computer simulation of the SnO2 crystal surface allows us to propose a number of catalytic activity of SnO2 surfaces: (110) < (001) < (100) < (101). Preparation methods and synthesis parameters (nature and type of precursor, stabilizing agent and solvent, duration and temperature of the reaction, pH of the reaction mixture, etc.) determine the physicochemical properties of nanoparticles (shape, size, morphology and degree of crystallinity). The main (sol-gel, precipitation and coprecipitation, CVD, spray pyrolysis, hydrothermal, “green”) and less common (detonation, electric discharge) methods of nano-SnO2 obtaining are analyzed in the work. A variety of methods of synthesis and conditions makes it possible to obtain SnO2 nanoparticles with desired properties, which determine the activity of tin oxide in redox reactions, namely: nanosize and morphology of particles with prevalence of the most reactive faces - (100) і (101). Among the methods that do not require complex hardware design, one can dwell on the methods of sol-gel, "green" and coprecipitation. Tin oxide is traditionally used as an abrasive for polishing metal, glass and ceramic products. The transition to nanosized particles allows this material to reversibly absorb and release oxygen, which has determined its use in the design of gas-sensitive and biosensors, the creation of solar cells, fuel cells, lithium-ion batteries, oxidation catalysts, transparent and photoconductors. The multivalence and the presence of oxygen vacancies on the surface of tin oxide nanoparticles, the ease and speed of penetration into the cell membrane give nano-SnO2 properties of medicinal preparations, which makes it possible to use it in biomedical technologies for the treatment of diseases associated with oxidative stress lesions. The size, concentration of nanoparticles and modification of their surface are the key factors of influence, which usually intensify the antimicrobial, antibacterial, antitumor and antioxidant activity of the material.
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Dissertations / Theses on the topic "Surface activity"

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JABBARI, SARAH. "Origin of solar surface activity and sunspots." Licentiate thesis, Stockholms universitet, Institutionen för astronomi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-103637.

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In the last few years, there has been significant progress in the development of a new model for explaining magnetic flux concentrations, by invoking the negative effective magnetic pressure instability (NEMPI) in a highly stratified turbulent plasma. According to this model, the suppression of the turbulent pressure by a large-scale magnetic field leads to a negative contribution of turbulence to the effective magnetic pressure (the sum of non-turbulent and turbulent contributions). For large magnetic Reynolds numbers the negative turbulence contribution is large enough, so that the effective magnetic pressure is negative, which causes a large-scale instability (NEMPI). One of the potential applications of NEMPI is to explain the formation of active regions on the solar surface. On the other hand, the solar dynamo is known to be responsible for generating large-scale magnetic field in the Sun. Therefore, one step toward developing a more realistic model is to study a system where NEMPI is excited from a dynamo-generated magnetic field. In this context, the excitation of NEMPI in spherical geometry was studied here from a mean- field dynamo that generates the background magnetic field. Previous studies have shown that for NEMPI to work, the background field can neither be too weak nor too strong. To satisfy this condition for the dynamo-generated magnetic field, we adopt an “alpha squared dynamo” with an α effect proportional to the cosine of latitude and taking into account alpha quenching. We performed these mean-field simulations (MFS) using the Pencil Code. The results show that dynamo and NEMPI can work at the same time such that they become a coupled system. This coupled system has then been studied separately in more detail in plane geometry where we used both mean-field simulations and direct numerical simulations (DNS). Losada et al. (2013) showed that rotation suppresses NEMPI. However, we now find that for higher Coriolis numbers, the growth rate increase again. This implies that there is another source that provides the excitation of an instability. This mechanism acts at the same time as NEMPI or even after NEMPI was suppressed. One possibility is that for higher Coriolis numbers, an α2 dynamo is activated and causes the observed growth rate. In other words, for large values of the Coriolis numbers we again deal with the coupled system of NEMPI and mean-field dynamo. Both, MFS and DNS confirm this assumption. Using the test-field method, we also calculated the dynamo coefficients for such a system which again gave results consistent with previous studies. There was a small difference though, which is interpreted as being due to the larger scale separation that we have used in our simulations. Another important finding related to NEMPI was the result of Brandenburg et al. (2013), that in the presence of a vertical magnetic field NEMPI results in magnetic flux concentrations of equipartition field strength. This leads to the formation of a magnetic spot. This finding stimulated us to investigate properties of NEMPI for imposed vertical fields in more detail. We used MFS and DNS together with implicit large eddy simulations (ILES) to confirm that an initially uniform weak vertical magnetic field will lead to a circular magnetic spot of equipartition field strength if the plasma is highly stratified and scale separation is large enough. We determined the parameter ranges for NEMPI for a vertical imposed field. Our results show that, as we change the magnitude of the vertical imposed field, the growth rate and geometry of the flux concentrations is unchanged, but their position changes. In particular, by increasing the imposed field strength, the magnetic concentration forms deeper down in the domain.
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Delahooke, Diane Mary. "The biological activity of Bacteroides surface polysaccharides." Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/21194.

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Lipopolysaccharide (LPS), a major constituent of Gram-negative bacteria, is implicated as the key factor in the development of the Systemic Inflammatory Response Syndrome (SIRS). LPS can arise from an underlying bacteraemia, but given that the majority of patients with SIRS have no detectable bacteraemia, then LPS derived from the gut must be considered. Bacteroides species outnumber the enterobacteria such as E.coli in the gut by approximately 1000-fold. Although Bacteroides LPS is less endotoxic, by simple arithmetic there must be as much biological potential from the LPS of Bacteroides as from E.coli. This thesis re-examines the biological activity of Bacteroides LPS and its possible role in the development of SIRS. LPSs were extracted from seven Bacteroides species by three different techniques: the phenol-water (PW), the phenol-chloroform-petroleum (PCP) and Triton-Mg2+. The biological activity of these Bacteroides LPSs was compared to that of an E.coli O18K- LPS control. In general, Bacteroides LPSs prepared by the PW method were found to have a significantly higher activity in a mouse lethality model, LAL assay, TNF and IL-8 induction assays, than LPS extracted by the PCP or Triton methods. Bacteroides LPS extracted by the PCP method had consistently low activity in all assays. LPS from B.fragilis NCTC 9343 and B.caccae had a consistently higher activity than LPS from B.vulgatus and B.thetaiotaomicron in most assays. Differences in activity between B.fragilis NCTC 9343 LPS grown in different media was seen. The PW method selected for greater amounts of carbohydrate and KDO and the PCP the least. Further information from sub-population studies, Percoll profiles, chemotype on PAGE and chemical analysis failed to account for differences in biological activity between extraction methods and Bacteroides species.
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Elfakhri, S. O. "Antibacterial activity of novel self-disinfecting surface coatings." Thesis, University of Salford, 2014. http://usir.salford.ac.uk/33219/.

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The antibacterial activities of different thin films (TiO2/CuO, Cu/SiO2 and Ag/SiO2) prepared by flame-assisted chemical vapour deposition (FACVD) and atmospheric pressure thermal (APT-FCVD) for TiO2/CuO films, were investigated against standard strains of bacteria used for disinfectant testing and against multi-antibiotic resistant bacteria that have been shown to persist in the hospital environment. These included; MRSA strains (EMRSA15 and two recent clinical isolates MRSA 1595 and MRSA 1669), extended spectrum β-lactamase (ESBL) producing Escherichia coli, a second (ESBL- 2 ) producing Escherichia coli, KPC+ (carbapenemase producing) Klebsiella pneumoniae, Stenotrophomonas maltophilia, Acinetobacter baumannii, Listeria monocytogenes, Salmonella enterica ser typhimurium, and vancomycin resistant Enterococcus faecium (VRE) . The Antimicrobial activity of the above coatings (Cu/SiO2 and Ag/SiO2) was investigated based on the BS ISO 22196:2009 and 2011 Plastics – Measurement of antibacterial activity on plastics and other porous surfaces. The activity of TiO2/CuO films was investigated based on the BS ISO 27447:2009 Test method for antibacterial activity of semiconducting photocatalytic materials. On the TiO2/CuO films, the bacteria were killed by UVA irradiation of the photocatalyst with a >5 log kill within 4-6 h except for the MRSA where a 2.3 log kill was obtained after 6 h increasing to >5 log after 24 h. There was antimicrobial activity in the dark which was enhanced by irradiation with fluorescent light. There was also activity at 5ºC under UVA but activity was lower when fluorescent light was used for illumination. The Cu/SiO2 coating showed a >5 log reduction in viability after 4 h for the disinfectant test strain (E.coli) and for some pathogenic strains include; Acinetobacter baumannii, Klebsiella pneumoniae and Stenotrophomonas maltophilia. However, their activity against the other hospital isolates was slower but still gave a >5 log reduction for extended spectrum β-lactamase producing Escherichia coli and Salmonella enterica typhimurium, and > 2.5 log reduction for vancomycin resistant Enterococcus faecium, Listeria and methicillin resistant Staphylococcus aureus within 24 h. The coating was also active at 5ºC but was slow compared to room temperature. The highest activity of copper /silica films was seen at 35ºC, but bacterial cells were also killed on the control surfaces. The Ag/SiO2 coating was also active against pathogenic bacteria; however the coating was not hard or durable as other coatings used. The activity on natural contamination in an in use test in a toilet facility was also determined for coated ceramic tiles (Cu/SiO2 and Ag/SiO2) and coated steel. The results demonstrated that the tiles were highly active for the first 4 months period and the contamination was reduced by >99.9%. However, tiles lost some of their activity after simulated ageing and washing cycles. The Cu/SiO2 coated ceramic tiles placed in Manchester Royal Infirmary also showed antimicrobial activity and no indicator organisms were detected. The coatings had a good activity against both standard test strains and clinical isolates. The coatings (copper surfaces in particular), may have applications in health care by maintaining a background antimicrobial activity between standard cleaning and disinfection regimes. They may also have applications in other areas where reduction in microbial environmental contamination is important, for example, in the food industry. However, the optimum composition for use needs to be a balance between activity and durability. Keywords: TiO2, CuO, Ag, Antimicrobial; Chemical vapour deposition; Copper; Disinfection surface; Pathogenic bacteria (hospital pathogen).
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Berg, S. (Sonja). "Characterization and activity of surface plasmon resonance materials." Master's thesis, University of Oulu, 2017. http://urn.fi/URN:NBN:fi:oulu-201711083053.

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The goal of this study was to obtain new information about possibilities to utilize carbon dioxide (CO₂) with photocatalytic activation and reduction by using surface plasmon resonance titanium dioxide based materials decorated with platinum group metals. Carbon dioxide is known to be one of the most common greenhouse gases (GHG) and having a major impact on ongoing global warming. By utilizing CO₂ it is possible to mitigate CO₂ emissions and produce new sustainable fuels. This study included characterization of the prepared palladium (Pd) and platinum (Pt) decorated catalysts and testing their photocatalytic properties in carbon monoxide (CO) oxidation and CO₂ activation reactions under visible light and under irradiation of specific wavelength. In addition to different irradiation also different feed gas combinations were tested in both reactions. Characterization of prepared materials was done with XRD to study the crystalline structure and composition, BET-BJH to get information about the surface area and pore sizes, and TEM for surface structure analyses and distribution of metal decoration. Photocatalytic activity was studied with FT-IR DRIFT analyses with external solar light source and equipped with filters to control the wavelength of irradiation. The results of the characterization showed that preparation of the catalysts was successful. Photocatalytic activity results showed that some of the tested materials are able to oxidise CO and activate CO₂ in the presence of irradiation. Obtained results show that palladium and platinum decorated TiO₂ based materials could possibly be used in surface plasmon enhanced photocatalytic CO₂ reduction successfully
Työn tarkoituksena on selvittää hiilidioksidin (CO₂) hyödyntämisen mahdollisuutta valokatalyyttisellä aktivoinnilla ja pelkistämisellä käyttäen pintaplasmonisesti resonoivia jalometalleja sisältäviä titaanidioksidimateriaaleja. Hiilidioksidin tiedetään olevan yksi yleisimmistä kasvihuonekaasuista ja näin ollen sillä on suuri vaikutus meneillään olevaan ilmaston lämpenemiseen. Hyödyntämällä hiilidioksidia on mahdollista vähentää hiilidioksidipäästöjä ja kehittää uusia kestäviä polttoaineita. Tämä tutkimus sisältää valmistettujen platina- ja palladium-titaanidioksidi-katalyyttien karakterisointia ja niiden valokatalyyttisten ominaisuuksien tutkimista hiilimonoksidin (CO) hapettamisessa ja hiilidioksidin (CO₂) aktivoinnissa näkyvällä valolla ja valituilla valon aallonpituuksilla. Käytettyjen säteilyalueiden lisäksi myös erilaisia syöttökaasun yhdistelmiä tutkittiin molemmissa reaktioissa. Valmistettujen katalyyttien karakterisoinnit tehtiin XRD:llä, jolla saatiin tietoa materiaalien kiderakenteesta ja koostumuksesta, BET/BJH-menetelmällä jolla määritettiin pinta-alat ja huokostilavuudet sekä TEM mikroskopialla, jolla tarkasteltiin pinnan rakenteita ja metallin jakautumista katalyytin pintaan. Valokatalyyttistä aktiivisuutta tutkittiin DRIFT-mittauksin, joissa käytettiin ulkoista valonlähdettä ja erillisiä valosuodattimia, jotta eri aallonpituuksien vaikutusta reaktioon voitiin tutkia tarkemmin. Karakterisointien tulokset osoittivat materiaalien valmistuksen olleen onnistunut. Valokatalyyttisten aktiivisuuskokeiden tutkimustuloksista saatiin selville, että osa palladiumia tai platinaa sisältävistä titaanidioksidimateriaaleista kykeni hapettamaan hiilimonoksidia sekä aktivoimaan hiilidioksidia valosäteilyn avulla. Saadut tutkimustulokset osoittavat, että TiO₂ pohjaisia katalyyttejä platina- ja palladiumlisäyksillä voidaan mahdollisesti käyttää pintaplasmonisella värähtelyllä tehostetussa valokatalyysissä hiilidioksidin pelkistämiseksi
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Stiltner, Bridgett, and Phillip R. Scheuerman. "Microbial Enzyme Activity in Surface Water and Sediments." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/2958.

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Berkebile, Abigail Rae. "Airway surface liquid antiviral activity in cystic fibrosis." Thesis, University of Iowa, 2015. https://ir.uiowa.edu/etd/2045.

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Cystic fibrosis (CF) is a lethal genetic disease that affects 30,000 people in the United States alone. While the disease affects organs throughout the body, it is the lung disease that is the primary cause of morbidity and mortality for people with the disease. CF lung disease is characterized by thick and sticky mucus that obstructs the airways, acute and chronic bacterial infections, and chronic inflammation and remodeling. Thanks to the creation of the CF pig, it is now possible to study the manifestations of CF lung disease at birth. The CF pig develops spontaneous lung disease, similar to that found in humans with CF, making it the ideal model for our studies. One of the critical findings that revealed in studies of the CF pig is that airway surface liquid (ASL) bactericidal activity is impaired in CF at birth, and this activity is pH dependent. Because infants and children with CF tend to suffer greater morbidity from respiratory viruses than non-CF infants and children, we sought to determine if ASL has antiviral activity and if that activity is reduced in newborn CF pigs. We found that pre-incubating either tracheal or nasal ASL from wild-type pigs reduced the infectivity of various recombinant viruses expressing an eGFP or GFP reporter gene. Those viruses include Sendai virus (SeV-eGFP), respiratory syncytial virus (RSV-GFP), the PR8 strain of influenza virus A (PR8-eGFP), and adenovirus (Ad-eGFP), indicating ASL has broad-spectrum antiviral activity. Nasal secretions from newborn CF pigs had strikingly reduced antiviral activity against SeV-eGFP and Ad-eGFP compared to nasal secretions from WT littermates. Unlike what was observed for ASL antibacterial activity, nasal secretion antiviral activity was not affected by pH, nor was it affected by bicarbonate concentration, one of the molecules that drives pH in the airways. However, when we mixed CF and WT nasal secretions at different ratios, we found the antiviral activity to follow a linear trend, with antiviral activity increasing as the percentage of WT nasal secretions increased. This suggests that one or more components of nasal secretions are found less abundantly in CF nasal secretions compared to WT nasal secretions, leading to reduced antiviral activity in CF. The CF pig has facilitated a much greater understanding of the early stages of CF lung disease. This model will allow us to determine what antiviral components are lacking in the CF airways and why they are reduced in CF.
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Outten, Alan Gerard. "Analysis of human muscle activity." Thesis, Imperial College London, 1997. http://hdl.handle.net/10044/1/7958.

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Popescu, Narcis Ioan. "Regulation of procoagulant activity of cell surface tissue factor." Oklahoma City : [s.n.], 2010.

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Hsu, Bryan Boen. "Investigation of microbicidal activity of surface-immobilized hydrophobic polycations." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/62728.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references.
Hydrophobic polycations have been shown to completely kill bacterial, fungal, and viral pathogens, on-contact. Herein we describe advances with this technology on two fronts: (1) innovation of a polycationic-derivative that simplifies the labor-intensive covalent-immobilization procedure, and (2) elucidation of the current mechanistic understanding of this phenomenon. First, we developed and characterized a novel polycationic polymer capable of crosslinking to cotton via activation with ultraviolet light. The resultant, covalently-immobilized, Nalkyl polyethylenimine (PEI) demonstrates complete bactericidal activity against S. aureus and E. coli (i.e., representative Gram-positive and Gram-negative bacteria, respectively). In addition, by utilizing light to activate the covalent cross-linking, this immobilization procedure is simpler and more versatile than similar chemically-attached bactericidal polycations. Second, we shed light onto how the coating inactivates microbial pathogens. Gramnegative and Gram-positive bacteria exposed to the polycationic coating revealed substantial structural deformation, which allowed for the leakage of their intracellular contents. Characterization of the enzymes leaked into solution from Gram-negative bacteria indicated a disproportionately greater damage done to the outer-membrane than the inner-membrane. In addition, the quantity of proteins leaked into solution showed striking similarity to results obtained from bacteria subjected to lysozyme/EDTA treatment (i.e., a traditional cell lysis technique that degrades the cellular wall). In total, these results suggest that it is this interaction between the polycation and cellular structure (i.e., outer membrane and cell wall) that ultimately compromises bacterial integrity. Expanding our investigation, we studied the effect of the polycationic coating on another membrane-enclosed microbe: the influenza virus. We found that the viral particles adhere to the polycationic coating, which results in a structural deformation, similar to that borne-out by bacteria. As a consequence, viral genomic material is leaked into solution, revealing the viruses' state of inactivation upon adherence to the coating.
by Bryan Boen Hsu.
S.M.
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Maringa, Audacity. "Electrode surface modification using metallophthalocyanines and metal nanoparticles : electrocatalytic activity." Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/d1017921.

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Metallophthalocyanines and metal nanoparticles were successfully synthesized and applied for the electrooxidation of amitrole, nitrite and hydrazine individually or when employed together. The synthesized materials were characterized using the following techniques: predominantly scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), electrochemistry and scanning electrochemical microscopy (SECM). Different electrode modification methods were used to modify the glassy carbon substrates. The methods include adsorption, electrodeposition, electropolymerization and click chemistry. Modifying the glassy carbon substrate with MPc (electropolymerization) followed by metal nanoparticles (electrodeposition) or vice versa, made a hybrid modified surface that had efficient electron transfer. This was confirmed by electrochemical impedance studies with voltammetry measurements having lower detection potentials for the analytes. This work also describes for the first time the micropatterning of the glassy carbon substrate using the SECM tip. The substrate was electrografted with 4-azidobenzenediazonium salt and then the click reaction was performed using ethynylferrocene facilitated by Cu⁺ produced at the SECM tip. The SECM imaging was then used to show the clicked spot.
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Books on the topic "Surface activity"

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Tsujii, Kaoru. Surface activity: Principles, phenomena, and applications. San Diego: Academic Press, 1998.

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C, Srivastava R. Surface activity in drug action. Amsterdam: Elsevier, 2005.

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Surface activity of petroleum derived lubricants. Boca Raton: Taylor & Francis, 2010.

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Pillon, Lilianna Z. Surface activity of petroleum derived lubricants. Boca Raton [Fla.]: Taylor & Francis, 2011.

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Pillon, Lilianna Z. Surface activity of petroleum derived lubricants. Boca Raton: Taylor & Francis, 2010.

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Jennifer, Bennett. Scratching the surface: Democracy, traditions, gender. Lahore: Heinrich Boll Foundation, 2007.

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1954-, Magdassi Shlomo, ed. Surface activity of proteins: Chemical and physicochemical modifications. New York: M. Dekker, 1996.

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Zike, Dinah. Discovering earth's landforms and surface features. Melrose, FL: Common Sense Press, 2002.

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Kanno, Yoshinori. Method for measuring surface activity of silicon nitride powder. Washington DC: National Aeronautics and Space Administration, 1985.

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Taylor, Scott L., Wanda L. Davis, and Cailin Clarke. Trip under the surface. Toronto: GTK Press, 2004.

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Book chapters on the topic "Surface activity"

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Owen, Michael J. "Siloxane Surface Activity." In Advances in Chemistry, 705–39. Washington, DC: American Chemical Society, 1989. http://dx.doi.org/10.1021/ba-1990-0224.ch040.

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Wormser, Uri, Berta Brodsky, Eldad Victor Moor, Arie Eldad, Rivka Gal, Abraham Nyska, and Ron Kohen. "Skin Surface Proteolytic Activity." In Aspartic Proteinases, 207–12. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-5373-1_29.

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Rodonò, Marcello. "Small Scale Stellar Surface Structures." In Activity in Cool Star Envelopes, 105–6. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-2951-7_18.

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Pancholi, Vijaykumar. "Staphylococcal Extracellular/ Surface Enzymatic Activity." In Infectious Agents and Pathogenesis, 137–53. Boston, MA: Springer US, 2001. http://dx.doi.org/10.1007/0-306-46848-4_8.

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Rau, G., and H. Reucher. "Muscular Activity and Surface EMG." In Biomechanics: Current Interdisciplinary Research, 27–35. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-011-7432-9_3.

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Simmons, John V. "Surface Activity, Emulsions & Detergency." In Science and the Beauty Business, 57–66. London: Macmillan Education UK, 1989. http://dx.doi.org/10.1007/978-1-349-19705-7_7.

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Theng, Benny K. G. "Surface Acidity and Catalytic Activity." In Clay Mineral Catalysis of Organic Reactions, 85–130. Boca Raton : CRC Press, Taylor & Francis Group, 2018.: CRC Press, 2018. http://dx.doi.org/10.1201/9780429465789-2.

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Skripchenko, G. B., E. V. Zvyagintseva, and Z. S. Smutkina. "Carbon Fibre Reactivity and Surface Activity." In MICC 90, 264–67. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3676-1_40.

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Sheu, Eric Y., M. M. De Tar, and D. A. Storm. "Surface Activity And Dynamics Of Asphaltenes." In Asphaltene Particles in Fossil Fuel Exploration, Recovery, Refining, and Production Processes, 115–22. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4615-2456-4_9.

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Nebe, J. G. Barbara, Frank Luethen, Regina Lange, and Ulrich Beck. "Cellular Activity and Biomaterial's Surface Topography." In THERMEC 2006, 517–22. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-428-6.517.

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Conference papers on the topic "Surface activity"

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Vaughan, A. S. "Polymer surfaces: Designing materials to prevent or withstand discharge activity." In IEE Colloquium on Surface Phenomena Affecting Insulator Performance. IEE, 1998. http://dx.doi.org/10.1049/ic:19980222.

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Sheu, Eric Y., and Michael B. Shields. "Asphaltene Surface Activity at Oil/Water Interfaces." In SPE International Symposium on Oilfield Chemistry. Society of Petroleum Engineers, 1995. http://dx.doi.org/10.2118/28995-ms.

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Martinez-Tarifa, J. M., A. Cavallini, G. C. Montanari, and L. A. Dissado. "Surface degradation on XLPE under PD activity." In 2009 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP). IEEE, 2009. http://dx.doi.org/10.1109/ceidp.2009.5377773.

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Nosal, Eva-Marie, and Miloslav Nosal. "Passive Acoustic Monitoring of Surface Vessel Activity." In ASME 2009 28th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/omae2009-80074.

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Monitoring human activity in remote marine areas is a challenging problem to which acoustic methods present a promising solution. This paper develops and demonstrates automated passive acoustic methods to estimate ranges to surface vessels using a single seafloor-mounted hydrophone. Surface vessels that use echosounders (to navigate or find fish, for example) are especially well suited for passive acoustic monitoring since they use high-energy, narrow-band, short-duration pulses. Examples of surface vessel ranges estimated using echosounder pulses recorded on a seafloor-mounted hydrophone are presented.
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Imai, Yasuyuki, Tatsuya Koga, Tomoji Takamasa, Koji Okamoto, and Susumu Uematsu. "Radiation Induced Surface Activity Phenomenon: 1st Report — Surface Wettability on Metal Oxides." In 10th International Conference on Nuclear Engineering. ASMEDC, 2002. http://dx.doi.org/10.1115/icone10-22747.

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Improving the limit of boiling heat transfer or critical heat flux requires that the cooling liquid can contact the heating surface, or a high-wettability, highly hydrophilic heating surface, even if a vapor bubble layer is generated on the surface. We investigated surface wettability using metal oxides irradiated by gamma rays in room condition. Contact angle, an indicator of macroscopic wettability, was measured by image processing of the images obtained by a CCD video camera. The results showed that the surface wettability on oxide metal pieces of titanium, zircalloy No. 4, SUS-304 and copper improved significantly by Radiation Induced Surface Activity (RISA) phenomenon. Highly hydrophilic conditions on the test pieces were achieved after 500 kGy irradiation of 60Co gamma ray.
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Carvalho, J. P. G., R. Ghose, and J. Borges. "Holocene Activity of the Porto Alto Fault, Portugal." In Near Surface Geoscience 2012 – 18th European Meeting of Environmental and Engineering Geophysics. Netherlands: EAGE Publications BV, 2012. http://dx.doi.org/10.3997/2214-4609.20143317.

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Gustafson, Robert, Marty Gustafson, Raymond French, and James Carter. "Simulants for Testing and Verifying Exploration Surface Activity." In Space 2006. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2006. http://dx.doi.org/10.2514/6.2006-7513.

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Munck, Kim, Bolette Dybkjaer Hansen, Nina Jacobsen, Louise Pedersen Pilgaard, Samuel Emil Schmidt, and Kasper Sorensen. "Body Surface Mapping of the Mechanical Cardiac Activity." In 2016 Computing in Cardiology Conference. Computing in Cardiology, 2016. http://dx.doi.org/10.22489/cinc.2016.193-348.

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Liu, Jingjing, Wei Liane, Bing Ning, and Ting Mao. "Work Surface Arrangement Optimization Driven by Human Activity." In 2021 IEEE Virtual Reality and 3D User Interfaces (VR). IEEE, 2021. http://dx.doi.org/10.1109/vr50410.2021.00049.

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Khanam, Farzana, Shadli Islam, Md Asadur Rahman, and Mohiuddin Ahmad. "Muscle activity estimation through surface EMG analysis during salat." In 2015 International Conference on Electrical Engineering and Information Communication Technology (ICEEICT). IEEE, 2015. http://dx.doi.org/10.1109/iceeict.2015.7307402.

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Reports on the topic "Surface activity"

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Goodman, D. W. Correlations between surface structure and catalytic activity/selectivity. Office of Scientific and Technical Information (OSTI), October 1992. http://dx.doi.org/10.2172/6971943.

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Goodman, D. W. Correlations between surface structure and catalytic activity/selectivity. Office of Scientific and Technical Information (OSTI), November 1990. http://dx.doi.org/10.2172/6243154.

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Goodman, D. Correlations between surface structure and catalytic activity/selectivity. Office of Scientific and Technical Information (OSTI), September 1989. http://dx.doi.org/10.2172/5261883.

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Kevan, S. D. Surface and interface electronic structure: Sixth year activity report. Office of Scientific and Technical Information (OSTI), January 1992. http://dx.doi.org/10.2172/6731142.

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Kevan, S. D. Surface and interface electronic structure: Three year activity report. Office of Scientific and Technical Information (OSTI), January 1992. http://dx.doi.org/10.2172/7075157.

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Gardin, Denis Emmanuel. Hydrogenation of nitriles on a well-characterized nickel surface: From surface science studies to liquid phase catalytic activity measurements. Office of Scientific and Technical Information (OSTI), December 1993. http://dx.doi.org/10.2172/10179358.

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Barnard, M. R., H. MacGregor, A. D. Michelson, and C. R. Valeri. Effects of Liquid Storage and Cryopreservation on Platelet Surface Glycoproteins, Light Scatter, and Procoagulant Activity. Fort Belvoir, VA: Defense Technical Information Center, May 1996. http://dx.doi.org/10.21236/ada360295.

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Kevan, S. Surface and interface electronic structure: Three year activity report, August 1, 1986--November 30, 1989. Office of Scientific and Technical Information (OSTI), January 1989. http://dx.doi.org/10.2172/6246671.

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Thurston, Alison, Karen Foley, Shelby Rosten, Susan Taylor, Robert Haehnel, and Robyn Barbato. Microbial activity in dust-contaminated Antarctic snow. Engineer Research and Development Center (U.S.), September 2023. http://dx.doi.org/10.21079/11681/47681.

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During weather events, particles can accumulate on the snow near the Pegasus ice and Phoenix compacted-snow Runways at the US McMurdo Station in Antarctica. The deposited particles melt into the surface, initially forming steep-sided holes, which can widen into patches of weak and rotten snow and ice. These changes negatively impact the ice and snow runways and snow roads trafficked by vehicles. To understand the importance of microbes on this process, we examined deposited dust particles and their microbial communities in snow samples collected near the runways. Snow samples were analyzed at the Cold Regions Research and Engineering Laboratory where we performed a respiration study to measure the microbial activity during a simulated melt, isolated microorganisms, examined particle-size distribution, and performed 16S rRNA gene sequencing. We measured higher levels of carbon dioxide production from a sample containing more dust than from a sample containing less dust, a finding consistent with viable dust-associated microbial communities. Additionally, eleven microorganisms were isolated and cultured from snow samples containing dust particles. While wind patterns and satellite images suggest that the deposited particles originate from nearby Black Island, comparisons of the particle size and chemical composition were inconclusive.
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Goodman, D. W. Correlations between surface structure and catalytic activity/selectivity. Progress report, January 1, 1992--December 31, 1992. Office of Scientific and Technical Information (OSTI), October 1992. http://dx.doi.org/10.2172/10107571.

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