Effect Of Ion Irradiation On The Structural Properties And Hardness Of A-c:h:si:o:f Films

Amorphous carbon-based thin films, a-C:H:Si:O:F, were obtained by plasma immersion ion implantation and deposition (PIIID) from mixtures of hexamethyldisiloxane, sulfur hexafluoride and argon. For PIIID the sample holder was biased with negative 25 kV pulses at 60 Hz. The main system parameter was the proportion of SF6 in the reactor feed, R-SF. To allow comparison to growth without intentional ion implantation, some films were also grown by plasma enhanced chemical vapor deposition (PECVD). The objectives were to investigate the effects of fluorine incorporation and ion implantation on the film's chemical structure, and principally on the surface contact angle, hardness and friction coefficient. Infrared and X-ray photo-electron spectroscopic analyses revealed that the films are essentially amorphous and polymer-like, and that fluorine is incorporated for any non-zero value of R-SF. Choice of R-SF influences film composition and structure but ion implantation also plays a role. Depending on R-SF, hydrophilic or hydrophobic films may be produced. Ion implantation is beneficial while fluorine incorporation is detrimental to hardness. For ion implanted films the friction coefficient falls about one third as R-SF is increased from 0 to 60%. Films prepared by PIIID without fluorine incorporation present fairly low friction coefficients and hardnesses greater than those of conventional polymers.59

Optical Emission Study Of Reaction Mechanisms In The Deposition Of Nitrogen-containing Amorphous Hydrogenated Carbon Films

An expansion approach that is very simple for arbitrary profiles is presented. This requires only the diagolization of a matrix to obtain the eigen values. A couple-mode theory for calculation of diffraction of incident energy through inhomogeneous media, including gratings, and dispersion of electromagnetic energy propagating in photonic media is presented. A recursive R-matrix approach that is much more stable than a transfer T approach has been used. A transmission diffraction from a seven layer-deep square array of dielectric cylinders is calculated.1341901190

Effect of ion irradiation on the structural properties and hardness of A-C:H:SI:O:F films

Amorphous carbon-based thin films, a-C:H:Si:O:F, were obtained by plasma immersion ion implantation and deposition (PIIID) from mixtures of hexamethyldisiloxane, sulfur hexafluoride and argon. For PIIID the sample holder was biased with negative 25 kV pulses at 60 Hz. The main system parameter was the proportion of SF6 in the reactor feed, R-SF. To allow comparison to growth without intentional ion implantation, some films were also grown by plasma enhanced chemical vapor deposition (PECVD). The objectives were to investigate the effects of fluorine incorporation and ion implantation on the film's chemical structure, and principally on the surface contact angle, hardness and friction coefficient. Infrared and X-ray photo-electron spectroscopic analyses revealed that the films are essentially amorphous and polymer-like, and that fluorine is incorporated for any non-zero value of R-SF. Choice of R-SF influences film composition and structure but ion implantation also plays a role. Depending on R-SF, hydrophilic or hydrophobic films may be produced. Ion implantation is beneficial while fluorine incorporation is detrimental to hardness. For ion implanted films the friction coefficient falls about one third as R-SF is increased from 0 to 60%. Films prepared by PIIID without fluorine incorporation present fairly low friction coefficients and hardnesses greater than those of conventional polymers59115th Latin American Workshop on Plasma Physics (LAWPP) / 21st IAEA TM on Research Using Small Fusion Devices (RUSFD)2014-01COSTA RICAUniv Nacl Costa Rica, Instituto Tecnologico Costa Rica; Ad Astra Rocket Co; Int Atom Energy AgcySan Jos

Intranasal oxygen reverses hypoxaemia in immobilised free-ranging capybaras (Hydrochoerus hydrochaeris)

Capybara (Hydrochoerus hydrochaeris) is the main host of tick-borne pathogens causing Brazilian spotted fever; therefore, controlling its population is essential, and this may require chemical restraint. We assessed the impact of chemical restraint protocols on the partial pressure of arterial oxygen (PaO2) and other blood variables in 36 capybaras and the effect of different flows of nasal oxygen (O2) supplementation. The capybaras were hand-injected with dexmedetomidine (5 μg/kg) and midazolam (0.1 mg/kg) and butorphanol (0.2 mg/kg) (DMB, n = 18) or methadone (0.1 mg/kg) (DMM, n = 18). One-third of the animals were maintained in ambient air throughout the procedure, and one-third were administered intranasal 2 L/min O2 after 30 min whereas the other third were administered 5 L/min O2. Arterial blood gases, acid-base status, and electrolytes were assessed 30 and 60 min after drug injection. The DMB and DMM groups did not vary based on any of the evaluated variables. All animals developed hypoxaemia (PaO2 44 [30; 73] mmHg, SaO2 81 [62; 93] %) 30 min before O2 supplementation. Intranasal O2 at 2 L/min improved PaO2 (63 [49; 97] mmHg and SaO2 [92 [85; 98] %), but 9 of 12 capybaras remained hypoxaemic. A higher O2 flow of 5 L/min was efficient in treating hypoxaemia (PaO2 188 [146; 414] mmHg, SaO2 100 [99; 100] %) in all the 12 animals that received it. Both drug protocols induced hypoxaemia, which could be treated with intranasal oxygen supplementation

Synthesis of multifunctional chlorhexidine-doped thin films for titanium-based implant materials

Our goal was to create bio-functional chlorhexidine (CHX)-doped thin films on commercially pure titanium (cpTi) discs using the glow discharge plasma approach. Different plasma deposition times (50, 35 and 20 min) were used to create bio-functional surfaces based on silicon films with CHX that were compared to the control groups [no CHX and bulk cpTi surface (machined)]. Physico-chemical and biological characterizations included: 1. Morphology, roughness, elemental chemical composition, film thickness, contact angle and surface free energy; 2. CHX-release rate; 3. Antibacterial effect on Streptococcus sanguinis biofilms at 24, 48 and 72 h; 4. Cytotoxicity and metabolic activity using fibroblasts cell culture (NIH-F3T3 cells) at 1, 2, 3 and 4 days; 5. Protein expression by NIH-F3T3 cells at 1, 2, 3 and 4 days; and 6. Co-culture assay of fibroblasts cells and S. sanguinis to assess live and dead cells on the confocal laser scanning microscopy, mitochondrial activity (XTT), membrane leakage (LDH release), and metabolic activity (WST-1 assay) at 1, 2 and 3 days of co-incubation. Data analysis showed that silicon films, with or without CHX coated cpTi discs, increased surface wettability and free energy (p 0.05), whereas cell metabolism (MTT assay) was affected by CHX, with the 35 min of plasma deposition time group displaying the lowest values as compared to bulk cpTi (p 0.05). Altogether, the findings of the current study support the conclusion that silicon films added with CHX can be successfully created on titanium discs and have the potential to affect bacterial growth and inflammatory markers without affecting cell viability/proliferation rates

Deciphering pyritization-kerogenization gradient for fish soft-tissue preservation.

Soft-tissue preservation provides palaeobiological information that is otherwise lost during fossilization. In Brazil, the Early Cretaceous Santana Formation contains fish with integument, muscles, connective tissues, and eyes that are still preserved. Our study revealed that soft-tissues were pyritized or kerogenized in different microfacies, which yielded distinct preservation fidelities. Indeed, new data provided the first record of pyritized vertebrate muscles and eyes. We propose that the different taphonomic pathways were controlled by distinct sedimentation rates in two different microfacies. Through this process, carcasses deposited in each of these microfacies underwent different residence times in sulphate-reduction and methanogenesis zones, thus yielding pyritized or kerogenized softtissues, and a similar process has previously been suggested in studies of a late Ediacaran lagerst?tte