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This study focuses on the antimicrobial effects in silver-indium-tantalum oxide (Ag–InTaO) thin films. A stack of alternated layers of Ag (7 ​nm), In2O3 (14 ​nm) and Ta2O5 (10 ​nm) was sequentially deposited by sputtering. Then this as-deposited stack of films was rapidly annealed at three selected temperatures 700, 800 or 900 ​°C for 5 ​min to allow the formation of complex oxides. Results from material characterization indicate that annealing help to form complex oxides, intermetallic compounds and Ag particles on the top surface. These features lead to the improved antimicrobial effect against E. Coli. under visible light by Ag–InTaO.

Both WO3 and NiO are known to be electrochromic materials. In this study, a stack of PET/IZO/WO3/Ta2O5/NiO/IZO electrochromic device (IZO: indium zinc oxide) was fabricated on polymeric substrate (polyethylene terephthalate, PET) by sputtering. Before stacking all layers, each material was separately deposited on a glass substrate under different oxygen flow rates and examined for their microstructures, compositions, optical properties and electrochromic functions. The selected oxygen flow rates have all deposited films to be amorphous except NiO with some crystallites. The electrochromism of WO3 and NiO was materialized by electrochemical insertion of cations (Li+) and electrons into WO3 and NiO films before subjected to potential statics and cyclic voltammetry. The coloration efficiency and transparency of films from these electrochemical tests were evaluated by UV–Vis-NIR spectroscopy. It was found that electrochromism is feasible between ±1 V with efficiency reaching 60 cm2/C in WO3 and 20 cm2/C in NiO, and optical transmittance between 65% - 80% in the range of visible light for films deposited under specific conditions. By analyzing and comparing the coloration efficiency and transparency from electrochemical tests, we can determined a feasible set of process parameters, i.e. oxygen flow rates for sputtering. These parameters then were used to fabricate the stack of PET/IZO/WO3/Ta2O5/NiO/IZO and its electrochromic function was successfully demonstrated.

This research aims to prepare macroporous Ag/TiO2 composite foams via particle-stabilized Pickering emulsion for bactericidal and photocatalytic activities. The Ag/TiO2 particles used for preparing the composite foams consisted of Ag core surrounded by mesoporous TiO2 shell. By selective adsorption of nonionic 1-hexadecylamine molecules on the Ag/TiO2 particles, an initially hydrophilic surface was tuned to partly hydrophobic with contact angle of ∼80°. Stable foams were then prepared by a simple mechanical frothing of aqueous suspensions consisting of the hydrophobic Ag/TiO2 particles as the filler phase, followed then by calcination to obtain the macroporous Ag/TiO2 foams. The composite foams impart photo-degradation capability against methylene-blue dye in water under ultraviolet irradiation. The composite foams also render a synergistic antimicrobial activity against Escherichia coli, in which the bactericidal efficiency reached 99% under dark conditions in 3 h.

TaO x N y films were deposited by reactive co-sputtering with various oxygen flow rates. After deposition, the films' structural and mechanical properties were examined. Then, the samples were tested for their biocompatibility and cell viability using 3T3 cells. With the increase of oxygen flow rate, the film transformed from crystalline TaN to crystalline TaON, eventually to amorphous Ta-oxide. The film deposited with 0.3 sccm oxygen flow rate has the highest hardness (H), modulus (E), and H/E ratio due to the substitution of nitrogen atoms with oxygen without changing the crystal structure. When the film was deposited with 0.9 sccm oxygen flow rate, the grain size and surface roughness reached the maximum value. Accordingly, this film had the highest biocompatibility and cell viability, while the film with high oxygen contents showed poor cell viability due to its low roughness and surface energy. It is shown TaOxNy films with tailored properties can be obtained as a function of oxygen flow rate set during deposition.

Mesoporous TiO 2 –Ag composite particles with raspberry-like morphology were prepared by a two-step chemical route and their photocatalytic and bactericidal properties were examined. Ag nanoclusters of about 50 nm in diameter were decorated on surface of submicrometer, anatase TiO 2 particles with Ag concentration of 3.8±0.4 at%; in which, the TiO 2 particles were mesoporous with an average pore diameter of 9.3 nm and a BET surface area of 147.5 m 2 g −1 . The composite particles enhanced the photocatalytic degradation of methylene blue (MB) dye in water under ultraviolet irradiation when compare to that of the bare TiO 2 . Removal of the MB dye with an initial concentration of 1×10 −5 M was completed within an hour and the degradation rate of the MB dye was found independent of temperature employed. In addition, the composite particles imparted bactericidal activity against gram-negative Escherichia coli in aqueous solutions under dark condition, enabling hence bifunctional activities under both light and dark situations.

Cu 2 O and Cu 2 O–Ag 2 O thin films were synthesized by a plasma oxidation process on uncoated as well as Cu and Cu–Ag(4 at.%) thin-film coated Cu sheets, using an inductively coupled plasma system equipped with four internal antennas. During oxidation, a plasma probe and an optical emission spectrometer were used to characterize the plasma with the variation of O 2 /(Ar + O 2 ) flow ratios. After oxidation, the structural phases and the growth rate of the oxidized layer were first examined. To compare the photo-electrical properties of Cu 2 O and Cu 2 O–Ag 2 O, the incident-photon-conversion-efficiency of the samples was measured. The results shows that the oxidation rate was increased with the increase of oxygen radicals (O*), which is attributed to the increase of plasma density. Deposited in low oxygen ratio, the oxidized films would have high deposition rate but with more complex structure. The coupling of Ag 2 O phase into Cu 2 O can enhance light absorption and create more electron–hole pairs due to the narrower band-gap structure of Ag 2 O. The effect of Ag 2 O phase on the enhanced photocurrent is discussed.

Tungsten oxide films under different oxygen flow rates are deposited by DC sputtering. The voltage change at target and analyses for the deposited films by X-ray diffraction, scanning electronic microscope, X-ray photoelectron spectroscopy and ultraviolet–visible-near infrared spectroscopy consistently indicate that low oxygen flow rate (5 sccm) only creates metal-rich tungsten oxide films, while higher oxygen flow rate (10–20 sccm) assures the deposition of amorphous WO3 films. To explore the electrochromic function of deposited WO3 films, we use electrochemical tests to perform the insertion of lithium ions and electrons into films. The WO3 films switch between color and bleach states effectively by both potentiostat and cyclic voltammetry. Quantitative evaluation on electrochemical tests indicates that WO3 film with composition close to its stoichiometry is an optimal choice for electrochromic function.

Hard TaN–(Ag,Cu) nanocomposite films were deposited on PEEK (polyether ether ketone) substrates using reactive co-sputtering. The films were then annealed using RTA (Rapid Thermal Annealing) at 200 °C to induce the nucleation and growth of soft metal particles in the TaN matrix and on the surface of the films. After examining the surface morphologies, structures, and mechanical properties of the samples, they were tested for their tribological properties under a normal load of 1 N or 5 N. It was found that the samples' tribological properties were much improved compared to uncoated PEEK, even though the substrate is relatively soft. This was especially apparent for heavier loads. Apparently, the solid lubricants (i.e., Ag and Cu particles) that emerged on coating's surface during the annealing process reduced the frictional force and wear rate of PEEK. These results were similar to those that were obtained using tool steel substrates. The coated samples were also tested for their anti-bacterial properties using Gram-negative Escherichia coli ( E. coli ) and Gram-positive Staphylococcus aureus ( S. aureus ) bacteria. It was found that the anti-bacterial efficiency of these samples was significant against both E. coli and S. aureus , even though the deposited samples were annealed through RTA at the relatively low temperature of 200 °C. There was no peeling found between coatings and PEEK substrates after tribological and scratch testings.

When two different oxides films stacked together, if the absorption (upper) layer has both its conduction and valence bands more negatively lower than that of the layer underneath, then the photo-excited electrons can be forwarded to the underneath layer to become an effect of energy storage. Recent studies discovered that the double-layers of Cu2O/TiO2 films possess such capacity. In order to investigate this specific phenomenon, we use a DC magnetron reactive sputtering to deposit a double-layer of Ag2O/TiO2 films on glass substrate. The film thicknesses of the double-layer are 300 nm and 200 nm respectively. X-Ray diffraction (XRD), scanning electron microscope (SEM) and UV–VIS–NIR photospectrometer and photoluminance tests were used to study the structure, morphology, optical absorption and band gaps of the stacked films. From XRD and SEM, we can confirm the microstructures of each layer. The UV–VIS–NIR spectrum revealed that the optical absorption of Ag2O/TiO2 fell in between the single film of Ag2O and TiO2. Further, two band gaps were estimated for Ag2O/TiO2 films based on the Beer-Lambert law and Tauc plot. Photoluminance and photoelectrochemical tests indicated that delayed emission by electron-hole recombination and photoelectrical current was effectively support the mechanism of electrons transfer from Ag2O to TiO2 at Ag2O/TiO2 interface in the double-layer films.

Amorphous hydrogenated silicon films were deposited on quartz substrates in an inductive coupled plasma-chemical vapor deposition system with four internal low inductance antennas units. Different Ar and hydrogen flow rates were tested for their influences on the structures of deposited films. For monitoring purposes, Langmuir probe and optical emission spectrometer were installed to detect the variation of electrical field in plasma during deposition. Data from Langmuir probe and optical emission spectrometer were analyzed subsequently. After deposition, the films were examined by X-ray diffraction and Raman spectrometer for their microstructures. Results indicate that under the supply of pure Ar flow, the deposition rate can be expedited to 3.5 nm/s and amorphous films were formed on quartz substrates. With the supply of mixed hydrogen and argon (Ar 15 sccm + H 2 50 sccm + SiH 4 50 sccm), the deposition rate can reach 4.5 nm/s. Although it is well known that a high supply of H 2 helps the formation of micro-crystalline silicon, these deposited hydrogenated Si films, confirmed by X-ray diffraction patterns and Raman spectroscopy, all maintained their amorphousness under various range of Ar and H 2 flow rates.

Tantalum oxynitride films were created by direct nitridation/oxidation during rapid thermal annealing at temperatures 450–700 °C. Instead of during deposition, this post process may be proved to be an alternative way to make transition metallic oxynitride films. With sufficient supply of oxygen flow (≥ 30 sccm), TaO x N y was formed as examined from X-ray diffraction (XRD) analysis. This oxynitride film has a broad optical absorption over the range of visible light and sufficient photocatalytic function. For optical absorption, the films' transmittance and reflectance were measured by a UV–VIS–NIR spectrophotometer with wavelengths ranging from 300 to 900 nm. The broad visible light absorption is associated with the formation of band gap in TaO x N y film, which was examined by the theoretical calculations combining the Beer–Lambert law and Tauc formula. Lastly, the photocatalysis of TaO x N y was gauged by the photodegradation test which measured the reduction of light absorbance affected by the decomposition of methylene blue (C 16 H 18 N 3 SCl.3H 2 O) on TaO x N y under visible light irradiation.

Silicon dioxide with embedded nano-size Ag particles has unique optical absorption due to the phenomenon known as surface plasmon resonance (SPR). SPR is the local resonance of conduction band electrons when excited by external optical fields. In this study, Ag/SiO 2 films with different Ag layers (3/5/7/10 nm) were deposited on glass sequentially by magnetron sputtering. The films then underwent the rapid thermal annealing (RTA) to create various sizes of silver particles. The RTA was carried out at elevated temperatures from 450 to 600 °C over different periods. All samples were examined by field-emission scanning electron microscope (FESEM) and surface profiler for their surface morphology. For optical properties, the films’ transmittance and reflectance were measured with wavelengths ranging from 300 to 900 nm by a UV–VIS–NIR spectrophotometer. Experimental results show that for longer annealing time (15 min) and thicker deposited Ag film, larger Ag particles can be produced. These larger Ag particles on SiO 2 surface serve as the resonators of electrons to result a broader absorption under the visible light irradiation. Following the experimental results, a newly proposed fitting scheme based on the Mie solution was tested and good fits to the experimental absorbance of different films were attained.

TaON–Ag nanocomposite thin films with Ag nano-particles embedded in TaON were prepared by reactive co-sputtering of Ta and Ag in the plasma of (O 2 + N 2 )/Ar. The deposition temperature was either at room temperature or 300 °C. These films were characterized mainly by UV–Vis photometry and scanning electron microscopy. It is found that Ag doping into the TaON films leads to several beneficial changes on film properties. It would reduce the optical band gap and, therefore, enhance the films' photocatalytic behavior. It is also found that Ag nano-particles may emerge on the surface of TaON with or without RTA. This could be much meaningful since Ag particles' appearance is closely related to the antibacterial property of TaON–Ag films. The results show that TaON–Ag films deposited at 300 °C have an outstanding antibacterial behavior with the illumination of visible light due to the synergistic effects of Ag and photocatalytic behavior of TaON.

An amorphous Ta-Zr binary alloy diffusion barrier was studied in the Cu metallization. A Cu/Ta 50 Zr 50 /SiO 2 /Si stack with 50 nm thick amorphous film was prepared by co-sputtering can effectively suppress the penetration of Cu atoms into substrate upon annealing up to 650 °C. Examining the thermal stability of the barrier revealed that the crystallization of these amorphous Ta 50 Zr 50 films occurred at 800 °C, higher than its failure temperature. The results show that the existence ofCu layer first induced the formation of TaSi 2 and ZrSi 2 crystalline phases at 650 °C, followed by the formation of Cu 3 Si. A failure mechanism of the diffusion barrier is proposed based on the relation between thermal stress and the activation energy of barrier/ substrate interface reaction.

Cu 2 O and two types of Cu 2 O–Ag–Cu 2 O (CAC) multilayered thin films were deposited on glass substrates using DC-magnetron sputtering. For CAC films, the mass thickness of Ag layer was controlled at 3 nm. After deposition, some of these films were annealed using a rapid thermal annealing (RTA) system at 650 °C, in order to create embedded Ag particles. AC films were used to study the clustering effect of Ag in Ar atmosphere, as well as for forming the 2nd type of CAC film by covering another Cu 2 O layer on the annealed AC structure. A UV–VIS–NIR photometer, a Hall measurement system, and a I–V measurement system were used to characterize the optical and electrical properties of these films with and without RTA. The results show that 2-dimensional Ag layer can transform into many individual particles due to its high surface tension at annealing temperature, no matter when the annealing was carried out. For CAC films, without annealing, the optical transmission and the resistivity are decreased with the inserted Ag layer. After annealing, both the transmission and resistivity are increased, possibly due to the clustering effect of Ag layer. Most importantly, it is found that the embedded Ag particles can increase the light absorption in the NIR–IR region, which can increase photo-induced current.

TaN-Cu nanocomposite films, were deposited by reactive co-sputtering on Si and tool steel substrates. The films were then annealed using RTA (Rapid Thermal Annealing) at 400 °C for 2, 4, 8 min respectively to induce the nucleation and growth of Cu particles in the TaN matrix and on the film surface. SSPM (Scanning Surface Potential Microscopy) and SEM (Scanning Electron Microscopy) were applied to examine the Cu nano-particles that emerged on the surface of TaN-Cu thin films. Pin-on-Disk tribometer was used to study the effect of annealing on the films' tribological properties. The results reveal that annealing by RTA can cause Cu nano-particles to emerge on the TaN surface. Consequently, hardness and friction coefficients will change depending on annealing conditions, Cu content, and/or Cu particle emergence.

Four kinds of alloy thin films were deposited on Si(100) by co-sputtering method with two kinds of metal targets to investigate the formation of boundary-free amorphous structure which may lead to featureless morphology. These thin films, Nb-Cr, Ta-Cr, Ti-Nb, and Zr-Cr, were examined using XRD SEM, XPS, TEM, and four-point probe for resistivity measurement. It was found that the forming ranges of amorphous thin films were related to the difference in atomic size of the paired metals as well as their heat of mixing. The addition of nitrogen gas during deposition caused further amorphization and reduced surface roughness, until nitride phases were formed. For Ta-Cr thin film, the boundary-free amorphous phase was generated with the composition between Ta-82% Cr and Ta-30% Cr. The composition region of the amorphous phase was explained in a ternary system. The barrier property of a Ta-Cr-N amorphous thin film was examined. It was found that a thin TaN layer controlled the reaction of Cr and Si and improved the barrier performance.

TaN-Cu nanocomposite thin films used as materials for thin-film resistors (TFR) were prepared by magnetron dc reactive co-sputtering. With the introduction of N2 gas flow into the Ar/N2 plasma, different phases of β-Ta, Ta2N, TaN, and Cu can be observed, resulting in different electrical properties of TaN-Cu thin films. After deposition, rapid thermal processing (RTP) was applied to anneal the thin films at 400 °C for 2, 4, 8 min in Ar ambient, causing the nucleation and growth of Cu nanoparticles. It was found that the resistivity and TCR changed after various annealing time due to the counteractions among the quantum effect caused by the nanosized Cu particles, the amorphous matrix, and loosened TaN matrix after Cu precipitation. The most obvious increase in the resistivity was found when annealing for 4 min, and the most decrease in TCR occurred after 4 min annealing. In general, a suitable combination of annealing time, Cu at.%, and N2 flow rate is required to reach near-zero TCR value. Longer annealing time requires less Cu at.% to reach zero-TCR point.

In reactive sputtering, the introduction of reactive gas would create a hysteresis transition from metal to compound mode in both the target and the substrate. The hysteresis transition is characterized by a sudden change in partial pressure, sputtering rate and fraction of compound formation, etc. Therefore, the stability is an important issue of process control. In this paper, a mathematical model with variable sticking coefficients based on surface kinetics is introduced to study the process stability. The variable sticking coefficient represents different mechanisms for surface reactions from the type of Langmuir to precursors. To facilitate the analysis, several nondimensional parameters are introduced and used for formulation. Results show that, when the chemical reaction on a substrate is moderate, a higher sputtering yield of the compound leads to a more stable steady-state at lower inflow rates. However, when the ratio of sputtering yield (compound/metal) is zero, there is no hysteresis transition because of the deposition of pure metal (single phase) on the substrate. For different sticking mechanisms, the precursor type is found to make the surface easier to saturate with compound due to its higher default sticking coefficient and the lower pressure and inflow rate for the hysteresis transition.

Although sputtered tantalum nitride film is commonly used as thin film resistor (TFR), it has the disadvantage of having negative temperature coefficient of resistivity (TCR). It is therefore thought that the incorporation of Cu can result in near-zero TCR TFRs. TaN–Cu nanocomposite thin films with copper as the nano-particles dispersed in tantalum nitride matrix were fabricated by d.c. reactive co-sputtering. After deposition, thin films were annealed using rapid thermal processing at 400 °C for 2, 4, and 8 min in Ar atmosphere, causing the emergence and growth of the Cu nano-particles. It is found that the emergence of Cu nano-particles can decrease or increase the TCR of TaN, depending on the particle size and Cu content. Strain gauge factors were evaluated on the films showing near-zero TCR behavior. The gauge factor was found affected by annealing and Cu concentrations. X-ray diffractometry (XRD), transmission electron microscopy (TEM), and high temperature four-point probe were used to characterize the microstructure and electrical properties of both as-deposited and annealed TaN–Cu thin films.

Simulation of a deformable vesicle by laser trapping in a Newtonian fluid is performed by the finite element analysis (FEA). The vesicle is modeled as a sphere with two incompressible, Mooney–Rivilin materials to represent the lipid bi-layer membrane and cytoskeleton of a cell. Several parameters such as the Reynolds number, the ratios of Young's modulus and Mooney–Rivilin coefficients are used for a systematic numerical study on the interaction between the fluid and vesicle. Results show that the vesicle deformation is highly localized near the laser-trapping region and it results in a local negative pressure gradient if the membrane's stiffness is low. Corresponding stress analysis also reveals that the deformation mechanism in membrane changes from bending to stretching along the circumferential direction. Finally, it is found that Mooney–Rivilin coefficients of cytoskeleton have a dominated influence on the part of non-linear deformation of vesicle if the stiffness of membrane is low.

In reactive sputtering, the introduction of a reactive gas can lead to a hysteresis transition from metal to compounds in both the target and substrate. The hysteresis transition is characterized by a sudden change in partial pressure, sputtering rate, fraction of compound formation, etc. Therefore, stability is an important issue in the process control. In this paper, a mathematical model with variable sticking coefficients based on surface kinetics is used to study the stability of the process. The variable sticking coefficient represents different mechanisms for surface reactions from the Langmuir to precursor type. In order to facilitate the analysis, several nondimensional parameters are identified and used for formulation. Results show that an unsteady system converges to a steady state relatively fast at low inflow rates. With an eigenvalue analysis, the range of positive eigenvalues is consistent with the presence of a hysteresis loop. It is also found that when the chemical reaction on the substrate is moderate, a higher sputter yield of the compound leads to a more stable steady state at lower inflow rates. Regarding the sticking mechanism, for the type of precursors with the parameter k < 1, the compound is easier to form and saturate on the surface due to the higher default sticking coefficient and the lower operating conditions for the hysteresis transition.

Several (Nb,Cr)N coatings were deposited by an unbalanced magnetron sputtering system. Following the deposition, the tribological properties of these coatings were studied using a ball-on-disk setup with alumina balls. The wear debris was then characterized using Raman spectroscopy to identify oxides generated during the wear process to gain a better understanding of tribochemical reactions. The results show that Cr2O3 and CrNbO4 constitute the debris obtained from Cr-rich coatings, while Nb2O5·nH2O is the major constituent of the debris formed on Nb-rich coatings. From the study of the debris, the difference in wear mechanism between Cr-rich and Nb-rich coatings is explained and confirmed.

Based on Berg's model for reactive sputtering, several nondimensional parameters and ratios are first identified in line with their physical significance. These parameters and ratios are subsequently used to analyze the steady-state solutions of reactive sputtering in detail. Results show that, when the chemical reaction in the substrate is moderate, the lower sputter yield of a compound enhances the hysteresis loop at higher inflow rates. However, when the ratio of sputtering yield (compound/metal) is zero, there is no hysteresis transition because of the deposition of pure metal (single phase) on the substrate. Hysteresis is influenced by pumping speed and a stability criterion is established based on the segment of s curve with negative slope. From the criterion, two turning points for the hysteresis loop can be easily found either graphically or algebraically.

An attempt was made to calculate the sputtering rate of a cathode during a plasma-assisted deposition or etching process. In this attempt, an approach combining sputtering models and Monte Carlo simulation was developed. By using a Cr target as an example, the approach was shown to be satisfactory.

Five graded (Ti x Cr 0.6− x )N 0.4 coatings were deposited by unbalanced magnetron sputtering. These coatings were first characterized using XRD, TMA, glow discharge spectroscopy and Raman, to understand their basic properties and oxidation resistance. The focus was then on the comparison of wear resistance among these coatings against epoxy molding compounds. The results show that the properties and wear resistance of the ternary coatings depend strongly on the composition ratio of Ti and Cr. Cromium remarkably enhances TiN coating's oxidation resistance and therefore, wear resistance against molding compound. All of the Ti–Cr–N ternary coating exhibit better wear performance against EMC than TiN coating.

In 35 adult cats anesthetized with intraperitoneal chloralose and urethane, the ventrolateral medulla was explored by microinjection of kainic acid (KA, 24 mM, 200 nl) with metal electrode-tubing or glass micropipette to determine regions which elicit persistent apnea. Persistent apnea is defined as: (1) In spontaneously breathing cats, termination of respiration over 3 min with a decrease of the mean systemic arterial pressure (MSAP) to 25 mm Hg. (2) In animals under artificial ventilation and paralyzed by gallamine, cessation of bilateral phrenic nerve (PNA) activities over 25 min. The apnea producing area was located dorsal to the rostral pole of the lateral reticular nucleus, ventromedial to the ambiguous nucleus and immediately caudal to the retrofacial nucleus. Functionally, this region includes the rostral part of the ventral respiratory group (rVRG) encompassing the pre-BOtzinger area. We define this region as the VRG apnea producing area (VRG-Apa). Fatal apneusis was observed under following conditions: (1) Persistent apnea was produced after a single KA microinjection in one side of the VRG-Apa (5 animals). Microinjection of sodium glutamate (0.25 M, 70-200 nl) in the same area produced only brief apnea, while microinjection of kynurenic acid (0.1 M, 200 nl) showed little effect on the respiration but slightly increased the SAP. (2) Positioning an electrode nearby but not in the VRG-Apa with or without KA injection did not produce apnea. But when a second electrode insertion to the opposite VRG-Apa immediately produced persistent apnea even without KA injection (6 animals). (3) Midsagittal division of the medulla 0-5 mm rostral to the obex produced persistent silence of PNA on both sides in artificial ventilated animals (7 animals), while similar division 0-5 mm caudal to the obex (4 animals) produced a brief but reversible quiescence of PNA. In conclusion, findings of the present study support the existence of a restricted region of VRG-Apa. VRG-Apa on both sides are closely connected, and integrity of both VRG-Apa is essential for normal respiration.

The origin of medullary cells that form the cardiac vagal branch and the vagal branches in the lower thorax innervating the gastrointestinal (GI) tract was studied using horseradish peroxidase (HRP), a retrograde transport tracer in the cat. The distributions of parasympathetic postganglionic neurons of the heart were studied with acetylcholinesterase histochemistry. Intracardiac ganglionic neurons were found mainly in the connective tissue surrounding the base of the pulmonary arteries and in an area in and dorsal to the interatrial septum. Following injection of HRP into the subepicardum where most of the cardiac postganglionic neurons reside, 91% of the labelled neurons were found bilaterally distributed in the nucleus ambiguus (NA). A small population of labelled neurons was found in the dorsal motor nucleus of the vagus (DMV) and an intermediate zone (IZ) between the two nuclei. When HRP was injected into the left or right cardiopulmonary vagus branch, labelled neurons were found exclusively in the ipsilateral NA, DMV and IZ with a predominance in the NA. In the thorax, after they course around the heart, the left and right thoracic vagus nerves divides into a left and a right branch, respectively. The left branch of the left thoracic vagus joins the left branch of the right thoracic vagus to form the anterior vagus nerve at 3 cm above the diaphragm. The right branch of the right thoracic vagus nerve joins the right branch of the left thoracic vagus to form the posterior vagus nerve. After application of HRP into the right or the left branch of the left thoracic vagus, HRP labelled cells were found in the left DMV. Similarly, after application of HRP into the left or the right branch of the right thoracic vagus, labelled cells were found in the right DMV. On the other hand, when HRP was injected into the anterior vagus, labelled neurons were found bilaterally in the DMV. This suggests that all rostral branches of the thoracic vagus have their origin in the ipsilateral DMV, and intermixing occurs only at the caudal level near the diaphragm. Findings of the present experiments suggest that parasympathetic preganglionic neurons innervating the GI tract are located exclusively in the DMV while those of the heart are located mainly in the NA. Within the DMV, GI vagal neurons were found medially from the level 0-2.5 mm rostral to the obex. In contrast, cardiac vagal neurons were found in the lateral edge of the DMV at the level 0-1 mm rostral to the obex.

The functional correlation of the depressor caudal ventrolateral medulla (CVLM) with the two pressor regions, i.e. rostral ventrolateral medulla (RVLM) and dorsomedial medulla (DM), and with another inhibitory region, i.e. the paramedian reticular nucleus (PRN), were studied in cats anesthetized intraperitoneally with chloralose (40 mg/kg) and urethane (400 mg/kg). Systemic arterial pressure (SAP), heart rate (HR) and the sympathetic vertebral nerve activity (VNA) were recorded. The correct location of CVLM, RVLM or DM was determined by their specific responses, i.e. decreases of SAP, HR and VNA, for CVLM increases of these parameters for RVLM and DM, elicited first by electrical stimulation (80 Hz, 0.5 ms, 50-100 microA) then followed by microinjection of glutamate (Glu, 0.25 M, 70 nl). The depressor action of PRN was produced by electrical stimulation only. It was found that the depressor responses caused by the CVLM stimulation were greatly reduced 2 h after lesioning either the RVLM or DM by microinjection of kainic acid (KA, 24 mM, 200 nl) ipsilateral to the side of CVLM stimulation. The CVLM responses were further reduced after the remaining side of RVLM or DM was lesioned. The reduction of the CVLM-depressor responses was more apparent after the RVLM than DM lesioning. Data suggest that the CVLM-depressor responses are mediated through inhibition of the sympathetic-pressor neurons in both RVLM and DM with predominance of the former. Lesioning the PRN by KA and/or combination with DC electrolytic lesion reduced the CVLM-induced depressor responses. In turn, lesioning the CVLM by KA reduced the PRN-induced depressor responses. The reduction in the later manipulation was more apparent in the PRN-depressor responses than the CVLM-depressor responses. Data suggest that part of the PRN depressor action is mediated through activation of the CVLM.

Oxidized copper leadframe was cleaned using Ar/H 2 plasma in a conventional RF-plasma cleaner. It was found that the etching (cleaning) rate of oxide increased with the decrease of Ar/H 2 ratio, and reached maximum at Ar/H 2 = 0.25, under which the cleaning rate was 12.6 nm/min. The result showed that chemical effect was more significant than the physical sputtering effect. However, the cleaning rate then decreased a little when 100% of hydrogen was used. This could be due to the decrease of plasma density. In order to increase further the etching rate, oxidized samples were placed inside a rectangular hollow cathode. The results showed that the smaller the height of the hollow cathode was, the faster the etching rate would be. This is due to the increase of plasma density. In addition, it is also found that surface micro-roughness decreased with the increase of H 2 concentration.

TiO2 (rutile and anatase) thin films was first prepared using reactive sputtering, in an Ar+O2 plasma. In the 2nd stage of the experiment, various amounts (3, 7, and 10 at. %) of Ag was doped into the rutile film in order to form TiO2-Ag thin films. These films were annealed for one hour in Ar atmosphere, at 300, 400, and 500 °C. The films' structures were then examined using X-ray diffractometry. FESEM (field-emission scaning electron microscopy) was used to investigate the surface emergence of Ag particles. As for the examination of optical band gaps and absorption of these films, UV-Vis-NIR photometer was used. The results show that, in as-deposited condition, the addition of Ag might disrupt the growth of crystalline structure and cause the formation of amorphous films. After annealing, it is found that the structure tends to become anatase phase which is a metastable phase between amorphous titanium oxide and rutile. More importantly, the absorption of the Ag-doped films would be enhanced in the visible-light range. Some of the enhancement is clearly due to plasmon resonance effect. The Ag-doped samples have shown some antibacterial effect in dark. When irradiated with light, the samples show a synergistic behavior combining the bactericidal effect of Ag ions and photocatalytic effect of TiO2.

Time and temperature relationships of both a menu item and the convection oven at three oven-load sizes and three oven temperatures in a convection oven were investigated. Energy use for both the empty oven and turkey rolls at different operating conditions was monitored. The estimation of energy use of turkey rolls was studied based on time and temperature relationships of both the convection oven and food product. Results showed that energy use at a designated oven temperature can be estimated by using the following information: energy use per pound of the raw product, amount of the raw product, energy rating for the convection oven to warm up and maintain the oven temperature, the time to warm up the oven and the length of heating time. The largest oven load size (six rolls) had the highest energy efficiency. Administrative dietitians and foodservice managers may apply this method to their operation and organize the relevant information on energy use in their computers to assist with production planning and operational decision making.