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Two experimental groups were applied to measure oxygen consumption (OC) of young grey mullets Mugil cephalus (TL: 27.3±2.1 cm; TW: 187.9±45.8 g) at different temperatures (15, 20, and 25°C). Specimens of fish from seawater (30 psu) and freshwater (0 psu) were transferred in to brackish water (15 psu). Rate of fish OC after rearing in brackish water, showed significant difference (P2/kg/h at temperatures of 15, 20, and 25°C, respectively. In fish from freshwater transferred to brackish water, grey mullets consumed 80.5, 114.4, and 161.5 mg O2/kg/h at 15, 20, and 25°C, respectively (PP>0.05). It can be concluded, that the OC rate of grey mullets on brackish water has the tendency to increase by temperature rise.

A new method for fabricating large-area well-aligned ZnO pillars, solely using radio-frequency magnetron sputtering, is reported. A mixture of argon and hydrogen gases was used as the plasma source, acting as a reduction agent. The ZnO pillars grow from a ZnO buffer layer with a ZnMgO nucleation stabilization layer on top, with the sputtered targets sharing the same composition. The entire growth is well controlled and linear. A shadowing effect is also responsible for the growth. The characteristics of the developed method are high uniformity and reproducibility, as commonly known for sputtering, which are vital prerequisites for future developments of nanodevices.

The recent advance in soft solution processing of inorganic materials offers an exciting opportunity to develop large-area manufacturing technologies for inorganic thin-film transistors (TFTs). In this paper, we report our recent progress in fabricating CdS TFTs using chemical bath deposition (CBD) to deposit CdS channel layers. Device analysis of an enhancement-mode CdS metal-insulator-semiconductor field effect transistor (MISFET) with a field-effect mobility of ∼1.5 cm 2 V -1 s -1 and a threshold voltage of v T ∼ 14 V is reported here. An on-to-off ratio of ∼10 6 is achieved. This rather large drain current on-to-off ratio indicates that this device will function well as a switch. An examination of the CdS film morphology by scanning electron microscopy indicates that the films deposited by CBD and used for our current device fabrication are dominated by a particle sticking growth mechanism. This is supported by a real-time quartz crystal microbalance growth curve and atomic force microscopy characterizations of the particles formed in the CBD solution. A different bath condition for CBD was tested to obtain a dense CdS layer. A selected-area electron diffraction pattern indicates that the CdS thin film deposited by CBD has a hexagonal structure with an optical bandgap of 2.4 eV as determined by UV-Vis absorption.

The percentages of sperm motility and normal acrosome on the liquid boar semen diluted and preserved at 4°C with lactose hydrate, egg yolk and N-acetyl-D-glucosamine (LEN) diluent were significant differences according to preservation day and incubation time, respectively. The sperm motility steadily declined from 96.9% at 0.5 h incubation to 78.8% at 6 h incubation at 1 day of preservation. However, the sperm motility rapidly declined after 4 day of preservation during incubation. The normal acrosome steadily declined from 93.3% at 0.5 h incubation to 73.8% at 6 h incubation at 1 day of preservation. However, the normal acrosome rapidly declined after 3 day of preservation during incubation. The rates of sperm penetration and polyspermy were higher in 5 and 10×10 6 sperm/ml than in 0.2 and 1×10 6 sperm/ml. Mean numbers of sperm in penetrated oocyte were highest in 10×10 6 sperm/ml compared with other sperm concentrations. The rates of blastocysts from the cleaved oocytes (2-4 cell stage) were highest in 1×10 6 sperm/ml compared with other sperm concentrations. In conclusion, we found out that liquid boar sperm stored at 4°C could be used for in vitro fertilization of pig oocytes matured in vitro. Also, we recommend 1×10 6 sperm/ml concentration for in vitro fertilization of pig oocytes. (Asian-Aust. J. Anim. Sci. 2004. Vol 17, No. 10 : 1369-1373)

Atomic force microscopy (AFM) has been used to determine microstructural changes, etching rates of peritubular dentin, and intertubular dentin recession during demineralization in dilute acidic solutions. These studies have not included many forms of altered dentin, including noncarious sclerotic root dentin associated with Cl V (abfraction) lesions. We sought to determine microstructural changes and recession rates during demineralization in citric acid (pH 2.5, 0.018M) for the transparent/sclerotic zone. Highly polished dentin disks were prepared from teeth with noncarious C1 V lesions (n = 3) and compared with normal root dentin (n = 3). Samples were etched at 5-s intervals for 1 min and at longer intervals up to 30 min. The depth changes in various portions of the dentin with respect to the reference layer were measured and changes in microstructure observed in solution in the wet cell of the AFM. In sclerotic dentin, most tubule lumens were occluded with crystalline deposits that etched more slowly than the other dentin components, but etching rates could not be determined due to their irregular geometry. The intertubular dentin recession quickly reached a plateau after a depth change of

A novel continuous culture system of Acetobacterium sp. coupled with a fixed-bed reactor of Methanosaeta conciliiis described. With methanol (250 mmol l ) plus CO at D= 0.02 h , the productivities of vitamin B 12 and cells were 1.2 mg l .d and 0.31 g l d , respectively, with 83% methanol consumption. With methanol (250 mmol l )-formate (150 mmol l ), however, these productivities increased ca. 2.7-fold, respectively at the same D, with complete consumption of methanol. At D= 0.15 h -1 with these latter substrates, these productivities enhanced ca. 14-fold, that is, 17 mg l .d and 4.3 g l .d, respectively, with 51% methanol consumption.

In this paper, we first demonstrate nanoscale mechanical relays fabricated by a nanoimprint technology, called Contact-Transfer and Mask-Embedded Lithography (CMEL). With this technology, the nanoscale metallic source electrode can be easily fabricated in one step at a low cost. We successfully fabricated the three-terminal nanorelays with various lengths. The nanorelays are demonstrated by measuring the I-V curve of each device. The measured pull-in voltages are compared with the simulation results.

A cDNA for the human "peripheral-type" benzodiazepine receptor (PBR) was isolated from a liver cDNA library. The 851-nucleotide probe hybridized with a approximately 1 kb mRNA in Northern blots of RNA extracted from various human tissues and cell lines. The human PBR probe was hybridized to DNA from a somatic cell hybrid mapping panel to determine that the gene maps to chromosome 22. With a regional mapping panel for chromosome 22, we localized the gene within band 22q13.31. The ligand-binding properties of the receptor expressed from the cDNA were examined in transient expression experiments and compared to the endogenous human PBR. The PBR ligand [3H]PK 11195 had high affinity for the expressed receptor in COS-1 cells, but the affinities of a pair of isoquinoline propanamide enantiomers differed remarkably in expressed and endogenous human PBR. These findings reveal that the host cell and/or post-translational modification may have an important influence on PBR function.

Objectives: This study determined recession rates of peritubular dentin and intertubular dentin in citric acid solution (0.018 M, pH=2.5) for caries-affected transparent dentin, one of the major components of dentin substrate as altered by caries, with comparisons made with non-carious dentin. Methods: Transparent dentin was identified by sagittally sectioning five obviously carious teeth. Sections were then cut through the transparent dentin area perpendicular to the course of the dentinal tubules. Polished dentin samples of the transparent dentin and non-carious dentin were prepared with an internal reference layer and studied at specific intervals for citric acid etching in an atomic force microscope (AFM). Results: At baseline, transparent dentin was identified by dentinal tubules that were largely occluded with mineral deposits that on etching proved to be acid resistant. Peritubular dentin etched rapidly and linearly over time until it could no longer be measured, yielding etching rates for transparent dentin that could not be distinguished from normal dentin. The normal and transparent intertubular dentin surfaces began etching at nearly the same rate, but then surface recession stabilized after less than 1 μm depth change for both dentin types. Significance: Most previous studies have focused on demineralization and bonding to normal dentin, although many bonding procedures involve altered dentin substrates, such as those modified by caries. In this study, peritubular and intertubular dentin from normal and caries-affected dentin exhibited similar behavior. The major difference was the presence of acid resistant mineral in most of tubule lumens in the transparent dentin.

Photodissociation of iodine in CCl4 at 532 nm deposits 6300 cm−1 of energy into the solvent cage immediately surrounding the solute. Picosecond Raman spectroscopy has been used to investigate the dissipation of this energy in the solvent coordinate by monitoring time‐dependent shifts in the Raman lineshapes of the local solvent cage.

In the earlier of 1990's, we have proposed a new process for the synthesis oflight olefins from syngas, which was designated as SDTO method. That is to convert syngas to dimethylether and than to convert dimethylether to light olefins. The present work deals with the R&D research progress of this process. The catalysts were developed for the two reactions, scale-up preparation of the catalysts and pilot plant test were performed. Evaluation of the pilot plant data showed that 190-200 grams of DME were yielded by single-pass for each standard cubic meter of syngas. For the second reaction, material-balance data indicated that 1.880 tons of DME or 2.615 tons of methanol can produce one ton of light olefins, which constituting 0.533 ton of ethylene, 0.349 ton of propylene and 0.118 ton of butenes.

The ultrafast photophysical and photochemical processes following the photodissociation reaction of chlorine dioxide in liquid solutions are investigated using femtosecond transient absorption spectroscopy.

In this work, we developed a continuous flow microreactor that is capable of overcoming the drawbacks associated with chemical bath deposition. Uniform, smooth, and highly oriented nanocrystalline CdS semiconductor thin films were successfully deposited on oxidized silicon substrates at low temperature (80°C) using this microreactor. Functional thin-film transistors with an effective mobility of 1.46 cm 2 /V s were fabricated from the as-deposited films without any postannealing process. This process is a potentially low-cost avenue for the fabrication of thin-film electronics on flexible polymeric substrates.

The interfacial states of the HfO2 thin film grown on the Si(100) substrate by the pulsed laser deposition method is investigated in situ using x-ray photoelectron spectroscopy. They are found to depend on the HfO2 film thickness, oxygen pressure during the pulsed laser deposition growth, and the deposition process. The hafnium silicide is formed in an oxygen-deficient condition, and it can be most effectively controlled by the ambient oxygen pressure during film growth. The close relation between the silicide formation and abundance of the silicon suboxides at the interface is presented.

Low-temperature polycrystalline silicon (poly-Si) is of increasing interest for the display on glass. Among several techniques for the low-temperature poly-Si the Ni-mediated crystallization of amorphous silicon (a-Si) is promising one. We studied the crystalline orientation of the disk-shaped grains in the poly-Si formed by Ni-mediated crystallization of a-Si using a SiO2 nanocap by electron backscattered diffraction measurements. A SiO2 nanocap layer was formed by O2 plasma treatment on a-Si and an ultrathin Ni layer was deposited on the nanocap. It was heated in a UV scan system for crystallization. The Ni atoms in a-Si diffused through the nanocap and formed NiSi2 crystallites. Disk-shaped grains were then grown from these nuclei. The size of disk-shaped grains in poly-Si increases from ∼6 to ∼20 μm when the thickness of nanocap on a-Si changes from 2.4 to 3.2 nm. On the other hand, without the nanocap layer, its size is ∼3.5 μm. The crystalline quality of poly-Si is improved by introducing a nanocap ...

Ni-mediated crystallization of amorphous silicon (a-Si) with a SiO 2 nanocap layer formed by O 2 plasma treatment was studied. An ultrathin Ni layer was deposited on the nanocap and then this was annealed in a UV heating system. The Ni atoms in a-Si films, diffused through the nanocap, formed NiSi 2 crystallites acting as nuclei. Then, disk-shaped grains were grown from the nuclei. The grain size increased from ∼4 to ∼28 μm as the SiO 2 thickness changed from 2.4 to 3.2 nm. The use of a nanocap gave an increased grain size and improved material property.

In this work, chemical bath deposition (CBD) of CdS was monitored using a quartz crystal microbalance as a function of time, temperature, reactant concentration (ex situ atomic absorption measurement), and pH level. It is found that the reaction could be limited by mass transport at certain concentrations and temperatures. The measurements also indicate the total Cd concentration in the solution changes dramatically in the linear growth regime with a constant deposition rate. One possible explanation is that the linear growth regime is actually a combination of molecule-by-molecule growth and cluster-by-cluster growth mode. This hypothesis is further supported by real time dynamic light scattering and transmission electron microscopy measurements.

The photodissociation and geminate recombination of iodine in cyclohexane has been studied by directly monitoring the vibrational coordinates using transient Raman spectroscopy. Energy relaxation as a function of vibrational energy gap has been measured for vibrational spacings of 210 to 130 cm−1. These vibrational levels correspond approximately to v=3 to v=52 with energies 740 to 9300 cm−1 above the zero point level. The results support earlier experiments in that over 100 ps is required to completely relax the vibrational energy.

As is well known, ambient atmospheres can greatly affect the friction and wear behavior of metals sliding on each other, as well as the electric contact resistance between the metals. In order to better understand the mechanisms of those effects of ambient atmospheres, the coefficient of friction and the electric contact resistance have been studied for bundles of 50 micrometer thick copper wires, sliding on a polished copper surface in a specialized apparatus, called the hoop apparatus. The ambient gas was cycled between laboratory air and carbon dioxide, and between laboratory air and argon, respectively. The results indicate a reversible build-up and removal of surface films whose nature as well as speed of formation and removal depends on the gas present. Fiber bundles are used in order to eliminate the constriction resistance, so that the contact resistance is directly proportional to the specific film resistivity. The following properties were found to be affected by the ambient gases. (i) The average level of the contact resistance. (ii) The amplitude of the electric “noise.” (iii) The coefficient of friction. (iv) The difference between the static and the dynamic coefficients of friction in stick-slip motion. The results were found to be consistent with previous measurements in which the mechanism of forming wear particles was deduced from a wear chip analysis. Correspondingly they were interpreted in terms of the same wear model. This led to a further advance in the understanding of the interfacial processes accompanying sliding in this sample/substrate combination.

Utilisation de la spectrometrie Raman pour l'etude du transfert d'electron entre des coordinats dans les etats de transfert de charge des complexes de metaux de transition D 3 . Dans tous les complexes etudies, les effets dynamiques de solvant sur le processus de transfert d'electron sont minimes

Two color picosecond Raman spectroscopy has been utilized to measure interligand electron transfer in the excited MLCT states of mixed ligand Ru(II) complexes. No contribution to electron transfer was found from hot vibrational levels produced by photoexcitation. For thermally relaxed vibrational levels the first direct measurement of the upper limit to the rate of interligand electron hopping is reported. It was found that the rate from the thermally equilibrated vibrational states was ≤2×106 s−1. Low temperature Raman spectra indicate that the slow rate of electron transfer creates a nonstatistical energy distribution between dissimilar ligands. The implications of these results are discussed within the framework of electron transfer theory.

A series of poly(vinyl formal) membranes was synthesized by formalization of poly(vinyl alcohol) membranes. Representative pieces were selected for this study. Some cellulose acetate membranes cast from dioxane were used for comparison. The main experimental techniques employed included water absorption measurements and direct osmosis measurements. Aqueous solutions of sodium chloride at various concentrations were used for the studies of permeation through the membranes by direct osmosis. The plot of water permeability coefficient Pw versus volume fraction Vw of water absorbed in a membrane was interpreted in terms of the effect of two different types of absorbed water molecules. The individual diffusion coefficients were evaluated from asymptotic slopes of the curves. Similar analyses applied satisfactorily to data found in the literature.

The permeation properties of formalized poly(vinyl alcohol) membranes are described. The interest of this work is centered on the properties relevant to desalination by reverse osmosis. These membranes, when properly prepared, showed reasonably high water permeability, high salt rejection, and stability in the presence of acids and alkalies.

A system of synthesis of polyether-based urethanes was developed which had sufficient flexibility in composition so that transport properties could be optimized. Mixtures of poly(oxyethylene) glycol (PEG) and poly(oxypropylene) glycol (PPG) of a variety of molecular weights were tied together by varying amounts of kinds of “hard segments.” Thus, the water swell, the mechanical properties, and the size of the soft blocks and hard blocks could be varied. With a fixed content of hard segments, the water absorption decreased with decrease in the PEG/PPG ratio, demonstrating the feasibility of producing controlled changes in hydrophilicity of the polymer without significant change in the mechanical strength. Some polyurethanes based on PEG 600 and PPG 425 had a very good high value of Pw/Ps but a somewhat low value of Pw. The polyurethanes prepared by using phenylenediamines as chain extenders had markedly enhanced modulus and an extended rubbery plateau region, as anticipated.

Regenerative amplification of temporally compressed picosecond pulses is demonstrated in neodymium: yttrium aluminum garnet (Nd:YAG) at 2 kHz. The seed to the regenerative amplifier originates from a chirped cw mode‐locked Nd:YAG laser pulse. The initial 100 nJ ∼80 ps full width at half‐maximum pulses are amplified and temporally compressed to ∼200 μJ/pulse at a repetition rate of 2 kHz with a pulse width of 12 ps.

Direct measurements of dynamic charge localization in tris (2,2′‐bipyridyl) ruthenium (II) have been performed in fluid solution for the first time. Using picosecond Raman spectroscopy it has been determined that charge localization occurs on a time scale of ≪30 ps for low‐viscosity solvents. In high‐viscosity solvents such as glycerol at room temperature, the charge localized species Ru(bpy)2(bpy)− appears on a time scale of 100 ps. It is clear from these data that solvent reorganization is one of the dominant mechanisms in electron trapping.