386 research outputs found
Generation of pseudo-radially-polarized beams in a diode pumped solid-state laser
A simple technique for directly generating pseudo-radially-polarised or donut-shaped beams in a diode-pumped solid-state laser is presented. Preliminary results for a Nd:YAG laser are described and the further potential of this technique is discussed
High power radially-polarized Yb-doped fiber laser
A simple technique for directly generating a radially-polarized output beam from an ytterbium-doped fiber laser using an intracavity spatially-variant waveplate is reported. The laser yielded 32W of output with a corresponding slope efficiency of 65.8% in a radially-polarised beam with beam propagation factor ~2.1 and polarization purity >95%
Novel technique for the CO<sub>2</sub> laser fabrication of optical devices with sub-micrometer ablation depth precision
We present novel techniques for the processing of fibre end face and cladding surfaces using a 9.6 µm CO2 laser. We investigate the effects of pulse duration on process parameters
Behavioral and morphological traits interact to promote the evolution of alternative reproductive tactics in a lizard
Alternative reproductive tactics (ARTs) are predicted to be the result of disruptive correlational selection on suites of morphological, physiological, and behavioral traits. ARTs are most obvious when they occur in discrete morphs with concomitant behav
Direct generation of radially-polarized output from an Yb-doped fiber laser
A simple technique for directly generating a radially-polarized output beam from an ytterbium-doped fiber laser using an intracavity S-waveplate is reported. The laser yielded 7W of output with a corresponding slope efficiency of 67%
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Long-length contaminated equipment burial containers fabrication process procedures
These special process procedures cover the detailed step-by-step procedures required by the supplier who will manufacture the Long-Length Contaminated Equipment (LLCE) Burial Container design. Also included are detailed step-by-step procedures required by the disposal process for completion of the LLCE Burial Containers at Hanford
A comparative study on wear and corrosion behaviour of tungsten carbide-nickel and tungsten carbide-cobalt high velocity oxy-fuel (HVOF) for carbon steel blade
Nowadays, the demand of high wear and corrosion resistance of the components in
various industry is increasing from time to time. Therefore, high velocity oxy-fuel
(HVOF) thermal spray was introduced to protect machine components from wear and
corrosion, to restore worn components and to improve the durability of the
components. HVOF is one of the process of depositing a material layer over a base
metal or substrate with characteristics of high flame velocity and moderate
temperature. The main purpose of this present study is to characterize the structure of
the tungsten carbide 10 wt.% nickel (WC-10Ni) and tungsten carbide 12 wt.% w cobalt
(WC-12Co) coating deposited by means of HVOF thermal spray onto a continuous
digester (CD) blade that made up from carbon steel. The morphology and chemical
composition of the coating were characterized by scanning electron microscope
(SEM), electron dispersive spectrometer (EDS), and x-ray diffraction (XRD). The
hardness test was carried out by using Vickers micro-hardness tester with load of 490.3
mN (0.05 HV). The wear and corrosion behavior and mechanism for both coatings
was compared. Three body wear test was carried out in term of weight loss and
electrochemical test was performed in acidic media (mixture of sulfuric acid, H2SO4
and ilmenite) to obtain the corrosion rate of the coating. From the result, it shows that
WC-12Co coating has finer grain size that is around 2.3 ÎĽm. WC-12Co has higher
wear resistance due to high volume friction, low mean free path, high hardness and
lower porosity distribution compared to WC-10Ni. Besides, the formation of
secondary phase, W2C also affected the hardness of both coating, where this phase is
harder than WC phase. For corrosion test, WC-12Co shows good corrosion resistance
with small differences of corrison rate with WC-10Ni, that is only 0.7016 mm/y. As a
conclusion, WC-12Co HVOF coating shows high potential on replacement of CD
blade
Effect of Cooking and Roasting on Nutritional and Anti-Nutritional Factors in Kenaf (Hibiscus Cannabinus L.) Seed Meal.
The effect of cooking and roasting on levels of nutrients and anti-nutritional factors in Kenaf (Hibiscus cannabinus) seed meal was investigated. Significant (p < 0.05) variation existed in the nutrient levels among the raw, cooked and roasted kenaf seed meal. Roasting resulted in a significant (p < 0.05) increase in crude protein and mineral composition. The processing methods had no significant (p > 0.05) effect on the phytic acid but significantly (p < 0.05) reduced the tannin content of the kenaf seed meal. While cooking significantly (p < 0.05) reduced the trypsin inhibitors, roasting did not significantly (p > 0.05) alter the trypsin inhibitory activities in Kenaf seed meal when compared with the unprocessed kenaf seed meal. Key words: Hibiscus cannabinus; Kenaf seed meal; Cooking; Roasting; Nutrient; Anti-nutritional factor
Precocial juvenile lizards show adult level learning and behavioural flexibility
This project was funded by an ARC Discovery grant (DP130102998) to M.J.W. and R.W.B. and by Macquarie University.In altricial species, young rely on parental care and brain maturation mainly occurs after birth. In precocial species, young are born at a more advanced developmental stage in need of less or no parental care and brain development is mostly completed at the time of birth. We therefore predicted early maturation of learning ability in precocial species. We used a series of visual discrimination and reversal stages to investigate the ability of the precocial eastern blue-tongue lizard, Tiliqua scincoides scincoides, a long-lived Australian lizard species with slow-developing young, to respond to changes in stimulus relevance and test for behavioural flexibility. To test whether age affects learning in this species, we compared juveniles (23–56 days) with adults (sexually mature, at least 2 years). In accordance with our expectations, adults and juveniles performed similarly well in all stages, suggesting that juveniles of this precocial species learn at adult levels from an early age. Both age classes performed well during reversals showing good behavioural flexibility. This is the first study in lizards to directly compare juvenile and adult behavioural flexibility. Importantly, we demonstrate that precocial lizards can begin life with an advanced cognitive ability already in place.In altricial species, young rely on parental care and brain maturation mainly occurs after birth. In precocial species, young are born at a more advanced developmental stage in need of less or no parental care and brain development is mostly completed at the time of birth. We therefore predicted early maturation of learning ability in precocial species. We used a series of visual discrimination and reversal stages to investigate the ability of the precocial eastern blue-tongue lizard, Tiliqua scincoides scincoides, a long-lived Australian lizard species with slow-developing young, to respond to changes in stimulus relevance and test for behavioural flexibility. To test whether age affects learning in this species, we compared juveniles (23–56 days) with adults (sexually mature, at least 2 years). In accordance with our expectations, adults and juveniles performed similarly well in all stages, suggesting that juveniles of this precocial species learn at adult levels from an early age. Both age classes performed well during reversals showing good behavioural flexibility. This is the first study in lizards to directly compare juvenile and adult behavioural flexibility. Importantly, we demonstrate that precocial lizards can begin life with an advanced cognitive ability already in place.In altricial species, young rely on parental care and brain maturation mainly occurs after birth. In precocial species, young are born at a more advanced developmental stage in need of less or no parental care and brain development is mostly completed at the time of birth. We therefore predicted early maturation of learning ability in precocial species. We used a series of visual discrimination and reversal stages to investigate the ability of the precocial eastern blue-tongue lizard, Tiliqua scincoides scincoides, a long-lived Australian lizard species with slow-developing young, to respond to changes in stimulus relevance and test for behavioural flexibility. To test whether age affects learning in this species, we compared juveniles (23–56 days) with adults (sexually mature, at least 2 years). In accordance with our expectations, adults and juveniles performed similarly well in all stages, suggesting that juveniles of this precocial species learn at adult levels from an early age. Both age classes performed well during reversals showing good behavioural flexibility. This is the first study in lizards to directly compare juvenile and adult behavioural flexibility. Importantly, we demonstrate that precocial lizards can begin life with an advanced cognitive ability already in place.In altricial species, young rely on parental care and brain maturation mainly occurs after birth. In precocial species, young are born at a more advanced developmental stage in need of less or no parental care and brain development is mostly completed at the time of birth. We therefore predicted early maturation of learning ability in precocial species. We used a series of visual discrimination and reversal stages to investigate the ability of the precocial eastern blue-tongue lizard, Tiliqua scincoides scincoides, a long-lived Australian lizard species with slow-developing young, to respond to changes in stimulus relevance and test for behavioural flexibility. To test whether age affects learning in this species, we compared juveniles (23–56 days) with adults (sexually mature, at least 2 years). In accordance with our expectations, adults and juveniles performed similarly well in all stages, suggesting that juveniles of this precocial species learn at adult levels from an early age. Both age classes performed well during reversals showing good behavioural flexibility. This is the first study in lizards to directly compare juvenile and adult behavioural flexibility. Importantly, we demonstrate that precocial lizards can begin life with an advanced cognitive ability already in place.PostprintPeer reviewe
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Effect of water-soluble polymers, polyethylene glycol and poly(vinylpyrrolidone),on the gelation of aqueous micellar solutions of Pluronic copolymer F127
The micellization of F127 (E98P67E98) in dilute aqueous solutions of polyethylene glycol (PEG6000 and
PEG35000) and poly(vinylpyrrolidone) (PVP K30 and PVP K90) is studied. The average hydrodynamic
radius (rh,app) obtained from the dynamic light scattering technique increased with increase in PEG concentration
but decreased on addition of PVP, results which are consistent with interaction of the micelles
with PEG and the formation of micelles clusters, but no such interaction occurs with PVP. Tube inversion
was used to determine the onset of gelation. The critical concentration of F127 for gelation increased on
addition of PEG and of PVP K30 but decreased on addition of PVP K90. Small-angle X-ray scattering
(SAXS) was used to show that the 30 wt% F127 gel structure (fcc) was independent of polymer type
and concentration, as was the d-spacing and so the micelle hard-sphere radius. The maximum elastic
modulus (G0
max) of 30 wt% F127 decreased from its value for water alone as PEG was added, but was little
changed by adding PVP. These results are consistent with the packed-micelles in the 30 wt% F127 gel
being effectively isolated from the polymer solution on the microscale while, especially for the PEG, being
mixed on the macroscale
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