bluuebunny/crossref_metadata_2025 huggingface dataset:
Transient thermal analysis of InGaAsP-InP high-power diode laser arrays with different fill factors
Authors: Gourevitch A. , Laikhtman B. , Westerfeld D. , Donetsky D. , Belenky G. , Trussell C. W. , Shellenbarger Z. , An H. , Martinelli R. U.
Published: March 2005

The temperature kinetics of InGaAsP∕InP high-power laser diode arrays with different fill factors was studied experimentally and theoretically. It was shown that except during a short initial period, the laser array heating is determined by the heat flux propagation through the heat spreader. To characterize this heating, we developed a two-dimensional analytical model. Experimentally, the temperature change in the active region was obtained by measuring the laser spectrum’s temporal evolution during a single current pulse. Three distinctive periods in the transient heating process were clearly identified—an initial temperature rise, a square-root-of-time dependence of the active-region temperature increase, and an exponential approach of the active-region temperature to its steady-state value. We demonstrated that in the initial period of time, the heat propagates within the laser bar structure, and the laser bar design (fill factor) strongly affects the active-region temperature rise. In the later periods the temperature kinetics is insensitive to the fill factor.
A model for heterogeneous materials including phase transformations
Authors: Addessio F. L. , Clements B. E. , Williams T. O.
Published: March 2005

A model is developed for particulate composites, which includes phase transformations in one or all of the constituents. The model is an extension of the method of cells formalism. Representative simulations for a single-phase, brittle particulate (SiC) embedded in a ductile material (Ti), which undergoes a solid–solid phase transformation, are provided. Also, simulations for a tungsten heavy alloy (WHA) are included. In the WHA analyses a particulate composite, composed of tungsten particles embedded in a tungsten–iron–nickel alloy matrix, is modeled. A solid–liquid phase transformation of the matrix material is included in the WHA numerical calculations. The example problems also demonstrate two approaches for generating free energies for the material constituents. Simulations for volumetric compression, uniaxial strain, biaxial strain, and pure shear are used to demonstrate the versatility of the model.
The unified cycle model of a class of solar-driven heat engines and their optimum performance characteristics
Authors: Zhang Yue , Lin Bihong , Chen Jincan
Published: March 2005

The unified cycle model of a class of solar-driven heat engines is presented, in which the heat loss of the solar collector and the external and internal irreversibilities of the heat engine are taken into account and used to investigate the optimal performance of the cyclic system. The maximum overall efficiency of the system is calculated. The optimally operating temperature of the solar collector, the optimal temperatures of the cyclic working substance, and the optimal ratio of the heat-transfer areas of the heat engine are determined. The influence of the heat loss of the solar collector and the external and internal irreversibilities of the heat engine on the cyclic performance is discussed in detail. Some important characteristic curves are given. It is more important that the results obtained from the unified cycle model are very general and useful, from which the optimal performance of the solar-driven Brayton, Braysson, and Carnot heat engines and some solar-driven heat engines can be directly derived.
Patterning organic luminescent materials by solvent-assisted dewetting and polymer-bonding lithography
Authors: Luan Shifang , Cheng Ziyong , Xing Rubo , Wang Zhe , Yu Xinhong , Han Yanchun
Published: March 2005

A combined approach of solvent-assisted dewetting and polymer-bonding lithography was employed to pattern the luminescent materials on the polymer-coated substrate. In saturated solvent vapor atmosphere, light-emitting material films (e.g., Alq3∕PVK,PhE-PdI4∕PS) on the polydimethylsiloxane mold could dewet and form isolated micropatterns directed by the mold. Then, the microstructures were transferred to the polymer-coated substrates based on the surface adhesion to generate the useful isolated and well-defined light-emitting patterns. The optical property of Alq3∕PVK remains almost unaffected in the patterning process. The combined approach is applicable to other organic functional materials and polymer-coated surfaces with different physical and chemical properties and has potential applications in organic microelectronics fabrication.
Decay of photorefractive gratings in LiNbO3:Fe by neutron irradiation
Authors: Mandula G. , Rupp R. A. , Balaskó M. , Kovács L.
Published: March 2005

The effect of neutron irradiation on photorefractive gratings in LiNbO3:Fe single crystals is studied experimentally. The observed phenomena result from the large effective cross section of Li6 for thermal and cold neutrons and from the large number of the electrons excited to the conduction band by the high kinetic energy that is released during the neutron generated fission of Li6 nuclei. The excited electrons erase the previously recorded holographic grating. The sensitivity threshold of the effect is better than 160mSv (1.2×1010cm−2 fluence) at neutron energy of 0.17eV. Potential applications of the phenomena are discussed.
Dynamic evolution of nanoscale shear bands in a bulk-metallic glass
Authors: Yang Bing , Morrison Mark L. , Liaw Peter K. , Buchanan Raymond A. , Wang Gongyao , Liu Chain T. , Denda Mitsunori
Published: March 2005

Dynamic shear-band-evolution processes in a bulk-metallic glass (BMG), an emerging class of materials, were captured by a state-of-the-art, high-speed, infrared camera. Many shear bands initiated, propagated, and arrested before the final fracture in tension, each with decreasing temperature, and shear-strain profiles. A free-volume-exhaustion mechanism was proposed to explain the phenomena. The results contribute to understanding and improving the limited ductility of BMGs, which otherwise have superior mechanical properties.
Lithographically defined metal-semiconductor-hybrid nanoscrolls
Authors: Schumacher O. , Mendach S. , Welsch H. , Schramm A. , Heyn Ch. , Hansen W.
Published: March 2005

We report on two-layer metal-semiconductor-hybrid scrolls fabricated from rolled-up strained metal∕InGaAs-layers. As the central approach, the metallic layer itself acts as a stressor in contact with the semiconductor. Position and length of the scrolls can be precisely tuned by patterning the e-beam-evaporated metallic stressor with conventional lithographic techniques. The thickness of the metallization determines the radius of the resulting scrolls. This fabrication technique significantly improves the reliability and simplifies the fabrication of metal∕semiconductor three-dimensional objects which employ bending up layers. Even more important, using this technique the bending radius of such three-dimensional objects can easily be downsized to very small radii in the nanometer scale, e.g. in order to build nano-electro-mechanical systems.
Heteroepitaxial Bi3Fe5O12∕La3Ga5O12 films for magneto-optical photonic crystals
Authors: Khartsev S. I. , Grishin A. M.
Published: March 2005

Epitaxial La3Ga5O12 (LGG) garnet films and Bi3Fe5O12∕La3Ga5O12 (BIG/LGG) heteroepitaxial film structures have been synthesized on the Gd3Ga5O12(GGG,111) single crystal. LGG films were grown by pulsed laser deposition technique whereas rf-magnetron sputtering was used to grow BIG films. LGG has a lattice constant 12.768Å that is bigger than that in GGG (12.384Å) and closer to that in BIG (12.626Å). We demonstrate feasibility of integration lanthanum gallium garnet with a giant Faraday rotator Bi3Fe5O12 in magneto-optical photonic crystals. Heteroepitaxial Bi3Fe5O12(1.9μm)∕La3Ga5O12(300nm)∕GGG(111) structures show Faraday rotation as high as 5.74deg∕μm compared to 5.46deg∕μm in BIG/GGG at λ=655nm. Fitting LGG reflectivity spectra to Fresnel formulas yields LGG refractive index no=1.981 compared to 1.963 in GGG at 655nm. Dispersion of LGG refraction index follows Sellmeier formula no2=1+2.77∕[1−(143nm∕λ)2] in the range from 400nm to 1000nm.
Epitaxial nature and anisotropic dielectric properties of (Pb,Sr)TiO3 thin films on NdGaO3 substrates
Authors: Lin Y. , Chen X. , Liu S. W. , Chen C. L. , Lee Jang-Sik , Li Y. , Jia Q. X. , Bhalla A.
Published: March 2005

Epitaxial behavior of (Pb,Sr)TiO3 thin films on (110) NdGaO3 substrates fabricated in different conditions have been investigated using high resolution x-ray diffraction and characterized with interdigital dielectric measurement. A slow cooling results in films with a-axis normal to the surface (a-axis growth), whereas a fast cooling leads to growth of c-axis oriented films. The dielectric properties of the films prepared under different cooling rates are closely related to the crystalline structure of the films.
Regenerated surface plasmon polaritons
Authors: Lee Tae-Woo , Gray Stephen K.
Published: March 2005

We discuss a way to increase surface plasmon polariton (SPP) propagation lengths and intensities. It involves reflecting radiation loss back to the propagation surface, regenerating SPPs. This is achieved with a metal-dielectric structure, which is also designed to efficiently couple in external light. Flexibility in the design of the structure allows for optimization of SPP properties. Extensive finite-difference time-domain simulations, including coupling external light into the system, demonstrate the approach.
Air flow technique for large scale dispersion and alignment of carbon nanotubes on various substrates
Authors: Hedberg James , Dong Lifeng , Jiao Jun
Published: March 2005

Herein we present a method to disperse and align carbon nanotubes on various substrate surfaces. Using the shear forces associated with a rapidly moving fluid, nanoscale objects were positioned in a direction corresponding to the flow vector of the fluid. Dispersion of carbon nanotubes on microaddressable electrodes via the gas flow method creates opportunities for scaling up the production of nanoscale devices. In this letter, we demonstrate the feasibility of the method and the electrical characterization results obtained after the fabrication of carbon nanotube testing structures.
Polycapillary optics for energy dispersive micro x-ray diffractometry
Authors: Bjeoumikhov A. , Bjeoumikhova S. , Langhoff N. , Wedell R.
Published: March 2005

Energy dispersive microdiffractometry can be carried out using a microfocus x-ray source coupled to a polycapillary lens, which provides an 8000-fold intensity gain. As result this letter shows the orientation of molybdenum microcrystallites over a square area of 4mm2 with a spatial resolution of 50μm.
Anomalous gap dependence of stretched Teflon∕poly(p-phenylene vinylene) films
Authors: Marletta A. , Miwa R. H. , Cazati T. , Guimarães F. E. G. , Faria R. M. , Veríssimo-Alves M.
Published: March 2005

We have performed an experimental study of the anomalous increase of the gap energy (Egap) in stretched Teflon∕poly (p-phenylene vinylene) films. Photoluminescence experiments, show that Egap initially undergoes an increase and then a decrease, as the film is stretched further. Polarized absorbance experiments reveal orientational ordering of chains with the stretching.
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nanowire arrays on sapphire grown by high-pressure pulsed-laser deposition
Authors: Lorenz M. , Kaidashev E. M. , Rahm A. , Nobis Th. , Lenzner J. , Wagner G. , Spemann D. , Hochmuth H. , Grundmann M.
Published: March 2005

Mg x Zn 1 − x O nanowires with Mg-content x from 0 to 0.2 have been grown by high-pressure pulsed-laser deposition (PLD) on gold-covered sapphire single crystals. The PLD process allows for a unique wide-range control of morphology, diameter, and composition of the MgxZn1−xO nanowires. The diameter of single ZnO wires could be varied between about 50 and 3000 nm, and the Mg content x of MgxZn1−xO wire arrays was controlled via the PLD gas pressure. The microscopic homogeneity of Mg content is displayed by cathodoluminescence (CL) imaging of the excitonic peak energy. The fluctuation of CL peak energy between individual wires is about an order of magnitude smaller than the alloy broadening.
Density functional theory study of adsorption and dissociation of HfCl4 and H2O on Ge∕Si(100)-(2×1): Initial stage of atomic layer deposition of HfO2 on SiGe surface
Authors: Chen Wei , Lu Hong-Liang , Zhang David Wei , Xu Min , Ren Jie , Zhang Jian-Yun , Wang Ji-Tao , Wang Li-Kang
Published: March 2005

We have investigated adsorption and dissociation of water and HfCl4 on Ge∕Si(100)-(2×1) surface with density functional theory. The Si–Ge heterodimer and Ge–Ge homodimer are employed to represent the Si1−xGex surface. The activation energy for adsorption of water on Ge–Ge homodimer is much higher than that on Si–Ge heterodimer. No net activation barrier exists during the adsorption of HfCl4 on both SiGe surface dimers. The differences in the potential energy surface between reactions on Si–Ge and Ge–Ge dimers are due to different bond strengths. It should also be noticed that the activation energy for HfCl4 is quite flat, thus HfCl4 adsorbs and dissociates on Ge∕Si(100)-(2×1) easily.
Increased beef production from Townsville lucerne (Stylosanthes sundaica Taub.) in the spear grass pastures of central coastal Queensland
Authors: Shaw NH
Published: March 2005

The performance of Townsville lucerne (Stylosanthes sundaica Taub.) as a legume for inclusion in native pastures dominated by spear grass (Heteropogon contortus (L.) Beauu. ex R. & S.) has been studied near Gladstone, in central coastal Queensland. A pasture mixture of Townsviille lucerne and spear grass, given 10.5 cwt 73 superphosphate, 1.5 cwt potassium chloride, and 5 oz sodium molybdate an acre, over a six-year period: produced five times as much Live-weight gain per acre as untreated native pasture. This increase was a combination of higher carving capacity and greater live-weight gain per head. In addition stock. were marketed at from one to two years earlier than normal. Pot and small replicated field experiments showed that Townsville lucerne responded significantly only to superphosphate and did not require potassium or various trace elements including molybdenum on these soils.
Detection of two legume viruses in Australia.
Authors: Swenson KG , Venables DG
Published: March 2005

Two viruses were isolated from pasture legumes at Canberra, A.C.T. Symptoms on appropriate indicators and serological tests have shown them to be strains of lucerne mosaic virus and white clover mosaic virus. Neither virus has previously been reported in legumes in Australia.
A compact instrument for measuring the total salinity of water on pastoral properties.
Authors: Box GFH , Wilson BW
Published: March 2005

The management of water supplies on pastoral properties in the marginal rainfall areas of Australia is often hampered by the lack of an inexpensive reliable device for measuring the total salinity of ground water. The instrument described has been developed with this specific function in view although with further elaboration it could fulfil the requirements of an accurate laboratory, instrument for measuring conductivity. Basically the electronic components consist of an oscillator, a bridge, a single stage of amplification and a small speaker. When in use the speaker emits a high-pitched whistle until the bridge is balanced at a null point. By using transistors the current drain is low, the weight and cost of the instrument is Low and the equipment is rugged enough to withstand rough treatment. The total salinity of water can be measured accurately in terms of conductivity over the limited range covering the requirements for sheep and cattle and other ranges could be accommodated by minor modifications.
The influence of plant population on the yield of cotton at Katherine, N.T
Authors: Phillips LJ , Norman MJT
Published: March 2005

In 1957-58 and 1958-59, cotton was grown under dryland conditions on Tippera clay loam at Katherine, N.T., at plant populations of 4, 8, 16, 32 and 64 thousand plants per acre, under three nitrogen fertilizer treatments and at two dates of planting. In 1960-61, cotton was grown at 8, 16, 24, 32, 40 and 48 thousand plants per acre at one date of planting and at a standard nitrogen fertilizer level. The 1957-58 and 1958-59 results showed that 8, 16, and 32 thousand plants per acre gave a higher yield of seed cotton than 4 and 64 thousand plants per acre, with no interaction between population and nitrogen fertilizers. No significant yield differences were recorded in 1960-61. The combined data indicated an optimum population of 8 to 32 thousand plants per acre, with only a 5 per cent yield difference across the population range. High populations encouraged early boll development.
Seasonal variation in reproductive performance of Merino ewes in northern New South Wales
Authors: Barrett JF , Reardon TF , Lambourne LJ
Published: March 2005

Two groups of Merino ewes were observed for five years to determine the variation within years and to make comparisons between years in the numbers of ewes exhibiting oestrus, in fertility, and in lamb birth weights. A group of 35 ewes (continuous), was run constantly with vasectomized rams and services were recorded. From the other (changing) group, a fresh sub-group of 15 ewes was joined with fertile rams every four to six weeks; services were recorded, together with lambing performance and lamb birth weights.Distinct breeding and anoestrous seasons similar to those shown by other workers were observed in both groups of ewes. However, the onset of oestrous activity was a month earlier in the changing ewes than in the continuous ewes.Fertility was low during spring and early summer and reached a maximum in autumn.The birth weight of the lambs appeared to be predominantly influenced by the ewes' nutrition during pregnancy.
The effect of previous and current nutrition on wool production in southern Victoria
Authors: Sharkey MJ , Davis IF , Kenney PA
Published: March 2005

The effect of different planes of nutrition on the wool production of Corriedale wethers at pasture was studied between August 1959 and December 1960. The plane of nutrition was controlled by rate of stocking. The effect of previous nutritional treatment on wool production was slight. It affected wool weight and fibre length for 160 one month and fibre diameter for two months. The differences in current nutritional treatment were accompanied by large differences in wool production except during the spring months. On the highest plane of nutrition the wool production showed little seasonal variation, apart from an initial increase in production during the autumn. On the medium and low planes of nutrition wool growth declined substantially in autumn and winter and increased again in spring. The mean fibre diameter of the wool that was clipped frequently was greater than that of fleece wool obtained from the opposite midside at shearing. Further, in the groups on medium and low planes of nutrition estimates of fleece weight based on the combined weight of periodical clippings were greater than actual fleece weights. It is concluded that, in the dry Victorian summer, wool production is influenced by the plane of nutrition in the previous spring for a short period only, and that in autumn and winter it is dependant almost entirely on the feed immediately available.
Performance of pasture grasses in mixtures with Townsville lucerne at Katherine, N.T
Authors: Norman MJT
Published: March 2005

At Katherine, N.T., between 1959-60 and 1961-62, the performance of Townsville lucerne alone and of mixtures of Townsville lucerne with Gayndah buffel grass, Biloela buffel grass, birdwood grass, and Sorghum almum was compared at three frequencies of wet-season cutting. The two most satisfactory mixtures, Townsville lucerne with Gaynahh buffel and birdwood grass, differed little in performance. Over three years, their average dry matter production exceeded that of Townsville lucerne alone by 45 per cent, but average nitrogen production was not appreciably greater than that of the pure legume pasture. Biloela buffel grass is considered to be an unsuitable companion grass for Townsville lucerne because of its competitive power. After three years, the dry matter contribution of the legume in Biloela buffel mixtures was only 18 per cent under the most favourable cutting treatment. The Sorghum almum mixture gave the highest dry matter yield in the first year, but the grass did not survive well, and by the third year the pasture was mainly Townsville lucerne. Sorghum almum may be useful in providing bulk in the early years of an intended pure legume pasture. The role of a perennial grass component in Townsville lucerne pastures is discussed.
A preliminary report on selenium and animal health in Western Australia
Authors: Gardiner MR , Armstrong J , Fels H , Glencross RN
Published: March 2005

White muscle disease in Western Australia appears to be a sporadic disease, fundamentally related to selenium deficiency but in the main limited to young sheep subjected to other concurrent stresses. Whether the complicating stress condition acts primarily at a nutritional level or whether if affects associated endocrine or metabolic pathway is uncertain from present evidence, although it is possible that both mechanisms may be involved. The disease is restricted to the southwestern agricultural districts, having rainfalls of greater than 20 inches. A much greater than average rainfall during the early winter growth stages of subterranean clover, followed a dry August and September, was common to both years (1960 and 1961) during which WMD was first widely recognized and may be ecologically significant in winter outbreaks. There are two peaks of incidence--one in late winter and early spring, affecting young lambs running mainly on subclover pastures, and the other in the summer, affecting weaners and hoggets fed cereal stubble, hay and grain. A survey of these feeds suggests that tehy are very often low in selenium, and may frequently contain less than 0.03 p.p.m. (dry matter) which is proposed as a critical level. However, many flocks grazing pastures containing less than this amount of selenium appear healthy. Ten trials were carried out in the affected area in 1960-61 to test the effect of selenium on lamb or weaner rate of growth Only one trial produced evidence of a significant response although one other suggested that an improvement had taken place. Five trials to determine the value of selenium in improving ewe fertility and early lamb survival were also conducted. The. results of two of them suggested that some improvement could be achieved. Vitamin E also appeared useful in the fertility trials. The soil and plant selenium backgrounds, insofar as thy are known in Western Australia, are discussed in relation to the pattern of outbreaks. Certain factors in the changing agricultural practices are mentioned as probable contributors, notably an increase in sheep stocking rates and heavier application of superphosphate.
The mode of pollination in strawberry clover (Trifolium fragiferum)
Authors: Morley FHW
Published: March 2005

A technique for emasculation and crossing strawberry clover (Trifolium fragiferum) is described. Contrary to reports in the literature this species is predominant4 self-incompatible. A small proportion of plants may set a few seeds on selfing. If seed-set is to be maximal a dense population of pollinating insects such as honey bees is necessary. Commercial seed yields may be greatly improved steps are taken to assure cross pollination.
Root growth of subterranean clover on some acid sandy soils in Victoria
Authors: Kehoe JK , Curnow B
Published: March 2005

Dressings of lime at 10 cwt an acre or more, are essential for the growth of subterranean clover on some acid sand soils in southern Victoria. Clover root growth is very restricted in these soils without lime. In glasshouse trials the clover roots were concentrated in the lime treated portions of the soil. Superphosphate placement, also affected the location of the roots. Aluminium has been reported in the literature for many years as a cause of inhibited root growth. The relation between the level of exchangeable aluminium found in limed and unlimed soils and subterranean clover root growth in glasshouse trials is reported in this paper.
The residual effect of molybdenum fertilizer on improved pastures on a prairie-like soil in sub-tropical Queensland
Authors: 't Mannetje L , Shaw NH , Elich TW
Published: March 2005

The residual effect of molybdenum fertilizer applied to sown pasture was examined in a pot experiment ussing Phaseolus lathyroides L, and Medicago sativa L. as test plants. The beneficial effect of a field application of 4 ounces of sodium molybdate an acre did not last for more than three or four years.
The effects of grazing on topfeed in central Australia
Authors: Chippendale GM
Published: March 2005

A system of recording grazing effects on edible trees and shrub is described. Results of observations using this method are recorded. Acacia aneura and Atalaya hemiglauca are the topfeed species most grazed in Central Australia, but several less common species, Ventilago viminalis, Eremophila longifolia and Santalum lanceolatum are more palatable. A pat soft leaf is preferred by graying cattle, but spines and viscid or oily leaves are deterrents.
A comparison of Queensland whale meals and fish meal as a protein supplement for grain-fed pigs
Authors: Todd ACE
Published: March 2005

Queensland whale meat meal and whale meat and bone meal were compared with South African fish meal as a protein supplement to a sorghum meal diet for pigs. Results were assessed & the growth of Large White pigs over a four month period. Whale meat meal was as efficient in promoting growth at a slightly lower cost than the fish meal. Whale meat and bone meal produced lower gains at a higher cost.
A comparison of two methods of artifical breeding in sheep
Authors: Salamon S , Morrant AJ
Published: March 2005

A test at Trangie Experiment Station in 1958 compared two techniques afartificial breeding of Merino ewes; technique A incorporating practices generally used in Australia and technique E based on central European practices. The techniques differed in methods of detection of oestrus, collection of semen, number of inseminations within one oestrus, and type of inseminating equipment. Paddock teasing (A) using raddled vasectomised rams proved more efficient for detecting ewes in oestrus than yard teasing (E). Semen collected in the artificial vagina was about twice as dense as the semen collected by electro-ejaculation. Volume and motility were similar in both methods. There was a 25 per cent higher conception rate in elves inseminated with technique E. This was partly offset by the lower efficiency of detection of oestrus, giving a nett advantage in lambing rate of 16 pm cent of ewes joined in favour of the European technique. Most of this difference is attributed to the better quality semen obtained with the artificial vagina.
Losses of nitrogen and other soil constituents from two soils in filled-in lysimeters
Authors: Drover DP
Published: March 2005

The results of an eight year lysimeter study conducted at Muresk, Western Australia, are presented. The lysimeters contained two soils, a lateritic sandplain and a noncalcic brown soil, upon which various agronomic treatments were imposed. Mean annual leaching losses of nitrate-nitrogen from the sandplain soil were 4 to 7 lb N per acre under fallow and 6 lb N per acre from subterranean clover pasture. Losses of nitrate-nitrogen from wheat, either with added urea or clover residues (equivalent to 60 lb N per acre) were much higher, viz, 14 to 21 lb N per acre. From the noncalcic brown soil, losses under fallow were 3 to 6 lb N per acre, under clover pasture 2 lb N per acre, and under wheat, either with urea or clover residue added, 4 to 19 lb N per acre. For the sandplain soil, mean annual losses per acre of constituents other than nitrogen were 6 lb K ; 13 lb Ca ; 5 lb Mg ; less than 0.2 lb P ; and 2 to 7 lb S. For the noncalcic brown soil the losses were much lower, viz., 1 lIb K ; 7 lb Ca ; 3 lb Mg; less than 0.2 lb P ; and 0 to 7 lb S. The leaching losses of K, Ca and Mg were related to plant cover, being higher under wheat than under fallow, particularly with the sandplain soil. A n attempt was made to relate changes in nitrogen content of the surface soil at the end of the experiment to the net gain (input minus output) of nitrogen over the same period. This approach was unsatisfactory due largely to the statistical errors associated with soil sampling.
The effect of sowing rate on the yield and composition of wheat grown on soils of high fertility in southern New South Wales
Authors: Colwell JD
Published: March 2005

The effects of the different sowing rates of 20, 40, and 60 lb of seed an acre on the yield, bushel weight, composition, and response to fertilizers, of wheat grown on soils of high fertility has been studied in seven field experiments in the wheat-belt of southern New South Wales. Seasonal conditions ranged from drought to lush growing conditions and in addition one experiment was irrigated to reduce the effects of moisture stress on plant growth. Yields ranged from 10 to 70 bushels of wheat an acre and fertilizer treatments gave both positive and negative effects. For the wide range of growth conditions, variation in seeding rate had only small and non-significant effects on grain yields, with the exception of the irrigated experiment where a consistent trend indicated the need for higher seeding rates for maximum yield. Effects of the seeding rates on grain size and composition and fertilizer response, were negligible. Losses in potential grain yield, caused by the exhaustion of soil moisture reserves by excessive vegetative growth of high fertility soils before grain development has been completed, does not seem to be reduced appreciably by the use of low seeding rates.
Salt tolerance trials with forage plants in south-western Australia
Authors: Rogers AL , Bailey ET
Published: March 2005

A number of forage plants, including reputed salt tolerant species, were tested on a saline-alkali soil at Kojonup, Western Australia. Some annual species gave initial promise but were relatively short-lived in sward conditions. Two perennial grasses, Agropyron elongatum (C.P.I. W296), and Puccinellia capillaris (C.P.I. 15034), persisted well in test plots and field trials. They provided good ground cover and some grazing on land previously thought to be of little value and a potential erosion hazard.
The surgical dehorning of Merino ram lambs
Authors: Dun RB
Published: March 2005

A rapid technique for surgically removing the horn buds of two to eight day old ram lambs was developed. Although the operation destroyed the bony horn core, loosely attached horn like growth were produced by the skin which grew in over the horn sites. Horn growth was not entirely eliminated even when a second operation was carried out as soon as the first had healed (one month). The horn sites of dehorned sheep were often struck by the sheep blowfly. The phenotype of the genetically polled ram could not be duplicated by surgical means.
Effects of nitrogen deficiency and soil moisture stress on growth of pasture grasses at Samford, south-east Queensland. 1. Results of field experiments
Authors: Henzell EF , Stirk GB
Published: March 2005

Two field experiments were carried out at Samford during 1958, 1959, and 1960 using three grasses, nitrogen fertilizer, and supplementary irrigation. Attention was concentrated on grass growth during September to December, a period that is particularly important for livestock that have been grazed on poor quality feed during winter. Nitrogen deficiency was more important than soil moisture stress in limiting growth of grass under natural rainfall. Nitrogen fertilizer caused large increases in yield each year, and maximum yields above 10,000 lb of d y matter an acre were produced by uninterrupted growth up to December or January-four or five times the yields of the unertilized plots. Differences between the yields of the three grasses were small compared with the size of the nitrogen response. In the spring of 1960-61, which was the driest of the three seasons during this investigation, soil moisture stress reduced growth of nitrogen-fertilized Rhodes grass (Chloris gayana Kunth.) up to mid-December one-third. It was observed that fertilized Rhodes grass withdrew water more rapidly and to a greater depth than Rhodes grass without added nitrogen.
Effects of nitrogen deficiency and soil moisture stress on growth of pasture grasses at Samford, south-east Queensland. 2. Calculation of the expected frequency of dry periods by a water budget analysis
Authors: Henzell EF , Stirk GB
Published: March 2005

A water-budget analysis was carried out using the Penman formula to assess the long-term effectiveness of rainfall at Samford. The analysis successfully predicted the occurrence of every important period of soil moisture stress that was recorded by direct measurement during a field experiment. It tended to over-estimate the length of dry periods, but the calculated drought days were related reasonably closely to effects on grass growth. Analysis of 100 years' rainfall, using the records for Brisbane and Samford, predicted that periods of soil moisture stress will occur during the months of October, November and December in slightly more than half the years at Samford. It was calculated that the average effect of dry weather between September 1 and December 1 would be to reduce yields of nitrogen-fertilized Rhodes grass (Chloris gayana Kunth.) by about 20 per cent. A major depression of yield by, drought, i.e. a reduction to less than 50 per cent of yield with adequate water, is expected with an average frequency of slightly less than 1 year in 10. Under the climatic conditions of Samford there seems to be little justification for supplementary irrigation of nitrogen- fertilized grasses. It is suggested that water resources could be better used on pasture legumes such as white clover.
The germination of buffel grass (Cenchrus ciliaris) seed after burial in a Central Australian soil
Authors: Winkworth RE
Published: March 2005

Batches of buffel grass seeds, which had been sown near Alice Springs, N.T. at the usual depth of about one inch, were recovered at increasing intervals. Germination percentages were compared with those of seeds stored in the laboratory for the same periods. At the time of sowing 30 per cent germination was obtained. This level was maintained in the soil for eight months, followed by, a sharp decline to 10 per cent which was maintained for another two years. Stored seed showed an increase to 94 per cent germination in the 8 to 18 month period. The implications are discussed in relation to seed dormancy.
Correction - Paspalum plicatulum Michx. - two useful varieties for pastures in regions of summer rainfall
Authors: Bryan WW , Shaw NH
Published: March 2005

Paspalum plicatulum is a tufted perennial grass adapted to regions of summer rainfall. It is drought tolerant but damaged by frost. Under favourable conditions it is capable of high yields of dry matter (up to 11 tons an acre a year). It is persistent under grazing, tolerant of a range of management systems, and liveweight gains in cattle of 200 lb an acre a year have been recorded. It produces useful yields when the nitrogen supply is relatively low and is capable of combining well with legumes. Two varieties have been released in Queensland for farm trial. They differ little in performance but are distinct in habit and may fill different ecological niches.
The effect of lambing performance on the face cover of ewes
Authors: Dun RB , Clinton BH , Crofts TH , Furner JOC , Godlee AC , Hall HP , May ES , Pye ID , Tucker MJ
Published: March 2005

Face cover was scored on 1979 maiden ewes mated on seven commercial properties in New South Wales. Results from four muffled flocks (full range of face cover scores) showed a small regression of percentage ewes wet on face cover scored prior to mating (b = -2.9, P<0.01). There was no relationship between these measurements in three open faced flocks (no ewes with face cover above score 4). A second score for face cover, given when the ewes had lambs at foot, was very strongly related to percentage wet ewes (b = -7.5, P<0.001, for muffled flocks and b = -6.3, P<0.01, for open faced flocks). The importance of time of scoring in determining the strength of the relation between reproductive performance and face cover, was caused by wet ewes dropping 0.6 grades in average face cover score between mating and marking. Dry ewes maintained their level of face cover.
The influence of nitrogen supply on the fertility of the wheat ear
Authors: Single WV
Published: March 2005

Wheat plants were grown at different nitrogen levels that were raised to a uniformly high plane at varying intervals. Nitrogen starvation drastically reduced the number of spikelets initiated on the first ear, but had less effect on the number of florets initiated per spikelet. Final spikelet number was fixed at or about the double ridge stage, but in most cases the overall fertility of the ear was not determined until several weeks later.
Sampling for soil moisture measurements
Authors: Fox WE , Page-Hanify DS , Cullinane RE
Published: March 2005

A method of gravimetric moisture sampling that eliminates subsampling is suggested. Details of construction of the digging implement and depth control instrument are given. A test of the suggested method and equipment as against standard equipment is described. The result of this test showed that the method described significantly reduced the error in gravimetric moisture sampling due to loss of water while subsampling.
The effect of leaf removal on yield attributes of safflower
Authors: Beech DF
Published: March 2005

At Kimberley Research Station, three-quarters, one-half, and one-quarter of the leaves of drill-sown plots of irrigated safflower (Carthamus tinctorius L.) were removed at the late elongation stage, starting from the base of the plant, to simulate attack by the larvae of Prodenia litura F. Increasing severity of leaf removal had a progressively detrimental effect on seed yield and oil content ; however, removal of three-quarters of the leaves only reduced the yield of oil per acre by half.
Some input-output relations in peanut cultivation at Katherine, N.T
Authors: Basinski JJ , Phillips LJ , Norman MJT
Published: March 2005

In an experiment at Katherine, Northern Territory, in 1961-62 and 1962-63 the response of peanuts to variation in ploughing depth, frequency of inter-row cultivation, and seeding rate was measured. This agronomic study was combined with measurements of rates of work and fuel consumption under comparable conditions for the tillage operations involved. From these data were calculated the break-even prices for peanuts above which the yield response offset the additional cost of the more intensive treatment, i.e., deeper ploughing, more frequent inter-row cultivation, or higher seeding rate. Increasing the depth of ploughing from two to eight inches, the number of inter-row cultivations from one to three and the seeding rate from 30 to 45 lb an acre were all profitable at prices that would justify peanut production in the Katherine area.
The lint percentage of cotton in the Ord River Valley
Authors: Thomson NJ
Published: March 2005

Time of harvest during crop ripening was accompanied by large differences in lint percentage of cotton in the Ord River Valley. Lint percentage generally rose at least 3 per cent from first to last harvest. Varieties showed a wide range in lint percentage. Varietal values remained very stable between seasons in a three year trial but in two out of three seasons there was a pronounced time of sowing effect, lint percentage rising with sowing from November to at least February. Significant variety x time of sowing interactions were recorded. In three trials nitrogen fertilizer reduced lint percentage, though there was no consistent relationship between rate of nitrogen application and lint percentage decrease. Spacing, phosphorus, potash, and defoliation had no direct effect on lint percentage.
The effect of krilium soil conditioner on the yield of wheat
Authors: Stoneman TC
Published: March 2005

A field trial investigated the effect of improved soil structure on wheat yield. Krilium, a synthetic polyelectrolyte soil conditioner, was used to improve structure. The water stability of the soil aggregates was significantly increased on the plots treated with the conditioner. The conditioner treated plots also had significantly higher yields and 1000-grain weights than the untreated plots. The effect of the soil conditioner persisted into the year after cropping, when the plots were sown to Barrel Medic (Medicago tribuloides Desr.). The Barrel Medic establishment was significantly greater on the conditioner treated plots.
The aroma of flue-cured tobacco. Sensory testing for the discrimination of varieties
Authors: Thruling N
Published: March 2005

Freshly cured tobacco leaf from a replicated variety trial was scored by a panel of judges according to aroma type and strength, and a combined aroma quality scale of eight points, ranging from strong-objectionable to strong-pleasant, was derived. Statistical analysis of the data was then undertaken to determine the consistency and relative precision of the panel measurements and the degree of varietal discrimination obtainable. Some of the difficulties associated with the subjective evaluation of such material are demonstrated and discussed.
The effectiveness of the Mules operation when carried out in conjunction with lamb marking
Authors: Dun RB , Donnelly FB
Published: March 2005

Seventy-eight Merino ewe lambs were Mulesed in September 1961 at the same time as their tails were docked (Marking Mules). For comparison, 76 lambs from the same drop were Mulesed in December 1961 (Weaning Mules). The modified Mules plus tail strip was used on both occasions. Observations on 13 un-Mulesed lambs showed three fly waves occurring during the course of the experiment -1. Late November-early December 1961-31 per cent of breech and tail strikes ; 2. April-May 1962-31 per cent; 3. September-November 1962-93 per cent. The Marking Mules gave effective protection during the first fly wave. Both operations reduced the incidence of strike during waves 2 and 3, totals of 11.7 and 5.6 per cent of strikes being recorded for the Marking Mules and Weaning Mules respectively. In comparison with the Marking Mules, the Weaning Mules produced slower healing of Mulesing wounds, greater post-operative depression of growth rate and reduced wool production.
Performance of lucerne varieties on the south coast of New South Wales
Authors: Daday H
Published: March 2005

The performances of Hunter River and introduced varieties of lucerne were tested at Milton (south coast of N.S.W.). There were no significant differences in yield between any variety in spring or summer, but Hairy Peruvian, African, and Indian produced significantly more than Hunter River in winter. These introduced varieties could make a valuable contribution to the dairying industry of the south coast of N.S.W.
Carbamate and organophosphorus sprays as alternatives to DDT to control red-legged earth mites (Halotydeus destructor and Penthaleus major)
Authors: Wright WE
Published: March 2005

Four experiments, two conducted in 1962 and two in 1963, are described. Low volume applications of two carbamates, eight organophosphorous compounds, and a quinoxaline miticide were tested for their value in controlling the two species of red-legged earth mites, Halotydeus destructor (Tucker) and Penthaleus major (Duges) alongside the standard DDT treatment of four ounces active ingredient an acre. Two of the organophosphorous compounds, namely azinphos ethyl and 'Imidan' applied at half an ounce active ingredient an acre, were shown to give effective control of both mite species for at least five weeks and can now be recommended as alternative mite control treatments that would eliminate the risk of contamination of meat or animal products by undesirable residues. Since DDT at 2 oz active ingredient an acre gave very effective mite control, this lower dosage may- be useful in lessening the residue risk.
The sensitivity of fruit growth rate to the water balance of the plant
Authors: Till MR
Published: March 2005

It is argued that when the diffusion pressure deficit of the fruit exceeds that of the leaves, the fruit is relatively insensitive to the state of water balance of the plant. The results of a limited number of diffusion pressure deficit measurements of the leaves and fruit of grape vines are presented and indicate that the ripe fruit may be insensitive, but that green fruit is sensitive to the state of the water balance of the plant.
The response of a birdwood grass - Townsville lucerne pasture to phosphate fertilizers at Katherine, N.T
Authors: Norman MJT
Published: March 2005

In an experiment at Katherine, N.T., the response of birdwood grass-Townsville lucerne (Cenchrus setigerus Vahl and Stylosanthes hurnilis H.B.K.) pasture sown on virgin land to levels of superphosphate and Christmas Island rock phosphate dust and to levels of superphosphate subsequently applied annually for three years was measured. There were no significant interactions between initial and annual applications. Initial applications of 2 and 4 cwt an acre superphosphate both gave higher forage yields of dry matter and nitrogen than 2 and 4 cwt an acre rock phosphate over the experimental period. Phosphorus yield of forage was a function of rate rather than of type of fertilizer. Annual superphosphate applications up to 1 cwt an acre increased the dry matter and nitrogen yields of the grass, but not those of the legume, and increased the phosphorus yield of both. The higher proportion of grass at high superphosphate levels was interpreted as a difference in responsiveness of the two species. A regime of 2 cwt an acre superphosphate initially and 1/2 cwt an acre annually produced 90 per cent of what was considered to be the maximum yield.
The effect of nitrogen fertilizers on irrigated cotton at the Kimberley Research Station, north-western Australia
Authors: Thomson NJ
Published: March 2005

Three experiments were carried out at Kimberley Research Station, W.A., between 1959 and 1963 to study the effects of rates and times of applying nitrogen fertilizer to irrigated cotton. Nitrogen applications increased yields in all three experiments but the magnitude of response varied. Response to nitrogen was greater after a short dry season fallow between crops than after a long fallow with accompanying soil nitrification. Very high nitrogen applications produced rank plant growth. The rank growth resulted in inefficient mechanical harvesting and the control of Prodenia litura was made difficult. Plant size was reduced by splitting the nitrogen application but yield was not reduced. Nitrogen applications had no effect on quality but reduced lint percentage slightly.
Seasonal performance of beef cattle on native pasture at Katherine, N.T
Authors: Norman MJT
Published: March 2005

Nine years' data on the liveweight of beef cattle steers from 1 to 4 years of age carried on native pasture at Katherine, N.T., are summarized. Cattle began to gain weight at the start of the main flush of wet season pasture growth, following effective rainfall of two inches or more in the previous fortnight, on a mean date of November 27. Weight gains continued until shortly after the end of the wet season, on a mean date of May 23. Maximum rates of gain were reached in January, maximum rates of loss in November. The mean net annual liveweight gain was only 107 lb. Variation in rates of gain and loss throughout the pear were largely related to changes in the nitrogen content of the pasture.