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排序方式: 共有496条查询结果,搜索用时 0 毫秒
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Letters to the editor 总被引:6,自引:0,他引:6
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Norman F. Haard Nancy Kariel Gene Herzberg L. A. Woodrow Feltham Karl Winter 《Journal of the science of food and agriculture》1985,36(4):229-241
Fish silage was prepared from 96.5% offal obtained from Atlantic cod fillet processing and 3.5% (by wt) formic acid. The fish silage became an homogeneous liquid of low viscosity in 36–58 h at 20°C; however, the oil and protein components continued to be hydrolysed for several months. Addition of formaldehyde to fish silage (0.25 or 0.39% by wt) after liquefaction was complete, served to prevent continued protein hydrolysis and oxidative rancidity of the oil. It also decreased the development of ‘off-odours’, and the formation of total volatile bases. Fish silage was readily absorbed by hay at a ratio of 1.5 parts silage to 1.0 parts hay by weight; the product is referred to as ‘haylage’. Voluntary intake by wethers of ‘haylage’ prepared from de-oiled, formaldehyde-treated fish silage was better than for ‘haylage’ prepared from untreated fish silage. The crude protein content of ‘haylage’ rations was more than satisfactory for fattening lambs, although the energy content of ‘haylage’ rations may be a limiting factor. Retention of fish oil in the silage to increase the energy content of rations was unsuccessful because voluntary feed intake was depressed. The addition of formaldehyde to fish silage is advantageous when the product is to be fed to ruminant livestock since protein and lipid degradation in the feed, and also possibly in the rumen, are minimised and voluntary intake of ‘haylage’ by sheep is increased. 相似文献
5.
Investigation of driving performance, vection, postural sway, and simulator sickness in a fixed-based driving simulator 总被引:1,自引:0,他引:1
This paper reports the results of a pilot study conducted to determine whether there is a relationship between simulator sickness and measures of driver inputs, vection, and postural sway, in a fixed base driving simulator. Seven males and four females performed a series of alternating left and right turns (20 each), with straigth-aways inbetween. The task was designed to promote experiences of circular and linear vection, and associated sway. It was hypothesized that greater driver inputs (i.e., steering wheel and braking activity; deviation from the centerline) would correlate: with reports of vection and measures of postural sway. Ten of the eleven subjects reported moderate sickness, which precluded any statistical comparisons between “sick” and “not sick” however, there was a significant tendency for persons who reported vection to also report sickness. There were no gender differences in reported incidence of vection or sickness, however, males tended to exhibit greater lateral velocity. The next phase of investigation will necessitate reducing the strength of the stimulus (i.e., require less turns) to increase variability of sickness scores amongst subjects and permit comparisons between “sick” and “not sick.” Measurement considerations include increasing the sensitivity of vection ratings, and examination of the timecourse for the development of postural sway. 相似文献
6.
Brody Gene H.; Ge Xiaojia; Kim Su Yeong; Murry Velma McBride; Simons Ronald L.; Gibbons Frederick X.; Gerrard Meg; Conger Rand D. 《Canadian Metallurgical Quarterly》2003,71(2):211
Data from 296 sibling pairs (mean ages 10 and 13 years), their primary caregivers, and census records were used to test the hypothesis that African American children's likelihood of developing conduct problems associated with harsh parenting, a lack of nurturant-involved parenting, and exposure to an older sibling's deviance-prone attitudes and behavior would be amplified among families residing in disadvantaged neighborhoods. A latent construct representing harsh-inconsistent parenting and low levels of nurturant-involved parenting was positively associated with younger siblings' conduct disorder symptoms, as were older siblings' problematic attitudes and behavior. These associations were strongest among families residing in the most disadvantaged neighborhoods. Future research and prevention programs should focus on the specific neighborhood processes associated with increased vulnerability for behavior problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Anil Kumar William R. Leo Lawrence Green Gene L. Woodruff 《Journal of Fusion Energy》1989,8(1-2):107-126
The neutron spectra transmitted across a fission-suppressed hybrid blanket and its components, driven by a low intensity 14 MeV Haefely neutron generator, were measured with a 2×2 NE213 detector at LOTUS facility. These experiments have been analyzed with 2D and 3D codes DOT3.5 and MCNP, respectively. The spectral integrals between 15 to 1 MeV show good agreement among the 2D, the 3D, and the NE213 for 15 cm lead, 18 cm beryllium, and 25 cm graphite slabs. However, there are large discrepancies for 6.2 cm stainless steel and 15 cm lithium carbonate slabs. The assemblies involving two or more of these slabs reflect these tendencies. We observe also considerable disagreement over pointwise spectra for a number of assemblies.Work done while on visiting assignment to Institut de Génie Atomique, E.P.F.L. 相似文献
8.
Cheryl M. M. Carey Gene H. Golub Kincho H. Law 《International journal for numerical methods in engineering》1994,37(16):2857-2883
In this paper, a new solution method for the modified eigenvalue problem with specific application to structural dynamic reanalysis is presented. The method, which is based on the block Lanczos algorithm, is developed for multiple low rank modifications to a system and calculates a few selected eigenpairs. Given the solution to the original system Ax = λx, procedures are developed for the modified standard eigenvalue Problem (A + ΔA)x? = λ x?, where
- 1 ΔA = ΣjBSjBT, where Sj = S ∈ ?p × p, p ? n and B ∈ ?n × p is constant for all the perturbations Sj.
- 2 ΔA = ΣiΣj BiSjBiT, where Bi ∈ ?n × p may vary with the pertubations Sj.
9.
Jeffrey T RichardsAndrew C Schuerger Gene CapelleJames A Guikema 《Remote sensing of environment》2003,84(3):323-341
Fluorescence spectral characteristics associated with growth under different irradiance levels, and during rapidly changing lighting conditions, were measured on healthy bean (Phaseolus vulgaris L.) and wheat (Triticum aestivum L.) plants using a laser-induced fluorescence spectroscopy (LIFS) system. The LIFS system was designed as a prototype of a handheld field remote sensing system and used a tripled Nd:YAG laser to produce ultraviolet (UV) excitation photons at 355 nm. Dark-adapted canopies of the bean and wheat plants grown under 150, 300, or 450 μmol m−2 s−1 of photosynthetically active radiation (PAR) exhibited LIFS spectra with higher relative fluorescence intensities than emissions from light-adapted plants at all three light levels. Blue/red and blue/far-red leaf fluorescence ratios for both bean and wheat plants increased dramatically as PAR increased, but red/far-red ratios decreased as PAR increased. Light-adapted plants grown under the three light levels were then subjected to several rapidly changing lighting conditions. Plants were exposed sequentially to 150, 300, and 650 μmol m−2 s−1 PAR from metal halide lamps, followed by a fourth light treatment of 650 μmol m−2 s−1 PAR from a mixture of metal halide and tungsten-halogen lamps. The tungsten-halogen lamps added significant amounts of near-infrared (NIR) irradiation to the background light environment provided by the metal halide lamps. Results indicated that both bean and wheat canopies generally exhibited stable blue, green, red, and far-red fluorescence emissions when plants were exposed to 150, 300, and 650 μmol m−2 s−1 PAR from the metal halide lamps. In contrast, when bean and wheat plants were exposed to the NIR-enriched light supplied by the tungsten-halogen lamps, blue and green fluorescence remained stable, but red and far-red fluorescence increased dramatically immediately after exposure to the NIR photons. However, the increased levels of red and far-red fluorescence observed after exposure to NIR light decreased quickly (within 55 s) and returned to “baseline” levels observed at the start of the rapidly changing light experiments. Results indicate that handheld LIFS instruments can be used for remote sensing of plant canopies under a diversity of lighting conditions including full darkness, dawn and dusk lighting environments, and under rapidly changing light environments similar to those encountered on partly cloudy days. 相似文献
10.
Wenjun Liu Gene E. Ice Bennett C. Larson Wenge Yang Jonathan Z. Tischler J. D. Budai 《Metallurgical and Materials Transactions A》2004,35(7):1963-1967
The three-dimensional (3-D) X-ray crystal microscope is a new nondestructive tool for the 3-D characterization of the mesoscopic
and nanoscopic materials structure. A prototype microscope is installed on beamline 34-ID at the advanced photon source and
has begun initial operation. The prototype microscope has a routine spatial resolution of approximately 0.5 × 0.5 × 1 μm3 and can probe tens to hundreds of microns below a sample surface, depending on the composition of the sample. For each volume
element measured, the microscope can determine between 10 and 16 parameters. The measured parameters are the local crystallographic
phase (1 deg of freedom), the Eulerian angles of crystal orientation (3 deg of freedom), and the plastic and/or elastic strain-tensor
elements (6 to 12 deg of freedom). The time required to collect each volume element varies between 1 and 14 seconds, depending
on the precision of the parameters and the sample complexity. Much faster data acquisition and much better spatial resolution
are certain in the near future. Some initial results are presented to illustrate how the 3-D X-ray crystal microscope can
provide unprecedented information about the 3-D structure of materials.
This article is based on a presentation made at the symposium “Characterization and Representation of Material Microstructures
in 3-D” held October 8–10, 2002, in Columbus, OH, under the auspices of ASM International’s Phase Transformations committee. 相似文献