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1.
This article will review the development of the Fe–Ga (Galfenol) alloy system for magnetostriction applications including
work on substitutional ternary alloying additions for magnetic property enhancement. A majority of the alloying addition research
has focused on substitutional ternary elements in Bridgman grown single crystals with the intent of improving the magnetostrictive
capability of the Galfenol system. Single crystals provide the ideal vehicle to assess the effectiveness of the addition on
the magnetostrictive properties by eliminating grain boundary effects, orientation variations, and grain-to-grain interactions
that occur when polycrystals respond to applied magnetic fields. In almost all cases, ternary additions of transition metal
elements have decreased the magnetostriction values from the binary Fe–Ga alloy. Most of the ternary additions are known to
stabilize the D03 chemical order and could be a primary contribution to the observed reduction in magnetostriction. In contrast, both Sn and
Al are found to substitute chemically for Ga. For Sn additions, whose solubility is limited, no reduction in magnetostriction
strains are observed when compared to the equivalent binary alloy composition. Aluminum additions, whose effect on the magnetoelastic
coupling on Fe is similar to Ga, result in a rule of mixture relationship. The reviewed research suggests that phase stabilization
of the disordered bcc structure is a key component to increase the magnetostriction of Fe–Ga alloys. 相似文献
2.
KR Porter PL Summers D Dubois B Puri W Nelson E Henchal JJ Oprandy CG Hayes 《Canadian Metallurgical Quarterly》1993,48(3):440-446
A polymerase chain reaction (PCR) assay was developed to rapidly detect and identify West Nile (WN) virus. The RNA from seven isolates of WN virus from six countries and four other flaviviruses (Kunjin, Japanese encephalitis, St. Louis encephalitis, and yellow fever viruses) was reverse-transcribed (RT) and amplified by PCR. The nucleotide sequences of the amplified products were determined by a rapid, automated DNA sequencing method. The WN virus RT/PCR assay detected the target gene segment of sequencing method. The WN virus RT/PCR assay detected the target gene segment of isolates from both the African-Middle Eastern group and the Indian group with a sensitivity of approximately 0.05 pg of viral RNA. Kunjin virus was the only other flavivirus tested that produced a band of the appropriate size. Five of seven WN virus isolates showed 92-98% homology in the nucleotide sequence of their PCR products. The sequence of one isolate was virtually identical to the published sequence of the Nigerian isolate (99.5% homology). No correlation was established between the degree of nucleotide homology, geographic location, time of isolation, or source of the isolates. 相似文献
3.
4.
The Wabash River Integrated Methanol and Power Production from Clean Coal Technologies (IMPPCCT) project is investigating an Early Entrance Coproduction Plant (EECP) concept to evaluate integrated electrical power generation and methanol production from coal and other carbonaceous feedstocks. Research, development and testing (RD&T) that is currently being conducted under the project is evaluating cost effective process systems for removing contaminants, particularly sulfur species, from the generated gas which contains mainly synthesis gas (syngas), CO2 and steam at concentrations acceptable for the methanol synthesis catalyst. The RD&T includes laboratory testing followed by bench-scale and field testing at the SG Solutions Gasification Plant located in West Terre Haute, Indiana. Actual synthesis gas produced by the plant was utilized at system pressure and temperature for bench-scale field testing. 相似文献
5.
Transcortical dialysis was employed to investigate the effects of subcutaneous (s.c.) injections of RJR-2403 (1.2-7.2 mumol/kg) on extracellular levels of acetylcholine (ACh), norepinephrine (NE), dopamine (DA), and serotonin (5-HT) in rat. Systemic administration of RJR-2403 produced a 90% increase of cortical extracellular ACh levels that persisted for up to 90 minutes after injection. Norepinephrine and DA release were increased 124% and 131% above basal values, respectively. Serotonin (5-HT) levels in the dialysate were also significantly elevated by RJR-2403 (3.6 mumol/kg, s.c.) 70% above baseline at 90 minutes post-injection. Comparison of these responses to those of (-)nicotine from a previous study reveals little difference between the two compounds in their ability to influence cortical neurotransmitter release following systemic administration. 相似文献
6.
RM Summers J Andrasko-Bourgeois IM Feuerstein SC Hill EC Jones MK Busse B Wise KE Bove BA Rishforth E Tucker TL Spray JM Hoeg 《Canadian Metallurgical Quarterly》1998,98(6):509-518
Hepatitis C chronically infects approximately 1.5% of Americans and is the most common clinical problem facing hepatologists. Since the virus was initially described in 1989, development of an effective therapy has been challenging. Although several different therapeutic agents have been used, no therapy has been shown to reliably eradicate the virus. Interferon-alpha, a cytokine with immunostimulatory and anti-viral properties, has become the therapy of choice for patients with chronic hepatitis C infection. Trials assessing the efficacy of interferon-alpha have characterized host and viral factors predictive of responses to treatment. A thorough understanding of these predictive factors is requisite to providing cost-effective therapeutic decisions for the patient with chronic hepatitis C infection. 相似文献
7.
H. Khim Boo Bela K. Mikofalvy James W. Summers W. Alan Sell Don H. Mittendorf 《乙烯基与添加剂工艺杂志》1992,14(3):140-144
The separation of PVC from contaminants is one of the most important steps in recycling PVC. Earlier works have shown that one can separate PVC from other polymers by using the X-ray fluorescence technique. However, in many cases, even after careful separation, there is a remaining impurity level of about 0.1% due to the limitations of the separation processes. In many applications, impurities, particularly nonmeltables, cause defects in the PVC matrix and must be removed for best performance and appearance. Melt filtration appears to be the best technique to remove the nonmeltable impurities. 相似文献
8.
The kinetics of creep and fatigue crack growth in PVC pipe were studied in order to develop a methodology for predicting long‐term creep fracture from short‐term fatigue tests. Fatigue and creep crack propagation followed the conventional Paris law formulations with the same power 2.7: da/dt = AfΔK2.7I and da/dt = BK2.7I, respectively. The activation energy for creep crack propagation, obtained from the temperature dependence of the Paris law prefactor, allowed extrapolation of high temperature creep fracture to low temperature creep crack growth rates. The activation energy for fatigue crack propagation was much lower than that for creep. Therefore, fatigue and creep could not be directly correlated by using the prefactor in the covenentional Paris law formulations. Furthermore, a unique value of the Paris law prefactor did not describe frequency and R‐ratio (amplitude) effects in fatigue crack propagation. Nevertheless, conformity of crack growth rates measured under all conditions to the same Paris law power suggested that correlation should be sought in alternative formulations of the crack growth rate. 相似文献
9.
A fixed bed is gradually exhausted from top to bottom without backwashing; however, backwashing can rearrange the concentration
gradient in the bed. After backwashing, saturated particles which are located at the top of the bed are homogeneously distributed
in the bed. The used model to predict adsorption and backwashing effect of organic component is the plug flow pore surface
diffusion model (PFPSDM). A sensitivity analysis was performed to determine which parameters have the greatest impact on the
model results for components which can represent various organics. In addition, the effects of backwashing were examined by
rearranging concentration gradient. For single component sensitivity analysis, the molecular weight was an important parameter.
The breakthrough of the smaller molecular weight component was impacted more by backwashing. The SPDFR showed a significant
impact on the breakthrough pattern. When surface diffusion was the dominant mechanism, high SPDFR, the breakthrough profile
was sharper than when pore diffusion was dominant, low SPDFR. The adsorbability was an important parameter in determining
the breakthrough pattern. As expected, the strongly adsorbable component showed the later breakthrough. Backwashing yielded
earlier breakthrough for all single components and multi-components examined. 相似文献
10.
The Peel-Harvey estuary on the Swan Coastal Plain, Western Australia has become eutrophic partly because of the leaching of fertiliser phosphorus from sandy soils. The acid, coarse textured sandy soils are predominantly quartz, have a low iron and aluminium content and do not retain phosphorus. Red mud, derived from bauxite, is a by-product of the alumina industry and has the ability to retain phosphorus. Retention of phosphorus is enhanced when the red mud is neutralised with gypsum. Red mud has been suggested as a soil amendment to reduce phosphorus leaching.To investigate the reduction in the leaching of phosphorus from soils amended with red mud, weirs were constructed at the outlets from a pair of catchments to quantify the amount of phosphorus in the streamflow. Both catchments were deep grey Bassendean sand. One of the catchments was treated with 80 t/ha of red mud which had been neutralised with waste gypsum from the phosphate industry. The red mud was applied to the soil surface using conventional fertiliser spreading equipment. The other catchment was untreated.The red mud reduced phosphorus loss by 70% from 13.8 kg/ha on the untreated catchment, to 4.2 kg/ha on the treated catchment. Both catchments were treated with 20.4 kg/ha of phosphorus as superphosphate. The catchment treated with red mud also received a further 41.5 kg/ha of phosphorus from the phosphogypsum that was used to neutralise the red mud.Our results show that red mud reduces phosphorus leaching and is potentially a nutrient management option in sandy soils. Red mud has the potential to reduce the impact of agriculture on the estuarine environment and has implications for the continued expansion and intensification of agriculture in the Peel-Harvey catchment. 相似文献