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131.
Hopp Steven L.; Sinnott Joan M.; Owren Michael J.; Petersen Michael R. 《Canadian Metallurgical Quarterly》1992,106(2):128
Difference limens (DLs) for changes in the temporal position of a pitch peak along a synthetic early-high to late-high coo continuum were measured in 2 Japanese macaques and 2 humans in a low-uncertainty, repeating standard discrimination procedure. Lowest DLs (19–32 msec for monkeys; 相似文献
132.
CL Schmidt OM Hatzfeld A Petersen TA Link G Sch?fer 《Canadian Metallurgical Quarterly》1997,234(1):283-287
The Rieske protein II (Schmidt et al., 1996, FEBS Lett. 388, 43-46) from the thermoacidophilic crenarcheon Sulfolobus acidocaldarius (DSM 639) was expressed in E. coli cells. The full length protein was strictly bound to the E. coli membranes and could only be removed by detergent treatment indicating the presence of a membrane anchor. The iron sulfur cluster was correctly inserted into a fraction of the full length protein and much more effectively into a soluble form created by the deletion of the 45 N-terminal amino acids. The soluble form of the protein displayed the typical spectroscopic properties of a respiratory Rieske protein. The midpoint potential was +375 mV determined by CD redox potentiometry. The presented data demonstrate that the structure of the recombinant protein is very similar or identical to the authentic protein making this a powerful model system for the studies of Rieske proteins by site directed mutagenesis. 相似文献
133.
134.
Bent Srensen 《Solar Energy Materials & Solar Cells》1997,47(1-4)
The paper discusses the role of photovoltaics in current energy scenario work on a local, regional or global scale, for the mid-21st century. 相似文献
135.
Magyar-Moe Jeana L.; Pedrotti Jennifer Teramoto; Edwards Lisa M.; Ford Alicia Ito; Petersen Stephanie E.; Rasmussen Heather N.; Ryder Jamie A. 《Canadian Metallurgical Quarterly》2005,36(4):446
Multicultural training at internship sites is a critical component in the preparation of doctoral-level psychologists, so the quality of this training is of the utmost importance. In the following study, the authors examine multicultural training from the perspective of predoctoral interns and training directors at counseling center sites that offer a major or minor rotation in multicultural therapy. Results suggest that perspectives vary between interns and training directors and that there is a great difference in the type of criteria used by each site as evidence of a major or minor rotation. The need for more standardized criteria to define major and minor rotations and suggestions for the Association of Psychology Postdoctoral and Internship Centers, internship training directors, and prospective interns are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
136.
Bent Wiencke 《International Journal of Refrigeration》2011,34(8):2092-2108
Throughout the past decades, the industrial refrigeration industry has developed various “rule of thumb” methods for sizing gravity liquid separators for ammonia and other common refrigerants. However, to date a uniform systematic approach or an agreeable standard has not been established. For commonly used refrigerants such as ammonia, the large installed base of separators can be used as a benchmark for sizing separators. But, when using a less common refrigerant such as CO2, the designer faces new challenges. In this paper, a systematic approach is presented for sizing horizontal and vertical gravity liquid separators for industrial refrigeration applications. To compute separation velocities and separation distances, a theoretical model is presented. The model is used as a basis for comparison with observations from 85 operating gravity separators surveyed in the field. Criteria and formulas are presented for estimating the required liquid volume for storage. An example is provided demonstrating the use of the methods presented in this paper. 相似文献
137.
Klarskov MB Dam HF Petersen DH Hansen TM Löwenborg A Booth TJ Schmidt MS Lin R Nielsen PF Bøggild P 《Nanotechnology》2011,22(44):445702
We present measurements of the electronic properties of graphene using a repositionable micro four-point probe system, which we show here to have unique advantages over measurements made on lithographically defined devices; namely speed, simplicity and lack of a need to pattern graphene. Measurements are performed in ambient, vacuum and controlled environmental conditions using an environmental scanning electron microscope (SEM). The results are comparable to previous results for microcleaved graphene on silicon dioxide (SiO(2)). We observe a pronounced hysteresis of the charge neutrality point, dependent on the sweep rate of the gate voltage; and environmental measurements provide insight into the sensor application prospects of graphene. The method offers a fast, local and non-destructive technique for electronic measurements on graphene, which can be positioned freely on a graphene flake. 相似文献
138.
Realization of the cloud computing infrastructure requires access to data anywhere, anytime at any device at a sufficient
perceived quality of service. Many Western European countries, such as Denmark, have a high percentage of individuals (inhabitants
and companies) that has access to broadband internet via cable, satellite and mobile. This gives a unique position in roll-out
and deploying intelligent cloud based services that can be applied for a number of purposes, but where lack of sufficient
capacity/quality and IT readiness will be barriers in realization of the “Global Information Multimedia Communication Village
(GIMCV)”. Broadband is here defined as more than 2 Mbps. In this paper, the combination of e-commerce, cloud computing and
broadband infrastructure has our focus, and its unique possibilities for the overall IT society. However, it is also about
a significant number of Small and Medium sized Enterprises (SMEs) that today applies manual billing systems or Excel like
systems in combination with severe lacks of sufficient IT skills. This means that the most commonly used systems are the ones
requiring the most of our time. Therefore, the move for the SME towards e-commerce and electronic processes has a significant
economical potential for the SMEs. E-commerce and other internet based services will simplify their business, and hence allow
the SMEs to focus on their core business which was their raison d’être. In addition to this can be added other fundamental
IT systems that will help their business, but that is outside the scope of this paper. Furthermore, this paper focuses on
infrastructural barriers and cloud computing; not only focusing on bandwidth, but also the entire issue of service offering.
Services offered via cloud computing solutions will minimize the SMEs investment in own hardware (HW), software (SW) and maintenance.
The focus is also the upgrade to a superior infrastructure that provides the platform for efficient cloud computing, for e-commerce,
and beyond. 相似文献
139.
Grate JW O'Hara MJ Farawila AF Douglas M Haney MM Petersen SL Maiti TC Aardahl CL 《Analytical chemistry》2011,83(23):9086-9091
A sample preparation sequence for actinide isotopic analysis by thermal ionization mass spectrometry (TIMS) is described that includes column-based extraction chromatography as the first separation step, followed by anion-exchange column separations. The sequence is designed to include a wet ashing step after the extraction chromatography to prevent any leached extractant or oxalic acid eluent reagents from interfering with subsequent separations, source preparation, or TIMS ionization. TEVA resin and DGA resin materials, containing extractants that consist only of C, N, O, and H atoms, were investigated for isolation of plutonium. Radiotracer level studies confirmed expected high yields from column-based separation procedures. Femtogram-level studies were carried out with TIMS detection, using multiple monoisotopic spikes applied sequentially throughout the separation sequence. Pu recoveries were 87% and 86% for TEVA and DGA resin separations, respectively. The Pu recoveries from 400 μL anion-exchange column separation sequences were 89% and 93% for trial sequences incorporating TEVA and DGA resin. Thus, a prior extraction chromatography step in the sequence did not interfere with the subsequent anion-exchange separation when a simple wet ash step was carried out in between these column separations. The average measurement efficiency for Pu, encompassing the chemical separation recoveries and the TIMS ionization efficiency, was 2.73% ± 0.77% (2σ) for the DGA resin trials and 2.67% ± 0.54% for the TEVA resin trials, compared to 3.41% and 2.37% (average 2.89%) for two control trials. These compare with an average measurement efficiency of 2.78% ± 1.70%, n = 33 from process benchmark analyses using Pu spikes processed through a sequence of oxalate precipitation, wet ash, iron hydroxide precipitation, and anion-exchange column separations. We conclude that extraction chromatography can be a viable separation procedure as part of a multistep sequence for TIMS sample preparation. 相似文献
140.
The endogenous nonapeptide bradykinin is a powerful substance which activates nociceptors, resulting in the sensation of pain in man. We used a newly developed non-radioactive method to detect bradykinin binding sites in isolated dorsal root ganglion cells with gold-labelled bradykinin. In a subpopulation of cells, gold-labelled bradykinin was bound in different quantities. The proportion of somata with bradykinin binding markedly depended on the length of time in culture. After 0.75 days, bradykinin was bound to 43% of somata. This proportion increased to 85% after 1.75 days and then decreased to 27% after 5.75 days. Bradykinin was bound to cells of all sizes, ranging from 40 to 2000 microns2 with a maximum of 200-300 microns2. In some cells, binding was also seen along the processes. No correlation was found between the soma size and the density of bradykinin binding. Blocking the bradykinin binding at the B1 receptor with (Des-Arg10)-Lys-bradykinin and at the B2 receptor with D-Arg(Hyp3-Thi5.8-D-Phe7)-bradykinin, respectively, revealed that in 0.75-day-old cultures no or only a very small amount of B1 receptors are present. In 1.75-day-old cultures, the marked increase in the proportion of cells with positive bradykinin binding is due to a de novo expression of the B1 receptor subtype and an up-regulation of the B2 receptor subtype. The selective or combined addition of specific B1 and B2 receptor ligands revealed that both receptor subtypes are co-localized. These data show that cultured sensory neurons express not only B2, but during a short period of time in culture also B1 receptors. The data allow us to hypothesize that a transient increase in bradykinin receptor expression might be caused by cell injury due to disruption of the axon. The injury-induced up-regulation of the receptor in vivo could cause physiological reactions. 相似文献