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排序方式: 共有497条查询结果,搜索用时 10 毫秒
51.
Life cycle environmental assessment of lithium-ion and nickel metal hydride batteries for plug-in hybrid and battery electric vehicles 总被引:1,自引:0,他引:1
This study presents the life cycle assessment (LCA) of three batteries for plug-in hybrid and full performance battery electric vehicles. A transparent life cycle inventory (LCI) was compiled in a component-wise manner for nickel metal hydride (NiMH), nickel cobalt manganese lithium-ion (NCM), and iron phosphate lithium-ion (LFP) batteries. The battery systems were investigated with a functional unit based on energy storage, and environmental impacts were analyzed using midpoint indicators. On a per-storage basis, the NiMH technology was found to have the highest environmental impact, followed by NCM and then LFP, for all categories considered except ozone depletion potential. We found higher life cycle global warming emissions than have been previously reported. Detailed contribution and structural path analyses allowed for the identification of the different processes and value-chains most directly responsible for these emissions. This article contributes a public and detailed inventory, which can be easily be adapted to any powertrain, along with readily usable environmental performance assessments. 相似文献
52.
Relationship between peptide selectivities of human transporters associated with antigen processing and HLA class I molecules 总被引:1,自引:0,他引:1
S Daniel V Brusic S Caillat-Zucman N Petrovsky L Harrison D Riganelli F Sinigaglia F Gallazzi J Hammer PM van Endert 《Canadian Metallurgical Quarterly》1998,161(2):617-624
Efficiency of presentation of a peptide epitope by a MHC class I molecule depends on two parameters: its binding to the MHC molecule and its generation by intracellular Ag processing. In contrast to the former parameter, the mechanisms underlying peptide selection in Ag processing are poorly understood. Peptide translocation by the TAP transporter is required for presentation of most epitopes and may modulate peptide supply to MHC class I molecules. To study the role of human TAP for peptide presentation by individual HLA class I molecules, we generated artificial neural networks capable of predicting the affinity of TAP for random sequence 9-mer peptides. Using neural network-based predictions of TAP affinity, we found that peptides eluted from three different HLA class I molecules had higher TAP affinities than control peptides with equal binding affinities for the same HLA class I molecules, suggesting that human TAP may contribute to epitope selection. In simulated TAP binding experiments with 408 HLA class I binding peptides, HLA class I molecules differed significantly with respect to TAP affinities of their ligands. As a result, some class I molecules, especially HLA-B27, may be particularly efficient in presentation of cytosolic peptides with low concentrations, while most class I molecules may predominantly present abundant cytosolic peptides. 相似文献
53.
54.
Brennemann A.E. Hammer R. Jecusco W.V. III Hollis R.L. 《Robotics & Automation Magazine, IEEE》1995,2(4):30-35
This sensor-based approach for registration and stacking of electronic substrate sublaminates replaces pin-in-slot methods, yet does not require accurate automation equipment. Tests of a pilot workcell for this approach showed that the contact holes were consistently aligned to 2.5 μm (3σ), more than ten times better than the traditional mechanical method 相似文献
55.
BJ Hammer 《Canadian Metallurgical Quarterly》1996,17(6):286-290
VUSN will survive to enter the next millennium as a private university school of nursing only if it is a cutting-edge risk taker that is willing to explore new areas of teaching, practice, and research; otherwise, the expense and support of a private school of nursing cannot be justified. 相似文献
56.
JH Flanagan CV Owens SE Romero E Waddell SH Kahn RP Hammer SA Soper 《Canadian Metallurgical Quarterly》1998,70(13):2676-2684
A series of near-IR fluorescent dyes were prepared which contained an intramolecular heavy atom for altering the fluorescence lifetimes to produce a set of probes appropriate for base-calling in a single-lane DNA sequencing format. The heavy-atom modification consisted of an intramolecular halogen situated on a remote section of the chromophore in order to minimize the perturbation on the lifetimes and fluorescence quantum yields. In addition, the dye series possessed an isothiocyanate functional group to allow facile attachment to sequencing primers. The unconjugated dyes showed similar absorption and emission maxima (lambda abs = 765-768 nm; lambda em = 794-798 nm) as well as fluorescence quantum yields that were invariant, within experimental error, with the heavy atom. However, the lifetimes of these dyes were found to vary with the identity of the halogen substitution (I, tau f = 947 ps; F, tau f = 843 ps, measured in methanol), with an average variation within the dye series of 35 ps. The spectroscopic properties of the free dyes and the dyes conjugated to sequencing primers on the 5'-end of the oligonucleotide were determined in a DNA-sequencing matrix (denaturing gels containing formamide). The results indicated slight differences in the fluorescence properties of the free dyes compared to those of the dye/ primer conjugates in this particular matrix. Inspection of the ground-state absorption spectra showed significant aggregation for the free dyes in this solution, but the conjugated dyes exhibited no sign of aggregation due to the highly anionic nature of the oligonucleotide. The fluorescence lifetimes of the dye/primer conjugates demonstrated lifetimes which ranged from 735 to 889 ps, with an average variation of 51 ps, an adequate difference to allow facile discrimination of these dyes in DNA-sequencing conditions. In addition, the free solution electrophoretic mobilities of the native heavy-atom-modified dyes were found to be very similar. When the dye/primer conjugates were electrophoresed in a cross-linked polyacrylamide gel electrophoresis capillary column, they comigrated, indicating that, in single-lane sequencing applications, when utilizing these dyes, no postrun corrections would be required to correct for dye-dependent mobility shifts. 相似文献
57.
Christoph Wolff Frank Ulrich Briegleb Joerg Bader Klaus Hektor Hans Hammer 《化学工程与技术》1990,13(1):172-184
Many experimental studies reveal that suspended solids considerably alter the coalescence behaviour and hydrodynamic functions of wo-phase flow. But no systematic efforts have yet been undertaken to separate the effects of different particle properties on local gas hold-up, bubble size and interfacial area gas/liquid. The aim of this paper is to present the local values of these parameters in three-phase fluidized beds of different solids, using miniaturized optical fiber and conductivity needle probes. It is shown that particle concentration, size and, in particular, density are decisive for the change in coalescence behaviour. Ranges of normal (?S > ?L) and inverse fluidization (?S < ?L) must be distinguished and the flow regime also exerts a strong influence on the interactions between the dispersed phases, the transition point itself being a function of particle properties can be observed, This effect is evaluated for different column diameters, between 0.1 and 0.3 m. 相似文献
58.
A Hoerauf S Hammer B Müller-Myhsok H Rupprecht 《Canadian Metallurgical Quarterly》1998,26(12):2010-2015
OBJECTIVES: To analyze the frequency of intra-abdominal Candida infection during acute necrotizing pancreatitis and to compare the outcome to patients without Candida infections. DESIGN: Retrospective analysis of data from 37 patients with and without Candida infection. SETTING: Surgical intensive care unit (ICU) in a university hospital. PATIENTS: Thirty-seven patients with acute necrotizing pancreatitis. INTERVENTIONS: Patients were subject to necrosectomy and programmed lavage. MEASUREMENTS AND MAIN RESULTS: Clinical parameters contained in the Acute Physiology and Chronic Health Evaluation (APACHE) II score were monitored, as were microbiological results from the intra-abdominal primary focus and from sites of secondary infections. Body mass index, distribution of underlying diseases, length of ICU stay, number of operations, and outcome were recorded. Multivariate logistic regression analysis for mortality as the dependent variable was performed. Intra-abdominal Candida infection was observed in 13 of 37 cases and was associated with a four-fold greater mortality rate compared with intra-abdominal bacterial infection alone. Multivariate logistic regression analysis demonstrated that Candida infection contributed to mortality significantly (p < .025) and independently from APACHE II (p < .006; mortality odds ratio for the two parameters=12.5). Lack of antimycotic treatment was associated with an increase to 29.2 (p<.001) in the odds ratio. CONCLUSIONS: Given the impact of Candida infection on mortality to acute necrotizing pancreatitis and the apparent benefit from antimycotic chemotherapy, the data argue for an early fungicide chemotherapeutic intervention. 相似文献
59.
Jeffrey P. Freidberg Donald Batchelor Jeffrey Coderre Fred Driscoll Gail Glendinning Charles Greenfield David Hammer Michael Mauel Edward Ott John Sarff Edward Thomas Francois Waelbroeck Harold Weitzner Daniel Winske 《Journal of Fusion Energy》2004,23(4):237-261
This report summarizes the findings and recommendations of the second Committee of Visitors (COV) whose charge was to review the manner in which the U. S. Department of Energy’s Office of Fusion Energy Science (OFES) manages certain programs under its charter. The specific programs reviewed by this COV involve confinement innovation and basic plasma sciences. The charge letter from the Department of Energy is included as Appendix A. 相似文献
60.
MG Johnsen KF Appel PL Madsen FK Vogensen K Hammer J Arnau 《Canadian Metallurgical Quarterly》1996,218(2):306-315
Two major structural proteins, MHP (major head protein) and MTP (major tail protein), from the lactococcal temperate phage TP901-1 were sequenced at their amino acid termini, and derived degenerate oligonucleotides were used to locate the corresponding genes in the phage genome. This genomic region was sequenced. The sequence characterized includes a total of 11 open reading frames (ORFs) showing an operon structure. Upstream of each ORF, except ORF b2 and ORF x, potential ribosome-binding sites were found, suggesting independent translation. However, coupled translation is suggested for ORF x and as a possibility for ORF b3 and ORF c2, which have ribosome-binding sites located more distant from their start codons. ORF b2 may be translationally fused with mhp at a low frequency. The mhp and mtp genes are transcribed as a 3.7-kb mRNA with at least six additional ORFs. The organization of the genomic region analyzed resembles that of other distantly related phages, providing possible roles for the uncharacterized ORFs. 相似文献