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排序方式: 共有177条查询结果,搜索用时 347 毫秒
1.
Ferdinand P. Ferragu O. Lechien J.L. Lescop B. Magne S. Marty V. Rougeault S. Kotrotsios G. Neuman V. Depeursinge Y. Michel J.B. Van Uffelen M. Varelas D. Berthou H. Pierre G. Renouf C. Jarret B. Verbandt Y. Stevens W. Voet M.R.H. Toscano D. 《Lightwave Technology, Journal of》1995,13(7):1303-1313
Recent developments of stability control in mines, essentially based on Ge-doped fiber Bragg gratings (FBG) are reported including results about the different aspects of the system: accurate characterizations of FBG, sensor network topology and multiplexing method, user interface design and sensor packaging 相似文献
2.
Frank C. Magne James A. Harris Robert A. Pittman Evald L. Skau 《Journal of the American Oil Chemists' Society》1966,43(9):519-524
The stepwise HBr titration method for the cyclopropenoid analysis of cottonseed oils is subject to serious inaccuracies when
applied to samples containing higher cyclopropenoid concentrations, particularly if they contain appreciable amounts of alumina-adsorbable
materials. A modification of the method is described which eliminates these sources of error. Its validity has been established
by the analysis of a wide range of synthetic compositions including compositions containing massive amounts of interfering
HBr-reactive substances and other alumina-adsorbable materials. The method with further modification can be used to analyze
glycerides with the same high degree of accuracy.
Presented at the AOCS Meeting in Houston, April 1965.
So. Utiliz. Res. Dev. Div., ARS, USDA. 相似文献
3.
Robert R. Mod Frank C. Magne Evald L. Skau 《Journal of the American Oil Chemists' Society》1959,36(12):616-619
Summary Eighty-eight amine salts of long-chain fatty acids have been prepared, purified by solvent crystallization, and characterized.
Forty-five of these were salts of palmitic acid. The rest included salts of capric, lauric, myristic, stearic, oleic, elaidic,
and 12-hydroxystearic acids. A variety of aliphatic, aromatic, and heterocyclic amines, including primary, secondary, and
tertiary amines, were investigated. The majority of these gave 1∶1 acid-amine compounds on solvent recrystallization of an
equimolar mixture of acid and amine. Some of the amines gave no crystallizable salt, and with others the pure salt could not
be obtained by this procedure. Under the same conditions the symmetrical alkyl, substituted alkyl, and aralkyl secondary amines
investigated gave crystallizable compounds containg two molecules of fatty acid to one of amine. Molecular compounds of 2-aminopyridine
with four molecules of saturated fatty acid were formed by recrystallization starting with a 1 to 4 amine-acid mixture. Surface-tension
measurements were made for aqueous solutions of a few of the amine salts.
One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S.
Department of Agriculture. 相似文献
4.
Frank C. Magne Robert R. Mod Evald L. Skau 《Journal of the American Oil Chemists' Society》1961,38(6):294-296
A systematic investigation has been made of the effect of fatty acid composition on the compatibility of the corresponding
mixed morpholides as plasticizers for vinyl chloride-vinyl acetate copolymer resins. Plasticizer evaluation data were obtained
for the morpholides of lauric, palmitic, elaidic, and epoxyoleic acids and compared with the literature values for other fatty
acid morpholides and morpholide mixtures.
Ternary compatibility-composition diagrams have been constructured for the oleic-linoleic-stearic and the oleic-linoleic-palmitic
morpholide systems. These diagrams make it possible to predict what adjustment, if any, must be made in the composition of
any mixture of these fatty acids so that the corresponding morpholide mixture will be compatible. The diagrams will be useful
in selecting the most appropriate and economical fatty acid sources from which to make compatible morpholide mixtures.
Presented at the 52nd Annual Meeting, American Oil Chemists’ Society, St. Louis, Mo., May 1–3, 1961.
One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U.S.
Department of Agriculture. 相似文献
5.
6.
This study investigated the effect of moving from small offices to a landscape environment for 19 Visual Display Unit (VDU) operators at Alcatel Denmark AS. The operators reported significantly improved lighting condition and glare situation. Further, visual discomfort was also significantly reduced on a Visual Analogue Scale (VAS). There was no significant correlation between lighting condition and visual discomfort neither in the small offices nor in the office landscape. However, visual discomfort correlated significantly with glare in small offices i.e. more glare is related to more visual discomfort. This correlation disappeared after the lighting system in the office landscape had been improved. There was also a significant correlation between glare and itching of the eyes as well as blurred vision in the small offices, i.e. more glare more visual symptoms. Experience of pain was found to reduce the subjective assessment of work capacity during VDU tasks. There was a significant correlation between visual discomfort and reduced work capacity in small offices and in the office landscape. When moving from the small offices to the office landscape, there was a significant reduction in headache as well as back pain. No significant changes in pain intensity in the neck, shoulder, forearm, and wrist/hand were observed.The pain levels in different body areas were significantly correlated with subjective assessment of reduced work capacity in small offices and in the office landscape.By careful design and construction of an office landscape with regard to lighting and visual conditions, transfer from small offices may be acceptable from a visual-ergonomic point of view. 相似文献
7.
Mekonnen SM Olufsen M Smalås AO Brandsdal BO 《Journal of molecular graphics & modelling》2006,25(2):176-185
The role of the primary binding residue (P1) in complexes between three different subtilases (subtilisin Carlsberg, thermitase and proteinase K) and their canonical protein inhibitor eglin c have been studied by free energy calculations. Based on the crystal structures of eglin c in complex with subtilisin Carlsberg and thermitase, and a homology model of the eglin c-proteinase K complex, a total of 57 mutants have been constructed and docked into their host proteins. The binding free energy was then calculated using molecular dynamics (MD) simulations combined with the linear interaction energy (LIE) method for all complexes differing only in the nature of the amino acid at the P1 position. LIE calculations for 19 different complexes for each subtilase were thus carried out excluding proline. The effects of substitutions at the P1 position on the binding free energies are found to be very large, and positively charged residues (Arg, Lys and His) are particularly deleterious for all three enzymes. The charged variants of the acidic side chains are found to bind more favorably as compared to their protonated states in all three subtilases. Furthermore, hydrophobic amino acids are accommodated most favorably at the S1-site in all three enzymes. Comparison of the three series of binding free energies shows only minor differences in the 19 computed relative binding free energies among these subtilases. This is further reflected in the correlation coefficient between the 23 relative binding free energies obtained, including the possible protonation states of ionizable side chains, but excluding the P1 Pro, for subtilisin Carlsberg versus thermitase (0.95), subtilisin versus proteinase K (0.94) and thermitase versus proteinase K (0.96). 相似文献
8.
Magne Jørgensen Author Vitae 《Journal of Systems and Software》2010,83(6):1039-1050
We currently know little about the factors that motivate the selection and change of strategy in judgment-based effort estimation. A better understanding of these issues may lead to more accurate judgment-based effort estimates and motivates the four experiments reported in this paper. The experiments’ two main results are the identification of the importance of “estimation surprises” (large estimation errors) to motivate estimation strategy change and the large individual variation in the initial choice of estimation strategy. The individual variation seems not only to be a result of differences in previous experiences, but also a result of differences in the mental “accessibility” of the strategies. We found, for example, that the use of a type of strategy was increased when we instructed a developer to use the same type of strategy on unrelated tasks immediately before. 相似文献
9.
We present a manufacturing method based on the dynamic use of phase plates to photowrite Bragg gratings. This process allows for control of the local value of the index modulation envelope in the grating. The application to apodized fiber Bragg gratings is discussed. 相似文献
10.
As the demand for empirical evidence for claims of improvements in software development and evolution has increased, the use of empirical methods such as case studies has grown. In case study methodology various types of triangulation is a commonly recommended technique for increasing validity. This study investigates a multiple data source case study with the objective of identifying whether more findings, trustworthier findings and other findings are made using multiple data source triangulation, than had a single data source been used. The case study investigated analyses key lead-time success factors for a software evolution project in a large organization developing eBusiness systems with high-availability high throughput transaction characteristics. By tracing each finding in that study to the individual evidences motivating the finding, it is suggested that a multiple data source explorative case study can have a higher validity than a single data source study. It is concluded that a careful case study design with multiple sources of evidence can result in not only better justified findings than a single data source study, but also other findings. Thus this study provides empirically derived evidence that a multiple data source case study is more trustworthy than a comparable single data source case study. 相似文献