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71.
Thirteen aromatic carboxylic acids in Finnish tall oil fatty acids were identified and quantified by gas chromatography-mass spectrostereoisomeric secodehydroabeitic acids secoditerpene and dehydroabeitic acids. The other aromatic acids were various secoditerpene ando- alkyl- phenylalkanoic acids. A number of minor nonaromatic acids with mono- and bicyclic, and branched chain structures were also identified and quantified.  相似文献   
72.
We measured the static magnetization of polycrystalline CuGeO3, which exhibits the spineierls transition around 14.0 K in the absence of the magnetic field. The field dependence of the magnetization below 14.0 K shows a characteristic nonlinear process associated with a phase transition, and phase boundaries between the dimerized phases and other phases were obtained. The magnetic phase diagram qualitatively agrees with that of an organic spin-Peierls material. The phase transition is of first order below 10.0 K, and of second order above 10.0 K. Above 10.0 K, the critical field decreases from 13 to 0 T with increasing temperature. On the other hand, it is nearly independent of temperature below 10.0 K.  相似文献   
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We evaluated the long-term angiographic outcome of balloon angioplasty by comparing original and follow-up target coronary narrowing. Rather than using restenosis to determine outcome, as in most angioplasty studies, we took an unusual approach and analyzed outcome in terms that are commonly used in progression and regression studies after medical interventions. Quantitative angiographic measurements were undertaken in 315 narrowings with an initial diameter stenosis <90% before and after angioplasty and at follow-up. Angiographic deterioration (>10% increase in follow-up diameter stenosis) was identified in 44 (14%) narrowings. Angiographic deterioration was not influenced by age, sex, risk factors, lipid profile, or the indication for angioplasty. Deterioration was also not predicted by the severity, length, or the location of the narrowing. The deteriorating narrowings had a higher recoil after dilatation compared with narrowings with angiographic improvement (21% +/- 31% vs 12% +/- 17%, p = 0.006); the residual stenosis after angioplasty was therefore higher. The late loss was also significantly increased compared with narrowings with angiographic improvement (65% +/- 26% vs 8% +/- 24%, p < 0.001). We conclude that the incidence of angiographic deterioration of coronary disease as a result of restenosis is uncommon but not negligible. Interventional cardiologists should resist the temptation to dilate mild, silent coronary narrowings because the procedure might have an unfavorable angiographic (and probably clinical) effect.  相似文献   
76.
There are many tests available for examining the quality of frying oils. Since judgements can be quite different depending on the test used and the recommendations given the results are compared here and the best tests for examining the quality of frying oils are identified.  相似文献   
77.
New production and work practices set new proficiency requirements for employees in operative organisations. Most of these requirements involve information and communication. We can train and educate people to meet with these challenges and design their physical and information environments to support and facilitate them in their work. New information tools play a central role in this development. But what kind of tools? How to apply these tools to enhance employees’ learning by reflection. In this article we will discuss the emergency of shop-floor information environment from the sociotechnical point of view. In addition, the possibilities and limitations of electronic performance support as a solution are evaluated. Shop-floor information artifacts are tools used to produce, organise, store and distribute work related information in a shop-floor environment. They may be very simple like handwritten notes or user interfaces to extremely complex data management systems.  相似文献   
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In industries manufacturing metallic molds, various NC machine tools are used. We have already proposed a desktop NC machine tool with compliance control capability to automatically cope with the finishing process of LED lens molds. The NC machine tool has the ability to control the polishing force acting between an abrasive tool and a work piece. The force control method is called impedance model force control. The most effective gain is the desired damping of the impedance model. Ideally, the desired damping is calculated from the critical damping condition after considering the effective stiffness in the force control system. However, there is a problem in that the effective stiffness of the NC machine tool has undesirable nonlinearity. The nonlinearity has a bad influence on the force control stability. In this article, a fine tuning method of the desired damping is considered using neural networks. The neural networks acquire the nonlinearity of effective stiffness. The promise is evaluated through an experiment.  相似文献   
80.
Hase F  Höpfner M 《Applied optics》1999,38(15):3129-3133
A new method for the determination of ray paths as well as resulting path segments and partial gas columns within a layered atmosphere is presented. Any singularity at the tangent point is avoided. No use is made of the gross spherical symmetry of the Earth's atmosphere. Using this approach we examine the impact of the Earth's oblate shape and horizontal atmospheric inhomogeneities on infrared limb spectra.  相似文献   
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