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951.
Jürgen Fuhrmann André Fiebach Manfred Uhle Andreas Erdmann Charles R. Szmanda Chi Truong 《Microelectronic Engineering》2009,86(4-6):792-795
Pattern doubling by cross-linking of a spacer triggered by residual acid diffusion from a previously developed primary structure into the spacer is a possible option to create the necessary structure widths for the 32 nm node with current exposure technology by pattern doubling. A particular advantage of this process step would be the self-alignment to the primary structure, which would render a second exposure step unnecessary. In the paper, we present a new prototypical model of the bake step of this process and discuss the dependency of the desired behavior on parameters of the model. 相似文献
952.
César Marconi María José Castillo Mabel Ramini Hernán Svoboda 《Welding International》2013,27(9):618-628
ABSTRACTFillet joints are one of the most commonly used joints in various industries, in particular for agricultural machinery. However, the complexity of the pieces that require welding often makes accessibility difficult for the welder for this kind of joint, and working and displacement angles are important aspects to be evaluated. In addition, in the GMAW process, the use of the Ar-20%CO2 mixture as the shield gas has increased at the expense of 100% CO2, generally requiring an adjustment of the electrical parameters. On the other hand, the incorporation of new materials with higher strength also involves optimizing the welding procedure. The aim of this study was to evaluate the effect of two shield gases (Ar-20% CO2 and 100% CO2), three working angles (30, 45 and 60°) and two displacement angles (45° using the push technique and 60° using the pull technique) on the dimensional characteristics of the seam and the mechanical strength of the fillet joint from a microalloyed steel with high strength welded using GMAW. The highest levels of penetration corresponded to the test specimens welded using the pull technique and with CO2. The over thickness was smaller for conditions with the push technique and the gas mixture. The microhardness of the weld metal, for a similar working angle, was higher for the gas mixture in all cases. Indices of acceptability were developed, which graded geometric aspects and these were compared with the mechanical properties obtained on the welds, showing a good correlation. 相似文献
953.
José A. Larrauri Pilar Rupérez F. Saura-Calixto 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1997,205(1):39-42
Antioxidant compounds associated with some types of dietary fibres may be responsible in part for the beneficial effects
on health of high-dietary-fibre diets. The antioxidant activity of a high-dietary-fibre mango peel product and of some commercial
samples was determined by the ferric thiocyanate colorimetric method. At a concentration of 0.05%, the antioxidant activity
of mango peel dietary fibre was 0.75 times as effective as that of 2-tert-butyl-4-hydroxyanisol (BHA) and 1.4 and 3.4 times higher, respectively, than that of French PARAD’OX (a commercial polyphenols
concentrate) and of DL-α-tocopherol. All Bran, Quaker Oats, lemon and apple fibre did not exhibit any antioxidant capacity. The obtention of high-dietary-fibre
products with bioactive compounds could be useful for the food industry and the antioxidant activity may be a new property
to consider in the quality evaluation of these ingredients.
Received: 25 January 1996 / Revised version: 10 June 1996 相似文献
954.
Maria José Ocio Pablo Salvador Fernandez Miguel Rodrigo Paula Periago A. Martinez 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1997,205(4):325-328
A time temperature integrator (TTI) was developed by immobilizing Bacillus stearothermophilus spores in a cylindrical particle consisting of an alginate-starch-mushroom purée. The particle showed homogeneous spore distribution,
and when heated over a temperature range of 121 – 130° C negligible spore leakage was observed after the thermal process.
The experimental data on spore survivor levels obtained for each temperature-time combination were compared with theoretical
predictions using a mathematical model. The results showed a good correlation between the experimental and theoretical data.
All these results provide evidence that this artificial particle could be a very reliable TTI for monitoring the thermal impact
on micro-organisms during validating sterilization processes in continuous aseptic systems.
Received: 25 February 1997 相似文献
955.
Isothermal mechanical spectrometry experiments were carried out between 10−4 and 100 Hz on strain hardening aluminum samples, after annealings at various temperatures ranging between 300 and 700 K.
For lower annealing temperatures (<480 K), internal friction spectra exhibit only a low frequency background. After annealings
above 480 K, a relaxation peak superimposed to the background stands out. The peak height is, first, increasing for annealing
temperatures below 580 K and then decreasing. The apparent relaxation parameters are found to be strongly dependent on the
annealing temperature. The evolution of the internal friction spectra cannot be correlated with a grain boundary relaxation
but with a reversible motion of dislocation segments inside dislocation networks developed during recovery annealings. 相似文献
956.
Virtual adjustable sources are introduced in equivalent network representation of boundary conditions. For this purpose, integral equations are to be solved simple application of analog Kirchoff’s and Ohm’s laws. These adjustable sources represent generalized trial quantities. In order to illustrate this proposed approach, equivalent network representation of lossy planar transmission lines with arbitrary metallization thickness is presented. 相似文献
957.
Miguel Ángel Rincón‐Cervera María Dolores Suárez‐Medina José Luis Guil‐Guerrero 《European Journal of Lipid Science and Technology》2009,111(9):920-925
Fifteen roes from different marine fish species available in Spain were analyzed in order to determine their fatty acid (FA) composition, especially the eicosapentaenoic acid (20:5n‐3, EPA) and docosahexaenoic acid (22:6n‐3, DHA) contents. Roes from Atlantic bonito (Sarda sarda), European squid (Loligo vulgaris), cuttlefish (Sepia spp.), lumpfish (Cyclopterus lumpus), European hake (Merluccius merluccius), Atlantic salmon (Salmo salar) and gonads of male Atlantic mackerel (Scomber scombrus) reached EPA + DHA amounts higher than 30% of the total FA, and among them, roes from lumpfish, European hake and salmon provide different FA type ratios that could make them adequate as dietary sources of EPA and DHA. 相似文献
958.
BACKGROUND: Skin diseases have only recently been considered as a possible public health problem in developing countries. Data supporting this matter are scarce. The aim of this study is to report the experience of a specialized dermatologic center in Bamako (Mali) in order to complete two previous studies conducted in the Bamako area: a prevalence study in the general population and a study in nonspecialized health centers of Bamako. It is our intention to provide a comprehensive picture of the problem of skin diseases in an African developing country. METHODS: We retrospectively collected all cases of skin diseases diagnosed during consultations provided at the Institut Marchoux in Bamako, the only center specializing in dermatology in Mali, during the year 1993. RESULTS: A total of 10,575 new outpatients were seen with 10,889 skin diseases. The main skin diseases registered were as follows: infectious dermatoses (41% of all diagnoses, including scabies (16.6%), superficial mycoses (13.6%), and primary pyoderma (5.6%)), dermatitis (20.4%), papular urticaria (4.4%), acne (4.2%), pityriasis alba (3.6%), keratoderma (3.6%), and urticaria (3%). Typical tropical infectious diseases accounted for only 1% of all diagnoses. CONCLUSIONS: It appears that certain skin diseases (mainly scabies and pyoderma) are an important health problem for the population of the Bamako area. Public health policies should be implemented in order to manage this problem rationally. 相似文献
959.
José R. Sendra Javier del Pino Antonio Hernández Benito González Javier García Andrés García-Alonso Antonio Nunez 《Analog Integrated Circuits and Signal Processing》2003,35(2-3):121-132
In this work we propose a modification to the conventional lumped equivalent circuit model for integrated inductors. Also the widely used parametric model is modified. The proposed models expand the frequency range where the integrated inductor behavior is accurately predicted. They are useful in developing automatic tools to assist the designers in selecting and automatically laying-out integrated inductors [1]. This work is based on measurements from integrated inductors fabricated in a standard silicon process. 相似文献
960.
This study addresses a novel approach of obtaining gold nanostructures, via directional eutectoid decomposition and selective
etching of Fe-Au alloys. The eutectoid transformation occurs at 2.3%Au, which agrees perfectly with existing DTA and calculated
data. The results are thus experimentally supporting the calculated part of the binary Fe-Au phase diagram. Gold nanofibres
were rectangular in shape, constrained with two perpendicular crystallographic directions, showing the faceted nature of the
Au phase. In addition, it was shown that a range of gold nanostructures, including gold nanoparticles, short nanorods, and
nanofibres might be achieved depending on the processing route. The uniformity and regularity of the obtained nanostructures
are limited, due to a non-cooperative mechanism of the eutectoid transformation. These homomorph gold nanostructures have
the same high potential as other gold nanostructures but also the advantage of being inherently organized in a single crystalline
matrix. 相似文献