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691.
VF 《中国眼镜科技杂志》2014,(7):70-75
正3月1~3日,第44届Mido(米兰国际眼镜展)在意大利米兰Fiera Milano展馆如期举行。本届米兰展依然是6个展馆,但是为了更利于买家参观,组委会将传统的双展馆设计合为一个馆:空气流通性更好,展馆功能性更强,展览场地的利用也更充分。其中,汇聚了世界知名眼镜品牌的 相似文献
692.
Sabine?MüllerEmail author Merlin?Bittlinger Kirsten?Brukamp Markus?Christen Orsolya?Friedrich Malte-C.?Gruber Jon?Leefmann Grischa?Merkel Saskia?K.?Nagel Marco?Stier Ralf?J.?Jox 《Ethik in der Medizin》2018,30(2):91-106
Definition of the problem
Fifteen years after establishing neuroethics as an international academic field, neuroethics has emerged as a vibrant, dynamic area of scientific research.Arguments
Within a short period of a few years, specific conferences, journals, research funding programs, professional societies, and institutes were founded. Nonetheless, considerable disagreement about its definition and subject matter still remain. We argue for a differentiated conceptualization according to which the deliberate reflection of ethical problems arising from the neurosciences and their predominantly neurotechnological application belongs as much to neuroethics as does the ethical reflection of the neuroscience of morality. This does not comprise neuroscientific or neuropsychological research on morality itself, but includes the contemplation of the significance of such research for ethics and the law. Here, we provide an overview about the most important topics in neuroethics and elucidate the relevance of neuroethics for a vast diversity of societal domains reaching well beyond medicine and health care.Conclusion
The great potential of neuroethics as a novel branch of academic research lies in finding new answers to pressing questions of high societal relevance by linking neurophilosophy and bioethics topics as well as its broad interdisciplinary network.693.
The use of plastic containers will grow 11% per year over the next ten years as metal and glass decline. Plastic is the material of choice for food containers in all areas of food processing including hot-fill and retort packaging. This is due in large part to the strides that have been made in barrier property improvement, better manufacturing, and improvements in the economics, esthetics, and physical properties of plastics. Hot-fill and retort packaging account for approximately 64% of the total packaged foods, and in the next 10 years this is expected to increase to 68%. Of the two, the hot-fill method reportedly will gain in importance while retorting will decline by about 1% per year in effect pushing the growth in hot-fill packaging to about twice that of the overall food packaging business. Since 1980, PVC bottles have grown from 100 MM lbs to more than 200 MM lbs of resin in 1987 (growth of approximately 15% per year). However, PVC bottles still represent only 7% of all plastic bottles and only 1% of all materials used to make rigid containers—an indication of great future potential. One of the serious disadvantages of PVC, however, is its low heat resistance which limits the service temperature of finished articles to about 70°C. Further penetration by PVC bottles can be accelerated by raising the heat resistance above the hot-fill levels of 85°C–100°C. This would permit PVC to be used for many food applications such as fruit juices and table syrups. Now an additive is available that can be formulated with PVC to form miscible, transparent blends with increased service temperatures. The miscibility of the glutarimide acrylic copolymers in PVC allows it to significantly improve heat resistance without effecting the optical properties of the container. As a result, single layer PVC bottles can be made on conventional blow molding equipment that can be hot-filled at 85°C–100°C, have glass-like clarity, with good impact and moderate oxygen barrier resistance. The discussion will include guidelines for compounding the imide copolymer with PVC, properties attainable, and a look at the economics versus other hot-fillable containers. 相似文献
694.
Rene Prieler Markus Mayrhofer Markus Eichhorn‐Gruber Günther Schwabegger Christoph Hochenauer 《火与材料》2019,43(1):34-50
In the present two‐parted study, a numerical approach is shown to consider fire resistance tests in virtual space, including the combustion, thermal analysis of the test specimen, and the deformation process. This part is dealing with the combustion process and thermal analysis of different building materials tested in a fire resistance furnace. Instead of using coupled computational fluid dynamics (CFD)/finite element method simulation for the combustion and thermal heat conduction in the solid, which is commonly used in literature, the present approach considers these transport phenomena in one CFD simulation. This method enables a two‐way coupling between the gas phase and the solid material, where chemical reactions and the release of volatile components into the gas phase can occur (eg, release of water vapour from gypsum). To validate the numerical model, a fire resistance test of a steel door, which is a multilayer construction, and a wall made of gypsum blocks were experimentally and numerically investigated. Due to the chemical reactions inside the gypsum, water vapour is released to the gas phase reducing the flue gas temperature about 80 K. This effect was taken into account using a two‐way coupling in the CFD model, which predicted temperatures in close accordance to the measurement. 相似文献
695.
Renaud Grasset-Bourdel Arnaud Alzina Marc Huger Thierry Chotard Robert Emler Dietmar Gruber Harald Harmuth 《Journal of the European Ceramic Society》2013,33(5):913-923
In some industrial applications, the need to improve the thermal shock resistance of refractories by optimisation of their microstructural design is of major importance. Refractories with enhanced thermal shock resistance usually present a rather low resistance to crack initiation but high resistance to crack propagation (rising R-curves), as well as a mechanical behaviour deviating from pure linear elastic fracture mechanics (LEFM), often qualified as nonlinear. The present work aimed at studying the influence of thermal micro-damage within the microstructure released during the cooling process on the nonlinearity of the mechanical behaviour in tension. The two-phase composites considered were magnesia-spinel refractories with different spinel inclusions content allowing to modulate the micro-damage level. Two different destructive mechanical tests, namely tensile and wedge splitting tests, were performed and their results were compared. The influence of thermal damage on different relevant mechanical parameters was investigated, and a quantitative correlation analysis between these parameters was proposed. 相似文献
696.
Dr. Gustav Oberdorfer Dr. Alexandra Binter Dr. Silvia Wallner Dr. Katharina Durchschein Dr. Mélanie Hall Prof. Kurt Faber Prof. Peter Macheroux Prof. Karl Gruber 《Chembiochem : a European journal of chemical biology》2013,14(7):836-845
In recent years, Old Yellow Enzymes (OYEs) and their homologues have found broad application in the efficient asymmetric hydrogenation of activated C?C bonds with high selectivities and yields. Members of this class of enzymes have been found in many different organisms and are rather diverse on the sequence level, with pairwise identities as low as 20 %, but they exhibit significant structural similarities with the adoption of a conserved (αβ)8‐barrel fold. Some OYEs have been shown not only to reduce C?C double bonds, but also to be capable of reducing nitro groups in both saturated and unsaturated substrates. In order to understand this dual activity we determined and analyzed X‐ray crystal structures of NerA from Agrobacterium radiobacter, both in its apo form and in complex with 4‐hydroxybenzaldehyde and with 1‐nitro‐2‐phenylpropene. These structures, together with spectroscopic studies of substrate binding to several OYEs, indicate that nitro‐containing substrates can bind to OYEs in different binding modes, one of which leads to C?C double bond reduction and the other to nitro group reduction. 相似文献
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Fuzzy-trace theory's concepts of identity judgment, nonidentity judgment, and similarity judgment provide a unified account of the false-memory phenomena that have been most commonly studied in children: false-recognition effects and misinformation effects. False-recognition effects (elevated false-alarm rates for unpresented distractors that preserve the meanings of presented targets) are due to increased rates of similarity or false identity judgment about distractors or to decreased rates of nonidentity judgment. Misinformation effects (erroneous acceptance of misleading postevent information and erroneous rejection of actual events) are also due to variability in rates of similarity, identity, and nonidentity judgment. Two experimental paradigms are presented, one for false recognition (conjoint recognition) and one for misinformation (conjoint misinformation), that allow investigators to tease apart the contributions of these processes to children's false-memory reports. Each paradigm is implemented in a mathematical model that provides numerical estimates of the processes. 相似文献