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排序方式: 共有4476条查询结果,搜索用时 15 毫秒
91.
Alex Frano Eva Benckiser Yi Lu Meng Wu Miguel Castro‐Colin Manfred Reehuis Alexander V. Boris Eric Detemple Wilfried Sigle Peter van Aken Georg Cristiani Gennady Logvenov Hanns‐Ulrich Habermeier Peter Wochner Bernhard Keimer Vladimir Hinkov 《Advanced materials (Deerfield Beach, Fla.)》2014,26(2):258-262
92.
Veronika Kaufmann Siegfrid Scherer Ulrich Kulozik 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2010,5(42):59-64
Die ESL-Technologie stellt nach der H-Milch eine weitere Entwicklung mit hohem Zusatznutzen in Bezug auf Haltbarkeit und Vorratshaltung
dar, wovon sowohl Handel als auch Verbraucher gleicherma?en profitieren k?nnen. Im Vergleich zum herk?mmlich pasteurisierten
Produkt bringt das ESL-Konzept entscheidende Vorteile hinsichtlich der Haltbarkeit der Milch mit sich, wirkt sich dabei aber
kaum oder nur geringfügig auf die für den Verbraucher entscheidenden bzw. wertrelevanten Produkteigenschaften aus. ESL-Produkte
sind in diesem Sinne also nicht nur „l?nger haltbar”, sondern unserer Einsch?tzung nach auch „l?nger frisch”. Dass gerade
die Produktcharakteristika der ESL-Milch den Wünschen der Verbraucher entgegenkommen, zeigt sich an der stetig steigenden
Nachfrage nach diesen Produkten und dem damit einhergehenden Absatzrückgang von herk?mmlich pasteurisierter Frischmilch. Die
Verbraucher haben also durch ihr Kaufverhalten in den letzten Jahren bereits deutlich gemacht, dass sie der ESL-Milch durchaus
positiv gegenüberstehen und sich mit diesem Produktkonzept keineswegs „get?uscht” fühlen, was die hier zusammengefassten Fakten
eindeutig untermauern. 相似文献
93.
The calculation of the heat release rate by oxygen consumption in a controlled‐atmosphere cone calorimeter 下载免费PDF全文
The standard cone calorimeter according to ASTM E 1354 and ISO 5660 enables reaction‐to‐fire tests to be performed in ambient atmospheric conditions. A controlled‐atmosphere chamber modifies the standard apparatus in a way that allows tests to be performed in nonambient conditions as well. The enclosed chamber is placed underneath the standard exhaust hood and does not have a closed connection to the hood. With this open arrangement, the exhaust gases are diluted by excess air drawn in from the laboratory surroundings. Heat‐induced changes in the consequential dilution ratio affect the calculation of fire quantities and, when neglected, lead to deviations of up to 30% in heat release rate. The paper introduces a test protocol and equations to calculate the heat release rate taking dilution effects into account. A mathematical correction is shown that compensates for the dilution effects while avoiding extensive mechanical changes in the equipment. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
94.
95.
Rachel Mika Dorin William A. Phillip Hiroaki Sai Jörg Werner Menachem Elimelech Ulrich Wiesner 《Polymer》2014
Using a combination of block copolymer self-assembly and non-solvent induced phase separation, isoporous ultrafiltration membranes were fabricated from four poly(isoprene-b-styrene-b-4-vinylpyridine) triblock terpolymers with similar block volume fractions but varying in total molar mass from 43 kg/mol to 115 kg/mol to systematically study the effect of polymer size on membrane structure. Small-angle X-ray scattering was used to probe terpolymer solution structure in the dope. All four triblocks displayed solution scattering patterns consistent with a body-centered cubic morphology. After membrane formation, structures were characterized using a combination of scanning electron microscopy and filtration performance tests. Membrane pore densities that ranged from 4.53 × 1014 to 1.48 × 1015 pores/m2 were observed, which are the highest pore densities yet reported for membranes using self-assembly and non-solvent induced phase separation. Hydraulic permeabilities ranging from 24 to 850 L m−2 h−1 bar−1 and pore diameters ranging from 7 to 36 nm were determined from permeation and rejection experiments. Both the hydraulic permeability and pore size increased with increasing molar mass of the parent terpolymer. The combination of polymer characterization and membrane transport tests described here demonstrates the ability to rationally design macromolecular structures to target specific performance characteristics in block copolymer derived ultrafiltration membranes. 相似文献
96.
Patrick J. Riss Dr. Fabian Debus Dr. René Hummerich Ulrich Schmidt Dr. Patrick Schloss Dr. Hartmut Lueddens Dr. Frank Roesch Dr. 《ChemMedChem》2009,4(9):1480-1487
N‐4‐Fluorobut‐2‐yn‐1‐yl‐2β‐carbomethoxy‐3β‐phenyltropane (PR04.MZ) has been developed as dopamine transporter (DAT) ligand for molecular imaging. It contains a terminally fluorinated, conformationally constrained nitrogen substituent that is well suited for the introduction of fluorine‐18. The present report describes the pharmacological characterisation of [18F]PR04.MZ. The ligand shows an IC50 value of 2 nM against human DAT, whereas the IC50 value against human serotonin transporter and human noradrenalin transporter are lower (110 nM and 22 nM , respectively). Furthermore, its ex vivo organ distribution, its binding profile in the rat brain and reversibility of binding were examined. A μPET study illuminates a fast kinetic profile and specific binding to rat DAT. 相似文献
97.
98.
Challenges and Progress in High‐Throughput Screening of Polymer Mechanical Properties by Indentation
Johannes M. Kranenburg Catherine A. Tweedie Krystyn J. van Vliet Ulrich S. Schubert 《Advanced materials (Deerfield Beach, Fla.)》2009,21(35):3551-3561
Depth‐sensing or instrumented indentation is an experimental characterization approach well‐suited for high‐throughput investigation of mechanical properties of polymeric materials. This is due to both the precision of force and displacement, and to the small material volumes required for quantitative analysis. Recently, considerable progress in the throughput (number of distinct material samples analyzed per unit time) of indentation experiments has been achieved, particularly for studies of elastic properties. Future challenges include improving the agreement between various macroscopic properties (elastic modulus, creep compliance, loss tangent, onset of nonlinear elasticity, energy dissipation, etc.) and their counterpart properties obtained by indentation. Sample preparation constitutes a major factor for both the accuracy of the results and the speed and efficiency of experimental throughput. It is important to appreciate how this processing step may influence the mechanical properties, in particular the onset of nonlinear elastic or plastic deformation, and how the processing may affect the agreement between the indentation results and their macroscopic analogues. 相似文献
99.
Farida Benmouna Ulrich Maschke Xavier Coqueret Mustapha Benmouna 《Polymer International》2001,50(4):469-474
The phase behaviour of binary nematogen mixtures of side‐chain liquid crystal crosslinked polymers and low molecular weight liquid crystals is investigated with particular emphasis on the effects of nematic coupling. The cross nematic quadrupole parameter ν12 is assumed to be proportional to the geometric average of ν11 and ν22 characteristic of single nematogens. In the weak coupling limit, the proportionality constant is lower than 1, and the phase diagram exhibits a reduced miscibility of the nematogens. In the case of strong coupling, the proportionality constant exceeds 1 resulting in higher miscibility. This is characterized by a nematic order that extends to temperatures above the upper nematic–isotropic transition temperature. A wide region of miscibility emerges showing a single nematic phase. Nematogens having similar nematic–isotropic transition temperatures exhibit different phase properties from systems with widely separated transition temperatures. Effects of the polymer volume fraction at crosslinking, rubber elasticity parameters of the network, and the Flory–Huggins interaction parameter on the equilibrium phase diagram of these systems are discussed. © 2001 Society of Chemical Industry 相似文献
100.
This paper considers the inverse 1-center location problem with edge length augmentation on a tree network T with n + 1 vertices. The goal is to increase the edge lengths at minimum total cost subject to given modification bounds such that
a predetermined vertex s becomes an absolute 1-center under the new edge lengths. Using a set of suitably extended AVL-search trees we develop a combinatorial algorithm
which solves the inverse 1-center location problem with edge length augmentation in O(n log n) time. Moreover, it is shown that the problem can be solved in O(n) time if all the cost coefficients are equal. 相似文献