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971.
    
Lactose solutions of up to 50% (w/v) were incubated with lactases and glucose isomerases for subsequent implementation in dairy product samples to enhance sweetness. A degree of hydrolysis of >90% and of isomerisation of 50% were attainable. The sensory sweetening power of lactose in solutions of up to 50% (w/v) can be enhanced 2–3 times. Based on sensory experiments, application of this bi‐enzymatic system in yoghurt and pudding samples allowed for a 10–20% (w/w) reduction in the total sugar content, whilst retaining equal sweetness. The growth of yoghurt starter cultures was not affected, yet furosine formation more than doubled in high heated, enzyme‐modified milk.  相似文献   
972.
Übersicht Um die Betriebssicherheit großer supraleitender Magnetsysteme für die Kernfusionsforschung zu gewährleisten, muß die im Magnetsystem gespeicherte Energie schnell entladen werden können. Durch die veränderlichen großvolumigen Magnetfelder werden in benachbarten leitfähigen Strukturen durch Induktion hohe Wirbelströme hervorgerufen. Durch sie treten dort elektromagnetische Kräfte. auf, die einzelne Komponenten mechanisch überlasten können. Zur Berechnung dieser Kräfte wurde eine einfache numerischanalytische Methode entwickelt, die im folgenden vorgestellt und mit Finite-Elemente-Verfahren verglichen wird.
Calculation of eddy current densities and forces around large superconducting coils for nuclear fusion
Contents The reliable operation of the superconducting magnet systems used for the magnetic confinement in nuclear fusion research requires the ability of a fast discharge of the stored magnetic energy. The corresponding magnetic field variation gives rise to high eddy currents by inductive coupling with surrounding conductive components. The eddy current forces can lead to a mechanical overload of some of these components. A simple numerical-analytical method was developed in order to calculate these forces. This method is presented and compared with the Finite Element Method.
  相似文献   
973.
Contents The influence of the inertial constants of the asynchronous motors on the statical stability of a complex electrical power system in dependance on the change of its reactance and voltage in the knot points is studied.To keep the stability, the so named inertial-discharge in the system is introduced.
Übersicht Der Einfluß der Trägheitskonstanten der Asynchronmotoren auf die statische Stabilität eines komplizierten Energiesystems je nach den Änderungen seiner Reaktanzen und Spannungen in den Knotenpunkten wird untersucht.Dabei wird der Begriff Trägheitsentladung eingeführt.
  相似文献   
974.
Übersicht Zur Planaritatsanalyse und Planarisierung nichtebener verallgemeinerter Graphen werden programmierbare Algorithmen angegeben. Die Planarisierung erfolgt durch zwei Operatoren für Inzidenztransformationen, die in jeder Technologie einen bestimmten Begriffsinhalt haben.
Contents Programable algorithms for planarity analysis and planarization of generalized graphs are given. The planarization is carried out by means of two operators for incidence transformations. These operators have a certain significance in each technology.

Verzeichnis der verwendeten Symbole A Trägermenge - a Element der Trägermenge - F Fenster - G Graph - Schaltungsgraph - G * Hamiltongraph - G 2 Binärgraph - J Jordan-Masche - K Kontur eines Fensters - R Relation - r Element der Relation - Erweiterung, Neg– - Äquipotential-Erweiterung, Neg– - Reduktion, Neg – - Planarisierung  相似文献   
975.
Übersicht Das System der—auch dynamisch gültigen—Spannungsgleichungen und der Drehmomentgleichung des Käfigläufermotors wird unter Berücksichtigung der Oberfelder aufgestellt, und es werden alle für die Berechnung erforderlichen Induktivitäten ermittelt. Durch zwei lineare Transformationen läßt sich das Gleichungssystem weitgehend vereinfachen. Hierdurch wird es möglich, das Verhalten der Maschine einschließlich aller Kopplungen der Felder und der eventuell auftretenden Unipolarflüsse zu beschreiben, ohne daß hierfür jeweils besondere physikalische Betrachtungen erforderlich wären. Ein einfaches Beispiel, in dem für die Drehmomentberechnung nur das Grundfeld und die dritte Harmonische berücksichtigt werden, erläutert die Anwendung des Gleichungssystems.
Contents The system of the voltage equations and the torque equation of the squirrel cage motor—including the dynamical behaviour—are set up considering the space harmonic fields. The necessary inductances for the analysis of the machine are determined. By the use of two linear transformations the system of equations can be extensively simplified. By this means the behaviour of the machine including all harmonic field linkages and the homopolar fluxes which may occur can be described without the necessity of particular physical considerations. A simple example, in which are taken into account in the torque calculation only the fundamental and the third harmonic fields, illustrates the application of the system of equations.
  相似文献   
976.
    
One-third of all proteins are estimated to require metals for structural stability and/or catalytic activity. Desthiobiotin probes containing metal binding groups can be used to capture metalloproteins with exposed active-site metals under mild conditions so as to prevent changes in metallation state. The proof-of-concept was demonstrated with carbonic anhydrase (CA), an open active site, Zn2+-containing protein. CA was targeted by using sulfonamide derivatives. Linkers of various lengths and structures were screened to determine the optimal structure for capture of the native protein. The optimized probes could selectively pull down CA from red blood cell lysate and other protein mixtures. Pull-down of differently metallated CAs was also investigated.  相似文献   
977.
    
The innate immune system's interaction with bacterial cells plays a pivotal role in a variety of human diseases. Carbohydrate units derived from a component of bacterial cell wall, peptidoglycan (PG), are known to stimulate an immune response. Nonetheless, access to modified late-stage peptidoglycan intermediates is limited due to their synthetic complexity. A method to rapidly functionalize PG fragments is needed to better understand the natural host–PG interactions. Here methyl N,O-hydroxylamine linkers are incorporated onto a synthetic PG derivative, muramyl dipeptide (MDP). The modification of MDP maintained the ability to stimulate a nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) immune response dependent on the expression of nucleotide-binding oligomerization domain-containing protein 2 (Nod2). Intrigued by this modification's maintenance of biological activity, several applications were explored. Methyl N,O-hydroxylamine MDP was amendable to N-hydroxylsuccinimide (NHS) chemistry for bioconjugation to fluorophores as well as a self-assembled monolayer for Nod2 surface plasmon resonance analysis. Finally, linker incorporation was applicable to larger PG fragments, both enzymatically generated from Escherichia coli or chemically synthesized. This methodology provides rapid access to PG probes in one step and allows for the installation of a variety of chemical handles to advance the molecular understanding of PG and the innate immune system.  相似文献   
978.
979.
980.
We present a single-chip asynchronous multiprocessor optoelectronic bit-sliced arrayed (AMOEBA) crossbar switch. The AMOEBA switch addresses the challenge to produce a large-scale, nonblocking packet switch through dense integration of photonic devices directly onto silicon VLSI circuits. Optoelectronic-VLSI technology is used to integrate the switch fabric, routing controller, packet buffers, line interface circuits, and optoelectronic conversion devices on a single chip. We show how free-space optical interconnects and wavelength-and-space-division-multiplex networking on single-mode fibers can provide switched interconnection between multiple nodes in a distributed computing environment. An optomechanical transceiver package accomplishes the free-space-to-fiber interfacing. We report the implementation and testing of the key components of a 16-channel AMOEBA prototype switch with a potential capacity of 12.8 Gb/s (or 800 Mb/s/channel), and capable of switching 16 million packets per second  相似文献   
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