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Dr. Chi Chung Lee Dr. Nathaniel S. Sickerman Prof. Dr. Yilin Hu Prof. Dr. Markus W. Ribbe 《Chembiochem : a European journal of chemical biology》2016,17(6):453-455
A recent electrochemical investigation suggests that the mononuclear molybdenum enzyme YdeY utilizes redox‐active ligands during catalysis. 相似文献
994.
To analyze the challenge of large-scale integration of renewables during the next decades, we present a conceptual power system model that bridges the gap between long term investment allocation and short-term system operation decisions. It integrates dynamic investments in generation, transmission and storage capacities as well as short-term variability and spatial distribution of supply and demand in a single intertemporal optimization framework. Large-scale grid topology, power flow distributions and storage requirements are determined endogenously. Results obtained with a three region model application indicate that adequate and timely investments in transmission and storage capacities are of great importance. Delaying these investments, which are less costly than investments in generation capacities, leads to system-wide indirect effects, such as non-optimal siting of renewable generation capacities, decreasing generation shares of renewables, increasing residual emissions and hence higher overall costs. 相似文献
995.
Thorsten N. Klauke Thomas M.A. Gronewold Markus Perpeet Susanne Plattes Brigitte Petersen 《Meat science》2013
Aim of the study was the application of biosensor technique to measure the concentration of an acute phase protein (APP) within complex matrices from animal origin. For the first time, acute phase protein haptoglobin (Hp) was detected from unpurified meat juice of slaughter pigs by a label-free biosensor-system, the SAW-based sam®5 system. The system uses a sensor chip with specific antibodies to catch Hp while the mass-related phase shift is measured. The concentration is calculated as a function of these measured phase shifts. The results correlate very well with reference measurement results obtained by enzyme-linked immunosorbent assay (ELISA), R = 0.98. The robust setup of the surface acoustic wave (SAW)-based system and its ability to measure within very short time periods qualifies it for large-scale analyses and is apt to identify rapidly pigs in the meat production process whose consumption would have an increased risk for consumers. 相似文献
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997.
In a sample of 7,695 families in the prospective, nationally representative British Millennium Cohort Study, this study examined whether characteristics of the 1st-born child predicted parents' timing and probability of having another child within 5 years after the 1st child's birth. Infant temperament was assessed with the Carey Infant Temperament Scale (Carey, 1972; Carey & McDevitt, 1978) at age 9 months, childhood socioemotional and behavioral characteristics with the Strengths and Difficulties Questionnaire (Goodman, 2001), and childhood cognitive ability with the Bracken School Readiness Assessment (Bracken, 2002) test at age 3 years. Survival analysis modeling indicated that the 1st child's low reactivity to novelty in infancy, high prosociality, low conduct problems, and high cognitive ability in childhood were associated with increased probability of parents having another child. Except for reactivity to novelty, these associations became stronger with time. High emotional symptoms were also positively associated with childbearing, but this was likely to reflect reverse causality—that is, the effect of sibling birth on the 1st child's adjustment. The results suggest that child effects, particularly those related to the child's cognitive ability, adaptability to novelty, and prosocial behavior, may be relevant to parents' future childbearing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Amirsaman Farrokhpanah Markus Bussmann Javad Mostaghimi 《Numerical Heat Transfer, Part B: Fundamentals》2017,71(4):299-312
When modeling the phase change, the latent heat released (absorbed) during solidification (melting) must be included in the heat transfer equation. In this paper, different smoothed particle hydrodynamics (SPH) methods for the implementation of latent heat, in the context of transient heat conduction, are derived and tested. First, SPH discretizations of two finite element methods are presented, but these prove to be computationally expensive. Then, by starting from a simple approximation and enhancing accuracy using different numerical treatments, a new SPH method is introduced, that is fast and easy to implement. An evaluation of this new method on various analytical and numerical results confirms its accuracy and robustness. 相似文献
999.
Vipin Agarwal Tim B. van Erp Luigi Balzano Markus Gahleitner Matthew Parkinson Leon E. Govaert Victor Litvinov Arno P.M. Kentgens 《Polymer》2014
A better understanding of structure-property relations is necessary to design novel materials. In this study, we investigate the morphology and chemical structure of five commercial grades of propylene-based polymers in relation to the change in yield- stress as a function of strain-rate. Substantial emphasis has been laid on understanding the chain microstructure in the relation to chain dynamics in the amorphous phase. Heterogeneous Ziegler–Natta catalysis was used to prepare the samples with differing ratios of propylene and ethylene units. Various analytical techniques such as WAXS, SAXS, solution- and solid-state NMR were employed to characterize their structure. The results indicate a reduction in crystallinity, melting temperature, long-period and crystal thickness with increasing ethylene content. Solid-state NMR data reveal the presence of four components in these samples, which is an extension of the traditional three phase model found in most semi-crystalline polymers. The additional fourth phase is attributed to a rubber-like component that is primarily composed of chain segments rich in ethylene units and shows an increase in chain dynamics with increasing ethylene content in the samples. Mechanical experiments show that yield stress decreases with increase in the amount ethylene which can be correlated to the observed increase in chain dynamics in the amorphous phase. 相似文献
1000.
The relation between composition and mechanical performance of a series of binary polyolefin blends was studied in this article. A fractionation of these model compounds with temperature rising elution fractionation (TREF) was applied to study the possibility to fractionate industrially relevant heterophasic polyolefin systems. The separation quality according to molecular structures or chemical composition was found to be good for most of the systems, but especially the separation of ethylene‐propylene random copolymer and high density polyethylene by TREF turned out to be difficult if not impossible. An extensive mechanical characterisation including the determination of brittle‐to‐ductile transition curves showed significant effects of modifier type and amount. Toughness effects can be related primarily to the modulus differences between modifier and matrix. Compatibility and particle size only have a secondary influence, but must be considered for a detailed interpretation of the mechanics of the investigated systems. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献