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941.
Large-scale diffusion of distributed energy resources (DERs) will have a profound impact on electricity infrastructure functioning: it will bring radical changes to the traditional model of generation and supply as well as to the business model of the energy industry. DERs comprise distributed power generators, distributed energy storages and controllable loads. There are, however, many uncertainties that influence the design and operation of DERs. This paper clarifies these uncertainties by proposing and applying a comprehensive framework for uncertainty analysis. We thereby adopt an integrated approach that considers not only the technical, but also the economic and institutional uncertainties. A delineation of the work is a focus on residential DERs and on micro-CHP systems specifically. After the proposed framework for uncertainty analysis is explained the uncertainties pertaining to the design and operation of residential DERs and micro-CHP systems are identified. In a case study system a selection of the uncertainties are quantitatively analysed. The case study system consists of a household that intelligently applies a micro-CHP unit in conjunction with energy storages and that interacts with its energy supplier. With a sensitivity analysis of the system model the salient impacts of the uncertainties on system behaviour and performance are enunciated. 相似文献
942.
Nadine Kaiser Dr. Tom Mejuch Roman Fedoryshchak Dr. Petra Janning Prof. Edward W. Tate Prof. Dr. Herbert Waldmann 《Chembiochem : a European journal of chemical biology》2019,20(2):134-139
Protein myristoylation plays key roles in biological processes, for instance, in membrane attachment and activation of proteins and in mediating protein–protein and protein–lipid interactions. Furthermore, myristoylated proteins are involved in disorders, including cancer and viral infections. Therefore, new tools to study protein myristoylation are in high demand. Herein, we report the development of photoactivatable probes, based on a diazirine-substituted analogue of myristic acid. The probes bind to and, upon irradiation, covalently label the lipid-binding chaperone protein uncoordinated 119 (UNC119). UNC119 increases overall solubility and regulates specifically the transport of myristoylated proteins between intercellular membranes. The binding mode of the probes is similar to that of the myristate moiety, and the residues inside the hydrophobic pocket of UNC119 proteins that are critical for covalent binding have been identified. The interaction with UNC119 was also demonstrated in cell lysate by means of affinity enrichment. Moreover, it is shown that the myristate analogue can be incorporated into peptide substrates by N-myristoyl transferases of Leishmania and Trypanosoma protozoan parasites. 相似文献
943.
Bifurcation loads of single and double tapered beams of glued‐laminated timber with intermediate lateral supports. This paper presents bifurcation loads of simply supported tapered beams of glued‐laminated timber with intermediate lateral supports at the upper chord which were determined by means of the finite element method on the basis of simple beam models. Comparative computations show the validity of the simplified approximation method according to DIN 1052 in all cases. Increasing slenderness of the girders and decreasing number at intermediate lateral supports, however, lead to significant differences. 相似文献
944.
945.
946.
Andrew Stamper Sang Chong Kourosh Nafisi Petra Feichtinger WeeTeck Chia David Randall Aneesh Khullar 《集成电路应用》2008,(5):30-32
更细的设计规则、更小的缺陷类型、更多的噪声源和新的工艺整合方案,给原本有效的在线晶片检测方法带来了严峻挑战。通过描绘在线检测到的良率限制缺陷的量值以及它们对在线和最终测试良率的影响程度,往往可以获得良率改进最佳方法。特定良率事件的影响程度通常可以决定良率、集成和制程设计团队的工作优先次序。有效的在线缺陷检测不仅可以监控生产线状况、提高良率,还可以防止在制品(WIP)可能发生的缺陷偏移。 相似文献
947.
In vitro study of biological activities of anthocyanin‐rich berry extracts on porcine intestinal epithelial cells 下载免费PDF全文
948.
Dalibor Vojtěch Pavel Lejček Jaromír Kopeček Katrin Bialasová Petra Guhlová 《Composite Structures》2010
Ti–40Al–5Si and Ti–39Al–5Si–2Nb (in at.%) alloys were studied as prospective high-temperature structural composites consisting of γ-(Ti,Nb)Al + α2-(Ti,Nb)3Al matrix and Ti5Si3 reinforcement. The alloys were prepared by arc melting under helium. Oxidation resistance was studied at 900 °C in air. Thermal stability of alloys was investigated by measuring room temperature hardness and compressive strength after long-term annealing at 900 °C. To prepare oriented composites, directional crystallization at rates of 5–115 mm/h was carried out by the floating zone technique. It was observed that the addition of 2% Nb to the Ti–40Al–5Si alloy does not modify eutectic structure. Niobium is almost uniformly distributed in all present phases. Both alloys show excellent oxidation resistance at 900 °C in air. The Nb-addition causes significant improvement of oxidation resistance due to the doping effect and increase of Al activity in the scales. Room temperature hardness and compressive strength of both as-cast alloys are similar – about 500 HV and 1600 MPa, respectively. Room temperature mechanical properties do not reduce significantly after 300 h annealing at 900 °C, due to a high morphological stability of eutectic silicides. Directionally solidified alloys consist of columnar Ti–Al grains elongated in crystallization direction and silicides. Niobium refines both Ti–Al grains and Ti5Si3 silicides. As a consequence, orientation and elongation of silicides in the Nb-containing alloy are reduced. In the Ti–Al–Si alloy directionally crystallized at 5–115 mm/h, the silicide interparticle spacing λ (in mm) is related to the crystallization rate R (in mm/h) by a following expression: λ1.33·R=0.32. In the Nb-containing alloy, silicide interparticle spacing does not depend on the crystallization rate. 相似文献
949.
Petra J. Kluger Ralf Wyrwa Jürgen Weisser Julia Maierle Miriam Votteler Claudia Rode Matthias Schnabelrauch Heike Walles Katja Schenke-Layland 《Journal of materials science. Materials in medicine》2010,21(9):2665-2671
Electrospinning is a long-known polymer processing technique that has received more interest and attention in recent years
due to its versatility and potential use in the field of biomedical research. The fabrication of three-dimensional (3D) electrospun
matrices for drug delivery and tissue engineering is of particular interest. In the present study, we identified optimal conditions
to generate novel electrospun polymeric scaffolds composed of poly-d/l-lactide and poly-l-lactide in the ratio 50:50. Scanning electron microscopic analyses revealed that the generated poly(d/l-lactide-co-l-lactide) electrospun hybrid microfibers possessed a unique porous high surface area mimicking native extracellular matrix
(ECM). To assess cytocompatibility, we isolated dermal fibroblasts from human skin biopsies. After 5 days of in vitro culture,
the fibroblasts adhered, migrated and proliferated on the newly created 3D scaffolds. Our data demonstrate the applicability
of electrospun poly(d/l-lactide-co-l-lactide) scaffolds to serve as substrates for regenerative medicine applications with special focus on skin tissue engineering. 相似文献
950.
Cobo S Molnár G Carcenac F Szilágyi PA Salmon L Vieu C Bousseksou A 《Journal of nanoscience and nanotechnology》2010,10(8):5042-5050
We present a new approach for patterning thin films of Prussian blue at the micro- and nano-metric scales. In a first step, a resist was deposited on a gold surface and patterns were generated by photolithography or electron beam lithography. The Prussian blue with idealized formula of KFe(III)[Fe(II)(CN)6] was deposited through the sequential exposure of the patterned surface to a series of solutions containing alternately absorbable Fe3+ cations and [Fe(CN)6]4- anions. These building blocks are gradually associated into dense and continuous films and patterned structures of Prussian blue can be obtained finally by lift-off. This approach was also used to deposit Prussian blue thin films on interdigitated nanoelectrodes and the current-voltage characteristics of this device were investigated. 相似文献