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81.
Mingchao Wang Huanhuan Shi Panpan Zhang Zhongquan Liao Mao Wang Haixia Zhong Friedrich Schwotzer Ali Shaygan Nia Ehrenfried Zschech Shengqiang Zhou Stefan Kaskel Renhao Dong Xinliang Feng 《Advanced functional materials》2020,30(30)
2D conjugated metal‐organic frameworks (2D c‐MOFs) are emerging as a novel class of conductive redox‐active materials for electrochemical energy storage. However, developing 2D c‐MOFs as flexible thin‐film electrodes have been largely limited, due to the lack of capability of solution‐processing and integration into nanodevices arising from the rigid powder samples by solvothermal synthesis. Here, the synthesis of phthalocyanine‐based 2D c‐MOF (Ni2[CuPc(NH)8]) nanosheets through ball milling mechanical exfoliation method are reported. The nanosheets feature with average lateral size of ≈160 nm and mean thickness of ≈7 nm (≈10 layers), and exhibit high crystallinity and chemical stability as well as a p‐type semiconducting behavior with mobility of ≈1.5 cm2 V?1 s?1 at room temperature. Benefiting from the ultrathin feature, the nanosheets allow high utilization of active sites and facile solution‐processability. Thus, micro‐supercapacitor (MSC) devices are fabricated mixing Ni2[CuPc(NH)8] nanosheets with exfoliated graphene, which display outstanding cycling stability and a high areal capacitance up to 18.9 mF cm?2; the performance surpasses most of the reported conducting polymers‐based and 2D materials‐based MSCs. 相似文献
82.
ao.Univ.-Prof. DI Dr. Friedrich Schöberl DI Bernhard Zeiringer Mag. Christian Moritz 《?sterreichische Wasser- und Abfallwirtschaft》2014,66(5-6):190-205
The EU Water Framework Directive commits member states to achieve good ecological status in all waterbodies. Artificial or heavily modified waterbodies must reach at least its good ecological potential. In view of these requirements, simple and feasible methods are required in order to evaluate habitat suitability for relevant target species in larger river reaches. Well-developed models for determining the relationship between stream flows and habitat for target species mainly based on micro- and meso-scale already exist. However, the application of such models is complex and time-consuming and consequently limited to relatively short river segments. The objective of this study is to develop a simplified applicable assessment model to evaluate habitat conditions for selected target fish. This model uses hydro-morphological indicators for the habitat assessment and relies on correlative relations between habitat suitability and hydro-morphological features of river stretches (average Froude-number, relative flow width, mean bed slope, relative water depth and flow velocity). The indicators were determined as reach-related averages, derived from 2D model simulations (hydraulic and habitat-specific). Particular emphasis was laid on using a wide range of river stretches with different hydro-morphological characteristics (hydrology, bed substratum, bed structures, degree of braiding, sinuosity of the river course, mean bed width and bed slope). As a result, a set of model equations enables the evaluation of fish habitat conditions in river stretches as a function of flow and morphology. The habitat suitability assessment focuses on four preselected target species: brown trout, European grayling and for low slope rivers common nase and barbel. 相似文献
83.
Elke Rauscher-Gabernig Roland Grossgut Friedrich Bauer Peter Paulsen 《Food Control》2009,20(4):423-429
Although alimentary intake of histamine can cause intoxication, legal limits for histamine content in the EU, exist for certain seafish species only. The present study suggests tolerable levels for fermented sausage, fish and cheese which are based on relating the amount of histamine not expected to cause any health effects after ingestion to typically consumed amounts of food. Limits of 500 and 400 mg/kg would seem to be justifiable for fermented sausage and cheese, respectively. For fish species other than those already regulated in EU, the “m”/”M” limits of 100 and 200 mg/kg can be adopted. These limits can be met by current food technology. 相似文献
84.
Manel Rodríguez Ripoll Franz Heindl Christoph Lechner Vladimir Totolin Martin Jech Friedrich Bleicher 《摩擦学汇刊》2017,60(3):479-789
Machine hammer peening is a surface treatment technique originally developed for smoothening tools and mold surfaces. Treated surfaces are locally cold-worked, which results in a hardness increase and the induction of compressive residual stresses. In the present work, the feasibility of using this technique as a tool for embedding tungsten carbide hard particles on engineering-relevant substrate materials is systematically investigated. Tungsten carbide particles of three different sizes were embedded onto selected substrates using machine hammer peening. The particle embedment quality of the engineered surfaces was evaluated and correlated to the substrates' mechanical properties. The resulting tribological performance was investigated under reciprocating sliding conditions and the dominant wear mechanisms were correlated with the diameter of the embedded particles. The results show that machine hammer peening is a suitable technique for embedding hard particles in substrates of various materials, which additionally results in an enhancement in wear resistance, thus opening up a wide range of potential applications in tribologically loaded surfaces. 相似文献
85.
Friedrich L. Bauer 《Informatik-Spektrum》2011,34(5):514-518
Vor über 40 Jahren starb am 10. November 1970 viel zu früh der Schweizer Informatik-Pionier Heinz Rutishauser, der an der ETH Zürich forschte und lehrte. F.L. Bauer erinnert sich an seinen Kollegen. 相似文献
86.
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89.
Dr. Saskia Wolf Dr. Svenja Warnecke Jörg Ehrit Dr. Friedrich Freiberger Prof. Dr. Rita Gerardy‐Schahn Prof. Dr. Chris Meier 《Chembiochem : a European journal of chemical biology》2012,13(17):2605-2615
The cycloSal approach has been used in the past for the synthesis of a range of phosphorylated bioconjugates. In those reports, cycloSal nucleotides were allowed to react with different phosphate nucleophiles. With glycopyranosyl phosphates as nucleophiles, diphosphate‐linked sugar nucleotides were formed. Here, cycloSal‐nucleotides were used to prepare monophosphate‐linked sugar nucleotides successfully in high anomeric purity and high chemical yield. The method was successfully used for the synthesis of three nucleotide glycopyranoses as model compounds. The method was then applied to the syntheses of CMP‐N‐acetyl‐neuraminic acids (CMP‐Neu5NAc) and of four derivatives with different modifications at their amino functions (N‐propanoyl, N‐butanoyl, N‐pentanoyl and N‐cyclopropylcarbonyl). The compounds were used for initial enzymatic studies with a bacterial polysialyltransferase (polyST). Surprisingly, the enzyme showed marked differences in terms of utilisation of the four derivatives. The N‐propanoyl, N‐butanoyl, and N‐pentanoyl derivatives were efficiently used in a first transfer with a fluorescently labelled trisialo‐acceptor. However, elongation of the resulting tetrasialo‐acceptors worsened progressively with the size of the N‐acyl chain. The N‐pentanoyl derivative allowed a single transfer, leading to a capped tetramer. The N‐cyclopropylcarbonyl derivative was not transferred. 相似文献
90.