AbstractPhysical vapor deposited (PVD) coatings are widely-used in tool and component applications, where the predominant aims are the enhancement of the lifetime and an improvement of the economic efficiency. The achievement of these aims amongst others strongly depends on a homogeneous distribution of the coating properties with respect to the entire functional surface, in particular on complex-shaped tools. In order to obtain a sufficient coating homogeneity, pulsed high power plasma processes such as the high power pulsed magnetron sputtering (HPPMS) or the pulsed cathodic arc evaporation (PCAE) has to be chosen. In order to characterize the influence of both technologies on the coating homogeneity, the Debye sheath thickness sDat the substrate side was determined, which is expected to strongly correlate with the coating homogeneity on complex surfaces, since it is a measure for the shielding of charged coating atoms. Measurements with varying pulse parameters were performed. In addition, as reference a direct current magnetron sputtering (dcMS) and cathodic arc evaporation (CAE) process were conducted, respectively. As it is widely used as protective coating for tools in many applications, the coating system (Cr,Al)N was chosen. In the first step, the Debye sheath thickness was determined by means of Langmuir probe. A Debye sheath thickness from sD=430μm to sD=48μm was found for the different processes and parameters. In the second step, the (Cr,Al)N coatings were deposited with selected process parameters on structured tungsten carbide substrates. The coating morphology, coating thickne
(WO2016193548) A process for producing a nanofibrillar cellulose hydrogel comprises obtaining bleached cellulose pulp fibers and providing an aqueous suspension thereof; and subjecting the cellulose pulp fibers in the aqueous suspension to at least 2 cycles of high pressure mechanical disintegration to obtain a nanofibrillar cellulose hydrogel and thereby reducing the number of viable microorganisms present in the suspension by a factor of at least 102; wherein all steps of the process after obtaining the bleached cellulose pulp fibers are performed under conditions of ISO 8 of ISO 14644-1 cleanroom standards or stricter. A nanofibrillar cellulose hydrogel, a system for producing the same and the use of a disintegrating apparatus are also disclosed.
Knapp, Madison R.;Wu, Weiming;Lloyd, Shannon E.;Orellana, Matthew D.;Zhang, Zhongliang
来源期刊：Tetrahedron letters: The International Journal for the Rapid Publication of Preliminary Communications in Organic Chemistry
年/卷/期：2018 / 59 / 25
When simple beta-amino esters were treated with cyanate ion, dihydrouracils were formed. However, the presence of the alpha-carboxylate group in aspartic ester substrates hinders the formation of the pyrimidine ring. Instead, treatment of aspartic esters with carbonate bases yields N-substituted beta-Flactam-4-carboxylates in excellent yields, representing a green, convenient, and efficient synthesis of these biologically interesting molecules. (C) 2018 Elsevier Ltd. All rights reserved.
E. CIAPESSONI;D. CIRIO;A. PITTO;G. GIANNUZZI;M. MARZINOTTO;R. ZAOTTINI;G. GARZI;T. MURAO
会议集名/来源：CIGRE Session 2018: August 26-31, 2018, Paris, France
Power system restoration following large blackouts critically relies on the activation of black start units and/or the availability of restoration paths from alive neighbouring networks. Moreover, operating constraints on voltage and frequency are more difficult to meet than in normal conditions, due to the weakness of the grid and the lack of control resources. The speed and reliability of the process depend on the resources that are involved, the number of manoeuvres needed, and the performances of the control systems. Redundancy of solutions and resources enhances the probability of an efficient restoration. The present paper intends to illustrate the potential benefits of a VSC-HVDC system in the restoration of the Sardinian power system in a 2020 scenario. The power system of Sardinia island is a relatively small one, connected to the continental European system via two HVDC links, one of which has a third terminal in Corsica island. Connection to Corsica is also assured by an AC line. In particular, the paper envisages the upgrade of the existing SACOI (Sardinia-Corsica-Italy) HVDC link by adopting VSC technology, and it compares a conventional restoration scenario of Sardinia against scenarios where the VSC-based SACOI supports the restoration process, acting either as a black start unit or as a reactive power support device (STATCOM). The VSC allows to achieve advantages such as greater flexibility in the restoration process and stable control of the operating quantities. The work herein reported has been carried out in the context of Demo 3 of the Best Paths EU research project.
High Voltage Direct Current;Restoration;Voltage Source Converter