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101.
Andreas Zehnsdorf Norman Stock Juliane Richter Michael Blumberg Roland A. Müller 《化学,工程师,技术》2016,88(8):1138-1144
There is increasing interest worldwide in the decentralized treatment of gray water. Since ground‐level areas are generally costly, gray‐water treatment can also be carried out using helophyte mats on the roofs of buildings as an alternative. Alongside the water treatment itself, this process also has a positive effect on the indoor climate in the building. In a test carried out under realistic conditions, it was shown that a helophyte mat with a root‐layer depth of 0.1 m and with hydraulic loads per unit up to 15 L m?2d?1 is suitable for treating typical gray water from a residential building. 相似文献
102.
Identification and Structure–Activity Relationship Studies of Small‐Molecule Inhibitors of the Methyllysine Reader Protein Spindlin1
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Dr. Dina Robaa Dr. Tobias Wagner Chiara Luise Dr. Luca Carlino Joel McMillan Dr. Ralf Flaig Prof. Dr. Roland Schüle Prof. Dr. Manfred Jung Prof. Dr. Wolfgang Sippl 《ChemMedChem》2016,11(20):2327-2338
The methyllysine reader protein Spindlin1 has been implicated in the tumorigenesis of several types of cancer and may be an attractive novel therapeutic target. Small‐molecule inhibitors of Spindlin1 should be valuable as chemical probes as well as potential new therapeutics. We applied an iterative virtual screening campaign, encompassing structure‐ and ligand‐based approaches, to identify potential Spindlin1 inhibitors from databases of commercially available compounds. Our in silico studies coupled with in vitro testing were successful in identifying novel Spindlin1 inhibitors. Several 4‐aminoquinazoline and quinazolinethione derivatives were among the active hit compounds, which indicated that these scaffolds represent promising lead structures for the development of Spindlin1 inhibitors. Subsequent lead optimization studies were hence carried out, and numerous derivatives of both lead scaffolds were synthesized. This resulted in the discovery of novel inhibitors of Spindlin1 and helped explore the structure–activity relationships of these inhibitor series. 相似文献
103.
4‐Biphenylalanine‐ and 3‐Phenyltyrosine‐Derived Hydroxamic Acids as Inhibitors of the JumonjiC‐Domain‐Containing Histone Demethylase KDM4A
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Dr. Ludovica Morera Dr. Martin Roatsch Michael C. D. Fürst Dr. Inga Hoffmann Dr. Johanna Senger Mirjam Hau Dr. Henriette Franz Prof. Dr. Roland Schüle Prof. Dr. Markus R. Heinrich Prof. Dr. Manfred Jung 《ChemMedChem》2016,11(18):2063-2083
Overexpression of the histone lysine demethylase KDM4A, which regulates H3K9 and H3K36 methylation states, has been related to the pathology of several human cancers. We found that a previously reported hydroxamate‐based histone deacetylase (HDAC) inhibitor (SW55) was also able to weakly inhibit this demethylase with an IC50 value of 25.4 μm . Herein we report the synthesis and biochemical evaluations, with two orthogonal in vitro assays, of a series of derivatives of this lead structure. With extensive chemical modifications on the lead structure, also by exploiting the versatility of the radical arylation with aryldiazonium salts, we were able to increase the potency of the derivatives against KDM4A to the low‐micromolar range and, more importantly, to obtain demethylase selectivity with respect to HDACs. Cell‐permeable derivatives clearly showed a demethylase‐inhibition‐dependent antiproliferative effect against HL‐60 human promyelocytic leukemia cells. 相似文献
104.
Wolfram Witte Daniel Abou‐Ras Karsten Albe Gottfried H. Bauer Frank Bertram Christian Boit Rudolf Brüggemann Jürgen Christen Jens Dietrich Axel Eicke Dimitrios Hariskos Matthias Maiberg Roland Mainz Max Meessen Mathias Müller Oliver Neumann Thomas Orgis Stefan Paetel Johan Pohl Humberto Rodriguez‐Alvarez Roland Scheer Hans‐Werner Schock Thomas Unold Alfons Weber Michael Powalla 《Progress in Photovoltaics: Research and Applications》2015,23(6):717-733
The gallium gradient in Cu(In,Ga)Se2 (CIGS) layers, which forms during the two industrially relevant deposition routes, the sequential and co‐evaporation processes, plays a key role in the device performance of CIGS thin‐film modules. In this contribution, we present a comprehensive study on the formation, nature, and consequences of gallium gradients in CIGS solar cells. The formation of gallium gradients is analyzed in real time during a rapid selenization process by in situ X‐ray measurements. In addition, the gallium grading of a CIGS layer grown with an in‐line co‐evaporation process is analyzed by means of depth profiling with mass spectrometry. This gallium gradient of a real solar cell served as input data for device simulations. Depth‐dependent occurrence of lateral inhomogeneities on the µm scale in CIGS deposited by the co‐evaporation process was investigated by highly spatially resolved luminescence measurements on etched CIGS samples, which revealed a dependence of the optical bandgap, the quasi‐Fermi level splitting, transition levels, and the vertical gallium gradient. Transmission electron microscopy analyses of CIGS cross‐sections point to a difference in gallium content in the near surface region of neighboring grains. Migration barriers for a copper‐vacancy‐mediated indium and gallium diffusion in CuInSe2 and CuGaSe2 were calculated using density functional theory. The migration barrier for the InCu antisite in CuGaSe2 is significantly lower compared with the GaCu antisite in CuInSe2, which is in accordance with the experimentally observed Ga gradients in CIGS layers grown by co‐evaporation and selenization processes. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
105.
Roland Mainz Alfons Weber Humberto Rodriguez‐Alvarez Sergiu Levcenko Manuela Klaus Paul Pistor Reiner Klenk Hans‐Werner Schock 《Progress in Photovoltaics: Research and Applications》2015,23(9):1131-1143
Ga segregation at the backside of Cu(In,Ga)Se2 solar cell absorbers is a commonly observed phenomenon for a large variety of sequential fabrication processes. Here, we investigate the correlation between Se incorporation, phase formation and Ga segregation during fast selenisation of Cu–In–Ga precursor films in elemental selenium vapour. Se incorporation and phase formation are analysed by real‐time synchrotron‐based X‐ray diffraction and fluorescence analysis. Correlations between phase formation and depth distributions are gained by interrupting the process at several points and by subsequent ex situ cross‐sectional electron microscopy and Raman spectroscopy. The presented results reveal that the main share of Se incorporation takes place within a few seconds during formation of In–Se at the top part of the film, accompanied by outdiffusion of In out of a ternary Cu–In–Ga phase. Surprisingly, CuInSe2 starts to form at the surface on top of the In–Se layer, leading to an intermediate double graded Cu depth distribution. The remaining Ga‐rich metal phase at the back is finally selenised by indiffusion of Se. On the basis of a proposed growth model, we discuss possible strategies and limitations for the avoidance of Ga segregation during fast selenisation of metallic precursors. Solar cells made from samples selenised with a total annealing time of 6.5 min reached conversion efficiencies of up to 14.2 % (total area, without anti‐reflective coating). The evolution of the Cu(In,Ga)Se2 diffraction signals reveals that the minimum process time for high‐quality Cu(In,Ga)Se2 absorbers is limited by cation ordering rather than Se incorporation. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
106.
Chemikalienfreie Bekämpfung von Holzschädlingen durch dielektrische Erwärmung mit Radiowellen und Mikrowellen
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Christian Hoyer Christian Pfütze Dr. Rudy Plarre Dr. Ulf Trommler Steffen Steinbach Kerstin Klutzny Dr. Frank Holzer Carsten Rabe Björn Höhlig Prof. Frank‐Dieter Kopinke Prof. Detlef Schmidt Dr. Ulf Roland 《化学,工程师,技术》2014,86(8):1187-1197
Thermal pest control requires long treatment times due to the low thermal conductivity of wood and may lead to the formation of cracks. Here, the thermal treatment with radio waves as well as microwaves has been studied. The direct dielectric heating has the advantage of a good homogeneity. The obtained temperature profiles for radio waves were more homogeneous compared to microwaves. Detailed studies showed that elimination of pests was not related to the application of the electromagnetic field itself, but due to the temperature increase. 相似文献
107.
Roland Vogel Regine Boldt Marijan Vučak Liane Häußler 《Polymer Engineering and Science》2014,54(9):2057-2063
It has been reported in the technical literature that whiskers of rodlike single crystals can be used in order to generate shish‐kebab structures or other different lamellae morphologies during isothermal or dynamic crystallization of sheared or presheared polymer melts. The expected advantage of the changed crystalline structure is a reinforcing effect of the composite. A lot of papers reported about the application of inorganic and organic whiskers such as cellulose and chitin whiskers. This study reports on an attempt to use acicular PCC as appropriate whisker for improving mechanical properties of polypropylene. In this article special attention is given to demonstrate the effect of flow induced crystallization under varying shear conditions in order to improve the mechanical properties. The effects were demonstrated using rheology, thermal analysis, tensile testing, and transmission electron microscopy. POLYM. ENG. SCI., 54:2057–2063, 2014. © 2013 Society of Plastics Engineers 相似文献
108.
Sub-micronic, spherical Y2O3:Yb/Er particles comprising clustered nano-units (70 nm) were prepared via ultrasonic spray pyrolysis from pure nitrate precursor solutions with different Yb/Er dopant ratios. The particles were additionally thermally treated at 1100 °C for 12, 24 and 48 h. The structural and morphological characteristics of particles were studied by X-ray powder diffraction, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, energy dispersive X-ray analysis and specific surface area (BET) and were further correlated with their advanced optical properties. For the recorded up-conversion emissions, originating from the following Er3+ transitions: [2H9/2→4I15/2] in blue (407–420 nm); [2H11/2, 4S3/2→4I15/2] green: 510–590 nm; and [4F9/2→4I15/2] in red (640–720 nm) spectral region, the corresponding lifetimes were acquired in the wide temperature range (10–300 K). The most intense green up-conversion emission with the long decay of 550 ms is recorded for Y1.97Yb0.02Er0.01O3 particles thermally treated at 1100 °C for 24 h. 相似文献
109.
Horst Hennig Klaus Ritter Roland Billing 《Advanced Synthesis \u0026amp; Catalysis》1996,338(1):604-613
Photocatalytic Hydrogen Formation from Thioles in the Presence of Vitamin-B12 Model Complexes with Azide as Photochemical Sacrificial Ligand The photolysis of [N3Co(chelat)B] complexes ( 1–3 ) (chelat = dimethylglyoxime, dmg; N,N′-o-phynylenebis(salicylidenimine), salphen; N,N′-ethylene-bis(salicylidenimine), salen; B = pyridine) leads by homolytic cleavage of the Co–N3 bond to both coordinatively unsaturated cobalt(II) chelates [Co(chelat)B] and N3 ligand radicals that undergo fast decay to dinitrogen. The photolysis of the cobalt (III) complexes 1–3 in the presence of thiophenole and other thioles proceeds catalytically and yields the corresponding disulphides and dihydrogen. The mechanism of this photocatalytic generation of dihydrogen is due to the catalytic activity of the coordinatively unsaturated cobalt(II) species formed photochemically. A photocatalytic cycle is proposed describing the generation of hydrogen. Possible photochemical and thermal steps of that cycle are discussed. 相似文献
110.