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1.
Makrina A. Chairopoulou Fabian Kratzer Roland Gross Michael Herrmann Ulrich Teipel 《化学工程与技术》2020,43(5):904-912
Thermogravimetric analysis of a coccolith-containing biogenic broth showed a three-step degradation process. According to this system behavior, the biogenic broth was heated to specific temperatures and characterized in terms of its morphology, surface chemistry, and crystallinity. The elemental and organic composition of the treated samples was also evaluated and compared to the reference material. The presented results were acquired in an effort to exploit pretreatment scenarios for such a biogenic system that would improve and support a separation process. 相似文献
2.
M. Striegler B. Matthey U. Mühle A. Michaelis M. Herrmann 《Ceramics International》2018,44(9):10111-10118
Silicon carbide ceramics have found widespread use due to their high corrosion stability. Both solid state-sintered silicon carbide, which has an extremely high corrosion resistance, and silicon-infiltrated silicon carbide are used for various applications. The latter material contains SiC as well as free silicon, which is less stable. Hence, in the present work, the corrosion behavior of silicon-infiltrated silicon carbide ceramics was investigated in NaOH solutions. Long-term corrosion experiments were conducted, and a method for analyzing the corrosion behavior in short-term experiments was developed. The short-term method is based on the accurate measurement of the corrosion depth by laser scanning microscopy on polished surfaces. The results of both methods were in good agreement. The advantage of the short-term method is that it provides information on changes in corrosion mechanisms and corrosion rates in the initial period and as a function of the impurities present. Preferential corrosion of Si at the interface to SiC was observed. TEM investigations revealed that this enhanced corrosion was caused by the segregation of impurities. 相似文献
3.
Chao Ma Anke Malessa Arnold J. Boersma Kai Liu Andreas Herrmann 《Advanced materials (Deerfield Beach, Fla.)》2020,32(20):1905309
Electrostatic interactions play a vital role in nature. Biomacromolecules such as proteins are orchestrated by electrostatics, among other intermolecular forces, to assemble and organize biochemistry. Natural proteins with a high net charge exist in a folded state or are unstructured and can be an inspiration for scientists to artificially supercharge other protein entities. Recent findings show that supercharging proteins allows for control of their properties such as temperature resistance and catalytic activity. One elegant method to transfer the favorable properties of supercharged proteins to other proteins is the fabrication of fusions. Genetically engineered, supercharged unstructured polypeptides (SUPs) are just one promising fusion tool. SUPs can also be complexed with artificial entities to yield thermotropic and lyotropic liquid crystals and liquids. These architectures represent novel bulk materials that are sensitive to external stimuli. Interestingly, SUPs undergo fluid–fluid phase separation to form coacervates. These coacervates can even be directly generated in living cells or can be combined with dissipative fiber assemblies that induce life-like features. Supercharged proteins and SUPs are developed into exciting classes of materials. Their synthesis, structures, and properties are summarized. Moreover, potential applications are highlighted and challenges are discussed. 相似文献
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Lissy Z. F. Gross Mariana Sacerdoti Prof. Albrecht Piiper Prof. Stefan Zeuzem Dr. Alejandro E. Leroux Dr. Ricardo M. Biondi 《ChemMedChem》2020,15(18):1682-1690
Angiotensin converting enzyme 2 (ACE2) is the human receptor that interacts with the spike protein of coronaviruses, including the one that produced the 2020 coronavirus pandemic (COVID-19). Thus, ACE2 is a potential target for drugs that disrupt the interaction of human cells with SARS-CoV-2 to abolish infection. There is also interest in drugs that inhibit or activate ACE2, that is, for cardiovascular disorders or colitis. Compounds binding at alternative sites could allosterically affect the interaction with the spike protein. Herein, we review biochemical, chemical biology, and structural information on ACE2, including the recent cryoEM structures of full-length ACE2. We conclude that ACE2 is very dynamic and that allosteric drugs could be developed to target ACE2. At the time of the 2020 pandemic, we suggest that available ACE2 inhibitors or activators in advanced development should be tested for their ability to allosterically displace the interaction between ACE2 and the spike protein. 相似文献
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Higher Hydrocarbon Production through Oxidative Coupling of Methane Combined with Hydrogenation of Carbon Oxides 下载免费PDF全文
In the production of higher hydrocarbons, combining oxidative coupling of methane (OCM) with hydrogenation of the formed carbon oxides in a separate reactor provides an alternative to the currently applied methane conversion to syngas followed by Fischer‐Tropsch synthesis. The effects of CH4:O2 feed ratio in the OCM reactor and partial pressures of H2 or/and H2O in the hydrogenation reactor were analyzed to maximize production of C2+ hydrocarbons and reduce COx formation. The highest C2+ yield was achieved with low CH4:O2 feed ratio for OCM and removal of the formed water before entering the hydrogenation reactor. 相似文献
9.
Anna Skrzyska Anna Albrecht ukasz Albrecht 《Advanced Synthesis \u0026amp; Catalysis》2016,358(17):2838-2844
A novel approach for the stereoselective synthesis of benzothiophene derivatives with a fused dihydropyran moiety is demonstrated. The reaction of 2‐alkylidenebenzothiophene‐3(2H)‐ones with dienamines derived from α,β‐unsaturated aldehydes and chiral secondary amines proceeds according to the inverse‐electron‐demand hetero‐Diels–Alder pathway. The formation of the aromatic benzothiophene moiety is a driving force for the developed reaction cascade. Target products bearing three adjacent stereogenic centers are obtained in excellent yields and in a highly stereoselective manner.
10.
Binding Mode and Structure–Activity Relationships around Direct Inhibitors of the Nrf2–Keap1 Complex 下载免费PDF全文
Dr. Eric Jnoff Dr. Claudia Albrecht Dr. John J. Barker Dr. Oliver Barker Dr. Edward Beaumont Dr. Steven Bromidge Dr. Frederick Brookfield Dr. Mark Brooks Dr. Christian Bubert Dr. Tom Ceska Vincent Corden Dr. Graham Dawson Dr. Stephanie Duclos Dr. Tara Fryatt Dr. Christophe Genicot Dr. Emilie Jigorel Dr. Jason Kwong Rosemary Maghames Innocent Mushi Dr. Richard Pike Dr. Zara A. Sands Dr. Myron A. Smith Dr. Christopher C. Stimson Dr. Jean‐Philippe Courade 《ChemMedChem》2014,9(4):699-705
An X‐ray crystal structure of Kelch‐like ECH‐associated protein (Keap1) co‐crystallised with (1S,2R)‐2‐[(1S)‐1‐[(1,3‐dioxo‐2,3‐dihydro‐1H‐isoindol‐2‐yl)methyl]‐1,2,3,4‐tetrahydroisoquinolin‐2‐carbonyl]cyclohexane‐1‐carboxylic acid (compound (S,R,S)‐ 1 a ) was obtained. This X‐ray crystal structure provides breakthrough experimental evidence for the true binding mode of the hit compound (S,R,S)‐ 1 a , as the ligand orientation was found to differ from that of the initial docking model, which was available at the start of the project. Crystallographic elucidation of this binding mode helped to focus and drive the drug design process more effectively and efficiently. 相似文献