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排序方式: 共有985条查询结果,搜索用时 31 毫秒
1.
Application of Polyimide-based Microfluidic Devices on Acid-catalyzed Hydrolysis of Dimethoxypropane
Microfluidic devices intensify transport phenomena and can improve chemical processes. New manufacturing processes and materials are perpetually developed due to constantly growing interest in process intensification. In this contribution, the authors present the design and application of polyimide-foil-based microfluidic mixing devices manufactured by reactive ion etching. As appropriate model reaction system, acid-catalyzed 2,2-dimethoxypropane (DMP) hydrolysis was chosen and investigated in three different mixing structure with varying flow rate. Energy dissipation rates were calculated to estimate mixing performances. The results show good mixing quality for Reynolds numbers between 10 and 100 and similar mixing times scales for all investigated microstructured mixers. 相似文献
2.
Dr. Anders Højgaard Hansen Henriette B. Christensen Dr. Sunil K. Pandey Dr. Eugenia Sergeev Alice Valentini Julia Dunlop Domonkos Dedeo Simone Fratta Dr. Brian D. Hudson Prof. Graeme Milligan Prof. Trond Ulven Prof. Elisabeth Rexen Ulven 《ChemMedChem》2021,16(21):3326-3341
Free fatty acid receptor 2 (FFA2) is a sensor for short-chain fatty acids that has been identified as an interesting potential drug target for treatment of metabolic and inflammatory diseases. Although several ligand series are known for the receptor, there is still a need for improved compounds. One of the most potent and frequently used antagonists is the amide-substituted phenylbutanoic acid known as CATPB ( 1 ). We here report the structure-activity relationship exploration of this compound, leading to the identification of homologues with increased potency. The preferred compound 37 (TUG-1958) was found, besides improved potency, to have high solubility and favorable pharmacokinetic properties. 相似文献
3.
Nicolas Larché Benoit Emo Audrey Allion Elisabeth Johansson Dominique Thierry 《工业材料与腐蚀》2021,72(8):1338-1349
With lower alloying cost and higher mechanical properties, lean duplex stainless steels can be an alternative to the more commonly used austenitic stainless steels. However, these alloys are still not the preferred choice, probably due to a lack of field experience. A study was thus initiated in view of defining the limits of use of selected (lean) duplexes for urban wastewater treatment units. The present paper shows the localized corrosion performance of selected lean duplexes in chloride contaminated solutions. The results are compared with austenitic S30403 and S31603 and with the more standard duplexes S82441 and S32205. The effect of welding was also investigated. Exposures in field municipal wastewater plants were conducted for 1 year in low and high chloride content units. The results show that lean duplexes S32101 and S32202 can be used as alternatives to S30403 and S31603 in low chloride electrolytes. At 500 ppm of chloride content, duplex stainless steel S32304 showed better corrosion resistance than S30403 and S31603. For higher chloride contents (1000 ppm and above) the standard duplexes S82441 and S32205 shall be preferred. 相似文献
4.
Elisabeth Wyart Laure B. Bindels Erica Mina Alessio Menga Serena Stanga Paolo E. Porporato 《International journal of molecular sciences》2020,21(22)
Cachexia is a complication of dismal prognosis, which often represents the last step of several chronic diseases. For this reason, the comprehension of the molecular drivers of such a condition is crucial for the development of management approaches. Importantly, cachexia is a syndrome affecting various organs, which often results in systemic complications. To date, the majority of the research on cachexia has been focused on skeletal muscle, muscle atrophy being a pivotal cause of weight loss and the major feature associated with the steep reduction in quality of life. Nevertheless, defining the impact of cachexia on other organs is essential to properly comprehend the complexity of such a condition and potentially develop novel therapeutic approaches. 相似文献
5.
Svenja Dittrich Elisabeth Reitz Karl Günter Schell Ethel Claudia Bucharsky Michael J. Hoffmann 《International Journal of Applied Ceramic Technology》2020,17(3):1304-1313
Glass ceramics are supposed to produce stable sealants between ceramic electrolyte and ferritic steel in planar SOFC stacks. The screen printing method is a suitable industrial process in order to produce layers with tailored height and width reproducibly. An appropriate suspension was developed for this application and improved by adjusting the additive composition. This study investigates the rheological behavior of screen printing inks and the corresponding topography of the printed layers. Rotary measurements were carried out to analyse the impact of shear rates on viscosity showing shear thinning behavior. In addition, oscillatory rheometry is performed to gain information about the viscoelastic properties of the slurries and to understand the internal structure of the developed inks. The viscoelasticity and the recovery behavior after shear loading are crucial for the topography of printed films. The principal investigations are executed on solvent-based suspensions, whereby the knowledge gained is used for a transfer to water-based systems allowing a more environmentally friendly handling. 相似文献
6.
Kazuo Tsubota Stephen C. Pflugfelder Zuguo Liu Christophe Baudouin Hyo Myung Kim Elisabeth M. Messmer Friedrich Kruse Lingyi Liang Jimena Tatiana Carreno-Galeano Maurizio Rolando Norihiko Yokoi Shigeru Kinoshita Reza Dana 《International journal of molecular sciences》2020,21(23)
Over the past decades, the number of patients with dry eye disease (DED) has increased dramatically. The incidence of DED is higher in Asia than in Europe and North America, suggesting the involvement of cultural or racial factors in DED etiology. Although many definitions of DED have been used, discrepancies exist between the various definitions of dry eye disease (DED) used across the globe. This article presents a clinical consensus on the definition of DED, as formulated in four meetings with global DED experts. The proposed new definition is as follows: “Dry eye is a multifactorial disease characterized by a persistently unstable and/or deficient tear film (TF) causing discomfort and/or visual impairment, accompanied by variable degrees of ocular surface epitheliopathy, inflammation and neurosensory abnormalities.” The key criteria for the diagnosis of DED are unstable TF, inflammation, ocular discomfort and visual impairment. This definition also recommends the assessment of ocular surface epitheliopathy and neurosensory abnormalities in each patient with suspected DED. It is easily applicable in clinical practice and should help practitioners diagnose DED consistently. This consensus definition of DED should also help to guide research and clinical trials that, to date, have been hampered by the lack of an established surrogate endpoint. 相似文献
7.
Ross C. Petersen Ian B. McCubbin John A. Ogren Elisabeth Andrews Douglas Lowenthal 《Aerosol science and technology》2019,53(6):712-727
The use of inlets for transferring aerosols from the environment to instrumentation can introduce uncertainty in the measurement of aerosol properties. Aerosol loss during this process is a non-negligible issue that may bias the subsequent measurements. These loss mechanisms include aspiration at the inlet head and deposition/evaporation/condensation during transport through the sampling lines. Coarse-mode aerosol is significantly impacted by the aspiration and inertial loss mechanisms within an inlet system. This work uses wind tunnel experiments to investigate aerosol losses through the Storm Peak Laboratory’s (SPL) new aerosol inlet system. The inlet is used extensively for both intensive field campaigns and long-term aerosol monitoring. The results of numerical simulations of the SPL aerosol inlet sampling efficiency are provided at several wind speeds, and experimental results demonstrate the system has a 50% cut off for the coarse-mode at an aerodynamic diameter of approximately 13?μm and wind speed of 0.5?m s?1. This investigation will lead to improved accuracy of in situ aerosol measurements at SPL and this system can be replicated at other atmospheric stations.
Copyright © 2019 American Association for Aerosol Research 相似文献
8.
The increased use of carbon fiber reinforced thermosets generates more waste and end-of-life products. However, an efficient recycling method for the expensive carbon fibers has not yet been developed. The selective decomposition of amine-cured epoxy resin under mild conditions is presented. A two-step method was investigated to decompose the epoxy resin. The optimum parameters were initially determined using a model compound. By analysis of the reaction products, a cleavage of the C–N bond according to the Cope elimination could be proven. Therefore, the Cope elimination is suggested as the main step of the decomposition of amine-cured epoxy resins in presence of hydrogen peroxide. By dissolving the resin, it is possible to recover resin-free fibers with unimpaired mechanical properties. 相似文献
9.
10.
Raul Pereira Pavol Ondrisek Albeta Kubincov Elisabeth Otth Jn Cvengro 《Advanced Synthesis \u0026amp; Catalysis》2016,358(17):2739-2744
Introduction of oxygen and nitrogen into organic molecules is one of the fundamental strategies for their functionalization. Traditional approaches rely on the formation of an activated intermediate, which is then modified in a subsequent step. Here we report a simple direct oxidative α‐acetoxylation and azidation of α‐C−H bonds in Tröger's base analogues promoted by N‐bromosuccinimide (NBS) and palladium(II)acetate [Pd(OAc)2] under mild conditions. This approach is pivotal on NBS oxidizing the carbon atoms next to the nitrogen atoms in the presence of Pd(OAc)2 followed by a reaction with oxygen‐ or nitrogen‐centred nucleophiles such as KOAc or NaN3 to yield either the mono‐ and bisacetoxylated or azidated Tröger's base derivatives in a stereo‐ and chemoselective manner. The obtained products can be efficiently modified to access synthetically meaningful structures.