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排序方式: 共有160条查询结果,搜索用时 18 毫秒
31.
Nayak Debasis Dora J. K. Ghosh Sudipto Adyam Venimadhav 《Journal of Solid State Electrochemistry》2022,26(5):1231-1239
Journal of Solid State Electrochemistry - Sodium-ion batteries have emerged as an exciting alternative to commercially dominant lithium-ion batteries for electric vehicles and other applications.... 相似文献
32.
Prof. Dr. Petra Schwille Prof. Dr. Joachim Spatz Prof. Dr. Katharina Landfester Prof. Dr. Eberhard Bodenschatz Prof. Dr. Stephan Herminghaus Prof. Dr. Victor Sourjik Dr. Tobias J. Erb Prof. Dr. Philippe Bastiaens Prof. Dr. Reinhard Lipowsky Prof. Dr. Anthony Hyman Prof. Dr. Peter Dabrock Dr. Jean‐Christophe Baret Dr. Tanja Vidakovic‐Koch Dr. Peter Bieling Dr. Rumiana Dimova Dr. Hannes Mutschler Dr. Tom Robinson Dr. T.‐Y. Dora Tang Dr. Seraphine Wegner Prof. Dr. Kai Sundmacher 《Angewandte Chemie (International ed. in English)》2018,57(41):13382-13392
A large German research consortium mainly within the Max Planck Society (“MaxSynBio”) was formed to investigate living systems from a fundamental perspective. The research program of MaxSynBio relies solely on the bottom‐up approach to synthetic biology. MaxSynBio focuses on the detailed analysis and understanding of essential processes of life through modular reconstitution in minimal synthetic systems. The ultimate goal is to construct a basic living unit entirely from non‐living components. The fundamental insights gained from the activities in MaxSynBio could eventually be utilized for establishing a new generation of biotechnological processes, which would be based on synthetic cell constructs that replace the natural cells currently used in conventional biotechnology. 相似文献
33.
Zusammenfassung Es wurde festgestellt, da? beim Mischen von Quecksilbersol und Schwefelsol kolloides Sulfid entsteht. Und zwar konnte dies
dadurch nachgewiesen werden, da? überschüssiger Schwefel aus dem Gemisch der ausgeflockten Kolloide durch Ausziehen mit Natriumsulfitl?sung
entfernt wurde, worauf der Rückstand als Merkurisulfid identifiziert werden konnte.
In analoger Weise wie früher bei Kupfer- und Schwefelsol konnte gezeigt werden, da? auch hier die kolloiden Stoffe die Reaktionstr?ger
sind.
Die Umsetzung zwischen kolloidem Quecksilber und Schwefel verlief wesentlich weniger schnell als zwischen Kupfer und Schwefel.
So konnte noch eine gewisse Zeit nach dem Zusammengeben der Sole trotz Anwendung eines überschusses an kolloidem Schwefel
nicht gebundenes Quecksilber bzw. umgekehrt bei überschüssigem Quecksilber freier Schwefel nachgewiesen werden. 相似文献
34.
A. Dora R. Pontinha S. Carlos B. Oliveira Ana Maria Oliveira‐Brett 《Electroanalysis》2008,20(23):2531-2536
Metolazone is a diuretic agent used in patients with edematous states and/or hypertension. The electrochemical behavior of metolazone on a glassy carbon electrode was investigated using cyclic, differential pulse, and square‐wave voltammetry at different pHs. The pH dependent oxidation of metolazone occurs in two consecutive steps in a diffusion‐controlled mechanism and involves the formation of a main oxidation product. The first oxidation process is reversible, and involves two electrons and two protons corresponding to the oxidation of nitrogen in the sulfonamide moiety. The second oxidation process is irreversible, also occurs in the sulfonamide moiety, involves a one electron‐transfer, and is followed by deprotonation to produce a cation radical, which reacts with water and yields a hydroxylated product. The diffusion coefficient of metolazone was calculated to be 3.43×10?6 cm2 s?1 in pH 7.0 0.1 M phosphate buffer. 相似文献
35.
Pier Giovanni Baraldi Francesca Fruttarolo Mojgan Aghazadeh Tabrizi Romeo Romagnoli Delia Preti Ennio Ongini Hussein El‐Kashef María Dora Carrión Pier Andrea Borea 《Journal of heterocyclic chemistry》2007,44(2):355-361
The reaction between 3‐(dimethylamino)/3,3‐bis(methylthio)‐1‐(substituted)prop‐2‐en‐1‐ones and 4‐substituted‐5‐amino‐1H‐pyrazoles afforded new pyrazole[1,5‐a]pyrimidines structurally related to Zaleplon. The chemical modifications introduced at the 3‐, 5‐, and 7‐positions of the bicyclic structure revealed new promising candidates for the treatment of sleep disorders. 相似文献
36.
Fourteen collaborating laboratories assayed maleic hydrazide (MH), 6-hydroxypyridazin-3(2H)-one, in technical and formulated products by reversed-phase liquid chromatography (LC) with sulfanilic acid as an internal standard. The active MH in the samples (6 lots) ranged from 16% (expressed as the potassium salt) to 98% (MH in the technical). A small amount of 1 M KOH was added to the technical MH and analytical standards to create the potassium salt of the analyte which is soluble in water. Test samples and standards were extracted with water containing the internal standard before analysis by LC on a C8 column with an ion-pairing eluting solution and UV detection at 254 nm. The concentration of MH was calculated by comparing the peak area response ratios of the analyte and the internal standard with those in the analytical standard solution. Eleven laboratories weighed each test sample twice with single analysis. Three laboratories weighed each sample once and made duplicate injections on the LC system. The data were analyzed using the 11 laboratories' results. A second data analysis was done including all laboratory results using a Youden pair approach, selecting one of 2 duplicate assay values randomly for each laboratory and sample. In the first data analysis, the repeatability standard deviation ranged from 0.07 to 1.39%; reproducibility standard deviation ranged from 0.22 to 1.39%. In the second data analysis (using all laboratory data), repeatability standard deviation ranged from 0.09 to 0.86%; reproducibility standard deviation ranged from 0.22 to 1.31%. 相似文献
37.
Formation and evolution of a compressible vortex ring generated at the open end of a short driver section shock tube has been
simulated numerically for pressure ratios (PR) of 3 and 7 in the present study. Numerical study of compressible vortex rings
is essential to understand the complicated flow structure and acoustic characteristics of many high Mach number impulsive
jets where simultaneously velocity, density and pressure fields are needed. The flow development, incident shock formation,
shock diffraction, vortex ring formation and its evolution are simulated using the AUSM+ scheme. The main focus of the present
study is to evaluate the time resolved vorticity field of the vortex ring and the shock/expansion waves in the starting jet
for short driver section shock tubes—a scenario where little data are available in existing literature. An embedded shock
and a vortex induced shock are observed for PR = 7. However the vortex ring remains shock free, compact and unaffected by
the trailing jet for PR = 3. Numerical shadowgraph shows the evolution of embedded shock and shock/expansion waves along
with their interactions. The velocity and vorticity fields obtained from simulation are validated with the particle image
velocimetry results and these data match closely. The translational velocity of the vortex ring, velocity across the vortex
and the centre line velocity of the jet obtained from simulation also agree well with the experimental results. 相似文献
38.
39.
Andrea Gmez-Maqueo Dora Steurer Jorge Welti-Chanes M. Pilar Cano 《Molecules (Basel, Switzerland)》2021,26(17)
High hydrostatic pressure (HHP) is a commercial processing technology which can enhance the health potential of foods by improving the bioaccessibility of their bioactive compounds. Our aim was to study the bioaccessibility and digestive stability of phenolic compounds and betalains in prickly pear fruits (Opuntia ficus-indica L. Mill. var. Pelota and Sanguinos) treated with HHP (100, 350, and 600 MPa; come-up time and 5 min). The effects of HHP on pulps (edible fraction) and peels (sources of potential healthy ingredients) were assessed. In pulps, betanin bioaccessibility increased (+47% to +64%) when treated at 350 MPa/5 min. In HHP-treated pulps, increases in the bioaccessibility of piscidic acid (+67% to +176%) and 4-hydroxybenzoic acid glycoside (+126% to 136%) were also observed. Isorhamnetin glycosides in peels treated at 600 MPa/CUT had higher bioaccessibility (+17% to +126%) than their controls. The effects of HHP on the bioaccessibility of health-promoting compounds are not exclusively governed by extractability increases of antioxidants in the food matrix (direct effects). In this work we found evidence that indirect effects (effects on the food matrix) could also play a role in the increased bioaccessibility of antioxidants in fruits treated with HHP. 相似文献
40.
We propose and demonstrate a novel and simple dual-parameter measurement scheme based on a cascaded optical fiber device of long-period grating (LPG) and photonic crystal fiber (PCF) modal interferometer. The temperature and refractive index (RI) can be measured simultaneously by monitoring the spectral characteristics of the device. The implemented sensor shows distinctive spectral sensitivities of -30.82 nm/RIU (refractive index unit) and 47.4 pm/°C by the LPG, and 171.96 nm/RIU and 10.4 pm/°C by the PCF modal interferometer. The simultaneous measurement of the temperature and external RI is experimentally demonstrated by the sensor. The temperature shift and RI shift calculated by the sensor matrix agree well with the actual temperature and RI change in the experiment. 相似文献