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1.
Scott Charles D. Woodward Charlene A. Thompson James E. Blankinship Stephen L. 《Applied biochemistry and biotechnology》1990,24(1):799-815
Applied Biochemistry and Biotechnology - Both oxidative and reductive enzymes can be utilized to enhance coal solubilization in aqueous and organic media. Aerobic solubilization was carried out... 相似文献
2.
Charlene S. Chua Simon P. A. Higgins Andreas Fouras 《Journal of synchrotron radiation》2010,17(5):624-630
A high‐repetition‐rate mechanical shutter with asynchronous control and sub‐millisecond operation has been developed and tested for specialist X‐ray systems in the field of medical diagnostics and radiation therapy. Capacitor‐coupled linear voice coil actuators are utilized to achieve opening and closing speeds as fast as 700 µs for an aperture height of 4 mm. The design allows for asynchronous control, permitting slave operation of the shutter, a feature that is distinctly suitable for a number of applications including particle image velocimetry, where high‐frame‐rate operation must be accurately synchronized and triggered by the image acquisition sequence of the detector or timing device. The design and construction of the shutter also makes it ideal, with simple and limited modifications, for applications requiring larger apertures, in particular wide beams as found in many synchrotron beamlines. 相似文献
3.
Hosein Tafazolian Sudarsan VenkatRamani Charlene Tsay Richard R. Schrock Peter Müller 《Helvetica chimica acta》2020,103(6):e2000068
3,3′,5,5′-Tetra-tert-butyl-2′-sulfanyl[1,1′-biphenyl]-2-ol (H2[tBu4OS]) was prepared in 24 % yield overall from the analogous biphenol using standard techniques. Addition of H2[tBu4OS] to Mo(NAr)(CHCMe2Ph)(2,5-dimethylpyrrolide)2 led to formation of Mo(NAr)(CHCMe2Ph)[tBu4OS], which was trapped with PMe3 to give Mo(NAr)(CHCMe2Ph)[tBu4OS](PMe3) ( 1 (PMe3)). An X-ray crystallographic study of 1 (PMe3) revealed that two structurally distinct square pyramidal molecules are present in which the alkylidene ligand occupies the apical position in each. Both 1 (PMe3)A and 1 (PMe3)B are disordered. Mo(NAd)(CHCMe2Ph)(tBu4OS)(PMe3) ( 2 (PMe3); Ad=1-adamantyl) and W(NAr)(CHCMe2Ph)(tBu4OS)(PMe3) ( 3 (PMe3)) were prepared using analogous approaches. 1 (PMe3) reacts with ethylene (1 atm) in benzene within 45 minutes to give an ethylene complex Mo(NAr)(tBu4OS)(C2H4) ( 4 ) that is isolable and relatively stable toward loss of ethylene below 60 °C. An X-ray study shows that the bond distances and angles for the ethylene ligand in 4 are like those found for bisalkoxide ethylene complexes of the same general type. Complex 1 (PMe3) in the presence of one equivalent of B(C6F5)3 catalyzes the homocoupling of 1-decene, allyltrimethylsilane, and allylboronic acid pinacol ester at ambient temperature. 1 (PMe3), 2 (PMe3), and 3 (PMe3) all catalyze the ROMP of rac-endo,exo-5,6-dicarbomethoxynorbornene (rac-DCMNBE) in the presence of B(C6F5)3, but the polyDCMNBE that is formed has a random structure. 相似文献
4.
This paper describes the implementation of a fire field model in the parallel computing environment offered by multiple transputers. The fire model is built into the general purpose SIMPLE-based CFD code HARWELL-FLOW3D. The technique of domain decomposition has been applied tb convert the conventional serial version of FLOW3D into a code capable of efficiently utilizing an arbitrary number of transputers. Fire simulations consisting of up to 24 000 computational cells are performed on parallel systems with up to 15-processors. The run time for this simulation has been reduced from over 4 days on a single processor to just over 8 h on the 15-processor system. An interactive graphics system has also been developed which runs in parallel with the main computations. 相似文献
5.
Selective mode excitation in hollow-core photonic crystal fiber 总被引:2,自引:0,他引:2
Galea AD Couny F Coupland S Roberts PJ Sabert H Knight JC Birks TA Russell PS 《Optics letters》2005,30(7):717-719
Modes are selectively excited by launching light through the cladding from the side into a hollow-core photonic crystal fiber. Measuring the total output power at the end of the fiber as a function of the angle of incidence of the exciting laser beam provides a powerful diagnostic for characterizing the cladding bandgap. Furthermore, various types of modes on either side of the bandgap are excited individually, and their nearfield images are obtained. 相似文献
6.
The authors use a common theme of SHARKS to illustrate the process of developing an interdisciplinary unit for middle school instruction. A model is presented for teams to use in developing integrated curriculum. Focusing on a central theme or topic, a web of disciplines and key concepts is developed. As activities evolve, a concept map is created to illustrate the relationships and integration of ideas and activities. 相似文献
7.
Determination of four acidic nonsteroidal anti‐inflammatory drugs in wastewater samples by dispersive liquid–liquid microextraction based on solidification of floating organic droplet and high‐performance liquid chromatography
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Mihail Simion Beldean‐Galea Virginia Coman Didier Thiébaut Jérome Vial 《Journal of separation science》2015,38(4):641-648
A simple, environmentally friendly, and sensitive dispersive liquid–liquid microextraction based on solidification of floating organic droplet for the extraction of four acidic nonsteroidal anti‐inflammatory drugs (ketoprofen, naproxen, ibuprofen, and diclofenac) from wastewater samples subsequent by high‐performance liquid chromatography analysis was developed. The influence of extraction parameters such as pH, the effect of solution ionic strength, type of extraction solvent, disperser solvent, and extraction solvent volume were studied. High enrichment factors (283–302) were obtained through the developed method. The method provides good linearity (r > 0.999) in a concentration range of 1–100 μg/L, good intra‐ and inter‐day precision (relative standard deviation < 7%) and low limits of quantification. The relative recoveries of the selected compounds were situated over 80% both in synthetic and real water samples. The developed method has been successfully applied for the analysis of the selected compounds in wastewater samples. 相似文献
8.
Tungsten oxide (WO(3)) electrodes subjected to a positive bias are self-photorecharged with alkali cations in the electrolyte during visible light illumination. Upon photoexcitation, part of the photogenerated charges generated by WO(3) is stabilized by the cations and stored in situ within the WO(3) framework. This light-induced storage of charges is subsequently utilized in dark conditions in an on-demand manner and is able to be recharged in the successive illumination cycles. The amount of charges stored is shown to be dependent on the cation ionic radii and the presence of these intercalated cations is verified by X-ray diffraction (XRD) and inductively coupled plasma mass spectroscopy (ICP-MS). This self-photorecharge and on-demand charge-release phenomena demonstrate the ability of WO(3) to supply photoexcited charges under dark condition in a photoelectrochemical reaction with greater flexibility. 相似文献
9.
The selectivity and response of neutral carrier based polymer membrane electrodes are investigated via exchange current measurements for systems containing valinomycin, dibenzo-18-crown-6, and plasticizer alone in a polyvinyl chloride matrix. Using a transient galvanostatic step method, apparent exchange current densities of 1.3 X 10?3 A/cm2, 5.4 X 10?6 A/cm2, and 2.2 X 10?9 A/cm2 were obtained with K+ as the primary ion for the three types of membranes, respectively. Preliminary results indicate that the exchange current data obtained with this technique are complementary to the potentiometric response observed for the membranes studied. 相似文献
10.
Dr. Thomas G. Hayhow Rachel E. A. Borrows Dr. Coura R. Diène Gary Fairley Dr. Charlene Fallan Dr. Shaun M. Fillery Dr. James S. Scott Dr. David W. Watson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(70):16818-16823
A palladium-catalysed Buchwald–Hartwig amination for lenalidomide-derived aryl bromides was optimised using high throughput experimentation (HTE). The substrate scope of the optimised conditions was evaluated for a range of alkyl- and aryl- amines and functionalised aryl bromides. The methodology allows access to new cereblon-based bifunctional proteolysis targeting chimeras with a reduced step count and improved yields. 相似文献