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991.
We prove the following: Let A and B be separable C*-algebras. Suppose that B is a type I C*-algebra such that
- (i)
- B has only infinite dimensional irreducible *-representations, and
- (ii)
- B has finite decomposition rank.
0→B→C→A→0 相似文献
992.
Detailed measurements of particle in-flight characteristics have been carried out using a PDA system for benchmarking as well as to provide further information to aid the development of simulation models. The parameters studied included four conditions of primary gas flow rate and carrier gas flow rate. The particle velocities, diameters, and the corresponding volume flux at different locations were obtained. Due to the one port particle injection arrangement, it was noted that particles in general sprayed with an angle deviated from the nozzle axis Zn, to the opposite side of the powder feeder port. The particles would also deviate from the spraying cone axis with a divergence angle (). The deviation and divergence angles were examined under different plasma spraying conditions. The measurement data rates at different cross-sectional planes were also obtained so as to compare the results derived from the volume flux measurement and the actual coating on a substrate at the equivalent standoff distance. It was found that the spraying area obtained from the measurement-data-rate increased with downstream distance and a linear relationship between spraying area and distance was also established. Comparing the integrated results, it was noted that the spraying areas derived from the measurement data rate were close to the actual spraying areas obtained from the coordinate measurement machine (CMM) results. 相似文献
993.
A novel approach appropriate for rapid separation and immobilization of a single cell by concomitantly utilizing laser manipulation and locally thermosensitive hydrogelation is proposed in this paper. We employed a single laser beam as optical tweezers for separating a target cell and locating it adjacent to a fabricated, transparent micro heater. Simultaneously, the target cell is immobilized or partially entrapped by heating the thermosensitive hydrogel with the micro heater. The state of the thermosensitive hydrogel can be switched from sol to gel and gel to sol by controlling the temperature through heating and cooling by the micro heater. After other unwanted cells are removed by the high-speed cleaning flow in the microchannel, the entrapped cell is successfully isolated. It is possible to collect the immobilized target cell for analysis or culture by switching off the micro heater and releasing the cell from the entrapment. We demonstrated that the proposed approach is feasible for rapid manipulation, immobilization, cleaning, isolation and extraction of a single cell. The experimental results are shown here. 相似文献
994.
We consider the resonant optical force acting on a pair of transparent microspheres by the excitation of morphology-dependent resonance (MDR). The bonding and antibonding modes of the MDR correspond to strong attraction and repulsion, respectively. The dependence of the force on separation and the role of absorption are discussed. At resonance, the force can be enhanced by orders of magnitude such that it will dominate other relevant forces. We found that a stable binding configuration can be induced by the resonant optical force. 相似文献
995.
996.
997.
Photocorrosion of Cuprous Oxide in Hydrogen Production: Rationalising Self‐Oxidation or Self‐Reduction 下载免费PDF全文
Cui Ying Toe Prof. Zhaoke Zheng Hao Wu Prof. Jason Scott Prof. Rose Amal Dr. Yun Hau Ng 《Angewandte Chemie (International ed. in English)》2018,57(41):13613-13617
Cuprous Oxide (Cu2O) is a photocatalyst with severe photocorrosion issues. Theoretically, it can undergo both self‐oxidation (to form copper oxide (CuO)) and self‐reduction (to form metallic copper (Cu)) upon illumination with the aid of photoexcited charges. There is, however, limited experimental understanding of the “dominant” photocorrosion pathway. Both photocorrosion modes can be regulated by tailoring the conditions of the photocatalytic reactions. Photooxidation of Cu2O (in the form of a suspension system), accompanied by corroded morphology, is kinetically favourable and is the prevailing deactivation pathway. With knowledge of the dominant deactivation mode of Cu2O, suppression of self‐photooxidation together with enhancement in its overall photocatalytic performance can be achieved after a careful selection of sacrificial hole (h+) scavenger. In this way, stable hydrogen (H2) production can be attained without the need for deposition of secondary components. 相似文献
998.
Trefoil‐Shaped Porous Nanographenes Bearing a Tribenzotriquinacene Core by Three‐fold Scholl Macrocyclization 下载免费PDF全文
Dr. Lisi He Dr. Chun‐Fai Ng Yuke Li Prof. Zhifeng Liu Prof. Dietmar Kuck Prof. Hak‐Fun Chow 《Angewandte Chemie (International ed. in English)》2018,57(41):13635-13639
Porous curved polycyclic aromatic compounds 6 and 14 bearing a tribenzotriquinacene (TBTQ) core encircled by an m,p,p,m,m,p,p,m,m,p,p,m‐cyclododecaphenylene belt were synthesized and characterized by NMR spectroscopy and mass spectrometry. These trefoil hydrocarbon macrocycles were constructed in high yield using an intramolecular three‐fold Scholl macrocyclization. X‐ray crystal analysis of 14 demonstrated a large wizard‐hat‐shaped structure with three pores (radii 2.9–3.0 Å). The π‐stacking aggregation of the hexa‐n‐dodecyloxy derivative 6 a and the chloride anion binding properties of 14 were studied by NMR spectroscopy. Such stacking and anion binding properties were much weaker in the singly 11 and doubly macrocyclized products 12 . 相似文献
999.
Prof. Adam J. Gormley Dr. Jonathan Yeow Gervase Ng Órla Conway Prof. Cyrille Boyer Dr. Robert Chapman 《Angewandte Chemie (International ed. in English)》2018,57(6):1557-1562
The complexity of polymer–protein interactions makes rational design of the best polymer architecture for any given biointerface extremely challenging, and the high throughput synthesis and screening of polymers has emerged as an attractive alternative. A porphyrin‐catalysed photoinduced electron/energy transfer–reversible addition‐fragmentation chain‐transfer (PET‐RAFT) polymerisation was adapted to enable high throughput synthesis of complex polymer architectures in dimethyl sulfoxide (DMSO) on low‐volume well plates in the presence of air. The polymerisation system shows remarkable oxygen tolerance, and excellent control of functional 3‐ and 4‐arm star polymers. We then apply this method to investigate the effect of polymer structure on protein binding, in this case to the lectin concanavalin A (ConA). Such an approach could be applied to screen the structure–activity relationships for any number of polymer–protein interactions. 相似文献
1000.
The standardisation of substitutable electrical components within the Canadian Forces is under investigation. The decision control rule on standardisation is based on the sensitivity analysis of the classical (Q, r) inventory control system. Closed-form solutions on the decision rule are obtained using symbolic computations. The merit of our approach is that the solution procedure is simple to understand and can be easily implemented on a hand calculator. 相似文献