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91.
Anthony To-Ming Lau 《Journal of Functional Analysis》2008,254(10):2513-2533
In this paper, we explore the properties of projections of norm one on general Banach algebras, in particular the relation with conditional expectations for algebras which arise in harmonic analysis. 相似文献
92.
In this paper, we shall establish a fixed point property on Fréchet spaces for left reversible semitopological semigroups generalizing some classical results. 相似文献
93.
94.
Eike Lau 《Inventiones Mathematicae》2008,171(3):617-628
Over p-adic Nagata rings, formal p-divisible groups are classified by nilpotent displays according to T. Zink. We extend this result to arbitrary p-adic rings. The proof uses the Grothendieck–Illusie deformation theory of truncated p-divisible groups. 相似文献
95.
In this paper, we study the multi-machine scheduling problem with earliness and tardiness penalties and sequence dependent
setup times. This problem can be decomposed into two subproblems—sequencing and timetabling. Sequencing focuses on assigning
each job to a fixed machine and determine the job sequence on each machine. We call such assignment a semi-schedule. Timetabling
focuses on finding an executable schedule from the semi-schedule via idle-time insertion. Sequencing is strongly NP-hard in
general. Although timetabling is polynomial-time solvable, it can become a computational bottleneck if the procedure is executed
many times within a larger framework. This paper makes two contributions. We first propose a quantum improvement to the computational
efficiency of the timetabling algorithm. We then apply it within a squeaky wheel optimization framework to solve the sequencing
and overall problem. Finally, we demonstrate the strength of our proposed algorithms by experiments. 相似文献
96.
Mark C. Biesinger Brad P. Payne Leo W. M. Lau Andrea Gerson Roger St. C. Smart 《Surface and interface analysis : SIA》2009,41(4):324-332
Quantitative chemical state X‐ray photoelectron spectroscopic analysis of mixed nickel metal, oxide, hydroxide and oxyhydroxide systems is challenging due to the complexity of the Ni 2p peak shapes resulting from multiplet splitting, shake‐up and plasmon loss structures. Quantification of mixed nickel chemical states and the qualitative determination of low concentrations of Ni(III) species are demonstrated via an approach based on standard spectra from quality reference samples (Ni, NiO, Ni(OH)2, NiOOH), subtraction of these spectra, and data analysis that integrates information from the Ni 2p spectrum and the O 1s spectra. Quantification of a commercial nickel powder and a thin nickel oxide film grown at 1‐Torr O2 and 300 °C for 20 min is demonstrated. The effect of uncertain relative sensitivity factors (e.g. Ni 2.67 ± 0.54) is discussed, as is the depth of measurement for thin film analysis based on calculated inelastic mean free paths. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
97.
98.
Ming J. Lau Ming W. Lau Christa Gunawan Bruce E. Dale 《Applied biochemistry and biotechnology》2010,162(7):1847-1857
Empty palm fruit bunch fiber (EPFBF), a readily available cellulosic biomass from palm processing facilities, is investigated
as a potential carbohydrate source for cellulosic ethanol production. This feedstock was pretreated using ammonia fiber expansion
(AFEX) and enzymatically hydrolyzed. The best tested AFEX conditions were at 135 °C, 45 min retention time, water to dry biomass
loading of 1:1 (weight ratio), and ammonia to dry biomass loading of 1:1 (weight ratio). The particle size of the pretreated
biomass was reduced post-AFEX. The optimized enzyme formulation consists of Accellerase (84 μL/g biomass), Multifect Xylanase
(31 μL/g biomass), and Multifect Pectinase (24 μL/g biomass). This mixture achieved close to 90% of the total maximum yield
within 72 h of enzymatic hydrolysis. Fermentation on the water extract of this biomass affirms that nutrients solely from
the pretreated EPFBF can support yeast growth for complete glucose fermentation. These results suggest that AFEX-treated EPFBF
can be used for cellulosic biofuels production because biomass recalcitrance has been overcome without reducing the fermentability
of the pretreated materials. 相似文献
99.
Syahmi AR Vijayarathna S Sasidharan S Latha LY Kwan YP Lau YL Shin LN Chen Y 《Molecules (Basel, Switzerland)》2010,15(11):8111-8121
Elaeis guineensis (Arecaceae) is widely used in West African traditional medicine for treating various ailments. An evaluation on the toxicity of extracts of this plant is crucial to support the therapeutic claims. The acute oral toxicity and brine shrimp lethality of a methanolic extract of this plant was tested. Oral administration of crude extract at the highest dose of 5,000 mg/kg resulted in no mortalities or evidence of adverse effects, implying that E. guineensis is nontoxic. Normal behavioral pattern, clinical signs and histology of vital organs confirm this evidence. The E. guineensis extracts screened for toxicity against brine shrimp had 50% lethal concentration (LC??) values of more than 1.0 mg/mL (9.00 and 3.87 mg/mL, at 6 and 24 h, respectively), confirming that the extract was not toxic. Maximum mortalities occurred at 100 mg/mL concentration while the least mortalities happened to be at 0.195 mg/mL concentration. The results of both tests confirm that E. guineensis is nontoxic and hence safe for commercial utilization. 相似文献
100.
Xu-Yuan Peng Xiao-Xia Liu Pei-Jie Hua Dermot Diamond King-Tong Lau 《Journal of Solid State Electrochemistry》2010,14(1):1-7
Nickel oxide (NiOx) and polyaniline (PAni) were electrocodeposited from NiSO4 and aniline through cyclic voltammetric scans to afford PAni–NiOx composite film at controlled pH environment. The electrochemical activities of the film were investigated by cyclic voltammetry
in 0.1 M NaOH and 0.1 M H2SO4, respectively. Typical redox couples of PAni in 0.1 M H2SO4 appeared at approximately 0.2 and 0.4 V vs. saturated calomel electrode (SCE); Ni(II)/Ni(III) redox couple was observed at
approximately 0.4 V vs. SCE in 0.1 M NaOH. The morphologies and elemental components of the films were inspected by scanning
electron microscopy and energy dispersive X-ray diffraction. The stability of nickel oxide in the films was found to be enhanced
against acidic environments. Electrochemical catalytic behavior of NiOx within the composite film was conserved and demonstrated by catalytic oxidation of methanol and ethanol. 相似文献