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121.
122.
Extensive research works have been done on using magnetic fields on biological organism, but the results till date have been controversial [D.O. Carpenter, S. Ayrapetyan (Eds.), Biological Effects of Electric and Magnetic Fields, vol. 1, Academic Press, San Diego, 1994]. In spite of this, the study of surface magnetic effects on bacterial adhesion and cell growth has not been rigorously explored. The effects of surface magnetism, using perpendicularly polarized magnetic media, are evaluated on Bacillus licheniformis, a widely used bacterium in brewery [L. Kandra, a-Amylases of medical and industrial importance. J. Mol. Struct. (Theochem.), in press] and pharmaceutical [H. Ikram-ul et al., Production of alph amylase by Bacillus licheniformis using an economical medium. Bioresour. Technol. 87 (2003) 57-61] industries, by observing its adhesion and growth behavior. At different spin directions, we are able to observe a change on the biofilm formation, protein synthesis, and cell growth rate. Given that surface energy can easily penetrate through cells, this approach is an advantage over existing techniques that require direct physical contact to target cells. It also presents a new technique to cell adhesion and synthesis of surface proteins. 相似文献
123.
Petrashov VT Chua KG Marshall KM Shaikhaidarov RSh Nicholls JT 《Physical review letters》2005,95(14):147001
Using the extraordinary sensitivity of Andreev interferometers to the superconducting phase difference associated with currents, we measure the persistent current quantum states in superconducting loops interrupted by Josephson junctions. Straightforward electrical resistance measurements of the interferometers give a continuous readout of the states, allowing us to construct the energy spectrum of the quantum circuit. The probe is estimated to be more precise and faster than previous methods, and can measure the local phase difference in a wide range of superconducting circuits. 相似文献
124.
The steady-state simulation of a gas transmission network involves the solution of a system of nonlinear algebraic equations subject to a set of inequality constraints. The purpose of this paper is to consider how the problem can be cast into a variational inequality framework using the dual extremum principles described by Noble and Sewell in 1972. The reliability of the model is tested on two networks supplied by the British Gas Corporation. 相似文献
125.
Four 3–L aerobic biofilm reactors (ABRI, 2, 3, and 4) treating a highstrength food–processing waste water (10 g chemical oxygen
demand [COD]/L) were subject to reactor liquor recirculation rates of 1, 3,15, and 30 L/h, respectively. Treatment performance
in terms of COD removal rates of ABRI, 2, and 3 were similar at hydraulic loads of 2.0 g COD/L/d and below. At higher organic
loads, ABR3 could achieve a COD removal rate that was over two times higher than that of ABRI and 2. ABR3 could be operated
at a maximum organic load that was two times higher than that of ABRI and 2. ABR4 experienced a biofilm sloughing from the
packing medium at the beginning of operation. Tracer studies showed that recirculation rate of 1 L/h resulted in a plug–flow
pattern in the packed bed of the reactor. On the other hand, recirculation rate of 15 L/h, which was equivalent to recirculating
the reactor liquor five times per hour, provided effective mixing in the packed bed. Superior performance of ABR3 was attributed
to the effective recirculation of reactor liquor, which diluted and distributed the influent, particularly the oil and grease
components. 相似文献
126.
S. Y. Xie S. F. Yoon S. Z. Wang Z. Z. Sun P. Chen S. J. Chua 《Journal of Crystal Growth》2004,260(3-4):366-371
Undoped and Be-doped InGaAsN layers were grown on GaAs substrates under the same growth conditions by radio frequency plasma-assisted molecular beam epitaxy. Increased tensile strain (Δa/a=3×10−3) was observed for Be-doped InGaAsN layers, compared to undoped InGaAsN layers. The strain is shown to originate from the increase in N composition related to Be incorporation, rather than solely from Be atoms substituting Ga atom sites (BeGa). A possible reason is the high Be–N bond strength, which inhibits the loss of N from the growth surface during epitaxial growth, thereby increasing the N composition in the Be-doped InGaAsN layer. 相似文献
127.
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129.
Law Kin-Ho Leung Yun-Chung Lawford Hugh Chua Hong Lo Wai-Hung Yu Peter Hoifu 《Applied biochemistry and biotechnology》2001,91(1-9):515-524
Plastic wastes are considered to be severe environmental contaminants causing waste disposal problems. Widespread use of biodegradable
plastics is one of the solutions, but it is limited by high production cost. Biologic wastewater treatment generates large
quantities of biomass as activated sludge. Only a few reports focus on the potential of utilizing resident Bacillus species from activated sludge in polyhydroxbutyrate (PHB) production as well as the production of PHB from food wastes. They
have attractive properties such as short generation time, absence of endotoxins, and secretion of both amylases and proteinases
that can well utilize food wastes for nutrients, which can further reduce the cost of production of polyhydroxyalkanoates
(PHAs). Two PHA-producing strains, HF-1 and HF-2, were isolated from activated sludge. HF-1 outperfomed HF-2 in terms of growth
and PHB production in hydrolyzed soy and malt wastes. The isolated bacteria was characterized by DNA sequence alignment. Cell
extracts of HF-1 were also compared to Bacillus megaterium cell extracts on sodium dodecyl sulfate polyacrylamide gel electrophoresis. The biopolymers accumulated were analyzed by
gas chromatography, nuclear magnetic resonance, and Fourier transform infrared methods. 相似文献
130.
Vachiranee Limviphuvadh Ling Ling Chua Rabi 'Atul' Adawiyah Bte Rahim Frank Eisenhaber Sebastian Maurer-Stroh Sharmila Adhikari 《BMC biochemistry》2010,11(1):39