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51.
Proteins were extracted from the deoiled seeds ofEucalyptus kirtoniana in aqueous solutions of various pHs or by different concentrations of NaCl, Na2SO3, CaCl2 and MgCl2 at pH 8.0. Amino acid analysis of the isolated protein identified 16 amino acids, nine of which were essential. Gel permeation
chromatography on Sephadex G-200 revealed the presence of four components in the protein fraction, and their molecular weights
were determined by two comparable standard methods. SDS-PAG electrophoresis demonstrated that each protein isolate from different
salt solutions was composed of six fractions whose molecular weights were estimated to be 131,800; 108,300; 93,300; 51,300;
38,000 and 25,700 daltons. 相似文献
52.
53.
Vachaspati T 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2008,366(1877):2915-2923
The COSLAB effort has focused on the formation of topological defects during phase transitions. Yet there is another potentially interesting signature of cosmological phase transitions, which also deserves study in the laboratory. This is the generation of magnetic fields during phase transitions. In particular, cosmological phase transitions that also lead to preferential production of matter over antimatter ('baryogenesis') are expected to produce helical (left-handed) magnetic fields. The study of analogous processes in the laboratory can yield important insight into the production of helical magnetic fields, and the observation of such fields in the Universe can be invaluable for both particle physics and cosmology. 相似文献
54.
Optimal reactive power dispatch (ORPD) is a complex and non-linear problem, and is one of the sub-problems of
optimal power flow (OPF) in a power system. ORPD is formulated as a single-objective problem to minimize the
active power loss in a transmission system. In this work, power from distributed generation (DG) is integrated into a
conventional power system and the ORPD problem is solved to minimize transmission line power loss. It proves
that the application of DG not only contributes to power loss minimization and improvement of system stability
but also reduces energy consumption from the conventional sources. A recently proposed meta-heuristic algorithm
known as the JAYA algorithm is applied to the standard IEEE 14, 30, 57 and 118 bus systems to solve the newly
developed ORPD problem with the incorporation of DG. The simulation results prove the superiority of the JAYA
algorithm over others. The respective optimal values of DG power that should be injected into the four IEEE test
systems to obtain the minimum transmission line power losses are also provided. 相似文献
55.
Delayed Fluorescence Emitters: Efficient and Tunable Thermally Activated Delayed Fluorescence Emitters Having Orientation‐Adjustable CN‐Substituted Pyridine and Pyrimidine Acceptor Units (Adv. Funct. Mater. 42/2016) 下载免费PDF全文
56.
Basak A Mitra A Basak S Pasko C Chrétien M Seaton P 《Chembiochem : a European journal of chemical biology》2007,8(9):1029-1037
Human severe acute respiratory syndrome coronavirus (hSARS-CoV) is the causative agent for SARS infection. Its surface glycoprotein (spike protein) is considered to be one of the prime targets for SARS therapeutics and intervention because its proteolytic maturation by a host protease is crucial for host-virus fusion. Using intramolecularly quenched fluorogenic (IQF) peptides based on hSARS-CoV spike protein (Abz-(755)Glu-Gln-Asp-Arg-Asn-Thr-Arg-Glu-Val-Phe-Ala-Gln(766)-Tyx-NH(2)) and in vitro studies, we show that besides furin, other PCs, like PC5 and PC7, might also be involved in this cleavage event. Through kinetic measurements with recombinant PCs, we observed that the peptide was cleaved efficiently by both furin and PC5, but very poorly by PC7. The cleavage could be blocked by a PC-inhibitor, alpha1-PDX, in a dose-dependent manner. Circular dichroism spectra indicated that this peptide possesses a high degree of sheet structure. Following cleavage by furin, the sheet content increased, possibly at the expense of turn and random structures. (1)H NMR spectra from 2D COSY and ROESY experiments under physiological buffer and pH conditions indicated that this peptide possesses a structure with a turn at its C-terminal segment, close to the cleavage site. The data suggest that the cleavable peptide bond is located within the most exposed domain; this is supported by the nearby turn structure. Several strong to weak NMR ROESY correlations were detected, and a 3D structure of the spike IQF peptide that contains the crucial cleavage site R(761) E has been proposed. 相似文献
57.
The phenomena of natural convection in a right-angled triangular enclosure is studied numerically. A penalty finite element analysis with bi-quadratic elements is used for solving the Navier-Stokes and energy balance equations. The detailed study is carried out in two cases depending on various thermal boundary conditions:
- (a)
- Vertical wall is uniformly or linearly heated while inclined wall is cold isothermal.
- (b)
- Inclined wall is uniformly or linearly heated while vertical wall is cold isothermal.
58.
The present work concerns an assessment of the influence of boron addition in spheroidal graphite iron (SG iron) melt on the manufacturing process and final properties of DI pipes. To elicit the effect of boron addition on the final properties of DI pipe, initially laboratory scale trials were conducted. The exercise includes studying the evolution of microstructure and mechanical properties of DI pipes with different level of boron addition. The results indicate that the presence of B in the melt does not have any perceptible deleterious effect on the performance of DI pipes in general, until the limit goes beyond 200?ppm. Later on, pilot trials were conducted in a plant facility. This trial comprises addition of boron at different levels in SG iron melts and studying effect on the overall manufacturing process of DI pipe production and corresponding microstructure and mechanical properties of the final product (i.e. DI pipes). The result of the plant-level trial is found in agreement with the laboratory scale trial, confirming the fact that presence of boron up to 200?ppm level in SG iron melt used for DI pipe manufacturing does not induce any deleterious effect on manufacturing process as well as product properties. Also, it reveals that the boron-added (up to 200?ppm) DI pipes show better machinability with a favourable combination of strength, ductility and hardness compared to the boron-free DI pipes. 相似文献
59.
Abhishek Kumar Singh S. Roy Tanmay Basak 《International Journal of Heat and Mass Transfer》2012,55(11-12):2965-2983
This article analyzes the detailed heat transfer phenomena during natural convection within tilted square cavities with isothermally cooled walls (BC and DA) and hot wall AB is parallel to the insulated wall CD. A penalty finite element analysis with bi-quadratic elements has been used to investigate the results in terms of streamlines, isotherms and heatlines. The present numerical procedure is performed over a wide range of parameters (103 ? Ra ? 105,0.015 ? Pr ? 1000,0° ? φ ? 90°). Secondary circulations cells are observed near corner regions of cavity for all φ’s at Pr = 0.015 with Ra = 105. Two asymmetric flow circulation cells are found to occupy the entire cavity for φ = 15° at Pr = 0.7 and Pr = 1000 with Ra = 105. Heatlines indicate that the cavity with inclination angle φ = 15° corresponds to large convective heat transfer from the wall AB to wall DA whereas the heat transfer to wall BC is maximum for φ = 75°. Heat transfer rates along the walls are obtained in terms of local and average Nusselt numbers and they are explained based on gradients of heatfunctions. Average Nusselt number distributions show that heat transfer rate along wall DA is larger for lower inclination angle (φ = 15°) whereas maximum heat transfer rate along wall BC occur for higher inclination angle (φ = 75°). 相似文献
60.
D. Ramakrishna Tanmay Basak S. Roy I. Pop 《International Journal of Heat and Mass Transfer》2012,55(21-22):5436-5448
The present numerical study deals with mixed convection flows within square enclosures filled with porous media. The influence of various thermal boundary conditions on bottom and side walls based on thermal aspect ratio (A) is investigated for a wide range of parameters (1 ? Re ? 100, 0.015 ? Pr ? 7.2, 10?5 ? Da ? 10?3 and 103 ? Gr ? 105). A penalty finite element method with bi-quadratic elements has been used to investigate the results in terms of streamlines, isotherms and heatlines and average Nusselt numbers. Lid driven effect is dominant at low Darcy number (Da = 10?5), whereas buoyancy driven effect is dominant at high Darcy numbers (Da = 10?4 and Da = 10?3) for Re = 1. Asymmetric pattern is observed in isotherms and heatlines for Re = 100. It is found that thermal gradient is high at the center of the bottom wall for A = 0.1 due to large dense heatlines at that zone and that is low for A = 0.9 irrespective of Re, Pr and Gr. Overall heat transfer rates are higher for A = 0.1 compared to other thermal aspect ratios (A = 0.5, A = 0.9) irrespective of Darcy number, Prandtl number and Reynolds number. 相似文献