1,114 research outputs found
{1,3-Bis[(diphenylphosphanyl-κP)oxy]propane}dicarbonyliron(0)
The structure of the title compound, [Fe(C27H26O2P2)(CO)2], exhibits a distorted tetrahedral coordination [bond angle range = 96.31 (12)–119.37 (4)°], comprising two P-atom donors from the chelating 1,3-bis[(diphenylphosphanyl)oxy]propane ligand [Fe—P = 2.1414 (10) and 2.1462 (10) Å] and two carbonyl ligands [Fe—C = 1.763 (4) and 1.765 (3) Å]
{1,3-Bis[(diphenylphosphanyl-κP)oxy]prop-2-yl-κC 2}iodido(trimethylphosphane)cobalt(II)
The title compound, [Co(C27H25O2P2)I(C3H9P)], was synthesized by the addition of 1-iodobutane to a solution of the parent cobalt complex {1,3-bis[(diphenylphosphanyl)oxy]prop-2-yl}bis(trimethylphosphane)cobalt(II). Two five-membered cobaltocycles with considerable ring bending (sum of internal angles = 516.4 and 517.7°) are formed through two P atoms of the PPh2 groups and a metallated Csp
3 atom. The CoII atom is centered in a trigonal-bipyramidal configuration
Time-triggered State-machine Reliable Software Architecture for Micro Turbine Engine Control
AbstractTime-triggered (TT) embedded software pattern is well accepted in aerospace industry for its high reliability. Finite-state-machine (FSM) design method is widely used for its high efficiency and predictable behavior. In this paper, the time-triggered and state-machine combination software architecture is implemented for a 25 kg thrust micro turbine engine (MTE) used for unmanned aerial vehicle (UAV) system; also model-based-design development workflow for airworthiness software directive DO-178B is utilized. Experimental results show that time-triggered state-machine software architecture and development method could shorten the system development time, reduce the system test cost and make the turbine engine easily comply with the airworthiness rules
Reconstruction of cytosolic fumaric acid biosynthetic pathways in Saccharomyces cerevisiae
<p>Abstract</p> <p>Background</p> <p>Fumaric acid is a commercially important component of foodstuffs, pharmaceuticals and industrial materials, yet the current methods of production are unsustainable and ecologically destructive.</p> <p>Results</p> <p>In this study, the fumarate biosynthetic pathway involving reductive reactions of the tricarboxylic acid cycle was exogenously introduced in <it>S. cerevisiae </it>by a series of simple genetic modifications. First, the <it>Rhizopus oryzae </it>genes for malate dehydrogenase (<it>RoMDH</it>) and fumarase (<it>RoFUM1</it>) were heterologously expressed. Then, expression of the endogenous pyruvate carboxylase (<it>PYC2</it>) was up-regulated. The resultant yeast strain, FMME-001 ↑<it>PYC2 </it>+ ↑<it>RoMDH</it>, was capable of producing significantly higher yields of fumarate in the glucose medium (3.18 ± 0.15 g liter<sup>-1</sup>) than the control strain FMME-001 empty vector.</p> <p>Conclusions</p> <p>The results presented here provide a novel strategy for fumarate biosynthesis, which represents an important advancement in producing high yields of fumarate in a sustainable and ecologically-friendly manner.</p
Sensitivity Analysis and Optimization of a Coal-fired Power Plant in Different Modes of Flue Gas Recirculation
AbstractIn a coal-fired power plant with flue gas recirculation, recirculation rate and coal input have a great effect on the performance of the power plant. In this paper, a 600 MW coal-fired boiler is taken as base case, the main parameters of the boiler are calculated at different recirculation rates and coal input conditions, an optimization is carried out and the optimum recirculation rate and coal input are reported. The results show that under optimum recirculation rate and coal input conditions, the net coal consumption rate can be reduced by 3.5g/(kW·h) at 575MW load; while it is 4.36g/(kW·h) and 5.11g/(kW·h), respectively, at 450MW load and 300MW load. Compared to the conventional flue gas recirculation system, the net coal consumption rate can be reduced by 2.31 g/(kW·h), 2.42 g/(kW·h) and 2.41 g/(kW·h), respectively, at 575MW, 450MW and 300MW load
Context-aware and Scale-insensitive Temporal Repetition Counting
Temporal repetition counting aims to estimate the number of cycles of a given
repetitive action. Existing deep learning methods assume repetitive actions are
performed in a fixed time-scale, which is invalid for the complex repetitive
actions in real life. In this paper, we tailor a context-aware and
scale-insensitive framework, to tackle the challenges in repetition counting
caused by the unknown and diverse cycle-lengths. Our approach combines two key
insights: (1) Cycle lengths from different actions are unpredictable that
require large-scale searching, but, once a coarse cycle length is determined,
the variety between repetitions can be overcome by regression. (2) Determining
the cycle length cannot only rely on a short fragment of video but a contextual
understanding. The first point is implemented by a coarse-to-fine cycle
refinement method. It avoids the heavy computation of exhaustively searching
all the cycle lengths in the video, and, instead, it propagates the coarse
prediction for further refinement in a hierarchical manner. We secondly propose
a bidirectional cycle length estimation method for a context-aware prediction.
It is a regression network that takes two consecutive coarse cycles as input,
and predicts the locations of the previous and next repetitive cycles. To
benefit the training and evaluation of temporal repetition counting area, we
construct a new and largest benchmark, which contains 526 videos with diverse
repetitive actions. Extensive experiments show that the proposed network
trained on a single dataset outperforms state-of-the-art methods on several
benchmarks, indicating that the proposed framework is general enough to capture
repetition patterns across domains.Comment: Accepted by CVPR202
Utilization of LNG Cryogenic Energy in a Proposed Method for Inlet Air Cooling to Improve the Performance of a Combined Cycle
AbstractIn this study a cold production process was proposed for inlet air cooling in which cryogenic energy from liquefied natural gas (LNG) was sufficiently converted to cold energy. The effect of using the cold production process for inlet air cooling on the off-design performance of a gas turbine combined cycle was analyzed under different ambient conditions. The cold output of the proposed process was increased by about 38.1% to 42.5% compared to that of the conventional cold production process that involves direct LNG evaporation. Furthermore for the inlet air cooling, the proposed method increased the relative power increment from 2.2% to 14.4% and the relative efficiency increment from 0.7% to 2.2%, mainly depending on the variations in the relative humidity, compared to cold production without air cooling. The relative power and relative efficiency of the proposed air cooling were increased by 0.6% to 3.1% and 0.3% to 0.5%, respectively, above those of the traditional air cooling
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