Discoid Bicelles as Efficient Templates for Pillared Lamellar Periodic Mesoporous Silicas at pH 7 and Ultrafast Reaction Times

We report the first synthesis of periodic mesoporous silicas templated by bicelles. The obtained materials form novel pillared lamellar structures with a high degree of periodic order, narrow pore size distributions, and exceptionally high surface areas.     

Human Activity Classification Using On-Body Miniaturized Antennas

Wireless Personal Communications - In this paper, a D2D multiple-metric routing protocol is proposed in the situation that the network infrastructures are ruined due to a possible natural disaster....     

An update technology for integrated biomass gasification combined cycle power plant

A discussion is presented on the technical analysis of a 6.4 MW_e integrated biomass gasification combined cycle (IBGCC) plant. It features three numbers of downdraft biomass gasifier systems with suitable gas clean-up trains, three numbers of internal combustion (IC) producer gas engines for producing 5.85 MW electrical power in open cycle and 550 kW power in a bottoming cycle using waste heat. Comparing with IC gas engine single cycle systems, this technology route increases overall system efficiency of the power plant, which in turn improves plant economics. Estimated generation cost of electricity indicates that mega-watt scale IBGCC power plants can contribute to good economies of scale in India. This paper also highlight’s the possibility of activated carbon generation from the char, a byproduct of gasification process, and use of engine’s jacket water heat to generate chilled water through VAM for gas conditioning.     

Cryogenic tilt table

We describe the design and development of a cryogenic tilt table that will be used to test the flight hardware for NASA’s Satellite Test of the Equivalence Principle (STEP). Our table can tilt the hardware around two axes and is part of a test bed that has 6-degree-of-freedom controllability. The goal was to build a tilt table with a resolution better than ∼5 μrad (1 arcsec). Our table consists of three aluminum plates. The outermost plate is attached to the cryogenic probe and is fixed. The middle and inner plates rest on the outer and middle plates, respectively, using knife edges and knife edge holders made of silicon nitride that are glued to the aluminum plates. A cryogenic tilt sensor was also developed and integrated with the table. The sensor consists of an electrically grounded copper cube hanging from a support, and is placed between two pairs of capacitive electrodes. Any motion of the cube caused by tilting is measured differentially using a Wheatstone bridge circuit. The table is connected to the bottom of a cryogenic probe. A voice coil actuator, located on top of the probe at room temperature, is used to create the necessary tilt. A thin fiber is used to connect the actuator and the table. The system is controlled using a dSPACE control card. A test of the table at cryogenic temperatures (4.5 K) and low pressure (1 μTorr) showed a noise level of ∼0.7 μrad (150 marcsec), which is nearly an order of magnitude better than the required resolution.     

Discoid Bicelles as Efficient Templates for Pillared Lamellar Periodic Mesoporous Silicas at pH 7 and Ultrafast Reaction Times

We report the first synthesis of periodic mesoporous silicas templated by bicelles. The obtained materials form novel pillared lamellar structures with a high degree of periodic order, narrow pore size distributions, and exceptionally high surface areas.     

Distributed optimal control in a nuclear reactor†

The linear deterministic mathematical model of a nuclear reactor system, which can bo described by parabolic partial differential equations, and the problems associated with this model arc discussed in this paper. Also studied is the derivation of a maximum principle for this distributed nuclear reactor system and the problems associated with approximating this distributed system by discretization into a lumped system. Examples concerning the regulator and the servomechanism problems of a nuclear reactor system are presented.     

Interval Duration Logic: Expressiveness and Decidability

We investigate a variant of dense-time Duration Calculus which permits model checking using timed/hybrid automata. We define a variant of the Duration Calculus, called Interval Duration Logic, (IDL), whose models are timed state sequences [1].A subset LIDL of IDL consisting only of located time constraints is presented. As our main result, we show that the models of an LIDL formula can be captured as timed state sequences accepted by an event-recording integrator automaton. A tool called IDLVALID for reducing LIDL formulae to integrator automata is briefly described. Finally, it is shown that LIDL has precisely the expressive power of event-recording integrator automata, and that a further subset LIDL- corresponds exactly to event-recording timed automata [2]. This gives us an automata-theoretic decision procedure for the satisfiability of LIDL– formulae.     

Crystallization Kinetics and Mechanism of Low-Expansion Lithium Aluminosilicate Glass-Ceramics by Dilatometry

The crystallization kinetics and mechanism of a precursor glass of lithium aluminosilicate (LAS)-based commercial low-expansion glass-ceramics were investigated using a dilatometer. The isothermal crystallization behavior of β-quartz solid solution (ss) was found to obey the Avrami equation. Nonisothermal crystallization data were analyzed by the Ozawa method and modified Kissinger equation. The value of the Avrami exponent ( n ) was ∼1.5, and the apparent activation energy ( E _a) was ∼500 kJ/mol, which was close to that of the diffusion of silicon and aluminum ions as well as metal–oxygen bond strengths, suggesting a three-dimensional (3D) diffusion-controlled reaction mechanism.