Operability of a thermally driven magnesium oxide/water chemical heat pump

The operability of a thermally driven chemical heat pump using the magnesium oxide/water reaction system was demonstrated experimentally. The heat pump system, consisting of a packed bed reactor and a water reservoir, was operated thermally with no mechanical work. The thermal output performance of the reactor bed was measured under pressures between SO and 202 kPa. The heat pump was expected to be applicable as a heat storage system for high efficiency energy utilization in cogeneration.     

Effect of diluents on membrane formation via thermally induced phase separation

The effect of diluents on isotactic polypropylene (iPP) membrane formation via thermally induced phase separation was investigated. The diluents were methyl salicylate (MS), diphenyl ether (DPE), and diphenylmethane (DPM). The cloud-point curve was shifted to a lower temperature in the order iPP–MS, iPP–DPE, and iPP–DPM, whereas the crystallization temperature was not influenced so much by diluent type. Droplet-growth processes were investigated under two conditions: quenching the polymer solution at the desired temperature and cooling at a constant rate. Although droplet sizes were in the order iPP–MS, iPP–DPE, and iPP–DPM in both cases, the difference was more pronounced with the constant cooling rate condition. Scanning electron microscopy indicated that interconnected structures were obtained when the polymer solution was quenched in ice water. The effect of the diluents on these structures was observed. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 169–177, 2001     

Synthesis of nickel nanoparticles with excellent thermal stability in micropores of zeolite

Nickel (Ni) nanoparticles were synthesized in micropores of zeolite by the adsorption and decomposition of a sublimated Ni organometallic compound, Ni(C₅H₅)₂, to invent metallic catalysts with nanosize, which are smaller than 5 nm and keep the nanosize at high temperature. In the decomposition process, Ni species were partially decomposed by ultraviolet light irradiation and fixed in zeolite pores prior to thermal reduction under H₂ flow. Note that the Ni nanoparticles showed an excellent thermal stability, because they kept the high dispersion with diameters smaller than 5 nm even after heating at 400 °C. On the other hand, the Ni particles supported on zeolite by a conventional method, which is an incipient wetness impregnation process, became larger than 10 nm after heating at the same temperature. The synthesized Ni nanoparticles acted as a metallic catalyst because they showed higher selectivity for H₂ generation than C₂H₄ generation during ethanol steam reforming reaction.     

Holdup and flow pattern of solid particles in freeboard of gas—solid fluidized bed with fine particles

The behavior of solid particles suspended in the freeboard of a 12 cm i.d. fluidized bed was studied using FCC particles of which the weight-mean diameter was 65 – 68 μm. The height of the freeboard was 180 cm, and the superficial gas velocity was changed from 15 to 50 cm s^?1.The weight-mean diameter and holdup of solid particles in the freeboard below the TDH vary with the axial position and the gas velocity. The lateral distribution of the solids holdup measured by a capacitance probe is almost flat in the region of r ? 5 cm, but the relative pulse frequency detected by a fiber optic probe indicates that the solids holdup increases greatly in the immediate vicinity of the column wall. The flow patterns of solid particles were measured by a fiber optic probe and a thermal response probe. The steady internal circulation of solid particles is formed in the freeboard below the TDH, and the circulating solids flow rate is much larger than the net entrainment rate of solid particles.     

Shear‐Induced Fabrication of Multiple Parallel Alginate Gel Filaments Using Alginate–Polyethylene Glycol Blend

A rigid assembly of alginates is formed in aqueous media primarily via hydrogen bonding between guluronic units. A flow of aqueous alginate solution in a co‐flow capillary can form alginate gel fibers by contact with Ca²⁺ ions in sheath flow. Mixing with polyols [e.g., polyethylene glycol (PEG)] facilitates the shaping of the alginate assembly because PEG disrupts the assembly of the extended alginate chains to instead form alginate–PEG complexes that exhibit shear‐thinning behavior. The shear‐induced fibrous domains of the globular alginate–PEG complexes can be partitioned by a PEG‐rich phase, resulting in multiple parallel alginate gel filaments when the strong ionic‐field‐induced PEG‐rich phase is adjusted and an alginate–PEG complex phase is used as the aqueous two‐phase separation system.     

Touch fault calculation method on transmission lines stringing on the same tower based on symmetrical coordinate method

In this paper, a touch fault calculation method is proposed based on the symmetric coordinate method. The touch fault in this paper means that a line‐to‐line short circuit fault occurred on parallel transmission lines stringing on a same tower. It is known that the touch fault occurs very rarely such as the galloping phenomena, and it causes an abnormal voltage rise especially on a low‐voltage transmission line. However, a quantitative analysis method of the abnormal voltage has not been proposed. Therefore, a general analysis method of the voltage profile solution for the touch fault is proposed based on the symmetrical coordinate method. The proposed method is able to calculate the precise voltage and current profile solution efficiently by introducing the similar formation for the touch fault solution same as the general fault solution. Demonstrative result to the application in the touch fault calculation is presented in order to verify the practicability of the proposed method.     

Liquid‐Crystalline Electrolytes for Lithium‐Ion Batteries: Ordered Assemblies of a Mesogen‐Containing Carbonate and a Lithium Salt

Thermotropic liquid‐crystalline (LC) electrolytes for lithium‐ion batteries are developed for the first time. A rod‐like LC molecule having a cyclic carbonate moiety is used to form self‐assembled two‐dimensional ion‐conductive pathways with lithium salts. Electrochemical and thermal stability, and efficient ionic conduction is achieved for the liquid crystal. The mixture of the carbonate derivative and lithium bis(trifluoromethylsulfonyl)imide is successfully applied as an electrolyte in lithium‐ion batteries. Reversible charge–discharge for both positive and negative electrodes is observed for the lithium‐ion batteries composed of the LC electrolyte.     

Plastic module of laser diode and photodiode mounted on planarlightwave circuit for access network

Low-cost plastic packaging of laser diodes and photodiodes mounted on planar lightwave circuit (PLC) platform are developed and its reliability is confirmed under various environmental and endurance tests. The high performance of the module is maintained under reliability tests, such as high-humidity high-temperature tests (85°C, 85%RH) and temperature cycling tests (-40°C/85°C). No laser diodes show any device characteristics change during environmental tests and their stability has very little dependence on current bias. Although the photodiodes show an increase in leakage current under high-temperature high-humidity tests and the rate of leakage current increase is proportional to the square root of bias voltage, the increase is negligible for system use. These plastic modules can be applied to actual access networks and other fiber-optic networks     

Gateway Selection Protocol in Hybrid MANET Using DYMO Routing

In this paper, we propose a novel gateway (GW) selection protocol in hybrid Mobile Ad hoc Networks (MANETs). We focus on the situation that occurs when specialized, sensitive data is sent to the Internet from MANET nodes. These special data types are especially susceptible to security risks such as information leak and data falsification. Therefore, it is necessary for such special data to be forwarded by a secure/trusted GW which is controlled by a trusted network administrator. However, there should be multiple GWs deployed in a MANET, where the cost ineffectiveness makes it difficult for a network administrator to simultaneously manage every GW. Because of the risk of forwarding special data through an unmaintained GW, we propose a routing protocol which allows a source node to have sensitive data forwarded to the Internet through a trusted GW. To achieve this desirable performance, we improve upon one of the newest routing protocols, Dynamic MANET On-demand (DYMO), which works in consideration of application data. Through simulations, we evaluate our protocol in comparison with the conventional DYMO protocol. The results show that our protocol can make MANET source nodes choose GWs for specific data.