Peer relations among adolescents with female same-sex parents.

This study examined associations among family type (same-sex vs. opposite-sex parents), adolescent gender, family and relationship variables, and the peer relations of adolescents. Participants included 44 adolescents parented by same-sex female couples and 44 adolescents parented by opposite-sex couples, matched on demographic characteristics and drawn from a national sample. On both self-reported and peer-reported measures of relations with peers, adolescents were functioning well, and the quality of their peer relations was not associated with family type. Regardless of family type, adolescents whose parents described closer relationships with them reported higher quality peer relations and more friends in school and were rated as more central in their friendship networks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Demonstration of a micro-fabricated hydrogen storage module for micro-power systems

The objective of this work was to demonstrate a micro-fabricated hydrogen storage module for micro-power systems. Hydrogen storage materials were developed as thin-film inks to be compatible with an integrated manufacturing process. Performance and durability of storage modules were evaluated. Further, applications were demonstrated for a nickel-hydrogen battery and a micro-fabricated hydrogen-air PEM fuel cell. The ink making process, in which polymer binders and solvents were added to the palladium-treated alloys, slightly decreased the storage capacities, but had little effect on the activation properties of the treated alloys. After 5000 absorption/desorption cycles under hydrogen, the hydrogen storage capacities of the thin-film inks remained high. Absorption/desorption behavior of the ink was tested in the environment of a new type nickel-hydrogen battery, in which it would in contact with 26 wt% KOH solution, and the ink showed no apparent degradation. Storage modules were successfully used as the hydrogen source for PEM fuel cell.     

A three-dimensional numerical simulation of the transport phenomena in the cathodic side of a PEMFC

A three-dimensional numerical model is developed to simulate the transport phenomena on the cathodic side of a polymer electrolyte membrane fuel cell (PEMFC) that is in contact with parallel and interdigitated gas distributors. The computational domain consists of a flow channel together with a gas diffusion layer on the cathode of a PEMFC. The effective diffusivities according to the Bruggman correlation and Darcy's law for porous media are used for the gas diffusion layer. In addition, the Tafel equation is used to describe the oxygen reduction reaction (ORR) on the catalyst layer surface. Three-dimensional transport equations for the channel flow and the gas diffusion layer are solved numerically using a finite-volume-based numerical technique. The nature of the multi-dimensional transport in the cathode side of a PEMFC is illustrated by the fluid flow, mass fraction and current density distribution. The interdigitated gas distributor gives a higher average current density on the catalyst layer surface than that with the parallel gas distributor under the same mass flow rate and cathode overpotential. Moreover, the limiting current density increased by 40% by using the interdigitated flow field design instead of the parallel one.     

A Micro-fabricated Hydrogen Storage Module with Sub-atmospheric Activation and Durability in Air Exposure

The objective of this work was to develop a hydrogen storage module for onboard electrical power sources suitable for use in micro-power systems and micro-electro-mechanical systems (MEMS). Hydrogen storage materials were developed as thin-film inks to be compatible with an integrated manufacturing process. Important design aspects were (a) ready activation at sub-atmospheric hydrogen pressure and room temperature and (b) durability, i.e. capable of hundreds of absorption/desorption cycles and resistance to deactivation on exposure to air. Inks with palladium-treated intermetallic hydrogen storage alloys were developed and are shown here to be compatible with a thin-film micro-fabrication process. These hydrogen storage modules absorb hydrogen readily at atmospheric pressure, and the absorption/desorption rates remained fast even after the ink was exposed to air for 47 weeks.     

Delinquency, victimization, and substance use among adolescents with female same-sex parents.

The question of whether parental sexual orientation has an impact on human development has important implications for psychological theories and for legal policy. This study examined associations among family type (same-sex vs. different-sex parents), family and relationship variables, substance use, delinquency, and victimization of adolescents. Participants included 44 adolescents living with female same-sex couples and 44 adolescents living with different-sex couples, matched on demographic characteristics and drawn from a national sample. Analyses indicated that adolescents were functioning well and that their adjustment was not associated with family type. Adolescents whose parents described closer relationships with them reported less delinquent behavior and substance use, suggesting that the quality of parent-adolescent relationships better predicts adolescent outcomes than does family type. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Power generation using a mesoscale fuel cell integrated with a microscale fuel processor

An integrated fuel reformer and fuel cell system for microscale (10–500 mW) power generation is being developed and demonstrated as an alternative to conventional batteries. In this system, thermal energy is transformed to electricity by stripping the hydrogen from the hydrocarbon fuel (reforming) and converting the hydrogen to electricity in a proton exchange membrane (PEM) fuel cell. The fabrication and operation of a mesoscale fuel cell based on phosphoric acid doped polybenzimidazole (PBI) technology is discussed, along with tests integrating the methanol processor with the fuel cell. The PBI membrane had high ionic conductivity at high temperatures (>150 °C), and sustained the high conductivity at low relative humidity at these temperatures. This high-temperature stability and high ionic conductivity enabled the membrane to tolerate extremely high levels of carbon monoxide up to 10% without significant degradation in performance. The combined fuel cell/reformer system was successfully operated to enable the production of 23 mW of electrical power.     

THE CHEMISTRY OF NITROSAMINE FORMATION: RELEVANCE TO MALTING AND BREWING

This paper reviews the chemistry of nitrosamine formation with special reference to malting and brewing. Whilst the main emphasis is on the formation of nitrosodimethylamine (NDMA), the chemistry is also related to the formation of other nitrosamines and certain other nitrocompounds. It seems likely that in malting and brewing the only important source of the nitroso group is the mixture of oxides of nitrogen (NO_x) in the hot air in contact with malt during kilning. Under normal commercial conditions there appears to be little if any formation of nitrosamines at other stages of malting or brewing. It is suggested that much of the nitrosation is due to NO_x which exists temporarily in the form of nitrogen trioxide (N₂O₃) and nitrogen tetroxide (N₂O₄) as it dissolves in water in the moist malt or in malt lipids. The dissolved NO_x subsequently reaches equilibrium with nitrite and nitrate ions formed from it. The origin of the dimethylamine portion of the NDMA is still not clear. The most likely sources are free DMA, gramine and hordenine, all of which are produced in germinating barley. On balance it seems that hordenine is the most important source of NDMA in the malt at the end of kilning. The reasons for the low yield of nitrosamines from the precursors and NO_x present during kilning are discussed and related to the formation of other nitroso- and nitro-compounds. The occurrence of competing reactions which reduce nitrosamine formation is also described.     

A direct methanol fuel cell using acid-doped polybenzimidazole as polymer electrolyte

A direct methanol/oxygen solid polymer electrolyte fuel cell was demonstrated. This fuel cell employed a 4 mg cm^–2 Pt-Ru alloy electrode as an anode, a 4 mg cm^–2 Pt black electrode as a cathode and an acid-doped polybenzimidazole membrane as the solid polymer electrolyte. The fuel cell is designed to operate at elevated temperature (200°C) to enhance the reaction kinetics and depress the electrode poisoning, and reduce the methanol crossover. This fuel cell demonstrated a maximum power density about 0.1 W cm^–2 in the current density range of 275–500 mA cm^–2 at 200°C with atmospheric pressure feed of methanol/water mixture and oxygen. Generally, increasing operating temperature and water/methanol mole ratio improves cell performance mainly due to the decrease of the methanol crossover. Using air instead of the pure oxygen results in approximately 120 mV voltage loss within the current density range of 200–400 mA cm^–2 .     

Improved durability of hydrogen storage alloys

An effective and durable hydrogen storage module was required to fuel micro-power systems. Two primary specifications for the hydrogen fuel module in this application were a high volumic storage capacity and rapid hydrogen storage and release under atmospheric pressure or lower at room temperature. In addition, the hydrogen module should be operable for thousands of cycles with fast hydriding and dehydriding rates and be resistant to deactivation on exposure to air for many months and longer. In our prior work, mechanical grinding a small amount of palladium with the hydrogen storage alloys was shown to greatly improve the hydrogen storage performance. The palladium treatment of three intermetallic alloys, AB₅ type LaNi_4.7Al_0.3 and CaNi₅, and A₂B type Mg₂Ni, lowered the activation pressure to sub-atmospheric pressure at room temperature and also significantly increased the hydrogen absorption and desorption rates. This work focused on the durability of hydrogen absorption and desorption performances after exposure of the storage materials to air. The palladium treated hydrogen storage alloys retained both low activation pressures and fast absorption and desorption rates even after more than 2 years air exposure.     

A microfabricated nickel–hydrogen battery using thick film printing techniques

To utilize the distinctive cycle life and safety characteristics of the nickel–hydrogen chemistry while eliminating the high pressure limitations of conventional nickel–hydrogen cells, a microfabricated nickel–hydrogen battery using a low-pressure metal hydride for hydrogen storage is being developed for powering micro-electromechanical systems (MEMS) devices and for biomedical applications where the battery would be implanted within the body. Thick film printing techniques which are simple and low cost were used to fabricate this battery. Inks were developed for each of the different battery components, including the electrodes, current collectors and separator. SEM images on these printed components showed the desired characteristics for each. Positive electrode cycling tests were performed on the printed positive electrodes while cyclic voltammetry was used to characterize the printed negative electrodes. Consistent charge and discharge performance was observed during positive electrode cycling. Full cells with printed positive and negative assemblies were assembled and tested.