A near-field scanning microwave microscope for characterization of inhomogeneous photovoltaics

We present a near-field scanning microwave microscope (NSMM) that has been configured for imaging photovoltaic samples. Our system incorporates a Pt-Ir tip inserted into an open-ended coaxial cable to form a weakly coupled resonator, allowing the microwave reflection S(11) signal to be measured across a sample over a frequency range of 1 GHz - 5 GHz. A phase-tuning circuit increased impedance-measurement sensitivity by allowing for tuning of the S(11) minimum down to -78 dBm. A bias-T and preamplifier enabled simultaneous, non-contact measurement of the DC tip-sample current, and a tuning fork feedback system provided simultaneous topographic data. Light-free tuning fork feedback provided characterization of photovoltaic samples both in the dark and under illumination at 405 nm. NSMM measurements were obtained on an inhomogeneous, third-generation Cu(In,Ga)Se(2) (CIGS) sample. The S(11) and DC current features were found to spatially broaden around grain boundaries with the sample under illumination. The broadening is attributed to optically generated charge that becomes trapped and changes the local depletion of the grain boundaries, thereby modifying the local capacitance. Imaging provided by the NSMM offers a new RF methodology to resolve and characterize nanoscale electrical features in photovoltaic materials and devices.     

Identification of 1’,5’-naphthyridinophthalone and its quantification in the color additive D&C Yellow No. 10 (Quinoline Yellow) using high-performance liquid chromatography

The present work reports the identification and characterization of a contaminant, 2-(2?-(1,5-naphthyridinyl))-1,3-indanedione (1?,5?-naphthyridinophthalone, 1,5NP), in the color additive D&;C Yellow No. 10 (U.S.-certifiable form of Quinoline Yellow), together with its quantification in batches of the color additive certified by the U.S. Food and Drug Administration (USFDA). The impurity, which is a compound not previously reported in the literature, was synthesised and characterised for use as a reference material. Test portions from 26 certified batches of D&;C Yellow No. 10 submitted to USFDA by four domestic and four foreign manufacturers were analyzed for 1,5NP using high-performance liquid chromatography. The results revealed a wide range of 1,5NP levels across batches, with 18 (69.2%) of the test portions containing amounts from 0.32 to 169.94 µg g^?1 while the remaining test portions contained no detectable (<0.07 µg g^?1) amounts. Samples of the European and Japanese forms of Quinoline Yellow were also analyzed and found to contain a wide range of 1,5NP levels. The varying levels of 1,5NP in all three forms of Quinoline Yellow suggest that contamination can be significantly decreased or eliminated through manufacturing adjustments. Since 1,5NP is closely related to a D&;C Yellow No. 10 contaminant (quinophthalone) that has a USFDA-specified limit of 4 µg g^?1 and is a known allergen, assessment of the possible allergenicity of 1,5NP is warranted.     

US states and energy efficiency: North Carolina's ‘quango’

This paper argues that energy efficiency remains an abstraction until actions produce significant results in the ways in which energy is produced and used. In the USA, such actions have depended historically on the private sector, with government taking an increasingly prominent role since the first energy crisis of the 1970s. Experience has shown that neither acting alone has been fully successful at realizing the economically and societally rational rate of implementation made possible by either the needs or the opportunities in energy. Recent developments in various states have begun to explore hybrid organizations - quasi-public and quasi-private - as ways to focus resources in productive applications. Four examples merit attention, with particular emphasis on the North Carolina Alternative Energy Corporation.     

Compatibility between cotherapists: An empirical report.

Investigated factors contributing to perceived compatibility of 42 cotherapists participating in 24 cotherapy pairs. Measures indicated that cotherapists felt compatible with their partners, but their scores did not correlate significantly with those of their supervisors. Cotherapy pairs in which Ss described themselves similarly with respect to self-disclosure and directiveness were more likely to experience themselves as compatible. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Use of Precirol® to Prepare Sustained Release Tablets of Theophylline and Quinidine Gluconate

Tablets were made using theophylline, lactose and Precirol by a granulation technique, resulting in more than 12 hours release. Granulation and hot fusion methods were used to prepare admixtures of quinidine gluconate and Precirol at different ratios of Precirol: drug, 1:9, 3:7 and 1:1. Dissolution studies in 0.1N HCl showed drastic differences in the release of quinidine gluconate from tablets made by the two different methods; granulation method gave a faster release while the hot fusion method gave slower and incomplete release at higher Precirol content. The release rate decreases with higher Precirol content.     

Engineering Economy and the Two Rates of Return—Mixed Mode Computations

This paper describes research on the reformulation of the methods of engineering economics to include the effects of inflation. Starting with a rather common and rational approximation of inflation effects, the paper shows that there are actually two rates of return. The paper also shows that fundamental techniques of engineering economics can be readily adapted to this redefinition and that recognition of the two rates can lead to significantly improved sensitivity analyses.     

Adaptation level, personality theory, and psychopathology.

Adaptation-level (AL) theory represents a quantitative approach to the concept of adjustment and offers an experimental psychological point of departure for a science of personal and social behavior. It is suggested that a personality theory develop from classification of response types specifying relevant aspects of the focal, background, and residual factors. The various psychopathologies may be similarly viewed in terms of specific behavioral excesses or impairments within the framework of AL theory. A proposal for the use of AL theory in regard to personality and psychopathology is outlined and representative studies are cited. (58 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)