Theoretical concentration of solar radiation by central receiver systems

Solar concentrations by central receiver systems have been calculated theoretically for various values of obliquity of the incident radiation, assuming that plane heliostat-mirrors, sufficiently small in dimension, cover a circular field without clearance. Through this calculation, the performance characteristics of this system such as the availability of the radiant energy incident on the heliostat-field, the distribution of interruption by an adjacent mirror, the optimum rim-angle for the mean area- and the mean volume-concentration and the attainable temperature were revealed. The study was extended towards the practical problem of decreasing the number of heliostats by increasing the dimensions of heliostat-mirrors, and the effect of increasing mirror-dimensions was argued for both plane and curved mirrors.     

Gel permeation chromatography using controlled-porosity glass. II. Polyacrylamide aqueous solutions

In a study of polyacrylamide in solutions we have required the rapid characterization on chromatographies. The application to the aqueous solution of the GPC using controlled-porosity glass has been examined from both the viewpoint of the effect of salt addition and the GPC mechanism. An adequate addition to neutral salt, 0.005M KCI to the eluent, gave rise to the elution behaviors being in accord with the hydrodynamic volume concept of the GPC separation.     

Effects of atmospheric ozone on microarray data quality

A data anomaly was observed that affected the uniformity and reproducibility of fluorescent signal across DNA microarrays. Results from experimental sets designed to identify potential causes (from microarray production to array scanning) indicated that the anomaly was linked to a batch process; further work allowed us to localize the effect to the posthybridization array stringency washes. Ozone levels were monitored and highly correlated with the batch effect. Controlled exposures of microarrays to ozone confirmed this factor as the root cause, and we present data that show susceptibility of a class of cyanine dyes (e.g., Cy5, Alexa 647) to ozone levels as low as 5-10 ppb for periods as short as 10-30 s. Other cyanine dyes (e.g., Cy3, Alexa 555) were not significantly affected until higher ozone levels (> 100 ppb). To address this environmental effect, laboratory ozone levels should be kept below 2 ppb (e.g., with filters in HVAC) to achieve high quality microarray data.     

Development of silicon wafer packaging technology for deep UV LED

This paper reports a deep‐ultraviolet LED (deep‐UV‐LED) package based on silicon MEMS process technology (Si‐PKG). The package consists of a cavity formed by silicon crystalline anisotropic etching, through‐silicon vias (TSVs) filled with electroplated Cu, bonding metals made of electroplated Ni/AuSn and a quartz lid for hermetic sealing. A deep‐UV LED die is directly mounted in the Si‐PKG by AuSn eutectic bonding without a submount. It has advantages in terms of size, heat dissipation, light utilization efficiency, productivity and cost over conventional AlN ceramic packages. We confirmed a light output of 30 mW and effective reflection on Si (111) cavity slopes in the Si‐PKG. Based on simulation, further improvement of the optical output is expected by optimizing DUV‐LED die mount condition.     

Thick films for multilayer substrates

Abstract

Low temperature fired ceramics based on alumina/glass added oxide ceramics have been developed and are being used by several companies as substrates for high density assembled modular packaging.^1–3 The features of low temperature fireable substrates are the cofireability with highly conductive metals such as Ag, Ag-Pd, or Cu, and the cofireability with other passive component materials for L, C, R and relatively low dielectric constant elements. But most of these substrates have the disadvantage that their thermal expansion coefficient is not perfectly compatible with Si or GaAs. This paper reports the results of a newly developed cordierite/glass based substrate employing Cu as the surface and internal conductors and having the freedom of tuning the thermal expansion coefficient by changing the composition. The ceramic composition with adjustable thermal expansion coefficient value of 3 to 7 ppm/°C can be manufactured and easily matched with the thermal expansion coefficient of Si or GaAs without a big change of electrical performance.     

The Role of Cytokines Produced via the NLRP3 Inflammasome in Mouse Macrophages Stimulated with Dental Calculus in Osteoclastogenesis

Dental calculus (DC) is a common deposit in periodontitis patients. We have previously shown that DC contains both microbial components and calcium phosphate crystals that induce an osteoclastogenic cytokine IL-1β via the NLRP3 inflammasome in macrophages. In this study, we examined the effects of cytokines produced by mouse macrophages stimulated with DC on osteoclastogenesis. The culture supernatants from wild-type (WT) mouse macrophages stimulated with DC accelerated osteoclastogenesis in RANKL-primed mouse bone marrow macrophages (BMMs), but inhibited osteoclastogenesis in RANKL-primed RAW-D cells. WT, but not NLRP3-deficient, mouse macrophages stimulated with DC produced IL-1β and IL-18 in a dose-dependent manner, indicating the NLRP3 inflammasome-dependent production of IL-1β and IL-18. Both WT and NLRP3-deficient mouse macrophages stimulated with DC produced IL-10, indicating the NLRP3 inflammasome-independent production of IL-10. Recombinant IL-1β accelerated osteoclastogenesis in both RANKL-primed BMMs and RAW-D cells, whereas recombinant IL-18 and IL-10 inhibited osteoclastogenesis. These results indicate that DC induces osteoclastogenic IL-1β in an NLRP3 inflammasome-dependent manner and anti-osteogenic IL-18 and IL-10 dependently and independently of the NLRP3 inflammasome, respectively. DC may promote alveolar bone resorption via IL-1β induction in periodontitis patients, but suppress resorption via IL-18 and IL-10 induction in some circumstances.     

Density-Functional Theoretical Study on the Role of Lewis and Brønsted Acid Sites on CeO2(110) Surfaces for Nitrile Hydration

Hydration of cyanopyridine on CeO₂(110) surfaces was studied using periodic DFT+U calculations. One of two adsorption modes of 2-cyanopyridine occurs with two-point interaction which causes substrate specificity. A catalytic cycle for the hydration of 2-cyanopyridine was proposed. Cooperativity of Lewis and Brønsted acid sites was found to stabilize the intermediates for the hydration.     

Pancyclicity of recursive circulant graphs

In this paper, we study the existence of cycles of all lengths in the recursive circulant graphs, and we show a necessary and sufficient condition for the graph being pancyclic and bipancyclic.