Flowfield Analysis of a Pneumatic Solenoid Valve

Pneumatic solenoid valve has been widely used in the vehicle control systems for meeting the rapid-reaction demand triggered by the dynamic conditions encountered during the driving course of vehicle. For ensuring the safety of human being, the reliable and effective solenoid valve is in great demand to shorten the reaction time and thus becomes the topic of this research. This numerical study chooses a commercial 3/2-way solenoid valve as the reference valve for analysing its performance. At first, CFD software Fluent is adopted to simulate the flow field associated with the valve configuration. Then, the comprehensive flow visualization is implemented to identify the locations of adverse flow patterns. Accordingly, it is found that a high-pressure region exists in the zone between the nozzle exit and the top of iron core. Thereafter, the nozzle diameter and the distance between nozzle and spool are identified as the important design parameters for improving the pressure response characteristics of valve. In conclusion, this work establishes a rigorous and systematic CFD scheme to evaluate the performance of pneumatic solenoid valve

Flowfield Analysis of a Pneumatic Solenoid Valve

Pneumatic solenoid valve has been widely used in the vehicle control systems for meeting the rapid-reaction demand triggered by the dynamic conditions encountered during the driving course of vehicle. For ensuring the safety of human being, the reliable and effective solenoid valve is in great demand to shorten the reaction time and thus becomes the topic of this research. This numerical study chooses a commercial 3/2-way solenoid valve as the reference valve for analysing its performance. At first, CFD software Fluent is adopted to simulate the flow field associated with the valve configuration. Then, the comprehensive flow visualization is implemented to identify the locations of adverse flow patterns. Accordingly, it is found that a high-pressure region exists in the zone between the nozzle exit and the top of iron core. Thereafter, the nozzle diameter and the distance between nozzle and spool are identified as the important design parameters for improving the pressure response characteristics of valve. In conclusion, this work establishes a rigorous and systematic CFD scheme to evaluate the performance of pneumatic solenoid valve

Climate-mediated cooperation promotes niche expansion in burying beetles

The ability to form cooperative societies may explain why humans and social insects have come to dominate the earth. Here we examine the ecological consequences of cooperation by quantifying the fitness of cooperative (large groups) and non-cooperative (small groups) phenotypes in burying beetles (Nicrophorus nepalensis) along an elevational and temperature gradient. We experimentally created large and small groups along the gradient and manipulated interspecific competition with flies by heating carcasses. We show that cooperative groups performed as thermal generalists with similarly high breeding success at all temperatures and elevations, whereas non-cooperative groups performed as thermal specialists with higher breeding success only at intermediate temperatures and elevations. Studying the ecological consequences of cooperation may not only help us to understand why so many species of social insects have conquered the earth, but also to determine how climate change will affect the success of these and other social species, including our own

Flowfield Analysis of a Pneumatic Solenoid Valve

Pneumatic solenoid valve has been widely used in the vehicle control systems for meeting the rapid-reaction demand triggered by the dynamic conditions encountered during the driving course of vehicle. For ensuring the safety of human being, the reliable and effective solenoid valve is in great demand to shorten the reaction time and thus becomes the topic of this research. This numerical study chooses a commercial 3/2-way solenoid valve as the reference valve for analysing its performance. At first, CFD software Fluent is adopted to simulate the flow field associated with the valve configuration. Then, the comprehensive flow visualization is implemented to identify the locations of adverse flow patterns. Accordingly, it is found that a high-pressure region exists in the zone between the nozzle exit and the top of iron core. Thereafter, the nozzle diameter and the distance between nozzle and spool are identified as the important design parameters for improving the pressure response characteristics of valve. In conclusion, this work establishes a rigorous and systematic CFD scheme to evaluate the performance of pneumatic solenoid valve

Climate-mediated cooperation promotes niche expansion in burying beetles

The ability to form cooperative societies may explain why humans and social insects have come to dominate the earth. Here we examine the ecological consequences of cooperation by quantifying the fitness of cooperative (large groups) and non-cooperative (small groups) phenotypes in burying beetles (Nicrophorus nepalensis) along an elevational and temperature gradient. We experimentally created large and small groups along the gradient and manipulated interspecific competition with flies by heating carcasses. We show that cooperative groups performed as thermal generalists with similarly high breeding success at all temperatures and elevations, whereas non-cooperative groups performed as thermal specialists with higher breeding success only at intermediate temperatures and elevations. Studying the ecological consequences of cooperation may not only help us to understand why so many species of social insects have conquered the earth, but also to determine how climate change will affect the success of these and other social species, including our own

Multiple Patterns of Regulation and Overexpression of a Ribonuclease-Like Pathogenesis-Related Protein Gene, <i>OsPR10a</i>, Conferring Disease Resistance in Rice and <i>Arabidopsis</i>

<div><p>An abundant 17 kDa RNase, encoded by <i>OsPR10a</i> (also known as PBZ1), was purified from P_i-starved rice suspension-cultured cells. Biochemical analysis showed that the range of optimal temperature for its RNase activity was 40–70°C and the optimum pH was 5.0. Disulfide bond formation and divalent metal ion Mg²⁺ were required for the RNase activity. The expression of <i>OsPR10a</i>::<i>GUS</i> in transgenic rice was induced upon phosphate (P_i) starvation, wounding, infection by the pathogen <i>Xanthomonas oryzae</i> pv. <i>oryzae</i> (<i>Xoo</i>), leaf senescence, anther, style, the style-ovary junction, germinating embryo and shoot. We also provide first evidence in whole-plant system, demonstrated that <i>OsPR10a</i>-overexpressing in rice and <i>Arabidopsis</i> conferred significant level of enhanced resistance to infection by the pathogen <i>Xoo</i> and <i>Xanthomona campestris</i> pv. <i>campestris</i> (<i>Xcc</i>), respectively. Transgenic rice and <i>Arabidopsis</i> overexpressing <i>OsPR10a</i> significantly increased the length of primary root under phosphate deficiency (-P_i) condition. These results showed that <i>OsPR10a</i> might play multiple roles in phosphate recycling in phosphate-starved cells and senescing leaves, and could improve resistance to pathogen infection and/or against chewing insect pests. It is possible that P_i acquisition or homeostasis is associated with plant disease resistance. Our findings suggest that gene regulation of <i>OsPR10a</i> could act as a good model system to unravel the mechanisms behind the correlation between P_i starvation and plant-pathogen interactions, and also provides a potential application in crops disease resistance.</p></div

Phenotypes of WT and the <i>OsPR10a</i>-overexpressing transgenic seedlings under +P_i and –P_i conditions.

<p>Rice seeds were imbibed in distilled water for 3 days, germinating embryos were isolated and placed onto the vertical plates containing solid half-strength of MS medium supplemented with or without P_i. (A) and (B) Isolated embryos incubated either in +P_i medium (A) or–P_i medium (B) for another 6 days were photographed. Bars = 1 cm. (C) and (E) Quantitative analyses of shoot lengths (C) and primary roots (E) of seedlings cultured in +P_i medium. (D) and (F) Quantitative analyses of shoot lengths (D) and primary roots (F) of seedlings cultured in -P_i medium. Groups that do not share the same letter are significantly different estimated by ANOVA (P <0.05). Data are shown as means ±SD (n = 10).</p

Phosphate starvation induced <i>OsPR10a</i> gene expression in rice suspension-cultured cells.

<p>Rice suspension cells were cultured in MS medium for 3 days and transferred to MS medium supplemented with (+P_i) or without (-P_i) phosphate. Total RNA was isolated from cells and subjected to northern blot analysis using the <i>OsPR10a</i> coding region as a probe. The rRNA served as a total RNA loading control.</p

Agarose gel electrophoresis of enzymatic hydrolysates of yeast tRNA by the purified 17 kDa protein.

<p>A total of 0.5 μg of purified 17 kDa protein was mixed with or without 1.0 μg of rice genomic DNA (DNA) or 5.0 μg of yeast t-RNA (tRNA). The mixtures were incubated for the indicated times followed by 1.5% agarose gel electrophoresis.</p