Neue Vorvakuumpumpe: Schnelles Evakuieren dank Membran‐ Stabilisierungssystem. New roughing pump: Fast Evacuation thanks to Diaphragm Stabilization System

Diaphragm pumps are used at turbomolecular pumps to generate rough vacuum. They are characterized by high suction speed, which however deteriorate when the working pressure decreases. This is caused by the difference between the working pressure of the pump and the ambient pressure. The larger the pressure difference, the more the elastic diaphragm bulges, lowering the effective input volume of the pump. This problem is alleviated by a newly developed diaphragm stabilization system. Diaphragm roughing pumps equipped with this system pump down faster than pumps without the system. Due to the enhanced suction speed, they also ensure greater process reliability. The first application of the diaphragm stabilization system (patent applied for) is in a newly developed diaphragm roughing pump. This pump is driven by a compact, brushless DC motor with very great efficiency. The pump is available in 24‐volt DC and 90‐ to 264‐volt, 50/60‐Hz AC versions. OEM and portable versions are available.     

Lipase-catalyzed synthesis of monoacylglycerides by glycerolysis of campher tree seed oil and cocoa-butter

The lipase-catalyzed glycerolysis of Campher tree seed oil and Cocoa-butter in a solid-phase system was studied. Lipases from Pseudomonas cepacia (PCL) and Chromobacterium viscosum (CVL) were considered as suitable for the synthesis of monoacylglycerols (MAG). The glycerolysis of Campher tree seed oil was performed initially at 25°C followed by cooling to 7°C. This resulted in 86% (PCL) and 90% (CVL) MAG. Maximum concentration of MAG from Cocoa-butter was 89% with both lipases, when the reaction was performed at 25°C. Isolation of MAG was performed by extraction with chloroform at 4°C followed by purification via silica gel chromatography.     

Reusable specification modules for type analysis

Type analysis can be characterized by a language‐independent collection of standard computational roles such as ‘typed identifier use’ (e.g. a variable name appearing in an expression) and ‘dyadic expression’ (e.g. addition of two values). A type analyzer for a specific language is then defined by stating which language construct(s) play each role. The computational roles provide a framework for understanding the general process and a vocabulary for applying that understanding to the solution of particular problems. We have captured this knowledge in attribute grammar modules that are carefully designed to be combinable and adaptable, exporting language‐independent roles that define the general type analysis problem. From this collection, the compiler designer instantiates the appropriate modules and identifies the relevant source‐language constructs; an attribute grammar processor then weaves the necessary computations into the compiler's semantic analyzer. Our attribute grammar modules provide a precise definition of the actions constituting the various roles and the dependences among them. They can therefore also be used to describe the type analysis process to students, or to specify a hand‐coded semantic analyzer. Copyright © 2009 John Wiley & Sons, Ltd.     

Quantum confinement in PbSe thin films electrodeposited by electrochemical atomic layer epitaxy (EC-ALE)

PbSe is a IV-VI compound semiconductor with a narrow band gap (0.26 eV), used in photodetectors, photoresistors and photoemitters in the infrared (IR). This paper reports the first instance of PbSe formation by electrochemical atomic layer epitaxy (EC-ALE). The film’s composition and structure were characterized using electron probe microanalysis (EPMA) and X-ray diffraction (XRD), respectively. The optical properties were studied via infrared absorption measurements. Films were stoichiometric via EPMA, a Pb/Se ratio of one. XRD indicated the expected rock salt structure for PbSe, and a preferred (2 0 0) orientation. IR adsorption studies, of films grown with 10-50 cycles, showed strong blue shifts of the fundamental absorption edge, which was believed to result from quantum confinement in the thin films.     

Seasonal Unit Root Tests Under Structural Breaks*

Abstract. In this paper, several seasonal unit root tests are analysed in the context of structural breaks at known time and a new break corrected test is suggested. We show that the widely used HEGY test, as well as an LM variant thereof, are asymptotically robust to seasonal mean shifts of finite magnitude. In finite samples, however, experiments reveal that such tests suffer from severe size distortions and power reductions when breaks are present. Hence, a new break corrected LM test is proposed to overcome this problem. Importantly, the correction for seasonal mean shifts bears no consequence on the limiting distributions, thereby maintaining the legitimacy of canonical critical values. Moreover, although this test assumes a breakpoint a priori, it is robust in terms of misspecification of the time of the break. This asymptotic property is well reproduced in finite samples. Based on a Monte‐Carlo study, our new test is compared with other procedures suggested in the literature and shown to hold superior finite sample properties.     

Evolution of high-sensitivity microarray technology

Microarray technology is a multiplex analytical technique for the detection of many different analytes in a mixture of biomolecules. The detection limits for each of the analytes for which the array is designed depend on a multiplicity of reaction parameters, the array itself, and profoundly on the label and detection technology employed. Significant improvements in assay sensitivity have been achieved by optimizing all steps that affect the generation of signal and noise. Nanoparticle technology brings a new dimension to this technology by providing not only higher sensitivity but also improved specificity for hybridization-based microarray assay systems.     

"Combining dispositions and evaluations of vocation and job to account for counterproductive work behavior in adolescent job apprentices": Correction.

Reports an error in "Combining dispositions and evaluations of vocation and job to account for counterproductive work behavior in adolescent job apprentices" by Bernd Marcus and Uwe Wagner (Journal of Occupational Health Psychology, 2007[Apr], Vol 12[2], 161-176). The following errors were committed: (1) In Table 1, item 7 in the variable column is mislabeled. (2) On page 171, in the paragraph before the Discussion section, the sentence beginning on line 14 reads incorrectly. (3) The caption for Figure 1 reads incorrectly. (4) On page 166, left column, 4th line from the bottom, the sentence reads incorrectly. The corrected information is provided. (The following abstract of the original article appeared in record 2007-05780-007.) In the present research, we investigated the joint impact of selected antecedents of counterproductive work behavior (CWB). A sample of German apprentices reported on their CWB and completed measures of situational evaluations (vocational preference, level and constructiveness of job satisfaction) believed to trigger CWB and of dispositional motivators (measured by integrity test subscales) and controls (self-control and another subset of integrity scales) of CWB. All predictors investigated showed the expected bivariate relationships with CWB. Multivariate analyses revealed that the triggering effect of an unfavorable vocational choice on CWB was fully mediated by job satisfaction. When predictors were aggregated, a composite of dispositional control variables had the largest effect on CWB and moderated the effects of motivational dispositions and situational evaluations. These results extend the knowledge on antecedents of CWB by investigating previously overlooked variables and samples and partially replicate recent findings on the joint impact of dispositions and work-related evaluations on CWB. (PsycINFO Database Record (c) 2010 APA, all rights reserved)