运用复合刚度方法对Z型构件支撑屋面系统的侧向约束力分析

复合刚度方法是一种可以预测Z型截面构件支撑的屋面系统侧向受力的方法。该方法将一系列Z型截面作为单自由度系统分析,并采用刚度公式计算系统中不同的构件对于抵抗侧向位移的贡献。从力学理论中推导出屋面系统所需的抗力。     

Assessment of obsessive-compulsive symptom dimensions: Development and evaluation of the Dimensional Obsessive-Compulsive Scale.

Although several measures of obsessive-compulsive (OC) symptoms exist, most are limited in that they are not consistent with the most recent empirical findings on the nature and dimensional structure of obsessions and compulsions. In the present research, the authors developed and evaluated a measure called the Dimensional Obsessive-Compulsive Scale (DOCS) to address limitations of existing OC symptom measures. The DOCS is a 20-item measure that assesses the four dimensions of OC symptoms most reliably replicated in previous structural research. Factorial validity of the DOCS was supported by exploratory and confirmatory factor analyses of 3 samples, including individuals with OC disorder, those with other anxiety disorders, and nonclinical individuals. Scores on the DOCS displayed good performance on indices of reliability and validity, as well as sensitivity to treatment and diagnostic sensitivity, and hold promise as a measure of OC symptoms in clinical and research settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Remediation of heavy metal contaminated soil washing residues with amino polycarboxylic acids

Removal of Cu, Pb, and Zn by the action of the two biodegradable chelating agents [S,S]-ethylenediaminedisuccinic acid (EDDS) and methylglycinediacetic acid (MGDA), as well as citric acid, was tested. Three soil samples, which had previously been treated by conventional soil washing (water), were utilized in the leaching tests. Experiments were performed in batches (0.3 kg-scale) and with a WTC-mixer system (Water Treatment Construction, 10 kg-scale). EDDS and MGDA were most often equally efficient in removing Cu, Pb, and Zn after 10–60 min. Nonetheless, after 10 d, there were occasionally significant differences in extraction efficiencies. Extraction with citric acid was generally less efficient, however equal for Zn (mainly) after 10 d. Metal removal was similar in batch and WTC-mixer systems, which indicates that a dynamic mixer system could be used in full-scale. Use of biodegradable amino polycarboxylic acids for metal removal, as a second step after soil washing, would release most remaining metals (Cu, Pb and Zn) from the present soils, however only after long leaching time. Thus, a full-scale procedure, based on enhanced metal leaching by amino polycarboxylic acids from soil of the present kind, would require a pre-leaching step lasting several days in order to be efficient.     

Regional factors and innovativeness: an empirical analysis of four German industries

A growing body of work emphasizes the importance of regional factors for regional innovativeness. In this paper, about 70 variables approximating the social-economic characteristics of regions are aggregated to 12 regional factors. In four industry-specific set-ups their influence on firms?? innovativeness is tested. The study confirms that inter-industrial differences exist in the importance of these factors. In the empirical analyses a log-linear model is compared with a linear approach. While both are theoretically problematic it is shown that the log-linear model performs better in the empirical assessment.     

Mass-rearing of the redlegged ham beetle, Necrobia rufipes De Geer (Coleoptera: Cleridae) for laboratory research

A new protocol for mass-rearing the redlegged ham beetle, Necrobia rufipes De Geer, in the laboratory is described, that facilitates the production of large numbers of insects with minimal handling. A culture medium comprised of finely ground (150 μm) dried fish, dry dog food and pieces of dried cured ham was tested on N. rufipes. This rearing medium produced significantly larger population numbers when compared with a range of published and unpublished methods. When reared on this medium with initial colonies of 200 mixed sex adult beetles, there was more than a three-fold increase in N. rufipes adult populations from the original numbers over a 7-8 week period. This simple procedure minimizes cannibalism as the larvae were shifted into glass vials for pupal cell formation.     

Microwave assisted click chemistry on a conductive polymer film

Microwave (MW) irradiation has been used to accelerate the functionalization of an azide functional poly(3,4-ethylenedioxythiophene) film by click chemistry. The absorption of MW energy by the conductive polymer has been exploited for localized activation of the reaction on the polymer surface. By use of an alkyne modified fluorescein derivative the reaction conditions have been optimized in a conventional MW oven, enabling the use of different sizes of substrates. The optimization resulted in a reduction of reaction times of approximately 20 h to only 2 min for bulk film functionalization. The method has been applied for anchoring of the chelating agent nitrilotriacetic acid (NTA) on the conductive polymer. The chelating linkage ability of NTA on the surface was investigated through a sandwich ELISA study confirming the selective bonding of a histidine tagged protein.     

Albert Renger—Patzsch's early work: Object and abstraction

Abstract

In photography, one should surely proceed from the essence of the object and attempt to represent it through purely photographic means, regardless of whether it is a human being, a landscape, architecture or something else; whereas today a rape of the object for the sake of formal play is more often the norm. Because the German word Sachlichkeit has taken on practically the opposite meaning today, I have to use a foreign word to properly characterize the position of servitude I maintain before the motif: ‘objectivity’.¹     

Recent Advances in Steels for Coal Fired Power Plant: A Review

The current status of the development of materials for advanced ultra supercritical power generation technology is considered in the light of changes in the priorities and opportunities worldwide for high efficiency power plant fired by coal. These include the slower economic growth, the emphasis on renewable sources, and technical setbacks with the new materials necessary for high temperature operation. Currently martensitic steels are restricted to about 620 °C and since Ni-base alloys cannot be used economically below about 700 °C, the utility industry has had to abandon the traditional incremental approach to the increasing of steam temperature. The major theme of the paper will be the potential of further materials research to identify steels with “Gap Closing” potential i.e. with sufficient strength to operate between the current limit for martensitic steels and the lowest temperature at which the Ni-base alloys become viable. Alloys with some potential in this regard are mentioned and representative properties described.