Microsystems elements based on free-standing thick-films made with a new sacrificial layer process

A new process derived from screen-printing technology and based on thick sacrificial layers has been developed in our laboratory for the fabrication of films partially released from the substrate. The sacrificial layer acts as a stable mechanical support during the firing of the active layer and is totally removed after the final thermal treatment of the sample. Fabrication of a copper electrothermal actuator was undertaken to demonstrate the efficiency of this simple, collective and low cost process. Passive components based on this new process include the fabrication of heating resistors, strain gauges and microchannels. Moreover, the process can also be used to facilitate the implementation of piezoelectric devices.     

PMD与模式耦合

1 概述 光是由2种方向相互垂直的偏振组成,通常称为电场和磁场(或波),它们沿光纤方向传播.对于给定长度的光纤,其中一条路径的平均应力要小于另一条路径,使光可以更快速地传播,这条路径通常被称为快光轴.快光轴与慢光轴是相互垂直的.     

Accurate environmental bioindication in floodplains in spite of an extreme flood event

The ecological reaction of species on environmental factors can differ both, temporally and geographically. Therefore, bioindicator systems must be shown to remain accurate at different places and points of time. Extreme events pose challenges for testing this robustness, which has not yet been explored systematically. The unique opportunity of the extreme flooding of the river Elbe in August 2002 was used for such a test. The bioindicator system for mean groundwater depth during the vegetation period and annual duration of inundation in floodplains studied here was developed with data collected in 1999. Data from 2003 were used to analyse the dependence of the bioindication results on the humidity of the study plots and taxonomic group (plants, molluscs and carabid beetles). For the duration of inundation, the accuracy of bioindication in 2003 was similar to that in 1999, except for the medium‐humid and dry plots using molluscs as indicators. For groundwater depth, the accuracy of bioindication in 2003 was similar to that of the reference year except in the dry plots with significantly lower accuracy for all species groups. With a few exceptions, the bioindicator system is shown to be robust and to remain accurate in spite of an extreme flood event. In conclusion, the relevance of extreme events for the robustness of bioindicator systems differs between the indicated parameters and taxonomic groups. The results stress the need to take into account the limits of the working range and the occurrence of extreme events, when testing and applying bioindicator systems. Copyright © 2009 John Wiley & Sons, Ltd.     

鲜酒糟加工食醋工艺研究

用根霉、生香酵母、醋酸茵为茵种,以鲜酒糟、棵子（粉碎后的高梁、豆类）和麸皮混合发酵５０－６０天,和产食醋,经精加工后不但可得优质食醋,还可获取较好的经济效益。     

稀土与L-酪氨酸甘氨酸三元固态配合物的合成与表征

在乙醇溶液中合成了四种稀土与 L-酪氨酸、甘氨酸的三元固态配合物 RE( Tyr) 1.5 ( Gly) 4 ( Cl O4) 3( RE=La3+、Ce3+、Gd3+、Y3+) ,并通过摩尔电导、热分析、红外光谱等进行了表征。     

Functionalized Conducting Polymers—Towards Intelligent Materials

Organic conjugated polymers and oligomers constitute a three-dimensional network of molecular wires, in which all monomeric units can be functionalized with various prosthetic groups. By varying the nature of these groups, specific interactions with external physical or chemical phenomena can be developed in these materials, leading to molecular devices such as sensors, transducers, memories and logic operators. Chemists have already mastered the realization of many of these functional elements, which mimic those existing in organized beings. The further assembly of these elements in multifunctionalized organic conducting polymers and oligomers will represent the next step towards intelligent materials.     

Experimental Evidence for the Existence of the Ti3B4 Phase

Experimental evidence for the formation of Ti₃B₄ with an orthorhombic Ta₃B₄-type structure is presented. This phase forms by a peritectic reaction between TiB₂ and liquid at ∼2200°C and is stable to temperatures at least as low as 1690°C, the lowest temperature at which samples were annealed. No evidence was found to indicate the presence of a second high-temperature form of this phase, as has been reported in the literature.