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151.
A fully automated immunosensor for the herbicide glyphosate has been developed on the basis of the immunocomplex capture assay protocol. The sensor carries out on-line analyte derivatization prior to the assay and uses a selective anti-glyphosate serum, a glyphosate peroxidase enzyme tracer, and fluorescent detection. Under optimal conditions, the detection limit achieved is 0.021 microg/L with an analysis rate of 25 min per assay, autonomy of more than 48 h, and sensor reusability >500 analytical cycles. The immunosensor is able to discriminate structurally related molecules, such as aminomethylphosphonic acid, the main metabolite of glyphosate, and other related herbicides, such as glufosinate and glyphosine. Interferences from naturally occurring species (anions, cations, and humic substances) and their elimination were also studied. The immunosensor has been successfully applied to water and soil sample analysis, with good recoveries at levels lower than 1 microg/L. Results obtained with the immunosensor correlate well with data from a magnetic particle ELISA and LC/LC/MS chromatographic method.  相似文献   
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153.
The diffuse nature of arterial occlusions in Buerger's disease compromises the effect of revascularization. Nevertheless, the muscle branches are quite often unaffected by the occlusive disease making revascularization of collateral arterial branches a promising alternative to conventional procedures. Revascularization by a short autologous venous graft from the grand anastomotic or gastrocnemius artery can be an alternative technique. Advances in microsurgery have made such revascularizations possible.  相似文献   
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155.
Food Science and Biotechnology - Chemical properties of fish gelatins differ from those of conventional mammalian sources, representing an attractive technological alternative for the food...  相似文献   
156.
Sandia National Laboratories has conducted a sequence of studies on the performance of lithium ion and other types of electrochemical cells using inductive models. The objectives of some of these investigations are: (1) to develop procedures to rapidly determine performance degradation rates while these cells undergo life tests; (2) to model cell voltage and capacity in order to simulate cell output under variable load and temperature conditions; (3) to model rechargeable battery degradation under conditions of cyclic charge/discharge, and many others. Among the uses for the models are: (1) to enable efficient predictions of battery life; (2) to characterize system behavior.

Inductive models seek to characterize system behavior using experimentally or analytically obtained data in an efficient and robust framework that does not require phenomenological development. There are certain advantages to this. Among these advantages is the ability to avoid making measurements of hard to determine physical parameters or having to understand cell processes sufficiently to write mathematical functions describing their behavior. We have used artificial neural networks (ANNs) for inductive modeling, along with ancillary mathematical tools to improve their accuracy.

This paper summarizes efforts to use inductive tools for cell and battery modeling. Examples of numerical results are presented.  相似文献   

157.
The impact of zinc chloride (ZnCl2) and calcium chloride (CaCl2) as well as bovine gelatin (BG) on the gel strength of phosphorylated fish gelatin (PFG) from the skin of unicorn leatherjacket was investigated. The gel strength of PFG increased with increasing concentrations of ZnCl2 and CaCl2 (2.5–40 μmol L−1). A higher gel strength was observed with CaCl2, compared with ZnCl2. The gel strength of PFG with 20 μmol L−1 CaCl2 increased by 15.7%, compared to the control gel. Nevertheless, at higher concentration (40 μmol L−1) of both salts, gel strength of PFG decreased. Hardness of gels decreased with increasing PFG content (P < 0.05). Nevertheless, no differences in hardness were found amongst gels with BG/PFG ratios of 4:0 and 3:1 (P ≥ 0.05). Thus, PFG could be used in combination with CaCl2 to substitute for BG at a level of 25%.  相似文献   
158.
In southern Spain, coal seams typically contain pyrite. The mines there are characteristically contaminated by the presence of diverse metals disolved in acidic water. An experimental passive system, containing an anoxic limestone draine, organic matter and wetlands, was constructed to assess how best to inprove the water chemistry. The procedure we used is reported on here so others can learn from what we did.  相似文献   
159.
Consumers demand organic products because they believe that the organic products are more flavorful and respectful to the environment and human health. The effects of organic farming on the minerals contents and aroma composition of Clemenules mandarin juices were studied. Minerals (Fe, Cu, Mn, Zn, Ca, Mg, K, and Na) were quantified using atomic absorption-emission spectroscopy, while volatile compounds were extracted using the dynamic headspace technique and were identified and quantified by GC–MS. In general, organic farming produced a mandarin juice with a higher quality than that produced by conventional agricultural practices. Higher concentrations of both minerals and positive volatile compounds were found in the organic juice, while the formation of off-flavors was higher in the conventional juice, although threshold values were not reached.  相似文献   
160.
德国的珠宝设计散发着一种典型的德国气质,就像德国的宝马、奔驰一样,远远看来,没有特别的装饰,朴实略显厚重,但是,近距离观察,就会因为无瑕疵的工艺和细节的经典处理而感动,心跳不已。德国人就是这样,用他们的工艺撼动人类,而不由得你不赞叹:精工亦是艺术。  相似文献   
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