a selective nh3 gas sensor based on fe2o3–zno nanocomposites at room temperature

... electronegativity of the oxy- gen atom than that of the nitrogen atom. The other is that there is a lone electron pair in NH 3 . What is more important is that low- temperature ammonia oxidation was ... Sensors and Actuators B 114 (2006) 910–915 A selective NH 3 gas sensor based on Fe 2 O 3 –ZnO nanocomposites at room temperature Huixiang Tang, Mi Yan, Hui Zhang, Shenz...

Ngày tải lên: 19/03/2014, 16:47

... chemical reaction between gas and the sensor material [7,8]. Obviously, it would be desirable for many applications if the sensor could operate at temperatures <100 ◦ C or even at room temperature, ... to detect small concentration of NO 2 at low operating temperatures. Li and Kawi [13] have shown that a linear relationship was found between the surface areas of SnO 2 sens...

Ngày tải lên: 20/03/2014, 13:07

... (a) Experimental set-up used for the analysis of NH 3 vapors and (b) schematic drawing of the ammonia gas sensor. 2. Experimental 2.1. Fabrication of gas sensors The gas sensors were fabricated ... Talanta 78 (2009) 199–206 Contents lists available at ScienceDirect Talanta journal homepage: www.elsevier.com/locate/talanta Ammonia gas sensor based on electrosynthesized ... 5a...

Ngày tải lên: 19/03/2014, 16:47

... ratio. One-dimensional ͑1D͒ nanostructures with high surface- to-volume ratio and small grain size have attracted much current attention as candidate materials for solid-state gas sensors. Recently, nanosensors ... operation, which are unattainable by the conventional materials. The major drawback, however, remains due to difficulties in mass pro- duction of sensors based on individual 1...

Ngày tải lên: 20/03/2014, 13:07

... ratio. One-dimensional ͑1D͒ nanostructures with high surface- to-volume ratio and small grain size have attracted much current attention as candidate materials for solid-state gas sensors. Recently, nanosensors ... operation, which are unattainable by the conventional materials. The major drawback, however, remains due to difficulties in mass pro- duction of sensors based on individual 1...

Ngày tải lên: 20/03/2014, 13:07

... Introduction Many studies on various materials as gas sensors have been reported in recent years. Gas sensing materials can be classified mainly into two types, namely, organic and inorganic materials. Semiconductor ... for 30 min. A stainless steel substrate was immersed vertically in the above bath and the bath was heated. At 353 K, the precipitation was started in the bath. During...

Ngày tải lên: 20/03/2014, 13:07

... image watermarking is an attractive alt ernative that matches these necessities.This technique consists in embedding a permanent watermark in a cover ima ge in such a way that the watermarked ... four extracted watermarks are, afterwards, compared t o the original watermark to check the watermark presence in t he attacked image. For objective examination, they cal...

Ngày tải lên: 21/11/2013, 23:58

... check the watermark presence in the attacked image. For objective examination, they calculate the similarity ratio (SR) between each extracted watermark and the original one and admit that the ... permanent watermark in a cover image in such a way that the watermarked image remains accessible to everyone and the embedded watermark can be decoded after the watermarked image have unde...

Ngày tải lên: 30/12/2013, 16:22

... to tackle only pronoun anaphora 1169 resolution (Charniak and Elsner, 2009). The expectation-maximization algorithm (EM) was ap- plied to learn parameters automatically from the parsed version ... pronoun resolution by inco rporating corefer- ential information of candidates. In Proceedings of the 42nd Annual Meeting on Association for Compu- tational Linguistics, page 127. Association ......

Ngày tải lên: 20/02/2014, 04:20

... utterances and context. The speaker and utterance elements contain information about the characters who speak and what they said at each dialogue turn. On the other hand, context elements contain ... contain all the additional information (explanations and descriptions) appearing in the scripts. 39 The extracted dialogues are stored into a data structure such that the informatio...

Ngày tải lên: 07/03/2014, 18:20