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Implementation and experimental study on fast object modeling based on multiple structured stripes 总被引:6,自引:0,他引:6
In this paper, a practical structured light-based system for fast object modeling and reconstruction is reported. The system consists of an off-the-shelf digital projector, a video camera and a turntable. The system calibration is implemented accurately and automatically by taking a single image of an illuminated calibration template. The multiple color light stripes emitted by the projector adopt only three colors and the color can be modified easily according to the surface texture of the object. This makes the system widely applicable in many situations, and the assumption about color neutrality, which is a limitation to other similar systems, can be largely relaxed. The registration and merging algorithm is greatly simplified by employing a turntable. The validity and high accuracy of the method are demonstrated by extensive real experiments. 相似文献
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本文中所沿用的概念和符号除特别说明外,其意义与[4,5]相同.本文主要给出了集Pδ(A)的结构以及正规算子A有唯一最佳ω-非负逼近的特征. 相似文献
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Lingling Lu Pan Zhou Biao Hu Xiang Li Rong Huang Fuchao Yu 《Tetrahedron letters》2017,58(37):3658-3661
We report herein an improved Pfitzinger reaction for the synthesis of highly functionalized quinaldines from 1,3-dicarbonyl compounds, isatins and alcohols mediated by TMSCl. This synthesis involves cyclization and esterification in one-step cascade process for the formation of a carboxylate (CO2R) at the 4-position of quinaldine ring. Moreover, this procedure shows highly efficient, good functional group tolerance, operational simplicity, environment-friendly and feasibility of scale up. 相似文献
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Andreia Alves Agnieszka Kucharska Claudio Erratico Fuchao Xu Elly Den Hond Gudrun Koppen Guido Vanermen Adrian Covaci Stefan Voorspoels 《Analytical and bioanalytical chemistry》2014,406(17):4063-4088
Human biomonitoring (HBM) is a scientific technique that allows us to assess whether and to what extent environmental pollutants enter humans. We review here the current HBM efforts for organophosphate esters, emerging flame retardants, perfluoroalkyl substances, and phthalate esters. Use of some of these chemicals has already been banned or restricted; they are regularly detected in the environment, wildlife, and human matrices. Traditionally, blood and urine collection have been widely used as sampling methods. New non-invasive approaches (e.g., saliva, hair, nails) are emerging as valid alternatives since they offer advantages with respect to sampling, handling, and ethical aspects, while ensuring similar reliability and sensitivity. Nevertheless, the identification of biomarkers of exposure is often difficult because chemicals may be metabolized in the human body. For many of the above-mentioned compounds, the mechanisms of the favorable metabolization pathways have not been unraveled, but research on important metabolites that could be used as biomarkers of exposure is growing. This review summarizes the state of the art regarding human exposure to, (non-invasive) HBM of, and metabolism of major organophosphate esters, emerging flame retardants, perfluoroalkyl substances, and phthalate esters currently detected in the environment. Figure
Human biomonitoring of emerging contaminants-non-invasive versus invasive matrices 相似文献
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Two Coordination Polymers based on 2‐Ethyl‐1H‐imidazole‐4,5‐dicarboxylic Acid and 1,3‐Bis(4‐pyridyl)propane: Synthesis,Crystal Structures,and Photoluminescent Properties 下载免费PDF全文
Haibing Wang Ping Tang Guowang Xu Yenan Wang Fuchao Hu Dongsheng Li 《无机化学与普通化学杂志》2015,641(5):848-852
Two coordination polymers, [Cd(Heidc)(bpp)]n ( 1 ) and [Zn3 (eidc)2(bpp)(H2O)2] · 2H2O}n ( 2 ) (H3eidc = 2‐ethyl‐4,5‐imidazole dicarboxylic acid, bpp = 1,3‐bis(4‐pyridyl)propane) were hydrothermally synthesized and characterized by elemental analysis, IR, spectroscopy single‐crystal X‐ray diffraction, and thermogravimetric analyses. Compound 1 features a 2D layer formed by C–H ··· π stacking interactions between adjacent chains, whereas compound 2 shows a 3D (83)2(85.10)‐tfc framework constructed of the 2D (6,3) layer. The result demonstrates that the central metal atoms play a key role in governing the coordination motifs. Moreover, solid‐state properties such as thermal stabilities and photoluminescence of 1 and 2 were also investigated. 相似文献
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Qinhua Chen Peng Li Handong Yang Xiulou Li Jun Zhu Fuchao Chen 《Journal of separation science》2009,32(18):3152-3156
Supercritical fluid was used to extract volatile components from the rhizoma of Atractylode lancea (A. lancea). An orthogonal array design (OAD), L9 (3)4, was employed as a chemometric method for the optimization of the supercritical fluid extraction (SFE) of volatile compounds from the herbal medicine. Four parameters, namely, pressure, temperature, dynamic extraction time, and flow rate of CO2, were studied and optimized by a three‐level OAD in which the interactions between the parameters were neglected. These compounds were identified according to their retention times and mass spectra by GC–MS. A total of 30 compounds of SFE extracts were identified. Atractylon (8.63%), hinesol (1.44%), β‐eudesmol (6.64%), elemol (0.42%), and atractydin (13.92%) were the major sesquiterpenes identified in A. lancea SFE extracts. 相似文献
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Xiaojun Tang Feng Zhang Wenjing Wang Chunrui Tang Yuntao Liang Fuchao Tian 《光谱学快报》2018,51(3):134-138
Addressing the problem of baseline drift or distortion in Fourier transform infrared spectra when analyzing gas continuously at scene, a novel and simple method is proposed to identify and treat spectral baseline drift. Firstly, the spectral baseline was corrected with the common approach followed by standard gas analysis. Then, absorbance of analytes was reconstructed and reduced from the corrected spectrum. Finally, a Fourier transform was performed with the difference spectrum, and the first four-line strengths were used as feature variables to determine if baseline distortion occurred. In the end of this paper, this approach has been applied in the field of wellhead gas logging with Fourier transform infrared. The application results showed that all the spikes had been removed from the raw logging curves, confirming that this approach could be used to identify spectral baseline distortion accurately. 相似文献
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Fuchao Yang Shuyi MaXiaolei Zhang Meng ZhangFaming Li Jing LiuQiang Zhao 《Superlattices and Microstructures》2012
Both ZnO and Cu doped ZnO films with strong c-axis preferred orientation have been successfully prepared on porous silicon substrate, formed by electrochemical anodization, using radio frequency reactive magnetron sputtering method. X-ray diffraction measurements showed that the intensity of (0 0 2) diffraction peak first decreased and then increased with the Cu doping content increasing. Meanwhile new weak (1 0 0), (1 0 1), (1 0 2) and (1 1 0) diffraction peaks appeared after doping. The optical band edge of ZnO:Cu films, deduced from the optical absorption spectra, shifted to a longer wavelength comparing with the undoped sample and we attributed this red shift phenomenon to the decreasing of carrier concentration. The broad light emission from 350 to 800 nm was obtained by combining the blue–green emission from ZnO with red–orange emission from porous silicon. This could be used as a source of white light emitting diode chips underlying the importance of our work. The variation and origin of the emission peaks were discussed through the Gaussian deconvolution, and the Raman scattering spectral revealed the characteristics of porous silicon and multiphonon processes. 相似文献