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Raman spectra from three different binary gasoline-ethanol blends (with ratios 95:5, 90:10, and 85:15) have been obtained by using a low-cost, frequency precise Fourier-transform Raman spectrometer (FT-Raman) prototype. The spectral information is presented in the range of 0 to 3500 cm-1 with a resolution of 1.66 cm-1, which is greater than the required for most liquid and solid chemical samples. This set-up delivers spectral information about the sample with a reduced spectral deviation compared to theoretical values (less than 0.4 cm-1 without compensation for instrumental response). The robust and highly fexible FT-Raman prototype presented for the spectral analysis, consisting mainly of a Michelson interferometer and a self-designed photon counter, is able to deliver high resolution and frequency precise Raman spectra from the gasoline-ethanol blends comparable to the obtained by using commercial devices. This FT-Raman set-up does not need additional complex hardware or software control and relies on re-sampling and interpolation algorithms. The qualitative spectral information obtained has been used to calculate the proportion of gasoline and ethanol present in the used chemical samples without using extra calibrations methods or chemical markers.
Today's network landscape consists of many different network technologies, a wide range of end-devices with a large scale of capabilities and power, and an immense quantity of information and data represented in different formats. Research on 3D imaging, virtual reality and holographic techniques will result in new user interfaces (UI) for mobile devices and will increase their diversity and variety. In this paper software architecture has been proposed to establish device and content format independent communication, implemented in Language Learning Game (LLG).
Network landscape of recent time contains many different network technologies, a wide range of end-devices with a large scale of capabilities and power, and an immense quantity of information and data represented in different formats. Research on 3D imaging, virtual reality and holographic techniques will result in new user interfaces (UI) for mobile devices, will increase their diversity and variety. In this paper software architecture has been proposed to establish device and content format independent communication including 3D imaging and virtual reality data as content. As experimental validation the concept is implemented in collaborative Language Learning Game (LLG), which is a learning tool for language acquisition.
The improvements in the hardware and software of communication devices have allowed running Virtual Reality (VR) and Augmented Reality (AR) applications on those. Nowadays, it is possible to overlay synthetic information on real images, or even to play 3D on-line games on smart phones or some other mobile devices. Hence the use of 3D data for business and specially for education purposes is ubiquitous. Due to always available at hand and always ready to use properties of mobile phones, those are considered as most potential communication devices. The total numbers of mobile phone users are increasing all over the world every day and that makes mobile phones the most suitable device to reach a huge number of end clients either for education or for business purposes. There are different standards, protocols and specifications to establish the communication among different communication devices but there is no initiative taken so far to make it sure that the send data through this communication process will be understood and used by the destination device. Since all the devices are not able to deal with all kind of 3D data formats and it is also not realistic to have different version of the same data to make it compatible with the destination device, it is necessary to have a prevalent solution. The proposed architecture in this paper describes a device and purpose independent 3D data visibility any time anywhere to the right person in suitable format. There is no solution without limitation. The architecture is implemented in a prototype to make an experimental validation of the architecture which also shows the difference between theory and practice.
Monitoring of the molecular structure of lubricant oil using a FT-Raman spectrometer prototype
(2014)
The determination of the physical state of the lubricant materials in complex mechanical systems is highly critical from different points of view: operative, economical, environmental, etc. Furthermore, there are several parameters that a lubricant oil must meet for a proper performance inside a machine. The monitoring of these lubricants can represent a serious issue depending on the analytical approach applied. The molecular change of aging lubricant oils have been analyzed using an all-standard-components and self-designed FT-Raman spectrometer. This analytical tool allows the direct and clean study of the vibrational changes in the molecular structure of the oils without having direct contact with the samples and without extracting the sample from the machine in operation. The FT-Raman spectrometer prototype used in the analysis of the oil samples consist of a Michelson interferometer and a self-designed photon counter cooled down on a Peltier element arrangement. The light coupling has been accomplished by using a conventional 62.5/125μm multi-mode fiber coupler. The FT-Raman arrangement has been able to extract high resolution and frequency precise Raman spectra, comparable to those obtained with commercial FT-Raman systems, from the lubricant oil samples analyzed. The spectral information has helped to determine certain molecular changes in the initial phases of wearing of the oil samples. The proposed instrument prototype has no additional complex hardware components or costly software modules. The mechanical and thermal irregularities influencing the FT-Raman spectrometer have been removed mathematically by accurately evaluating the optical path difference of the Michelson interferometer. This has been achieved by producing an additional interference pattern signal with a λ= 632.8 nm helium-neon laser, which differs from the conventional zero-crossing sampling (also known as Connes advantage) commonly used by FT-devices. It enables the FT-Raman system to perform reliable and clean spectral measurements from the analyzed oil samples.
The Raman spectra from the chemical compounds toluene and cyclohexane obtained using a Fourier Transform (FT)-Raman spectrometer prototype have been contrasted with the Raman spectra of these same materials collected with two different commercial FT-Raman devices. The FT-Raman spectrometer consist of a Michelson interferometer, a self-designed photon counter and a reference photo-detector. The evaluation methodology of the spectral information, contrary to the commercial devices that commonly use the zero-crossing method, is carried out by re-sampling the Raman scattering and by accurately extracting the optical path information of the Michelson interferometer. The FTRaman arrangement has been built using conventional parts without disregarding the spectral frequency precision that usually such a FTRaman instruments deliver. No additional complex hardware components or costly software modules have been included in this FT-Raman device. The main Raman lines from the spectra obtained with the three FT-Raman devices have been compared with the Raman lines from the standard Raman spectra of these two materials. The values obtained using the FT-Raman spectrometer prototype have shown a frequency accuracy comparable to that obtained with the commercial devices without facing the need for a large investment. Although the proposed FT-Raman prototype cannot be directly compared to the last generation of FT-Raman spectrometers from the commercial manufacturers, such a device could give an opportunity to users that require high frequency precision in their spectral analysis and are provided with rather scarce resources.
This paper treats the Brillouin backscattering in a single mode optical fiber and its implications on the Brillouin Ring Laser Gyroscope (BRLG). The BRLG consists of a fiber ring cavity in which stimulated Brillouin scattering is induced and provides two resonant counterpropagating backscattered waves. If this cavity is rotating around its axis, the backscattered waves get different resonant frequencies because of the Sagnac effect. The frequency difference is proportional to the rotation rate (Omega) by inducing a frequency offset between the counterpropagating waves. Some reported Brillouin spectra exhibit several peaks, which means that one pump wave provides at least two backscattered waves with distinguishable frequencies. In order to understand this multi-backscattering and to take advantage of it for the BRLG, we present results of a simulation of the Brillouin backscattering in a single mode optical fiber.
This paper treats the interaction between acoustic modes and light (Brillouin scattering) in a single mode optical fibre. Different observed spectra of the Brillouin backscattering in several fibres have been already reported. In order to have a clear idea of the process, we made a simulation to be able to `draw' the theoretical Brillouin spectrum of an optical fibre and to identify the origin of the observed backscattered lines.
First, the model and the computation method used in our simulation are described. Second, the experimentally observed spectra of two real fibres are compared with their computed spectra. Real spectra and simulated spectra are in good agreement.
Our work provides an interesting tool to investigate the changes in the Brillouin spectrum when the input parameters (characteristics of an optical fibre) vary. This should give useful indications to people working on systems which use Brillouin backscattering.
La industria del bacanora en Sonora, México, enfrenta la influencia de una compleja red de factores culturales, tecnológicos, económicos y legales que inhiben su desarrollo. Ello ocurre pese al esfuerzo institucional por radicar un marco normativo que elimine la práctica de los métodos informales de elaboración que derivan en calidades heterogéneas de licor. El conseguirlo se complica ante la dificultad que enfrentan los actores de esta industria para implementar prácticas efectivas de verificación de las normas vigentes en los confines de la geografía de la Denominación de Origen. En este documento se describe el uso de un prototipo de espectrómetro Raman por transformada de Fourier para analizar cualitativamente muestras desconocidas de bacanora. Este dispositivo se construyó con el uso de un interferómetro Michelson convencional, un contador de fotones de diseño propio y un foto-detector de referencia. Los resultados del trabajo confirman que dada su naturaleza de diseño y construcción, este instrumento de medición y su efectiva técnica de operación a bajo costo, constituye una alternativa viable, adaptable fácilmente a las necesidades de los actores productivos e institucionales, para asistirlos en la elaboración de bacanora y a la verificación de su calidad conforme a los criterios de la normatividad.
The combination of fossil-derived fuels with ethanol and methanol has acquired relevance and attention in several countries in recent years. This trend is strongly affected by market prices, constant geopolitical events, new sustainability policies, new laws and regulations, etc. Besides bio-fuels these materials also include different additives as anti-shock agents and as octane enhancer. Some of the chemical compounds in these additives may have harmful properties for both environment and public health (besides the inherent properties, like volatility). We present detailed Raman spectral information from toluene (C7H8) and ethanol (C2H6O) contained in samples of ElO gasoline-ethanol blends. The spectral information has been extracted by using a robust, high resolution Fourier-Transform Raman spectrometer (FT-Raman) prototype. This spectral information has been also compared with Raman spectra from pure additives and with standard Raman lines in order to validate its accuracy in frequency. The spectral information is presented in the range of 0 cm-1 to 3500 cm-1 with a resolution of 1.66cm-1. This allows resolving tight adjacent Raman lines like the ones observed around 1003cm-1 and 1030cm-1 (characteristic lines of toluene). The Raman spectra obtained show a reduced frequency deviation when compared to standard Raman spectra from different calibration materials. The FT-Raman spectrometer prototype used for the analysis consist basically of a Michelson interferometer and a self-designed photon counter cooled down on a Peltier element arrangement. The light coupling is achieved with conventional62.5/125μm multi-mode fibers. This FT-Raman setup is able to extract high resolution and frequency precise Raman spectra from the additives in the fuels analyzed. The proposed prototype has no additional complex hardware components or costly software modules. The mechanical and thermal disturbances affecting the FT-Raman system are mathematically compensated by accurately extracting the optical path information of the Michelson interferometer. This is accomplished by generating an additional interference pattern with a λ = 632.8 nm Helium-Neon laser (HeNe laser). It enables the FT-Raman system to perform reliable and clean spectral measurements from the materials under observation.