Comparison of capillary electrophoresis and high performance liquid chromatography methods for caffeine determination in decaffeinated coffee

Decaffeinated coffee accounts for 10 percent of coffee sales in the world; it is preferred by consumers that do not wish or are sensitive to caffeine effects. This article presents an analytical comparison of capillary electrophoresis (CE) and high performance liquid chromatography (HPLC) methods for residual caffeine quantification in decaffeinated coffee in terms of validation parameters, costs, analysis time, composition and treatment of the residues generated, and caffeine quantification in 20 commercial samples. Both methods showed suitable validation parameters. Caffeine content did not differ statistically in the two different methods of analysis. The main advantage of the high performance liquid chromatography (HPLC) method was the 42-fold lower detection limit. Nevertheless, the capillary electrophoresis (CE) detection limit was 115-fold lower than the allowable limit by the Brazilian law. The capillary electrophoresis (CE) analyses were 30% faster, the reagent costs were 76.5-fold, and the volume of the residues generated was 33-fold lower. Therefore, the capillary electrophoresis (CE) method proved to be a valuable analytical tool for this type of analysis.

Study of the application of the high performance liquid chromatography-particle beam interface-mass spectrometry technique on some pesiticides and the reduction phenomena in the system

This work includes two major parts. The first part of the work concentrated on the studies of the application of the highperfonnance liquid chromatography-particle beam interface-mass spectrometry system of some pesticides. Factors that have effects on the detection sensitivity were studied. The linearity ranges and detection limits of ten pesticides are also given in this work. The second part of the work concentrated on the studies of the reduction phenomena of nitro compounds in the HPLC-PB-MS system. Direct probe mass spectrometry and gas chromatography-mass spectrometry techniques were also used in the work. Factors that have effects on the reduction of the nitro compounds were studied, and the possible explanation is proposed. The final part of this work included the studies of reduction behavior of some other compounds in the HPLC-PB-MS system, included in them are: quinones, sulfoxides, and sulfones.

Improving Short DNA Sequence Alignment with Parallel Computing

Variations in different types of genomes have been found to be responsible for a large degree of physical diversity such as appearance and susceptibility to disease. Identification of genomic variations is difficult and can be facilitated through computational analysis of DNA sequences. Newly available technologies are able to sequence billions of DNA base pairs relatively quickly. These sequences can be used to identify variations within their specific genome but must be mapped to a reference sequence first. In order to align these sequences to a reference sequence, we require mapping algorithms that make use of approximate string matching and string indexing methods. To date, few mapping algorithms have been tailored to handle the massive amounts of output generated by newly available sequencing technologies. In otrder to handle this large amount of data, we modified the popular mapping software BWA to run in parallel using OpenMPI. Parallel BWA matches the efficiency of multithreaded BWA functions while providing efficient parallelism for BWA functions that do not currently support multithreading. Parallel BWA shows significant wall time speedup in comparison to multithreaded BWA on high-performance computing clusters, and will thus facilitate the analysis of genome sequencing data.

Natural air conditioning, traditions and trends : high performance of sustainable indoor ventilation in a hot and dry climate

De nos jours, l'utilisation accrue de combustibles à base de fossiles et l'électricité met en péril l'environnement naturel à cause des niveaux élevés de pollution. Il est donc plausible de prévoir des économies d'énergie significatives grâce à la climatisation dite «naturelle»». En accord avec les objectifs acceptés à l'échelle internationale d'une architecture «verte» et durable, l'utilisation de cours intérieures associées aux capteurs de vent, aux murs-Trombe et à d'autres systèmes de climatisation naturelle (aussi bien traditionnels que nouveaux), paraît prometteuse. Ce mémoire propose une analyse de nouvelles approches à la climatisation naturelle et à la production d'air frais avec une consommation minimale d'énergie, eu égard aux traditions et aux tendances, en particulier dans les zones climatiques chaudes et sèches comme l'Iran. Dans ce contexte, regarder l'architecture de l'Islam et la discipline du Qur'an paraissent offrir un guide pour comprendre l'approche musulmane aux processus de décision en design. Nous regardons donc les traditions et les tendances en ce qui concerne la climatisation naturelle à travers l'élément le plus important du contexte islamique, à savoir le Qur'an. C'est pourquoi, à l'intérieur du thème de la tradition, nous avons pris en compte quelques considérations concernant l'influence de l'Islam, et en particulier le respect de la nature associé à un équilibre entre l'harmonie et l'individualité. Ce sont autant de facteurs qui influencent la prise de décisions visant à résoudre des problèmes scientifiques majeurs selon la philosophie et les méthodes islamiques ; ils nous permettent de faire quelques recommandations. La description des principes sous-jacents aux capteurs à vent et des antécédents trouvés dans la nature tels que les colonies de termites, est présentée également. Sous la rubrique tendances, nous avons introduit l'utilisation de matériaux et de principes de design nouveaux. Regarder simultanément ces matériaux nouveaux et l'analogie des colonies de termites suggère de bonnes approches à la conception d'abris pour les victimes de tremblements de terre dans les régions sisimques. Bam, une ville iranienne, peut être considérée comme un exemple spécifique illustrant où les principes exposés dans ce mémoire peuvent s'appliquer le plus adéquatement.

Efficient Transmitter/Receiver Architectures for High Performance Wireless Applications

The thesis focuses on efficient design methods and reconfiguration architectures suitable for higher performance wireless communication .The work presented in this thesis describes the development of compact,inexpensive and low power communication devices that are robust,testable and capable of handling multiple communication standards.A new multistandard Decimation Filter Design Toolbox is developed in MATLAB GUIDE environment.RNS based dual-mode decimation filters reconfigurable for WCDMA/WiMAX and WCDMA/WLANa standards are designed and implemented.It offers high speed operation with lesser area requirement and lower dynamic power dissipation.A novel sigma-delta based direct analog-to-residue converter that reduces the complexity of RNS conversion circuitry is presented.The performance of an OFDM communication system with a new RRNS-convolutional concatenated coding is analysed and improved BER performance is obtained under different channel conditions. Easily testable MAC units for filters are presented using Reed-Muller logic for realization.

Microwave exfoliated reduced graphene oxide epoxy nanocomposites for high performance applications

Graphene has captured the attention of scientific community due to recently emerging high performance applications. Hence, studying its reinforcing effects on epoxy resin is a significant step. In this study, microwave exfoliated reduced graphene oxide (MERGO) was prepared from natural graphite for subsequent fabrication of epoxy nanocomposites using triethylenetetramine (TETA) as a curing agent via insitu polymerization. Thermogravimetric analysis (TGA), X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), C13 NMR spectroscopy, X-ray photoelectron spectroscopy (XPS) and ultravioletevisible (UVevis) spectroscopy were employed to confirm the simultaneous reduction and exfoliation of graphene oxide. The reinforcing effect of MERGO on epoxy resin was explored by investigating its static mechanical properties and dynamic mechanical analysis (DMA) at MERGO loadings of 0 to 0.5 phr. The micro-structure of epoxy/MERGO nanocomposites was investigated using scanning electron microscope (SEM), transmission electron microscope (TEM) and XRD techniques. The present work reports an enhancement of 32%, 103% and 85% in tensile, impact and flexural strength respectively of epoxy by the addition of even 0.25 phr MERGO. At this loading elastic and flexural moduli also increased by 10% and 65%, respectively. Single-edge-notch three-point-Bending (SEN-TPB) fracture toughness (KIC) measurements were carried out where a 63% increase was observed by the introduction of 0.25 phr MERGO. The interfacial interactions brought about by graphene also benefited the dynamic mechanical properties to a large extent in the form of a significant enhancement in storage modulus and slightly improved glass transition temperature. Considerable improvements were also detected in dielectric properties. The epoxy nanocomposite also attained an ac conductivity of 10 5 S/m and a remarkable increase in dielectric constant. The simple and cost effective way of graphene synthesis for the fabrication of epoxy/MERGO nanocomposites may be extended to the preparation of other MERGO based polymer nanocomposites. This remarkable class of materials has thrown open enormous opportunities for developing conductive adhesives and in microelectronics

Implementation Workshop: High Performance Work Organizations

Since the rise of the industrial revolution, there are few challenges that compare in scale and scope with the challenge of implementing lean principles in order to achieve high performance work systems. This report summarize key insights and learning by representatives from a cross section of organizations who are on this journey. Specifically, we report on findings from the first Lean Aircraft Initiative (LAI) Implementation Workshop, which was held on February 5-6, 1997.

Implementation Workshop: High Performance Work Organizations

Since the rise of the industrial revolution, there are few challenges that compare in scale and scope with the challenge of implementing lean principles in order to achieve high performance work systems. This report summarize key insights and learning by representatives from a cross section of organizations who are on this journey. Specifically, we report on findings from the first Lean Aircraft Initiative (LAI) Implementation Workshop, which was held on February 5-6, 1997. The report is not a “cookbook” or a “how to” manual. Rather, it is a summary of the first phase in a learning process. It is designed to codify lessons learning, facilitate diffusion among people not at the session, and set the stage for further learning about implementation.

Green IT (includes High Powered Computing) - background reading

Background reading for coursework to prepare a technical report as part of the orientation phase. These items are business documents (i.e. grey literature) which might be read as a prelude or complement to finding information in peer reviewed academic publications. grey literature links and articles to be used in preparation of technical report. See also overview guidance document for this assignment http://www.edshare.soton.ac.uk/8017/

The influence of human capital of the workforce in the adoption of high-performance work systems : the case of Portugal and Spain. 'La influencia del capital humano de la mano de obra en la adopción de sistemas de trabajo de alto rendimiento: el caso de Portugal y España'.

Resumen tomado de la publicación

Achieving accurate FTIR measurements on high performance bandpass filters

The sources of ordinate error in FTIR spectrometers are reviewed with reference to measuring small out-of-band features in the spectra of bandpass filters. Procedures for identifying instrumental artefacts are described. It is shown that features well below 0.01%T can be measured reliably.