954 resultados para RAPID ANALYSIS


Relevância:

70.00% 70.00%

Publicador:

Resumo:

A suite of computer subroutines is described which allows rapid analysis of most types of planar mechanism by the writing of a simple computer programme. The analytical techniques of these subroutines are explained, and a worked example is presented to illustrate the use of the package, and to demonstrate its advantages in the calculation of inertia forces within a mechanism.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

In this paper, the capabilities of laser-induced break down spectroscopy (LIBS) for rapid analysis to multi-component plant are illustrated using a 1064 nm laser focused onto the surface of folium lycii. Based on homogeneous plasma assumption, nine of essential micronutrients in folium lycii are identified. Using Saha equation and Boltzmann plot method electron density and plasma temperature are obtained, and the irrelative concentration (Ca, Mg, Al, Si, Ti, Na, K, Li, and Sr) are obtained employing a semi-quantitative method.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Monensin, a carboxylic acid ionophore, is commonly fed to poultry to control coccidiosis. A method for rapid analysis of unextracted poultry plasma samples has been developed based on a novel immunoassay format: one-step all-in-one dry reagent time resolved fluorimetry. All assay specific components were pre-dried onto microtitration plate wells. Only addition of the serum sample diluted in assay buffer was required to perform analysis. Results were available one hour after sample addition. The limit of detection (mean + 3s) of the assay calculated from the analysis of 23 known negative samples was 14.2 ng ml(-1). Intra- and inter-assay RSD were determined as 15.2 and 7.4%, respectively, using a plasma sample fortified with 50 ng ml(-1) monensin. Eight broiler chickens were fed monensin at a dose rate of 120 mg kg(-1) feed for one week, blood sampled then slaughtered without drug withdrawal. Plasma monensin concentrations, as determined by the fluoroimmunoassay ranged from 101-297 ng ml(-1). This compared with monensin liver concentrations, determined by LC-MS, which ranged fi om 13-41 ng g(-1). The fluoroimmunoassay described is extremely user friendly, gives particularly rapid results and is suitable for the detection and quantification of plasma monensin residues. Data from medicated poultry suggest that analysis of plasma may be useful in predicting the extent of monensin liver residues.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

The use of handheld near infrared (NIR) instrumentation, as a tool for rapid analysis, has the potential to be used widely in the animal feed sector. A comparison was made between handheld NIR and benchtop instruments in terms of proximate analysis of poultry feed using off-the-shelf calibration models and including statistical analysis. Additionally, melamine adulterated soya bean products were used to develop qualitative and quantitative calibration models from the NIRS spectral data with excellent calibration models and prediction statistics obtained. With regards to the quantitative approach, the coefficients of determination (R2) were found to be 0.94-0.99 with the corresponding values for the root mean square error of calibration and prediction were found to be 0.081-0.215 % and 0.095-0.288 % respectively. In addition, cross validation was used to further validate the models with the root mean square error of cross validation found to be 0.101-0.212 %. Furthermore, by adopting a qualitative approach with the spectral data and applying Principal Component Analysis, it was possible to discriminate between adulterated and pure samples.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Surface engineering in solids has become an important field in materials science. Glow-discharge optical emission spectrometry (GD-OES) has proven to be a powerful tool for the rapid analysis of elements in the surface of solids. One may employ GD-OES to determine quantitatively the bulk concentration of elements in a sample, and elemental concentrations as a function of depth. Presented here is an overview of GD-OES analysis and an application to aluminium.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Glow-Discharge Optical Emission Spectrometry (GD-OES) is a powerful technique for the rapid analysis of elements in a solid surface as a function of depth. DC-GD-OES allows depth profiling on electrically conductive surfaces only, and has proven to be difficult for the analysis of insulating layers, such as oxides. However, the technique of radio-frequency (RF) GD-OES has the advantage of being able to depth profile through multiple layers, both conducting and insulating. In this work, a LECO GDS- 850A spectrometer was calibrated for aluminium, oxygen, and other elements, with the RF source installed. A quantitative depth profile for a sample of tempered aluminium alloy 7475 is presented and compared with earlier work[1,2].

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Glow-discharge optical emission spectrometry (GD-OES) is a powerful tool for the rapid analysis of elements in the surface of solids. One may employ GD-OES to determine quantitatively the bulk concentration of elements in a sample. With further calibration, one may also obtain elemental concentrations as a function of depth into the sample. This allows depth profiling on a host of advanced materials: treated metals, coated metals and other materials, multi-layers, painted surfaces, hard samples coated with polymers, thin films, and many others.

A consortium of institutions in Victoria, led by Deakin University, has purchased a new glow-discharge optical emission spectrometer. This instrument has the ability to perform elemental depth profiling on a wide range of materials. This technique, the first of its kind in Australia, is of particular interest to those working on metals, ceramics, glasses, coatings, semi-conductors, and multi-layers. We present here an overview of depth profiling by GD-OES and some examples of its use.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Trichophyton rubrum is the most common pathogen causing dermatophytosis. Molecular strain-typing methods have recently been developed to tackle epidemiological questions and the problem of relapse following treatment. A total of 67 strains of T rubrum were screened for genetic variation by randomly amplified polymorphic DNA (RAPD) analysis, with two primers, 5'-d[GGTGCGGGAA]-3' and 5'-d[CCCGTCAGCA]-3', as well as by subrepeat element analysis of the nontranscribed spacer of rDNA, using the repetitive subelements TRS-1 and TRS-2. A total of 12 individual patterns were recognized with the first primer and 11 with the second. Phylogenetic analysis of the RAPID products showed a high degree of similarity (> 90 %) among the epidemiologically related clinical isolates, while the other strains possessed 60% similarity. Specific amplification of TRS-1 produced three strain-characteristic banding patterns (PCR types); simple patterns representing one copy of TRS-1 and two copies of TRS-2 accounted for around 85 % of all isolates. It is concluded that molecular analysis has important implications for epidemiological studies, and RAPID analysis is especially suitable for molecular typing in T. rubrum.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Miniaturized analytical devices, such as heated nebulizer (HN) microchips studied in this work, are of increasing interest owing to benefits like faster operation, better performance, and lower cost relative to conventional systems. HN microchips are microfabricated devices that vaporize liquid and mix it with gas. They are used with low liquid flow rates, typically a few µL/min, and have previously been utilized as ion sources for mass spectrometry (MS). Conventional ion sources are seldom feasible at such low flow rates. In this work HN chips were developed further and new applications were introduced. First, a new method for thermal and fluidic characterization of the HN microchips was developed and used to study the chips. Thermal behavior of the chips was also studied by temperature measurements and infrared imaging. An HN chip was applied to the analysis of crude oil – an extremely complex sample – by microchip atmospheric pressure photoionization (APPI) high resolution mass spectrometry. With the chip, the sample flow rate could be reduced significantly without loss of performance and with greatly reduced contamination of the MS instrument. Thanks to its suitability to high temperature, microchip APPI provided efficient vaporization of nonvolatile compounds in crude oil. The first microchip version of sonic spray ionization (SSI) was presented. Ionization was achieved by applying only high (sonic) speed nebulizer gas to an HN microchip. SSI significantly broadens the range of analytes ionizable with the HN chips, from small stable molecules to labile biomolecules. The analytical performance of the microchip SSI source was confirmed to be acceptable. The HN microchips were also used to connect gas chromatography (GC) and capillary liquid chromatography (LC) to MS, using APPI for ionization. Microchip APPI allows efficient ionization of both polar and nonpolar compounds whereas with the most popular electrospray ionization (ESI) only polar and ionic molecules are ionized efficiently. The combination of GC with MS showed that, with HN microchips, GCs can easily be used with MS instruments designed for LC-MS. The presented analytical methods showed good performance. The first integrated LC–HN microchip was developed and presented. In a single microdevice, there were structures for a packed LC column and a heated nebulizer. Nonpolar and polar analytes were efficiently ionized by APPI. Ionization of nonpolar and polar analytes is not possible with previously presented chips for LC–MS since they rely on ESI. Preliminary quantitative performance of the new chip was evaluated and the chip was also demonstrated with optical detection. A new ambient ionization technique for mass spectrometry, desorption atmospheric pressure photoionization (DAPPI), was presented. The DAPPI technique is based on an HN microchip providing desorption of analytes from a surface. Photons from a photoionization lamp ionize the analytes via gas-phase chemical reactions, and the ions are directed into an MS. Rapid analysis of pharmaceuticals from tablets was successfully demonstrated as an application of DAPPI.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Foot-and-mouth disease is an acute and highly contagious febrile disease affecting cloven-footed animals. Identification of the foot-and-mouth disease virus (FMDV), the causative agent of the disease, posed problems because of the occurrence of many types and subtypes of the virus. A molecular approach based on oligonucleotide mapping of FMDV RNA has been used for the identification and characterization of virus isolates obtained in a disease outbreak (King et al., 1981). One-dimensional oligonucleotide mapping was used for rapid analysis of FMDV RNA (LaTorre et al., 1982). FMDV types Ο and Asia 1 of Indian origin are being routinely used for vaccine production in India. This report presents the differences between FMDV types Ο and Asia 1 at molecular level based on one-dimensional oligonucleotide mapping of virus-induced poly (A) RNA.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

In this paper, we propose a H.264/AVC compressed domain human action recognition system with projection based metacognitive learning classifier (PBL-McRBFN). The features are extracted from the quantization parameters and the motion vectors of the compressed video stream for a time window and used as input to the classifier. Since compressed domain analysis is done with noisy, sparse compression parameters, it is a huge challenge to achieve performance comparable to pixel domain analysis. On the positive side, compressed domain allows rapid analysis of videos compared to pixel level analysis. The classification results are analyzed for different values of Group of Pictures (GOP) parameter, time window including full videos. The functional relationship between the features and action labels are established using PBL-McRBFN with a cognitive and meta-cognitive component. The cognitive component is a radial basis function, while the meta-cognitive component employs self-regulation to achieve better performance in subject independent action recognition task. The proposed approach is faster and shows comparable performance with respect to the state-of-the-art pixel domain counterparts. It employs partial decoding, which rules out the complexity of full decoding, and minimizes computational load and memory usage. This results in reduced hardware utilization and increased speed of classification. The results are compared with two benchmark datasets and show more than 90% accuracy using the PBL-McRBFN. The performance for various GOP parameters and group of frames are obtained with twenty random trials and compared with other well-known classifiers in machine learning literature. (C) 2015 Elsevier B.V. All rights reserved.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Identifying cellular processes in terms of metabolic pathways is one of the avowed goals of metabolomics studies. Currently, this is done after relevant metabolites are identified to allow their mapping onto specific pathways. This task is daunting due to the complex nature of cellular processes and the difficulty in establishing the identity of individual metabolites. We propose here a new method: ChemSMP (Chemical Shifts to Metabolic Pathways), which facilitates rapid analysis by identifying the active metabolic pathways directly from chemical shifts obtained from a single two-dimensional (2D) C-13-H-1] correlation NMR spectrum without the need for identification and assignment of individual metabolites. ChemSMP uses a novel indexing and scoring system comprised of a ``uniqueness score'' and a ``coverage score''. Our method is demonstrated on metabolic pathways data from the Small Molecule Pathway Database (SMPDB) and chemical shifts from the Human Metabolome Database (HMDB). Benchmarks show that ChemSMP has a positive prediction rate of >90% in the presence of deduttered data and can sustain the same at 60-70% even in the presence of noise, such as deletions of peaks and chemical shift deviations. The method tested on NMR data acquired for a mixture of 20 amino acids shows a success rate of 93% in correct recovery of pathways. When used on data obtained from the cell lysate of an unexplored oncogenic cell line, it revealed active metabolic pathways responsible for regulating energy homeostasis of cancer cells. Our unique tool is thus expected to significantly enhance analysis of NMIR-based metabolomics data by reducing existing impediments.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Gas turbine compression systems are required to perform adequately over a range of operating conditions. Complexity has encouraged the conventional design process for compressors to focus initially on one operating point, usually the most commonor arduous, to draw up an outline design. Generally, only as this initial design is refined is its offdesign performance assessed in detail. Not only does this necessarily introduce a potentially costly and timeconsuming extra loop in the design process, but it also may result in a design whose offdesign behavior is suboptimal. Aversion of nonintrusive polynomial chaos was previously developed in which a set of orthonormal polynomials was generated to facilitate a rapid analysis of robustness in the presence of generic uncertainties with good accuracy. In this paper, this analysis method is incorporated in real time into the design process for the compression system of a three-shaft gas turbine aeroengine. This approach to robust optimization is shown to lead to designs that exhibit consistently improved system performance with reduced sensitivity to offdesign operation.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

本学位论文分为四个部分,第一部分报道了用串联质谱快速分析合成药物中的微量杂质成分以及分析中药材中的化学成分。第二部分报道了通过质谱和串联质谱发现并合成新型的PdPincer 催化剂,同时对其活性进行测试。第三部分为串联质谱自动解析软件的设计及应用。第四部分概述了应用在质谱中的各种碎裂方式。 第一部分首先总结了5-溴粉防己碱及其类似物的裂解规律,并以此为根据推测出2 个微量杂质的结构。随后针对无患子(Sapindus mukurossi Gatren.)中的皂苷成分,由ESI-QTOF 得到各个皂苷成份的高分辨质量数据进而得到其分子式,然后利用ESI-IT 电喷雾串联质谱对无患子总皂苷中各皂苷成分的结构进行进一步的鉴定。进而以同样的方式,先通过ESI-QTOF 得到黄山药(Dioscoreapanthaica)总皂苷中各个组分化合物的分子式,然后对已有的薯蓣皂苷标准品做串联质谱分析,以得到该类化合物的裂解规律并给出解析该类化合物的流程图。在此利用计算化学的方法讨论了离子的丰度与裂解活化能之间的关系。然后应用APCI-MS/MS 方法探讨了四对同分异构体和几个已知的化合物,并最后用液质联用对其进行确认,同时还给出了4 个未知化合物的可能结构。 第二部分报道通过质谱和串联质谱发现并合成新型的PdPincer 催化剂,同时对其活性进行测试。钯催化的交联反应是有机合成中C-C 键形成的最有效的方法,且硫脲是一类对空气和水都稳定的化合物,因此我们设计并合成了一系列的硫脲钯催化剂并得到了很好的催化活性。我们在对其中一类环状双硫脲化合物进行质谱实验的时候,在正离子模式下发现了反常的[M.H]+,通过串联质谱进一步确定了它是一种新型的PdPincer 结构。我们将其合成出来并通过X-ray 衍射实验确定了它的结构。同时测定其催化活性并与未形成pincer 的类似物进行比较发现该类化合物具有较宽的底物适用性。 第三部分为串联质谱自动解析软件的设计及应用。通过前面两部分的启示,独立设计开发了AuMass(1.0)。其算法是:先通过查找特殊的碎片离子,中性丢失或碎片离子质量差来确定某类化合物的骨架结构,然后利用该类化合物的自动解析流程来对其周边取代基进行确认。通过它快速地对白芍中的化学成分进行解析,并对未知的化合物进行了推测。为了增加它的解析能力,我又对其它类型的化合物裂解规律进行总结,并给出了自动解析流程。实践证明该软件具有相当好的应用价值。 第四部分综述了应用在质谱上的各类母离子的碎裂技术。这里包括了碰撞诱导裂解(CID)、光诱导碎裂(LID)、电子捕获裂解/电子转移裂解(ECD/ETD)、红外多光子解离(IRMPD)、黑体辐射解离(BIRD)和PQD 裂解技术。 This dissertation consists of four chapters. The first chapter reports the rapidanalysis of trace impurities from synthetical medicine and analysis of the chemicalconstitutents from Chinese herb medicines. The second chapter elaborates the studieson the discorvery and synthesis of new type of Pd Pincer catalyst by using MS andtandem MS together with the testing of its catalyst activity. The third chapter dwellson the designation and development of automatic tandem mass spectrometry analysissoftware. The last chapter presents a review on the dissociation technique of massspectrometry. The first chapter reports the rapid analysis of trace impurities from synthesismedicine and analysis of the chemical constitutents from Chinese herb medicines. The fission mechanism of 5-bromotetrandrine was obtained by analysis of the dissociationpathways of major product, by using which the possible structure of the two traceimpurties was assumed. There are lots of saponins in Sapindus mukurossi. Except forthe good spumescence and decontamination,it possesses the bioactivity of antigenand antitch. First of all, the high resolution mass information was obtained by ESI-QTOF. Hence the possible molecular formulars were acquired too. Then weconducted the further detection of the structures of its saponins by using ESI-ITtechnology. In the same manner, first the molecular formulars of every constituentfrom Dioscorea panthaica in total saponins were obtained by ESI-QTOF, and thenacquired the fission mechanism of this type of compounds by tandem massexperiment on a series of known and available saponins. In the same time, theanalysis flowchart was concluded. Here the relationship between the ion intensity andthe corresponding dissiociation activation energy was studied by computer chemistry.Then the four pairs of isomers were differentiated by APCI-MS/MS, as well as thecharacterization of known and unknown compounds. The assumption was confirmed by HPLC-MS/MS. Among them the possible structures of four unknown saponinswas presented. The second part was discovery and synthesis of a new type of Pd pincer catalystby MS and tandem MS. The coupling reaction catalyzed by Pd is the most effectivemethod in C-C formation in organic synthesis. Apart from that, thiourea is type ofcompounds that are stable to atmosphere and moisture. Hence we designed a series ofPd thiourea catalysts. Some of them show the excellent catalyst activity. The abnormalparent ion [M.H]+ was founded in positive ESI mode when we conduct some massspectrometry experiments on the bicyclical thiourea Pd complex. The structure wasproposed by mass and tandem mass spectrometry. Because it was a new type of pincer,we want to test its catalyst activity. So the Pd pincer was synthesized and the detailstructure was obtained by x-ray experiment. It shows the more fitness in catalysis ofSuzuki reaction by comparison with the analogue. The third chapter dwells on the design and development of automatic tandemmass spectrometry analysis software. Inspired by the former two chapters, theAuMass (version 1.0) was developed. Its algorithm is: first check the diagnostic ion,diagnostic neutral loss or diagnostic ions mass intervals in database to find out whatthe analyst’s skeleton belongs to, then identify the peripheral functional group by thecorresponding analysis flowchart. The chemical constituents of Paeonia lactiflorawere identified rapidly by using AuMass. To increase the analysis ability, the othertypes of compounds from Chinese herbs was concluded. Actually, the software isproven to have the much valuable application. The last chapter presented the review on the some kinds of fission technique ofmass spectrometry. It involves the collision induced dissociation (CID), laser induceddissociation (LID), electron capture dissociation/electron transfer dissociation(ECD/ETD), infrared multiple photons dissiociation, black body irraditiondissociation and PQD fission technique from Finnigan.