Ion Mobility
Mostrando 1-12 de 105 artigos, teses e dissertações.
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1. TÉCNICAS AVANÇADAS PARA A DIFERENCIAÇÃO DE ISÔMEROS POR ESPECTROMETRIA DE MASSAS
Mass spectrometry (MS) is a powerful and widespread technique but is inherently uncapable to differentiate species with same m/z ratio. For this reason, many classical approaches were developed based on differential fragmentation patterns in tandem MS. More recently, new techniques for isomer identification in MS were developed, and we highlight the photodis
Quím. Nova. Publicado em: 2020-09
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2. ANALYSIS OF THE BASELINE DRIFT ARTIFACT IN HADAMARD TRANSFORM SEPARATION TECHNIQUES
The baseline drift artifact (BDA), namely, the baseline bias between the Hadamard transform (HT) spectrum and the signal averaging (SA) spectrum was unfortunately found in the HT pulsed separation techniques, which makes the HT analytical chemistry face the challenge of non-stability and unreliability. In order to find out the origin and eliminate the BDA ph
Quím. Nova. Publicado em: 2020-01
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3. Analysis of Isomeric Cannabinoid Standards and Cannabis Products by UPLC-ESI-TWIM-MS: a Comparison with GC-MS and GC × GC-QMS
The Cannabis sativa L. plant has a complex chemical composition, containing various chemical compounds such as terpenes, sugars, hydrocarbons, steroids, flavonoids, and amino acids. Few works have attempted to identify the constitutional isomers of cannabinoids that are found in the plant. The present study reported the analysis of seven cannabinoid standard
J. Braz. Chem. Soc.. Publicado em: 2019-01
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4. A Systematic Procedure to Develop a Capillary Electrophoresis Method Using a Minimal Experimental Data
The choice of an appropriate background electrolyte (BGE) and its components for capillary electrophoresis analysis is the main step in capillary electrophoresis method development. The use of an inadequate co-ion component could lead to asymmetrical peaks and selecting an inappropriate counter-ion could affect the buffer capacity and the pH of the BGE, lead
J. Braz. Chem. Soc.. Publicado em: 2016-11
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5. Rapid and Highly Sensitive Determination of Melamine in Different Food Samples by Corona Discharge Ion Mobility Spectrometry after Dispersive Liquid-Liquid Microextraction
In this work, for the first time, a highly sensitive method based on dispersive liquid-liquid microextraction coupled with positive corona discharge ion mobility spectrometry as a fast and inexpensive technique has been evaluated for the direct determination of melamine. The effective parameters influencing the microextraction efficiency, such as pH, the pro
J. Braz. Chem. Soc.. Publicado em: 2016-09
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6. Propiedades eléctricas en membranas de complejos electrolitos poliméricos PVA-OH/LI2SO4/PEG400
Lithium ion conducting polymer electrolytes based on polyvinyl Alcohol (PVA-OH) complexed with salt Li2SO4 and different weight percent ratios of PEG400 plasticizer have been prepared by solution cast technique using deionized water as solvent. The thermogravimetric analysis (TGA) showed that the thermal stability of the materials depended on the plasticizer
Polímeros. Publicado em: 2014
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7. Aplicação de novos materiais em transistores de efeito de campo ferroelétricos
In this work, we investigated the electrical properties of the polyelectrolyte PSS in its sodium form (PSS-Na, Polystyrene sulfonic in the sodium form) and acid form (PSS-H, polystyrene sulfonic in the acid form) and also doped with Fe3+ for application in Ferroelectric Field Effect Transistors (Fe-FET). The PSS-Na was acquired from Aldrich and PSS-H was obt
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 27/07/2012
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8. Uso de espectrometria de massas e mobilidade iônica na caracterização de peptídeos provenientes de experimentos de ligação cruzada / Mass spectrometry and ion mobility in the characterization and of peptides from protein cross-linking experiments
There are several advantages associated with the use of mass spectrometry (MS) applied to structural studies of proteins, such as unlimited mass of target protein or protein complex, very low time and sample consumption, ease of manipulation and interpretation of the data obtained. In chemical cross-linking coupled to MS, bifunctional reagents (cross-linkers
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 10/03/2011
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9. Threshold shifting of nmos transitions by arsenic ion implantation prior to gate oxidation
This paper reports on the threshold adjustment of NMOS transistors by arsenic ion implantation in the channel region directly into bare silicon just before the gate oxidation. Experimental results showed very good uniformity and reproducibility of the threshold voltages, low body effect, and high mobility values.
Publicado em: 2011
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10. Improved Ge surface passivation with ultrathin SiO/sub x/ enabling high-mobility surface channel pMOSFETs featuring a HfSiO/WN gate stack
To realize high-mobility surface channel pMOSFETs on Ge, a 1.6-nm-thick SiOX passivation layer between the bulk Ge substrate and HfSiO gate dielectric was introduced. This approach provides a simple alternative to epitaxial Si deposition followed by selective oxidation and leads to one of the highest peak hole mobilities reported for unstrained surface chann
Publicado em: 2011
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11. A espectrometria de massas e as bio-moleculas : relação estrutura/reatividade de peptideos por reações ion/molecula e mobilidade de ions e busca de novos biomarcadores em clinica medica por imageamento quimio-seletivo de tecidos / Mass spectrometry and bio-molecules : structure-reactivity relation of peptides by ion/molecule reactions and ion mobility and search for new biomarkers in clinical medicini for chemo-selective imaging of tissues
The aim of this doctoral project was to study new applications of mass spectrometry (MS) to bio-molecules by using new techniques and recent approaches room pressure, with the goal of obtaining a more rapid and selective identification of an AA in a peptide sequence. Three-dimensional forms of the peptides and their fragment ions formed (a, b and y), were al
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 02/06/2010
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12. Mobilidade ionica acoplada a espectrometria de massas : interferencia de parametros do drift gas na resolução de anilinas substituidas e determinação da mobilidade intrinsica de agregados de liquidos ionicos / Ion mobility mass spectrometry : interference of drift gas parameters on the resolution of substituted anilines and determination of intrinsic mobility of ionic liquids aggregates
Ion mobility spectrometry separates ions with different sizes or spacial conformations in gas phase according to the time they take to travel through a gas under the influence of an electrical field. Coupling this technique to mass spectrometry provides an extremely versatile tool, able to investigate molecular structure and separate complex samples, includi
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 24/02/2010