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oe1(光电查) - 科学论文

5 条数据
?? 中文(中国)
  • Determination of liquid egg composition using ATR-FTIR spectroscopy and chemometrics

    摘要: BACKGROUND: The use of liquid whole egg (LWE) in food industry as a substitute for shell eggs has been on the increase lately. Since the composition of LWE can easily be changed, determination of protein, lipid, moisture, and total soluble solid (TSS) contents of LWE has also gained importance. Traditional methods usually require more time and effort, and the use of toxic chemicals for sample preparation, where more efficient techniques (faster, cheaper, and more reliable) are needed. In this concern, a novel technique that determines LWE components using ATR-FTIR spectroscopy with partial least square regression (PLS) is presented in this study. RESULTS: The actual values of LWE components were detected by applying reference methods. The accuracy of PLS model was demonstrated by comparing the obtained predictions with the actual values of the component. High coefficients of determination values, which are 0.950, 0.992, 0.994, and 0.972, were achieved for protein, lipid, moisture, and TSS validation data sets, respectively. The error values, namely RMSEC, RMSECV, and RMSEP, were obtained in the range of 0.404-0.978, 0.57-1.82, and 0.83-1.84, respectively. CONCLUSION: ATR-FTIR spectroscopy coupled with chemometrics can provide a rapid and sensitive method for quality control of liquid egg composition.

    关键词: chemometrics,composition,Liquid whole egg,ATR-FTIR spectroscopy,reference method

    更新于2025-09-23 15:23:52

  • Dynamic Diffusion of Disperse Dye in a Polyethylene Terephthalate Film from an Infrared Spectroscopic Perspective

    摘要: The di?usion behavior of a typical disperse dye, disperse red 9 (DR 9), in the polyethylene terephthalate (PET) ?lm at di?erent temperatures was investigated by attenuated total re?ection?Fourier transform infrared spectroscopy and 2D correlation spectroscopy (2Dcos) analyses. According to the Fickian di?usion model, the calculated di?usion coe?cients of DR 9 in the PET ?lm at di?erent temperatures were observed to increase with temperature, which might be attributed to the increased free volume and thermal motion in the PET matrix and the rapid movement of DR 9 molecules at higher temperatures. In-detail analysis of the di?usion spectra discerned various kinds of molecular interactions, including intramolecular hydrogen bonding interactions of DR 9 and dipole?dipole and π?π interactions between DR 9 and PET. Among these, the dipole?dipole interactions between CO groups of DR 9 and PET occurred ?rst and played a vital role during the di?usion process of DR 9, as deduced from the sequence order of group motions in 2Dcos analysis.

    关键词: ATR-FTIR spectroscopy,2D correlation spectroscopy,polyethylene terephthalate,diffusion,disperse dye

    更新于2025-09-23 15:19:57

  • Ligand Binding-Induced Structural Changes in the M <sub/>2</sub> Muscarinic Acetylcholine Receptor Revealed by Vibrational Spectroscopy

    摘要: M2 muscarinic acetylcholine receptor (M2R) is a prototypical G protein-coupled receptor (GPCR) that responds to acetylcholine and mediates various cellular responses in the nervous system. Here, we used Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopy analyses on M2R reconstituted in lipid membrane to understand the molecular mechanism behind the ligand binding-induced conformational changes. Upon agonist binding, M2R shows large spectral change of amide-I band corresponding to backbone C=O stretch, which likely connects with the receptor activation in lipid environment. These results pave the way to probe effects of different ligand binding on GPCRs using vibrational spectroscopy.

    关键词: ATR-FTIR spectroscopy,GPCR,M2R,Ligand,acetylcholine

    更新于2025-09-12 10:27:22

  • Structural characterization of Argania spinosa Moroccan wooden artifacts during natural degradation progress using infrared spectroscopy (ATR-FTIR) and X-Ray diffraction (XRD)

    摘要: The present work is focused on spectroscopic study of four samples of Argan wooden artifact pertaining to the 17th, 18th, 20th and 21st centuries. The objective is to characterize their unknown structures by the study of their non degraded parts and to investigate changes occurred in their degraded parts due to the natural degradation process. Attenuated total re?ectance Fourier transform infrared spectroscopy gauges the presence of many functional groups related to cellulose I and/or II (OH, C–O–C and –CH2), hemicelluloses (particularly C?O (cid:2)1), and lignin (OH phenolic, Car-O and C?Car) and provides qualitative information on the state of wood alteration by informing on the evolution of new former C?O bands. The degree of conversion to carbonyl group, especially quinone or p-quinone at 1650 cm (cid:2)1, is correlated to lignin degradation, while the absence of the C?O acetoxy absorption is ascribable to occurred deterioration in hemicelluloses, and (cid:2)1. X-ray diffraction determines the presence of two forms of cellulose; amorphous cellulose at 18.5(cid:3) 2θ and predominant crystalline cellulose Iβ at 2θ ? 22.6(cid:3) which characterized by an intense peak. The decrease of crystallinity index values con?rms the deterioration level and obvious changes in crystallinity level. However, the microcrystalline structure appears unaltered because no signi?cant changes were observed for calculated cristallite seize. The obtained results depend on the prolonged time of ageing, natural deterioration phenomena, and wood part (internal or external) that is exposed to degradation. The combination of these two methods is useful for an accurate estimation of the degradation level of argan wood.

    关键词: Chemistry,Argan wood artifact,XRD,Analytical chemistry,Natural product chemistry,Materials Chemistry,Natural degradation,Archaeology,ATR-FTIR spectroscopy,Crystallinity,Lignocelluloses,Structural characterization,Materials Science,Organic chemistry

    更新于2025-09-12 10:27:22

  • Developing infrared spectroscopic detection for stratifying brain tumour patients: glioblastoma multiforme <i>vs.</i> lymphoma

    摘要: Over a third of brain tumour patients visit their general practitioner more than five times prior to diagnosis in the UK, leading to 62% of patients being diagnosed as emergency presentations. Unfortunately, symptoms are non-specific to brain tumours, and the majority of these patients complain of headaches on multiple occasions before being referred to a neurologist. As there are currently no methods in place for the early detection of brain cancer, the affected patients’ average life expectancy is reduced by 20 years. These statistics indicate that the current pathway is ineffective, and there is a vast need for a rapid diagnostic test. Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy is sensitive to the hallmarks of cancer, as it analyses the full range of macromolecular classes. The combination of serum spectroscopy and advanced data analysis has previously been shown to rapidly and objectively distinguish brain tumour severity. Recently, a novel high-throughput ATR accessory has been developed, which could be cost-effective to the National Health Service in the UK, and valuable for clinical translation. In this study, 765 blood serum samples have been collected from healthy controls and patients diagnosed with various types of brain cancer, contributing to one of the largest spectroscopic studies to date. Three robust machine learning techniques – random forest, partial least squares-discriminant analysis and support vector machine – have all provided promising results. The novel high-throughput technology has been validated by separating brain cancer and non-cancer with balanced accuracies of 90% which is comparable to the traditional fixed diamond crystal methodology. Furthermore, the differentiation of brain tumour type could be useful for neurologists, as some are difficult to distinguish through medical imaging alone. For example, the highly aggressive glioblastoma multiforme and primary cerebral lymphoma can appear similar on magnetic resonance imaging (MRI) scans, thus are often misdiagnosed. Here, we report the ability of infrared spectroscopy to distinguish between glioblastoma and lymphoma patients, at a sensitivity and specificity of 90.1% and 86.3%, respectively. A reliable serum diagnostic test could avoid the need for surgery and speed up time to definitive chemotherapy and radiotherapy.

    关键词: glioblastoma multiforme,brain tumour,infrared spectroscopic detection,lymphoma,machine learning,ATR-FTIR spectroscopy

    更新于2025-09-12 10:27:22