Near infra-red spectroscopy

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Non-invasive assessment of pineapple and mango fruit quality using near infra-red spectroscopy

Non-invasive assessment of pineapple and mango fruit quality using near infra-red spectroscopy

Calibration between near infra-red spectroscopy absorbance and Brix of pineapple fruit. The NSAS Norris regression program was applied to varying gap (wavelength change between successive mean values) and segment (absorbance data averaged over a range of wavelengths) sizes for spectral data between 760 and 1300 nm to find the best derivative condition for the multiple linear regression analysis. Spectral data (2-nm resolution) were averaged over 4 ‘segment’ sizes (i.e. for a 20 nm segment, 10 values of the original spectral data set were averaged), and for each of 5 ‘gap’ sizes for correlation analysis of both first and second derivative spectral data against Brix (Table 2). Second derivative data in the majority of cases yielded better correlations than first derivative data. In general, varying segment and gap size had little effect on the correlation coefficient (R) or the wavelength in the correlation. The small change in wavelength (784–790 nm for first derivative data, and 800–806 nm for second derivative data) was not significant considering the resolution of the original data (2 nm). The highest correlation coefficient was obtained with a gap size of 16 nm and a segment size of 20 nm, using the second derivative of absorbance at 1220 nm. However, optimal data smoothing was achieved by the combination of a gap size of 0 and a segment size of 20 nm. Using these parameter settings, the highest correlation coefficient was obtained using the second derivative of absorbance at 802 nm. These settings were therefore used in subsequent analyses (J. Guthrie and K. Walsh unpublished data). In contrast, Kawano et al. (1992) recommended the use of a segment size of 16 nm and a gap size of 4 nm in
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The influence of physiological status on age prediction of Anopheles arabiensis using near infra red spectroscopy

The influence of physiological status on age prediction of Anopheles arabiensis using near infra red spectroscopy

Background: Determining the age of malaria vectors is essential for evaluating the impact of interventions that reduce the survival of wild mosquito populations and for estimating changes in vectorial capacity. Near infra-red spectroscopy (NIRS) is a simple and non-destructive method that has been used to determine the age and species of Anopheles gambiae s.l. by analyzing differences in absorption spectra. The spectra are affected by biochemical changes that occur during the life of a mosquito and could be influenced by senescence and also the life history of the mosquito, i.e., mating, blood feeding and egg-laying events.
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Evaluating preservation methods for identifying Anopheles gambiae s s  and Anopheles arabiensis complex mosquitoes species using near infra red spectroscopy

Evaluating preservation methods for identifying Anopheles gambiae s s and Anopheles arabiensis complex mosquitoes species using near infra red spectroscopy

Near infrared spectroscopy (NIRS) is a tool that has the ability to differentiate siblings of the An. gambiae complex based on the composition of their biochemical components such as water, proteins, lipids and carbohy- drates. NIRS is faster and cheaper than using polymerase chain reaction (PCR), the current gold standard [8], and it has been successfully used to identify the age and spe- cies of fresh and RNAlater®-preserved An. gambiae s.s. and An. arabiensis [9-11]. Given the relative expense of RNAlater® and that the use of NIRS on fresh mosquitoes is limiting in large-scale studies, other preservatives such as ethanol, desiccants (drierite and silica gel), refriger- ation and Carnoy have been studied for preservation of mosquitoes for the purpose of age grading. Among these, desiccants (drierite and silica gel) and refrigeration appeared to be very promising in terms of accuracy and price [12]. Other than RNAlater®, preservation methods have not been evaluated for identifying mosquito species using NIRS. It is important to identify a more affordable preservation method that allows for species differenti- ation from preserved specimens. This is critical for NIRS to become a feasible, low-cost option for researchers working on large-scale projects. The present study aims to test cheaper, more field-friendly preservation methods that can be used in conjunction with NIRS to identify the sibling species of An. gambiae complex, specifically An. gambiae s.s. and An. arabiensis.
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NEAR INFRA RED SPECTROSCOPY FOR QUALITY ASSESSMENT OF INDIAN TRADITIONAL HERBAL MEDICINES: A REVIEW

NEAR INFRA RED SPECTROSCOPY FOR QUALITY ASSESSMENT OF INDIAN TRADITIONAL HERBAL MEDICINES: A REVIEW

Chromatography and Chemical Fingerprints of Herbal Medicines: In general, the methods for quality control of herbal medicines involve sensory inspection (macroscopic and microscopic examinations) and analytical inspection using instrumental techniques such as thin layer chromatography, HPLC, GC–MS, LC–MS, near infrared (NIR), and spectrophotometer, etc. 14 . On the other hand, the methods of extraction and sample preparation are also of great importance in preparing good fingerprints of herbal medicines. As a single herbal medicine may contain a great many natural constituents, and a combination of several herbs might give rise to interactions with hundreds of natural constituents during the preparation of extracts, the fingerprints produced by the chromatographic instruments, which may present a relatively good integral representation of various chemical components of herbal medicines.
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The design, calibration and usage of a solid scattering and absorbing phantom for near infra red spectroscopy.

The design, calibration and usage of a solid scattering and absorbing phantom for near infra red spectroscopy.

where A is the absorbance or the optical density, and s is the base 10 absorption coefficient, often called the specific extinction coefficient, and usually quoted in units of cm' mmol'.[r]

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Workload alerts   using physiological measures of mental workload to provide feedback during tasks

Workload alerts using physiological measures of mental workload to provide feedback during tasks

There are a variety of subjective and objective methods used for measuring mental workload, including primary and secondary task analysis [40], physiological or psycho-physiological techniques [24, 33, 44, 52], as well as user opinions using subjective techniques [23, 31]. The most commonly used method for mid-task workload monitoring in industry, as a form of secondary task analysis, is ISA (Instantaneous Self Assessment) and relies on people self reporting their levels of workload at time intervals. Self reporting in this way is used successfully, but has also been shown to either increase workload or negatively affect task performance itself [55]. In this paper, we evaluate the use of functional Near Infra-Red Spectroscopy (fNIRS) data to give people feedback of their current Mental Workload levels during tasks, as a form of unobtrusive objective feedback, in comparison to ISA as an intrusive subjective self assessment. Such objective measures have become more realistic in natural task conditions, as fNIRS, unlike other brain sensing techniques, is a) particularly resilient to artefacts associated with natural computer usage and b) sensitive to changes in Mental Workload [44, 52]. Further, by presenting feedback about current Mental Workload levels, we also explore initial insights into how participants monitor their own performance, and respond to the feedback.
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Phenylephrine versus ephedrine on cerebral perfusion during carotid endarterectomy (PEPPER): study protocol for a randomized controlled trial

Phenylephrine versus ephedrine on cerebral perfusion during carotid endarterectomy (PEPPER): study protocol for a randomized controlled trial

Discussion: Phenylephrine and ephedrine are two of the most commonly used short-acting agents to increase blood pressure in clinical anesthesiologic practice. Monitoring of middle cerebral artery blood velocity with transcranial Doppler and frontal lobe cerebral tissue oxygenation with near infra-red spectroscopy are part of the standard of care. Furthermore, there are no reports that the three-minute modification in breathing frequency described in the “ intervention ” -section is harmful. Therefore, the risks for participating patients are negligible and the burden minimal.
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Robustness of NIR calibrations for assessing fruit quality

Robustness of NIR calibrations for assessing fruit quality

The robustness of multivariate calibration models, based on near infra-red spectroscopy in a partial transmittance optical geometry, for the assessment of total soluble solids (TSS) of intact rockmelons (Cucumis melo) was assessed. The mesocarp TSS was highest around the fruit equator and increased towards the seed cavity. Inner mesocarp TSS levels decreased towards both the proximal and distal ends of the fruit, but more so towards the proximal end. The equatorial region of the fruit was chosen as representative of the fruit for near infra-red assessment of TSS. The spectral window was optimised at 695 to 1,045 nm, and the data pre-treatment procedures were optimised to second derivative absorbance without scatter correction. The ‘global’ modified partial least squares (MPLS) regression modelling procedure of WINISI (ver. 1.04) was found to be superior with respect to root mean square error of prediction (RMSEP) and bias for model predictions of TSS across seasons,
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Plum-tasting using near infra-red (NIR) technology

Plum-tasting using near infra-red (NIR) technology

There were many contributions in the field of NIR spectroscopy used for assessing some quality parameters of fruits and vegetables; such as: pH, sugar content, firmness, texture parameters, optimum picking date, light penetration of NIR in fruit and bruising (Lammertyn et al ., 2000). To our knowledge, taste is an issue that is not often discussed in the literature.

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Evaluation of catheter-induced tribological damage to porcine aorta using infra-red spectroscopy

Evaluation of catheter-induced tribological damage to porcine aorta using infra-red spectroscopy

Figure 6a shows a comparison of the results obtained from undamaged tissue with the tissue damage experiments using catheter tip 1. From the figure it can be seen that one pass causes very little change in the spectrum, with the most visible changes occurring in the 1250-1350 cm -1 wavenumber range (i.e., Region III) and near the peak at 1170 cm -1 (Region II). After 1 pass only a very limited amount of material has been removed from the surface of the tissue. After 5 passes, the spectrum for the damaged region of porcine aorta is significantly altered and remains the same until 10 drags. It is likely that the damage between these two states occurs in the same layer.
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Studies on the Mineralogical Characterization of Coals of Jharia (District-Dhanbad) Coal Field (Lodna & Bhowrah Coal), by X-Ray Differaction (XRD) and IR Spectroscopic Instrumental Techniques

Studies on the Mineralogical Characterization of Coals of Jharia (District-Dhanbad) Coal Field (Lodna & Bhowrah Coal), by X-Ray Differaction (XRD) and IR Spectroscopic Instrumental Techniques

The IR spectroscopy Technique has found its application in coal research as a complimentary technique to X-ray diffraction and other instrumental methods. Although this technique is used primarily for the identification and quantification of various functional groups (e.g. OH, CH a l, CH 3 , COOH), structural parameters (H ar /H, H al /H, C ar /C) of coal, it is also used to deduce information about the different mineral species present in coal. It may be mentioned here that since the broad band of the organic phases masked the bands from the constituent minerals, the mineral characterization used to be severely handicapped earlier. However, with the finer development in the methodology of low temperature ashing, the efficient and near quantitative elimination of the organic fraction of coal became possible, paving way for the clear mineralogical identification by Infra-red spectroscopy. Thus, Karr et at 13 and Estop et al 14
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Is there evidence for change to collagen within parchment samples after exposure to an X-ray dose during high contrast X-ray microtomography? a multi technique investigation

Is there evidence for change to collagen within parchment samples after exposure to an X-ray dose during high contrast X-ray microtomography? a multi technique investigation

Previous studies have concentrated on the effect of ra- diation on the physical properties of books (i.e. cellulose and paper) [6-9] and very few studies have investigated the effect of radiation on parchment [10-13]. Therefore in this study a number of complementary scientific tech- niques are used to compare parchment samples before and after exposure to X-rays using XMT to ensure no detectable change is observed. The techniques used are Attenuated Total Reflection Fourier Transform Infra-red Spectroscopy (ATR-FTIR), SDS-polyacrylamide gel elec- trophoresis (SDS-PAGE), Near-infrared Spectroscopy (NIR) and X-ray diffraction (XRD). ATR-FTIR allows the observation of the conformational changes in the triple helical structure of collagen, SDS-PAGE is used to assess the molecular integrity of the collagen within the parch- ment, NIR can penetrate further into a sample and is therefore beneficial when investigating parchment as a bulk material and XRD is used to assess the structural integrity of the collagen molecules.
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FOURIER TRANSFORMED INFRA RED SPECTROSCOPY IN BEEPRODUCTS ANALYSIS

FOURIER TRANSFORMED INFRA RED SPECTROSCOPY IN BEEPRODUCTS ANALYSIS

Researchers apply Fourier Transformed Infra Red (FTIR) Spectroscopy as a screening tool for identification and classification of honey from different floral sources. Honey samples were usually scanned in the region 600-4000cm -1 (Tewari, 2005). FTIR can be used in all three regions: near IR, mid-IR and far-IR, each of them having advantages and disadvantages.

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Power Tapping Function in Near Infra Red Region  Based on 45° Tilted Fiber Gratings

Power Tapping Function in Near Infra Red Region Based on 45° Tilted Fiber Gratings

Figure 3. (a) Experimental setup for power tapping measure- ment; (b) The side-tapped (circle) and transmitted (square) power from the fabricated five 45˚-TFGs of different lengths; (c) Images of side-tapped out light when launched with a white (SuperK) and (d) Red light, respectively.

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Functionalization of Two Dimensional MoS2: On the Reaction between MoS2 and Organic Thiols

Functionalization of Two Dimensional MoS2: On the Reaction between MoS2 and Organic Thiols

All previous reports on the reaction between organic thiols and MoS2 showed a similar loss of the νS–H by infra-red spectroscopy, leading to the conclusion that the thiol had reacted wit[r]

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NOVEL APPROACH OF PHARMACEUTICAL CO-CRYSTALS FOR POORLY SOLUBLE DRUGS

NOVEL APPROACH OF PHARMACEUTICAL CO-CRYSTALS FOR POORLY SOLUBLE DRUGS

FT-IR (Fourier Transform Infra-red Spectroscopy) Studies, Differential Scanning Calorimetry (DSC) studies, X-Ray Powder Diffraction (XRPD), Scanning Electron Microscopy [r]

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Stability of cypermethrin against a prepared high surface area magnesium oxide

Stability of cypermethrin against a prepared high surface area magnesium oxide

In this study, the stability of cypermethrin under variously prepared high surface area magnesium oxide effect was studied using Fourier Transform Infra-Red spectroscopy and Gas Chrom[r]

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Synthesis and Characterization of Polypyrrole (PPY) Thin Film by Spin Coating Technique

Synthesis and Characterization of Polypyrrole (PPY) Thin Film by Spin Coating Technique

The Polypyrrole synthesized using chemical polymerization process and thin film coated with Spin coating technique. The film non uniform distribution of particles morphology and structure of PPy confirmed by FTIR, XRD and Raman Spectroscopy techniques. UV-Vis studies showed that the PPy films exhibit absorption peak at 469 nm. The pure PPy thin film shows a thermally activated of conductivity.

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Valorization of liquid chemical wastes of laboratories of hospitals case of
laboratories Anatomy Pathology

Valorization of liquid chemical wastes of laboratories of hospitals case of laboratories Anatomy Pathology

Figures 6 and 7 show the results of the analysis by gaseous chromatography coupled with the spectroscopy of mass of pure toluene and that recovered at 110,5°C respectively represented on figures by GC01 and gc02. It should be noted that the shift of times of retention (RT) between the chromatogram of pure toluene and that of the condensed liquid with 110,5°C during distillation is mainly due to the manual injection products during the chromatography.

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The use of biopolymer of poly(3 hydroxybutyrate) as matrix of urea slow release fertilizer

The use of biopolymer of poly(3 hydroxybutyrate) as matrix of urea slow release fertilizer

The use of biopolymer of poly (3-hydroxybutyrate) [(P(3HB)] as a matrix of urea slow release fertilizer has been carried out. The microencapsulation of urea was conducted using the solvent evaporation method. The ratio of urea-P(3HB) for formula 1, 2, and 3 were of 1-1, 1-2, and 1-3 respectively. Microcapsules were evaluated by Scanning Electron Microscope (SEM), Fourier Transform Infra Red (FTIR) spectroscopy, amount of urea in microcapsule, particle size distribution, release test, and kinetic release of active substance. Results showed that the biopolymer P(3HB) could be used as a matrix of urea slow release fertilizer. There was no chemical interaction between urea and P(3HB) during the process of microcapsules formation. The amount of urea in microcapsules in Formula 1, 2, and 3 were detected of 41.39%, 28.89%, and 24.47% respectively. The microcapsules formed the spherical shape with particle size distribution of urea in microcapsules was ranged from 11.4 to 607 µm. it is also observed that the release kinetics model of the active substance (urea) followed the Korsemeyer-Peppas equation. Statistical assay of One Way ANOVA showed that the use of P(3HB) affect the efficiency of release test significantly (p<0.05) which means that an increase in the concentration of P(3HB ) as matrix could reduce the release of urea from the microcapsules.
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