4/27/09

Near-Infrared Reflectance Spectroscopy–Principal Components Regression Analyses of Soil Properties

Near-Infrared Reflectance Spectroscopy–Principal Components Regression Analyses of Soil Properties

4/23/09

Application of two-dimensional near-infrared (2D-NIR) correlation spectroscopy to the discrimination of three species of Dendrobium

The objective of this paper was to apply two-dimensional (2D) near-infrared (NIR) correlation spectroscopy to the discrimination of three species of Dendrobium. Generalized 2D-NIR correlation spectroscopy was able to enhance spectral resolution, simplify the spectrum with overlapped bands and provide information about temperature-induced spectral intensity variations that was hard to obtain from one-dimensional NIR spectroscopy. The FT-NIR spectra were measured over a temperature range of 30-140°C. The 2D synchronous and asynchronous spectra showed remarkable differences within the range of 5600-4750 cm-1 between different species of Dendrobium. Copyright © 2009 John Wiley & Sons, Ltd.

4/18/09

chemometric

4/17/09

Laboratory and Diagnostic Tests

4/16/09

near infrared books

4/15/09

Development of a Continuous Online Detecting System for Fruits Using Near Infrared Technology

A continuous online NIR inspection system in cooperation with light source, detection unit, reference calibration unit, and controlling unit was developed for detecting internal quality of a fruit. For the system, the spectrum measurement, reference calibration, and sugar content calculation can be automatically controlled by its operation software which developed with LabVIEW graphical programming language. The developed prototype system was used to measure the sugar content of Waxapples and Jujubes online. As well, the prediction model was established by Pentium III (933M Hz) computer in conveying speed of 40 mm/sec. The detection results demonstrated a good prediction capability from the prediction model. Moreover, the value of R2 is higher than 0.850 and the value of SEC is lower than 0.713, respectively. It indicated that the correct prediction percentage is over 84.4% within ±1 °Brix error. It point out a reliable inspection system specific dealing with the agricultural engineering aspect was developed in this study.

4/14/09

FRUIT QUALITY OF VESUVIAN APRICOTS HARVESTED AT DIFFERENT RIPENING STAGES AFTER A COLD-STORAGE PERIOD

The present study aimed to investigate the influence of a cold-storage period on some qualitative parameters of Vesuvian apricot cultivars using destructive and non-destructive methods. Fruit harvest was performed at three different ripening stages, based on visual evaluations of the ground color of fruit skin. Fruit firmness and soluble solids content (SSC) were measured both destructively and non-destructively (Vis/NIR commercial device). Cultivar-specific sub-models were built using an independent fruit sample at-harvest. The same destructive and non-destructive measurements were also performed on fruit samples after a cold-storage period (7 days at 4°C). The robustness of the models was tested in predicting SSC and firmness of both fruit at-harvest and after the storage. SSC models appeared fairly accurate when used on fruit at-harvest and, in most of the cultivars, also on cold-stored fruit. On the other hand, the accuracy of the SSC models dramatically decreased from fruit at-harvest to cold-stored fruit in some of the tested cultivars. The firmness models had a very poor accuracy when used on both at-harvest and cold-stored fruit. Further researches are needed to improve the accuracy of the firmness models and to build more robust SSC models.

4/13/09

Near Infra Red Diode Array Spectrometers for On-Line Applications - An application paper in the field of agriculture using our LowCost NIR-Spectrom

The introduction of affordable NIR diode array spectrometers now make the measurement of several parameters that are critical to product value readily available. Over the last decade we have seen the introduction of several affordable spectrometers using silicon based sensors, in the 200nm to 1100nm range. This has spawned a host of new applications, including at line/ on line measurements for product quality and process control which were not affordable before. With the introduction of this NIR diode array spectrometer in a similar price range as its visible counterparts, we expect to see similar results. Since the product has just been introduced, not many applications have been developed. Preliminary results by Dr. Arnold Schumann, CREC-UFL show that this spectrometer may be used successfully for the determination of N content (protein) and water in citrus leaves. The spectrometer is currently undergoing application development for use in the corn, soybean and feed industries.
This paper also presents the advantages of NIR diode array technology and highlights the performance characteristics of this affordably priced NIR spectrometer.

4/12/09

Laboratory and Diagnostic Tests

4/11/09

Near Infrared Books

4/10/09

50% to 99% off Near Infrared Books

4/9/09

Application of near infrared spectroscopy for estimating available nitrogen in poultry manure compost

The objective of this study was to develop an easy method of estimating available nitrogen in poultry manure compost using near infrared spectroscopy (NIRS). A scanning monochromator was used to obtain the reflectance spectra from 1,100 to 2,500 nm of samples of dried and milled poultry manure compost. Second derivative spectra and multiple regression analysis were used to develop calibration equations for total nitrogen (T-N) and uric acid nitrogen (UA-N). Standard error of prediction (SEP) of the best calibrations for T-N and UA-N were 4.74 mg g−1 and 4.32 mg g−1, respectively. The correlation between available nitrogen, which was obtained using incubation experiments, and UA-N in the compost samples was extremely high (r = 0.99999, SE = 0.61 mg g−1). In conclusion, the estimation of available nitrogen from UA-N values using NIRS is a practical method of analyzing poultry manure compost.

4/8/09

Iowa research aims to help corn silage producers

SECTIONS : REGIONAL NEWS

Iowa research aims to help corn silage producers

Tuesday, March 24, 2009

By Jean Caspers-Simmet

Agri News staff writer

CALMAR, Iowa -- What started as a discussion at last year's Northeast Iowa Dairy Foundation annual meeting grew into a corn silage yield trial last summer. Plans are under way to continue the plot.

"Other than our plot there are no independent yield trials being conducted on corn hybrids for silage in Iowa," said Dale Thoreson, Iowa State University Extension dairy beef and forage specialist at the recent annual meeting of the foundation at the Dairy Center south of Calmar.

After a presentation on applied research at last year's annual meeting, a coalition formed to create a corn silage test plot. The group included Extension officials, Northeast Iowa Community College instructors, Northeast Iowa Dairy Foundation members and several seed corn representatives. NICC was interested in introducing students to plot research. The operations committee for the dairy foundation wanted better information for selecting silage hybrids.

American Organics, Monsanto Seed Group, Mycogen Seeds and Pioneer Hi-Bred International each submitted three hybrids known to be superior for corn silage in 2008. The companies paid for lab analysis at harvest.

The Calmar trial was established on a Fayette silt loam soil, Thoreson said. A randomized complete block design was used with three replications of each hybrid. The trial was planted May 14 and harvested Sept. 12.

Twelve hybrids planted were in 4-row plots. Each was replicated three times.

Harvested plants were weighed on a platform scale. Six stalks from each plot were randomly selected to be chopped in a wood chipper. Samples in plastic bags were transported to Dairyland Laboratories in Arcadia, Wis., where dry matter and NIR analysis was done. Tests included crude protein, acid detergent fiber, neutral detergent fiber, neutral detergent fiber digestibility at 24 and 30 hours, in-vitro dry matter digestibility at 30 hours, starch, fat and lignin.

The laboratory also calculated milk per ton for each hybrid using "Milk2006," a program developed by Randy Shaver at the University of Wisconsin. Milk 2006 approximates animal performance based on a standard cow weight and milk production level. Shaver suggested to Thoreson that they should consider more factors than those used in his program.

"To determine a more accurate hybrid ranking we used Corn Picker for Silage, a partial budget program developed by Mike Allen at the University of Michigan," Thoreson said. "Corn Picker for Silage considers all economically important traits that vary by hybrid for corn silage production."

The dairy foundation received a grant from the Leopold Center for Sustainable Agriculture to help pay for next year's silage plot costs. Thoreson and other researchers will look at how planting a winter rye cover crop reduces wind and water erosion. More companies are interested in getting involved this year.

4/7/09

Forensic Application of Near-Infrared Spectroscopy: Aging of Bloodstains

The age of a bloodstain can be used to establish the time when a crime was committed. As blood ages, deoxyhemoglobin (HbO2) is converted into methemoglobin (MetHb), which is evident by the color change from red to brown. Human blood from vein and capillary vessels was used in this investigation. Samples were prepared by placing blood on substrates such as gauze and glass. Near-infrared (NIR) spectra of the samples were measured periodically at ambient conditions for one month. Changes in the spectra can..

4/5/09

Prediction of important sulphite pulp properties from NIR spectra.

In the pulp and paper industry many important process parameters require time consuming wet chemical analyses. These parameters often describe the pulp quality and are used in process control. The need to replace these with fast, accurate measurements is therefor significant. NIR spectroscopy is one method that has been investigated to predict such parameters in kraft pulp research in recent years. Borregaard Industries Ltd. produces sulphite pulp in a wide range of qualities from Norway Spruce. These pulps are mainly used as raw materials in the manufacture of cellulose derivatives such as cellulose ethers, esters, nitrocellulose and viscose, as well as for microcrystalline cellulose. In the process of transforming wood chips to the desired products, the first steps take place in batch reactors. While the wood chips are being processed in the reactors, there is at present no possibility of measuring the properties of the solid phase contents. Such information would be very useful of when the cook should be ended, and thereby minimize deviation from specifications of unbleached pulp. In the present work NIR spectroscopy has been used to predict kappa number and viscosity in unbleached sulphite pulp. Viscosity is an indirect measure of the chain length of the carbohydrates in the pulp and the kappa number is an indirect method for measuring the remaining lignin content in the pulp. NIR spectra have been measured on both pulp and the accompanying cooking liquor and calibrated against wet chemical analyses of the pulp. The main focus was to use the spectra of the cooking liquor to predict chosen pulp properties. The cooking liquor is like a fingerprint of the pulp contents, and should therefore be a god descriptor of these properties. The best calibration method for this purpose was partial least square regression with one response (PLS1) on the 1st derivatives of the NIR spectra. The prediction models will be further developed and eventually applied in the optimization of the pulping process at Borregaard.

4/4/09

Application of NIR Technology in the Feed Analysis

Materials of feed are the base of the feed, and their qualities ensure the qualityand safety of feed products. In order to control the quality of the materials rapidlyand effectly, the method of near infrared reflectance spectroscopy (NIRS) technologywere appplied in this study. 49 true fish meal samples, 4 adulterated fish meal forsale, 50 soybean meal samples and 50 wheat bran samples were collected and delib-erately adulterated with urea, soybean meal,wheat bran and rapeseed meal respectivelyin 1%, 3%, 5% proportion to make 12 adulterated fish meal samples. The sampleswere scaned at the NIRS region 950-1650 nm respectively.The calibration models todetect whether the fish meal samples were adulterated and to predict the activity ofsoybean meal and conventional chemical compositions in fish meal ,soybean meal andwheat bran were developed using different methods to handle the NIR spectrograms ofthe samples. The results were as follows:1. Using the method of PCR to handle the NIR spectrograms of 56 fish mealsamples,we can discriminate true fish meal samples from adulterated fish meal sampleseasily.Therefore, the NIRS technique can be used as a new technique to detect quicklywhether the fish meal samples adulterated or not. Whereafter, the calibration modelwhich was developed with 44 true fish meal samples was established by the meanPCR combine with Mahalanobis distance. The result of validation showed that themodel which developed under the nine pinecipal factors by SNV was the best one,the number of false discrimination was zero.2. The universal calibration model for rapid estimation of the activity of soybean-meal was established by using the partial least square regression(PLS) and fist derivat-ive multivariate scattering correction mean center.The R~2_(cal) and SECV was 0.916and 0.045.The R~2_(val) and SEP was 0.926 and 0.035.The coefficient of variation(CV) ofrepeatability was 0.09.3. The universal calibration models for rapid estimation of conventional chemicalcompositions in soybean meal samples were established by using the partial least squ-are regression (PLS) combine with the methods of mean center, multivariate scatteringcorrection and derivative.The coefficient of determination in calibration (R~2) and RM-SEC of moisture, crude protein, crude fat,crude ash,crude fiber in soybean meal were 0.9695, 0.9755, 0.9507,0.845, 0.9384 and 0.117, 0.338, 0.271, 0.076, 0.267 respectively.And the coefficient of determination in validation and RMSEP of moisture, crudeprotein, crude fat, crude ash,crude fiber in soybean meal were 0.9327, 0.9533, 0.9847,0.8541, 0.9009 and 0.115, 0.313, 0.221, 0.078, 0.248 respectively.Apart from the crudeash, the other calibrations could meet the required for quantitative analysis.The universal calibration models for rapid estimation of conventional chemicalcompositions in fish meal samples were established by using the same mean. Thecoefficient of determination in calibration (R~2) and RMSEC of moisture, crude protein,crude fat,calcium,total phosphor and salt in fish meal samples were 0.9559, 0.9651,0.9421,0.845, 0.8899, 0.9553, 0.9235 and 0.216, 0.386, 0.288, 0.249, 0.085, 0.135Respectively. And the coefficient of determination in validation and RMSEP of mois-ture, crude protein, crude fat,calcium,total phosphor and salt in fish meal sampleswere 0.9395, 0.908, 0.9101, 0.8353, 0.83, 0.9238 and0.314, 0.827, 0.613, 0.474,0.294, 0.393 respectively. Apart from the calcium and total phosphor, the other calib-rations could meet the required for quantitative analysis.The universal calibration models for rapid estimation of conventional chemicalcompositions in wheat bran samples were established by using the same mean. Thecoefficient of determination in calibration (R~2) and RMSEC of moisture,crude protein,crude fat, crude fiber, crude ash in wheat bran samples were 0.9701, 0.9572, 0.9304,0.9814, 0.9582 and 0.101, 0.123, 0.109, 0.129, 0.105 respectively. And the coefficientof determination in validation and RMSEP of moisture, crude protein, crude fat, crudefibre, crude ash in wheat bran samples were 0.9477, 0.9517, 0.8935, 0.9579, 0.8833and 0.142, 0.148, 0.133, 0.161, 0.114 respectively.All of the calibrations could meetthe required for quantitative analysis.

4/3/09

Simultaneous determination of sulphamethoxazole and trimethoprim in powder mixtures by attenuated total reflection-Fourier transform infrared and

Simultaneous determination of sulphamethoxazole and trimethoprim in powder mixtures by attenuated total reflection-Fourier transform infrarednext term and multivariate calibration

A partial least-squares calibration (PLS) procedure in combination with previous terminfrarednext term spectroscopy has been developed for simultaneous determination of sulphamethoxazole (SMZ) and trimethoprim (TMP) in raw material powder mixtures used for manufacturing commercial pharmaceutical products. Multivariate calibration modeling procedures, interval partial least squares (iPLS) and synergy partial least squares (siPLS), were applied to select a spectral range that provided the lowest prediction error in comparison to the full-spectrum model. The experimental matrix was constructed using 49 synthetic samples and 15 commercial samples. The considered concentration ranges were 400–900 mg g−1 SMZ and 80–240 mg g−1 TMP. Spectral data were recorded between 650 and 4000 cm−1 with a 4 cm−1 resolution by Fourier transform previous terminfrarednext term spectroscopy coupled with attenuated total reflectance (ATR-FTIR) accessory. The proposed procedure was compared with conventional procedure by high performance liquid chromatography (HPLC) using 15 commercial samples containing SMZ and TMP. The results showed that PLS regression model combined to ATR-FTIR is a relatively simple, rapid and accurate procedure that could be applied to the simultaneous determination of SMZ and TMP in routine quality control of powder mixtures. A root mean square error of prediction (RMSEP) of 13.18 mg g−1 for SMZ and 6.03 mg g−1 for TMP was obtained after selection of better intervals by siPLS. Using the proposed procedure it is possible to analyze each sample in less than 3 min considering two replicates (excluding the grinding step). Accuracy was checked by comparison to HPLC method and agreement better than 98.8% was achieved.

4/2/09

Detecting the quality of glycerol monolaurate: A method for using Fourier transform infrared spectroscopy with wavelet transform and modified uninform

Glycerol monolaurate (GML) products contain many impurities, such as lauric acid and glucerol. The GML content is an important quality indicator for GML production. A hybrid variable selection algorithm, which is a combination of wavelet transform (WT) technology and modified uninformative variable eliminate (MUVE) method, was proposed to extract useful information from Fourier transform previous terminfrarednext term (FT-IR) transmission spectroscopy for the determination of GML content. FT-IR spectra data were compressed by WT first; the irrelevant variables in the compressed wavelet coefficients were eliminated by MUVE. In the MUVE process, simulated annealing (SA) algorithm was employed to search the optimal cutoff threshold. After the WT-MUVE process, variables for the calibration model were reduced from 7366 to 163. Finally, the retained variables were employed as inputs of partial least squares (PLS) model to build the calibration model. For the prediction set, the correlation coefficient (r) of 0.9910 and root mean square error of prediction (RMSEP) of 4.8617 were obtained. The prediction result was better than the PLS model with full-spectra data. It was indicated that proposed WT-MUVE method could not only make the prediction more accurate, but also make the calibration model more parsimonious. Furthermore, the reconstructed spectra represented the projection of the selected wavelet coefficients into the original domain, affording the chemical interpretation of the predicted results. It is concluded that the FT-IR transmission spectroscopy technique with the proposed method is promising for the fast detection of GML content.

4/1/09

New background correction approach based on polynomial regressions for on-line liquid chromatography–Fourier transform infrared spectrometry

In the present study a new approach for the chemometric background correction in on-line gradient LC–FTIR is introduced. For this purpose, the spectral changes of the elution mixture during gradient elution were analyzed applying 2D correlation spectroscopy. The fundamentals of the new background correction algorithm, based on polynomial fits calculated from a reference spectra matrix (Polyfit-RSM method) are explained. The Polyfit-RSM approach was applied on blank gradient runs as well as on LC–FTIR data obtained from the injection of a soft drink sample using acetonitrile:water as eluent. Results found were critically assessed and compared to those obtained by two previous background correction methods which are likewise based on the use of a reference spectra matrix (RSM). The Polyfit-RSM method provided lower noise levels throughout the whole spectral range than other alternative background correction methods, an excellent recovery of analyte spectra as well as chromatograms with a low noise level and also free from baseline shifts. A significant finding, which implies a major advantage for the practical applicability of the algorithm, is that the size of the RSMs can be reduced without affecting the accuracy of the correction method.
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