Non-destructive Analysis Of Samples Research Articles

Rapid detection of maize seed germination rate based on Gaussian process regression with selection kernel function

Near-infrared spectroscopy (NIR) detection technology enables nondestructive analysis of samples. To achieve fast detection of maize seed germination rates using NIR spectroscopy, 245 samples of maize seeds from three different varieties were purchased from the market and subjected to artificial aging to obtain maize seeds with varying levels of vigor. NIR spectroscopy was collected for each sample, and germination experiments were performed. The Monte Carlo cross-validation method was employed to eliminate 12 outliers, and the baseline correction method along with multiplicative scatter correction (MSC) was applied to the NIR. Partial least squares (PLS), support vector machine (SVM) models, and Gaussian process regression (GPR) models based on different kernel functions were established for detecting maize germination rates. Through comparison of the results of different models, it was found that the GPR model based on the Matern32 kernel function performed best. The R² values for the training and testing sets of this model were 0.9727 and 0.9599, respectively. Experimental results showed that the Matern32-GPR model exhibited greater stability and superior capability in detecting maize seed germination rates. This method can provide a reference for other applications based on NIR detection.

PATH-43. RAMAN SPECTROSCOPY AS A TOOL IN NEUROSURGERY

Abstract BACKGROUND Raman Spectra have been shown to be sufficiently characteristic to their samples of origin that they can be used in a wide range of applications including distinction of intracranial tumors. While not replacing pathological analysis, the advantage of non-destructive sample analysis and extremely fast feedback make this technique an interesting tool for surgical use. METHODS We sampled intractanial tumors from more than 300 patients at the Centre Hospitalier Luxembourg over a period of three years and compared the spectra of different tumor entities, different tumor subregions and healthy surrounding tissue. We created machine-learning based classifiers that include tissue identification as well as diagnostics. RESULTS To this end, we solved several classes in the intracranial tumor classification, and developed classifiers to distinguish primary central nervous system lymphoma from glioblastoma, which is an important differential diagnosis, as well as meningioma from the surrounding healthy dura mater for identification of tumor tissue. Within glioblastoma, we resolve necrotic, vital tumor tissue and peritumoral infiltration zone.We are currently developing a multi-class classifier incorporating all tissue types measured. CONCLUSIONS Raman Spectroscopy has the potential to aid the surgeon in the surgery theater by providing a quick assessment of the tissue analyzed with regards to both tumor identity and tumor margin identification. Once a reliable classifier based on sufficient patient samples is developed, this may even be integrated into a surgical microscope or a neuronavigation system.

A position sensitive [formula omitted] coincidence technique for sample analysis with the upgraded PANDA device

PANDA (Particles And Non-Destructive Analysis) is measuring system developed for non-destructive analysis of samples for safety, security and safeguards. The capabilities of the PANDA device were expanded by the addition of a thick silicon detector for β particle detection. The upgraded device can now be used for position-sensitive α−γ and β−γ coincidence measurements of various kinds of radioactive samples. The capability of the PANDA device in using the β−γ coincidence technique was tested using a mixed source of 134Cs and 226Ra. In addition, the ability of PANDA to locate nuclides emitting β particles from samples was tested using a combined sample containing a mixed 134Cs and 226Ra source and a pure 226Ra source placed a few centimeters apart from each other. The construction, commissioning and testing of the upgraded PANDA device is discussed.

Non-destructive analysis of samples with a complex geometry by NRTA

A non-destructive technique for the elemental and isotopic analysis.

Fourier-transform infrared (FT-IR) spectroscopy analysis discriminates asymptomatic and symptomatic Norway spruce trees

Conifer trees, including Norway spruce, are threatened by fungi of the Heterobasidion annosum species complex, which severely affect timber quality and cause economic losses to forest owners. The timely detection of infected trees is complicated, as the pathogen resides within the heartwood and sapwood of infected trees. The presence of the disease and the extent of the wood decay often becomes evident only after tree felling. Fourier-transform infrared (FT-IR) spectroscopy is a potential method for non-destructive sample analysis that may be useful for identifying infected trees in this pathosystem. We performed FT-IR analysis of 18 phloem, 18 xylem, and 18 needle samples from asymptomatic and symptomatic Norway spruce trees. FT-IR spectra from 1066 – 912 cm−1 could be used to distinguish phloem, xylem, and needle tissue extracts. FT-IR spectra collected from xylem and needle extracts could also be used to discriminate between asymptomatic and symptomatic trees using spectral bands from 1657 – 994 cm−1 and 1104 – 994 cm−1, respectively. A partial least squares regression model predicted the concentration of condensed tannins, a defense-related compound, in phloem of asymptomatic and symptomatic trees. This work is the first to show that FT-IR spectroscopy can be used for the identification of Norway spruce trees naturally infected with Heterobasidion spp.

Comprehensive radioassays of samples using the PANDA device

The PANDA (Particles And Non-Destructive Analysis) device is a measuring system developed for non-destructive analysis of samples for safety, security and safeguards. It consists of two complementary measurement positions. The position sensitive alpha–gamma coincidence setup of PANDA has been updated with a pile-up rejection circuit. This article demonstrates, using a 241Am source, that this circuit can be used to identify gamma-ray sum peaks in the spectra. The second measurement position reported here hosts a 10-mm2 windowless silicon drift detector that detects electrons and X-rays with a very good energy resolution. An experimental value of 0.30keV for full width at half maximum was obtained at 17.7keV energy (Np X-rays). Conversion electron spectrometry, for example, provides an independent, complementary means to study actinides whose low energy transitions are often highly converted.

A handheld laser scanning confocal reflectance imaging–confocal Raman microspectroscopy system

Confocal reflectance microscopy and confocal Raman spectroscopy have shown potential for non-destructive analysis of samples at micron-scale resolutions. Current studies utilizing these techniques often employ large bench-top microscopes, and are not suited for use outside of laboratory settings. We have developed a microscope which combines laser scanning confocal reflectance imaging and confocal Raman spectroscopy into a compact handheld probe that is capable of high-resolution imaging and spectroscopy in a variety of settings. The compact size of the probe is largely due to the use of a MEMS mirror for beam scanning. The probe is capable of axial resolutions of up to 4 μm for the confocal imaging channel and 10 μm for the confocal Raman spectroscopy channel. Here, we report instrument design, characterize optical performance, and provide images and spectra from normal skin to demonstrate the instrument’s capabilities for clinical diagnostics.

101 LIPID FINGERPRINTING OF OOCYTES AND PRE-IMPLANTATION MOUSE EMBRYOS BY DESORPTION ELECTROSPRAY IONIZATION MASS SPECTROMETRY

Lipids and metabolites can be directly detected from biological samples by desorption electrospray ionization mass spectrometry (DESI-MS). The introduction of morphologically friendly solvent systems allows nondestructive analysis of samples and because of its extractive nature, ion intensities obtained are adequate for profiling microscopic samples. This work reports the individual chemical profiling of mouse oocytes and diverse pre-implantation developmental stages of embryos by DESI-MS. Mice were superovulated with 5 IU pregnant mare serum gonadotropin (PMSG) IP followed 46 h later by 5 IU hCG IP and mated or not for embryo and oocyte recovery, respectively. Mice were killed and their oviducts removed and flushed at different intervals post-hCG to collect oocytes and embryos at different stages of development. Two-cell embryos were also cultured in vitro to obtain additional samples. For MS analysis, samples (n = 63) were taken from the flushing or culture medium, washed briefly in distilled water and placed on a glass slide for same-day analysis. Mass spectra were acquired in the negative ion mode at the mass/charge range of m/z 150 to 1000 using 1:1 (v/v) acetonitrile/DMF as a solvent system in an LTQ linear ion trap mass spectrometer (ThermoFisher Scientific, Pittsburgh, PA). Mass spectra from oocytes (n = 11) as well as zygotes (n = 9), 2-cell (n = 11), 4-cell (n = 1), 8- to 16-cell (n = 19) embryos and blastocysts (n = 12) showed the presence of deprotonated free fatty acids such as palmitic (m/z 255.2), linoleic (m/z 281.2), arachidonic (m/z 303.3) and docosahexanoenic (m/z 327.3), as well as prominent fatty acid dimers in the region of m/z 500 to 650, such as m/z 563.5 (oleic acid dimer) and glycerophospholipids in the m/z 700 to 1000 range. These complex lipids were represented by chlorinated phosphocholines such as PC 34:1, m/z 794.7; phosphatidylinositols such as PI 38:4, m/z 885.8; phosphatidylethanolamines such as PE 38:3, m/z 768.7; and phosphatidylserines such as PS 38:4, m/z 810.7. After analysis, samples observed on the glass slide displayed evident dehydration caused by the action of the organic solvent. Chemical profiling was more difficult for oocytes and blastocysts compared with other developmental stages, probably because of the presence of the intact zona pellucida in oocytes, whereas blastocysts were more prone to lysis during the rapid water wash, leading to a decrease in signal intensity. Optimization of conditions, comparison of MS spectra from a greater number of samples of different developmental stages by multivariate statistics and the influence of in vitro vs in vivo conditions are currently being investigated. Although small molecules have been shown to play a role in the direction of cell fate, the mechanisms involved are poorly understood. Perspectives for the application of this novel DESI-MS technique include the ability to study chemical signatures of hierarchical pluripotency observed during early embryonic development including embryonic stem cell differentiation. Support from the Purdue University Center for Cancer Research Small Grants Program is gratefully acknowledged.

On-line monitoring of fat, dry matter and acrylamide contents in potato chips using near infrared interactance and visual reflectance imaging

The contents of dry matter, oil and acrylamide are some of the most relevant parameters in the quality control of potato chips. Near infrared spectroscopy (NIR) is a common technique for routine analysis of bulk chemistry in different raw materials and products because it allows a fast and non-destructive analysis of samples. The objective of this research was to investigate the possibilities of using on-line NIR monitoring of acrylamide, moisture and oil content in potato chips. Sixty samples of potato chips from individual frying runs were measured on-line using a VIS/NIR interactance line scanner. The same samples were analysed in the laboratory to determine their corresponding moisture, acrylamide and oil contents. The mean VIS and NIR spectra for the 60 samples were modelled against the reference values for acrylamide, fat and dry matter using partial least squares regression (PLSR), and the regression models were validated using full cross-validation. On-line NIR interactance was found to predict fat and dry matter of potato chips with high accuracy, i.e. prediction errors of 0.99 and 0.86% (w/w), respectively. The corresponding correlations between predicted values and reference values were 0.99 and 0.97 for fat and dry matter. For acrylamide an average prediction error of 266 μg/kg was achieved using NIR and VIS signals in combination. The correlation between predicted values and reference values was 0.83 for this model. The system may be used to separate samples with very high acrylamide contents from samples with average to low contents.

PANDA—A novel instrument for non-destructive sample analysis

An instrument known as PANDA (Particles And Non-Destructive Analysis) for non-destructive sample analysis has been designed and built at the Finnish Radiation and Nuclear Safety Authority (STUK). In PANDA the measurement techniques and instruments designed for the basic research are applied to the analysis of environmental samples. PANDA has two vacuum chambers, one for loading samples and the other for measurements. In the measurement chamber there are two individual measurement positions. Currently the first one hosts an HPGe gamma detector and a position-sensitive alpha detector. The second measurement position is intended for precise characterization of found particles. PANDA's data are recorded in event mode and events are timestamped. In the present article the technical design of PANDA is presented in detail. In addition, its performance using depleted uranium particles and an air filter is demonstrated.

Automated two-electrode voltage clamp for medium-throughput studies of ion channels with non-destructive sample analysis

Automated two-electrode voltage clamp for medium-throughput studies of ion channels with non-destructive sample analysis

NIR transmission spectroscopy for rapid determination of lipid and lyoprotector content in liposomal vaccine adjuvant system CAF01

It is of crucial importance to determine the concentration of the different components in the formulation accurately, during production. In this respect, near-infrared (NIR) spectroscopy represents an intriguing alternative that offers rapid, non-invasive and non-destructive sample analysis. This method, combined with multivariate data analysis was successfully applied to quantify the total concentration of lipids in the liposomal CAF01 adjuvant, composed of the cationic surfactant dimethyldioctadecylammonium bromide (DDA) and the immunomodulator α,α′-trehalose 6,6′-dibehenate (TDB). The near-infrared (NIR) detection method was compared to a validated high-performance liquid chromatography (HPLC) method and a differential scanning calorimetry (DSC) analysis, and a blinded study with three different sample concentrations was performed, showing that there was no significant difference in the accuracy of the three methods. However, the NIR and DSC methods were more precise than the HPLC method. Also, with the NIR method it was possible to differentiate between various concentrations of trehalose added as cryo-/lyoprotector. These studies therefore suggest that NIR can be used for real-time process control analysis in the production of CAF01 liposomes.

Characterization of Petroleum Deposits Formed in a Producing Well by Synchrotron Radiation-Based Microanalyses

Tubing strings in producing oil wells are often blocked by solid or semisolid deposits that necessitate costly remedial actions to maintain production. We describe here results obtained by a set of synchrotron radiation-based microanalytical techniques to investigate depth profiles and heterogeneity of organic compounds and metals in a series of deposit samples formed at different depths in blocked tubing strings from an operational oil well. Micrometer-scale synchrotron Fourier transform infrared (FTIR) spectroscopic and X-ray fluorescence (XRF) analyses using facilities at the National Synchrotron Light Source at Brookhaven National Laboratory are presented. Visualization, compositional mapping, high-resolution, and nondestructive analysis of samples are some of the main advantages of applying synchrotron-based microanalytical techniques. The results indicate that the depth profile of deposits formed along the same well varies and is characterized by the following main trends from deeper to shallower samples: (1) amount of deposits increases, a complete tubing plugging occurs at shallower levels; (2) concentration of inorganic components decreases; (3) sulfur-containing compounds in the deposits shift relative abundances from predominantly reduced to predominantly oxidized forms; (4) carbon content and H/C atomic ratio increase, S/C and N/C atomic ratios decrease; (5) higher molecular weight (HMW) n-alkane mixtures (wax components) shift the maximum of their distribution from higher to lower molecular weight mixtures; (6) maximum concentrations of some elements (V, Ba, Ti, and Cr) are found in the deepest samples; (7) elements present in all samples along the depth profile are Ca, Fe, Ni, Cu, Pb, and Br. Three different types of aggregates (10−60 μm) dominated by nonpolar, polar, and mixed polar/nonpolar compounds are identified in the same deposit. Predominantly nonpolar (Type I) aggregates contain long chain alkanes, aromatic compounds, and aliphatic thiols, consistent with the characteristics of “wax” type aggregates. The presence of carboxylic acids distributed irregularly toward the periphery of a FTIR mapped aggregate of this type is indicated. Predominantly polar (Type II) aggregates consist of aromatic structures, sulfur, nitrogen, and oxygen-containing compounds, some aliphatic structures, and water molecules possibly associated with salts. The characteristics of this type of aggregates are consistent with “asphaltene” type aggregates. This type of aggregate is found associated with inorganic (probably carbonate, clay, and/or corrosion) particles. Aggregates with mixed nonpolar/polar character are also observed, indicating possible adsorption of resins and asphaltenes by high molecular weight hydrocarbons. Depth profiles show heterogeneity in metal distribution, most likely reflecting systematic changes in proportions between the metal concentrations associated with the organic and inorganic phases in the deposits. Spatial heterogeneity in metals distribution is found on a scale of a hundred micrometers within the same sample. The study demonstrates the benefits of applying a set of complementary synchrotron-based microanalytical nondestructive methods for characterization of the deposits. The results demonstrate the suitability of the methods for studying organic solid aggregation and petroleum deposition problems, as well as the potential for testing and developing chemical and microbial methods for solid petroleum deposit remediation.

Does a powder surface contain all necessary information for particle size distribution analysis?

The aim of this study was to utilise a new approach where digital image information is used in the characterisation of particle size distributions of a large set of pharmaceutical powders. A novel optical set-up was employed to create images and calculate a stereometric parameter from the digital images of powder surfaces. Analysis was made of 40 granule batches with varying particle sizes and compositions prepared with fluidised bed granulation. The extracted digital image information was then connected to particle size using multivariate modelling. The modelled particle size distributions were compared to particle size determinations with sieve analysis and laser diffraction. The results revealed that the created models corresponded well with the particle size distributions measured with sieve analysis and laser diffraction. This study shows that digital images taken from powder surfaces contain all necessary data that is needed for particle size distribution analysis. To obtain this information from images careful consideration has to be given on the imaging conditions. In conclusion, the results of this study suggest that the new approach is a powerful means of analysis in particle size determination. The method is fast, the sample size needed is very small and the technique enables non-destructive analysis of samples. The method is suitable in the particle size range of approximately 20–1500 μm. However, further investigations with a broad range of powders have to be made to obtain information of the possibilities and limitations of the introduced method in powder characterisation.

Locating the origins of blue and white porcelains using EDXRF

Among the main sites of production of ancient Chinese blue and white porcelains can be included Jingdezhen in Jiangxi Province, the Yuxi and Jianshui Kilns of Yunnan Province and the Pinghe Kiln of Fujian Province. The current work focuses on an elemental characterization of ancient porcelains according to the location of manufacture, also incorporating a similar study of the blue and white porcelains of the Qing dynasty from Wun Yiu in Hong Kong, and modern blue and white porcelains from Germany, Japan and Thailand. Non-destructive analysis of samples of porcelain using energy dispersive X-ray fluorescence (EDXRF) has yielded results in terms of 13 chemical elements, namely, Ti, Mn, Fe, Co, Ni, Cu, Zn, Ga, Pb, Rb, Sr, Y and Zr. Principal component analysis has been performed on the data, allowing representation of the first, second and third principal components of the data in 3 D scatter plots; the results reveal data clusterings which correlate to a high degree with the known sites of origin. The conclusion is that the present method is capable of determining differences in elemental concentrations of blue and white porcelains, and that these differences can be used to locate the originating site of manufacture.

Potential application of UV reflection spectroscopy on solid pharmaceutical formulation analysis

An imaginary complex refraction index (extinction coefficient) has been deduced for a number of common pharmaceutical forms from their specular reflection spectra. It seems that reflectivity technique is preferred to the transmission one in those special case in which non-destructive analysis of samples is requested. Furthermore, the obtained results are independent of solvent effects and sample thickness.

Radioactivity determination of 90Y, 90Sr and 89Sr mixtures by spectral deconvolution

The measurement of 90Y, 90Sr and 89Sr in environmental samples has received considerable attention since the advent of the nuclear era. These three radionuclides are pure beta-ray emitters and a nondestructive sample analysis procedure is not available. It is necessary to use complex radiochemical separation procedures to isolate these radionuclides prior to counting. The result is a significant delay between the sample treatment and the activity determination. A rapid analytical procedure is required to obtain the activity of these radionuclides and would appear to be an important goal. A deconvolution method has been applied to logarithmic spectra obtained with a liquid scintillation spectrometer. In a previous paper, this procedure was applied to samples in which 90Y and 90Sr were in equilibrium. Samples have been assessed in which 90Y activity was higher or lower than 90Sr activity, and medium and low activities were considered. Samples with count rates below ba-ckground were analyzed, and the limits of detection of the procedure were determined. The effects of chemical quench and the different activity ratios were studied. It was shown that this treatment of the beta spectra is adequate and represents a rapid method of determining these radionuclides.

A New Method Of Graphic Representation Of Sample Analysed By XRF

XRF nondestructive sample analysis is very convenient when applied to samples that should not be altered, for example, works of art or archeological pieces. When one has various similar samples of this characteristic, a good sample comparison method is necessary. There are various comparison methods among which the three component graphic representation allows a comparison in a throe element component. In an XRF analysis, a large number of peaks, representing emissions from K and L lines normally appear. When a well calibrated spectrum is provided, the determination of the elements in the samples is relatively simple. However, accuracy is difficult to acheive when results from many samples are to be compared.

Contrôle de la pureté d'échantillons de niobium et de tantale par spectrométrie gamma directe après irradiation au moyen de protons de 10 MeV

Non-destructive analysis of samples of niobium and tantalum has been achieved by activation with 10-MeV protons and γ-ray spectrometry. Niobium and molybdenum have been detected and determined in tantalum, as well as molybdenum and tungsten in niobium. Upper limits of concentration have been established for over thirty other undetected elements; most of these limits are below the p.p.m. level, and some reach the p.p.b. level.