Near Infrared

Abstract: Traumatic brain injury (TBI) is a growing health concern affecting civilians and military personnel.

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Photostructural defects resulting from exposure to intense near-infrared femtosecond radiation is studied in three a-SiO 2 glasses with different impurity levels. The photoinduced defects are studied by UV absorption spectroscopy and are correlated to the structural modifications in the glass matrix through Raman spectroscopy. Information in the dynamics of the defect generation is revealed by the small photon energy of IR femtosecond laser radiation.

We present results of a study of the Galactic ridge X-ray emission (GRXE) in hard X-rays with the IBIS telescope on board INTEGRAL in the region near the Galactic Anticenter (GA) at l = 155 •. We assumed a conservative 2σ upper limit on the flux from the GA in the 25 − 60 keV energy band of 1.25 × 10 −10 erg s −1 cm −2 (12.8 mCrab) per IBIS field of view, or 6.6 × 10 −12 erg s −1 cm −2 (0.7 mCrab) per degree longitude in the 135 • < l < 175 • region. This upper limit exceeds the expected GRXE intensity in the GA direction by an order of magnitude, given the near-infrared (NIR) surface brightness of the Milky Way in this region and the standard hard X-ray-to-NIR intensity ratio for the GRXE, assuming stellar origin. Based on the CGRO/EGRET surface brightness of the Galaxy above 100 MeV as a tracer of the cosmic-ray (CR) induced gamma-ray background, the expected GRXE flux in GA exceeds the measured 2σ upper limit by a factor of 4. Therefore, the non-detection of hard X-ray emission from the GA does not contradict the stellar nature of the GRXE, but is inconsistent with CR origin.

Comparison of the spatial and temporal information retrieved from near-infrared phase and average intensity (DC) data reveals that these data types can play a complementary role in the study of the temporal and spatial features of the optical response associated with brain activation during a finger-tapping test. The optical data have been collected with a frequency-domain tissue imager at two wavelengths (690 and 830 nm) and have been analyzed using standard filtering and folding-average procedures. DC and phase data show different temporal and spatial features. A plausible explanation of the different behavior of DC and phase data has been attempted by using Monte Carlo simulations.

It has been developed a general strategy for the determination of pesticides in agrochemicals by Fourier transform near infrared (FT-NIR) spectroscopy. The methodology is based on previous extraction of the active principles through sonication with acetonitrile and direct determination by transmission measurements, using glass vials as measurement cells and univariate calibration at selected wavenumbers as a function of the pesticide to be analyzed. Chlorsulfuron, metamitron, iprodione, pirimicarb, procymidone and tricyclazole were used as test molecules and data obtained by FT-NIR for 20 samples containing one of these active principles compare well with those found by reference liquid chromatography (HPLC) procedures. In short, FT-NIR provides relative standard deviations between 0.04 and 0.7% and limit of detection values ranging from 0.004 to 0.17 mg g −1 with recovery values between 96.4 and 100.5%. On the other hand, FT-NIR offers a 10 times faster methodology than chromatography ones and an environmentally friendly alternative which reduces the reagent consumption to 1 mL acetonitrile per sample.

We determine temperature effect on the absorption and reduced scattering coefficients (a and s Ј) of human forearm skin. Optical and thermal simulation data suggest that a and s Ј are determined within a temperature-controlled depth of Ϸ2 mm. Cutaneous s Ј change linearly with temperature. Change in a was complex and irreversible above body normal temperatures. Light penetration depth (␦) in skin increased on cooling, with considerable person-toperson variations. We attribute the effect of temperature on s Ј to change in refractive index mismatch, and its effect on a to perfusion changes. The reversible temperature effect on s Ј was maintained during more than 90 min. contact between skin and the measuring probe, where temperature was modulated between 38 and 22°C for multiple cycles While temperature modulated s Ј instantaneously and reversibly, a exhibited slower response time and consistent drift. There was a statistically significant upward drift in a and a mostly downward drift in s Ј over the contact period. The drift in temperature-induced fractional change in s Ј was less statistically significant than the drift in s Ј. ⌬ s Ј values determined under temperature modulation conditions may have less nonspecific drift than s Ј which may have significance for noninvasive determination of analytes in human tissue.

Milling and baking tests were carried out on three transgenic wheat lines and their parental varieties grown in the field at two UK sites. The transgenic and control lines were essentially similar in their milling properties but the subunit 1Ax1 and 1Dx5 transgenes had different effects on breadmaking. The subunit 1Dx5 transgene resulted in a low loaf volume and poor crumb structure when expressed in lines with two or five endogenous HMW subunits, and this was accompanied by a greatly increased elastic modulus of the gel protein fraction. In contrast, the 1Ax1 transgene resulted in improved breadmaking quality and a more modest increase in the gel protein elastic modulus when expressed in the two subunit background. Blending of flour from a line expressing the 1Dx5 transgene with flour from a normal breadmaking wheat variety resulted in decreased breadmaking quality, even at a ratio of 1:9. The difference in the results obtained with the 1Ax1 and 1Dx5 transgenes may relate to the presence of an additional cysteine residue in the protein encoded by the latter, which promotes a more highly cross-linked glutenin network.

The cofactor composition and electron-transfer kinetics of the reaction center (RC) from a magnesium chelatase (bchD) mutant of Rhodobacter sphaeroides were characterized. In this RC, the special pair (P) and accessory (B) bacteriochlorophyll (BChl)-binding sites contain Zn-BChl rather than BChl a. Spectroscopic measurements reveal that Zn-BChl also occupies the H sites that are normally occupied by bacteriopheophytin in wild type, and at least 1 of these Zn-BChl molecules is involved in electron transfer in intact Zn-RCs with an efficiency of >95% of the wild-type RC. The absorption spectrum of this Zn-containing RC in the near-infrared region associated with P and B is shifted from 865 to 855 nm and from 802 to 794 nm respectively, compared with wild type. The bands of P and B in the visible region are centered at 600 nm, similar to those of wild type, whereas the H-cofactors have a band at 560 nm, which is a spectral signature of monomeric Zn-BChl in organic solvent. The Zn-BChl H-cofactor spectral differences compared with the P and B positions in the visible region are proposed to be due to a difference in the 5th ligand coordinating the Zn. We suggest that this coordination is a key feature of protein-cofactor interactions, which significantly contributes to the redox midpoint potential of H and the formation of the charge-separated state, and provides a unifying explanation for the properties of the primary acceptor in photosystems I (PS1) and II (PS2). magnesium chelatase mutant ͉ photosynthetic bacterial reaction center ͉ photosystems I and II ͉ protein-cofactor interaction

It is established for the first time that the spatial distribution of breaking waves on the ocean surface is a multifractal process. This result is based on an analysis of airborne visible and near-infrared imagery of the ocean surface under a limited range of wind speed and fetch. A detailed study of the optical spectra of the images and the cumulative probability structure of the prevalent background shows that the lower-intensity reflective areas follow a Rayleigh probability distribution. By contrast, the higher-intensity pixels associated with the scattered light from foam and breaking waves demonstrate scaling characteristics in both the optical spectra and the cumulative probability distributions. It is demonstrated that the degree to which the whitecaps are singularities on a dark background is described by a Lipschitz exponent c•, which uniquely tags each breaking wave. This identification process, called "fractal" or "singularity filtering", leads to a critical condition c• = 1 tentatively associated with the crossover from active entraining whitecaps to passively dissipating foam. The multifractal representation associated with the degree of singularity is simply a restatement that the imagery is composed of a continuum of sets, where each set consists of those breaking waves at a particular phase in their existence. The fractal spectrum of the image above a threshold is shown to be representable by a fractal generator. Physically, the fractal generator models the energy exchange in a breaking wave field as a flux of energy input from the atmosphere to the wave field cascaded over scales of the order of a kilometer to meters. If the energy flux is further parameterized in terms of the receiving area, an assumption similar to closure techniques used in classical turbulence models, the empirical results symmetrically span Phillips's basic arguments for the energy flux terms controlling a wind-driven sea. 16,179 16,180 KERMAN AND BERNIER: MULTIFRACTAL BREAKING WAVES ! . Ii . i Figure 1. (a), Field of breaking waves observed using a line scanner on board an aircraft flying at about 500 m over the Bay of Fundy. Field of view about 250m 2, resolution was about 0.5m, and optical wavelength was 0.95/•m. (b), Image thresholded to remove reflective Rayleigh component. (c), Image of asubsets (a) 1) identified with nonentraining (foam) areas. (d), Image of a subsets, a < 1, identified with entraining (breaking wave) areas. qualitative way what is observed about breaking waves, even at the risk of stating in some cases the obvious. When the field is imaged either by standard photography [Ross and Cardone, 1974; Smith, 1981; Kennedy and Snyder, 1983] or with side-scanning techniques from underneath the surface [Thorpe and Hall, 1983; Thorpe and Humphties, 1980] or from the air (Figure la) [Kerman and Szeto, 1994], several features of the spatial field of breaking waves are evident. The first feature of breaking waves is their distinct isolated nature: the fact that they are born, mature, and die almost always without affecting or being mod-16,182 K••AN AND BERNIER: MULTIFRACTAL BREAKING WAVES

The Prime Focus Spectrograph (PFS) is a new optical/near-infrared multi-fiber spectrograph design for the prime focus of the 8.2m Subaru telescope. PFS will cover 1.3 degree diameter field with 2394 fibers to complement the imaging capability of Hyper SuprimeCam (HSC). The prime focus unit of PFS called Prime Focus Instrument (PFI) provides the interface with the top structure of Subaru telescope and also accommodates the optical bench in which Cobra fiber positioners are located. In addition, the acquisition and guiding (A&G) cameras, the optical fiber positioner system, the cable wrapper, the fiducial fibers, illuminator, and viewer, the field element, and the telemetry system are located inside the PFI. The mechanical structure of the PFI was designed with special care such that its deflections sufficiently match those of the HSC's Wide Field Corrector (WFC) so the fibers will stay on targets over the course of the observations within the required accuracy.

Despite the importance of litter on forest floor albedo and brightness, previous studies have not documented forest floor albedo or litter cover in any detail. Our objective was to describe the seasonal influence of litter on spectral albedos and nadir reflectances of a forest snowpack in a mixed-hardwood stand in the Sleepers River Research Watershed (SRRW) in Danville, Vermont (37°39′ N, 119°2′ W). Experimental measurements in a nearby open area at the Snow Research Station of the SRRW nearly duplicated the spectral trend observed in the forest. Spectral albedo and nadir reflectance measurements in the visible and near infrared (350–2500 nm) transitioned from a gently curved shape through the visible range (for finer-grained, lightly littered snow) to one having a peak in the red/near-infrared (near 760 nm) as the snowmelt season progressed (for coarser-grained, more heavily littered snow). The snowpack became optically thin as surface litter reached high percentages. A point-in-time digital photographic survey of the late-lying snowpacks of three forest stands and the open showed that median litter cover percentages in the coniferous, deciduous, mixed-forest, and an open area were 17·5, 6·1, 1·2, and 0·04 respectively. A Kruskal–Wallis ANOVA on ranks and pairwise comparisons using Dunn's test indicated that the litter covers of the three forest stands were significantly different with >95% confidence. The snowpack was relatively shallow (<1 m), as is typical for this area of Vermont. From a remote-sensing standpoint, and since shallow snow and increased grain size also lower the visible albedo, we can expect that snowpack litter will cause decreased albedo earlier in the snowmelt season, at deeper snow depths, and will tend to shift the maximum albedo peak to the red/NIR range as the melt season progresses. Published in 2001 by John Wiley & Sons, Ltd.

There is a vast demand for in vivo methods for the detection of skin cancer, one of the most dangerous skin lesions. Use of near infrared Fourier transform (NIR-FT)-Raman spectroscopy virtually eliminates the fluorescence of the normal cell constituents and provides a signal to noise ratio, r SN , large enough to successfully evaluate the spectra using chemometric methods. A novel fiber optic probe for NIR-FT-Raman spectroscopy was used, which allows sterilization and the prevention of hazards due to laser radiation and makes in vivo measurements possible. The Raman spectra of normal skin are dominated by the connective tissue, mainly collagen type I. The Raman spectra of skin with inflammatory diseases show an increased lipid and water content. Kaposi sarcomas show typical features of tumors mainly in the amide III and the protein backbone range. A clear separation of Raman spectra of normal skin from those of benign and malignant neoplasms can be achieved by cluster analysis. However, the unequivocal diagnosis of skin cancer needs investigation of a larger number of more defined skin samples, taking into consideration the concurrent appearance of different skin symptoms like coloring and inflammation. cal fibers are used in Raman endoscopes [14] for measurement.

We investigate the temperature dependence of germanium on silicon p-i-n photodetectors in terms of both dark current density and near-infrared responsivity. The dark current increases by nearly a factor 1.6 every 10 C, consistently with carrier generation in the space charge region. The responsivity has a complex trend, its temperature variation depending on wavelength and on the germanium quality. Detectors with a large defect density in the active layer exhibit a reduced responsivity as the temperature increases.

This paper comprises a comparison between the vegetation response in ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) multispectral optical imagery and possibly equivalent bedrock/regolith/soil response in airborne gamma-ray spectrometry grids, employing a tropical rainforest area in the Brazilian Amazon as a control. The applied technique comprised band ratios using a fixed near infrared band (numerator) divided by individual visible and shortwave infrared bands (denominator). These band ratios were subsequently submitted to principal component analysis, and the high frequency information is smoothed by low pass filtering. The colour compositions selected for interpretation were sharpened by the first principal component of the original ASTER bands through an IHS transform in order to add albedo/texture information lost through band rationing back to the imagery. The products show a plausible coherence with airborne gamma-ray data and field observations, provi...

Polarization-sensitive optical coherence tomography ͑PS-OCT͒ and near-infrared ͑NIR͒ imaging are promising new technologies under development for monitoring early carious lesions. Fluorosis is a growing problem in the United States, and the more prevalent mild fluorosis can be visually mistaken for early enamel demineralization. Unfortunately, there is little quantitative information available regarding the differences in optical properties of sound enamel, enamel developmental defects, and caries. Thirty extracted human teeth with various degrees of suspected fluorosis were imaged using PS-OCT and NIR. An InGaAs camera and a NIR diode laser were used to measure the optical attenuation through transverse tooth sections ͑ϳ200 m͒. A digital microradiography system was used to quantify the enamel defect severity by measurement of the relative mineral loss for comparison with optical scattering measurements. Developmental defects were clearly visible in the polarizationresolved OCT images, demonstrating that PS-OCT can be used to nondestructively measure the depth and possible severity of the defects. Enamel defects on whole teeth that could be imaged with high contrast with visible light were transparent in the NIR. This study suggests that PS-OCT and NIR methods may potentially be used as tools to assess the severity and extent of enamel defects.

Oxygenation measurements are widely used in patient care. However, most clinically available instruments currently consist of contact probes that only provide global monitoring of the patient (e.g., pulse oximetry probes) or local monitoring of small areas (e.g., spectroscopy-based probes). Visualization of oxygenation over large areas of tissue, without a priori knowledge of the location of defects, has the potential to improve patient management in many surgical and critical care applications. In this study, we present a clinically compatible multispectral spatial frequency domain imaging (SFDI) system optimized for surgical oxygenation imaging. This system was used to image tissue oxygenation over a large area (16×12 cm) and was validated during preclinical studies by comparing results obtained with an FDA-approved clinical oxygenation probe. Skin flap, bowel, and liver vascular occlusion experiments were performed on Yorkshire pigs and demonstrated that over the course of the experiment, relative changes in oxygen saturation measured using SFDI had an accuracy within 10% of those made using the FDA-approved device. Finally, the new SFDI system was translated to the clinic in a first-in-human pilot study that imaged skin flap oxygenation during reconstructive breast surgery. Overall, this study lays the foundation for clinical translation of endogenous contrast imaging using SFDI.

catalysts characterized by a wide copper content (0.25 < Cu wt% < 9.0) has been discussed. X-ray absorption near edge spectroscopy, electron spin resonance, and near infrared diffuse reflectance spectroscopy (NIR DRS) techniques and IR spectroscopy of adsorbed NO and CO, have been used to demonstrate that the key mechanism of the oxychlorination reaction is the reduction of CuCl 2 to CuCl following the path 2CuCl 2 + C 2 H 4 → C 2 H 4 Cl 2 + 2CuCl. This reaction holds for the cupric ions in the supported amorphous CuCl 2 phase, with its activity enhanced by a very high degree of dispersion as demonstrated by chemisorption measurements (up to 72%). In contrast Cu(II) cations forming the surface copper aluminate phase are unreactive toward ethylene. A detailed analysis of the IR spectra obtained at liquid nitrogen temperature allows extraction of important information on catalyst support: (i) Cl − anions are hosted on the support surface and their presence enhances the Brønsted acidity of the surface >Al-OH groups; and (ii) >Al 3+ coordinative unsaturated Lewis acidic sites are present on the catalyst. These results point out the possible determinant role of the support in side reactions and coking that are responsible for loss of selectivity and, respectively, catalyst decay during industrial runs.

GNOSIS is an OH suppression unit to be used in conjunction with existing spectrographs. The OH suppression is achieved using fibre Bragg gratings (FBGs), and will deliver the darkest near-infrared background of any ground-based instrument. Laboratory and on-sky tests demonstrate that FBGs can suppress OH lines by 30dB whilst maintaing > 90% throughput between the lines, resulting in a ≈ 4 mag decrease in the background.

Near infrared radiation has been successfully used in scanning vein patterns for biometric applications. While the method has been proven as highly reliable, few studies have been conducted using medium or far infrared radiation to assess the viability of a biometric scanning technique based on different wavelengths. With the constant decrease in prices for thermographic devices, the goal of this research was to determine if far infrared radiation is suitable for vein detection and to develop techniques for image processing and parameter extraction. Efforts have been made to integrate both methods (near and far infrared) in order to unify the data processing algorithms for real acquisitions and to provide enough information for performing visual reconstruction of blood vessels in simulation and database generating applications.

Ultrasensitive, near-infrared (NIR), time-resolved fluorescence is evaluated as a detection method for reading DNA hybridization events on solid surfaces for microarray applications. In addition, the potential of mulitiplexed analyses using time-resolved identification protocols is described. To carry out this work, a NIR time-resolved confocal imager was constructed to read fluorescence signatures from the arrays. The device utilized a 780-nm pulsed diode laser, a single-photon avalanche diode (SPAD), and a high-numerical-aperture microscope objective mounted in an epi-illumination format. Due to the small size of the components that are required to construct this imager, the entire detector could easily be mounted on high-resolution translational stages and scanned over the stationary arrays. The instrument response function of the device was determined to be 275 ps (fwhm), which is adequate for measuring fluorophores with subnanosecond lifetimes. To characterize the system, NIR dyes were deposited directly on different substrate materials typically used for DNA microarrays, and the fluorescence lifetimes of two representative dyes were measured. The fluorescence lifetime for aluminum tetrasulfonated naphthalocyanine was found to be 1.92 ns, and a value of 1.21 ns was determined for the tricarbocyanine dye, IRD800, when it was deposited onto poly(methyl methacrylate) (PMMA) and measured in the dry state. Finally, the imager was used to monitor hybridization events using probe oligonucleotides chemically tethered to a PMMA substrate via a glutardialdehyde linkage to an aminated-PMMA surface. The limit of detection for oligonucleotides containing a NIR fluorescent reporter was determined to be 0.38 molecules/µm 2 , with this detection limit improving by a factor of 10 when a time-gate was implemented. Fluorescence lifetime analysis of the hybridization events on PMMA indicated a lifetime value of 1.23 ns for the NIR-labeled oligonucleotides when using maximum-likelihood estimators.

The processing of polymers may be accompanied by oxidation and elimination reactions that affect the quality of the final product. In reactive processing, polymerisation occurs in the extruder or autoclave and the extent of reaction becomes an important process variable. The monitoring of these chemical changes in real-time so that processing may be optimised requires the use of analytical methods such as fibre-optic Near Infrared (NIR) spectroscopy. In this paper the requirements and limitations for this and related spectroscopic probes are described and novel approaches based on infrared emission and transient infrared transmission spectroscopy (TIRTS) are discussed. To cite this article: G.

The near infrared analysis (NIRA) approach was studied to examine its capability for predicting spectral feature soil properties from the reflectance curves in the near infrared (NIR) region (1-2.5 um) of arid and semiarid soils. High-resolution diffuse reflectance spectra (3113 spectral points) in the NIR region were recorded for 91 soil samples from Israel. Six soil properties (clay content, specific surface area, cation-exchange capacity, hygroscopic moisture, carbonate content, and organic matter content) were measured by routine methods employed in soil laboratories. An empirical model to predict each property from its spectral signature was developed by adapting the NIRA technique. Several data manipulations were used to obtain optimum performance. The optimum performance of all properties was found to be between 25 and 63 spectral points. Strong support for the NIRA capability was provided by its ability to examine most of the spectral assignments. A slight bias was observed for the prediction of both organic matter and hygroscopic moisture, suggesting that more attention in the prediction of these constituents is required. It was concluded that NIRA is a promising method for rapid and nonrestrictive analysis of soil materials, and further study of the synergism between NIRA and soil materials is recommended. N EAR-INFRARED ANALYSIS is a laboratory approach that analyzes the diffuse reflectance radiation with regard to a material's chemistry (Stark et al., 1986). This methodology was developed 25 yr ago for rapid analysis of moisture in grains (Ben-Gera and Norris, 1968). Today, NIRA is well accepted and widely used in many other disciplines (Davies and Grant, 1987; Norris, 1988). This method is known for its rapidity, convenience, simplicity, accuracy, and ability to analyze many constituents at the same time (Stark et al., 1986). In

High-performance coatings for micromechanical mirrors were developed. The high-reflective metal systems can be integrated into the technology of MOEMS, such as spatial light modulators and microscanning mirrors from the near-infrared down to the vacuum-ultraviolet spectral regions. The reported metal designs permit high optical performances to be merged with suitable mechanical properties and fitting complementary metal-oxide semiconductor compatibility.

... Marcel Babin1 and Dariusz Stramski Marine Physical Laboratory, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, California 92093-0238 ... Source Clay Minerals Repository, University of Missouri (ref. no. ...

The content of phenolic compounds determines the state of phenolic ripening of red grapes, which is a key criterion in setting the harvest date to produce quality red wines. Wine phenolics are also important quality components that contribute to the color, taste, and mouth feel of wines. Spectroscopic techniques (e.g., near and mid infrared) offer the potential to simplify and reduce the analytical time for a range of grape and wine analytes. It is this characteristic, together with the ability to simultaneously measure several analytes in the same sample at the same time, which makes these techniques very attractive for use in both industry and research. The objective of this mini review is to present examples and to discuss different applications of visible (VIS), near infrared (NIR) and mid infrared (MIR) to assess and measure phenolic compounds in grape and wines.

A simple apparatus for time-correla ted single photon counting (TCSPC) m easurements in the near-infrared (near-IR) region for scanning-type applications has been constructed and examined. The apparatus consisted of ® ve m ajor com ponents including a pulsed diode laser source (lasing wavelength 5 780 nm; rep etition rate 5 80 MHz; power 5 5 mW ; pulse width 5 150 ps), an integrated m icroscope, a large-photoactive-area avalanche photodiode (APD), a TCSPC PC-board including the electron ics, and a Windows-based software package for accu mulating the¯uorescen ce decay pro® les. The instrument response function (IRF) of this assembly was found to be 460 ps, which is adequate for measuring lifetim es with t f $ 500 ps. Due to the sm all size of the device, it also allowed implem entation into scanning experim ents where lifetimes were measured. To dem onstrate this capability, we scanned a three-well microscope slide containing a near-IR dye. The decay pro® le of the near-IR dye, aluminum 2,3-naphthalocyanine, was collected and analyzed to obtain its lifetime, which was found to be 2.73 ns, in close agreement with the literature value for this particular dye. In addition, a three-dim ensional plot showing the decay pro® les (tim e vs. photocounts) and scan position of aluminum 2,3-naphthalocyaninē uorescence was acquired by scanning the m icroscope head over this three-well glass slide. In the scanning m ode, the IRFs as well as the decays of the dyes were found to be very stable. The device dem onstrated a concentration detection sensitivity of 0.44 nM; however, the dynamic range was limited due to the slow tim e constant (passive quenching) associated with the APD.

Sustainable forest production demands a continuous supply of high quality seeds for the production of seedlings in the nursery or for direct sowing. Here, we demonstrated the potential of near infrared spectroscopy as a rapid technique to discriminate viable and empty seeds of Pinus patula Schiede & Deppe. Near infrared spectra were collected from single seeds in transmittance and reflectance modes. To discriminate viable and empty seeds, multivariate classification models were developed with partial least squares (PLS) regression using the digitized spectra as a regressor and a y-vector of artificial values (1 for viable and −1 for empty seeds) as a regressand. Viable and empty seeds were perfectly distinguished by PLS models computed on full and selected transmittance spectroscopy data, while those derived from ‘full’ NIR reflectance spectra recognized 96 % of viable and 88 % of empty seeds. Analyses made on selected NIR reflectance spectra improved the classification rate of empty seeds to 100%. Difference spectra and PLS weights indicated that the origin of spectral differences between viable and empty seeds was attributed to differences in fatty acids and proteins that were totally absent in empty seeds. The result shows the prospect of developing rapid filter-based sorting equipment that can easily be automated.

A microcontrolled, portable and inexpensive photometer is proposed. It uses a near infrared light emitting diode (NIR LED) as radiation source, a PbSe photoresistor as infrared detector and a programmable interrupt controller (PIC) microcontroller as control unit. The detector system presents a thermoresistor and a thermoelectric cooling to control the detector temperature and keep the noise at low levels. The microcontroller incorporated total autonomy on the proposed photometer. As its components are inexpensive and of easy acquisition, the proposed NIR LED-photometer is an economical alternative for chemical analyses in small routine, research and/or teaching laboratories. By being portable and microcontrolled, it also allows carrying out field chemical analyses. The instrument was successfully applied on the screening analysis to verify adulteration in gasoline samples.

Vanadylphthalocyanine with four naphthoxy pendant groups on the periphery was prepared by cyclotetramerization of 4-(2-naphthoxy)phthalonitrile. The new compound was characterized by elemental analyses, Mass, IR and UV-Vis spectral data. The electronic spectra exhibit an intense absorption peak at 703 nm indicating the C 4v symmetry of VOPc. VO 2+ ion in this structure was studied using electron paramagnetic resonance (EPR) technique at room temperature. The covalent bonding parameter for VO 2+ ion and Fermi contact term were calculated using the principal axis values of the g and hyperfine splitting obtained from powder EPR spectrum.

We report the first multi-filter set of absolutely-calibrated nearinfrared images of Uranus, its rings, and three major satellites -. Titania, Ariel, and Miranda. Along with imagery utilizing the canonical K filter bandpass (effective wavelength 2.20 pm), absolutely calibrated images of the Uranian system are presented for the first time for three additional filter bandpasses: J (1.27 pm), H (1.62 pm) and in a narrow bandpass (0.1 p m full-width-at-half-maximum) centered at 1.73 p m (hereafter designated H') particularly diagnostic of C-H stretch vibrational absorptions common in hydrocarbons. Multi-filter-derived spectra of the southern ring ansa including the bright apoapse of the dominant E ring show no absorptions due to condensable volatiles, including water, ammonia, and light (high H:C) hydrocarbons. Plausible near-infrared spherical geometric and single-scattering particle albedos consistent with Voyager-derived phase functions range from 0.069 to 0.102 and 0.030 to 0.037, respectively. These are approximately 50% greater than visible values, consistent with the optical properties of charcoal, carbonaceous chondrite material, and the darkside of Iapetus, and consistent with the hypothesis that a primary component of the ring particles is high stoichiometric ratio C:H organics produced by charged-particle and/or photochemical weathering of methane clathrate and/or hydrocarbon ice material originating from nearby moonlets. Additional components consistent with the ring spectrum include silicates such as pyroxene, but not olivine. Analytical modelling of the ring structure indicates &-ring near-infrared opacities of 0.37 f 0.05 and 1.8 f 0 . 3 at apoapsis and periapsis, respectively. Ariel is more than 25% brighter than Miranda and 15% 3 brighter than Titania at all near-infrared wavelengths. Comparisons with UV-visible spectra by Karkoschka (1997, Icarus 125, 348-363) show consistency with the hypothesis that the water-ice surfaces of Titania and Ariel are contaminated with low-reflectance, near-ir-reddened substances similar to the weathered high C:H material postulated for the Uranian ring system. The relatively blue, near-infrared dark surface of Miranda (fulldisk near-infrared albedo of -0.22 at 2.40 phase angle) exhibits the greatest water ice absorption band-depth and the largest H-and K-filter brightness surge measured among the Uranian satellites, consistent with

Visible (VIS) and near infrared (NIR) reflectance spectroscopy combined with multivariate data analysis were explored to predict fibre diameter in both clean and greasy Merino wool samples. Fifty clean and 400 greasy wool samples were analysed. Samples were scanned in a large cuvette using a NIRSystems 6500 monochromator instrument by reflectance in the VIS and NIR regions (400 to 2500 nm). Partial least square (PLS) regression was used to develop a number of calibration models between the spectral and reference data. Different mathematical treatments were used during model development. Cross validation was used to assess the performance and avoid overfitting of the models. The NIR calibration models gave a coefficient of determination in calibration (R2) &gt; 0·90 for clean wool samples and a R2 &lt; 0·50 for greasy wool samples. The values for the residual predictive value, RPD (ratio of standard deviation (s. d.) to the root mean square of the standard error of cross validation (...

We present current and near-term uses of high-power fiber lasers and amplifiers for NASA science and spacecraft applications. Fiber lasers and amplifiers offer numerous advantages for the deployment of instruments on exploration and science remote sensing satellites. Ground-based and airborne systems provide an evolutionary path to space and a means for calibration and verification of space-borne systems. NASA fiber-laser-based instruments include laser sounders and lidars for measuring atmospheric carbon dioxide, oxygen, water vapor and methane and a pulsed or pseudo-noise (PN) code laser ranging system in the near infrared (NIR) wavelength band. The associated fiber transmitters include high-power erbium, ytterbium, and neodymium systems and a fiber laser pumped optical parametric oscillator. We discuss recent experimental progress on these systems and instrument prototypes for ongoing development efforts.

Crop protection seldom takes into account soil heterogeneity at the field scale. Yet, variable site characteristics affect the incidence of pests as well as the efficacy and fate of pesticides in soil. This article reviews crucial starting points for incorporating soil information into precision crop protection (PCP). At present, the lack of adequate field maps is a major drawback. Conventional soil analyses are too expensive to capture soil heterogeneity at the field scale with the required spatial resolution. Therefore, we discuss alternative procedures exemplified by our own results concerning (i) minimally and noninvasive sensor techniques for the estimation of soil properties, (ii) the evidence of soil heterogeneity with respect to PCP, and (iii) current possibilities for incorporation of high resolution soil information into crop protection decisions. Soil organic carbon (SOC) and soil texture are extremely interesting for PCP. Their determination with minimally invasive techniques requires the sampling of soils, because the sensors must be used in the laboratory. However, this technique delivers precise information at low cost. We accurately determined SOC in the near-infrared. In the mid-infrared, texture and lime content were also exactly quantified. Non-invasive sensors require less effort. The airborne HyMap sensor was suitable for the detection of variability in SOC at high resolution, thus promising further progress regarding SOC data acquisition from bare soil. The apparent electrical conductivity as measured by an EM38 sensor was shown to be a suitable proxy for soil texture and layering. A survey of arable fields near Bonn (Germany) revealed widespread within-field heterogeneity of texture-related ECa, SOC and other characteristics. Maps of herbicide sorption and application rate were derived from sensor data,

Novel electronic materials play an ever-increasing role in technological applications. They cover a rather broad spectrum of materials that exhibit exotic transport and magnetic properties. These include superconductors, narrow band gap semiconductors, electronically active polymers, colossal magneto resistive systems, nanoscale electronic materials, and Fullerenes, to name a few. Understanding the interplay between strong electronic correlations and structural properties of these materials is important. In this communication, we report the growth and preliminary characterization of single crystal Cerium based intermetallic compounds that are known to show superconductivity at Tc = 2.3K.

This paper discusses the application and adaptation of two existing operational algorithms for land surface emissivity (ε) retrieval from different operational satellite/airborne sensors with bands in the visible and near-infrared (VNIR) and thermal IR (TIR) regions: 1) the temperature and emissivity separation algorithm, which retrieves ε only from TIR data and 2) the normalized-difference vegetation index thresholds method, in which ε is retrieved from VNIR data.

A simple, economic diode laser based cavity ringdown system for trace-gas applications in the petrochemical industry is presented. As acetylene (C 2 H 2 ) is sometimes present as an interfering contaminant in the gas flow of ethylene (ethene, C 2 H 4 ) in a polyethylene production process, an on-line monitoring of such traces is essential. We investigated C 2 H 2 -C 2 H 4 mixtures in a gas-flow configuration in real time. The experimental setup consists of a near-infrared external cavity diode laser with an output power of a few mW, standard telecommunication fibers and a home-made gas cell providing a user-friendly cavity alignment. A noise-equivalent detection sensitivity of 4.5 × 10 −8 cm −1 Hz −1/2 was achieved, corresponding to a detection limit of 20 ppbV C 2 H 2 in synthetic air at 100 mbar. In an actual C 2 H 2 -C 2 H 4 gas-flow measurement the minimum detectable concentration of C 2 H 2 added to the C 2 H 4 gas stream (which may already contain an unknown C 2 H 2 contamination) increased to 160 ppbV. Moreover, stepwise C 2 H 2 concentration increments of 500 ppbV were resolved with a 1-min time resolution and an excellent linear relationship between the absorption coefficient and the concentration was found.

The relationship between human consciousness and oxygen saturation (rSO 2 ) in cerebral tissue under high +Gz stress was non-invasively monitored by near-infrared multiple wavelength spectroscopy (NIRS). We studied the drop in rSO 2 levels in human subjects during exposure to various head-to-foot acceleration (+Gz) profiles. These profiles included sustained +Gz plateaus and repeated short duration +Gz pulses of varying duration. The end point in this study was +Gz-induced loss of consciousness (G-LOC). The rSO 2 levels under normal (asymptomatic), almost loss of consciousness (A-LOC) and G-LOC conditions were recorded. Correlations among decrease in rSO 2 , +Gz pulse duration, +Gz stress level and incapacitation time (ICAP) after G-LOC were also investigated. It was found that once rSO 2 fell to a certain level, G-LOC occurred. This threshold was repeatable and independent of the +Gz level or duration. It was also observed that the total ICAP after G-LOC was dependent on the length of time that rSO 2 remained below the G-LOC threshold level, i.e. the longer the rSO 2 level remained below the G-LOC induction level, the longer the subject remained unconscious. These results may prove to be useful in designing closed loop control systems for personal protective gear for pilots of high performance aircraft.

The transient reflectivity of bismuth crystal excited by a 45 fs laser pulse in the near-infrared range has been recovered with an accuracy of 10 −5 , at initial sample temperatures ranging from 50 to 510 K, and at pump fluences from 2 mJ/ cm 2 to 21 mJ/ cm 2. The coherent phonon excitation and decay processes were imprinted into the time-dependent reflectivity and this allows us to uncover the temporal phonon history preceding the structural transformation of solid Bi. Analysis showed that the first coherent atomic displacement was produced by the polarization force and the electron pressure force during the laser pulse, and that manifests itself by a negative change in the reflectivity. The frequency of the subsequent reflectivity oscillations was chirped, redshifted from the initial value due to the lattice heating. The amplitude decreased gradually while electrons transferred their energy to the lattice. Heating and thermal expansion of the lattice transformed the initially coherent harmonic vibrations of atoms into strongly nonlinear chaotic motion that signifies the onset of disordering of the solid. This process was identified through measurement of the damping rate of the reflectivity oscillations and interpretation of this rate as the decay rate of an optical phonon into two acoustic phonons. The analysis of the reflectivity oscillations provides evidence that the overheated solid experiences only the onset of the solid-liquid phase transition but did not proceed into the liquid phase. General relations between the laser-exerted forces, the atomic motion, and the optical parameters were established. The proposed theory reproduces well the measured transient reflectivity across a wide range of crystal temperatures and laser excitation fluences.

The emission spectrum measured in the middle infrared (IR) band from the plume of a rocket can be used to identify rockets and track inbound missiles. It is useful to test the stealth properties of the IR fingerprint of a rocket during its design phase without needing to spend excessive amounts of money on field trials. The modelled predictions of the IR spectra from selected rocket motor design parameters therefore bear significant benefits in reducing the development costs.The emission spectrum measured in the middle infrared (IR) band from the plume of a rocket can be used to identify rockets and track inbound missiles. It is useful to test the stealth properties of the IR fingerprint of a rocket during its design phase without needing to spend excessive amounts of money on field trials. The modelled predictions of the IR spectra from selected rocket motor design parameters therefore bear significant benefits in reducing the development costs. In a recent doctorate study it was f...