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methods cannot be used for rapid comprehensive quality inspection of Phalaenopsis plants. Near-infrared (NIR) spectroscopy, a rapid inspection method based on specific absorptions within a given range of wavelengths corresponding to the constituents of

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soluble solids concentration (SSC) and acidity content in grapefruit by the time-of-flight near-infrared spectroscopy (TOF-NIRS) versus near-infrared spectroscopy (NIRS). We should also consider that absorption resulting from OH groups appears from 750 to

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methodology and, in the case of the sugars, expensive and labor-intensive equipment. Near-infrared (NIR) spectroscopy, which is a nondestructive method for fruit quality evaluation, has become a very popular technique and has been used to evaluate the internal

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.1109/TGRS.2016.2584107 10.1109/TGRS.2016.2584107 Cortés, V. Cubero, S. Aleixos, N. Blasco, J. Talens, P. 2017 Sweet and nonsweet taste discrimination of nectarines using visible and near-infrared spectroscopy Postharvest Biol. Technol. 133

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Mart.) as affected by clarification, ascorbic acid fortification and storage Food Res. Intl. 40 620 628 Pasquini, C. 2003 Near infrared spectroscopy: Fundamentals, practical aspects and analytical applications J. Brazilian Chemist. Soc. 14 198 219 Peirs

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vegetable quality by means of NIR spectroscopy: A review Postharvest Biol. Technol. 46 2 99 118 Osborne, S.D. Jordan, R.B. Künnemeyer, R. 1996 Using near-infrared (NIR) light to estimate the soluble solids and dry matter content of kiwifruit Acta Hort. 464

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The ability to predict thatch composition with the use of near-infrared reflectance spectroscopy (NIRS) was investigated. This study compared a new quick test for evaluating different thatch components using NIRS with the Van Soest wet chemical analysis. Creeping bentgrass (Agrostis palustris Huds.) thatch samples were taken from an experimental golf green at the Valentine Turfgrass Research Center at Penn State Univ. Fresh and dried ground samples were scanned from 400 to 2500 nm with a near-infrared monochromator. Dried ground samples were analyzed in four replicates using the Van Soest procedures for the acid detergent fiber, cellulose, and lignin. Moisture and organic matter contents were also evaluated in the laboratory. Preliminary comparisons between predicted NIRS values and laboratory results were encouraging. NIRS analysis of thatch could become a convenient, rapid, and inexpensive alternative to wet chemical analysis for thatch assessment.

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The ability to predict moisture and organic matter contents as well as soil particle size distribution of a golf course turf media with the use of near infrared reflectance spectroscopy (NIRS) was investigated. This study compared a new quick test, NIRS, with the use of wet chemical analysis for the evaluation of different soil characteristics. Samples were taken from greens and fairways of central Pennsylvania golf courses and from two turfgrass research centers at The Pennsylvania State Univ. Fresh samples were vertically scanned by 1.27-cm increments, from 400 to 2500 nm, with a near infrared monochromator. Moisture and organic matter contents were evaluated in the laboratory. The pipette method was used to determine the particle size distribution. Correlations of 84% and higher were obtained for the sand, silt, and clay values as well as for the moisture and organic matter contents. NIRS analysis of soil characteristics could become a convenient, rapid, and inexpensive alternative to wet chemical analysis for golf course management.

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Time-of-flight near-infrared spectroscopy (TOF-NIRS) was used to investigate optical characteristics of water-cored tissue in `Fuji' apples [Malus sylvestris (L.) Mill. var. domestica (Borkh. Mansf.)]. The combined effects on the time resolved profiles of water core, laser beam wavelength, and detection position of transmitted light were investigated in detail. Attenuance of peak maxima (At ), time delay of peak maxima (Δt), and variation of full width at half maximum (Δw) decreased gradually as water core increased. Water-cored tissue transmitted much more energy because of the filling of intercellular spaces with liquid, so that the light path time through a sample decreased. These parameters were also strongly dependent on detection position and wavelength of the laser beam. The substantial optical path length calculated from Δt at λ = 800 nm was 10 to 17 times, while that for λ = 900 nm varied from six to 11 times the distance of the diameter of the fruit. Results indicated the optimum optical parameter for detection of water core was Δt.

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Application of nutrients to correct nutrient deficiencies in turfgrasses are often based on tissue analysis. Previous research has indicated that near infrared reflectance spectroscopy (NIRS) may be useful in tissue nutrient concentration determination since it requires minimum sample preparation and has been a reliable predictor of N concentration. The objective of this study was to evaluate the reliability of NIRS in determining P, K, Ca, and Mg concentrations in bermudagrass [Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt Davy]. Tissue samples were collected from Florida golf courses, representing different cultivars grown under various conditions and fertilizer regimes. Tissue samples were analyzed using NIRS and traditional wet chemistry (Mehlich-1 extracts analyzed using inductively coupled argon spectrophotometer) before results were statistically compared. Results from wet chemistry analysis averaged 15% lower than those obtained from NIRS. Although results for certain cultivars and elements were positively correlated (`Tifdwarf' Ca, r 2 = 0.72; P < 0.01), precision across all cultivars and nutrients was not sufficient (accounted for only 26% of variability) to indicate that NIRS would be an effective management tool for the elements evaluated in this study.

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