2/28/09

Near infrarednext term tomographic system based on high angular resolution mechanism – Design, calibration, and performance

This study aims at the design, implementation, and verification of a previous termnear infrarednext term (NIR) diffuse optical tomography (DOT) electro-optical imaging system based on a measuring instrument with single rotating source/detector scanning mechanism and an image reconstruction scheme implemented on an off-line PC. The developed measurement instrument possesses a high degree of angular resolution and is operated in a continuous-intensity scheme to acquire output NIR intensity signals. In this paper, some considerations of this measuring instrument are investigated such as phantom preparation, temporal stability, and container influence, etc. Experimental trials were conducted using both homogeneous and heterogeneous phantoms made of high-scattering microspheres or Intralipid.

In order to verify the developed imaging system with tomographic image reconstruction, the intensity was acquired from the heterogeneous Intralipid phantom using NIR light at 800 nm, where the homogenous background as the normal tissue is inserted with an inclusion as the tumor. For the comparison of heterogeneous phantoms with homogeneous phantoms, 1-D measured intensity signals indicate the angular position of the inclusion, especially for the case of the inclusion previous termnearnext term the phantom boundary. Furthermore, promising results of corresponding optical-property images can be reconstructed with the measured intensities as inputs of the image reconstruction scheme. Obviously, the developed NIR DOT tomographic system has been successfully built upon the experimental, analytical, and computational work.

2/27/09

Cooling effectiveness of effusion walls with deflection hole angles measured by infrarednext term imaging

Experimental investigations were performed on the overall cooling effectiveness of three effusion cooling test plates. The test plates had different hole-spacing (PS/d2 = 32.5 and 72), different deflection angle (β = 45° and 90°), and the same inclination angle (α = 30°). Although effusion cooling has been applied to advanced gas turbine combustors, its fundamental study seen in the open literature is limited. Using the previous terminfrarednext term (IR) imaging technique, the current study documented distribution of the overall cooling effectiveness on the surfaces of above specified flat walls. Based on the IR measured cooling effectiveness data, different effusion cooling configurations (different PS/d2 and β) were evaluated and the optimum configuration was determined. The current work demonstrated that the previous terminfrarednext term imaging technique served as an ideal method to detail cooling characteristics in the combustor heat transfer research.

2/26/09

Rapid and non-destructive analysis of apricot fruit quality using FT-near-infrarednext term spectroscopy

A non-destructive optical method based on previous termnear-infrarednext term spectroscopy has been used for the evaluation of apricot fruit quality. Diffuse reflectance measurements (800–2500 nm), physical, physiological and biochemical measurements were performed individually on 877 apricot fruits from eight contrasted cultivars harvested at different ripening stages. Relationships between spectral wavelengths and quality attributes were evaluated by application of chemometric techniques based on partial least squares (PLS) on fruit set divided randomly into two groups: 598 fruits for calibration and 279 for validation. Good prediction performance was obtained for soluble solids and titratable acidity with correlation coefficients of 0.92 and 0.89 respectively and root mean square errors of prediction of 0.98% Brix and 3.62 meq 100 g−1 FW respectively. For the other quality traits such as firmness, ethylene, individual sugars and organic acids, the prediction models were not satisfactorily accurate due to the high error of calibration and prediction.

2/25/09

Application of reflectance near infrarednext term spectroscopy for bread analyses

The feasibility of using previous termnear infrarednext term spectroscopy (NIRS) for prediction of nutrients in a wide range of bread varieties mainly produced from wheat and rye was investigated. Calibration was performed on samples collected over a 3-year-period and the calibration equations were tested on samples collected the subsequent year. Bread samples were dried, crushed, ground and measured in a rotating sample cup in the wavelength range 1100–2500 nm. Full range or segmented reflectance data was used for calibration based on partial least square (PLS) regression. Protein, fat, dietary fibre, sugar, ash, saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA) and Na could be determined directly with r2 values of 0.99, 0.99, 0.89, 0.96, 0.91, 0.90, 0.91, 0.92 and 0.76, respectively. The total contents of carbohydrates and energy was calculated from NIR data with r2 values of 0.98 and 0.99. The ratios between analyte variation range standard deviation (SD) and the root mean square error of cross validation (RMSECV) were 8.3 (protein), 9.1 (fat), 3.0 (dietary fibre), 4.7 (sugar), 3.0 (ash), 3.1 (SFA), 3.3 (MUFA), 3.5 (PUFA), 1.9 (Na), 7.2 (carbohydrates) and 8.4 (energy). Equivalent ratios were obtained on an independent test set. It is concluded that the applied NIRS methodology is suitable for routine analysis of wheat and rye based bread for the investigated organic properties and ash. The technique may also give a rough estimate of the Na content.

2/24/09

Potential used of near infrarednext term reflectance spectroscopy to predict meat physico-chemical composition of guinea fowl (Numida meleagris) reare

previous termNear infrarednext term reflectance spectroscopy (NIRS) was evaluated as a tool to predict the physico-chemical composition of samples of Guinea fowl (Numida meleagris) breast and thigh meat. Two different production systems were studied (confinement versus free-range) using 60 animals. The breast and thigh pieces were extracted from the carcass of each animal and analysed according to the official reference methods to determine the content in ash, fat, protein, WHC (water holding capacity), and DM (dry matter). All the samples were scanned to obtain their previous termnear infrarednext term reflectance spectrum, using a 19-filter device that reads in the wavelength range of 1445–2348 nm. Multiple linear correlation (MLR) was used as a statistical model to predict the physico-chemical composition. The best prediction equations were obtained for the fat and protein calibrations, with SEc = 0.310 and View the MathML source for fat, and SEc = 0.640 and View the MathML source for protein. The validation of the equations was also good for fat and protein (SEvc = 0.2179 and 1-variance ratio (VR) = 0.8342, SEvc = 1.9609 and 1-VR = 0.7609, respectively). The worst prediction equations were for the WHC and ash content, with SEc = 1.49, View the MathML source, SEvc = 4.1711, 1-VR = 0.392, and SEc = 0.030, View the MathML source, SEvc = 0.3421, 1-VR = 0.4631, respectively.

2/23/09

Simultaneous analysis of main catechins contents in green tea (Camellia sinensis (L.)) by Fourier transform near infrarednext term reflectance (FT-NIR

This paper reported the results of simultaneous analysis of main catechins (i.e., EGC, EC, EGCG and ECG) contents in green tea by the Fourier transform previous termnear infrarednext term reflectance (FT-NIR) spectroscopy and the multivariate calibration. Partial least squares (PLS) algorithm was conducted on the calibration of regression model. The number of PLS factors and the spectral preprocessing methods were optimised simultaneously by cross-validation in the model calibration. The performance of the final model was evaluated according to root mean square error of cross-validation (RMSECV), root mean square error of prediction (RMSEP) and correlation coefficient (R). The correlations coefficients (R) in the prediction set were achieved as follows: R = 0.9852 for EGC model, R = 0.9596 for EC model, R = 0.9760 for EGCG model and R = 0.9763 for ECG model. This work demonstrated that NIR spectroscopy with PLS algorithm could be used to analyse main catechins contents in green tea.

2/22/09

Use of near-infrarednext term reflectance spectroscopy for shelf-life discrimination of green asparagus stored in a cool room under controlled atmosph

This study sought to evaluate the ability of previous termnear-infrarednext term reflectance spectroscopy (NIRS) to classify intact green asparagus, in refrigerated storage under controlled atmosphere, by storage time and post-harvest treatments applied. A total of 468 green asparagus (Asparagus officinalis, L., cultivar UC-157) were sampled after 7, 14, 21 and 28 days of refrigerated storage (2 °C, 95% R.H.) under three controlled atmosphere (CA) treatments: air (21 kPa O2 + 0.3 kPa CO2), CA1 (5 kPa O2 + 5 kPa CO2) and CA2 (10 kPa O2 + 10 kPa CO2). Two commercially available spectrophotometers were evaluated for this purpose: a scanning monochromator (SM) of 400–2500 nm and a combination of diode array and scanning monochromator (DASM) of 350–2500 nm. Models developed using partial least squares 2-discriminant analysis (PLS2-DA) correctly classified between 81–100% of samples by post-harvest storage time, depending on the instrument used. Using similar models, the DASM instrument correctly classified 85% of samples by post-harvest treatment, compared with 72% using the SM. These results confirmed that NIR spectroscopy, coupled with the use of chemometric techniques, provides a reliable, accurate method of predicting the shelf-life of asparagus under different storage conditions and as a function of post-harvest treatment applied; the method can be readily applied at industrial level.

2/21/09

Testing of the Region of Murcia soils by near infrarednext term diffuse reflectance spectroscopy and chemometrics

A partial least squares previous termnear infrarednext term (PLS-NIR) method has been developed for the determination of several physicochemical parameters in soils from different locations of the Region of Murcia. The method was based on the proper chemometric treatment of diffuse reflectance spectra of soil samples. Reflectance spectra were scanned from samples stored in glass vials in the NIR region between 800 and 2600 nm, averaging 36 scans per spectrum at a resolution of 8 cm−1. Models were built using reference data of 39 samples selected from a dendrogram obtained after hierarchical cluster analysis of NIR spectra of soils and prediction parameters were established from a validation set of 109 additional samples of the same area not considered to build the model. Organic matter, CaCO3, pH, electrical conductivity (EC), together with several trace metals as Cr, Co, Ni, Cu, Zn, As, Se, Cd and Tl, were employed as characteristic parameters of the soils under study, and found results evidenced that PLS-NIR provides a valuable tool for screening purposes providing residual predictive deviations which ranged from 0.9 to 1.5 as a function of the considered parameter.

2/20/09

The spatial effect of near-infrarednext term spectroscopy and its application to the study of supramolecular chemistry

An unlooked-for experimental observation that in previous termnear-infrarednext term spectroscopy (NIR) the absorption peak of the second overtone of aniline adsorbed by 13X molecular sieve nearly disappeared led us investigate a fundamental question: the behavior of NIR when the outside space surrounding a molecule is too small to allow the molecule to vibrate freely. Through NIR of various organic compounds adsorbed by different porous inorganic materials like 13X molecular sieve, silica gel and active aluminium oxide, and NIR of supramolecular cyanuric acid-melamine, we can reasonably confirm a theoretical inference that in the micro-environment above, all intensities of NIR absorbance decrease, and the second overtone decreases more than the first overtone does. Furthermore, one distinct feature of NIR, higher sensitivity to the size of micro-environmental space as compared with mid-previous terminfrarednext term (MIR), and its potential application to the study of supramolecular structure are outlined by our experiments.

2/19/09

Noninvasive in situ identification and band assignments of some pharmaceutical excipients inside USP vials with FT-near-infrarednext term spectroscopy

For the manufacture of dosage forms all ingredients must be reliably identified. In this paper, the suitability of FT-NIR spectroscopy to identify potassium sorbate, sodium starch glycollate, calcium ascorbate, calcium carbonate, candelilla wax, maltosextrin, monohydrated and anhydrous lactose inside USP vials was investigated. Differentiation between the anhydrous and monohydrated forms of lactose was found to be possible by studying the regions of the previous termnear-infrarednext term spectrum corresponding to the combination and first overtone stretching frequencies of water. The results show unequivocally the potential of FT-NIR spectroscopy for rapid, in situ and non-destructive identification of pharmaceutical excipients.

2/18/09

Near infrarednext term spectral fingerprinting for confirmation of claimed PDO provenance of honey

previous termNear infrarednext term spectroscopic fingerprints of Corsican honey samples were analysed by a range of chemometric tools to confirm their claimed provenance. Authentic, unfiltered honeys (n = 373; 219 Corsican and 154 non-Corsican) were collected over 2 production seasons, the goal being to create a specific spectral fingerprint for Corsican honey. Following preliminary data examination by principal component analysis, the multivariate method studied for provenance confirmation was partial least squares regression; various spectral pre-treatments were investigated. Best PLS discriminant models developed using full cross-validation, a variable selection algorithm and a 2nd derivative data pre-treatment, gave correct classification results of 90.0% and 90.3% for the Corsican and non-Corsican honey samples respectively. Using separate calibration and validation samples from this same honey collection, highest correct classification values of 90.4% and 86.3% for Corsican and non-Corsican honey samples respectively were obtained again using a variable selection procedure.

2/17/09

ulsed infrarednext term radiation transmission through hollow silica waveguides

Transmission measurements of Q-switched and free-running Er:YAG laser radiation, at 2.94 μm and free-running Ho:YAG laser radiation, at 2.06 μm, through hollow silica waveguides of 750 and 1000 μm core diameter were performed. Attenuation measurements were obtained as a function of the laser energy input and as a function of the bending curvature. The output beam quality was also studied as a function of the focal length of the coupling lens and the overall launching conditions for straight waveguides using the appropriate beam profiler.

2/16/09

Comparison and modeling of microwave tempering and infrarednext term assisted microwave tempering of frozen potato puree

Microwave tempering and previous terminfrarednext term assisted microwave tempering of frozen foods were simulated by using finite difference method. The effects of microwave power and previous terminfrarednext term power on tempering were discussed. Three different microwave power levels (30%, 40%, and 50%) and three different previous terminfrarednext term power levels (10%, 20%, and 30%) were used. The increase in microwave power level and previous terminfrarednext term power level decreased tempering times. The change of heat capacity and the dielectric properties of frozen potato puree with respect to time were measured. The temperature distribution inside the sample was modeled, and the predicted results were compared with experimental results. The predicted temperatures showed good agreement with the experimental results.

2/15/09

The application of near infrarednext term spectroscopy technology and a remote reflectance fibre-optic probe for the determination of peptides in chee

The use of previous termnear infrarednext term spectroscopy (NIRS) technology employing a remote reflectance fibre-optic probe (with a 5 cm × 5 cm quartz window) for the analysis of the hydrophilic (HI) and hydrophobic (HO) peptides and the ratio HO/HI was assayed. To do so, cheeses with known and varying percentages of cow’s, ewe’s and goat’s milk were elaborated (112 samples). Ripening controls were performed over 6 months, and the chemical data obtained by reversed-phase high performance liquid chromatography used as reference. The regression method employed was modified partial least squares (MPLS). The multiple correlation coefficients (RSQ) and prediction corrected standard errors (SEP (C)) obtained 0.879 and 1.83% for hydrophilic (HI) and 0.879 and 1.83% for hydrophobic (HO) peptides, respectively, and 0.890 and 0.03% for the ratio HO/HI. The method allows immediate control by direct application of the fibre-optic probe to the cheese without prior sample treatment or destruction.

2/14/09

Monitoring of fatty acid composition in virgin olive oil by Fourier transformed infrarednext term spectroscopy coupled with partial least squares

A rapid Fourier transformed previous terminfrarednext term (FTIR) attenuated total reflectance (ATR) spectroscopic method was applied to the determination of fatty acid (FA) profile and peroxide value (PV) of virgin olive oil. Calibration models were constructed using partial least squares (PLS) regression. A FA calibration model was constructed in the spectral range from 3033 to 700 cm−1. Oleic acid (62.0–80.0%), linoleic acid (5.3–15.0%), saturated fatty acids (SFA, 12.6–19.7%), mono-unsaturated fatty acids (MUFA, 64.4–81.0%) and poly-unsaturated fatty acids (PUFA, 6.0–15.9%) were considered for chemometric analysis. PV (5.7–15.7 meq O2 kg−1) was calibrated using the signal of the full spectral range 4000–700 cm−1 with first derivative pre-treatment. The LODs of the FTIR-chemometric methods were: 3.0% for oleic acid, 0.5% for linoleic acid, 1.3% for SFA, 3.0% for MUFA, 0.3% for PUFA and 1.0 meq O2 kg−1 for PV. Analytical methods were evaluated by use of validation samples (n = 25 for all the FA related parameters and n = 10 for PV) with nearly quantitative recovery rates (98–103%). The proposed method provided results comparable to official procedures, with the advantages of being less expensive and more rapid.

2/13/09

NIR analysis of cellulose and lactose—Application to ecstasy tablet analysis

Cellulose and lactose are the most frequently used excipients in illicit ecstasy production. The aim of this project was to use near infrared reflectance spectroscopy (NIRS) for the determination of the different chemical forms of these two substances, as well as for the differentiation of their origin (producer). It was possible to distinguish between the different chemical forms of both compounds, as well as between their origins (producers), although within limits. Furthermore, the possibilities to apply NIR for the analysis of substances such as found in illicit tablets were studied. First, a few cellulose and lactose samples were chosen to make mixtures with amphetamine at three degrees of purity (5, 10 and 15%), in order to study the resulting changes in the spectra as well as to simultaneously quantify amphetamine and identify the excipient. A PLS2 model could be build to predict concentrations and excipient. Secondarily, the technique was to be applied to real ecstasy tablets. About 40 ecstasy seizures were analysed with the aim to determine the excipient and to check them against each other. Identification of the excipients was not always obvious, especially when more than one excipient were present. However, a comparison between tablets appeared to give groups of similar samples. NIR analysis results in spectra representing the tablet blend as a whole taking into account all absorbing compounds. Although NIRS seems to be an appropriate method for ecstasy profiling, little is known about intra- and intervariability of compression batches.

2/12/09

Extending Near Infrared Reflectance(NIR) Pulp Yield Calibrations to NewSites and Species

Recently, we demonstrated that the accuracy of pulp yield predictions for wood samples from a site (Gog) new to their calibration (Tasmania-wide Eucalyptus nitens) was greatly improved by adding five Gog samples to the calibration set. In this study we investigated the addition of Gog samples to the Tasmania-wide E. nitens set, with the aim of further improving predictive accuracy. It was demonstrated that the addition of a single Gog sample to the Tasmania-wide calibration set was sufficient to greatly reduce predictive errors and that the inclusion of at least 3 Gog samples in the Tasmania-wide set was sufficient to give relatively stable predictive errors. The addition of different sets of 5 Gog samples to the Tasmania-wide calibration, however, caused predictive errors to vary between sets. The standard deviation of pulp yield for the prediction set (20 Gog samples) was important, with sets having the largest standard deviations giving the best predictive statistics. Finally, the Tasmania-wide E. nitens calibration was enhanced using samples from a different species (Eucalyptus globulus) and applied successfully to other E. globulus samples.

2/11/09

Comparing the limiting resolution of the Cary 5000 and Cary 6000i UV-Vis-NIR spectrophotometers using the transmission spectrum of water vapor

Introduction

The NIR spectra of many gases and solids exhibit narrow bands containing vibrational fine structure. Resolving these peaks, which are on the order of <>

Theory

The resolving power of an absorption spectrophotometer depends on a number of different mechanical instrument parameters. These include the grating resolution (lines per mm), focal length of the monochromator, the minimum slit width and the minimum stepping interval. These parameters, along with the detector sensitivity across the wavelength range of interest, dictate the minimum resolution. A common, but incorrect, assumption often made is that the minimum resolution is only dependent on the spectral band width. If there are not enough data points collected, or the signal-to-noise (S/N) is extremely low, then the fine spectral characteristics of the sample will not be resolved.

To resolve a peak, it is a general requirement to set the SBW to 1/3rd the natural peak width, and the data interval to 1/10th the natural peak width. However, the narrower the SBW setting, the lower the amount of light hitting the detector, hence, the sensitivity of the detector becomes a very important factor if good S/N spectra are to be collected. Varian’s high performance spectrophotometers can measure the most demanding samples and the release of the new generation Cary 5000 and Cary 6000i UV-Vis-NIR absorption spectrophotometers has raised the bar to a new level. In theory, the Cary 6000i can resolve a peak of between 0.06 – 0.1 nm natural bandwidth in a relatively short time. Without a doubt, the new generation Cary range are the best UV-Vis-NIR instruments available on the market today.

Discussion

The difference between the Cary 5000 and 6000i is the minimum resolution and sensitivity. As mentioned earlier, the narrower the SBW setting, the less light hits the detector, which results in poorer S/N or requires a much longer averaging time. The Cary 6000i has a minimum SBW of 0.02 nm and uses an InGaAs detector, which has approximately 100 times greater sensitivity than the traditional PbS detectors used in most NIR measurements. This is evident in Figure 2, where signal averaging of only two seconds was required to achieve excellent S/N compared to the Cary 5000 instrument using ten seconds signal averaging time, as shown in Figure 1. Also, the SBW setting on the Cary 5000 was 0.05 nm compared to 0.02 nm on the Cary 6000i. This difference in resolution results in the peak at 1380 nm being better resolved into a doublet on the 6000i compared to the 5000, as shown in Figure 3. For comparison, this 1380 nm peak cannot be resolved into a doublet on other UV-Vis-NIR absorption spectrophotometers.

Conclusion

The Cary 5000 and 6000i instruments are by far the best spectrophotometers on the market today if high sensitivity and fine spectral resolution are required. Both instruments can resolve a peak of <0.5 nm bandwidth, with the additional sensitivity of the Cary 6000i InGaAs detector providing an order of magnitude increase in speed and throughput. Both instruments have provided new technology that will benefit customers in all areas of research.

2/10/09

Solutions Manual for Organic Chemistry and the CW+ GradeTracker Access Card Package (Workbook only, no Access Card included)



life saver5
I would have probably failed o-chem without this book. Although it does not explain how they got the answers, it is really helpful for copying for homework credit. and it occasionally helped me learn something

Absolutely necessary for Org Chem5
If your text book is Organic Chemisty by Wade, this solutions manual is a MUST-HAVE. The book has many problems, and only some have the answers in the back so that you may check your answers. But there is very very few questions in the book that show you how to solve it. The solutions manual shows you step-by-step ways to solve the problems and gives you tips and reasons why the answer is the way it is. I cant imagine having taken Organic without the solutions manual. Taking this course with our this manual is just making this class 5x harder for no need! I highly recommend this book!

Detailed solutions manual5
This manual is a key to success in organic chemistry. The more practice problems you do and do correctly the better you will do in the course. If you are using the Wade textbook I highly recomend spending a little more money and geting the solutions manual. This manual covers not just the odd numbeered problems, but covers every problem in the entire text. If there is a problem in the text you want the answer for it is in this solutions manual. The other nice thing is the manual gives you a couple of different solutions for a problem that has multiple answers.

About Solutions Manual for Organic Chemistry and the CW+ GradeTracker Access Card Package (Workbook only, no Access Card included) detail

  • Amazon Sales Rank: #2242 in Books
  • Published on: 2005-04-23
  • Original language: English
  • Number of items: 1
  • Binding: Paperback
  • 720 pages

Solutions Manual for Organic Chemistry and the CW+ GradeTracker Access Card Package (Workbook only, no Access Card included) Description

The Solutions Manual, prepared by Jan W. Simek of California Polytechnic State University, contains complete solutions to all the problems. The Solutions Manual also gives helpful hints on how to approach each kind of problem. This supplement is a useful aid for any student, and it is particularly valuable for students who feel they understand the material but need more help with problem solving. Appendix 1 of the Solutions Manual summarizes the IUPAC system of nomenclature. Appendix 2 reviews and demonstrates how acidity varies with structure in organic molecules, and how one can predict the direction of an acid--base equilibrium. Brief answers to many of the in-chapter problems are given at the back of this book. These answers are sufficient for a student on the right track, but they are of limited use to one who is having difficulty working the problems.


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