Use of Heat to Saponify Xanthophyll Esters and Speed Analysis for Carotenoids in Feed Materials: Collaborative Study

1973 ◽  
Vol 56 (3) ◽  
pp. 748-753
Author(s):  
Forrest W Quackenbush
Keyword(s):  
Room Temperature ◽  
Collaborative Study ◽  
Extraction Technique ◽  
Good Precision ◽  
Corn Gluten ◽  
Speed Up ◽  
Alfalfa Meal ◽  
Xanthophyll Esters ◽  
Good Agreement

Abstract Twelve collaborators analyzed 4 pairs of samples to compare a 20 min hot (56°C) saponification technique with the overnight extraction technique at room temperature in the official first action method for analysis of carotenoids in feed materials, 39.018–39.023, with a view to (a) make the method applicable to products which contain xanthophyll esters and (b) speed up the analysis. In general, the collaborators were in good agreement, with saponification of esters essentially complete after the 20 min heating of samples that contained marigold meal. While the sum of extracted pigments from corn gluten and alfalfa meal tended to be slightly higher with the longer (overnight) contact with the solvent than with the hot extraction, the differences were not statistically significant. Significant differences between hot and cold treatments were absent also in alfalfa pigment fractions, but hot saponification significantly lowered monohydroxy pigments and increased dihydroxy pigments in extracts from corn gluten. The results showed good precision with either extraction technique. The method, modified to include hot saponification as an alternative step, is now applicable to all dried feed materials, including those which contain xanthophyll esters (e.g., marigold meal); the modification has been incorporated into the official first action method, 39.018–39.023.

Xanthophylls and Carotenes in Feeds and Feed Materials: Collaborative Study

1970 ◽  
Vol 53 (1) ◽  
pp. 186-189 ◽  
Author(s):  
F W Quackenbush
Keyword(s):  
Satisfactory Agreement ◽  
Collaborative Study ◽  
Mixed Feed ◽  
Corn Gluten ◽  
Alfalfa Meal

Abstract Eight laboratories showed satisfactory agreement in analysis of three pairs of samples (corn gluten, alfalfa meal, and mixed feed) by a proposed method for xanthophylls and carotenes. The method permits separation of monohydroxy pigments from dihydroxy pigments and excludes the non-pigmenting (avian) polyoxy pigments. It is recommended for adoption as official first action.

Dislocation structures around SiO2 Particles in aged Cu-Cr-SiO2

1978 ◽  
Vol 36 (1) ◽  
pp. 594-595
Author(s):  
N.J. Long ◽  
M.H. Loretto ◽  
C.H. Lloyd
Keyword(s):  
Flow Stress ◽  
Single Crystals ◽  
Room Temperature ◽  
Thin Foil ◽  
Age Hardening ◽  
Dispersion Strengthening ◽  
Accurate Picture ◽  
The Matrix ◽  
Very High ◽  
Good Agreement

IntroductionThere have been several t.e.m. studies (1,2,3,4) of the dislocation arrangements in the matrix and around the particles in dispersion strengthened single crystals deformed in single slip. Good agreement has been obtained in general between the observed structures and the various theories for the flow stress and work hardening of this class of alloy. There has been though some difficulty in obtaining an accurate picture of these arrangements in the case when the obstacles are large (of the order of several 1000's Å). This is due to both the physical loss of dislocations from the thin foil in its preparation and to rearrangement of the structure on unloading and standing at room temperature under the influence of the very high localised stresses in the vicinity of the particles (2,3).This contribution presents part of a study of the Cu-Cr-SiO2 system where age hardening from the Cu-Cr and dispersion strengthening from Cu-Sio2 is combined.

Collaborative Study of a Titrimetric Method for the Assay of Amitrole Formulations

1967 ◽  
Vol 50 (3) ◽  
pp. 568-572
Author(s):  
J Russell Bishop
Keyword(s):  
Collaborative Study ◽  
Statistical Analyses ◽  
Standard Samples ◽  
Titrimetric Method ◽  
Inflection Points ◽  
Good Agreement

Abstract titrimetric method for the assay of dry and liquid amitrole formulations was studied by 10 collaborators. In the method, acid is added to the prepared amitrole sample, the solution is titrated potentiometrically with standard alkali, and the amitrole content is measured as the amount of alkali consumed between the first and second inflection points. Collaborative results on standard samples of a dry 90% formulation, a dry 50% formulation, and a liquid 2 lb/gallon formulation showed good agreement between samples and laboratories. Statistical analyses of the results were satisfactory, and the method for the assay of amitrole formulations is recommended for adoption as official, first action

Defect Structure of MEV Si Implantation in GaAs

1988 ◽  
Vol 126 ◽  
Author(s):  
S.-Tong Lee ◽  
G. Braunstein ◽  
Samuel Chen
Keyword(s):  
Free Surface ◽  
Defect Structure ◽  
Room Temperature ◽  
Surface Region ◽  
Peak Position ◽  
Lattice Disorder ◽  
Depth Profiles ◽  
Trim Calculation ◽  
Good Agreement

ABSTRACTThe defect and atomic profiles for MeV implantation of Si in GaAs were investigated using He++ channeling, TEM, and SIMS. Doses of 1–10 × 1015Si/cm2 at 1–3 MeV were used. MeV implantation at room temperature rendered only a small amount of lattice disorder in GaAs. Upon annealing at 400°C for 1 h or 800°C for 30 a, we observed a ‘defect-free’ surface region (- 1 μ for 3 MeV implant). Below this region, extensive secondary defects were formed in a band which was 0.7 μ wide and centered at 2 μ for 3 MeV implant. These defects were mostly dislocations lying in the [111] plane. SIMS depth profiles of Si implants showed the Si peak to be very close to the peak position of the defects. The experimental profiles of Si were compared to the TRIM calculation; generally good agreement existed among the peak positions.

Analysis of Thermal Variation of Length and Refractive Index of Lead Fluoride to Study its Optical Properties

1989 ◽  
Vol 172 ◽  
Author(s):  
T. S. Aurora ◽  
D. O. Pederson ◽  
S. M. Day
Keyword(s):  
Refractive Index ◽  
Room Temperature ◽  
Linear Thermal Expansion ◽  
Small Variation ◽  
Published Data ◽  
Thermal Variation ◽  
Lead Fluoride ◽  
Superionic Phase Transition ◽  
Lorenz Relation ◽  
Good Agreement

AbstractLinear thermal expansion and refractive index variation have been measured in lead fluoride with a laser interferometer as a function of temperature. Data has been analyzed using the Lorentz-Lorenz relation. Molecular polarizability, band gap, variation of refractive index with density, and strain-polarizability parameter have been studied as a function of temperature. They exhibit a small variation with temperature except near the superionic phase transition where the variation appears to be more pronounced. The results are in good agreement with the published data near room temperature.

scholarly journals Laser ablation ICP-MS of size-segregated atmospheric particles collected with a MOUDI cascade impactor: a proof of concept

2017 ◽  
Vol 10 (5) ◽  
pp. 1823-1830 ◽  
Author(s):  
Marin S. Robinson ◽  
Irena Grgić ◽  
Vid S. Šelih ◽  
Martin Šala ◽  
Marsha Bitsui ◽  
...  
Keyword(s):  
Laser Ablation ◽  
Submicron Particles ◽  
Good Precision ◽  
The Novel ◽  
Proof Of Concept ◽  
Image Mapping ◽  
Icp Ms ◽  
Elemental Image ◽  
Elemental Maps ◽  
Good Agreement

Abstract. A widely used instrument for collecting size-segregated particles is the micro-orifice uniform deposit impactor (MOUDI). In this work, a 10-stage MOUDI (cut-point diameter of 10 µm to 56 nm) was used to collect samples in Ljubljana, Slovenia, and Martinska, Croatia. Filters, collected with and without rotation, were cut in half and analyzed for nine elements (As, Cu, Fe, Ni, Mn, Pb, Sb, V, Zn) using laser ablation ICP-MS. Elemental image maps (created with ImageJ) were converted to concentrations using NIST SRM 2783. Statistical analysis of the elemental maps indicated that for submicron particles (stages 6–10), ablating 10 % of the filter (0.5 cm2, 20 min ablation time) was sufficient to give values in good agreement (±10 %) to analysis of larger parts of the filter and with good precision (RSE < 1 %). Excellent sensitivity was also observed (e.g., 20 ± 0.2 pg m−3 V). The novel use of LA-ICP-MS, together with image mapping, provided a fast and sensitive method for elemental analysis of size-segregated MOUDI filters, particularly for submicron particles.

Experimental Verification of Constitutive Equations for Creep and Plasticity Based on Overlay Models

1983 ◽  
Vol 105 (3) ◽  
pp. 277-284 ◽  
Author(s):  
P. Meijers ◽  
F. Roode
Keyword(s):  
Plastic Deformation ◽  
Room Temperature ◽  
304 Stainless Steel ◽  
Model Parameters ◽  
General Description ◽  
Time Effects ◽  
Plastic Deformations ◽  
Biaxial Load ◽  
Theoretical Predictions ◽  
Good Agreement

A general description of creep and plastic deformation based on overlay models is presented. This includes the description of time effects during plastic deformation at room temperature. A detailed procedure to obtain the model parameters is also discussed. The description has been evaluated for a large number of uniaxial and biaxial load histories on thin walled tubes. The materials involved are a 2 1/4 Cr-1 Mo steel stabilized with Niobium (WN 1.6770) and a 304 stainless steel (WN 1.4948). The theoretical predictions of the plastic deformations are found to be sufficiently accurate. The evaluation of the phenomenological description for creep shows a fairly good agreement with the real creep deformation process. Special attention requires the description of softening due to microstructural changes.

scholarly journals Organic acids as cloud condensation nuclei: Laboratory studies of highly soluble and insoluble species

2003 ◽  
Vol 3 (1) ◽  
pp. 949-982 ◽  
Author(s):  
P. Pradeep Kumar ◽  
K. Broekhuizen ◽  
J. P. D. Abbatt
Keyword(s):  
Organic Acids ◽  
Room Temperature ◽  
Cloud Condensation Nuclei ◽  
Particle Diameter ◽  
Diffusion Chamber ◽  
Laboratory Studies ◽  
Condensation Nuclei ◽  
Gradient Diffusion ◽  
Kohler Theory ◽  
Good Agreement

Abstract. The ability of sub-micron-sized organic acid particles to act as cloud condensation nuclei (CCN) has been examined at room temperature using a newly constructed continuous-flow, thermal-gradient diffusion chamber (TGDC). The organic acids studied were: oxalic, malonic, glutaric, oleic and stearic. The CCN properties of the highly soluble acids – oxalic, malonic and glutaric – match very closely Kohler theory predictions which assume full dissolution of the dry particle and a surface tension of the growing droplet equal to that of water. In particular, for supersaturations between 0.3 and 0.6, agreement between the dry particle diameter which gives 50% activation and that calculated from Kohler theory is to within 3 nm on average. In the course of the experiments, considerable instability of glutaric acid particles was observed as a function of time and there is evidence that they fragment to some degree to smaller particles. Stearic acid and oleic acid, which are both highly insoluble in water, did not activate at supersaturations of 0.6% with dry diameters up to 140 nm. Finally, to validate the performance of the TGDC, we present results for the activation of ammonium sulfate particles that demonstrate good agreement with Kohler theory if solution non-ideality is considered. Our findings support earlier studies in the literature that showed highly soluble organics to be CCN active but insoluble species to be largely inactive.

scholarly journals Study of Spectroscopy and Thermodynamic Properties for Phoshours dioxide PO2 Molecular and Influence Study of Bond ( P-O ) on Spectroscopy Properties

2012 ◽  
Vol 9 (4) ◽  
pp. 616-622
Author(s):  
Baghdad Science Journal
Keyword(s):  
Free Energy ◽  
Thermodynamic Properties ◽  
Room Temperature ◽  
Formation Enthalpy ◽  
Heat Of Formation ◽  
Vibration Modes ◽  
Equilibrium Distance ◽  
Atmosphere Pressure ◽  
Gibb’S Free Energy ◽  
Good Agreement

In This research a Spectroscopic complement and Thermodynamic properties for molecule PO2 were studied . That included a calculation of potential energy . From the curve of total energy for molecule at equilibrium distance , for bond (P-O), the degenerated of bond energy was (4.332eV) instate of the vibration modes of ( PO2 ) molecule and frequency that was found active in IR spectra because variable inpolarization and dipole moment for molecule. Also we calculate some thermodynamic parameters of ( PO2 ) such as heat of formation , enthalpy , heat Of capacity , entropy and gibb's free energy Were ( -54.16 kcal/mol , 2366.45 kcal/mol , 10.06 kcal /k/mol , 59.52 kcal /k /mol, -15370.51 kcal / mol ) respectively under condition of room temperature and atmosphere pressure ( 298 k , 1 atm.). We calculate there parameters at various temperature from ( 100 – 3000 ) K . It was found that the obtainded results were in a good agreement with previous experimental facts.

Analytical approach for transient photoconductivity in undoped a-Si:H

1995 ◽  
Vol 377 ◽  
Author(s):  
M. Goerlitzer ◽  
P. Pipoz ◽  
H. Beck ◽  
N. Wyrsch ◽  
A. V. Shah
Keyword(s):  
Steady State ◽  
Theoretical Model ◽  
Analytical Approach ◽  
Room Temperature ◽  
Free Electrons ◽  
Recombination Time ◽  
Sample Quality ◽  
Transient Photoconductivity ◽  
Light Intensities ◽  
Good Agreement

ABSTRACTTransient photoconductive response of undoped a-Si:H has been studied; the changes were analysed between two slightly different steady-state illumination conditions, at room temperature. A theoretical model is developed to describe transient photoconductivity; it yields good agreement with the measured curves for a whole range of light intensities. Numerical evaluations allows one to extract the recombination time of electrons. Comparison with steady-state photoconductivity yields a band mobility of free electrons between 0.1 and 6 cm2V−1s−1, depending upon sample quality.

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