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61.
A study was carried out to determine quantitatively the number and location of spectral bands required to perform general rock type discrimination from spaceborne imaging sensors using only thermal infrared measurements. Beginning with laboratory spectra collected under idealized conditions from relatively well-characterized homogeneous samples, a radiative transfer model was used to transform ground exitance values into the corresponding spectral radiance at the top of the atmosphere. Taking sensor noise into account, analysis of these data revealed that three 1 μ wide spectral bands would permit independent estimations of rock type and sample temperature from a satellite infrared multispectral scanner. This study, which ignores the mixing of terrain elements within the instantaneous field of view of a satellite scanner, indicates that the location of three spectral bands at 8.1–9.1, 9.5–10.5, and 11.0–12.0 μ, and the employment of appropriate preprocessing to minimize atmospheric effects makes it possible to predict general rock type and temperature for a variety of atmospheric states and temperatures.  相似文献   
62.
We consider the relationships between binary search algorithms and binary prefix encodings of infinite linearly ordered sets. It is known that each search algorithm determines a prefix code, and in three cases we show to what extent the converse is true. For sets similar to the natural numbers we show that search-related codes are as flexible as all prefix codes, while for general ordered sets they are only asymptotically as flexible.Research partially supported by a fellowship from the State University of New York University Awards Committee.  相似文献   
63.
Dulay MT  Baca QJ  Zare RN 《Analytical chemistry》2005,77(14):4604-4610
Trypsin is covalently linked to a photopolymerized sol-gel monolith modified by incorporating poly(ethylene glycol) (PSG-PEG) for on-column digestion of N(alpha)-benzoyl-l-arginine ethyl ester (BAEE) and two peptides, neurotensin and insulin chain B. The coupling of the enzyme to the monolith is via room-temperature Schiff chemistry in which an alkoxysilane reagent (linker) with an aldehyde functional group links to an inactive amine on trypsin to form an imine bond. The proteolytic activity of the immobilized trypsin was measured by monitoring the formation of N alpha-benzoyl-L-arginine (BA), the digestion product of BAEE. The BA is separated from BAEE by capillary electrophoresis and detected downstream (18.5 cm from the microreactor) by absorption (254 nm). Using the Bradford assay, we determined that 97 ng of trypsin is bound to the 1-cm microreactor located at the entrance of capillary column. The bioactivity of the trypsin-PSG-PEG microreactor at 20 degrees C for the digestion of BAEE was found to be 2270 units/mg of immobilized trypsin. The bioactivity of trypsin bound to the capillary wall in the open segment upstream from the monolith was 332 units/mg of immobilized trypsin under the same conditions. In contrast, the activity of free trypsin could not be observed for the digestion of BAEE at 20 degrees C after 16 h of incubation time.  相似文献   
64.
Seed oils from 37 plant species in 18 families have been analyzed for fatty acid composition by the isomerization method. The variability encountered is evidenced by the range in content of component acids: from 0–23% for apparent linolenic acid, from 8–74% for apparent linoleic acid, and from 2–88% for apparent oleic acid. Dimorphecolic acid has been found to the extent of approximately 60% in a second species ofDimorphotheca, D. pluvialis (L.) Moench, and in the closely related species,Osteospermum ecklonis (DC.) T. Norl.O. spinescens Thunb. contained instead 30% of a conjugated triene, presumably the same as the 8,10,12-octadecatrienoic reported from the relatedCalendula officinalis L. Oils rich in monoenoic acids are mostly in the Umbelliferae and Araliaceae and presumably contain petroselinic acid as well as oleic. Presented at the AOCS meeting in St. Louis, Mo., May 1–3, 1961. A laboratory of the Northern Utilization Research and Development Division, Agricultural Research Service, U.S.D.A. Agricultural Research Service, U.S.D.A.  相似文献   
65.
Ohne ZusammenfassungEinschließlich Besprechungen vonDiplomarbeiten undDissertationen.  相似文献   
66.
67.
Summary Chemical screening of seed oils continues to reveal nature's diversity. This work provides leads to numerous species which warrant further research to investigate their oil and meal in greater detail, to appraise their crop potential, and to assess their practical value for providing new oilseeds. This is a laboratory of the Northern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture. Agricultural Research Service, U. S. Department of Agriculture.  相似文献   
68.
69.
Using thick and thin films instead of bulk functional materials presents tremendous advantages in the field of flexible electronics and component miniaturization. Here, a low-cost method to grow and release large-area, microscale thickness, freestanding, functional, ceramic foils is reported. It uses evaporation of sodium chloride to silicon wafer substrates as sacrificial layers, upon which functional lead titanate zirconate ceramic films are grown at 710?°C maximum temperature to validate the method. The freestanding, functional foils are then released by dissolution of the sacrificial sodium chloride in water and have the potential to be integrated into low-thermal stability printed circuits and flexible substrates. The optimization of the sodium chloride layer surface quality and bonding strength with the underlying wafer is achieved thanks to pre-annealing treatment.  相似文献   
70.
The structural and electrochemical properties of the double perovskite-type oxide, PrBaMnMoO6-δ, was investigated using neutron diffraction with in-situ conductivity measurement under a dry Argon atmosphere from 25 °C to 700 °C. A Rietveld refinement of the neutron diffraction data confirmed monoclinic symmetry in the P21/n space group. Rietveld refinement also confirms the unit cell parameters of a = 5.6567 (1) Å, b = 5.6065 (2) Å, c = 7.9344 (1) Å and β = 84.43° with reliable atomic positions and refinement factors (R-factors). Neutron diffraction data refinement shows two minor phases (<5%), an orthorhombic AB2O5 type phase of PrMn2O5 in the Pbam (No. 32) space group with unit cell parameters, a = 7.9672 (1) Å, b = 8.9043 (2) Å and c = 5.8540 (1) Å and a scheelite phase of BaMoO4 in the tetragonal I41/a (88) space group with the unit cell parameters, a = b = 5.9522 (1) Å, and c = 12.3211 (2) Å. Morphological images revealed a porous and intertwined microstructure. In-situ conductivity measurement shows that the total conductivity of this material was 130.84 Scm?1 at 700 °C.  相似文献   
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