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21.
Spectrophotometers are routinely used for color measurement and color management in many commercial printing and proofing workflows. In the case of media containing optical brightening agents, ultraviolet (UV)‐induced fluorescence has led to poor levels of agreement between models from different manufacturers, and different models from the same manufacturer. A relevant standard, ISO 13655, has been revised and now clearly defines measurement modes and conditions for the UV component in spectrophotometers. ISO 13655:2009—Graphic Technology—Spectral Measurement and Colorimetric Computation for Graphic Arts Images now defines four measurement modes: M0, M1, M2, and M3. The intermodel difference between 10 commercially available spectrophotometers is evaluated for different substrate types in measurement modes (M0, M1, and M2) as allowed by each instrument. In particular, the authors compare devices using M0 legacy mode versus newer instruments that are compliant with the new M1 and M2 (UV‐included and UV‐excluded) measurement modes. A finding with significant practical applications is that there is greatly improved intermodel agreement between the new generation of ISO 13655‐compliant instruments in M1 (D50) mode when compared with the previous generation of hand‐held spectrophotometers. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 27–37, 2017  相似文献   
22.
Austenitic stainless steel AISI 321 is used to fabricate plumbing lines to transfer cryogens from storage to output collector of propulsion system. Cracks were found in some of such tubes during one of the qualification tests of pipelines. The crack occurred at the bent region of the fuel feed pipeline along its neutral axis. Detailed metallographic investigations revealed presence of numerous longitudinal fine cracks on the inner surface of the tube that resulted from improper extrusion of the tube. Further, deformation induced martensitic transformation occurred, as the tube was bent at liquid nitrogen temperature. The transformed martensite, in presence of fine cracks on inner surface of the tube, due to improper extrusion, resulted in crack opening. This paper highlights the details of investigations carried out.  相似文献   
23.
0.15C–1.25Cr–1Mo–0.25V steel, a high strength low alloy (HSLA) steel, is being extensively used in space programme. This alloy being a versatile material and its ease of fabrication and welding made it the most suitable for the fabrication of 560 mm dia pressure vessel for smaller rockets. During proof pressure test for 73 KSC, one of the pressure vessels burst opened at 71 KSC. Metallurgical analysis of the failed motor case was carried out to understand the causes of its failure. Observations indicated that a deviation in normal heat treatment resulted in low strength of material, which caused yielding and premature rupture at lower pressure than expected. This paper brings out the salient features of this analysis.  相似文献   
24.
Titanium alloy fasteners are being used in space programme. These fasteners are coated with MoS2, which serves the purpose of solid lubricant. During the trial assembly of flight spin motor to the bracket mounted on subsystem, one of the two fasteners failed such that the head of the bolt had sheared off the shank. Metallographic analysis carried out on the failed fasteners revealed variations in the microstructures all along the shank axis. Microstructure consisted of equiaxed primary alpha in transformed beta matrix within lower portion of the shank, while it was elongated primary alpha with little bulging all along prior beta grain boundaries as well as acicular alpha at some other location towards the head side, features, typical of, as if worked above beta transus temperatures.This paper highlights the details of investigations carried out on the failed fasteners.  相似文献   
25.
Classification of spatially distributed measurements in industrial processes is often a difficult task. A typical example is given by the interpretation of the gas temperatures from horizontal probes in blast furnaces. This paper presents a neural network-based classification of temperature measurements from an above-burden probe. An expert on blast furnace supervision and control first classified a large set of temperature profiles into six different stereotype patterns. Roughly 40 % of this material was used for training feedforward neural networks, while the remaining profiles were used for evaluation of the networks' performance in order to determine an appropriate network size. In general, consensus was found among the networks in that similar erroneous or inconsistent classifications made by the human expert were detected. However, the network size clearly affected the quality of the classifications. The work demonstrated the merits of a rapid, consistent, and automatic (neural) interpretation, as well as the risk of misclassification and the subjectivity involved when human experts have to evaluate complex patterns.  相似文献   
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Cao H  Dong Y  O'Rorke S  Wang W  Pandit A 《Nanotechnology》2011,22(6):065604
The synthesis of a new PEG based hyperbranched copolymer of poly(ethylene glycol) methyl ether methacrylate-co-ethylene glycol dimethacrylate (PEGMEMA-co-EGDMA) was achieved via a one-step in situ deactivation enhanced atom transfer radical polymerization (DE-ATRP). Then, hollow PEG based nanospheres were fabricated from this polymer using a solvent evaporation method and post-stabilisation strategy. Furthermore, the analysis using a cellular metabolic activity assay proved that the copolymer did not affect cellular metabolism, indicating that this PEG based polymeric nanosphere has potential for use in drug delivery applications.  相似文献   
28.
Ninety nine mine water discharge samples were collected and analyzed for pH, electrical conductivity (EC), major cations, anions, and trace metals in the Pootkee-Balihari coal mining area of the Jharia coalfield. The mines of the area annually discharge 34.80 × 106 m3 of mine water and 39,099 t of solute loads. The pH of the analyzed mine waters ranged from 6.97 to 8.62. EC values ranged from 711 μS cm−1 to 1862 μS cm−1, and reflect variations in lithology, geochemical processes, and hydrological regimes in the mines. The cation and anion chemistry indicate the general ionic abundance as: Mg2+ > Ca2+ > Na+ > K+ and HCO3  > SO4 2− > Cl > NO3  > F, respectively. Elevated SO4 2− concentrations in the Gopalichuck, Kendwadih, and Kachhi-Balihari mine waters are attributed to pyrite weathering. The water quality assessment indicated that TDS, hardness, Mg2+, and SO4 2− are the major parameters of concern in the study area. Except for Fe, all of the measured metals in the mine water were well within the levels recommended for drinking water. With only a few exceptions, the mine water is of good to permissible quality and suitable for irrigation.  相似文献   
29.
The fabrication and characteristics of multilayer film C-R-NC filters are discussed. The results of experimental study are found to be in good agreement with the theory. The circuit is suitable for fabrication in hybrid integrated circuit technology as it yields better performance than equivalent R-C-NR structures in certain active configurations.  相似文献   
30.
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