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51.
There are many potential causes of corrosion in animal buildings. Animals exhale large quantities of moisture into the air creating high relative humidity in the building if the moisture is not properly vented. High humidity increases the potential for condensation. In addition, ammonia may be found in large quantities in animal buildings. Ammonia is released from manure and urine. In addition, ammonium chloride is used as a nitrogen source in fertilisers. In this study, the atmospheric corrosion of hot-dip-galvanised steel and zinc alloy-coated steel such as zinc–aluminium and zinc–aluminium–magnesium has been studied in atmospheres containing different levels of ammonia. Investigations have also been conducted at different levels of ammonium chloride. The results are discussed in view of the mechanisms of corrosion of zinc and zinc alloy-coated steel in ammonia and ammonium chloride-containing environments.  相似文献   
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This work describes a class of complex combining three dithienylethene units and a lanthanide ion used as an optical system displaying a double encryption method: i) a colorful code, drawn and erased under UV and visible irradiations respectively, due to coloration and discoloration of the photochromic entities, and ii) a concomitant gradual disappearance and progressive restoration of the associated lanthanide ion luminescence triggered with the same stimuli. The innovation of the system stems from the emission color tunability, i.e., with either a lanthanide ion emitting only in the visible range (Eu3+) or with another lanthanide ion emitting only in the near infrared (NIR) range (Yb3+), therefore observable, or not, to the naked eye. This system is the very first one to achieve efficient repeatable modulation of pure NIR luminescence on photochemical command. Furthermore, it is proven to be highly efficient when embedded in a PDMS polymer opening real opportunities for practical applications as anti‐counterfeiting.  相似文献   
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Ru complexes were successfully produced, and their structural properties were investigated using FTIR, Raman, and single crystal XRD patterns. The HOMO, LUMO, Eg, and electronic surface potential (ESP) values of the molecules were calculated by a Gaussian program. The complexes were used for producing hybrid capacitor cells as electrode materials. According to electrochemical analysis, complex 2 showed the best CV graph between ?1 V and +1 V and had the highest current value and hysteresis area when compared with the other complexes. The performance analysis and the capacity fade of the cells were investigated. The first capacity values of the complexes were 57.5, 22.1, 16.9, and 0.0021 F/g for complexes 1 , 2 , 3 , and 4 , respectively. The capacitive mechanism of the cells as relates to molecular interactions was also investigated. We suggested that the ESP values of the molecules were directly related to the capacitive performance of the cells. In addition to this, the best cycling performance was obtained for complex 2, which has the lowest Eg value among the complexes. We speculate that the charged regions on the complex materials have a crucial role in the increasing the capacitance of the cells.  相似文献   
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Odour‐active compounds in muscle of turbot (Psetta maxima) fed experimental diets containing fish oil (FO), soybean oil (SO) or linseed oil (LO) were investigated by a gas chromatography/olfactometry technique. Thirty‐one areas associated with odours were detected in muscle extracts. Among the compounds responsible for these odours, 23 were formed by oxidation of unsaturated fatty acids. Independently of diet, (E)‐2‐penten‐1‐ol and (E)‐3‐hexen‐1‐ol contribute strongly to the odour of turbot. (E,Z)‐2,6‐Nonadienal, (E)‐2‐pentenal and (E,E)‐1,3‐(Z)‐5‐octatriene seem to contribute strongly to the odour of turbot fed diets containing high levels of n‐3 PUFA (FO and LO groups). Hexanal and decanal show a high detection frequency in turbot fed diets containing vegetable oils. Odorous compounds which are not formed by lipid oxidation (methional, 1‐acetyl pyrazine, 4‐ethyl benzaldehyde and 2‐acetyl‐2‐thiazoline) were not affected by dietary lipid sources. © 2001 Society of Chemical Industry  相似文献   
56.
The present work aimed at evaluating the Cucurbita maxima Duchesne defatted seeds flour (CDSF) as fat replacer in beef patty. Pastes obtained from CDSF containing 60 and 72 % water were prepared and used to replace fat in beef patty at 25, 50, 75 and 100 % respectively. A control patty was processed using kidney fat from beef. The proximate composition, technological yield, textural and sensorial properties of different samples were evaluated. Results showed that CDSF contains 77.76/100 g proteins based on dried matter. Protein content of patty increased with fat substitution rates (FSR) from 18.82/100 g wet matter (WM) to 23.24/100 g WM respectively for the control (P0) and the sample in which fat was substituted at 100 % with the CDSF paste with a water content of 60 % (P460). The lipid content dropped with the increase in the fat substitution rate and water content of CDSF paste from 10.70/100 to 0.28/100 g WM respectively for the sample in which fat was substituted at 25 % with the CDSF paste with a water content of 60 % (P160) and the sample in which fat was substituted at 100 % with the CDSF paste containing 72 % water (P472). Similarly, hardness dropped from 54.78 N (P0) to 37.56 N (P472) respectively. The cooking yield increased significantly (p < 0.05) with the increase in the water content of the CDSF paste and the fat substitution rate. From the sensory analysis, patties with 75 and 100 % of FSR were the most accepted. Thus, the CDSF paste can be used in beef patty as a fat replacer to reduce the detrimental effect of animal fat consumption.  相似文献   
57.
We report here the DNA sequence of a segment of chromosome III extending over 8.2 kb. The sequence was determined using the random clone strategy followed by oligonucleotide-directed sequencing. The segment contains five long open reading frames, YCR521, 522, 523, 524 and 526, with only short distances between them. YCR523 (333 codons) encodes a ribokinase, a new function for yeast. YCR526 originates inside the MAT cassette, which is in continuity with the present segment, and extends over 358 codons outside of MAT. YCR524 (923 codons) codes for a putative membrane protein. YCR521, 522 and 524, have each been disrupted by insertion of a URA3 cassette and are non-essential genes. An active ARS element is located within YCR523 or its vicinity.  相似文献   
58.
The high resolution complete physical maps of chromosomes VII and XV were constructed to form the basis for sequencing these chromosomes as part of the European systematic sequencing programme of the yeast genome, using a unique cosmid library from strain FY1679, and an original top-down mapping strategy involving I-Sce I chromosome fragmentation. A total of 138 and 196 cosmid clones were used to construct the maps for VII and XV, respectively, forming two unique contigs that cover the entirety of chromosomes (1091 kb each), except the telomeric repeats. Colinearity of the cosmid inserts with yeast DNA was verified, and the physical maps were eventually compared with the independently generated genetic maps. © 1998 John Wiley & Sons, Ltd.  相似文献   
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