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71.
Gaona-Martínez Mauro J. Guajardo-López Laura N. Pérez-Patiño Juan A. Ramírez-Ramírez Javier H. Pérez-González Francisco A. Colás Rafael Garza-Montes-de-Oca Nelson F. 《Oxidation of Metals》2019,91(5-6):641-656
Oxidation of Metals - The oxidation characteristics of a roll-grade high-speed steel with different tempering heat treatments were studied under thermal cycling conditions at 650 °C... 相似文献
72.
The effect of photodegradation on the properties of multilayer polyethylene slabs was evaluated. It was found that photodegradation causes an increase in the degree of crystallinity accompanied by an increase in the elastic modulus and a decrease in elongation and oxygen permeability. It was shown that oxygen and not UV light is the controlling factor in the photodegradation process. © 1996 John Wiley & Sons, Inc. 相似文献
73.
An investigation was made into the dielectric spectroscopic characteristics of p-toluene sulfonate (PTS) doped polypyrrole (PPY) films in the presence and absence of immobilized glucose oxidase (GOX) in three different configurations: Al-PTS-PPY-Al-PTS-PPY/GOX-Al, and Al-PTS-PPY/GOX/β-D -glucose-Al, respectively. Measurement of dielectric loss and capacitance yielded valuable information about the dielectric properties of GOX immobilized in PTS doped PPY films. The effect of both the temperature and varying βD -glucose concentrations on the mobility of the charge carriers in these films was also systematically studied. © 1996 John Wiley & Sons, Inc. 相似文献
74.
K.M. Gangotri Om Prakash Regar Chhagan Lal Prashant Kalla Kishna Ram Genwa Rajni Meena 《国际能源研究杂志》1996,20(7):581-585
Photogalvanic effects were studied in a photogalvanic cell containing toluidine blue, glucose and tergitol-7 as a photosensitizer, reductant and surfactant, respectively. The photocurrent and photopotential generated by this system were 70 μA and 315 mV, respectively. The effects of different parameters on the electrical output of the cell were observed. Current/voltage characteristics of the cell have also been studied, and a mechanism has been proposed for the generation of photocurrent in photogalvanic cell. 相似文献
75.
Vishnu Ji Ram 《Advanced Synthesis \u0026amp; Catalysis》1989,331(6):893-905
Various bicyclic ( 2 , 3 ) and tricyclic ( 4 , 5 ) heterocycles were prepared by the reaction of 1a , c with dihaloalkanes and polynitrohalobenzene separately. Electrophilic substitution on 1a–c with different alkyl halides yielded mono and dialkyl pyrimidiens ( 6–20 ). Nucleophilic substitution reactions on 18 and 21 with amine and hydrazine separately yielded 22–31 , 21a , b and 41c . Reaction of 25a with ethyl ethoxymethylenecyanoacetate and chloroacetyl chloride separately provided bicyclic compounds 32 and 33 . Condensation-cyclization of 25a with formic, acetic and nitrous acid separately yielded 34a , b and 35 . Reaction of 26a with ethylthiocylycolate and thiourea separately provided 36a and 39 . The latter was alkylated with methyl iodide to 40 . An attempt to cyclize 29a and 30a with thionyl chloride provided bicyclic compounds 37a , b and an uncyclic product 38 . Some of the compounds were screened for leishmanicidal and herbicidal activities and a few of them exhibited significant activity. Leishmaniasis is considered to be one of the most devastating diseases and is ominous to tropical countries. The high toxicity of leishmanicidal drugs in current use, aroused considerable interest to develop new safer and effective chemotherapeutic agents. The only drug pyrimethamine [2] is the representative of pyrimidine derivatives, known as leishmanicides but low order of activity at high dose failed to retain in the clinic. Based on our past experiences in rational designing of leishmanicidal pyrimidine analogs, incorporation of levamisole pharmacophore either in flexible or rigid forms is indispensable for potential activity [1,3] against visceral leishmaniasis. These observations induced an impetus to synthesize pyrimidine analogs as potential leishmanicides. 相似文献
76.
Processing polyimide-based thermosetting matrix composites is complicated because of gaseous volatiles produced during the polymerization and crosslinking reactions. This process involves complex interactions between part geometry, temperature and force cycles, and matrix/fiber properties. A simple model for the consolidation process that treats these composites as a three-phase system consisting of fiber, resin, and volatile has been developed. This model has been applied to compression molding process for constant thickness laminates and the predictions agree well with experiments. Further extension to handle three-dimensional parts and the required numerical techniques have also been developed. 相似文献
77.
An analytical procedure, developed to simulate the graphic method for the design of vessels subjected to external pressure or vacuum, suggested by the ASME Code, Section VIII, Division 1, is presented in this contribution. A comprehensive computer program based on this method is also presented. The program also covers the design of stiffener rings. The procedure can be easily extended to include other international standards such as the British and German codes, since the method is based on the concept of the number of lobes at collapse. The method produced reproducible results over the entire range of L/D0 and D0/t ratios of the code. The deviation observed at any point in this range is less than 0.5% for factor A. The variation in allowable pressure is less than 2%. 相似文献
78.
Delphine Vincent AnhDuyen Bui Doris Ram Vilnis Ezernieks Frank Bedon Joe Panozzo Pankaj Maharjan Simone Rochfort Hans Daetwyler Matthew Hayden 《International journal of molecular sciences》2022,23(2)
Bread wheat is the most widely cultivated crop worldwide, used in the production of food products and a feed source for animals. Selection tools that can be applied early in the breeding cycle are needed to accelerate genetic gain for increased wheat production while maintaining or improving grain quality if demand from human population growth is to be fulfilled. Proteomics screening assays of wheat flour can assist breeders to select the best performing breeding lines and discard the worst lines. In this study, we optimised a robust LC–MS shotgun quantitative proteomics method to screen thousands of wheat genotypes. Using 6 cultivars and 4 replicates, we tested 3 resuspension ratios (50, 25, and 17 µL/mg), 2 extraction buffers (with urea or guanidine-hydrochloride), 3 sets of proteases (chymotrypsin, Glu-C, and trypsin/Lys-C), and multiple LC settings. Protein identifications by LC–MS/MS were used to select the best parameters. A total 8738 wheat proteins were identified. The best method was validated on an independent set of 96 cultivars and peptides quantities were normalised using sample weights, an internal standard, and quality controls. Data mining tools found particularly useful to explore the flour proteome are presented (UniProt Retrieve/ID mapping tool, KEGG, AgriGO, REVIGO, and Pathway Tools). 相似文献
79.
Valdezate S Arroyo M González-Sanz R Ramíro R Herrera-León S Usera MA De la Fuente M Echeita A 《Journal of food protection》2007,70(12):2741-2748
The aims of this study were to ascertain the population structure and antimicrobial susceptibility of Salmonella enterica serovars isolated in 2002 from food in 16 Spanish regions. Serovars were characterized by serotyping, phage typing, antimicrobial susceptibility, and pulsed-field gel electrophoresis (PFGE) typing, and 264 nonrelated strains were selected for further analysis. The main sources were eggs and their derivatives (21.6% of strains), poultry and related products (16.6%), and seafood (16.3%). High serotype diversity was detected (51 serotypes); the most common were Enteritidis (n = 96, 36.3%) and Typhimurium (n = 53, 20.1%), followed by a miscellaneous group of 49 different serotypes (n = 115, 43.5%). A 15% increase in Salmonella Enteritidis isolation was observed. Common phage types for Salmonella Enteritidis were PT1 (41.6% of isolates), PT4 (9.4%), PT6 (9.4%), and PT6a (9.4%), and common types for Salmonella Typhimurium were DTU302 (18.8%), DT104 (15.1%), and DT104B (13.2%). Salmonella Enteritidis strains were categorized into eight PFGE types with a similarity of 81 to 96%, and 73.9% of the strains were grouped into just one cluster. Salmonella Typhimurium isolates were divided into 13 PFGE types with a similarity of 64 to 86%, and one predominant clone contained 41.5% of the strains. Resistance rates for Salmonella Enteritidis, Salmonella Typhimurium, and the miscellaneous group were, respectively, 8.3, 69.8, and 13.9% for ampicillin, 3.1, 52.8, and 59% for streptomycin, 40.6, 22.6, and 10.4% for nalidixic acid, 15.6, 71.7, and 31.1% for tetracycline, 7.3, 18.8, and 9.5% for trimethoprim-sulfamethoxazole, 0, 50.9, and 4.3% for chloramphenicol, and 6.2, 71.7, and 17.4% for multiple (at least four) antimicrobials. All the strains remained susceptible to other beta-lactams and fluoroquinolones. Surveillance of S. enterica isolated from food is strongly recommended to reduce community exposure to antimicrobial resistant strains. 相似文献
80.
Effects of dietary supplements of zinc-methionine on milk production,udder health and zinc metabolism in dairy goats 总被引:5,自引:0,他引:5
Salama AA Caja G Albanell E Such X Casals R Plaixats J 《The Journal of dairy research》2003,70(1):9-17
Twenty-two Murciano-Granadina dairy goats were used to investigate the effects of organic Zn supplementation of a diet containing a high level of inorganic Zn. Goats were kept in pens, machine milked once a day throughout lactation and fed a diet based on a dehydrated mixture of whole-plant maize and alfalfa ad libitum, alfalfa pellets, barley grain and a concentrate mixture. Treatments were: (1) control, and (2) supplemented with 1 g/d Zn-Methionine (Zn-Met) included in the concentrate mixture. After parturition, goats were blocked in week 3 and dietary treatments were applied until week 23. From weeks 3-20, feed intake, milk yield, milk composition, milk somatic cell count (SCC), and udder health were measured. In week 21, all goats were injected intraperitoneally with 1 g/d DL-methionine for 5 d to establish the effects of methionine under the conditions of udder stress induced by hand milking on the second day. During weeks 22 and 23, diet digestibility, and N and Zn balance were determined. Dry matter intake, milk yield, and milk contents of total solids, fat, total and true protein, and casein did not differ between treatments, but whey protein and non-protein nitrogen contents were significantly lower for the Zn-Met group. Milk SCC tended to decrease as a result of Zn-Met supplementation but differences between treatments were not significant when halves with persistent infection were excluded. Hand milking increased SCC in both groups, but udders of supplemented goats showed a lower reaction. Apparent absorption of N significantly increased and Zn retention tended to increase in Zn-Met supplemented goats. We conclude that Zn-Met supplementation can enhance resistance to udder stress in dairy goats. Effects were attributed to the organic Zn and not to the methionine component. Zn retention and protein utilization were also improved by the Zn-Met supplement. 相似文献