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31.
Hybrid extraction replication has been used to prepare TEM samples from laser-drilled coupons of the Ni-based superalloy IN100. In addition to extracting the inert carbide and boride particles, these carbon replicas reveal the microstructure of the surrounding metallic phases allowing the particle distribution to be studied. It is shown that the IN100 base metal contains large (> 100 nm) MC, M23C6 and M3B2 particles, consistent with previous TEM studies on this alloy. In the recast layers on the interior surfaces of the laser-drilled holes, however, dendritic micro-segregation in the supersaturated γ phase gives a cellular sub-structure, and the inert particles observed are nano-scale Ti-rich MC-type carbides at the cell boundaries. The replicas also reveal that the base metal/recast interface is abrupt. These observations illustrate the power of the hybrid replication technique for revealing variations in nano-scale features over much larger length scales (? 10 μm).  相似文献   
32.
The objective of this research was to study the effect of osmotic pretreatment with combined anti-browning agents (acid, glycerol and/or trehalose) on the colour characteristics of dried litchi after drying and during 5 months of storage compared to samples without pretreatment. The pretreated samples showed good inhibition of polyphenol oxidase activity when compared with the control, while the total phenolic contents in the dried products were not reduced. The results demonstrated that water activity, lightness difference, chroma, degree of browning (DB), and 5-hydroxymethylfurfural values of all pretreated samples increased, while hue angle decreased with storage time. Samples pretreated with glycerol showed the best potential for browning retardation, followed by glycerol combined with trehalose, and trehalose, respectively. In addition, the colour parameters were used to calculate the luminescence values, representing the data in grey scale, which were correlated with a non-enzymatic browning index. The results showed grey value could be adequately used to represent the DB of dried litchi with r 2 value of 0.92.  相似文献   
33.
After contact with a rabies-infected rabbit, 31 Persons were submitted to complete vaccination treatment with duck embryo vaccine, comprising of injections of 1.0 ml each every fast night and two booster injections of 1.0 ml each, which were administered 10 and 20 days, respectively, after the end of the 14 days' vaccination series. After performance of intracutaneous and ophthalmic tests, 18 children received heterologous rabies immunserum (Behring) in a dose of 0.2 ml per kg of body weight before the beginning of the vaccination series. Six weeks after the start of the vaccination series neutralizing and complement-fixing antibodies (rate of conversion 100 per cent) were detected in all patients. The mean titre of neutralizing antibodies (mouse test 200 LD 50 Fixed virus, strain CVS) amounted to 1:140, that of complement-fixing antibodies to 1:41. Severe incompatibility reactions were not observed. Outpatient treatment with duck embryo vaccine therefore seems to be fully justified.  相似文献   
34.
Posits that an adequate explanation of psychological phenomena that have a conscious aspect implies a theory of awareness that is now lacking. On psychological, physical, and philosophical grounds, a preliminary model is presented, postulating awareness as a field effect with 2 primary modes: detector and effector. Any adequate field theory of awareness seems to entail a set of field equations; an outline of preconditions for their eventual derivation is presented, partially based on C. T. Tart's (1975) paradigm for the experimental investigation of consciousness. It is argued that the field paradigm of physics provides a fruitful precedent for dealing with an unobservable event having observable consequences. (French abstract) (36 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
35.
Over a 4-year period 40,923 operations and 44,716 surgical admissions were monitored for both community and hospital onset infections. One thousand eight hundred sixty-five patients had 1966 surgical wound infections and 2056 remote infections including 1652 hospital onset and 404 community onset infections. One thousand one hudnred forty-four patients with multiple infections averaged 40 days in the hospital contrasted with 24 days for 721 patients with a single wound infection. The total excess cost of hospitalization for these patients was $951,150. A statistically significant reduction occurred for urinary tract infections, lower respiratory infections and clean and contaminated surgical wound infections. It is suggested that these are all inter-related and a significant reduction in surgical wound infections can be achieved through control of infections at remote sites, particularly those associated with medical devices. The coagulase positive staphylococcus is still the most important single bacterial species in the primary etiology of surgical wound infections. When the gastrointestinal tract is entered or "supra" infecting organisms appear, gram negative bacteria and mixed gram negative and gram positive infections are dominant. Reduction in remote site infections occurring in surgical patients is necessary to reduce the incidence of surgical wound infections, suggest preventive and control measures, and document the effectiveness of such measures.  相似文献   
36.
Fatigue crack initiation in Al 2219-T851 for fully reversed loading(R = σ/σmax =?1) parallel to the material rolling direction is found to occur at intermetallic inclusions at the specimen surface. The inclusions are not involved in crack initiation for fatigue perpendicular to the rolling direction, and for this orientation crack initiation is at grain boundaries and specimens have an increased fatigue life. Except for fatigue at low peak stress, multiple numbers of microcracks are formed and for selected failed specimens the number of cracks has been determined as a function of crack length. Such crack length distribution measurements show that there is significant retardation of microcracks by interaction with grain boundaries. Furthermore it is found that the coalescence of microcracks provides a mechanism for cracking to “jump“ grain boundaries and reduce fatigue lifetime. The effect of relative humidity on this process is to increase the observed mean crack length, and decrease the number of crack initiations apparently due to weakening of the matrix-intermetallic interface at potential initiation sites. The overall result is that no significant dependence of fatigue life on relative humidity is found.  相似文献   
37.
Fatigue crack initiation in Al 2219-T851 for fully reversed loading(R = σ/σmax =−1) parallel to the material rolling direction is found to occur at intermetallic inclusions at the specimen surface. The inclusions are not involved in crack initiation for fatigue perpendicular to the rolling direction, and for this orientation crack initiation is at grain boundaries and specimens have an increased fatigue life. Except for fatigue at low peak stress, multiple numbers of microcracks are formed and for selected failed specimens the number of cracks has been determined as a function of crack length. Such crack length distribution measurements show that there is significant retardation of microcracks by interaction with grain boundaries. Furthermore it is found that the coalescence of microcracks provides a mechanism for cracking to “jump“ grain boundaries and reduce fatigue lifetime. The effect of relative humidity on this process is to increase the observed mean crack length, and decrease the number of crack initiations apparently due to weakening of the matrix-intermetallic interface at potential initiation sites. The overall result is that no significant dependence of fatigue life on relative humidity is found. Formerly with the Science Center, Rock-well International  相似文献   
38.
Sugarcane spirit is the most consumed distilled beverage in Brazil. Currently the manufacturing industries are trying to widen their market and attract new consumers, and thus it has become necessary to elevate the product to national and international quality standards. This study's aim was to determine the influence of subsequent distillations on the composition of organic sugarcane spirit. From mono‐distilled organic sugarcane spirit, bi‐, tri‐, tetra‐ and penta‐distilled sugarcane spirits were obtained, and analysed for the following: relative density, alcoholic degree, volatile acidity, pH, copper, methanol, aldehydes, furfural, esters, ethyl carbamate and higher alcohols. The most relevant results were reductions of 69.57% volatile acidity, 98.4% copper, 40.9% methanol, 71.5% aldehydes, 100% esters, 100% ethyl carbamate and 32.2% higher alcohols in the penta‐distilled sugarcane spirit, as compared with the mono‐distilled. It was concluded that subsequent distillations would put sugarcane spirit in line with the international standards for distilled beverages. Copyright © 2013 The Institute of Brewing & Distilling  相似文献   
39.
40.
Coconut is grown in tropical and subtropical areas worldwide. The endosperm (water and meat) is consumed and processed in different forms. This study investigated the antioxidant activities and identified the phenolic compounds existing in the water and meat of coconut fruits at three different maturity stages, i.e., 180, 190, and 225 days after pollination from two planting areas in Thailand. Total phenolic content and antioxidant activity indices increased as the coconut matured from 180 to 190 days after pollination and then decreased or remained unchanged at 225 days after pollination. Catechin and salicylic acid were the major phenolic compounds found in the water, while gallic, caffeic, salicylic, and p-coumaric acids were found in the meat. The fat content of the meat increased significantly with maturity stage. Medium chain fatty acids profiles were also analyzed. The results are important for producers, processors, and consumers to realize an optimal quality and functionality of coconut water and meat when used for specific purposes.  相似文献   
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