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951.
Lior Miller Amir Avishai Wayne D. Kaplan 《Journal of the American Ceramic Society》2006,89(1):350-353
The solubility of Mg in alumina was measured using wavelength-dispersive spectroscopy mounted on a scanning electron microscope. Careful calibration of the microscope's working conditions was performed in order to optimize the detection limit and accuracy. Measurements were conducted on water-quenched and furnace-cooled samples, without any thermal or chemical etching to avoid alteration of the bulk concentration. The results indicate the solubility limit of Mg in alumina to be 132±11 ppm at 1600°C. 相似文献
952.
Forty-eight fresh hams and bellies were obtained from 24 market weight hogs (x = 94·5 kg) of which twelve were electrically stimulated (ES) by pulsing current immediately after exsanguination. The left side of each non-stimulated (NS) carcas was fabricated after conditioning for 3h post mortem at 17°C (NS hot-processed). The left sides of ES carcasses were fabricated 1 h pm. The right sides were fabricated following a 24 h cooler chill at 2°C (conventionally chilled: CP). Hams from ESCP carcasses had higher (P < 0·05) smokehouse yields than hams from NS carcasses. Hams that were hot-processed had higher smokehouse yields than the NSCP hams. Time of fabrication (1, 3 or 24h post mortem) did not affect smokehouse yields. Conventionally chilled bellies obtained from ES carcasses showed higher (P < 0·05) residual nitrite levels than those front electrically stimulated hot-processed (ESHP) carcasses. No differences were found for residual nitrite levels in the non-electrically stimulated sides. Panelists were unable to detect any sensory differences from the bacon strips. Sensory scores of ham slices were more juicy for non-stimulated hot-processed carcasses (NSHP) than those from ESHP carcasses. Panelists found the ham slices from NSCP carcasses to be more tender (P < 0·05) than those from electrically stimulated cold-processed (ESCP) carcasses. Results from this study clearly indicated that hot-processing of pork can provide hams and bellies that are acceptable for the production of cured hams and bacon of comparable quality and yield to those currently being produced under conventional processing methods. 相似文献
953.
Koren U. Miller B.I. Tucker R.S. Eisenstein G. Bar-Joseph I. Miller D.A.B. Chemla D.S. 《Electronics letters》1987,23(12):621-622
We describe the structure and performance characteristics of an InGaAs/InP multiple-quantum-well (MQW) electro-absorption buried-mesa optical modulator. The device is fabricated with two metal-organic chemical-vapour-deposition (MOCVD) growth steps, wherein small-area circular (40?m diameter) PIN diodes are buried with Fe-doped semiinsulating (SI) InP regrowth. The modulator has a relatively low insertion loss (4.5 dB) with 25% modulation depth and very high modulation bandwith (5.3 GHz) operating at 1.62?m wavelength. 相似文献
954.
955.
Cellulose can be totally liquefied by heating to 350 °C in the presence of an aqueous phenolic solvent containing a catalyst. The main products are light aromatic hydrocarbons, benzofurans, heavier aromatic hydrocarbons such as substituted indanes and tetralin, and xanthenes. The variation of product distribution with catalyst was examined and it was found that in aqueous phenol, xanthene formation was enhanced by acidity. By substituting guaiacol for phenol, it was determined that most benzofuran formation involved the phenol solvent molecules, although a small proportion did not. This benzofuran may have arises from phenol generated from cellulose, the incorporation of phenol in the products being enhanced through a cage effect. 相似文献
956.
Robert D. Miller 《Advanced materials (Deerfield Beach, Fla.)》1989,1(12):433-440
In spite of the fact that the first polysilane derivatives were probably prepared in the mid 1920's, there was little scientific interest until recently. The synthesis of the first soluble homo and copolymers about 10 years ago has stimulated an explosive development of this class of materials. This brief review traces the historical development of the polysilanes and focuses on recent studies of polymer structure, electronic properties, photochemical reactions and mechanisms and finally on new applications. 相似文献
957.
Bushman Brad J.; Bonacci Angelica M.; Pedersen William C.; Vasquez Eduardo A.; Miller Norman 《Canadian Metallurgical Quarterly》2005,88(6):969
Ruminating about a provocation increases the likelihood of displaced aggression following a minor annoyance (trigger). In Study 1, provoked participants who ruminated for 25 min were more aggressive toward a fumbling confederate than were distracted participants. Provocation-induced negative affect was positively related to aggression but only among those who ruminated. Study 2 conceptually replicated Study 1 and also found that the more negatively people reacted to the trigger, the more likely the trigger was to increase displaced aggression. Study 3 replicated the findings of Studies 1 and 2 by using an 8-hr rumination period. All 3 studies suggest that ruminating about a provocation increases the likelihood that a minor triggering annoyance will increase displaced aggression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
958.
959.
LJ van Rijn MP ten Tusscher I de Jong F Hendrikse 《Canadian Metallurgical Quarterly》1998,38(19):2973-2978
We measured the symmetry of phoria angles in six normal subjects. Subjects were selected on the basis of good visual acuity and stereopsis, normal binocular eye alignment and, apart from mild refraction errors, absence of ocular abnormalities. They were instructed to look at a word on a reading chart at 2 m distance. Each measurement consisted of five subsequent intervals of 5 s duration. During these five intervals viewing was binocular, with the right eye only, binocular, with the left eye only, and binocular, respectively. Each experiment consisted of twelve measurements. Eye movements were measured with scleral coils suited for measuring in horizontal, vertical and torsional directions. Five out of six subjects displayed an asymmetrical vertical phoria; one subject showed an alternating hyperphoria; four displayed a left over right vertical phoria that was largest for left eye occlusion. Only one subject showed a symmetrical vertical phoria. Both the size of the vertical phorias and the size of the asymmetries in these vertical phorias were very small: on average 0.16 +/- 0.01 and 0.17 +/- 0.01 degree, respectively. The direction of the vertical phoria asymmetries (the largest left over right was found with left eye occlusion) and the fact that asymmetries were found more often in vertical than horizontal and torsional phorias suggest that these asymmetries are related to dissociated vertical deviation. These results suggest that dissociated vertical deviation, often observed in subjects with a disruption of binocular vision early in life, reflects the enhancement of a phenomenon that is present in normal subjects as well. 相似文献
960.
SH Miller 《Canadian Metallurgical Quarterly》1998,101(5):1389-1399
Economic constraints developing as a result of rising health care costs in the United States pose significant challenges for and threats to the survival of academic plastic surgery. Declining clinical revenues, competition for patients and resources from other health care providers, and reductions in support of its education and research efforts necessitate a paradigm shift if it is to survive. Questionnaires were used to collect data from 92 of the 100 postgraduate training program directors of plastic surgery in the United States. The most common source of clinical income on a national basis was indemnity insurance. Sources of clinical income varied by region. The majority of programs, 80 percent, report that at least 75 percent of the income support for faculty came from practice income. Financial support for ancillary and research personnel, in large part, came from this same source. Resident salaries and benefits came largely from other resources. Generally as population density within the metropolitan area in which a program was located increased, so too did the number of competing plastic surgeons, including graduates of the program and nonacademic cosmetic and hand surgeons. However, levels of competition for cosmetic surgery in smaller metropolitan areas of some regions seem to be similar to those reported by programs in larger communities. Plastic surgery programs in very competitive communities received significantly greater amounts of their income from indemnity insurance and self-paying patients than did programs in less competitive metropolitan areas. Internal competition from other surgical and nonsurgical specialists within the same institution is likewise keen. Virtually all respondents, 93 percent, report that their institutions provided patient care in a least one designated center of excellence in the following disciplines: hand, microsurgery, craniofacial, cleft lip and palate, burn, and cosmetic surgery. This study suggests that centers of excellence are more likely to be present in metropolitan areas with fewer competing surgeons than in areas with large numbers of competing surgeons. The data did not demonstrate that the presence of a center of excellence substantially affected the sources or levels of clinical income. To survive as an academic entity, program directors must correctly perceive and fulfill the needs and wants of its stakeholders, particularly with regard to quality of life issues. 相似文献