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排序方式: 共有3228条查询结果,搜索用时 109 毫秒
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NE Aronson GW Wortmann SC Johnson JE Jackson RA Gasser AJ Magill TP Endy PE Coyne M Grogl PM Benson JS Beard JD Tally JM Gambel RD Kreutzer CN Oster 《Canadian Metallurgical Quarterly》1998,27(6):1457-1464
The efficacy and toxicity of sodium stibogluconate (SSG) at a dosage of 20 mg/(kg.d) for either 20 days (for cutaneous disease) or 28 days (for visceral, mucosal, or viscerotropic disease) in the treatment of leishmaniasis is reported. Ninety-six U.S. Department of Defense health care beneficiaries with parasitologically confirmed leishmaniasis were prospectively followed for 1 year. One patient was infected with human immunodeficiency virus; otherwise, comorbidity was absent. Clinical cure occurred in 91% of 83 cases of cutaneous disease and 93% of 13 cases of visceral/viscerotropic disease. Adverse effects were common and necessitated interruption of treatment in 28% of cases, but they were generally reversible. These included arthralgias and myalgias (58%), pancreatitis (97%), transaminitis (67%), headache (22%), hematologic suppression (44%), and rash (9%). No subsequent mucosal leishmaniasis was identified, and there were no deaths attributable to SSG or leishmaniasis. 相似文献
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Wang Y Cannon FS Komarneni S Voigt RC Furness JC 《Environmental science & technology》2005,39(19):7712-7718
Prior full-scale foundry data have shown that when an advanced oxidation (AO) process is employed in a green sand system, the foundry needs 20-35% less makeup bentonite clay than when AO is not employed. We herein sought to explore the mechanism of this enhancement and found that AO water displaced the carbon coating of pyrolyzed carbonaceous condensates that otherwise accumulated on the bentonite surface. This was discerned by surface elemental analysis. This AO treatment restored the clay's capacity to adsorb methylene blue (as a measure of its surface charge) and water vapor (as a reflection of its hydrophilic character). In full-scale foundries, these parameters have been tied to improved green compressive strength and mold performance. When baghouse dust from a full-scale foundry received ultrasonic treatment in the lab, 25-30% of the dust classified into the clay-size fraction, whereas only 7% classified this way without ultrasonics. Also, the ultrasonication caused a size reduction of the bentonite due to the delamination of bentonite particles. The average bentonite particle diameter decreased from 4.6 to 3 microm, while the light-scattering surface area increased over 50% after 20 min ultrasonication. This would greatly improve the bonding efficiency of the bentonite according to the classical clay bonding mechanism. As a combined result of these mechanisms, the reduced bentonite consumption in full-scale foundries could be accounted for. 相似文献
945.
Evaluation of volatile hydrocarbon emission characteristics of carbonaceous additives in green sand foundries 总被引:3,自引:0,他引:3
Wang Y Huang H Cannon FS Voigt RC Komarneni S Furness JC 《Environmental science & technology》2007,41(8):2957-2963
This research studied a relative comparison of the hydrocarbon emissions during pyrolysis of four carbonaceous additives that can be used in green sand foundries. These included a highly volatile bituminous coal, anthracite, lignite, and cellulose. Analytic pyrolysis was conducted to simulate the heating conditions that the carbonaceous additives would experience during metal pouring. Specifically, the samples were flash pyrolyzed in a Curie-point pyrolyzer at 920 degrees C with a heating rate of about 3000 degrees C/sec. This simulated some key features of the fast heating conditions that the carbonaceous additives would experience at the metal-mold interface when molten metal is poured into green sand molds. The samples were also pyrolyzed in a thermogravimetric analyzer (TGA) from ambient temperature to 1000 degrees C with a heating rate of 20 degrees C/min; and this simulated key features of the slow heating conditions that the carbonaceous additives would experience within the bulk of green sand molds that is further away from the metal-mold interface. Hydrocarbon emissions from flash pyrolysis were analyzed with GC-FID, while those from TGA pyrolysis were monitored with mass spectroscopy and GC-FID. The anthracite exhibited very low volatile hydrocarbons during both flash pyrolysis and TGA pyrolysis. The cellulose released less hydrocarbons than bituminous coal or lignite in TGA pyrolysis, but more hydrocarbons than those two during flash pyrolysis. This means that cellulose can release sufficient volatile hydrocarbons at the intensely heated molten metal-mold interface where they are most desired for ensuring casting quality, but much less within the bulk of the mold where they are undesirable. This characteristic of cellulose offers an important opportunity for green sand foundries to diminish their hazardous air pollutant (HAP) emissions. 相似文献
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Cavitary pulmonary disease secondary to coccidioidomycosis occurs in endemic areas of the southwestern United States. Significant hemoptysis requiring pulmonary resection may develop in patients with cavitary lesions. In rare instances hemoptysis may be due to the development of a fungus ball within the cavity, and such mycetomas may contain spherule and mycelial forms of Coccidioides immitis. A patient with a documented coccidioidal cavity who had hemoptysis is described in this report. Chest radiograph revealed a fungus ball within a left lower lobe cavity. The patient underwent left lower lobectomy and recovered without complications. Examination of the resected left lower lobe disclosed a cavity containing a fungus ball comprised of mycelial and spherule forms of Coccidioides immitis. A review of the literature found three reports of biphasic growth of this condition within a coccidioidomycosis cavity and two additional cases of radiographically diagnosed coccidioidal mycetoma. Discussion of the potentially contagious nature, the medical and surgical management, and the prognosis of coccidioidal mycetoma form the basis of this report. 相似文献
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