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101.
P. Podhájecký B. Klápště P. Novák J. Mrha R. Moshtev V. Manev A. Nassalevska 《Journal of power sources》1985,14(4):269-275
A dozen CuO samples prepared under various conditions and from different starting materials were evaluated as cathode materials for a primary Li/CuO cell. The “thin electrode” method was used for rapid evaluation of the samples. Both coulombic efficiency and discharge voltage depend considerably on the method of synthesis. No correlation was found between the specific surface area and the resistivity of the samples on the one hand and the cathode performance on the other. Best results were obtained from CuO prepared by the oxidation of Cu2O under controlled temperature and time of oxidation. 相似文献
102.
103.
V. Recarte R. B. Pérez-Sáez J. San Juan E. H. Bocanegra M. L. Nó 《Metallurgical and Materials Transactions A》2002,33(8):2581-2591
The martensitic transformation temperatures and the types of martensitic phases have been determined in a wide concentration
range of technological interest for Cu-Al-Ni shape-memory alloys (SMAs) A stability diagram of martensitic phases as a function
of alloy concentration has been determined. It is found that when the aluminum content increases, the transformation changes
from β
3 ⇒ β′3 to β
3 ⇒ γ′3, with an intermediate concentration range where both martensites coexist due to a β
3 ⇒ γ′3+β′3 transformation. On the other hand, an increase of nickel content stabilizes the martensite β′3, changing from a mixed β
3 ⇒ γ′3 + β′3 to a single β
3 ⇒ β′3 transformation. Furthermore, linear relationships between M
s
and Al and Ni concentrations have been obtained for all types of martensitic phases. 相似文献
104.
105.
P Sánchez García 《Canadian Metallurgical Quarterly》1997,114(1):157-63; discussion 164-7
106.
N Benito A Nú?ez M de Górgolas J Esteban T Calabuig MC Rivas ML Fernández Guerrero 《Canadian Metallurgical Quarterly》1997,157(14):1577-1580
BACKGROUND: Fever is commonly observed in patients with human immunodeficiency virus (HIV) disease and frequently eludes diagnosis. The role of bone marrow biopsy in the diagnosis of fever of unknown origin in patients infected with HIV remains controversial. PATIENTS AND METHODS: One hundred twenty-three consecutive patients with 137 episodes of fever lasting 10 or more days without diagnosis after 1 week of hospitalization were evaluated by bone marrow biopsy. RESULTS: Overall, a specific diagnosis was achieved in 52 episodes by means of culture and histopathological examination (diagnostic yield, 37.9%). Three types of disease were found: mycobacterial infections (n = 36, 69% of documented episodes), including 18 patients with disseminated tuberculosis and 14 with Mycobacterium avium-intracellulare complex infections; non-Hodgkin lymphomas (n = 12, 23%); and visceral leishmaniasis (n = 4, 8%). Although bone marrow cultures were more sensitive than microscopic examination with special stains for the diagnosis of mycobacterial infections, the pathological examination of bone marrow led to a more rapid diagnosis of disease. In addition, the histopathological examination of bone marrow alone led to the diagnosis of a specific condition in 43 episodes (31.3% of all episodes). CONCLUSIONS: Bone marrow biopsy is a useful procedure for the diagnosis of fever in patients with advanced HIV disease, particularly in areas where tuberculosis and leishmaniasis are prevalent. Involvement of the marrow may be the first indication of the existence of extranodal non-Hodgkin lymphoma. For Mycobacterium avium-intracellulare complex infection, blood cultures were more sensitive than bone marrow biopsy. 相似文献
107.
In Costa Rica the mollusk Anadara tuberculosa represents a risk for human health due to the contamination of the growing waters and the fact that its is consumed raw. The families depending on the income obtained through commercialization of these animals have a low education and economic status. Therefore, it is of great importance to develop and evaluate simple methods of depuration that could be easily used by these families to make these mollusks safe for consumption. Bottles containing 11 of saline solution (25g/l) were prepared in duplicates to test the bactericidal effect of acetic acid. The solution in each bottle was adjusted to ph 4.5, 5.0 or 5.5 or held at ph of 7.0 or 8.0 for the controls. The solution in each bottle was then inoculated with approximately 1 X 104 cfu/ml of coliforms. Counts of coliforms were determined for each bottle 0, 1, 2, 4 and 8 hours after inoculation. For the depuration studies, specimens with diameters ranging from 4.0 to 4.5 cm were collected from a harvester at the estuary of Puntarenas, Gulf of Nicoya. Fifty specimens each were depurated in separate tanks containing 25 1 of oxygenated saline solution adjusted with acetic acid to an initial ph of 4.5 (treatment) or non adjusted ph of 8.0 (control). Counts of Enterobacteriaceae were determined, in duplicates, every 12 hr for 48 hr. An additional fifty animals were depurated using the defined method and tested to determine if they met international standards of microbiological quality for aerobic plate count, Enterobacteriaceae count, Escherichia coli count and presence of Salmonella. A sensory evaluation using a triangle test was performed to compare a typical dish prepared with depurated or non-depurated animals. A significant coliform reduction was determined in a saline solution (25 g/l) at a pH range of 4.5 to 5.5. This reduction, during 8 hr, was higher in the acid treatments compared to the controls. During depuration, the elimination of Enterobacteriaceae bacteria was faster when acetic was used (initial ph = 4.5) than when it was not. This elimination was more important the first 24 hr, time defined as adequate for the application of the method. The method has the advantage of transforming the bivalve in a product that is safe for human consumption, since it guarantees that the international standards of microbiological quality, for raw and depurated mollusks, are reached. On the other hand, the sensory qualities of a typical dish prepared with depurated animals are not affected by the method, which can be easily implemented and applied by the people that work in the extraction of this mollusk. 相似文献
108.
BACKGROUND: It is not clear if old age is a risk factor for adverse drug reactions. AIM: To study the incidence of adverse drug reactions and the effect of age in patients admitted to an Internal Medicine Service in an university hospital. PATIENTS AND METHODS: Two hundred one patients, hospitalized at the Clinical Hospital of the Catholic University, were studied. These patients were followed using a prospective pharmacological surveillance method. For statistical purposes, patients aged 65 years old or older were compared with those younger than 65 years old. RESULTS: Patients over 65 years old had a 33% incidence of adverse drug reactions, mainly involving cardiovascular system and provoking metabolic disturbances. Younger subjects had a 24% incidence of adverse drug reactions, mainly involving the gastrointestinal system and the skin. Sixteen percent of adverse drug reactions were classified as severe and there was a direct relationship between its frequency and the number of drugs prescribed, the hospitalization length and the presence of renal failure. Younger patients with adverse drug reactions had lower serum albumin levels than those without adverse reactions. This relationship was not observed in older patients. CONCLUSIONS: The frequency of adverse drug reactions in hospitalized patients, is related to the number of drugs prescribed and the length of hospitalization. 相似文献
109.
The Vesilind settling velocity function forms the basis of flux theory used both in state point analysis (for design and capacity rating) and one-dimensional dynamic models (for dynamic process modelling). This paper proposes new methods to address known shortcomings of these methods, based on an extensive set of batch settling tests conducted at different scales. The experimental method to determine the Vesilind parameters from a series of bench scale settling tests is reviewed. It is confirmed that settling cylinders must be slowly stirred in order to represent settling performance of full scale plants for the whole range of solids concentrations. Two new methods to extract the Vesilind parameters from settling test series are proposed and tested against the traditional manual method. Finally, the same data set is used to propose an extension to one-dimensional (1-D) dynamic settler models to account for compression settling. Using the modified empirical function, the model is able to describe the batch settling interface independently of the number of layers. 相似文献
110.
A new analytical method has been developed for the determination of the reactive lysine content of soya bean protein. The method is based on the reaction of the free basic groups of the protein with 1-phenylazo-2 naphthol-6,8 disulphonic acid. With regard to the stoichiometry of the procedure, it has been proved, contrary to earlier reports, that the basic amino acids, histidine, arginine and lysine, each combine with one mole of the dye. After acylation with propionic anhydride lysine alone loses its dye reactivity. The usefulness of the proposed method has been demonstrated by the determination of the reactive lysine content of several untreated, heat-treated and acid-treated soya bean samples. The results show that heat damage of about 5% in reactive lysine content can be measured in 1·5 h with good reproducibility. 相似文献