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31.
柿竹园多金属矿黑、白钨矿的比例约为3:7,根据黑钨矿的矿石性质,在磨矿回路中加和重选早收已角度的单体钨矿物,有利于减轻黑钨矿过粉碎和减少黑钨细泥。小型试验、扩大试验和工业试验,在磨矿回路中获得11.82% ̄16.97%的黑钨回收率,使全流程合格钨精矿的总回收率达81.89% ̄86.23%。 相似文献
32.
Richard E. Lyon Natallia Safronava James G. Quintiere Stanislav I. Stoliarov Richard N. Walters Sean Crowley 《火与材料》2014,38(2):264-278
Five material properties commonly used to describe the fire behavior of solids were evaluated as sole explanatory variables for four small‐scale fire tests with pass/fail outcomes by using a physically based probabilistic (phlogistic) burning model. The phlogistic model describes the likelihood of passing vertical Bunsen burner tests and a regulatory heat release rate test reasonably well over a wide range of material properties, as deduced from the correlation coefficient and mean deviation of the predicted and measured values. Of the thermal, combustion, and fire properties examined, the best predictors of the likelihood of passing the fire tests of this study were the heat of combustion of the sample, the heat release capacity, and the heat release parameter. The relative merits and drawbacks of qualitative (threshold) and quantitative (probabilistic) approaches to predicting fire test results using thermal and combustion properties are discussed. Published 2013. This article is a U.S. Government work and is in the public domain in the USA. 相似文献
33.
Robert J. Walters Geoffrey P. Summers Scott R. Messenger Edward A. Burke 《Progress in Photovoltaics: Research and Applications》1996,4(2):111-116
The measured degradation of epitaxial shallow homojunction n+p InP solar cells under 1-MeV electron irradiation is correlated with that measured under 3-MeV proton irradiation based on ‘displacement damage dose’. The measured data are analyzed as a function of displacement damage dose from which an electron-to-proton dose equivalency ratio is determined which enables the electron and proton degradation data to be described by a single degradation curve. It is discussed how this single curve can be used to predict the cell degradation under irradiation by any particle energy. The degradation curve is used to compare the radiation response of InP and GaAs/Ge cells on an absolute damage energy scale. The comparison shows InP to be inherently more resistant to displacement damage deposition than the GaAs/Ge. 相似文献
34.
35.
The chemistry between NO
x
species adsorbed on La2O3 and CH4 was probed by temperature‐programmed reaction (TPR) as well as in situ DRIFTS. During NO reduction by CH4 in the presence of O2, NO
3
-
does not appear to activate CH4, thus either an adsorbed O species or an NO
2
-
species is more likely to activate CH4. In the absence of O2, a different reaction pathway occurs and NO- or (N2O2)2- species adsorbed on oxygen vacancy sites seem to be active intermediates, and during NO reduction with CH4 unidentate NO
3
-
, which desorbs at high temperature, behaves as a spectator species and is not directly involved in the catalytic sequence.
Because reaction products such as CO2 or H2O as well as adsorbed oxygen cannot be effectively removed from the surface at lower temperatures, steady‐state catalytic
reactions can only be achieved at temperatures above 800 K, even though formation of N2 and N2O from NO was observed at much lower temperature during the TPR experiments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
36.
Brucker RM Baylor CM Walters RL Lauer A Harris RN Minbiole KP 《Journal of chemical ecology》2008,34(1):39-43
Beneficial bacteria that live on salamander skins have the ability to inhibit pathogenic fungi. Our study aimed to identify
the specific chemical agent(s) of this process and asked if any of the antifungal compounds known to operate in analogous
plant–bacteria–fungi systems were present. Crude extracts of bacteria isolated from salamander skin were exposed to HPLC,
UV-Vis, GC-MS, and HR-MS analyses. These investigations show that 2,4-diacetylphloroglucinol is produced by the bacteria isolate
Lysobacter gummosus (AB161361), which was found on the red-backed salamander, Plethodon cinereus. Furthermore, exposure of the amphibian fungal pathogen, Batrachochytrium dendrobatidis (isolate JEL 215), to different concentrations of 2,4-diacetylphloroglucinol resulted in an IC50 value of 8.73 μM, comparable to crude extract concentrations. This study is the first to show that an epibiotic bacterium
on an amphibian species produces a chemical that inhibits pathogenic fungi. 相似文献
37.
38.
M J Arambel R D Wiedmeier D H Clark R C Lamb R L Boman J L Walters 《Journal of dairy science》1988,71(1):159-163
Forty-eight lactating Holstein cows were fed a total mixed ration of 57% concentrate and 43% forage (dry basis) for 12 wk postpartum. Treatments consisted of 1) no added buffers, 2) .4% MgO, 3) .8% NaHCO3, and 4) .8% NaHCO3 plus .4% MgO of the total ration DM. Body weight, DM intake, and milk yield and composition were unaffected by treatment. Gross efficiency of milk production was decreased by the addition of NaHCO3 or MgO. Buffer supplementation had no effect on ruminal volatile fatty acid concentration or blood chemistries. 相似文献
39.
40.
Factor-analytic research is common in the study of constructs and measures in psychological assessment. Latent factors can represent traits as continuous underlying dimensions or as discrete categories. When examining the distributions of estimated scores on latent factors, one would expect unimodal distributions for dimensional data and bimodal or multimodal distributions for categorical data. Unfortunately, identifying modes is subjective, and the operationalization of counting local maxima has not performed very well. Rather than locating and counting modes, the authors propose performing parallel analyses of categorical and dimensional comparison data and calculating an index of the relative fit of these competing structural models. In an extensive Monte Carlo study, the authors replicated prior results for mode counting and found that trimming distributions' tails helped. However, parallel analyses of comparison data achieved much greater accuracy, improved base rate estimation, and afforded consistency checks with other taxometric procedures. Two additional studies apply this approach to empirical data either known to be categorical or presumed to be dimensional. Each study supports this new method for factor-analytic research on the latent structure of constructs and measures in psychological assessment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献