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排序方式: 共有188条查询结果,搜索用时 15 毫秒
181.
This paper reports the first application of the multicriteria decision making methods, PROMETHEE and GAIA, to indoor and outdoor air quality data. Fourteen residential houses in a suburb of Brisbane, Australia were investigated for 21 air quality-influencing criteria, which included the characteristics of the houses as well as the concentrations of volatile organic compounds, fungi, bacteria, submicrometer, and supermicrometer particles in their indoor and outdoor air samples. Ranking information necessary to select one house in preference to all others and to assess the parameters influencing the differentiation of the houses was found with the aid of PROMETHEE and GAIA. There was no correlation between the rank order of each house and the health complaints of its occupants. Patterns in GAIA plots show that indoor air quality in these houses is strongly dependent on the characteristics of the houses (construction material, distance of the house from a major road, and the presence of an in-built garage). Marked similarities were observed in the patterns obtained when GAIA and factor analysis were applied to the data. This underscores the potential of PROMETHEE and GAIA to provide information that can assist source apportionment and elucidation of effective remedial measures for indoor air pollution.  相似文献   
182.
183.
Five different hydrochlorothiazide (50mg. per capsule) capsule formulations were prepared with one of the following diluents: corn starch, dibasic calcium phosphate, lactose, microcrystalllne cellulose, or sodium carboxymethyl starch. A comparative dissolution study was conducted using the USP procedure. Significant differences (p = 0.05) were found among the formulations relative to in vitro dissolution rates over a two-hour sampling period. The formulations prepared with lactose consistently ranked near the top (Newman-Keuls multiple range test) while the formulation prepared with sodium carboxymethyl starch ranked last at each sampling time except 3 min.  相似文献   
184.
An increased incidence of colorectal cancer has been observed in breast and breast-ovarian cancer syndrome families, including those of Ashkenazi origin. Recently, a germ-line missense mutation in the APC gene, I1307K, was identified that may indirectly cause colorectal cancer in Ashkenazi Jews. To determine whether the excess of colon cancer in some breast-ovarian cancer families is related to the I1307K mutation, we evaluated 264 Ashkenazi Jews from 158 families. Most of these individuals had either a personal or a family history of breast and/or ovarian cancer, and 19.3% (51 of 264) carried one of the recurrent BRCA1 (185delAG or 5382 insC) or BRCA2 (6174delT) mutations. We detected the APC I1307K mutation in 7% (11 of 158) of the Ashkenazi Jewish families and in 4.5% (12 of 264) of the individuals participating in these studies. Of the families studied, 26.6% (42 of 158) had at least one case of colorectal cancer in a first-, second-, or third-degree relative of the proband. Significantly, of the 12 individuals who possessed the I1307K mutation, none was diagnosed with colorectal cancer and none had a known first-, second-, or third-degree relative diagnosed with colon cancer. The results suggest that factors other than the I1307K mutation contribute to the increased incidence of colon cancer in Ashkenazi breast-ovarian cancer families. Our results emphasize that only a subset of Ashkenazi Jewish individuals with a family history of colorectal cancer should be viewed as candidates for genetic susceptibility testing for the I1307K APC mutation.  相似文献   
185.
On- and off-responses to a prolonged optical stimulus (up to 1000 ms) were studied in the cat sensomotor cortex. Similarity of the minimum time of stimulation resulting in the off-response with the cycle of the functional restoration after a single flash was observed. It is suggested that IPSP arising in the cortical neurons form a basis of these time intervals. The influence of stimuli of other modalities (cutaneous) on the off-responses is shown. This influence was observed in the case when the cortical neuron produced an impulse discharge to the cutaneous stimulus.  相似文献   
186.
Polymer Bulletin - The effect of Kankara zeolite-Y-based catalyst on some physical properties of liquid fuel obtained from the pyrolysis of mixed waste plastics has been investigated. Combination...  相似文献   
187.
Comparative assessment of III?CV heterostructure and silicon underlap DG-MOSFETs, is done using 2D Sentaurus TCAD simulation. III?CV heterostructure device has narrow-band In0.53Ga0.47As and wide-band InP layers for body, and high-K gate dielectric. Density gradient model is used for simulation and interface traps are considered. Benchmarking of simulation results show that III?CV device provides higher on current, lesser delay, lower energy-delay product and lower DIBL than silicon device. However III?CV device has higher SS and lower I on/I off than silicon device. The results indicate that there is a need to optimize the I on/I off, SS and DIBL values for specific circuits.  相似文献   
188.
We present a two-dimensional electron gas(2DEG) charge-control mobility variation based drain current model for sheet carrier density in the channel.The model was developed for the AlInGaN/AlN/GaN highelectron -mobility transistor.The sheet carrier density model used here accounts for the independence between the Fermi levels Ef and ns along with mobility for various Al and In molefractions.This physics based ns model fully depends upon the variation of Ef,u0,the first subband E0,the second subband E\,and ns.We present a physics based analytical drain current model using ns with the minimum set of parameters.The analytical results obtained are compared with the experimental results for four samples with various molefraction and barrier thickness.A good agreement between the results is obtained,thus validating the model.  相似文献   
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