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81.
杭州大学弱智儿童问题研究组 《浙江大学学报(理学版)》1987,14(3):362-370
为了能对弱智儿童智力缺损的程度作出较好的鉴别和帮助矫治起见,编制了一份适用于浙江省的儿童智力量表。本文讨论量表内容的选择和确定。 研究过程与方法:以两套不同内容的材料(共71题),先后分两次对31名小学一年级7岁儿童和28名弱智学校儿童(7—13岁)进行个别测试。根据测试结果的分析和比较,最后选定42题,编排为10个分测验,作为本量表的内容。它们是:1)图画填充;2)照管日常生活;3)实物排列;4)计算;5)图片归类;6)分辨能力;7)拼积木;8)数字背诵;9)划去图形;10)理解。 相似文献
82.
Food Allergens 总被引:1,自引:0,他引:1
83.
AOAC International methods committee guidelines for validation of qualitative and quantitative food microbiological official methods of analysis 总被引:1,自引:0,他引:1
Feldsine P Abeyta C Andrews WH;AOAC International Methods Committee 《Journal of AOAC International》2002,85(5):1187-1200
Responding to a need for a guide for conducting Official Method validation studies of microbiological methods, AOAC utilized the experience of three microbiologists who have been active in the field of method validation. In collaboration, a document was prepared which covered the following areas: terms and their definitions associated with the Official Methods program (e.g., reference methods, alternative methods, and ruggedness testing), protocols and validation requirements for qualitative methods versus those for quantitative methods, the concept of the precollaborative study, ruggedness testing, tests for significant differences, performance indicators, and the approval process. After its preparation, this document was reviewed by the members of the Methods Committee on Microbiology and Extraneous Materials and by members of the Official Methods Board. Herein is presented the approved version of that document. 相似文献
84.
The Buenos Aires Cyclic Homology Group 《K-Theory》1991,5(1):51-69
We compute the cyclic homology of A = k[X]/X
n for an arbitrary commutative ring k, and we apply this result to compute the cyclic homology of k[X]/f, when k is a field and f is an arbitrary polynomial.This work was presented at the IX-ELAM, Santigo de Chile, July 1988, and was partially supported by CONICET.The following pepole participated in this research: Jorge A. Guccione, juan José guccione, Maria Julia Redondo, Andrea Solotar, and Orlando E. Villamayor. 相似文献
85.
Krishnan A Liu YH Cha P Woodward R Allara D Vogler EA;Hematology at Biomaterial Interfaces Research Group 《Colloids and surfaces. B, Biointerfaces》2005,43(2):95-98
A systematic comparison of Wilhelmy-balance tensiometry (WBT), tilting-plate goniometry (TPG) and captive-drop goniometry (CDG), using a variety of silane-treated glass surfaces of variable wetting characteristics is reported. WBT was assumed to be the benchmark of comparison (gold standard). Advancing angles measured by TPG and CDG were in statistical agreement with corresponding WBT measurements. In contrast, receding angles from both goniometric techniques were systematically higher than WBT. 相似文献
86.
Lewis JK Rudzinsky J Rajan S Stein PJ Vandiver A;KauaiEx Group 《The Journal of the Acoustical Society of America》2005,117(6):3539-3554
A tomographic scheme is presented that ingests ocean acoustic measurements into an ocean model using data from bottom-mounted hydrophones. The short distances between source-receiver pairs (1-10 km) means arrival times at frequencies of 8-11 kHz are readily detectable and often distinguishable. The influence of ocean surface motion causes considerable variability in acoustic travel times. Techniques are presented for measuring travel times and removing the variability due to surface waves. An assimilation technique is investigated that uses differences in measured and modeled acoustic travel times to impose corrections on the oceanographic model. Equations relating travel time differences to oceanographic variables are derived, and techniques are presented for estimating the acoustic and ocean model error covariance matrices. One test case using a single source-receiver pair shows that the tomographic information can have an impact on constraining the solution of the ocean circulation model but can also introduce biases in the predictions. A second test case utilizes knowledge of a bias in a model-predicted variable to limit grid cells that are impacted by the tomographic data. In this case, using the tomographic data results in significant improvements in the model predictions without introducing any biases. 相似文献
87.
88.
ZHU ChunLei WANG Qing ZHAO YaJun WANG YingMin QIANG JianBing & DONG Chuang Key Lab of Materials Modification School of Materials Science Engineering Dalian University of Technology Dalian China International Center for Materials Physics Chinese Academy of Sciences Shenyang 《中国科学:物理学 力学 天文学(英文版)》2010,(3)
The glass-forming ability and properties of Ni-based Ni-Fe-B-Si-Ta bulk metallic glasses are explored in this work. The alloy compositions are determined by using a combination of the cluster line approach, the multi-alloying strategy and the substitutions of similar elements. Bulk metallic glasses with diameters of 3 mm take shape at compositions formulated under the clus- ter-plus-glue-atom model [M9B]B~[(Ni1-xFex)7.71(Si0.66Ta0.34)1.29B]B0.94=(Ni1-xFex)70.5B17.7Si7.8Ta4, x=0.35–0.45, where the bracketed part is the cluster and the unbracketed part is the glue atoms. These alloys exhibit good magnetic properties. The maximum Is is found in the (Ni0.55Fe0.45)70.5B17.7Si7.8Ta4 alloy which reaches 0.51 T, with its Hc as low as 8.5 A/m. Interestingly, these alloys display dual glass transitions at (Ni0.65Fe0.35)70.5B17.7Si7.8Ta4, (Ni0.60Fe0.4)70.5B17.7Si7.8Ta4 and (Ni0.55Fe0.45)70.5B17.7- Si7.8Ta4 as unveiled by Temperature-Modulated Differential Scanning Calorimetry. 相似文献
89.
The aim of this work was to determine the effect of formulation of alginate beads on their mechani-cal behavior and stiffness when compressed at high speed. The alginate beads were formulated using different types and concentrations of alginate and gelling cations and were produced using an extrusion-dripping method. Single wet beads were compressed at a speed of 40 mm/min,and their elastic limits were investigated,and the corresponding force versus displacement data were obtained. The Young's moduli of the... 相似文献
90.
建立快速溶解硅铁及其合金的试验方法,并利用电感耦合等离子体发射光谱仪分析检测硅铁及其合金中微量元素及痕量元素,证明了快速溶解法的可行性.结果显示,方法的精密度及检测仪器重复性测量不确定度的结果均符合国家标准规定的允许偏差范围,说明快速溶解法具有一定推广价值和应用前景. 相似文献