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91.
Northrop Robert B. Woodruff Eileen A. 《IEEE transactions on bio-medical engineering》1986,(11):1010-1020
This paper describes the designs for two novel, nonlinear, discrete, drug injection controllers. The basis for these controllers is integral pulse frequency modulation (IPFM). An IPFM controller injects small boluses of a drug into a pharmacokinetic (PK) plant to achieve regulation of the plant output. Bolus injections are advantageous because they provide a precise knowledge of the times and the cumulative amount of drug injected, and they require a discrete-action pump suitable for digital control, miniaturization, and implantation. 相似文献
92.
介绍了重力式,衡重式挡土墙计算,设计CAD系统,该系统的应用,使土木工程中的挡土墙设计了多方案比较,科学优化,安全高效,计算,设计至出图可连续作业的自动化过程。 相似文献
93.
94.
Maomin Fan Eileen N. Duesler Jerzy F. Janik Robert T. Paine 《Journal of Inorganic and Organometallic Polymers and Materials》2007,17(2):423-437
The transamination reactions between Ti(NMe2)4 and 1,3,4,5,6-pentamethyl-2-aminoborazine, (Me)3N3(Me)2B3(NH2), and diphenylamine (Ph2NH) and between [Zr(NMe2)4]2 and 1,3,4,5,6-pentamethyl-2-aminoborazine, aniline (PhNH2) and diphenylamine have been studied and the molecular product species have been isolated, spectroscopically characterized
and single crystal X-ray structure analyses completed. The results of these studies have been used to interpret the outcome
of reactions of Ti(NMe2)4 and Zr(NMe2)4 with borazinylamine preceramic polymers that, upon pyrolysis, produce TiN/BN, ZrN/BN and ZrH0.6N/BN composite powders.
The transamination reactivity of a two-point poly(borazinylamine) oligomer having terminal –NH2 amino groups with Ti(NMe2)4 and Zr(NMe2)4 has been used to obtain metallated preceramic oligomers that, upon pyrolysis, give TiN/BN and ZrN/ZrH0.6N/BN nanocomposites. Model reactions of 1,3,4,5,6-pentamethyl-2-amino borazine, aniline and Ph2NH2 with Ti(NMe2)4 and Zr(NMe2)4 are also described as models for the formation of the metallated oligomers. Molecular structure determinations for the metal
amides are presented.
We dedicate this paper to Professor Christopher W. Allen in recognition of his distinguished career and his accomplishments
in inorganic ring and polymer chemistry. 相似文献
95.
Brian J. Boro Eileen N. Duesler Karen I. Goldberg Richard A. Kemp 《Inorganic chemistry communications》2008,11(12):1426-1429
The reaction of (PCP)i-PrPdCl and the commonly-used reductant K-Selectride® solution [K(sec-Bu3BH) in THF] does not yield a simple (PCP)i-PrPdH species, but rather an adduct of the Pd–H that contains bound K(sec-Bu3BH). This adduct has been characterized by X-ray crystallography and shown to be a centrosymmetric dimer in the solid state. The most unique feature of the structure is that the tri-coordinate K+ ion bonds only to the terminal palladium hydride and the two bridging boron hydrides. Despite being prepared in THF, no other donor ligands are bound to K+. This [H3K]+ bonding mode for K+ ions has not been previously reported. 相似文献
96.
In 2 experiments children in Grades 4–8 learned facts under different instructional conditions. Control Ss were given base sentences containing facts and were permitted to study them as they wished. In some conditions fact sentences were accompanied by elaborations (e.g., an explanation of why a stated animal lived in a stated locale). Ss in the elaborative interrogation conditions attempted to construct their own reasons for why the facts held true. Ss in the imagery conditions constructed internal imaginal representations for each fact (e.g., an image of a stated animal living in the stated locale). Elaborative interrogation was the only condition that significantly facilitated acquisition of facts in both experiments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
Cher Liang Cha Eng Fong Chor Hao Gong An Qing Zhang Lap Chan 《Semiconductor Manufacturing, IEEE Transactions on》2000,13(3):386-389
The breakdown time of flash memory oxide/nitride/oxide (ONO) layer tbd under positive constant current stressing has been found to be closely related to the cumulative extent of (over)etch of the tungsten silicide, control polysilicon, and ONO layers, i.e., Σ(ΛOE). An empirical first-order relation between tbd and Σ(ΛOE) has been derived to facilitate the plasma etch recipe optimization. This has led to a four-fold increase in the average tbd across a 200-mm wafer to 208 s. More importantly, the spread in tbd has been tightened to ~5%, which is down from ~54% 相似文献
98.
Wood Eileen; Willoughby Teena; Specht Jacqueline; Stern-Cavalcante Wilma; Child Carol 《Canadian Metallurgical Quarterly》2002,94(1):164
Early childhood educators (n=133) were assigned to 1 of 3 instructional conditions (direct, guided discovery, or no-exposure control) to assess the impact of computer workshops on their level of computer anxiety, computer knowledge, and comfort with computer technology. Groups were matched for computer experience and anxiety, early childhood education (ECE) experience, and ECE center. The direct and guided discovery groups attended a 3-hr hands-on workshop covering hardware, software, and Internet material. Immediately after the workshops, computer anxiety was lower and comfort with computer technology increased. Six months later, the control group had reduced computer anxiety, but the other groups maintained greater knowledge and comfort. Direct instruction reduced computer anxiety slightly but did not promote the acquisition of information of the guided condition. Overall, workshops provided gains that could translate into more effective and efficient computer use in the classroom. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
100.
Objective: This article presumes familiarity with the basics of multiple regression and correlation (MRC) methods and addresses recent controversies and emerging innovations. Areas of emphasis include linking analyses to theory-driven hypotheses, treatment of covariates in hierarchical regression models, recent debates about the testing of mediator and moderator hypotheses, and incorporating confidence intervals into reports of findings using MRC. Conclusions: Two important conceptual innovations (linking analyses closely to theory-derived hypotheses; focusing interpretations on effect sizes and confidence intervals rather than p values) can increase the scientific yield for researchers making use of MRC methods in rehabilitation psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献