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11.
G Chessa Ricotti R Cutrì A De Bernardi M Funis S Frediani 《Canadian Metallurgical Quarterly》1995,17(3):271-273
The authors describe 5 cases, 3 boys and 2 girls, with idiopathic growth hormone deficiency in prepubertal age, treated with human growth hormone. In four of five cases the response to treatment with GH was relevant. Only in one case (F1) the response was negative. The results of this study confirm that rhGH is a safe and effective therapy in children with GHD. 相似文献
12.
台北101层国际金融中心之结构施工技术与其设计考量概述 总被引:1,自引:0,他引:1
本文旨在简要说明目前正在施工中之超高层大楼—台北国际金融中心之结构系统、钢结构工程、钢筋混凝土工程基础与深开挖工程等特殊施工技术,并佐以相关之设计考量与施工规划概要,以供工程界做参考。 相似文献
13.
14.
Nicholas Biery Marc De Graef Jack Beuth Rafel Raban Andrew Elliott Tresa M. Pollock Curt Austin 《Metallurgical and Materials Transactions A》2002,33(10):3127-3136
Tensile experiments have been performed on specimens of four different investment-cast TiAl-based alloys with variations in
casting conditions. The average ductilities obtained in these experiments vary between approximately 0.8 to 2.0 pct plastic
strain to failure in tension. By using the three-parameter form of the Weibull relation, with the 0.2 pct offset yield strength
as the minimum failure strength, the resulting variability in the data can be quantified and is found to be similar for those
alloys with similar microstructural scale (grain size). Large variations in lamellar volume fraction, segregation, and phase
distribution have a minor influence on property variability, compared to changes in the scale of the grain structure caused
by either variations in cooling rate during casting or the addition of grain refiners. 相似文献
15.
Summary The influence of draw ratio on macroscopic and crystallographic density of polyethylene with different initial morphologies, has been investigated by solid-state extrusion. An initial drop followed by an increase in macroscopic density as a function of draw ratio has been observed. Since precision X-ray measurements of unit cell parameters showed no variation of crystallographic density, it was concluded that plastic deformation of polyethylene upon drawing proceeds with a decrease of the degree of crystallinity. This was confirmed by differential scanning calorimetry. 相似文献
16.
A photochromic nanocomposite based on Keggin structure phosphomolybdic acid (PMoA) well dispersed in polyethyleneglycol (PEG) was fabricated. TEM image showed that PMoA nanoparticles with narrow size distribution were finely dispersed in polymer matrix. FT-IR results showed that the Keggin geometry of polyoxometalates was still preserved inside the composites and strong coulombic interaction was built between PMoA and polymer matrix. Under UV irradiation, the film was reduced photochemically to yield a blue species, which was in accordance with a charge-transfer mechanism. 相似文献
17.
O Bernard B Chachuat A Hélias B Le Dantec B Sialve J-P Steyer L Lardon P Neveu S Lambert J Gallop M Dixon P Ratini A Quintabà S Frattesi J M Lema E Roca G Ruiz J Rodriguez A Franco P Vanrolleghem U Zaher D J W De Pauw K De Neve K Lievens D Dochaine O Schoefs H Fibrianto R Farina V Alcaraz Gonzalez V Gonzalez Alvarez P Lemaire J A Martinez F Esandi O Duclaud J F Lavigne 《Water science and technology》2005,52(1-2):457-464
The TELEMAC project brings new methodologies from the Information and Science Technologies field to the world of water treatment. TELEMAC offers an advanced remote management system which adapts to most of the anaerobic wastewater treatment plants that do not benefit from a local expert in wastewater treatment. The TELEMAC system takes advantage of new sensors to better monitor the process dynamics and to run automatic controllers that stabilise the treatment plant, meet the depollution requirements and provide a biogas quality suitable for cogeneration. If the automatic system detects a failure which cannot be solved automatically or locally by a technician, then an expert from the TELEMAC Control Centre is contacted via the internet and manages the problem. 相似文献
18.
Magnus Rnning Florian Huber Hilde Meland Hilde Venvik De Chen Anders Holmen 《Catalysis Today》2005,100(3-4):249-254
In order to investigate the effect of cerium oxide on Cu–Zn-based mixed-oxide catalysts four catalyst samples were characterized by means of XRD, in situ XANES and thermogravimetric analysis. The activity of the catalyst samples was tested for the forward water–gas shift reaction. Cerium oxide was found to increase the crystallinity of the ZnO phase indicating a segregation of the Cu and ZnO phases. The TOF of the water–gas shift reaction based on chemisorption data was found to be independent of composition and preparation conditions of the four catalyst samples. In contrast, the catalyst stability depends on composition and preparation conditions. Cerium oxide impregnated before calcination of the hydrotalcite-based Cu–Zn precursors leads to a more stable water–gas shift catalyst. 相似文献
19.
On sorting triangles in a delaunay tessellation 总被引:1,自引:0,他引:1
In a two-dimensional Delaunay-triangulated domain, there exists a partial ordering of the triangles (with respect to a vertex) that is consistent with the two-dimensional visibility of the triangles from that vertex. An equivalent statement is that a polygon that is star-shaped with respect to a given vertex can be extended, one triangle at a time, until it includes the entire domain. Arbitrary planar triangulations do not possess this useful property which allows incremental processing of the triangles.This work was partially supported by the National Science Foundation's US-Italy Collaborative Research Program under Grant INT-8714578 and Information, Robotics, and Intelligent Research Grant IRI-8704781. 相似文献
20.
Xue‐Bing Zhao Lei Wang De‐Hua Liu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(6):950-956
Previous work has shown that the enzymatic hydrolysis of sugarcane bagasse could be greatly enhanced by peracetic acid (PAA) pretreatment. There are several factors affecting the enzymatic digestibility of the biomass, including lignin and hemicelluloses content, cellulose crystallinity, acetyl group content, accessible surface area and so on. The objective of this work is to analyze the mechanism of the enhancement of enzymatic digestibility caused by PAA pretreatment. Delignification resulted in an increase of the surface area and reduction of the irreversible absorption of cellulase, which helped to increase the enzymatic digestibility. The Fourier transform infrared (FTIR) spectrum showed that the absorption peaks of aromatic skeletal vibrations were weakened or disappeared after PAA pretreatment. However, the infrared crystallization index (N.O'KI) was increased. X‐ray diffraction (XRD) analysis indicated that the crystallinity of PAA‐treated samples was increased owing to the partial removal of amorphous lignin and hemicelluloses and probable physical change of cellulose. The effect of acetyl group content on enzymatic digestibility is negligible compared with the degree of delignification and crystallinity. The results indicate that enhancement of enzymatic digestibility of sugarcane bagasse by PAA pretreatment is achieved mainly by delignification and an increase in the surface area and exposure of cellulose fibers. Copyright © 2008 Society of Chemical Industry 相似文献