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991.
研究功能梯度泡沫填充管(FGFTs)在落锤冲击载荷作用下的变形行为和耐撞性.采用液态工艺制备的闭孔泡沫铝、A356合金泡沫和锌泡沫作为轴向梯度填料,用于制备不同构造的单层和多层结构.结果表明,多层泡沫填充管的变形由低强度部位开始,然后通过应力的逐渐增加在高强度部位中扩展.使用更多的A356合金和泡沫铝层可为梯度结构提供... 相似文献
992.
以二茂铁为催化剂前驱体,C2H2为碳源,在NH3和N2气氛中在Al2O3多孔基体上化学气相沉积制备出了一致取向的碳纳米管阵列.采用拉曼散射、扫描电子显微镜、高分辨电子显微镜、X射线衍射和元素分析等技术对产物进行表征.实验结果表明,以NH3为载气时,所制备的碳纳米管为竹节形结构,并且有一定量的N掺杂在其中,其质量含量大约在3.46%,碳纳米管的石墨层间距在0.384 nm左右,实验产物中有Fe3C和Fe2N或Fe3N的生成,NH3在催化剂表面的吸附导致催化剂的表面性质的改变以及N的掺杂使生成的碳纳米管结构有一些缺陷,石墨化程度有所降低.碳纳米管的管径随着反应温度的增加而增大. 相似文献
993.
This work is part of a multi-phase project which aims to develop a sound methodology for rock fragmentation in underground mines using expansive cement. More specifically, it is the first phase of the project which focuses on laboratory tests to investigate the mechanical performance of expansive cement, also known as soundless chemical demolition agents(SCDA). This paper reports the results of laboratory tests conducted on instrumented thick-walled cylinders filled with expansive cement. Expans... 相似文献
994.
Wei Wang Tao Zhang Jan Nouta Peter A. van Veelen Noortje de Haan Theo M. de Reijke Manfred Wuhrer Guinevere S.M. Lageveen-Kammeijer 《工程(英文)》2023,(7):119-131
Ketodeoxynononic acid(Kdn) is a rather uncommon class of sialic acid in mammals. However, associations have been found between elevated concentrations of free or conjugated Kdn in relation to human cancer progression. Hitherto, there has been a lack of conclusive evidence that Kdn occurs on(specific)human glycoproteins(conjugated Kdn). Here, we report for the first time that Kdn is expressed on prostate-specific antigen(PSA) N-linked glycans derived from human seminal plasma and urine.Interestin... 相似文献
995.
The present study is concerned with the computational fluid dynamics(CFD) simulation of turbulent dispersion of immiscible liquids, namely, water–silicone oil and water–benzene through Kenics static mixers using the Eulerian–Eulerian and Eulerian–Lagrangian approaches of the ANSYS Fluent 16.0 software. To study the droplet size distribution(DSD), the Eulerian formulation incorporating a population balance model(PBM) was employed. For the Eulerian–Lagrangian approach, a discrete phase model(DPM) in conjunction with the Eulerian approach for continuous phase simulation was used to predict the residence time distribution(RTD) of droplets.In both approaches, a shear stress transport(SST) k-ω turbulence model was used. For validation purposes, the simulated results were compared with the experimental data and theoretical values for the Fanning friction factor, Sauter mean diameter and the mean residence time. The reliability of the computational model was further assessed by comparing the results with the available empirical correlations for Fanning friction factor and Sauter mean diameter. In addition, the influence of important geometrical and operational parameters, including the number of mixing elements and Weber number, was studied. It was found that the proposed models are capable of predicting the performance of the Kenics static mixer reasonably well. 相似文献
996.
Suying Xu Adam C. Sedgwick Souad A. Elfeky Wenbo Chen Ashley S. Jones George T. Williams A. Toby A. Jenkins Steven D. Bull John S. Fossey Tony D. James 《Frontiers of Chemical Science and Engineering》2020,14(1):112
A boronic acid-based anthracene fluorescent probe was functionalised with an acrylamide unit to incorporate into a hydrogel system for monosaccharide detection. In solution, the fluorescent probe displayed a strong fluorescence turn-on response upon exposure to fructose, and an expected trend in apparent binding constants, as judged by a fluorescence response where D-fructose>D-galactose>D-mannose>D-glucose. The hydrogel incorporating the boronic acid monomer demonstrated the ability to detect monosaccharides by fluorescence with the same overall trend as the monomer in solution with the addition of D-fructose resulting in a 10-fold enhancement (≤0.25 mol/L). 相似文献
997.
介绍了用DSE异收缩纱制织atmofil花色织物时的工艺条件,后整理对织物外观和性能的影响,以及该类织物的应用范围. 相似文献
998.
Van de Wiele公司推出了一种具有革命性意义的双面起绒新工艺:使用3剑杆,采用700 d/m的筘齿密度和8种绒面颜色设计的工艺条件织制出织物组织为1/2 V固结的起绒地毯. 相似文献
999.
Cornelius B. Bavoh Bhajan Lal Omar Nashed Muhammad S. Khan Lau K. Keong Mohd. Azmi Bustam 《中国化学工程学报》2016,24(11):1619-1624
Recently ionic liquids(ILs) are introduced as novel dual function gas hydrate inhibitors. However, no desired gas hydrate inhibition has been reported due to poor IL selection and/or tuning method. Trial error as well as selection based on existing literature are the methods currently employed for selecting and/or tuning ILs. These methods are probabilistic, time consuming, expensive and may not result in selecting high performance ILs for gas hydrate mitigation. In this work, COSMO-RS is considered as a prescreening tool of ILs for gas hydrate mitigation by predicting the hydrogen bonding energies(E_(HB)) of studied IL inhibitors and comparing the predicted E_(HB) to the depression temperature(?) and induction time. Results show that, predicted EHBand chain length of ILs strongly relate and significantly affect the gas hydrate inhibition depression temperature but correlate moderately(R = 0.70) with average induction time in literature. It is deduced from the results that, ? increases with increasing IL EHBand/or decreases with increasing chain length. However, the cation–anion pairing of ILs also affects IL gas hydrate inhibition performance. Furthermore, a visual and better understanding of IL/water behavior for gas hydrate inhibition in terms of hydrogen bond donor and acceptor interaction analysis is also presented by determining the sigma profile and sigma potential of studied IL cations and anions used for gas hydrate mitigation for easy IL selection. 相似文献
1000.
<正> 在明胶中有两类照相活性的化合物,都含二价硫。它们一种是硫代硫酸盐离子,是普通增感剂;另一种是蛋白硫,可能是胱氨酸的残余,作为一种增感剂。其他亚硫酸化合物,例如连三硫酸盐及连四硫酸盐,也可能存在于明胶中,但未经化学转变,它们几乎不表现任何照相活性。明胶中亚硫酸化合物的来源为胱氨酸,例如生产纯胶的骨素中存在少量胱氨酸。 相似文献