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101.
Peichu Hu Chungchun Yang 《分析论及其应用》2005,21(2):101-117
In this paper, we will introduce some problems and results between Diophantine approximation and value distribution theory. 相似文献
102.
G. Saracco F. Geobaldo D. Mazza G. Baldi 《Journal of Thermal Analysis and Calorimetry》1999,56(3):1435-1442
A new method for the synthesis of fine catalyst powders is presented. Catalyst precursors are dissolved in an ethanol-water
mixture which is burned through a nozzle-type burner. As a result, catalyst powders are formed and removed from flue gases
through a filter. LaMnO3 catalysts for the catalytic combustion of methane have been prepared, characterised (TEM, XRD) and compared with a reference
manfacturing method (the citrates one) showing promising, though improvable, results.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
103.
Bioactive paper includes a range of potential paper-based materials that can perform analytical functions normally reserved for multi-well plates in the laboratory or for portable electronic devices. Pathogen detection is the most compelling application. Simple paper-based detection, not requiring hardware, has the potential to have impacts in society, ranging from the kitchen to disasters in the developing world. Bioactive-paper research is an emerging field with significant efforts in Canada, USA (Harvard), Finland and Australia.Following a brief introduction to the material and surface properties of paper, I review the literature. Some of the early work exploits the porosity of paper to generate paper-based microfluidics (“paperfluidics”) devices. I exclude from this review printed electronic devices and plastics-supported devices. 相似文献
104.
Let A and H be Hopf algebra,T-smash product A (∞)T H generalizes twisted smash product A*H.This paper shows a necessary and sufficient condition for T-smash product module category A(∞)T H M to be braided monoidal category. 相似文献
105.
106.
液体轴对称抛撒的实验研究是以云雾爆轰武器的研制为背景的。为了研究轴向气流作用下液体轴对称抛撒二次破碎所形成的雾化场特性,本文利用两台激波管并对之加以改造,成功地在实验室实现了轴向气流作用下液体的轴对称抛撒。为了研究其雾化场的远场特性,本文利用激光粒子测量仪获得了在不同实验工况和不同位置下的雾化场SMD分布曲线。实验数据表明,由于轴向气流速度的增加,液体破碎的Weber数得到了提高,导致二次破碎初期雾化场的SMD随之减小;随着抛撒驱动压力的提高,二次破碎初期雾化场的SMD也随之减小;在同一工况下,雾化场SMD随着测量位置与喷口距离的增加而变大。 相似文献
107.
Noureddine Barka Samir Qourzal Ali Assabbane Abderrahman Nounah Yhya Ait-Ichou 《Arabian Journal of Chemistry》2010,3(4):279-283
The photocatalytic degradation of an azo reactive dye, Reactive Yellow 84 (RY84), in aqueous solutions using industrial titanium dioxide coated non-woven paper was studied. The experiments were carried out to investigate the factors that influence the dye photocatalytic degradation, such as adsorption, initial concentration of dye, temperature, and solution pH. The experimental results show that adsorption is an important parameter controlling the apparent kinetics constant of degradation. The photocatalytic degradation rate was favored by a high concentration of solution in respect to Langmuir–Hinshelwood model. The degradation was enhanced by the temperature and was favored in acidic pH range. 相似文献
108.
Today there is a strong interest in the scientific and industrial community concerning the use of biopolymers for electronic applications, driven mainly by low‐cost and disposable applications. Adding to this interest, we must recognise the importance of the dream of wireless auto‐sustained and low‐energy‐consumption electronics. This dream can be fulfilled by cellulose paper, the lightest and the cheapest known substrate material, as well as the Earth's major biopolymer and of tremendous global economic importance. Most of the paper used up to now is optimised in terms of the required mechanical and physical properties to be used as the support of inks of different origins. In the future, specific electronic heterogeneous paper sheets should be fabricated aiming to get paper fibers with required bulk and surface functionalities, proper water/vapour barrier, size and diameter/thickness of the fibrils and full paper thickness. This will be the function of components/devices to be incorporated/integrated such as thin‐film transistors, complementary metal oxide semiconductor devices, passive electronic components (resistances, inductors and capacitors), memory transistors, electrochromics and thin‐film paper batteries. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
109.
The surface composition of 18th century papers was investigated by means of ToF-SIMS and XPS. The aim of the present study was to explore the possibility of using these surface sensitive methods to obtain information which can help to determine the manufacturing process, provenance and state of conservation of ancient papers. The ToF-SIMS results indicate that the analyzed papers were sized by gelatin and that alum was added as hardening agent. The paper sheets produced in near geographical areas but in different paper mills exhibit a similar surface composition and morphology of the fibers as shown by the ToF-SIMS measurements. The ToF-SIMS and the XPS results indicate that a significant fraction of the cellulose fibers is not covered by the gelatin layer. This was observed for the ancient papers and for a modern handmade paper manufactured according to the old recipes. 相似文献
110.
Lin Zhu Jining HeDianran Yan Yanchun DongJianxin Zhang Xiangzhi LiHanlin Liao 《Applied Surface Science》2011,257(23):10282-10288
In the present study, Fe-Al2O3-FeAl2O4 composite coatings were successfully deposited by reactive plasma sprayed Al/Fe2O3 agglomerated powder. Phase composition and microstructure of the coatings were determined by XRD and SEM. The results indicated that the composite coatings were principally composed of three different phases, i.e. FeAl2O4 phase as main framework, dispersed ball-like Fe-rich phase, and small splats of Al2O3 phase, and it was thought that the in situ synthesized metal phase was helpful to toughen the coating matrix. According to the results of the indentation and frictional wear tests, the composite coating exhibited excellent toughness and anti-friction properties in comparison with conventional Al2O3 monophase coating, though its microhardness value was a little lower than that of Al2O3 coating. The formation mechanism and the toughening mechanism of the composite coating were clarified in detail. 相似文献