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1.
This paper describes the methodology for simulating a reprographic ink with a ceramic ink based on a commercially available zirconia powder for direct ceramic ink-jet printing. Of over-riding importance was matching viscosity and this was tested systematically by using a mineral oil–hexane binary system. Of secondary importance was adjustment of the pressure defect behind the nozzle to compensate for small differences in surface tension. The inks tested in the wide array print-head were based on low electrical conductivity liquids to avoid damage to the electroding system. The organic binder for the zirconia ink was paraffin wax and the dispersant was a hydroxystearic acid based polyester. 相似文献
2.
R. Morena P. E. Lockwood L. Evans C. W. Fairhurst 《Journal of the American Ceramic Society》1986,69(4):75-C-
The effect on mechanical behavior of ZrO2 additions to a dental porcelain was investigated. The ZrO2 was introduced into the glassy matrix phase of the porcelain by refritting the all-glass porcelain constituent. X-ray diffraction indicated that a sizeable fraction of the ZrO2 was retained in the tetragonal form after the porcelain was fired. Zirconia additions to the porcelain produced substantial improvements in fracture toughness, strength, and thermal shock resistance. 相似文献
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4.
Valentina I. Simagina Pavel A. Storozhenko Olga V. Netskina Oksana V. Komova Galina V. Odegova Yury V. Larichev Arcady V. Ishchenko Anna M. Ozerova 《Catalysis Today》2008,138(3-4):253
Catalytic hydrolysis of NaBH4 and NH3BH3 has been studied. It was shown that the nature of the support and the active component of the catalyst affect the H2 generation rate. Despite similar sizes of rhodium particles formed on the surface of different supports (γ-Al2O3, TiO2, carbon), their reactivity is different. Rh/TiO2 with low rhodium concentration (1 wt.%) is the most active catalyst both in the hydrolysis of NaBH4 and NH3BH3. The obtained results show that the rhodium chloride interaction with titania determines the reactivity of rhodium particles formed under action of NaBH4 medium. TEM, DRS UV–vis and XPS were used to characterize the catalysts. 相似文献
5.
Ottavia Colombo Simona Villani Giovanna Pinelli Claudia Trentani Maurizia Baldi Orazio Tomarchio Anna Tagliabue 《Nutrition journal》2008,7(1):5
Background
Excess body fat is a major risk factor for disease primarily due to its endocrine activity. In recent years several criteria have been introduced to evaluate this factor. Nevertheless, treatment need is currently assessed only on the basis of an individual's Body Mass Index (BMI), calculated as body weight (in kg) divided by height in m2. The aim of our study was to determine whether application of the BMI, compared to adiposity-based criteria, results in underestimation of the number of subjects needing lifestyle intervention. 相似文献6.
Present-day computer-aided design (CAD) packages play only a small part in the area of mechanical engineering design, which involves the synthesis and embodiment of physical components to perform a pre-determined function without unwanted side effects. The computer cannot properly help the designer in this task until it is able to capture and process the function requirements of the design. This paper describes the computer system being developed for this purpose at the Engineering Design Centre at Cambridge University Engineering Department. The paper also explores some of the geometrical and programming implications raised. 相似文献
7.
Papandriopoulos J. Evans J. Dey S. 《Wireless Communications, IEEE Transactions on》2005,4(6):2705-2715
How can we achieve the conflicting goals of reduced transmission power and increased capacity in a wireless network, without attempting to follow the instantaneous state of a fading channel? In this paper, we address this problem by jointly considering power control and multiuser detection (MUD) with outage-probability constraints in a Rayleigh fast-fading environment. The resulting power-control algorithms (PCAs) utilize the statistics of the channel and operate on a much slower timescale than traditional schemes. We propose an optimal iterative solution that is conceptually simple and finds the minimum sum power of all users while meeting their outage targets. Using a derived bound on outage probability, we introduce a mapping from outage to average signal-to-interference ratio (SIR) constraints. This allows us to propose a suboptimal iterative scheme that is a variation of an existing solution to a joint power control and MUD problem involving SIR constraints. We further use a recent result that transforms complex SIR expressions into a compact and decoupled form, to develop a noniterative and computationally inexpensive PCA for large systems of users. Simulation results are presented showing the closeness of the optimal and mapped schemes, speed of convergence, and performance comparisons. 相似文献
8.
The vast majority of recombinant polytropic murine leukemia viruses (MuLVs) generated in mice after infection by ecotropic MuLVs can be classified into two major antigenic groups based on their reactivities to two monoclonal antibodies (MAbs) termed Hy 7 and 516. These groups very likely correspond to viruses formed by recombination of the ecotropic MuLV with two distinct sets of polytropic env genes present in the genomes of inbred mouse strains. We have found that nearly all polytropic MuLVs identified in mice infected with a substrain of Friend MuLV (F-MuLV57) are reactive with Hy 7, whereas mice infected with Moloney MuLV (Mo-MuLV) generate major populations of both Hy 7- and 516-reactive polytropic MuLVs. We examined polytropic MuLVs generated in NFS/N mice after inoculation with Mo-MuLV-F-MuLV57 chimeras to determine which regions of the viral genome influence this difference between the two ecotropic MuLVs. These studies identified a region of the MuLV genome which encodes the nucleocapsid protein and a portion of the viral protease as the only region that influenced the difference in polytropic-MuLV generation by Mo-MuLV and F-MuLV57. 相似文献
9.
The authors have exploited the ideas used in vector quantisation for error recovery of scalar quantised LSFs. The good performance of this method has provided high resistance of the LSFs to channel errors, outperforming other schemes by, possibly, a considerable margin. Better objective and subjective performances were obtained with this new method which obviates the need for more powerful FEC schemes for transmission over noisy channels.<> 相似文献
10.