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1.
Molecular structure and granule morphology of native and heat‐moisture‐treated pinhão starch 下载免费PDF全文
Vania Z. Pinto Khalid Moomand Nathan L. Vanier Rosana Colussi Franciene A. Villanova Elessandra R. Zavareze Loong‐Tak Lim Alvaro R. G. Dias 《International Journal of Food Science & Technology》2015,50(2):282-289
Pinhão seed is an unconventional source of starch and the pines grow up in native forests of southern Latin America. In this study, pinhão starch was adjusted at 15, 20 and 25% moisture content and heated to 100, 110 and 120 °C for 1 h. A decrease in λ max (starch/iodine complex) was observed as a result of increase in temperature and moisture content of HMT. The ratio of crystalline to amorphous phase in pinhão starch was determined via Fourier transform infra red by taking 1045/1022 band ratio. A decrease in crystallinity occurred as a result of HMT. Polarised light microscopy indicated a loss of birefringence of starch granules under 120 °C at 25% moisture content. Granule size distribution was further confirmed via scanning electron microscopy which showed the HMT effects. These results increased the understanding on molecular and structural properties of HMT pinhão starch and broadened its food and nonfood industrial applications. 相似文献
2.
3.
Manku T. McGregor J.M. Nathan A. Roulston D.J. Noel J.-P. Houghton D.C. 《Electron Devices, IEEE Transactions on》1993,40(11):1990-1996
Results of the drift hole mobility in strained and unstrained SiGe alloys are reported for Ge fractions varying from 0 to 30% and doping levels of 1015-1019 cm-3. The mobilities are calculated taking into account acoustic, optical, alloy, and ionized-impurity scattering. The mobilities are then compared with experimental results for a boron doping concentration of 2×1019 cm-3. Good agreement between experimental and theoretical values is obtained. The results show an increase in the mobility relative to that of silicon 相似文献
4.
Godfrey C. Onwubolu Petr Buryan Frank Lemke 《The International Journal of Advanced Manufacturing Technology》2008,39(11-12):1080-1092
This paper presents an enhanced approach to predictive modeling for determining tool-wear in end-milling operations based on enhanced-group method of data handling (e-GMDH). Using milling input parameters (speed, feed, and depth-of-cut) and response (tool wear), the data for the model is partitioned into training and testing datasets, and the training dataset is used to realize a predictive model that is a function of the input parameters and the coefficients determined. In our approach, we first present a methodology for modeling, and then develop predictive model(s) of the problem being solved in the form of second-order equations based on the input data and coefficients realized. This approach leads to some generalization because it becomes possible to predict not only the test data obtained during experimentation, but other test data outside the experimental results can also be used. Moreover, this approach makes it easy to present the realized solution in a form that can be further optimized for the input parameters using some optimization techniques. The results realized using our e-GMDH method are promising, and the comparative study presented shows that the e-GMDH outperforms polynomial neural network (PNN); moreover, it is more flexible than the conventional GMDH, which tends to produce nonlinear solutions even for simple problems. In the investigation, the extended particle swarm optimization (PSO) technique was applied to obtain the optimal parameters. Consequently, the modeling approach is extremely useful in realizing a computer-aided process-planning system in an advanced manufacturing environment. 相似文献
5.
The electron drift mobility for unstrained and coherently strained Si1-xGex grown on a <001> silicon substrate is analytically obtained for Ge fractions less than 30%. The method is based on the following two assumptions: the conduction bands of the unstrained alloy are Si-like for Ge fraction less than 30%, and in the case of the coherently strained alloy, strain-induced energy shifts occur in the conduction band valleys. The shifts in energy yield two different mobility values: one corresponding to the growth plane with a value larger than the unstrained mobility, and the other parallel to the growth direction and correspondingly smaller in value. In comparison to silicon, the results show a degradation of both the unstrained mobilities for doping levels up to 1017 cm-3. Beyond this doping level, the strained mobility component parallel to the growth direction becomes slightly larger than the mobility of silicon 相似文献
6.
M Nathan 《Canadian Metallurgical Quarterly》1994,70(1):49-50
Two cases of umbilical warts are described. The occurrence of these lesions was not previously known. In both cases there was a history of long-standing genital warts. 相似文献
7.
Xiang Lu S. Sundar Kumar Iyer Jin Lee Brian Doyle Zhineng Fan Paul K. Chu Chenming Hu Nathan W. Cheung 《Journal of Electronic Materials》1998,27(9):1059-1066
We have demonstrated feasibility to form silicon-on-insulator (SOI) substrates using plasma immersion ion implantation (PIII)
for both separation by implantation of oxygen and ion-cut. This high throughput technique can substantially lower the high
cost of SOI substrates due to the simpler implanter design as well as ease of maintenance. For separation by plasma implantation
of oxygen wafers, secondary ion mass spectrometry analysis and cross-sectional transmission electron micrographs show continuous
buried oxide formation under a single-crystal silicon overlayer with sharp Si/SiO2 interfaces after oxygen plasma implantation and high-temperature (1300°C) annealing. Ion-cut SOI wafer fabrication technique
is implemented for the first time using PIII. The hydrogen plasma can be optimized so that only one ion species is dominant
in concentration and there are minimal effects by other residual ions on the ion-cut process. The physical mechanism of hydrogen
induced silicon surface layer cleavage has been investigated. An ideal gas law model of the microcavity internal pressure
combined with a two-dimensional finite element fracture mechanics model is used to approximate the fracture driving force
which is sufficient to overcome the silicon fracture resistance. 相似文献
8.
Coupled electrothermal modeling of microheaters using SPICE 总被引:2,自引:0,他引:2
In this paper,,we report a novel simulation approach that computes both the transient and steady state electrothermal behavior in integrated circuit (IC) compatible thermally isolated microheaters. The resulting distribution of heat, current density and temperature, as well as the electrical terminal behavior have been obtained for realistic device structures. The results are based on a two-dimensional solution of the coupled system of partial differential equations that govern both electrical and heat transport in the device. Unlike standard numerical approaches for coupled systems, our technique is based on the behavioural models, available in most commercial circuit simulators (e.g., HSPICE), that allow synthesis of complex, nonlinear, and coupled circuit elements. The simulation results are in excellent agreement with measurement data of steady state and transient terminal characteristics, obtained under conditions of vacuum. We note that this modeling approach allows concurrent simulation (and subsequent optimization) of the performance of both the control electronics as well as the thermal element(s), within the same IC design environment 相似文献
9.
Randal A.Lemke 《现代音响技术》2004,(7):82-83
我今天很高兴能来到这里与你们一起讨论关于AV通信产业所面临的全球性机遇以及中国AV通信产业如何随着世界市场共同成长的问题。从某种意义上讲,我们所面临的机遇是无限的,因为对于政府、商务、教育和几乎其他所有机构的未来通信基础构造而言,AV通信将是极其关键的。 相似文献
10.
Elizabeth J. Opila Nathan S. Jacobson Dwight L. Myers Evan H. Copland 《JOM Journal of the Minerals, Metals and Materials Society》2006,58(1):22-28
The importance of understanding and predicting the interactions of oxides with water vapor at high temperatures is demonstrated
in this article. Methods for observing volatilization phenomena and identifying the chemical formulae for volatile metal hydroxides
are discussed. In addition, techniques for obtaining accurate thermodynamic data for gaseous metal hydroxide species are described.
Detailed examples of the stability of the principle structural and/or protective oxides chromia (Cr2O3), silica (SiO2), and alumina (Al2O3) in high-temperature water vapor are included. 相似文献