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891.
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Masni Mat Yusoff Chin Ping Tan Yaakob Bin Che Man Mat Sahri Miskandar Sivaruby Kanagaratnam Imededdine Arbi Nehdi 《Journal of the American Oil Chemists' Society》2013,90(1):91-101
Thirteen fat blends intended for cookie filler (CF) production that consist of 20–70 % palm mid-fraction (PMF), 20–70 % virgin coconut oil (VCO), and 0–10 % palm stearin (POs) were developed based on the solid fat contents (SFC) of the fat portions extracted from five commercial CF samples: A, B, C, D, and E. A mixture design was applied for fat blend optimization, and the combination that best approached the target SFC values was composed of 70 % PMF, 20 % VCO, and 10 % POs. The optimized coconut- and palm-based fat blend (O-CP) exhibited a steeper SFC profile, with 8.2 % (±0.2) SFC at 25 °C (room temperature) and 0.2 % (±0.2) SFC at 37 °C (body temperature); lower slip melting point of 34.0 °C (±0.0); and a lower iodine value (IV) of 40.25 g/100 g (±1.04). In addition, O-CP contained higher proportions of medium-chain fatty acids (MCFA) and lauric acid (C12:0) of 3.2 % (±0.18) and 9.7 % (±0.43), respectively. In terms of its thermal profile, O-CP showed no significant difference in terms of its crystallization range, 49.7 °C (±2.66) with the exception of sample C, but it exhibited a smaller melting range, 65.8 °C (±1.47), compared to the fat portions of the commercial samples. The ranges represented the span between the onset and offset temperatures of both crystallization and melting profiles as determined by differential scanning calorimetry. 相似文献
894.
One clinical precedent for the use of nanosized imaging agents is the localization of the tumor draining sentinel lymph nodes. In this application, radiocolloids such as (99m)Tc-NanoColl are currently used to plan the surgical procedure and to provide acoustic guidance during the intervention. Additional injections of dyes are common to provide optical surgical guidance. Bimodal imaging agents, which are both radioactive and fluorescent, have the potential to be used for both surgical planning and intraoperative fluorescence guidance towards the sentinel lymph nodes. This review provides an overview of the radioactive, fluorescent, and size properties of (non-targeted) bimodal nanoparticles, and their (potential) value in sentinel lymph node detection. 相似文献
895.
J. M. Chin J. C. H. Phang D. S. H. Chan M. Palaniappan G. Gilfeather C. E. Soh 《Microelectronics Reliability》2001,41(8):249
Semiconductor industry is continuously experiencing shrinking device features and a tremendous increase in the number of transistors in an integrated circuit (IC). The application of the optical beam induced currents (OBIC) technique in ICs is more difficult and mainly limited to a few transistors near the input–output pins of an IC. The single contact optical beam induced currents (SCOBIC) is a new device and failure analysis technique, that makes it possible to perform the similar OBIC technique on many transistor including internal junction on an IC. This is done by connecting the substrate or power pins of an IC circuit to the current amplifier. In contrast, in the OBIC technique, only the junction directly connected to the current amplifier is imaged. The implementation of the SCOBIC approach is discussed and experimental results which demonstrates the SCOBIC approach is presented. Application of the SCOBIC technique from the backside of an IC, which further enhances the technique, is also discussed. 相似文献
896.
Two suboptimal algorithms are proposed for downlink beamforming in FDD DS-CDMA mobile radio by using uplink beamforming weights. One is a null-constrained method, which maintains the same null positions for both uplink and downlink beam patterns; the other is a frequency-calibrated method which constrains the same main beam positions for both patterns. We also evaluate the multicell downlink capacity of DS-CDMA systems using a per-user-per-weight beamforming scheme. Outer cell interference is modeled as an AWGN process whose variance is proportional to the average intracell total transmitted power. Computer simulations are given to compare the single cell and multicell capacities using different downlink beamforming weight generation algorithms 相似文献
897.
Downlink channel covariance matrix (DCCM) estimation and itsapplications in wireless DS-CDMA systems
The downlink channel covariance matrix (DCCM) is of vital importance in determining downlink beamforming weights for base station (BS) antenna array systems. For the frequency-division-duplex (FDD) mode, DCCM is difficult to obtain due to a lack of direct measurement of downlink channel responses. In this paper, a novel technique is proposed for estimating DCCM using uplink channel responses only, which does not need direction-of-arrival (DOA) estimation and its association. The downlink beamforming scheme is then proposed for wireless DS-CDMA systems, using the obtained DCCM information together with the so-called virtual uplink beamforming and power control technique. Computer simulations show that using the BS antenna array together with this new beamforming technique can provide larger system capacity than traditional DOA-based approaches, which just direct the main beam toward the desired user 相似文献
898.
899.
For thin oxides grown on high temperature formed Si0.3Ge0.7, the gate oxide quality is strongly dependent on oxide thickness and improves as thickness reduces from 50 to 30 Å. The thinner 30 Å oxide has excellent quality as evidenced by the comparable leakage current, breakdown voltage, interface-trap density and charge-to-breakdown with conventional thermal oxide grown on Si. The achieved good oxide quality is due to the high temperature formed Si0.3Ge0.7 that is strain relaxed and stable during oxidation. The possible reason for strong thickness dependence may be due to the lower GeO2 content formed in thinner 30 Å oxide rather than strain relaxation related rough surface or defects 相似文献
900.
Pin J. Wang Jong S. Kim Dongwook Kim Chin C. Lee 《Journal of Materials Science: Materials in Electronics》2009,20(4):334-342
A novel fluxless bonding process of silicon wafer on molybdenum substrate is successfully developed. Si-to-Mo bonding can be used for packaging power devices, especially when a device consists of an entire wafer. 300 Å Cr layer and 1,000 Å Au layer are first deposited on Si wafers and Mo substrates. The Cr/Au dual layer is used as underbump metallurgy and seed layer of electroplating. To reduce plastic shear strain on the solder in a bonded pair, thick Sn layer (70 μm) is electroplated over Mo substrates having Cr/Au structure, followed immediately by thin (0.1 μm) Ag layer. This Ag layer acts as the capping layer to prevent inner Sn from oxidation. The bonding process is performed in 50 millitorrs vacuum to inhibit oxidation. The bonding condition is 290 °C for 15 min without the use of any flux. The bonding layer thickness is controlled at 50 μm by small spacers placed between Si wafer and Mo substrate. Microstructure and composition of the joints are studied under scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). Scanning acoustic microscopy (SAM) is also used to verify the quality of joints over the entire sample. Without using any flux, high quality and uniform bonding layer is achieved. The composition of the joint is more than 97 at.% Sn. No intermetallic compound layers exist in the joint. This novel fluxless bonding process should be valuable in packaging large high power devices. 相似文献