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Unmodified natural clay particles, halloysite nanotubes (HNTs; l = 800 nm, douter = 50 nm, dinner = 15 nm), are used to stabilize oil-in-water Pickering emulsions (PEs). The hydrophilic HNTs are laterally attached to the oil/water interface and accumulate in bundles because of capillary forces. The nanotubes cover the oil droplets and prevent them from coalescing. The influence of HNT concentration on the oil droplet size and stability of the emulsions is investigated. An increase in the HNT concentration results in a nonmonotonous decrease in the droplet size, which can be attributed to changes in the packing parameter. The high mechanical stability of PEs allows for the separation of the oil droplets from the continuous phase by membrane filtration, and the emulsion phase could be highly concentrated up to around 90 vol % oil phase fraction. This study facilitates an accurate and more efficient application of HNT-stabilized PEs, e.g., for recyclable or continuous liquid/liquid reaction systems. [ABSTRACT FROM AUTHOR]

SUMMARY A number of recent studies on neural networks (NNs) have been conducted with the purpose of applying engineering to the brain function. One approach which focuses on the dynamics of the living organism, various Artificial Neural Networks (ANNs) has been proposed. However, the NN of a living body is very large in scale. Therefore, when we analyze the dynamics using the hardware NN model, the number of devices and the circuit size should be smaller. In this paper, we aim to reduce the area of a cell body model, and look into the cell body model made up of only NMOS. As a result, it is clearly shown that the packaging density of the proposed model can reduce the size of a traditional model by more than half. [ABSTRACT FROM AUTHOR]

We report on a model chemotherapy drug delivery system comprising nonionic surfactant vesicles (niosomes) packaged within a temperature-sensitive chitosan network. This smart packaging, or package-within-a package system, provides two distinct advantages. First, the gel prevents circulation of the niosomes and maintains delivery in the vicinity of a tumor. Second, the chitosan network protects the niosomes against fluctuations in tonicity, which affects delivery rates. Tonicity is the sum of the concentrations of the solutes which have the capacity to exert an osmotic force across the membrane. All release rate experiments were conducted with 5,6-carboxyfluorescein, a fluorescent dye. Release rates were monitored from both bare niosomes alone and niosome-embedded, chitosan networks. It was observed that chitosan networks prolonged delivery from 100 h to 55 days in low ionic strength environment and pH conditions similar to a tumor site. The primary effect of chitosan is to add control on release time and dosage, and stabilize the niosomes through a high ionic strength surrounding that prevents uncontrolled bursting of the niosomes. Secondary factors include crosslink density of the chitosan network, molecular weight of the individual chitosan polymers, dye concentration within the niosomes, and the number density of niosomes packaged within the chitosan network. Each of these factors can be altered to fine-tune release rates. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 100A:3296-3303, 2012. [ABSTRACT FROM AUTHOR]

Microscale thermoelectric cooling elements (TECs) are being proposed to cool down an integrated circuit to maintain its performance. The maximum cooling power of microscale TECs is significantly reduced by the interfacial resistance. For our particular application, we calculate the optimal dimension of the TECs, made of Bi2Te3, that reduce the temperature at a hotspot on an IC chip by 10°C. By the one-dimensional analytical model that we developed and numerical solutions of TEC equations using MATLAB©, we obtain performance characteristics that relate the cooling power density to other control variables and material constants. The optimal dimension of microscale TECs is calculated for cooling at a hotspot region by a range of temperature differences, for example from 10°C to 50°C. Further, the percentage change in the optimal thickness for various thermal resistances and electrical contact resistances can be predicted. These results act as a good guideline for two-dimensional analysis and assembly of TECs. [ABSTRACT FROM AUTHOR]

In this paper, we investigate fully embedded circular spiral inductors in multilayered organic packaging substrate for radio-frequency (RF) and microwave applications. The proposed spiral inductors are designed with circular geometry to improve their quality factors and the vertically stacked geometry is utilized to reduce the component area resulting in the increment of packaging density. And also the embedded circular spiral inductors are designed with conductor backed coplanar waveguide (CBCPW) structures for utilizing them directly for compact RF modules and systems. They are evaluated and optimized by varying their geometry parameters such as a number of turns, inner diameter, and embedded layer. These embedded inductors are accurately designed and analyzed by 3-D EM simulation and equivalent circuit modeling. The planar circular spiral two-turn inductor has inductance of 8.6 nH and maximum quality factor of 67 at 1 GHz. The vertically stacked circular spiral two-turn inductor has inductance of 10.2 nH and maximum quality factor of 66 at 1 GHz. The size of the vertically stacked inductor is approximately 70% of the planar one. The measured performance characteristics are well matched with the 3-D EM simulated ones. [ABSTRACT FROM AUTHOR]

The thermal performance of a deep UV LED package in three different chip on board (COB) substrates was studied by finite element simulation. The relationship between the temperature of each component in different COB substrates and the packaging density of the deep UV LED was analyzed. Having the same size of a 1313 COB substrate, this study indicates that the aluminum substrate can adapt to a 0.38 W/mm2 packaging density at a maximum owing to the existence of an insulation layer, which has a low thermal conductivity. However, an alumina ceramic substrate can be adapted to a 0.94 W/mm2 packaging density. Aluminum nitride ceramic can meet the demand for a higher packaging density; however, the cost is a key factor which cannot be ignored for large-scale applications. The results of this study provide detailed suggestions for researchers and industrial use for the selection of COB substrates packaged with deep UV LED according to different packaging densities, which have a higher practical application value. [ABSTRACT FROM AUTHOR]

We have developed a modular jack type Mini-MT that employs a compact two-fiber ferrule in a housing. The connector mechanism is similar to that of a conventional electric modular jack type connector. The connector also has a locking mechanism to prevent accidental disconnection and a high packaging density of 2 fibers/cm2. Fabricated connectors for single-mode two-fiber ribbons exhibit a low insertion loss of 0.17 dB and a high return loss of more than 40 dB [ABSTRACT FROM PUBLISHER]