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41.
42.
Anuradee Witthayapanyanon Tri Thanh Phan Todd C. Heitmann Jeffrey H. Harwell David A. Sabatini 《Journal of surfactants and detergents》2010,13(2):127-134
Extended surfactants containing an intermediate-polarity spacer, such as polypropylene oxide, in between the hydrophilic head and the hydrocarbon tail are known to result in superior solubilization and low interfacial tension, though they exhibit slow kinetics. The present work seeks to evaluate both equilibrium and kinetic aspects of extended-surfactant-based micro- and macroemulsions. The interfacial morphology of the extended surfactant membrane, i.e., characteristic length (ξ) and interfacial rigidity (E r) at optimum middle-phase microemulsion conditions, was characterized using the net-average curvature model. The results showed that extended surfactants resulted in a relatively rigid interfacial membrane compared with conventional surfactants having similar hydrocarbon chain length. In addition, both ξ and E r parameters increased with the length of the polypropylene oxide spacer. Increasing E r values correlated to the slow coalescence rates of extended surfactant emulsified systems. Two alternative approaches (the addition of combined linkers and co-surfactant) are shown to overcome the slow kinetics of coalescence while maintaining desirable high solubilization and low interfacial tension. 相似文献
43.
Yoshimasa Yamamoto Phan Trung Nghia Warunee Klinklai Takayuki Saito Seiichi Kawahara 《应用聚合物科学杂志》2008,107(4):2329-2332
The removal of proteins from natural rubber through a batch process was studied by the incubation of the rubber latex with urea in the presence of sodium dodecyl sulfate. Under suitable conditions, the total nitrogen content of deproteinized natural rubber (DPNR) decreased from 0.38 to 0.02 wt % after incubation for 10 min; this was similar to that of the rubber deproteinized with a proteolytic enzyme for 12 h. For applications, continuous incubation and centrifugation were individually investigated by the use of a semicircular channel and a continuous centrifuge, respectively, to scale up DPNR preparation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
44.
I-Fang Lee Thien Q. Phan Lyle E. Levine Jonathan Z. Tischler Peter T. Geantil Yi Huang Terence G. Langdon Michael E. Kassner 《Acta Materialia》2013,61(20):7741-7748
Aluminum alloy 1050 was processed by equal-channel angular pressing (ECAP) using a single pass (equivalent uniaxial strain of about 0.88). Long-range internal stresses (LRISs) were assessed in the grain/subgrain interiors using X-ray microbeam diffraction to measure the spacing of {5 3 1} planes, with normals oriented approximately +27.3°, +4.9° and ?17.5° off the pressing (axial) direction. The results are consistent with mechanical analysis that suggests the maximum tensile plastic-strain after one pass is expected for +22.5°, roughly zero along the pressing axis, and maximum compressive strain for the ?67.5° direction. The magnitude of the measured maximum compressive long-range internal stress is about 0.13σa (applied stress) in low-dislocation regions within the grain/subgrain interiors. This work is placed in the context of earlier work where convergent beam electron diffraction was used to analyze LRISs in close proximity to the deformation-induced boundaries. The results are complementary and the measured stresses are consistent with a composite model for long-range internal stresses. 相似文献
45.
Anh Tuan Thanh Pham Oanh Kieu Truong Le Dung Van Hoang Truong Huu Nguyen Trang Huyen Cao Pham Phuong Thanh Ngoc Vo Thang Bach Phan Vinh Cao Tran 《Journal of the European Ceramic Society》2021,41(6):3493-3500
Structure modification has been found to tune significantly the transparent-conducting performance, especially mobility and conductivity of hydrogenated Ga-doped ZnO (HGZO) films. The strong correlation between film thickness and mobility of the films is revealed. The mobility increases quickly with increasing the thickness from 350 to 900 nm, and then tends to be saturated at further thicknesses. A higher mobility than 50 cm2/Vs can be achieved, which is an extra-high value for polycrystalline ZnO films deposited by using the sputtering technique. The thickness-dependent mobility originates from scatterings on grain boundaries and dislocation-induced defects controlled by thin-film growth. Based on the Volmer-Weber model, an expansion model is built up to describe the thickness-dependent crystal growth of the HGZO films, especially at the thick films. As a result, the 800 nm-thick HGZO film obtains the highest performance with high mobility of 51.5 cm2/Vs, low resistivity of 5.3 × 10?4 Ωcm, and good transmittance of 83.3 %. 相似文献
46.
To create a programming environment for contract dispute resolution, we propose an extension of assumption-based argumentation
into modular assumption-based argumentation in which different modules of argumentation representing different knowledge bases
for reasoning about beliefs and facts and for representation and reasoning with the legal doctrines could be built and assembled
together. A distinct novel feature of modular argumentation in compare with other modular logic-based systems like Prolog
is that it allows references to different semantics in the same module at the same time, a feature critically important for
application of argumentation in legal domains like contract dispute resolution where the outcomes of court cases often depend
on whether credulous or skeptical modes of reasoning were applied by the contract parties. We apply the new framework to model
the doctrines of contract breach and mutual mistake. 相似文献
47.
In this paper, the influence of polycrystalline silicon as a protective field shield on the reliability and stability of piezoresistive silicon sensors is investigated. For this purpose, the behaviour of piezoresistive sensors with and without polycrystalline silicon shield is observed under changes of environmental condition, such as relative humidity and temperature. The obtained sensor-offset change under humidity stimulation is smaller than that observed by temperature excitation. The samples with polycrystalline silicon shield exhibit a lower humidity and temperature coefficients as compared to the samples without this shield. The values of uncertainties in measurement are evaluated according to the ISO “Guide to the Expression of Uncertainties in Measurement” (GUM). The uncertainty contribution caused by internal disturbing of the sensors can be neglected. Comparing two types of piezoresistive sensors investigated, the samples with polycrystalline silicon shield produce a considerably reduction of all measurement uncertainty contributions. The results show that an additional polycrystalline silicon shield between two insulating layers connected to the supply voltage, which provides a determined potential distribution inside the passivation layer stack, improves the device reliability and the accuracy of measurement. 相似文献
48.
49.
In this paper, we propose a two-mode adaptive fuzzy controller with approximation error estimator. In the learning mode, the controller employs some modified adaptive laws to tune the fuzzy system parameters and an approximation error estimator to compensate for the inherent approximation error. In the operating mode, the fuzzy system parameters are fixed, only the estimator is updated online. Mathematically, we show that the closed-loop system is stable in the sense that all the variables are bounded in both modes. We also establish mathematical bounds on the tracking error, state vector, control signal and the RMS error. Using these bounds, we show that controller's design parameters can be chosen to achieve desired control performance. After that, an algorithm to automatically switch the controller between two modes is presented. Finally, simulation studies of an inverted pendulum system and a Chua's chaotic circuit demonstrate the usefulness of the proposed controller. 相似文献
50.
Dinh Thuy Phan Huy Jonathan Rodriguez Atílio Gameiro Rahim Tafazolli 《Wireless Personal Communications》2007,43(4):1727-1740
The Multicarrier CDMA Transmission Techniques for Integrated Broadband Cellular Systems (MATRICE) project addresses a candidate
solution for a Beyond 3G (B3G) air-interface based on Multi-Carrier Code Division Multiple Access (MC-CDMA). It investigates
dynamic resource allocation strategies at the Medium Access Control (MAC) layer to support the transport of Internet Protocol
(IP) packets over the air-interface in a cost effective manner and maximise the cell capacity with a target QoS. A candidate
Dynamic Resource Allocation (DRA) protocol architecture is proposed that is based on cross-layer signalling to provide reactive
resource allocation according to the fast channel and traffic variations. In-line with B3G expectations, the proposed DRA
handles a very large number of users with inherent flexibility and granularity necessary to support heterogeneous traffic,
and still with limited complexity. Thanks to the modular architecture of the DRA, various scheduling policies are investigated
and compared in terms of capacity and reactivity to the system environment. Simulation results have shown that the MATRICE
system has the potential to deliver broadband heterogenous services in a cost-effective manner, and emerge as a propespective
candidate air-interface for B3G cellular networks. 相似文献