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991.
Mixing a bis‐hydrophilic, cationic miktoarm star polymer with a linear polyanion leads to the formation of unilamellar polymersomes, which consist of an interpolyelectrolyte complex (IPEC) wall sandwiched between poly(ethylene oxide) brushes. The experimental finding of this rare IPEC morphology is rationalized theoretically: the star architecture forces the assembly into a vesicular shape due to the high entropic penalty for stretching of the insoluble arms in non‐planar morphologies. The transmission electron microscopy of vitrified samples (cryogenic TEM) is compared with the samples at ambient conditions (in situ TEM), giving one of the first TEM reports on soft matter in its pristine environment.

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992.
Exclusive organic templating of macroporous oxide films is reported by using non‐close and lose packing of spherical copolymer aggregates, in combination with facile control of condensation degree/density of inorganic oxide frameworks. Unique macroporous oxide films, mainly titania showing highly porous, crystalline, and versatile properties, can be fabricated with continuous design from unusual 3‐D net‐shape to tunable spherical macrostructures, which expands the preparation of other inorganic oxide films (silica, alumina, and zirconia) and possibly adapts the use of other assembled organic polymers. The macroporous structures are helpful for effective accommodation of bulky biomoleculeshigh and diffusivity of organic molecules (useful for photocatalysts). Unusual structural variation, expansion of spherical voids, is also observed, being useful for fine tuning of optical property.  相似文献   
993.
We present a computer study of the association behavior of copolymer chains with a gradient part and soluble tail of variable length. As a simulation method we use dynamic Monte Carlo simulation on a simple cubic lattice with pair interaction parameters. The solvent quality and selectivity is modeled by the variation of pair interaction parameters between nearest neighbors on the lattice. The role of the length of soluble part in the self‐assembly and its effect on the structure of aggregates was the main goal of this work. The size and structure of aggregates were analyzed using an improved topological classification method which has been developed and tested in the present study. The structure and association numbers of aggregates were compared with those of linear diblock copolymers.

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994.
Polydiacetylenes have received intense attention on account of their well‐established chromic alterations that are detectable often by the naked eye, making them ideal for a variety of applications such as biosensory materials. These polymers have been fabricated in a variety of materials platforms including 3D crystals, 2D monolayers, and 0D spherical vesicles; however, 1D morphologies that might be useful for directional energy migration are less common. This article describes the development and current research efforts of protein‐based 1D nanowire‐like supramolecular assemblies with embedded polydiacetylenes.

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995.
The paper studies arbitrage opportunities and possible speculative opportunities for diffusion mean‐reverting market models. It is shown that the Novikov condition is satisfied for any time interval and for any set of parameters. It is non‐trivial because the appreciation rate has Gaussian distribution converging to a stationary limit. It follows that the mean‐reverting model is arbitrage‐free for any finite time interval. Further, it is shown that this model still allows some speculative opportunities: a gain for a wide enough set of expected utilities can be achieved for a strategy that does not require any hypothesis on market parameters and does not use estimation of these parameters.  相似文献   
996.
Transdermal drug delivery (TDD) systems with feedback control have attracted extensive research and clinical interest owing to their unique advantages of convenience, self‐administration, and safety. Here, a self‐powered wearable iontophoretic TDD system that can be driven and regulated by the energy harvested from biomechanical motions is proposed for closed‐loop motion detection and therapy. A wearable triboelectric nanogenerator (TENG) is used as the motion sensor and energy harvester that can convert biomechanical motions into electricity for iontophoresis without stored‐energy power sources, while a hydrogel‐based soft patch with side‐by‐side electrodes is designed to enable noninvasive iontophoretic TDD. Proof‐of‐concept experiments on pig skin with dyes as model drugs successfully demonstrate the feasibility of the proposed system. This work not only extends the application of TENG in the biomedical field, but may also provide a cost‐effective solution for noninvasive, electrically assisted TDD with closed‐loop sensing and treatment.  相似文献   
997.
电子吊舱在外军的电子战装备中有着举足轻重的地位,在几次局部战争中发挥了巨大的作用。文中介绍了电子吊舱的设计及其应用,首先介绍了电子吊舱的分类及其功能,介绍了电子吊舱的系统组成及设计重点,然后分析了电子吊舱收发隔离及在压制干扰情况下对雷达的干扰效能,最后给出了典型的试验结果。  相似文献   
998.
Nanovolcano arrays were fabricated by electrodepositing Ni/Cu alloys into a monolayer of self‐assembled nanospheres and then electrochemically etching the deposited alloy film. The fabricated nanovolcano arrays feature highly ordered hexagonally arranged concave nanobowls decorated with triangular nanopores at their interstices. After coated with Ag, the nanovolcano arrays serve as high‐performance substrates for surface enhancement Raman spectroscopy (SERS) measurements. The experimental study shows that the structural features of the nanovolcano arrays, including concave nanobowls, nanopores, and their long‐range orders, all contribute to the observed strong SERS enhancement in a synergetic manner, which is further confirmed by the simulation results obtained using the finite‐difference time‐domain method. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
999.
1000.
张哲  胡晨  王学香  时龙兴 《电子器件》2004,27(4):705-709,718
传统的BIST结构中,由于LFSR产生大量的测试矢量在测试过程中消耗了大量的功耗。为了减少测试矢量的数目而不影响故障覆盖率,我们提出了一种新的基于双模式LFSR的低功耗BIST结构。首先介绍了功耗模型和延迟模型的基础知识,然后给出了用于生成双模式LFSR的矩阵,并介绍了解矩阵方程式的算法。随后说明了新的BIST结构和用于矢量分组的模拟退火算法。最后,基于Benchmark电路的实验证明这种结构可以在不降低故障覆盖率的同时减少70%的功耗。  相似文献   
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