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151.
Thermosonication (TS) of preheated (45 °C) milk (0.1%, 1.5% and 3.5% fat) for 10 min at an ultrasound frequency of 24 kHz allowed the preparation of yoghurts with rheological properties superior to those of control yoghurts produced from conventionally heated milk (90 °C for 10 min). Texture profile analysis and flow curves showed that yoghurts from the TS milks had stronger gel structures which displayed higher water-holding capacities (WHC) and lower syneresis. Based on averaged data from a sensory panel (n = 30), TS yoghurts showed superior texture and colour properties and samples with a fat content of 0.1% scored best in terms of overall acceptability. Retentions of water-soluble (thiamine and riboflavin) and fat-soluble (retinol and tocopherol) vitamins were similar in TS and conventionally prepared yoghurts.  相似文献   
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153.
A versatile biopolymer platform for advancing nanodiamonds (NDs) as unique magnetooptic materials for biomedical applications is presented here. Precision biopolymer coatings are designed by chemical reprogramming the functionalities of serum albumin via a straightforward synthesis protocol. Such biopolymers offer high biocompatibility and precise modification with various functional entities due to the large number of available reactive amino acid residues. Premodification of these biopolymers provides a convenient approach to customized surface functionalization of NDs. As an example, the anticancer drug doxorubicin (DOX) is conjugated to the biopolymer with high reproducibility and full characterization. The biopolymer‐coated NDs reveal excellent colloidal stabilities in all physiological media tested, even after loading with high numbers of hydrophobic DOX. The intracellular distribution of NDs and DOX is analyzed in living cells by recording the fluorescence spectra in different cellular compartments, which proves efficient intracellular release of DOX from the carrier. Studies in vitro as well as in a chick tumor xenograft model reveal efficient antitumor effects. The facile and versatile biopolymer coating strategy reported herein will greatly accelerate the availability of customized NDs with reliable and reproducible features to exploit their great potential in single molecular bioimaging, in vivo biosensing, and high resolution quantum optics.  相似文献   
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155.
Synchrotron radiation techniques represent powerful tools to characterize materials down to the nanometer level. This paper presents a survey of the state‐of‐the‐art synchrotron‐based techniques which are particularly well‐suited for investigating materials properties. Complementary X‐ray absorption techniques such as extended X‐ray absorption fine structure (EXAFS), X‐ray magnetic circular dichroism (XMCD), photoemission electron microscopy (PEEM) are used to address the individual local atomic structure and magnetic moments in Fe–Cr model systems. The formation of atomic clusters/precipitates in such systems is also investigated by means of scanning transmission X‐ray microscopy (STXM). Such advanced analytical techniques can not only offer valuable structural and magnetic information on such systems, they can also serve for validating computational calculations performed at different time and length scales which can help improve materials lifetime predictions.  相似文献   
156.
A large part of software development these days deals with building so-called Web applications. Many of these applications are data-base-powered and exhibit a page layout and navigational structure that is close to the class structure of the entities being managed by the system. Also, there is often only limited application-specific business logic. This makes the usual three-tier architectural approach unappealing, because it results in a lot of unnecessary overhead. One possible solution to this problem is the use of model-driven architecture (MDA). A simple platform-independent domain model describing only the entity structure of interest could be transformed into a platform-specific model that incorporates a persistence mechanism and a user interface. Yet, this raises a number of additional problems caused by the one-way, multi-transformational nature of the MDA process. To cope with these problems, the authors propose the notion of a model-driven runtime (MDR) environment that is able to execute a platform-independent model for a specific purpose instead of transforming it. The paper explains the concepts of an MDR that interprets OCL-annotated class diagrams and state machines to realize Web applications. It shows the authors' implementation of the approach, the Infolayer system, which is already used by a number of applications. Experiences from these applications are described, and the approach is compared to others. This is an extended and revised version of a paper originally presented at the UML 2003 conference in San Francisco [1]. The second author has been supported by the German Federal Ministry of Education and Research (BMBF), grant 08NM098.  相似文献   
157.
Schema matching is an important step in database integration. It identifies elements in two or more databases that have the same meaning. A multitude of schema matching methods have been proposed, but little is known about how humans assign meaning to database elements or assess the similarity of meaning of database elements. This paper presents an initial experimental study based on five theories of meaning that compares the effects of seven factors on the perceived similarity of database elements. Implications for schema matching research are discussed and guidance for future research is offered.  相似文献   
158.
Although high intensity ultrasound (US) has the potential to simultaneously homogenize milk and to reduce its microbial load, the treatment may give rise to off-odours under certain conditions. This study is a preliminary examination of the chemical nature and possible genesis of volatiles implicated in this process. An ultrasonic processor fitted with an ultrasonic horn (diameter 22 mm) set at a maximum acoustic power output of 400 W (frequency 24 kHz) was used to sonicate 200 mL milk samples (1.5% fat). Solid phase microextraction headspace analysis was used in combination with gas chromatography/mass spectrometry to analyse the products evolved in the process during treatment times of 2.5, 5, 10, 15 and 20 min. Volatiles generated by US treatment, which included benzene, toluene, 1,3–butadiene, 5-methyl-1,3-cyclopentadiene and a series of aliphatic 1-alkenes, were predominantly hydrocarbons and believed to be of pyrolytic origin, possibly generated by high localized temperatures associated with cavitation phenomena.  相似文献   
159.
Das S  Appenzeller J 《Nano letters》2011,11(9):4003-4007
Science and technology in the electronics area have always been driven by the development of materials with unique properties and their integration into novel device concepts with the ultimate goal to enable new functionalities in innovative circuit architectures. In particular, a shift in paradigm requires a synergistic approach that combines materials, devices and circuit aspects simultaneously. Here we report the experimental implementation of a novel nonvolatile memory cell that combines silicon nanowires with an organic ferroelectric polymer-PVDF-TrFE-into a new ferroelectric transistor architecture. Our new cell, the ferroelectric transistor random access memory (FeTRAM) exhibits similarities with state-of-the-art ferroelectric random access memories (FeRAMs) in that it utilizes a ferroelectric material to store information in a nonvolatile (NV) fashion but with the added advantage of allowing for nondestructive readout. This nondestructive readout is a result of information being stored in our cell using a ferroelectric transistor instead of a capacitor-the scheme commonly employed in conventional FeRAMs.  相似文献   
160.
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