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排序方式: 共有675条查询结果,搜索用时 31 毫秒
1.
To enhance chemical stability and suppress of aggregation of magnetite nanoparticles (MNPs), which are used as a support for thermoresponsive copolymer immobilization, silica coating of the MNPs is applied via the electrooxidation method. Although the resulting silica coated-MNPs also formed aggregates, the size distribution of the aggregate shifted to smaller size range. Because of that, the surface area available for copolymer immobilization increased approximately 6.7 times at maximum as compared with that of the uncoated MNPs. It contributed to the increase of the amount of the immobilized copolymer on the silica-coated MNPs, which is approximately four times larger than that on the uncoated MNPs. Fe3O4 dissolution test confirmed enhancement of chemical stability of MNPs. The thermoresponsive copolymer immobilized on the silica-coated MNPs shows the ability to recycle Cu(II) ion from Cu(II) containing solution by changing temperature with significantly shorter time than those in other thermoresponsive adsorbents in gel form. 相似文献
2.
A Synthetic Transcriptional Activator of Genes Associated with the Retina in Human Dermal Fibroblasts
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3.
Akiko Suzuki Mina Minamide Chihiro Iwaya Kenichi Ogata Junichi Iwata 《International journal of molecular sciences》2020,21(23)
Carbohydrates, fats, and proteins are the underlying energy sources for animals and are catabolized through specific biochemical cascades involving numerous enzymes. The catabolites and metabolites in these metabolic pathways are crucial for many cellular functions; therefore, an imbalance and/or dysregulation of these pathways causes cellular dysfunction, resulting in various metabolic diseases. Bone, a highly mineralized organ that serves as a skeleton of the body, undergoes continuous active turnover, which is required for the maintenance of healthy bony components through the deposition and resorption of bone matrix and minerals. This highly coordinated event is regulated throughout life by bone cells such as osteoblasts, osteoclasts, and osteocytes, and requires synchronized activities from different metabolic pathways. Here, we aim to provide a comprehensive review of the cellular metabolism involved in bone development and homeostasis, as revealed by mouse genetic studies. 相似文献
4.
5.
N. Karasawa H. Kakehata K. Mishina J. Yamamoto S. Kobayashi 《Photonics Technology Letters, IEEE》2005,17(1):31-33
Using a cross-correlation frequency-resolved optical gating apparatus, the phases and amplitudes of ultrabroad-band optical pulses from a taper fiber have been measured for various input pulse peak powers. The measured waveforms have been compared with calculated waveforms using a finite-difference in the frequency domain method, in which no envelope approximations were used and the variation of the taper shape was taken into account. Excellent agreement between the measured and the calculated waveforms was obtained when the additional dispersion of a normal fiber and an objective was considered. 相似文献
6.
High performance liquid chromatographic separation of a series of mono-, di- and trihydroxylated 5β-cholanic acids which differ
only in position and configuration of hydroxyl groups at positions C-3, C-7 and/or C-12, is reported. The C-24 free acids
were derivatized to four different classes of UV-sensitive esters, i.e.,p-bromophenacyl (BP),m-methoxyphenacyl (MP), 4-nitrophthalimidemethyl (NPM) and 9-anthrylmethyl (AM) esters, and chromatographed on two, variants
of C18 reversed-phase columns (Nova-Pak C18 and Zorbax ODS) with methanol-water systems as mobile phase. Separation efficiency and elution order of some isomeric pairs
were influenced by both the structure of the C-24 ester groups and the nature of the columns used. Excellent chromatographic
properties were found for those derivatives, particularly for the NPM esters. 相似文献
7.
Teruya Tanaka Junichi. H. Kaneko Yoshimi Kasugai Masaki Katagiri Hiroshi Takeuchi Takeo Nishitani Toshiyuki Iida 《Diamond and Related Materials》2005,14(11-12):2031
Radiation tolerance of a type IIa synthetic diamond detector was examined from irradiation of mono-energetic 14 MeV neutrons. Measurements of I–V (current–voltage) characteristics and energy spectrum for 5.486 MeV alpha particles were performed after neutron irradiation. In the I–V characteristics measurement, enhancement of rectification was observed after neutron irradiation of up to 2.0 × 1012 n/cm2. Concurrently with the enhancement of rectification, significant decrease in signal amplitude was observed in energy spectrum measurement for alpha particles. It is considered that these changes were due to increase in the concentration of defects acting as shallow energy levels in the forbidden band. For neutron irradiation of higher than 1.6 × 1013 n/cm2, weakening of the rectification characteristics and recovery of the signal amplitude were observed. These changes imply that deep energy levels, which were also considered to be introduced by defects, were dominant and weakened the effects of the shallow energy levels. Increase in the concentration of the deep trapping levels resulted in gradual decrease of the signal amplitude and degradation in the energy resolution. The peak for the alpha particles was obtained up to 5.5 × 1013 n/cm2. 相似文献
8.
Land mobile radio systems such as car telephones and handy personal terminals used outdoors have enjoyed a remarkable evolution. To design reliable mobile radio systems, however, it is vital to have a good understanding of the impact of wave propagation characteristics on digital transmission quality in a wide variety of mobile radio environments. A very simple but general scheme for calculating irreducible bit error rate (BER) (namely, BER floor) due to intersymbol interference in frequency-selective Nakagami-Rice fading environments has been developed. The scheme, which we call the equivalent transmission-path model, plays a role in connecting wave propagation with digital transmission characteristics in a general manner. Through computer simulations assuming various types of delay profiles, we first identify key parameters of Nakagami-Rice fading dominating principally the occurrence of irreducible errors and we develop a simple method for the calculation of irreducible BER utilizing the nature or the key parameters. Then we examine the accuracy of the scheme for various types of phase-shift keying (PSK) transmission systems. Finally, based on the scheme, we show calculation examples of BER floor characteristics in line-of-sight fading environments 相似文献
9.
Owing to limitations of frequency resources, advanced sensor array processing techniques are needed in a growing wireless wideband communications market. A beamspace wideband processing technique is proposed and is shown to reduce both signal to interference and SNR ratios. Performances for different array processing algorithms, flexibility and complexity cost are thus improved 相似文献
10.
Pouria Pirzadeh Junichi Tatemura Oliver Po Hakan Hac?gümü? 《Journal of Grid Computing》2012,10(1):109-132
Recently there has been a considerable increase in the number of different Key-Value stores, for supporting data storage and
applications on the cloud environment. While all these solutions try to offer highly available and scalable services on the
cloud, they are significantly different with each other in terms of the architecture and types of the applications, they try
to support. Considering three widely-used such systems: Cassandra, HBase and Voldemort; in this paper we compare them in terms
of their support for different types of query workloads. We are mainly focused on the range queries. Unlike HBase and Cassandra
that have built-in support for range queries, Voldemort does not support this type of queries via its available API. For this
matter, practical techniques are presented on top of Voldemort to support range queries. Our performance evaluation is based
on mixed query workloads, in the sense that they contain a combination of short and long range queries, beside other types
of typical queries on key-value stores such as lookup and update. We show that there are trade-offs in the performance of
the selected system and scheme, and the types of the query workloads that can be processed efficiently. 相似文献