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101.
Surface modification of poly(ethylene terephthalate) by plasma polymerization of poly(ethylene glycol) 总被引:2,自引:0,他引:2
Sakthi Kumar D Fujioka M Asano K Shoji A Jayakrishnan A Yoshida Y 《Journal of materials science. Materials in medicine》2007,18(9):1831-1835
Poly(ethylene glycol) (PEG) was ‘polymerized’ onto poly(ethylene terephthalate) (PET) surface by radio frequency (RF) plasma
polymerization of PEG (average molecular weight 200 Da) at a monomer vapour partial pressure of 10 Pa. Thin films strongly
adherent onto PET could be produced by this method. The modified surface was characterized by infra red (IR) spectroscopy,
scanning electron microscopy (SEM), atomic force microscopy (AFM), cross-cut test, contact angle measurements and static platelet
adhesion studies. The modified surface, believed to be extensively cross-linked, however showed all the chemical characteristics
of PEG. The surface was found to be highly hydrophilic as evidenced by an interfacial free energy of about 0.7 dynes/cm. AFM
studies showed that the surface of the modified PET became smooth by the plasma polymerized deposition. Static platelet adhesion
studies using platelet rich plasma (PRP) showed considerably reduced adhesion of platelets onto the modified surface by SEM.
Plasma ‘polymerization’ of a polymer such as PEG onto substrates may be a novel and interesting strategy to prepare PEG-like
surfaces on a variety of substrates since the technique allows the formation of thin, pin-hole free, strongly adherent films
on a variety of substrates. 相似文献
102.
Nakazawa M Kosugi T Nagatsuka H Maezawa A Nakamura K Ueha S 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2007,54(10):2165-2174
Ultrasonic transducers using polyurea piezoelectric thin film are studied in this paper. Aromatic polyurea thin films, prepared by vapor deposition polymerization, have useful characteristics for use as an ultrasonic transducer. This paper presents the fabrication and experimental evaluation of ultrasonic transducers formed using polyurea films. First, the vapor deposition polymerization process using two monomers is briefly reviewed, and the temperature conditions for higher piezoelectric constants are explored. Second, in order to test the fundamental characteristics of this material as a high-frequency, ultrasonic transducer, a polyurea film of 2.5 microm thickness was deposited on a silicon substrate. In the pulse/echo experiment results, a resonant frequency of about 100 MHz was observed. Third, we fabricated a concave point focus transducer and a cylindrical line focus transducer. To examine the performances of the focus transducers, two-dimensional images of a coin and V(z) curve measurements for an aluminum surface were demonstrated. 相似文献
103.
Murakawa K Fukunaga K Tanouchi M Hosokawa M Hossain Z Takahashi K 《Journal of oleo science》2007,56(4):179-188
Mushroom (Agaricus blazei Murill) extract has been reported to possess antitumor effects through immune activation. Here, we investigated the beneficial effects of combining A. blazei extract with marine phospholipids in comparison to A. blazei extract alone on myeloma sp2 tumor suppression when orally administrated. The experimental groups designed for sp2 tumor bearing BALB/c nu/nu mice were drinks of: (1)control; (2)1.0 mg/mL squid phospholipid liposome alone; (3)0.5 mg/mL A. blazei Murill water extract alone; (4)1.0 mg/mL squid phospholipid liposome with 0.5 mg/mL A. blazei Murill water extract in the form of those simple mixture; and (5)1.0 mg/mL squid phospholipid liposome with 0.5 mg/mL A. blazei Murill water extract partially encapsulated. Orally administrated volumes amounted to approximately 5 mL per day per mouse for all groups. A. blazei Murill water extract alone and squid phospholipid alone served groups show moderate tumor suppression with total administrations of approximately 105 mg/mouse for squid phospholipid through out the experimental term. When both A. blazei Murill water extract and squid phospholipid were administrated simultaneously in a simple mixture form, promotional effect on cancer tumor suppression was observed. And when A. blazei Murill water extract was partially encapsulated in the squid phospholipid liposomes with total administrations being 105 mg/mouse for squid phospholipid, effect on cancer tumor suppression was more pronounced. Though there was no statistically significant difference in tumor sizes between the simple mixture form administrated group i.e. group (4) and the partially encapsulated form administrated group i.e. group (5), the tumor vanished mouse was seen in the partially encapsulated form administrated group. Thus it was concluded that combinational administration of the A. blazei Murill water extract and the marine phospholipid may be useful in myeloma sp2 therapy. 相似文献
104.
Taga A Nishi T Honda Y Sato A Terashima H Suzuki K Kodama S Boki K 《Journal of oleo science》2007,56(8):429-434
Recently environmental control is regarded as important for good human health conditions, and toxic substances, including carcinogens and endocrine disruptors should be eliminated from our living environment. Hence easy quantitative methods are expected for a high level of environmental control. Our previous paper describes an easy quantitative analysis of nitrosamines (NAs) by capillary electrophoresis with an untreated fused silica capillary installed in an ordinary apparatus. In this paper, utilizing a novel type capillary column having sulfonated inner wall was investigated for improvements of separation performance and reproducibility. A sulfonated capillary causes fast and stabile electroosmotic flow because its inner wall is strongly negative charged. On a performance comparison of a sulfonated capillary with an untreated fused silica, analysis time reduction of c.a. forty percent was achieved, and relative standard deviations of migration times and peak responses were less than one third. In addition sample concentrations giving detection and quantitation limits were also reduced to a half. 相似文献
105.
Incremental Focus of Attention for Robust Vision-Based Tracking 总被引:3,自引:0,他引:3
We present the Incremental Focus of Attention (IFA) architecture for robust, adaptive, real-time motion tracking. IFA systems combine several visual search and vision-based tracking algorithms into a layered hierarchy. The architecture controls the transitions between layers and executes algorithms appropriate to the visual environment at hand: When conditions are good, tracking is accurate and precise; as conditions deteriorate, more robust, yet less accurate algorithms take over; when tracking is lost altogether, layers cooperate to perform a rapid search for the target and continue tracking.Implemented IFA systems are extremely robust to most common types of temporary visual disturbances. They resist minor visual perturbances and recover quickly after full occlusions, illumination changes, major distractions, and target disappearances. Analysis of the algorithm's recovery times are supported by simulation results and experiments on real data. In particular, examples show that recovery times after lost tracking depend primarily on the number of objects visually similar to the target in the field of view. 相似文献
106.
讨论了由三个氘原子组成的氘团簇离子束与独立氘离子束在轰击固体靶时,在原子过程呼D-D核聚变过程中体现出的差别。对氘团簇与固体靶相互作用的机理进行了分析。 相似文献
107.
Toshiyuki Nagata Kentaro Minami Masatatsu Yamamoto Tsubasa Hiraki Masashi Idogawa Katsumi Fujimoto Shun Kageyama Kazuhiro Tabata Kohichi Kawahara Kazuhiro Ueda Ryuji Ikeda Yukio Kato Masaaki Komatsu Akihide Tanimoto Tatsuhiko Furukawa Masami Sato 《International journal of molecular sciences》2021,22(21)
108.
109.
Jun Nishihira Maremi Sato-Ueshima Kentaro Kitadate Koji Wakame Hajime Fujii 《Journal of Functional Foods》2009,1(4):341-348
The effect of low-molecular-weight polyphenols extracted from lychee (Oligonol) on metabolic syndrome characterized by abdominal obesity was examined. We performed a clinical trial for Oligonol conducted by randomized double-blind, placebo-controlled study. Eighteen (male, 14; female, 4) adult volunteers with abdominal circumference over 85 cm were enrolled and divided into two groups, Oligonol and placebo groups. All subjects took two capsules of Oligonol (50 mg/capsule) or placebo twice a day for 10 weeks. Physical and haematological examinations as well as a CT scan of the abdomen were carried out, before (control) and 10 weeks after Oligonol intake. Clinical parameters of body weight, abdominal circumference and visceral fat volume were significantly decreased in the Oligonol group compared to the control. Insulin resistance was improved by Oligonol in conjunction with elevation of serum adiponectin. These results suggest that Oligonol ameliorates metabolic syndrome by reducing visceral fat obesity. 相似文献
110.
The techniques for fabricating a hollow optical fiber with an inner silver layer and a cyclic olefin polymer (COP) layer have been improved to reduce the surface roughness of these two layers. The loss spectrum was thereby drastically reduced over a wide wavelength range, from visible to near infrared. Optimization of the COP layer thickness resulted in low loss simultaneously at several key laser wavelengths. Infrared hollow fiber with low loss was developed for Er:YAG and Nd:YAG lasers. It can also deliver green and red pilot beams with low loss. Use of this fiber in therapeutic and pilot lasers should prove useful for research and development in laser medicine. 相似文献