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排序方式: 共有253条查询结果,搜索用时 31 毫秒
121.
An emulsion gel adsorbent which was a polymeric hydrogel containing randomly distributed oil microdroplets of an extractant was developed for improved metal adsorption in our previous study. This study focuses on the preparation of monodisperse, millimeter- or sub-millimeter-sized emulsion gel beads, for which a novel production method combining sedimentation polymerization and two-fluid atomization is proposed. The method involves the drop-wise addition of a pre-gel oil-in-water emulsion solution into a silicone oil through a nozzle, with nitrogen gas flow, and the subsequent free-radical polymerization of the pre-gel droplets during their descent. A novel type of emulsion gel bead composed of a poly(ethylene glycol) methyl ether acrylate hydrogel and di-n-hexylsulfide as an extractant was developed. The size of the emulsion gel beads was controlled by adjusting the gas flow rate. The emulsion gel beads successfully adsorbed Pd(II) ions that were used as a model metal. 相似文献
122.
Municipal solid wastes (MSW) collected in Kyoto city were carefully separated, and the waste-type proportion in MSW was surveyed. A hydrogen/methane fermentation batch experiment was conducted under thermophilic condition using twenty different types of MSW components. Biodegradable wastes in the MSW almost consist of vegetable kitchen waste, and the characteristics of hydrogen and methane fermentation of MSW were similar to that of vegetable kitchen waste. Hydrogen production per g VS added was considerably positively correlated with easily degradable carbohydrates concentration and negatively correlated with cellulosic materials concentration. The various feedstocks could be classified into four groups according to nutrient composition (protein, fat, cellulosic materials and easily degradable carbohydrates), and the feedstocks belonging to carbohydrates rich group showed higher hydrogen yields than the other feedstocks. Rough hydrogen yield could be easily predicted by concentration of easily degradable carbohydrates. 相似文献
123.
Kazuhiro Kajikawa Hirotsugu Kuga Takuro Inoue Kazuki Watanabe Yushi Uchida Taketsune Nakamura Tsuyoshi Wakuda Kazuhide Tanaka 《Journal of Superconductivity and Novel Magnetism》2013,26(5):1537-1541
An electric pump composed of an MgB2 motor is combined with a superconducting level sensor using a thin CuNi-sheathed MgB2 wire to demonstrate the transfer of liquid helium. An impeller is attached to the lower end of a rotating shaft of the MgB2 motor and covered with an outer casing to form a kind of centrifugal pump. After that, the MgB2 motor with the impeller is located vertically inside a cryostat with an infill of the liquid helium. Another glass Dewar vessel is also prepared to receive the liquid helium transferred from the cryostat containing the MgB2 motor. The MgB2 sensor is used not only to detect the level of the liquid helium but also to control the electric pump on the basis of its pre-estimated calibration curve. By using the assembled pump system, the liquid helium is successfully transferred from the cryostat to the glass Dewar vessel via a transfer tube. The transfers of liquid hydrogen with the identical pump system will be carried out in the near future. 相似文献
124.
125.
We report a local crystal structure analysis with a high precision of several picometers on the basis of scanning transmission electron microscopy (STEM). Advanced annular dark-field (ADF) imaging has been demonstrated using software-based experimental and data-processing techniques, such as the improvement of signal-to-noise ratio, the reduction of image distortion, the quantification of experimental parameters (e.g., thickness and defocus) and the resolution enhancement by maximum-entropy deconvolution. The accuracy in the atom position measurement depends on the validity of the incoherent imaging approximation, in which an ADF image is described as the convolution between the incident probe profile and scattering objects. Although the qualitative interpretation of ADF image contrast is possible for a wide range of specimen thicknesses, the direct observation of a crystal structure with deep-sub-angstrom accuracy requires a thin specimen (e.g., 10 nm), as well as observation of the structure image by conventional high-resolution transmission electron microscopy. 相似文献
126.
S. Ozawa N. Takenaga T. Koda T. Hibiya H. Kobatake H. Fukuyama M. Adachi M. Watanabe S. Awaji 《Materials Science and Engineering: A》2008,495(1-2):50
When a static magnetic field was applied to a Si droplet levitated by an electromagnetic force, only one peak was observed to remain in the frequency spectrum. It was the objective of this work to clarify whether this peak can be assigned to the m = ± 2 oscillation or to the rotation of the droplet. By analyzing the behavior of the deflection angle of the droplet in a top view, we conclude that this peak is not due to the surface oscillation of the droplet but to the droplet rotation. 相似文献
127.
A Watanabe T Tominaga H Shutoh H Hayashi J Tsuji A Koda H Nagai Y Kumazawa H Shimada 《Canadian Metallurgical Quarterly》1997,28(2):305-309
Over a period of 15 months, 178 consecutive attempts at supraclavicular catheterization of the subclavian veins were performed by the same operator. There were 42 additional central lines inserted during this period, which were placed via other methods as specified by the attending physicians. Results of the supraclavicular approach are presented and are believed to be the largest reported series of supraclavicular line insertions by one operator. Forty-five of the supraclavicular lines were placed after failed attempts by other emergency room and surgical physicians. Five were inserted in patients that were in hypovolemic shock, and three were placed in morbidly obese patients weighing 800, 400, and 335 pounds. Of the 178 attempts, there was only one significant complication: a left-sided pneumothorax on the 21st attempt in an emphysematous patient. The vein was successfully accessed in 177 cases with only two instances of inability to thread the catheter and one instance of malposition. Overall, there was satisfactory placement in 97.8% of attempts with a significant complication rate of 0.56%. This paper intends to describe the details of subclavian venipuncture by the supraclavicular technique, and, because of the high degree of reliability and safety of this technique in experienced hands, to recommend it as an excellent alternative for central venous access --especially in difficult cases. 相似文献
128.
Changing transcription start sites in H-type alpha(1,2)fucosyltransferase gene (FUT1) during differentiation of the human erythroid lineage 总被引:1,自引:0,他引:1
1. Ligands of the various adenosine receptor subtypes modulate the production of pro-and anti-inflammatory cytokines. Here we evaluated the effect of adenosine and various ligands of the adenosine receptor subtypes (A1, A2, A3) on the chemokine macrophage inflammatory protein (MIP) 1alpha production in immunostimulated RAW macrophages in vitro. Furthermore, we studied whether a selected A3 adenosine receptor agonist inhibits MIP-1alpha production and affects the course of inflammation in collagen-induced arthritis. 2. In the cultured macrophages, the A3 receptor agonist N6-(3-iodobenzyl)-adenosine-5'-N-methyluronamide (IB-MECA), and, less potently, the A2 receptor agonist 2-p-(2-carboxyethyl) phenethylamino-5'-N-ethyl-carboxamidoadenosine (CGS; 1-200 micro) dose-dependently suppressed the production of MIP-1alpha. The selective A1 receptor agonist 2-chloro-N6-cyclopentyladenosine (CCPA, 1-200 microM) was ineffective, and adenosine was a weak inhibitor. The inhibition of MIP-1alpha production by the A3 and A2 agonist was associated with suppression of its steady-state mRNA levels. 3. Based on the in vitro data, we concluded that activation of A3, and to a lesser extent A2 adenosine receptors suppresses MIP-1alpha expression. Since IB-MECA was the most potent inhibitor of MIP-1alpha expression, we next investigated whether it affects the production of other pro-inflammatory mediators. We observed that IB-MECA (1-300 microM) inhibited, in a dose-dependent manner, the production of IL-12, IL-6, and, to a lesser extent, nitric oxide in the immunostimulated cultured macrophages. 4. Since MIP-alpha is a chemokine which enhances neutrophil recruitment into inflammatory sites, we investigated whether the A3 agonist IB-MECA affects the course of inflammation, MIP-alpha production and the degree of neutrophil recruitment in arthritis. In a model of collagen-induced arthritis in mice, IB-MECA (0.5 mg/kg/day) reduced the severity of joint inflammation. IB-MECA inhibited the formation of MIP-1alpha, IL-12 and nitrotyrosine (an indicator of reactive nitrogen species) in the paws, and suppressed neutrophil infiltration. 5. We conclude that adenosine receptor agonists, most notably the A3 agonist IB-MECA suppress the production of MIP-alpha, and exert anti-inflammatory effects. Therefore, stimulation of adenosine receptor subtypes A3 and A2 may be a strategy worthy of further evaluation for the abrogation of acute or chronic inflammatory disorders. 相似文献
129.
Tomihiro Kamiya Takuro Sakai Tsuyoshi Hamano Tamotsu Suda Toshio Hirao 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1997,130(1-4):285-288
A beam scanning and target profiling technique that provides precise and easy beam positioning on samples has been established for the light ion and heavy ion microbeam systems in TIARA of JAERI. The beam positioning accuracy in these systems was measured using nuclear track detectors, CR-39's. The beam positioning accuracy and indirect beam positioning technique in the heavy ion microbeam system enabled extremely low current microbeam to hit targeted virgin points in micro-structure semiconductor test samples for study of single event upset (SEU) transient current properties. This paper gives details of the beam scanning and target profiling system, and describes and discusses the experiments by using this system. 相似文献
130.
Shuichi Hashimoto Kazuo Samata Tatsuya Shoji Nobuyuki Taira Takuro Tomita Shigeki Matsuo 《Microporous and mesoporous materials》2009,117(1-2):220-227
We examined a method to refine a technique to prepare close-packed monolayers of cylindrical zeolite L crystals tethered on a substrate through covalent linkages, which was developed recently for popular use. We attempted to fabricate both vertical and horizontal–unidirectional alignments of the zeolite particles. The vertical alignment for centimeter scale large areas was achieved on a flat glass substrate by using flat-based zeolite crystals with an aspect ratio (length divided by width) of 1.1 while the crystals with an aspect ratio of 1.7 failed to align vertically. Thus the parameters important for successful alignment were determined. On the other hand, the unidirectional alignment in the horizontal packing structures was achieved by employing pregrooved substrates. We found that the relationship between the sizes of zeolite crystals and grooves is a crucial factor for the preparation of a close-packed structure. In this respect, our present preparation requires further improvements because it resulted in structures with many void spaces. Furthermore, we prepared the zeolite films loaded with unidirectionally aligned dyes to achieve optical functionalities. 相似文献