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71.
Silica films with a single-crystalline mesoporous structure 总被引:1,自引:0,他引:1
Miyata H Suzuki T Fukuoka A Sawada T Watanabe M Noma T Takada K Mukaide T Kuroda K 《Nature materials》2004,3(9):651-656
Films of mesoporous materials attract broad interest because of their wide applicability in the fields of optics and electronics. Although many of these films have a regular local porous structure, the structural regularity has not been used practically yet because of difficulties in its control on macroscopic scales. Here, we demonstrate the preparation of mesoporous silica films whose porous structure can be described as a single crystal, that is, a long-range order of cage-like pores is maintained over centimetre scales. These films have a three-dimensional hexagonal (space group P6(3)/mmc) porous structure, and the in-plane arrangement of the pores is strictly controlled by a polymeric substrate surface that has been treated by rubbing. This new class of single-crystalline films with mesoscopic periodic structure is a significant breakthrough in bottom-up nanotechnology, and could lead to novel devices, for example, optics in a soft X-ray region, and quantum electronics. 相似文献
72.
The fluorogenic derivatization reagents with a positive charge, 4-(dimethylaminoethylaminosulfonyl)-7-chloro-2,1,3-benzoxadiazole (DAABD-Cl) and 7-chloro-2,1,3-benzoxadiazole-4-sulfonylaminoethyltrimethylammonium chloride (TAABD-Cl), are proposed for use in proteomics studies. Following derivatization of protein mixtures with these reagents, a series of standard processes of isolation, digestion, and identification of the proteins were performed utilizing high-performance liquid chromatography-fluorescence detection and tandem mass spectrometry with the probability-based protein identification algorithm. Both DAABD and TAABD derivatives were detected fluorometrically at the femtomole level and showed more than 100-fold improvement in sensitivity compared to the underivatized original compounds with an electrospray ionization ion trap mass spectrometer analysis. The modification of the MASCOT database search system memorized with the fragment information of a DAABD-attached Cys residue allowed the identification of the proteolytic peptide fragments of the derivatized bovine serum albumin (BSA) with an estimated 38% sequence coverage of BSA. Utilizing DAABD-Cl as a derivatization reagent, identification of several proteins was also possible in a soluble extract of Caenorhabditis elegans (10 microg of protein). Consequently, for identification of proteins in the complex matrixes of proteins, DAABD-Cl could be a more appropriate reagent than ammonium 7-fluoro-2,1,3-benzoxadiazole-4-sulfonate as reported previously. 相似文献
73.
Suzuki I Yamada K Yamakawa T Hashiba M Akazawa K 《Computer methods and programs in biomedicine》2003,70(3):253-258
We developed a low cost, user-friendly multimedia delivery system, to provide medical lectures saved as multimedia contents to persons engaged in medicine. This system was created using the RealSystem package with the TCP/IP network. Users can review lectures and medical meeting presentations with video and audio through the Internet, whenever convenient. Each medical source of video and slide has been clearly displayed on a screen. Members of medical associations or medical students can easily review the most interesting parts of these files. This system is being used efficiently in distance learning and aids the diffusion of the latest information and technology to busy physicians and medical students. 相似文献
74.
A simple and rapid method for the simultaneous determination of five penicillins (ampicillin, penicillin G, penicillin V, oxacillin and cloxacillin) in muscle, liver and kidney tissues using high-performance liquid chromatography-electrospray tandem mass spectrometry (LC-ESI-MS/MS) was developed. Mass spectral acquisition was done in the negative ion mode by applying selected reaction monitoring (SRM). The five penicillins were extracted with water, and the extracted solution was cleaned up on a C18 cartridge. Phenethicillin was added as an internal standard, and the extract was diluted with water for injection into the LC-ESI-MS/MS. The recoveries of the five penicillins were in the range of 77.3-99.8% from muscle, liver and kidney fortified at 10-250 ng/g. The detection limits for ampicillin were 6 ng/g in muscle and kidney and 15 ng/g in liver. For penicillin G and penicillin V, the detection limits were 2 ng/g in muscle and kidney and 5 ng/g in liver. For oxacillin and cloxacillin, the detection limits were 4 ng/g in muscle and kidney and 10 ng/g in liver. Twenty-three muscle, fourteen liver and twenty-two kidney samples from the markets were analyzed by this method. No penicillins were detected in any sample. 相似文献
75.
The purpose of this research is a quantitative analysis of movement patterns of dance,which cannot be analyzed with a motion capture system alone,using simultaneous measurement of body motion and biophysical information.In this research,two kinds of same leg movement are captured by simultaneous measurement;one is a leg movement with given strength,the other is a leg movement without strength on condition of basic experiment using optical motion capture and electromyography (EMG) equipment in order to quantitatively analyze characteristics of leg movement.Also,we measured the motion of the traditional Japanese dance using the constructed system.We can visualize leg movement of Japanese dance by displaying a 3D CG character animation with motion data and EMG data.In addition,we expect that our research will help dancers and researchers on dance through giving new information on dance movement which cannot be analyzed with only motion capture. 相似文献
76.
Miyuki Hayashi Hirokage Yamada Naozumi Nabeshima Kazuhiro Nagata 《International Journal of Thermophysics》2007,28(1):83-96
The temperature dependences of the velocity of sound in liquid Pb, Sn, Ge, and Si have been measured by means of the pulse
transmission technique over temperature ranges of 610–1078 K, 608–1463 K, 1215–1443 K, and 1723–1888 K, respectively. In both
liquid Pb and Sn, the velocities of sound decrease linearly with increasing temperature, which is the same temperature dependence
as shown in many other liquid metals. On the other hand, the velocities of sound in liquid Ge and Si exhibit anomalous temperature
dependences. In Ge, the velocity of sound has a distinct maximum around 1280 K and decreases linearly at higher temperatures.
In Si, the velocity of sound increases monotonically with increasing temperature in the temperature range investigated. It
is considered that these results predict that the coordination numbers of liquid Ge and Si increase with increasing temperature. 相似文献
77.
Water-repellent surfaces were fabricated on blend sheets of poly(l-lactic acid)/poly(butylene succinate) with various blending ratios by the successive processing; (1) plasma etching, followed by (2) the hydrophobic plasma polymer coating. Rough morphology was formed effectively on the mosaic structured surface of blend sheets via the oxidative etching, and advanced water repellency was achieved after the thin membrane coating was synthesized with a hydrophobic plasma polymer coating by use of hexamethyldisiloxane or hexamethyldisilazane. High water repellency is expressed through the columnar hair-like structured model, where the air-water surface interaction in the voids is taken into account. 相似文献
78.
Thermoelectric Detection of Multi‐Subband Density of States in Semiconducting and Metallic Single‐Walled Carbon Nanotubes 下载免费PDF全文
79.
This paper proposed two types of speed sensorless converters that can control rotational speed and electric power. One is based on a slip frequency control system. The other is based on a vector control system. The rotational speed of the wind turbine is estimated with the phase voltage and phase current of the induction generator by the adaptive rotor flux observer. The estimated wind turbine rotational speed ωrest is used as the feedback of the speed control loop in the converter control system. Also, the estimated rotor flux ?2dest is used for the vector control. The simulation results confirm that both of them perform satisfactorily under the speed sensorless operation. The method based on the vector control system generates more electrical energy than does the method based on the slip frequency control system. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 159(4): 62–75, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20323 相似文献
80.
A new method for on-substrate fine positioning of microscale/mesoscale discrete components is presented, where component positions are finely adjusted using microlinear sliders and fixtures on the substrate. Each microlinear slider is actuated by vibratory impacts exerted by two pairs of microcantilever impacters. These microcantilever impacters are selectively resonated by shaking the entire substrate with a piezoelectric vibrator, requiring no need for built-in driving mechanisms such as electrostatic comb actuators, as reported previously. This selective resonance of the microcantilever impacters via an external vibration energy field provides with a very simple means of controlling forward and backward motion of the microlinear slider, facilitating assembly and disassembly of a microcomponent on a substrate. An analytical model of the device is derived in order to obtain, through the simulated annealing algorithm, an optimal design, which maximizes translation speed of the linear slider at desired external input frequencies. Prototypes of the externally resonated linear microvibromotor are fabricated using the three-layer polysilicon surface micromachining process provided by the Microelectronics Center of North Carolina, Research Triangle Park, NC, multiuser microelectromechanical processes service. These prototypes are tested for forward and backward motion via external vibration applied by an piezoelectric flexure vibrator, as well as the horizontal positioning and release of 500-μm-square polysilicon chips against a reference fixture element anchored to the substrate 相似文献