共查询到20条相似文献，搜索用时 31 毫秒
1.
Japanese officials are struggling to prevent the spread of mad cow disease. Japan's first case of mad cow disease was reported in September. The Agriculture Ministry (农业部) confirmed last month that a second cow was infected (感染). Japan is the only country in Asia where mad cow disease is known to have spread. 相似文献
2.
Particle image velocimetry （PIV） experimental results of wake flow structure of a NACA0012 airfoil with small attack angle mounted above water surface are introduced.The experiment was carried out in a small-scale wind-wave tunnel.The diameter of wind-wave tunnel test section is 1.7 m （long） × 0.4 m （width） × 0.4 m （height）.The flow fields around the airfoil were measured under four diffierent conditions by varying the distance between the airfoil and the water surface.The attack angle of the airfoil was kept 10- during the experiment.For each experimental condition,the time series of particle images was captured to calculate continuous evolution of the velocity fields.The velocity fields were ensemble averaged to get the statistic parameters such as mean velocity and vorticity.Typical instantaneous velocity fields for each case are introduced to show the basic flow structure of wind surface flow separation.The aerodynamic loads acting on the airfoil are analyzed qualitatively according to the mean vorticity distribution in the flow field based on the theory of vorticity aerodynamics.The results indicate that the flow structures and drag/lift force of the airfoil alter remarkably with the changing distance between the airfoil and water surface. 相似文献
3.
《海外英语》2002,(12)
A Japanese Imperial Navy subma rine, thought to be the first one sunk by a U. S. destroyer during the Dec. 7, 1941 attack on Pear Harbor, was discovered in an underwa ter military junkyard in the harbor.According to a press release from NOAA, the sub was one of five that was supposed to slip into Pearl Harbor and wait for the air attack from the Japanese. 相似文献
4.
This paper presents the results of an investigation to use arc-length mesh generation and finite volume TVD scheme to calculate Euler equations for predicting the effect of geometry parameters in reducing the drag force and improving the lift-drag ratio of grid fin in the supersonic flow regime. The effects of frame and web, whose cross section shape and thickness and spacing, on the aerodynamic character of the grid fin were studied. Calculations were made at Mach 2.5 and several angles of attack. The results were validated by comparing the computed aerodynamic coefficients against wind tunnel experimental data. Good agreement was found between computed and experimental results. The computed results suggest that parameters of the grid fin's frame have the greatest effect on the grid fin aerodynamic character, especially on its drag force. It was concluded proper choice of appropriate grid fin geometry parameters could reduce the drag force and improve the lift-drag ratios. 相似文献
5.
The purpose of this study was to explore what salient characteristics can be found in some university teachers＇ approaches to teaching in Finland, Japan and India, and in what ways university teachers in Finland, India and Japan use ICTs （information and communication technologies） in their own teaching. Furthermore, this study aimed to investigate what ICT applications these same teachers use in their teaching. The data were collected via an electronic survey and interviews. The participants （N=21） were university teachers from Finland （N=8）, Japan （N=I0） and India （N=3）. Their approaches to teaching were explored by applying the ATI （approaches to teaching inventory） and its modified version focusing on the use of ICTs in teaching. The study reported in this paper was a pilot study, thus the results are based on the limited number of respondents. The ATI and ATI ICT subscales and ICT inventory applied in this study have been confirmed to be valid. The university teachers in Japan and Finland differed in their approaches to teaching： The Finnish teachers scored higher on the CCSF （conceptual change orientated, student-focused） approach to teaching than the Japanese teachers, while the Japanese teachers scored higher on the ITTF （information transmitting, teacher-focused） approach to teaching. Two Indian teachers were classified as having a teacher-focused approach to teaching, while the third was classified as having a student-focused approach to teaching. The teachers＇ differences in their use of ICTs related more to their disciplinary status than to their cultural background. 相似文献
6.
A giant jellyfish has appeared in the Sea of Japan since mid-August 2002. It is more than 91cm in diameter and may weigh as much as 150kg. It was moving in the sea of Fukui prefecture in the central coast of Japan when it was found. 相似文献
7.
ZHENG Weioping 《美中教育评论》2008,5(9):60-63
The visit of Bertrand Russell to China during 1920 to 1921 was one of the most significant events in May Fourth Movement, and Russell pointed out that education was the most important thing for Chinese reconstruction. The author argues that we should interpret Russell＇s educational idea of China from a theoretic and practical point of view. The man in Chinese education is the key to the future of China. 相似文献
8.
A qualitative investigation of trainees＇ adjustment in Japan：A case study of trainees from Indonesia
In Japan, there is a residence status known as “the trainee”. This is the status for residents who undertake “activities to learn and acquire the technology, skills, or knowledge at public or private organizations in Japan”. With the introduction of the Industrial Training Program in 1993, trainees have been permitted to extend their stay in Japan for education and employment purposes up to a maximum of three years. This study aims to investigate the adjustment styles of trainees and to consider the changes in their attitudes toward Japan in the course of this adjustment. Six male Indonesian trainees （mean age=23.83） were invited to a semi-structured interview. They were employed at the same factory, involved in the manufacture of car components, and were trainees in their first-, second-, and third-years. The interview mainly focused on the trainees＇ Japanese language skills, the changes in their images of Japan or Japanese people, the communication between them and their Japanese colleagues, and the difficulties they encountered during their stay in Japan. The results revealed that there were clear differences between the first, second, and third trainees. As the trainees＇ Japanese language skills improved, their communication with the Japanese colleagues increased. Subsequently, they developed more positive images of Japan and Japanese people and hoped to have more informal communication with Japanese people. 相似文献
9.
The influence of water on protein conformation was investigated by simulating the molecular dynamics of a model protein lysozyme in different water systems.The lysozyme-water system with TIP3P water model and lysozyme-water cluster system with six-ring water model were evaluated.In addition,the radial distribution function of solvent around lysozyme was calculated.It is found that the distribution of water molecules around lysozyme is similar to that of water clusters.The analyses of dihedral angles and disulfide bonds of lysozyme show that the conformation of lysozyme is severely damaged in the lysozyme-water cluster system compared with that in the lysozyme-water system.This difference can be attributed to the formation of larger number of intermolecular hydrogen bonds between lysozyme and water cluster.It is in agreement with the analysis that water clusters can change the degree of denaturation in the process of heat denaturation of lysozyme. 相似文献
10.
The growth mechanism of spectinomycin dihydrochloride crystal in pure water and acetone-water mixture at different temperatures has been studied by induction period measurement. The induction period was measured visually. The solid-liquid interfacial tension was determined on the basis of classical homogenous nucleation theory and the surface entropy factor was calculated. It was shown that the interfacial tension and surface entropy factor increased with the increase of acetone concentration and the decrease of temperature. It was demonstrated that the growth mechanism of spectinomycin dihydrochloride crystal was controlled by birth and spread growth in pure water or in acetone-water mixture at high temperatures and turned from birth and spread growth tc spiral growth with the increase of acetone concentration in acetone-water mixture at low temperatures. 相似文献
11.
The hydrolysate of waste sludge was used as the feedstock of biodiesel production, and its technological feasibility was investigated. Waste sludge, collected from No.3 Municipal Wastewater Treatment Plant of Xi＇an, was hydrolyzed in two parallel reactors firstly. Yeast was added into one reactor for bioaugmentation, and the other reactor without yeast was used as a control. Then an acid-catalyzed in situ esterification process was carried out to convert the hydrolysate to biodiesel. The results of hydrolysis showed that the reactor bioaugmented with yeast could promote hydrolysis compared with the control one because of an obvious variance in total suspended solid （TSS）, volatile suspended solid （VSS） and soluble chemical oxygen demand （SCOD）. Furthermore, gas chromatography （GC） analysis exhibited that the total volatile fatty acid （VFA） was low in the hydrolysate of bioaugmentation reactor; however, its yield of the fatty acid methyl esters （FAMEs） by in situ esterification was obviously higher when compared with the control one. Therefore, it may be inferred that the hydrolysate of bioaugmentation was mainly inclined to longer-chain fatty acid rather than to VFA. Anyway, an FAMEs yield of 9.24% （wt%） from dried sludge was attained after the 12-d bioaugmentation hydrolysis and succedent esterification. This value was not only higher than that of the control one but also higher than that reported in previous literature. The above results illuminated that it was feasible to produce biodiesel from the bioaugmented hydrolysate of waste sludge. 相似文献
12.
A physical model of sinusoidal function was established. It is generalized that the force is directly proportional to a power function of the distance in a classical spring-oscillator system. The differential equation of the generalized model was given Simulations were conducted with different power values. The results show that the solution of the generalized equation is a periodic function. The expressions of the amplitude and the period （frequency） of the generalized equation were derived by the physical method. All the simulation results coincide with the calculation results of the derived expressions. A special function also was deduced and proven to be convergent in the theoretical analysis. The limit value of the special function also was derived. The generalized model can be used in solving a type of differential equation and to generate periodic waveforms. 相似文献
13.
1, 3：2, 4-di-p-methylbenzylidene-D-sorbitol （MDBS） is known to be an efficient sorbitol derivative gelator. Two new sorbitol derivative gelators were designed and synthesized in contrast to MDBS in order to study the gel properties of gelators with different structures. Their gelation behavior to 30 solvents was investigated. It was found that the gelation behavior was related to the molecular structure of gelators. Compared with MDBS, the gelator with more hydroxyl in the molecular structure could gel water and that with more aromatic ring could gel aromatic solvent. The fibrous and three-dimensional network of the gels was obtained by scanning electron microscopy （SEM）. Ultraviolet-visible （UV-Vis） spectroscopy revealed that π-π interaction was one of the main driving forces for the formation of gels. The π-π stacking of gelation increases with the number of aromatic rings in the molecular structure of gelator. Fourier transform infrared （FT-IR） spectroscopy revealed that the hydrogen bonding was also the main driving force for the formation of gels. The layered structure of the gels was studied by X-ray diffraction （XRD）. 相似文献
14.
《天津大学学报(英文版)》2015,(5)
Carotenoid isomerase(CRTISO)is a key enzyme that catalyzes the conversion of cis-lycopene to alltrans lycopene. In this study, we isolated and characterized the CRTISO gene from Lycium chinense(Lc CRTISO) for the first time. The open reading frame of Lc CRTISO was 1 815 bp encoding a protein of 604 amino acids with a molecular mass of 66.24 k Da. Amino acid sequence analysis revealed that the Lc CRTISO had a high level of similarity to other CRTISO. Phylogenetic analysis displayed that Lc CRTISO kept a closer relationship with the CRTISO of plants than with those of other species. Semi-quantitative PCR analysis indicated that Lc CRTISO gene was expressed in all tissues tested with the highest expression in maturing fruits. The overexpression of Lc CRTISO gene in transgenic tobacco resulted in an increase of total carotenoids in the leaves with β-carotene and lutein being the predominants. The results obtained here clearly suggested that the Lc CRTISO gene was a promising candidate for carotenoid production. 相似文献
15.
I In certain countries of the world, the king or queen is still considered to be a demi-god. The UK is not one of those countries. It＇s tree that up until the 17th ccntmy, the British king or queen was believed to rule by＇ divine fight＇, which was the idea that God chose the king or queen to rule and that he or she was therefore above the law. The idea that the monarch was above the law ended with the English Civil War, in which King Charles the First was imprisoned and then beheaded in 1649. 相似文献
16.
ZHANG Zhao-di XU Long-jun SHI Jian-hang XU Wei WU Wen-li LIU Cheng-lun 《重庆大学学报(英文版)》2015,14(3):79-86
The effects of the electro-deposition conditions on the crystal structure and the properties of electrolytic manganese dioxide(EMD) were investigated in this paper. The results show that EMD was γ-crystal, with sand-like rough interface. The optimal preparation conditions of EMD were 30 min deposition time, and p H=1.0 in Mn SO4-H2SO4 solution at 50 ?C. Surfactant(P1) was conducive to the uniform and stable surface of γ-Mn O2 film, the impedance and the specific surface area of the electrode modified with γ-Mn O2 increased by 21.4 times and 75.6 times, respectively. The redox reversibility and the resolution ratio of characteristic peaks with the modified electrode were significantly improved in the benzodiazepines electrochemical reaction. The achievement illustrated that the controllable synthesis of γ-Mn O2 film thickness was practical in electrochemical sensors, and the determination reliability of benzodiazepines was improved with γ-Mn O2 modified electrodes used in environment monitoring technology. 相似文献
17.
Kevin Rudd,Australia's prime minister,gave Japan an ultimatum yesterday to end its annual whale hunt in Antarctic waters. The warning to Japan,an important trade and security partner,was delivered on the eve of a visit by Katsuya Okada, the foreign minister. 相似文献
18.
The urea nitrogen adsorbent of complex type, which consists of chitosan coated dialdehyde cellulose （CDAC） and immobilized urease in gelatin membrane （IE）, was prepared. The cellulose, the dialdehyde cellulose （DAC） and the CDAC were characterized by scanning electronic microscope. The results indicate that the cellulose C2-C3 bond was broken under the oxidation of periodate and it was oxidated to DAC. The DAC was coated with chitosan and the CDAC was obtained. The adsorption of urea nitrogen onto the adsorbent in Na2HPO4-NaH2PO4 buffer solution was studied in batch system. The effects of the experiment parameters, including degree of oxidation of CDAC, initial urea nitrogen concentration, pH and temperature, on the adsorption capacity of urea nitrogen onto the adsorbent at CDAC/IE weight ratio 10：1 were investigated. The results indicate that these parameters affected significantly the adsorption capacity. The adsorption capacity of urea nitrogen onto the adsorbent was 36.7 mg/g at the degree of oxidation of CDAC 88%, initial urea nitrogen concentration 600 mg/L, pH 7.4 and temperature 37℃. 相似文献
19.
Microcystis aeruginosa FACHB 905 was used as a model organism to study the effects of small water clusters(SWCs) on the growth and microcystin(MC) production of toxic cyanobacteria.The results showed that SWCs were able to stimulate the growth of Microcystis aeruginosa,which resulted in increased cell numbers and higher specific growth rates after a 30-d treatment.The cell morphology indicated that Microcystis aeruginosa was in a better state of growth,and it was more prone to divide in SWCs than in normal water clusters.The SWCs treatment up-regulated MC synthesis and exudation in 10 d in Microcystis aeruginosa,and the intra-cellular MC content decreased after the 20th day subsequently.Moreover,the cellular photosynthetic pigment contents were temporarily stimulated by SWCs.A possible reason is that SWCs stimulated the growth by promoting photosynthesis,whereas the increased MC production was relevant to pigment contents. 相似文献
20.
Guo-dong SHAN Guo-qiang XU You-ming LI 《Journal of Zhejiang University. Science. B》2013,14(9):844-848
The objective of this study was to investigate the endosonographic appearance of gastric linitis plastica(GLP) and to study the usefulness of endoscopic ultrasonography(EUS) for the T and N staging of GLP.EUS examinations of 55 patients with histologically proven GLP were retrospectively studied.In all patients,EUS showed that lesions involved at least one-third of the circumference of the stomach.Based on the findings of the EUS,the 55 patients were divided into two groups.There were 32(58.2%) patients in the first group.EUS of this group showed that the five sonographic layers had disappeared and had been replaced by a hypoechogenic thickening of the gastric wall.There were 23(41.8%) patients in the second group.EUS of this group showed that the first three sonographic layers were blurred and thickened,and the fourth layer was significantly thickened.The full thickness of the gastric wall was significantly thicker in first than in the second group of patients(P<0.01).The incidence of perigastric lesions was significantly higher in the first than in the second group of patients(P<0.01).Results for the 15 patients following preoperative EUS were compared postoperatively with histopathologic findings for T and N staging.The overall diagnostic accuracy of the T stage was 73.3% and of the N stage was 60.0%.In eight patients,we used EUS to assess a therapeutic response.No response was observed in five patients and a partial response in three.EUS images of GLP are characteristic.EUS is helpful in diagnosing GLP and for assessing the T and N stages. 相似文献