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1.
中国9月3日中国抗日战争胜利纪念日(September 3rd, Victory of Chinese Peo- ple's War of Resistance against Japanese Ag- gression) 9月9日毛泽东逝世纪念日(Sept.9th,Commemorating Day of the Death of Mao Zedong) 9月10日中国教师节  相似文献   

2.
9月3日中国抗日战争胜利纪念日 (September 3rd, Victory of Chinese People's War of Resistance against Japanese Aggression)[第一段]  相似文献   

3.
继亚里士多德"不需要考虑生存问题的心无羁绊(ab-sence of the necessity of being occupied)的状态"[1]6之定义后,西方学者对"休闲"作出诸多界定。有学者总结说,休闲存在于时间(ti me)、活动(activity)、存在方式(state of exist-ence)、心态(state of mind)四种基本语境之中[1]3-4。中国学者则有从"身"、"心"两维度理解休闲者,  相似文献   

4.
1.China(中国)—the Divine Land(神州)2.Japan(日本)—the country of cherries(樱花国)3.Cuba(古巴)—the country of sugarcane(甘蔗国)4.Panama(巴拿马)—the butterfly country(蝴蝶国)5.Malaysia(马来西亚)—the rubber country(橡胶国)6.Egypt(埃及)—the country of th  相似文献   

5.
1.China(中国)—the Divine Land(神州)2.Japan(日本)—the country of cherries(樱花国)3.Cuba(古巴)—the country of sugarcane(甘蔗国)4.Panam a(巴拿马)—the butterfly country(蝴蝶国)5.M alaysia(马来西亚)—the rubber country(橡胶国)6.Egyp(t埃及)—the country of  相似文献   

6.
The complex heat of BF_3 with methanol was measured by utilizing the principle of the Bunsen ice calorimeter. The complex heat of BF_3 –methanol was found to be 49.2 and 58.1 kJ/mol when the molar ratio of BF_3 to methanol was 1:2 and 1:1,respectively. In addition,the complex heat of BF_3 –anisole was also measured to test the apparatus error. The BF_3 –anisole result showed a calorimeter value of 53.1 kJ/mol with a system error of 2.3% as compared with the value reported in the literature. The mechanism of the reaction of BF_3 and methanol was interpreted based on our obtained results. This apparatus is useful and suitable for measuring the heat of other liquid–gas and liquid–liquid reactions.  相似文献   

7.
Long lasting strontium aluminate phosphors were synthesized by means of coated precipitation in the experiment. SrA12O4 monoclinic phase with long afterglow was synthesized at 1 100 ℃ with the aid of H3BO3,and the synthetic temperature decreased about 100 ℃-150 ℃ than in solid state reaction. The process of heat treatment was studied by TG-DTA. The phase compositions of powders were analyzed by XRD. The micrographs of the samples were investigated by SEM and the luminescent properties were researched by optical spectrum. The effects of H3 BO3 on the phase composition and microstructure of the calcined powders were investigated. The results indicated that H3BO3 accelerated the formation of SrAl2O4 by consuming the intermediate phase. The addition of Dy2O3 stimulated the afterglow property due to the increase in the depth of the trap center in the materials.  相似文献   

8.
Nanostructures enhance phonon scattering and improve the figure of merit of thermoelectric materials. Nanosized CoSb3 skutterudite was synthesized by solvothermal methods using CoCl2 and SbCl3 as the precursors. A "two-step" model was suggested for the formation of CoSb3 based on the X-ray diffraction analysis. The first step is the formation of cobalt diantimonide in the earlier stage during the synthesis process. Diantimonide was then combined with antimony atoms to form the skutterudite structured triantimonide, CoSb3, in the later stage of the synthesis process as the second step. The synthesized CoSb3 powders consist of irregular particles with sizes of about 20 nm and sheets of about 80nm.  相似文献   

9.
Synthesis of Enriched 10B Boric Acid of Nuclear Grade   总被引:2,自引:2,他引:0  
An economic and effective method of preparing enriched 10 B boric acid was established by chemical reaction of enriched 10BF3 and CaCO3. A process of boron trifluoride reacting with water was investigated under certain conditions. Calcium carbonate was selected to counteract hydrofluoric acid followed on. Some key operation factors were investigated, such as temperature, reaction time and the ratio of CaCO3 to 10BF3. The results showed that the yield of enriched 10 B boric acid could reach 97. 2% and the purity was up to 94. 1% under the following conditions: the temperature was 50—60,℃, the reaction time was 28 h and the ratio of CaCO3 to 10BF3 was 4. In addition, after recrystallization and titration analysis, the purity of the product could reach over 99. 2% from 94.1%.  相似文献   

10.
A series of Lil-xNaxV3O8 materials was prepared by solution reaction followed by calcination method and their electrochemical performances in 2 M LieSOa-water-ethanol solution as negative electrodes for aqueous electrolyte lithium ion battery were studied and compared each other. X-ray diffraction analysis revealed that partially substituting sodium for lithium in LiV3Os could increase the interlayer distances of (100) plane. Cyclic voltammetric experiments have demonstrated that the Li^+ insertion and extraction kinetics of Li0.7Na0.3V3O8 is superior to that of LiV3O8. Charge/discharge results showed that the discharge specific capacity of Li0.7Na0.3V3O8 electrode is higher than that of LiV3O8 electrode.  相似文献   

11.
After a necessary condition is given, 3-rainbow coloring of split graphs with time complexity O(m) is obtained by constructive method. The number of corresponding colors is at most 2 or 3 more than the minimum number of colors needed in a 3-rainbow coloring.  相似文献   

12.
The aim of this research is to characterize the development of fatigue damage by means of stress-strain hysteresis. Experiments were conducted on 14 specimens made of cold-finished unannealed AISI 1018 steel. Results demonstrate that the mechanical hysteresis loop areas, when plotted as a function of the number of loading cycles, show significant variations and demonstrate the three principal stages concerning the progress of the fatigue failure--initial accommodation, accretion of damage and terminal failure. These three stages of fatigue are marked by the transitions at cycles N2 and N3. Experimental results show that although fatigue life Nf ranges from 2644 cycles to 108 992 cycles, the ratios of N2/Nf and N3/Nf tend to be stable: N2/Nf=I 0.7%, N3/Nf=91.3%.  相似文献   

13.
The effects of SO2, SO3 on de novo synthesis of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were studied using model fly ashes incorporating copper oxide and activated carbon. It was found that the inhibitive effect of SO2 on PCDD/Fs formation is similar to that of SO3. To investigate the inhibition mechanism, CuSO4 formations from both CuO and CuCl2 were examined. The ability of SO3 to convert CuCl2 and CuO on a silica support into sulfate is much stronger than that of SO2. However, replacing silica by activated carbon leads to a much high conversion of CuCl2 to CuSO4 in the presence of SO2. The promotion by activated carbon is explained by the reduction of CuCl2 to Cu2Cl2 and the eventual conversion of Cu2Cl2 into CuSO4 is the main inhibition mechanism of SO2 on de novo synthesis of PCDD/Fs.  相似文献   

14.
硼对金属间化合物Ni_3Fe氢气诱发环境氢脆的影响(英文)   总被引:1,自引:0,他引:1  
In this paper the tensile properties of both ordered and disordered Ni-24Fe and Ni-24Fe-0.03%B(wt%)alloys in gaseous hydrogen was investigated.The result shows that the ductility of the disordered Ni_3Fe is significantly larger than that of ordered material in gaseous hydrogen.However,the ductility of ordered Ni3Fe doped with 0.03%B is nearly the same as that of disordered one indicating the obvious suppressing effect of boron on the H_2-induced embrittlement.Based on the segregation behavior of boron in Ni_3Al,it is proposed that the suppressing effect of boron in Ni_3Fe on the H_2-induced embrittlement is attributed to the segregation of boron on grain boundaries,thereby reducing the hydrogen diffusivity along the grain boundaries.  相似文献   

15.
Y^3+-doped (Bi 1/2 Na 1/2) TiO 3-CaTiO 3-BaTiO 3 (BNCBT) positive temperature coefficient of resistivity (PTCR) ceramics sintered in air atmosphere were investigated in this study. (Bi 1/2 Na 1/2) TiO 3 (BNT) component can remarkably increase the onset temperature T c of PTCR ceramics with the expense of the resistivity R 25 increase. CaTiO 3 (9–27 mol%) component can decrease the resistivity, and adjust the effects of BNT phase on the T c point. For the sample containing 3 mol% CaTiO 3 , T c raises from 122 ℃ to 153 ℃ when only 0.6 mol% BNT added, while for the ones with higher CaTiO 3 content (9–27 mol%), T c is only increased by a rate of 8–9℃/1.0 mol% BNT. The effects of BNT and CaTiO 3 components on R25/Rmin (negative temperature coefficient effect) are also discussed.  相似文献   

16.
Nitrogen doping of activated carbon loading Fe2O3 was performed by annealing in ammonia, and the activity of the modified carbon for NO reduction was studied in the presence of oxygen. Results show that Fe2O3 enhances the amount of surface oxygen complexes and facilitates nitrogen incorporation in the carbon, especially in the form of pyridinic nitrogen. The modified carbon shows excellent activity for NO reduction in the low temperature regime (<500 °C) because of the cooperative effect of Fe2O3 and the surface nitrogen species.  相似文献   

17.
下面是外国人笔下的中国谚语,你能将它们还原吗?试试看。1.Add legs to the snake after you have finished drawing it. 2.A book holds a house of gold. 3.Crows everywhere are eqnally black. 4.Dream different dreams while on the same bed. 5.Even a hare will bite when it is cornered. 6.Have a mouth as sharp as a dagger,but a heart as soft astofu. 7.An inch of time is an inch of gold,but you can’t buy that inch of time with an inch of gold. 8.Looking for the ass on its very back.  相似文献   

18.
In this paper the tensile properties of both ordered and disordered Ni-24Fe and Ni-24Fe-0.03%B (wt%) alloys in gaseous hydrogen was investigated. The result shows that the ductility of the disordered Ni3Fe is significantly larger than that of ordered material in gaseous hydrogen. However, the ductility of ordered Ni3Fe doped with 0.03%B is nearly the same as that of disordered one indicating the obvious suppressing effect of boron on the H2-induced embrittlement. Based on the segregation behavior of boron in Ni3A1, it is proposed that the suppressing effect of boron in Ni3Fe on the H2-induced embrittlement is attributed to the segregation of boron on grain boundaries, thereby reducing the hydrogen diffusivity along the grain boundaries.  相似文献   

19.
N2 and N3 are known as the transition points of the three principal stages of fatigue: initial accommodation, accretion of damage and terminal fatigue. Many experiments show that the ratios of N2/Nf and N3/Nf tend to be stable even though the specific N2 and N3 values may fluctuate widely. The primary goal of this research is to study the piezomagnetic field surrounding AISI 1018 steel specimen under repeated loads and to find the ratio values of N2/Nf and N3/Nf by analyzing 11 sets of low-cycle fatigue data. An MTS-810 testing system with a peak capacity of 222 kN was used to obtain the data which consisted of stress, strain, and piezomagnetic field. A computer program was constructed to track the evolution of the piezomagnetic field and regression analysis was carried out to determine N2 and N3 values. It was observed that there exists a consistent relationship between N2 and Nf. The apparent invariance of the ratio N2/Nf implies that N2 may be identified as an index of performance in the early loading response of a specimen that forecasts its fatigue life, Nf. It has been demonstrated that measurements of the magnetic and mechanical hysteresis can yield significant insights into the various stages of the development of a fatigue critical microstructure which culminates in complete rupture of the material.  相似文献   

20.
Based on the Industrial Source Complex Short-Term Version 3 (ISCST3) model, a simplified modeling approach was developed to predict concentrations of congeners of polychlorinated-p-dioxins and dibenzofurans (PCDD/Fs) of agricultural soil, within a radius of 3 kin from a municipal solid waste incinerator (MSWI) plant after its 4-year operation in Hangzhou, China. Comparisons were made between the measured and estimated congener-specific concentrations and the international-toxic equivalent (I-TEQ) values of soil samples with respect to distance from the stack. The results indicate that the predictions of soil PCDD/F concentrations and K-TEQ values were generally lower than their observations, and that the higher the degree of underestimation seems, the greater the further downwind one gets. Nevertheless, most of the predictions were in good agreement with the trend of measured ones and were within a factor of ten for samples located within 1 kin of the plant. Besides, analysis of contributions of various deposition pathways confirms that in addition to wet particle deposition, the dry gaseous deposition is essential for realistic prediction of PCDD/F depositions to soil, especially for tetra- and penta-chlorinated dioxins.  相似文献   

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