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1.
"In the early springime, burgeoning flowers look more beautiful in the caress of gentle breeze and against brightness of the pure moon. Ancient beauties, either slim or plump, look gloomier under shining stars... " That is a line from the poem Shi Yue has written. She set the poem to music and named the composition "Charm of Strings". Shi Yue learned music composition as an optional course for one year when she studied in Central Conservatory of Music and got best performance in composition analysis and harmony. "I had highest examination scores in my class. They are quite helpful to my music creation later," Shi said.  相似文献   
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The injury of gunners caused by muzzle shock-wave has always been a great problem when firing inside the protective cover. The distribution regularity and personnel injury from the muzzle blast-wave were investigated by both test and numerical simulation. Through the inside firing test, the changes of overpressure and noise have been measured at different measuring points in the thin-wall cover structure with different open widths and shallow covering thickness. The distribution regularity of muzzle shock-wave with different firing port widths is calculated by ANSYS/LSDYNA software. The overpressure distribution curves of muzzle shock-wave inside the structure can be obtained by comparing the test results with the numerical results. Then, the influence of open width and shallow covering thickness is proposed to give a reference to the protective design under the condition of the inside firing with the same cannon caliber.  相似文献   
4.
语顿浅谈     
本文阐述了语顿的概念,类型及其作用,适时、准确、巧妙地运用语顿可以收到意想不到的表达效果。  相似文献   
5.
Stories about Sanxingdui Culture published in the magazine before have caught readers' great interest. So far there are three major viewpoints about the origin of this mysterious culture. Some experts note that unearthed artifacts in Sanxingdui were legacies of the ancient Shu Kingdom and have nothing to do with foreign cultures. But since no written records have been left about this culture existing more than three thousand years ago, those who support this hypothesis have to resort to a smattering of clues in ancient documents of ensuing periods as well as legendary stories. A rivaling opinion argues that this culture has some relation with the ancient civilizations of Western Asia, Central Asia as well as Aegean Sea. It is believed that Ancient Egyptians already knew how to produce bronzes in the period between 3 800 and 3 500 BC and it is quite possible that the technology was imported to China in some way. In recent years, however, some scholars, based on extensive studies, assert that Sanxingdui is a result of cultural exchange and assimilation. They hold that some tribe lost its way during the great migration of the ancient India-lran tribes and misled itself to Sanxingdui. The tribe settled there and developed a culture that blends elements from both ancient central China and ancient India-lran areas.[第一段]  相似文献   
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A quasi-static wear model for helical gears is proposed based on finite element method and Archard’s formula to investigate the wear characteristics of tooth surface in real operation conditions. The numerical simulation reveals that the wear depth distributes unevenly along the tooth lead and varies along the tooth profile. The surface wear depth claims its minimal value at the pitch circle and reaches its maximal value near the tooth root of the pinion. The effects of misalignment on wear depth are further investigated to provide useful information for gear designers. The numerical simulation reveals that the vertical misalignment is more influential than the parallel misalignment on the gear wear depth. Therefore, to eliminate the negative effects of misalignment, the misalignment should be strictly controlled.  相似文献   
7.
It has been known that there are different kinds of small-scale active phenomena on the Sun. They are classified into spicules, macrospicules, and H-alpha jets, X-ray jets, etc., according to their sizes, velocities, lifetimes, and so on. All these phenomena are related to small-scale magnetic fields. The problems of solar upper atmospheric heating and solar wind acceleration have never been solved. Small-scale magnetic fields and activities are considered to play key roles in heating upper atmosphere and in accelerating solar wind.  相似文献   
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Climate change will lead to a significant alteration in the temporal and spatial pattern variation in the regional hydrological cycle, and the subsequent lack of water, environmental deterioration, flo...  相似文献   
9.
Jun 《新高考》2013,(2):5-6
2013年的冬天特别寒冷,南方是否需要集中供暖的话题再次进入公众的视野.就这个问题,新浪微博上已经初步形成了两大阵营,代表人物各持己见,在网上展开了激烈讨论. Meng Fei,a famous host in Jiangsu TV Station,is the leading representative of the group in favor of starting public heating(集中供暖)in South China.It is true Nanjing has been undergoing(经历,遭受)the coldest winter in the last ten years.People's daily lives are greatly influenced by the cold weather.  相似文献   
10.
We focused on the mathematical modeling and characteristics analysis for the nutation drive based on error parameters. The crown gear tooth profile equation was introduced according to the national standard double circular arc tooth profile and based on the equal tooth strength principle. The nutation drive meshing coordinate system was set up by introducing the cone vertex error, tilt error, nutation angle error and spiral angle error. The tooth profile equations of the double circular arc external and internal spiral bevel gears were further obtained based on the crown gear tooth profile equation concerning above mentioned error parameters. The influences of the nutation gear reducer tooth contact conditions were analyzed with the gear tilt error and axial misalignment error. Finally, the correctness of the theoretical analysis was verified by the contact spot test.  相似文献   
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