共查询到20条相似文献，搜索用时 62 毫秒
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给出了PVT系统的物态方程和热力学微分方程，并通过对描述PVT系统的四个热力学量P、V、T、S的偏导数的讨论，确定了（ЭV/ЭT）p、（ЭV/ЭP）T、（ЭS/ЭT）p为PVT系统的三个基本热力学偏导数。 相似文献
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李山岗 《吕梁高等专科学校学报》2000,16(1):75-76
用Ｐ—Ｖ图作为热力学第一定律的辅助手段定性判断一定质量的理想气体等温、等压和等容三个等值过程的能量转换 ,直观、迅速而且准确 ,是综合运用物理规律和图象解的一个实题的一个实例。 1 一定质量理想气体等值过程Ｐ—Ｖ图简析热力学系统的状态参数Ｐ、Ｖ、Ｔ中如果有两个确定 ,第三个也随之而定 ,且在Ｐ—Ｖ图上能够找到对应的一点 ,表征一个热力学平衡态。每一个状态的变化过程可以用Ｐ—Ｖ图上的一条曲线表示。1 1 在Ｐ—Ｖ图上 ,等温线是彼此不相交的双曲线簇。当温度升高时 ,等温线按图 1中箭头方向移动 ,即等温线Ⅲ比等温线… 相似文献
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介绍热力学状态函数关系式的记忆法,对状态函数的定义、热力学基本方程、特征函数的一阶偏导数关系武、麦克斯韦关系式的记忆进行了探讨。 相似文献
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如何把全频道ＣＡＴＶ系统改为邻频道ＣＡＴＶ系统李必录随着广播电视事业的迅速发展，电视节目资源日趋丰富，这就要求扩充Ｃ＊ＴＶ频道容量。现有全频道ＣＡＴｙ系统从容量上看可传输几十个频道，但实际上在一个全频道ＣＡＴＶ系统内可使用的频道只能达到十几个，显然已... 相似文献
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林培通 《宁德师专学报(自然科学版)》2000,(4)
分析了教学ＶＯＤ系统的特点,介绍一种以现有的ＣＡＴＶ网的宽带下行信道传送ＶＯＤ模拟电视信号,ＰＳＩＮ网为上行信道传送用户信息和控制信号的教学ＶＯＤ系统。 相似文献
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在高中阶段学习“气体的性质”一章时 ,经常会碰到“打气”、“抽气”型题目 ,好多学生感到束手无策 .为了帮助同学们克服这一难关 ,笔者对“打气”、“抽气”型题目作了归纳分析 ,供参考 .一、关于“打气”型问题的解法对于“打气”型题目 ,我们通常用理想气体状态方程的分态式 ＰＶＴ =Ｐ1 Ｖ1 Ｔ1 Ｐ2 Ｖ2Ｔ2 来解决 ,由于在打气过程中 ,往往忽略温度的变化 ,因此可把打气过程看作一个等温过程 ,即Ｔ=Ｔ1 =Ｔ2 ,故往往用ＰＶ =Ｐ1 Ｖ1 Ｐ2 Ｖ2 来解决此类问题 .例 1 给容积为 1Ｌ的贮气钢瓶打气 ,每次能打进 1ａｔｍ的空气 1 2 5ｃｍ… 相似文献
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邱崇丙 《唐山师范学院学报》2014,(1):21-23
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。 相似文献
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《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help? 相似文献
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Rachel Zupek 《海外英语》2007,(11):40-41
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了 相似文献
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YANGShiguo 《重庆大学学报(英文版)》2004,3(1):86-88
The problem on the geometrc inequalities involving an n-dimensional simplex and its inscribed simplex is studied. Aninequality is established, which reveals that the difference between the squared circumradius of the n-dimensional simplex andthe squared distance between its circumcenter and barycenter times the squared circumradius of its inscribed simplex is not lessthan the 2(n-1)th power of n times its squared inradius, and is equal to when the simplex is regular and its inscribed siplex is atangent point one. Deduction from this inequality reaches a generalization of n-dimensional Euler inequality indicating that thecircumradius of the simplex is not less than the n-fold inradius. Another inequality is derived to present the relationship betweenthe circumradius of the n-dimensional simplex and the circumradius and inradius of its pedal simplex. 相似文献
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《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love. 相似文献
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Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject. 相似文献
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GUO Bao-feng Xiao Da-wei 《重庆大学学报(英文版)》2005,4(3):129-133
Using virtual reality for interactive design gives a designer an intuitive vision of a design and allows the designer to achieve a viable, optimal solution in a timely manner. The article discusses the process of making the Virtual Reality System of the Humble Administrator＇s Garden. Translating building data to the Virtual Reality Modeling Language （VRML） is by far unsatisfactory. This creates a challenge for computer designers to do optimization to meet requirements. Five different approaches to optimize models have been presented in this paper. The other methods are to optimize VRML and to reduce the file size. This is done by keeping polygon counts to a minimum and by applying such techniques as object culling and level-ofdetail switching. 相似文献