南开99普通生物学 一.名词解释:(40%10×4%) 1.食物链 2.D0 3.平流层 4.TSP 5.苯并(a)芘 6.LEq 7.辐射逆温 8.土地处理系统 9.生物多样性 10.赤潮

一、复杂性研究 1 早期阶段（20世纪40年代） A系统论：生物学家贝塔朗菲于20世纪30-40年代提出系统论思想。贝塔朗菲认为存在着适用于综合系统或子系统的模式、原则和规律，而不论种 类、组成部分的性质和它们之间的关系或力的情况如何，任务是确立适用于系统的一般原则

I If f(t)=100 for 04.(a) Calculate v at t=T/4.(b) Find the average power delivered by this waveform to a 5Q2 resistor 3 Let v(t)=3-3 cos(100 t-40)+4 sin(200 T t-10)+2.5 cos 300 tt V Find: (a)the average value Var;(b)the rms value V;(c)the period T; (d)v(18ms)

1.经纬仪测量水平角时,正倒镜瞄准同一方向所读的水平方向值理论上应相差() A180°B0°C90°D270° 2.1:5000地形图的比例尺精度是() A5 m B0. mm C5 cm D 50 cm 3.以下不属于基本测量工作范畴的一项是() A高差测量B距离测量C导线测量D角度测量 、一、单项选择题 4.已知某直线的坐标方位角为220°,则其象限角为() 在下列每小题的日 A220° B40° C南西50° D南西40° 案,并将其字母标号填

将 40 只 14 日龄蛋用雏鸡随机分成 2 组 ,每组 20 只 ,A 组为对照组 ,颈部皮下注射新城疫疫苗 0. 2ml/ 只 ,B 组为试 验组 ,在颈部皮下注射新城疫疫苗的同时 ,每只雏鸡投服缓释复方免疫增强剂 1 粒(0. 25 mg 左右) ,在试验后 10、20、30 和 40 d 时检测的新城疫 HI 抗体效价

A VNi atomic model for 3D periodic structure is posed based on T polyhedrons which are introduced. The fourier transform patterns of the atomic model may explain the 12-fold symmetry in electron diffraction patterns of V60Ni40 alloy. This is the first satisfactory explanation since the V60Ni40 alloy has been reported

Logistics We(provisionally) meet on Tuesdays and Thursdays 10: 40a-12: 10p, in Bendheim 317. I will create a mailing list for the course. Therefore please send me email at your earliest convenience so I can add you to the list. You do not want to miss important announcements, do you? the course has a web page at http://www.princeton.edw

采用凸轮式形变试验机,在高温高速下对20Cr、40Cr、T8A,T12A等四种钢进行压缩时塑性变形阻力的试验研究。试验范围:变形温度:850～1150℃;变形速度:5～80秒1;变形程度:emax=1n2。本文着重分析了变形温度、变形速度、变形程度对20Cr、40Cr、T8A、T12A等四种钢塑性变形阻力的影响关系及20Cr与40Cr,T8A与T12A试验结果的比较。并提供了供工程技术人员和轧钢生产中可实际使用的塑性变形阻力的计算公式和计算图表。同时还运用T8A的试验结果与各国学者的试验结果进行了比较

Marciano Siniscalchi Game Theory (Economics 514) Fall 1999 Logistics We(provisionally) meet on Tuesdays and Thursdays 10: 40a-12: 10p, in Bendheim 317. I will create a mailing list for the course. Therefore please send me email at your earliest convenience so I can add you to the list. You do not want to miss important announcements, do you?

High temperature corrosion tests in 75%Na2SO4-25%. NaCl molten salt have been conducted on waspalloy specimens plasma sprayed with Co-Cr-B-Si, Ni-Cr-B-Si-hCr3C2, X-40, X-40 + TiC and Ni/Al + Al2O3 coatings, test coupons were exposed isothermally at 750℃up to 200 h. After the corrosion tests, each sample was examined by OM, SEM and EMPA. It was found that X-40, X-40 + TiC and Ni/Al + Al2O3 were violently corroded by the molten salt due to cracking and spalling of the coatings, whereas Co-Cr-B-Si and Ni-Cr-B-Si + Cr3C2 exhibited superior corrosion resistance, which were thought to be related to the formation of chromium and silicon oxide film. A possible corrosion mechanism had been proposed and it is suggested that the excellent corrosion resistance and high hot-hardness of the two B-Si containing coatings may be of significance for applications in petroleum refining industry as