1.放射性同位素的蜕变速率符合一级反应的规律(蜕变速率与放 射性同位素的数量成正比)。210Po经a蜕变生成稳定的206Pb: 210Po206pb+4He 实验测得14d后放射性降低了6.85%,试求2Po的蜕变速率系数和半 衰期,并计算它蜕变掉90%时所需要的时间

《大学物理》课程PPT教学课件（二）第14章 波的产生和传播——有关机械波的基本概念、波动过程的描述

2.1宇宙演化与物质形成(12) 2.1.1宇宙、星系和恒星(12) 2.1.2宇宙起源、恒星演化与元素形成(12) 2.2太阳系形成与行星地球的特殊性(13) 2.2.1太阳系的形成和演化(13) 2.2.2行星地球的特殊性(14) 2.2.3地球外生命的探索(15) 2.3地球演变与生命起源(17)

14-3旋转矢量

Types of Decisions Programmed Nonprogrammed Repetitive and routine Novel and unstructured decisions and where a decisions required for definitive procedure is unique and complex developed to handle them management problems. McGraw-HillInwin

Constructive Solid Geometry(CSG) 14.2 Primitives of CSG 14.3 Boolean operators 14.3.1 Regularized Boolean operators 14.4 Set membership classification 14.5 Properties of CSG

Molecular Biology of the Gene, 5/E---Watson et al. (2004) Part: Chemistry and Genetics Part ll: Maintenance of the Genome Part Ill: Expression of the Genome Part IV: Regulation Part V: Methods

Deployment and Geometry Maintenance Deployable Membranes Used for solar arrays, sunshields, decoys Being researched for apertures starting at RF and eventually going to optical Inflatables First US satellite was inflated (ECHO D) Enables a very large deployment ratio -=deployed over stowed dimension

24.00: Problems of Philosophy Prof. Sally Haslanger November 7, 2001 Freewill IlI: Libertarianism I. Recap: Compatibilism v. Incompatibilism Hard determinism is the view that determinis is true and that because of this freedom is an illusion. The libertarian agrees with the hard determinist that freewill is incompatible with determinism, but disagrees about which claim should be rejected. The libertarian holds that we have free will, but this is only because determinism is false-free acts occur and are undetermined. The hard determinist and the libertarian are both incompatibilists. Soft determinism, also known as compatibilism, maintains that determinism is true, but also that determinism is

一、世界通信公司造假收入38亿美元 6月25日,美国第二大长途电话公司世界通信公司(World Com)发表声 明,承认自2001年初到2002年第一季度通过将大量的费用支出计入资本项 目的手法,共虚增收入38亿美元,虚增利润16亿多美元。其中,2001年度虚 增收入30.6亿美元,2002年第一季度为7.97亿美元。该公司原报告的2001年 度14亿美元和今年第一季度1.3亿美元的利润,实际是净亏损。为该公司提供 财务报表审计的是安达信公司。 据美国媒体报道,这是美国历史上迄今为止金额最大的会计欺诈事件。由 于世界通信公司目前负有300亿美元的巨额债务,有关分析人士认为其申请破 产在所难免。如果该公司破产,其申请破产的资产总额(1000亿美元)将是安 然公司的2倍,从而将成为美国历史上最大的破产案。 世界通信公司在曝出假账丑闻后,该公司的股票在华尔街股市上一路狂 泻,4年前每股曾高达64.50美元的股价跌至6月26日收盘时的9美分