PQDD(ProQuest Digital Dissertations)是由美国Bell& Howell信息学术公司Bll Howell Information and learning,原为UM公司)提供的“国际学位论文文摘”数据库的 web版。它是目前世界上独一无二的最具权威性的博士、硕士学位论文检索数据库,主要 收录来自美国、加拿大和欧洲1000多所大学的博、硕士论文的题录、文摘共160余万 篇,其中100多万篇有印刷型或缩微型原文收藏。该数据库每周更新一次数据,每年大约 新增47000篇博土论文和12000篇硕士论文
Heart as Strong as Iron\ Techniques Checklist: Use of a centrifuge Equipment: Disposable UV-Vis cuvettes 1-mL capacity) .Pipetmen: 20P, 100 P, 1000 P .Pipet tips Eppendorf tubes (safe-lock) .Hot plate
1 The switch in Fig.5-27 is opened at=0, Find i (0*) and v (0*) 1kΩ D100v 1k2 Fig. 5-27 For prob.1. The switch is closed at= 0 in Fig.5-28. Find i(*) and ic(0*) if the capacitor is initially
Carbon atoms have the ability to link together and form molecules made up of many carbon atoms. The branch of chemistry that is the study of carbon-containing compounds is known as organic chemistry(有机化学) 13 million known organic compounds and 100,000 new ones are added annually Only 200,000-300,000 known inorganic compounds
