AFTER full discussion of the new determinations 1–3 of the half-life of carbon-14, the Fifth Radiocarbon Dating Conference, meeting at Cambridge (see p. 943 of this issue of Nature), adopted the ...

像去年一样，科学家们将“世界末日时钟”上的时间设置在距离午夜只有90秒的位置。 俄罗斯入侵乌克兰。以色列和哈马斯之间的战争。中国快速 ...

我设计两个窗口，一个主窗口（mainwindow）一个子窗口（sub），其中主窗口用来实现基本的题目要求，有如下表所示几个模块 ...

If the artifact is organic—like wood or bone—researchers can turn to a method called radiocarbon dating. It's a process that dates an object by analyzing the different forms of carbon it contains.

具有时间延迟的单调延迟补偿还可以在电源和温度变化范围内稳定工作。时间延迟IC产品通常用于从仪器仪表到航空航天的高数据速率应用中的时钟同步。 ADI时间延迟IC产品具有高达2.5 GHz的延迟控制调制带宽。我们的产品系列还提供具有0 ps至70 ps连续可调延迟 ...

ADI公司提供面向设备设计的分立式速率、多速率和连续调谐时钟和数据恢复IC，包括城域网络、远程、DWDM和FSO应用。ADI CDR可轻松集成到与协议无关的应用中，无需借助参考时钟，也可自动锁定12.3 Mbps至2.7 Gbps范围内的任意速率输入数据流，同时还能通过I2C接口 ...

世界时钟工具（World Clock Tool），是一款用于全球城市时区查询设计的小型工具。它的主要功能是帮助用户了解并管理他们的时区，无论是在旅行、工作还是日常生活中，都能提供一定的便利。 适用于对时区有需求的人群，包括但不限于： 旅行者：在计划旅行时 ...

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Editor’s note: This is part of a series called “The Day Tomorrow Began,” which explores the history of breakthroughs at UChicago. Learn more here. Radiocarbon dating, or carbon-14 dating, is a ...

Radiocarbon dating is one of the key discoveries of the twentieth century. Archaeologists have recently begun to employ high precision radiocarbon dating to explore the chronology of the Iron Age in ...

We independently review everything we recommend. When you buy through our links, we may earn a commission. Learn more› By Joanne Chen and Annie Chou Our upgrade pick, the Philips SmartSleep ...