Melatonin 褪黑素
Melatonin is a hormone primarily released by the pineal gland at night, and has long been associated with control of the sleep–wake cycle.
In vertebrates, melatonin is involved in synchronizing circadian rhythms, including sleep–wake timing and blood pressure regulation, and in control of seasonal rhythmicity including reproduction, fattening, ...
Civil Aviation 民航
Civil aviation is one of two major categories of flying, representing all non-military and non-state aviation, both private and commercial. Most of the countries in the world are members of the International Civil Aviation Organization (ICAO) and work together to establish common standards and recommended practices for civil aviation through tha...
Rocket Equation 火箭方程
Rocket equation is a mathematical equation that describes the motion of vehicles that follow the basic principle of a rocket: a device that can apply acceleration to itself using thrust by expelling part of its mass with high velocity can thereby move due to the conservation of momentum.
Ideal Rocket Equation
\[\Delta v=v_{\mathrm{e}} \ln \fra...
Ai 人工智能
Artificial super intelligence is humanity’s last invention, no reason to be scared.
Let’s take a journey into the future and explore how Ai develops
and changes humanity paving the way for robots that are too fast
for humans to see in 10 years time, for the creation of Ai-free zones in 60 years.
For energy being rationed for humans to power the ...
Earthquake 地震
Quaking or shaking of the earth is a common phenomenon undoubtedly known to humans from the earliest times. Before the development of strong-motion accelerometers that can measure peak ground speed and acceleration directly, the intensity of the earth-shaking was estimated based on the observed effects, as categorized on various seismic intensit...
DSN 深空网络
Deep Space Network (DSN) currently consists of three deep-space communications facilities placed approximately 120 degrees apart around the Earth. They are:
the Goldstone Deep Space Communications Complex (35°25′36″N 116°53′24″W) outside Barstow, California. For details of Goldstone’s contribution to the early days of space probe tracking.
...
CRISPR 基因编辑
Clustered Regularly Interspaced Short Palindromic Repeats
Repetitive DNA sequences, called CRISPR, were observed in bacteria with spacer DNA sequences in between the repeats that exactly match viral sequences. It was subsequently discovered that bacteria transcribe these DNA elements to RNA upon viral infection. The RNA guides a nuclease (a pro...
Private Jet 私人飞机
A private jet, business jet, or bizjet is a jet aircraft designed for transporting small groups of people. Business jets may be adapted for other roles, such as the evacuation of casualties or express parcel deliveries, and some are used by public bodies, government officials or the armed forces.
Most production business jets use two jet engine...
71 post articles, 9 pages.