explain which notable events occurred in january of 1923
Here are some notable events that occurred in January of 1923:

1. January 3: The French army occupies the Ruhr region of Germany, a coal-rich area that had been subject to reparations following World War I.

2. January 5: Ku Klux Klan members in the US stage a massive rally in Washington D.C., with an estimated 40,000 people in attendance.

3. January 11: French and Belgian troops clash with German workers in the Ruhr region, leading to several deaths and injuries.

4. January 16: The Walt Disney Company is founded by Walt Disney and his brother Roy, with the creation of the first Disney cartoon character, Oswald the Lucky Rabbit.

5. January 23: The Netherlands and Belgium sign the Customs Convention, which creates a customs union between the two countries and lays the groundwork for the creation of the Benelux economic union.

6. January 30: The Soviet Union announces the establishment of diplomatic relations with Germany, following several years of tension between the two countries.

These are just a few of the notable events that occurred in January of 1923. Other events from that month include political and social unrest in several countries, technological and scientific breakthroughs, and cultural and artistic developments.
Elaborate about the technological and scientific breakthroughs occurred.
There were noteworthy events in telecommunications, aeronautical engineering, and chemistry. 

 - January 14th: The first reliable wireless transmission of voices was broadcast across the Atlantic Ocean. The call was sent from H. B. Thayer in New York, president of American Telephone and Telegraph (AT&T) who developed the technology, to Guglielmo Marconi who was listening in London. 
  - January 17th: The first practical helicopter, designed by Spanish engineer Juan de la Cierva, takes flight outside of Madrid. It was documented to have flown a distance of 600 feet while maintaining an altitude of 13 feet. 
  - January 19th: Dirk Coster and George de Hevesy discover element 72, hafnium in Copenhagen, Denmark. The discovery came 54 years after Dmitri Mendeleev first predicted its existence in 1869.