After Marrying a Vegetative Princess, I Went Crazy With Joy! - Chapter 13: The eighteenth technician Su Li, apply for the post.

A scientific genius named Thomas Harrier was transmigrated to an imperial prince body after a car accident that took his life. He found out that he is in a world similar to our own with a timeline akin to early twentieth century. The body that he is occupying was the imperial prince of a failing empire who suddenly rose to power after a successful assassination attempt of his father. Unaware that the attack is just the beginning of what is to come. He faces many challenges throughout. Will Thomas Harrier be able to live his second life in peace while running an empire and getting it back to its former glory? Or will he succumb into a conspiracy lurking within the country's borders?

Expect some:

Cold war era techs.

Super battleship with advanced electronics, propulsion, and fire control systems?
Helicopters?
Missiles?
Modern medicines and equipment?
AC-130?
A nuke?
Challenger or Abrams or Leopard?
F-4 Phantom or MIG-21?
Colored TV's.

Everything!!!

PS. Cover not mine, I just found it on google.

(The main story has ended!! A 1v1, sweet and clean romance novel) Shen Chuwei suddenly travels back to ancient times to become a neglected concubine of the Crown Prince. She thought it was the beginning of a leisurely life of eating and drinking, but unexpectedly, she ends up being deeply pampered by the aloof Crown Prince.Lady Xu: “Shen Fengyi, you'd better know your place. Tonight is my turn to serve His Highness.”Shen Chuwei says: “The Crown Prince is yours, I promise I'm just here to freeload.”That night, Shen Chuwei was kept in the Crown Prince's room~Lady Chang: “The Crown Princess is mine. You can't even dream of sharing her.”Shen Chuwei replies: “I'm not interested.”Later on, not only does Shen Chuwei become the Crown Princess, but she also gives birth to a pair of twins. The Emperor and Empress are in a scramble to pamper them, guaranteeing a smooth ride to victory.All the women in the East Palace vie to become the Crown Princess through their cunning and devious methods, yet all of these are clearly seen by Xiao Jinyan, who has the ability to read minds, causing him to avoid them.That is, until he sees a small 'salted fish', sweet-talking and soft-bodied, just to his liking, “You will serve me tonight.”As a freeloading 'salted fish', she trembles in fear: “Your Highness, I'm still too young.”

When she agrees to help her friend out in a blind date, she never imagined it would lead her to the one man she'd hoped never to encounter again—her child's father.Her first instinct? Run. But life has other plans, and she finds herself inescapably drawn back into his orbit as his company's legal advisor.Just as she's poised to resign, escaping the tangled web of personal and professional ties, she's cornered in his office by the man who is as relentless in business as he is in pursuit of her heart.In a game of cat and mouse, she is faced with a choice: succumb to the undeniable chemistry that still sizzles between them or risk it all to maintain the distance she's fought so hard to keep.