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Expert consensus proposes an emergency treatment protocol for portal hypertension bleeding. Herein, the emergency treatment procedures, which include first aid, medical, interventional, and surgical treatments, are described. In addition, the indications, contraindications, operating norms, precautions, and prevention of complications of portal hypertension are described to optimize the first aid process.

The flame method is a kind of new method for preparation of carbon nanotubes. The hydrocarbon gas (acetylene, ethylene, methane) or carbon monoxide is often selected as carbon source gas in this method. Carbon monoxide is a kind of effective carbon source gas in preparation of carbon nanotubes from the high temperature flame compared with hydrocarbon gases. The pentacarbonyl iron is served as catalyst precursor in the experiment. Austenitic stainless steel type316 is selected as sampling substrate in the flame experiment. The carbon nanotubes from the controllable flame have graphite well-crystallized and less structural defects relatively. The nanotube diameter consistency is also relatively good. Carbon monoxide began to decompose at higher temperature than that of hydrocarbon gas and its decomposition rate is suitable for the synthesis of carbon nanotubes in the flame. In addition, the carbon monoxide has the ability to split large iron catalyst particles and prefers to react with iron catalyst. But only a few carbon nanotubes mixed with lots of iron catalyst particles, soot and amorphous carbon particles come into being when low mass flow of carbon monoxide is provided.

Preparation of carbon nanotubes from the controllable flame is a kind of new method. Experimental apparatus is including controllable flame burner, temperature measuring instrument, mass flow meter and catalyst preparation system, etc. The sampling substrate is the growth platform of carbon nanotubes in the flame. The type316 stainless steel is selected as sampling substrate in the experiment. Carbon monoxide provides carbon source and hydrogen/helium premixed gas acts as protection gas. Characterization of the carbon nanotubes on the stainless steel substrate from the controllable flame is by scanning electron microscope (SEM) and transmission electron microscope (TEM). It was found in the experimental that the iron-based catalyst particles are mainly distributed in the ends of the carbon nanotubes. The experimental results reveal that the growth of carbon nanotubes will be very exuberant if the sampling time is controlled within ten minutes.