189 results about "Plasma channel" patented technology

An electrosurgical device to generate a plasma stream and method to perform endoscopic or laparoscopic surgery within a patient's body comprising an electrosurgical generator coupled to a electrical power source to supply power to the electrosurgical device and a plasma generator including an electrode operatively coupled to the electrosurgical generator to receive electrical energy therefrom and concentrically disposed within an inner noble gas conduit to form a plasma channel coupled to a noble gas source to feed noble gas to the inner noble gas conduit and an outer electronegative gas conduit disposed in surrounding coaxial relation relative to the inner noble gas conduit to cooperatively form an electronegative gas channel therebetween coupled to a gas source to feed electronegative gas to the electronegative gas channel or an outer aspiration conduit disposed in surrounding coaxial relation relative to the inner noble gas conduit to cooperatively form an aspiration channel therebetween coupled to a negative pressure source such that the electrode heats the noble gas to at least partially ionize the noble gas to generate the plasma stream to be directed to the surgical site to perform the surgical procedure while the electronegative gas sustains the plasma stream at the surgical site and dilutes the noble gas adjacent the surgical site or the negative pressure source removes fluid and solid debris from the surgical site respectively.

A plasma generating apparatus having superior plasma generation efficiency that uses a single reaction chamber. The plasma generating apparatus includes a RF generator for providing a RF power, an antenna for generating an electromagnetic field upon receiving the RF power, a reaction chamber for exciting / ionizing a reaction gas via the electromagnetic field, and generating a plasma, and a plasma channel for absorbing the RF power, and allowing a current signal to be induced to the plasma.

The invention discloses a method for heating oil shale underground in situ. According to the method, shale oil and fuel gas can be obtained from an underground oil shale seam in situ, and the fuel gas can also be obtained from an underground coal seam in situ. Wells are drilled downwardly from the ground surface, and the drilling depth of each well reaches the inside of an operation region of an underground oil shale ore bed. At least two wells are drilled, and electrodes are placed in the wells. Firstly, high-voltage electricity which is sufficient to cause partial discharge of the oil shale ore bed is conducted into the electrodes, and then a plasma channel is formed in the oil shale ore bed and can be subjected to breakdown by the high-voltage electricity; after the resistance of each of two electrode regions is lowered, the two electrodes are used for conducting currents into the plasma channel in the oil shale ore bed; the oil shale ore bed is heated under the resistance heating function of the plasma channel; and released heat is used for realizing thermal cracking and gasification of fixed organic carbon in the oil shale ore bed. Through the method for heating the oil shale underground in situ, the heating speed of an underground ore bed can be increased, hydraulic fracturing does not need to be carried out on a rock stratum, and the use of poisonous conductive materials is avoided at the same time.