Abstract: Disclosed is an electronic cigarette, which includes a case body, a bottom cover mounted on the case body and a burning room for accommodating tobacco. A heating net is provided in the burning room; the case body is provided with a first accommodating chamber and a second accommodating chamber in which a power supply and a control circuit are provided, the burning room being provided in the first accommodating chamber; the heating net, the power supply and the control circuit are connected in series by means of lead wires; and the electronic cigarette further comprises a mouthpiece connected with the burning room and a switch assembly for controlling the control circuit. The present invention has an advantage that the temperature of the heating net can be increased quickly so that the tobacco in the burning room can burn in a short time.

Abstract: This invention discloses an e-cigarette, integrated with functions of grinding, cutting and heating, comprising a case, wherein: the case is divided into a smoke control room and a grinding-cutting-hewing room. Upper part of the grinding-cutting-heating room comprises a tobacco grinding-cutting module and a heater and lower part of it comprises a rotatable ash funnel. A hole is set on the bottom of the ash funnel and combined with an air vent located on the bottom of the case to form a smoke ventilating passage. The upper part of the smoke control room comprises a cigarette holder, the cigarette holder connects a flexible conduit via a connector. The flexible conduit is connected to the grinding-cutting-heating room located on the other side. The lower part of the smoke control room comprises a power source, and the power source is connected to a PCBA on the same side.

Abstract: A stereospecific synthesis process for tretinoin compounds comprises the following steps: using substituted triphenyl phosphine salt and ?-formyl crotonic acid as raw material to carry out WITTIG reaction under the action of alkali; then adjusting the pH of the reaction liquid to 5-10; adding palladium compound or rhodium compound to carry out isomerization directly and obtain tretinoin compounds with desired configuration. The product yield of the process is high and the intermediate product in the reaction dose not need to be separated. The process is easy to operate and can save the production cost and as well is suitable for industrial production.

Abstract: A stereospecific synthesis process for tretinoin compounds comprises the following steps: using substituted triphenyl phosphine salt and ?-formyl crotonic acid as raw material to carry out WITTIG reaction under the action of alkali; then adjusting the pH of the reaction liquid to 5-10; adding palladium compound or rhodium compound to carry out isomerization directly and obtain tretinoin compounds with desired configuration. The product yield of the process is high and the intermediate product in the reaction dose not need to be separated. The process is easy to operate and can save the production cost and as well is suitable for industrial production.