Abstract: A heat exchange tube is used to solve the problem of insufficient heat exchange efficiency of the conventional heat exchange tube. The heat exchange tube includes a tube, a first porous layer, and a second porous layer. The tube includes an inner wall. The first porous layer includes a plurality of holes. The first porous layer is disposed on the inner wall of the tube. The second porous layer includes a plurality of holes. The second porous layer is disposed on an inner surface of the first porous layer. An average diameter of the plurality of holes of the second porous layer is greater than an average diameter of the plurality of holes of the first porous layer. A method for manufacturing a heat exchange tube is also disclosed.

Abstract: The present invention discloses a bandpass amplifier having gain and bandpass performance. The bandpass amplifier includes an input match unit for matching the gain of the amplifier and having a first filter response; a first bias unit electrically connected to the input match unit for driving the first terminal of the amplifier and having a first high pass filter response; a gain stage electrically connected to the first bias unit for providing the flat gain of the amplifier; a second bias unit electrically connected to the gain stage for driving the second terminal of the amplifier and having a second high pass filter response; and an output match unit electrically connected to the second bias unit for matching the gain of the amplifier and having a second filter response.

Abstract: The present invention discloses a bandpass amplifier having gain and bandpass performance. The bandpass amplifier includes an input match unit for matching the gain of the amplifier and having a first filter response; a first bias unit electrically connected to the input match unit for driving the first terminal of the amplifier and having a first high pass filter response; a gain stage electrically connected to the first bias unit for providing the flat gain of the amplifier; a second bias unit electrically connected to the gain stage for driving the second terminal of the amplifier and having a second high pass filter response; and an output match unit electrically connected to the second bias unit for matching the gain of the amplifier and having a second filter response.

Abstract: A method of fabricating quantum dot structures and devices including the steps of: (i) forming a quantum well membrane on a substrate; (ii) on the quantum well membrane forming a masking layer including a plurality of dot-shaped mask regions which protect the underlying quantum well membrane; (iii) using thermal etching to evaporate portions of the quantum well membrane that are not protected by the dotted mask regions of the masking layer so as to form a plurality of quantum dots; and (iv) after thermal etching, covering the plurality of quantum dots with a layer of material having an energy gap that is greater than the energy gap of the quantum well membrane. The quantum dot produced by this invention is found to generate ten times more illumination than the prior art when measured by photoluminescence.