摘要:
A scanning tunnel spectroscope comprises a generator for applying a bias voltage (V.sub.T) of a sin wave between a sample and probe, an I-V converter for converting a tunnel current flowing when the probe is set close to the sample, to a tunnel current representing voltage singal (I.sub.T), a detector for detecting the absolute value of the voltage signal (I.sub.t), and a servo circuit for servo-controlling a distance between the sample and probe using the absolute value with the servo time constant set larger than five times the period of the bias voltage. The information concerning the unevenness of the sample is obtained based on an output of the servo control means. A unit is provided for effecting the analog operation to derive a differential conductance based on the tunnel current on the real time basis and measuring the unevenness data and differential conductance between the sample and probe kept constant.
摘要:
A scanning tunneling potentio-spectroscopic microscope, includes a conductive probe and a circuit for selectively applying one of first, second and third bias voltages to a sample. A tunnel current flowing between the probe and sample is detected, and a tunnel current signal is produced upon detection thereof. A servo circuit controls a distance between the probe and sample on the basis of the tunnel current signal by producing a servo signal as a feedback signal. A hold circuit switches the servo circuit between operating and non-operating states. Configuration data on a surface of the sample is obtained, on the basis of the servo signal, with the first bias voltage applied to the sample and with the servo circuit in the operating state. A first dependence of the tunnel current on the bias voltage is obtained, from the tunnel current signal and the second bias voltage, with the second bias voltage applied to the sample and with the servo circuit in the non-operating state. A second dependence of the tunnel current on the bias voltage is obtained from the tunnel current signal and the third bias voltage, with the third bias voltage applied to the sample and with the servo circuit in the non-operating state. Electron state data is obtained on the basis of the first dependence, and potential data is obtained on the basis of the first and second dependencies.
摘要:
A bias voltage U.sub.B including a sine-wave voltage U.sub.T sin.omega. .sub.o t and an off-set voltage U.sub.REG is applied to an electrode on a sample. A potential U.sub.1 of the electrode is represented by: U.sub.1 =U.sub.REG +U.sub.T sin.omega. .sub.o t. A voltage including the bias voltage U.sub.B and a voltage .DELTA.U is applied to an electrode on the sample. A probe is approached to the sample by several nm, and a tunnel current I.sub.T flows therebetween. And the probe scans the surface of the sample. During the scan, the position of the probe is servo-controlled in the z-direction, to make constant the average absolute value of the tunnel current. The servo voltage is recorded thereby obtaining an STM image. Given that the potential difference between the electrode and a surface portion facing the probe is U.sub.S (x), the average of U.sub.1 +U.sub.S (x) becomes zero when the average of the tunnel current I.sub.T is zero. Accordingly, =0, that is, U.sub.S (x)=-U.sub.REG. Thus, by recording-U.sub.REG the potential distribution U.sub.S (x) on the sample surface is determined. Spectroscopic data is obtained by an analog operation unit, on the basis of a differential conductance .differential.I.sub.T /.differential.U.sub.T calculated from the tunnel current signal I.sub.T and the bias voltage U.sub.T.
摘要:
A scanning type tunnel microscope comprises a sample holding member for supporting a sample and a scanning probe which is arranged to face the sample to be separated therefrom by a very small distance and a supported by a scanning probe holding member. A tunnel current is flowed between the sample and scanning probe upon application of a voltage thereacross. A first actuator is coupled to the sample holding member and a second actuator is coupled to the scanning probe holding member so that the first and second actuators relatively drive said sample and said scanning probe in an axial direction and in a planar direction through said sample holding member and said scanning probe holding member. A differential micrometer is connected to the first actuator to move the actuator in the axial direction, and the micrometer and the second actuator are fixed on a substrate.
摘要:
A scanning probe microscope comprises a cantilever having a conductive probe positioned near a sample, an actuator for moving the sample to and away from the probe, a circuit for applying a bias voltage between the probe and sample to produce a tunnel current therebetween, a circuit for detecting the produced tunnel current, a circuit for detecting the amount of displacement of the probe resultant from interatomic forces acting between atomics of the probe and sample, thereby producing signals, a circuit for providing the actuator for feedback in response to the output signals from the circuit to retain constant the distance between the probe and sample, thereby causing the actuator to move the sample, a circuit for forming an STS image data from the detected tunnel current, a circuit for forming an STM image data from the detected tunnel current, and a circuit for forming an AFM image data. Thus, the STS, STP and AFM images are separately obtained simultaneously.
摘要:
A bioabsorbable release-sustaining pharmaceutical formulation using a biodegradable release-sustaining base material which can prevent an effective component drug from being released too rapidly just after administration of the formulation and then allow continued release of the drug for at least one month at a defined rate, is provided. For the biodegradable release-sustaining base material, a lactic acid-glycolic acid copolymer (PLGA) with an adjusted distribution in molecular weight is used.
摘要:
An a.c. elevator of the invention has a commercial power source (1), an inverter (3) operable with the power from the commercial power source (1) for generating a.c. power, and an electric motor to be driven with the a.c. power generated by the inverter (3). A power source device includes a rechargeable battery (E), a power source circuit (10) for charging and discharging the battery (E), and a control circuit (9) for controlling the voltage to be input to the inverter (3) by controlling the operation of the power source circuit (10). The battery (E) is charged with regenerative power from the motor, the power generated by the battery (E) is supplied to the inverter (3).
摘要:
An air cleaning apparatus such as a clean room or the like having an air circulation mechanism which circulates the humidity controlled air through a predetermined air circulation path, wherein the air circulation path is provided with a filter which has a hydrophobic zeolite layer formed on its base filter media surface and another filter which is disposed downstream from the filter having a hydrophobic zeolite layer and is used for removing particulate impurities contained in the circulating air. According to this air cleaning apparatus, gaseous organic impurities and particulate impurities contained in the air circulating in the air cleaning apparatus can be removed without lowering the humidity of the circulating air. Furthermore, since this air cleaning apparatus includes no activated charcoal which is inflammable, the apparatus is excellent from the standpoint of disaster prevention. Accordingly, the filters according to the invention and particle filters can be installed with safety in the ceiling portion of the air cleaning apparatus.