71results about How to "Easy to realize engineering application" patented technology

The invention discloses a common-light-path type multiple inclined wave surface compensation nonzero-digit interference measurement device which comprises a Fizeau interferometer, a standard optical flat, a free-form surface gradient compensation module and a free-form surface to be measured. A primary optical axis of the free-form surface gradient compensation module coincides with a primary optical axis of the interference measurement device, a parallel light beam emitted by the Fizeau interferometer passes through the standard optical flat and is divided into two light beams, one light beam is reflected by the surface of the standard optical flat back to the Fizeau interferometer to be used as reference light, the other light beam enters in the free-form surface gradient compensation module and is emitted out of the free-form surface gradient compensation module, and testing light beams with different inclined angles are formed to irradiate the free-form surface to be measured in an incident mode, are reflected by the free-form surface to be measured back to the free-form surface gradient compensation module, finally are emitted out of the free-form surface gradient compensation module and return to the Fizeau interferometer to form test light. According to the test, high-precision measurement on the optical free-form surface large in local gradient and transportability modularization on the measurement device are achieved simultaneously.

The invention discloses a method for modifying nano iron particles on the surface of cellulose. The invention uses two kinds of environment-friendly, non-toxic, harmless cellulose as dispersants, and in the preparation process of the nano iron particles, the surface of the particles is surface-treated. Modified and modified, the prepared cellulose dispersant modified nano iron particles. The process of the invention is simple and easy to operate, low in cost, and has good dispersibility of the nano-iron particles, which can reduce the agglomeration of the particles in water and improve the removal efficiency of the particles to organic pollutants, dyes, pesticides, nitrates and heavy metals.

The invention provides a rare earth magnesium alloy, which is a modified Mg-Gd-Y-Zr rare earth magnesium alloy; the as-cast metallographic structure of the rare earth magnesium alloy has rounded edges Mg 5 Gd phase; or, the metallographic structure of the rare earth magnesium alloy in the extruded state has small particle-like precipitates; the radial size of the small particles is 10-150 nm. The invention improves the microstructure and morphology of the alloy through the method of multi-element microalloying, improves the microstructure and morphology of the alloy material by adding a specific proportion of trace Ag and Sc, and improves the effect of age hardening and grain refinement, thereby obtaining excellent room temperature and temperature. High temperature mechanical properties. On the premise of not increasing the total amount of rare earths, the present invention has high strength and performance indexes, retains good plasticity, is easy to realize engineering application, and can meet the requirements for lightweight structural materials in the current aerospace, missile military, rail transit and other fields. Requirements for mechanical properties at room temperature and high temperature.

The invention discloses a novel positive sequence impedance differential protection method of a microgrid. The method comprises the following steps of acquiring a three-phase current and a three-phase voltage in real time, and further calculating positive sequence impedance at a protection installation position; carrying out calculation of action impedance and braking impedance; judging whether a differential protection region is a fault section or not by a local-side protection device after receiving positive sequence impedance information of an opposite side of the differential protection region through a communication network; and additionally arranging a phase-comparison distance component in a detection blind region subjected to the positive sequence impedance differential protection for identifying a three-phase metal fault. The method can be suitably used for two running states of grid connection and island of the microgrid, the influence of through current and large transition resistance on fault detection during a fault is fully considered, moreover, the method is implemented without the assistance of synchronous signal acquisition and a fault component, the complicated network structure of the microgrid and the problem brought to microgrid protection by variable running states are effectively solved, and the protection selectivity and reliability are ensured.