Abstract: Disclosed is a method for pretreating Ranitidine hydrochloride sample, comprising steps: S1, weighing the Ranitidine hydrochloride sample containing an impurity of N-nitrosodimethylamine; S2, preparing a test solution of Ranitidine hydrochloride so that the concentration of N-nitrosodimethylamine in the test solution reaches the detection limit of high-performance liquid chromatography; S3, adding an alkaline solution to the Ranitidine hydrochloride test solution, wherein the alkaline solution reacts completely with hydrochloric acid in Ranitidine hydrochloride to give a Ranitidine neutralizing solution; S4, adding a silver ion solution to the Ranitidine neutralizing solution, and silver ions undergo a complete complexation reaction with secondary amino groups in Ranitidine to generate a precipitate.

Abstract: A method for automatic adjustment of a power grid operation mode based on reinforcement learning is provided. An expert system for automatic adjustment is designed, which relies on the control sequence of thermal power units, enabling automatic decision-making for power grid operation mode adjustment. A sensitivity matrix is extracted from the historical operating data of the power grid, from which a foundational thermal power unit control sequence is derived. An overload control strategy for lines within the expert system is devised. A reinforcement learning model optimizes the thermal power unit control sequence, which refines the foundational thermal power unit control sequence and provides the expert system with the optimized control sequence for automatic decision-making in power grid operation mode adjustment. This method offers a solution to balancing and absorption challenges brought about by fluctuations on both the supply and demand sides in high-proportion renewable energy power systems.

Abstract: A cable tension calculation method simultaneously considering the sag, inclination angle and bending stiffness includes: querying basic parameters of a stay cable according to design data and construction data; considering influences of the sag, the inclination angle ? and the bending stiffness EI, to calculate dimensionless parameters ?, ? and ?2; testing an acceleration response of the stay cable by an acceleration sensor, to identify a frequency ? of the acceleration response of the stay cable, further calculating a dimensionless frequency {circumflex over (?)} of the stay cable and the dimensionless parameters ?, ? and ?2, and substituting the dimensionless frequency {circumflex over (?)} of the stay cable into a vibration characteristic equation, to establish a function relation between the dimensionless frequency {circumflex over (?)} and a cable tension H* of the stay cable; and solving a root of the vibration characteristic equation, and identifying the cable tension H* of the stay cable according to

Abstract: A motion estimation method and a system in inter-frame prediction coding of 3D point cloud data: first, isometric sub-sampling is performed for points in pc_likely_world, then, the sampled points were divided into uniform small cubes, and the centroid of point cloud location information in each small cube was calculated, and the points closest to the centroid were found, and these points were put into pc_world_target. Finally, the corresponding point pc_world_ref is found in the reference frame, and the LMS algorithm is used to calculate the global motion matrix; by reserving the centroid points in each block, the method not only effectively removes the redundant points to reduce the computational complexity of the global motion matrix but also preserves the points that represent the characteristics of the point cloud to ensure the computational accuracy of the global motion matrix.

Abstract: A microscope includes: an electronic optical column configured to emit scanning electron beams; a specimen stage configured to place a specimen; a target movably disposed between the electronic optical column and the specimen stage; and a driving mechanism for driving the target to move between a first position and a second position, wherein the first position is a position at which the electron beams act on the specimen, and the second position is a position at which the electron beams act on the target to generate X-rays irradiating the specimen. In the present disclosure, through one time mounting of the specimen, the microscope enables the dual-function detection of the specimen, i.e., detection of the specimen by an SEM and detection of the specimen by a Nano-CT.

Abstract: A method for determining information, a remote terminal, and a mower are provided. The method includes: collecting a to-be-processed image for a to-be-recognized region through an image collector of a to-be-controlled device, where the to-be-recognized region at least includes a to-be-processed region and an obstacle region; processing the to-be-processed image, and determining information of a partial boundary of a to-be-processed region where the to-be-controlled device is currently located; and controlling the to-be-controlled device to switch between an autonomous movement mode and a remotely controlled movement mode based on the information of the partial boundary to determine a boundary of the to-be-processed region, where the boundary of the to-be-processed region is used for distinguishing the to-be-processed region from the obstacle region. The method can solve the problems of cumbersome operations and low efficiency existing in existing methods for determining a regional boundary.

Abstract: Provided is an electron beam system, including: an electron source, configured to generate an electron beam; a first beam guide, configured to accelerate the electron beam; a second beam guide, configured to accelerate the electron beam; a first control electrode arranged between the first beam guide and the second beam guide, configured to change movement directions of backscattered electrons and secondary electrons generated by the electron beam acting on a specimen to be tested; a first detector arranged between the first beam guide and the first control electrode, configured to receive the backscattered electrons generated by the electron beam acting on the specimen to be tested.

Abstract: A camera module includes a circuit board, a photosensitive chip, a filter, a l holder, and a lens assembly. A receiving groove is recessed from a surface of the circuit board. The photosensitive chip is received in the receiving groove. The holder is mounted on the surface of the circuit board and covers the photosensitive chip. The filter is mounted in the holder and spaced from the photosensitive chip. The lens assembly is mounted on the holder and located at a side of the filter facing away from the photosensitive chip. A dustproof layer is laid on the surface of the circuit board facing the filter and surrounds the photosensitive chip. An electronic device having the camera module is also provided.

Abstract: The application provides a speaker device having a housing and sounding unit. The housing includes an upper housing and a lower housing. A containment space for accommodating the sounding unit is arranged between the upper housing and the lower housing. The sounding unit includes a vibration diaphragm separating the containment space into a front vocal cavity and a rear cavity. A sound conduction channel is provided to connect to the front vocal cavity with the outside world. A pressure relieving hole is communicated with the front vocal cavity. The speaker device can transmit the sound from the sounding unit in the containment space to the outside through the sound conduction channel. The pressure relieving hole can improve the pressure relief ability of the front vocal cavity, thereby improving the distortion of the speaker device and improving the sound quality.

Abstract: A thinned lens module with high imaging quality comprises a base, an optical filter, and a metal sheet. The base defines a first receiving groove and a second receiving groove communicating with the first receiving groove. The metal sheet is received in the first receiving groove and fixed to a sidewall of the first receiving groove. The optical filter is received in the second receiving groove and fixed on the metal sheet. An electronic device including the lens module is also disclosed.

Abstract: A motion estimation method and a system in inter-frame prediction coding of 3D point cloud data: first, isometric sub-sampling is performed for points in pc_likely_world, then, the sampled points were divided into uniform small cubes, and the centroid of point cloud location information in each small cube was calculated, and the points closest to the centroid were found, and these points were put into pc_world_target. Finally, the corresponding point pc_world_ref is found in the reference frame, and the LMS algorithm is used to calculate the global motion matrix; by reserving the centroid points in each block, the method not only effectively removes the redundant points to reduce the computational complexity of the global motion matrix but also preserves the points that represent the characteristics of the point cloud to ensure the computational accuracy of the global motion matrix.

Abstract: Example interface information presenting methods, electronic devices and computer-readable storage media are provided. An example method includes: obtaining a target interface; in response to a first operation of a user, entering a screen-locked state, and obtaining a first picture displayed in the screen-locked state; processing the target interface to obtain a target picture; and displaying the target picture in the screen-locked state, to cover the first picture.

Abstract: Method, apparatus and computer program product for dynamic link processing engine. For example, the apparatus includes at least one processor and at least one non-transitory memory including program code.

Abstract: The present application relates to the technical field of architectural engineering. Disclosed are a slab joint leakage-proof structure of a prefabricated roof panel, a prefabricated roof panel and a prefabricated roof panel system. The slab joint leakage-proof structure comprises a first leakage-proof layer. The first leakage-proof layer comprises two flexible structures which abut against each other and are arranged at the joint of a main rib on the long side of the roof panel and a main rib on the long side of an adjacent roof panel. Either of the flexible structures comprises a main body portion sealably attached to the main rib, and at least one protruding portion which is fixedly disposed on the main body portion, protrudes and extends into the joint, and can tightly abut against the other flexible structure. The protruding portions of the two flexible structures can enclose an air cavity layer sealably isolated from the outside.

Abstract: The present invention provides a speaker, including: a housing body having an accommodation cavity with a first chamber and a second chamber; a first side wall and a second side wall enclosing the first chamber; a third side wall and a fourth side wall enclosing the second chamber; and a speaker unit including a connection part located in the first chamber and a sounding component connecting to the connection part. A distance between the first side wall and the second side wall is smaller than a distance between the third side wall and the fourth side wall. The speaker enables the connection part to be connected to the side wall of the housing body without the end of the connection part needing to exceed the end of the sounding component, which reduces the volume of the housing body and facilitates the miniaturized design of the speaker.

Abstract: A speaker includes a housing having a receiving space, a speaker unit and a cavity received in the receiving space, sound-absorbing particles filled in the filling cavity, a filling hole opened in the housing and communicating with the filling cavity for filling the sound-absorbing particles into the filling cavity, a hole cover covering the filling hole and a resilient member filled in the filling hole. The resilient member can deform in the height direction of the filling hole, and the resilient member is sandwiched in a compressed state between the hole cover and the sound-absorbing particles. Compared with the related art, the sound-absorbing particles of the speaker disclosed by the present disclosure are not easily damaged.

Abstract: A speaker includes a frame with a leakage hole, a magnetic circuit system and a vibration system received in the frame and a mesh covering the leakage hole. The vibration system comprises a diaphragm and a coil. The magnetic circuit system comprises a lower clamp and a magnet assembly stacked on the lower clamp. The mesh is integrally injection-molded with the frame, and comprises a central portion opposite to the leakage hole and a fixed portion located around the central portion and fixed with the frame. The fixed portion comprises an embedded portion embedded in the frame. The frame comprises a cover portion covering the embedded portion. The cover portion is provided with a recessed portion recessed from the surface of the cover portion away from the embedded portion toward the embedded portion until in contact with the embedded portion.

Abstract: The present disclosure is related to genetically engineered microbial strains and related bioprocesses for the production of products from acetyl-CoA. Specifically, the use of dynamically controlled synthetic metabolic valves to reduce the activity of certain enzymes, leads to increased product production in a two-stage process.

Abstract: Example bullet screen play methods and apparatus are described. One example bullet screen play method includes receiving a bullet screen enabling instruction for a target video, where the bullet screen enabling instruction instructs to play a bullet screen in a virtual reality (VR) bullet screen manner. An annular transparent bullet screen layer is drawn in a preset orientation of a video layer of the target video in response to the bullet screen enabling instruction, where a first height of the video layer is less than a second height of the bullet screen layer. Bullet screen information of a real-time bullet screen of the target video is obtained. Three-dimensional coordinates of the real-time bullet screen on the bullet screen layer are calculated based on the bullet screen information. The real-time bullet screen is refreshed and played on the bullet screen layer based on the three-dimensional coordinates.