Abstract: The present application discloses a synthesis method of chiral nicotine from nicotinate and ?-butyrolactone, including the following steps: Step S1: performing condensation under an alkaline condition, and performing ring opening reaction with hydrochloric acid; Step S2: reacting with (+)—B-diisopinocampheyl chloroborane to produce a chiral hydroxyl group; Step S3: performing a chlorination reaction; and Step S4: performing cyclization under an alkaline condition to obtain the chiral nicotine. In the present application, nicotinate and ?-butyrolactone, both cheap and readily available, are used as raw materials, so as to reduce the production cost of (S)-nicotine. (+)—B-diisopinocampheyl chloroborane is used to reduce a carbonyl group of an intermediate to obtain a target chiral center.

Abstract: A BTA drilling quick-stop device (QSD) and a method, wherein the BTA drilling QSD includes a base. The base includes a hollow cavity. A side portion of the base has an opening communicating with the hollow cavity. The opening is closed by a through cover. A horizontally movable fixture is disposed in the hollow cavity. A stopper is disposed at a top portion of the base. A bottom portion of the stopper is disposed lower than a top portion of the fixture to stop the fixture from moving during processing. An elastic element is disposed between the through cover and a side portion of the fixture to push the fixture to move after processing.

Abstract: A method, an apparatus and a medium for optimizing allocation of switching resources in the polymorphic network. The method selects the ASIC switching chip, FPGA and PPK software switching on the polymorphic network element based on machine learning, and specifically comprises the following steps: manually pre-configuring, formulating basic rules for polymorphic software and hardware co-processing; offline learning, designing training configuration in the offline learning stage to capture different switching resource usage variables, running experiments to generate the original data of a training classifier, and using the generated performance indices to train the model offline; and online reasoning, obtaining switching resource allocation advises, and updating modality codes according to the switching resource allocation advises.

Abstract: The disclosure provides a resin cleaning device and method. The resin cleaning device includes a control system, a treatment unit, a driving unit, and a feedback assembly. The treatment unit, the driving unit, and the feedback assembly are respectively in communication connection with the control system. The treatment unit is configured for treating a member-to-be-cleaned so as to reduce a viscosity of resin on the member-to-be-cleaned. The driving unit is configured for driving the member-to-be-cleaned to rotate. The feedback assembly is configured for acquiring a position signal of the member-to-be-cleaned and feeding the position signal back to the control system, such that the control system controls the treatment unit and the driving unit according to the position signal. Through the above manner, a more intelligent resin cleaning process with a better cleaning effect may be realized.

Abstract: A method for preparing a shell-bionic ceramic tool and a shell-bionic ceramic tool, wherein the shell-bionic ceramic tool includes alternating stacks of ceramic powders with different components, pressing a ceramic green body using a cold briquetting method, carrying out pre-pressing once using a graphite indenter on a working surface thereof after each layer of the ceramic powder being loaded, and pressing a last layer using a graphite rod, and then pressing a whole ceramic green body with a certain pressure to promote a bonding of the layers of ceramic powder, which in turn gives a complex shape to an interface between the layers, increases a bonding area between the layers, and plays the role of hindering crack expansion, extending the crack expansion path, and improving the bonding strength of the interface; after then, hot-pressed sintering is used to densify the ceramic green body to obtain the shell-bionic ceramic tool.

Abstract: A support stand for photography includes a support main body having supporting ends and a mounting end and an adapting device provided at the mounting end. The supporting ends are formed on supporting legs of the support main body. The supporting legs can be unfolded to allow two adjacent supporting ends to move away from each other. The supporting legs can be folded to allow the two adjacent supporting ends to move close to each other and form a gap between two adjacent supporting legs. The adapting device includes a fixed seat provided with an adapting structure for mounting a first photographic equipment and a clamping seat configured to clamp a second photographic equipment. The clamping seat is rotatably connected to the fixed seat. The clamping seat can rotate toward a side where the supporting ends are located to be accommodated in the gap between the two adjacent supporting legs.

Abstract: Gas detection devices comprise a dehydration unit a concentration unit, and a temperature control unit for controlling a temperature. The gas detection device includes a sampling mode in which sample gas flows into and out of the dehydration unit through a first port and a second port, respectively, wherein the volatile organic compounds in the sample gas are concentrated in the concentration unit. The temperature control unit may be configured such that the temperature of the sample gas after flowing out from the dehydration unit and before flowing into the concentration unit is not greater than a first preset temperature. Generation of condensed substances in the sample gas can be effectively avoided in a simple manner after the sample gas flows into the concentration unit, thereby further preventing ice blockage. Methods for detecting volatile organic compounds in a sample gas are also disclosed.

Abstract: A nuclear emergency multifunctional operation robot includes a base, a mechanical arm, a tool change-over device, and motion supporting devices. The base includes a pedestal, a mounting seat A, a mounting seat B, a mounting seat C, a rotation driving mechanism A, and a rotation driving mechanism B. The front end of the mechanical arm is connected to the mounting seat B; the tool change-over device includes a male connector and a female connector which are abutted with or separated from each other; and the motion supporting devices are used to drive the nuclear emergency multifunctional operation robot to move. The present disclosure has the advantages that the base can be integrated with various end tools, so that the operation robot conveniently changes over tools according to operation needs to conduct various types of operations.

Abstract: The technology of this application relates to a data read/write apparatus and an electronic device, which relate to the data storage field, and can improve data read/write performance. The data read/write apparatus includes a first laser, configured to output a first optical pulse based on a control signal, where the control signal is a signal obtained based on to-be-written data, a dispersion compensator, configured to perform dispersion compensation on the first optical pulse to output a second optical pulse, and an optical fiber lens, connected to the dispersion compensator by using an optical fiber, and configured to focus the second optical pulse onto an optical storage medium, to write the to-be-written data to the optical storage medium.

Abstract: An alumina-based ceramic tool material with low thermal expansion and a preparation process thereof, accordingly, the ceramic tool material may have both the high hardness of alumina ceramics after the hot pressing sintering, and reduces the thermal expansion coefficient of the overall ceramic material by adding the Sc2W3O12 as the negative thermal expansion phase, which improves the thermal shock resistance of ceramic tools in high-speed cutting engineering and meets the requirements of large temperature range during the machining of nickel-based superalloys. Moreover, the composite material does not use metal binder and has strong thermal stability even in the high-speed machining under extreme heat-force-chemistry coupling, so it has a high machining compatibility for nickel-based superalloys.

Abstract: An aluminum borate whisker reinforced and toughened non-metallic matrix composite is provided, which specifically includes a non-metallic material reinforced and toughened with aluminum borate whiskers. The composite exhibits a higher bending strength and fracture toughness and a higher wear resistance. A method for preparing the composite is also provided. The method includes mixing the aluminum borate whiskers and the non-metallic material to form a mixture; and sintering the mixture by a vacuum hot press method, or molding the mixture.

Abstract: A planar transformer includes a magnetic core. The magnetic core includes a first magnetic core cover, a second magnetic core cover, n first magnetic core pillars, and k second magnetic core pillars, the n first magnetic core pillars and the k second magnetic core pillars are disposed between the first magnetic core cover and the second magnetic core cover, and n and k each are an integer greater than 0. A primary-side winding and a secondary-side winding that are coupled to each other are disposed on each of the n first magnetic core pillars, and an auxiliary inductor winding is disposed on each of the k second magnetic core pillars.

Abstract: An acoustic garbage classification method using a one-dimensional convolutional neural network (1D-CNN) is provided. The method includes: acquiring sound signals generated by falling garbage; preprocessing the sound signals; acquiring and preprocessing the sound signals of different types of garbage, building a sound database for garbage classification, and establishing and training a 1D-CNN model; acquiring a sound signal of garbage to be classified, and inputting the sound signal into the trained 1D-CNN for garbage classification to obtain a classification result. The present disclosure is helpful to assist people in accurate garbage classification, improves the accuracy of garbage classification and recycling, and has high practical and popularization value.

Abstract: Provided is an extension module for independently storing calibration data, including: a first interface, adapted to receive a first external input signal; a second interface, adapted to output the first output signal of the extension module; a signal processing circuit, connected between the first interface and the second interface; and a first memory, the first memory storing first calibration data, and the first calibration data being associated with the extension module. Furthermore, also provided is a component using the above extension module, and a component calibration method. On the one hand, the extension module of an embodiment may share an ADC sampling circuit on a main module, so that the manufacturing cost of the extension module is reduced. On the other hand, an embodiment can facilitate the replacement of different extension modules for the main module without repeated calibration.

Abstract: A method for detecting an object includes obtaining an original image of a road through a sensor by performing an image capturing operation; extracting a region of interest (ROI) including a first target pixel point from the original image, in which the first target pixel point is a pixel point in the original image corresponding to a position on the road that is farthest from the sensor; and generating an object detection result by performing object detection on the ROI.

Abstract: Biological research requires isolation and analysis of material, for example, RNA, DNA and protein, from tissue samples. The methods and compositions described herein allow for high resolution imaging of large and intact tissue samples, and subsequent isolation of material in a precise and location dependent-manner. The methods and compositions described herein may be used, for example, for biomarker discovery, identification of cell populations, pathology analysis, and generation of expression data in specific regions of interest.

Abstract: The present application provides a preparation method for synthesizing a chiral nicotine from a chiral tert-butylsulfenamide, which includes steps as follows: condensating 3-pyridinecarboxaldehyde with tert-butylsulfenamide at the presence of a titanate; and then reacting (1,3-dioxane-2-yl ethyl) magnesium bromide; cyclizing under an acidic condition; finally obtaining chiral nicotine after reduction and amine methylation.

Abstract: The present application provides a preparation method of racemic nicotine, including the following steps: Nicotinyl chloride and methylamine are reacted under alkaline conditions to obtain methylnicotinamide, then condensed with monochloroacetone to obtain N-methyl-N-(2-oxopropyl) nicotinamide, then self-aldol condensed to obtain 1-methyl-5-(pyridin-3-yl)-1,2-dihydro-3H-pyrrol-3-one, and finally reduced to obtain racemic nicotine.

Abstract: The present application discloses a synthesis method of chiral nicotine from nicotinate and ?-butyrolactone, including the following steps: Step S1: performing condensation under an alkaline condition, and performing ring opening reaction with hydrochloric acid; Step S2: reacting with (+)-B-diisopinocampheyl chloroborane to produce a chiral hydroxyl group; Step S3: performing a chlorination reaction; and Step S4: performing cyclization under an alkaline condition to obtain the chiral nicotine. In the present application, nicotinate and ?-butyrolactone, both cheap and readily available, are used as raw materials, so as to reduce the production cost of (S)-nicotine. (+)-B-diisopinocampheyl chloroborane is used to reduce a carbonyl group of an intermediate to obtain a target chiral center.