Abstract: A genetically engineered strain having high-yield of L-valine is disclosed. Starting from Escherichia coli W3110, an acetolactate synthase gene alsS of Bacillus subtilis is inserted into a genome thereof and overexpressed; a ppGpp 3?-pyrophosphate hydrolase mutant R290E/K292D gene spoTM of Escherichia coli is inserted into the genome and overexpressed; a lactate dehydrogenase gene ldhA, a pyruvate formate lyase I gene pflB, and genes frdA, frdB, frdC, frdD of four subunits of fumaric acid reductase are deleted from the genome; a leucine dehydrogenase gene bcd of Bacillus subtilis replaces a branched chain amino acid transaminase gene ilvE of Escherichia coli; and an acetohydroxy acid isomeroreductase mutant L67E/R68F/K75E gene ilvCM replaces the native acetohydroxy acid isomeroreductase gene ilvC of Escherichia coli. Furthermore, the L-valine fermentation method is improved by using a two-stage dissolved oxygen control. The L-valine titer and the sugar-acid conversion rate are increased.

Abstract: A generating device of simulating a particulate environment for an experimental animal includes an experimental chamber. An ultrasonic atomization device is installed at the bottom adjacent to the center of the experimental chamber. The upper side of the ultrasonic atomization device is connected to a guide device for guiding particles. The guide device includes an air seal cover, and a micro fan is installed inside the air seal cover to drive the movement of particles generated in the ultrasonic atomization device. Air guide pipes are fixedly connected to a side wall of the air seal cover. The generating device has good sealing performance, and can generate a variety of particle simulation environments to accurately and effectively simulate the biological effect of particles in the animal body. The generating device can improve the particle simulation environment, reduce the deviation of experimental data, and ensure the accuracy of the overall experimental data.

Abstract: The present disclosure discloses a method of preparing a Ni active site-loaded C—Si aerogel catalyst, and a product and use thereof, belonging to the technical field of catalyst preparation. The method includes the following steps: (1) dissolving absolute ethanol, trimethoxymethylsilane, cetyltrimethylammonium bromide and HCl in deionized water, conducting hydrolysis to obtain a hydrolyzate, followed by adjusting a pH value of the hydrolyzate to 7 to 8.5, and drying to obtain a C—Si aerogel; and (2) in the absolute ethanol, mixing NiCl2.6H2O with the C—Si aerogel obtained in step (1) uniformly, and conducting ultrasonication, impregnation and drying, followed by calcination to obtain the Ni active site-loaded C—Si aerogel catalyst. In the present disclosure, the prepared Ni active site-loaded C—Si aerogel catalyst is capable of conducting catalytic degradation of aromatic volatile organic compounds (VOCs) at room temperature.

Abstract: Disclosed is an atomic-scale processing method by combining extreme ultraviolet light and plasma. The method includes synergistically applying extreme ultraviolet (EUV) light and plasma to treat a surface of a material, enabling atomic-scale processing of the surface of the material.

Abstract: The present disclosure provides a low-molecular mass organic gellant and a preparation method and use thereof, belonging to the technical field of gelled fuels. The low-molecular mass organic gellant has a cyclopropane structure. The cyclopropane structure belongs to a high-tension structure, which endows the gellant with excellent gel properties; in addition, the high-tension cyclopropane structure is also capable of greatly improving a combustion performance of the gellant, shortening an ignition delay time of the fuel, and promoting combustion. Moreover, multiple hydroxyl groups contained in the low-molecular mass organic gellant is capable of effectively forming a gel through hydrogen bonding; therefore, the gellant has excellent gel and shear thinning properties for high-energy density fuel and energetic nanofluid fuel, with a critical gellant concentration of not greater than 1% when forming a stable gel.

Abstract: A learning-based active surface model for medical image segmentation uses a method including: (a) data generation: obtaining medical images and associated ground truths, and splitting the sample images into a training set and a testing set; (b) raw segmentation: constructing a surface initialization network, parameters of the network trained by images and labels in the training set; (c) surface initialization: segmenting the images by the surface initialization network, and generating the point cloud data as the initial surface from the segmentation; (d) fine segmentation: constructing the surface evolution network, the parameters of the network trained by the initial surface obtained in step (c); (e) surface evolution: deforming the initial surface points along the offsets to obtain the predicted surface, the offsets presenting the prediction of the surface evolution network; (f) surface reconstruction: reconstructing the 3D volumes from the set of predicted surface points set to obtain the final segmentatio

Abstract: A method for planar transformer with an odd turn ratio includes: determining a turn ratio and winding parameters of a transformer to be manufactured; if the turn ratio is odd, determining that there is respectively one winding turn on a first middle layer and a second middle layer and two winding turns on a top layer and a bottom layer; determining widths of winding wires on marginal layers as well as widths of winding wires on middle layers; winding and parallelly connecting an inner winding wire on the top layer to an inner winding wire on the bottom layer, and then serially connecting the parallel-connected inner winding wires to an outer winding wire to form a primary winding; and parallelly connecting the winding wire on the first middle layer to the winding wire on the second middle layer to form a secondary winding, so as to obtain the transformer.

Abstract: The invention discloses an islanding detection method in DC microgrids based on MPPT trapezoidal voltage disturbance. The steps are as follows: start the MPPT strategy; set the starting signal threshold of disturbance; measure the output current of PVA at the maximum power; calculate the same environmental factor of PVA with different capacities under the same light intensity and temperature in real time; when the environmental factor is greater than the starting signal threshold of the disturbance, periodic trapezoidal disturbance is carried out to the PVA port voltage reference; if the PCC voltage Upcc exceeds the threshold set by the passive method, it is judged as islanding; otherwise, it is judged whether the change rule of Upcc is consistent with the change rule of the calculated PCC voltage Upccp under the trapezoidal disturbance; If it is consistent, it is judged as islanding; otherwise, it is pseudo islanding.

Abstract: An alkaline protease mutant, and a gene, engineered strain, a preparation method and application thereof are provided. The method comprises the following steps of extracting genome DNA of Bacillus clausii, performing PCR amplification to obtain a wild-type alkaline protease gene sequence, mutating the wild-type alkaline protease gene obtained by the amplification through an error-prone PCR, performing high-throughput screening to obtain a plurality of highly active alkaline protease genes, performing DNA shuffling on the highly active alkaline protease genes, and performing screening to obtain eight alkaline protease mutant genes with higher activity.

Abstract: Disclosed are a drinking under influence (DUI) detection system and a DUI detection method based on an MQ3 sensor and an ultra wide band (UWB) radar. The system includes an alcohol detection module, a respiratory detection module, a signal matching module and a drunk driving alarm module, and each module cooperates to complete a detection. The MQ3 sensor-based alcohol detection module is used for alcohol signal capture, alcohol sequence processing and DUI threshold detection; the UWB radar-based respiratory detection module is used for respiratory signal capture, respiratory signal processing and passenger separation and positioning; the signal matching module is used for periodic signal alignment, sequence feature matching and drinker identity confirmation; and the DUI alarm module is used for a system alarm prompt, a data visualization interface and a DUI information uploading.

Abstract: A movable carbon capture system applied to agriculture-harmonious buildings, which includes a carbon capture unit and a high-concentration CO2 supply unit which are respectively integrated, wherein the carbon capture unit comprises a CO2 adsorption chamber and an air pump, and the high-concentration CO2 supply unit comprises a vacuum pump and an air storage cavity; an air inlet of the CO2 adsorption chamber is connected to the indoor environment, an exhaust port of the CO2 adsorption chamber is connected to an atmosphere outlet, an air outlet of the CO2 adsorption chamber is connected with an air inlet of the vacuum pump, an air outlet of the vacuum pump is connected with an air inlet of the air storage cavity, an air outlet of the air storage cavity is connected with a greenhouse air supply port, and the greenhouse air supply port is connected with a greenhouse.

Abstract: The present invention discloses a novel nano-composite antibacterial material and a preparation method and an application thereof, and belongs to the technical field of preservative materials. The novel nano-composite antibacterial material disclosed by the present invention is prepared by mixing a dimethylimidazole solution, deionized water and a zinc nitrate solution to prepare a metal-organic framework carrier, compositing with nisin to form a nano antibacterial composite material, separating out from a solution in a precipitate form, centrifuging, removing a supernatant, cleaning and re-suspending with the deionized water. The novel nano-composite antibacterial material prepared by the present invention has an antibacterial effect superior to nisin having a same concentration.

Abstract: The present application discloses a liquid seal method for on-off of gas pipeline and a device thereof, wherein a liquid-sealed U-shaped container being provided in the gas pipeline that requires to perform on-off control; a lifting mechanism using a leading screw controls the slider having a certain volume to immerse in or leave the liquid so as to raise or lower the liquid level. The U-shaped container has a structure with a wide top and a narrow bottom, the space of the U-shaped container is divided into two spaces with different sizes by a separating plate, and a liftable liquid-occupying device is located at the space having a larger volume; the upper and lower parts of the slider are tapered; and the driving device can be motor or hand wheel.

Abstract: It is provided a power generation model based on a transcritical cycle with an increasing-pressure endothermic process using CO2-based mixture working fluids for an enhanced geothermal system, including a geothermal water circulation, a mixture working fluid circulation and a cooling water circulation. A coaxial pipe-in-pipe downhole heat exchanger is provided in the mixture working fluid circulation. Innovations are reflected in that an increasing-pressure endothermic process is achieved due to making use of gravity and hence increase a heat quantity absorbed in a cycle, thereby improving power generation quantity of the cycle; and a binary mixture working fluid composed of CO2 and an organic working fluid is adopted to realize a transcritical power cycle with an increasing-pressure endothermic process and a decreasing-temperature exothermic process, thereby effectively reducing irreversibility of a heat transfer between a working fluid and a heat source and improving power cycle efficiency.

Abstract: The present disclosure relates to the field of genetic engineering, especially relates to a xylose-induced genetically engineered bacteria used for producing ectoine as well as a construction method and use thereof. The genetically engineered bacteria is constructed by heterologously expressing the ectABC gene cluster from Halomonas elongata on the E. coli chromosome, using the promoter of xylose transporter coding gene xylF to control the RNA polymerase from T7 bacteriophage, reconstructing a synthesis pathway of ectoine and constructing a plasmid-free system, and enhancing the expression of target genes by a strong promoter T7; the yield of ectoine reached 12-16 g/L after 20-28 h fermentation in shake flask, and reached 35-50 g/L after 24-40 h fermentation in a 5 L fermentor.

Abstract: A genetically engineered bacterium includes a genome of the Eschericia coli and a mutant encoding gene hisG* of a Corynebacterium glutamicum ATP phosphoribosyl transferase HisG on the genome, and the gene hisG* is strongly expressed to enhance activity of a key enzyme HisG for histidine synthesis. The gene hisG* has a nucleotide sequence as shown in SEQ ID NO: 1; a copy number of histidine operon genes hisDBCHAFI of the Eschericia coli is further increased on the genome to enhance a terminal synthetic route of histidine; an encoding gene lysE from an arginine/lysine transportprotein of the Corynebacterium glutamicum is further integrated to the genome and strongly expressed to promote the intracellular histidine secrete to the extracellular space; and an encoding gene rocG of glutamate dehydrogenase of Bacillus subtilis is further integrated to the genome and strongly expressed to promote generation of histidine.

Abstract: Provided is a p-type TiO2/n-type WO3 heterojunction catalyst and a preparation method and use thereof. The catalyst comprises p-type TiO2 and n-type WO3 supported on a surface of the p-type TiO2.

Abstract: A freely-connectable three-strut parallel orthopedic external fixator including two fixation rings and three struts, connecting holes are circumferentially and uniformly distributed on the ring surfaces of each fixation ring, each strut is provided with two driving translational pairs, a revolute pair and a spherical pair. Two fixation rings are respectively fixedly connected with the bone segments of the fracture site by using medical metal bone pins; adjusting the driving translational pairs of the six struts can achieve six DoF relative movement of the two fixation rings, thereby achieving fracture reduction. The external fixator of the present invention realizes free connection between the two fixation rings, which facilitates fixator installment; number of struts is less than the existing external fixators.

Abstract: A method for enhancing degradation of ester volatile organic compounds with a cerium oxide supported palladium single atom catalyst under low-temperature microwave comprises the steps of firstly preparing a single atom catalyst Pd/CeO2, adding the catalyst Pd/CeO2 into a reaction cavity, initiating microwave radiation to enhance the catalysis reaction, and quickly introducing an ester compound with a concentration of 50˜5000 mg/m3 and a space velocity of 2000˜100000 h?1 into the reaction cavity from a vapor phase sampling port to react when the reaction temperature is 10˜80° C. A catalyst packed column is provided in the reaction cavity, the vapor phase sampling port is defined at the bottom of the reaction cavity, and an exhaust port is defined at the top of the cavity. The microwave method can enhance and activate active sites, prevent the aging of active sites, and enable the chemical reaction rate to be increased by more than 17.9%.

Abstract: Disclosed is an intelligent circulation and allocation control system for multiple surface and ground water resources, including a physical, chemical and biological multi-stage decentralized restoration system, which is respectively connected with a water quality detection and reinjection system, an integrated data processing system, an intelligent safety early warning system, and an asynchronous and self-adaptive dual-regulation optimization control system, the water quality detection and reinjection system is connected with the intelligent safety early warning system, the intelligent safety early warning system is connected with the integrated data processing system, and the integrated data processing system is further connected with the asynchronous and self-adaptive dual-regulation optimization control system.