Abstract: A system for monitoring rock damage in deep engineering environment includes an acoustic emission sensor assembly and an acoustic emission amplifier assembly. The assemblies are mounted on a rock mechanics test system. The acoustic emission sensor clamp includes a coupling screw, as well as a clamp cover, a clamp cylinder, and a coupling panel threadedly connected in sequence. The acoustic emission amplifier assembly includes an acoustic emission amplifier, an upright column having a guide rail, a lifting support plate, and a support plate lifting oil cylinder. Additionally, an evaluation method based on acoustic emission tempo-spatial evolution laws is presented. According to the properties of acoustic emission, fractal characteristics of damage evolution processes of rock test pieces are analyzed and the relationship between stress, energy and fractal dimension in the whole process of tensile deformation damage of the rock test pieces is obtained.

Abstract: A functional ink suitable for 3D printing and a preparation method thereof are provided. The ink includes the following components in parts by weight: 0.5-1.5 parts of a regulator, 1-5 parts of a conductive material, 0.1-0.5 parts of a crosslinking agent, 0.1-0.5 parts of a catalyst, and 10-80 parts of a solvent. The prepared functional ink has a self-healing function at room temperature, eliminating the interface resistance between printing layers and improving the mechanical strength between the layers. Moreover, the prepared functional ink has excellent electrical conductivity and a variety of electrical, magnetic, and electrochemical properties, and can be applied in the fields of functional materials and devices such as energy storage, electromagnetic shielding and stress sensing.

Abstract: A moon-based in-situ condition-preserved coring multi-stage large-depth drilling system and method therefor. The system includes a rotary plate provided inside a lander, an in-situ condition-preserved coring tool provided on a surface of the rotary plate, a space frame provided on a surface of the rotary plate, a working platform provided on a top of the space frame, a mechanical arm provided on a bottom surface of the working platform, and a camera provided on the bottom surface of the working platform, the mechanical arm is fixedly connected to the working platform, and the camera is fixedly connected to the working platform. By controlling the mechanical arm to place the in-situ condition-preserved coring tool on the moon surface, and using the in-situ condition-preserved coring tool to sample the lunar soil on the moon surface, the coring operation problem of the lunar soil is solved.

Abstract: An AFI-CHA hybrid crystal molecular sieve and an NH3-SCR catalyst using the AFI-CHA hybrid crystal molecular sieve as a carrier, and preparation methods thereof are disclosed. The AFI-CHA hybrid crystal molecular sieve includes an AFI-type SAPO-5 molecular sieve and a CHA-type SAPO-34 molecular sieve, with hybrid crystal grains of AFI and CHA. The hybrid crystal molecular sieve is synthesized by a hydrothermal synthesis method and can be obtained by changing the structure directing agent, the heating rate and the calcinating temperature in the preparation process. Further, copper is loaded on the basis of the hybrid crystal molecular sieve to prepare copper-based NH3-SCR catalyst and corresponding monolithic catalyst. The catalytic activity and hydrothermal stability of the catalyst are significantly improved by the hybrid crystal molecular sieve.

Abstract: A loading platform for a rock mechanics test system (MTS) to realize simple and reliable connection between a high temperature and high pressure force sensor in a triaxial chamber cavity and an upper solid rigid column. The loading platform for rock mechanics test includes a master rod, a secondary rod and a stop sleeve sleeved on the master rod; the stop sleeve is provided with two corbel structures; the secondary rod is composed of a secondary rod head body and a secondary rod body; a circular magnetic block is fixed on the secondary rod to adsorb a hole alignment sleeve sleeved on the secondary rod; and the hole alignment sleeve marked with a first scale line and a second scale line.

Abstract: A few-shot learning based intrusion detection method of an industrial control system, including: dividing an original data set extracted from a data flow of the industrial control system into a detection model training set and a basic model training set; using principal component analysis method to reduce dimension of a continuous data matrix M in the two training sets; using one-hot encoding method to process a discrete data matrix V in the two training sets; using processed basic model training set to construct few-shot training tasks required for basic model training; training a basic model based on convolutional neural networks with help of constructed few-shot training tasks; based on trained basic model, using processed detection model training set for further training to obtain the detection model; effectively detecting attacks in real-time data streams with help of center vectors of three different types of samples in the detection model.

Abstract: A functionally gradient material for guided periodontal hard and soft tissue regeneration includes a 3D printed scaffold layer and an electrospun fibrous membrane layer. The content of hydroxyapatite in the 3D printed scaffold layer is higher than the content of hydroxyapatite in the electrospun fibrous membrane layer. The pore size of the 3D printed scaffold layer is larger than the pore size of the electrospun fibrous membrane layer. The pore size of the 3D printed scaffold layer is 100-1000 ?m, and the fiber diameter of the electrospun fibrous membrane layer is 300-5000 nm. The electrospun fibrous membrane layer is in a random distribution or an oriented arrangement or has a mesh structure. The thickness of the electrospun fibrous membrane layer is 0.08-1 mm.

Abstract: A T-type DC circuit breaker includes a main branch, a first commutation switch, a second commutation switch, and a bypass branch. The first commutation switch and the second commutation switch are arranged at both ends of the main branch, respectively. The bypass branch is connected in parallel with the main branch. The main branch includes at least one half-controlled power electronic component. The bypass branch includes a bypass capacitor and a bypass diode connected in series. Each of the first commutation switch and the second commutation switch includes at least one fully-controlled power electronic component. The first commutation switch is connected in parallel with a first surge arrester, and the second commutation switch is connected in parallel with a second surge arrester. The grounded branch is arranged between the main branch and the second commutation switch and is grounded or connected to the negative terminal of the load.

Abstract: An N-substituted imidazole carboxylate compound is of formula (I). In formula (I), C* is an R-type chiral carbon atom, R1 and R2 are independently selected from H, methyl, ethyl, cyclopropyl, cyclobutyl or isopropyl, or R1 and R2 form a C2˜5 alkylenyl group; R3 is a substituted or unsubstituted C1-18 saturated or unsaturated aliphatic hydrocarbon or aromatic hydrocarbon, in which the aliphatic hydrocarbon comprises a straight chain, branched chain or cyclic aliphatic hydrocarbyl. The compound or pharmaceutically acceptable salts thereof can be used to prepare central inhibitory drugs that exert sedative, hypnotic and/or anesthetic effects on humans or animals, and can produce rapid and reversible anesthetic effects, and can be rapidly metabolized into an inactive etomidate acid, and after drug withdrawal, the wake-up quality is good; and the body's corticosteroid function can be rapidly recovered after a single administration or continuous administration.

Abstract: A recombinant human collagen-based multifunctional stent coating and a preparation method thereof are provided. The preparation method includes (1) activating a substrate material; (2) placing the activated substrate material in an amino compound-containing solution for a reaction to obtain an aminated substrate material; (3) placing the aminated substrate material in a polyanion electrolyte solution for a reaction, and cleaning with deionized water. The recombinant human collagen-based multifunctional stent coating prepared by the present invention effectively improves the anticoagulation and rapid endothelialization performance of biomaterials, such as vascular stent materials, and reduces the late thrombosis and restenosis problems existing in current stent materials.

Abstract: A method for preparing an organic boron fertilizer for engineering wound soil remediation includes a step of: effectively compounding at least one of chitin oligosaccharide, wormcast and silkworm excrement, at least one of water and hydrogen peroxide, an organic boron element solution, sodium alkyl benzene sulfonate and polysorbate under certain conditions. The present invention has significant effects on improving physical and chemical properties of engineering wound soil, enhancing availability of boron element in the soil, preventing plants from physiological diseases caused by lack of boron, and promoting growth and development of the plants.

Abstract: A method for preparing an organic complex microelement fertilizer for engineering wound soil remediation includes compounding chitosan oligosaccharide or/and earthworm dung or/and silkworm sand, water or/and hydrogen peroxide, an organic complex trace element solution, polyethylene glycol octyl phenyl ether, and polysorbate under certain conditions. The present invention can significantly improve physical and chemical properties of engineering wounds, enhance effectiveness of trace elements in soil, and prevent plant physiological diseases due to lack of trace elements, and promote plant growth and development.

Abstract: A viscoelastic surfactant (VES) for a self-diverting acid under high temperature has a structural formula shown as formula (I), wherein, n is saturated hydrocarbon with 2 to 8 carbon atoms; R1 is saturated or unsaturated hydrocarbon with 18 to 28 carbon atoms; R2 and R3 are independently methyl, ethyl or hydrogen, and R2 and R3 can be the same or different; and X? is any one of Cl?, Br?, CO32?, SO42?, HCOO? and CH3COO?. The method for preparing the surfactant includes subjecting a fatty acid and an organic amine to acid-amine condensation to obtain an intermediate. The intermediate reacts with a metal hydride to obtain a fatty amine. Then, an acid solution is used to protonate the fatty amine to obtain an ultra-long-chain viscoelastic cationic surfactant. The present invention also provides use of the surfactant as a thickener for a self-diverting acid.

Abstract: A method for positioning key features of a lens based on ocular B-mode ultrasound images includes: acquiring and preprocessing the ocular B-mode ultrasound images to obtain a preprocessed B-mode ultrasound image, eyeball coordinates and lens coordinates; sending the preprocessed B-mode ultrasound image, the eyeball coordinates and the lens coordinates into a trained target detection network YOLOv3 to obtain eyeball position images and lens position images; substituting the eyeball position images and the lens position images into a trained feature extraction network group to obtain image features and feature coordinates corresponding to the eyeball position images and the lens position images, respectively; substituting the image features into a trained collaborative learning network to screen key image features; and marking a feature coordinate corresponding to the key image features on the ocular B-mode ultrasound images to complete positioning the key features of the lens.

Abstract: A bioprosthetic valve and a preparation method thereof are provided. The bioprosthetic valve includes a stent and a functional biological tissue material attached to the stent. The functional biological tissue material is a biologicaltissue covalently bonded with an active group and a functional molecule or group. The method improves the anti-thrombosis and anti-calcification functions by covalently modifying the surface of a biological valve using an active group and a functional molecule or group with a substantial degree of grafting. The new bioprosthetic valve does not include aldehyde residues, exhibits excellent biocompatibility, optimal mechanical properties, high stability, and can meet the performance requirements of a biological valve delivered through a catheter.

Abstract: A two-quaternary ammonium compound has a structural formula of formula (I). L1 is a C1 to C8 alkylene group; L2 is a C1 to C8 alkylene group; Z1 is nitro group or a halogen or methoxy group; Z2 is nitro group or a halogen or methoxy group; Z3 is nitro group or a halogen or methoxy group; R?H or a C1 to C6 alkyl group; a, b, and c are independently an integer from 0-5; and M is a pharmaceutically acceptable anion, such as a bromine ion, chlorine ion, sulfonate radical, etc. A stereoisomer or mixture of stereoisomers, or a pharmaceutically acceptable salt or solvate or eutectic of the compound of formula (I) forms a composition with a pharmaceutically acceptable carrier, or forms a compounded prescription with other active components, and the composition or compounded prescription may be used in the preparation of a muscle relaxant.

Abstract: This disclosure relates to reactor control, and more particularly to a control rod drive mechanism and a reactor control system. The control rod drive mechanism includes a lifting-lowering assembly, a mounting assembly and a release assembly. The mounting assembly is configured to mount a control rod. The lifting-lowering assembly includes a fixing component, a scissor-type lifting-lowering mechanism and a lifting-lowering component. An end of the scissor-type lifting-lowering mechanism is connected to the fixing component, and the other end is connected to the lifting-lowering component. The scissor-type lifting-lowering mechanism is configured to drive the lifting-lowering component to move close to or away from the fixing component. The release assembly is movably arranged on the lifting-lowering component, and is detachably connected to the mounting assembly. The release assembly is configured to move relative to the lifting-lowering component when power is off to release the mounting assembly.

Abstract: A T-type DC circuit breaker includes a main branch, a first commutation switch, a second commutation switch, and a bypass branch. The first commutation switch and the second commutation switch are arranged at both ends of the main branch, respectively. The bypass branch is connected in parallel with the main branch. The main branch includes at least one half-controlled power electronic component. The bypass branch includes a bypass capacitor and a bypass diode connected in series. Each of the first commutation switch and the second commutation switch includes at least one fully-controlled power electronic component. The first commutation switch is connected in parallel with a first surge arrester, and the second commutation switch is connected in parallel with a second surge arrester. The grounded branch is arranged between the main branch and the second commutation switch and is grounded or connected to the negative terminal of the load.

Abstract: An anti-thrombotic and endothelialization-enhanced bioprosthetic valve material and preparation thereof are provided. The preparation method includes the following steps: immersing a glutaraldehyde cross-linked bioprosthetic valve material in functional reagent solution for 1-24 h, adjusting pH value of the solution to 3-8, removing it from solution and cleaning with deionized water. The new valve material of the present invention can effectively reduce the toxicity and side effects of the existing glutaraldehyde cross-linked bioprosthetic valve material and effectively reduce thrombosis, along with enhanced endothelialization. The material prepared can be used for pulmonary valve, aortic valve, mitral valve, tricuspid valve, venous valve and other cardiovascular implantable medical devices.

Abstract: A wireless passive probe solves problems such as the measurement accuracy of the field strength detecting device in the prior art is affected by the communication device and the system structure is complicated, which includes a probe for collecting data in the field to be measured; wherein the wireless passive probe further comprises: a wireless transmission module, an antenna module, sensors, and a microprocessor. The wireless passive probe of the present invention transmits position temperature, field strength, moisture, air pressure probe serial numbers and the coordinate signals of the probe in real time through the wireless transmission module, and provides the power supply to the communication module through detecting or receiving microwave signals through the antenna, thereby avoiding inaccurate wireless measurement of the probe field caused by the field to be tested which is not tightly sealed and the cable.