Abstract: A seawater corrosion-resistant marine engineering steel and a preparation method thereof are provided. The seawater corrosion-resistant marine engineering steel consists of the following chemical compositions in percentage by mass: C: 0.011-0.069%, Si: 0.11-0.29%, Cr: 1.51-1.99%, Nb: 0.02-0.05%, Zr: 0.01-0.02%, RE: 0.0034-0.02%, and the balance of Fe and inevitable impurities. The mass percentages of Zr element and RE element also satisfy the following formulas: 0.01%<Zr+RE<0.02%, and Zr/RE=1-3. The marine engineering steel is designed with cheap chemical compositions of low carbon, low silicon and medium chromium, and is completely free of valuable corrosion-resistant metal elements such as Ni and Cu. Instead of the traditional Al deoxidization technology, Si deoxidization assisted by Zr?RE composite deoxidization is used to form a fine, dispersed and uniform composite oxysulfide.

Abstract: A high-strength steel with excellent neutral aqueous medium corrosion resistance, and a preparation method and application thereof are provided. A steel plate is designed with cheap chemical compositions of low carbon, low silicon and medium manganese, and is completely free of precious metal elements such as Cr, Ni and Cu, thereby greatly reducing the material cost. According to the present invention, instead of the traditional Al deoxidation technology, Si or Si—Mn deoxidation assisted by Zr—Ti composite deoxidation is used to form a fine, dispersed and uniform composite oxysulfide, which greatly decreases the density of corrosion-active inclusions, and obviously improves the neutral aqueous medium corrosion resistance. Through the design of low carbon equivalent, the steel plate has excellent welding performance; and the composite microalloying of Nb, Zr and Ti is adopted to cooperate with the TMCP rolling parameter control, so that the steel plate has high strength and good extensibility.

Abstract: A composite additive for forming inclusions with a core-shell structure, a preparation method and a smelting method are provided. The composite additive includes the following chemical components by mass percentage: Fe: 41-59%, Zr: 5-11%, Ti: 14-26%, Mg: 11-19%, and RE: 4-10%, in which the mass percentage content of Zr element, Ti element, Mg element and RE element satisfies a formula: (Ti+Mg+RE)/Zr=4-8. The composite additive for forming inclusions with a core-shell structure has the characteristics of fineness, spheroidization and obvious dispersion effect. This type of inclusions has a bulk modulus similar to that of the iron matrix, which can significantly improve the plasticity, toughness, fatigue resistance, local corrosion resistance, welding performance, cold bending performance, etc. of steel materials, suitable for steel types with strict requirements on the shape of inclusions, such as marine steel, pipeline steel, container steel, cold heading steel, tool and die steel, etc.

Abstract: A Ni-free micro-alloyed high-strength steel with ultra-low temperature toughness and a preparation method thereof are provided. The micro-alloyed high-strength steel includes the following chemical components by mass percentage: 0.011% to 0.099% of C, 0.051% to 0.24% of Si, 1.21% to 1.49% of Mn, 0.030% to 0.059% of Nb, 0.009% to 0.016% of Ti, 0.001% to 0.018% of Zr, 0.001% to 0.018% of rare earth (RE), and the balance of Fe and inevitable impurities. The mass percentage also meet the following formulas: 0.21%<C+Si<0.24%, and Si/C=1 to 8; 0.02%<Nb+Ti<0.05%, and Nb/Ti=1 to 3; 0.010%<Zr+RE<0.019%, and Zr/RE=1 to 6. The micro-alloyed high-strength steel uses a completely different composition design (i.e., a simple low-cost Ni-free composition design) to realize ultra-low temperature toughness, and with the help of Zr+RE compound deoxidation and Nb+Ti compound micro-alloying technologies, realizes ultra-low temperature toughness at ?100° C. to ?120° C.

Abstract: A Nb-element micro-alloyed bulk multi-component alloy with high-temperature resistance and wear resistance, a preparation method therefor, and applications thereof are provided. The alloy includes chemical components at corresponding contents: 2.10-2.24 wt % of Al, 20.70-20.86 wt % of Cr, 35.20-35.54 wt % of Ni, 19.10-19.46 wt % of Ti, 0.70-0.85 wt % of Nb, and the balance of Fe and unavoidable impurities, and the chemical components need to simultaneously meet relations: (1) 24.76?Fe/Nb?31.72; (2) 6.81?Fe/(Nb+Al)?7.93; (3) 1.04?Fe/(Nb+Ti)?1.13. Wear resistance of the alloy is 4-5 times higher than that of a traditional wear-resistant material NM500 in terms of the same hardness. After two-step tempering heat treatment under the same parameters, the NM500 is reduced in hardness by 58.64-68.93% with respect to its quenched and tempered condition, and the hardness of material of this invention is reduced by 31.75-37.74% with respect to its as-cast condition.

Abstract: A La-element micro-alloyed AlCrFeNiTi bulk alloy with high corrosion resistance and wear resistance and a preparation method therefor and applications thereof are provided. The alloy includes the following chemical components in corresponding percentages: 2.05 wt % to 2.15 wt % of Al, 20.50 wt % to 20.65 wt % of Cr, 34.50 wt % to 35.54 wt % of Ni, 18.80 wt % to 19.16 wt % of Ti, 1.05 wt % to 1.15 wt % of La, and the balance of Fe and inevitable impurities, wherein the chemical components need to meet the following three relations at the same time: (1) 18.57?Fe/La?22.00; (2) 6.47?Fe/(La+Al)?7.45; and (3) 1.05?Fe/(La+Ti)?1.16. Compared with AISI 310S stainless steel, the alloy is improved by 280% to 290% in hardness, reduced by 4% to 7% in friction coefficient, and reduced by 17% to 34% in wear amount, increased by 73% to 77% in self-corrosion potential, and decreased by 96% in corrosion current density on average.

Abstract: A titanium-containing calcium hexaaluminate material and preparation method thereof is disclosed. The technical solution is: using 60˜80 wt % alumina micro powder, 5˜20 wt % calcium-containing micro powder, 10˜20 wt % titania micro powder and 1˜10 wt % manganese oxide micro powder as raw materials, blending the raw materials evenly in a planetary ball mill to obtain a blend, machine pressing the blend at 100˜200 MPa to obtain a green body, drying the green body at 110˜200° C. for 12˜36 h, and incubating the dried green body at 1500˜1800° C. for 1˜8 h to obtain the titanium-containing calcium hexaaluminate material. The present disclosure has low cost and simple process, and the prepared titanium-containing calcium hexaaluminate material has the characteristics of good chemical stability, high thermal shock resistance and strong melt resistance to titanium-aluminum alloy.

Abstract: The disclosure provides a method for determining a slope slip plane with a gently-inclined soft interlayer, including: S1, determining a curve formed with a slip arc of a trailing edge tearing plane, a soft interlayer plane and a slip arc of a leading edge shear opening as a slope slip plane; S2, calculating a slip plane stability coefficient; S3, determination of a position of the gently-inclined soft interlayer plane: if the slip plane stability coefficient is less than 1 but close to 1, determining that the position of the slope slip plane is accurate; otherwise, moving the position of the soft interlayer plane and repeating steps S1 and S2, until the slip plane stability coefficient is less than 1 and close to 1. The method is simple, and has a high accuracy for determining a non-circular slip plane with a soft interlayer as a bottom slip plane.

Abstract: The present disclosure relates to a magnesium-based raw material and a preparation method thereof. According to the technical solution, 40-60 wt % fused magnesia particles, 30-40 wt % fine monoclinic zirconia powder, 5-20 wt % fine zirconium oxychloride powder, 0.5-1.5 wt % calcium hydroxide nanopowder, 0.2-0.5 wt % calcium hydroxide nanopowder, and 0.1-0.3 wt % maleic acid are stirred for 15 min to mix well in a high-speed mixing mill at a constant temperature of 25° C. to obtain a mixed powder; and the mixed powder is mixed through a ball mill at a constant temperature of 25° C. for 3 min, roasted in a high temperature furnace at 250-400° C. for 0.5-3 h, and finally cooled to room temperature.

Abstract: The present invention provides a microalloyed steel mechanical property prediction method based on globally additive model, including the following steps: determining some influencing factors of the microalloyed steel mechanical property prediction model; calculating the components and contents of carbonitride precipitation in a microalloyed steel rolling process; expressing the microalloyed steel mechanical property prediction model as an additive form of several submodels according to generalized additive model; estimating the microalloyed steel mechanical property prediction model; and verifying reliability of the submodels. The microalloyed steel property prediction models obtained in the foregoing solution have advantages such as high prediction precision and a wide adaptation range, and may be used for design of new products and steel grade component optimization, so as to reduce the quantity of physical tests, shorten the product research and development cycle, and reduce costs.

Abstract: A shear box of shear rheology experiment of a soft rock for simulating the coupling of the rainfall seepage and blasting vibration includes an upper shear box, a lower shear box, a normally-loading indenter, a normally-loading cushion block and a test piece joint. The upper shear box is tightly connected to the lower shear box by a vertical roll. The vertical roll passes through the through holes at both sides of the upper shear box and is engaged with the lower shear box through female thread connection holes. The normally-loading indenter passes through a circular through hole and presses against the normally-loading cushion block. The first end of the test piece joint is installed into a water or gas outlet hole, and the second end of the test piece joint is directly mortised into a rock test piece.

Abstract: The invention provides a method for purifying silicon by means of a phase separation dealloying reaction, including: mixing a silicon raw material containing metallic or non-metallic impurities with magnesium powder first and then fully reacting under an inert atmosphere so as to obtain a first product; placing the first product in a nitrogen-containing atmosphere to undergo a nitriding reaction to form three-dimensional porous silicon and magnesium nitride distributed in pore channels thereof so as to obtain a second product, the impurities further being separated during the precipitation and crystallization of silicon, and being dissolved in the liquid-phase magnesium nitride; treating the second product by using acid-pickling, the magnesium nitride and impurities being dissolved and converted into a solution, and a solid product being high-purity porous silicon.

Abstract: The present disclosure relates to a magnesium-based raw material with low thermal conductivity and low thermal expansion and a preparation method thereof. According to the technical solution, 40-60 wt % fused magnesia particles, 30-40 wt % fine monoclinic zirconia powder, 5-20 wt % fine zirconium oxychloride powder, 0.5-1.5 wt % calcium hydroxide nanopowder, 0.2-0.5 wt % calcium hydroxide nanopowder, and 0.1-0.3 wt % maleic acid are stirred for 15 min to mix well in a high-speed mixing mill at a constant temperature of 25° C. to obtain a mixed powder; and the mixed powder is mixed through a ball mill at a constant temperature of 25° C. for 3 min, roasted in a high temperature furnace at 250-400° C. for 0.5-3 h, and finally cooled to room temperature. The magnesium-based refractory material prepared has the advantages of relatively low thermal conductivity, low thermal expansion coefficient, excellent dispersibility, and strong resistance to slag penetration and erosion.

Abstract: A preparation method of an ant nest like porous silicon for a lithium-ion battery comprises: (1) enabling a magnesium silicide raw material to react for 2-24 h in an ammonia gas or an atmosphere containing an ammonia gas at 600-900° C. to obtain a crude product containing porous silicon; and (2) subjecting the crude product containing porous silicon to an acid pickling treatment to obtain the ant nest like porous silicon. The preparation method has the advantages of simplicity and easiness. A large amount of porous silicon can be obtained by directly heating the magnesium silicide raw material in the ammonia gas or a mixed gas of the ammonia gas and an inert gas with a high yield.

Abstract: A multi-police-officer collaborative round-up task allocation and path planning method under the constraint of a road network, including: acquiring a road topological map G of the road network; acquiring police officer distribution information and information of a task target location in the G of the road network; according to the position where the task target appears, a set of nodes that the task target is next likely to reach are determined; acquiring the movement speed of police officers and the task target; confirming a set of police officers to be assigned according to an interception point set and the movement speed of the police officers and the task target; calculating the congestion degree of each intersection in the interception point set; building a multi-police-officer collaborative round-up task allocation and path planning optimization model; solving the optimization model to obtain a multi-police-officer collaborative round-up task allocation and path planning scheme.

Abstract: A rotary joint, including: a hydraulic follow-up mechanism and a rotary transmission mechanism. The hydraulic follow-up mechanism includes a cylinder body, a valve sleeve, a valve core, a valve body, a left end cover and a right end cover. The rotary transmission mechanism includes a tray, a stabilizing ring, a follow-up disk, a torque transfer disk and a stable supporting wheel mechanism. The left end cover and the right end cover are arranged at the left and right ends of the cylinder body, respectively. The valve body is concentrically mounted in a cylindrical hollow chamber of the cylinder body. The output shaft at the right end of the valve body projects out of the right end cover. The right end of the valve core is provided with a valve core torque transfer shaft extending rightwards through the right end of the valve body.

Abstract: A system and method for controlling a porous medium burner of medium-high temperature heating field, the control system includes a local control system and a remote control system; the local control system is configured for acquisition and feedback of data, and execution of an action; and the remote control system communicates with the local control system in real time and is configured for storage and analysis of data and transmission of an instruction. A system and method for controlling a porous medium burner of medium-high temperature heating field, which can effectively perform prediction and prevention of flashback, be adapted to combustion of gases with different calorific values, monitor and diagnose, in real time, a usage status of a porous medium material, and be suitable for the functions such as real-time monitoring of preheating of air and a fuel gas.

Abstract: Provided is a classification optimization method for steel grade family of a steel rolling model, including: step 1: calculating the deformation rate and deformation resistance of a rolled piece according to rolling process data; step 2: reversing the “equivalently measured” deformation resistance according to the measured roll force; step 3: drawing a scatter plot of data on a graph, and judging whether layer division is reasonable according to distribution characteristics; and step 4: for the unreasonable division of steel grade family, optimizing the existing classification of steel grade family using a new algorithm called line clustering, determining steel grade codes that need to be divided into new family, searching for the shortest distance from a sample point to the curve of each cluster centre based on a Nelder-Mead algorithm, dividing all data points into k subsets according to the principle of proximity, fitting a power curve to each data subset using a least square method, repeating the above ste

Abstract: The multi-tube parallel free rotary thread demisting device includes a soot pit, a side liquid guide plate, liquid accumulation units, free rotary thread units, a fixing support, a flue gas inlet, motor connecting shafts, motors, a casing, a flue gas outlet, and a base support. A main body of the device includes a plurality of free rotary thread units and a plurality of liquid accumulation units that are mounted in parallel. The motors are mounted on an outer wall of the casing. The free rotary thread units are connected to the motors via the motor connecting shafts respectively. The motor connecting shafts are fixed via the fixing support. The device has low resistance, high efficiency, and high flue gas treatment throughput, and can avoid scaling and jamming.

Abstract: Provided is a classification optimization method for steel grade family of a steel rolling model, including: step 1: calculating the deformation rate and deformation resistance of a rolled piece according to rolling process data; step 2: reversing the “equivalently measured” deformation resistance according to the measured roll force; step 3: drawing a scatter plot of data on a graph, and judging whether layer division is reasonable according to distribution characteristics; and step 4: for the unreasonable division of steel grade family, optimizing the existing classification of steel grade family using a new algorithm called line clustering, determining steel grade codes that need to be divided into new family, searching for the shortest distance from a sample point to the curve of each cluster centre based on a Nelder-Mead algorithm, dividing all data points into k subsets according to the principle of proximity, fitting a power curve to each data subset using a least square method, repeating the above ste