Chinese Academy of Sciences

Dalian University of Technology

Other

Xiaodong Wang

Tao Zhang

Mingyuan Zheng

Aiqin Wang

Siying Ling

Jingguang Chen

Na Ji

Liding Wang

Ming Ling

Jifeng Pang

Huiyang Zhang

Yuying Shu

Yilei Chen

Hui Xing Wang

Yu Jiang

Xingyuan Wang

Weizhen Li

Kun Wang

Zhijun Tai

Yue Wang

Shuo Al

Zhifeng Lou

Likun Zhou

Aigin Wang

Ruiyan Sun

Xunlian Wang

Baodi Yu

A reference-level gear helix artifact for transferring gear helix value. The invention provides a reference-level gear helix artifact with a global symmetrical structure that can be easily obtained by generating method. The centroid point of the artifact passes through the geometric center of the artifact mandrel. The cylinder of the reference-level gear helix artifact is provided with the straight tooth groove, the left-hand tooth groove and the right-hand tooth groove, axial reference torus and radial reference cylinder, fine tooth threads and center holes. Among them, the straight tooth groove includes a pair of involute cylindrical surfaces with opposite 0&#xb0; helix angle, the left-handed tooth groove includes a involute helicoidal surface with 15&#xb0; and a involute helicoidal surface with 30&#xb0;, and the right-hand tooth groove includes a involute helicoidal surface with 15&#xb0; and a involute helicoidal surface with 30&#xb0;.

Reference-level gear helix artifact

A mutual-lapping device and mutual-lapping method for improving processing precision based on the principle of error averaging is proposed. The device including driving friction wheel, driving belt pulley, transmission belt A, connecting rod A, rotation shaft segment A, multi-ball sleeve, mutual-lapping gear A, tension spring, driven friction wheel, pendulum bar of the driven friction wheel, driven belt pulley, transmission belt B, connecting rod B, pressure spring of tensioning pulley, tensioner mechanism, rotation shaft segment B and mutual-lapping gear B. By mutual lapping the high-precision gears, not only the pitch deviation, tooth profile deviation, helix deviation and runout can be reduced synchronously, but also the machining cost is low. Meanwhile, the effect of improving pitch accuracy, profile accuracy, helix accuracy and runout accuracy and reducing surface roughness is remarkable.

Mutual-lapping device for improving gear machining accuracy and the mutual-lapping method thereof

An ultrasonic testing device and method for the connection force of interference fit. The motion control module can realize accurate positioning for the interference fit part and accurate control for motion in the circumferential direction and the axial direction; scanning increments of the circumferential direction and the axial direction are set, and the motion control module drives the interference fit part to perform circumferential and axial point scanning until the testing of the whole matching surface is completed. The ultrasonic signal measured by the point focusing water immersion probe is transmitted to a PC through a control loop in the testing process. Then the stress distribution of the matching surface is obtained through the relationship between the ultrasonic signal and contact stress Finally, the size of the connection force is calculated according to the static friction coefficient.

Ultrasonic testing device and method for connection force of interference fit

This invention provides a method for catalytic conversion of carbohydrates to low-carbon diols using alloy catalysts. In the process, carbohydrates as the feedstock are subjected to one-step catalytic conversion to realize the highly efficient and selective production of ethylene glycol etc. under hydrothermal conditions, with an alloy catalyst composed of tin, and a transition metal such as iron, cobalt, nickel, rhodium, ruthenium, palladium, iridium, platinum and copper, or a mixture thereof. The reaction is carried out in water at a temperature range of 120-300&#xb0; C., with a hydrogen pressure range of 1-13 MPa. Compared with the present petroleum based synthesis technology of ethylene glycol, the method in this invention possesses advantages of using renewable feedstock, high atom economy and environmental friendly. Besides, compared with other technologies using biomass as feedstock to produce ethylene glycol, the alloy catalyst in this invention possesses the advantages of few leaching amount, good hydrothermal stability and easy to recycle.

Method of catalytic conversion of carbohydrates to low-carbon diols by using alloy catalysts

The precision lapping and polishing device for external cylindrical surface of disk part and its taper error adjustment method. The device composes a circular baseplate, slant rails, baffles, pressure plates, copper blocks, a washer blanket; blanket plates, a set of bead shafting, a friction driving wheel, a DC motor, a mobile power supply, a LED lamp and a cover body. By adopting the working principle that the generatrix rotates around the fixed axis to form the cylindrical surface, the ultra-precision machining of the cylindrical surface of disk part is realized. The radial-continuous-automatic-micro feeding of the disk part is realized by thinning the thickness of the circular baseplate which is internally tangent to the generatrix of the circular baseplate during the process of lapping and polishing. The device has the advantages of operating simply, adjusting conveniently, low cost and is of important value for popularization and application.

Precision lapping and polishing device for external cylindrical surface of the disk part and its taper error adjustment method thereof

This invention discloses an approach for the separation of the close-boiling mixture of polyols. The raw material is ethylene glycol containing miscellaneous polyols (such as 1,2-propylene glycol and 1,2-butanediol). Over an acid catalyst, these miscellaneous polyols, through (1) a dehydration reaction, (2) pinacol rearrangement, and (3) acetalization or ketalization reaction, are converted into aldehydes (small amounts), acetals, and ketals (trace amount), which are simultaneously and readily separated via distillation. Meanwhile, after the reaction, the mixture is further separated to obtain an ethylene glycol product at a high purity. The invention provides a technique to remove the miscellaneous polyols from ethylene glycol via liquid-phase dehydration reactions under mild conditions, with low energy consumption. In particular, this approach is markedly effective for the removal of 1,2-butanediol that is difficult to be removed via conventional techniques. The purity of the resulting ethylene glycol product is high, and value-added acetals or ketals are co-produced.

Method for separation of close-boiling mixture of polyols

Tungsten carbide catalysts are used in preparation of ethylene glycol by hydrogenating degradation of cellulose. The catalyst includes tungsten carbide as main catalytic active component, added with small amount of one or more transition metals such as nickel, cobalt, iron, ruthenium, rhodium, palladium, osmium, iridium, platinum, and copper as the second metal, supported on one or more porous complex supports such as active carbon, alumina, silica, titanium dioxide, silicon carbide, zirconium oxide, for conversion of cellulose to ethylene glycol. The catalyst realizes high efficiency, high selectivity, and high yield in the conversion of cellulose to ethylene glycol at the temperature of 120-300&#xb0; C., hydrogen pressure of 1-10 MPa, and hydrothermal conditions. Compared to the existing industrial synthetic method of ethylene glycol using ethylene as feedstock, the invention has the advantages of using renewable raw material resources, environment friendly process, and excellent atom economy.

Methods of using tungsten carbide catalysts in preparation of ethylene glycol

A method for producing ethylene glycol, including (a) adding a polyhydroxy compound and water to a sealed high-pressure reactor, (b) removing air and introducing hydrogen, and (c) allowing the polyhydroxy compound to react in the presence of a catalyst while stiffing. The catalyst includes a first active ingredient and a second active ingredient. The first active ingredient includes a transition metal of Group 8, 9, or 10 selected from iron, cobalt, nickel, ruthenium, rhodium, palladium, iridium, and platinum, and/or a mixture thereof. The second active ingredient includes a metallic state of molybdenum and/or tungsten, or a carbide, nitride, or phosphide thereof. The method is carried out at a hydrogen pressure of 1-12 MPa, at a temperature of 120-300&#xb0; C. for not less than 5 min in a one-step catalytic reaction. The efficiency, selectivity, and the yield of ethylene glycol are high. The preparation process is simple and the materials used are renewable.

Method for producing ethylene glycol from polyhydroxy compound

A method for preparing ethylene glycol from cellulose uses the cellulose as the feed for the reaction. The cellulose conversion is performed over catalysts which are composed of the metallic state, carbides, nitrides, or phosiphides of molybdenum or tungsten, and metallic cobalt, nickel, ruthenium, rhodium, palladium, iridium, and platinum of the group 8, 9, or 10 transition metals. The catalytic conversion of cellulose is conducted at 120 to 300&#xb0; C. and hydrogen pressure 1 to 12 MPa under the hydrothermal conditions to achieve the high efficiency, high selectivity, and high yield of ethylene glycol. Compared to the existing method of preparing ethylene glycol from ethylene, the method, using the renewable raw material for the reaction, is friendly to the environment, and has high atom economy.

Method of preparing ethylene glycol from cellulose

Growing community of inventors

Liaoning, China

Xiaodong Wang