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Copyright of Railway Investigation & Surveying is the property of Railway Investigation & Surveying Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Vascular transplantation is a hot research topic in vascular surgery at present. However, the detection of mechanical properties of preserved vascular wall needs to be solved urgently. OBJECTIVE: To summarize the techniques used by researchers to study arterial wall mechanics and the problems faced in this research direction. METHODS: The first author searched CNKI, WanFang, PubMed, and Google Scholar databases for relevant literature published from 2016 to 2022. The Chinese search terms were “aortic blood vessel, arterial wall, mechanics, elasticity, detection method” and the English search terms were “aortic vessels, arterial walls, mechanical model, elastic structure, mechanical testing.” The relevant literature about the distribution of mechanical structure of aortic blood vessel walls and relevant detection methods were retrieved. Finally, 54 articles regarding mechanical and micromechanical testing were induced for review. RESULTS AND CONCLUSION: The arterial wall is characterized by complex microstructure, which affects the mechanical properties of vascular tissue. The main components include collagen and elastin fibers, proteoglycans, vascular smooth muscle cells, and matrix. These components are often damaged during cryopreservation. Among them, vascular smooth muscle cells play a key role in the active mechanical response of the arteries, and collagen and elastin determine the passive mechanical response. After the treatment of vascular grafts, the technologies of detecting vascular wall skeleton damage still need to be further explored or summarized to obtain a set of more accurate methods, so as to evaluate vascular wall skeleton damage in multiple dimensions and help in [ABSTRACT FROM AUTHOR]

Copyright of Wool Textile Journal is the property of National Wool Textile Science & Technology Information Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ridge culture can slow down the runoff of rain and prolong the infiltration time of rain, it plays a role on intercepting rain and protecting soil; furthermore, it could increase the cultivated area, thicken the soil layer which close to crop root system, make it easy to receive the illumination, improve the temperature of ground surface, benefit growth and promote the maturity of crops. The corn ridge culture no-till planter from Northeast China exists many problems so far, such as too large equipment quantity, destroying ridge shape while operating, serious compaction of soil, thicken the plow pan, caused deterioration of physiochemical properties of arable soil and fertility decline. In order to optimize the design soil work tool of no-till planter, the domestic and overseas development states of soil work tool testing device was analyzed, and combined with the situation of corn conservation tillage in Northeast China, the testing device of soil work tool was researched, designed and manufactured. The testing device could be applied to different farming methods, different ridge distances and variety of soil working tools. The testing device is a mounted device, which mainly composes of force measurement framework, four-bar profiling mechanism, pull pressure sensor, angular displacement sensor, linear displacement sensor and soil work tool fixture. There are two pull pressure sensors installed on and below the four-bar profiling mechanism, angular displacement sensor installed on the axis of rotation; soil work tool fixed to the force measurement framework with linear displacement sensor on it. It will detect the up and down displacement change of force measurement framework while testing (scilicet the change of the entering soil depth of work tool). Given the resultant force of upper and lower link and the gravity of testing device, the working resistance of soil work tool can be calculated. The resultant force of upper and lower link, gravity, and working resistance meet at one point, formed a balanced system of force. The data collecting card will collect testing data, which will be sent to computer in time. Computer software could record data accurately and display dynamic data waveforms. It can determine working resistance (size, orientation, focus) of the soil working tool, working depth and additional weight of machines by processing the data which obtained from test results, and provide reference for optimal design of soil working tool. Through test the working performance of Archimedes spiral disc cutting knife which is soil working tool, concluded that working resistance for breaking the corn stubble on the root is 1868.38 N, force direction angle is 67.66 degrees, stubble cutting depth is 7.52 cm, the distance between line of action and center of soil work tool is 4.59 cm, the total weight of devices and additional weight should be greater than 175.79 kg. On this basis, through analyze the time-dependent graphs of disc cutting knife working resistance, which include horizontal component of force that against the advancing direction of test device and vertical component of force that perpendicular to ground, obtained a mechanism that image of cutting time and cutting resistance when disc cutting knife cutting corn stubble, which laid a foundation and experimental verification for load specific property of no-tillage planter. [ABSTRACT FROM AUTHOR]