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Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering 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.)

In the present, the mechanized harvest technology of garlic in China is still in infancy. Most of the current domestic garlic harvesters only can accomplish the processes of digging and laying. However, the garlic combine harvester, which can synchronously finish the processes of digging, cleaning soil, cutting stem, cutting beard, gathering garlic bulb, etc., is still under test and demonstration. Furthermore, picking is the most important and difficult process of combine harvest, because the bad separation will result in another manual cutting. Different with the harvest mode of the developed countries, the farmers in China pull out the young garlic shoot in its early stage, which causes the garlic to collapse and affects its locating in the application of half feeding combine harvest. Besides, the residual stem is long, the damage rate is high and the cut pass rate is low. In view of the above problems, a picking device of garlic combine harvester was designed, realizing the garlic plant flexibly clamped, the garlic being sorted one by one and aligned automatically. In order to further study the garlic picking device, the garlic picking testbed was designed. The garlic picking testbed consists of a garlic picking device, shelf and transmission system. The main goal of testbed is the garlic picking device which consists of a clamping device, a rank-alignment device, a cutting device. In order to enhance operational performance of garlic picking device, reduce the residual stem length, the damage rate and increase cutting surface pass rate, the Box-Benhnken central composite experimental design principle was conducted in this paper. A four factors and three levels response surface experiment was completed on the garlic picking testbed, with four factors which affect picking quality. This paper established the response surface model and studied the factors affecting picking quality. At the same time, it synthetically optimized the factors affecting picking quality. The results showed that trial factors had great effects on picking quality. The significant effects of clamp number, main chain speed, clamp height, and clamp angle on residual stem length were in a decreasing order; The significant effects of main chain speed, clamp number, clamp height, and clamp angle on damage rate were in a decreasing order; The significant effects of main chain speed, clamp number, clamp height, and clamp angle on cut pass rate were in a decreasing order. The higher main chain speed, higher clamp height, more numbers of plants, then the residual stem length was longer, in contrast, the residual stem length was shorter. The higher main chain speed, shorter clamp height, more numbers of plants, then the damage rate was higher, in contrast, the damage rate was lower. The lower main chain speed, higher clamp height, less numbers of plants, then the cut pass rate was higher, in contrast, the cut pass rate was lower. The interaction of various factors affecting residual stem length, damage rate and cut pass rate were not significant changed. The optimum parameters were that the speed of main clamping chain was 1.05 m/s, the clamping angle was 77°, the clamping height was 220 mm, and the clamping number was two. The results have provided a base for the garlic picking mechanism. [ABSTRACT FROM AUTHOR]

Abstract: In this work, hierarchically porous TiO2–B nanoflowers have been successfully synthesized via a facile solvothermal method followed by calcination treatment. The TiO2–B nanoflowers are constructed by thin nanosheets, presenting ultrahigh specific surface area, up to 214.6m2 g−1. As anode materials for Li-ion batteries, the TiO2–B sample shows high reversible capacity, excellent cycling performance and superior rate capability. The specific capacity of TiO2–B could remain over 285mAhg−1 at 1C and 181mAhg−1 at 10C rate after 100 cycles. We believe that the pseudocapacitive mechanism, ultrahigh surface area and scrupulous nanoarchitecture of the TiO2–B are responsible for the enhancement of electrochemical properties. [Copyright &y& Elsevier]

Amonton's law of friction states that the friction force is proportional to the normal force in magnitude, and the slope gives a constant friction coefficient. In this work, with molecular dynamics simulation, we study how the kinetic friction at the nanoscale deviates qualitatively from the relation. Our simulation demonstrates that the friction behavior between a nanoscale AFM tip and an elastic graphene surface is regulated by the coupling of the applied normal force and the substrate deformability. First, it is found that the normal load-induced substrate deformation could lower friction at low load while increasing it at high load. In addition, when the applied force exceeds a certain threshold another abrupt change in friction behavior is observed, i.e. , the stick-slip friction changes to the paired stick-slip friction. The unexpected change in friction behavior is then ascribed to the change of the microscopic contact states between the two surfaces: the increase in normal force and the substrate deformability together lead to a change in the energy landscape experienced by the tip. Finally, the Prandtl-Tomlinson model also validates that the change in friction behavior can be interpreted in terms of the energy landscape., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)