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Objective: To improve the separation efficiency of constricted clam shell and meat. Methods: Taking Lianyungang double-headed razor as the test object, taking frequency, amplitude, and sieve surface inclination as the test factors, and taking the screening efficiency and the ratio of the shell in the meat as the main control targets, a single-factor test was carried out, and the test results were analyzed by Design-Expert software. An analysis of variance was performed to establish a regression model matching the frequency, amplitude, and inclination of the screen surface to the screening efficiency and the ratio of husks in the meat. Using the response surface optimization analysis method, the optimal matching of working parameters for the separation and screening device of constricted razor shell and meat was obtained. Results: When the discharge rate was controlled at 1.2 kg/s, the shell opening rate was controlled at 97%, the frequency was set at 21.6 Hz, the amplitude was set at 3.6 mm, and the screen inclination angle was set at 9°, the screening efficiency of constricted razor was improved, with the screen efficiency of 97.60%, and the shell-on ratio of the meat of 4.52%. Conclusion: The designed vibrating screening device for constricted razor has high screening efficiency and good adaptability, which can meet the preliminary processing requirements.

π-Stacking is common in materials, but different π–π stacking modes remarkably affect the properties and performances of materials. In particular, weak interactions, π-stacking and hydrogen bonding often have a significant impact on the stability and sensitivity of high-energetic compounds. A fused [5,7,5]-tricyclic energetic compound with a conjugated structure has been designed and synthesized. 4 H -[1,2,5]Oxadiazolo[3,4- e ][1,2,4]triazolo[3,4- g ][1,2,4]triazepin-8-amine is obtained in 48% yield from 3-amino-4-carboxy-1,2,5-oxadiazole through an efficient two-step reaction. Owing to its layered planar structure and weak π interactions between layers, 4 H -[1,2,5]oxadiazolo[3,4- e ][1,2,4]triazolo[3,4- g ][1,2,4]triazepin-8-amine exhibits high thermal stability (Td = 318 °C), low sensitivity (IS = 40 J, FS = 360 N), and relatively excellent detonation performance (D = 7059 ms–1 , P = 20.2 GPa). This detonation performance is superior to that of the conventional explosive TNT. The developed procedure provides a new method for the synthesis of fused ring compounds. [ABSTRACT FROM AUTHOR]

As the largest blockchain platform supporting smart contracts,millions of smart contracts have been deployed on Ethereum.Since the deployed smart contracts cannot be modified even if the contracts contain bugs,it is critical for developers to eliminate bugs prior to the deployment.Many smart contract analysis tools have been proposed.These tools either use bytecode-based symbolic execution to detect bugs,or convert the source code to an intermediate representation and then detect bugs.The tools based on symbolic execution usually cannot cover many types of bugs in source code.Converting the source code to an intermediate representation negatively impacts the detection speed.Moreover,these tools are bug detectors,which cannot automatically fix bugs based on analysis results.To address these limitations,we propose an approach named SolidityCheck,which employs regular expressions,program instrumentation and statement replacement in source code to quickly detect bugs and fix certain types of bugs.We conduct extensive experiments to evaluate SolidityCheck.The experimental results show that,compared with existing approaches,SolidityCheck demonstrates excellent performances on multiple indicators.

In developing tissues, cell polarization and proliferation are regulated by morphogens and signaling pathways. Cells throughout the Drosophila wing primordium typically show subcellular localization of the unconventional myosin Dachs on the distal side of cells (nearest the center of the disc). Dachs localization depends on the spatial distribution of bonds between the protocadherins Fat (Ft) and Dachsous (Ds), which form heterodimers between adjacent cells; and the Golgi kinase Four-jointed (Fj), which affects the binding affinities of Ft and Ds. The Fj concentration forms a linear gradient while the Ds concentration is roughly uniform throughout most of the wing pouch with a steep transition region that propagates from the center to the edge of the pouch during the third larval instar. Although the Fj gradient is an important cue for polarization, it is unclear how the polarization is affected by cell division and the expanding Ds transition region, both of which can alter the distribution of Ft-Ds heterodimers around the cell periphery. We have developed a computational model to address these questions. In our model, the binding affinity of Ft and Ds depends on phosphorylation by Fj. We assume that the asymmetry of the Ft-Ds bond distribution around the cell periphery defines the polarization, with greater asymmetry promoting cell proliferation. Our model predicts that this asymmetry is greatest in the radially-expanding transition region that leaves polarized cells in its wake. These cells naturally retain their bond distribution asymmetry after division by rapidly replenishing Ft-Ds bonds at new cell-cell interfaces. Thus we predict that the distal localization of Dachs in cells throughout the pouch requires the movement of the Ds transition region and the simple presence, rather than any specific spatial pattern, of Fj.

Based on the development trends, graphitized carbon steel has been proposed as a low-sulfur and Pb-free free-cutting steel. This steel has attracted considerable attention because of its excellent cutting performance and good cold forging performance.This study investigates graphitized carbon steel containing 0. 46% C with ferrite and graphite. In particular, its compression deformation at room temperature was studied using a universal testing machine. The load-displacement curve was fitted, the drum shape and radial elongation of the end face of the compression specimens were calculated, the surface quality and microstructure of the compression specimens were observed using optical microscopy and field-emission scanning electron microscopy, and the micro-deformation of graphite particles and the ferritic matrix in the compression specimens was statistically analyzed using Image-Pro 6. 0. The results show that the tested steel exhibits good compression deformation performance. According to the varying characteristics of the load with respect to displacement, the compression deformation process of the tested steel is divided into two stages with a displacement of 7 mm (corresponding to 58. 3% reduction) : at the compression stage with displacement ≤7. 0 mm, the load increases linearly with displacement.The value of the drum shape increases with increasing displacement, reaching a maximum value of 14. 6%, the radial elongation of the end face of the compression sample increases 34%, and the Vickers hardness at the center of the compression sample reaches its maximum value of 38. 1 HV. At the compression stage with displacement > 7. 0 mm, the load increases exponentially, the value of the drum shape gradually decreases from its maximum value, the radial elongation of the end face of compression sample increases by 83. 1%compared with that at 7. 0 mm displacement, and the Vickers hardness at the center of the compression sample reaches its minimum value of 32. 7 HV. The aforementioned experimental data show that, in the compression process with displacement ≤7. 0 mm, the three non-uniform deformation zones within the compression sample are consistent with the traditional compression model; however, in the compression process with displacement > 7. 0 mm, the center of the sample is no longer the deformation zone with the largest deformation degree in the traditional compression model. That is, the deformation degree of the three nonuniform deformation zones changes at this stage. This change leads to sharp increase in the load and to a decrease in the drum shape. In addition, during the compression deformation process, the micro-deformation degree of the graphite particles is greater than that of the ferritic matrix in the three inhomogeneous deformation zones. This is attributed to the crystal structure of graphite. In particular, graphite has a layered, planar structure in which bonding between layers occurs via weak van der Waals interactions, which enables layers of graphite to be easily separated or to slide past each other.