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In our research described here, a strong acid oxidizing agent was selected to modify the surface of carbon black (CB) to obtain oxidized carbon black (OCB) particles. These OCB particles were then subjected to an ionic bonding reaction with alkaline amine groups present on the surface of octadecylamine polyoxyethylene ether (AC1830) in the form of a paste, resulting in the production of polyether amine-modified oxidized carbon black particles (A-CB). FTIR confirmed the successful production of the A-CB particles. The PVA composite films were prepared using the casting method with varying amounts of A-CB as filler and PVA as the matrix. The films were then analyzed using tensile, scanning electron microscopy, dynamic thermo-mechanical analysis, DSC, and water absorption testing. The results showed that the tensile strength was highest at 3% A-CB, reaching 154.85 MPa. A-CB was well dispersed in PVA at low contents (1% and 3%). The loss modulus, energy storage modulus, crystallinity, and crystallization rate of the A-CB/PVA films improved compared to PVA films. Additionally, the issue of excessive water absorption in A-CB/PVA has been improved. [ABSTRACT FROM AUTHOR]

At present, in most coal mines, the coal pillar width of goaf-side roadway driving is determined by the average mining thickness. However, the thickness of the same coal seam could be varied greatly by various factors during the formation process. The large variation of mining thickness in the fully mechanized working face leads to large difference of surrounding rock deformation and complex damage mechanism of the goaf-side roadway driving. In order to solve the above problems, FLAC3D software is used to establish a roadway model so as to analyze the surrounding rock deformation and damage law under the average mining thickness, and determine the reasonable coal pillar width. When the average mining thickness is 18 m, on the side of the solid coal, the peak supporting pressure in the coal is positively correlated with the coal pillar width. Moreover, when the coal pillar width is greater than 8 m, the growth rate of the supporting pressure slows down. Therefore, the reasonable coal pillar width should be 8 m. This paper studies the influence of mining thickness on the stability of the surrounding rock of goaf-side roadway driving in the context of determined coal pillar width. The results show that when the coal pillar width is 8 m, with the increase of mining thickness, the shear damage area of roof increases, and the rock deformation range and the roof subsidence increase. However, the shear damage area of two sides and the distance between the two sides decrease. When the mining thickness is less than 18 m, the peak support pressure in the coal pillar is negatively correlated with the mining thickness. When the mining thickness is greater than 18 m, the peak support pressure in the coal pillar is positively correlated with the mining thickness, but the growth is small. According to the simulation analysis results, it is concluded that the increase of mining thickness is beneficial to the control of the surrounding rock along the two sides of the goaf roadway, but not beneficial to the roof maintenance. For areas with large mining thickness, anchor rods should be added to strengthen support in time. The actual application on site verifies the reliability and validity of the research in this paper.

This paper addresses the trajectory tracking problem for a class of uncertain manipulator systems under the effect of external disturbances. The main challenges lie in the input constraints and the lack of measurements of joint velocities. An extend‐state‐observer is utilized to estimate the velocity signals; then, a neural‐network‐based adaptive controller is proposed to solve the problem, where a term based on the nominal model is included to enhance the tracking ability, and the effect of uncertainties and disturbances are compensated by a neural‐network term. Compared with the existing methods, the main distinctive features of the presented approach are: (i) The control law is guaranteed to be bounded by design, instead of directly bounded by a saturation function. (ii) The trade‐off between the performance and robustness of the presented controller can be easily tuned by a parameter that depends on the size of model uncertainties and external disturbances. By virtue of the Lyapunov theorem, the convergence properties of the proposed controller are rigorously proved. The performance of the controller is validated via both simulations and experiments conducted on a two‐degree‐of‐freedom robot manipulator. [ABSTRACT FROM AUTHOR]

As with many industries, the early life science R&D drug discovery sector is facing growing pressure and higher demands on products in terms of cost, quality, and time‐to‐market. Additionally, the complexity of involved targets and systems, requirements for rapid, safe, and developable candidates are increasing. The drug discovery market, often regarded as rather conservative, relies more and more on advanced technologies. It is therefore a significant task for suppliers to create good solutions that meet customer requirements. The life science industry has a long tradition of using projects as the preferred method to manage these complex systems developments, such as the production of target proteins, screening of compounds, and follow‐up of hit compounds. When applying the project approach, the level of uncertainty is usually high, and the risk of those uncertainties must be managed starting in the early planning phase. Thus, this paper focuses on the issue of how to manage risks in the early project planning phase. We first review state‐of‐the‐art practices in risk management for complex systems project management and identify an important framework, Novelty‐Technology‐Cost‐Pace (NTCP), and apply it to successful risk management for early life science projects. Through an in‐depth case study in the life science industry, we demonstrate a systemic integration of the NTPC framework into project planning. [ABSTRACT FROM AUTHOR]