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Byline: Song. Hang, Xu. Kai-Feng, Zhang. Chen-Xi, Zhang. Xiao, Zhang. Zhi-Qiao Three cases of tuberous sclerosis complex (TSC)-associated retinal astrocytic hamartomas (RAH) complicated with vitreous hemorrhage were presented in this [...]

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CO esterification to dimethyl carbonate (DMC) is an attractive route, although the catalyst is the main problem restricting the industrialization of this route. Supported palladium catalysts have been often used for this route. However, the effect of the support is not always clear. In this work, we firstly introduced three metal–organic frameworks (MOFs) materials as catalyst supports, namely UiO-66, MIL-101 and MOF-5, and studied the effect of Lewis acid sites in the MOFs supports on the catalytic activity and selectivity for CO esterification to DMC. Interestingly, the Pd(ii)/UiO-66 catalyst exhibits superior catalytic performance to the other catalysts, with 87.9% CO conversion and 98.5% DMC selectivity due to the abundant Lewis acid sites in UiO-66. It was proven that UiO-66 with more defects would have a large number of Lewis acid sites, and the catalytic performance was positively correlated with the number of Lewis acid sites in MOFs supports, which can be demonstrated by characterization by NH3-TPD, pyridine-IR, XPS and in situDRIRS. The current work not only revealed the relationship between the Lewis acidity of the support and catalytic performance, but also promotes the development of practical catalysts for CO esterification to DMC.

The impact of different trajectory embodiments in terms of velocity profiles on users’ mental stress in close human-robot interaction is investigated. A cooperative assembly scenario is chosen using a standard industrial robot. Conditions are implemented in a repeated measures within-subjects design comparing linear with trapezoidal trajectories. Heart rate variability and galvanic skin conductance are chosen as objective stress markers and evaluated using the average standard deviation of the beat-to-beat intervals (SDNN) and the average skin resistance. Additionally, evaluations of user experience and acceptance are conducted based on evaluated subjective measures. The results of the user study reveal a significant increase of average heart rate variability and average skin resistance in the trapezoidal condition indicating a reduced mental stress level independent of demographical and dispositional factors.

Palladium (Pd)-based catalysts have been widely used for carbonylation of methyl nitrite to dimethyl carbonate (DMC), but a high-performance chloride free catalyst combining both excellent carbon monoxide (CO) conversion and DMC selectivity has not been developed yet. In this work, a chloride free, Pd-based catalyst with good activity and selectivity (conversion of CO: 60.1%, selectivity to DMC: 99.9%) has been successfully fabricated. By thorough characterization and analysis, it is found that the good catalytic activity is positively correlated with the high oxidation states of the Pd species, which could be tuned by their ability to accept the backdonation electron of the ligands. The strong electron backdonation from Pd to π* antibonding orbitals of the ligand in the palladium acetylacetonate [Pd(acac)2] complex accelerates the step where Pdδ+reoxidizes to Pd(ii), resulting in the higher catalytic activity. In addition, a catalytic mechanism was proposed based on the results of X-ray photoelectron spectroscopy and in situdiffuse reflectance infrared spectroscopy. This work not only explains the positive relationship between the catalytic activity and the oxidation state of the Pd species, but also provides a new way to enhance catalytic performance by utilizing the abilities of accepting the backdonation electron of the ligands.

•A model based on deep convolutional neural network is developed to predict the steady-state temperature field in Multichip Modules.•An end-to-end mapping is reconstructed from SDF presented chip placement and power to the temperature field of Multichip Modules.•Fast and accurate prediction with random chip placement is achieved, even under the conditions not included in model training.•A valuable tool is expected for the rapid thermal design of Multichip Modulus.

Low-temperature slab-reheated grain-oriented silicon steel is characterized by a sharp {411}<148> primary recrystallization texture. To date, the influence of this texture on secondary recrystallization is not clear. Micro-textures in primary and secondary recrystallizcd sheets of low-temperature reheated grain-oriented silicon steel were examined using electron backscatter diffraction. By comparing the textures and microstructures of specific primary recrystallized grains neighboring secondary grains with those of other primary grains, the influences of primary recrystallization textures and microstructures on the orientations of secondary grains were investigated. Results show that for low-temperature reheated grain-oriented silicon steel, the primary recrystallization sheet comprises {411}<148>, {111}<112>, and {001}<120> texture components. During secondary recrystallization, the {111}<112> primary recrystallized grains were easily consumed by abnormally grown Goss, deviated Goss, Brass, or {210}<001> grains; the {411}<148> primary recrystallized grains were more resistant to being swallowed; and the {001}<120> grains were the most resistant to being consumed. For a particular primary grain, the distribution of its surrounding grain boundaries determined how easily it is consumed during secondary recrystallization. Primary grains surrounded by 20°–15° grain boundaries were consumed much earlier than those having grain boundaries above 15°, which is in accordance with high-energy grain boundary theory. In addition, special ∑9 boundaries between {111}<148> and Goss grains move more slowly than ∑9 boundaries between {111}<112> and Goss grains, which is attributed to the different positions of <110> rotation axis with respect to the normals of grain boundaries.

(Pd–CuCl2)/γ-Al2O3catalyst with excellent activity and selectivity has been successfully developed for vapor-phase carbonylation of methyl nitrite to dimethyl carbonate (DMC). It has been demonstrated that Cl−is necessary for the superior selectivity (99.8%) to DMC, and that Cl−and Cu2+have a synergetic effect. The Lewis acid sites of the γ-Al2O3support may be suitable for vapor-phase carbonylation of methyl nitrite to DMC. Moreover, the catalytic mechanism of DMC formation on the (Pd–CuCl2)/γ-Al2O3catalyst has been reasonably proposed based on the results of XPS and in situdiffuse reflectance infrared spectroscopy. The intermediate Cl–Pd(ii)–COOCH3is the key factor for the synthesis of DMC.

Pd/MgO catalysts are found, for the first time, to be extraordinarily active and stable for CO oxidative coupling to dimethyl oxalate. A series of Pd/MgO catalysts with Pd loadings of 0.1, 0.3, 0.5, 1 and 2 wt% were prepared by a wet impregnation method and systematically characterized by XRD, TEM, ICP, UV-DRS, H2-TPR and CO2-TPD. It has been demonstrated that the amount of Pd loading has a pronounced effect on the catalytic activity for CO oxidative coupling to dimethyl oxalate. CO conversion increases with the increase of the Pd loading due to high dispersion and similar sizes of Pd nanoparticles, as well as, the increase in number of surface active sites.

This paper describes the dynamics of a liquid blister forced to advance between a thin elastic sheet and a rigid substrate, by the dual action of a piston and a flat frictionless sleeve at the receding end. Compared to the removal of a viscous blister by sliding a frictionless blade (Wang and Detournay, 2021), the present problem is a steady-state one due to the absence of bleeding at the back end. We seek to obtain a travelling-wave solution, in particular the dependence of the external driving force on the blister velocity and other parameters characterizing this problem, such as the fluid viscosity, the elastic properties of the sheet, and the interface toughness. The peculiarity of this problem lays in the Eshelbian (rather than Newtonian) nature of the horizontal driving force applied by the sleeve on the elastic sheet. The Eshelbian nature of this horizontal force is then discussed and alternative expressions of this force are derived from both variational and energy balance considerations. Scaling of the governing equations indicates that the solution depends on three numbers: namely, dimensionless toughness K , residual gap W and length γ f of the fluid-filled part of the blister, a proxy for the volume of the fluid. We use the method of matched asymptotic expansions to predict the horizontal force on a long blister in both the viscosity- and toughness-dominated asymptotic regimes in the back end boundary layer. The numerical solution of the finite blister is then compared with the asymptotic solutions. The key result concerns the dependence of the scaled horizontal force on the three numbers controlling the solution of the moving liquid blister. [Display omitted] • Peculiarity of this problem lays in Eshelbian nature of the horizontal driving force. • Three numbers control the solution of the moving liquid blister. • Matched asymptotic expansion is used to get the long blister asymptotes. • Numerical solutions of the finite blister converge to the long blister asymptotes. [ABSTRACT FROM AUTHOR]

Abstract: In the absence of external loading, surface tension will induce a residual stress field in the bulk of nano structures. However, in the prediction of mechanical properties of nano structures, the elastic response of the bulk is usually described by classical Hooke’s law, in which the aforementioned residual stress was neglected in the existing literatures. The present paper investigates the influences of surface tension and the residual stress in the bulk induced by the surface tension on the elastic properties of nano structures. We firstly present the surface elasticity in the Lagrangian and the Eulerian descriptions and point out that even in the case of infinitesimal deformations the reference and the current configurations should be discriminated; otherwise the out-plane terms of surface displacement gradient, associated with the surface tension, may sometimes be overlooked in the Eulerian descriptions, particularly for curved and rotated surfaces. Then, the residual stress in the bulk is studied through the non-classical boundary conditions and used to construct the linear elastic constitutive relations for the bulk material. Finally, these relations are adopted to analyze the size-dependent properties of pure bending of Al nanowires. The present results show that surface tension will considerably affect the effective Young’s modulus of Al nanowires, which decrease with either the decrease of nanowires thickness or the increase of the aspect ratio. [Copyright &y& Elsevier]

ABSTRACTLight is an important environmental factor for plant growth and development. Phytochrome B (phyB), a classical red/far-red light receptor, plays vital role in controlling plant photomorphogenesis and light-induced stomatal opening. Phytohormone abscisic acid (ABA) accumulates rapidly and triggers a series of physiological and molecular events during the responses to multiple abiotic stresses. Recent studies showed that phyBmutant synthesizes more ABA and exhibits improved tolerance to salt and cold stress, suggesting that a crosstalk exists between light and ABA signaling pathway. However, whether ABA signaling components mediate responses to light remains unclear. Here, we showed that SnRK2.6 (Sucrose Nonfermenting 1-Related Protein Kinase 2.6), a key regulator in ABA signaling, interacts with phyB and participates in light-induced stomatal opening. First, we checked the interaction between phyB and SnRK2s, and found that SnRK2.2/2.3/2.6 kinases physically interacted with phyB in yeast and in vitro. We also performed co-IP assay to support that SnRK2.6 interacts with phyB in plant. To investigate the role of SnRK2.6 in red light-induced stomatal opening, we obtained the snrk2.6mutant and overexpression lines, and found that snrk2.6mutant exhibited a significantly larger stomatal aperture under red light treatment, while the two independent overexpression lines showed significantly smaller stomatal aperture, indicative of a negative role for SnRK2.6 in red light-induced stomatal opening. The interaction of SnRK2.6 with red light receptor and the negative role of SnRK2.6 in red light-induced stomatal opening provide new evidence for the crosstalk between ABA and red light in guard cell signaling.

A fuzzy logic system has been shown capable of arbitrarily approximating any nonlinear function, and has been successfully applied to system modelling. The functional rule fuzzy system enables the input-output relation of the fuzzy logic system to be analysed. B-spline basis functions have many desirable numerical properties and as such can be used as membership functions of fuzzy system. This paper analyses the input-output relation of a fuzzy system with afunctional rule base and B-spline basis functions as membership functions, constructing a neurofuzzy network for systems representation in which the training algorithm is very simple since the network is linear in the weights. It is also desired to merge the neural network identification technique and the Kalman filter to achieve optimal adaptive filtering and prediction for unknown but observable nonlinear processes. In this paper the derived neurofuzzy network is applied to state estimation in which the system model identified is converted to its equivalent state-space representation with which a Kalman filter is applied to perform state estimation. Two approaches that combine the neurofuzzy modelling and the Kalman filter algorithm, the indirect method and direct method, are presented. A simulated example is also given to illustrate the approaches based on real data.

Neurofuzzy algorithms have been extensively developed in recent years for the real time/online identification of nonlinear a priori unknown dynamical processes. As with all rule base paradigms they suffer from the curse of dimensionality, restricting their practical use to low dimensional control problems. This paper shows how adaptive construction algorithms based on additive and extended additive decomposition techniques can overcome this problem, to produce parsimonious neurofuzzy models which retain their transparency or interpretability. Not only does this approach extend the applicability of neurofuzzy algorithms, it also enables low complexity controllers, estimators to be derived. In this context neurofuzzy state estimators are derived which automatically parameterise a Kalman filter for a process state estimate reconstruction from any input/output data source. This approach avoids pitfalls of the extended Kalman filter, and is optimal for local models. The paper discusses real world applications of this new theory of modelling and estimation to helicopter guidance, intelligent driver warning system, communication antennas, autonomous underwater vehicles and an IFAC benchmark problem.