Defect Engineering
In article number 2313378, Yuan Wang, Hamidreza Arandiyan, Sibudjing Kawi, and co‐workers summarize defect engineering strategies for generating stacking fault defect in ...metal‐based materials and explored their positive impacts on enhancing catalytic performance for hydrogen production. They provide a comprehensive overview of various applications in electrocatalytic processes by SF‐based materials and valuable insights for advancing sustainable energy technologies.
A two-component, supramolecular polymer blend has been designed using a novel π-electron rich bis-perylene-terminated polyether. This polymer is able to self-assemble through electronically ...complementary π–π stacking interactions with a π-electron-deficient chain-folding polydiimide to afford thermally healable polymer blends. Model compounds were developed to assess the suitability of the deep green complexes formed between perylene residues and chain-folding bis-diimides for use in polymer blends. The polymer blends thus synthesised were elastomeric in nature and demonstrated healable properties as demonstrated by scanning electron microscopy. Healing was observed to occur rapidly at ca. 75 °C, and excellent healing efficiencies were found by tensometric and rheometric analyses. These tuneable, stimuli-responsive, supramolecular polymer blends are compared to related healable blends featuring pyrene-terminated oligomers.
Display omitted
•A π-electron rich, bis-perylene-terminated polyether has been synthesised.•Blending with a chain-folding polyimide leads to self-assembly via π–π-stacking.•Binding constants for the motifs involved were obtained using model compounds.•The resulting elastomeric blend shows thermally-healable characteristics above 75 °C.•Excellent healing efficiencies were found by tensometric and rheometric analyses.
The generalized stacking fault energies of face centered cubic Ni-Mo solid solutions are calculated using the exact muffin-tin orbital method in combination with coherent potential approximation. The ...alloying of Mo in Ni is found to decrease the intrinsic stacking fault energy of the solid solution from 150mJ/m2 (pure Ni) to 50mJ/m2 (17.5at.% Mo) almost linearly. At the same time, the unstable stacking fault energy (the unstable twin fault energy) of the Ni-based solid solution increases (decreases) in a small extent with increasing Mo concentration. Three different twinnability measures are adopted and all indicate a substantially enhanced twinning mechanism in Ni-Mo solid solutions with increasing concentration of Mo. The weaker Ni-Ni bonding at high Mo concentrations is considered to be the main mechanism behind the disclosed phenomena. Segregation of Mo to the fault plane is proved to have strong effect on the generalized stacking fault energy of Ni-based solid solution.
Display omitted
•The alloying of Mo in Ni decreases the intrinsic stacking fault energy of solid solution.•The twinning mechanism is enhanced in Ni-Mo solid solutions with increasing concentration of Mo.•The weaker Ni-Ni bonding at high Mo concentration is the main mechanism.•Segregation of Mo to fault plane has strong effect on the generalized stacking fault energy of Ni-Mo.
Over the past 10 years, 3-dimensional (3-D) wafer-level stacked backside Illuminated (BSI) CMOS image sensors (CISs) have undergone rapid progress in development and performance and are now in mass ...production. This review paper covers the key processes and technology components of 3-D integrated BSI devices, as well as results from early devices fabricated and tested in 2007 and 2008. This article is divided into three main sections. <xref rid="sec2" ref-type="sec">Section II covers wafer-level bonding technology. <xref rid="sec3" ref-type="sec">Section III covers the key wafer fabrication process modules for BSI 3-D wafer-level stacking. <xref rid="sec4" ref-type="sec">Section IV presents the device results.
In this paper, we examine the Rényi entropy rate of stationary ergodic processes. For a special class of stationary ergodic processes, we prove that the Rényi entropy rate always exists and can be ...approximated by its defining sequence at most polynomially; moreover, using the Markov approximation method, we show that the Rényi entropy rate can be exponentially approximated by that of the Markov approximating sequence, as the Markov order goes to infinity. For the general case, by constructing a counterexample, we disprove the conjecture that the Rényi entropy rate of a general stationary ergodic process always converges to its Shannon entropy rate as <inline-formula> <tex-math notation="LaTeX">\alpha </tex-math></inline-formula> goes to 1.
The decision for good stacking positions for incoming containers in an automated container terminal is an important operational problem because it affects the productivity not only for stacking but ...also for later retrieval. This paper proposes an online search algorithm which dynamically adjusts and optimizes a stacking policy by continuously generating variants of stacking policies and evaluating them while they are actually being applied for determining the stacking positions. Simulation experiments show that the proposed algorithm is effective in enhancing the operational productivity, while other offline optimization methods are computationally infeasible to be applied to this problem.
Physical properties of ten single-phase FCC CrxMn20Fe20Co20Ni40-x high-entropy alloys (HEAs) were investigated for 0 ≤ x ≤ 26 at%. The lattice parameters of these alloys were nearly independent of ...composition while solidus temperatures increased linearly by ∼30 K as x increased from 0 to 26 at.%. For x ≥ 10 at.%, the alloys are not ferromagnetic between 100 and 673 K and the temperature dependencies of their coefficients of thermal expansion and elastic moduli are independent of composition. Magnetic transitions and associated magnetostriction were detected below ∼200 K and ∼440 K in Cr5Mn20Fe20Co20Ni35 and Mn20Fe20Co20Ni40, respectively. These composition and temperature dependencies could be qualitatively reproduced by ab initio simulations that took into account a ferrimagnetic ↔ paramagnetic transition. Transmission electron microscopy revealed that plastic deformation occurs initially by the glide of perfect dislocations dissociated into Shockley partials on {111} planes. From their separations, the stacking fault energy (SFE) was determined, which decreases linearly from 69 to 23 mJ·m−2 as x increases from 14 to 26 at.%. Ab initio simulations were performed to calculate stable and unstable SFEs and estimate the partial separation distances using the Peierls-Nabarro model. While the compositional trends were reasonably well reproduced, the calculated intrinsic SFEs were systematically lower than the experimental ones. Our ab initio simulations show that, individually, atomic relaxations, finite temperatures, and magnetism strongly increase the intrinsic SFE. If these factors can be simultaneously included in future computations, calculated SFEs will likely better match experimentally determined SFEs.
Display omitted
Correction for 'Stacking interactions by two Phe side chains stabilize and orient assemblies of even the minimal amphiphilic β-sheet motif' by Shlomo Zarzhitsky
et al.
,
Chem. Commun.
, 2015,
51
, ...3154-3157.
We use common conversion point (CCP) stacking of Ps receiver functions to image the crustal structure and Moho of the Garhwal Himalaya of India. Our seismic array of 21 broadband seismometers spanned ...the Himalayan thrust wedge at 79–80°E, between the Main Frontal Thrust and the South Tibet Detachment, in 2005–2006. Our CCP image shows the Main Himalayan Thrust (MHT), the detachment at the base of the Himalayan thrust wedge, with a flat-ramp-flat geometry. Seismic impedance contrasts inferred from geologic cross-sections in Garhwal imply a negative impedance contrast (velocity decreasing downward) for the upper flat, located beneath the Lower Himalaya, and a positive impedance contrast (velocity increasing downward) for the ramp, located beneath the surface trace of the Munsiari Thrust (or MCT-I). At the lower flat, located beneath the Higher Himalaya, spatially coincident measurements of very high electrical conductivities require the presence of free fluids, and we infer a negative impedance contrast on the MHT caused by ponding of these fluids beneath the detachment. Our seismic image indicates that the upper flat of the MHT is ∼10km below sea level and dips north at ∼2°, connecting to a mid-crustal ramp which is ∼10km high and dips at ∼16°. The lower flat is 20–25km below sea level and dips at ∼4°. The Main Central Thrust (MCT) appears as a negative impedance contrast, dipping at ∼16°. The Moho is nearly horizontal at 35–45km depth beneath the Sub-Himalaya and Lower Himalaya, deepening to 50km or more beneath the Higher Himalaya. This depth is 10–25km shallower than in the NW Indian Himalaya and 5–10km shallower than in central Nepal, requiring significant along-strike variations in crustal thickness. The observed thickness of subducted Indian crust in Garwhal is 20–28km.
Display omitted
► We present the first receiver function CCP image of the Garwhal Himalaya, at 79–80°E. ► The Main Himalayan Thrust (MHT) exhibits a complex seismic impedance signature. ► Negative impedances and coincident low resistivities on the MHT imply ponded fluids. ► A ∼16°, NE-dipping ramp in the MHT is present beneath the transition from Lower to Higher Himalaya. ► The thickness of subducted Indian crust in Garwhal varies down-dip between 20 and 28km.
Numerous researchers have developed theoretical and experimental approaches to force prediction in surface grinding under dry conditions. Nevertheless, the combined effect of material removal and ...plastic stacking on grinding force model has not been investigated. In addition, predominant lubricating conditions, such as flood, minimum quantity lubrication, and nanofluid minimum quantity lubrication, have not been considered in existing force models. This work presents an improved theoretical force model that considers material-removal and plastic-stacking mechanisms. Grain states, including cutting and ploughing, are determined by cutting efficiency (β). The influence of lubricating conditions is also considered in the proposed force model. Simulation is performed to obtain the cutting depth (ag) of each “dynamic active grain.” Parameter β is introduced to represent the plastic-stacking rate and determine the force algorithms of each grain. The aggregate force is derived through the synthesis of each single-grain force. Finally, pilot experiments are conducted to test the theoretical model. Findings show that the model's predictions are consistent with the experimental results, with average errors of 4.19% and 4.31% for the normal and tangential force components, respectively.
•Grinding force model based on material removal and plastic stacking mechanism is built.•Dynamic active grains in grinding zone are classified into cutting and ploughing grains.•β presents a S-shaped trend with the increase of ag, ag = 1.18 μm was the critical value.•Tribological tests is conducted to obtain μ under different lubricating conditions.•Model shows 4.19% and 4.31% of the average error for the normal/tangential force.
PDF
