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Non-additive factors can significantly affect the crystallization pathways and hydrate phases of calcium oxalate. However, little is known about the mechanisms behind these phenomena. Our research investigated various factors affecting calcium oxalate crystallization in the absence of additives. We show that the formation of calcium oxalate hydrate phase in a supersaturated solution is inconsistent with thermodynamic stability. The metastable calcium oxalate trihydrate (COT) forms at lower concentrations (<1.25 mM), while the stable calcium oxalate monohydrate (COM) forms at intermediate concentrations, and the metastable calcium oxalate dihydrate (COD) forms at higher concentrations (>20 mM). The formation of the hydrate phase also depends on the method of mixing calcium and oxalate solutions. By utilizing an automatic titration apparatus, we show that the hydrate phase can be altered by adjusting either the titration rate of the calcium solution or the stirring speed. In addition, the calcium-to-oxalate ratio is important in determining the initial binding between calcium and oxalate ions. All these factors could be explained by the local concentration of calcium and oxalate upon mixing the solutions. The reduction of local concentration promotes the formation of COT. Thus, the hydrate phase is determined by a combination of thermodynamic and kinetic factors. These results significantly enhance our understanding of the crystallization pathway and hydrate phase selection of calcium oxalate. [ABSTRACT FROM AUTHOR]

China's function in the establishment of the International Monetary Fund (IMF) and the World Bank (WB) has been underrated for a long time. It is argued either that China contributed little to the establishment or that its main effort could be accredited to Arthur N. Young, an American financial advisor to the Chinese government. A close examination of bilingual archival documents challenges these arguments. In fact, the Chinese government formulated proposals of several versions and managed to have most of its claims accepted at the Bretton Woods conference. More importantly, Chinese claims surpassed their own concerns and had a broader meaning taking into account the general quests of war‐torn and undeveloped countries. Revisiting this part of history can deliver a balance to the traditional Anglo‐American‐focused narrative regarding the IMF and WB and enrich the historical context to assist our understanding of China's current pursuits and conduct in the realm of multilateral economic cooperation. [ABSTRACT FROM AUTHOR]

Understanding the effect of glass network structure on the solubility properties of bioactive glasses is fundamental for designing new compositions with tailored biological functions and applications. This paper bridged the composition-structure-property relationship utilizing experimental measurements and molecular dynamics simulations. The Sr atom reorganized the network structures through a partial transformation of tetrahedral to trigonal boron units and the change of the ratio of bridged oxygen/non-bridged oxygen, which modified the glass structures at longer lengths scales, such as through changing the ring size distribution. Our results demonstrated that the evolution of solubility properties can be linked to the atomic structure change in short- and medium-range ordering. The structure-property relationship can be used to design and tune bioactive glass composition with specific properties. [Display omitted] [ABSTRACT FROM AUTHOR]

The surface-active ILs [C16mim]Cl synthesized by combining imidazole group (C4H6N2) and 1-chlorohexadecane (C16H33Cl) was used as surfactant to prepare ILs microemulsions for sludge treatment. Meanwhile, the treatment conditions were optimized and the optimal conditions were obtained. Due to the strong interaction between ILs and asphaltenes as well as the solubilization of microemulsions, the residual oil rate of oily sludge decreased to 1.33%. The characterization of oily sludge was performed by scanning electron microscope (SEM), fourier transform infrared spectroscopy (FTIR) and contact angle measurement. Results showed that [C16mim]Cl ILs microemulsions treatment could effectively promoted the desorption of asphaltenes from the surface of sludge solids, which provided a clear understanding of the mechanism for ILs microemulsions-enhanced oily sludge recovery. Oil in Water (O/W) microemulsions prepared using ionic liquids [C16mim]Cl as surfactants were used to the treatment of oily sludge with high removal oil rate (97.97%) and low residual oil rate (1.33%). Based on the strong interaction between [C16mim]Cl and asphaltenes as well as the solubilization effect of microemulsions, the use of ionic liquids microemulsions improves the effect of sludge treatment and realizes the effective recovery of crude oil, which has potential applications in the field of energy recovery and environmental protection. [ABSTRACT FROM AUTHOR]

In this work, a novel model reduction technique is proposed, which is based on the hybrid coordinate space modal synthesis method and structural dynamics modification method. This technique can be used to construct the corresponding reduced-order model (ROM) to solve some problems, which focus on the updating of time-varying dynamic parameters for thin-walled components in the milling process. These characteristics of the pending workpiece are analyzed, and then the entire workpiece is divided into two substructure parts: constant workpiece and removed material workpiece. The substructure part of the constant workpiece is analyzed by the double-coordinated free interface method, and the substructure part of the removed material workpiece is analyzed by the finite element method (FEM) among them. Afterwards, the two substructure models in the hybrid coordinate space are coupled based on the interface coordination condition, and the ROM can be obtained about the degrees of freedom (DOFs) of thin-walled components. Moreover, the structural dynamics modification method is introduced, which is used to explore the modal characteristics and vibration response characteristics of the ROM, and is performed to update the dynamic parameters for thin-walled components systems in the milling process. Comparing the dynamical parameters obtained by the full-order model (FOM) method and the reference method under the same conditions, the results indicate that the proposed method can be applied to a variety of boundary conditions effectively, its normalized relative frequency difference (NRFD) values are all lower than 5%, and these values are continuously and stably close to 0. Its modal assurance criterion (MAC) values are all higher than 0.99, and its frequency response assurance criterion (FRAC) values are all 1. For the update speed, its maximum growth rate is 97.38%. Accordingly, the proposed method has nice universality and efficiency, which is embodied in the updating of time-varying dynamic parameters of thin-walled components. [ABSTRACT FROM AUTHOR]

This paper proposes a methodological framework that incorporates probabilistic facility disruption risks, last-mile customers travel path choices, and the induced traffic congestion near the facilities into the consideration of service facility location planning. The customers can be pedestrians, drones, or any autonomous vehicles that do not have to travel via fixed channels to access a service facility. Analytical models are developed to evaluate the expected performance of a facility location design across an exponential number of facility disruption scenarios. In each of these scenarios, customers travel to a functioning facility through a continuous space, and their destination and path choices under traffic equilibrium are described by a class of partial differential equation (PDE). A closed-form solution to the PDE is derived in an explicit matrix form, and this paper shows how the traffic equilibrium patterns across all facility disruption scenarios can be evaluated in a polynomial time. These new analytical results are then incorporated into continuous and discrete optimization frameworks for facility location design. Numerical experiments are conducted to test the computational performance of the proposed modeling framework. • Reliable facility location design under probabilistic facility disruption risks. • Congestion and continuous traffic equilibrium in a continuous space without guideways. • Analytical models to evaluate the expected performance of a facility location design. • System cost across an exponential number of disruption scenarios evaluated in a polynomial time. • Analytical results incorporated into continuous and discrete optimization frameworks. [ABSTRACT FROM AUTHOR]

Diabetic osteoporosis (DO) is a significant complication of diabetes, characterized by a decrease in bone mineral density and an increase in fracture risk. Magnetic nanoparticles (GMNPs) have emerged as potential drug carriers for various therapeutic applications. This study investigated the molecular mechanism of GMNPs loaded with bone marrow mesenchymal stem cell (BMSC) derived extracellular vesicles (EVs) overexpressing MEG3 target miR-3064-5p to induce NR4A3 for treating DO in rats. Initial analysis was carried out on GEO datasets GSE7158 and GSE62589 , revealing a notable downregulation of NR4A3 in osteoporotic samples. Subsequent in vitro studies demonstrated the effective uptake of BMSC-EVs-MEG3 by osteoblasts and its potential to inhibit miR-3064-5p, activating the PINK1/Parkin signaling pathway and thus promoting mitochondrial autophagy, osteoblast proliferation, and differentiation. In vivo, experiments using DO rat models further substantiated the therapeutic efficacy of GMNPE-EVs-MEG3 in alleviating osteoporosis symptoms. In conclusion, GMNPs loaded with BMSC-EVs, through the delivery of MEG3 targeting miR-3064-5p, can effectively promote NR4A3 expression, activate the PINK1/Parkin pathway, and thereby enhance osteoblast proliferation and differentiation, offering a promising treatment for DO. • Revealed the role of the MEG3/miR-3064-5p/NR4A3 axis in Diabetic Osteoporosis (DO). • New application of bone marrow mesenchymal stem cell-derived extracellular vesicles in the treatment of DO. • Verified the potential of GMNP-loaded EVs as a novel drug delivery system. • Demonstrated the critical role of mitochondrial autophagy in bone formation and osteoporosis. • Proposed a new potential method for treating DO. [ABSTRACT FROM AUTHOR]

The 1943 Sino-British treaty negotiations, although widely considered as the end point of British imperialism in China, have not been carefully studied in the current historical works. The negotiations were unexpectedly dominated by the United States rather than the two negotiating parties, either Britain or China. It was due to Washington's initiative and pressure that London finally acceded to an early and broader annulment of its treaty privileges in China. However, the role that the United States played between China and Britain was complicated. Washington was averse to the Nationalists' claims for an earlier reversion of the New Territories of Hong Kong to China. In its opinion, the primary aim of Sino-British and Sino-American treaty negotiations was to improve the tripartite alliance and encourage China's morale in fighting with Japan but not to put an end to British imperialism in China, especially as this carried a risk of deteriorating relations between Britain and the United States. As a result, the end of British imperialism happened earlier in China, but not completely, leaving problems relating Hong Kong and Tibet unresolved. The negotiations demonstrated the complex nature of the China-Britain-American alliance in the initial years of the Pacific War. [ABSTRACT FROM AUTHOR]

Dealing with problems of illumination changes in optical flow estimation, an improved variational optical flow model is proposed in this paper. The local structure constancy constraint (LSCC) is applied in the data term of the traditional HS (Horn & Schunck) optical flow model to substitute the brightness constancy constraint. The fractional-order smoothness constraint (FSC) is applied in the smoothness term of the HS model. Then, the detailed calculation processes from the optical flow model to the optical flow value are explained. The structure tensor in LSCC is an image feature that is constant in the illumination changes scene. The fractional differential coefficient in FSC can fuse the local neighborhood optical flow vector into the optical flow vector of the target pixel, which can improve the integrity of the motion region with the same motion speed. Combining LSCC with FSC, our improved optical flow model can obtain an accurate optical flow field with clear outline in the illumination abnormity scene. The experimental results show that, compared with other optical flow models, our model is more suitable for the illumination changes scene and can be employed in outdoor motion detection projects. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to propose an automatic leveling method for a printing platform based on a three-point coordinate feedback. The proposed method is used in fused deposition modeling additive manufacturing systems. The coordinate error of the leveled plane is constrained to within  ± 0.2 mm, which is less than the printed layer thickness. Design/methodology/approach: First, the model of the forward and inverse solutions of the parallel arm is obtained based on the principles of vector algebra. Second, the automatic leveling mechanism for collecting the z-coordinate is designed. The best position of the virtual origin plane is obtained by comparing the z-coordinates of the test points. Finally, after making multiple adjustments through a closed-loop z-coordinate feedback, the parallelism of the printing plane and the virtual origin plane is limited to an effective range. Findings: The experimental results show that after three leveling attempts, the z-coordinate of the test points can be constrained to within  ± 0.2 mm, which shows that this method can effectively achieve automatic leveling in a delta three-dimensional (3D) printer. Originality/value: This study presents a novel and distinctive delta 3D printer leveling system by designing a leveling mechanism and a leveling algorithm. The method uses a closed-loop feedback mode to make the leveling process simple, convenient and efficient without requiring major changes to the printer. The error after leveling is less than the printed layer thickness, which fully guarantees the accuracy of the leveling process. [ABSTRACT FROM AUTHOR]

Highlight • SnS hollow microspheres are used as counter electrode in dye-sensitized solar cells. • The synthesis method of SnS@RGO is simple and easy to operate. • SnS@RGO achieves high conversion efficiency (8.21%) and exceeds Pt's value (7.75%). Abstract The well-proportioned SnS hollow microsphere has been prepared on reduced graphene oxide (RGO) to form SnS@RGO composite, which are applied to the counter electrode (CE) in dye-sensitized solar cells (DSSCs), and the power conversion efficiency (PCE) of 8.21% is obtained, which is higher than 7.75% in the case of Pt, indicating a faster reaction rate of charge transfer and excellent catalysis of iodide ion for SnS@RGO. It show that SnS@RGO is a promising composite material in the field of CE. [ABSTRACT FROM AUTHOR]

To set up an automatic hot test platform of gyrotron traveling wave tubes (gyro-TWTs), feedback controls of proportional–integral–derivative (PID) were applied. Simulation of the controlling process of operating voltage on the gyro-TWT cathode had been carried out by MATLAB and then was verified as well as compared by the hot test experiment. The PID control on cathode–anode voltage is typical and similar to the control of beam current achieved by the heater filament. The operating voltage controlling process includes two different stages, i.e., the voltage rise and voltage maintenance phase. By optimizing the operating parameters of the PID algorithm, the simulated voltage rise has a good agreement with the one in the hot test controlling. Furthermore, PID responses after feedback control with sinusoidal and random fluctuations are, respectively, investigated. This paper indicates that the proposed strategy can easily achieve a stable operating voltage. [ABSTRACT FROM AUTHOR]

Microstructural evolution and mechanical properties of an ultra‐high strength structural steel welded joint at different heat inputs are investigated by metal active gas arc (MAG) welding technique. It is found that the microstructure of weld metal (WM) contained high volume fraction of acicular ferrite regardless of heat input. However, the acicular ferrite changes from bainite acicular ferrite (B‐AF) to Widmanstätten acicular ferrite (WF‐AF) with the increase in heat input. The microstructure of coarse grain heat affected zone (CGHAZ) is characterized by complete martensite, a mixture microstructure (lath martensite and bainite), and granular bainte, respectively, with increasing heat input from 7.5 to 10.5 and then to18.5 kJ cm−1. The acicular ferrite in WM nucleated at complex oxide inclusions and the number density of inclusions with the size of ≈0.6–1.2 µm significantly increases with the increase in heat input. The maximum drop of strength (113 MPa) occurs when the heat input is up to 18.5 kJ cm−1. High volume fraction of acicular ferrite in WM improves the impact toughness because of increased proportion of high angle grain boundaries and interlocking structure. The heat input should be higher than 7.5 kJ/cm to avoid the formation of welding cold crack and twinned martensite in CGHAZ. [ABSTRACT FROM AUTHOR]

Herein, a simple one-step immersion plating method is firstly used to prepare CuSn/Sn composite film electrode for lithium ion battery and thiourea (TU) is used as potential adjustment agent in the deposition process. The films with different morphologies are obtained by changing the content of tin(II) chloride (SnCl). After a series of physical and electrochemical characterizations, the results demonstrate that the content of SnCl in the plating solution plays an important role in determining the morphology and component of film electrode. In the condition of SnCl 6.5 g L, film electrode obtains both void space to accommodate volume expansion and stable structure which could inhibit abscission of active material from current collector. Therefore, the film electrode has an excellent areal capacity of 0.84 mA h cm after 70 cycles. In comparison with reported Sn-Cu alloy planar film electrodes for lithium ion battery in recent decade, the film electrode in this work exhibits a higher areal capacity. [ABSTRACT FROM AUTHOR]

It is of great importance in many applications to provide a stable output power of a gyrotron-traveling wave tube (gyro-TWT) during a long operation time (over several hours). In order to achieve this goal, an automatic hot test platform of gyro-TWTs was set up and the power stabilization was obtained by an adaptive scheme of proportional integral derivative (PID) feedback by the beam current controlled by the filament heating power and cathode-anode beam voltage. With determined operating parameters, the PID controller can adaptively adjust the beam current and voltage, and then maintain the output power on a target. This PID controlling process can effectively eliminate the influence of the power supply voltage surge and cathode emission instability. Automatic hot test of the gyro-TWTs shows that the PID feedback controlling accuracy of the output power is better than 2%. [ABSTRACT FROM AUTHOR]

Formation mechanism of β"-Mg 5 Si 6 and its PFZ in an Al-Mg-Si-Mn alloy was studied by the means of experiment and first-principles calculations. Results show that at 270 °C during the 100 °C/h heating period, β"-Mg 5 Si 6 precipitated inside the dendrites, whereas precipitation free zones (PFZs) of β"-Mg 5 Si 6 presented near the dendrite arm regions. The formation of the β"-Mg 5 Si 6 and its PFZ were related to the concentration of vacancy. Low-concentration zones of vacancy formed near the eutectics during the solidification due to the constitutional supercooling, no β"-Mg 5 Si 6 precipitated in the low-concentration zones of vacancy due to the vacancy-dependence of β"-Mg 5 Si 6 , the Si vacancy-containing β"-Mg 5 Si 6 was extremely unstable and Si vacancies prefer to stay away from distribution. • At 270 °C during the 100 °C/h heating, β"-Mg 5 Si 6 precipitated inside the dendrites, whereas precipitation free zones (PFZs) of β"-Mg 5 Si 6 presented near the dendrite arm regions. After homogenization at 430 °C for 6 h, α-Al(Fe , Mn)Si dispersoids formed inside the dendrites while the PFZs of α-Al(Fe , Mn)Si were located near the dendrite arm regions. • The element of Mg and Si at the regions near the dendrite arms were higher than the regions inside dendrites, which excluded the possibility that the β"-Mg 5 Si 6 PFZ was attributed to the lack of alloying elements. • Low-concertation zones of vacancy formed near the eutectics during the solidification due to the constitutional supercooling, no β"-Mg 5 Si 6 precipitated in the low concertation zones of vacancy owing to the vacancy acted as the nucleation sites for the precipitation of β"-Mg 5 Si 6. • The results of first-principles calculations show that the Si vacancy-containing precipitates are extremely unstable and Si vacancies prefer to stay away from distribution, which further confirmed the vacancy-dependence of β"-Mg 5 Si 6 precipitation and explained the formation of PFZs of β"-Mg 5 Si 6 and α-Al(Fe , Mn)Si dispersoids. [ABSTRACT FROM AUTHOR]

The chemical composition and lattice parameter of the nanometer-sized carbides in ferrite of Nb-V bearing low-carbon steel were studied by high resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy. The results indicate that the average size of the carbides increased with increase in isothermal holding time. V was found to be gradually incorporated into NbC lattice to form a complex (Nb x V 1−x )C particle during precipitation and the atomic ratio of V/Nb gradually increased during coarsening, which leads to a decrease in the lattice parameter of carbide and reduces the misfit strain between the carbide and ferrite matrix, resulting in acceleration of precipitation kinetics. [ABSTRACT FROM AUTHOR]

Hydrophobic dialdehyde starch (HDAS) was synthesized by dialdehyde starch (DAS) and eighteen-alkyl primary amine as the raw material in DMSO. The effect of the reaction conditions on the yield of HDAS was investigated such as catalyst content, reaction temperature, reaction time, and the in-feed molar ratio of -CHO/-NH2. Moreover, the optimized test parameters were obtained by conducting orthogonal experiment. The molecular structure and the morphology of HDAS were characterized via Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). And the thermal stability and the hydrophobic properties of HDAS were investigated by thermal gravimetric analyzer (TG) and the hydrophobic testing. The results indicate that the yield of HDAS is the highest up to 44.21%, with feed composition 1 : 0.9, reaction temperature 40°C, reaction time 8 h, and acetic acid content 3%. And the introduction of the long-chain alkyl groups into the DAS backbones will ameliorate efficaciously the thermal stability and the hydrophobic properties of DAS, which almost has no effect on the DAS particle size. [ABSTRACT FROM AUTHOR]

Bridgman-type directional solidification experiments were conducted for the TiAl–Nb alloys. The microstructure, phase transition and the hardness were investigated for the composition design. The S- and β-segregation are observed corresponding to solute Nb enrichment in primary β/α phase during the solidification and in the retained β phase during the β → α transition respectively. The improved Nb addition can promote the L + β + α peritectic solidification to the fully β solidification in Ti–46Al alloy, and even the fully α solidification to the β solidification in Ti–50Al alloy. During the peritectic solidification the S-segregation and the further β-segregation lead to the highly solute enrichment and the inhomogeneous multi-phase structure, in which B2 phase and massive γ lamellar from the Nb enrichment in the core of dendrites and the coarse α 2 /γ lamellar from the Al enrichment in the interdendritic region greatly decrease the hardness in TiAl–Nb alloy, leading to the scatter mechanical properties. Finally the low-(Al, Nb) TiAl–Nb alloy with the fully β solidification is proper for the favorable mechanical property due to its homogeneous microstructure with the weak solute segregation. [ABSTRACT FROM AUTHOR]

This paper presents two modeling approaches for median-type facility location design under elastic customer demand and traffic equilibrium in a continuous space. The first approach, following the continuum approximation scheme, builds upon the special case of an infinite homogeneous plane where traffic equilibrium can be described by an ordinary differential equation. The solution to this homogeneous case, sometimes in a closed form, is then used to develop approximate solutions to more general cases (e.g., those in a heterogeneous space). This model provides a computationally efficient way to obtain managerial insights and near-optimal solutions, especially for large problem instances. We also develop a more traditional discrete location model in the form of a mixed-integer program, which builds directly upon a nonlinear partial differential equation description of customer traffic equilibrium. We develop a Lagrangian relaxation based solution approach with an embedded finite-element method subroutine, to separate and solve the location decisions as well as the traffic equilibrium. Numerical experiments are conducted to illustrate applicability of the proposed models and to compare performance of the two complementing modeling approaches. [ABSTRACT FROM AUTHOR]

Drivers' car-following behavior, coupled with inaccurate perception of ambient conditions, contributes to oscillations and significant emissions in congested highway traffic. The emergence of intelligent vehicles and modern communication technologies provides an opportunity to reduce adverse impacts of human factors and dynamically control car-following vehicles. This article proposes a nonlinear model predictive control (MPC) approach for emission mitigation via longitudinal control of intelligent vehicles in a congested platoon. To relieve the real-time optimization burden, we also propose an instantaneous control model which is essentially a simplified MPC approach with a short and identical prediction and control horizon. The proposed vehicle control strategies are tested using a series of simulations, and results verify that localized and instantaneous control of a few intelligent vehicles could reduce emissions of a platoon of vehicles. The proposed models are also applied to field trajectory data, and results show that the instantaneous emission optimization model significantly reduces emissions without increasing travel time. The effectiveness of the proposed vehicle control on emission mitigation and traffic stabilization is found to increase with the percentage (penetration rate) of intelligent vehicles in the congested vehicle platoon. [ABSTRACT FROM AUTHOR]

Bridgman-type directional solidification experiments were conducted for Ti–50Al–4Nb alloy. The continued growth of the non-preferred primary phase with the effect of the growth rate was investigated for the parallel lamellar structure. The planar–cellular–dendritic growth of primary α phase is observed with increasing growth rate and α 2 /γ lamellar structure is obtained finally. The growth of the non-preferred crystals is blocked by the nucleated preferred crystals at low growth rates (<3 μm/s) due to the external particles, as well as that at high growth rates (⩾15 μm/s) due to the tilting crystals and the high undercooling. While the continued growth of the non-preferred crystals is achieved at proper middle growth rates, which always takes on a slope form owning the developed lateral dendrites. Finally the parallel columnar crystals with the parallel lamellar structure are obtained at selected growth rates (5–7 μm/s) by controlling the continued growth of the preliminary non-preferred crystals at the initial interface. [ABSTRACT FROM AUTHOR]

Antibacterial and antioxidant monomethyl fumaric acid (MFA) was selected to modify chitosan, using aqueous solution of an ionic liquid as a homogeneous and green reaction media. The chemical structures of resulting polymers were systematically characterized by 1 H NMR, diffusion ordered spectroscopy, solid 13 C NMR and wide-angle X-ray diffraction. The results show that two kinds of MFA modified chitosan materials with totally different chemical structures have been synthesized. One product was a MF-chitosan salt composed of chitosan cation and MFA anion, which was obtained with the mediation of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N -hydroxysuccinimide. The other one synthesized with the mediation of EDC was a MF-chitosan amide in which MFA and chitosan are covalently attached. Solubility of chitosan has been improved, and MF-chitosan salt can be readily dissolved in water. The antioxidant activity has been enhanced with the introduction of MFA, irrespective of the chemical structure. [ABSTRACT FROM AUTHOR]

Four copper(II) complexes and one copper(I) complex with pyridine-containing pyridylalkylamide ligandsN-(pyridin-2-ylmethyl)pyrazine-2-carboxamide (HLpz) andN-(2-(pyridin-2-yl)ethyl)pyrazine-2-carboxamide (HLpz?) were synthesized and characterized. The X-ray crystal structures of [Cu2(Lpz)2(4,4?-bipy)(OTf)2] (1, OTf?=?trifluoromethanesulfonate, 4,4?-bipy?=?4,4?-bipyridine) and [Cu(Lpz)(py)2]OTf·H2O (2, py?=?pyridine) revealed binuclear and mononuclear molecular species, respectively, while [Cu(Lpz)(?2-1,1-N3)]n(3), [Cu(Lpz?)(?2-1,3-N3)]n(4), and [Cu(HLpz)Cl]n(5) are coordination polymer 1-D chains in the solid state. [ABSTRACT FROM PUBLISHER]

Abstract: The present investigation is aimed to understanding the influence of the morphologies and quantity of ferrite which was obtained by different thermomechanical controlled processes (TMCPs) on microstructure, mechanical properties and three-body impact abrasive wear behavior in a 0.27wt% C low alloy dual phase steel. The results indicate that acicular ferrite which was obtained by controlled rolling at the low temperature with laminar cooling was partially retained after intercritical heat treatment, and leading to much better mechanical properties and abrasion resistance than in the case of polygonal ferrite. Little retained finer acicular ferrite in dual phase steel deflects the propagation of cracks and increases the impact toughness and abrasive wear resistance. [Copyright &y& Elsevier]

Widespread application of biodegradablepolyesters is restrained by inferior mechanical properties, highercost, and lack of reactive functional sites for further modification.A new class of multiblock copolymers bearing reactive sites on themain chains, composed of poly(butylene fumarate) (PBF) and poly(butylenesuccinate) (PBS), has been designed and synthesized to enhance thebiodegradability of PBF and expand its application, while retainingthe mechanical properties. The chemical structures of the copolymerswere confirmed by 1H NMR spectra and GPC. The two segmentsare compatible in both the amorphous and crystalline region, and formcocrystals because of their similar nature. The multiblock copolymerspossess satisfactory thermal and mechanical properties. The degradationrate of copolymers is substantially accelerated by the copolymerizationwith PBS. The novel polymer may be directly used as biodegradablematerials or be postfunctionalized to modify the physicochemical propertiesor to endow the polymers with special properties. [ABSTRACT FROM AUTHOR]

Abstract: An ionic liquid, 1-ethyl-3-methylimidazolium acetate (EMIMAc), was synthesized and employed as a homogeneous and green reaction media to prepare chitosan-graft-polycaprolactone (CS-g-PCL) via ring-opening polymerization, using stannous octoate (Sn(Oct)2) as a catalyst. The structures and compositions of copolymers could be facilely controlled by the reaction conditions and feed ratios. The grafting content of polycaprolactone (PCL) could reach as high as 630%. The chemical structures of the copolymers were systematically characterized by 1H NMR, Fourier transform infrared spectroscopy (FTIR) and wide-angle X-ray diffraction (WAXD), while thermal properties were studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The thermal stability and glass transition temperature (T g) of the graft copolymers vary regularly with the change of PCL grafting content. [Copyright &y& Elsevier]

Abstract: Poly(butylene fumarate) (PBF) bearing reactive double bonds on the polymer main chains has been designed and synthesized by coupling with hexamethylene diisocyanate (HDI) under very mild condition. The chemical structure, conformational structure, crystal structure and molecular weight of PBF were systematically characterized by ATR-FTIR, 1H NMR, 13C NMR, GPC and WARD. The thermal properties, mechanical properties and biodegradability of PBF were carefully studied by DSC, mechanical testing and enzymatic degradation. The results of 1H NMR and 13C NMR spectra indicate that no isomerization or Ordelt saturation reaction of trans Cace during the bulk polymerization and the reaction just proceeded in the way we designed. Linear PBF with high-molecular-weight has been successfully synthesized. This new type of uncrosslinked polyester is shown to have many merits such as relatively high melting point (T m), satisfactory processability and good mechanical properties. The impact strength of PBF is higher than 200 J/m; tensile and flexural strength can reach to 41.0 and 26.7 MPa, respectively. [Copyright &y& Elsevier]

Abstract: Two new pyridylbis(imine) ligands 2-((2-methyl-2-(pyridin-2-yl)-3-(pyridin-2-ylmethyleneamino)propylimino)methyl)phenol, HL2, and 2-methyl-2-(pyridin-2-yl)-N 1,N 3-bis(pyridin-2-ylmethylene)propane-1,3-diamine, L3, were synthesized via the Schiff base condensation of 2-methyl-2-pyridin-2-yl-propane-1,3-diamine and either 2-pyridinecarboxaldehyde or 2-hydroxybenzaldehyde. Complexation of Cu(II) ions by HL2 and L3 yielded [Cu(HL2)]2(ClO4)4 (2), and [Cu(L3)](ClO4)2 (3), respectively. The structures and electrochemistry of 2 and 3 were compared to our previously synthesized Cu(II) complex of the ligand 2,2’-(2-methyl-2-(pyridin-2-yl)propane-1,3-diyl)bis(azan-1-yl-1-ylidene)bis(methan-1-yl-1-ylidene)diphenol (H2L1), which coordinates to Cu(II) as a dianion to form [Cu(L1)(CH3OH)] (1). Whereas (L1)2− and L3 form mononuclear complexes with Cu(II) ions, the asymmetric ligand HL2 produces copper dimers in the solid state with the phenolate O atoms bridging between copper ions. Solution magnetic moment measurements and ESI–MS suggest that all three species exist as monomers in solution, although small amounts of dimeric 2 were detected in solution by ESI–MS and EPR spectroscopy. Complexes of all three ligands show similar EPR properties with typical axial spectra. Cyclic voltammetry reveals that the Cu(I)/Cu(II) redox couples of 2 and 3 are shifted to more positive potentials than that of 1, with 3 having the most positive one-electron reduction potential: E 1/2(1)=−1.489V; E 1/2(2)=−1.099V; E 1/2(3)=−0.438V, all versus Fc/Fc +. [Copyright &y& Elsevier]

Widespread application of biodegradable polyesters isrestrainedby various disadvantages such as inadequate thermomechanical properties,high cost, and lack of reactive sites for further modification. Poly(butylenefumarate) (PBF), as a novel and low-cost aliphatic polyester, possessesgood physical properties and reactive double bonds along with thepolymer backbones which can be potentially modified to endow the polyesterwith specific properties. However, the biodegradation rate of PBFis too slow to meet the requirement of practical application. In thiscontribution, amorphous poly(1,2-propylene succinate) (PPS) was copolymerizedwith PBF to decrease the crystallinity (Xc) and accelerate the biodegradability of PBF via chain-extensionwith diisocyanate. The chemical structures of the copolymers wereconfirmed by 1H NMR spectra and gel permeation chromatography(GPC). The crystal structure and physicochemical properties were investigatedby wide-angle X-ray diffraction (WAXD), differential scanning calorimetry(DSC), mechanical testing, and enzymatic degradation in detail. Boththe impact strength and degradation rate of the copolymers are effectivelyimproved by the introduction of amorphous PPS; while the melting point(Tm) and crystallization temperature (Tc) are hardly reduced by the incorporation ofPPS. The novel polymer may be directed used as low-cost biodegradablematerials or be further functionalized with special properties forparticular applications. [ABSTRACT FROM AUTHOR]

Abstract: Two new pyridylalkylamide ligands containing phenol groups appended to the amide, 2-hydroxy-N-(2-pyridylmethyl)benzamide (HLPhOH) and 2-hydroxy-N-(2-pyridylethyl)benzamide (HLPhOH′), were synthesized. Copper(II) complexes of these ligands were synthesized and characterized by X-ray crystallography, ESI-MS, FTIR, UV/Vis, and EPR spectroscopy. When basic Et3N was used to deprotonate the ligands, tetracopper(II) [Cu4(LPhO)4] (1) or dicopper(II) [Cu2(LPhO′)2(CH3OH)2] (3) were formed. When base was not used, mononuclear [Cu(HLPhOH)2Cl2] (2) resulted. Complex 1 possesses a distorted cubane-like structure, with the ligands bridging via the phenoxo oxygen atoms, and the copper atoms possessing a distorted square planar geometry. The ligands in dimeric complex 3 also bridge between copper(II) atoms via the phenoxo oxygen atoms, and the copper atoms are square pyramidal. Monomeric 2 is a tetragonally distorted six-coordinate species with pyridyl N atoms and chloride ligands in the equatorial plane, and long interactions with the amide carbonyl O atoms in the axial positions. [Copyright &y& Elsevier]

Two low carbon steels were hot rolled by thermo-mechanical process (TMCP), and one contains niobium (0.013%), and another does not contain niobium. By the comparison of tested results, it can be found that the yield strength of Nb steel is 55 MPa higher than that of Nb free steel on an average. In addition, the ferrite grain of Nb steel is finer than that of Nb free steel under the same finishing temperature, cooling rate, and final temperature. However, there are no Nb(C,N) particles to precipitate from austenite and ferrite by the observation of transmission electron microscopy (TEM). It can be concluded by theoretical analysis that both the increase of strength and the refinement of ferrite grain of Nb steel result from solid solution Nb atoms. [Copyright &y& Elsevier]

Data-driven deep learning method is the main way to study the condition monitoring of mechanical equipment, in which sufficient labeled signals to train the model parameters is a typical problem. The existing methods to obtain the labeled signals mainly focus on manual marking. For the non-batch impeller processing with variable working conditions, manually marking signals is not the wisest move. To solve this problem, this manuscript puts forward a deep conditional random field neural network (CRFNN) method. This framework fully utilizes the sensitivity of the conditional probability model to adjacent data marker information, and small cross-labeled samples are used to predict the labels of unknown signals. At the same time, the variational autoencoder is used to convert the one-dimensional time series signal into a three-dimensional image, which solves the problem that the empty tool signals have a great impact on the tool wear condition monitoring in the process of impeller blade machining. Experimental results on a CNC machining center demonstrate the effectiveness and feasibility of the proposed method and outperform the existing works under industrial small labeled samples. [ABSTRACT FROM AUTHOR]

The interface heat transfer coefficient (IHTC) at the different casting/shell mold interfaces during the vacuum investment casting process was investigated by measuring the temperatures of K4169 superalloy melt and mold shell during the preheating, transferring, pouring, and solidification processes. The inverse model of ProCAST was used to calculate the interface heat transfer coefficient (IHTC) based on the temperature measurement results. The inverse calculation results show that the heat transfer between the shell mold and the outside air changes from natural convection to forced convection during the transfer process, but the heat transfer between the shell mold and the inside air is consistently natural convection heat transfer. Then, the convective heat transfer coefficient gradually decreases to 0.1 W/m2·K with the vacuum increases and is finally converted to radiation heat transfer at a vacuum of 10-3 Pa. In the early stages of solidification, the IHTC between the shell mold and the casting can reach 16,000 W/m2·K due to the close contact and the large temperature difference between them, and with the thermal expansion of the shell mold and cooling contraction of the casting, the formation of the gap leads to the interfacial heat transfer coefficient gradually stabilizing at 100–200 W/m2·K. The experimental validation results show that the IHTC has a great influence on the accuracy of the prediction of the location and shape of shrinkage porosities in the vacuum investment castings. [ABSTRACT FROM AUTHOR]

Lamellar heterostructure design is widely recognized as a potential method to improve strength and ductility simultaneously of high‐performance steel. However, the high mechanical contrast among soft/hard phase and inharmonic plastic deformation lead to complex fracture mechanisms and limit the improvement of plasticity. Herein, the plasticity and tensile fracture mechanisms of two types of δ‐ferrite and lath martensite heterolamellar steels with and without α‐ferrite are investigated. The sample without α‐ferrite shows a combination of cleavage in δ‐ferrite and dimple zones in the martensite. The microcracks initiate in the martensite early and the then the cleavage fracture occurs in the δ‐ferrite due to the stress concentration. In contrast, the sample with α‐ferrite has lower plasticity. Failure of the samples with α‐ferrite is govern by the microcracks initiating in the interface of martensite/α‐ferrite. Eliminating the impact of the effect of α‐ferrite, the total elongation increases from 8.9% to 11.6%, and the ultimate tensile strength (UTS) increases from 1567 to 1652 MPa. This study investigates the critical factor in plasticity control of dual‐phase heterostructure and promotes the development and application of lamellar structure. [ABSTRACT FROM AUTHOR]

Numerical simulations were conducted based on the smoothed particle hydrodynamics–finite element method coupling method to investigate the damage evolutions and failure mechanism of reinforced concrete impacted by abrasive water jet. The response processes of damage and fragmentation of reinforced concrete were analyzed. The influences of key jet parameters on fracture characteristics of reinforced concrete were obtained. In addition, evolution laws of stress and damage and the failure mechanism of reinforced concrete impacted by abrasive water jet were revealed. The results indicate that the morphologies of broken pits undergo changes in the following sequence: V-shape, U-shape, and hourglass-shape. The broken pit range almost linearly increases with the impact time. Increasing abrasive concentration is more conducive to peeling concrete above steel, but an appropriate concentration is more suitable for cutting steel. Increasing jet diameter can expand the broken pit width, especially its bottom width, and increase damage to concrete below steel. The concrete stresses beneath steel display a raindrop-like distribution pattern. The concrete protective layer mainly suffers from the multiple stepwise damage accumulation failure caused by compressive shear and tensile stresses, and the interface concrete between steel and protective layer undergoes brittle failure due to weak bonding strength and massive stress concentration. The concrete beneath steel mainly undergoes brittle failure due to strong extrusion effect of steel. In addition, the concrete within steel reinforcement framework is influenced by various forces, such as tensile stress and shear stress, leading to occurrence of damage accumulation without failure. The research results would lay the theoretical foundation for abrasive water jet efficiently crushing reinforced concrete. [ABSTRACT FROM AUTHOR]

BACKGROUND: Application of tranexamic acid (TXA) in the treatment of acetabular fractures could reduce intraoperative and postoperative blood loss. OBJECTIVE: To investigate the effect of single and repeated intravenous infusion of TXA on blood loss of acetabular fractures. METHODS: 120 patients with acetabular fractures admitted to our hospital from January 2017 to September 2020 were retrospectively divided into three groups: Patients accepted 1g TXA at preoperative 30 minutes were defined as single TXA group (n = 40); Patients accepted 1g TXA at preoperative 30 minutes and 1g TXA at 3 hours after the start of surgery were defined as repeated TXA group (n = 40); Patients accepted normal saline at preoperative 30 minutes were defined as control group (n = 40). RESULTS: The total blood loss in single TXA group and repeated TXA group were significantly lower than control group, and the total blood loss in the repeated TXA group was significantly lower than single TXA group (P < 0.05). The hidden blood loss from surgery to postoperative 1 day in repeated TXA group was significantly lower than single TXA group and the control group(P < 0.05). No significant differences were observed in the operative time, postoperative transfusion rate and thrombosis rate among the three groups (P > 0.05). CONCLUSION: Repeated TXA is more recommended during acetabular fracture surgery since it can reduce the total blood loss without increasing the operative time, postoperative transfusion rate and thrombosis rate compared with single TXA. [ABSTRACT FROM AUTHOR]

Neobavaisoflavone (NBIF) is a flavonoid, which has a variety of pharmacological activities. However, the mechanism of NBIF in the treatment of osteoporosis still needs further exploration. The differentiation of osteoblast MC‐3T3‐E1 cells after treatment was observed by Alizarin red staining. Cell counting kit‐8 and flow cytometry were used to detect viability, apoptosis, and reactive oxygen species (ROS) levels of treated MC‐3T3‐E1 cells, respectively. Malondialdehyde (MDA), lactate dehydrogenase (LDH), superoxide dismutase (SOD) and glutathione peroxidase (GSH‐Px) were tested by ELISA kits. The expressions of lncRNA MALAT1, MEG3, CRNDE, Runx2, osteocalcin (OCN), osteopontin (OPN), collagen I (col‐I), nuclear Nrf2, cytoplasm Nrf2, heme oxygenase‐1 (HO‐1) and quinone oxidoreductase 1 (NQO1) in treated MC‐3T3‐E1 cells were examined by Quantitative real‐time PCR or Western blot. Dexamethasone (Dex) inhibited the viability of MC‐3T3‐E1 cells, while the appropriate amount of NBIF had no significantly effect on cell viability. Dex downregulated CRNDE expression, whereas NBIF upregulated CRNDE. Overexpressed CRNDE and NBIF reversed the inhibitory effects of Dex on cell viability, differentiation and levels of SOD, GSH‐Px, Runx2, OCN, OPN, col‐I, nuclear Nrf2, HO‐1 and NQO1 while reversing the promoting effect of Dex on apoptosis and the levels of ROS, MDA, LDH and cytoplasm Nrf2 in MC‐3T3‐E1 cells, respectively, but shCRNDE further reversed the effects of NBIF in MC‐3T3‐E1 cells. NBIF protected osteoblasts from Dex‐induced oxidative stress by upregulating the CRNDE‐mediated Nrf2/HO‐1 signaling pathway. [ABSTRACT FROM AUTHOR]

During cooling, the array jet impact can achieve a rapid and uniform cooling of the high-temperature plate. Previous research results mostly focused on single-jet cooling of thin plates, but the complex flow and heat transfer characteristics between multiple jets could not be obtained. To clarify the heat transfer mechanisms and cooling speed fields characteristics in different flow regions, double water-jet impingement experiments were carried out on an AISI 304 austenitic stainless-steel plate with a thickness of 50 mm. The jet exit velocity was set to 2.95, 5.90, 8.06, and 11.80 m/s, while the jet height was set to 50, 150, 250, 350, and 450 mm. Pure water was selected as the working fluid with a constant temperature of 12.8 °C. The results show that a complex trend with sequential increasing, decreasing, and increasing behaviors appears in the wetting front width, upon increasing the wetting region diameter. The confluence fluid was found to reduce the influence caused by different jet velocities and to increase the influence caused by different jet heights. In addition, it was found that an excessive amount of accumulated fluid reduces the heat transfer efficiency during transition boiling. Finally, the correlations between maximum heat flux and average maximum cooling speed were established, which provide useful data for optimizing the cooling technology. [ABSTRACT FROM AUTHOR]

Lithium metal batteries (LMBs) working at subzero temperatures are plagued by severe restrictions from the increased energy barrier of Li‐ion migration and desolvation. Herein, a competitive coordination strategy based on the ternary‐anion (TA) coupling of PF6−, TFSI−, and NO3− toward Li+ to achieve an anti‐freezing electrolyte with rapid kinetics is proposed. Computational and spectroscopic analyses reveal that the repulsive interaction among three anions and the preponderant coordination of the Li+‐NO3− further weaken the involvement degree of other anions in the Li+ solvation structure. As a result, the formulated TA electrolyte exhibits low binding energy of Li+‐anions (−4.62 eV), Li+ desolvation energy (17.04 kJ mol−1), and high ionic conductivity (3.39 mS cm−1 at −60 °C), simultaneously promoting anion‐derived solid electrolyte interphase on Li anode. Assembled Li||LiNi0.8Co0.1Mn0.1O2 cells employing the TA electrolyte exhibit robust capacity retention of 86.74% over 200 cycles at 25 °C and deliver a specific cathode capacity of 103.85 mAh g−1 at −60 °C. This study will enlighten the rational design of multi‐anion electrolytes to tailor the Li+ solvation/desolvation for advanced low‐temperature LMBs. [ABSTRACT FROM AUTHOR]

Redox stimulation at the molecular level has been the focus of many fields, especially in electrofluorochromic (EFC) devices with individually addressable pixels and switching function. In this study, the fluorescent molecule ((1E)-1-((4-(1,2,2-triphenylvinyl)benzylidene)-hydrazineylidene)ethyl)ferrocene (FcMe-TPE) with aggregation-induced emission (AIE) properties was synthesized and mixed with PVA to prepare an EFC hydrogel material (PVA/FcMe-TPE) with high conductivity. The obtained hydrogel exhibited reversible fluorescent switching behavior, which could be achieved by adding a redox agent alternately based on the redox properties of the FcMe-TPE molecule. The fluorescence intensity of the hydrogel increased by 700 times after adding oxidant and could almost return to the initial value by adding reductant. Interestingly, the effect of the oxidant could be replaced by applying a voltage and the hydrogel exhibited good EFC behaviors. When the voltage increased from 0 V to 1 V, the fluorescence intensity of the hydrogel gradually increased and reached the maximum value at 1 V. The obtained fluorescent hydrogels could be customized to different appearance according to needs, and the EFC devices with individually addressable pixels and switching function were fabricated successfully. Finally, by introducing phytic acid (PA), the mechanical strength of the PVA/FcMe-TPE hydrogel was greatly improved without affecting its EFC performance. This study provides a new idea and solution for the intelligent display field, such as advanced anti-counterfeiting and information encryption. [ABSTRACT FROM AUTHOR]

During the quenching of high‐temperature steel plate, Leidenfrost phenomenon takes place, which prevents the coolant from extracting heat from high‐temperature wall. Adding surfactant to the basic fluid can reduce the surface tension, increase the solid–liquid contact area, and ultimately increase the cooling speed. Herein, aqueous solutions of 240 ppm cetyl trimethyl ammonium bromide (CTAB), 600 ppm sodium dodecyl sulfate (SDS), and 56 ppm polyoxyethy‐lene (20) sorbaitan monolaurate (Tween‐20) are used as coolants. Using a 50 mm thick high‐temperature AISI304 stainless steel plate, free surface jet experiments are designed and completed to study the influence of different coolants on the surface heat transfer and internal thermal conductivity. The experimental results show that surfactants can reduce the surface tension, which enhance the wettability of the fluid on the surface, whereas the time it takes for the fluid to completely wet the experimental region is shortened by up to 13.87%. The foaming can increase the width of wetting front and hinder the expansion speed of the wetted region. When aqueous Tween‐20 with low surface tension and low foaming is used as the coolant, the maximum heat flux increases by 12.11%, 7.03%, 9.33%, 7.70%, and 4.41% compared with that of pure water. [ABSTRACT FROM AUTHOR]

Mixed-organic-cation perovskite absorbers as formamidinium doped methylammonium tin iodine (NH 2 CH) 1 - x (CH 3 NH 3) x SnI 3 ( x ≤ 1 ) can provide a pathway to highly efficient lead-free solar cells. Although this class of materials is known to be severely susceptible to degradation, induced among others by enhanced temperatures, humidity and illumination, an improved layer quality in view of crystal size and homogeneity is the key to diminish or even to block certain degradation channels. In this work, we present the fabrication of fully tin-based perovskites via pulsed laser deposition. The morphology is analyzed for different deposition energies and temperatures to find the optimum process window. The thin films already reveal crystalline structure at room temperature, while they are smooth and homogeneous above a critical thickness for carefully adapted deposition parameters. In contrast to the assumption that at elevated temperatures, the crystallinity is improved, and we find that the films reveal a strong organic depletion and simultaneously tin enrichment. As a measure for their suitability to be employed as photovoltaic absorbers, the band gap of the differently doped perovskites is estimated by spectroscopic ellipsometry in the range of 1.3 to 1.4 eV. [ABSTRACT FROM AUTHOR]

Metal–organic chemical vapor deposition (MOCVD) is a key method for scalable synthesis of two-dimensional transition metal dichalcogenide (2D-TMDC) layers. However, it faces several challenges, such as the unintentional co-deposition of carbon impurities resulting from the pyrolysis of metal–organic precursors. This study investigates the chemical features of carbon and its impact on the photoluminescence property and air stability of 2D-MoS2. Using X-ray photoemission spectroscopy (XPS), it was found that the carbon impurities show characteristics similar to those of sp2-bonded graphitic carbon. Upon prolonged (20–40 weeks) exposure to the atmosphere, the incorporated carbon appears to react with 2D-MoS2, forming a MoS2−xCx solid solution. At the same time, a gradual decrease in the S/Mo ratio implies the formation of sulfur vacancies was also observed. These two processes lead to crystal degradation over time, as evidenced by the gradual quenching of the Raman and photoluminescence (PL) peaks. More detailed PL analyses suggest a charge transfer mechanism between sp2-carbon/2D-MoS2 and 2D-MoS2/air-adsorbates, which, in the short term, could alter PL emissions and appear to further intensify the degradation of 2D-MoS2 in the long-term. The findings highlight the strong impact of unintentionally co-deposited carbon on the optical properties and air stability of MOCVD 2D-MoS2 layers. [ABSTRACT FROM AUTHOR]

Compared to conventional martensitic wear‐resistant steels of the same hardness, high‐titanium wear‐resistant steels with in situ TiC particles can significantly improve wear resistance. However, micron‐sized TiC particles will decrease the toughness of high‐titanium wear‐resistant steels. Here, in order to improve wear resistance without reducing impact toughness, we incorporate 0.0025% cerium elements into high‐titanium wear‐resistant steels. Compared with no cerium steel, the steel containing cerium is demonstrating comparable mechanical properties, with the yield strength of 1283 MPa and impact toughness of 35.6 J, and the wear performance of the steel containing cerium is 1.78 times that of the steel with no cerium. The results show that with the addition of cerium the effective grain size of the steel decreases, and yield strength and toughness increase. The addition of cerium can form intermetallic compounds of Ce2O2S, which are used as heterogeneous nuclear particles in TiC to form rare earth composite particles calculated by the 2D mismatch theoretical model of Bramfitt. As the average spacing of the reinforcing phase particles in the steel decreases, the effective grain size of the steel decreases, and the number of reinforcing phase particles increases, the wear resistance of the steel with the addition of cerium is optimized. [ABSTRACT FROM AUTHOR]

Various substances that possess liquid states include drinking water, various types of fuel, pharmaceuticals, and chemicals, which are indispensable in our daily lives. There are numerous real-world applications for liquid content detection in transparent containers, for example, service robots, pouring robots, security checks, industrial observation systems, etc. However, the majority of the existing methods either concentrate on transparent container detection or liquid height estimation; the former provides very limited information for more advanced computer vision tasks, whereas the latter is too demanding to generalize to open-world applications. In this paper, we propose a dataset for detecting liquid content in transparent containers (LCDTC), which presents an innovative task involving transparent container detection and liquid content estimation. The primary objective of this task is to obtain more information beyond the location of the container by additionally providing certain liquid content information which is easy to achieve with computer vision methods in various open-world applications. This task has potential applications in service robots, waste classification, security checks, and so on. The presented LCDTC dataset comprises 5916 images that have been extensively annotated through axis-aligned bounding boxes. We develop two baseline detectors, termed LCD-YOLOF and LCD-YOLOX, for the proposed dataset, based on two identity-preserved human posture detectors, i.e., IPH-YOLOF and IPH-YOLOX. By releasing LCDTC, we intend to stimulate more future works into the detection of liquid content in transparent containers and bring more focus to this challenging task. [ABSTRACT FROM AUTHOR]

Herein, thermomechanically controlled processing (TMCP) and direct‐quenching (DQ) process are investigated to improve the mechanical and wear properties of wear‐resistant steel, compared to the reheating–quenching (RQ) process. Scanning electron microscope, electron backscatter diffraction, transmission electron microscope, and X‐ray diffraction are employed to characterize the microstructures of the DQ and RQ specimens, and the mechanical and wear properties are investigated using the Vickers hardness, impact, tensile, and stirring wear tests for both processes. The results show that DQ steel exhibits strong plasticity, impact toughness, and wear resistance; the DQ process also retains the deformed austenite formed by rolling in the nonrecrystallization region. The compressed austenite reduces the size of the martensite lath and block structure, increases the density and proportion of the high‐angle grain boundaries, and improves the plasticity and toughness of DQ steel. Meanwhile, DQ steel also inherits the high‐density dislocations created during the rolling process, which is its primary strengthening mechanism. The deformed grains in DQ steel reduce the Schmid factor, improve resistance to wear deformation, and enhance its wear performance. [ABSTRACT FROM AUTHOR]

The authors describe here the relationship between the microstructure and mechanical properties of Ti-Zr killed low-carbon steels based on hot-rolling experiments and thermo-mechanical simulation. High-temperature hot-rolling and controlled cooling are carried out. Microstructural evolution is studied in quenched steels subjected to hot-rolling simulation. The study suggests that non-metallic inclusions in steel are (Ti, Zr)-rich and are effective in promoting nucleation of acicular ferrite in the recrystallized austenite grains such that the as-rolled microstructure is significantly refined in spite of coarse austenite grain size induced by high-temperature rolling. The addition of boron and accelerated cooling also favored nucleation of acicular ferrite. The tensile strength and low-temperature impact toughness is significantly improved in comparison to the Al-killed steel. The microstructural evolution is divided into two stages including formation of interlocking acicular ferrite structure and coarsening of the ferrite plates with the decomposition of residual austenite. [ABSTRACT FROM AUTHOR]