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Background: Observational data indicates a connection between emotional discomfort, such as anxiety and depression, and uterine fibroids (UFs). However, additional investigation is required to establish the causal relationship between them. Hence, we assessed the reciprocal causality between four psychological disorders and UFs utilizing two-sample Mendelian randomization (MR). Methods: To evaluate the causal relationship between four types of psychological distress (depressive symptoms, severe depression, anxiety or panic attacks, mood swings) and UFs, bidirectional two-sample MR was employed, utilizing single nucleotide polymorphisms (SNPs) associated with these conditions. Both univariate MR (UVMR) and multivariate MR (MVMR) primarily applied inverse variance weighted (IVW) as the method for estimating potential causal effects. Complementary approaches such as MR Egger, weighted median, simple mode, and weighted mode were utilized to validate the findings. To assess the robustness of our MR results, we conducted sensitivity analyses using Cochran's Q-test and the MR Egger intercept test. Results: The results of our UVMR analysis suggest that genetic predispositions to depressive symptoms (Odds Ratio [OR] = 1.563, 95% Confidence Interval [CI] = 1.209–2.021, P = 0.001) and major depressive disorder (MDD) (OR = 1.176, 95% CI = 1.044–1.324, P = 0.007) are associated with an increased risk of UFs. Moreover, the IVW model showed a nominally significant positive correlation between mood swings (OR: 1.578; 95% CI: 1.062–2.345; P = 0.024) and UFs risk. However, our analysis did not establish a causal relationship between UFs and the four types of psychological distress. Even after adjusting for confounders like body mass index (BMI), smoking, alcohol consumption, and number of live births in the MVMR, the causal link between MDD and UFs remained significant (OR = 1.217, 95% CI = 1.039–1.425, P = 0.015). Conclusions: Our study presents evidence supporting the causal relationship between genetic susceptibility to MDD and the incidence of UFs. These findings highlight the significance of addressing psychological health issues, particularly depression, in both the prevention and treatment of UFs. [ABSTRACT FROM AUTHOR]

Designing effective electrocatalysts tailored for targeted reactions requires fundamental insights into the structure dependence of the reaction microenvironment. Herein, inspired by finite element simulations, N,O co‐doped carbon nanosheets featuring a hierarchical micro/mesoporous structure to form an oxygen‐rich and local alkaline‐like microenvironment for the two‐electron oxygen reduction reaction (2e− ORR) in a neutral medium are designed. The in situ and ex situ test results confirmed that the micro/mesoporous carbon architecture can elevate the local pH and accelerate the generation of intermediates (*O2, *OOH), leading to high‐efficiency H2O2 production. Utilizing this favorable microenvironment, N,O‐CNS0.5 demonstrated exceptional H2O2 electrosynthesis performance in neutral media, achieving a superior H2O2 yield rate (6705 mmol gcatalyst−1 h−1 in a flow cell). Additionally, comparative experiments and density‐functional theory calculations provided confirmation of the bi‐doping of N and O as the active origin responsible for the electrochemical 2e− ORR. This study synergistically manipulates the reaction microenvironment and active sites, providing an opportunity for efficient H2O2 electro‐production in a neutral medium. [ABSTRACT FROM AUTHOR]

The synergistic effects of boron (B) and rare earth (RE) elements on the microstructure and stress rupture properties were investigated in a Ni-based superalloy. The stress rupture lifetime at 650 °C/873 MPa significantly increased with the addition of B as a single element. Furthermore, the stress rupture lifetime reached its peak (303 h), with a certain amount of B and RE added together in test alloys. Although the grain size and morphology of the γ′ phase varied a little with the change in B and RE addition, they were not considered to be the main reasons for stress rupture performance. The enhancement in stress rupture lifetime was mostly attributed to the segregation of the B and RE elements, which increased the binding force of the grain boundary and improved its strength and plasticity. In addition, the enrichment of B and RE inhabited the precipitation of carbides along grain boundaries. Furthermore, nano-scale RE precipitates containing sulfur (S) and phosphorus (P) were observed to be distributed along the grain boundaries. The purification of grain boundaries by B and RE elements was favorable to further improve the stress rupture properties. [ABSTRACT FROM AUTHOR]

The purpose of this experiment was to study the effects of adding Modified Zhizhu Powder to diet on the growth performance, blood routine examination, serum biochemical indexes, and intestinal digestive enzymes of weaned rabbits. Ninety 35-day-old healthy New Zealand white rabbits with similar weight were randomly divided into five groups with six replicates in each group and three rabbits in each replicate. The rabbits in the control group were fed with basal diet, while the experimental group was fed with 2‰ enrofloxacin powder and 1‰, 3‰, and 5‰ Modified Zhizhu Powder, respectively. The pre-test period was seven days, and the formal test period was 14 days. The results showed that compared with the control group, the average daily gain of weaned rabbits in the Modified Zhizhu Powder group increased significantly (P<0.05), the diarrhea rate decreased significantly, and there was no death of rabbits. Compared with the control group, the immune organ index of weaned rabbits in the Modified Zhizhu Powder group increased significantly (P<0.05), and it was dose-dependent. Compared with the control group, the number of white blood cells, lymphocytes, and neutrophils in the Modified Zhizhu Powder group decreased significantly (P<0.05). The content of immunoglobulin in 5‰ Modified Zhizhu Powder group increased significantly (P<0.05). Modified Zhizhu Powder can enhance the secretion of lipase, α-amylase, cellulase, and trypsin in small intestine, and promote the absorption of energy in intestinal tract of young rabbits by up-regulating the gene expression level of glucose transporter in small intestine. The study indicates that the addition of Modified Zhizhu Powder in the diet of weaned rabbits can improve the growth performance, enhance the immune function, reduce the inflammatory level of the body, and improve the digestion and absorption capacity of intestinal tract. The suitable addition level of Modified Zhizhu Powder in diet is 3‰~5‰. [ABSTRACT FROM AUTHOR]

Edge engineering has emerged as a powerful strategy to activate inert carbon surfaces, and thus achieve a notable enhanced electrocatalytic activity. However, the rational manipulation of carbon edges to achieve enhanced catalytic performance remains a formidable challenge, primarily hindered by immature synthesis methods and the obscured understanding of the structure‐activity relationship. Herein, an organic–inorganic hybrid co‐assembly strategy is used to fabricate a series of mesoporous carbon nanofibers (MCNFs) with controllable edge site densities and the impact of edge population on electrochemical oxygen reduction reaction (ORR) pathways is investigated. The optimized MCNFs catalyst exhibits a remarkable 2e− ORR performance, as evidenced by a high H2O2 selectivity (>90%) across a wide potential window of 0.6 V and a large cathodic current density of −3.0 mA cm−2 (at 0.2 V vs. reversible hydrogen electrode). Strikingly, the density of carbon edge sites can be changed to tune the ORR activity and selectivity. Experimental validation and density functional theory calculations confirm that the presence of edge defects can optimize the adsorption strength of *OOH intermediates and balance the selectivity and activity of the 2e− ORR process. This study provides a new path to achieve high ORR activity and 2e− selectivity in carbon‐based electrocatalysts. [ABSTRACT FROM AUTHOR]

Harnessing solar energy to produce hydrogen peroxide (H2O2) from water (H2O) and dioxygen (O2) via artificial photosynthesis is an attractive route. To achieve high solar‐to‐H2O2 conversion efficiency, herein, an interfacial self‐assembly strategy is adopted to pattern mesoporous resorcinol‐formaldehyde resin (MRF) onto reduced graphene oxide (rGO) to form sandwich‐structured rGO@MRF polymeric photocatalysts. The internal graphene layer that mimics the electron transport chain of plant leaf, can effectively transfer electrons, and promote the two‐electron reduction of O2. Moreover, the mesoporous channels mimic the stomata, beneficially boost the fluid velocity, enrichment of O2, and diffusion of H2O2. Consequently, the developed metal‐free material can achieve an exceptional solar‐to‐chemical energy conversion efficiency of 1.23%. This ingenious interface engineering brings new opportunities for the design of efficient artificial photocatalysts. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study on the resistance law of a rod vertically penetrating different kinds of multilayer granular rafts with a constant velocity so as to reveal the mechanical properties of the multilayer granular rafts. The resistance was quasi-static under the chosen velocity. Experiments were conducted with different granular thicknesses, rod diameters and combinations of particles and liquids. The study shows that the resistance–displacement relation of the rod has three smooth stages. In the first stage, the resistance rapidly increased. In the second stage, the resistance curve maintained an almost constant slope. In the third stage, the resistance smoothly changed with its slope continuously increasing. Based on the corresponding physical models for each stage, the study reveals the exponential dependence of the load-bearing capacity of the multilayer granular raft on its thickness, and clarifies the capillary effects on the resistance law. The study extends the knowledge of the granular raft from monolayer to multilayer structure. [ABSTRACT FROM AUTHOR]

Electrochemical energy storage (EES) devices are expected to play a critical role in achieving the global target of "carbon neutrality" within the next two decades. Potassium‐ion batteries (KIBs), with the advantages of low cost and high operating voltage, and they could become a major component of the required energy‐material ecosystems. Carbon‐based materials have shown promising properties as anode materials for KIBs. However, the key limitation of carbon anodes lies in the dramatic mechanical stress originating from large volume fluctuation during the (de)potassiation processes, which further results in electrode pulverization and rapid fading of cycling performance. Here, a controllable self‐assembly strategy to synthesize uniform dual‐heteroatom doped mesoporous carbon sphere (DMCS) anodes with unique radial pore channels is reported. This approach features a modified Stöber method combined with the single‐micelle template from the molecule‐level precursor design. The DMCS anodes demonstrate exceptional rate capability and ultrahigh cycling stability with no obvious degradation over 12 000 cycles at 2 A g−1, which is one of the most stable anodes. Furthermore, finite element simulations quantitatively verify the stress‐buffering effect of the DMCS anodes. This work provides a strategy from the perspective of stress evolution regulation for buffering mechanical stress originating from large volume fluctuations in advanced KIBs electrodes. [ABSTRACT FROM AUTHOR]

[Display omitted] The 1O 2 -dominated radical pathway is highly active for the complex aquatic environments, but the 1O 2 generation with high efficiency and selectivity is difficult. Herein, iron single-atom catalysts (SACs) supported on graphitized chitin-derived carbon (Fe 1 /NC-700) are synthesized by ball milling combined with high-temperature pyrolysis method using chitin as a carbon and nitrogen source. Fe 1 /NC-700 exhibits excellent catalytic performance and satisfactory stability in the activation of peroxymonosulfate (PMS) for the degradation of acid orange 7 (AO7), the degradation efficiency is 99.8 % within 5 min, and its apparent rate constant k can reach 0.5695 min−1, which is 3 times higher than that of Fe NPs /NC-700. Free radical scavenging experiments, electron spin resonance, in-situ Raman spectroscopy, and electrochemical analyses demonstrate that the degradation process is a 1O 2 -dominated non-radical pathway with the auxiliary participation of Fe(IV)=O and electron transfer, the 1O 2 selectivity is 96.2 %, while Fe(IV)=O and e– are 3.8 %, causing Fe 1 /NC-700 + PMS system exhibits superior anti-interference ability. The reaction mechanism shows that pyrrolic N is the adsorption sites for pollutants, whilst Fe-N x and graphite N are the activation sites for PMS, meanwhile, the graphite N can facilitate the transfer of electron, resulting in the production of large amounts of 1O 2 for the degradation process. [ABSTRACT FROM AUTHOR]

Pomegranate flowers (PFs) were reported to possess various biological activities such as antidiabetic, anti-inflammatory and hepatoprotective activities, and using to treat diabetes. Although chemical constituents and pharmacological activities of PFs have been studied, unfortunately, there was no report on the pharmacokinetic profile of PFs in vivo. In this study, a selective high-performance liquid chromatography triple quadrupole tandem mass spectrometry (HPLC–QQQ–MS/MS) method was developed and validated for simultaneous quantification of four compounds (corilagin, ellagic acid, gallic acid and brevifolincarboxylic acid) in rat plasma after oral administration of PFs. The good linearity concentration ranges for the four analytes were from 2.5 to 3000 ng/mL with coefficient value R 2 > 0.99 in calibration curves. The intra- and inter-day accuracy of the four analytes was in the range of 85.33–102.50%, with relative standard deviation (RSD) of <14.81%. The stability results showed that accuracy of the four analytes was in the range of 81.88–104.74%, with RSD of <14.86%. The validation method was successfully applied to pharmacokinetic profiles of the four analytes in rats after oral administration of PFs extract. This pharmacokinetic study can provide better understanding to clarify in vivo mechanisms of PFs and may facilitate its further development as therapeutic agent. [ABSTRACT FROM AUTHOR]

Stable actinide colloids and nanoparticles are of interest because of their potential to affect the transportation of radionuclides in the near‐field of a nuclear waste repository. At high concentrations, thorium(IV) can precipitate to form intrinsic colloids. In the present study, polynuclear thorium colloids and thorium dioxide crystallites, formed by the condensation of hydrolyzed Th4+ solutions (3 mM; initial pH 5.5) aged for up to 18 months, were studied using small‐angle X‐ray scattering. Scattering profiles were fitted using a unified Guinier/power‐law model (Beaucage model) to extract the radii of gyration and Porod exponents. Analysis of the scattering profiles from a dispersion aged for 5 months indicated that both polymer coils and more compacted structures (radius of gyration Rg ≃ 10 nm) were present, which translated in the Kratky plots as a plateau and a peak maximum, respectively. After 18 months, the SAXS data were consistent with the presence of agglomerates of ThO2 particles suspended in aqueous solution (pH 3.2; [Th] = 1.45 mM). The measured radius of gyration (Rg) of the agglomerates was 5.8 nm, whereas the radius of the ThO2 particles was 2.5 nm. [ABSTRACT FROM AUTHOR]

• A nonlinear kinetic rate model unifies fatigue crack growth from 20 to 650 °C. • The model outperforms Arrhenius, reducing the scatter factor from 5 to 3. • Microscale zig-zag crack paths changes at 20 °C to straight ones at 650 °C. • Local resistance to pure mode I cracking at 20 °C is greatly weakened at 650 °C. This study presents a nonlinear kinetic rate model to describe the temperature-dependence of fatigue crack growth rate (FCGR) of nickel-based superalloys across a wide range (20 to 650 °C). FCGR testing was performed using compact tension specimens of GH4742 superalloy. Metallography analysis on crack growth paths of two tested specimens suggests there is a local resistance to pure model I cracking at 20 °C, which can greatly be weakened at 650 °C. Compared to the classical Arrhenius equation, the proposed model captures the nonlinear temperature-dependence, and yields more accurate results by reducing the scatter factor from 5 to 3. [ABSTRACT FROM AUTHOR]

The efficient electrosynthesis of hydrogen peroxide (H2O2) via two‐electron oxygen reduction reaction (2e− ORR) in neutral media is undoubtedly a practical route, but the limited comprehension of electrocatalysts has hindered the system advancement. Herein, we present the design of model catalysts comprising mesoporous carbon spheres‐supported Pd nanoparticles for H2O2 electrosynthesis at near‐zero overpotential with approximately 95 % selectivity in a neutral electrolyte. Impressively, the optimized Pd/MCS‐8 electrocatalyst in a flow cell device achieves an exceptional H2O2 yield of 15.77 mol gcatalyst−1 h−1, generating a neutral H2O2 solution with an accumulated concentration of 6.43 wt %, a level sufficiently high for medical disinfection. Finite element simulation and experimental results suggest that mesoporous carbon carriers promote O2 enrichment and localized pH elevation, establishing a favorable microenvironment for 2e− ORR in neutral media. Density functional theory calculations reveal that the robust interaction between Pd nanoparticles and the carbon carriers optimized the adsorption of OOH* at the carbon edge, ensuring high active 2e− process. These findings offer new insights into carbon‐loaded electrocatalysts for efficient 2e− ORR in neutral media, emphasizing the role of carrier engineering in constructing favorable microenvironments and synergizing active sites. [ABSTRACT FROM AUTHOR]

With the fast development of mobile Internet, people's social exchange media has transformed from the traditional social network to mobile network. With the explosion of massive information, it has become an interesting topic to detect network user groups with close correlation in the mobile social network. These groups are hidden in the continuously changing relations of social network, and it is very difficult to obtain the information of entire social network. In addition, these social relations are intertwined and complicated under the influence of various networks, and as a result, researches on single-layer network are simple and incomplete. Therefore, this paper proposed a local community detection algorithm for multi-layer complicated network based on the trust relation (MTLCD) to constrain the node tensor. We compared the performance of our algorithm with other classic network clustering algorithms such as GL, LART and PMM in four actual multi-layer network datasets of Bio GRID, Remote sensing, Twitter and Mobile QQ Zone, and the multi-layer modularity was used as the measurement index to evaluate the algorithm performance. The experimental results and analysis prove that: in the MTLCD algorithm, the core node obtained based on the trust relation can better identify the local community in dataset with trust relation. In addition, we also found that this algorithm had higher accuracy and stability, and it can accurately reflect the local community structure which the core node belongs to. [ABSTRACT FROM AUTHOR]

For this paper, boron carbide nanosheets were synthesized using a simple solid-phase thermal reaction with reduced graphene oxide (rGO) aerogel as a carbon source and amorphous boron powder as a boron source. The phase, structure, morphology, and particle size of the prepared B 4 C were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS) and nanoparticle size distribution analysis. The effect of the reaction temperature, reaction time and B/C molar ratio on the crystal structure of B 4 C were also investigated. The results showed that the optimum conditions for the synthesis of B 4 C nanosheets were a reaction temperature of 1450 °C, a reaction time of 4 h and a B/C molar ratio of 4. The resulting nanosheets are hexagonal in shape, with edge lengths of 200–500 nm and an average thickness of about 100 nm. The crystal structure of the nanosheet is rhombohedral. The formation mechanism of the nanosheets is discussed on the basis of the experimental results. In addition, testing the neutron-shielding properties of the B 4 C composites showed that neutron transmittance with a B 4 C nanosheets content of 25 wt% was 94.83% lower (from 56.47% to 2.92%) than with epoxy resin, and the total macroscopic absorption cross-section was 518.41% greater (from 0.2857 ± 0.0023 cm−1 to 1.7668 ± 0.0004 cm−1). Hence, the results of this study identify a lightweight, effective material with excellent neutron-shielding properties. [ABSTRACT FROM AUTHOR]

An axially variable-length solid element with eight nodes is proposed by integrating the arbitrary Lagrangian–Eulerian (ALE) formulation and the absolute nodal coordinate formulation (ANCF). In addition to the nodal positions and slopes of eight nodes, two material coordinates in the axial direction are used as the generalized coordinates. As a consequence, the nodes in the ALE–ANCF are not associated with any specific material points and the axial length of the solid element can be varied over time. These two material coordinates give rise to a variable mass matrix and an additional inertial force vector. Computationally efficient formulae of the additional inertial forces and elastic forces, as well as their Jacobians, are also derived. The dynamic equation of a flexible multibody system (FMBS) with variable-length bodies is presented. The maximum and minimum lengths of the boundary elements of an FMBS have to be appropriately defined to ensure accuracy and non-singularity when solving the dynamic equation. Three numerical examples of static and dynamic problems are given to validate the variable-length solid elements of ALE–ANCF and show their capability. [ABSTRACT FROM AUTHOR]

Abstract An efficient and explicit topology optimization approach is initially proposed for eigenfrequencies of a rotating thin plate in this study. First of all, an accurate dynamic model of the rotating thin plate is established via the thin plate elements of the absolute nodal coordinate formulation (ANCF). When performing the modal characteristic analysis of the rotating thin plate at a prescribed angular velocity, the linear perturbation analysis is employed, during which the coupling between the membrane and bending deformations is considered. The coupling term makes the dynamic model established in the study more accurate than conventional models, especially in the case of large deformations. Then, the moving morphable components (MMC) are used to describe the topology of the plate. In the frame of MMC-based topology optimization, explicit geometrical parameters, positions, and orientations of the components are taken as the design variables so that the total number of the design variables can be greatly reduced. For the topology optimization, the sensitivities of a simple eigenfrequency and multiply repeated eigenfrequencies with respect to a design variable are analytically derived. During the optimization, in order to remove the localized modes in the low-density areas, the mass and stiffness matrices of the thin plate elements of ANCF are carefully penalized. Finally, four numerical examples are presented to validate the proposed topology optimization approach and to demonstrate its effectiveness for two objectives, i.e., maximizing either the first eigenfrequency or the gap between two consecutive eigenfrequencies of a rotating thin plate. Highlights • A new topology optimization approach for eigenfrequencies is proposed. • An accurate dynamic model for a rotating thin plate is established. • The eigenfrequency optimization design of the rotating thin plate is studied. • Two objectives are considered for the topology optimization of the thin plate. [ABSTRACT FROM AUTHOR]

In this study, Yin‐Chen‐Hao‐Tang prepared by two decoction methods, namely, combined decoction (modern decoction method) and separated decoction (traditional decoction method), was analyzed by high‐performance liquid chromatography with quadrupole time‐of‐flight mass spectrometry. The acquired datasets containing sample codes, tR‐m/z pairs and ion intensities were processed with multivariate statistical analyses, such as principal component analysis and an orthogonal partial least squared discriminant analysis model, to globally compare the chemical differences between the different decoction samples. Then, the chemical differences between the combined and separated decoctions were screened out by S‐plots generated from the orthogonal partial least squared discriminant analysis model and compared with chemical information from an established in‐house library. The six components that contributed the most to the chemical differences were identified as chlorogenic acid, caffeic acid, geniposide, genipin, scopoletin, and 3,5‐dicaffeoylquinic acid. The concentrations of genipin and caffeic acid from the separated decoction were higher than those from the combined decoction, indicating that the separated decoction may present a stronger hepatoprotective effect. However, the results still require further investigation through pharmacological and clinical studies. Our findings not only establish a strategy to evaluate chemical consistency of Yin‐Chen‐Hao‐Tang but also provide the scientific basis for using traditional separated decoction method. [ABSTRACT FROM AUTHOR]

Highlights • The proposed method alternately calculates the position and times of the source node that is more computationally efficient. • The convergence behavior of the proposed method is further theoretically proved. • First-order perturbation analysis shows that the performance of the proposed method can approximately reach the CRLB. • Compared with some previous methods, the proposed method requires fewer anchor nodes and less communication cost. Abstract This paper efficiently solves the problem of joint localization and synchronization in wireless sensor networks by using two-way message exchange mechanism. Employing an affine model of unsynchronized local clocks, we first establish the famous Maximum Likelihood (ML) estimator for joint localization and synchronization, which derives the best consistent solution. Unfortunately, achieving directly the ML estimator is usually difficult because the ML cost functions are highly non-linear and non-convex. In order to effectively obtain the ML estimator, a novel bi-iterative algorithm is proposed by alternately searching the sensor node location and clock parameters (clock skew and clock offset). We prove that the proposed algorithm is convergent, and analyze that its estimation accuracy for the sensor node locations and clock parameters can approximately reach the Cramer–Rao Lower Bound (CRLB) under the mild noise condition. Compared with some previous methods, the proposed bi-iterative algorithm is more computationally efficient, and takes fewer anchor nodes and less communication overhead. Simulation results verify theoretical analysis and show that the proposed algorithm has the better performance than the several existing algorithms. [ABSTRACT FROM AUTHOR]

A series of calibration measurements have been performed on Suanni – the first small‐angle neutron scattering spectrometer entering into routine user operation in China – aiming to characterize instrument performance and to provide a reference for user experiments. Various calibration standards were used to verify the precise association of the scattering intensity I with the scattering vector magnitude q at short and medium sample–detector distances. The measurements recorded for silver behenate powder revealed a slight shift of the neutron wavelength (λ) at the sample position as compared to the nominal λ calculated by the selector constant. The deviation was more significant with λ > 0.8 nm owing to the shape of the incoming neutron spectrum incident on the selector. The measured dead time for the entire detection system is 2.7 µs, as determined by measurements with varying fluxes. A protonated/deuterated polystyrene blend was employed as the primary standard to calibrate the secondary standard H2O. The instrument covers an effective q range between 0.013 and 5 nm−1, as demonstrated by scattering curves obtained from a monodisperse poly(methyl methacrylate) nanoparticle suspension and a glassy carbon plate. The wavelength, the scattering vector magnitude and the absolute intensity for the Suanni small‐angle neutron scattering spectrometer have been calibrated by using standard samples, providing an informative reference for users and diagnostic tools for instrument scientists. [ABSTRACT FROM AUTHOR]

An efficient optimization approach is proposed to simultaneously optimize the topology and geometrical sizes of a three-dimensional (3D) variable-length structure. First of all, in a unified global coordinate system, a flexible multibody system (FMBS) model is established to describe the extension and contraction dynamics of a variable-length structure. The variable-length flexible structure is meshed by the proposed arbitrary Lagrangian–Eulerian (ALE) solid elements of absolute nodal coordinate formulation (ANCF). To consider the variable-length behaviors, the classic equivalent static loads (ESL) is redefined by introducing the concept of virtual design domain. With the help of the ESL, the dynamic response optimization of the variable-length structure is turned into a static one. A simultaneous topology and size optimization approach is initially proposed via the moving morphable components (MMC). By appropriately arranging the initial configuration of the components and linking all or part of the design variables of a component with others’, the variable-length structure can be designed as a homogeneous or heterogeneous periodic structure. The approach is numerically implemented via an additional constraint that modifies the sensitivities with respect to some design variables. Finally, three numerical examples are presented to demonstrate the effectiveness and efficiency of the proposed optimization approach. [ABSTRACT FROM AUTHOR]

C8H7N3O, orthorhombic, Pccn (no. 56), a = 9.9071(14) Å, b = 11.1950(19) Å, c = 13.315(2) Å, V = 1476.8(4) Å3, Z = 8, Rgt(F) = 0.0356, wRref(F2) = 0.1034, T = 100(2) K, β = 90°. [ABSTRACT FROM AUTHOR]

Small-angle scattering was employed to characterize the gradual phase mixing and separation of Estane 5703p, a type of polyester polyurethane, as a function of temperature (20–110 °C) and time (minutes to 80 days). The polymer structure was modelled by polydisperse hard spheres, and microstructure evolution of the material was inferred from the development of the fitting parameters. At temperatures higher than 40 °C, the scattering data indicated the mixing of hard domains (MDI-BDO) with soft matrix (PBA). The hard domain distance showed a sharp increase at 50–60 °C. Between 60 and 90 °C, a newly-observed ordering signalled the formation of a distinct mesophase with a repeat distance of 5.15 nm. Upon heating, the morphology evolution in Estane follows: domain intermixing – mesophase formation – final melting. After cooling, the domain structure partly recovered, but did not reach the original state during storage at room temperature for 80 days. [ABSTRACT FROM AUTHOR]

Nowadays, it is known that activated porous carbon materials behave high specific capacitance owing to their high specific surface area, microporous and mesoporous structures. Therefore, the carbon materials with low cost and good cycle stability become one of the most promising electrode materials in supercapacitors. In this paper, the carbon material prepared by the carbonization of wild rice stem and the alkali activation possesses high specific surface area up to 1228 m 2 /g, which makes it more hopeful application prospects in electrochemical field. The results indicate that activation temperature and alkali concentration play important roles in improving the performance of specific capacitance of the activated carbon. The activated porous carbon prepared at 800 °C with a KOH/wild rice stem mass ratio of 3 shows the best performance and displays a specific capacitance of 301 F/g at current density of 1 A/g in a three-electrode configuration. Furthermore, the assembled symmetric supercapacitor attains a high energy density of 13.05 Wh/kg at the power density of 250 W/kg in 6 M KOH electrolyte. So the activated porous carbon made from wild rice stem is a low-cost, eco-friendly and high performance material for supercapacitors. [ABSTRACT FROM AUTHOR]

A comprehensive survey of the literature of the most relevant analytical, numerical, and experimental approaches for the kinematic and dynamic analyses of multibody mechanical systems with clearance joints is presented in this review. Both dry and lubricated clearance joints are addressed here, and an effort is made to include a large number of research works in this particular field, which have been published since the 1960′s. First, the most frequently utilized methods for modeling planar and spatial multibody mechanical systems with clearance joints are analyzed, and compared. Other important phenomena commonly associated with clearance joint models, such as wear, non-smooth behavior, optimization and control, chaos, and uncertainty and links’ flexibility, are then discussed. The main assumptions procedures and conclusions for the different methodologies are also examined and compared. Finally, future developments and new applications of clearance joint modeling and analysis are highlighted. [ABSTRACT FROM AUTHOR]

The most popular way to study the dynamics of a multibody system with random parameters is the probabilistic method under the assumption that the mean values and variances of the random parameters are deterministic. For many engineering systems, however, the mean values and variances of those random parameters are inherently interval parameters. In this work, a new computation method is proposed to study the dynamics of flexible multibody systems with hybrid uncertain parameters, i.e., the random parameters with interval mean values and interval variances. The flexible multibody system of concern is described by using the Absolute Nodal Coordinate Formulation first. Then, the perturbation-based method is developed in order to incorporate hybrid uncertain parameters in the dynamic analysis of flexible multibody systems. Afterwards, the dynamics equations are expanded about the mean values of the uncertain input variables by means of the second-order Taylor series. The Chebyshev collocation method, together with the scanning method, is utilized to generate the interval bounds for the deduced surrogate model. Finally, the interval mean values and interval variances of the system dynamics are obtained by using the interval arithmetic. As a consequence, the proposed method can be degenerated into the pure interval method. [ABSTRACT FROM AUTHOR]

[Display omitted] • Uranyl oxyhydroxide (UOH) films were deposited on silicon substrate. • Hydrolysis of U O 2 2 + by addition of solid Mg(OH) 2 led to metaschoepite. • Metaschoepite surfaces formed at 50 °C/3h were self-affine fractal (D f = 2.5). • M n+ incorporation (wt. %) into metaschoepite: La > Nd > Ce > Eu > Pb ≫ Sr. • Metaschoepite and Na-uranate hydrate were formed in Cl − SO 4 − Na groundwater. Incorporation of fission products in spent nuclear fuel is of interest in the frame of safe storage of high-level nuclear waste in a deep geological repository. Uranyl oxyhydroxide films were grown on silicon wafer to represent the corrosion product formed on the surfaces of the fuel. Films were obtained by hydrolysis of uranyl ions (9 mM) in mild conditions (≤60 °C) using either Mg(OH) 2 , raw brucite, La(OH) 3 , or NH 4 OH to control the solution pH to ≈ 5.0. To identify the mineral phases we used the grazing-incidence X-ray technique. Atomic force microscopy data indicated that the surfaces of metaschoepite films prepared using either Mg(OH) 2 or brucite at 50 °C for 3 h were self-affine fractal (D f = 2.5). The concentration (wt.%) of reactant ions detected in a metaschoepite film after reaction at 70 °C for three days as determined by X-ray fluorescence was: La (8.90) > Nd (5.6) > Ce (3.2) > Eu (2.5) > Pb (0.7) > Sr (0.14). Metaschoepite and sodium uranate hydrate were identified in a film formed in Cl-SO 4 -Na type groundwater from the Beishan area (China), the preselected area of a radioactive waste disposal repository. [ABSTRACT FROM AUTHOR]

In this research, a group of segmented polyurethane (PU) copolymers with different hard segment (HS) contents were successfully synthesized. The microstructure of the PU copolymers was characterized via Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and small-angle neutron scattering (SANS). Then, the PU copolymers were selected as polymer binder for coating an insensitive high explosive 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) to prepare polymer bonded explosives (PBXs). When the HS concentration of PU copolymers increased from 14 to 34 wt %, a 14.6 times increase in the creep rupture time of PBXs under 60 °C/3 MPa and a 52.3% decrease in the steady-state creep strain rate under 60 °C/1 MPa were observed. The experimental results indicated that a wide variety of structure and properties of PU copolymer could be customizable through the adjustment of the HS contents, and consequently, provided an efficient route to tune the creep performance of the PBXs over a wide range. [ABSTRACT FROM AUTHOR]

Soft machine refers to a kind of mechanical system made of soft materials to complete sophisticated missions, such as handling a fragile object and crawling along a narrow tunnel corner, under low cost control and actuation. Hence, soft machines have raised great challenges to computational dynamics. In this review article, recent studies of the authors on the dynamic modeling, numerical simulation, and experimental validation of soft machines are summarized in the framework of multibody system dynamics. The dynamic modeling approaches are presented first for the geometric nonlinearities of coupled overall motions and large deformations of a soft component, the physical nonlinearities of a soft component made of hyperelastic or elastoplastic materials, and the frictional contacts/impacts of soft components, respectively. Then the computation approach is outlined for the dynamic simulation of soft machines governed by a set of differential-algebraic equations of very high dimensions, with an emphasis on the efficient computations of the nonlinear elastic force vector of finite elements. The validations of the proposed approaches are given via three case studies, including the locomotion of a soft quadrupedal robot, the spinning deployment of a solar sail of a spacecraft, and the deployment of a mesh reflector of a satellite antenna, as well as the corresponding experimental studies. Finally, some remarks are made for future studies. [ABSTRACT FROM AUTHOR]

In a unified global coordinate system frame, a new elastohydrodynamic (EHD) lubricated spherical joint model for flexible multibody dynamics is proposed. The proposed joint can be further used to model the human gait artificial hip joints. To mesh the flexible spherical socket of the joint, an isoparametric fifteen-node pentahedron finite element with global nodal position coordinates is introduced. The element elastic forces and their Jacobians are derived using a continuum mechanics approach. The ball within the spherical joint is assumed to be rigid, and it is described using the absolute nodal coordinate formulation reference node (ANCF-RN). The spherical joint lubricant pressure is obtained by solving the Reynolds’ equation using the successive over relaxation (SOR) algorithm. To address the lubrication interface non-conformance problem that exists between the lubricant grid and the socket inner surface node grid, a novel lubricant finite-difference grid rotation scheme is introduced. The assembled equations of motion for the constrained rigid-flexible multibody system with a large number of degrees of freedom are solved using the generalized-alpha algorithm. Finally, four numerical examples are studied to validate the proposed EHD lubricated spherical joint model. Some numerical results are also verified using the commercial software ADINA. [ABSTRACT FROM AUTHOR]

The paper presents how to optimize the flexible components in a flexible multibody system undergoing both large overall motion and large deformation by using the Absolute Nodal Coordinate Formulation (ANCF) and the equivalent static load (ESL) method. Before the structural optimization, the flexible multibody system is modeled via ANCF first so as to describe the coupled overall motion and large deformation accurately. During the structural optimization, the elastic deformation of the flexible component to be optimized is split from the overall motion of the flexible component, and then the equivalent static loads are determined by using the ESL method such that the structural optimization of nonlinear dynamic response can be transformed into a static one. In addition, the nonlinear interior point method is adopted to solve the corresponding structural optimization problem of nonlinear static response. The paper gives three numerical examples to validate the above optimization procedure. The final example of optimizing the arms in a rigid-flexible grasping robot shows that the proposed optimization procedure enables one to deal with realistic engineering systems. [ABSTRACT FROM AUTHOR]

Preparation of Gd 2 Zr 2 O 7 nanoceramics using a simple and low energy-consuming approach is significant for their wide range of applications. In this work, flash sintering (FS) and two-step flash sintering (TSFS) were first utilized to prepare Gd 2 Zr 2 O 7 nanoceramics. The effects of electric field intensity and current limit on the densification and grain growth were investigated. The grain size was decreased with the increase of electric field intensity. Meanwhile, both grain size and density were increased with the increase of current limit. The Gd 2 Zr 2 O 7 nanoceramics with an average grain size of 98 nm and a relative density of 92.8% were prepared by FS. By contrast, the Gd 2 Zr 2 O 7 nanoceramics with the higher relative densities of 96.3–97.5% and the smaller average grain sizes of 85–90 nm were prepared by TSFS. Compared to FS, TSFS can achieve suppressed grain growth and fast densification. The as-prepared Gd 2 Zr 2 O 7 nanoceramics showed excellent hardness and fracture toughness. The sample breakage caused by current localization can be avoided by controlling the current ramp after the occurrence of the flash event. [ABSTRACT FROM AUTHOR]

Under the frame of multibody dynamics, the contact dynamics of elasto-plastic spatial thin beams is numerically studied by using the spatial thin beam elements of absolute nodal coordinate formulation (ANCF). The internal force of the elasto-plastic spatial thin beam element is derived under the assumption that the plastic strain of the beam element depends only on its longitudinal deformation. A new body-fixed local coordinate system is introduced into the spatial thin beam element of ANCF for efficient contact detection in the contact dynamics simulation. The linear isotropic hardening constitutive law is used to describe the elasto-plastic deformation of beam material, and the classical return mapping algorithm is adopted to evaluate the plastic strains. A multi-zone contact approach of thin beams previously proposed by the authors is also introduced to detect the multiple contact zones of beams accurately, and the penalty method is used to compute the normal contact force of thin beams in contact. Four numerical examples are given to demonstrate the applicability and effectiveness of the proposed elasto-plastic spatial thin beam element of ANCF for flexible multibody system dynamics. [ABSTRACT FROM AUTHOR]

Elongated grain is a typical grain morphology and influences the mechanical properties of polycrystalline materials. Directional ultrasonic backscattering signal is sensitive to the grain shape, and the phased array ultrasound provides an effective and efficient means to collect the directional backscattering signals. In this study, the theoretical backscattering model is modified to allow for phased array detection. The model shows that the backscattering amplitude is dependent on the direction of the ultrasound propagation. Experimental testing on an aluminum sample is performed to acquire phased array ultrasound data with multiple steering angles and rotation angles. The experimental directional backscattering ratios are fitted by the theoretical ratios using the least-squares method. The results show that the phased array directional backscattering method can be used to measure the size and shape of elongated grains. The size and shape quantifications of elongated grains obtained using the developed method are comparable to those obtained via metallography. • Phased array ultrasound backscattering model for elongated grains is built. • Influence of shape and size, frequency, and incident angles are analyzed. • Shape and size of elongated grain of Al2024 are quantified using the method. • Comparisons are made with metallography and conventional ultrasound. [ABSTRACT FROM AUTHOR]

The paper mainly applies the information categorization method to analyze the financial time series. The method is used to examine the similarity of different sequences by calculating the distances between them. We apply this method to quantify the similarity of different stock markets. And we report the results of similarity in US and Chinese stock markets in periods 1991–1998 (before the Asian currency crisis), 1999–2006 (after the Asian currency crisis and before the global financial crisis), and 2007–2013 (during and after global financial crisis) by using this method. The results show the difference of similarity between different stock markets in different time periods and the similarity of the two stock markets become larger after these two crises. Also we acquire the results of similarity of 10 stock indices in three areas; it means the method can distinguish different areas’ markets from the phylogenetic trees. The results show that we can get satisfactory information from financial markets by this method. The information categorization method can not only be used in physiologic time series, but also in financial time series. [ABSTRACT FROM AUTHOR]

Adjuvant interferon (IFN) therapy following curative treatment for hepatocellular carcinoma (HCC) has been extensively investigated; however, the clinical benefits with different hepatitis backgrounds remain unclear. Medline, Embase, PubMed and the Cochrane Library databases were searched to identify randomized trials and cohort studies that enrolled HCC patients who received curative surgery or ablation therapy followed by IFN and control subjects; the studies were required to include data on early or late recurrence and mortality rates of HCC. Hepatitis B virus (HBV) associated with HCC (HBV-HCC) and hepatitis C virus (HCV) associated with HCC (HCV-HCC) were separately analyzed and recurrence, mortality and clinicopathological factors were compared. A total of 14 studies (9 randomized trials and 5 cohort studies, including 1,385 patients in total) were eligible for meta-analysis. IFN was found to decrease mortality and early recurrence rates, but exerted no effect on late recurrence rate. The effect of IFN differed between HBV-HCC and HCV-HCC cases. In HCV-HCC, IFN significantly reduced mortality as well as recurrence rates. However, in HBV-HCC patients, IFN reduced mortality rather than recurrence rates, although it also reduced the recurrence rate in certain subgroups. In conclusion, the effect of adjuvant IFN on postoperative recurrence differed between HBV-HCC and HCV-HCC cases; therefore, different strategies with adjuvant IFN should be used to treat HCC with different hepatitis backgrounds. [ABSTRACT FROM AUTHOR]

Background: The novel small molecule R118 and the biguanide metformin, a first-line therapy for type 2 diabetes (T2D), both activate the critical cellular energy sensor 5′-AMP-activated protein kinase (AMPK) via modulation of mitochondrial complex I activity. Activation of AMPK results in both acute responses and chronic adaptations, which serve to restore energy homeostasis. Metformin is thought to elicit its beneficial effects on maintenance of glucose homeostasis primarily though impacting glucose and fat metabolism in the liver. Given the commonalities in their mechanisms of action and that R118 also improves glucose homeostasis in a murine model of T2D, the effects of both R118 and metformin on metabolic pathways in vivo were compared in order to determine whether R118 elicits its beneficial effects through similar mechanisms. Results: Global metabolite profiling of tissues and plasma from mice with diet-induced obesity chronically treated with either R118 or metformin revealed tissue-selective effects of each compound. Whereas metformin treatment resulted in stronger reductions in glucose and lipid metabolites in the liver compared to R118, upregulation of skeletal muscle glycolysis and lipolysis was apparent only in skeletal muscle from R118-treated animals. Both compounds increased β-hydroxybutyrate levels, but this effect was lost after compound washout. Metformin, but not R118, increased plasma levels of metabolites involved in purine metabolism. Conclusions: R118 treatment but not metformin resulted in increased glycolysis and lipolysis in skeletal muscle. In contrast, metformin had a greater impact than R118 on glucose and fat metabolism in liver tissue. [ABSTRACT FROM AUTHOR]

Local electrochemical deposition (LECD) has proved to be an efficient and economical method for fabricating three-dimensional micron structures. Realizing complex structures that join up when deposited using LECD has been complex; therefore, the fabrication of an X-shaped joining structure was investigated in this study. A horizontal trace model was proposed, and the effects of the number of deposition layers and the horizontal sweep width on the merging joint were studied. The horizontal trace model could complete the merging joint. Multiple deposition layers and a large horizontal sweep width could stabilize and better connect the X-shaped structure containing merging joints. The merging mechanism of the X-shaped structure was also investigated using COMSOL. The stable deposition of the joining structure enables the LECD method to have a broader range of applications in micro-nano manufacturing. [ABSTRACT FROM AUTHOR]

Abstract: A coupled thermal–structural analysis based on the Euler–Bernoulli beam model is conducted within a framework of Absolute Nodal Coordinate Formulation. The absorbed heat flux on the beam surface depends on actual deformation and motion of the beam, therefore the coupled transient heat conduction equation and structural dynamics equation are established and solved interactively by the generalized-α scheme. Thermally induced vibrations for a thin-walled tubular boom subjected to a sudden heating in order to simulate spacecraftʼs exit from eclipse, and structure dynamics of a rotating flexible manipulator in a thermal environment are examined in details. With the coupled thermal–structural analysis, the thermal flutter can be well predicted for a cantilever beam moving from eclipse with large incident angles of solar radiation, and the proposed model is also able to characterize the coupled thermal–structural dynamics when a flexible beam is subjected to a large rotation. The developed model can be served as a basic unit for analyzing thermal–mechanical coupling response of large flexible space structures based on the Absolute Nodal Coordinate Formulation. [Copyright &y& Elsevier]

Background: ER+ breast cancer (ER+ BC) is the most common subtype of BC. Recently, CDK4/6 inhibitors combined with aromatase inhibitors have been approved by FDA as the first‐line therapy for patients with ER+ BC, and showed promising therapeutic efficacy in clinical treatment. However, resistance to CDK4/6 inhibitors is frequently observed. A better understanding of the drug resistance mechanism is beneficial to improving therapeutic strategies by identifying optimal combinational treatments. Methods: Western blotting, qPCR, flow cytometry and a series of cell experiments were performed to evaluate the phenotype of MCF‐7/R cells. RNA sequencing, non‐targeted metabolomics, shRNA knockdown and tumour cell‐bearing mouse models were used to clarify the drug resistance mechanism. Results: Here, we found that ER+ BC cells have shown an adaptive resistance to palbociclib‐induced cell cycle arrest by activating an alternative signal pathway, independent of the CDK4/6‐RB signal transduction. Continuing treatment of palbociclib evoked cellular senescence of ER+ BC cells. Subsequently, the senescence‐like phenotype promoted stemness of ER+ BC cells, accompanied by increased chemoresistance and tumour‐initiating potential. Based on transcriptome analysis, we found that PFKFB4 played an important role in stemness transformation and drug resistance. A close correlation was determined between PFKFB4 expression by ER+ BC cells and cell senescence and stemness. Mechanistically, metabolomic profiling revealed that PFKFB4 reprogramed glucose metabolism and promoted cell stemness by enhancing glycolysis. Strikingly, diminishing PFKFB4 levels improved drug sensitivity and overcame chemoresistance during palbociclib treatment in ER+ BC. Conclusions: These findings not only demonstrated the novel mechanism underlying which ER+ BC cells resisted to palbociclib, but also provided a possible therapeutic strategy in the intervention of ER+ BC to overcome drug resistance. [ABSTRACT FROM AUTHOR]

Multibody musculoskeletal modeling of human gait has been proved helpful in investigating the pathology of musculoskeletal disorders. However, conventional inverse dynamics methods rely on external force sensors and cannot capture the nonlinear muscle behaviors. Meanwhile, the forward dynamics approach is computationally demanding and only suited for relatively simple tasks. This study proposed an integrated simulation methodology to fulfill the requirements of estimating foot-ground reaction force, tendon elasticity, and muscle recruitment optimization. A hybrid motion capture system, which combines the marker-based infrared device and markerless tracking through deep convolutional neural networks, was developed to track lower limb movements. The foot-ground reaction forces were determined by a contact model for soft materials, and its parameters were estimated using a two-step optimization method. The muscle recruitment problem was first resolved via a static optimization algorithm, and the obtained muscle activations were used as initial values for further simulation. A torque tracking procedure was then performed by minimizing the errors of joint torques calculated by musculotendon equilibrium equations and inverse dynamics. The proposed approach was validated against the electromyography measurements of a healthy subject during gait. The simulation framework provides a robust way of predicting joint torques, musculotendon forces, and muscle activations, which can be beneficial for understanding the biomechanics of normal and pathological gait. [ABSTRACT FROM AUTHOR]

Relaxation mechanisms of shake gels (particle-polymer systems) are not yet fully understood, mainly because of the lack of effective structural parameters to describe relaxation processes. Small-angle X-ray scattering and dynamic light scattering methods were employed to track the relaxation processes in a water-based shake gel system, composed of 20 wt % of 24.8 nm silica nanoparticles and 0.3 wt % of poly(ethylene oxide) (PEO 1000k). The gelation of the studied silica-PEO dispersion was readily induced by quick manual shaking (∼3 cycles/s). Temporal structural evolution of the shake gel after manual agitation was inferred from the development of the modeled parameters. The quantitative structural parameters extracted from the scattering data, i.e. nearest neighbor distance of silica nanoparticles and floc size of gel network, showed that the shake gel network quickly relaxes during the first 10–20 min following the shake-induced gelation, and then slowly reaches a quiescent structure after 1 h. • Temporal structural evolution of the silica-PEO shake gel immediately after shaking was characterized by X-ray and light scattering. • The relaxation behavior was depicted by the quantitative relaxation parameters — nearest neighbor distance of silica particles and floc size of gel network. • The studied shake gel network quickly relaxed during the first 10–20 min but slowly thereafter. • This work advanced the deep understanding of fundamental relaxation processes of shake gels at nanometric resolution. [ABSTRACT FROM AUTHOR]

Abstract: A computational approach is proposed for the dynamic analysis of complicated membrane systems, such as parachutes and solar sails, which undergo overall motions, large deformations, as well as wrinkles owing to the small membrane resistance to the compressive stress therein. Based on previous studies, a thin shell element of gradient deficient Absolute Nodal Coordinate Formulation (ANCF) is proposed first. Then, the strain energy of the above shell element is derived by using the definition of the Green–Lagrange strain tensor in continuum mechanics. The computationally efficient formulations of elastic forces and their Jacobian for the above shell element are also derived via the skills of tensor analysis. Afterwards, a membrane element of ANCF is proposed by integrating the criterion of wrinkle/slack into the above shell element. To deal with the small compressive stiffness for the membrane element, the Stiffness Reduction Model (SRM) is introduced to the membrane elements. Finally, four case studies including both statics and dynamics of different membrane systems are given to validate the proposed approach. The final example of the spinning deployment of a solar sail shows the efficacy of the proposed approach in the dynamic analysis of complicated membrane system undergoing an overall motion, large deformations and wrinkles. [Copyright &y& Elsevier]

The spinning solar sail of large scale has been well developed in recent years. Such a solar sail can be considered as a rigid-flexible multibody system mainly composed of a spinning central rigid hub, a number of flexible thin tethers, sail membranes, and tip masses. A simplified interplanetary kite-craft accelerated by radiation of the Sun (IKAROS) model is established in this study by using the absolute-coordinate-based (ACB) method that combines the natural coordinate formulation (NCF) describing the central rigid hub and the absolute nodal coordinate formulation (ANCF) describing flexible parts. The initial configuration of the system in the second-stage deployment is determined through both dynamic and static analyses. The huge set of stiff equations of system dynamics is solved by using the generalized-alpha method, and thus the deployment dynamics of the system can be well understood. [ABSTRACT FROM AUTHOR]

Abstract: A new methodology is proposed for the dynamic analysis of rigid-flexible multibody systems with ElastoHydroDynamic (EHD) lubricated cylindrical joints. The EHD lubricated cylindrical joint is formulated by the Natural Coordinate Formulation (NCF) and the 20-node hexahedral elements of Absolute Nodal Coordinate Formulation (ANCF), with the lubricant pressure determined through the resolution of the Reynolds’ equation employing the finite difference method. The main outcomes are validated with those obtained by using the commercial software ADINA. It is shown that the bearing flexibility plays a significant role in the system responses, extends the lubricant distribution space and, consequently, reduces the lubricant pressure. [Copyright &y& Elsevier]

Abstract: The dynamics and control of a rigid-flexible multibody system with multiple cylindrical clearance joints are studied via the Absolute Coordinate Based (ACB) method that combines the Natural Coordinate Formulation (NCF) describing rigid bodies and the Absolute Nodal Coordinate Formulation (ANCF) describing flexible bodies. The spatial cylindrical joints with clearances are modeled by two rigid bodies, that is, the journal and bearing, where the difference in radius and axial directions defines the radial clearance and axial clearance, respectively. A new four-point contact kinematic model of NCF is proposed for the rigid cylindrical clearance joint. A combined control scheme consisting of a feedforward torque and a PID feedback controller is adopted to track the joint trajectories. Based on the principle of virtual work, a new and simple method is proposed to evaluate the feedforward torque. To improve computational efficiency, an OpenMP based parallel computational strategy is used to solve the large scale equations of motion. Three examples are given to verify the effectiveness of the proposed formulations and demonstrate the complex dynamics of rigid-flexible multibody systems with multiple cylindrical clearance joints. [Copyright &y& Elsevier]

Abstract: This paper reports morphology-tuned synthesis of arrayed one-dimensional ZnO nanostructures on Ag-coated glass substrates from Zn(NO3)2 and dimethylamine borane (DMAB) aqueous solutions and their photoluminescence and photocatalytic properties. By adjusting the Zn(NO3)2 concentration in the solutions, the ZnO nanoneedle arrays, nanorod arrays, and polycrystal films can be obtained. Low Zn(NO3)2 concentrations result in ZnO nanoneedle arrays. The ZnO nanoneedles grow along the 〈0001〉 directions. The growth process of the ZnO nanoneedles at low Zn(NO3)2 concentrations goes through the formation of the equiaxial ZnO granules, the growth of the equiaxial granules into small nanorods, the growth of the small nanorods into nanoneedles, the growth of the nanoneedles in diameter and length, the growth of the nanoneedles into nano-obelisks, and the growth of the nano-obelisks into thick hexangular rods. So the morphologies of the arrayed 1D ZnO nanostructures can be tuned from arrayed nanoneedles through arrayed nanorods and nano-obelisks to arrayed thick hexagonal rods by controlling the Zn(NO3)2 concentration in the DMAB and Zn(NO3)2 solutions and/or the deposition time in our process. The ZnO nanoneedle arrays have the largest ratio of the visible to ultraviolet emission and the highest photocatalytic activity. [Copyright &y& Elsevier]

Polyethylene glycol 400 (PEG 400) has been demonstrated as an efficient and eco-friendly reaction medium for the preparation of organic azides from structurally diverse halides by nucleophilic substitution reaction with NaN3 under mild conditions. The advantages of this protocol are: operational simplicity, environmental safety, broad substrate scope, excellent functional group tolerance, and short reaction time. The PEG 400 can be recovered and reused. [ABSTRACT FROM AUTHOR]

The irradiance of an elliptic Gaussian beam that is high enough to excite high-order nonlinear refraction effect is used to calculate the normalized on-axis transmittance function in the z-scan technique by introducing complex beam parameters which make the calculation simpler. The transmittance formula is applied to the first-, first two-, and first three-order nonlinearities. Numerical evaluation shows that the symmetry no longer holds when using an elliptic Gaussian beam instead of a circular Gaussian beam. A distortion is observed in the central part of the curve, which decreases as ellipticity increases. Moreover, the variation of the normalized peak-valley difference decreases as ellipticity decreases. [ABSTRACT FROM AUTHOR]