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This study presents a novel and straightforward model of a nanomotor capable of rotation propelled by friction at the solid-liquid interface. Within this nanosystem operating in a Rotary Electric Field (REF), a pristine carbon nanotube, electrically neutral, is infused with water, serving as the rotor. Polar molecules within the water rotate alongside the REF, generating interface friction that propels the nanotube rotor. Molecular dynamics simulations demonstrate that the nanomotor rapidly achieves a stable rotational frequency (SRF), typically within 200 ps in this investigation. Furthermore, each rotor tube possesses a maximum SRF value, denoted as ωRMax. When the REF frequency (ωE) exceeds ωRMax, the rotor tube, water cluster, and REF exhibit varying rotational frequencies. It is also observed that the relationship between the rotor's SRF and ωE conforms to an inverse square law when ωE surpasses ωRMax. The underlying mechanism is elucidated. These findings can inform the design of a rotary nanomotor constructed from water-filled carbon nanotubes, offering tunable SRF capabilities.

In order to break through the top-down combustion mode brought by the traditional pillars, it is explored to explore the exploration of delay composition array construction in two-dimensional dimensions. In this study, B-CuO, B-Bi2O3, B-Fe2O3sticks and combustion networks with good forming properties were prepared with the help of a micro-pen direct ink writing device by dispersing the above materials in DMF with boron and metal oxides as the main body of the charge and F2602as the binder. The sticks were thermally ignited using a nichrome wire, and the flame propagation behaviors of the sticks with different formulations, spacings and heights were tracked with a high-speed camera, and a series of combustion networks were designed on the premise of not leaping into flames. Results show that the B-CuO stick has the fastest ignition speed level (19.71–29.02 mm ·s−1) at equivalence ratios of 1.0–4.0, followed by B-Bi2O3(5.99–16.01 mm ·s−1) and B-Fe2O3is the slowest (1.91–4.94 mm ·s−1). The sticks burned best at an equivalence ratio of 1.0–1.5. A variety of combustion networks were constructed on 50 × 50 mm glass slides by selecting B-CuO, B-Bi2O3, and B-Fe2O3at the equivalence ratios of 1.0, 1.5, and 1.5, respectively, among which B-CuO had the shortest combustion time (5.17 s), the shortest total combustion network length (252 mm), and 400 mm network could be realized for B-Bi2O3. Construction and 19.85 s, and B-Fe2O3can realize 608 mm network length and 130.7 s combustion time. Through these studies, the two-dimensional combustion network construction of boron-metal oxides was realized, which provides a new idea for the delay action in small size.

Researching subcooled flow boiling behaviors is critical for achieving efficient heat exchange in engineering processes involving heat generation. This study endeavors to apply a wall boiling model within the Euler–Lagrange framework to evaluate the nonuniform dynamics of subcooled flow boiling in the vertically oriented channels. The simulated dynamics are observed to well reproduce the experimentally captured data. The computed results revealed that boiling can facilitate maintaining a uniform wall temperature distribution and mitigate wall temperature rising owing to the reduced convective heat flux components, which are linked to an increase in bubble influence area radio. The heating wall can be divided into two or three regions under varying wall heat fluxes. The improved heat exchange performance in each region is related to the enhanced fluid turbulence and/or bubble influence area. Additionally, the linear enlargement of bubble size along the channel is prompted by a shift toward larger bubbles and a decrease in small ones. This work may offer meaningful simulation strategies and novel perspectives for subcooled flow boiling.

The electrochemical reduction of nitrate can be a promising and sustainable alternative for the industrially used, energy-intensive Haber–Bosch process under mild conditions and also solve the issue of nitrate nitrogen pollution in water. We present here the facile construction of an N-doped CuO@Co3O4/NF nanoarray on nickel foam for highly efficient NH3electrosynthesis viaselective NO3−reduction in neutral electrolyte. At −0.85 V (versusthe reversible hydrogen electrode (RHE)), this N-doped CuO@Co3O4/NF nanoarray obtained an outstanding Faraday efficiency (FE) of 99.78% and NH3yield of up to 31.92 mg h−1cm−2when operated in 0.1 M phosphate buffer solution with added 50 mM NaNO3. In addition, its excellent electrochemical performance was maintained for at least 12 h. Furthermore, according to the characterization, the enhanced electrocatalytic performance could be attributed to the synergistic effect of N-dopant and relatively large amounts of Co(ii) and oxygen vacancies (OVs) in the heterostructure, leading to the suppression of the hydrogen evolution reaction (HER) and the improvement of electron/mass transfer at the N-doped CuO@Co3O4/NF heterostructure.

Phubbing refers to the act of engaging with a phone while ignoring others during interaction. When phubbing behaviors occur in the context of parent-child communication, it is defined as parental phubbing. Prior research indicated that parental phubbing positively predicted adolescents’ depressive symptoms. However, no meta-analysis has been conducted to investigate the association between parental phubbing and adolescents’ depressive symptoms and what factors moderated this association. After a systematic search for articles published before July 2023, 15 articles analyzing 22,478 participants were obtained in the meta-analysis. Specifically, the study sample sizes ranged from 293 to 4213, with a mean age of 14.460 years and an average proportion of female participants of 0.510. In addition, most of the samples were from middle and high schools, except for one study in the United States; all included studies were conducted in China. The random effects model was used to get reliable estimates of effect sizes and to examine a range of moderators. Results revealed a significant positive association (r=0.310), and this relationship was generally consistent across different moderating factors (i.e., gender, residency of birth, school year, measurements of parental phubbing or depressive symptoms, and the conception of phubbing). Consequently, the findings supported the detrimental effects of parental phubbing on adolescent mental health.

In this study, we developed a simple and sensitive colorimetric sensing method for the detection of UO22+, which was built to release MB from the molybdenum disulfide with a phosphate group (MoS2-PO4) gated mesoporous silica nanoparticles functionalized phosphate group (MSN-PO4) with UO22+chelating. In the presence of UO22+, MoS2-PO4can be effectively adsorbed onto the surface of MSN-PO4based on the coordination chemistry for strong affinity between the P–O bond and UO22+. The adsorbed MoS2-PO4was then utilized as an ideal gate material to control the release of signal molecules (MB) entrapped within the pores of MSN-PO4, resulting in a detectable decrease in the absorption peak at 663 nm. This colorimetric sensing demonstrated the advantages of simplicity and easy manipulation and exhibited a linear response to the concentration of UO22+within the range of 0.02–0.2 μM. The detection limit of UO22+was determined to be 0.85 nM, which was lower than the limit (130 nmol L−1) set by the US Environmental Protection Agency. Furthermore, the proposed colorimetric sensing method has been utilized to determine UO22+in samples of Xiangjiang River and tap water, and a high recovery rate was achieved. This method shows promising potential in preventing and controlling environmental pollution.

Mercury is a highly toxic element that is widely present in all types of environmental media and can accumulate in living organisms. Prolonged exposure to high levels of mercury can lead to brain damage and death, so the detection of mercury is of great importance. In this study, a cost-effective and easy-to-operate electrochemical sensing method was successfully developed based on an amino-functionalized titanium-based MXene (NH2–Ti3C2Tx) for the rapid and selective detection of Hg2+that could have a coordination effect with the –NH2group of NH2–Ti3C2Txto promote the efficient accumulation of Hg2+. In this strategy, the NH2–Ti3C2Txwas first modified on glassy carbon electrodes (GCE) to fabricate the electrochemical sensor. Benefiting from the excellent electrical conductivity, abundant active sites, and strong adsorption capacity performance of the NH2–Ti3C2Tx, the NH2–Ti3C2Txmodified GCE (NH2–Ti3C2Tx/GCE) exhibited satisfactory selectivity and enhanced square wave anodic stripping voltammetry (SWASV) measurement for the rapid detection of trace amounts of Hg2+in aqueous solutions. The electrochemical sensor was found to be capable of detecting Hg2+with a low detection limit of 8.27 nmol L−1and a linear range of 0.5 μmol L−1to 50 μmol L−1. The response time of the electrochemical sensing method was 308 s. In addition, the electrochemical sensing method has good selectivity, repeatability and stability, and multiple heavy metal ions have no effect on its detection, with repeatability and stability RSDs of 1.68% and 1.43%, respectively. Furthermore, the analysis of practical water samples demonstrated that the developed method was highly practical for the actual determination of Hg2+with recoveries in the range of 99.22–101.90%.

Emotional distress (ED), commonly characterized by symptoms of depression and/or anxiety, is prevalent in patients with cancer. Preclinical studies suggest that ED can impair antitumor immune responses, but few clinical studies have explored its relationship with response to immune checkpoint inhibitors (ICIs). Here we report results from cohort 1 of the prospective observational STRESS-LUNG study, which investigated the association between ED and clinical efficacy of first-line treatment of ICIs in patients with advanced non-small-cell lung cancer. ED was assessed by Patient Health Questionnaire-9 and Generalized Anxiety Disorder 7-item scale. The study included 227 patients with 111 (48.9%) exhibiting ED who presented depression (Patient Health Questionnaire-9 score ≥5) and/or anxiety (Generalized Anxiety Disorder 7-item score ≥5) symptoms at baseline. On the primary endpoint analysis, patients with baseline ED exhibited a significantly shorter median progression-free survival compared with those without ED (7.9 months versus 15.5 months, hazard ratio 1.73, 95% confidence interval 1.23 to 2.43, P= 0.002). On the secondary endpoint analysis, ED was associated with lower objective response rate (46.8% versus 62.1%, odds ratio 0.54, P= 0.022), reduced 2-year overall survival rate of 46.5% versus 64.9% (hazard ratio for death 1.82, 95% confidence interval 1.12 to 2.97, P= 0.016) and detriments in quality of life. The exploratory analysis indicated that the ED group showed elevated blood cortisol levels, which was associated with adverse survival outcomes. This study suggests that there is an association between ED and worse clinical outcomes in patients with advanced non-small-cell lung cancer treated with ICIs, highlighting the potential significance of addressing ED in cancer management. ClinicalTrials.gov registration: NCT05477979.

Speckle noise is a main obstacle for change detection tasks of synthetic aperture radar (SAR) images. However, change detection methods often focus on removing noise and ignore the importance of preserving details of SAR images, which results in a loss of classification accuracy. In order to alleviate the contradiction between removing noise and preserving details, a multi-objective change detection method based on a modified Gaussian mixture model (GMM) is proposed in our paper. In the framework of our multi-objective model, one objective is composed of an special GMM of being applied to distinguish changed and unchanged regions and preserve details. The another is a carefully crafted noise reduction operator for removing speckle noise, which is constructed as a penalty to refine the result of classification. The aforementioned conflicting objectives are optimized simultaneously, which is conducted by a common multi-objective evolutionary algorithm based on decomposition (MOEA/D). Then, a series of solutions are obtained, all of which represent a balance of detail preservation and noise reduction. Compared with three classical change detection methods, the proposed method is applied to four real datasets in experimental studies. Experimental results and theoretical analysis reveal its effectiveness.

Preeclampsia (PE) is a multisystemic and placental inflammatory disease that causes maternal and infant health issues. As one of the active components in peony root extract, paeonol (Pae) exerts anti‐apoptosis and anti‐inflammatory effects. Nonetheless, the protective role of Pae in PE has not yet been characterized. A mouse model of PE was constructed through tail vein injection of 1 mg/d phosphatidylserine/dioleoyl‐phosphatidycholine suspension. The levels of inflammatory cytokines in the placenta were examined via enzyme‐linked immunosorbent assay (ELISA). The mRNA levels of inflammatory cytokines (TNF‐α, IL‐6, IFN‐γ, and IL‐4) and apoptosis markers (Bax, Bcl‐2, and caspase‐3) were tested using quantitative reverse transcription‐polymerase chain reaction (qRT–PCR). Western blot analysis was performed to detect the protein levels of apoptosis markers and Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway‐related molecules. Here, Pae repressed the inflammatory response in the placenta of PE‐like mouse models, as demonstrated by the decreased concentrations and mRNA levels of TNF‐α, IL‐6, and IFN‐γ and the increased concentrations and mRNA levels of IL‐4. Apoptosis in the placentas of PE‐like mouse models was attenuated by Pae, as manifested by the downregulated mRNA and protein levels of Bax and cleaved‐caspase‐3 and the upregulated Bcl‐2. Administration of Pae inhibited the phosphorylation of JAK2 and STAT3 in the placental tissues of PE mice. The JAK2/STAT3 pathway agonist (SC‐39100) reversed Pae treatment‐mediated suppression of placental inflammation and apoptosis in PE mice. Overall, Pae inhibits the JAK2/STAT3 signaling pathway to attenuate placental inflammation and apoptosis in PE mice.

It is widely known that an optimal nucleotide sequence context immediately upstream of the AUG start codon greatly improves the efficiency of translation initiation of mRNA in mammalian and plant somatic cells, which in turn increases protein levels. However, it is still unclear whether a similar regulatory mechanism is also present in highly differentiated cells. Here, we surveyed this issue in Arabidopsis thalianasperm cells and found that the sequence context-mediated regulation of translation initiation in sperm cells is generally similar to that in somatic cells. A simple motif of four adenine nucleotides at positions − 1 to − 4 greatly improved the efficiency of translation initiation, and when the motif was present there, translation was even initiated at some non-AUG codons in sperm cells. However, unlike that in mammalian cells, a mainly effective nucleotide site to regulate the efficiency of translation initiation was not present at positions − 1 to − 4 in sperm cells. Meanwhile, different from somatic cells, sperm cells did not use eukaryotic translation initiation factor 1 to regulate the efficiency in a poor context consisting of the lowest frequency nucleotides. All these results contribute to our understanding of the cytoplasmic event of translation initiation in highly differentiated sperm cells.

The shape of the earth's aurora serves as a direct monitor of important physical processes in the magnetosphere. Detecting auroral regions is therefore a crucial step in studying auroral activity in the field of space physics. Since auroral ovals are captured as images under undesirable conditions of low illumination, intensity distributions overlapping between auroral oval regions and the background present challenges for auroral oval segmentation methods. Granular computing, including fuzzy sets and rough sets, is an appropriate choice to better handle the uncertainty inherent in observed images. In this paper, we present a novel active contour model unaffected by intensity inhomogeneity for detecting auroral ovals in satellite imagery. By integrating the principles of fuzzy sets and rough sets, we develop a technique to automatically detect class boundaries. The resulting characterization leads to an efficient description of uncertain regions near auroral oval boundaries, as well as uncertainty in class boundaries. The approach by which an image is approximated by regions with piecewise-constant intensities within different local regions is more suitable for auroral images with intensity inhomogeneity. Considering local image information, we therefore use spatially varied thresholding for each pixel rather than constant thresholding. As a result, our proposed method can effectively and efficiently segment auroral ovals whose boundaries are not easily separated from the background. Further, experimental results on auroral oval images demonstrate the effectiveness of our proposed method in terms of human visual perception and segmentation accuracy. [ABSTRACT FROM AUTHOR]

The molecular underpinnings of pediatric asthma present avenues for targeted therapies. A deeper exploration into the significance of differentially expressed autophagy-related genes (DE-ARGs) and their interactions with the long noncoding RNA (lncRNA)–microRNA (miRNA)–mRNA network may offer insights into the pathogenesis of pediatric asthma. DE-ARGs were retrieved from the Gene Expression Omnibus and the Human Autophagy Database. These DE-ARGs were subjected to comprehensive analyses, including Gene Ontology, Kyoto Encyclopedia of Genes and Genomes pathway, Gene Set Enrichment Analysis, and protein–protein interaction networks. The identified DE-ARGs were further verified for core gene expression. The miRDB and ENCORI databases were used for inverse miRNA predictions. Furthermore, miRNA–lncRNA interactions were predicted using LncBase and ENCORI platforms. Following the exclusion of lncRNAs exclusively localized in the nucleus and extracellular space, a competitive endogenous RNA (ceRNA) network was established and subsequently subjected to detailed analysis. The mRNA expression patterns in the ceRNA network were validated using quantitative real-time PCR. In total, 31 DE-ARGs were obtained, of which 29 were up-regulated and 2 were down-regulated. Notably, the autophagy, regulation of apoptotic signaling pathways, interferon-α/β signaling, interferon γ signaling, autophagy-animal, and apoptosis pathways were predominantly enriched in pediatric asthma. Five hub genes (VEGFA, CFLAR, RELA, FAS, and ATF6) were further analyzed using the Gene Expression Omnibus dataset to verify their expression patterns and diagnostic efficacy. Four hub genes (VEGFA, CFLAR, RELA, and FAS) were obtained. Finally, a ceRNA network of 4 mRNAs (VEGFA, CFLAR, RELA, and FAS), 3 miRNAs (hsa-miR-320b, hsa-miR-22-3p, and hsa-miR-625-5p), and 35 lncRNAs was constructed by integrating data from literature review and analyzing the predicted miRNAs and lncRNAs. Moreover, the quantitative real-time PCR data revealed a pronounced upregulation of Fas cell surface death receptor. The identification of 4 DE-ARGs, especially Fas cell surface death receptor, has shed light on their potential pivotal role in the pathogenesis of pediatric asthma. The established ceRNA network provides novel insights into the autophagy mechanism in asthma and suggests promising avenues for the development of potential therapeutic strategies.

To explore the precise mechanism of electroacupuncture (EA) to delay cognitive impairment in Alzheimer disease. N-Acetylaspartate (NAA), glutamate (Glu) and myoinositol (mI) metabolism were measured by magnetic resonance spectroscopy, learning and memory of APP/PS1 mouse was evaluated by the Morris water maze test and the step-down avoidance test, neuron survival number and neuronal structure in the hippocampus were observed by Nissl staining, and BDNF and phosphorylated TrkB detected by Western blot. EA at DU20 acupuncture significantly improve learning and memory in behavioral tests, up-regulate NAA, Glu and mI metabolism, increase the surviving neurons in hippocampus, and promote the expression of BDNF and TrkB in the APP/PS1 transgenic mice. These findings suggested that EA is a potential therapeutic for ameliorate cognitive dysfunction, and it might be due to EA could improve NAA and Glu metabolism by upregulation of BDNF in APP/PS1 mice.

Abstract Low rank and sparse matrix decomposition is increasingly concerned in many research fields for its particular properties in exploring local and global components. The objective of this problem consists of two conflicting terms, the low rank term and the sparse term, most of the previous methods combine these two terms into a scalar objective with weight parameter. However, the preset of weight parameter is a difficult task because any priori knowledge about two terms is unavailable before optimization. In this paper, we establish a singular value encoding based multi-objective low rank and sparse matrix decomposition model. Two conflicting objectives are constructed to find the low rank and sparse components of the given data matrix. A novel multi-objective memetic algorithm, which encodes the singular value of the low rank matrix, is proposed to minimize two objectives simultaneously. The proposed method can obtain a series of different trade-off solutions between low rank and sparse components, and decision makers can choose satisfying solution from them directly. The experimental results demonstrate that the proposed method is effective and has better performance than some existing approaches in terms of the decomposition accuracy and the diversity of solutions. [ABSTRACT FROM AUTHOR]

Molybdenum dioxide (MoO2) has attracted many interests due to its unique properties and potential applications. Here, we report the synthesis of high quality MoO2@MoS2nanorods on c-sapphire substrates through an atmospheric pressure chemical vapor deposition (APCVD) approach. Optical microscopy (OM), cross-sectional scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), and (grazing incidence) X-ray diffraction ((GI)XRD) measurements reveal that these MoO2nanorods exhibit epitaxial growth behaviors on c-sapphire substrates with the orientation relationship of MoO2(100)∥sapphire(0001) and MoO2⟨001⟩ aligned well with sapphire ⟨101̅0⟩. Raman spectroscopy/imaging, energy dispersive spectroscopy (EDS), and GIXRD results disclose that such MoO2nanorods are wrapped by MoS2(MoO2@MoS2). Devices based on transferred individual MoO2@MoS2nanorods show a resistivity of ∼1.65 × 10–4Ω·cm, comfirming that such nanorods possess higher crystalline degree. Our findings will be helpful for the applications of MoO2@MoS2in the fields of nanoelectronic devices.

By fixing of the outer tube of double-walled carbon nanotubes, a thermally driven rotary nanomotor can be obtained one or more carbon atoms at the end of the stator have an obvious inward radial deviation. Due to the asymmetry of the potential field of the stator, a collision between two tubes leads to the axial component of angular momentum that drives the rotation of the rotor. Relative sliding between the two tubes is resisted due to the roughness of the potential field of stators. Hence, the rotational frequency of the rotor has a maximal value in the balanced state. The spectrum of rotational frequency with respect to temperatures from 8 to 2000 K is presented by means of molecular dynamics simulation. The temperature interval is divided into five zones on the basis of the characteristics of the spectrum. In the robust zone, the nanomotor exhibits stationary rotation. In the controllable zone, the rotational frequency of rotor can be adjusted by varying the temperature. In particular, if a rotating rotor is cooled to an ultralow temperature, the final stable value of the rotational frequency is still very high and is slightly lower than the maximal value rather than zero; i.e., the nanomotor will theoretically never stop rotating.

Nanotube synthesizing from black phosphorus (BP) is still challenging in laboratory. Fabricating a BP nanotube by self-assembling of a BP nanoribbon seems promising. To estimate the feasibility of such fabrication method, this study performs numerical experiments of self-assembling a jammed BP ribbon on a fixed carbon nanotube using molecular dynamics simulation. The study is based on the following two facts: The phosphorus–phosphorus (P–P) bond is weaker than the bond of carbon–carbon (C–C) and the van der Waals interaction among nonbonding phosphorus atoms is stronger than that between phosphorus atoms and carbon atoms. The results show that when a longer BP ribbon is jammed by a shorter BP ribbon the self-assembling result depends on the relative positions of carbon nanotube (CNT) and the two BP ribbons. Only when the shorter BP ribbon is on the outside of the longer ribbon can the longer BP ribbon be wound on the CNT to form an ideal BP nanotube. The finding is helpful for practical applications of BP nanotubes in nanodevices.

AbstractIn traditional uniaxial compression test, the friction between specimen and bearing plates during testing leads to non-uniform deformation of the specimen. Therefore, the compressive properties of a material may not be accurately measured. To improve the accuracy of measurement, a comprehensive testing scheme is developed in this report. In our method, both close range photogrammetry (CRP) and numerical inversion of the specimen deformation are introduced into a traditional compression test. Firstly, the surface deformation of a specimen during the testing is captured by CRP technique and measured using software Ncorr. Secondly, the mechanical properties of a material can be calculated using testing data. Thirdly, the numerical deformation of specimen under the same loads as those in testing is obtained by finite element method. There is a difference between the testing and numerical results. Minimizing the difference will provide optimal material properties. Finally, an inversion model is built, in which the mechanical properties are design variables. The objective is to minimize the difference between the testing deformation and numerical deformation. The consultant reaction along compression direction on a contact surface of specimen acts as a constraint function. Inversion results show that both the elastic modulus and Poisson’s ratio are modified.

In this paper, we present an adaptive coevolutionary memetic algorithm (ACMA) for examination timetabling problems. In our proposed algorithm, the evolutionary search is conducted in two spaces: the heuristic space and the solution space. In the heuristic space, a hyper-heuristic approach is utilised to generate the initial population, and then basic evolutionary operators are used to find the potential heuristic lists. The evolutionary strategy in the heuristic space is regarded as a global search procedure. In the solution space, according to the solution structure, some specific evolutionary operators are designed for expanding the scope of search in solution space. This scheme can be viewed as the local search procedure. By combining two different strategies, the cooperation between them will eventually increase the diversities in the population. In order to determine which space should be selected at each generation, an adaptive parameter is designed based on the proportion of feasible solutions in the current population. Experimental results demonstrated that ACMA obtains competitive results and outperforms the compared approaches on some benchmark instances.

Phase change is a phenomenon that has been extensively utilized in chemical engineering, energy, electronics, vehicle, and space exploration. From both the science and engineering perspectives, gaining a profound understanding of the intricacies of multiphase flow processes accompanied by heat and mass transfer due to phase change is of fundamental importance. Indeed, the computational fluid dynamics (CFD) has been increasingly applied as an effective tool to give an in-depth and efficient analysis of the phase change processes, thereby enhancing our understanding and capacity to control and optimize the phase change effects in these processes. This paper seeks to provide a comprehensive review of the utilization of CFD methodologies in the simulations of phase change flows across various applications, including temperature management, drying, separation and purification, and others. First, the CFD models at various scales that are developed to elucidate the phase change processes are summarized. Second, the noteworthy advances in the recent CFD simulation work on various phase change processes are presented, respectively. Finally, the challenges and potential prospects to facilitate the application of the phase change flow are discussed. The current review aims to offer insightful guidance for the CFD modeling of phase change processes in numerous engineering application scenarios.

Barium ferrite micro/nanofibers were successfully prepared via the electrospinning by using dimethyl formamide (DMF) as the solvent, poly vinyl pyrrolidone (PVP) as the spinning auxiliaries and iron nitrate and barium nitrate as raw materials. The effect of poly vinyl pyrrolidone on the structure, morphology, magnetic and microwave absorbing properties were investigated by scanning electron microscope (SEM), X-ray diffraction analysis (XRD), vibration sample magnetometer (VSM) and vector network analyzer (VNA). XRD patterns of the samples confirmed that when the additive content of PVP was up to 10%, (wt%) pure barium ferrite fibers formed under the condition of the same heat treatment. Also, the FE-SEM images showed that the morphology of the fibers improved with the increase of PVP content. Moreover, the VSM results demonstrated that the saturation magnetization can reach 54.7 emu/g when the PVP dosage is 14% (wt%) in the precursor solution.

Silver nanowires–epoxy composites were prepared via cryomilling dispersion and hot-press forming process. The microstructure of the silver nanowires was studied by SEM. Dependence of dielectric properties of the composites on volume fraction of silver nanowires and frequency was investigated RF impedance material analyzer. The percolation threshold of the composites was 0.16, the value of the dielectric constant of the composite was as high as 100.

In studying the rotational transmission behavior of a carbon nanotube-based bearing (e.g., (5, 5)/(10, 10)) driven by a CNT motor (e.g., (9, 9)) at finite temperature, one can find that the rotor has different dynamic states from the motor at different environmental condition. In particular, the rotor can be in the overspeeding rotational transmission (ORT) state, in which the rotational speed of the rotor is higher than that of the motor. If we change the rotational frequency of the motor (e.g., >100 GHz) and the curved angle of the rotor, the bearing can reach the ORT state. Besides, in the ORT state, the ratio of the rotor’s rotational speed over that of the motor will be not higher than the ratio of the motor’s radius over that of the rotor. There are two major reasons that result in the bearing to the ORT state. One is that the thermal vibration of atoms between the carbon–hydrogen (C–H) end of the motor and that of the rotor has a drastic collision when the motor is in a high rotational speed. The collision causes the atoms at the end of the rotor to have a circular and axial velocity. The circular velocity leads to the rotation of the rotor and the axial velocity causes the oscillation of the rotor. Another reason is sourced from the oblique angle between the rotor and the stators due to the rotor having a curved angle. A higher oblique angle results in higher friction between the rotor and stator, and it also provides higher collision between the rotor and motor. Hence, one can adjust the transmission state of the rotor by changing not only the environmental temperature but also the rotational speed of the motor, as well as the curved angle of the rotor. The mechanism is essential in guiding a design of a rotational transmission nanodevice which transforms the rotation of the motor into other states of the rotor as output signals.

Composite patch adhesively bonded repair is an advanced repairing method for damaged metallic structure, and patch designing is important before repairing, which decides final repairing effect. Based on 3D FEM, the model of aluminum plate with a central through crack adhesively bonded repaired with composite patch was established, which can take into account residual thermal stress and bending deformation caused by differences of thermal expansion coefficient. SIF was calculated using virtual crack closure technology and compared to evaluate patch designing. The results show that for through centrally cracked aluminum plate, rectangle boron/epoxy patch is the best, and more plies whose fiber direction is parallel to loading direction are, better repairing can be got.

This research aimed at studying the quantitative relationship between chlorophyll content, LAI, yield and spectral parameters of two species of winter wheat (Yangmai 13 and Xumai 31) with Free Air Temperature Increased facility. Four warming scenarios were designed in the experiment: all-day warming (AW, warming of 1.9°C, daytime warming (DW,6:00am-18:00pm,warming of 2.1°C), nighttime warming (NW,18:00 pm-6:00 am next day, warming of 1.7°C) and the control (CK, without warming). The results showed that reflectance of the four treatments at near infrared flat (nm-nm) had significant differences in booting stage and the sequence was: DW>AW>CK>NW. At visible band, the reflectance under NW treatment was much lower than that under other treatments. PND920 and P_Area920 were correlated with chlorophyll with high coefficient of determination. RVI and NDVI which constituted by the 810nm and 560nm reflectance were highly correlated with LAI. Booting stage was the optimum period for yield estimation. P_Depth560, NDVI (560,450) and RVI (560,450) were significantly related to yield and thus they could be utilized for yield prediction.

In this paper, a method is proposed using the motion vector in Gabor space to recognize smoke region. Smoke orbit is described as up-forward and has some similar sharp in feature space. The propose method is assessed by calculating 45,90,135 degree upward vectors , and determined the possibility of smoke region. Different images were tested using smoke video scenes, and it meets the desired expectation. The next step will be in-depth study represents a high-dimensional space .

Invasion and metastasis are the major cause of deaths in patients with esophageal cancer. In this study, we isolated cancer stem-like cells from an esophageal squamous cell carcinoma cell line EC109 based on aldehyde dehydrogenase 1A1 (ALDH1A1), and found that ALDH1A1highcells possessed the capacities of self-renewal, differentiation and tumor initiation, indications of stem cell properties. To support their stemness, ALDH1A1highcells exhibited increased potential of invasion and metastasis as compared with ALDH1A1lowcells. ALDH1A1highesophageal squamous cell carcinoma cells expressed increased levels of mRNA for vimentin, matrix metalloproteinase 2, 7 and 9 (MMP2, MMP7 and MMP9), but decreased the level of E-cadherin mRNA, suggesting that epithelial–mesenchymal transition and secretary MMPs may be attributed to the high invasive and metastatic capabilities of ALDH1A1highcells. Furthermore, we examined esophageal squamous cell carcinoma specimens from 165 patients and found that ALDH1A1highcells were associated with esophageal squamous dysplasia and the grades, differentiation and invasion depth, lymph node metastasis and UICC stage of esophageal squamous cell carcinoma, as well as poor prognosis of patients. Our results provide the strong evidence that ALDH1A1highcancer stem-like cells contribute to the invasion, metastasis and poor outcome of human esophageal squamous cell carcinoma.

The geometric shape and internal forces were monitored during the construction of the hypostatic framework structure which is a composite system of steel beam and arch. The displace settlement was measured for the control of the geometric shape. And nine vibrating wire strain gauges were embedded on the key sections for the real time control of internal force. In order to cancel out the interference of the temperature variation effectively, displace settlement and internal forces were monitored around the clock at different time points. Then the measured values were compared with the theoretical values. Based on the measurement of temperature variation and strain, the settlement during the process of frame construction can be surely ascribed to thermal stress in the high redundancy structure. It should pay close attention to the changes in the future similar steel Beam Arch Composite Bridge construction and monitoring system.

This paper mainly introduces the strength curve of Yunnan regional standard for Technical specification for testing Compressive Strength of Masonry Mortar by Penetration Resistance Method. Furthermore, it researches the distinction in applicability and the accuracy between Yunnan regional and the national specification.

The study is limit-locking mechanism of space cable-strut deployable articulated mast. On the base of structure and working principle, the mechanism’s failure in ant-dislocation locking is analyzed and a new analytical model of reliability has been constructed. In the process of calculating reliability index, the factors such as size, assembly error, and space environment influence have been taken into consideration, and the method of MFOSM (Mean First Order Second Moment) has been applied. Based on the actual size of the mechanism, reliabilities of mechanism ant-dislocation locking have been calculated at both room temperature and space limit temperature. The main influencing factors have been analyzed and the improvement has been put forward. Calculations show that the new model has a high reliability in ant-dislocation locking.

The aim of the project is to study limit-locking mechanism of space cable-strut deployable articulated mast. Based on the discussion of structure and working principle, the mechanism's initial movement condition and self-locking angle are analyzed and a new analytical model of movement function reliability has been constructed. Combined with specific locking events, sliding pin's movement reliabilities are given in earlier and later stages. According to data from deployable mast, the reliability is calculated.

The microstructures of AA6111 automotive aluminum alloy were investigated by optical microscopy (OM), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), differential scanning calorimetry (DSC), X-ray diffraction analysis (XRD) and transmission electron microscope (TEM). The results indicated that as-cast AA6111 alloy has a complex microstructure. There were many kinds of intermetallic phases, such as lath-shaped β-Al5FeSi, Al15(FeMn)3Si2 and Mg2Si on the grain boundaries. The Al5Cu2Mg8Si6 precipitates presented non-equilibrium eutectic morphology in the grain interiors. After homogenization treatment (6h at 470), the low melting point Mg2Si phase began dissolving. The eutectic Al5Cu2Mg8Si6 phase were dissolved completely after 530/24h homogenization treatment. The Al15(FeMn)3Si2 phase started to be spheroidized at 560. Increasing treatment temperature will promote Mn to substitute for Fe in this phase.

Sufu is a traditional Chinese fermented food. The safety of spontaneous fermentation products has been concerned by more and more people. A total of four isolates with big clear halos on the casein medium plate were isolated from spontaneous fermented Sufu in southern Sichuan. A1 and A3 most likely belong to Bacillus cereus B according to their phenotype and Biolog Microbial Identification System. B2 was classified in group as Bacillus amyloliquefaciens B with the same methods. A2 was identified as Bacillus subtilis according to their phenotype and 16SrRNA. The safety of the strains are also discussed.

Coaled carbon-based solid acid (CCBSAC) is reported as a new, efficient and recyclable catalyst for the regioselective multicomponent synthesis of dihydropyrimidin-2(1H)-ones from aldehydes, β-ketoesters and urea or thiourea under solvent-free conditions. The structure and thermal stability of CCBSAC which resulted from ultra-clean coal resources mainly were characterized by IR, XRD, and TG. Nineteen dihydropyrimidin-2(1H)-ones examples were prepared and this catalyst could recycle up to 4 consecutive runs without losing its efficiency. The high yields of products, short reaction times, ease of work-up and clean procedure will make the present method a useful and important addition to the previous methodologies for the synthesis of dihydropyrimidin-2(1H)-ones.

Ecological safety problem from mining activities can not be ignored. Mining ecological security not only relates to ecological environment, also involves technology environment, political environment and cultural environment, etc. Through comprehensive analysis of situation and problems of mining ecological security, we can find Hengyang must go green mining road and must construct ecological mining from the environmental ecology, the political ecology and the cultural ecology, in order to realize mining sustainable development.

At present, according to Code for Design of Steel Structures（GB50017—2003）,for axially loaded column with plated column base, the column bases are considered as hinged supports, but possess actually remarkable rotational restraint. The effective length of columns can be decreased when the constraint function of plated column base is considered in calculation. The calculation of effective length factor of columns is usually according to the approximate formula which is deduced by the rotational stiffness. Axially loaded column plated column base models were established with the finite element software, the effective length factor of columns was obtained by the method which can avoid calculating rotational stiffness of plated column bases, the influence factors on the rotational restraint of axially loaded column plated column base, such as the base plate thickness, the diameter of anchors, the column section size were also analyzed in this paper.

We report herein for the first time the incorporation of a versatile organocatalyst, 4‐(N,N‐dimethylamino)pyridine (DMAP), into the network of a nanoporous conjugated polymer (NCP) by the “bottom‐up” approach. The resulting DMAP‐NCPmaterial possesses highly concentrated and homogeneously distributed DMAP catalytic sites (2.02 mmol g−1). DMAP‐NCPalso exhibits enhanced stability and permanent porosity due to the strong covalent linkage and the rigidity of the “bottom‐up” monomers. As a result, DMAP‐NCPshows excellent catalytic activity in the acylation of alcohols with yields of 92–99 %. The DMAP‐NCPcatalyst could be easily recovered from the reaction mixture and reused in at least 14 consecutive cycles without measurable loss of activity. Moreover, the catalytic acylation reaction could be performed under neat and continuous‐flow conditions for at least 536 h of continuous work with the same catalyst activity.

Surface tension is one of the main physical parameters of foams. The surface tension of Sodium Dodecyl Benzene Sulfonate （SDBS）solution and Triton solution are measured by the drop volume method，and at the same time CO2 saturated SDBS solution is also measured in this paper. It is found the solution concentration has an obvious effect on the surface tension. For SDBS solution, the surface tension gradually decreases with the increase of surfactant concentration while keeps constant after a certain concentration. For Triton solution, on the other hand, the surface tension always remains approximately constant in the studied concentration region. The surface tension of CO2 saturated SDBS solution is slightly higher than SDBS solution through experimental investigations.

According to the characteristics of the preparation and revision of a Department of steel production equipment used equipment, repair and maintenance procedures, design the whole process of the procedures from the preparation to the implementation, and propose a solution of approval procedures according to the concept of OA workflow. Meanwhile, implement a custom workflow with the concept of relational database design.

Based on the discrete time transfer matrix method(DTTMM), a dynamic model for a parachute-submissile system in the terminal descent phase is developed, thus avoiding the questions of multi-body dynamics based on traditional methods. The modeling process of a parachute-submissile system in the vertical plane is illuminated by adopting the D3TMM in detail and the transfer matrix and the transfer equation are deduced. Through an example, the validity of the model and the feasibility of DTTMM used in the deceleration parachute-submissile system are verified by comparing the parachute-submissile dynamic models based on the DTTMM and the Newton-Euler method. [ABSTRACT FROM AUTHOR]

In this paper Multi-Objective particle swarm optimization (MOPSO) algorithm is utilized to solve the problem for cooperative multiple target assignment, which is the optimization problem in the discrete search space. At first a model of multi-objective optimization for Cooperative Multiple Target Assignment is established. Aiming to solve out the local convergence phenomenon, the chaos mutation is introduced into PSO for improving global optimal ability. Another underlying problem is that computing speed of the algorithm must meet the operational requirement, so a new kind of Chaos-MOPSO Algorithm is developed to solve the target assignment problem with less population and iterations. At last an authentication example is given in this paper, compared with basic MOPSO and NSGA-II, the Chaos-MOPSO algorithm obtained a better Pareto solution set with smaller computational burden.

Panel mining requires constructing lots of artificial pillars in underground metal mines. Along with the development of the mining process the stress-strain state of pillars changes constantly. Finite element numerical simulation with Midas/GTS software is used to analyze the stability of the pillar during the entire process of panel mining and consider randomness and fuzziness for material parameters of concrete and ore rock to get stress distribution in the pillar. In this paper, the performance function and equation of dynamic fuzzy reliability for a pillar in the whole mining process are established and are solved by a program developed with the MATLAB software. Applying the proposed theory and procedures to dynamic fuzzy reliability analysis and calculation of the pillar was set in panel mining under complex conditions in Zhao Tong Lead-Zinc mine. The results indicate that dynamic fuzzy reliability can better reflect the pillar stability during the entire process of panel mining and the proposed theory and procedures are effective in evaluating the dynamic fuzzy reliability.

An experimental study of heat transfer characteristics of narrow rectangular channels with rib turbulators for Re in the range of 10000-60000 was performed. To simulate the actual geometry and heat transfer structure of blade/vane internal cooling passage, each of the test channels was welded by four stainless steel plates. Because of the three dimensional heat conduction in the walls and heat conduction between the ribbed and smooth walls, the measured temperature distribution along the axial direction of the test channel is a smooth continuous curve, and when the Re is low, the average Nu of the ribbed and smooth walls are nearly the same. For each aspect ratio channels, the average Nu for the channel of α=45° is about 15 to 25 percent higher than that of α=60°. In addition, we have developed the semi-empirical correlations, covering the range of Re, to predict heat transfer coefficient of the channels. The correlations can be used in the design of turbine blade/vane cooling channels.