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An endoplasmic reticulum (ER) targetable two-photon fluorescent probe termed ER-N3 is presented for the determination of hydrogen sulfide (H2S) in living cells and mice. The results demonstrate tha...

In this paper, the design and optimization process of a novel PM-assisted synchronous reluctance machine (PMASynRM) made of a blend of permanent magnets (Ferrite and NdFeB) will be presented. The design is targeting traction application and will be compared to a double-layer v-shaped IPM made of NdFeB magnets. The proposed design as well as the baseline design have the same stator and same thermal management approach. The main goal is to reduce rare-earth material content. The main challenges when it comes to reducing the rare-earth content are: (1) Maintaining the same rated torque as the baseline design (2) Eliminating the risk of demagnetization due to the lower coercivity of ferrites especially at low temperatures. The paper will focus on the optimization process with emphasis on evaluating the permanent demagnetization risk as well as design modifications considered to minimize/eliminate risk. The paper will also present a comprehensive comparison between the optimized design and the baseline design. It will be shown that around 40% reduction of rare-earth material can be achieved while maintaining the same average torque as the baseline design while minimizing/eliminating the demagnetization risk at the extreme low operating temperature of −20 °C. The paper includes details of the optimization process including sample results, evaluation of demagnetization risk and comparison of promising designs vs. the baseline design.

A new pH-sensitive fluorescent probe NAP-MDA was designed and synthesized. NAP-MDA consists of 1,8-naphthalimide as fluorophore, morpholine and N,N-dimethylethylenediamine as pH-responsive groups. Due to the photoinduced electron transfer (PET) mechanism, the fluorescence of 1, 8-naphthalimide was thoroughly quenched under alkaline condition (pH > 10.0), however, NAP-MDA displayed increasing fluorescence as the rise of acidity. Notably, NAP-MDA possessed an excellent linear dependence with neutral to alkaline pH (7.2–9.4), with a pKa of 8.38. NAP-MDA had good photostability and reversibility. Meanwhile, the probe was selective to pH without interference from common reactive species, temperature and viscosity. Fluorescent testing strips were fabricated with NAP-MDA and were successfully utilized to visualize the different pH with a handhold UV lamp. Confocal fluorescence imaging in live cells demonstrated that NAP-MDA mainly fluoresced in lysosomes, and could be applied for quantification of the pH within live cells.

Interaction of environmental pollution between peripheral areas has become a central topic in the field of resources and environment but little is known about the actual impact on peripheral areas ...

SBA-15 silica was synthesized by adding normal paraffin and alkyl benzene as swelling agents and using a low-temperature gelation procedure. Pd was then impregnated on SBA-15, yielding a catalyst. Characterizations of the catalyst by X-ray diffraction, N2 adsorption/desorption, scanning electron microscopy, transmission electron micrographs, X-ray photoelectron spectroscopy, in situ FTIR, and a hydrogenation test of 2-ethyl-anthraquinone reveal that the addition of C6‒C9 normal paraffin and 1,3,5-triisopropylbenzene could enlarge the pore diameter without a significant loss of ordered structure. Moreover, the length of SBA-15 pore channels decreased significantly. However, the sizes of Pd particles increase as the pore diameter is enlarged. The largest pore size (13.6 nm) and short length of pore channels (ca. 0.35 μm) are achieved by adding n-hexane. As a result, this catalyst exhibits the highest hydrogenation activity with an approximately 100% improvement, compared with a conventionally synthesized catalyst in the absence of a swelling agent.

Small molecule tyrosine kinase inhibitors (TKIs) targeting at epidermal growth factor receptor (EGFR) in recent years have made great progress in the treatment of advanced non-small cell cancer (NSCLC). Although as the first-line treatment for sensitizing EGFR mutation-positive metastatic NSCLC, gefitinib has also behaved quite a lot of side effect and EGFR tolerance. Herein, a novel series of 7-bromo-1,4-dihydrothieno[3’,2’:5,6]thiopyrano[4,3-c]pyrazole-3-carboxamide derivatives were designed and synthesized, and screened for their inhibitory activity on the EGFR high-expressing human lung adenocarcinoma cell line A549 and human large cell lung cancer cell line NCI-H460 by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide colorimetric assay. The calculated IC50 values were reported. Compound 8h demonstrated the most potent inhibitory activity (IC50 = 9.57 ± 2.20 μmol L–1 for A549 and IC50 = 13.04 ± 1.21 μmol L–1 for NCI-H460), comparable to the positive-control gefitinib (IC50 = 8.58 ± 1.65 μmol L–1 for A549 and IC50 = 18.66 ± 5.01 μmol L–1 for NCI-H460). Conclusively, 7-bromo- 1,4-dihydrothieno[3’,2’:5,6]thiopyrano[4,3-c]pyrazole-3-carboxamide derivatives as the EGFR–TKIs were discovered, and could be used as potential leading compounds for further research.

Pd catalysts on mesoporous silica SBA-15 functionalized with alkyltriethoxysilane (alkyl = methyl, ethyl, propyl and isobutyl) were prepared. The effects of grafting sequence on the grafting amount were studied. The catalysts were characterized by XRD, FT-IR, elemental analysis, thermogravimetric analysis, nitrogen adsorption-desorption, TEM and XPS, and evaluated using catalytic hydrogenation of 2-ethyl-anthraquinone. The grafting amount increases with increasing the alkyl chain length of alkyltriethoxysilane. The highest grafting amount with the carbon content of 1.56% is obtained using an ante-grafting procedure where the grafting is performed prior to the removal of template, and this catalyst shows the highest activity and selectivity (98.3%). The accordant relationship between the activity of Pd/SBA-15 catalysts and their grafting amount indicates a positive effect of hydrophobicity of SBA-15 created by grafting on the catalytic hydrogenation of 2-ethyl-anthraquinone.

By using a multicalcination procedure, Co-doped Bi4NdTi3Fe 1 − x CoxO15 ( x = 0.1 , 0.3 , 0.5 and 0.7 ) (Cox) ceramics were synthesized. The samples showed a single-phase (SP) Aurivillius structure containing four perovskite layers. Plate-like morphology of the grains which is related to the layered perovskite structure of the samples was clearly observed by SEM. The multiferroic properties of the samples at room temperature (RT) were demonstrated by dielectric, ferroelectric and magnetic measurements. With x ranging from 0.1 to 0.7, all the samples show RT multiferroic properties although there is no obvious regularity between the Co content and the multiferroic property. Very interestingly, Co0.3 sample exhibits the optimum RT magnetic property, which can be attributed to the inclination of occupying the inner octahedra center for doped Co ions and the nearly 1:1 ratio of Fe and Co ions in the inner octahedra. The present work offers new insight into the compositional design of promising lead-free RT multiferroic materials.

Aurivillius Bi4NdTi3(Fe0.5M0.5)O15 (M-BNTF, M = Cr, Ni, Fe, Co, Mn) thin films were prepared by a sol-gel method. Single-phase four-layered perovskite structure of all the M-BNTF thin films was characterized by X-ray diffraction and FT-IR spectra. Typical plate-like grains with different grain sizes were observed in the M-BNTF thin films. Optical properties were measured by a UV–vis spectrometer, and all the films have direct bandgaps. The bandgaps of the Cr-, Ni-, Fe-, Co- and Mn-BNTF films were calculated to be about 3.45, 2.84, 2.58, 2.47 and 2.37 eV respectively through the Tauc's power law. The bandgap tuning is attributed to the cationic disorder and the large distortion of MO6 octahedron by the M ions doping which was verified by the calculation of lattice parameters and Raman measurements. The present work may help shed light on the origin of the bandgap tunability for bismuth-contained Aurivillius ferroelectric compounds and promote them to get more extensively application in the new photovoltaic cells and other novel optoelectronic devices.

The Bi3.15Nd0.85Ti3O12 (BNdT) and Cr-doped BNdT films on quartz substrates were prepared by a sol-gel process and the effects of Cr doping on the structure and band gap of BNdT were examined. Cr-doping does not change the three-layered perovskite structure of BNdT but transforms the grain morphology from equiaxed grains to rectangular grains. The utilization of visible light is increased by Cr doping and the large band gap reduction (∼1.1 eV) was obtained, which is analyzed from the electronegativity and the distortion caused by substitution. The present work provides an available way to make ferroelectric (FE) BNdT getting more extensively applied in the new photovoltaic cells and other novel optoelectronic devices.

In order to analyze variable-mass permeation characteristics of broken rock mass under different cementation conditions and reveal the water inrush mechanism of geological structures containing broken rock masses like karst collapse pillars (KCPs) in the coal mine, the EDEM-FLUENT coupling simulation system was used to implement a numerical simulation study of variable-mass permeation of broken rock mass under different cementation conditions and time-dependent change laws of parameters like porosity, permeability, and mass loss rate of broken rock specimens under the erosion effect were obtained. Study results show that (1) permeability change of broken rock specimens under the particle migration effect can be divided into three phases, namely, the slow-changing seepage phase, sudden-changing seepage phase, and steady seepage phase. (2) Specimen fillings continuously migrate and run off under the water erosion effect, porosity and permeability rapidly increase and then tend to be stable, and the mass loss rate firstly rapidly increases and then gradually decreases. (3) Cementation degree has an important effect on permeability of broken rock mass. As cementing force of the specimen is enhanced, its maximum mass loss rate, mass loss, porosity, and permeability all continuously decrease. The study approach and results not only help enhance coal mining operations safety by better understanding KCP water inrush risks. It can also be extended to other engineering applications such as backfill paste piping and tailing dam erosion.

In this work, we have developed a low-cost and green strategy for nanoscale zero-valent iron (ZVI) in situ encapsulated in lignin-derived hydrochar (Fe@HC) by a facile one-pot synthesis route. The as-synthesized Fe@HC was characterized for physicochemical properties by X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), transmission electron microscope (TEM), thermal gravimetric analysis (TGA), and Fourier-transform infrared spectroscopy (FT-IR). Further catalytic experiment revealed that phenol could be completely degraded by Fe@HC-800 within 20 min with peroxymonosulfate (PMS) at mild temperatures. Fe@HC-800 catalyst also exhibited stable performance after three runs of regeneration. The XPS and XRD results proved the key role of Fe0 in the degradation of phenol. This approach is of great potential to the development of green materials biomass-derived carbon materials for wastewater treatment applications.

Organosilane-functionalized mesoporous silica SBA-15 was prepared by the co-condensation method and then applied as a support of Pd catalysts for hydrogenation of 2-alkyl-anthraquinone (AQ, alkyl = ethyl, tert-butyl and amyl). The as-prepared Pd catalysts were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, N2 adsorption–desorption, zeta potential, water contact angles measurement and transmission electron microscopy. By extending the pre-hydrolysis time of the silica source, the content of functional groups in the catalysts slightly increases. However, there is an initial increase in zeta potential and water contact angles up to a maximum at 2 h, followed by a decrease as the pre-hydrolysis time was further prolonged. The hydrophobicity created by organic functionalization has positive effects on AQ hydrogenation. The catalyst with the highest hydrophobicity exhibits the highest catalytic activity, with increments of 33.3%, 60.0% and 150.0% for hydrogenation of ethyl-, tert-butyl- and amyl-anthraquinone compared with the unfunctionalized one.

This paper is a contribution to answering the following question: Is it possible to design a permanent-magnet machine with the performance expected from rare-earth magnets, but at a lower cost? Performance being understood as torque, size, efficiency, demagnetization and temperature rise together. The question is addressed with a systematic exploration of different interior permanent-magnet machine topologies mixing rare-earth and ferrite permanent magnets. The study starts from a production baseline, the Prius 2010 traction motor, with interior magnets placed in a single V pattern. It investigates various rotor designs, most specifically, single V and double V patterns as well as spoke configurations. The stator cross-section design and winding selection are fixed, providing a solid comparison basis from the point of view of machine cooling. For each rotor design, torque potential and machine material cost are assessed, the latter expressed as torque per dollar. A promising configuration was found, based on a spoke pattern, for which further modeling was performed to assess efficiency as well as resistance to demagnetization. It reduces the rare earth magnet volume by over 60%.

The acquisition of susceptibility to necrotrophy over the course of ripening is one of the critical factors limiting shelf life. In this study, phytopathology and molecular biology were employed to explore the roles of pectinase in fruit susceptibility and ripening. Solanum lycopersicum fruit softened dramatically from entirely green to 50% red, which was accompanied by a continuously high expressed SlPG2 gene. The necrotrophic fungus Botrytis cinerea further activated the expression of SlPGs and SlPMEs to accelerate cell wall disassembly, while most of the polygalacturonase inhibitor proteins encoding genes expression were postponed in ripe fruit following the pathogen attack. Pectin induced the antagonistic yeast to secrete pectinolytic enzymes to increase fruit resistance against gray mold. The activities of pathogenic pectinase of B. cinerea were correspondingly depressed in the pectin-inducible yeast enzyme elicited ripe fruit. These data suggest that pectinase is a molecular target for regulation of disease resistance during fruit ripening.

A gas–solid coupling model involving coal seam deformation, gas diffusion and seepage, gas adsorption and desorption was built to study the gas transport rule under the effect of protective coal seam mining. The research results indicate: (1) The depressurization effect changes the stress state of an overlying coal seam and causes its permeability to increase, thus gas in the protected coal seam will be desorbed and transported under the effect of a gas pressure gradient, which will cause a decrease in gas pressure. (2) Gas pressure can be further decreased by setting out gas extraction boreholes in the overlying coal seam, which can effectively reduce the coal and gas outburst risk. The research is of important engineering significance for studying the gas transport rule in protected coal seam and providing important reference for controlling coal and gas outbursts in deep mining in China. Keywords: Protective coal seam mining, Seepage characteristic, Coal and gas outburst, Numerical simulation

To dig the different structural and functional characteristics of the network, the research on complex networks focus in the field ranges from mesoscopic perspective on community structure to microscopic perspective on importance of nodes. However, most of these researches fail to make a combination of community detection and influential nodes. Based on the current study, we proposes a new index to identify influential nodes combined with the structural hole theory in sociology. The algorithm evaluates node importance by considering its neighbors connected to its own communities and connected other communities outside. The experimental results show that the indicator we proposed has advantages over the existing classical node importance indicators in the network with obvious community structure.

This paper proposes a novel approach to calibrate the intrinsic camera parameters from a single image, which includes the silhouette of two spheres and two ellipses generated by the intersection between the line-structured laser light and the two spheres. This approach uses the vanishing line of a plane and its normal direction to calculate the orthogonal constraints on the image of absolute conic (IAC). And this plane is formed by the camera center and two sphere centers. In addition, the pair of the circular points of the light plane is calculated from the generalized eigenpairs from the intersection between the light plane and the spheres. The intrinsic parameters of the camera can then be recovered from the derived orthogonal constraint and the pair of circular points on the IAC. Furthermore, the 3D positions of these two sphere centers under the camera coordinate can be recovered from the camera intrinsic matrix and then used to evaluate the accuracy of the camera intrinsic matrix. Experiment results on both synthetic and real data show the accuracy and the feasibility of the proposed approach.

One of essential issues that attract most scholars' concern is to identify a set of influential spreaders in a large network so that they can spread influence to the largest range on the network with a little effort. Traditional methods for mining influential nodes on the complex networks mostly focus on unweighted undirected networks, which fail to reveal a lot of details on the real systems. However, researches for detection important individuals on the weighted directed network are few, but also ignore some of essential influencer due to merely consider edge direction as a factor impact node's importance. Based on the existing research, we distinguish the contribution of in-degree and out-degree to the importance of the node and put forward a method on the weighted directed network based on ClusterRank to identify the influential spreaders by considering the influence of both edge weights and direction to the node importance. The results show that the important nodes identifying by IO-ClusterRank algorithm has similar influence as other methods on networks which distribution of in-degree and out-degree is approximately symmetric, but have more influence ability and faster spreading speed on other kinds of networks. Furthermore, it still remain a lower time complexity same as original method because of unchanged local characteristics.

Torque ripple and acoustic noise are two major drawbacks to switched reluctance motors. The abrupt change of phase current is main cause of acoustic noise, while both commutation and current wave shape are two major factors contributing to high torque ripple. In order to simultaneously reduce torque ripple and noise, a specific current modulation based on real inductance profile can be employed to recently proposed pseudo-sinusoidal switched reluctance motor (PSSRM). Performance comparison including torque ripple, acoustic noise and efficiency with conventional square and half-sine current modulations are investigated. The performance of the specific current modulation is verified by simulations and experiments with a 12/16, three phase 0.4-hp PSSRM. The results show torque ripple and acoustic noise can be simultaneously reduced with a comparable efficiency by the proposed current modulation method.