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Ultraviolet (UV) detector based on β-Ga2O3/p-GaN was fabricated in this paper. The growth process involved deposition of amorphous Ga2O3 layer by means of magnetron sputtering and conversion of β-Ga2O3. The obtained detector displays excellent UV sensing properties which covers Ultraviolet A(UVA)/Ultraviolet C(UVC) region with fast response. It will provide a new route to fabricate β-Ga2O3/p-GaN heterostructure for applications in broadband ultraviolet sensing.

The combination of graphene oxide (GO) and iron oxide (Fe2O3) may induce property enforcement and application extension. Herein, GO/Fe2O3 nanocomposites were synthesized via the vacuum-freeze-drying method and used for the thermal decomposition of ammonium perchlorate (AP). A series of characterization techniques were applied to elucidate the as-obtained nanomaterial's physicochemical properties. These results show that the treated GO is consistent with the pristine GO after the freeze-drying treatment. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analyses show that iron oxide nanoparticles are anchored on and between the GO sheets. The catalytical effect investigation on AP with different Fe2O3: GO ratios indicates that the high-temperature decomposition temperature of AP could be decreased by a temperature as high as 77 °C compared to pure AP accompanied by 3 wt % GO/Fe2O3 nanocomposite which proves the high catalytic performance of the nanocomposites. The first-principles calculation was employed to elaborate the synergistic effect, and the findings demonstrate that the presence of graphene in the catalyst can enhance the catalytic effect via reducing the activation energy barrier by ∼17% in the reaction of AP thermal decomposition.

By maintaining high piezoelectric coefficients (d33), increasing the depolarization temperature is the key to constructing high-performance high-temperature piezoceramics. Unfortunately, so far, no piezoceramic has been found that still has a d33 value above 700 pC N−1 by in situ testing at a high-temperature of 400 °C. For popular 0.36BiScO3-0.64PbTiO3 ceramics with a MPB structure, the in situ quasi-static d33 value at 400 °C is only 405 pC N−1. Herein, a new strategy to enhance perovskite lattice distortion to obtain oxides with excellent high-temperature piezoelectricity has been proposed. By introducing Bi(Zn0.5Hf0.5)O3 to enhance lattice distortion of a (1 − x)BiScO3-xPbTiO3 matrix, a ternary system zBiScO3-xPbTiO3-yBi(Zn0.5Hf0.5)O3 (zBS-xPT-yBZH) was designed. A record-high in situ quasi-static d33 value of 726 pC N−1 at 400 °C is achieved in a 0.355BS-0.635PT-0.01BZH composition. Structural analysis confirmed that the introduction of highly tetragonal Bi(Zn0.5Hf0.5)O3 can enhance the lattice distortion and the sample annealed at 400 °C still maintains a stable domain configuration. Moreover, a high-temperature piezoelectric energy harvester is manufactured from the optimal material, and exhibits excellent high-temperature power generation capacity, and a 10 μF commercial electrolytic capacitor can be easily charged to 0.9 V in 40 s at 400 °C. This work demonstrates that zBS-xPT-yBZH ceramics have great potential for application in extreme high temperature environments, and pave the way for obtaining high-quality high-temperature piezoelectric materials.

The self-assembly of plasmonic nanoparticles into highly ordered superlattices could pave the way toward novel nanomaterials for surface-enhanced Raman scattering (SERS). Here, we propose the formation of large-area superlattices of elongated rhombic dodecahedra in a vertical orientation via a controlled droplet evaporation process. Expectedly, the constant humidity of the experimental condition could control the evaporation speed of droplets and this procedure promotes the balance between driven depletion attraction and electrostatic repulsion in the system, leading to the generation of well-organized three-dimensional (3D) superlattices. The unique geometry of elongated rhombic dodecahedra could establish the tetragonal superlattices, which breaks the conventional hexagonal symmetry of gold nanorods. Specifically, the influence of the type and concentration of surfactants, the concentration of nanoparticles, and the amount of droplets on the preparation results were systematically investigated to find the optimal assembly parameters. Remarkably, such close-packed tetragonal arrays of vertically aligned elongated rhombic dodecahedra exhibit more excellent SERS performance compared with the traditional hexagonal superstructure of gold nanorods. Benefiting from the high sensitivity and reproducibility of elongated rhombic dodecahedron superlattices, their applications in the determination of pesticide residues in apple and grape peels were successfully demonstrated. As a result, this study may advance the production of innovative plasmonic nanomaterials for a broad range of fields.

In this article, ultra-broadband photoluminescence in near-infrared is achieved in KZnF3 glass ceramics doped with Er3+and Ni2+ ions. Er3+-Ni2+ co-doped fluorosilicate glass and glass ceramics embedded with perovskite nanocrystals were fabricated and efficient energy transfer (ET) from Er3+ to Ni2+ ions was confirmed by luminescence spectra and decay curves. In the glass ceramic samples, Ni2+ ions were effectively sensitized by Er3+, and ultra-broadband photoluminescence from 1400 to 2300 nm was observed when a 980 nm laser was used as a pump, as shown in Fig. 1. The temperature and humidity stability of the glass ceramic samples was characterized from the measured transmittance. These results demonstrated that Ni2+-Er3+ co-doped glass ceramics have significant potential for application in optical communication and broadband amplifiers.

A new organic–inorganic hybrid, namely [Ni2(en)4(C2H3NO2)(H2O)][Ni(en)3][Ni(en)2][P2W18O62]·6H2O (1, en = 1,2-ethylenediamine), was synthesized hydrothermally by mixing the ligands of 1,2-ethylenediamine and glycine. Notably, compound 1 exhibits the first example of coordination polymer derived from the Wells–Dawson polyoxoanions and di-nuclear nickel(II)-glycine cations. As a result, an intriguing 3D supramolecular architecture was fabricated with the [P2W18O62]6− fragments and the nickel counter-cations via hydrogen bonds. Furthermore, the compound with this unique structure exhibited outstanding electrocatalytic properties in terms of the reduction of iodate and nitrite. This work brings a new inspiration for the design and synthesis of new hybrids with functional behaviors towards various fields of catalysis.

Monitoring the dynamic humidity requires sensors with fast response and anti-electromagnetic interference, especially for human respiration. Here, an ultrafast fiber-optic breath sensor based on the humidity-sensitive characteristics of gelatin film is proposed and experimentally demonstrated. The sensor consists of a microknot resonator superimposed on a Mach-Zehnder (MZ) interferometer produced by a tapered single-mode fiber, which has an ultrafast response (84 ms) and recovery time (29 ms) and a large dynamic transmission range. The humidity in dynamic ambient causes changes in the refractive index of gelatin coating, which could trigger spectral intensity transients that can be explicitly distinguished between the two states. The sensing principle is analyzed using the traditional transfer-matrix analysis method. The influence of coating thickness on the sensor's trigger threshold is further investigated. Experiments on monitoring breath patterns indicate that the proposed breath sensor has high repeatability, reliability, and validity, which enable many other potential applications such as food processing, health monitoring, and other biomedical applications.

Soluble sugars play important roles in plant development and stress response, and the nitrogen supply level can affect the among-organ distribution and metabolism of sugar in plants and, in turn, plant growth. To explore the adaptive response of apple root growth to nitrogen supply and its relationship with sugar metabolism, we used a hydroponic culture system to study how the nitrogen supply affects soluble sugar concentrations and sugar metabolism in apple roots. In hydroponic seedlings of Malus hupehensis, low nitrogen application caused rapid and vigorous proliferation of lateral roots, and the transcript levels of MdSOT1 and MdSUT3, which are involved in photoassimilate unloading in roots, were upregulated. The accumulation of sorbitol and sucrose in the fine roots was higher, and the activities of sucrose synthase, invertase and sorbitol dehydrogenase, which are involved in the degradation of sucrose and sorbitol, were significantly increased under a low nitrogen supply. Genes involved in sugar degradation, such as MdSDH1, MdSuSy5, and MdNINV3, play important roles in the efficient use of sorbitol and sucrose under nitrogen deficiency. Additionally, the activity of fructokinase and hexokinase, which are involved in hexose phosphorylation, and transcript levels of MdFRK2 and MdHK3 were significantly upregulated under nitrogen deficiency, and the hexose phosphate products F6P and G6P accumulated greatly in the roots. These results showed that the sugar metabolism capability and sink strength of the roots increased under low nitrogen, indicating that low nitrogen promotes the utilization of sugar in the roots to meet the demand for sugar under rapid root growth.

Graphene and carbon nanotube (CNT) are representative carbon nanomaterials which have aroused numerous research interest due to their extraordinary material properties and promising application potentials, especially in the energy storage and conversion areas. However, the agglomeration happening in these materials has largely blocked their applications. Hybridization of CNT with graphene can, on one hand, prevent the agglomeration behavior, on the other hand, generate a synergistic effect between them with enhanced physical and chemical properties. There have been many studies conducted to find out the suitable approaches to synthesize graphene/CNT composites, and realize the application potentials of these structures. Based on the recent advances, this paper reviews the current research progress that has been achieved in synthesizing graphene/CNT composites, and the energy-related applications. Through this review, we aim at stimulating more significant research on this subject.

Schisandrae chinensis fructus (Wuweizi) contains many triacylglycerols (TAGs). Therefore, it is inevitable that these TAGs will be part of Chinese medical preparations of Schisandrae chinensis fructus. It is important to identify TAGs in Schisandrae chinensis fructus. Fatty acids in Schisandrae chinensis fructus oil were identified by gas chromatography−mass spectrometry (GC−MS) after transesterification. TAGs were determined by liquid chromatography−mass spectrometry (LC−MS) and confirmed by high-resolution Fourier transform-ion cyclotron resonance-mass spectrometry (FT−ICR−MS). Seven kinds of fatty acids were detected in Schisandrae chinensis fructus oil of which linoleic acid (L) and oleic acid (O) accounted for 93%. Also, 7 TAGs were recognized in the oil. LLL, OLL, OOL and PLL were the main components (P corresponds to palmitic acid). The LLL composed approximately half of the oil of Schisandrae chinensis fructus by mass. The composition of fatty acids and TAGs in Schisandrae chinensis fructus was determined by GC−MS, LC−MS and FT−ICR−MS.

With the popularization of carbon and nitrogen stable-isotope analysis methods used on archaeological samples from Xinjiang, the ancient paleodiet there has been revealed. However, research about isotopic analysis combined with environmental factors is rare, especially in such a variable and complex climate as that of the Tianshan region. We systematically analyzed the δ13C and δ15N results from animals and humans for dietary reconstruction of nomadic pastoralists from the Tianshan region during 3900–1200 cal BP. The δ13C and δ15N values for animals (sheep/goat, horse and cattle; n = 57) have a wide range from –20.8‰ to –14.7‰ for δ13C (–19.2 ± 1.0‰) and 3.2‰ to 9.9‰ for δ15N (7.0 ± 1.2‰). The δ13C and δ15N values from humans range from –19.6 to –12.3‰ (–16.0 ± 1.5‰) and 7.1 to 16.7‰ (–13.6 ± 1.5‰), respectively. The animal δ15N results indicate that the dry environment in the Tianshan region may result in elevated δ15N values. Synthesizing animal and human isotope results suggests that the inhabitants engaged in mobile herding economies subsidized with crops and wild animal meat from the Tianshan Mountains. In conclusion, we found that the regional environment closely relates to crop types, and temporal climate change has an effect on human dietary structure. Therefore, climate condition cannot be ignored when studying human paleodiet.

Ho3+ doped and Ho3+/Tm3+ co-doped fluoroindate glass samples were prepared and their emission properties were compared. Under 888 nm laser excitation, the emission at 2 μm of Ho3+ ions with co-doping 2 mol% Tm3+ ions had a 2.9-fold improvement compared with that of Ho3+ doped. The absorption and emission spectra, and energy level lifetime of Ho3+/Tm3+ co-doped glass samples were measured to analyze the energy transfer processes and enhancement mechanisms. The luminescence intensity at 2 μm can be greatly increased due to the bidirectional energy transfer between Tm3+ and Ho3+ ions.

In this study, the multifunctional carbon nitride based composite graphitic-C3N4 (g-C3N4)/TiO2/Ag was prepared through a simple and efficient vacuum freeze-drying route. TiO2 and Ag nanoparticles were demonstrated to decorate onto the surface of g-C3N4 sheet. In the ultraviolet–visible absorption test, a narrower band gap and red-shift of light absorption edge were observed for g-C3N4/TiO2/Ag compared to pristine g-C3N4 and single-component modified g-C3N4/TiO2. The photodegradation property of g-C3N4/TiO2/Ag was investigated toward the degradation of methylene blue (abbreviated as MB) under the irradiation of visible light. These results indicated that the degradation performance of organic dyes for g-C3N4/TiO2/Ag was obviously improved compared with g-C3N4/TiO2 and g-C3N4. The reaction rate constant of MB degradation for g-C3N4/TiO2/Ag was 4.24 times higher than that of pristine g-C3N4. In addition, such rationally constructed nanocomposite presented evidently enhanced antibacterial performance against the Gram-negative Escherichia coli. Concentration dependent antibacterial performance was systematically investigated. And 84% bacterial cell viability loss had been observed at 500 μg/mL g-C3N4/TiO2/Ag within 2 h visible light irradiation.

peer-reviewed Up-conversion luminescence and C-band microsphere laser output is reported for an Er3+-doped ZrF4-BaF2-YF3-AlF3 (ZBYA) fluorozirconate glass microsphere. The microsphere was fabricated by heating a ZBYA glass filament using a CO2 laser beam. The fabrication process accurately and repeatably produces microspheres of 68 μm diameter. The input and output laser light was coupled to the microsphere using a tapered optical fiber. The coupling position between the tapered fiber and microsphere was adjusted using a sophisticated three-dimensional translation stage. The up-conversion luminescence emission, single-mode and multi-mode laser at C-band (1530 to 1565 nm) were observed when pumped using a 980 nm laser.

Improving the operating characteristics of piezoelectric devices in high temperature environments urgently requires the development of piezoceramics with both high piezoelectric coefficient and excellent temperature stability. However, it is difficult for existing piezoceramics to take care of both at the same time. Generally, high piezoelectricity can be obtained at morphotropic phase boundary (MPB) in the binary systems, such as PbZrO3–PbTiO3 and Pb(Mg1/3Nb2/3)O3–PbTiO3, but the temperature stability is unsatisfactory, which seriously restricts the practical application. Here, an optimum composition having excellent comprehensive properties is constructed by designing multiple MPBs in the novel xPb(In1/2Nb1/2)O3-yBiScO3–zPbTiO3 ternary system. When x = 0.04, y = 0.345 and z = 0.615, the specimen has a high piezoelectric coefficient d33 of 478 pC/N at 200 °C, meanwhile, the fluctuation of d33 is less than ± 10% over an ultra-broad temperature range of 50–350 °C. Combined with a variety of in situ analysis techniques, it can be determined that the temperature-insensitive high piezoelectric coefficient is related to the multiple MPBs design, which is beneficial to the optimization of the hierarchical domain configuration. The developed phase boundary design strategy paves a new way to building next generation high performance high temperature piezoceramics.

Polyimide microfluidic devices (MFDs) have been attached enormous significance because of its excellent organic-solvent inertness, biocompatibility, and thermal stability. In this paper, a novel fabrication method based on the thought of additive manufacturing, which is adding materials layer by layer from bottom to top, was used to construct a multilayer polyimide MFD. The MFD has sophisticated three-dimensional (3D) microchannels with adjustable cross-sectional geometries and high bonding strength, which leads to good reagent mixing performance, large surface-to-volume ratio, and great durability. Starting from a single polyimide film, ultraviolet (UV) laser was utilized to ablate microchannels on the film. Due to the studies over the influence of UV laser on the channel width, the microchannel edge shape is under control, varying from trapezoid to rectangle. From monolayer to multilayer MFDs, thermal bonding with fluorinated ethylene propylene (FEP) nanoparticle dispersion as the adhesive was adopted to stack polyimide films tightly with precise alignment. In this way, microchannels can be connected vertically between layers to form 3D structures. Besides, a homogeneous adhesive interlayer and polyimide-FEP mixing regime were formed, which can provide high bonding strength. Results of computational fluid dynamics simulation of 3D microchannel structures and organic synthesis experiment revealed that our device has great reagent mixing efficiency and promising application prospects in diverse research fields, especially organic chemical and biological studies.

Fe2O3 short nanorods, nanorods and nanowires were prepared by a facile hydrothermal method by using different flexible ligands (oxalic acid, succinic acid, adipic acid) as templates to adjust the L/D (length/diameter) ratios of the one-dimensional (1D) Fe2O3–nanostructures for the first time. The growth mechanism of Fe2O3 nanorods and nanowires were proposed. Their potential applications as anodes for lithium ion batteries were investigated by electrochemical analysis. This novel straightforward strategy to fabricate 1D metal oxide with different L/D ratios may provide a promising method to make advanced Fe2O3-based nanostructures for Li-ion battery applications.

An efficient and facile strategy for producing core-shell Au@Ag nanorods (NRs) with controllable width and length as excellent surface enhanced Raman scattering (SERS) substrate was proposed. Au nanodipyramids (NDPs) of three various widths were prepared by overgrowth along the radial orientation, and together with Au NDPs as seed, silver was deposited in the axial orientation to successfully obtain core-shell Au@Ag NRs with diverse length (73 nm–157 nm) and width (25 nm–43 nm). The morphology, optical properties and SERS performance of the as-synthesized Au@Ag NRs were investigated systematically. The broadly tunable UV-Vis absorption range for Au@Ag NRs as far as the near-infrared (NR) region was able to be obtained. Furthermore, the SERS property of Au@Ag NRs two-dimensional monolayer was explored by using crystal violet (CV) as Raman probe. The optimal SERS enhancement effect with enhancement factor (EF) as high as 6.13✕105 could be achieved for Au@Ag NRs with wider width and longer length, which was confirmed by the simulation results of electromagnetic (EM) field distribution by FDTD method. Our novel approach provides some facinating insights into adjusting the width of Au@Ag NRs, which also significantly influences the SERS behaviors of the Au@Ag NRs. It allows to fabricating SERS substrate with superior SERS performance compared to previously reported Au@Ag NRs only with tunable length via direct overgrowth. Besides, this as-compounded Au@Ag NRs are expected to have promising application and significant value in other fields.

The Pre-Caspian basin is one of the most prolific in terms of oil and gas exploration and hydrogen and carbon compounds energy production around the world. The major hydrogen and carbon compounds reservoirs are Carboniferous reef and platform hydrogen-carbonate rocks. The original fluids under subsurface conditions contain 15% hydrogen sulfide and 4% carbon dioxide. Acid hydrogen and carbon compounds reinjection is not only an environmentally friendly solution for disposal of produced greenhouse gases but also enhances oil recovery and supplies more fuel energy. On the other hand, the presence of fractures makes hydrogen-carbonate reservoir characteristics nature more complicated than conventional sandstone reservoirs, which leads to a tremendous challenge to evaluate the gas injection process. In this work, a dual-porosity dual-permeability formulation was used to model the dual-medium nature incorporating matrix system with high porosity and low permeability and fracture network with low porosity and high permeability. After matching PVT experiments, a ten pseudo-components fluid model was generated for running compositional simulation. The miscible hydrogen and carbon compounds injection was simulated as an effective enhanced oil recovery approach. Sensitivity analysis such as timing of injection gas, injection rate, well spacing and completion interval have proposed the optimal condition for the miscible hydrogen and carbon compounds flooding. The recommended optimum hydrogen and carbon compounds injection scenario is twice higher oil recovery compared with natural depletion. The results of this study illustrate further the practicability of pseudo-components splitting and lumping for compositional simulation to evaluate the performance of hydrogen and carbon compounds injection processes, and are of great importance using the dual-porosity dual-permeability method performing numerical simulation of naturally fractured hydrogen-carbonate reservoirs.

The lead-free (1−x)(0.8Na0.5Bi0.5TiO3-0.2 K0.5Bi0.5TiO3)-xBi(Mg2/3Nb1/3)O3 ceramics were prepared using pressureless solid-state sintering for compositions x ≤ 0.4. At 120 °C, the recoverable energy storage density (Wrec) of x = 0.2 sample reached as high as 0.80 J/cm3 under the electric field of 90 kV/cm, significantly better than the other literature reported Na0.5Bi0.5TiO3 based samples. The fine-grained sample maintained high insulation resistivity (1011 Ω·m order) from 25 °C to 200 °C, which contributes to large breakdown electric field at high temperatures and leads to the excellent energy storage characteristics. This work could broaden the applications of Na0.5Bi0.5TiO3 based materials in building high-temperature multi-layer energy storage capacitor.

This work reports a microsphere laser at ∼2.0 μm in a Tm3+-doped ZrF4-BaF2-YF3-AlF3 (ZBYA) fluoride glass. The ZBYA glass microsphere was fabricated by reflowing the tip of a 1.0 mol% Tm3+-doped ZBYA glass fiber with a CO2 laser. By using a fiber taper for input and output coupling in the Tm3+-doped ZBYA microsphere, single and multi-mode laser outputs at around 2.0 μm were observed under 808 nm laser excitation. The radiation lifetime and emission cross-section of Tm3+ ions in ZBYA glass were calculated to be 6.42 ms and 5.86 × 10−21 cm2, respectively. Our results indicate that the Tm3+-doped ZBYA fluoride glass has potential applications for 2.0 μm lasers.

A new type of electrochemical sensor based on multi-walled carbon nanotubes(MWCNTs), K2H4SiW11CuO39·6H2O(SiW11Cu) and gold nanoparticles(AuNPs) was prepared for the simultaneous detection of bisphenol A and acetaminophen. Differential pulse voltammetry(DPV), cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS) were used for electrochemical characterization, and Fourier transform infrared spectroscopy(FTIR) was used to characterize the structure of polyoxometalates. Electrochemical experimental results show that the composite modified electrodes have good electrochemical activity as well as current response values of bisphenol A and acetaminophen when pH=7.0. At the same time, the modified electrode exhibits good stability and reproduction, and has good anti-interference ability to other substances. In practical application, the sensor obtained satisfactory results.

We describe the synthesis and properties of a series of sulfonium boranes featuring a dimesitylboryl unit and a dimethylsulfonium or methylphenyl sulfonium moiety connected by an ortho- or para-phenylene linker. Acid-base and fluoride anion tritration experiments carried out in aqueous media indicate that [o-(Mes2B)C6H4(SMePh)]+ is the most Lewis acidic derivative. Structural and computational analysis indicate that the favorable properties of this cationic borane derive from the proximity of the sulfonium and boryl units which enhances the Coulombic stabilization of the ensuing zwitterions o-(Mes2XB)C6H4(SMePh) with X = OH or F. Another important factor is the overall hydrophobicity of the sulfonium borane which, we propose, promotes anion desolvation, a factor also favoring B-X bond formation. Finally, the crystal structure of o-(Mes2FB)C6H4(SMePh) shows that the zwitterion is further stabilized by formation of a B F→S chelate motif.

Thermal depolarization is an insurmountable obstacle to the application of piezoceramics and there is still controversy about its physical origin. In this work, taking four representative piezoceramics (0.94(Na0.5Bi0.5)TiO3-0.06BaTiO3, 0.2Pb(Zn1/3Nb2/3)O3-0.8Pb(Zr0.5Ti0.5)O3, 0.36BiScO3-0.64PbTiO3 and Ba0.85Ca0.15Ti0.9Zr0.1O3) as an example, by using a designed in-situ Berlincourt-type high-temperature d33 meter, combined with variable temperature X-ray diffraction and dielectric temperature spectrum test, it was confirmed the depolarization behavior is directly related to the structural phase transition, meanwhile it is reasonable to apply the peak value of piezoelectric coefficient with temperature, Tdp, as the depolarization characteristic temperature. More importantly, the original in-situ varied temperature d33 meter design helps to investigate the temperature dependent piezoelectric mechanism of various piezoceramics.

Corrosion tests were conducted in a high-temperature high-pressure (HTHP) autoclave to simulate the conditions of CO2 auxiliary steam drive in gas injection wells. Weight loss tests were performed with the sheets of N80 and 9Cr steels under the testing conditions. The morphology and composition of corrosion products were explored by SEM, EDS, XRD and XPS. The corrosion resistance of 9Cr steel was better than that of N80 steel under the testing conditions. The corrosion rates of N80 and 9Cr met the application requirements in CO2 auxiliary steam drive. The results broke the constraint in ISO-15156 standards. The corrosion process of N80 steel was mainly affected by the flow velocity. However, the corrosion process of 9Cr steel was mainly affected by temperature. The corrosion resistance of 9Cr steel depended on the FeCO3 content of Cr-rich layer, which was closely related to temperature. The low flow velocity influenced the diffusion process of N80 steel corrosive ions, whereas the high flow velocity influenced the integrity of corrosion scales. Considering the influence of flow velocity on the corrosion of tubing and casing, in the gas injection well, 9Cr steel and N80 steel were, respectively, selected as the materials of tubing and casing.

A copper-catalyzed asymmetric reductive allyl-allyl cross-coupling reaction of allenes with allylic phosphates wherein allenes were used as allylmetal surrogates has been achieved for the first time. This protocol provides an efficient and straightforward route to optically active 1,5-dienes in a highly enantioselective and site-specific fashion. Furthermore, all-carbon quaternary stereogenic centers could also be constructed with this protocol. The versatility of the products is demonstrated through a diverse array of further transformations of the enantioenriched 1,5-dienes.

Coauthorship prediction is challenging yet important for academic collaboration and novel research topics discovery. The challenges lie in the dynamics of social or organizational relationships, changing preferences of suitable collaborators, and the evolution of research interests or topics. However, most current approaches and systems developed so far are mainly based on past coauthorships from a static viewpoint and do not capture the above evolving characteristics in coauthoring. Accordingly, this paper proposes a time-aware approach to capture the evolving coauthorships from online academic databases in terms of capturing the dynamics of social relationships and research interests. In particular, in order to understand the underlying factors influencing researchers to make choices of coauthors, we incorporate choice modeling based on utility theory. More specifically, our model conducts a series of pairwise choices over a poset induced by a utility function so as to learn the preference over all candidate coauthors. To complete the model inference, a gradient-based algorithm is devised to efficiently learn the model parameters for large-scale data. Finally, extensive experiments conducted on a real-world dataset show that our approach consistently outperforms other state-of-the-art methods.

Based on the strong requirement for self-powered devices, energy harvesting by utilizing piezoelectric materials has recently attracted extensive attention. Transduction coefficient (d33·g33) is the core parameter of the piezoelectric energy harvesting materials, which is directly determined by the ratio of the piezoelectric charge constant (d33) to the dielectric constant (er). Unfortunately, traditional solid solution design method generally causes a simultaneous increase or decrease in both d33 and er, making it difficult to obtain a high d33·g33. In this work, a composite design strategy was proposed to separate the synergistic change of d33 and er. This was achieved by introducing lower-er ZnAl2O4 secondary phase into the popular 0.2Pb(Zn1/3Nb2/3)O3–0.8Pb(Zr1/2Ti1/2)O3 (PZN–PZT) perovskite matrix. Encouragingly, the er value rapidly decreased, while d33 value improved within a certain range compared to those of pure PZN–PZT. This was ascribed to the formation of fine domain structures in composites caused by the heterogeneous interfacial effect. Subsequently, the cantilever beam type piezoelectric energy harvesters (PEHs) made from the optimal composites exhibited a high power density of 4.0 μW mm−3 at 1 g acceleration. More importantly, PEHs could harvest vibrational energy from the operating motor to charge a capacitor and instantly drive wireless micro-sensors, demonstrating their potential application in self-powered electronics. Under the guide of the composite design strategy proposed in this work, more high performance piezoelectric energy harvesting materials can be built in the future.

This paper presents two braking regenerative energy optimization controllers for in-wheel motor electric vehicles. The first one is a velocity-tracking controller based on a model predictive control (MPC) method to recover the braking energy. It takes the front and rears in-wheel motor efficiencies into account to distribute the hydraulic and in-wheel motor braking torque of the front and rear wheels. As the vehicle information and intelligence have brought new opportunities for energy management, another velocity optimization controller is designed by considering the restricted condition of terminal distance and terminal velocity. In this strategy, a receding-horizon MPC method is proposed to solve the restricted nonlinear optimal problem. Furthermore, this optimization algorithm is transformed from the time horizon to the distance horizon to satisfy the terminal distance constraint. AMESim/Simulink co-simulations are carried out to evaluate the effectiveness of the proposed controllers. The simulation results indicate that the velocity optimization method can achieve the braking requirement as well as effectively promote regenerative efficiency.

Drug resistance arising from overexpressed efflux transporters increases the efflux of drugs and accordingly restricts the efficacy of chemotherapy. Advances in nanocarriers have provided potential strategies to cope with drug resistance. Herein, endogenous stimuli-responsive nucleus-targeted nanocarrier is developed for intracellular multidrug resistance protein 1 (MRP1) mRNA imaging and drug delivery. This nanocarrier (AuNP-mRS-DSs) is composed of three parts: (i) gold nanoparticle (AuNP), for loading DNA and quenching fluorescence; (ii) mRNA recognition sequence (mRS) modified on the surface of gold nanoparticle by gold-thiol bond, for the specific recognition of MRP1 mRNA; (iii) detachable subunit (DS), hybridized with Cy5-labeled DNA linker and nucleolin recognition motif and grafted onto mRS via the DNA linker for loading doxorubicin (Dox), binding to nucleolin, and reporting signal. First, nucleolin recognition motif of this nanocarrier targets nucleolin, which is overexpressed on cancer cells surface; subsequently, the whole nanocarrier enters the cell via nucleolin-mediated internalization. Subsequently, mRS will specifically recognize overexpressed MRP1 mRNA, leading to the release of trapped DS and followed by AuNP-quenched Cy5 fluorescence recovery. Finally, by translocation of nucleolin from cytoplasm to nucleus, the DS targets nucleus to delivery Dox. By intracellular fluorescence imaging, the differentiation of drug-resistant and nondrug-resistant cells could be achieved. Compared with free Dox (IC50 > 8.00 μM), Dox-loaded AuNP-mRS-DSs (IC50 = 2.20 μM) performed superior suppression efficacy toward drug-resistant cancer cells. Such a nanocarrier provides an effective strategy to synergistically sense and circumvent drug resistance, which may be exploited as a candidate for personalized medicine.

Investigation and evaluation of dyes play a vital role in the process of introduction novel labels and their corresponding sensing methods, which signify opportunities for the development of biosensors. This chapter introduces applications of various dyes as labels in biosensing. Bio-recognition molecules with dyes transduce biological information into measurable optical, electrochemical, magnetic or other kinds of signals for quantification. The dyes used in this field were summarized and reviewed according to their signal types, namely colorimetric, fluorescent and electrochemical. Some dyes can transduce signals between multiple physical signals. For some most important dyes, detailed descriptions were given focused on their unique properties, labeling methods and sensing mechanisms.

Ochratoxin A (OTA), a toxic secondary metabolite produced via various fungus, poses a serious threat to the health of human beings and animals. In this paper, an aptasensor for OTA detection based on gold nanoparticles decorated molybdenum oxide (AuNPs-MoOx) nanocomposites, hybridization chain reaction (HCR) and a restriction endonuclease (Nb.BbvCI)-aided walker DNA machine was successfully constructed. In this electrochemical platform, the HCR was also used to embed more electrical signal molecules of methylene blue (MB) on silver nanoparticles (AgNPs) to achieve signal amplification. Under the optimum conditions, after adding OTA and Nb.BbvCI in turn and responding adequately under appropriate conditions, aptamer-DNA (6-DNA) carries the OTA away from the electrode surface, and walker DNA was hybridized autonomously with 5-DNA, releasing a large amount of 5′-DNA with the help of Nb.BBVCI. Finally, the electrochemical signal obtained by differential pulse voltammetry (DPV) was weakened. As an artificial and popular signal amplification technique, the DNA walking machine greatly improved the sensitivity. The proposed biosensor exhibited excellent analytical performance in the range of 0.01–10000 pg mL−1 with a detection limit as low as 3.3 fg mL−1. Furthermore, direct comparison with ultraperformance liquid chromatography (UPLC) indicates excellent agreement to actual samples such as apple juice, orange juice, red wine and serum.

Background Cotton is an important fiber crop but has serious heterosis effects, and cytoplasmic male sterility (CMS) is the major cause of heterosis in plants. However, to the best of our knowledge, no studies have investigated CMS Yamian A in cotton with the genetic background of Australian wild Gossypium bickii. Conjoint transcriptomic and proteomic analysis was first performed between Yamian A and its maintainer Yamian B. Results We detected 550 differentially expressed transcript-derived fragments (TDFs) and at least 1013 proteins in anthers at various developmental stages. Forty-two TDFs and 11 differentially expressed proteins (DEPs) were annotated by analysis in the genomic databases of G. austral, G. arboreum and G. hirsutum. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed to better understand the functions of these TDFs and DEPs. Transcriptomic and proteomic results showed that UDP-glucuronosyl/UDP-glucosyltransferase, 60S ribosomal protein L13a-4-like, and glutathione S-transferase were upregulated; while heat shock protein Hsp20, ATPase, F0 complex, and subunit D were downregulated at the microspore abortion stage of Yamian A. In addition, several TDFs from the transcriptome and several DEPs from the proteome were detected and confirmed by quantitative real-time PCR as being expressed in the buds of seven different periods of development. We established the databases of differentially expressed genes and proteins between Yamian A and its maintainer Yamian B in the anthers at various developmental stages and constructed an interaction network based on the databases for a comprehensive understanding of the mechanism underlying CMS with a wild cotton genetic background. Conclusion We first analyzed the molecular mechanism of CMS Yamian A from the perspective of omics, thereby providing an experimental basis and theoretical foundation for future research attempting to analyze the abortion mechanism of new CMS with a wild Gossypium bickii background and to realize three-line matching.

Electron beam additive manufacturing (EBAM) is an emerging additive manufacturing technology with extremely high energy beam. The rapid solidification in the molten pool is of interest but not fully understood. In EBAM, with both large thermal gradient and cooling rate, the microstructure evolution during solidification is difficult to be described. The quantitative multi-phase-field model provides an effective way to reveal the dynamic evolution of dendrites in the molten pool of EBAM. In this study, the thermal profile is interpolated from the macroscale simulation at each time-step, to couple the realistic thermal evolution in the molten pool. The microstructure evolution and competitive growth have been investigated in details. Simulations of dendrite arrays with the same orientation showed how the growth velocity and the primary spacing of columnar dendrites depend on thermal gradient and cooling rate. The results are in agreement with theoretical models qualitatively. Moreover, the Gaussian nucleation model was introduced so as to give a better prediction of the microstructure in EBAM.

Different doping concentrations of Dy3+/Tm3+ in ZrF4-BaF2-YF3-AlF3 (ZBYA) fluoride glass samples were prepared by the melt-quenching method. Spectroscopic properties were analyzed through absorption (from 200 to 3300 nm) and emission spectra (from 1200 to 3200 nm). The spontaneous radiative transition probability, branching ratio and radiative lifetime of various energy levels transition were calculated based on the Judd-Ofelt theory. The emission cross-section value of the 1 mol% Dy3+/1 mol% Tm3+ co-doped ZBYA sample at 2.9 μm were calculated as 3.79×10-21 cm2. Near- and mid-IR emission spectra of Dy3+/Tm3+ co-doped ZBYA-fluoride glass under the excitation of 808 nm laser diode were investigated and discussed. Analysis of the emission spectra and the energy transition process of Dy3+/Tm3+ co-doped glass indicated that the introduction of Tm3+ ions can effectively improve the mid-infrared fluorescence intensity of Dy3+ ions, thus the Dy3+/Tm3+ co-doped ZBYA-fluoride glass can be an excellent candidate material for 2.9 μm mid-infrared laser applications.

Intense mid-infrared emission at 3.9 µm in H o 3 + -doped ZBYA glasses with direct upper laser level ( H o 3 + : 5 I 5 ) pumping at a wavelength of 888 nm is reported for the first time, to the best of our knowledge. Spectroscopic parameters were determined using the Judd–Ofelt theory and the measured absorption spectrum. The maximum emission cross section of the H o 3 + -doped ZBYA glass is estimated to be 2.7 × 10 − 21 c m 2 at 3906 nm. Additionally, fluorescence spectra and lifetimes of ZBYA glasses with different H o 3 + ion doping concentrations were measured. The results provide theoretical and experimental basis for better selection of rare-earth-doped matrix glasses to achieve a fluorescence output centered on a wavelength of 3.9 µm.

peer-reviewed The full text of this article will not be available in ULIR until the embargo expires on the 15/05/2022 In this article, a high sensitivity, low temperature-crosstalk strain sensor based on a microsphere embedded Fabry–Perot interferometer (FPI) is reported and experimentally demonstrated. The sensor is fabricated by embedding a microsphere inside a tapered hollow-core fiber (HCF) whose ends are enclosed by two standard single-mode fibers (SMFs). The reflections occurring at the SMF/HCF interface and the surfaces of the microsphere, result in a three-beam interference. The cavity length of the formed FPI can be flexibly changed by controlling the diameter of the tapered HCF and the size of the embedded microsphere, and the maximum extinction ratio (ER) of the reflection spectrum is greater than 11 dB. This novel microsphere embedded FPI structure significantly enhances the sensing performance of traditional FPIs for strain measurement, providing a high strain sensitivity of 16.2 pm/με with a resolution of 1.3 με. Moreover, it is demonstrated that this strain sensor has a very low temperature-strain cross-sensitivity of 0.086 με/oC, which greatly enhances the potential for applications in the field of precision strain measurement ACCEPTED peer-reviewed

Diachasmimoorpha longicaudata (Ashmead, D. longicaudata) (Hymenoptera: Braconidae) is a solitary species of parasitoid wasp and widely used in integrated pest management (IPM) programs as a biological control agent in order to suppress tephritid fruit flies of economic importance. Although many studies have investigated the behaviors in the detection of their hosts, little is known of the molecular information of their chemosensory system. We assembled the first transcriptome of D. longgicaudata using transcriptome sequencing and identified 162,621 unigenes for the Ashmead insects in response to fruit flies fed with different fruits (guava, mango, and carambola). We annotated these transcripts on both the gene and protein levels by aligning them to databases (e.g., NR, NT, KEGG, GO, PFAM, UniProt/SwissProt) and prediction software (e.g., SignalP, RNAMMER, TMHMM Sever). CPC2 and MIREAP were used to predict the potential noncoding RNAs and microRNAs, respectively. Based on these annotations, we found 43, 69, 60, 689, 26 and 14 transcripts encoding odorant-binding protein (OBP), chemosensory proteins (CSPs), gustatory receptor (GR), odorant receptor (OR), odorant ionotropic receptor (IR), and sensory neuron membrane protein (SNMP), respectively. Sequence analysis identified the conserved six Cys in OBP sequences and phylogenetic analysis further supported the identification of OBPs and CSPs. Furthermore, 9 OBPs, 13 CSPs, 3 GRs, 4IRs, 25 ORs, and 4 SNMPs were differentially expressed in the insects in response to fruit flies with different scents. These results support that the olfactory genes of the parasitoid wasps were specifically expressed in response to their hosts with different scents. Our findings improve our understanding of the behaviors of insects in the detection of their hosts on the molecular level. More importantly, it provides a valuable resource for D. longicaudata research and will benefit the IPM programs and other researchers in this filed.

The objective of this study was to investigate the feasibility of discriminating harvest seasons of tea by the multi‐elemental fingerprinting technique. A total of 162 tea leaf samples were collected in spring, summer and autumn of 2015 and 2016 respectively. The concentrations of 25 elements were determined by inductively coupled plasma mass spectrometry. Analysis of variance and linear discriminant analysis were performed to analyse the differences of tea leaves of different harvest seasons and years and identify the seasons and years of tea leaves. The results showed that tea leaves of different harvest seasons and years had their own elemental profiles. For tea leaves of 2015 and 2016, using the established discriminant models, the total accuracy of season‐based identification reached 95.1% and 87.7% respectively. The classifications of tea leaves of different years were 100% accurate. Therefore, the multi‐elemental fingerprinting technique can be used to identify harvest seasons of tea.

A novel series of 2-amino-2-phenylethanol derivatives were developed as β2-adrenoceptor agonists. Among them, 2-amino-3-fluoro-5-(2-hydroxy-1-(isopropylamino)ethyl)benzonitrile (compound 2f) exhibited the highest activity (EC50 = 0.25 nM) in stimulating β2-adrenoceptor-mediated cellular cAMP production with a 763.6-fold selectivity over the β1-adrenoceptor. The (S)-isomer of 2f was subsequently found to be 8.5-fold more active than the (R)-isomer. Molecular docking was performed to determine the putative binding modes of this new class of β2-adrenoceptor agonists. Taken together, these data show that compound 2f is a promising lead compound worthy of further study for the development of β2-adrenoceptor agonists.

In this research, the influence of microstructure parameters on the residual stresses of ultrafine-grained sheets was investigated. For this purpose, the constrained groove pressing (CGP) process was carried out on the copper sheets with 3 mm thickness, and residual stresses of the CGPed sheets was measured using the contour method. Microstructure of the CGPed specimens was evaluated by the optical microscopy, micro x-ray diffraction (micro-XRD), and transmission electron microscopy (TEM) experiments. Microstructure parameters including crystallites size, dislocations density, and lattice strain were calculated using Williamson-Hall and Williamson-Smallman equations, and the calculated results were validated by the TEM images. The influence of these parameters on the residual stresses was investigated by analysis of variance (ANOVA) method, and two approaches were considered in this way. According to the results, the CGP process can create nanostructures in the CGPed sheets, and with increasing number of CGP passes, grains size, crystallites size, lattice strain, and residual stresses decrease, and density of dislocations increases. Microstructure parameters have a significant effect on the macro-residual stresses, and strain is the most effective parameter. Also, in the ultrafine-grained sheets, micro-parameters have an undeniable contribution, which is the same as that of macro-parameters on the macro-residual stresses.

A novel and efficient ultra-high performance supercritical fluid chromatography method was developed for the quantitative analysis of five retinol isomers in animal livers. The separation of the five retinol isomers was carried out using an Acquity UPC2 HSS C18 SB column (150 mm × 3.0 mm, 1.8 µm) with acetonitrile as a co-solvent. By optimizing the columns, gradient program, co-solvent, column temperature and backpressure, the five retinol isomers and the internal standard 11-cis-13,14-dihydroretinol were successfully separated within 20 min. Samples were saponified and extracted by solid-supported liquid–liquid extraction using a diatomaceous earth cartridge. Comparing with the traditional liquid–liquid extraction, the extraction enables the reduction of time-consuming and laborious procedures. This method used 11-cis-13,14-dihydroretinol as an internal standard to improve the precision and accuracy of quantitative analysis. The correlation coefficients (r2) of the calibration curves were all above 0.999, the limits of detection for the five retinol isomers were in the range of 0.10–0.20 µg mL− 1, and the limits of quantification were in the range of 0.33–0.66 µg mL− 1. The mean recoveries were from 92.5 to 102.5%. The interday and intraday relative standard deviations were within 10%. This method was successfully applied to the determination of retinol isomers in ten raw animal livers and animal liver products (chicken, duck, pig, cattle, and sheep).

Graphene has been demonstrated to have enormous potential applications. The realization of the applications is closely related to the fabrication of graphene nanostructures. In this paper, the recent studies of graphene nanostructure fabrication by particle beam (laser beam, electron beam and ion beam) irradiation have been reviewed, for which the usage of atomic simulation methods is focused on. Firstly, the interaction mechanism between particle beam and graphene is discussed. Then based on the different interaction mechanisms, the atomic simulation models were built to figure out the feasibility of using particle beam irradiation to dope graphene, join graphene and fabricate graphene nanopore. The limitations of the present models are analyzed at last, and the possible future research directions are forecasted. This review aims at stimulating further research on this subject.

The twinning and slip modes of a rolled magnesium alloy sheet were investigated through quasi-in-situ tensile tests that were carried out along the rolling direction at room temperature with a constant strain rate. Scanning electron microscopy and electron backscattered diffraction observations were used to identify activated twinning and slip systems. Schmid factors were calculated to analyze different deformation modes. The analyses show that a small number of {10-12} tensile twins were present during deformation, and these twins resulted from the accommodation of compression along the tensile direction. Post-deformation examination revealed the dominance of prismatic slip.

The architecture and quality of lacustrine turbidites that act as petroleum reservoirs are less well documented. Reservoir architecture and multiscale heterogeneity in turbidites represent serious challenges to production performance. Additionally, establishing a hierarchy profile to delineate heterogeneity is a challenging task in lacustrine turbidite deposits. Here, we report on the turbidites in the middle third member of the Eocene Shahejie Formation (Es3), which was deposited during extensive Middle to Late Eocene rifting in the Dongying Depression. Seismic records, wireline log responses, and core observations were integrated to describe the reservoir heterogeneity by delineating the architectural elements, sequence stratigraphic framework and lithofacies assemblage. A petrographic approach was adopted to constrain microscopic heterogeneity using an optical microscope, routine core analyses and X-ray diffraction (XRD) analyses. The Es3m member is interpreted as a sequence set composed of four composite sequences: CS1, CS2, CS3 and CS4. A total of forty-five sequences were identified within these four composite sequences. Sand bodies were mainly deposited as channels, levees, overbank splays, lobes and lobe fringes. The combination of fining-upward and coarsening-upward lithofacies patterns in the architectural elements produces highly complex composite flow units. Microscopic heterogeneity is produced by diagenetic alteration processes (i.e., feldspar dissolution, authigenic clay formation and quartz cementation). The widespread kaolinization of feldspar and mobilization of materials enhanced the quality of the reservoir by producing secondary enlarged pores. In contrast, the formation of pore-filling authigenic illite and illite/smectite clays reduced its permeability. Recovery rates are higher in the axial areas and smaller in the marginal areas of architectural elements. This study represents a significant insight into the reservoir architecture and heterogeneity of lacustrine turbidites, and the understanding of compartmentalization and distribution of high-quality sand reservoirs can be applied to improve primary and secondary production in these fields.

Because of their perfect geometrical symmetry, spherical metal nanoparticles have attracted much attention for various applications, including fundamental studies and construction of plasmonic devices. In this work, monodisperse silver nanospheres (Ag NSs) in aqueous solution were directly prepared by a continuous process of seed-mediated growth followed by oxidative etching. Silver nanocubes (Ag NCs) were synthesized by a seed-mediated growth method and subsequently were transformed to Ag NSs by simple injection of Cu2+ to the freshly prepared Ag NCs solution. Not requiring any centrifugation steps at both growth and etching stages makes this procedure convenient and efficient. The etching process and morphology evolution of silver nanostructure were monitored by UV–vis spectromater, SEM, and XRD. Monodisperse Ag NSs with broadly tunable diameters (from 37 to 68 nm) have been successfully prepared. The optical property of Ag NSs has been studied and the experimental results show fairly good consistency w...

To assess the relationship between metal ion-mediated microstructures and the macro-performance, Cu- and Zn-doped α-Fe2O3 nanoparticles were prepared via a solvothermal method. The morphologies of the as-synthesized nanoparticles were investigated by scanning electron microscopy and transmission electron microscopy. The results revealed that the sizes and morphologies could be regulated by doping with divalent cations. The structures of the as-synthesized nanoparticles were characterized by X-ray diffraction and Raman spectroscopy, indicating that Cu2+ and Zn2+ ions had diffused into the lattice of α-Fe2O3 matrix. The magnetization behaviors of these nanoparticles were measured to analyze the effect of doping on α-Fe2O3. Furthermore, the catalytic activities of Cu- and Zn-doped α-Fe2O3 nanoparticles demonstrated that the high-temperature decomposition temperature of ammonium perchlorate could be lowered by 115 °C and 107 °C, respectively, compared to that of ammonium perchlorate without catalyst. The enhanced catalytic activity could be attributed to the defect structure induced by doping with divalent cations.

Inulinases from microorganisms have been extensively studied for their role in the production of fructose from fructan. Fructan can also be hydrolyzed by plant fructan exohydrolases (FEHs), but these enzymes have not been used to produce fructose commercially. Two Ht1-FEHs (Ht1-FEH I and Ht1-FEH II) were recently characterized in Jerusalem artichoke. In this study, we cloned the third member of the Ht1-FEH family in Jerusalem artichoke (i.e., Ht1-FEH III). When heterologously expressed in Pichia pastoris X-33, Ht1-FEH III not only demonstrated hydrolysis activity towards β (2, 1)-linked fructans and β (2, 6)-linked levan, but also towards sucrose. To explore the potential industrial applications, we heterologously expressed and purified six plant 1-FEHs from two typical fructan plants (i.e., chicory and Jerusalem artichoke) and showed that chicory Ci1-FEH IIa had the highest hydrolysis capacity to fructan in vitro. Furthermore, we immobilized Ci1-FEH IIa on resin and optimized the immobilization conditions. We found that inulin-type fructan or the tuber extract from Jerusalem artichoke could be rapidly degraded into fructose and sucrose by immobilized Ci1-FEH IIa. The capacity of Ci1-FEH IIa to release fructose from fructans was comparable to that of some inulinases from microorganisms. Thus, plant FEHs have potential applications in fructose production.

Three new organic–inorganic hybrid di‑copper-complex substituted monovacant polyoxotungstates, [{Cu I 3 (phen)} 3 Cl 2 ]{[Cu II (phen) 2 ][Cu II 2 (phen)]} 2 ( α -PW 11 O 39 ) ( 1 ), Na[Cu II 2 (bpy) 2 (OH) 2 ][Cu II 2 (bpy) 2 (H 2 O)( α -PW 11 O 39 )]·3H 2 O ( 2 ) and [Cu II (bpy)(H 2 O)][Cu II 2 (bpy) 2 (H 2 O)( α -HPW 11 O 39 )]·H 2 O ( 3 ) (phen = 1,10-phenanthroline; bpy = 2,2′-bipyridine), have been made under hydrothermal conditions and characterized by elemental analyses, IR spectra, XRD, thermogravimetric (TG) analyses and X-ray single-crystal diffraction. The compounds 1 – 3 are isostructural and all containing di‑copper-complex substituted monovacant phosphotungstate subunits as well as different pendant copper cations. Compound 1 represents the first discrete di‑copper-phen complex substituted monovacant Keggin polyoxotungstate. For compound 2 , it can be regarded as a dimmer of two di‑copper-bpy substituted {[Cu II 2 (bpy) 2 (OH)][Cu II 2 (bpy) 2 (H 2 O)( α -PW 11 O 39 )]} clusters that were connected by two μ-OH groups. Compound 3 is the rare di‑copper-bpy substituted monovacant Keggin phosphotungstate with 1D dual-bridging chain structure. Furthermore, the variable-temperature magnetic susceptibility of 1 has been investigated in detail.

Large-scale ordered two-dimensional (2D) superlattices at oil/water interface were fabricated using single-crystal Au nanospheres (NSs) with different diameters as building blocks. A “drain-to-deposit” strategy was used to successfully transfer the ordered superlattices onto silicon wafer. Due to the ultra-smooth and highly spherical morphology of the monodisperse Au NSs, the UV-Vis extinction spectra of individual Au nanosphere (NS) obtained from theoretical calculations by finite-difference time-domain (FDTD) method could match well with the experimental test results. Moreover, the extinction spectra of the 2D superlattice based on the different diameters of Au NSs were also measured and calculated. Additionally, with R6G as probe molecules, the surface-enhanced Raman spectroscopy (SERS) performances of the prepared superlattices were evaluated. Through investigating the electromagnetic (EM) field distribution simulation results of 2D superlattices of Au NSs with different diameters, the two results reveal rather consistently. The large-scale 2D plasmonic superlattices possess precise and tunable localized surface plasmon resonance (LSPR) property, which enables them to have great application prospect in solar cells, SERS detection, and other fields.