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An ultrahigh sensitivity surface plasmon resonance sensor based on double-side polished photonic crystal fiber is designed, and the gold film with a zigzag cross section is used as the plasmonic material. We study the refractive index sensing characteristics of the proposed sensor by numerical simulation. The results show that compared with the flat gold film structure, the zigzag gold film structure effectively improves the sensing performance, and the sensitivity and resolution of the sensor are significantly enhanced. The maximum wavelength sensitivity and resolution of the proposed sensor can reach 20,000 nm/RIU and 5.00 × 10−6 RIU, respectively. The working wavelength range of the sensor is between 590 and 1200 nm, and the refractive index range that can be used for detection is 1.350 RIU-1.400 RIU. This can be applied to precise detection of extracellular vesicles, breast cancer cell, and red blood cells. The proposed sensor has significant advantages such as stable structure, ultrahigh sensitivity, fast response, small size, and saving noble metal. It has great application potential in biomedical testing and medical equipment. [ABSTRACT FROM AUTHOR]

Advanced metering infrastructure (AMI) is a fundamental functional module of Smart Grid that supports mutual communication between customers and electric companies. In order to secure AMI communication, scholars have proposed many key management schemes, some of which suffer from security issues or high costs. Recently, Mohammadali et al. proposed a key establishment NIKE protocol based on Elliptic Curve Cryptography. In this paper, we demonstrate that the protocol is vulnerable to both replay and tampering attacks and does not provide user anonymity. For the security vulnerabilities of the NIKE protocol, we propose an improvement scheme. And the proposed scheme is analyzed and verified for security based on the random oracle model and formal tools. Finally, we perform performance analysis of the improved scheme and the results show that the scheme has low communication and computation costs. [ABSTRACT FROM AUTHOR]

Quantum communication scheme can play an important role in quantum teleportation. In this paper, an improved asymmetric scheme for bidirectional controlled quantum teleportation of special three-qubit entangled state by using the nine-qubit entangled state as a quantum channel is presented theoretically. In this scheme, two distant parties, Annie and Ben, are both senders and receivers. While Annie wants to send a special three-qubit entangled state to Ben, Ben wishes to transmit another special three-qubit entangled state back to Annie. This scheme only requires the Von Neumann type measurements, controlled-not (CNOT) operations and appropriate unitary operations. By introducing the appropriate unitary transformation and auxiliary particles, Annie and Ben may reconstruct the initial state to achieve quantum teleportation successfully. [ABSTRACT FROM AUTHOR]

We propose and demonstrate a compact optical fiber temperature sensor based on surface plasmon resonance with high sensitivity and high figure of merit. This optical fiber temperature sensor uses a new photonic crystal fiber designed by us, which is realized by coating a gold film on the polished plane of the photonic crystal fiber and coating the high thermo-optical coefficient material polydimethylsiloxane on the outer surface of the fiber. Small changes in the refractive index of the polydimethylsiloxane due to temperature variations will affect the plasmon pattern, which in turn leads to a change in the measured transmission spectrum. Our numerical results show that the maximum achievable temperature sensitivity of this optical fiber temperature sensor in the range of 60–100 °C is 38 nm/°C, and the maximum refractive index sensitivity and figure of merit are 84444.4 nm/RIU and 603.175 RIU−1, respectively. This is better than the existing various types of PCF temperature sensor. The proposed temperature sensor has the advantages of stable structure, ultra-high temperature sensitivity, and small size. It has good application potential in the field of high-precision temperature control, environmental temperature detecting. [ABSTRACT FROM AUTHOR]

Ga2O3 is clearly emerging as an important wide band‐gap semiconductor. Band‐gap engineering is now highly demanded for expanding its applications. Alloying with the same group of metal oxides is a straightforward and effective way. In this work, by using hybrid density functional theory calculations, the structural, electronic properties, and phase stability of group IIIA (Al, Ga, In) metal oxides and their ternary alloys (MxGa1‐x)2O3 (M = Al, In) in the corundum and monoclinic phases are systematically investigated. The lattice constants, elastic constants, modulus, formation energies, band‐gaps, band‐gap deformation potentials, band‐edge alignments, band‐gap bowing, and ternary alloy formation energies are obtained. The basic relations between the geometric structure and electronic properties are discussed. It is found that the cation ordered structure is the most stable alloy structure in the monoclinic phase, rather than the random alloy structure as is commonly thought. A phase stability diagram of the (MxGa1‐x)2O3 alloys is established, showing that the stable phase of the alloy changes from the monoclinic phase to the corundum phase when the incorporation of Al2O3 (In2O3) is greater than 69% (76%). These results can be used to understand the relative experimental data and shed some light on the synthesis and device design efforts of Ga2O3. [ABSTRACT FROM AUTHOR]

We have investigated the wurtzite (10 1 ¯ 1) planes of five semiconductors, AlN, GaN, GaAs, ZnO, and ZnS. The absolute surface energies are obtained by using a series of wedge nanowire structures. A cation-adsorbed surface reconstruction, (1 × 1)X (X is the electropositive element of the semiconductor) adlayer, is found to have dramatically low energy under the cation-rich condition for AlN and GaN. A p electron draining mechanism is proposed to explain these results. We also developed a framework to analyze the stabilization mechanism of the unneutral surfaces. It suggests that the cation-adsorbed surfaces of II–VI semiconductors should be more unstable than the anion-adsorbed surfaces. [ABSTRACT FROM AUTHOR]

Abstract An improved wedge-shape method is employed to calculate the absolute surface energies of wurtzite ZnO high index polar surfaces. From the viewpoints of atomic structure and surface energy, the stabilization mechanism of high index polar surfaces is systematically investigated. Under different conditions (O and Zn rich), the stable surface structures are discussed, and it is found that some high index polar surfaces may have lower surface energy than conventional (10 1 ¯ 0) or (0001) surfaces. This may be of vital importance to the surface morphology of nanostructures. In addition, the calculation results are well in agreement with experimental observations. The present theoretical and experimental work can provide important insights to the growth and surface treatment of complex nanostructures. Graphical abstract Image 1 Highlights • An improved method is proposed for calculation of absolute surface energy. • The stabilization mechanism of high index polar surfaces is investigated. • Experimental observations are explained very well by the calculated results. [ABSTRACT FROM AUTHOR]

We experimentally demonstrate a convenient approach to fabricate large area photorefractive photonic microstructures by a spliced lens device. Large area two-dimensional photonic microstructures are optically induced inside an iron-doped lithium niobate crystal. The experimental setups of our method are relatively compact and stable without complex alignment devices. It can be operated in almost any optical laboratories. We analyze the induced triangular lattice microstructures by plane wave guiding, far-field diffraction pattern imaging and Brillouin-zone spectroscopy. By designing the spliced lens appropriately, the method can be easily extended to fabricate other complex large area photonic microstructures, such as quasicrystal microstructures. Induced photonic microstructures can be fixed or erased and re-recorded in the photorefractive crystal. [ABSTRACT FROM AUTHOR]

In a first principles study of the formaldehyde adsorption on ZnO surface, we found a novel chain adsorption structure on ZnO ( 10 1 ¯ 0 ) plane. This adsorption structure results from the electrostatic interactions between those adsorbed formaldehyde molecules and the unique arrangement of Zn-O surface dimers on ( 10 1 ¯ 0 ) plane. This adsorption mechanism has the potential to extend to other wurtzite materials’ ( 10 1 ¯ 0 ) plane and other similar cases. As the physical adsorption configurations are unstable, the chemical adsorption has to happen. The electronic properties show that the C O double bond in CH 2 O turns into C O single bond and the highest occupied molecule orbital (HOMO) of formaldehyde is lifted into ZnO band gap becoming the hole trapping center. These results may be meaningful for formaldehyde degradation and detection. [ABSTRACT FROM AUTHOR]

• The combinative energy between the perovskite block and the rock-salt block in the codoped Y1-xCaxBa2-yLayCu3Oz system is calculated according to the "block model". • A new parameter γ describing the combined effects of the combinative energy (lattice degree of freedom) and the charge carrier density (charge degree of freedom) is defined. • The tendency of γ changing with doping is well consistent with that of the superconducting transition temperature (Tc) over the whole doping range, suggesting the important roles of both the lattice and charge degrees of freedom in influencing the unconventional superconductivity. Polycrystalline samples of Y 1- x Ca x Ba 2- y La y Cu 3 O z cuprate superconductors with both x and y ranging from 0 to 0.5 were investigated. The combinative energy between the perovskite block and the rock-salt block in this codoped system was calculated according to a previously proposed "block model". By defining a new parameter γ describing the combined effects of the combinative energy (lattice degree of freedom) and the charge carrier density (charge degree of freedom), it is revealed that the tendency of γ changing with doping is well consistent with that of the superconducting transition temperature (T c) over the whole doping range, suggesting the important roles of both the lattice and charge degrees of freedom in influencing the unconventional superconductivity. [ABSTRACT FROM AUTHOR]

A convenient approach to fabricate area scalable two-dimensional photonic microstructures was experimentally demonstrated by multi-face optical wedges. The approach is quite compact and stable without complex optical alignment equipment. Large-area square lattice microstructures are optically induced inside an iron-doped lithium niobate photorefractive crystal. The induced large-area microstructures are analyzed and verified by plane wave guiding, Brillouin-zone spectroscopy, angle-dependent transmission spectrum, and lateral Bragg reflection patterns. The method can be easily extended to generate other more complex area scalable photonic microstructures, such as quasicrystal lattices, by designing the multi-face optical wedge appropriately. The induced area scalable photonic microstructures can be fixed or erased even re-recorded in the photorefractive crystal, which suggests potential applications in micro-nano photonic devices. [ABSTRACT FROM AUTHOR]

We experimentally demonstrate a convenient approach to fabricate two-dimensional periodic photonic lattices and quasicrystal microstructures in iron-doped lithium niobate photorefractive crystal by multi-lens board. The method does not require complicated optical adjustment system. We analyze the induced square photonic lattices, elliptic photonic lattices and quasicrystal microstructures by plane wave guiding, far-field diffraction pattern imaging and Brillouin-zone spectroscopy. Induced photonic microstructures can be fixed or erased and re-recorded in the crystal. We also numerically demonstrate that the method can be easily extended to form other complex photonic microstructures by designing the multi-lens board appropriately. [ABSTRACT FROM AUTHOR]

We fabricate several different photonic lattice microstructures in iron-doped lithium niobate photorefractive crystal using single step projection method by a spatial light modulator. Wavy photonic lattice and several lattice structures with different defects were one-step induced inside the crystal. This method makes up the weakness of the conventional multiple beams interference method. The experimental setup is very flexible and easy to operate without complicated programming. Induced photonic structures can be fixed or erased and re-recorded in the crystal. The method can be easily extended to fabricate diverse photonic microstructures by drawing different structural patterns on a computer. [ABSTRACT FROM AUTHOR]

A convenient approach to generate two-dimensional photorefractive photonic heterostructures with composite periods was experimentally demonstrated by multi-lens boards. The approach is pretty simple and does not require any complicated optical adjustment as the conventional methods did. Two kinds of composite periodic lattice structures are numerically simulated and optically induced inside an iron-doped lithium niobate photorefractive crystal. The induced composite photonic microstructures can be fixed or erased even re-recorded in the photorefractive crystal, which suggests potential applications in nonlinear photonic devices. Numerical simulation illustrates that the method can be easily extended to form more complex photonic microstructures by designing the multi-lens board appropriately. [ABSTRACT FROM AUTHOR]

Abstract: Three-dimensional Penrose-type photonic quasicrystal lattices are optically induced inside an iron-doped lithium niobate photorefractive crystal for the first time using a single multi-pinhole plate. The setup of this method is simple and compact dispense with complex optical adjustment system. Induced Penrose-type photonic quasicrystal lattices are analyzed and verified by plane wave guiding and far field diffraction pattern imaging. The quasicrystal microstructures can be maintained for a long time inside the crystal in a dark room. Other more complex three-dimensional photonic quasicrystal structures can be fabricated with this method by designing the multi-pinhole plate flexibly. [Copyright &y& Elsevier]

We fabricate two-dimensional elliptic photonic lattices in iron-doped lithium niobate photorefractive crystal for the first time with optical induction method. The experimental setup of our method is very simple and flexible without complicated optical adjustment system. We analyze and verify the two-dimensional elliptic photonic lattices by plane wave guiding, far field diffraction pattern imaging, and Brillouin-zone spectroscopy. Induced elliptic photonic lattices can stably exist for a long time in the iron-doped lithium niobate crystal. The induced two-dimensional elliptic photonic lattices might offer an easy method to study generic band gap phenomena in anisotropic periodic structures. [ABSTRACT FROM AUTHOR]

Linear propagation behavior of light wave in two-dimensional ten-fold symmetric photonic quasicrystal lattices was studied numerically by using beam propagation method. The influences of structural characteristics and parameter changes of the quasicrystal lattices on the propagation and suppression of light wave diffraction are analyzed, and the results are also compared with those in periodic square lattices. We investigate the linear transverse light localization in the quasicrystal lattices without defects. The results indicate that the quasicrystal lattices are easier to achieve linear light localization than the periodic lattices. In addition, we demonstrate the distortionless transmission of light-spot images can be achieved in the quasicrystal lattices by numerical simulation. In this way, more complex light-spot images can be transmitted in photonic quasicrystal arrays which are consisting of multiple basic units of quasicrystal lattices. It has potential applications for optical information transmission and all optical signal processing. • Diffraction propagation of light wave in photonic quasicrystal is investigated. • Transverse light localization in photonic quasicrystal is realized by simulation. • Light-spot images can be transmitted without distortion in the quasicrystal arrays. • It has potential applications in optical information transmission. [ABSTRACT FROM AUTHOR]

Abstract: We demonstrate an approach for easy fabrication of large area two-dimensional nonlinear photonic lattices in photorefractive crystal using the laser interference technique with an improved Michelson interferometer. The experimental setup of this method is relatively simple and inexpensive. It can be applied in almost any optical laboratories. Large area (about 28.2mm2) two-dimensional square nonlinear photonic lattices have been produced in an iron-doped lithium niobate photorefractive crystal. We analyze the induced nonlinear photonic lattices by plane wave guiding, Brillouin-zone spectroscopy and far field diffraction pattern imaging. The period of the induced photonic lattices can be dominated easily. The induced photonic lattices can exist stably for a long time in the photorefractive crystal. [Copyright &y& Elsevier]

We fabricate two-dimensional photonic quasicrystal lattices in iron-doped lithium niobate photorefractive crystal by a single amplitude mask. The experimental setup of this method is very simple and flexible without complicated optical adjustment system. It can be applied in almost any optical laboratories. We analyze the photonic quasicrystal lattices by plane wave guiding, Brillouin-zone spectroscopy and far field diffraction pattern imaging. The induced photonic quasicrystal lattices can exist stably for a long time in the photorefractive crystal. This method can be easily extended to generate more complex quasi-periodicity microstructures by designing the amplitude mask properly. [ABSTRACT FROM AUTHOR]

Abstract: We demonstrate an approach for easy fabrication of two- and three-dimensional optically induced nonlinear photonic lattices microstructures in photorefractive crystal by applying spatial filter and amplitude mask. The experimental setup of this method is very simple and flexible without complicated optical adjustment system. It can be applied in almost any optical laboratories. Two-dimensional hexagonal, square and three-dimensional hexagonal nonlinear photonic lattices microstructures have been produced in an iron-doped lithium niobate photorefractive crystal. The period of the induced photonic lattices microstructures can be dominated easily. This method is easily extended to generate more complex photonic lattices microstructures in photorefractive crystals, such as quasicrystal lattice. [Copyright &y& Elsevier]

Abstract: We fabricate three-dimensional nonlinear photonic lattices in iron-doped lithium niobate photorefractive crystal for the first time by a single amplitude mask. The experimental setup of this method is very simple and flexible. The period of the lattices can be dominated easily. We analyze the three-dimensional photonic lattices by plane wave guiding and far field diffraction pattern imaging. The induced photonic lattices can exist stably for a long time in the photorefractive crystal. [Copyright &y& Elsevier]

Abstract: We fabricate three-dimensional nonlinear photonic lattices in self-defocusing iron-doped lithium niobate photorefractive crystal for the first time by an improved Michelson interferometer device. The experimental setup is simple and inexpensive. The period of the induced photonic lattices can be dominated easily. We analyze the three-dimensional nonlinear photonic lattices by plane wave guiding and far field diffraction pattern imaging. The induced nonlinear photonic lattices can exist stably for a long time in the photorefractive crystal. [Copyright &y& Elsevier]

• We fabricate three kinds of periodic microstructures in LiNbO 3 :Fe crystal. • The experimental setup does not need complicated optical alignment components. • The method can adjust the polarization and phase delay of interference beams. • Induced microstructures are analyzed and validated by diverse methods. • Other more complex photonic microstructures can be fabricated with this method. We experimentally demonstrate a convenient method to fabricate two-dimensional photonic microstructures in photorefractive crystal. Three kinds of photonic microstructures have been fabricated in iron-doped lithium niobate crystal using six wedge prisms array. The experimental setup of our method does not require complicated optical alignment components. Induced two-dimensional triangular lattice photonic microstructures are analyzed and validated by plane wave guiding, far-field diffraction pattern imaging, Brillouin-zone spectroscopy, and angle-dependent transmission spectrum. The method can be easily extended to fabricate other complex photonic microstructures by designing different wedge prisms array and adjusting polarization and phase delay properly. [ABSTRACT FROM AUTHOR]

• Innovative use of dual laser beam welding to solve porosity defects. • Optimization of welding parameters using BPNN algorithm and Taguchi experiment. • Yield strength optimized is significantly higher which is due to defect-free weld. Gas porosity is very critical factor to affect the welding performance and mechanical properties of weld bead. Dual laser beam welding, as a new laser welding process, is helpful to reduce the porosity number in weld bead because of several advantages like enlarging the molten pool, increasing the fluid speed, stabling the keyhole geometry. However, dual laser beam welding requires consideration of more parameters (beam spacing, energy distribution ratio) than single laser beam welding. To optimize dual beam welding process, a 16 groups Taguchi approach together with artificial neural networks (ANN) and genetic algorithm (GA) has been applied to obtain the best welding parameters of laser beam welding for 316L austenite stainless steel during dual beam laser beam welding. X-ray detection results are regarded as the basis for evaluation of porosity number and welding quality. After optimizing, the porosity number is significantly decreased compared to original weld bead. The comparison of microstructure, and yield strength between original parameters and optimized one is carried out to verify optimal results. [ABSTRACT FROM AUTHOR]

We have experimentally demonstrated a convenient method to fabricate area-controllable photonic quasicrystals in a photorefractive crystal. Two-dimensional eight-fold symmetric quasicrystal microstructures have been fabricated by using a diffractive optical element and Fourier transform lens system. The experimental devices of this method do not need complex optical alignment elements, and the area of induced quasicrystal microstructures can be adjusted flexibly. Induced eight-fold symmetric quasicrystal microstructures are observed and validated by guided wave intensity pattern and far-field diffraction pattern imaging. Induced quasicrystal microstructures can be permanently fixed in the crystal or erased by white light flushing according to different requirements. • We fabricate area-controllable photonic quasicrystals by a convenient method. • Eight-fold symmetric photonic quasicrystals have been induced in LiNbO 3 :Fe crystal. • The area of induced quasicrystal microstructures can be adjusted flexibly. • The experimental setup does not need complex optical alignment elements. • Induced photonic quasicrystals are observed and validated by diverse methods. [ABSTRACT FROM AUTHOR]

• A real-time harmonics detection method based on input observer is proposed. • Solving the problem of harmonics detection error caused by frequency fluctuation. • This method shall not be affected by the circuit topology. In this paper, a real-time detection method based on input observer is introduced for harmonics extraction of the grid currents in the case of fundamental frequency fluctuation. The proposed method has the advantages of fast detection speed and high detection precision, and can deal with the sudden changes in grid currents amplitudes and fundamental frequency. It works as follows: first of all, a phase-locked loop is used to extract the phase of grid currents in real-time. Then a state space model is constructed with grid currents and the harmonic components as unknown state variables. Finally, with the detected real-time phase, a linear time-varying observer based on the state space model is designed to estimate the unknown state variables. Its stability is guaranteed by Lyapunov function and LaSalle's Invariance Principle. Thus the extraction of grid currents harmonics is realized. Both simulation and experimental results show that the harmonic components of grid currents can be quickly and accurately extracted by proposed method even if the grid currents are distorted. [ABSTRACT FROM AUTHOR]

The density functional theory method study is performed to investigate the adsorption structures and mechanisms of water adsorption on ZnO high index polar surfaces. It is found that compared to the nonpolar 10 1 ¯ 0 and (0001) surfaces, high index polar surfaces present higher ability to adsorb water molecules. The dissociative adsorption configurations are energetically more favorable than the molecular adsorption ones, i.e., the adsorbed water molecule would like to decompose into a hydroxyl group and a H atom on high index polar surfaces. The structural calculations and electronic properties suggest that the electron counting rule plays an important role in determining the energetically favorable configurations. This detailed and systematic work not only improves our understanding of the water adsorption on high index polar surfaces, but also it may ultimately aid the applications of nanostructures coated by high index polar surfaces. Unlabelled Image • Water adsorption on ZnO high index polar surfaces is systematically investigated. • Dissociative adsorptions are more energetically favorable than molecular adsorptions. • The electron counting rule is found to play a crucial role in determining the adsorption configuration. [ABSTRACT FROM AUTHOR]

In this research, a grid voltage sensorless control scheme under the distorted grid voltage condition for a single-phase rectifier was proposed. For eliminating the grid voltage sensor, a time-varying state observer was designed, which provided direct, accurate, and fast estimation of the grid voltage without subsequent complex calculations, even for the presence of harmonics, a DC component, and frequency fluctuations, and it was implemented in the digital processor through Forward Euler discretization. In addition, the aforementioned observer would be partially reused in another observer to modify the input of the PI controller and then reduce the total harmonic distortion of the input current. To warrant robustness for the real world, the proposed observers were investigated in detail for load resistance variations and grid voltage fluctuations. Several simulations and experimentation tests were conducted to verify the effectiveness of proposed scheme. The obtained results indicated that the proposed observers had fast dynamic responses and low estimation errors. The proposed scheme decreased the THD of the input current. [ABSTRACT FROM AUTHOR]

Highly efficient blue quantum‐dot light‐emitting diodes (QLEDs) are still a challenge for displays and solid‐state lighting due to light trapping in a device. Herein, an internal diffraction wrinkle pattern is used to demonstrate a spectrum‐independent enhancement strategy for light out‐coupling. The optimized device with wrinkle pattern shows a peak external quantum efficiency of 15.25% and a maximum luminance of 13 134 cd m−2, and the enhancement of those is 23% and 28%, respectively. The improvement of device performance can be attributed to the extraction of waveguide light by the internal wrinkle pattern used as a diffraction grating. Moreover, simulation also shows that wrinkle pattern is an attractive option to improve the performances of blue QLEDs. [ABSTRACT FROM AUTHOR]

Zinc finger protein (ZFP) transcription factors play a pivotal role in regulating plant growth, development, and response to biotic and abiotic stresses. Although extensively characterized in model organisms, these genes have yet to be reported in bamboo plants, and their expression information is lacking. Therefore, we identified 21 B-box (BBX) genes from a transcriptome analysis of Bambusa pervariabilis × Dendrocalamopsis grandis. Consequently, multiple sequence alignments and an analysis of conserved motifs showed that they all had highly similar structures. The BBX genes were divided into four subgroups according to their phylogenetic relationships and conserved domains. A GO analysis predicted multiple functions of the BBX genes in photomorphogenesis, metabolic processes, and biological regulation. We assessed the expression profiles of 21 BBX genes via qRT-PCR under different adversity conditions. Among them, eight genes were significantly up-regulated under water deficit stress (BBX4, BBX10, BBX11, BBX14, BBX15, BBX16, BBX17, and BBX21), nine under salt stress (BBX2, BBX3, BBX7, BBX9, BBX10, BBX12, BBX15, BBX16, and BBX21), twelve under cold stress (BBX1, BBX2, BBX4, BBX7, BBX10, BBX12, BBX14, BBX15, BBX17, BBX18, BBX19, and BBX21), and twelve under pathogen infestation stress (BBX1, BBX2, BBX4, BBX7, BBX10, BBX12, BBX14, BBX15, BBX17, BBX18, BBX19, and BBX21). Three genes (BBX10, BBX15, and BBX21) were significantly up-regulated under both biotic and abiotic stresses. These results suggest that the BBX gene family is integral to plant growth, development, and response to multivariate stresses. In conclusion, we have comprehensively analyzed the BDBBX genes under various adversity stress conditions, thus providing valuable information for further functional studies of this gene family. [ABSTRACT FROM AUTHOR]

The quantum spin liquid (QSL) states with no long-range magnetic order even down to zero temperature have recently raised intensive research interest. Here we propose that the spin frustration characteristic of the QSL candidates also make them superior magnetocaloric materials that exhibit prominent cooling effect, especially near the quantum critical points. By simulating the highly frustrated kagome and triangular lattice models, we reveal a significant magnetothermal pumping effect when combing quantum magnets with paramagnetic salts, which can be exploited to design a high-performance cascade demagnetization refrigerator. Moreover, with realistic magnetic compounds YbAlO3 and Na2BaCo(PO4)2, we find a giant enhancement in the cooling capacity characterized by a great increment rate, e.g., more than 200% when working between 3 K heat sink and 30 mK load. Our work thus paves a promising and viable way for the quantum spin cooling to promote the helium-free refrigeration useful in space applications and quantum technologies. Quantum spin liquids are a series of materials which exhibit an absence of magnetic order down to absolute zero and may have applications for data storage and memory. Here, using numerical simulations, the authors propose that the magnetic frustration in a quantum spin liquid may also lead to pronounced magnetocaloric effects near the quantum critical point with potential application as materials for refrigerants. [ABSTRACT FROM AUTHOR]

Abstract: Novel semisynthetic analogs of salvinorin A, a full agonist having extraordinary affinity as well as selectivity for the κ-opioid receptor (KOR), were obtained in good yields. The derivatives are remarkable for their unusual and unique hemiacetal structure in the salvinorin series of compounds. The formation of the hemiacetal occurs with epimerization at C-12, thus preserving the original configuration of salvinorin A. The dimethyl ester derivative of the hemiacetal was found to have an affinity for both KOR and MOR (μ-opioid receptor). [Copyright &y& Elsevier]

Using a facile hydrothermal method, we have successfully synthesized carbon doped (C-doped) ZnO nanorods with standard hexagonal column shapes. To modify their photocatalytic activities by tailoring the surfaces, a post etching process under ammonia atmosphere was used, and these nanorods could be converted into hexagonal porous nanorods (at 750 °C), and porous nanorods with corrugated surface structures covered by alternant ( 11 2 ¯ 1 ) and ( 11 2 ¯ 1 ¯ ) planes (at 850 °C and 950 °C). Energy Dispersion Spectrum and Raman spectra are used to carefully study the concentration and vibration modes of the doped carbon species. It explicitly shows that there is a carbonation process around 750 °C and some organic aldehyde molecules transform into carbon with flake form. After investigating their photoluminescence spectra and photocatalytic activities, we conclude that an appropriate etching temperature is the key point to obtain high photocatalytic performance. [ABSTRACT FROM AUTHOR]

• A doping-induced structural transformation from trigonal to monoclinic symmetry is evidenced in the spin-1/2 triangular-lattice antiferromagnet Na 2 Ba 1−x Sr x Co(PO 4) 2 by complementary x-ray diffraction, neutron diffraction and first-principles calculations. • Na 2 SrCo(PO 4) 2 , a compound with imperfect triangular-lattice network of Co2+ ions and a monoclinic symmetry, is synthesized and characterized for the first time, providing a new playground to tune the intriguing quantum magnetism in this family. • Na 2 SrCo(PO 4) 2 exhibits no long-range magnetic order down to 2 K and a similar negative Curie-Weiss temperature as Na 2 BaCo(PO 4) 2 with a perfect triangular lattice, suggesting the robustness of magnetic exchange interaction against the Ba/Sr substitutions. The effects of Sr doping on the structural properties of Na 2 BaCo(PO 4) 2 , a spin-1/2 triangular-lattice antiferromagnet as a quantum spin liquid candidate, are investigated by complementary x-ray and neutron powder diffraction measurements. It is found that in Na 2 Ba 1−x Sr x Co(PO 4) 2 (NBSCPO), the trigonal phase (space group P 3 ̅ m 1) with a perfect triangular lattice of Co2+ ions is structurally stable when the doping level of Sr is below 30% (x ≤ 0.3), while a pure monoclinic phase (space group P 2 1 / a) with slight rotations of CoO 6 octahedra and displacements of Ba2+/Sr2+ ions will be established when the Sr doping level is above 60% (x ≥ 0.6). Such a doping-induced structural transformation in NBSCPO is supported by first-principles calculations and Raman spectroscopy. Na 2 SrCo(PO 4) 2 , a novel spin-1/2 antiferromagnet with glaserite-type structure, although monoclinically distorted, exhibits no long-range magnetic order down to 2 K and a similar negative Curie-Weiss temperature as Na 2 BaCo(PO 4) 2 with a perfect triangular lattice, suggesting the robustness of magnetic exchange interaction against the Ba/Sr substitutions. [ABSTRACT FROM AUTHOR]

Purpose: Pigmented villonodular synovitis (PVNS) is a relatively rare, benign proliferation lesion of the synovium of large joints, but there is not much information available about the disease's aetiology, clinical history, differential diagnosis, treatment, and long-term effects. We conducted a study to analyse these aspects of PVNS. Methods: We reviewed all clinical data for 75 patients with PVNS (81 joints) who were treated either by synovectomy alone or synovectomy plus arthroplasty. Results: In all cases, the diagnosis of PVNS was confirmed by pathological examination. The ratio of males to females was 27:48, and the average age of patients was 46 years (range, 15-80 years). Lesions were located in the knee, hip, or ankle, and pain and swelling were the main symptoms. Of 75 patients, 42 had a history of trauma to the involved joint. Forty-one patients (43 joints) underwent synovectomy alone, and 34 patients (38 joints) underwent synovectomy and arthroplasty together. Of the 75 patients, 61 had full follow-up data. Twelve patients had recurrent legions detected by pathological examinations; four patients had more than two recurrences. Moreover, five patients developed PVNS after arthroplasty. Conclusions: PVNS occurs most often in middle-aged women and most frequently involves the knee, followed by the hip and ankle. The disease's etiology is varied and unclear. Surgical excision alone or with arthroplasty is an effective treatment, but there is a high rate of recurrence. [ABSTRACT FROM AUTHOR]

Abstract: It is found that the Co3O4 nanowires, prepared by directly oxygenating cobalt foil, can keep an antiferromagnetic order until room temperature, quite different from other Co3O4 materials. The opposite behaviors of the curves under 100 and 6500 Oe, and the irreversible magnetic contributions at room temperature are observed. Detailed structural analysis and the splitting of energy levels in different crystalline fields show that the distortions of the crystal lattice make some nonmagnetic Co3+ ions have magnetic moment, which may possibly be the source for these novel behaviors. [Copyright &y& Elsevier]