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In this paper, following the Occam’s razor principle, we have put forward a very simple form of the Dirac neutrino mass matrix M D in the minimal seesaw model with the right-handed neutrino mass matrix being diagonal M R = diag ( M 1 , M 2 ) ; it has one texture zero and only contains three real parameters, whose values can be determined from the neutrino oscillation experimental results. Such a model leads to a neutrino mass matrix M ν ≃ − M D M R − 1 M D T that obeys the TM1 and μ-τ reflection symmetries simultaneously. In this way all the lepton flavor mixing parameters except for θ 13 are predicted; the value of θ 12 is predicted by the TM1 symmetry, while those of θ 23 , δ, ρ and σ by the μ-τ reflection symmetry. And the neutrino masses are predicted to be of the NO case with m 1 = 0 , for which all three light neutrino masses will be pinned down with the help of the experimental results for the neutrino mass squared differences. For these results, the effective Majorana neutrino mass ∣ M ν ee ∣ that controls the rate of the neutrinoless double beta decay is predicted to be 1.6 or 3.8 meV in the case of σ = 0 or π/2. We have also studied the implications of the model for leptogenesis. It turns out that only in the two-flavor leptogenesis regime (which holds in the temperature range 109–1012 GeV) can leptogenesis have a chance to be successful. And a successful leptogenesis can be achieved at M 1 ≃ 1.2 × 10 11 GeV in the case of σ = π/2, but not in the case of σ = 0.

When designing the horn of the ultrasonic transducer for rotary machining, the traditional analytical method cannot consider the complex assembly cross-section of the horn, resulting in a large final simulation error and design error. At the same time, when the design diameter of the transducer is too large, the size of the back mass obtained by the traditional analytical method is too thin. This paper combines the four terminal network method and the finite element method, selects the sandwich piezoelectric transducer, takes the ER spring chuck commonly used in rotary machining as an example, derives the transmission matrix corresponding to the geometric cross-section shape, and then uses the four-terminal network method and the traditional analytical method to design two sets of stepped ultrasonic transducers with the design frequency of 22 kHz for analysis and comparison. Finally, through the analysis, it is verified that the ultrasonic transducer designed by the four-terminal network method has a performance closer to the theoretical design.

In Asakaet al(2021Phys. Rev. D103, 015014), Asaka, Ishida and Tanaka put forward an interesting possibility that the neutrinoless double beta decay can be hidden in the minimal seesaw model with the two right-handed neutrinos having a hierarchical mass structure: the lighter one is lighter enough than the typical Fermi-momentum scale of nuclei while the heavier one is sufficiently heavy to decouple from the neutrinoless double beta decay. Then, in the basis where the mass matrices of the charged leptons and right-handed neutrinos are diagonal, for some particular texture of the Dirac neutrino mass matrixMD, the neutrinoless double beta decay can be hidden. In this paper, on top of this specified model, we study the interesting scenario thatMDfurther obeys the TM1 symmetry orμ–τreflection symmetry which are well motivated by the experimental results for the neutrino mixing parameters.

The plastic deformation properties of cylindrical pre-void aluminum–magnesium (Al–Mg) alloy under uniaxial tension are explored using molecular dynamics simulations with embedded atom method (EAM) potential. The factors of Mg content, void size, and temperature are considered. The results show that the void fraction decreases with increasing Mg in the plastic deformation, and it is almost independent of Mg content when Mg is beyond 5%. Both Mg contents and stacking faults around the void affect the void growth. These phenomena are explained by the dislocation density of the sample and stacking faults distribution around the void. The variation trends of yield stress caused by void size are in good agreement with the Lubarda model. Moreover, temperature effects are explored, the yield stress and Young’s modulus obviously decrease with temperature. Our results may enrich and facilitate the understanding of the plastic mechanism of Al–Mg with defects or other alloys.

In this letter, we make an attempt to embed the μ–τ reflection symmetry (which predicts maximal atmospherical mixing angle and Dirac CP phase) in the Friedberg-Lee neutrino model (which employs a translational flavor symmetry and keeps one neutrino mass vanishing) and study the consequences of such a combination.

Architecture has its own language, which records stories and retains emotions in a special way. Only time will inevitably make buildings old and inconvenient, but now our choice is no longer to abandon or destroy them. We can add functions and extend connotations through transformation, and the existing buildings can be revitalized again and move us. On the other hand, the construction industry already accounts for 40 percent of the world’s energy use, and in the developed world, around 65 percent of the total projected building stock by 2060 has already been built, a reminder that perhaps we really need to look to the existing buildings around us in the future.

Given its briefness and predictability, the minimal seesaw -- a simplified version of the canonical seesaw mechanism with only two right-handed neutrino fields -- has been studied in depth and from many perspectives, and now it is being pushed close to a position of directly facing experimental tests. This article is intended to provide an up-to-date review of various phenomenological aspects of the minimal seesaw and its associated leptogenesis mechanism in neutrino physics and cosmology. Our focus is on possible flavor structures of such benchmark seesaw and leptogenesis scenarios and confronting their predictions with current neutrino oscillation data and cosmological observations. In this connection particular attention will be paid to the topics of lepton number violation, lepton flavor violation, discrete flavor symmetries, CP violation and antimatter of the Universe., Comment: 111 pages, 23 figures, 9 tables, final version published in Reports on Progress in Physics as a Review Article

Red-fleshed apple (Malus niedzwetzkyana dieck) was used as the fermentation material, and the fermentation mode of red-fleshed apple cider was studied by using alcohol fermentation as control (CK), simultaneous malolactic fermentation (SIM) and sequential MLF (SEQ). The main chemical parameters, antioxidant activities and sensory quality were analyzed to evaluate the quality of red-fleshed apple cider. Compared with the cider without lactic acid bacteria, the total phenolics contents (TPC) and total anthocyanins contents (TAC) in MLF apple cider were significantly decreased, while the total flavonoids content (TFC) were significantly increased. Among them, the TPC and TAC in apple cider obtained by SIM were the highest, while the TFC in apple cider obtained by SEQ. In addition, compared with the control group, the pH of cider obtained by SEQ and SIM was significantly increased by about 0.25 units, while the total acidity was significantly decreased. Therefore the taste of cider obtained from SIM and SEQ were significantly improved, and the cider obtained by SIM got the highest score by sensory analysis, which scored the highest for floral and fruitiness notes. These results indicated that SIM was an effective way to produce red-fleshed apple cider.

In this letter, we experimentally demonstrated a simplified rotating structured light consisting of two overlapping perfect vortices that are generated by focusing two coaxial Bessel beams with different longitudinal wavenumbers. Named perfect rotating wave (PRW), this beam inherits the characteristic of perfect vortex whose radius is controllable and frozen wave whose transverse intensity profile rotates along transmission direction. The no-sidelobes intensity distribution of PRW facilitates the orientation measurement. Because of the linear responds to the Bessel beams’ propagation distance, the orientation of PRW could be applied in remote sensing to measure optical path, temperature, refractive index and so on.

Landslide is one of the most common disasters in nature and is a kind of slope failure. Many countries in the world suffered, because of its wide distribution, frequent occurrence and great harm. In China, the national economy and people’s lives and property suffer heavy losses due to the landslide disaster. In this paper, first of all, we used the Bishop method to theoretically analyze the stability of a landslide in Sichuan Province, and then we established a simulation model in Flac3D, the rock and soil mechanics calculation software developed by ITASCA company in the United States, to analyze the stability of the landslide under complex conditions. Finally, the results of theoretical analysis and simulation are consistent, which can provide ideas and methods for geological disaster prevention in the future.

Plasmonic metallic nanostructure with unique hot carrier-driven photocatalysis has recently emerged as a promising photocatalyst. Herein, we show that the plasmonic photocatalysis can be significantly promoted by supporting bimetallic Au@Ag nanoalloys (NAs) on graphene oxide (GO). The obtained Au3@Ag1/GO (molar ratio of Au to Ag∼3:1) with improved synergistic effects provides a remarkable higher visible-light (>400 nm) photocatalytic activity for a complete degradation (99.36%) of tetracycline hydrochloride (TCH) molecules within 70 min, while about 61.74% or 62.38% via monometallic Au/GO or Ag/GO. The optimum photocatalytic performance is attributed to the production of high yield hot carriers on NAs with enhanced localized surface plasmon resonance property and the pronounced photoinduced electron-transfer ability of modified GO support by overgrowth of NAs. These findings enable the optimal Au3@Ag1/GO to become an appealing high-performance photocatalyst for promoting diverse photochemical reactions.

Aiming at the problem of insufficient bearing capacity of collapsible loess in highway subgrade engineering, taking the second phase of KKH project in Pakistan as an example, Based on the analysis of the physical and mechanical properties of collapsible loess in this area and the actual situation of the project, the most effective construction technology is explored. The construction technology of replacing natural gravel is analyzed, and summarizes the actual operation of the construction methods, to provide some theoretical basis and construction reference for related projects. The results show that the design and construction requirements can only be met under the condition of strict implementation of the norms and standards, combined with the actual situation of the project, and the most effective construction technology explored can be applied to the construction of highway subgrade.

The degree of regional economic integration is one of the main factors affecting the efficiency of regional agricultural product circulation, and the two are generally positively correlated. My country’s agricultural product logistics have been developed for a long time, but it is still low in level, high in cost and large in the loss. We analyzed the current situation and existing problems of agricultural product logistics, combined with the background of big data, summarize the role of big data in agricultural product logistics, and the measures for agricultural product logistics construction in the era of big data. To effectively promote the improvement of regional agricultural product circulation efficiency, after analyzing the influencing factors, this paper proposes that the government should build a full marketing system to improve circulation efficiency. It builds a multi-channel platform to improve circulation efficiency and create an era of big data. Data integration and smooth information have further improved the circulation efficiency of China’s agricultural products.

Chemically synthetic nanomotors can consume fuel in the environment and utilize the self-generated concentration gradient to self-propel themselves in the system. We study the collective dynamics of an ensemble of sphere dimers built from linked catalytic and noncatalytic monomers. Because of the confinement from the fuel field and the interactions among motors, the ensemble of dimer motors can self-organize into various nanostructures, such as a radial pattern in the spherical fuel field and a staggered radial pattern in a cylindrical fuel field. The influence of the dimer volume fraction on the self-assembly is also investigated and the formed nanostructures are analyzed in detail. The results presented here may give insight into the application of the self-assembly of active materials.

Organic–inorganic hybrid new crystals, [(parachloroanilinum+)(18-crown-6)][ClO4−](CH3COCH3) and [(parachloroanilinum+)(18-crown-6)][BF4−](CH3COCH3), with high phase transition temperatures and noncentrosymmetric structures were grown. Their physical properties, including their structures, phase transitions, and dielectric, piezoelectric and photoluminescent properties, were systematically investigated. A phase transition at 71 °C was successively detected and confirmed by DSC and dielectric measurements. Piezoelectric features were clearly verified by piezoresponse force microscopy. Both compounds show strong and wide photoluminescent properties. All the results make the two compounds promising candidates for potential applications in the piezoelectric and optical fields.

Named entity linking(NEL) for Chinese short text is regard as a ranking task. Current research on NEL is mostly about long text and rich language, which may unfit Chinese short text situation. We propose a multi-cross matching network(CMN) to solve these problems. CMN first matches a candidate and the mention with the text in three different degree, and extracts important matching information through a couple of convolution and pooling layers. Then sequence vectors are accumulated through a Gated Recurrent Unit(GRU) which distill relationships among words in texts. Finally we use dynamic average algorithm to calculate the mention-entity similarity. Experimental results demonstrate that CMN exhibits the outstanding performance on several Chinese datasets for the Chinese short text entity linking problem.

Semiconductor-metal nanocomposites were demonstrated to be great potential applications for their unique structures. In this work, Cu2O-Ag nanocomposites with tunable optical property were prepared by laser molecular beam epitaxy with an alternative deposition way. The growth process was characterized by in situ reflection high-energy electron diffraction and in situ X-ray photoelectron spectroscopy. Due to the surface plasmon resonance, the absorption peaks of Cu2O-Ag can be easily modulated from 618 nm to 650 nm by increasing Ag laser pulses. The corresponding band gap changed from 2.01 eV to 2.74 eV. The growth mechanism was also discussed in detail. The results provide a new route to control the optical absorption of semiconductor-metal oxide nanocomposites by an easy way.

It is difficult to detect single-phase grounding fault in non-effective neutral point to ground system because of its weak current and unstable arc. In this paper, a kind of self-adaptive notch filter is used to extract the fundamental wave of current signals. This method is verified by Matlab/Simulink simulation. The result confirms that the method can realize fault line detection timely and accurately.

Nonreciprocal devices are indispensable for building quantum networks and ubiquitous in modern communication technology. Here, we study perfect optical nonreciprocity in a three-mode optomechanical system with mechanical driving. The scheme relies on the interference between optomechanical interaction and mechanical driving. We find perfect optical nonreciprocity can be achieved even though nonreciprocal phase difference is zero if we drive the system by a mechanical driving with a nonzero phase. We obtain the essential conditions for perfect optical nonreciprocity and analyze properties of the optical nonreciprocal transmission. These results can be used to control optical transmission in quantum information processing.

We propose a metal-photonic crystal (PC) cavity structure, which had a narrow band absorption in the band-gap of PC. The electric field was strongly enhanced near the cavity when the wavelength of incident light corresponded to the absorption peak, which meant the proposed structure could generate Tamm plasmon polaritons. Through adjusting the thickness of the cavity, the wavelength of absorption peak could be tuned from ~1510 nm to ~1690 nm in this work. Meanwhile, the refractive index of the cavity also affected the absorption spectrum. Importantly, the proposed structure could realize perfect absorption at suitable conditions, and the maximum absorptance reached 0.999 95. The period number of PC and the thickness of silver film also had great influence on the absorption spectrum, which has also been investigated in this paper.

A new mononuclear gadolinium complex: [Gd(tfac)3(NIT-2thz)] (tfac = trifluoroacetylacetonate; NIT-2thz = 2-(2'-thiazolyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) was synthesized, structurally and magnetically characterized. Single-crystal X-ray structural analysis reveals that this complex crystallized in the C2/c space groups. Each central Gd ion is eight-coordinated by three bischelate tfac ligands and one radical ligand. Through magnetic study, ferromagnetic Gd (III)–radical coupling of this complex were observed.

In the framework in which supersymmetry is used for understanding fermion masses rather than stabilizing the electroweak scale, we elaborate the phenomenological analysis for the neutrino physics. A relatively large $\sin{\theta_{13}}$ is the natural result. The model further predicts vanishingly small CP violation in neutrino oscillations. And $\theta_{23}$ is not necessarily maximal. While the high scale supersymmetry generically results in a Higgs mass of about 141 GeV, our model reduces this mass via introducing SU(2)$_L$ triplet fields which also contribute to neutrino masses., Comment: 13 pages, no figure, revtex4, revised version

This paper reports the plasmonic lasing of a split ring filled with gain material in water. The lasing mode (1500 nm) is far from the pump mode (980 nm), which can depress the detection noise from the pump light. The laser intensities of the two modes simultaneously increase by more than 103 in amplitude, which can intensify the absorption efficiency of the pumping light and enhance the plasmonic lasing. The plasmonic lasing is a sensitive sensor. When a single protein nanoparticle (n = 1.5, r = 1.25 nm) is trapped in the gap of the split ring, the lasing spectrum moves by 0.031 nm, which is much larger than the detection limit of 10−5 nm. Moreover, the lasing intensity is also very sensitive to the trapped nanoparticle. It reduces to less than 1/600 when a protein nanoparticle (n = 1.5, r = 1.25 nm) is trapped in the gap.

Phase transitions in Bi4-xSmxTi3O12 single crystals in the Sm concentration range of x≤0.61 were studied. The phase transition near 670 °C was found to remain almost unchanged in the concentration range of 0≤x≤0.61. Below the transition temperature of 670 °C, dielectric anomaly showing phase transitions was found in BSmT-x, depending on the concentration x. It was confirmed that the triggered transition from the tetragonal phase to the monoclinic phase, observed in Bi4Ti3O12, splits into two phase transitions by adding Sm cations, i.e., from the tetragonal phase to the orthorhombic phase and further to the monoclinic phase. The temperature-concentration phase diagram of the BSmT-x system was clarified.

Phase transitions in Bi4-xLaxTi3O12 (BLT-x) mixed crystals with a low La concentration (x

We study the dynamics of two electrons confined in double quantum dots driven by a rotating magnetic field. An exact solution of the Schrodinger equation with explicitly time-dependent Hamiltonian is obtained in terms of the time-dependent gauge transformation. The spin separation is investigated for various initial states.

In a cation exchange process developed recently for epitaxy of HgBa2CaCu2O6 (Hg-1212) thin films, TlBa2CaCu2O7 (Tl-1212) or Tl2Ba2CaCu2O9 (Tl-2212) precursor films were employed as the precursor matrices and Hg-1212 was obtained by replacing Tl cations on the precursor lattice with Hg cations. The reversibility of the cation exchange dictates directly the underlying mechanism. Following our recent success in demonstrating a complete reversibility within '1212' structure, we show the conversion from Hg-1212 to Tl-2212 can be achieved via two steps: conversion from Hg-1212 to Tl-1212 followed by Tl intercalation to form double Tl–O plans in each unit cell. The demonstrated reversibility of the cation exchange process has confirmed the process is a thermal perturbation of weakly bonded cations on the lattice and the direction of the process is determined by the population ratio between the replacing cations and that to be replaced.

This paper describes an application of PIV (particle image velocimetry) and two-tracer PLIF (planar laser-induced florescence) techniques to optimize the in-cylinder flow and to visualize two fuels distribution simultaneously for developing a fuel stratification engine. This research was carried out on a twin-spark four-valve SI engine. The PIV measurement results shows that a strong tumbling flow was produced in the cylinder as the intake valves were shrouded. The flow exhibited a symmetrical distribution in the plane perpendicular to the cylinder axis from the early stage of intake until the late stage of compression. This flow pattern helps to stratify the two fuels introduced from separate ports into two regions laterally. The stratification of fuels was observed visually by the two-tracer PLIF technique. During the PLIF measurement, two tracers, 3- pentanone and N, N-dimethylaniline (DMA), were doped into two fuels, hexane and iso-octane, respectively. Their fluorescence emissions were separated by two optical band-pass filters and recorded by a single ICCD camera simultaneously via an image doubling system. The PLIF measurement result shows that two fuels were well stratified.

Absorption of an photonic configuration with 2D accumulation electron gas is theoretically investigated in the first optical window of biological tissue. The configuration consists of a Bragg mirror, an ITO-dielectric heterostructure and a metal film. Our results show that the configuration can realize perfect absorption (reaches 99.98%) of specific wavelength light at matched electron density of the accumulation electron gas. Moreover, the influences of different parameters on the perfect absorption are investigated, which allows us accurately tune the absorption spectrum of the configuration. In addition, manufacture discrepancies of film thicknesses are simulated through introducing random thickness errors in the configuration. It is found that the discrepancies of film thicknesses dramatically affect the absorption spectrum of the configuration. Fortunately, this manufacture impact can be perfectly remedied by changing the electron density of the accumulation electron gas and the incident angle of light.

This letter presents a high speed 2:1 regenerative dynamic frequency divider with an active transformer fabricated in 0.7 μ m InP DHBT technology with f T of 165 GHz and f max of 230 GHz. The circuit includes a two-stage active transformer, input buffer, divider core and output buffer. The core part of the frequency divider is composed of a double-balanced active mixer (widely known as the Gilbert cell) and a regenerative feedback loop. The active transformer with two stages can contribute to positive gain and greatly improve phase difference. Instead of the passive transformer, the active one occupies a much smaller chip area. The area of the chip is only 469×414 μ m 2 and it entirely consumes a total DC power of only 94.6 mW from a single -4.8 V DC supply. The measured results present that the divider achieves an operating frequency bandwidth from 75 to 80 GHz, and performs a -23 dBm maximum output power at 37.5 GHz with a 0 dBm input signal of 75 GHz.

Aerogel, a highly porous material, is attracting increasing attention owing to low thermal conductivity and high specific surface area. Freeze-drying technology has been employed to produce nano-cellulose aerogels; however, the resultant product has low specific surface areas. Here, a modified approach to prepare nano-cellulose aerogels was reported, which involves tert-butyl alcohol as a solvent. Nano-cellulose aerogels were prepared via a spontaneous gelation fashion using calcium chloride solution, followed by tert-butyl alcohol solvent displacement and freeze drying. Addition of calcium chloride (0.25%) accelerated the physical gelation process. The application of tert-butyl alcohol as a solvent contributed to preservation of gel network. The obtained spherical nano-cellulose aerogels had a shrinkage rate of 5.89%. The specific surface area and average pore size was 164. 9666 m2 g−1 and 10.01 nm, respectively. Additionally, nano-cellulose aerogels had a comparable thermal degradation property when compared to microcrystalline cellulose. These biophysical properties make nano-cellulose aerogels as a promising absorption material.

The modulation of indium tin oxide (ITO) films through surface charge accumulation plays an important role in many different applications. In order to elaborately study the modulation, we measured the dielectric constant of the modulated layer through examining the excitation of surface plasmon polaritons. Charges were pumped on the surfaces of ITO films through applying high voltage in appropriate directions. Experiments unveiled that the dielectric constant of the modulated layer had large variation along with the nanoscale charge accumulation. Corresponding numerical results were worked out through combining Drude model and Mayadas–Shatzkes model. Based on the above results, we deduced the time and voltage dependences of accumulated charge density, which revealed a long-time charge accumulation process.