Preparation of Y^(3+)-doped Bi-_(2)MoO_(6) nanosheets for improved visible-light photocatalytic activity: Increased specific surface area, oxygen vacancy formation and efficient carrier separation

Although Bi_(2)Mo O_(6)(BMO) has recently received extensive attention, its visible-light photocatalytic activity remains poor due to its limited photoresponse range and low charge separation efficiency. In this work, a series of visible-light-driven Y^(3+)-doped BMO(Y-BMO) photocatalysts were synthesized via a hydrothermal method. Degradation experiments on Rhodamine B and Congo red organic pollutants revealed that the optimal degradation rates of Y-BMO were 4.3 and 5.3 times those of pure BMO, respectively. The degradation efficiency of Y-BMO did not significantly decrease after four cycle experiments. As a result of Y^(3+)doping, the crystal structure of BMO changed from a thick layer structure to a thin flower-like structure with an increased specific surface area. X-ray photoelectron spectroscopy showed the presence of highintensity peaks for the O 1s orbital at 531.01 and 530.06 eV, confirming the formation of oxygen vacancies in Y-BMO. Photoluminescence(PL) and electrochemical impedance spectroscopy measurements revealed that the PL intensity and interface resistances of composites decreased significantly, indicating reduced electron–hole pair recombination. This work provides an effective way to prepare high-efficiency Bibased photocatalysts by doping rare earth metal ions for improved photocatalytic performance.

Application of Tropical Flower Species in Leisure Agriculture on Hainan Island

Current development of leisure agriculture on Hainan Island was introduced, and resource advantages of the island in characteristic tropical flower species were further explored. Considering features of leisure agriculture on Hainan Island, development advantages of tropical flower species in the local leisure agriculture was analyzed, and present application of tropical flower species introduced. Such specialized leisure farms as "flower food farm", "flower health-care farm", "flower scientific popularization farm", "flower museum" and "flower theme farm" can be developed, and development orientation of characteristic leisure agriculture on Hainan Island was explored to promote the further development of local flower industry and leisure agriculture.

Graphene-Based Active Tunable Metasurfaces for Dynamic Terahertz Absorption and Polarization Conversion

Simultaneous broadband absorption and polarization conversion are crucial in many practical applications,especially in terahertz communications.Thus,actively tunable metamaterial systems can exploit the graphene-based nanomaterials derived from renewable resources because of the flexible surface conductivity and selective permeability of the nanomaterials at terahertz frequencies.In this paper,we propose a graphene-based active tunable bifunctional metasurface for dynamic terahertz absorption and polarization conversion.The graphene ring presents a certain opening angle(A)along the diagonal of the xoy plane.When A=0°,the proposed metasurface behaves as a broadband absorber.Numerical results show the feasibility of achieving this polarization-insensitive absorber with nearly 100%absorptance,and the bandwidth of its 90%absorptance is 1.22 THz under normal incidence.Alternatively,when A=40°after optimization,the proposed metasurface serves as a broadband polarization convertor,resulting in robust broadband polarization conversion ratio(PCR)curves with a bandwidth surpassing 0.5 THz in the reflection spectrum.To tune the PCR response or the broad absorption spectrum of graphene,we change the Fermi energy of graphene dynamically from 0 to 0.9 eV.Furthermore,both the broadband absorption and the linear polarization conversion spectra of the proposed metasurface exhibit insensitivity to the incident angle,allowing large incident angles within 40°under high-performance operating conditions.To demonstrate the physical process,we present the impedance matching theory and measure electric field distributions.This architecture in the THz frequency range has several applications,such as in modulators,sensors,stealth,and optoelectronic switches.THz wave polarization and beam steering also have broad application prospects in the field of intelligent systems.

Soil Acidification in Response to Acid Deposition in Three Subtropical Forests of Subtropical China

Long-term changes in soil pH, the current status of soil acidification, and the response of bulk soil and soil water pH to experimental nitrogen addition under three subtropical forests were investigated in Dinghushan Biosphere Reserve of subtropical China. The results showed that the mineral soil pH at 0-20 cm depth declined significantly from 4.60-4.75 in 1980s to 3.84-4.02 in 2005. Nitrogen addition resulted in the decrease of pH in both bulk soil and soil water collected at 20-cm depth. The rapid decline of soil pH was attributed to long-term high atmospheric acid deposition (nitrogen and sulphur) therein. The forest at earlier succession stage with originally higher soil pH appeared to be more vulnerable to acid deposition than that at later succession stage with originally low soil pH.

Identification of a stable major QTL for fresh-seed germination on chromosome Arahy.04 in cultivated peanut(Arachis hypogaea L.)

Fresh-seed germination(FSG)impairs peanut production,especially in areas where the peanut harvest season coincides with rainy weather.Developing FSG-resistant cultivars by molecular breeding is expected to mitigate yield loss and quality impairment caused by FSG.However,the genetic control of FSG awaits elucidation.In this study,FSG at 1,3,5,7,and 9 days post-imbibition in three environments were tested,and quantitative-trait loci(QTL)associated with FSG were mapped in a peanut recombinant inbred line population by leveraging existing high-density peanut genetic maps.Of 24 QTL identified in 13 linkage groups,qFSGA04 was a stable major QTL on linkage group 04(LG04).It was consistently detected in five germination stages and three environments.By designing and validating DNA markers in the confidence interval of qFSGA04,we identified one single-nucleotide polymorphism and one In Del closely associated with FSG that could be used as linked markers for FSG resistance in peanut breeding.

New Configuration of Ring Resonator in Photonic Crystal Based on Self-Collimation

We propose a novel ring resonator configuration in a channelless photonic crystal. The proposed ring resonator utilizes the self-collimation effect and the bending and splitting mechanisms of line defects to route the propagation of light, instead of conventional indexed-guided waveguides or photonie crystal band gap waveguides. The finite- difference time-domain method （FDTD） is used to investigate the characteristics of the ring resonator. The new design exhibits an ON-OFF contrast with an extinction ratio of more than 12dB, and has an ultra-compact footprint of 3.3 × 3.3 μm^2 when it operates at the optical communication wavelength λ = 1.55 μm. The design presented may find applications in the areas including ultra-compact optical switch and wavelength filer in integrated optical circuits.

External grind-hardening experiments and its grinding force

The grind-hardening method suitable for external grinding is proposed in this paper and the experiments are carried out on M1432B grinding machine. The hardened layer of the workpiece with cut depth 0.3 mm and speed 0.2 m/min is analyzed. The result indicates the metallurgical structure of the hardened layer is martensite and the top hardness value is 754 HV （about 62.3 HRC）. At the same time, the grinding force, one of the most important factors of external grind-hardening process is modeled, and the measurement method is provided with elastic core clampers. The measurement result shows that the values of both the tangential force and the normal force increase when the cut depth increases, and the top value is 146 N and 656 N with the cut depth value of 0.4 mm. The increment speed and the value of the normal force are larger than the tangential force.

On Identity,Motivation,and Multilingual Education in Asian Contexts

To succeed in today’s competitive job market and globalized world, multilingual education has become a popular trend in developed and developing countries. Asia is a multilingual place with more than 2, 200 languages spoken. As such, in recent years multilingual education in Asia has received an increasing attention from researchers, scholars and language instructors.

基于TAM和感知风险的城市居民再生水回用行为影响因素研究

快速的城市化进程和社会经济发展造成了水资源紧缺和水环境污染,再生水作为一种重要的替代水资源无疑是解决该问题的有效途径。文章将技术接受模型(TAM)和感知风险理论引入再生水回用行为研究领域,建立城市居民再生水回用行为影响因素的理论模型,并提出相应的研究假设。利用问卷收集数据,并对523份有效样本数据的信度与效度进行了验证,在此基础上,采用结构方程对理论模型进行了实证检验。结果表明:(1)感知易用性和感知有用性会影响公众的再生水回用行为态度;(2)公众对再生水的潜在风险意识会显著负向影响其再生水回用行为态度;(3)公众的再生水回用行为态度能显著影响其行为意愿,且还是感知易用性、感知有用性、感知风险作用于行为意愿的中介变量。

Motivation in English for Specific Purpose

Since 1990s,second language learning motivation research presented diversified development tendency in China,particularly an empirical study is on the rise,which verified the validation of foreign language learning motivation theories,and new discoveries are made.In recent years,as the International communication and cooperation increasing,learning English is becoming the basic demand of talents in 21stcentury.While,to a great extent,learning English is closely related to the learning motivation,when learners positively want to learn and make best use of reasonable methods,they can get approving results.Therefore,this essay will discuss motivation in English for specific learning.

Cure for HIV/AIDS with Medicinal Synthetic Aluminum-Magnesium Silicate {Al₄(SiO₄)₃+ 3Mg₂SiO₄→ 2Al₂Mg₃(SiO₄)₃}—A Case Report

HIV/AIDS is an immune deficiency disease, caused by an RNA virus (positively charged pathogen). It is still being regarded as mysteriously incurable but in Nigeria many patients have been cured (they became HIV-antibody and antigen negative) by exploiting electrostatic attraction between pathogens and opposite electrical charges that are on Nanoparticles of Medicinal synthetic Aluminum-magnesium silicate (MSAMS) and by using antioxidants to relieve oxidative stress. To confirm the cure, as permanent, a patient (adult male) whose CD4 count increased (P < 0.05) from 685 to 820 while his viral load became undetectable (<20) and he became HIV-negative (antibody and antigen) following the treatment, was tested, every month, post treatment, for HIV-antibody. He has remained HIV-negative for 10 months without being on any antiretroviral medicine (ARV). Longest window period (period HIV-infected person may test antibody-negative) is only 6 months. These results confirm that treatment with the MSAMS and antioxidants normalizes immunity and terminates HIV-infections.

Challenges and strategies for ultrafast aqueous zinc-ion batteries

With the rising demand for fast-charging technology in electric vehicles and portable devices,significant efforts have been devoted to the development of the highrate batteries.Among numerous candidates,rechargeable aqueous zinc-ion batteries(ZlBs)are a promising option due to its high theoretical capacity,low redox potential of zinc metal anode and inherent high ionic conductivity of aqueous electrolyte.As the strong electrostatic interaction between Zn^(2+)and host generally leads to sluggish electrode kinetics,many strategies have been proposed to enhance fast(dis)charging performance.Herein,we review the state-of-the-art ultrafast aqueous ZIBs and focus on the rational electrode-designing strategies,such as crystal structure engineering,nanostructuring and morphology controlling,conductive materials introducing and organic molecule designing.Recent research directions and future perspectives are also proposed in this review.

Advances of drag-reducing surface technologies in turbulence based on boundary layer control

Our living environment is surrounded by turbulence, which is also a concern of the global energy consumption and the greenhouse gas emission, and the viscous force on the solid-liquid/solid-gas interface is an important part of the turbulence. Reducing friction force in turbulence to the greatest extent is becoming an urgent issue to be resolved at present. In this paper, the various state-of-the-art approaches of drag-reducing and energy-saving technologies based on the boundary layer control are reviewed, focusing on the polymer drag reduction additives, the micro-morphology, the super-hydrophobic surface, the micro air bubbles, the heating wall, the vibrant flexible wall and the composite drag reduction methods. In addition, the mechanisms of different drag reductions based on the boundary layer control and the potential applications in fluid engineering are discussed. This paper aims not only to contribute to a better understanding of drag reduction mechanisms, but also to offer new perspectives to improve the current drag-reducing and energy saving technologies.

Monte Carlo simulations for two-dimensional Ising system far from equilibrium

With a dynamic Monte Carlo simulation, which is free of critical slowing down, the critical behavior of two-dimensional Ising model at non-equilibrium states is investigated. We focus on the two-time autocorrelation function A(t, t' ) to identify the dynamic exponent z in two different evolution stages, quenched from a high temperature state and a completely ordered state to the critical state at TC, re-spectively. By using the heat-bath algorithm, the dynamic critical exponent is estimated as z ≈ 2.16. As a result, the universality of the scaling behavior is verified numerically, and the exponent λC is deter-mined complete by λC = β /ν for the evolutions from an initial completely ordered state.