Recent advances and perspectives in cobalt‐based heterogeneous catalysts for photocatalytic water splitting,CO_(2) reduction,and N_(2) fixation

Solar‐driven conversion of carbon dioxide,water and nitrogen into high value‐added fuels(e.g.H_(2),CO,CH_(4),CH_(3)OH,NH_(3) and so on)is regarded as an environmental‐friendly and ideal route for relieving the greenhouse gas effect and countering energy crisis,which is an attractive and challenging topic.Hence,various types of photocatalysts have been developed successively to meet the requirements of these photocatalysis.Among them,cobalt‐based heterogeneous catalysts emerge as one of the most promising photocatalysts that open up alluring vistas in the field of solar‐to‐fuels conversion,which can effectively enhance photocatalytic efficiency by extending light absorption range,promoting charge separation,providing active sites,and lowering reaction barrier.In this review,we first present the working principles of cobalt‐based heterogeneous catalysts for photocatalytic water splitting,CO_(2) reduction,and N_(2) fixation.Second,five efficient strategies including surface modification,morphology modulation,crystallinity controlling,crystal engineering and doping,are discussed for improving the photocatalytic performance with different types cobalt‐based catalysts(cobalt nanoparticles and single atom,oxides,sulfides,phosphides,MOFs,COFs,LDHs,carbide,and nitrides).Third,we outline the applications for the state‐of‐the‐art photocatalytic CO_(2) reduction and water splitting,and nitrogen fixation over cobalt‐based heterogeneous catalysts.Finally,the central challenges and possible improvements of cobalt‐based photocatalysis in the future are presented.The purpose of this review is to summarize the past experience and lessons,and provide reference for the further development of cobalt‐based photocatalysis technology.

Role of Gate in Triode-Structure for Carbon Nanotube Cold Cathode

Field emission properties of carbon nanotube cold cathode （CNT-CC） of triode- and diode-structure have been investigated by using the finite element method of numerical simulation. Specially, the effects of gate voltage and hole radius R on the emission properties have been analyzed based on the finite element method. Results indicate that the gate can make the excitation electric field E increase, turn-on voltage decrease, and the emission current density J rise. The result shows that the E reaches its maximum value at the top of carbon nanotube （CNT）, and the optimum field emission performance can be obtained when R is equal to 10 times the diameter of the carbon nanotube.

Decaying solitary waves propagating in one-dimensional damped granular chain

We numerically investigate the nonlinear waves propagating in a one-dimensional particle chain when the damping effect is taken into account. It is found that decaying solitary waves exist, in which the amplitude of the wave decreases exponentially as time increases. Meanwhile, the velocity of the solitary wave also slows down as time goes. This result implies that the damping coefficient is an important parameter in such a nonlinear system. Theoretical analysis has also been done by the reductive perturbation method. The result indicates that the nonlinear waves propagating in such a system can be described by the damped KdV equation.

Small amplitude double layers in an electronegative dusty plasma with q-distributed electrons

The small amplitude dust ion-acoustic double layers in a collisionless four-component unmagnetized dusty plasma system containing nonextensive electrons, inertial negative ions, Maxwellian positive ions, and negatively charged static dust grains are investigated theoretically. Using the pseudo-potential approach and reductive perturbation method, an energy integral equation for the system has been derived and its solution in the form of double layers is obtained. The results appear that the existence regime of the double layer is very sensitive to the plasma parameters, e.g., electron nonextensivity,negative-to-positive ion number density ratio etc. It has been observed that for the selected set of parameters, the system supports rarefactive,（compressive） double layers depending upon the degree of nonextensivity of electrons.

Enlightenment of Confucian Thoughts of Music Education on Contemporary General Music Education

In the pre-Qin period,Confucius proposed six subjects namely the etiquette,music,archery,driving,literacy,and calculation.Among the six subjects,music was ranked the second.Among them,traditional education in China can fully reflect the importance of music education,and the essence and core of music education can be reflected from the requirements of aesthetic education.In recent years,with the continuous development and improvement of production and life,the theme of education in today’s society has changed,and quality education is the center and focus of education today.Moreover,people begin to focus on how to inherit and publicize the traditional music culture.As the music culture is of great importance,many people are encouraged to continue to practice and publicize the traditional music.The main point of this article is Confucian theory of music education.

Riser Simulation and Radial Porosity Distribution Characterization for Gas-Fluidized Bed of Cork Particles

Numerical simulations are carried out for gas-solid fluidized bed of cork particles, using discrete element method. Results exhibit the existence of a so-called anti core-annular porosity profile with lower porosity in the core and higher porosity near the wall for non-slugging fluidization. The tendency to form this unfamiliar anti core-annular porosity profile is stronger when the solid flux is higher. There exist multiple inflection points in the simulated axial solid volume fraction profile for non-slugging fluidization. Results also show that the familiar core-annular porosity profile still appears for slugging fluidization. In addition, the classical choking phenomenon can be captured at the superficial gas velocity slightly lower than the correlated transport velocity.

Investigation of the Rayleigh–Taylor instability in charged fluids

The present study shows that the Rayleigh–Taylor(RT)instability and its growth rate are strongly dependent on the charge-mass ratio of charged particles in a charged fluid.A higher charge-mass ratio of the charged fluid appears to result in a stronger effect of the magnetic field to suppress the RT instability.We study the RT instabilities for both dusty plasma(small chargemass ratio of charged particles)and ion-electron plasma(large charge-mass ratio of charged particles).It is found that the impact of the external magnetic field to suppress the RT instability for ion-electron plasma is much greater than that for dusty plasma.It is also shown that,for a dusty plasma,in addition to region parameters such as the external magnetic field,region length,its gradient,as well as dust particle parameters such as number density,mass,and charge of dust particles,the growth rate of the RT instability in a dusty plasma also depends on parameters of both electrons and ions such as the number densities and temperatures of both electrons and ions.

Luminescent Properties of Terbium（Ⅲ） and Europium（Ⅲ）Complexes with Six 4-Acetyl-bispyrazolones

The lowest triplet energy levels of the six ligands（T） were determined to be 22989 cm-1[1,3-bis-（1＇-phenyl-3＇-methyl-5＇-pyrazolon-4＇）-1,3-propanedione,BPMPTD],23148 cm-1[1,4-bis-（1＇-phenyl-3＇-methyl-5＇-pyrazolon-4＇）-1,4-butanedione,BPMPBD],23419 cm-1[1,5-bis-（1＇-phenyl-3＇-methyl-5＇-pyrazolon-4＇）-1,5-pentane-dione,BPMPPD],23310 cm-1[1,6-bis-（1＇-phenyl-3＇-methyl-5＇-pyrazolon-4＇）-1,6-hexanedione,BPMPHD],21978 cm-1[1,9-bis-（1＇-phenyl-3＇-methyl-5＇-pyrazolon-4＇）-l,9-nonanedione,BPMPND] and 21930 cm-1[1,10-bis-（1＇-phenyl-3＇-methyl-5＇-pyrazoion-4＇）-1,10-decanedione,BPMPDD],respectively.It was explained satisfactorily that the six ligands are more efficient for sensitizing the luminescence of Tb3＋ than that of Eu3＋ at room temperature,and the order of the luminescent intensities for the Tb3＋ complexes is explained by the relative energy gap between T and 5DJ of Tb3＋ or Eu3＋.As a conclusion,when 2700 cm-1＜△E（T-5D4）＜3000 cm-1,the luminescent intensity of the Tb3＋ complex is the strongest.This means that the lowest triplet energy level of the ligand is a chief factor to dominate RE3＋luminescence.