Photoredox‐based C−H bond functionalization constitutes one of the most powerful and atom‐economical approaches to organic syntheses. During this type of reaction, single electron transfer takes ...place between the photocatalyst (PC) and redox‐ active substrates. Electrosynthesis also involves electron transfer between substrates and electrodes. In this paper, we focus upon electrochemical cross‐coupling of C(sp2)−H with aryldiazonium salts and have developed an efficient electrochemical approach to the Minisci‐type arylation reaction. The constant current paired electrosynthesis proceeds in a simple undivided cell without external supporting electrolyte, features a wide range of substrates and is easy to scale‐up. These results demonstrate that photoredox‐based cross‐coupling of C(sp2)−H with aryldiazonium salts can also proceed successfully under paired electrolysis conditions, thereby contributing to understanding of the parallels between photosynthesis and electrosynthesis.
Efficient intermolecular dehydrogenative cross‐coupling of N‐alkyloxyamides with xanthenes is reported. The protocol is carried out in an undivided cell under constant current conditions employing ...simple, cheap and readily available ferrocene (Fc) as a redox catalyst. Cyclic voltammetry and control experiments disclosed that the dehydrogenative cross‐coupling reaction may proceed via an amidyl radical.
Summary of main observation and conclusion
An efficient electrochemical access to the non‐symmetric biphenols using tri(p‐bromophenyl)amine (TBPA) as a redox mediator has been developed. The ...electrochemical protocol features highly selective cross‐coupling products in up to 83% yield, instead of forming homo‐coupling ones.
Electrochemical cross‐coupling of unprotected phenol with naphthols and phenols using tri(p‐bromophenyl)amine as mediator has been reported.
In this paper, we establish several theorems about the existence and the forms of entire solutions with finite order for some systems of quadratic trinomial functional equations with two complex ...variables, which are some improvements and generalizations of the previous theorems given by Xu and Cao, Xu, Liu and Li. Moreover, some examples are given show that there are significant differences in the forms of transcendental entire solutions with finite order of some systems of functional equations with complex between two variables and a single variable.
In this paper, we investigate fixed points of meromorphic functionsf(z) for difference Riccati equations, and obtain some estimates of exponents of convergence of fixed points off(z) and ...shiftsf(z+n), differences Δf(z) =f(z+ 1) −f(z) and divided differences
Δ
f
(
z
)
f
(
z
)
.
2010Mathematics Subject Classification: 30D35, 39B12.
Key words and phrases: Riccati equation, Meromorphic function, Difference, Fixed points.
The most effective carbide-forming elements titanium and niobium were added into hardfacing alloy.Formation and composition of carbides in the hardfacing alloy were investigated by means of optical ...microscope（OM）,scanning electron microscope（SEM）,X-ray diffraction（XRD）and energy-dispersive spectrometer（EDS）.Hardness and impact toughness of the hardfacing alloy were measured.The thermodynamics and formation mechanism of carbides were also discussed.It is found that the carbides consist of TiC and NbC which are able to form directly from welding pool during the welding process.The formation mechanism of carbides involves nucleation of TiC followed by epitaxial precipitation of NbC on the surface of TiC.The formation of titanium and niobium carbides can obviously refine the microstructure and deplete the carbon in the matrix.The micros tructure transforms to well-distributed carbides and a tough martensite matrix,contributing to a good combination of high hardness and high toughness in the hardfacing alloy.
An efficient electrocatalytic functionalization of
-arylglycine esters is reported. The protocol proceeds in an undivided cell under constant current conditions employing the simple, cheap and ...readily available
-Bu
NI as the mediator. In addition, it is demonstrated that the mediated process is superior to the direct electrochemical functionalization.
Antimony selenide (Sb
2
Se
3
) is a promising absorber material for thin film photovoltaics because of its attractive material, optical and electrical properties. In recent years, the power ...conversion efficiency (PCE) of Sb
2
Se
3
thin film solar cells has gradually enhanced to 5.6%. In this article, we systematically studied the basic physical properties of Sb
2
Se
3
such as dielectric constant, anisotropic mobility, carrier lifetime, diffusion length, defect depth, defect density and optical band tail states.We believe such a comprehensive characterization of the basic physical properties of Sb
2
Se
3
lays a solid foundation for further optimization of solar device performance.
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