The determination of copper by MIP-AES was investigated in detail. Aqueous samples were introduced from an ultrasonic nebulizer and the solvent was removed by a desolvation device before introduction of the aerosol in...The determination of copper by MIP-AES was investigated in detail. Aqueous samples were introduced from an ultrasonic nebulizer and the solvent was removed by a desolvation device before introduction of the aerosol into the MIP. The desolvation system consisted of a condenser associated with a concentrated H2SO4 absorption cell. Various experimental conditions and interferences from easily ionised elements (EIEs) were also studied and some practical samples were analyzed.展开更多
The velocity of critical surface at microwave band in laser-induced plasma was measured and the results are presented. The results indicate that the velocity of critical surface with low electron density is larger tha...The velocity of critical surface at microwave band in laser-induced plasma was measured and the results are presented. The results indicate that the velocity of critical surface with low electron density is larger than that with the high one; and the velocity of critical surface increases with the laser power density.展开更多
In general, atomic emission spectrometry (AES) is an excellent technique for determination of metal elements. However, its capability of determining nonmetals has not been developed well. The major reasons are the res...In general, atomic emission spectrometry (AES) is an excellent technique for determination of metal elements. However, its capability of determining nonmetals has not been developed well. The major reasons are the resonance lines of most nonmetals lie in the vacuum ultraviolet spectral region and the ionic lines of these elements are difficult to be used because the ionization potentials of the elements are very high. And furthermore only He plasma can efficiently excit those ionic resonance lines. The practical application of HeICP-AES to determining the nonmetals is also difficult because its operating and perchace costs are very high. In contrast to HeICPAES, the costs of He microwave induced plasma (MIP)-AES are relatively low, HeMIP has a high excitation capability which can excite ionic lines of various nonmetals and the nonmetals can be determined by HeMIP-AES with a high sensitivity.展开更多
Using a low power microwave generator and a surfatron discharge cavity, Ti3O5 was synthesized via the hydrogenation of TiO2 in surface wave induced microwave plasma. Besides, the chemical behavior of hydrogen in the p...Using a low power microwave generator and a surfatron discharge cavity, Ti3O5 was synthesized via the hydrogenation of TiO2 in surface wave induced microwave plasma. Besides, the chemical behavior of hydrogen in the plasma and its influence on the formation of Ti3O5 were preliminarily studied.展开更多
Atmospheric pressure plasmas are not only powerful sources for excitation but also very good atomizers. In the early developing stage, the inductively coupled plasma (ICP) was investigated as an atomizer for atomic ab...Atmospheric pressure plasmas are not only powerful sources for excitation but also very good atomizers. In the early developing stage, the inductively coupled plasma (ICP) was investigated as an atomizer for atomic absorption spectrometry (AAS). A multiple pass system,a T-shaped plasma cell,and a long-path torch was used to increase the absorption path length. But all these ICP-AAS systems gave low sensitivities for most展开更多
Microwave induced plasma torches find wide applications in material and chemical analysis.Investigation of a coaxial electrode microwave induced plasma(CE–MIP)torch is conducted in this study,making it available for ...Microwave induced plasma torches find wide applications in material and chemical analysis.Investigation of a coaxial electrode microwave induced plasma(CE–MIP)torch is conducted in this study,making it available for glass surface modification and polishing.A dedicated nozzle is designed to inject secondary gases into the main plasma jet.This study details the adaptation of a characterisation process for CE–MIP technology.Microwave spectrum analysis is used to create a polar plot of the microwave energy being emitted from the coaxial electrode,where the microwave energy couples with the gas to generate the plasma jet.Optical emission spectroscopy analysis is also employed to create spatial maps of the photonic intensity distribution within the plasma jet when different additional gases are injected into it.The CE–MIP torch is experimentally tested for surface energy modification on glass where it creates a super-hydrophilic surface.展开更多
We studied experimentally the effect of microwaves （MWs） on the enhancement of plasma emission achieved by laser-induced breakdown spectroscopy （LIBS）. A laser plasma was generated on a calcium oxide pellet by a N...We studied experimentally the effect of microwaves （MWs） on the enhancement of plasma emission achieved by laser-induced breakdown spectroscopy （LIBS）. A laser plasma was generated on a calcium oxide pellet by a Nd：YAG laser （5 m J, 532 nm, 8 ns） in reduced-pressure argon surrounding gas. A MW radiation （400 W） was injected into the laser plasma via a loop antenna placed immediately above the laser plasma to enhance the plasma emission. The results confirmed that when tile electromagnetic field was introduced into the laser plasma region by the MWs, the lifetime of the plasma was extended from 50 to 500 μs, similar to the MW duration. Furthermore, the plasma temperature and electron density increased to approximately 10900 K and 1.5×10^18 cm^-3, respectively and the size of the plasma emission was extended to 15 mm in diameter. As a result, the emission intensity of Ca lines obtained using LIBS with MWs was enhanced by approximately 200 times compared to the case of LIBS without MWs.展开更多
基金Supported by the Natinoal Natural Science Foundation of China.
文摘The determination of copper by MIP-AES was investigated in detail. Aqueous samples were introduced from an ultrasonic nebulizer and the solvent was removed by a desolvation device before introduction of the aerosol into the MIP. The desolvation system consisted of a condenser associated with a concentrated H2SO4 absorption cell. Various experimental conditions and interferences from easily ionised elements (EIEs) were also studied and some practical samples were analyzed.
文摘The velocity of critical surface at microwave band in laser-induced plasma was measured and the results are presented. The results indicate that the velocity of critical surface with low electron density is larger than that with the high one; and the velocity of critical surface increases with the laser power density.
文摘In general, atomic emission spectrometry (AES) is an excellent technique for determination of metal elements. However, its capability of determining nonmetals has not been developed well. The major reasons are the resonance lines of most nonmetals lie in the vacuum ultraviolet spectral region and the ionic lines of these elements are difficult to be used because the ionization potentials of the elements are very high. And furthermore only He plasma can efficiently excit those ionic resonance lines. The practical application of HeICP-AES to determining the nonmetals is also difficult because its operating and perchace costs are very high. In contrast to HeICPAES, the costs of He microwave induced plasma (MIP)-AES are relatively low, HeMIP has a high excitation capability which can excite ionic lines of various nonmetals and the nonmetals can be determined by HeMIP-AES with a high sensitivity.
文摘Using a low power microwave generator and a surfatron discharge cavity, Ti3O5 was synthesized via the hydrogenation of TiO2 in surface wave induced microwave plasma. Besides, the chemical behavior of hydrogen in the plasma and its influence on the formation of Ti3O5 were preliminarily studied.
文摘Atmospheric pressure plasmas are not only powerful sources for excitation but also very good atomizers. In the early developing stage, the inductively coupled plasma (ICP) was investigated as an atomizer for atomic absorption spectrometry (AAS). A multiple pass system,a T-shaped plasma cell,and a long-path torch was used to increase the absorption path length. But all these ICP-AAS systems gave low sensitivities for most
基金funded by the Centre for Innovative Manufacturing in Ultra Precision of the Engineering and Physical Sciences Research Council,UK(Grant No.EP/I033491/1)the Centre for Doctoral Training in Ultra Precision Engineering of the Engineering and Physical Sciences Research Council,UK(Grant No.EP/K503241/1)+2 种基金the Science Foundation Ireland(SFI)(Grant No.15/RP/B3208)Irish Research Council(Grant No.CLNE/2018/1530)the National Natural Science Foundation of China(Grant No.51705462).
文摘Microwave induced plasma torches find wide applications in material and chemical analysis.Investigation of a coaxial electrode microwave induced plasma(CE–MIP)torch is conducted in this study,making it available for glass surface modification and polishing.A dedicated nozzle is designed to inject secondary gases into the main plasma jet.This study details the adaptation of a characterisation process for CE–MIP technology.Microwave spectrum analysis is used to create a polar plot of the microwave energy being emitted from the coaxial electrode,where the microwave energy couples with the gas to generate the plasma jet.Optical emission spectroscopy analysis is also employed to create spatial maps of the photonic intensity distribution within the plasma jet when different additional gases are injected into it.The CE–MIP torch is experimentally tested for surface energy modification on glass where it creates a super-hydrophilic surface.
文摘We studied experimentally the effect of microwaves （MWs） on the enhancement of plasma emission achieved by laser-induced breakdown spectroscopy （LIBS）. A laser plasma was generated on a calcium oxide pellet by a Nd：YAG laser （5 m J, 532 nm, 8 ns） in reduced-pressure argon surrounding gas. A MW radiation （400 W） was injected into the laser plasma via a loop antenna placed immediately above the laser plasma to enhance the plasma emission. The results confirmed that when tile electromagnetic field was introduced into the laser plasma region by the MWs, the lifetime of the plasma was extended from 50 to 500 μs, similar to the MW duration. Furthermore, the plasma temperature and electron density increased to approximately 10900 K and 1.5×10^18 cm^-3, respectively and the size of the plasma emission was extended to 15 mm in diameter. As a result, the emission intensity of Ca lines obtained using LIBS with MWs was enhanced by approximately 200 times compared to the case of LIBS without MWs.
