in order to elucidate the relationship between secretory otitis media (SOM) and allergy,the tympanogram and allergic skin test with house dust, mite, and Japanese cedar pollen allergen were made in 2702 pupils in Shir...in order to elucidate the relationship between secretory otitis media (SOM) and allergy,the tympanogram and allergic skin test with house dust, mite, and Japanese cedar pollen allergen were made in 2702 pupils in Shiraoi, Hokkaido, Japan. The correlation between the tympanogram type and the results of allergic skin was analyzed. This study suggests that there is no positive relationship between SOM and allergy.展开更多
The impedance and output power measurements of LDMOS transistors are always a problem due to their low impedance and lead widths.An improved thru-reflect-line(TRL) calibration algorithm for measuring the characteristi...The impedance and output power measurements of LDMOS transistors are always a problem due to their low impedance and lead widths.An improved thru-reflect-line(TRL) calibration algorithm for measuring the characteristics of L-band high power LDMOS transistors is presented.According to the TRL algorithm,the individual two-port S parameters of each fixture half can be obtained.By de-embedding these S parameters of the test fixture,an accurate calibration can be made.The improved TRL calibration algorithm is successfully utilized to measure the characteristics of an L-band LDMOS transistor with a 90 mm gate width.The impedance of the transistor is obtained,and output power at 1 dB compression point can reach as much as 109.4 W at 1.2 GHz, achieving 1.2 W/mm power density.From the results,it is seen that the presented TRL calibration algorithm works well.展开更多
Microstructures and corrosion of TiNbTaZrMo(Ti_(20)Nb_(20)Ta_(20)Zr_(20)Mo_(20))High-Entropy Alloy(HEA)were investigated in the Simu-lated Body Fluid(SBF).Microstructure of this alloy was investigated by X-Ray Difirac...Microstructures and corrosion of TiNbTaZrMo(Ti_(20)Nb_(20)Ta_(20)Zr_(20)Mo_(20))High-Entropy Alloy(HEA)were investigated in the Simu-lated Body Fluid(SBF).Microstructure of this alloy was investigated by X-Ray Difiraction(XRD)and Scanning Electron Microscopy(SEM)techniques.Our observations confirmed the presence of two bcc phases as the major matrix as well as another minor phase in themicrostructure of the alloy.Concentration of some elements,such as tantalum,niobium,and molybdenum in the dendritic branches and thepresence of zirconium and titanium in the inter-dendritic branches were clearly evidenced by Energy Dispersive X-ray(EDX)analysis.Given importance of corrosion of implant alloys in the human's body,elctrochemical impedance and cyclic polarization tests werepcerformed on the alloy in SBF.Through the corrosion tests,corrosion potential,current,and resistance were obtained as E_(corr)=-0.42 V,i_(corr)=0.34μA·cm^(-2),and R_(p)=27.44 k ohm·cm^(2),respectively.The results revealed that the rate of corrosion in TiNbTaZrMo HEA is about 26 times better than that of Ti_(6)Al_(4)V alloy.Also,both alloys had no pitting corrosion in the SBF solution.展开更多
文摘in order to elucidate the relationship between secretory otitis media (SOM) and allergy,the tympanogram and allergic skin test with house dust, mite, and Japanese cedar pollen allergen were made in 2702 pupils in Shiraoi, Hokkaido, Japan. The correlation between the tympanogram type and the results of allergic skin was analyzed. This study suggests that there is no positive relationship between SOM and allergy.
文摘The impedance and output power measurements of LDMOS transistors are always a problem due to their low impedance and lead widths.An improved thru-reflect-line(TRL) calibration algorithm for measuring the characteristics of L-band high power LDMOS transistors is presented.According to the TRL algorithm,the individual two-port S parameters of each fixture half can be obtained.By de-embedding these S parameters of the test fixture,an accurate calibration can be made.The improved TRL calibration algorithm is successfully utilized to measure the characteristics of an L-band LDMOS transistor with a 90 mm gate width.The impedance of the transistor is obtained,and output power at 1 dB compression point can reach as much as 109.4 W at 1.2 GHz, achieving 1.2 W/mm power density.From the results,it is seen that the presented TRL calibration algorithm works well.
文摘Microstructures and corrosion of TiNbTaZrMo(Ti_(20)Nb_(20)Ta_(20)Zr_(20)Mo_(20))High-Entropy Alloy(HEA)were investigated in the Simu-lated Body Fluid(SBF).Microstructure of this alloy was investigated by X-Ray Difiraction(XRD)and Scanning Electron Microscopy(SEM)techniques.Our observations confirmed the presence of two bcc phases as the major matrix as well as another minor phase in themicrostructure of the alloy.Concentration of some elements,such as tantalum,niobium,and molybdenum in the dendritic branches and thepresence of zirconium and titanium in the inter-dendritic branches were clearly evidenced by Energy Dispersive X-ray(EDX)analysis.Given importance of corrosion of implant alloys in the human's body,elctrochemical impedance and cyclic polarization tests werepcerformed on the alloy in SBF.Through the corrosion tests,corrosion potential,current,and resistance were obtained as E_(corr)=-0.42 V,i_(corr)=0.34μA·cm^(-2),and R_(p)=27.44 k ohm·cm^(2),respectively.The results revealed that the rate of corrosion in TiNbTaZrMo HEA is about 26 times better than that of Ti_(6)Al_(4)V alloy.Also,both alloys had no pitting corrosion in the SBF solution.
