Comparative Study on the Effect of Mongolian Medicine Euphorbia pekinensis and Pharbitidis Semen(Black)

[Objectives]To explore the difference of purgative effect of Mongolian medicine Euphorbia pekinensis and Pharbitidis Semen(black)by animal experiment,taking Euphorbia pekinensis and Pharbitidis Semen(black)as the research object.[Methods]Sixty Kunming mice were randomly divided into blank group(n=20),Euphorbia pekinensis group(n=20)and Pharbitidis Semen(black)group(n=20).After fasted but provided with free acess to drinking water for 3 d,the mice were intragastrically administered with drinking water,Euphorbia pekinensis test solution and Pharbitidis Semen(black)test solution,respectively.The mice were then placed separately in a mouse cage covered with filter paper for purgation test and intestinal propulsion test.[Results]The time of the first purgation in the Euphorbia pekinensis group and the Pharbitidis Semen(black)group was longer than that in the blank group(P<0.05).The total times of purgation and defecation within 5 h in the Euphorbia pekinensis group and the Pharbitidis Semen(black)group were higher than those in the blank group(P<0.05);the purgation index and intestinal propulsion rate in the Euphorbia pekinensis group and the Pharbitidis Semen(black)group were higher than those in the blank group(P<0.05).[Conclusions]The Mongolian medicine Euphorbia pekinensis was similar to Pharbitidis Semen(black)in purgation test and intestinal propulsion test,and could play a substitute role.

Multifunctional solar-blind ultraviolet photodetectors based on p-PCDTBT/n-Ga_(2)O_(3)heterojunction with high photoresponse

Solar-blind ultraviolet(UV)photodetectors based on p-organic/n-Ga_(2)O_(3) hybrid heterojunctions have attracted extensive attention recently.Herein,the multifunctional solar-blind photodetector based on p-type poly[N-90-heptadecanyl-2,7-carbazole-alt-5,5-(40,70-di-2-thienyl-20,10,30-benzothiadiazole)](PCDTBT)/n-type amorphous Ga_(2)O_(3)(a-Ga_(2)O_(3))is fabricated and investigated,which can work in the phototransistor mode coupling with self-powered mode.With the introduction of PCDTBT,the dark current of such the a-Ga_(2)O_(3)-based photodetector is decreased to 0.48 pA.Meanwhile,the photoresponse parameters of the a-Ga_(2)O_(3)-based photodetector in the phototransistor mode to solar-blind UV light are further increased,that is,responsivity(R),photo-detectivity(D*),and external quantum efficiency(EQE)enhanced to 187 A W^(-1),1.3×10^(16) Jones and 9.1×10^(4)% under the weak light intensity of 11μW cm^(-2),respectively.Thanks to the formation of the built-in field in the p-PCDTBT/n-Ga_(2)O_(3) type-Ⅱ heterojunction,the PCDTBT/Ga_(2)O_(3) multifunctional photodetector shows self-powered behavior.The responsivity of p-PCDTBT/n-Ga_(2)O_(3) multifunctional photodetector is 57.5 mA W^(-1) at zero bias.Such multifunctional p-n hybrid heterojunction-based photodetectors set the stage for realizing high-performance amorphous Ga_(2)O_(3) heterojunction-based photodetectors.

Parametric study on controllable growth of SrZrS_(3)thin films with good conductivity for photodetectors

SrZrS_(3)is a promising chalcogenide perovskite with unique advantages including high abundance of consisting elements,high chemical stability,strong light absorption above its direct band gap,excellent carrier transport ability.While unfortunately,due to the lack of breakthroughs in its thin film synthesis technique,its optoelectronic properties are not fully investigated,not to mention the device applications.In this work,large-area and uniform SrZrS_(3)thin film(5 cm×5 cm)was prepared by facile sputtering method,followed by a post-annealing treatment at a high temperature of 1000℃for 2–12 h under CS_(2)atmosphere.All SrZrS_(3)samples prepared adopt distorted orthorhombic structure with pnma space group and have high crystallinity.In addition,the band gap of SrZrS_(3)thin film is measured to be 2.29 eV,higher than that of the powder form(2.06 eV).Importantly,the light absorption coefficient of SrZrS_(3)thin film reaches over 105 cm^(−1),the carrier mobility is as high as 106 cm^(2)/(V∙s).The above advantages allow us to use the SrZrS_(3)thin film as photoactive layer for photodetector applications.Finally,a symmetrically structured photoconductive detector was fabricated,performing a high responsivity of 8 A/W(405 nm light excitation).These inspiring results promise the glorious application potential of SrZrS_(3)thin film in photodetectors,solar cells,other optoelectronic devices.