Aim To establish a method for determination of Ginkgo biloba L, its extractand preparations with HPLC fingerprints, so as to control the quality of the preparations. MethodsHPLC-DAD method was used to determine the co...Aim To establish a method for determination of Ginkgo biloba L, its extractand preparations with HPLC fingerprints, so as to control the quality of the preparations. MethodsHPLC-DAD method was used to determine the constituents in preparations. Diamonsil? C_(18) (200mm X 4.6 mm, 5 μm) was used as analytical column, and acetonitrile/KH_2PO_4 was used as mobilephase with gradient elu-tion. The column temperature was at 24 ℃. The HPLC profile of chemicalconstituents of control sample and preparations were analyzed using similarity software. Results Thefingerprints of different preparations from different companies were slightly different because ofthe different preparing procedures. Mean while, the fingerprints of different batches of the samepreparation from the same company were similar to each other and the technology of each preparationwas stable. Conclusion This method is accurate, reproducible , simple, and can be used as ananalytical method for the routine quality control of Ginkgo biloba preparations.展开更多
In this paper, we have investigated theoretically the high harmonic generation form helium atom in long wavelength driving regime at 2000 nm through solving time-dependent Schr6dinger equation. By adding a second harm...In this paper, we have investigated theoretically the high harmonic generation form helium atom in long wavelength driving regime at 2000 nm through solving time-dependent Schr6dinger equation. By adding a second harmonic pulse （1000 nm） and a UV attosecond pulse （200 nm） to the driving field, an efficient method for picking out and enhancing ionization path to generate high-yield supercontinuum harmonics is realized, and then an isolated sub-100 as pulse with a bandwidth of 190 eV is significantly obtained.展开更多
Coal storing and loading have much more influence on coal quality. In the paper, a goal programming model has been constructed to determine the ideal quantity extracting from stockpile and silos and a quality control ...Coal storing and loading have much more influence on coal quality. In the paper, a goal programming model has been constructed to determine the ideal quantity extracting from stockpile and silos and a quality control model is inferred under the guidance of maximum theory of dispersed number and practice methods are given to meet production demand, with which a coal mine has achieved a better tech-economic result.展开更多
A pot experiment was conducted to study the plant growth and fruit yields of cucumber （Cucumis sativus L.） on a greenhouse soil with or without inoculation of arbuscular mycorrhizal fungi （AMFs） and Fusarium oxysp...A pot experiment was conducted to study the plant growth and fruit yields of cucumber （Cucumis sativus L.） on a greenhouse soil with or without inoculation of arbuscular mycorrhizal fungi （AMFs） and Fusarium oxysporum f. sp, cucumerinum under unsterilized conditions. Two AMF inocula were tested： only one AMF strain Glomus caledonium 90036 and an AMF consortium mainly consisting of Glornus spp. and Acaulospora spp. There were four treatments including no inoculation （control）, inoculation with F. oxysporum but without mycorrhizae （FO）, inoculation with F. oxysporum and G. caledonium （FO＋M1）, and inoculation with F. oxysporum and the AMF consortium （FO＋M2）. Cucumber plants were harvested at weeks 3 and 9 after transplanting. Compared with the control, the FO treatment without AMF inoculation had less biomass both at weeks 3 and 9 （P 〈 0.05） and had higher incidence of Fusarium wilt and produced no cucumber fruit at week 9. Both FO＋M1 and FO＋M2 treatments had higher mycorrhizal colonization than the treatments which received no AMF inoculation at week 3 （P 〈 0.05）, but only the FO＋M2 treatment elevated plant biomass, decreased the incidence of Fusarium wilt, and improved cucumber yields to the same level as the control at week 9. The results indicated that the AMF consortium could suppress Fusarium wilt of cucumber and, therefore, showed potential as a biological control agent in greenhouse agroecosystems.展开更多
The alpine meadow ecosystem in Tibet is fragile and sensitive,and its carbon sink function with respect to climate change has become a matter of widespread concern.Therefore,this study aims to clarify the inter-annual...The alpine meadow ecosystem in Tibet is fragile and sensitive,and its carbon sink function with respect to climate change has become a matter of widespread concern.Therefore,this study aims to clarify the inter-annual variations(IAVs)in the carbon fluxes in an alpine meadow and to further quantify the contributions of the driving factors to the IAVs.Based on 7 years of flux data(2012-2018)and the corresponding climatic and biotic data,a set of look-up tables was used to separate and quantify the IAV sources.Furthermore,linear perturbation analyses were employed to quantify the contributions of each key factor.During 2012-2018,the net ecosystem productivity(NEP),gross primary productivity(GPP)and ecosystem respiration(Re)of this alpine meadow were 3.31±26.90,210.18±48.35 and 206.88±28.45 g C m^(-2) y^(-1),respectively,which indicated relatively large IAVs.When the contributions of climatic and biotic effects were distinguished and quantified,the dominant effects of biotic factors emerged.Additionally,negative interactions between climatic and biotic effects were detected.Among the climatic factors,only soil water content contributed relatively more to the IAVs and played a role in regulating the interactions between climatic and biotic effects.These results suggest that biotic effects must be carefully considered to reduce the uncertainties associated with future carbon flux estimates.展开更多
We study a production-inventory system having a machine, a storage facility. The demand for the product is governed by an Erlangian demand arrival process, where demand sizes are independent and identically distribute...We study a production-inventory system having a machine, a storage facility. The demand for the product is governed by an Erlangian demand arrival process, where demand sizes are independent and identically distributed random variables. A two-criticalnumber policy (m, M) is used to control a machine's setups and shutdowns, namely, a machine is shut down whenever the inventory level reaches M, and resumes operating only when the inventory level falls below the critical number m(m ≤ M). We obtain the steady state distribution of the inventory process and some performance measures of the process.展开更多
文摘Aim To establish a method for determination of Ginkgo biloba L, its extractand preparations with HPLC fingerprints, so as to control the quality of the preparations. MethodsHPLC-DAD method was used to determine the constituents in preparations. Diamonsil? C_(18) (200mm X 4.6 mm, 5 μm) was used as analytical column, and acetonitrile/KH_2PO_4 was used as mobilephase with gradient elu-tion. The column temperature was at 24 ℃. The HPLC profile of chemicalconstituents of control sample and preparations were analyzed using similarity software. Results Thefingerprints of different preparations from different companies were slightly different because ofthe different preparing procedures. Mean while, the fingerprints of different batches of the samepreparation from the same company were similar to each other and the technology of each preparationwas stable. Conclusion This method is accurate, reproducible , simple, and can be used as ananalytical method for the routine quality control of Ginkgo biloba preparations.
基金Supported by the Natural Science Foundation of Hubei Province under Grant No.2008CDB317
文摘In this paper, we have investigated theoretically the high harmonic generation form helium atom in long wavelength driving regime at 2000 nm through solving time-dependent Schr6dinger equation. By adding a second harmonic pulse （1000 nm） and a UV attosecond pulse （200 nm） to the driving field, an efficient method for picking out and enhancing ionization path to generate high-yield supercontinuum harmonics is realized, and then an isolated sub-100 as pulse with a bandwidth of 190 eV is significantly obtained.
文摘Coal storing and loading have much more influence on coal quality. In the paper, a goal programming model has been constructed to determine the ideal quantity extracting from stockpile and silos and a quality control model is inferred under the guidance of maximum theory of dispersed number and practice methods are given to meet production demand, with which a coal mine has achieved a better tech-economic result.
基金Supported by the Knowledge Innovation Program of the Chinese Academy of Sciences(Nos.ISSASIP0703,Kzcx2-yw-408,and Kzcx3-sw-439)
文摘A pot experiment was conducted to study the plant growth and fruit yields of cucumber （Cucumis sativus L.） on a greenhouse soil with or without inoculation of arbuscular mycorrhizal fungi （AMFs） and Fusarium oxysporum f. sp, cucumerinum under unsterilized conditions. Two AMF inocula were tested： only one AMF strain Glomus caledonium 90036 and an AMF consortium mainly consisting of Glornus spp. and Acaulospora spp. There were four treatments including no inoculation （control）, inoculation with F. oxysporum but without mycorrhizae （FO）, inoculation with F. oxysporum and G. caledonium （FO＋M1）, and inoculation with F. oxysporum and the AMF consortium （FO＋M2）. Cucumber plants were harvested at weeks 3 and 9 after transplanting. Compared with the control, the FO treatment without AMF inoculation had less biomass both at weeks 3 and 9 （P 〈 0.05） and had higher incidence of Fusarium wilt and produced no cucumber fruit at week 9. Both FO＋M1 and FO＋M2 treatments had higher mycorrhizal colonization than the treatments which received no AMF inoculation at week 3 （P 〈 0.05）, but only the FO＋M2 treatment elevated plant biomass, decreased the incidence of Fusarium wilt, and improved cucumber yields to the same level as the control at week 9. The results indicated that the AMF consortium could suppress Fusarium wilt of cucumber and, therefore, showed potential as a biological control agent in greenhouse agroecosystems.
基金the National Natural Science Foundation of China(41725003,31600362 and32061143037)a ChinaPostdoctoral Science Foundation funded project(2021M692230 and 2018M631819)the National Key Research and DevelopmentProgram of China(2017YFA0604801)and the Science and technology research project of Liaoning Provincial Department of Education(LSNQN201720).
文摘The alpine meadow ecosystem in Tibet is fragile and sensitive,and its carbon sink function with respect to climate change has become a matter of widespread concern.Therefore,this study aims to clarify the inter-annual variations(IAVs)in the carbon fluxes in an alpine meadow and to further quantify the contributions of the driving factors to the IAVs.Based on 7 years of flux data(2012-2018)and the corresponding climatic and biotic data,a set of look-up tables was used to separate and quantify the IAV sources.Furthermore,linear perturbation analyses were employed to quantify the contributions of each key factor.During 2012-2018,the net ecosystem productivity(NEP),gross primary productivity(GPP)and ecosystem respiration(Re)of this alpine meadow were 3.31±26.90,210.18±48.35 and 206.88±28.45 g C m^(-2) y^(-1),respectively,which indicated relatively large IAVs.When the contributions of climatic and biotic effects were distinguished and quantified,the dominant effects of biotic factors emerged.Additionally,negative interactions between climatic and biotic effects were detected.Among the climatic factors,only soil water content contributed relatively more to the IAVs and played a role in regulating the interactions between climatic and biotic effects.These results suggest that biotic effects must be carefully considered to reduce the uncertainties associated with future carbon flux estimates.
基金This research is supported by the National Natural Science Foundation of China (No. 19871093).
文摘We study a production-inventory system having a machine, a storage facility. The demand for the product is governed by an Erlangian demand arrival process, where demand sizes are independent and identically distributed random variables. A two-criticalnumber policy (m, M) is used to control a machine's setups and shutdowns, namely, a machine is shut down whenever the inventory level reaches M, and resumes operating only when the inventory level falls below the critical number m(m ≤ M). We obtain the steady state distribution of the inventory process and some performance measures of the process.
