Detecting remote homology proteins is a challenging problem for both basic research and drug development. Although there are a couple of methods to deal with this problem, the benchmark datasets based on which the exi...Detecting remote homology proteins is a challenging problem for both basic research and drug development. Although there are a couple of methods to deal with this problem, the benchmark datasets based on which the existing methods were trained and tested contain many high homologous samples as reflected by the fact that the cutoff threshold was set at 95%. In this study, we reconstructed the benchmark dataset by setting the threshold at 40%, meaning none of the proteins included in the benchmark dataset has more than 40% pairwise sequence identity with any other in the same subset. Using the new benchmark dataset, we proposed a new predictor called “dRHP-GreyFun” based on the grey modeling and functional domain approach. Rigorous cross-validations have indicated that the new predictor is superior to its counterparts in both enhancing success rates and reducing computational cost. The predictor can be downloaded from https://github.com/jcilwz/dRHP-GreyFun.展开更多
A series of different transition metals(V,Co,Cr,Mn,Fe,Ni,Cu and Zn) promoted H-ZSM-5 catalysts were prepared by impregnation method and characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM) and tra...A series of different transition metals(V,Co,Cr,Mn,Fe,Ni,Cu and Zn) promoted H-ZSM-5 catalysts were prepared by impregnation method and characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The catalytic activity of these catalysts was evaluated for the selective catalytic reduction(SCR) of NO with NH_3 as reductant in the presence of oxygen.The results revealed that the catalytic activity of Cu-ZSM-5 nanocatalyst for NO conversion to N_2 was 80%at 300 ℃,which was the best among various promoted metals.Design of experiments(DOEs) with Taguchi method was employed to optimize NH_3-SCR process parameters such as NH_3/NO ratio,O_2 concentration,and gas hourly space velocity(GHSV) over Cu-ZSM-5 nanocatalyst at 250 and 300 ℃.Results showed that the most important parameter in NH_3-SCR of NO is O_2 concentration;followed by NH_3/NO ratio and GHSV has little importance.The NO conversion to N_2 of 63.1%and 94.86%was observed at 250℃ and 300℃,respectively under the obtained optimum conditions.展开更多
Nanocrystalline Gd3Ga5O12:Eu3+ with cubic phase was prepared by a urea homogeneous precipitation method. X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), Fourier transform infrared spectrosc...Nanocrystalline Gd3Ga5O12:Eu3+ with cubic phase was prepared by a urea homogeneous precipitation method. X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), thermo-gravimetric and differential thermal analysis (TG-DTA) and photoluminescence spectra were used to characterize the samples. The effects of the initial solution pH value and urea content on the structure of the sample were studied. The XRD results show that pure phase Gd3Ga5O12 can be obtained at pH =6 and pH =8 of the initial solution. The average crystallite size can be calculated as in the range of 24~33 nm. The average crystallite size decreases with increasing molar ratio of urea to metal ion. The results of excitation spectra and emission spectra show that the emission peaks are ascribed to 5D0→7FJ transitions of Eu3+, and the magnetic dipole transition originated from 5D0 →7F1 of Eu3+ is the strongest; the broad excitation bands belong to change transfer band of Eu?O and the host absorption of Gd3Ga5O12. An efficient energy transfer occurs from Gd3+ to Eu3+.展开更多
With the aid of Meteorological Information Composite and Processing System (MICAPS), satellite wind vectors derived from the Geostationary Meteorological Statellite-5 (GMS-5) and retrieved by National Satellite Meteor...With the aid of Meteorological Information Composite and Processing System (MICAPS), satellite wind vectors derived from the Geostationary Meteorological Statellite-5 (GMS-5) and retrieved by National Satellite Meteorology Center of China (NSMC) can be obtained. Based on the nudging method built in the fifth-generation Mesoscale Model (MM5) of Pennsylvania State University and Na- tional Center for Atmospheric Research, a data preprocessor is developed to convert these satellite wind vectors to those with specified format required in MM5. To examine the data preprocessor and evaluate the impact of satellite winds from GMS-5 on MM5 simulations, a series of numerical experimental fore- casts consisting of four typhoon cases in 2002 are designed and implemented. The results show that the preprocessor can process satellite winds smoothly and MM5 model runs successfully with a little extra computational load during ingesting these winds, and that assimilation of satellite winds by MM5 nudging method can obviously improve typhoon track forecast but contributes a little to typhoon intensity forecast. The impact of the satellite winds depends heavily upon whether the typhoon bogussing scheme in MM5 was turned on or not. The data preprocessor developed in this paper not only can treat GMS-5 satellite winds but also has capability with little modification to process derived winds from other geostationary satellites.展开更多
The purpose of this work is to explore the effects of the introduction methods of Ce^4+and Zr^4+on the physicochemical properties,activity,and K tolerance of V2 O5-WO3/TiO2 catalyst for the selective catalytic reducti...The purpose of this work is to explore the effects of the introduction methods of Ce^4+and Zr^4+on the physicochemical properties,activity,and K tolerance of V2 O5-WO3/TiO2 catalyst for the selective catalytic reduction of NOx by NH3.Four different methods,namely pre-impregnation,post-impregnation,coimpregnation,and co-precipitation,were used to synthesize a series of V2 O5-WO3-TiO2-CeO2-ZrO2 catalysts.The catalysts were characterized by XRD,BET,NH3-TPD,XPS,and H2-TPR techniques.Moreover,the activity and anti-K poisoning performance were tested by an NH3-SCR model reaction.The results show that the introduction of Ce^4+and Zr^4+can improve the catalytic performance of V2O5-WO3/TiO2 catalyst,but the impregnation method cannot enhance the anti-K poisoning performance.Ce^4+and Zr^4+introduced by co-precipitation method can effectively improve the tolerance of K,which is mainly due to the incorporation of Ce^4+and Zr^4+into TiO2 lattice to form a uniform TiO2-CeO2-ZrO2 solid solution,resulting in the optimal surface acidity and redox performance,and reducing the decreases caused by Kpoisoning.Furthermore,based on the best introduction method,we further optimized the molar ratio of Ce^4+/Zr^4+,It is found that the catalyst exhibits the best anti-K poisoning performance when the molar ratio of Ce^4+/Zr^4+is 2:1.展开更多
In this current minireview, the cradle of the “5-steps rule” or “5-step rules”, along with its essence and advances, has been recalled. Born in 2011, its impacts on molecular biology are both substantial and rapid...In this current minireview, the cradle of the “5-steps rule” or “5-step rules”, along with its essence and advances, has been recalled. Born in 2011, its impacts on molecular biology are both substantial and rapid, fully indicating the “5-steps rule” is no double a remarkable and profound milestone in molecular biology.展开更多
Since the 5-steps rule was proposed in 2011, it has been widely used in many areas of molecular biology, both theoretical and experimental. It can be even used to deal with the commercial problems and bank systems, as...Since the 5-steps rule was proposed in 2011, it has been widely used in many areas of molecular biology, both theoretical and experimental. It can be even used to deal with the commercial problems and bank systems, as well as material science systems. Just like the machine-learning algorithms, it is the jade for nearly all the statistical systems.展开更多
In this short review paper, the significant and profound impacts of the 5-steps rule have <span style="mso-bookmark:OLE_LINK2;"><span style="mso-bookmark:OLE_LINK1;"><span lang="...In this short review paper, the significant and profound impacts of the 5-steps rule have <span style="mso-bookmark:OLE_LINK2;"><span style="mso-bookmark:OLE_LINK1;"><span lang="EN-US" style="line-height: 97%;font-family:;" capt",serif;font-size:11pt;"="" pro="" minion="">been briefly recalled with crystal clear convincingness.</span></span></span>展开更多
In this work,various Co_(3)O_(4)-ZSM-5 catalysts were prepared by the microwave hydrothermal method(MH-Co_(3)O_(4)@ZSM-5),dynamic hydrothermal method(DH-Co_(3)O_(4)@ZSM-5),and conventio nal hydrothermal method(CH-Co_(...In this work,various Co_(3)O_(4)-ZSM-5 catalysts were prepared by the microwave hydrothermal method(MH-Co_(3)O_(4)@ZSM-5),dynamic hydrothermal method(DH-Co_(3)O_(4)@ZSM-5),and conventio nal hydrothermal method(CH-Co_(3)O_(4)/ZSM-5).Their catalytic oxidation of dichloromethane(DCM)was analyzed.Detailed characterizations such as X-ray diffractometer(XRD),scanning microscopy(SEM),X-ray photoelectron spectroscopy(XPS),Brunauer-Emmett-Teller(BET),H2 temperature-programmed reduction(H2-TPR),temperature-programmed desorption of O_(2)(O_(2)-TPD),temperature-programmed desorption of NH_(3)(NH_(3)-TPD),diffuse reflectance infrared Fourier-transform spectra with NH_(3)molecules(NH_(3)-DRIFT),and temperature-programmed surface reaction(TPSR)were performed.Results showed that with the assistance of microwave,MH-Co_(3)O_(4)@ZSM-5 formed a uniform core-shell structure,while the other two samples did not.MH-Co_(3)O_(4)@ZSM-5 possessed rich surface adsorbed oxygen species,higher ratio of Co^(3+)/Co^(2+),strong acidity,high reducibility,and oxygen mobility among the three Co_(3)O_(4)-ZSM-5 catalysts,which was beneficial for the improvement of DCM oxidation.In the oxidation of dichloromethane,MH-Co_(3)O_(4)@ZSM-5 presented the best activity and mineralization,which was consistent with the characterizations results.Meanwhile,according to the TPSR test,HCl or Cl_(2)removal from the catalyst surface was also promoted in MH-Co_(3)O_(4)@ZSM-5 by their abundant Bronsted acid sites and the promotion of Deacon reaction by Co_(3)O_(4)or the synergistic effect of Co_(3)O_(4)and ZSM-5.According to the results of in situ DRIFT studies,a possible reaction pathway of DCM oxidation was proposed over the MH-Co_(3)O_(4)@ZSM-5 catalysts.展开更多
The single crystal scintillating optical fibers acting as the scintillators and light conductors show potential application in scintillating fiber array detectors with high spatial resolution.In this paper we report t...The single crystal scintillating optical fibers acting as the scintillators and light conductors show potential application in scintillating fiber array detectors with high spatial resolution.In this paper we report the growth of 0.2 at%Ce:Y_(3)Al_(5)O_(12) single crystal fiber.The crystalline phase,surface morphology of the axialsection and cro ss-section,optical and scintillation properties of the as-grown fiber were investigated.The Ce:Y_(3)Al_(5)O_(12) single crystal fiber has a pure YAG phase,a uniform distribution of cerium in the axialsection and cross-section surface.Emission spectrum is composed of broad bands ranging from 440 to700 nm.In addition,the single crystal fiber has a high light yield of 26115±2000 photons/MeV,low energy resolution of 9.44%@662 keV and decay time of a fast component of 78 ns and a slow component of 301 ns.The intensity ratio of fast to slow components is roughly 8:1.展开更多
The sixth Data Release （DR6） of the Sloan Digital Sky Survey （SDSS） provides more photometric regions, new features and more accurate data around globular cluster Palomar 5. A new method, Back Propagation Neural N...The sixth Data Release （DR6） of the Sloan Digital Sky Survey （SDSS） provides more photometric regions, new features and more accurate data around globular cluster Palomar 5. A new method, Back Propagation Neural Network （BPNN）, is used to estimate the cluster membership probability in order to detect its tidal tails. Cluster and field stars, used for training the networks, are extracted over a 40 × 20 deg^2 field by color-magnitude diagrams （CMDs）. The best BPNNs with two hidden layers and a Levenberg-Marquardt （LM） training algorithm are determined by the chosen cluster and field samples. The membership probabilities of stars in the whole field are obtained with the BPNNs, and contour maps of the probability distribution show that a tail extends .5.42° to the north of the cluster and another tail extends 3.77° to the south. The tails are similar to those detected by Odenkirchen et al., but no more debris from the cluster is found to the northeast in the sky. The radial density profiles are investigated both along the tails and near the cluster center. Quite a few substructures are discovered in the tails. The number density profile of the cluster is fitted with the King model and the tidal radius is determined as 14.28＇. However, the King model cannot fit the observed profile at the outer regions （R 〉 8＇） because of the tidal tails generated by the tidal force. Luminosity functions of the cluster and the tidal tails are calculated, which confirm that the tails originate from Palomar 5.展开更多
The mean activity coefficient of 5, 10,15 , 20-tetrakis (P-methoxyl-O-sulfophenyl)porphyrin sodium in dilute aqueous solution has been determined in the modality range 0. 00547-0. 08871 mol · kg-1at 273. 2 K by t...The mean activity coefficient of 5, 10,15 , 20-tetrakis (P-methoxyl-O-sulfophenyl)porphyrin sodium in dilute aqueous solution has been determined in the modality range 0. 00547-0. 08871 mol · kg-1at 273. 2 K by the freezing-point depression method . The results of γ± are 0. 9945-0. 7695, it is in close agreement with that by isopiestic method.展开更多
Li[Li1/3Ti5/3O4] spinel-framework structure material is a kind of great interest for negative electrodes in energy storage cell. The synthesis of nanocrystalline Li[Li1/3Ti5/3O4] by sol-gel method using inorganic comp...Li[Li1/3Ti5/3O4] spinel-framework structure material is a kind of great interest for negative electrodes in energy storage cell. The synthesis of nanocrystalline Li[Li1/3Ti5/3O4] by sol-gel method using inorganic compounds and citric acid is developed, and single phase powder is obtained above 700 ℃. The electrochemical performances (of Li[Li1/3Ti5/3O4]) cathodes in lithium cell are studied. Special capacities are 131 mA·h·g-1 at 0.5C rate and 154 mA·h·g-1 at 0.1C in cycle test. No passivation layer is formed on Li[Li1/3Ti5/3O4] anode in lithium ion battery, and it is much safer than lithium metal and carbonaceous anodes. Faradic impedance in the charged cell is remarkably higher than that in discharged state, which is caused by distinct conductivities of Li[Li1/3Ti5/3O4] and (Li2[Li1/3Ti5/3O4].)展开更多
4,4-Dialkyl-2-oxazolin-5-ones are prepared by one step reaction of 2-oxazolin-5-one with the magnesium methyl carbonate(MMC)and alkyIhalides.It is a novel and convenient method for synthesis of α, Υ-disubstitutcd α...4,4-Dialkyl-2-oxazolin-5-ones are prepared by one step reaction of 2-oxazolin-5-one with the magnesium methyl carbonate(MMC)and alkyIhalides.It is a novel and convenient method for synthesis of α, Υ-disubstitutcd α-amino acid by hydrolysis of 4,4-dialkyl-2-oxazolin-5-ones.展开更多
In this letter, the φ^6 ＋ φ^5 model in （D ＋ 1） dimensions can be solved by a truncated series method. A series of solitary solutions of the φ^6 ＋ φ^5 model in （D ＋ 1） dimensions have be obtained.
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
文摘Detecting remote homology proteins is a challenging problem for both basic research and drug development. Although there are a couple of methods to deal with this problem, the benchmark datasets based on which the existing methods were trained and tested contain many high homologous samples as reflected by the fact that the cutoff threshold was set at 95%. In this study, we reconstructed the benchmark dataset by setting the threshold at 40%, meaning none of the proteins included in the benchmark dataset has more than 40% pairwise sequence identity with any other in the same subset. Using the new benchmark dataset, we proposed a new predictor called “dRHP-GreyFun” based on the grey modeling and functional domain approach. Rigorous cross-validations have indicated that the new predictor is superior to its counterparts in both enhancing success rates and reducing computational cost. The predictor can be downloaded from https://github.com/jcilwz/dRHP-GreyFun.
基金financial support from University of Tabriz and Iranian Nanotechnology Initiative
文摘A series of different transition metals(V,Co,Cr,Mn,Fe,Ni,Cu and Zn) promoted H-ZSM-5 catalysts were prepared by impregnation method and characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The catalytic activity of these catalysts was evaluated for the selective catalytic reduction(SCR) of NO with NH_3 as reductant in the presence of oxygen.The results revealed that the catalytic activity of Cu-ZSM-5 nanocatalyst for NO conversion to N_2 was 80%at 300 ℃,which was the best among various promoted metals.Design of experiments(DOEs) with Taguchi method was employed to optimize NH_3-SCR process parameters such as NH_3/NO ratio,O_2 concentration,and gas hourly space velocity(GHSV) over Cu-ZSM-5 nanocatalyst at 250 and 300 ℃.Results showed that the most important parameter in NH_3-SCR of NO is O_2 concentration;followed by NH_3/NO ratio and GHSV has little importance.The NO conversion to N_2 of 63.1%and 94.86%was observed at 250℃ and 300℃,respectively under the obtained optimum conditions.
基金financially supported by the Science and Technology Research Project of Department of Education of Liaoning Province,China(No.L2011063)
文摘Nanocrystalline Gd3Ga5O12:Eu3+ with cubic phase was prepared by a urea homogeneous precipitation method. X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), thermo-gravimetric and differential thermal analysis (TG-DTA) and photoluminescence spectra were used to characterize the samples. The effects of the initial solution pH value and urea content on the structure of the sample were studied. The XRD results show that pure phase Gd3Ga5O12 can be obtained at pH =6 and pH =8 of the initial solution. The average crystallite size can be calculated as in the range of 24~33 nm. The average crystallite size decreases with increasing molar ratio of urea to metal ion. The results of excitation spectra and emission spectra show that the emission peaks are ascribed to 5D0→7FJ transitions of Eu3+, and the magnetic dipole transition originated from 5D0 →7F1 of Eu3+ is the strongest; the broad excitation bands belong to change transfer band of Eu?O and the host absorption of Gd3Ga5O12. An efficient energy transfer occurs from Gd3+ to Eu3+.
基金Supported by Major State Basic Research Development Program of China (973 Program, No.2005CB4223-01) and Key Technologies R & D Program of China (No.2001BA603B-01).
文摘With the aid of Meteorological Information Composite and Processing System (MICAPS), satellite wind vectors derived from the Geostationary Meteorological Statellite-5 (GMS-5) and retrieved by National Satellite Meteorology Center of China (NSMC) can be obtained. Based on the nudging method built in the fifth-generation Mesoscale Model (MM5) of Pennsylvania State University and Na- tional Center for Atmospheric Research, a data preprocessor is developed to convert these satellite wind vectors to those with specified format required in MM5. To examine the data preprocessor and evaluate the impact of satellite winds from GMS-5 on MM5 simulations, a series of numerical experimental fore- casts consisting of four typhoon cases in 2002 are designed and implemented. The results show that the preprocessor can process satellite winds smoothly and MM5 model runs successfully with a little extra computational load during ingesting these winds, and that assimilation of satellite winds by MM5 nudging method can obviously improve typhoon track forecast but contributes a little to typhoon intensity forecast. The impact of the satellite winds depends heavily upon whether the typhoon bogussing scheme in MM5 was turned on or not. The data preprocessor developed in this paper not only can treat GMS-5 satellite winds but also has capability with little modification to process derived winds from other geostationary satellites.
基金Project supported by the National Natural Science Foundation of China(21876168)the Key Projects for Common Key Technology Innovation in Key Industries in Chongqing(cstc2016zdcy-ztzx0020-01)+1 种基金Youth Innovation Promotion Association CAS(2019376)the Graduate Innovation Project of Chongqing Technology and Business University(yjscxx201803-028-22)。
文摘The purpose of this work is to explore the effects of the introduction methods of Ce^4+and Zr^4+on the physicochemical properties,activity,and K tolerance of V2 O5-WO3/TiO2 catalyst for the selective catalytic reduction of NOx by NH3.Four different methods,namely pre-impregnation,post-impregnation,coimpregnation,and co-precipitation,were used to synthesize a series of V2 O5-WO3-TiO2-CeO2-ZrO2 catalysts.The catalysts were characterized by XRD,BET,NH3-TPD,XPS,and H2-TPR techniques.Moreover,the activity and anti-K poisoning performance were tested by an NH3-SCR model reaction.The results show that the introduction of Ce^4+and Zr^4+can improve the catalytic performance of V2O5-WO3/TiO2 catalyst,but the impregnation method cannot enhance the anti-K poisoning performance.Ce^4+and Zr^4+introduced by co-precipitation method can effectively improve the tolerance of K,which is mainly due to the incorporation of Ce^4+and Zr^4+into TiO2 lattice to form a uniform TiO2-CeO2-ZrO2 solid solution,resulting in the optimal surface acidity and redox performance,and reducing the decreases caused by Kpoisoning.Furthermore,based on the best introduction method,we further optimized the molar ratio of Ce^4+/Zr^4+,It is found that the catalyst exhibits the best anti-K poisoning performance when the molar ratio of Ce^4+/Zr^4+is 2:1.
文摘In this current minireview, the cradle of the “5-steps rule” or “5-step rules”, along with its essence and advances, has been recalled. Born in 2011, its impacts on molecular biology are both substantial and rapid, fully indicating the “5-steps rule” is no double a remarkable and profound milestone in molecular biology.
文摘Since the 5-steps rule was proposed in 2011, it has been widely used in many areas of molecular biology, both theoretical and experimental. It can be even used to deal with the commercial problems and bank systems, as well as material science systems. Just like the machine-learning algorithms, it is the jade for nearly all the statistical systems.
文摘In this short review paper, the significant and profound impacts of the 5-steps rule have <span style="mso-bookmark:OLE_LINK2;"><span style="mso-bookmark:OLE_LINK1;"><span lang="EN-US" style="line-height: 97%;font-family:;" capt",serif;font-size:11pt;"="" pro="" minion="">been briefly recalled with crystal clear convincingness.</span></span></span>
基金financially supported by the National Natural Science Foundation of China(No.51708492)National Key Research and Development Plan of China(No.2016YFC0204700)+1 种基金Zhejiang Provincial"151"Talents Programthe Program for Zhejiang Leading Team of S&T Innovation(No.2013TD07)。
文摘In this work,various Co_(3)O_(4)-ZSM-5 catalysts were prepared by the microwave hydrothermal method(MH-Co_(3)O_(4)@ZSM-5),dynamic hydrothermal method(DH-Co_(3)O_(4)@ZSM-5),and conventio nal hydrothermal method(CH-Co_(3)O_(4)/ZSM-5).Their catalytic oxidation of dichloromethane(DCM)was analyzed.Detailed characterizations such as X-ray diffractometer(XRD),scanning microscopy(SEM),X-ray photoelectron spectroscopy(XPS),Brunauer-Emmett-Teller(BET),H2 temperature-programmed reduction(H2-TPR),temperature-programmed desorption of O_(2)(O_(2)-TPD),temperature-programmed desorption of NH_(3)(NH_(3)-TPD),diffuse reflectance infrared Fourier-transform spectra with NH_(3)molecules(NH_(3)-DRIFT),and temperature-programmed surface reaction(TPSR)were performed.Results showed that with the assistance of microwave,MH-Co_(3)O_(4)@ZSM-5 formed a uniform core-shell structure,while the other two samples did not.MH-Co_(3)O_(4)@ZSM-5 possessed rich surface adsorbed oxygen species,higher ratio of Co^(3+)/Co^(2+),strong acidity,high reducibility,and oxygen mobility among the three Co_(3)O_(4)-ZSM-5 catalysts,which was beneficial for the improvement of DCM oxidation.In the oxidation of dichloromethane,MH-Co_(3)O_(4)@ZSM-5 presented the best activity and mineralization,which was consistent with the characterizations results.Meanwhile,according to the TPSR test,HCl or Cl_(2)removal from the catalyst surface was also promoted in MH-Co_(3)O_(4)@ZSM-5 by their abundant Bronsted acid sites and the promotion of Deacon reaction by Co_(3)O_(4)or the synergistic effect of Co_(3)O_(4)and ZSM-5.According to the results of in situ DRIFT studies,a possible reaction pathway of DCM oxidation was proposed over the MH-Co_(3)O_(4)@ZSM-5 catalysts.
基金Project supported by the Instrument Developing Project of the Chinese Academy of Sciences(YJKYYQ20170019)International Partnership Program of Chinese Academy of Sciences(121631KYSB20180045)+2 种基金National Natural Science Foundation of China(51872309,U1832106,62005302)Science and Technology Commission of Shanghai Municipality(20511107400,ZJ2020-ZD-005)Science Foundation for Youth Scholar of State Key Laboratory of High Performance Ceramics and Superfine Micro structures(SKL201904)。
文摘The single crystal scintillating optical fibers acting as the scintillators and light conductors show potential application in scintillating fiber array detectors with high spatial resolution.In this paper we report the growth of 0.2 at%Ce:Y_(3)Al_(5)O_(12) single crystal fiber.The crystalline phase,surface morphology of the axialsection and cro ss-section,optical and scintillation properties of the as-grown fiber were investigated.The Ce:Y_(3)Al_(5)O_(12) single crystal fiber has a pure YAG phase,a uniform distribution of cerium in the axialsection and cross-section surface.Emission spectrum is composed of broad bands ranging from 440 to700 nm.In addition,the single crystal fiber has a high light yield of 26115±2000 photons/MeV,low energy resolution of 9.44%@662 keV and decay time of a fast component of 78 ns and a slow component of 301 ns.The intensity ratio of fast to slow components is roughly 8:1.
基金Supported by the National Natural Science Foundation of China
文摘The sixth Data Release （DR6） of the Sloan Digital Sky Survey （SDSS） provides more photometric regions, new features and more accurate data around globular cluster Palomar 5. A new method, Back Propagation Neural Network （BPNN）, is used to estimate the cluster membership probability in order to detect its tidal tails. Cluster and field stars, used for training the networks, are extracted over a 40 × 20 deg^2 field by color-magnitude diagrams （CMDs）. The best BPNNs with two hidden layers and a Levenberg-Marquardt （LM） training algorithm are determined by the chosen cluster and field samples. The membership probabilities of stars in the whole field are obtained with the BPNNs, and contour maps of the probability distribution show that a tail extends .5.42° to the north of the cluster and another tail extends 3.77° to the south. The tails are similar to those detected by Odenkirchen et al., but no more debris from the cluster is found to the northeast in the sky. The radial density profiles are investigated both along the tails and near the cluster center. Quite a few substructures are discovered in the tails. The number density profile of the cluster is fitted with the King model and the tidal radius is determined as 14.28＇. However, the King model cannot fit the observed profile at the outer regions （R 〉 8＇） because of the tidal tails generated by the tidal force. Luminosity functions of the cluster and the tidal tails are calculated, which confirm that the tails originate from Palomar 5.
文摘The mean activity coefficient of 5, 10,15 , 20-tetrakis (P-methoxyl-O-sulfophenyl)porphyrin sodium in dilute aqueous solution has been determined in the modality range 0. 00547-0. 08871 mol · kg-1at 273. 2 K by the freezing-point depression method . The results of γ± are 0. 9945-0. 7695, it is in close agreement with that by isopiestic method.
文摘Li[Li1/3Ti5/3O4] spinel-framework structure material is a kind of great interest for negative electrodes in energy storage cell. The synthesis of nanocrystalline Li[Li1/3Ti5/3O4] by sol-gel method using inorganic compounds and citric acid is developed, and single phase powder is obtained above 700 ℃. The electrochemical performances (of Li[Li1/3Ti5/3O4]) cathodes in lithium cell are studied. Special capacities are 131 mA·h·g-1 at 0.5C rate and 154 mA·h·g-1 at 0.1C in cycle test. No passivation layer is formed on Li[Li1/3Ti5/3O4] anode in lithium ion battery, and it is much safer than lithium metal and carbonaceous anodes. Faradic impedance in the charged cell is remarkably higher than that in discharged state, which is caused by distinct conductivities of Li[Li1/3Ti5/3O4] and (Li2[Li1/3Ti5/3O4].)
文摘4,4-Dialkyl-2-oxazolin-5-ones are prepared by one step reaction of 2-oxazolin-5-one with the magnesium methyl carbonate(MMC)and alkyIhalides.It is a novel and convenient method for synthesis of α, Υ-disubstitutcd α-amino acid by hydrolysis of 4,4-dialkyl-2-oxazolin-5-ones.
基金The project supported by National Natural Science Foundation of China under Grant No. 10575026.Acknowledgments The author thanks Prof. S.Y. Lou for helpful discussions.
文摘In this letter, the φ^6 ＋ φ^5 model in （D ＋ 1） dimensions can be solved by a truncated series method. A series of solitary solutions of the φ^6 ＋ φ^5 model in （D ＋ 1） dimensions have be obtained.
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.
