We present a simple hot press-based method for processing La(Fe,Si)13-based compounds consisting of La–Fe–Co–Si–C particles and phenolic resin. The magnetic entropy change △S per unit mass for the La Fe_(10.87)Co...We present a simple hot press-based method for processing La(Fe,Si)13-based compounds consisting of La–Fe–Co–Si–C particles and phenolic resin. The magnetic entropy change △S per unit mass for the La Fe_(10.87)Co_(0.63)Si_(1.5)C_(0.2)/phenolic resin compounds have nearly the same magnitude with the base materials. With the content of phenolic resin of 5.0 wt%, the compound conductivity is 3.13 W·m^(-1)·K^(-1). In order to measure the cooling performance of La(Fe,Si)13-based compounds,the La(Fe_(11.6-x)Co_(x))Si_(1.4)C_(0.15)(x =0.60, 0.65, 0.75, 0.80, 0.85)/phenolic resin compounds were pressed into thin plates and tested in a hybrid refrigerator that combines the active magnetic refrigeration effect with the Stirling cycle refrigeration effect. The test results showed that a maximum cooling power of 41 W was achieved over a temperature span of 30 K.展开更多
Photocatalysis of CH3OH on the ZnO(0001) surface has been investigated by using temperature-programmed desorption (TPD) method with a 266 nm laser light. TPD results show that part of the CH3OH adsorbed on ZnO(0001) s...Photocatalysis of CH3OH on the ZnO(0001) surface has been investigated by using temperature-programmed desorption (TPD) method with a 266 nm laser light. TPD results show that part of the CH3OH adsorbed on ZnO(0001) surface are in molecular form, while others are dissociated. The thermal reaction products of H2, CH3·, H2O, CO, CH2O, CO2 and CH3OH have been detected. Experiments with the UV laser light indicate that the irradiation can promote the dissociation of CH3OH/CH3O· to form CH2O, which can be fu- ture converted to HCOO- during heating or illumination. The reaction between CH3OHZn and OHad can form the H2O molecule at the Zn site. Both temperature and illumination promote the desorption of CH3· from CH3O·. The research provides a new insight into the photocatalytic reaction mechanism of CH3OH on ZnO(0001).展开更多
Developing the multifunctional nanocarriers for long-term drug release and luminescence traceability is a challenging assignment.In this task,we designed a novel nanoplatform for long-term and luminescence trackable c...Developing the multifunctional nanocarriers for long-term drug release and luminescence traceability is a challenging assignment.In this task,we designed a novel nanoplatform for long-term and luminescence trackable chemotherapy,which is prepared via a hollow ZIF-8(where ZIF is zeolitic imidazolate frameworks)coated by the Eu^(3+)-doped mesoporous silica(ZIF-8@mesoporous silica).The hollow ZIF-8 is used as a drug library for loading the anticancer drug,and the pH-sensitive properties of ZIF-8 can targeted-release drugs in the tumor and cut down the poisonousness of drugs to normal cells.The shell layer of mesoporous silica can achieve the long-term drug release,which solves the problem of short drug circulation time in the body,reduces the drug administration frequency,and improves the therapeutic effect.Notably,the ZIF-8@mesoporous+doxorubicin(DOX)is injected only once during the 14-day chemotherapy.In addition,Eu^(3+)doped in mesoporous silica ensures luminescence tracking and detection of drug pathways in living cells.Hence,this nanoplatform provides a whole new strategy for the longterm treatment of tumors.展开更多
Thermo-mechanical process and continuous cooling process were carried out on 20CrNi2MoV steel. Three cooling rates were implemented to optimize the mechanical properties. The microstructure evolution, precipitation be...Thermo-mechanical process and continuous cooling process were carried out on 20CrNi2MoV steel. Three cooling rates were implemented to optimize the mechanical properties. The microstructure evolution, precipitation behavior, and strengthening mechanisms were systematically investigated, and the fracture mechanisms were analyzed via combination of impact fracture morphologies and deflection-load curves. The experimental results indicate that the transformed microstructure of experimental steel is all complex consisting of granular bainitic ferrite and bainitic ferrite with dispersed martensite/austenite （M/A） constituents in the matrix at cooling rates of 13, 21, and 29 ℃/s. When the cooling rate increases, the grain of the steel is obviously refined. The sizes of the bainitic ferrite are 5.8, 4.7, and 3.1 μm under cooling rates of 13, 21, and 29 ℃/s, respectively. The refinement of the bainitic ferrite plays a dominant role in strength increasing and also contributes to high crack propagation energy. However, the morphologies of M/A constituents obtained under different cooling rates contribute to different crack initiation energies and then affect the impact property.展开更多
Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities. They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan, and Sarga...Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities. They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan, and Sargassum gramini- folium turn (SG), Sargassum thunbergii (STH), and Laminaria japonica (LJ) from China. The ethanol extracts of these brown seaweeds were optimized at 85% (v/v) ethanol for the maximum yield of phlorotannin, an inhibitor against hyaluronidase. Total phlorotannins contained in the crude extracts were measured as 1.71% (SG), 0.74% (STH), 0.97% (LJ), 3.30% (SC), and 5.06% (ST). The 50% inhibitory concentrations (IC50) of Pakistani SC and ST were 109.5 and 21 μg/ml, respectively, lower than those of Chinese SG, STH, and LJ (134, 269, and 148 μg/ml, respectively). An antiallergic drug, disodium cromoglycate (DSCG), had an IC50=39 μg/ml, and a natural inhibitor of hyaluronidase, catechin, had an IC50=20 μg/ml. The IC50 of ST extract was found similar to that of catechin (21 vs 20 μg/ml) and lower than that of DSCG (21 vs 39 μg/ml). This suggests that ST is a potent inhibitor of hyaluronidase, indicating a promising future development of natural antiallergic medicines or functional foods.展开更多
In order to optimize the production process, improve the production efficiency and accelerate the development and application of the domestic dual-phase steel, the effects of heat treatment process parameters on micro...In order to optimize the production process, improve the production efficiency and accelerate the development and application of the domestic dual-phase steel, the effects of heat treatment process parameters on microstructure and mechanical properties of DP440 cold rolled strip were studied by the CAS-300 simulated continuous annealing equipment. When the heating rate increased from 5 to 100 ℃/s, both the tensile strength and yield strength increased because of the decreased grain size. When the intercritical annealing temperature increased from 780 to 850 ℃, the martensite content decreased so that the tensile strength decreased first, then increased, and the yield strength increased. When the rapid cooling rate increased from 25 to 100 ℃/s, because the martensite content increased, the tensile strength increased, while the yield strength decreased. When the overaging temperature increased from 260 to 400 ℃, the tensile strength decreased, while the yield strength increased. When the overaging time increased from 240 to 480 s, the tensile strength decreased a little, while the yield strength increased a little.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 52171054 and 52171195)the National Natural Science Foundation for Distinguished Young Scholars (Grant No. 51925605)。
文摘We present a simple hot press-based method for processing La(Fe,Si)13-based compounds consisting of La–Fe–Co–Si–C particles and phenolic resin. The magnetic entropy change △S per unit mass for the La Fe_(10.87)Co_(0.63)Si_(1.5)C_(0.2)/phenolic resin compounds have nearly the same magnitude with the base materials. With the content of phenolic resin of 5.0 wt%, the compound conductivity is 3.13 W·m^(-1)·K^(-1). In order to measure the cooling performance of La(Fe,Si)13-based compounds,the La(Fe_(11.6-x)Co_(x))Si_(1.4)C_(0.15)(x =0.60, 0.65, 0.75, 0.80, 0.85)/phenolic resin compounds were pressed into thin plates and tested in a hybrid refrigerator that combines the active magnetic refrigeration effect with the Stirling cycle refrigeration effect. The test results showed that a maximum cooling power of 41 W was achieved over a temperature span of 30 K.
基金This work was supported by the National Key R&D Program of China(No.2017YFF0104500)the National Natural Science Foundation of China(No.21590802 and No.21473173)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB17000000).
基金National Key R&D Program of China (No.2016YFF0200500), the National Natural Science Foundation of China (No.21473173, No.21590802, and No.21403207), the Strategic Prior- ity Research Program of Chinese Academy of Sciences (No.XDB17000000), and the Fundamental Research Funds for the Central Universities. We thank Chen-biao Xu at Dalian Institute of Chemical Physics, Chinese Academy of Sciences and Wen-shao Yang at Hangzhou Institute of Advanced Studies, Zhejiang Normal Uni- versity for their help during experiments.
文摘Photocatalysis of CH3OH on the ZnO(0001) surface has been investigated by using temperature-programmed desorption (TPD) method with a 266 nm laser light. TPD results show that part of the CH3OH adsorbed on ZnO(0001) surface are in molecular form, while others are dissociated. The thermal reaction products of H2, CH3·, H2O, CO, CH2O, CO2 and CH3OH have been detected. Experiments with the UV laser light indicate that the irradiation can promote the dissociation of CH3OH/CH3O· to form CH2O, which can be fu- ture converted to HCOO- during heating or illumination. The reaction between CH3OHZn and OHad can form the H2O molecule at the Zn site. Both temperature and illumination promote the desorption of CH3· from CH3O·. The research provides a new insight into the photocatalytic reaction mechanism of CH3OH on ZnO(0001).
基金financially supported by the Science Foundation of China University of Petroleum,Beijing (No. 2462019BJRC001)
文摘Developing the multifunctional nanocarriers for long-term drug release and luminescence traceability is a challenging assignment.In this task,we designed a novel nanoplatform for long-term and luminescence trackable chemotherapy,which is prepared via a hollow ZIF-8(where ZIF is zeolitic imidazolate frameworks)coated by the Eu^(3+)-doped mesoporous silica(ZIF-8@mesoporous silica).The hollow ZIF-8 is used as a drug library for loading the anticancer drug,and the pH-sensitive properties of ZIF-8 can targeted-release drugs in the tumor and cut down the poisonousness of drugs to normal cells.The shell layer of mesoporous silica can achieve the long-term drug release,which solves the problem of short drug circulation time in the body,reduces the drug administration frequency,and improves the therapeutic effect.Notably,the ZIF-8@mesoporous+doxorubicin(DOX)is injected only once during the 14-day chemotherapy.In addition,Eu^(3+)doped in mesoporous silica ensures luminescence tracking and detection of drug pathways in living cells.Hence,this nanoplatform provides a whole new strategy for the longterm treatment of tumors.
基金financially supported by the National High Technology Research and Development Program of China(No.2012AA03A503)the National Natural Science Foundation of China(Nos.51174057 and 51274062)Research Fund for the Doctoral Program of Higher Education of China(No.20130042110040)
文摘Thermo-mechanical process and continuous cooling process were carried out on 20CrNi2MoV steel. Three cooling rates were implemented to optimize the mechanical properties. The microstructure evolution, precipitation behavior, and strengthening mechanisms were systematically investigated, and the fracture mechanisms were analyzed via combination of impact fracture morphologies and deflection-load curves. The experimental results indicate that the transformed microstructure of experimental steel is all complex consisting of granular bainitic ferrite and bainitic ferrite with dispersed martensite/austenite （M/A） constituents in the matrix at cooling rates of 13, 21, and 29 ℃/s. When the cooling rate increases, the grain of the steel is obviously refined. The sizes of the bainitic ferrite are 5.8, 4.7, and 3.1 μm under cooling rates of 13, 21, and 29 ℃/s, respectively. The refinement of the bainitic ferrite plays a dominant role in strength increasing and also contributes to high crack propagation energy. However, the morphologies of M/A constituents obtained under different cooling rates contribute to different crack initiation energies and then affect the impact property.
基金Project supported by the Hi-Tech Research and Development Program(863)of China(No.2006AA09Z427)the National Natural Science Foundation of China(Nos.30800859 and 30871948)
文摘Ethanol extracts of brown seaweeds from Pakistan and China were isolated and compared for their antiallergenic activities. They included Sargassum tennerimum (ST) and Sargassum cervicorne (SC) from Pakistan, and Sargassum gramini- folium turn (SG), Sargassum thunbergii (STH), and Laminaria japonica (LJ) from China. The ethanol extracts of these brown seaweeds were optimized at 85% (v/v) ethanol for the maximum yield of phlorotannin, an inhibitor against hyaluronidase. Total phlorotannins contained in the crude extracts were measured as 1.71% (SG), 0.74% (STH), 0.97% (LJ), 3.30% (SC), and 5.06% (ST). The 50% inhibitory concentrations (IC50) of Pakistani SC and ST were 109.5 and 21 μg/ml, respectively, lower than those of Chinese SG, STH, and LJ (134, 269, and 148 μg/ml, respectively). An antiallergic drug, disodium cromoglycate (DSCG), had an IC50=39 μg/ml, and a natural inhibitor of hyaluronidase, catechin, had an IC50=20 μg/ml. The IC50 of ST extract was found similar to that of catechin (21 vs 20 μg/ml) and lower than that of DSCG (21 vs 39 μg/ml). This suggests that ST is a potent inhibitor of hyaluronidase, indicating a promising future development of natural antiallergic medicines or functional foods.
基金Item Sponsored by National Natural Science Foundation of China(51174057,51274062)National High Technology Researchand Development Program of China(2012AA03A503)
文摘In order to optimize the production process, improve the production efficiency and accelerate the development and application of the domestic dual-phase steel, the effects of heat treatment process parameters on microstructure and mechanical properties of DP440 cold rolled strip were studied by the CAS-300 simulated continuous annealing equipment. When the heating rate increased from 5 to 100 ℃/s, both the tensile strength and yield strength increased because of the decreased grain size. When the intercritical annealing temperature increased from 780 to 850 ℃, the martensite content decreased so that the tensile strength decreased first, then increased, and the yield strength increased. When the rapid cooling rate increased from 25 to 100 ℃/s, because the martensite content increased, the tensile strength increased, while the yield strength decreased. When the overaging temperature increased from 260 to 400 ℃, the tensile strength decreased, while the yield strength increased. When the overaging time increased from 240 to 480 s, the tensile strength decreased a little, while the yield strength increased a little.
