Epitaxial ferroelectric one direction over the thin fihns on single-crystal substrates generally show a preferred domain orientation in other in demonstration of a poor polarization retention. This behavior will affec...Epitaxial ferroelectric one direction over the thin fihns on single-crystal substrates generally show a preferred domain orientation in other in demonstration of a poor polarization retention. This behavior will affect their application in nonvolatile ferroelectric random access memories where bipolar polarization states are used to store the logic 0 and 1 data. Here the retention characteristics of BiFe03 thin films with Srftu03 bottom electrodes on both GdSc03 (110) and SrTiO3 (100) substrates are studied and compared, and the results of piezoresponse force microscopy provide a long time retention property of the films on two substrates. It is found that bismuth ferrite thin films grown on GdScO3 substrates show no preferred domain variants in comparison with the preferred downward polarization orientation toward bottom electrodes on SrTi03 substrates. Tile retention test from a positive-up domain to a negative-down domain using a signal generator and an oscilloscope coincidentally shows bistable polarization states on the GdSeOa substrate over a measuring time of 500s, unlike the preferred domain orientation on SrTi03, where more than 65~o of upward domains disappear after 1 s. In addition, different sizes of domains have been written and read by using the scanning tip of piezoresponse force microscopy, where the polarization can stabilize over one month. This study paves one route to improve the polarization retention property through the optimization of the lattice-mismatched stresses between films and substrates.展开更多
Protein arginine methyltransferase 7(PRMT7)is closely related to the formation of lung cancer,breast cancer and other malignant tumors,and it may be a potential target gene for malignant tumor therapy.Dishevelleds(DVL...Protein arginine methyltransferase 7(PRMT7)is closely related to the formation of lung cancer,breast cancer and other malignant tumors,and it may be a potential target gene for malignant tumor therapy.Dishevelleds(DVLs)are key factors involved in cell proliferation,invasion and metastasis.Among the dishevelleds,the dishevelled segment polarity protein 3(DVL3)is a key protein in the Wnt signaling pathway,and its abnormal expression plays an important role in the occurrence and development of malignant tumors.This paper reviewed the advances in research of PRMT7 and DVL3 in gastric cancer.展开更多
The first-principles calculations are employed to investigate the electrical properties of polar MgO/BaTiO3(110)interfaces. Both n-type and p-type polar interfaces show a two-dimensional metallic behavior. For the n...The first-principles calculations are employed to investigate the electrical properties of polar MgO/BaTiO3(110)interfaces. Both n-type and p-type polar interfaces show a two-dimensional metallic behavior. For the n-type polar interface,the interface Ti3d electrons are the origin of the metallic and magnetic properties. Varying the thickness of Ba TiO3 may induce an insulator–metal transition, and the critical thickness is 4 unit cells. For the p-type polar interface, holes preferentially occupy the interface O 2p y state, resulting in a conducting interface. The unbalance of the spin splitting of the O 2p states in the interface Mg O layer leads to a magnetic moment of about 0.25μB per O atom at the interface.These results further demonstrate that other polar interfaces, besides LaAlO3/SrTiO3, can show a two-dimensional metallic behavior. It is helpful to fully understand the role of polar discontinuity on the properties of the interface, which widens the field of polar-nonpolar interfaces.展开更多
Polycrystalline Bi_4Ti_3O_(12) thin films with various fractions of a-axis, c-axis and random orientations have been grown on Pt(111)/Ti/Si O_2/Si substrates by laser-ablation under different kinetic growth condit...Polycrystalline Bi_4Ti_3O_(12) thin films with various fractions of a-axis, c-axis and random orientations have been grown on Pt(111)/Ti/Si O_2/Si substrates by laser-ablation under different kinetic growth conditions. The relationship between the structure and ferroelectric property of the films was investigated, so as to explore the possibility of enhancing ferroelectric polarization by controlling the preferred orientation. The structural characterization indicated that the large growth rate and high oxygen background pressure were both favorable for the growth of non-c-axis oriented grains in the Bi_4Ti_3O_(12) thin films. The films with high fractions of a-axis and random orientations, i e, f(a-sxis) = 28.3% and f(random) = 69.6%, could be obtained at the deposition temperature of 973 K, oxygen partial pressure of 15 Pa and laser fluence of 4.6 J/cm^2, respectively. It was also noted that the variation of ferroelectric polarization was in accordance with the evolution non-c-axis orientation. A large value of remanent polarization(2 Pr = 35.5 μC/cm^2) was obtained for the Bi_4Ti_3O_(12) thin films with significant non-c-axis orientation, even higher than that of rare-earth-doped Bi_4Ti_3O_(12) films.展开更多
In this paper,we present the performance of a recently developed in-situ spin-exchange optically pumped^(3)He-neutron spin filter system at the China Spallation Neutron Source(CSNS).The system achieved a^(3)He polariz...In this paper,we present the performance of a recently developed in-situ spin-exchange optically pumped^(3)He-neutron spin filter system at the China Spallation Neutron Source(CSNS).The system achieved a^(3)He polarization of over 74%at the beamline BL-20.Analysis of neutron transmission experiment results reveals a neutron polarization of>90%and an average transmission of 27%for 2.2Åneutrons,which were maintained for a duration of 120 h of beam time.To the best of our knowledge,this is the first in-situ hyperpolarized^(3)He system incorporated on a neutron beamline in China.This technology is expected to provide stable,wide-angle,and highly polarized neutrons at the CSNS for materials research and fundamental neutron physics.展开更多
We report the density measurement through e-3He elastic scattering with a 1.23 GeV electron beam in Jefferson Lab experiment E06-010. The extracted 3He density is (9.26±0.06) amagats and the N2/3He ratio is (1...We report the density measurement through e-3He elastic scattering with a 1.23 GeV electron beam in Jefferson Lab experiment E06-010. The extracted 3He density is (9.26±0.06) amagats and the N2/3He ratio is (1.49±0.08)%. In addition, these results are consistent with the deduced target densities based on pressure broadening measurement.展开更多
基金Supported by the National Basic Research Program of China under Grant No 2014CB921004the National Natural Science Foundation of China under Grant No 61225020
文摘Epitaxial ferroelectric one direction over the thin fihns on single-crystal substrates generally show a preferred domain orientation in other in demonstration of a poor polarization retention. This behavior will affect their application in nonvolatile ferroelectric random access memories where bipolar polarization states are used to store the logic 0 and 1 data. Here the retention characteristics of BiFe03 thin films with Srftu03 bottom electrodes on both GdSc03 (110) and SrTiO3 (100) substrates are studied and compared, and the results of piezoresponse force microscopy provide a long time retention property of the films on two substrates. It is found that bismuth ferrite thin films grown on GdScO3 substrates show no preferred domain variants in comparison with the preferred downward polarization orientation toward bottom electrodes on SrTi03 substrates. Tile retention test from a positive-up domain to a negative-down domain using a signal generator and an oscilloscope coincidentally shows bistable polarization states on the GdSeOa substrate over a measuring time of 500s, unlike the preferred domain orientation on SrTi03, where more than 65~o of upward domains disappear after 1 s. In addition, different sizes of domains have been written and read by using the scanning tip of piezoresponse force microscopy, where the polarization can stabilize over one month. This study paves one route to improve the polarization retention property through the optimization of the lattice-mismatched stresses between films and substrates.
基金Supported by Chengde Medical University-National Natural Science Foundation of China Project Cultivation Fund (202114)Chengde Medical UniversitySchool-level Key Project Fund (201711)+1 种基金Key Discipline Construction Project of Hebei Province [Ji Jiao Gao (2013) No. 4:Pathology and Pathophysiology]Master Candidate Innovation Ability Training Funding Project of Hebei Province (CXZZSS2022141)
文摘Protein arginine methyltransferase 7(PRMT7)is closely related to the formation of lung cancer,breast cancer and other malignant tumors,and it may be a potential target gene for malignant tumor therapy.Dishevelleds(DVLs)are key factors involved in cell proliferation,invasion and metastasis.Among the dishevelleds,the dishevelled segment polarity protein 3(DVL3)is a key protein in the Wnt signaling pathway,and its abnormal expression plays an important role in the occurrence and development of malignant tumors.This paper reviewed the advances in research of PRMT7 and DVL3 in gastric cancer.
基金supported by the National Basic Research Program of China(Grant No.2013CB632506)the National Natural Science Foundation of China(Grant Nos.11374186,51231007,51202132,and 51102153)the Independent Innovation Foundation of Shandong University,China(Grant No.2012TS027)
文摘The first-principles calculations are employed to investigate the electrical properties of polar MgO/BaTiO3(110)interfaces. Both n-type and p-type polar interfaces show a two-dimensional metallic behavior. For the n-type polar interface,the interface Ti3d electrons are the origin of the metallic and magnetic properties. Varying the thickness of Ba TiO3 may induce an insulator–metal transition, and the critical thickness is 4 unit cells. For the p-type polar interface, holes preferentially occupy the interface O 2p y state, resulting in a conducting interface. The unbalance of the spin splitting of the O 2p states in the interface Mg O layer leads to a magnetic moment of about 0.25μB per O atom at the interface.These results further demonstrate that other polar interfaces, besides LaAlO3/SrTiO3, can show a two-dimensional metallic behavior. It is helpful to fully understand the role of polar discontinuity on the properties of the interface, which widens the field of polar-nonpolar interfaces.
基金Funded by the International Science and Technology Cooperation Project of Hubei Province(2016AHB008)the Natural Science Foundation of Hubei Province(2015CFB724,2016CFA006)+1 种基金the National Natural Science Foundation of China(51272195,51521001)the National Key Research and Development Program of China(2017YFB0310400)
文摘Polycrystalline Bi_4Ti_3O_(12) thin films with various fractions of a-axis, c-axis and random orientations have been grown on Pt(111)/Ti/Si O_2/Si substrates by laser-ablation under different kinetic growth conditions. The relationship between the structure and ferroelectric property of the films was investigated, so as to explore the possibility of enhancing ferroelectric polarization by controlling the preferred orientation. The structural characterization indicated that the large growth rate and high oxygen background pressure were both favorable for the growth of non-c-axis oriented grains in the Bi_4Ti_3O_(12) thin films. The films with high fractions of a-axis and random orientations, i e, f(a-sxis) = 28.3% and f(random) = 69.6%, could be obtained at the deposition temperature of 973 K, oxygen partial pressure of 15 Pa and laser fluence of 4.6 J/cm^2, respectively. It was also noted that the variation of ferroelectric polarization was in accordance with the evolution non-c-axis orientation. A large value of remanent polarization(2 Pr = 35.5 μC/cm^2) was obtained for the Bi_4Ti_3O_(12) thin films with significant non-c-axis orientation, even higher than that of rare-earth-doped Bi_4Ti_3O_(12) films.
基金supported by the National Key Research and Development Program of China(Grant No.2020YFA0406000)National Natural Science Foundation of China(Grant No.11875265)+2 种基金Scientific Instrument Developing Project of the Chinese Academy of Sciences(Grant No.ZDKYYQ20190004)Guangdong Basic and Applied Basic Research Foundation(Grant No.2019B1515120079)Dongguan Introduction Program of Leading Innovative and Entrepreneurial Talents(Grant No.20191122)。
文摘In this paper,we present the performance of a recently developed in-situ spin-exchange optically pumped^(3)He-neutron spin filter system at the China Spallation Neutron Source(CSNS).The system achieved a^(3)He polarization of over 74%at the beamline BL-20.Analysis of neutron transmission experiment results reveals a neutron polarization of>90%and an average transmission of 27%for 2.2Åneutrons,which were maintained for a duration of 120 h of beam time.To the best of our knowledge,this is the first in-situ hyperpolarized^(3)He system incorporated on a neutron beamline in China.This technology is expected to provide stable,wide-angle,and highly polarized neutrons at the CSNS for materials research and fundamental neutron physics.
基金Supported by National Natural Science Foundation of China (11075068, 10775062, 91026021, 11135002)
文摘We report the density measurement through e-3He elastic scattering with a 1.23 GeV electron beam in Jefferson Lab experiment E06-010. The extracted 3He density is (9.26±0.06) amagats and the N2/3He ratio is (1.49±0.08)%. In addition, these results are consistent with the deduced target densities based on pressure broadening measurement.