The effect of magnetic field and ionizing radiation on the mechanical properties of polymer blends consisting of high density polyethylene （HDPE） and acrylonitrile-butadiene rubber （NBR） has been investigated. The...The effect of magnetic field and ionizing radiation on the mechanical properties of polymer blends consisting of high density polyethylene （HDPE） and acrylonitrile-butadiene rubber （NBR） has been investigated. The purpose of the work was to create HDPE/NBR blend composites of significantly different compositions （with an excess of HDPE, intermediate ones, and with an excess of NBR） and to investigate the role of composition on mechanical deformation properties under the influence of magnetic field. The investigation has importance from the engineering viewpoint, since thermoplastic composite materials have been used as structural elements in thermonuclear and engineering fields, like wires, insulation materials and others, which are frequently subjected to mechanical loadings under the effect of magnetic field greater than 1 T. One part of the blends has been irradiated with 5 MeV accelerated electrons up to absorbed dose D equal to 150 kGy. Unirradiated and the radiation modified blends have been exposed to a constant magnetic field with induction B equal to 1.0 T, 1.5 T and 1.7 T. It is found that the action of magnetic field decreases the elastic modulus of unirradiated materials. Decrement of elastic modulus is reduced with increase of the content of NBR in composites. It is also found that preliminary irradiation noticeably decreases the effect of magnetic field. Data of the influence of the magnetic field, radiation cross-linking, and the ratio of the components on the creep are also obtained.展开更多
A 3D mixed-valence Co（Ⅲ）-Co（Ⅱ） compound [Co9（bta）10（Hbta）2（H2O）10]n·[22（H2O）]n （1） （H2bta=N,N-bis（1H-tetrazole-5- yl）-amine） was hydrothermally synthesized by reaction of Co（NO3）2·6H2O ...A 3D mixed-valence Co（Ⅲ）-Co（Ⅱ） compound [Co9（bta）10（Hbta）2（H2O）10]n·[22（H2O）]n （1） （H2bta=N,N-bis（1H-tetrazole-5- yl）-amine） was hydrothermally synthesized by reaction of Co（NO3）2·6H2O with H2bta·H2O. Compound 1 consists of three kinds of distorted-octahedral [CoⅡ（N4O2）] paramagnetic nodes which are separated by [CoⅢ（bta）2（Hbta）]2-/[CoⅢ（bta）3]3- dia- magnetic linkers to generate a 3D porous metal-organic framework （MOF） with alternative …Co（Ⅲ）…Co（II）… array and channels incorporating water molecules. Under an applied magnetic field of 4000 Oe, compound 1 exhibits slow relaxation of magnetization at low temperatures, giving AE/kB=30.O0 K and ι0=2.0×10^-8 s.展开更多
We report the fabrication of a highly sensitive field-effect transistor （FET） biosensor using thermally-reduced graphene oxide （TRGO） sheets functionalized with gold nanoparticle （NP）-antibody conjugates. Probe ...We report the fabrication of a highly sensitive field-effect transistor （FET） biosensor using thermally-reduced graphene oxide （TRGO） sheets functionalized with gold nanoparticle （NP）-antibody conjugates. Probe antibody was labeled on the surface of TRGO sheets through Au NPs and electrical detection of protein binding （Immunoglobulin G/IgG and anti-lmmunoglobulin G/anti-lgG） was accomplished by FET and direct current （dc） measurements. The protein binding events induced significant changes in the resistance of the TRGO sheet, which is referred to as the sensor response. The dependence of the sensor response on the TRGO base resistance in the sensor and the antibody areal density on the TRGO sheet was systematically studied, from which a correlation of the sensor response with sensor parameters was found： the sensor response was more significant with larger TRGO base resistance and higher antibody areal density. The detection limit of the novel biosensor was around the 0.2 ng/rnL level, which is among the best of,＇eported carbon nanomaterial-based protein sensors and can be further optimized by tuning the sensor structure.展开更多
文摘The effect of magnetic field and ionizing radiation on the mechanical properties of polymer blends consisting of high density polyethylene （HDPE） and acrylonitrile-butadiene rubber （NBR） has been investigated. The purpose of the work was to create HDPE/NBR blend composites of significantly different compositions （with an excess of HDPE, intermediate ones, and with an excess of NBR） and to investigate the role of composition on mechanical deformation properties under the influence of magnetic field. The investigation has importance from the engineering viewpoint, since thermoplastic composite materials have been used as structural elements in thermonuclear and engineering fields, like wires, insulation materials and others, which are frequently subjected to mechanical loadings under the effect of magnetic field greater than 1 T. One part of the blends has been irradiated with 5 MeV accelerated electrons up to absorbed dose D equal to 150 kGy. Unirradiated and the radiation modified blends have been exposed to a constant magnetic field with induction B equal to 1.0 T, 1.5 T and 1.7 T. It is found that the action of magnetic field decreases the elastic modulus of unirradiated materials. Decrement of elastic modulus is reduced with increase of the content of NBR in composites. It is also found that preliminary irradiation noticeably decreases the effect of magnetic field. Data of the influence of the magnetic field, radiation cross-linking, and the ratio of the components on the creep are also obtained.
基金supported by the National Natural Science Foundation of China(21373162,21127004,21173168,21203149,21463020)the Natural Science Foundation of Shaanxi Province(11JS110,FF10091,SJ08B09)
文摘A 3D mixed-valence Co（Ⅲ）-Co（Ⅱ） compound [Co9（bta）10（Hbta）2（H2O）10]n·[22（H2O）]n （1） （H2bta=N,N-bis（1H-tetrazole-5- yl）-amine） was hydrothermally synthesized by reaction of Co（NO3）2·6H2O with H2bta·H2O. Compound 1 consists of three kinds of distorted-octahedral [CoⅡ（N4O2）] paramagnetic nodes which are separated by [CoⅢ（bta）2（Hbta）]2-/[CoⅢ（bta）3]3- dia- magnetic linkers to generate a 3D porous metal-organic framework （MOF） with alternative …Co（Ⅲ）…Co（II）… array and channels incorporating water molecules. Under an applied magnetic field of 4000 Oe, compound 1 exhibits slow relaxation of magnetization at low temperatures, giving AE/kB=30.O0 K and ι0=2.0×10^-8 s.
基金Financial support for this work was provided by the USA National Science Foundation （NSF） （Nos. CMMI- 0900509, CBET-0803142, and ECCS-0708998）. Graphene oxide samples were supplied by Prof. Rodney S. Ruoff. The authors thank Dr. Heather A. Owen for technical support with SEM, and Dr. Leonidas E. Ocola for assistance in the electrode fabrication. The e-beam lithography was performed at the Center for Nanoscale Materials of Argonne National Laboratory, which is supported by the USA Department of Energy （No. DE- AC02-06CH11357）. The SEM imaging was conducted at the Electron Microscope Laboratory of University of Wisconsin-Milwaukee.
文摘We report the fabrication of a highly sensitive field-effect transistor （FET） biosensor using thermally-reduced graphene oxide （TRGO） sheets functionalized with gold nanoparticle （NP）-antibody conjugates. Probe antibody was labeled on the surface of TRGO sheets through Au NPs and electrical detection of protein binding （Immunoglobulin G/IgG and anti-lmmunoglobulin G/anti-lgG） was accomplished by FET and direct current （dc） measurements. The protein binding events induced significant changes in the resistance of the TRGO sheet, which is referred to as the sensor response. The dependence of the sensor response on the TRGO base resistance in the sensor and the antibody areal density on the TRGO sheet was systematically studied, from which a correlation of the sensor response with sensor parameters was found： the sensor response was more significant with larger TRGO base resistance and higher antibody areal density. The detection limit of the novel biosensor was around the 0.2 ng/rnL level, which is among the best of,＇eported carbon nanomaterial-based protein sensors and can be further optimized by tuning the sensor structure.
