Abstract: A tractor includes a working motor, a work machine including a roller configured to rotate by an output from the working motor, a support mechanism configured to support the work machine such that a working posture and a retracting posture are achievable, and a control device. The control device executes: an adherence amount acquisition process of acquiring an estimated adherence amount as an estimated value for the amount of mud attached to the roller; and a mud removal process of, when the estimated adherence amount is equal to or more than a determination adherence amount, removing the mud from the roller by driving the working motor in a state where the work machine takes the retracting posture.

Abstract: The present invention aims to obtain a resin composition with low thermal expansion property by suppressing functional deterioration in negative thermal expansion property when a negative thermal expansion material is added to a thermoplastic resin and heat-processed. The present invention provides a resin composition including metal oxide particles and a thermoplastic resin, both having a negative thermal expansion property. The negative thermal expansion of the particles is attributed to a crystal phase transition, which is driven by electron transfer between the constituent metals, and a covalent protective layer that inhibits the electron transfer is formed between the particles and the thermoplastic resin.

Abstract: A composite material of one aspect includes a resin matrix phase, and a ruthenium oxide having Ca2RuO4 structure and included in the resin matrix phase. The ruthenium oxide may be represented by a general formula (1): Ca2?xRxRu1?y1MyO4+z, in which R may represent at least one element selected from among alkaline earth metals and rare earth elements, M may represent at least one element selected from among Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, and Ga, and the values x, y, and z may satisfy 0?x<0.2, 0?y<0.3, and ?1<z<?0.02.

Abstract: Provided are a thermal expansion suppressing member having negative thermal expansion properties and a metal-based anti-thermally-expansive member having small thermal expansion. More specifically, provided are a thermal expansion suppressing member, including at least an oxide represented by the following general formula (1), and an anti-thermally-expansive member, including a metal having a positive linear expansion coefficient at 20° C., and a solid body including at least an oxide represented by the following general formula (1), the metal and solid being joined to each other: (Bi1-xMx)NiO3 (1) where M represents at least one metal selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y, and In; and x represents a numerical value of 0.02?x?0.15.

Abstract: Provided is a piezoelectric material excellent in piezoelectricity. The piezoelectric material includes a perovskite-type complex oxide represented by the following General Formula (1). A(ZnxTi(1-x))yM(1-y)O3??(1) wherein A represents at least one kind of element containing at least a Bi element and selected from a trivalent metal element; M represents at least one kind of element of Fe, Al, Sc, Mn, Y, Ga, and Yb; x represents a numerical value satisfying 0.4?x?0.6; and y represents a numerical value satisfying 0.1?y?0.9.

Abstract: Provided are a piezoelectric thin film having good piezoelectricity in which a rhombohedral structure and a tetragonal structure are mixed, and a piezoelectric element using the piezoelectric thin film. The piezoelectric thin film includes a perovskite type metal oxide, in which the perovskite type metal oxide is a mixed crystal system of at least a rhombohedral structure and a tetragonal structure, and a ratio between an a-axis lattice parameter and a c-axis lattice parameter of the tetragonal structure satisfies 1.15?c/a?1.30. The piezoelectric element includes on a substrate: the above-mentioned piezoelectric thin film; and a pair of electrodes provided in contact with the piezoelectric thin film.

Abstract: Provided are a bismuth-based piezoelectric material whose insulation property is improved while its performance as a piezoelectric body is not impaired and a piezoelectric device using the piezoelectric material. The piezoelectric material includes a perovskite-type metal oxide represented by the following general formula (1): Bix(Fe1-yCoy)O3??(1) where 0.95?x?1.25 and 0?y?0.30, and a root mean square roughness Rq (nm) of a surface of the piezoelectric material satisfies a relationship of 0<Rq?25y+2 (0?y?0.30).

Abstract: Provided are resin-based and metal-based anti-thermally-expansive members each having small thermal expansion. More specifically, provided are an anti-thermally-expansive resin and an anti-thermally-expansive metal, each including a resin or a metal having a positive linear expansion coefficient at 20° C. and a solid particle dispersed in the resin or metal, in which the solid particle includes at least an oxide represented by the following general formula (1): (Bi1-xMx)NiO3 (1), where M represents at least one metal selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y, and In; and x represents a numerical value of 0.02?x?0.15.

Abstract: Provided are a thermal expansion suppressing member having negative thermal expansion properties and a metal-based anti-thermally-expansive member having small thermal expansion. More specifically, provided are a thermal expansion suppressing member, including at least an oxide represented by the following general formula (1), and an anti-thermally-expansive member, including a metal having a positive linear expansion coefficient at 20° C., and a solid body including at least an oxide represented by the following general formula (1), the metal and solid being joined to each other: (Bi1-xMx)NiO3 (1) where M represents at least one metal selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y, and In; and x represents a numerical value of 0.02?x?0.15.

Abstract: Provided are a thermal expansion suppressing member having negative thermal expansion properties and a metal-based anti-thermally-expansive member having small thermal expansion. More specifically, provided are a thermal expansion suppressing member, including at least an oxide represented by the following general formula (1), and an anti-thermally-expansive member, including a metal having a positive linear expansion coefficient at 20° C., and a solid body including at least an oxide represented by the following general formula (1), the metal and solid being joined to each other: (Bi1-xMx)NiO3 (1) where M represents at least one metal selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y, and In; and x represents a numerical value of 0.02?x?0.15.

Abstract: Provided are resin-based and metal-based anti-thermally-expansive members each having small thermal expansion. More specifically, provided are an anti-thermally-expansive resin and an anti-thermally-expansive metal, each including a resin or a metal having a positive linear expansion coefficient at 20° C. and a solid particle dispersed in the resin or metal, in which the solid particle includes at least an oxide represented by the following general formula (1): (Bi1-xMx)NiO3 (1), where M represents at least one metal selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y, and In; and x represents a numerical value of 0.02?x?0.15.

Abstract: Provided are resin-based and metal-based anti-thermally-expansive members each having small thermal expansion. More specifically, provided are an anti-thermally-expansive resin and an anti-thermally-expansive metal, each including a resin or a metal having a positive linear expansion coefficient at 20° C. and a solid particle dispersed in the resin or metal, in which the solid particle includes at least an oxide represented by the following general formula (1): (Bi1-xMx)NiO3??(1), where M represents at least one metal selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y, and In; and x represents a numerical value of 0.02?x?0.15.

Abstract: Provided is a piezoelectric material excellent in piezoelectricity. The piezoelectric material includes a perovskite-type complex oxide represented by the following General Formula (1). A(ZnxTi(1-x))yM(1-y)O3??(1) wherein A represents at least one kind of element containing at least a Bi element and selected from a trivalent metal element; M represents at least one kind of element of Fe, Al, Sc, Mn, Y, Ga, and Yb; x represents a numerical value satisfying 0.4?x?0.6; and y represents a numerical value satisfying 0.1?y?0.9.

Abstract: Provided is a piezoelectric material excellent in piezoelectricity. The piezoelectric material includes a perovskite-type complex oxide represented by the following General Formula (1). A(ZnxTi(1-x))yM(1-y)O3??(1) wherein A represents at least one kind of element containing at least a Bi element and selected from a trivalent metal element; M represents at least one kind of element of Fe, Al, Sc, Mn, Y, Ga, and Yb; x represents a numerical value satisfying 0.4?x?0.6; and y represents a numerical value satisfying 0.1?y?0.9.

Abstract: Provided are a bismuth-based piezoelectric material whose insulation property is improved while its performance as a piezoelectric body is not impaired, and a piezoelectric device using the piezoelectric material. The piezoelectric material includes a perovskite-type metal oxide represented by the following general formula (1): Bix(Fe1-yCoy)O3??(1) where 0.95?x?1.25 and 0?y?0.30, and a root mean square roughness Rq (nm) of a surface of the piezoelectric material satisfies a relationship of 0<Rq?25y+2 (0?y?0.30).

Abstract: Provided are a piezoelectric thin film having good piezoelectricity in which a rhombohedral structure and a tetragonal structure are mixed, and a piezoelectric element using the piezoelectric thin film. The piezoelectric thin film includes a perovskite type metal oxide, in which the perovskite type metal oxide is a mixed crystal system of at least a rhombohedral structure and a tetragonal structure, and a ratio between an a-axis lattice parameter and a c-axis lattice parameter of the tetragonal structure satisfies 1.15?c/a?1.30. The piezoelectric element includes on a substrate: the above-mentioned piezoelectric thin film; and a pair of electrodes provided in contact with the piezoelectric thin film.

Abstract: Provided are resin-based and metal-based anti-thermally-expansive members each having small thermal expansion. More specifically, provided are an anti-thermally-expansive resin and an anti-thermally-expansive metal, each including a resin or a metal having a positive linear expansion coefficient at 20° C. and a solid particle dispersed in the resin or metal, in which the solid particle includes at least an oxide represented by the following general formula (1): (Bi1-xMx)NiO3 (1), where M represents at least one metal selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y, and In; and x represents a numerical value of 0.02?x?0.15.

Abstract: Provided are a thermal expansion suppressing member having negative thermal expansion properties and a metal-based anti-thermally-expansive member having small thermal expansion. More specifically, provided are a thermal expansion suppressing member, including at least an oxide represented by the following general formula (1), and an anti-thermally-expansive member, including a metal having a positive linear expansion coefficient at 20° C., and a solid body including at least an oxide represented by the following general formula (1), the metal and solid being joined to each other: (Bi1-xMx)NiO3 (1) where M represents at least one metal selected from the group consisting of La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y, and In; and x represents a numerical value of 0.02?x?0.15.

Abstract: Provided is a piezoelectric material including a lead-free perovskite-type composite oxide which is excellent in piezoelectric characteristics and temperature characteristics and is represented by the general formula (1): xABO3-yA?BO3-zA?B?O3 in which A is a Bi element; A? is a rare earth element including La; B is at least one element selected from Ti, Zn, Sn and Zr; A? is at least one element selected from Ba, Sr and Ca; B? is at least one element selected from divalent, trivalent, pentavalent, tetravalent, and hexavalent elements; and x is a value of 0.10 or more and 0.95 or less, y is a value of 0 or more and 0.5 or less, and z is a value of 0 or more and 0.7 or less, provided that x+y+z=1.

Abstract: An oxynitride piezoelectric material, which exhibits ferroelectricity and has good piezoelectric properties, and a method of producing the oxynitride piezoelectric material. The oxynitride piezoelectric material includes a tetragonal perovskite-type oxynitride represented by the following general formula (1): A1?xBix+?1B1?yB?y+?2O3?zNz??(1), where A represents a divalent element, B and B? each represent a tetravalent element, x represents a numerical value of 0.35 or more to 0.6 or less, y represents a numerical value of 0.35 or more to 0.6 or less, z represents a numerical value of 0.35 or more to 0.6 or less, and ?1 and ?2 each represent a numerical value of ?0.2 or more to 0.2 or less, in which the A includes at least one kind selected from Ba, Sr, and Ca and the B and the B? each include at least one kind selected from Ti, Zr, Hf, Si, Ge, and Sn.