1. A hexagonal type barium titanate powder comprising barium titanate as a main component shown by a generic formula of (Ba1-\u03b1M\u03b1)A(Ti1-\u03b2Mn\u03b2)BO3 and having a hexagonal structure wherein:
an effective ionic radius of 12-coordinated \u201cM\u201d is \u221220% or more to +20% or less with respect to an effective ionic radius of 12-coordinated Ba2+, and
said A, B, \u03b1, and \u03b2 satisfy:
1.000<(AB)\u22661.040,
0\u2266\u03b1\u22660.0025, and
0.03\u2266\u03b2\u22660.2.
2. The hexagonal type barium titanate powder as set forth in claim 1, wherein:
a ratio of said \u03b1 and said \u03b2 satisfies (\u03b1\u03b2)\u22660.40.
3. A method of producing the hexagonal type barium titanate powder as set forth in claim 2 comprising steps of:
preparing at least a raw material of barium titanate and a raw material of Mn, and
heat-treating said raw material of barium titanate and said raw material of said Mn.
4. A method of producing the hexagonal type barium titanate powder as set forth in claim 1 comprising steps of:
preparing at least a raw material of barium titanate and a raw material of Mn, and
heat-treating said raw material of barium titanate and said raw material of said Mn.
5. A dielectric ceramic composition comprising a hexagonal type barium titanate as a main component shown by a generic formula of (Ba1-\u03b1M\u03b1)A(Ti1-\u03b2Mn\u03b2)BO3 and having a hexagonal structure wherein:
an effective ionic radius of 12-coordinated \u201cM\u201d is \u221220% or more to +20% or less with respect to an effective ionic radius of 12-coordinated Ba2+, and said A, B, \u03b1, and \u03b2 satisfy:
1.000<(AB)\u22661.040,
0\u2266a\u22660.0025, and
0.03\u2266\u03b2\u22660.2, and
as subcomponents, with respect to 100 moles of the main component, 2 to 5 moles of at least one of alkaline earth oxide selected from the group consisting of MgO, CaO, and BaO in terms of respective oxides, and a total content of said alkaline earth oxides is 15 moles or less; 0.5 to 2 moles of Mn3O4 andor Cr2O3, and CuO and Al2O3 in terms of respective metal elements; 1 to 5 moles of at least one of oxides of rare earth element selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, and Yb in terms of a total of rare earth element; and 0.1 to 1 mole of a glass component including SiO2 in terms of SiO2.
6. An electronic component comprising a dielectric layer composed of the dielectric ceramic composition as set forth in claim 5 and an internal electrode layer.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A support post for a rockfall barrier comprising:
a base;
a first arm pivotally coupled to the base at a first hinge;
a first hinge brake for providing friction at the first hinge to provide controlled resistance against pivotal rotation of the first arm relative to the base;
a second aim pivotally coupled to the first arm at a second hinge; and
a second hinge brake for providing friction at the second hinge to provide controlled resistance against relative pivotal rotation between the first arm and the second arm.
2. The support post of claim 1 wherein the first arm is configurable at a 0\xb0-90\xb0 angle to the normal of a sloped surface and the second aim is configurable at a 0\xb0-90\xb0 angle to the normal to the sloped surface, wherein the first aim and the second arm foam a concavity facing an upslope direction.
3. The support post of claim 1 wherein the first arm is configurable at a 0\xb0-45\xb0 angle to the normal of a sloped surface and the second aim is configurable at a 0\xb0-30\xb0 angle to the normal to the sloped surface.
4. The support post of claim 3 wherein the second arm is longer than the first arm.
5. The support post of claim 4 wherein the ratio between the lengths of the second arm and the first arm ranges from about 2:1 to 4:1.
6. The support post of claim 5 wherein the first hinge brake comprises a first pair of friction plates and the second hinge brake comprises a second pair of friction plates.
7. The support post of claim 6 wherein the first and second pairs of friction plates comprise stops to prevent the support post from over-rotating in the upslope direction.
8. A rock fall barrier comprising:
a plurality of support posts, each support post comprising:
a base fixed to a sloped surface;
a first arm pivotally coupled to the base at a first hinge;
a first hinge brake for providing friction at the first hinge to provide controlled resistance against pivotal rotation of the first arm relative to the base;
a second arm pivotally coupled to the first arm at a second hinge; and
a second hinge brake for providing friction at the second hinge to provide controlled resistance against relative pivotal rotation between the first arm and the second arm; and
a deformable net spanning the plurality of support posts.
9. The rockfall barrier of claim 8 comprising at least one guy wire attached at one end to a distal end of one of the plurality of support posts and anchored at the other end to the sloped surfaced.
10. The rockfall barrier of claim 9 wherein the at least one guy wire comprises a cable brake.