Disclosed herein are embodiments of low temperature co-fireable barium tungstate materials which can be used in combination with high dielectric materials, such as nickel zinc ferrite, to form composite structures, in particular for isolators and circulators for radiofrequency components. Embodiments of the material can include flux, such as bismuth vanadate, to reduce co-firing temperatures.

Shaped ceramic abrasive particles include a first surface having a perimeter having a perimeter comprising at least first and second edges. A first region of the perimeter includes the second edge and extends inwardly and terminates at two corners defining first and second acute interior angles. The perimeter has at most four corners that define acute interior angles. A second surface is disposed opposite, and not contacting, the first surface. A peripheral surface is disposed between and connects the first and second surfaces. The peripheral surface has a first predetermined shape. Methods of making the shaped ceramic abrasive particles, and abrasive articles including them are also disclosed.

An oxide ion conductor has a X.sub.3Z.sub.2(TO.sub.4).sub.3 structure, where X is a divalent metal element, Z is a trivalent metal element, and T is a tetravalent metal element, and has a composition expressed by (X.sub.1-xA.sub.x).sub.3(Z.sub.1-yB.sub.y).sub.2(T.sub.1-zC.sub.z).sub.3O.sub.12+δ where the element X is Ca, Fe, Gd, Ba, Sr, Mn, and/or Mg, the element Z is Al, Cr, Fe, Mn, V, Ga, Co, Ni, Ru, Rh, and/or Ir, the element T is Si and/or Ge, an element A is La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and/or Sr, an element B is Zn, Mn, Co, Ru, and/or Rh, and an element C is Si, Al, Ga, and/or Sn, 0≤x≤0.2, 0≤y≤0.2, and 0≤z≤0.2 are satisfied, and δ is a value securing electrical neutrality.

In an aspect, a ferrite composition comprises a Ru—Co.sub.2Z ferrite having the formula: (Ba.sub.3-xM.sub.x)Co.sub.2(M′Ru).sub.yFe.sub.24-2y-zO.sub.41, wherein M is at least one of Sr, Pb, or Ca; M′ is at least one of Co, Zn, Mg, or Cu; x is 1 to 3; y is greater than 0 to 2; and z is −4 to 4. In another aspect, an article comprises the ferrite composition. In yet another aspect, method of making the ferrite composition comprises mixing ferrite precursor compounds comprising Fe, Ba, Co, and Ru; and sintering the ferrite precursor compounds in an oxygen atmosphere to form the Ru—Co.sub.2Z ferrite.

A ferrite sintered magnet including ferrite grains having a hexagonal crystal structure. The ferrite grains satisfy 0.56≤W≤0.68 where W is an average value of circularities of the ferrite grains in a cross section parallel to an axis of easy magnetization.

Disclosed are an anti-corrosion and anti-coking ceramic coating with easy state identification for a coal-fired boiler and a preparation method thereof. The ceramic coating is formed by compounding a bottom coating layer and a surface coating layer, wherein the bottom coating layer is prepared from raw materials comprising sodium silicate, lanthanum oxide, niobium pentoxide, aluminum oxide, bismuth oxide, boron oxide, zinc oxide, silicon oxide, titanium dioxide, nano whisker, titanium nitride, and graphite fluoride, and the surface coating layer is prepared from raw materials comprising sodium silicate, lanthanum oxide, niobium pentoxide, chromium oxide, aluminum oxide, bismuth oxide, boron oxide, zinc oxide, silicon oxide, graphite fluoride, titanium nitride, silicon carbide, nano whisker, and cobalt green. An operating state of the ceramic coating is rapidly identified by a color difference between the bottom coating layer and the surface coating layer, which is beneficial to efficient maintenance of the ceramic coating during inspection.

Shaped ceramic abrasive particles include a first surface having a perimeter having a perimeter comprising at least first and second edges. A first region of the perimeter includes the second edge and extends inwardly and terminates at two corners defining first and second acute interior angles. The perimeter has at most four corners that define acute interior angles. A second surface is disposed opposite, and not contacting, the first surface. A peripheral surface is disposed between and connects the first and second surfaces. The peripheral surface has a first predetermined shape. Methods of making the shaped ceramic abrasive particles, and abrasive articles including them are also disclosed.

Provided herein is an electrically conductive, chemically insulated network of nanofibers that includes first carbon nanofibers electrically connected to second carbon nanofibers to form an electrically conductive network, and second carbon nanofibers electrically connected to other second carbon nanofibers, wherein at least one of the second carbon nanofibers is in direct surface contact with another of the second carbon nanofibers; and an active material that provides electrochemical insulation on surfaces of the first carbon nanofibers and partial surfaces of at least a portion of the second carbon nanofibers, wherein the active material comprises at least 50% by weight of the electrically conductive, chemically insulated network, and wherein the active material provides electrochemical insulation to the entirety of the electrically conductive, chemically insulated network of nanofibers including the area between the first carbon nanofibers and the second carbon nanofibers.

The present disclosure relates to a negative temperature coefficient product comprising an electrically conductive percolation network of printable NTC material as particles in a cross-linked dielectric polymer matrix and to a method of manufacturing thereof. The particles comprising a spinel phase, preferably a C-spinel phase, having a general formula M.sub.3O.sub.4 comprising at least a first metal M.sup.I that is manganese and second metal M.sup.II that is nickel. In addition the particles include a nickel oxide phase. The printable NTC material can be dispersed in a printable NTC ink comprising a dispersant, from which the NTC product, e.g. a thermistor, can be formed, e.g., after drying of the dispersant. During processing the ink is kept at a temperature below 300° C. Optionally, the spinel phase comprises a further metal M.sup.III. The weight fraction of nickel oxide with respect to the overall mass of the printable NTC material is preferably in a range between one and twenty weight percent.

The present invention relates to solvothermal vapor synthesis methods for the crystallization of a phase from a mixture of selected inorganic or organic precursors in an unsaturated vapor-phase reaction medium.