A hexagonal boron nitride powder whose maximum absorption peak within the range of 3,100 to 3,800 cm.sup.1 of the diffuse reflectance fourier transform infrared spectrum is existent at 3,530 to 3,590 cm.sup.1 and which is able to provide high heat conductivity, dielectric strength and copper foil peel strength to a resin composition obtained by filling the powder into a resin, and a process for producing the above boron nitride powder by mixing together an oxygen-containing boron compound, a carbon source having a sulfur concentration of 1,000 to 10,000 ppm and an oxygen-containing calcium compound in a specific ratio and reduction nitriding the mixture.

The present invention relates to a composite material for use as a thermal interface material between a heat source and a heat sink. The present invention also relates to the method of synthesizing such a composite material. The composite material has high thermal conductivity, low thermal resistance and functions as an adhesive.

Described herein are apparatus, systems, and methods for the continuous production of BNNT fibers, BNNT strands and BNNT initial yarns having few defects and good alignment. BNNTs may be formed by thermally exciting a boron feedstock in a chamber in the presence of pressurized nitrogen. BNNTs are encouraged to self-assemble into aligned BNNT fibers in a growth zone, and form BNNT strands and BNNT initial yarns, through various combinations of nitrogen gas flow direction and velocities, heat source distribution, temperature gradients, and chamber geometries.

As disclosed herein, the viscoelastic performance of boron nitride nanotube (BNNT) materials may be enhanced and made into useful formats by utilizing purified BNNTs, aligned BNNTs, isotopically enhanced BNNTs, and density controlled BNNT material. Minimizing the amounts of boron particles, a-BN particles, and h-BN nanocages, and optimizing the h-BN nanosheets has the effect of maximizing the amount of BNNT surface area present that may interact with BNNTs themselves and thereby create the nanotube-to-nanotube friction that generates the viscoelastic behavior over temperatures from near absolute zero to near 1900 K. Aligning the BNNT molecular strands with each other within the BNNT material also generates enhanced friction surfaces. The transport of phonons along the BNNT molecules may be further enhanced by utilizing isotopically enhanced BNNTs.

A chemical vapor deposition process comprising heating a porous metal template at a temperature range of 500 to 2000 C.; and passing a gas mixture comprising a carrier gas carrying along a vapor of an organometallic compound and at least one of a carbon precursor gas and a boron nitride precursor gas through the heated metal template is provided. The heating temperature causes the decomposition of the organometallic compound vapor into metal particles, the carbon precursor gas into graphene domains, and/or the boron nitride precursor gas into hexagonal-boron nitride domains. The graphene domains and/or the hexagonal-boron nitride domains nucleate and grow on the metal particles and the metal template to form a three-dimensional interconnected porous network of graphene and/or the hexagonal-boron nitride. A foam-like structure produced by a process as described above is also provided. A foam-like structure as described above for use in electrochemistry, solar cells, filler, thermal interface material, sensing or biological applications is further provided.

A negative electrode active material includes a layered compound that includes: a plurality of layers and calcium located between the plurality of layers; each of the plurality of layers containing carbon and boron and further containing nitrogen or phosphorus.

Described herein are apparatus, systems, and methods for the continuous production of BNNT fibers, BNNT strands and BNNT initial yarns having few defects and good alignment. BNNTs may be formed by thermally exciting a boron feedstock in a chamber in the presence of pressurized nitrogen. BNNTs are encouraged to self-assemble into aligned BNNT fibers in a growth zone, and form BNNT strands and BNNT initial yarns, through various combinations of nitrogen gas flow direction and velocities, heat source distribution, temperature gradients, and chamber geometries.

A method for purifying solid borazane (NH.sub.3BH.sub.3 (s)) includes a) bringing solid borazane (NH.sub.3BH.sub.3 (s)) containing impurities into contact with a stream of gaseous ammonia (NH.sub.3 (g)) to obtain, by selective liquefaction of the borazane, a liquid phase containing liquefied borazane and ammonia and a solid phase constituted of at least a part of the impurities, b) separating the liquid and solid phases for recovery of the liquid phase, on the one hand, and of the solid phase, on the other hand; c) removing the ammonia from the recovered liquid phase, this removal causing precipitation of the purified borazane (NH.sub.3BH.sub.3 (s)); and d) recovering the purified precipitated borazane (NH.sub.3BH.sub.3 (s)).

Provided are hexagonal boron nitride aggregated particles and hexagonal boron nitride powder, each of which can be filled into a resin to produce a resin composition with an extremely high dielectric strength and thermal conductivity, and to reduce the density of the resin composition. Provided are hexagonal boron nitride aggregated particles, in which aggregated particles of hexagonal boron nitride primary particles have a longer diameter ranging from 5 to 10 ?m, a longer diameter/shorter diameter ranging from 1.0 to 1.3, and a circularity within a range from 0.3 to 0.8, and a maximum diameter of primary particles which can be confirmed on the surface of the aggregated particles on an SEM observation image at 10,000 magnification is 4 ?m or less. Provided is a hexagonal boron nitride powder including aggregated particles of hexagonal boron nitride primary particles, in which a particle size (D.sub.50) at a cumulative volume frequency of 50% in a particle size distribution as measured by a wet laser diffraction particle size distribution analysis is from 5 to 150 ?m, a volume-based median diameter of pores as measured by a mercury porosimetry is 3.0 ?m or less, and a content of impurity elements is 500 ppm or less.

To provide an electrolyte for a storage device capable of lowering the electric resistance and maintaining a high capacity even after charging and discharging are repeatedly carried out, and a storage device. An electrolyte for a storage device, which comprises a lithium-containing complex compound represented by the following formula (1), (2), (3), (4) or (5):
(Li).sub.m(A).sub.n(UF.sub.x).sub.y(1)
(Li).sub.m(Si).sub.n(O).sub.q(UF.sub.x).sub.y(2)
wherein A is O, S, P or N; U is a boron atom or a phosphorus atom; m and n are each independently from 1 to 6; q is from 1 to 12; x is 3 or 5; and y is from 1 to 6;
(Li).sub.m(O).sub.n(B).sub.p(OWF.sub.q).sub.x(3)
wherein W is a boron atom or a phosphorus atom; m, p and x are each independently from 1 to 15; n is from 0 to 15; and q is 3 or 5;
(Li).sub.m(B).sub.p(O)n(OR).sub.y(OWF.sub.q).sub.x(4)
wherein W is a boron atom or a phosphorus atom; n is from 0 to 15; p, m, x and y are each independently from 1 to 12; q is 3 or 5; and R is hydrogen, an alkyl group, an alkenyl group, an aryl group, a carbonyl group, a sulfonyl group or a silyl group, and such a group may have a fluorine atom, an oxygen atom or other substituent;
(Li).sub.m(O).sub.n(B).sub.p(OOC-(A).sub.z-COO).sub.y(OWF.sub.q).sub.x(5)
wherein W is a boron atom or a phosphorus atom, A is a C.sub.1-6 allylene group, alkenylene group or alkynylene group, a phenylene group, or an alkylene group having an oxygen atom or a sulfur atom in its main chain; m, p, x and y are each independently from 1 to 20; n is from 0 to 15; z is 0 or 1; and q is 3 or 5.