A universal or all-purpose laser marking composition for forming satisfactorily dark laser marks on a wide variety of substrates is provided. The marking composition comprises an enhancer of nitrides, carbides, silicides, and combinations thereof. The enhancer may be selected one or more of ferromanganese, ferrosilicon, Fe.sub.xSi.sub.(1-x) where X can range from about 0.005 to 0.995, Fe.sub.5Si.sub.2, MgFeSi, SiC, CaSi, (Co)Mo, MoSi.sub.2, TiSi.sub.2, ZrSi.sub.2, WSi.sub.2, MnSi.sub.2, YSi, Cu.sub.5Si, Ni.sub.2Si, Fe.sub.3C, Fe.sub.7C.sub.3 and Fe.sub.2C, MoC, Mo.sub.2C, Mo.sub.3C.sub.2, YC.sub.2, WC, Al.sub.4C.sub.3, Mg.sub.2C, Mg.sub.2C.sub.3, CaC.sub.2, LaC.sub.2, Ta.sub.4C.sub.3, Fe.sub.2N, Fe.sub.3N, Fe.sub.4N, Fe.sub.7N.sub.3, Fe.sub.16N.sub.2, MoN, Mo.sub.2N, W.sub.2N, WN, WN.sub.2, and combinations thereof and combinations thereof. Upon disposing the marking composition on a substrate and exposing the marking composition to laser radiation, the marking composition absorbs the laser radiation, increases in temperature, chemically bonds with the substrate, and when formed on each of a metal, glass, ceramic, stone, and plastic substrates, the mark has a negative L dark contrast value of at least 1 compared to a mark formed by the marking composition without the enhancer.

Provided are an electromagnetic-wave absorbing composition that can favorably absorb electromagnetic waves of high frequencies in or above a millimeter-wave band and that can be applied to a desired portion in the form of a paste, and an easily deformable electromagnetic-wave absorber having flexibility. The electromagnetic-wave absorbing composition includes a rubber binder, a filler made of a particulate carbon material, and a magnetic iron oxide that magnetically resonates in a frequency band in or above a millimeter-wave band as an electromagnetic-wave absorbing material. The electromagnetic-wave absorber includes a rubber binder 1b, a filler 1c made of a particulate carbon material, and a magnetic iron oxide that magnetically resonates in a frequency band in or above a millimeter-wave band as an electromagnetic-wave absorbing material 1a, and is a nonresonant-type electromagnetic-wave absorber that is not provided with a reflective layer for reflecting incident electromagnetic waves.

A core component is made of a sintered body of an inorganic powder, in which the core component includes a columnar winding portion and a flange portion integrally formed with the winding portion at both axial ends of the winding portion, and a cutting level difference (Rc) of a roughness curve representing a difference between a cutting level at 25% loading length rate in the roughness curve and a cutting level at 75% loading length rate in the roughness curve of a surface of the winding portion is 0.2 m or more and 2 m or less.

The present invention relates to a process for preparing a rodlike magnetic ferroferric oxide (Fe.sub.3O.sub.4) material and use thereof. The preparation includes the following steps: step 1: magnetic Fe3O4 nanoparticle preparation; and step 2: self-assembly of magnetic Fe3O4@SiO2 nanoparticles into a rodlike magnetic material. When in use, the rodlike magnetic Fe.sub.3O.sub.4 material prepared by the process according to claim 1 is used in micro- and nano-motors, which can implement rotation and deflection in an external magnetic field. The present invention provides a process for preparing a rodlike magnetic Fe.sub.3O.sub.4 material. The rodlike magnetic ferroferric oxide material prepared by the process is suitable for mass production on an industrial scale, featuring identifiable direction of the magnetic moment, strong magnetism, good magnetic response, simple process, and low cost.

The -iron oxide type ferromagnetic powder contains Fe, a metal element selected from the group consisting of monovalent metal elements and divalent metal elements at a content rate within a range of 0.2 to 16.5 at % with respect to 100.0 at % of Fe, and a pentavalent metal element at a content rate within a range of 0.2 to 7.5 at % with respect to 100.0 at % of Fe, in which a total content rate of metal elements other than Fe is within a range of 2.5 to 24.0 at % with respect to 100.0 at % of Fe.

A sintered ferrite magnet represented by the general formula of Ca.sub.1-xLa.sub.xFe.sub.2n-y-zCo.sub.yZn.sub.z expressing the atomic ratios of metal elements of Ca, La, Fe, Co and Zn, wherein x, y, z, and n [2n is a molar ratio represented by 2n=(Fe+Co+Zn)/(Ca+La)] meet 0.4<x<0.75, 0.15y<0.4, 0.11z<0.4, 0.26(y+z)<0.65, and 3n6.

A carrier core material formed with ferrite particles, the skewness Rsk of the particle is equal to or more than 0.40 but equal to or less than 0.20, and the kurtosis Rku of the particle is equal to or more than 3.20 but equal to or less than 3.50. Here, the maximum height Rz of the particle is equal to or more than 2.20 m but equal to or less than 3.50 m. Moreover, the ferrite particle contains at least either of Mn and Mg elements. In this way, cracking or chipping in a concave-convex portion of a particle surface is unlikely to occur, and moreover, the amount of coating resin used can be reduced without properties such as electrical resistance being lowered.

A multi-compartment microcapsule emits photons when subjected to a stimulus. In some embodiments, the multi-compartment microcapsules have first and second compartments separated by an isolating structure adapted to rupture in response to the stimulus, wherein the first and second compartments contain reactants that come in contact and react to produce photons when the isolating structure ruptures.

A multi-compartment microcapsule emits photons when subjected to a stimulus. In some embodiments, the multi-compartment microcapsules have first and second compartments separated by an isolating structure adapted to rupture in response to the stimulus, wherein the first and second compartments contain reactants that come in contact and react to produce photons when the isolating structure ruptures.

A self-healing polymeric material includes a polymeric matrix material, wherein dispersed within the polymeric matrix material is a mixture of materials that includes monomers and a photoinitiator, and a plurality of light generating microcapsules dispersed in the polymeric matrix material. Each light generating microcapsule encapsulates multiple reactants that undergo a chemiluminescent reaction. The chemiluminescent reaction generates a photon having a wavelength within a particular emission range that is consistent with an absorption range of the photoinitiator.