The present invention relates to a method of producing metal nanoparticles and metal sulfide nanoparticles using a recombinant microorganism co-expressing metallothionein and phytochelatin synthase, which are heavy metal-adsorbing proteins, and to the use of metal nanoparticles and metal sulfide nanoparticles synthesized by the method. The present invention provides a method for synthesizing metal nanoparticles which have been difficult to synthesize by conventional biological methods. The present invention makes it possible to synthesize metal nanoparticles in an environmentally friendly and cost-effective manner, and also makes it possible to synthesize metal sulfide nanoparticles. In addition, even metal nanoparticles which could have been produced by conventional chemical or biological methods are produced in a significantly increased yield by use of the method of the present invention.

A powder for dust cores includes an aggregate of soft magnetic particles, each of which includes a soft magnetic metal particle, and a ferrite film that covers a surface of the soft magnetic metal particle and includes ferrite crystal grains having a spinel structure. A diffraction peak derived from the ferrite crystal grains exists in a powder X-ray diffraction pattern. By a method for producing a powder for dust cores, a raw material powder that includes an aggregate of soft magnetic metal particles is prepared. Furthermore, many ferrite fine particles are formed on a surface of each of the soft magnetic metal particles of the raw material powder. Additionally, the ferrite fine particles are coarsely crystallized through heat treatment to form a ferrite film, which includes ferrite crystal grains having a spinel structure, on the surface of the each of the soft magnetic metal particles.

The present specification provides a ferrite catalyst, a method for preparing the same and a method for preparing butadiene using the same.

A ferrite composition includes a main component and a sub-component. The main component includes 10.0 to 38.0 mol % of a Fe compound in terms of Fe.sub.2O.sub.3, 3.0 to 11.0 mol % of a Cu compound in terms of CuO, 39.0 to 80.0 mol % (excluding 39.0 mol %) of a Zn compound in terms of ZnO, and a balance of a Ni compound. The sub-component includes 10.0 to 23.0 parts by weight of a Si compound in terms of SiO.sub.2, 0 to 3.0 parts by weight (including 0 parts by weight) of a Co compound in terms of Co.sub.3O.sub.4, and 0.1 to 3.0 parts by weight of a Bi compound in terms of Bi.sub.2O.sub.3 with respect to 100 parts by weight of the main component.

Disclosed herein are magnetic nanoparticles, compositions and kits comprising the magnetic nanoparticles, methods of making the magnetic nanoparticles, and methods of using the magnetic nanoparticles to enrich biological targets.

Ferrite films, antennas including ferrite films, and methods of making thereof are provided. The methods can include tape casting of a slurry to produce a green film, wherein the slurry includes a ferrite powder, a dispersant, and a binder in a suitable solvent; and densifying the green film to produce the ferrite film having a thickness of 50 m to 5 mm. The methods can be used to make large area films, for example the films can have a lateral area of about 1000 cm.sup.2 to 3000 cm.sup.2. VHF/UHF antennas are including the ferrite films are also provided.

The invention relates to active electrode materials and to methods for the manufacture of active electrode materials. Such materials are of interest as active electrode materials in lithium-ion or sodium-ion batteries. The invention provides an active electrode material expressed by the general formula M1.sub.aM2.sub.2-aM3.sub.bNb.sub.34-bO.sub.87-c-dQ.sub.d.

Disclosed are embodiments of synthetic garnet materials for use in radiofrequency applications. In some embodiments, increased amounts of gadolinium can be added into specific sites in the crystal structure of the synthetic garnet by incorporating indium, a trivalent element. By including both indium and increased amounts of gadolinium, the dielectric constant can be improved. Thus, embodiments of the disclosed material can be advantageous in both above and below resonance applications, such as for isolators and circulators.

The present disclosure relates to a method of preparing a zinc ferrite catalyst. More particularly, the present invention relates to a method of preparing a zinc ferrite catalyst comprising a) a step of dissolving a zinc precursor and an iron (III) precursor in water to prepare an aqueous metal precursor solution; b) a step of precipitating a solid catalyst precursor while vaporizing water in the aqueous metal precursor solution; and c) a step of firing the precipitated solid catalyst precursor to prepare a zinc ferrite catalyst. In accordance with the present disclosure, the method of preparing a zinc ferrite catalyst can be simply carried out without a pH adjustment step and can secure reproducibility.

A method of preparing a catalyst for oxidative dehydrogenation that includes coprecipitation and injecting inert gas or air at a specific time point to reduce the ratio of an inactive -Fe.sub.2O.sub.3 crystal structure, thereby improving the activity of the catalyst. Also provided is a method of performing oxidative dehydrogenation using the catalyst. When oxidative dehydrogenation of butene is performed using the catalyst, side reaction may be reduced, and selectivity for butadiene may be improved, providing butadiene with high productivity.