Iowa State University Research Foundation, Inc.

California Institute of Technology

Atlas Scientific

Vitalij K Pecharsky

Karl A Gschneidner, Jr

Viktor Balema

Ihor Hlova

Arjun K Pathak

Marek Pruski

Yaroslav Mudryk

Alexandra O Pecharsky

Shalabh Gupta

Oleksandr Dolotko

David C Jiles

Duane D Johnson

Prashant Singh

Sonal Padalkar

Tian Lan

Jerzy W Wiench

Iver E Anderson

Ratnakumar V Bugga

Robert L Terpstra

Timothy W Ellis

Brent T Fultz

Jason Ting

Magundappa Ravi L Hadimani

Seong-Jae Lee

Robert C Bowman

Charles K Witham

Takeshi Kobayashi

Shane Harstad

Henrique Neves Bez

Nikolai A Zarkevich

Julie Slaughter-Zrostlik

Andra Castle

Lucas Griffith

Agata Czernuszewicz

Alexandra O Tsokol

Jack O Moorman

Anis Biswas

A magnetocaloric material comprising a La—Fe—Si based alloy composition that is compositionally modified to include a small but effective amount of at least one of Al, Ga, and In to improve mechanical stability of the alloy (substantially reduce alloy brittleness), improve thermal conductivity, and preserve comparable or provide improved magnetocaloric effects. The alloy composition may be further modified by inclusion of at least one of Co, Mn, Cr, and V as well as interstitial hydrogen.

Modified La—Fe—Si magnetocaloric alloys

A cathode is provided for electrolysis of water wherein the cathode material comprises a multi-principal element, transition metal dichalcogenide material that has four or more chemical elements and that is a single phase, solid solution. The pristine cathode material does not contain platinum as a principal (major) component. However, a cathode comprising a transition metal dichalcogenide having platinum (Pt) nanosized islands or precipitates disposed thereon is also provided.

Electrocatalyst for water electrolysis

The elastocaloric effect underpins a promising solid-state heat pumping technology that, when adopted for commercial and residential applications, can revolutionize the cooling and heating industry due to low environmental impact and substantial energy savings. Known operational demonstration devices based on the elastocaloric effect suffer from low endurance of materials and, in most experimental systems, from large footprints due to bulky actuators required to provide sufficient forces and displacements. We demonstrate a new approach which has the potential to enable a more effective exploitation of the elastocaloric effect by reducing the forces required for actuation. Thin strips of NiTi were incorporated into composite structures with base polymer, such that bending the structures results in either exclusively compression or exclusively tension applied to the elastocaloric strips. The structures allow compression of thin elastocaloric strips without buckling, realize more than 50% reduction in required forces for a given strain compared with axial loading, and open up a wide range of possibilities for compact, efficient elastocaloric devices.

Low-force compressive and tensile actuation for elastocaloric heat pumps

A method embodiment involves preparing single metal or mixed transition metal chalcogenide using exfoliation of two or more different bulk transition metal dichalcogenides in a manner to form an intermediate hetero-layered transition metal chalcogenide structure, which can be treated to provide a single-phase transition metal chalcogenide.

Preparation of metal chalcogenides

A method is provided of making a magnetocaloric alloy composition comprising Ni, Co, Mn, and Ti, which preferably includes certain beneficial substitutional elements, by melting the composition and rapidly solidifying the melted composition at a cooling rate of at least 100 K/second (Kelvin/second) to improve a magnetocaloric property of the composition. The rapidly solidified composition can be heat treated to homogenize the composition and annealed to tune the magneto-structural transition for use in a regenerator.

Highly tunable, inexpensive and easily fabricated magnetocaloric materials

Certain method embodiments are described and useful for recycling permanent magnet materials (e.g. permanent magnet alloys) and battery materials (e.g. battery electrode materials) to extract critical and/or valuable elements including REEs, Co and Ni. Method embodiments involve reacting such material with at least one of an ammonium salt and an iron (III) salt to achieve at least one of a liquid phase chemical reaction and a mechanochemical reaction.

Chemical dismantling of permanent magnet material and battery material

A magnetocaloric material comprising a La&#x2014;Fe&#x2014;Si based alloy composition that is compositionally modified to include a small but effective amount of at least one of Al, Ga, and In to improve mechanical stability of the alloy (substantially reduce alloy brittleness), improve thermal conductivity, and preserve comparable or provide improved magnetocaloric effects. The alloy composition may be further modified by inclusion of at least one of Co, Mn, Cr, and V as well as interstitial hydrogen.

Modified La&#x2014;Fe&#x2014;Si magnetocaloric alloys

In some examples, a method of forming alane (AlH), the method comprising reacting one of: 1) a MAlH, wherein M is an alkali metal; 2) alkali-metal hydride, MH; or 3) alkali-metal with one or more aluminum halides (AlX, where X is a halogen), via a mechanochemical process, to form the alane, wherein the reaction is substantially solvent free and carried out in an environment with a temperature between approximately 250 K and approximately 330 K.

Mechanochemical synthesis of alane

A particle usable as Tand Tcontrast agents is provided. The particle is a gadolinium silicide (GdSi) particle that is ferromagnetic at temperatures up to 290 K and is less than 2 &#x3bc;m in diameter. An MRI contrast agent that includes a plurality of gadolinium silicide (GdSi) particles that are less than 1 &#x3bc;m in diameter is also provided. A method for creating gadolinium silicide (GdSi) particles is also provided. The method includes the steps of providing a GdSibulk alloy; grinding the GdSibulk alloy into a powder; and milling the GdSibulk alloy powder for a time of approximately 20 minutes or less.

Room temperature ferromagnetic gadolinium silicide nanoparticles

A method is provided for making alkali metal hydrides by mechanochemically reacting alkali metal and hydrogen gas under mild temperature (e.g room temperature) and hydrogen pressure conditions without the need for catalyst, solvent, and intentional heating or cooling.

Method of making alkali metal hydrides

A multi-stage cryocooler having a relatively low temperature stage to cool to less than about 15K and having a regenerator including a ductile intermetallic compound including one or more rare earth elements and one or more non-rare earth metals.

Low temperature cryocooler regenerator of ductile intermetallic compounds

An alloy made of heat treated material represented by Gd(SiGe)where 0.47&#x2266;x&#x2266;0.56 that exhibits a magnetic entropy change (&#x2212;&#x394;S) of at least 16 J/kg K, a magnetostriction of at least 2000 parts per million, and a magnetoresistance of at least 5 percent at a temperature of about 300K and below, and method of heat treating the material between 800 to 1600 degrees C. for a time to this end.

Method of making active magnetic refrigerant materials based on Gd-Si-Ge alloys

The present invention provides a method of preparing a phosphonium salt of the formula [RRRP&#x2014;CRRR]X, comprising ball-milling a phosphine of the formula RRRP with a compound of the formula XCRRR; a method of preparing a phosphorus ylide of the formula RRRP&#x2550;CRR, comprising ball-milling a phosphonium salt of the formula [RRRP&#x2014;HCRR]X in the presence of a base; and a method of preparing an olefin of the formula RRC&#x2550;CRH or RRC&#x2550;CRR, comprising ball-milling a phosphorus ylide of the formula RRRP&#x2550;CRRwith a compound of the formula RC(O)H or RC(O)R. The inventive method produces phosphonium salts and phosphorus ylides by mechanical processing solid reagents under solvent-free conditions. The advantages of the present invention over conventional solution methods, include: (1) extremely high selectivity; (2) high yields; (3) low processing temperatures; (4) simple and scalable reactions using commercially available equipment; and (5) the complete elimination of solvents from the reaction.

Solvent-free mechanochemical preparation of phosphonium salts, phosphorus ylides, and olefins

Growing community of inventors

Ames, IA, United States of America

Vitalij K Pecharsky