Abstract: A heterogeneous catalyst for substrate-directed hydrogenation includes bimetallic nanoparticles of M1-M2, wherein M1 is a noble metal and M2 is a first-row transition metal. The bimetallic nanoparticles are on a substrate and atoms of both the noble metal and the first-row transition metal are distributed across surfaces of the bimetallic nanoparticles. The heterogeneous catalyst may be produced by providing M1-M2 bimetallic nanoparticles on a substrate to produce an intermediate composition, and performing a reduction process on the intermediate composition such that atoms of both the noble metal (M1) and the first-row transition metal (M2) are distributed across surfaces of the bimetallic nanoparticles and thereby form the heterogeneous catalyst. The catalyst may be used for performing directed hydrogenation of a substrate.

Abstract: A heterogeneous catalyst for substrate-directed hydrogenation includes bimetallic nanoparticles of M1-M2, wherein M1 is a noble metal and M2 is a first-row transition metal. The bimetallic nanoparticles are on a substrate and atoms of both the noble metal and the first-row transition metal are distributed across surfaces of the bimetallic nanoparticles. The heterogeneous catalyst may be produced by providing M1-M2 bimetallic nanoparticles on a substrate to produce an intermediate composition, and performing a reduction process on the intermediate composition such that atoms of both the noble metal (M1) and the first-row transition metal (M2) are distributed across surfaces of the bimetallic nanoparticles and thereby form the heterogeneous catalyst. The catalyst may be used for performing directed hydrogenation of a substrate.

Abstract: Beams of laser light trap and cool cesium atoms in a small vapor cell and put the atoms in a particular quantum mechanical state. The lasers are then configured so as to launch the atoms upward by shifting the frequencies of the vertically propagating lasers. The atoms pass through a microwave waveguide during both their ascent and descent. The microwave field is applied briefly each time the atoms are in the center of the waveguide so that the microwaves excite the cesium "clock" transition. Once the atoms have fallen back to where they started, the laser fields are turned on in a particular sequence. The fraction of the atoms that make a quantum mechanical transition is measured by observing the laser light scattered by the atoms. That signal indicates how close the microwave frequency is to the atomic transition. The laser cooling reduces the relative motion of the atoms so that the atoms can be observed longer. The resulting atomic resonance measured is much narrower.

Abstract: Beams of laser light trap and cool cesium atoms in a small vapor cell and put the atoms in a particular quantum mechanical state. The lasers are then configured so as to launch the atoms upward by shifting the frequencies of the vertically propagating lasers. The atoms pass through a microwave waveguide during both their ascent and descent. The microwave field is applied briefly each time the atoms are in the center of the waveguide so that the microwaves excite the cesium "clock" transition. Once the atoms have fallen back to where they started, the laser fields are turned on in a particular sequence. The fraction of the atoms that make a quantum mechanical transition is measured by observing the laser light scattered by the atoms. That signal indicates how close the microwave frequency is to the atomic transition. The laser cooling reduces the relative motion of the atoms so that the atoms can be observed longer. The resulting atomic resonance measured is much narrower.