Evergreen Solar, Inc.

Nanocomposix, Inc.

Trace Logic, Inc

Richard K Baldwin

Susan Kauzlarich

Steven J Oldenburg

Tyler W Blair

Andrew R Smith

The disclosed technology relates generally to material systems which include a plurality of particles and methods of making the same. The particles have a core and a shell which encapsulates the core and has at least one atomic element not included in the core. The cores of the particles have a median maximum dimension that is less than 10 microns and a median of at least one axial dimension that is between 10 nm and 500 nm. The shells of the particles have a median thickness that is less than 100 nm, a silicon concentration that is between 10% and 50% on the basis of the weight of the shells, and an aluminum concentration that is between 0.01% and 5% on the basis of the weight of the shells.

Encapsulated particles

Tracing fracking liquid in oil and gas wells using unique DNA sequences. For each of the DNA sequences, bonding to magnetic core particles, and encapsulating them with silica. Pumping the volumes of fracking liquid, each marked with one of the unique DNA sequences, into the well. Pumping fluids out of the well while taking fluid samples. For each of the plural fluid samples, gathering the silica encapsulated DNA using magnetic attraction with the magnetic core particles, dissolving away the silica shells, thereby separating the plural unique DNA sequences form the magnetic core particles, and analyzing the concentration of the unique DNA sequences in each of the plural fluid samples. Then, calculating the ratio of each of the volumes of fracking liquid recovered for each of the fluid samples, and thereby establishing the quantity of the volumes of fracking liquids removed from the fracture zones.

Oil and gas well fracture liquid tracing using DNA

A pyrophoric sheet that comprises oxidizable iron, non-combustible fibers, stiction-reducing coating where the sheet has a water content &#x3c;2%.

Pyrophoric sheet

Group IV nanocrystals, such as, for example, silicon nanocrysals and germanium nanocrystals, with chemically accessible surfaces are produced in solution reactions. Group IV halides can be reduced in organic solvents such as 1,2-dimethoxyethane (glyme), with soluable reducing agents to give halide-terminated group IV nanocrystals, which can then be easily functionalized with alkyl lithium, Grignard or other reagents to synthesize group IV nanocrystals having air and moisture stable surfaces. Synthesis can occur at ambient temperature and pressure.

Method for preparing group IV nanocrystals with chemically accessible surfaces

Silicon nanocrystals with chemically accessible surfaces are produced in solution in high yield. Silicon tetrahalide such as silicon tetrachloride (SiCl) can be reduced in organic solvents, such as 1,2-dimethoxyethane(glyme), with soluble reducing agents, such as sodium naphthalenide, to give halide-terminated (e.g., chloride-terminated) silicon nanocrystals, which can then be easily functionalized with alkyl lithium, Grignard or other reagents to give easily processed silicon nanocrystals with an air and moisture stable surface. The synthesis can be used to prepare alkyl-terminated nanocrystals at ambient temperature and pressure in high yield. The two-step process allows a wide range of surface functionality.

High yield method for preparing silicon nanocrystal with chemically accessible surfaces

Silicon nanocrystals with chemically accessible surfaces are produced in solution in high yield. Silicon tetrahalide such as silicon tetrachloride (SiCl) can be reduced in organic solvents, such as 1,2-dimethoxyethane (glyme), with soluble reducing agents, such as sodium naphthalenide, to give halide-terminated (e.g., chloride-terminated) silicon nanocrystals, which can then be easily functionalized with alkyl lithium, Grignard or other reagents to give easily processed silicon nanocrystals with an air and moisture stable surface. The synthesis can be used to prepare alkyl-terminated nanocrystals at ambient temperature and pressure in high yield. The two-step process allows a wide range of surface functionality.

Growing community of inventors

San Diego, CA, United States of America

Richard K Baldwin