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At least 307 records · Page 17

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DOE OSTI2021

Lipophilic guanidinium compounds for removal of oxyanions from aqueous solutions

Methods for removing an oxyanion from an aqueous source containing said oxyanion, comprising contacting said aqueous source with an aqueous-insoluble hydrophobic solution containing an oxyanion extractant compound dissolved in an aqueous-insoluble hydrophobic solvent to result in formation of an oxyanion salt of said extractant compound and extraction of said oxyanion salt into said aqueous-insoluble hydrophobic solution, wherein said extraction results in an extraction affinity (D) of said oxyanion of at least 1, wherein D is the concentration ratio of said oxyanion in the organic phase divided by the concentration of said oxyanion in the aqueous phase; wherein said extractant compound has the following composition: wherein at least one of R1-R10 is or contains a hydrocarbon (R) group containing at least 4, 5, 6, 7, 8, 9, 10, 11, or 12 carbon atoms.

Williams, Neil John↗

DOE OSTI2021

Methods and apparatus for additively manufacturing structures using in situ formed additive manufacturing materials

A method of additively manufacturing a structure comprises nuclear reactor comprises disposing a feed material on a surface of a substrate in a reaction vessel, disposing at least one material formulated and configured to react with the feed material in the reaction vessel, and exposing the feed material and the at least one material to energy from an energy source to react the feed material and the at least one material to form an additive manufacturing material and reaction by-products. The additive manufacturing material is separated from the reaction by-products and exposed to energy from the energy source to form inter-granular bonds between particles of the additive manufacturing material and form a layer of a structure comprising the additive manufacturing material. Related apparatuses and methods are disclosed.

van Rooyen, Isabella J.↗

DOE OSTI2021

Three dimensional vertically structured electronic devices

According to one embodiment, an apparatus includes at least one vertical transistor, where the at least one vertical transistor includes: a substrate including a semiconductor material; an array of three dimensional (3D) structures above the substrate; and an isolation region positioned between the 3D structures. Each 3D structure includes the semiconductor material. Each 3D structure also includes a first region having a first conductivity type and a second region having a second conductivity type, where the second region includes a portion of at least one vertical sidewall of the 3D structure.

Conway, Adam↗

DOE OSTI2021

Coating for improved surface finish

A coating includes: at least 34.9 percent by mass silicon dioxide; at least 9.1 percent by mass aluminum oxide; and at least 16.1 percent by mass yttrium oxide.

Hafner, Matthew Troy↗

DOE OSTI2021

Systems and methods for producing nitriles

An aspect of the present disclosure is a method that includes a first reacting a molecule from at least one of a carboxylic acid, an ester of a carboxylic acid, and/or an anhydride with ammonia to form a nitrile, where the first reacting is catalyzed using an acid catalyst. In some embodiments of the present disclosure, the molecule may include at least one of acetic acid, lactic acid, and/or 3-hydroxyproprionic acid (3-HPA). In some embodiments of the present disclosure, the molecule may include at least one of methyl acetate, ethyl lactate, and/or ethyl 3-hydroxypropanoate (ethyl 3-HP). In some embodiments of the present disclosure, the anhydride may be acetic anhydride.

Karp, Eric M.↗

DOE OSTI2021

Method and system for in situ cross-linking of materials to produce three-dimensional features via electron beams from mobile accelerators

A method and system for in situ cross-linking of polymers, Bitumen, and other materials to produce arbitrary functional or ornamental three-dimensional features using electron beams provided by mobile accelerators comprises defining a desired pattern for imparting on a target area, mapping the target area, defining at least one discrete voxel in the target area according to the desired pattern to be imparted on the target area, assigning an irradiation value to each of the at least one discrete voxels, and delivering a dose of irradiation to each of the at least one discrete voxels according to the assigned irradiation value.

43 PARTICLE ACCELERATORS↗

DOE OSTI2021

Zeolitic catalytic conversion of alcohols to olefins

A catalyst composition for converting an alcohol to olefins, the catalyst composition comprising the following components: (a) beta zeolite; (b) at least one element selected from the group consisting of zinc, magnesium, calcium, strontium, sodium, and potassium; and (c) at least one element selected from the group consisting of hafnium, yttrium, zirconium, tantalum, niobium, and tin; wherein the components (b) and (c) are independently within or on a surface of said beta zeolite. The catalyst may also further include component (d), which is copper or silver. Also described herein is a method for converting an alcohol to one or more olefinic compounds, the method comprising contacting the alcohol with a catalyst at a temperature of at least 100° C. and up to 500° C. to result in the alcohol being converted to the one or more olefinic compounds.

Li, Zhenglong↗

DOE OSTI2021

Current generation from radiation with diamond diode-based devices for detection or power generation

Diamond diode-based devices are configured to convert radiation energy into electrical current, useable for sensing (i.e., detection) or delivery to a load (i.e., energy harvesting). A diode-based detector includes an intrinsic diamond layer arranged between p-type diamond and n-type diamond layers, with the detector further including at least one of (i) a boron containing layer arranged proximate to the n-type and/or the intrinsic diamond layers, or (ii) an intrinsic diamond layer thickness in a range of 10 nm to 300 microns. A diode-based detector may be operated in a non-forward biased state, with a circuit used to transmit a current pulse in a forward bias direction to reset a detection state of the detector. An energy harvesting device may include at least one p-i-n stack (including an intrinsic diamond layer between p-type diamond and n-type diamond layers), with a radioisotope source arranged proximate to the at least one p-i-n stack.

Holmes, Jason M.↗

DOE OSTI2021

Biodegradable surfactants and related compositions, methods and systems

Biodegradable surfactants are described, in which an amphiphilic heteroatom containing hydrocarbon optionally comprising at least one counterion (Z), and related compositions, methods and systems. Biodegradable surfactant described herein has an aHLB value in accordance with equation (1): aHLB=20*Gh/(Gh−Gt) (1) wherein Gh is the Group Number of a hydrophilic head portion of the biodegradable surfactant optionally comprising the at least one counterion (Z), and Gt is the Group Number of a hydrophobic tail portion of the biodegradable surfactant. A biodegradable surfactant in the sense of the disclosure can be tuned to a set hydrophilic-lipophilic balance (aHLB) by selectively modifying at least one tuning moiety of the biodegradable surfactants to provide tuned biodegradable surfactants having an increase or decrease in their adjusted hydrophilic-lipophilic balance (aHLB).

Lyman, Mathew Gerald↗

DOE OSTI2021

Composite energy-absorbing assembly

An energy-absorbing assembly includes a housing and a plurality of discrete energy-absorbing elements. The housing includes a first wall and a second wall. The first wall and the second wall are spaced apart from one another to at least partially define an interior compartment. Each element of the plurality of energy-absorbing elements includes a polymer and a plurality of reinforcing fibers. The plurality of energy-absorbing elements is at least partially disposed within the interior compartment and fixed to the housing. Each energy-absorbing element of the plurality of energy-absorbing elements includes an elongated hollow structure extending between a first end and a second end. Each elongated hollow structure defines a longitudinal axis extending nonparallel to at least one of the first wall and the second wall. In various alternative aspects, each energy-absorbing element may include a transverse wall.

Rodgers, William R.↗

DOE OSTI2021

Durable graphene oxide membranes

Embodiments described herein relate generally to durable graphene oxide membranes for fluid filtration. For example, the graphene oxide membranes can be durable under high temperatures non-neutral pH, and/or high pressures. One aspect of the present disclosure relates to a filtration apparatus comprising: a support substrate, and a graphene oxide membrane disposed on the support substrate. The graphene oxide membrane has a first lactose rejection rate of at least 50% with a first 1 wt % lactose solution at room temperature. The graphene oxide membrane has a second lactose rejection rate of at least 50% with a second 1 wt % lactose solution at room temperature after the graphene oxide membrane is contacted with a solution that is at least 80° C. for a period of time.

Frayne, Stephen↗

DOE OSTI2021

Method and system for in situ cross-linking of materials to produce three-dimensional features via electron beams from mobile accelerators

Sauers, Aaron↗

DOE OSTI2021

Anode catalyst suitable for use in an electrolyzer

An anode catalyst suitable for use in an electrolyzer. The anode catalyst includes a support and a plurality of catalyst particles disposed on the support. The support may include a plurality of metal oxide or doped metal oxide particles. The catalyst particles, which may be iridium, iridium oxide, ruthenium, ruthenium oxide, platinum, and/or platinum black particles, may be arranged to form one or more aggregations of catalyst particles on the support. Each of the aggregations of catalyst particles may include at least 10 particles, wherein each of the at least 10 particles is in physical contact with at least one other particle. The support particles and their associated catalyst particles may be dispersed in a binder.

Xu, Hui↗

DOE OSTI2021

High-temperature NMR MAS probe with optimized temperature gradient across sample rotor

A rotor housing assembly for NMR spectroscopy. An elongate rotor has a distal drive end, a proximal end and an internal sample space positioned along its length between the drive and proximal ends. The rotor is driveable about a rotation axis by a drive gas flow. A rotor housing has an interior space in which the rotor is at least partially received. At least one first heated gas flow inlet is positioned opposite the internal sample space, through which a first heated gas flow is controllably flowable into the interior space to heat it and the rotor. At least a pair of spaced apart second heated gas flow outlets are axially spaced from the first heated gas flow inlet to controllably convey a second heated gas flow to heat distal and proximal areas of the sample space to minimize a temperature gradient extending axially within the sample space.

Mehta, Hardeep S.↗

DOE OSTI2021

Ionizing-radiation beamline monitoring system

Embodiments are directed generally to an ionizing-radiation beamline monitoring system that includes a vacuum chamber structure with vacuum compatible flanges through which an incident ionizing-radiation beam enters the monitoring system. Embodiments further include at least one scintillator within the vacuum chamber structure that can be at least partially translated in the ionizing-radiation beam while oriented at an angle greater than 10 degrees to a normal of the incident ionizing-radiation beam, a machine vision camera coupled to a light-tight structure at atmospheric/ambient pressure that is attached to the vacuum chamber structure by a flange attached to a vacuum-tight viewport window with the camera and lens optical axis oriented at an angle of less than 80 degrees with respect to a normal of the scintillator, and at least one ultraviolet (“UV”) illumination source facing the scintillator in the ionizing-radiation beam for monitoring a scintillator stability comprising scintillator radiation damage.

Friedman, Peter S.↗

DOE OSTI2021

System and method for characterization of retrofit opportunities in building using data from communicating thermostats

Systems and methods for characterization of retrofit opportunities are described. The methods may comprise computing, using at least one computing device disposed remote from a building and based at least in part on heating, ventilation and air conditioning (HVAC) runtime data associated with the building, one or more thermal characteristics of the building. In some embodiments, a model-predicted indoor temperature may be fitted against thermal data measured by a thermostat at the building. The thermal characteristic of the building may comprise a thermal insulation, an air leakage rate and/or an HVAC efficiency. The method may be used to determine, using the at least one computing device, suitability of the building for a retrofit opportunity to improve energy efficiency of the building. Determining the suitability may comprise evaluating the one or more thermal characteristics. The HVAC runtime data may be computed based on data received from a thermostat or a meter, such as an electric or a gas meter.

Zeifman, Michael↗

DOE OSTI2021

System and method for characterization of retrofit opportunities in building using data from interval meters

Zeifman, Michael↗

DOE OSTI2021

Superlattice structure including two-dimensional material and device including the superlattice structure

Provided are a superlattice structure including a two-dimensional material and a device including the superlattice structure. The superlattice structure may include at least two different two-dimensional (2D) materials bonded to each other in a lateral direction, and an interfacial region of the at least two 2D materials may be strained. The superlattice structure may have a bandgap adjusted by the interfacial region that is strained. The at least two 2D materials may include first and second 2D materials. The first 2D material may have a first bandgap in an intrinsic state thereof. The second 2D material may have a second bandgap in an intrinsic state thereof. An interfacial region of the first and second 2D materials and an adjacent region may have a third bandgap between the first bandgap and the second bandgap.

Lee, Minhyun↗