USA As Represented by Secretary of the Navy

Government of the United States of America, As Represented by the Secretary of Commerce

Glenn Emerson Holland

John F Seely

Craig N Boyer

Samuel Martin Stavis

J Alexander Liddle

Tanya Gupta

Andrei A Kolmakov

A multidimensional printer makes a multidimensional structure from a liquid composition and includes: an energetic crosslinking particle source; a vacuum chamber that receives energetic crosslinking particles from the energetic crosslinking particle source; a membrane that transmits the energetic crosslinking particles; and a sample chamber that: receives a liquid composition that includes a solvent and polymers, the polymers including a cross-linkable moiety subjected to the energetic crosslinking particles such that portions of the polymers proximate to the cross-linkable moieties subjected to the energetic crosslinking particles crosslink to form a solid crosslinked polymer structure, wherein the membrane isolates a vacuum of the vacuum chamber from vapor of the liquid composition in the sample chamber.

Multidimensional printer

A non-vacuum, non-contact spinner wafer chuck including: a basal member including; a fastener receiver that receives a fastener; a chuck collar including: an inner collar wall; and an outer collar wall; and an engagement surface that: receives and engages a wafer; a wafer engagement cam including: an engagement face that engages the wafer; an index cam disposed on the chuck collar and comprising: an index face that faces toward the fastener receiver and that engages the wafer; and a spinner engager disposed on the spinner-side surface of the basal member and comprising: a spinner arm receiver bounded by a wall and that receives a spinner of the wafer processing machine, wherein the wafer engagement cam and the index cam engage the wafer and maintains an orientation of the wafer with respect to the index cam in response to rotation of the wafer relative to the non-vacuum, non-contact spinner wafer chuck.

Non-vacuum, non-contact spinner wafer chuck

A fluid sampler includes: a sample cell that includes: a substrate comprising: a first port; a second port in fluid communication with the first port; a viewing reservoir in fluid communication with the first port and the second port and that receives the fluid from the first port and communicates the fluid to the second port, the viewing reservoir including: a first view membrane; a second view membrane; and a pillar interposed between the first view membrane and second view membrane, the pillar separating the first view membrane from the second view membrane at a substantially constant separation distance such that a volume of the viewing reservoir is substantially constant and invariable with respect to a temperature and invariable with respect to a pressure to which the sample cell is subjected.

Vacuum compatible fluid sampler

A two-wire metal vapor vacuum arc (MeVVA) vacuum head includes an upper housing and a lower vacuum housing. The lower vacuum housing includes a plurality of ports, a vacuum space, and a first grid positioned in the vacuum space. A plurality of electrodes are positioned in the ports with a first end with an electrical contact area extending into the upper housing, and a second end extending into the vacuum space with an exposed electrical discharge area spaced from the first grid. An electrode of opposite polarity is positioned in one of the lower housing ports with a first end extending into the upper housing and a second end attached to the first grid. An extractor grid is positioned adjacent to the first grid, an electrode selector is operatively connected to the plurality of electrodes, and a trigger generator circuit is connected to an input of the electrode selector.

Metal vapor vacuum arc ion source

A trigger circuit is provided for a trigger system for a Marx generator column. The column includes a plurality of metal electrode pairs wherein the electrodes of each pair are spaced to form a spark gap therebetween and a capacitor is connected across each gap. The trigger system includes a three electrode (trigatron) spark gap switch forming the first spark gap of the Marx generator column. The triggering circuit includes a trigger transformer having primary and secondary windings. The secondary winding is connected through a connecting cable to a blocking capacitor of an input circuit of the trigatron switch. A charging capacitor is connected to an oscillator power supply so as to be charged thereby to the output voltage (e.g., 345 volts) of the oscillator power supply. An electronic switch (e.g., an SCR) is connected to a junction between the charging capacitor and the oscillator power supply for, when actuated by an input pulse, completing a connection between the capacitor and the primary winding of the trigger transformer so that a high voltage trigger pulse is produced at the secondary winding of the trigger transformer.

Trigger circuit for Marx generators

A dual-energy x-ray system is provided which is useful in densitometry and other applications. A dual energy x-ray source, formed field emission x-ray tube driven by a Marx generator, produces a single x-ray pulse of a very short duration (e.g., 10 to 200 nanoseconds). The pulse provides x-ray energy of a first, high value early in the pulse and x-ray energy of a second, lower value later in the pulse so as to provide a dual energy level x-ray distribution comprising hard and soft x-rays. A detector system having dual x-ray energy discrimination properties, formed by soft and hard x-ray detectors and an inter-detector, receives the x-ray pulse and discriminates between the dual x-ray energy levels of the pulse.

Dual energy x-ray densitometry apparatus and method using single x-ray pulse

A portable X-ray unit, of a relatively light-weight, occoping a volume of less then one-half a cubic foot containing an x-ray head assembly, a unique Marx generator, a plurality of spark-gap switches and control electronics is disclosed. The Marx generator allows for the development of a relatively high voltage in excess of 100 kV, yet allows for the discharge thereof within the nanosecond range. The Marx generator is enclosed by an acrylic insulator that cooperates with an aluminum enclosure, which functions as a return current path for the capacitors in the Marx generator and also as a shield against the escape of electromagnetic radiation from the pulsed x-ray unit. The Marx generator and spark-gap switches are confined within the pressurized chamber that may contain nitrogen gas to reduce the separation of the gap in the spark-gap switches.

Mobile X-ray unit

A mobile X-ray machine includes an improved Marx generator. The capacitors sed in the Marx generator are disc capacitors each having opposed side surfaces having electrodes formed thereon and each including a insulative coating provided on the peripheral edge thereof. The capacitors are mounted in slots in a support structure and are supported by spring contact members located within the slots. The spring contact members include spring arms which engage the electrodes on the opposed side surfaces of the associated capacitor. The spring contact members also include support elements from which are suspended the spherical electrodes of spark-gap switches individually associated with each of the capacitors.

Capacitor mounting arrangement for marx generators

A field emission X-ray tube is provided for use in a mobile X-ray machine. n evacuated ceramic housing having a convoluted interior shape for dissipating sparks surrounds the components of the field emission tube. A cathode and, an anode which emits x-rays, are located within the ceramic housing. A hollow anode tube is connected to the anode at one end and a vacuum pinch off element at the other end. Stray radiation is attenuated by a lead ring positioned inside of the ceramic housing.

Growing community of inventors

Rockville, MD, United States of America

Glenn Emerson Holland