Miniature high pressure needle valve

ABSTRACT Previous results demonstrated that hepatitis A virus (HAV) could be inactivated by high hydrostatic pressure (HHP) (D. H. Kingsley, D. Hoover, E. Papafragkou, and G. P. Richards, J. Food Prot. 65:1605-1609, 2002); however, direct evaluation of HAV inactivation within contaminated oysters was not performed. In this study, we report confirmation that HAV within contaminated shellfish is inactivated by HHP. Shellfish were initially contaminated with HAV by using a flowthrough system. PFU reductions of >1, >2, and >3 log10 were observed for 1-min treatments at 350, 375, and 400 megapascals, respectively, within a temperature range of 8.7 to 10.3Ã¯Â¿Â½C. Bioconcentration of nearly 6 log10 PFU of HAV per oyster was achieved under simulated natural conditions. These results suggest that HHP treatment of raw shellfish will be a viable strategy for the reduction of infectious HAV.

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Graphitization of diamond at zero pressure and at a high pressure

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1972.0086 ◽

1972 ◽

Vol 328 (1574) ◽

pp. 413-427 ◽

Cited By ~ 101

Keyword(s):

High Pressure ◽

Activation Volume ◽

Activation Energies ◽

Single Atom ◽

Diamond Surface ◽

Temperature Range ◽

Natural Diamonds ◽

Rate Controlling Step

Natural diamonds have been heated in the temperature range of 1850 to 2000 °C at zero pressure and the rates at which diamond transforms to graphite measured. For {111} and {110} surfaces activation energies of 253+18 and 174+12 kcal mol -1 (1159 + 75 and 728 + 50 kJ/mol) respectively have been obtained. Diamonds have also been heated in the temperature range of 1950 to 2200 °C under a pressure of 48 + 3 kbar (4.8 + 0.3 GPa) and an activation volume of about 10 cm 3 mol -1 obtained for both {111} and {110} surfaces. It is proposed that the rate controlling process in the graphitization of diamond is the detachment of a single atom from the diamond surface. This is contrary to previous proposals in which the detachment of groups of atoms have been considered to be the rate-controlling process. In the present work, it is suggested that the rate-controlling step for graphitization is the detachment of a triply bonded atom from a {111} surface and of a doubly bonded atom from a {110} surface.

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Homogenizing valve design and its influence on milk fat globule dispersion: I. Low rate of flow (100 1 h–1, Re ≤ 3000)

Journal of Dairy Research ◽

10.1017/s0022029900022408 ◽

1982 ◽

Vol 49 (2) ◽

pp. 309-315 ◽

Cited By ~ 6

Author(s):

Leslie W. Phipps

Keyword(s):

High Pressure ◽

Milk Fat ◽

Disruptive Effect ◽

Valve Design ◽

Milk Fat Globule ◽

Fat Globule ◽

Small Capacity ◽

Low Rate

SummaryThe efficiencies of small capacity homogenizing valves of the high pressure type have been studied in relation to their design. The performance of a valve was strongly affected by the magnitude of the effective inlet diameter D0 of the seating for a given exit diameter D when D0/D > 0·5. The indications are that narrow mating faces situated such that D0/D → 1 should maximize performance. Milk fat globule dispersion varied regularly with a valve's face angle; optimum angles for maximum disruptive effect were about +35° and –30°. Perforated metal insets interposed between flat faces of a valve piece and its seat noticeably improved fat dispersion; reductions in mean globule diameter of up to 25% were obtained.Variations in the sensitivity of different milks to homogenization were observed but avoided by appropriate experimental procedures.

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Evolution of Generic Vanelets Applied to a High Pressure Compressor

Volume 6A: Turbomachinery ◽

10.1115/gt2013-95561 ◽

2013 ◽

Author(s):

Andreas Loos ◽

Tobias Mayenberger ◽

Florian Danner ◽

Hans-Peter Kau

Keyword(s):

High Pressure ◽

Stokes Equations ◽

Main Flow ◽

Navier Stokes ◽

Stable Operation ◽

Navier Stokes Equations ◽

Surge Margin ◽

Flow Phenomena ◽

Negative Effect ◽

Generic Design

The flow field of high pressure compressors is strongly influenced by secondary flow phenomena which lead to performance degradations. A significant fraction of the associated losses arises from tip as well as hub clearance vortices and their interaction with the main flow. In order to decrease the negative effect of clearance vortices, the application of vanelets, winglet-like structures attached to the tips of a cantilevered stator, is studied within the present paper. Different vanelets of generic design are applied to the stator and evaluated with respect to their aerodynamic effect by comparison against a datum configuration. The model comprises the investigated stator enclosed between two rotating blade rows. Detailed insight into the underlying phenomena is provided by numerical investigations with the compressible Reynolds-averaged Navier-Stokes equations. The structures led to an increased efficiency at the aerodynamic design point due to the suppression of the clearance mass flow in combination with a reduced vortex cross section. Under strongly throttled conditions a so called vanelet corner stall developed, which induced blockage near hub. Thus the main flow was displaced towards casing enhancing stable operation of the downstream rotor. Surge margin was consequently increased.

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Microstructure and Phase Transformation of Super-High Pressure Mg-Li Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.816.375 ◽

2015 ◽

Vol 816 ◽

pp. 375-380 ◽

Cited By ~ 1

Author(s):

Qiu Ming Peng ◽

Hui Fu ◽

Yan An Wang ◽

Hui Li

Keyword(s):

High Pressure ◽

Phase Transformation ◽

Heat Treating ◽

Dendritic Morphology ◽

Metallic Materials ◽

Cast Sample ◽

Temperature Range ◽

Electronic Distribution ◽

Heat Treated ◽

Dislocation Movement

Super-high pressure (SHP) changes crystal structure and electronic distribution of metallic materials, which plays an important role in properties. Herein, a duplex Mg-7%wt.Li alloy was heat-treated under SHP (2 GPa) by cubic-anvil large-volume press with six rams for 2 h in the temperature range of 450~1350 °C. Microstructure, phase transformation behavior and mechanical properties were examined. Compared with the as-cast sample, the SHP samples after heat-treating from 450 °C to 750 °C under 2 GPa were composed of twinning in addition to duplex structure. Comparatively, the samples treated between 1050 °C and 1350 °C exhibit typical dendritic morphology. Phase transformation from Li3Mg7 phase or Li0.92Mg4.08 phase to Li3Mg17 phase occurred during the whole investigated temperature range, in which only the Li3Mg17 phase maintained when the temperature exceeds 1050 °C. The microhardness of the sample prepared at 750 °C under 2 GPa was 73.15HV, which is 1.5 times higher than that of the as-cast one. The improved microhardness is mainly attributed to the formation of nanosized twins during SHP treatment. These fine twins effectively prohibit the dislocation movement during deformation. It reveals the SHP is an effective approach to prepare high performation Mg alloys.

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Silicon Carbide Integrated Circuits With Stable Operation Over a Wide Temperature Range

IEEE Electron Device Letters ◽

10.1109/led.2014.2362815 ◽

2014 ◽

Vol 35 (12) ◽

pp. 1206-1208 ◽

Cited By ~ 20

Author(s):

Reza Ghandi ◽

Cheng-Po Chen ◽

Liang Yin ◽

Xingguang Zhu ◽

Liangchun Yu ◽

...

Keyword(s):

Silicon Carbide ◽

Integrated Circuits ◽

Wide Temperature Range ◽

Stable Operation ◽

Temperature Range

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Nano-Scale Silicon Quantum Dot-Based Single-Electron Transistors and Their Application to Design of Analog-to-Digital Convertors at Room Temperature

Journal of Circuits System and Computers ◽

10.1142/s0218126617502012 ◽

2017 ◽

Vol 26 (12) ◽

pp. 1750201

Author(s):

Hamed Aminzadeh ◽

Mohammad Ali Dashti ◽

Mohammad Miralaei

Keyword(s):

Quantum Dot ◽

Coulomb Blockade ◽

Room Temperature ◽

Symmetric Functions ◽

Single Electron ◽

Stable Operation ◽

Single Electron Transistors ◽

Analog To Digital ◽

Temperature Range ◽

Electron Transistors

Room-temperature analog-to-digital converters (ADCs) based on nanoscale silicon (Si) quantum dot (QD)-based single-electron transistors (SETs) can be very attractive for high-speed processors embedded in future generation nanosystems. This paper focuses on the design and modeling of advanced single-electron converters suited for operation at room temperature. In contrast to conventional SETs with metallic QD, the use of sub-10-nm Si QD results in stable operation at room temperature, as the observable Coulomb blockade regime covers effectively the higher temperature range. Si QD-based SETs are also fully compatible with advanced CMOS technology and they can be manufactured using routine nanofabrication steps. At first, we present the principles of operation of Si SETs used for room-temperature operation. Possible flash-type ADC architectures are then investigated and the design considerations of possible Coulomb oscillation regimes are addressed. A modified design procedure is then introduced for [Formula: see text]-bit SET-based ADCs, and validated through simulation of a 3-bit ADC with a sampling frequency of 5 GS/s. The ADC core is comprised from a capacitive signal divider followed by three periodic symmetric functions (PSFs). Simulation results demonstrate the stability of output signals at the room-temperature range.

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