A pressure drop investigation of immiscible liquid-liquid micro flows

This paper was presented at the 2nd Micro and Nano Flows Conference (MNF2009), which was held at Brunel University, West London, UK. The conference was organised by Brunel University and supported by the Institution of Mechanical Engineers, IPEM, the Italian Union of Thermofluid dynamics, the Process Intensification Network, HEXAG - the Heat Exchange Action Group and the Institute of Mathematics and its Applications.Over the past decade there has been a considerable increase in the research on lab-on-a-chip applications that focuses on designing analytical chemical and biological devices. One such application is the possibility of integrating the functional steps of DNA analysis into a micro-total-analysis system (μTAS). Encapsulation of PCR samples within an inert carrier fluid allows the samples to be transported as micro-reactors. Plug based micro reactors suspended in an inert carrier fluid have a lot of promise in microfluidic analytical devices, offering a reduction in resident-time, reagents and labour with an increase in through-put, accuracy and quality. The development of a thin wetting film between the wall of the capillary and the micro reactor increase the interfacial area of the plug and can also intensify the internal circulation occurring within the plug. Only recently has work being preformed on the fluid mechanics that characterise this scale. An experimental study is carried out to study the effect capillary diameter, carrier viscosity and flow rate has on the pressure drop under bi-phasic flow conditions

Theory of Pseudomodes in Quantum Optical Processes

This paper deals with non-Markovian behaviour in atomic systems coupled to a structured reservoir of quantum EM field modes, with particular relevance to atoms interacting with the field in high Q cavities or photonic band gap materials. In cases such as the former, we show that the pseudo mode theory for single quantum reservoir excitations can be obtained by applying the Fano diagonalisation method to a system in which the atomic transitions are coupled to a discrete set of (cavity) quasimodes, which in turn are coupled to a continuum set of (external) quasimodes with slowly varying coupling constants and continuum mode density. Each pseudomode can be identified with a discrete quasimode, which gives structure to the actual reservoir of true modes via the expressions for the equivalent atom-true mode coupling constants. The quasimode theory enables cases of multiple excitation of the reservoir to now be treated via Markovian master equations for the atom-discrete quasimode system. Applications of the theory to one, two and many discrete quasimodes are made. For a simple photonic band gap model, where the reservoir structure is associated with the true mode density rather than the coupling constants, the single quantum excitation case appears to be equivalent to a case with two discrete quasimodes

Expression of a fungal ferulic acid esterase in suspension cultures of tall fescue (Festuca arundinacea) decreases cell wall feruloylation and increases rates of cell wall digestion

In the cell walls of grasses ferulic acid is esterified to arabinosyl residues in arabinoxylans that can then undergo oxidative coupling reactions to form ferulate dehydrodimers, trimers and oligomers which function to cross-link cell-wall polysaccharides, limiting cell wall degradability. Fungal ferulic acid esterase can release both esterified monomeric and dimeric ferulic acids from these cell wall arabinoxylans making the cell wall more susceptible to further enzymatic attack and increasing cell wall degradability. Non-embryogenic cell suspension cultures of Festuca arundinacea expressing a Aspergillus niger ferulic acid esterase (faeA) targeted to either the apoplast, or endoplasmic reticulum under the control of a constitutive actin promoter, or to the vacuole under the control of a soybean heat shock promoter, were established and FAE activity determined in the cells and medium during a growth cycle. Analysis of the ester-linked ferulates of the cell walls showed that all three transformed cell lines had both reduced ferulate levels and increased levels of xylanase mediated release of wall phenolics on autodigestion as well as increased rates of cell wall digestion in a simulated rumen environment, when compared to control non-transformed cells. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11240-017-1168-9) contains supplementary material, which is available to authorized users

Intensive Cultural Resources Survey of the Proposed Galveston County Project, Texas City, Galveston County, Texas

On behalf of Florida Gas Transmission Company, LLC (FGT), EDGE Engineering and Science, LLC (EDGE) has selected Horizon Environmental Services, Inc. (Horizon) to conduct a cultural resources survey and assessment for the proposed Galveston County Project. The project includes a proposed pipeline that will allow the delivery of natural gas to a new delivery point off the FGT mainline. The facilities to be installed include approximately 4.0 kilometers ([km] 2.5 miles) of 30.5-centimeter ([cm]12.0-inch) and 50.8-cm (20.0-inch) lateral piping as well as a measurement and regulation (M&R) station located at the southwest end of the new pipeline, referred to as the Attwater-Topaz M&R station. This portion of the proposed project is located approximately 2.9 km (1.8 miles) northwest of Texas City and crosses State Highway (SH) 146 in Galveston County, Texas. As part of the Galveston County Project, FGT will also be uprating a unit at their existing CS 4 compressor station in Matagorda County, Texas to maintain a sufficient delivery pressure to the proposed Attwater-Topaz M&R station. In accordance with Section 7(b) of the Natural Gas Act, the project requires Prior Notice authorization to the Federal Energy Regulatory Commission (FERC), which will serve as the lead federal agency for the undertaking. Because the undertaking is regulated by FERC, the undertaking falls under the regulations of Section 106 of the National Historic Preservation Act (NHPA) of 1966, as amended. The Antiquities Code of Texas (ACT) governs proposed undertakings by political subdivisions of the State of Texas and/or projects located on publicly owned lands. Approximately 11.3 hectares (27.8 acres) of the project area are owned by the Gulf Coast Water Authority (GCWA). Since the GCWA is a public entity, this portion of the project falls under the jurisdiction of the ACT. Survey of the GCWA property was carried out under Antiquities Permit No. 9449. Less than 0.1 hectare (0.2 acres) of additional temporary workspace (ATWS) falls within the State Highway (SH) 146 ROW, which is controlled by the Texas Department of Transportation (TxDOT). Since TxDOT is a State agency, survey of this area would also require an Antiquities Permit. However, this area has already been disturbed from road construction and underground utilities. Horizon therefore recommends no additional survey or shovel testing in this ATWS. Horizon sent a letter with this recommendation to the Texas Historical Commission (THC) on June 30, 2020. Originally, FGT did not define the actual limits of the proposed right-of-way (ROW) for the project. Rather, they elected to wait until after the environmental assessments on larger overall parcels were complete in order to select a route with the least amount of environmental impacts. As such, the cultural resources survey initially consisted of 100% survey of the entire 203.2 hectares (502.0 acres) that comprise the parcels traversed by the proposed pipeline. After FGT selected a proposed route, Horizon archeologists conducted additional fieldwork to ensure adequate survey coverage within the proposed ROW. From May 12 to 15, and June 17, 2020, Horizon archeologists Charles E. Bludau, Jr. and Luis Gonzales performed an intensive cultural resources survey of the project area to locate any cultural resources that would potentially be impacted by the proposed undertaking. Horizon’s archeologists traversed the project area on foot and thoroughly inspected the modern ground surface for aboriginal and historic-age cultural resources. The project area consists of an extensive, largely featureless coastal flat. An existing FGT pipeline corridor passes from northeast to southwest through the northern portion of the project area. In addition to pedestrian walkover, the recently revised 2020 Texas State Minimum Archeological Survey Standards (TSMASS) require at least 50 shovel tests for the first 10.1 hectares (25.0 acres) of a project plus at least one shovel test for every 2.0 hectares (5.0 acres) over the original 10.1 hectares (25.0 acres). This equates to a minimum of 145 shovel tests within the original 203.2-hectare (502.0-acre) project area. Horizon excavated156 shovel tests within this area, thereby exceeding the TSMASS for a project area of this size. The TSMASS require a minimum of 16 shovel tests per mile for projects measuring 30.0 m (98.4 feet) or less in width; this equates to a minimum of 40 shovel tests within the proposed ROW. Horizon exceeded this minimum by excavating 46 shovel tests within the proposed ROW. Shovel testing typically revealed shallow deposits of hydric, dark gray clay extending from the modern ground surface to depths ranging from 5.0 to 60.0 cm (2.0 to 23.6 inches) below surface, though most shovel tests were terminated at depths of 30.0 to 50.0 cm (11.8 to 19.7 inches) below surface. Shovel testing was capable of penetrating Holocene-age soils with the potential to contain subsurface archeological resources. No archeological sites or historic-aged structures were recorded within the project area during the survey. A modern cattle corral, constructed with modern lumber, is present in the northeast corner of the project area, south of Skyline Drive. The corral does not appear on any historical topographic maps. It is first visible in a 1981 aerial image, which indicates the corral is not of historic age. Based on the results of the survey-level investigations documented in this report, no significant cultural resources would be affected by the proposed undertaking. In accordance with 36 CFR 800.4, Horizon has made a reasonable and good faith effort to identify historic properties within the project area. No cultural resources were identified within the project area that meet the criteria for inclusion in the National Register of Historic Places (NRHP) under 36 CFR 60.4. Horizon recommends a finding of “no historic properties affected,” and no further archeological work is recommended in connection with the proposed undertaking. However, human burials, both prehistoric and historic, are protected under the Texas Health and Safety Code. In the event that any human remains or burial objects are inadvertently discovered at any point during construction, use, or ongoing maintenance in the project area, even in previously surveyed areas, all work should cease immediately in the vicinity of the inadvertent discovery, and the THC should be notified immediately

Manipulating the Phenolic Acid Content and Digestibility of Forage Grasses by Targeted Expression of Fungal Cell Wall Degrading Enzymes

Grass cell walls constitute 30-80% of forage dry matter, representing a major source of energy for ruminants. Ferulic acid (4-hydroxy-3-methoxy-cinnamic acid) and other hydroxycinnamic acids are ester linked to arabinosyl residues in arabinoxylans of grass cell walls and undergo oxidative coupling reactions resulting in the formation of a variety of dehydrodiferulate dimers which cross-link cell wall polymers. Although such cross-links have a number of important roles in the cell wall, they also hinder the rate and extent of cell wall degradation by ruminant microbial and fungal enzymes. We have shown previously the expression of a ferulic acid esterase gene from Aspergillus niger in Festuca arundinacea and the potential of the expressed FAE to break phenolic cross-links and release monomeric and dimeric ferulic acids on cell death in vacuole targeted FAE plants. This was enhanced several fold by the addition of exogenous recombinant xylanase (Buanafina et al., 2002). We propose to decrease the level of phenolic cross-linking of cell wall carbohydrate by inducible expression of FAE to the apoplast, ER and golgi and by co-expressing FAE and endo-ß-1,4-xylanase from Trichoderma reesei to the apoplast and vacuole

Shear stress fluctuations in the granular liquid and solid phases

We report on experimentally observed shear stress fluctuations in both granular solid and fluid states, showing that they are non-Gaussian at low shear rates, reflecting the predominance of correlated structures (force chains) in the solidlike phase, which also exhibit finite rigidity to shear. Peaks in the rigidity and the stress distribution's skewness indicate that a change to the force-bearing mechanism occurs at the transition to fluid behaviour, which, it is shown, can be predicted from the behaviour of the stress at lower shear rates. In the fluid state stress is Gaussian distributed, suggesting that the central limit theorem holds. The fibre bundle model with random load sharing effectively reproduces the stress distribution at the yield point and also exhibits the exponential stress distribution anticipated from extant work on stress propagation in granular materials.Comment: 11 pages, 3 figures, latex. Replacement adds journal reference and addresses referee comment