scholarly journals Experimental study on application characteristics of zeolite/water stuffing for the nanofluidic packer rubber

2020 ◽  
Vol 12 (11) ◽  
pp. 168781402097190
Author(s):  
Yihua Dou ◽  
Yafei Zhang ◽  
Jingwei Liang ◽  
Rui Chao
Keyword(s):  
Loading Rate ◽  
Throughput Capacity ◽  
Well Testing ◽  
Deformation Capacity ◽  
Pressure Threshold ◽  
System Temperature ◽  
Application Characteristics ◽  
Nanofluidic System ◽  
Sealing Failure ◽  
The Impact

Aiming at sealing failure problem of packer rubber during well testing and completion, a new type of “nanofluidic packer rubber” is developed. The nanofluidic packer rubber is composed of honeycomb matrix skeleton encapsulating nanofluidic system as stuffing. Taking ZSM-5 zeolite/water nanofluidic system as an example stuffing for the nanofluidic packer rubber, the application properties are studied by means of experiment. Ten loading/unloading cycles are carried out on the pretreated zeolite/water stuffing at different loading rates and system temperatures on a pressure-volume characteristic test bench. The impact law of loading rate and system temperature on repeatable practicability, pressure threshold, and deformation capacity of the stuffing are obtained and the influence mechanisms are discussed. Results show that the zeolite/water stuffing works stable and repeatable after the first three loading/unloading cycles. The loading rate has lifting effects on throughput capacity, pressure threshold and deformation capacity when system temperature is under 75°C. With the increase of system temperature, pressure threshold decrease, and throughput capacity and deformation capacity increase. All the application characteristics found in zeolite/water stuffing are favorable for improving the working performance of packer rubber. This work provides theoretical and data support for the application of the nanofluidic packer rubber.

scholarly journals Impact Loading During Distracted Running Before and After Auditory Gait Retraining

2018 ◽  
Vol 39 (14) ◽  
pp. 1075-1080 ◽  
Author(s):  
Eric Ching ◽  
Winko An ◽  
Ivan Au ◽  
Janet Zhang ◽  
Zoe Chan ◽  
...  
Keyword(s):  
Visual Feedback ◽  
Impact Loading ◽  
Auditory Feedback ◽  
Loading Rate ◽  
Real Life ◽  
Gait Retraining ◽  
Positive Acceleration ◽  
Before And After ◽  
The Impact ◽  
High Sound

AbstractVisual feedback gait retraining has been reported to successfully reduce impact loading in runners, even when the runners were distracted. However, auditory feedback is more feasible in real life application. Hence, this study compared the peak positive acceleration (PPA), vertical average (VALR) and instantaneous (VILR) loading rate during distracted running before and after a course of auditory feedback gait retraining in 16 runners. The runners were asked to land with softer footfalls with and without auditory feedback. Low or high sound pitch was generated according to the impact of particular footfall, when compared with the preset target. Runners then received a course of auditory gait retraining, and after the gait retraining, runners completed a reassessment. Runners before gait retraining exhibited lower PPA, VALR and VILR with augmented auditory feedback (p<0.049). We found a reduction in PPA, VALR and VILR after gait retraining, regardless of the presence of feedback (p<0.018). However, runners after gait retraining did not demonstrate further reduction in PPA and VALR with auditory feedback (p>0.104). A small effect of auditory feedback on VILR in runners after gait retraining was observed (p=0.032). Real time auditory feedback gait retraining is effective in impact loading reduction, even when the runners were distracted.

A 6-Week Transition to Maximal Running Shoes Does Not Change Running Biomechanics

2019 ◽  
Vol 47 (4) ◽  
pp. 968-973 ◽  
Author(s):  
J.J. Hannigan ◽  
Christine D. Pollard
Keyword(s):  
Ground Reaction Force ◽  
Loading Rate ◽  
Impact Force ◽  
Reaction Force ◽  
Vertical Ground Reaction Force ◽  
Risk Of Injury ◽  
Impact Peak ◽  
Running Shoes ◽  
Vertical Ground ◽  
The Impact

Background: A recent study suggested that maximal running shoes may increase the impact force and loading rate of the vertical ground-reaction force during running. It is currently unknown whether runners will adapt to decrease the impact force and loading rate over time. Purpose: To compare the vertical ground-reaction force and ankle kinematics between maximal and traditional shoes before and after a 6-week acclimation period to the maximal shoe. Study Design: Controlled laboratory study. Methods: Participants ran in a traditional running shoe and a maximal running shoe during 2 testing sessions 6 weeks apart. During each session, 3-dimensional kinematics and kinetics were collected during overground running. Variables of interest included the loading rate, impact peak, and active peak of the vertical ground-reaction force, as well as eversion and dorsiflexion kinematics. Two-way repeated measures analyses of variance compared data within participants. Results: No significant differences were observed in any biomechanical variable between time points. The loading rate and impact peak were higher in the maximal shoe. Runners were still everted at toe-off and landed with less dorsiflexion, on average, in the maximal shoe. Conclusion: Greater loading rates and impact forces were previously found in maximal running shoes, which may indicate an increased risk of injury. The eversion mechanics observed in the maximal shoes may also increase the risk of injury. A 6-week transition to maximal shoes did not significantly change any of these measures. Clinical Relevance: Maximal running shoes are becoming very popular and may be considered a treatment option for some injuries. The biomechanical results of this study do not support the use of maximal running shoes. However, the effect of these shoes on pain and injury rates is unknown.

The effect of mercury contaminants in major gas developments

2010 ◽  
Vol 50 (2) ◽  
pp. 740
Author(s):  
Malcolm Henderson ◽  
Kevin Hansen
Keyword(s):  
Environmental Safety ◽  
Gas Production ◽  
Concept Development ◽  
Lessons Learned ◽  
Operational Experience ◽  
Well Testing ◽  
Gas Streams ◽  
Development Phases ◽  
The Impact ◽  
Mercury Production

Over the past ten years the region has witnessed the unforeseen presence of mercury during gas production which has affected projects not only in southeast Asia but more recently in Australian waters. This has caused major operational challenges and has often involved costly production impairment, loss of condensate sales value and major brownfield modifications. Today–s awareness of mercury has seen a new vigilance in well testing programmes intended to address the identification of mercury in gas streams during the early appraisal and concept development phases of an asset lifecycle. This paper looks at the ways in which operating companies have resolved the issue of unforeseen mercury production to date, and the operational experience and lessons learned. The paper describes some of the fundamental testing programmes as well as the available technologies for treatment and removal of mercury from production and effluent streams. It also identifies the impact of mercury on the design and operation of specific parts of the process as well as the overall impact on facility topsides. The impact of mercury on a development is shown to be manageable and least costly where identified and addressed during the conceptual stage of a project development. Technical, environmental, safety and regulatory issues associated with mercury can be tackled, minimising risk of production deferment, and the costs incurred can be quantified and incorporated into economic models.

Heat Radiation Research and Optimized Analysis of Burner Boom on Semi-Submersible Drilling Platform

2018 ◽  
Author(s):  
Yuxin Xu ◽  
Guowei Sun ◽  
Songhua Liu ◽  
Fengguang Xue ◽  
Yong Bai
Keyword(s):  
High Speed ◽  
Oil And Gas ◽  
Heat Radiation ◽  
Well Testing ◽  
Wind Condition ◽  
Associated Gas ◽  
Testing Procedures ◽  
Water Curtain ◽  
Wind Influence ◽  
The Impact

Burner booms, one of the most important pieces of equipment for well testing procedures, are used to burn associated gas or oil-and-gas mixture. This paper first conducts a mesh sensitivity analysis to find a proper grid size. Grid independence is evaluated by the correlation value in different monitoring points. Then, the heat radiation of the burner boom on the semi-submersible drilling platform is analyzed using FDS. Without water curtain, it researches and compares the impact of low, medium and high speed wind condition on heat radiation. Without the wind influence, the simulation on heat radiation is done on the optimized water curtain design. The results show that the water curtain design can efficiently reduce the heat radiation on the platform, which has guiding significance for engineering design.

scholarly journals Impact of biomass burning emission on total peroxy nitrates: fire plume identification during the BORTAS campaign

2016 ◽  
Vol 9 (11) ◽  
pp. 5591-5606 ◽  
Author(s):  
Eleonora Aruffo ◽  
Fabio Biancofiore ◽  
Piero Di Carlo ◽  
Marcella Busilacchio ◽  
Marco Verdecchia ◽  
...  
Keyword(s):  
Biomass Burning ◽  
Atmospheric Pressure ◽  
Thermal Dissociation ◽  
Ann Model ◽  
Fire Plume ◽  
Pressure Threshold ◽  
Peroxy Nitrates ◽  
Artificial Neural Network Ann ◽  
The Impact

Abstract. Total peroxy nitrate ( ∑ PN) concentrations have been measured using a thermal dissociation laser-induced fluorescence (TD-LIF) instrument during the BORTAS campaign, which focused on the impact of boreal biomass burning (BB) emissions on air quality in the Northern Hemisphere. The strong correlation observed between the  ∑ PN concentrations and those of carbon monoxide (CO), a well-known pyrogenic tracer, suggests the possible use of the  ∑ PN concentrations as marker of the BB plumes. Two methods for the identification of BB plumes have been applied: (1)  ∑ PN concentrations higher than 6 times the standard deviation above the background and (2)  ∑ PN concentrations higher than the 99th percentile of the  ∑ PNs measured during a background flight (B625); then we compared the percentage of BB plume selected using these methods with the percentage evaluated, applying the approaches usually used in literature. Moreover, adding the pressure threshold ( ∼  750 hPa) as ancillary parameter to  ∑ PNs, hydrogen cyanide (HCN) and CO, the BB plume identification is improved. A recurrent artificial neural network (ANN) model was adapted to simulate the concentrations of  ∑ PNs and HCN, including nitrogen oxide (NO), acetonitrile (CH3CN), CO, ozone (O3) and atmospheric pressure as input parameters, to verify the specific role of these input data to better identify BB plumes.

scholarly journals Predicting Field Efficiency of Round-Baling Operations in High-Yielding Biomass Crops

2020 ◽  
Vol 2 (3) ◽  
pp. 447-457
Author(s):  
Robert “Bobby” Grisso ◽  
John S. Cundiff ◽  
Erin G. Webb
Keyword(s):  
Field Performance ◽  
Throughput Capacity ◽  
High Yield ◽  
Maximum Throughput ◽  
Potential Yield ◽  
Biomass Crops ◽  
Field Efficiency ◽  
Time Required ◽  
The Cost ◽  
The Impact

Model simulations for bioenergy harvest planning need to utilize equipment-capacity relationships for equipment operating under the high-yield conditions typical of a biomass crop. These performance assumptions have a direct bearing on the estimates of machine capacity, the number of machines required, and, therefore, the cost to fulfill the biorefinery plant demands for a given harvest window. Typically, two major issues in these models have been poorly understood: the available time required to complete the harvest operation (often called probability of workdays) and the capacity of the harvest equipment as impacted by yield. Simulations use annual yield estimates, which incorporate weather events, to demonstrate year-to-year effects. Some simulations also incorporate potential yield increases from genetically modified energy crops. There are limited field performance data for most current forage equipment used for harvesting high-yield biomass crops. Analysis shows that the impact of wrap/eject time for round balers resulted in a 50% reduction in achieved throughput capacity (Mg/h). After the maximum throughput is reached, the cost of the round bale operation (3.23 USD/Mg) is double that of the large-square baler (1.63 USD/Mg). The round baler achieved throughput capacity is 50% less (32.7 Mg/h compared to 71.0 Mg/h) than the large-square baler.

Experimental determination of impact tensile properties of adhesive butt joints with the split Hopkinson bar

2003 ◽  
Vol 38 (3) ◽  
pp. 233-245 ◽  
Author(s):  
T Yokoyama
Keyword(s):  
Tensile Strength ◽  
Layer Thickness ◽  
Energy Absorption ◽  
Loading Rate ◽  
Adhesive Layer ◽  
Hopkinson Bar ◽  
Butt Joints ◽  
Cyanoacrylate Adhesive ◽  
Split Hopkinson ◽  
The Impact

The tensile strength and energy absorption of adhesive butt joints at high rates of loading are determined with a tensile split Hopkinson bar using a cylindrical specimen. A commercially available single-component cyanoacrylate adhesive (instantaneous adhesive) and two different adherend materials are used in the adhesion tests. The impact tensile strength of the cyanoacrylate adhesive butt joints is determined from the applied tensile stress history at failure initiation. The impact absorbed energy is obtained by numerical integration of dynamic tensile load-adhesive deformation data. Comparative tension tests at low and intermediate rates of loading are performed on an Instron testing machine. An axisymmetric finite element analysis is carried out to investigate the stress distributions in the adhesive layer of the cyanoacrylate adhesive butt joints. The effects of loading rate, adherend material and adhesive layer thickness on the tensile strength and energy absorption of the cyanoacrylate adhesive butt joints are examined in detail. It is shown that the joint tensile strength increases significantly with increasing loading rate and is greatly affected by both the adhesive layer thickness and the adherend materials. The limitations of the technique are discussed.

Magnitude and Spatial Distribution of Impact Intensity Under the Foot Relates to Initial Foot Contact Pattern

2017 ◽  
Vol 33 (6) ◽  
pp. 431-436 ◽  
Author(s):  
Bastiaan Breine ◽  
Philippe Malcolm ◽  
Veerle Segers ◽  
Joeri Gerlo ◽  
Rud Derie ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Loading Rate ◽  
Ground Reaction Forces ◽  
Contact Pattern ◽  
Intensity Measure ◽  
Foot Kinematics ◽  
Contact Patterns ◽  
Reaction Forces ◽  
Local Impact ◽  
The Impact

In running, foot contact patterns (rear-, mid-, or forefoot contact) influence impact intensity and initial ankle and foot kinematics. The aim of the study was to compare impact intensity and its spatial distribution under the foot between different foot contact patterns. Forty-nine subjects ran at 3.2 m·s−1 over a level runway while ground reaction forces (GRF) and shoe-surface pressures were recorded and foot contact pattern was determined. A 4-zone footmask (forefoot, midfoot, medial and lateral rearfoot) assessed the spatial distribution of the vertical GRF under the foot. We calculated peak vertical instantaneous loading rate of the GRF (VILR) per foot zone as the impact intensity measure. Midfoot contact patterns were shown to have the lowest, and atypical rearfoot contact patterns the highest impact intensities, respectively. The greatest local impact intensity was mainly situated under the rear- and midfoot for the typical rearfoot contact patterns, under the midfoot for the atypical rearfoot contact patterns, and under the mid- and forefoot for the midfoot contact patterns. These findings indicate that different foot contact patterns could benefit from cushioning in different shoe zones.

Investigation on the Optimization of the Synthesis Processes of Morpholine from Residual Liquid of Morpholine Industry

2013 ◽  
Vol 726-731 ◽  
pp. 2917-2920
Author(s):  
Lei Wang ◽  
Peng Xiao
Keyword(s):  
Sodium Hydroxide ◽  
Efficient Method ◽  
Hydrolysis Reaction ◽  
Residual Liquid ◽  
Reaction Conditions ◽  
Waste Liquor ◽  
Yield Rate ◽  
System Temperature ◽  
The Impact

Aimed to reduce the impact on the environment about waste liquor of morpholine industry,and to increase the profit of it, in this paper, morpholine synthesis from industrial morpholine residual is discussed and optimized, by the method of pressurized hydrolysis reaction. The kinds and volume of catalyst and system temperature-pressure and other reaction conditions are analyzed and optimized to obtain the best yield rate of morpholine. Experiments suggest that pressurized hydrolysis reaction, using sodium hydroxide as catalyst, could be an efficient method to synthesize morpholine from industrial morpholine residual.

Accumulation of organic solids in gravel-bed constructed wetlands

1995 ◽  
Vol 32 (3) ◽  
pp. 229-239 ◽  
Author(s):  
Chris C. Tanner ◽  
James P. Sukias
Keyword(s):  
Organic Matter ◽  
Constructed Wetlands ◽  
Loading Rate ◽  
Dairy Farm ◽  
Effective Porosity ◽  
Water Losses ◽  
Gravel Bed ◽  
Tracer Dispersion ◽  
Conservative Tracer ◽  
The Impact

The effects of wastewater loading rate and planting with Schoenoplectus validus (soft-stem bulrush) on the accumulation of organic matter were investigated in four pairs of gravel-bed constructed wetlands. The planted and unplanted wetland pairs, each supplied with a different hydraulic loading of dairy farm wastewaters pre-treated in an anaerobic and aerobic lagoon, had received cumulative suspended solids loadings (∼ 82% volatile) of between ∼ 1.6 and 5.4 kg m−2 over a 22 month period. Vertical and horizontal gradients of organic matter accumulation were sampled by stratified coring, and the impact of solids accumulations on wastewater residence times investigated using bromide as a conservative tracer. Mean accumulations of organic matter in the unplanted wetlands ranged between 0.4 and 2.3 kg m−2, while those in the planted wetlands reached mean levels of nearly 4 kg m−2. Highest levels were recorded in influent zones (up to 9.5 kg m−2) and in the upper 100 mm of the substratum. The effective porosity of the highest loaded wetlands was markedly reduced compared to that in the lowest loaded wetlands, with mean retention times decreasing to around half of their theoretical values (corrected for evapotranspirational water losses). The planted wetlands retained higher apparent gravel porosity, despite greater accumulations of organic matter. High evapotranspiration rates during hot summer days, markedly extended retention times and increased tracer dispersion.

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