Liner Production Research Articles

Performance Calculation of Shaped Charges With Shear-Formed Liners

Production of shear-formed liners for rotating shaped charges is of interest since it causes the jet self-spinning effect, which drastically affects the penetration process. A novel four-part methodology for calculating the performance parameters of such charges is suggested. First, the liner strained state is related to the feed rate and mandrel angular velocity during the shear-forming process. Second, based on the polycrystal plasticity theory, a methodology for determining the liner's plastic anisotropy parameters depending on its strained state is realized. Third, a general dependence of the jet angular velocity on the liner plastic anisotropy parameters is obtained. The fourth part presents the methodology of shaped charge performance calculation with respect to spinning effects. The results of calculations performed according to the suggested methodology are in good agreement with experimental data. Calculations also show that the penetration depth increases 9% to 15% compared to a spinning shaped charge with a drawn liner (i.e., without the self-spinning effect) when the self-spinning jet rotates oppositely to the shaped charge. When they rotate in the same direction, penetration depth decreases critically (more than 50%).

Creep and Stress Relaxation Behavior of Two Soft Denture Liners

Numerous investigators stated the indications of soft denture lining materials; but no one determined the indications of these materials according to their chemical structure. The purpose of this investigation was to evaluate the viscoelastic properties of acrylic and silicon lining materials. This study investigated and compared viscoelastic properties of two resilient denture lining materials. Tested materials were laboratory processed; one of them was silicone-based liner product (Molloplast-B), and the other was plasticized acrylic resin (Vertex™ Soft). Twenty cylindrical specimens (10-20mm in length, 11.55mm in diameter) were fabricated in an aluminum mold from each material for creep and stress relaxation testing (the study of viscoelastic properties). Tests were performed by using the universal testing machine DY-34. Collected data were analyzed with t test statistics for statistically significant differences at the 95% confidence level. There was a clear difference in creep and stress relaxation behavior between acrylic and silicone liners. Statistical study of Young's moduli illustrated that Vertex™ Soft was softer than Molloplast-B. On the other hand, the results explained that the recovery of silicone material was better than of acrylic one. The creep test revealed that the plasticized acrylic resin lining material exhibited considerable creep, whereas silicone-based liner exhibited elastic behavior. Besides, the stress relaxation test showed that relaxation of the plasticized acrylic resin material was bigger than of the silicone-based liner.

Changes in geosynthetic clay liner (GCL) properties after 2 years in a cover over arsenic-rich tailings

A test cover comprised of three different needle-punched geosynthetic clay liner (GCL) products and covered with up to 1 m of cover soil (gravelly sand) was built over arsenic-rich tailings at a former gold mine in Nova Scotia, Canada, to evaluate the performance of the GCLs under local climatic conditions. Of the GCLs examined, one had untreated and two had polymer-enhanced natural sodium bentonite. The three GCLs each had different carriers: one with a woven geotextile, one with a scrim-reinforced nonwoven geotextile, and one with a woven geotextile laminated with a polypropylene film. At some locations, each type of GCL was placed in direct contact with the tailings. At other locations, each GCL was separated from the tailings by 0.15 m of cover soil. Samples of each GCL, tailings, and cover soil were recovered 1 and 2 years after construction. Tests show that the GCL with untreated bentonite maintained a low hydraulic conductivity (≤5 × 10−11 m/s) at locations where there was ≥0.7 m of cover soil above the GCL even though there was significant cation exchange of the sodium in the GCL with divalent cations in the tailings-soil porewater (the mole fraction of sodium (exchangeable sodium percentage (ESP)) decreased from 65% to 10%–17%). The GCL with polymer-enhanced bentonite had a lower hydraulic conductivity (≤3 × 10−11 m/s under ≥0.7 m of cover soil above the GCL) and experienced less cation exchange (ESP decreased to 19%–28%) than the standard GCL. The other GCL with polymer-enhanced bentonite and a carrier geotextile coated with a geofilm demonstrated the best hydraulic performance regardless of the thickness of cover soil or presence of an initially uncontaminated foundation layer. The presence of a foundation layer between the GCL and tailings impeded the migration of arsenic from the tailings into the GCLs. All GCLs were serving as an effective barrier to arsenic migration.

Running-in wear modeling of honed surface for combustion engine cylinderliners

The texture change during running-in alters the performance and efficiency of a tribo-mechanical system. During mass production of cylinder liners, a final finishing stage known as “plateau honing” is commonly added to reduce the running-in wear process of the liner surface. The majority of researchers think that this operation improves the engine efficiency and decreases oil consumption. It was believed that there are close links between the surface topography of honed cylinders change and their wear resistance during running-in. However, these interactions have not yet been established. Some running-in wear models were developed in the open literature to predict topographical surface changes without considering the running-in conditions.The present paper thus investigates the various aspects of the wear modeling that caused running-in problems in honed surfaces and its implications on ring-pack friction performance. To illustrate this, plateau honing experiments under different conditions were first carried out on an instrumented vertical honing machine. The plateau honing experiments characterize the surface modifications during running-in wear of cast-iron engine bores using advanced characterization method. Based on the experimental evidence, a running-in wear model was developed. Finally, a numerical extension of the developed model was applied to solve the Reynolds equation by taking into account the real surface topographies of the engine bore. This enables us to predict realistic friction performance within the cylinder ring-pack tribosystem.

The Process Rebuilding of Tire Liner Product Line System

According to characteristic process and control requirements of tire liner, the old process was rebuilded, combining with more precise and high efficiency control system, a new process method was designed. By practicality production, the system is stabilization, improving productivity and quality.

Comparison of tensile-bond strength of thin spray-on liners

One of the mechanical properties of thin spray-on liners, tensile-bond strength, is measured for comparison of thin spray-on liners. Test considerations, descriptions of apparatus, specimen preparation and test procedures are provided. The prepared thin spray-on liner mixture was poured onto a norite substrate using perspex mould with 35 mm cavities. A steel dolly was glued onto thin spray-on liner surface with a strong epoxy and then pulled in tension to measure the tensile-bond strength after curing periods ranging from 1 to 28 days. Testing was done under normal laboratory environmental conditions. The analysis of test results on 20 thin spray-on liner products, firstly, shows that tensile-bond strength increases remarkably for most thin spray-on liners with increasing curing time. Secondly, the categorisation and comparison of thin spray-on liners are possibly based on the tensile-bond strength.

Erratum to: Transport properties of natural gas through polyethylene nanocomposites at high temperature and pressure

High density polyethylene (HDPE)/clay nanocomposites containing nanoclay concentrations of 1, 2.5, and 5 wt% were prepared by a melt blending process. The effects of various types of nanoclays and their concentrations on permeability, solubility, and diffusivity of natural gas in the nanocomposites were investigated. The results were compared with HDPE typically used in the production of liners for the petroleum industry. Four different nanoclays—Cloisite 10A, 15A, 30B and Nanomer 1.44P—were studied in the presence of CH4 and a CO2/CH4 mixture in the temperature range 30–70 °C and pressure range 50–100 bar. The permeability and diffusivity of the gases were considerably reduced by the incorporation of nanoclay into the polymer matrix. Addition of 5 wt% loading of Nanomer 1.44P reduced the permeability by 46% and the diffusion coefficient by 43%. Increasing the pressure from 50 to 100 bar at constant temperature had little influence on the permeability, whereas increasing the temperature from 30 to 70 °C significantly increased the permeability of the gas. Additionally, the effect of crystallinity on permeability, solubility, and diffusivity was investigated. Thus, the permeability of the CO2/CH4 mixture in Nanomer 1.44P nanocomposite was reduced by 47% and diffusion coefficient by 35% at 5 wt% loading, 50 °C, and 100 bar, compared with pure HDPE.

Anisotropic light propagation in paper

Abstract We investigate anisotropic light propagation in paper using both a theoretical model and experiments. The theoretical model utilizes the Monte Carlo method to solve the photon transport equation numerically. It is assumed that wood fibres are represented by infinitely long, homogeneous and straight cylinders. The layer-like microstructure and anisotropic orientation of the fibres is considered in the model. The conical scattering by cylindrical objects, the wood fibres, is argued as the main source of anisotropic scattering. Simulations revealed that laterally resolved transmittance exhibits directional dependence. Experiments on light transmitted through a standard kraft liner product confirmed that light in fact do propagate more in the machine direction than in the cross direction. Reasonably good agreement was obtained between experimentally and numerically obtained iso-intensity patterns.

Performance Evaluation of a Newly Developed Variable-Rate Sprayer for Nursery Liner Applications

An experimental variable-rate sprayer designed for liner applications was tested by comparing its spray deposit, coverage, and droplet density inside canopies of six nursery liner varieties with constant-rate applications. Spray samplers, including water-sensitive papers (WSP) and nylon screens, were mounted inside tree canopies to collect spray deposit and coverage from variable-rate and constant-rate (555 and 1,110 L ha-1) applications. Models for estimating spray volume savings of the variable-rate sprayer compared to constant-rate and tree-row-volume (TRV) rate applications were developed for various liner canopy sizes and tree spacings. The accuracy of the model was validated with the field test data. For the liner trees tested, the variable-rate sprayer delivered 151 to 359 L ha-1 application rates, while the conventional constant-rate application required 1,110 L ha-1. Due to substantially lower spray output, the variable-rate application had lower (but sufficient) spray deposit, coverage, and droplet density than the constant-rate applications. The variable-rate application also had significantly less variations in spray deposit within canopies of different-size trees. Test results showed that the variable-rate sprayer reduced spray volume by up to 86.4% and 70.8% compared to the 1,110 L ha-1 and TRV-based rate applications, respectively, while the model-estimated savings were up to 94.6% for the 1,110 L ha-1 application and 57.7% for the TRV-based rate applications. Therefore, the newly developed variable-rate sprayer would bring great reductions in pesticide use and safeguard the environment for nursery liner production.

GROWTH ACCELERATION AND INCREASED OUT PLANT SURVIVAL OF ONTARIO AND OHIO GROWN TREE LINERS

A production system developed at Ohio State University (OSU), Columbus, OH, using retractable roof greenhouses (RRGs) (Cravo Equipment, Ltd., Brantford, ON, Canada) and containerized tree liner production has indicated acceleration of production times when out planted to Pot-in-Pot (PIP) or nursery fields versus conventional bareroot (BR) or polyhouse production. The system also increased cropping consistency via reduced mortalities and showed promise in new market expansion, including higher priced, difficult-to-grow species. In 2004, #3 (trade 3-gallon or 11.4 L) containerized tree liners from RRGs had 0% mortality versus field BR production Quercus rubra at 42% after out-planting into nursery fields to grow on as specimen trees. Averaged over species, RRG liners reached saleable size of 50 mm caliper two years sooner than the BR liners (a 40% reduction in production time). In 2006, #3 containerized tree liners from RRG's had 27% mortality versus field BR production at 87% after out-planting to #7 (trade 7-gallon or 26.5 L) containers and harsh conditions in PIP fields. Averaged over species and one growing season, caliper and height of RRG liners were 82 and 84% larger than BR liners, respectively. Recently RRG liners have shown utility in high stress environments along Ontario, Canada highways leading The Ontario Ministry of Transportation to research an optimized planting process including use of RRG's liners.

Estimated Nursery Liner Production Costs for Woody Ornamental Plant Stock

Ornamental plant growers must be able to accurately assess production costs associated with woody liner stock to gain profit potential in a highly competitive industry. Fixed and variable cost inputs may not be intuitive or readily apparent to growers and may even differ between common types of production in the trade. To help liner producers identify profit-based price points for their woody ornamental liner stock, we modeled costs associated with producing familiar species and cultivars of a representative deciduous shade tree, a broadleaf evergreen, and a needle leaf evergreen liner. Production costs are projected down to individual plant units for each of the three most common liner production systems, including a field ground bed system, a polyhouse-covered (plant protection structure sheathed with one layer of 6-mil polyethylene film) ground bed system, and a polyhouse-covered container system. Production costs for individual plants varied due to the actual growing space available within each system. The field ground bed system offered greatest flexibility in crop planting density, with cost potentially distributed among the largest number of salable units. In addition to modeled costs, advantages and disadvantages of each liner cropping system are discussed.

Multiscale study of finish-honing process in mass production of cylinder liner

Abstract In mass production of cylinder liners, the industrial honing involves multistage abrasive finishing processes, using at first a coarse abrasive stones, and then progressively finer grades, so that a very structured surface of liner is produced. A useful method in diagnosis of industrial honing is presented. It is based on the use of multiscale surface analysis to study the progress of abrasive wear mechanisms which occurred in honing while it was in operation. Thus, the examination of generated surface components by honing to detect the topographical signatures, and especially, signatures of surface in the right scale, is an important part of quality assessment in cylinder liner production.

Assessments of Bare-root Liner Quality and Purchasing Decisions Made by Green Industry Professionals

Production of high-quality nursery liners has long been a foundation principle for enabling success and business longevity in the competitive nursery industry. Unfortunately, many different characteristics can be used to define liner “quality,” ranging from physiological parameters measurable in scientific studies field establishment success and transplant production performance to gut-level hunches on the part of growers. A more complete understanding of what buyers are looking for in a bare-root liner would significantly enhance the success of producers in meeting the demands of end-users. As a result, a choice study involving a point-of-purchase simulation was designed to assess preferences of green industry professionals when viewing bare-root 1 + 0 nursery liners. A conjoint design was used for this study and involved six key attributes of liners: 1) number of first-order lateral roots (FOLR); 2) price; 3) production region; and uniformities of 4) height; 5) canopy density; and 6) liner caliper. A visual survey based on a large, color graphic depicting six distinct bare-root 1 + 0 liners with different combinations of attributes was administered together with a demographic questionnaire at four different green industry tradeshows and extension grower education and outreach venues in the southeastern United States. Results from 248 completed surveys corroborated previously reported results suggesting that high FOLR is the most important attribute influencing preference for 1 + 0 liner products followed by uniform liner height and canopy density. Contrary to a priori expectations, neither price nor region of production substantially influenced product preference. Utility values were calculated for each attribute level using outputs from the experimental model. These values can be used by growers to adjust production methods to improve liners with attributes that end-users value most. In addition, growers will be able to better estimate product ratings, redirect marketing efforts, and assess sales potential for various bare-root 1 + 0 liner products in U.S. markets.

Bare Root Liner Production Can Alter Tree Root Architecture

Abstract Typical nursery production practices, such as root pruning and transplanting, can alter tree root architecture and contribute to root systems that are too deep. In a study of field-grown liner production, root architecture was examined at each stage of the production process, from first year seedlings or rooted cuttings, through 4 to 5 year old branched liners. Depth and diameter of structural roots were recorded on ten replications each of Acer saccharum, Gleditsia triancanthos, Pyrus calleryana, and apple seedling rootstocks; Platanus ‘Columbia’ clonal rooted cuttings; and apple EMLA 111 clonal rootstock produced by mound propagation. By the time the liners reached marketable size, most natural lateral roots emerging from the primary root were lost. Simultaneously, adventitious roots were produced deeper on the root shank at the pruned end of the primary root. These changes in architecture result in the formation of an ‘adventitious root flare’ that is deeper in the soil than a natural root flare. The depth of this new root flare is dependent upon nursery production practices and may influence the ultimate depth of structural roots in the landscape.

遷移金属触媒による不斉アリル位置換反応の新展開

Asymmetric allylic substitution catalyzed by an organometallic complex is a powerful method to create carbon-carbon and carbon-heteroatom bonds with high enantioselectivity, and is often applied to total syntheses of biologically active organic molecules. The reaction via a symmetrically substituted π-allylpalladium intermediate has been widely studied using a variety of chiral ligands. However, the reaction of unsymmetrically substituted allylic compounds is still a challenging research subject, because nucleophilic attack generally takes place at the less hindered allylic carbon giving a liner product in the reaction of monosubstituted allylic substrate with palladium catalysts. Recently, other transition metal complexes have shown high potential in this type of reactions, in which a branched isomer is obtained as a main product by the substitution at the hindered allylic carbon. This review focuses on the recent progress in the asymmetric allylic substitutions of unsymmetrically substituted allylic compounds producing branched products with high regio- and enantioselectivities.

Nitrogen and Substrate Assessment For Pot-in-Pot Production in the Intermountain West

Abstract We investigated optimum nitrogen rates and different growth substrates for short-term finish production of container and bare root shade tree liners in a pot-in-pot production system in the Intermountain West. In one study, nitrogen ranging from 0–27 g N-tree−1 (0–36 lbs N·1000 ft−2) as urea was applied to quaking aspen (Populus tremuloides), ‘Autumn Blaze’ maple (Acer × freemannii ‘Autumn Blaze’), ‘Chanticleer’ flowering pear (Pyrus calleryana ‘Chanticleer’), and ‘Canada Red’ chokecherry (Prunus virginiana ‘Canada Red’). Twenty-six liter liners (#7 container) were transplanted into 57 liter (#15) containers in a retail nursery finishing pot-in-pot system. Trunk diameter growth and shoot-tip elongation measurements were recorded for one growing season. Overall, only pear had a consistent increase in terminal shoot and trunk growth in response to N at 9 g N·tree−1 (12 lbs N·1000 ft−2). Maple and chokecherry exhibited modest lateral shoot growth at 4.5 and 18 g N·tree−1 (10–24 lbs N·1000 ft−2), and aspen growth had no response to N. The second study evaluated the effect of nitrogen rates and substrate type on first-year trunk diameter growth of bare root common chokecherry (Prunus virginiana) and Aristocrat flowering pear (Pyrus calleryana ‘Aristocrat’). Large bare-root liners were installed into a finishing pot-in-pot system with three substrate treatments, a proprietary, a commercial mix using several organic matter sources, and a simple composted bark-pumice mix. Five nitrogen rates, 0–9 g N·tree−1, (0–12 lbs N·1000 ft−2) were applied to each substrate. Pear again had a modest increase in trunk growth at 2.2 g N per tree, but had no response to the different growth substrates. Chokecherry trunk growth did not increase with nitrogen nor did substrate treatment substantively affect growth. This study indicates that Intermountain West retail nurseries can likely reduce first-year nitrogen applications to container and bare root liner stock during finish production, and use a simpler media to achieve optimum growth at potentially lower cost.

Alternative descriptions of roughness for cylinder liner production

The roughness of stratified surfaces such as cylinder liners, produced by plateau honing, is functionally important in their tribology but is notoriously difficult to characterise. An issue in manufacturing quality control related to their tribological function is the comparative ability of various roughness characterisation systems. In this paper the Rk family of parameters is compared with the Rq family as regards stability and discrimination. When coefficients of variation of the two parameter families are compared as a measure of stability, CVs of individual parameters vary between 8% and 20% but do not seem to indicate a clear advantage to either family. When the correlation of parameters within and between the two groups is computed as a measure of relative discriminative ability, many parameters are found to be highly correlated, to the point where values of Rpk and Rpq are effectively indistinguishable. The relative robustness of the parameters is also established by simulation of surface or measurement artefacts: outlying peaks and valleys, high-frequency noise, changes in stylus or skid radius, changes in high-pass filter and in assessment length. Outlying peaks cause a large increase in Rpk, while outlying valleys have little effect. The Rq parameters are more sensitive to high-frequency noise than the Rk parameters. Increasing the stylus radius reduced the valley parameters, while adding a 25 mm radius skid increased Rk and Rpq by as much as 15%. Increasing the short-wavelength cut-off from 2.5 μm to 8 μm reduced most parameters, particularly the peak parameters, while replacing the robust Gaussian filter used throughout by a valley-suppression filter had little effect. Finally reducing the assessment length from 17 mm to 4 mm decreased the values of many parameters by up to 11%. Increasing plateau honing time decreased plateau roughness, while increasing pressure during coarse honing increased valley roughness, but these changes could not be correlated with roughness parameters. This suggests that the optimum parameter set has not yet been found.

Quantification of annular flow in lined pipelines

This paper attempts to quantify the amount of flow within the annular space that could exist between a polymeric liner and a deteriorated host pipe. Inadequate fit of the liner within sewer line segments is likely to cause annular flow that will result in a higher flow rate within the wastewater collection system. The results of full-scale field tests performed by the authors on 12 pipelines lined with four different deformed/reformed or fold-and-form (DR/FF) and cured-in-place-pipe (CIPP) liner products indicated that gaps of different sizes existed in all of the tested pipelines. These gaps have resulted in variable annular flow in the tested pipelines. Based on the results of the full-scale tests, a mathematical relationship was established between the annular flow in a lined pipeline and the annular space. The relationship between the annular flow rate and the average annular gap size depends on the difference in head between the entry and exit points along the pipeline. In turn, the average annular gap size depends on many factors including tolerances and imperfections in the host pipe and liner, conditions of the host pipe and the quality of liner installation. A third-order polynomial equation was found to best describe the relationship between the annular flow and average gap size under high differential heads (up to 3.0 m or 10 ft); whereas, a logarithmic relationship fits best under low differential heads for wider range of annular gap sizes (up to 17.8 mm or 0.70 in.). Based on the results of the full-scale tests, this is believed to be more representative of typical liner installations.

Liner Production of Florida Native Wildflowers by Seed

ENH-1087, a 4-page illustrated fact sheet by Jeffrey G. Norcini and James H. Aldrich, describes in detail the methods that the authors have successfully used to produce liners of Florida native wildflowers under greenhouse conditions. Includes references. Published by the UF Department of Environmental Horticulture, December 2007. ENH1087/EP342: Liner Production of Florida Native Wildflowers by Seed (ufl.edu)

(39) Determination of the Optimum Species for Ohio Tree Liner Production in Retractable Roof Greenhouses

Many Ohio growers import liners from the West Coast due to the increased growing season on the West Coast. Lengthening the season in Ohio may provide a way for Ohio growers to produce liners of their own. Retractable roof greenhouses (RRG) are one possible way to extend the growing season in Ohio. Research done previously at The Ohio State University suggests that retractable roof greenhouses do in fact lengthen the growing season, and tree liners can be produced using RRG. The objectives of this study were: 1) to determine the optimal growing environment from three different environments; and 2) to determine the optimal species for tree liner production in Ohio. In Oct. 2004, 180 liners each of Cladrastis kentuckea, Quercus rubra, Stewartia pseudocamellia, Syringa reticulata, and Tilia cordata were upshifted to 3-gallon pots. In Mar. 2005, 90 of each species were transferred to either a flat roof retractable house (FRRG), peak roof retractable house (PRRG), or polyhouse. Growth was measured in Mar. (initial), June, Aug., and Oct. 2005 by taking leaf area, shoot and root dry weights, height, and caliper. There were no differences across species and dates between the environments for any of the parameters measured. Tilia showed the greatest increase in growth from June to October in all the parameters measured except leaf area. Cladrastis showed the greatest increase in leaf area from June to October. There were species by date interactions. Quercus had the greatest root weight in October. Syringa and Quercus were not significantly different from each other and had the highest shoot weights and leaf areas in October. Tilia, Quercus, and Syringa had the highest calipers in October.