Hot mill process parameters impacting on hot mill tertiary scale formation

NASA Astrophysics Data System (ADS)

Kennedy, Jonathan Ian

For high end steel applications surface quality is paramount to deliver a suitable product. A major cause of surface quality issues is from the formation of tertiary scale. The scale formation depends on numerous factors such as thermo-mechanical processing routes, chemical composition, thickness and rolls used. This thesis utilises a collection of data mining techniques to better understand the influence of Hot Mill process parameters on scale formation at Port Talbot Hot Strip Mill in South Wales. The dataset to which these data mining techniques were applied was carefully chosen to reduce process variation. There are several main factors that were considered to minimise this variability including time period, grade and gauge investigated. The following data mining techniques were chosen to investigate this dataset: Partial Least Squares (PLS); Logit Analysis; Principle Component Analysis (PCA); Multinomial Logistical Regression (MLR); Adaptive Neuro Inference Fuzzy Systems (ANFIS). The analysis indicated that the most significant variable for scale formation is the temperature entering the finishing mill. If the temperature is controlled on entering the finishing mill scale will not be formed. Values greater than 1070 °C for the average Roughing Mill and above 1050 °C for the average Crop Shear temperature are considered high, with values greater than this increasing the chance of scale formation. As the temperature increases more scale suppression measures are required to limit scale formation, with high temperatures more likely to generate a greater amount of scale even with fully functional scale suppression systems in place. Chemistry is also a significant factor in scale formation, with Phosphorus being the most significant of the chemistry variables. It is recommended that the chemistry specification for Phosphorus be limited to a maximum value of 0.015 % rather than 0.020 % to limit scale formation. Slabs with higher values should be treated with particular care when being processed through the Hot Mill to limit scale formation.

Study on Online Analysis of Transfer Function of Variable-Speed Rolling Mill Motor with Shaft Torsional Vibration Systems

NASA Astrophysics Data System (ADS)

Tamaoki, Toshifumi; Takanezawa, Makoto; Kimoto, Masanori; Morita, Noboru; Hoshino, Takeo; Hashizume, Kenji

The torsional vibration between metal rolling rolls and a rolling mill motor, may occur in recent days, as a result of higher speed response adjustment for variable speed rolling mill motor drive system. Issues in this paper are focused on excess acceleration value, in tangential direction of the mill motor rotor, which is caused by the motor shaft torsional resonance at the white noise signal superposition to the speed reference signal of the motor drive system for the online transfer function analysis. As a result of the acceleration analysis, the acceleration values in “G” (Relative acceleration value on the basis of Gravity) can be plotted on “Bode-Diagram”, which is namely frequency response for the speed signal amplitude transmission ratio. In addition, relation between the white noise amplitude reduction and the transfer function analysis accuracy deterioration is also examined, in this paper. As the amplitude of the white noise decreases, the analysis error increases because of the reduction in the resolution when the amplitude of the white noise signal is small.

Optimal Cluster Mill Pass Scheduling With an Accurate and Rapid New Strip Crown Model

NASA Astrophysics Data System (ADS)

Malik, Arif S.; Grandhi, Ramana V.; Zipf, Mark E.

2007-05-01

Besides the requirement to roll coiled sheet at high levels of productivity, the optimal pass scheduling of cluster-type reversing cold mills presents the added challenge of assigning mill parameters that facilitate the best possible strip flatness. The pressures of intense global competition, and the requirements for increasingly thinner, higher quality specialty sheet products that are more difficult to roll, continue to force metal producers to commission innovative flatness-control technologies. This means that during the on-line computerized set-up of rolling mills, the mathematical model should not only determine the minimum total number of passes and maximum rolling speed, it should simultaneously optimize the pass-schedule so that desired flatness is assured, either by manual or automated means. In many cases today, however, on-line prediction of strip crown and corresponding flatness for the complex cluster-type rolling mills is typically addressed either by trial and error, by approximate deflection models for equivalent vertical roll-stacks, or by non-physical pattern recognition style models. The abundance of the aforementioned methods is largely due to the complexity of cluster-type mill configurations and the lack of deflection models with sufficient accuracy and speed for on-line use. Without adequate assignment of the pass-schedule set-up parameters, it may be difficult or impossible to achieve the required strip flatness. In this paper, we demonstrate optimization of cluster mill pass-schedules using a new accurate and rapid strip crown model. This pass-schedule optimization includes computations of the predicted strip thickness profile to validate mathematical constraints. In contrast to many of the existing methods for on-line prediction of strip crown and flatness on cluster mills, the demonstrated method requires minimal prior tuning and no extensive training with collected mill data. To rapidly and accurately solve the multi-contact problem and predict the strip crown, a new customized semi-analytical modeling technique that couples the Finite Element Method (FEM) with classical solid mechanics was developed to model the deflection of the rolls and strip while under load. The technique employed offers several important advantages over traditional methods to calculate strip crown, including continuity of elastic foundations, non-iterative solution when using predetermined foundation moduli, continuous third-order displacement fields, simple stress-field determination, and a comparatively faster solution time.

Resistance to High-Temperature Oxidation and Wear of Various Ferrous Alloys Used in Rolling Mills

NASA Astrophysics Data System (ADS)

Delaunois, Fabienne; Stanciu, Victor Ioan; Sinnaeve, Mario

2018-03-01

Various materials are commonly used to manufacture work rolls for hot rolling mills, such as ICDP (Indefinite Chill Double Pour) cast irons, high-chromium white cast irons, and high speed steels (HSS). Various chemical compositions and microstructures are studied in order to optimize the in-use behavior of those grades of rolls. In this paper, six grades of ferrous alloys (an ICDP cast iron; an ICDP cast iron enriched in vanadium, niobium, and molybdenum; a HSS; a graphitic HSS; a high-chromium white cast iron (Hi-Cr); and a niobium-molybdenum-doped high-chromium white cast iron) were investigated. High-temperature oxidation tests with gravimetric means at 575 °C in water vapor atmosphere and sliding wear tests were carried out. The oxidation kinetics was followed during oxidation test. The microstructure was observed by optical and scanning electron microscopies. The oxides formed on the surface of the samples were analyzed by XRD and EDS. The thickness of the oxide scales and the mass gain were measured after oxidation test. The results showed that the behavior of all the grades differed. The oxide scale of HSS and HSS-G grades was fine and their friction coefficient was low. The weight gain after oxidation test of HSS was high. Hi-Cr and M-Hi-Cr grades presented highly porous oxide layer and an important increase of the friction coefficient during wear test. ICDP and M-ICDP had intermediate behavior.

Influence of Sintering Temperature on Mechanical and Physical properties of Mill Scale based Bipolar Plates for PEMFC

NASA Astrophysics Data System (ADS)

Khaerudini, Deni S.; Berliana, Rina; Prakoso, Gatra B.; Insiyanda, Dita R.; Alva, Sagir

2018-03-01

This work concerns the utilization of mill scale, a by-product of iron and steel formed during the hot rolling of steel, as a potential material for use as bipolar plates in proton exchange membrane fuel cells (PEMFCs). On the other hand, mill scale is considered a very rich in iron source having characteristic required such as for current collector in bipolar plate and would significantly contribute to lower the overall cost of PEMFC based fuel cell systems. In this study, the iron reach source of mill scale powder, after sieving of 150 mesh, was mechanically alloyed with the aluminium source containing 30 wt.% using a shaker mill for 3 h. The mixed powders were then pressed at 300 MPa and sintered at various temperatures of 400, 450 and 500 °C for 1 h under inert gas atmosphere. The structural changes of powder particles during mechanical alloying and after sintering were studied by x-ray diffractometry, scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX), microhardness measurement, and density - porosity analysis. The details of the performance variation of three different sintering conditions can be preliminary explained by the metallographic and crystallographic structure and phase analysis as well as sufficient mechanical strength of the sintered materials was presented in this report.

Taylorwilson four roll straightener of the no. 1 seamless line ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Taylor-wilson four roll straightener of the no. 1 seamless line in bay 12 of the main pipe mill building. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

SASS Applied to Optimum Work Roll Profile Selection in the Hot Rolling of Wide Steel

NASA Astrophysics Data System (ADS)

Nolle, Lars

The quality of steel strip produced in a wide strip rolling mill depends heavily on the careful selection of initial ground work roll profiles for each of the mill stands in the finishing train. In the past, these profiles were determined by human experts, based on their knowledge and experience. In previous work, the profiles were successfully optimised using a self-organising migration algorithm (SOMA). In this research, SASS, a novel heuristic optimisation algorithm that has only one control parameter, has been used to find the optimum profiles for a simulated rolling mill. The resulting strip quality produced using the profiles found by SASS is compared with results from previous work and the quality produced using the original profile specifications. The best set of profiles found by SASS clearly outperformed the original set and performed equally well as SOMA without the need of finding a suitable set of control parameters.

Controlled cooling technology for bar and rod mills -- Computer simulation and operational results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mauk, P.J.; Kruse, M.; Plociennik, U.

The Controlled Cooling Technology (CCT) developed by SMS to simulate the rolling process and automatic control of the water cooling sections is presented. The Controlled Rolling and Cooling Technology (CRCT) model is a key part of the CCT system. It is used to simulate temperature management for the rolling stock on the computer before the actual rolling process takes place. This makes it possible to dispense with extensive rolling tests in the early stages of project planning and to greatly reduce the extent of such tests prior to the start of commercial production in a rolling mill. The CRCT modelmore » has been in use at Von Moos Stahl Ag for three years. It demonstrates that, by targeted improvement of the set-up values in both the technology and the plant, it is possible to improve microstructure quality and achieve better geometrical parameters in the rolled products. Also, the results gained with the CCT system in practical operation at the Kia Steel Bar Mill, Kunsan, Korea, are presented.« less

An investigation into the design and performance of an automatic shape control system for a Sendzimir cold rolling mill

NASA Astrophysics Data System (ADS)

Dutton, Kenneth

Shape (or flatness) control for rolled steel strip is becoming increasingly important as customer requirements become more stringent. Automatic shape control is now more or less mandatory on all new four-high cold mills, but no comprehensive scheme yet exists on a Sendzimir mill. This is due to the complexity of the control system design on such a mill, where many more degrees of freedom for control exist than is the case with the four-high mills.The objective of the current work is to develop, from first principles, such a system; including automatic control of the As-U-Roll and first intermediate roll actuators in response to the measured strip shape. This thesis concerns itself primarily with the As-U-Roll control system. The material presented is extremely wide-ranging. Areas covered include the development of original static and dynamic mathematical models of the mill systems, and testing of the plant by data-logging to tune these models. A basic control system philosophy proposed by other workers is modified and developed to suit the practical system requirements and the data provided by the models. The control strategy is tested by comprehensive multivariable simulation studies. Finally, details are given of the practical problems faced when installing the system on the plant. These include problems of manual control inter-action bumpless transfer and integral desaturation.At the time of presentation of the thesis, system commissioning is still in progress and production results are therefore not yet available. Nevertheless, the simulation studies predict a successful outcome, although performance is expected to be limited until the first intermediate roll actuators are eventually included in the scheme also.

Looking south at the aetna standard piercer and mannesman rolls ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Looking south at the aetna standard piercer and mannesman rolls of the no. 2 seamless line in bay 19 of the main pipe mill building. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

Rolling Process Modeling Report. Finite-Element Model Validation and Parametric Study on various Rolling Process parameters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Soulami, Ayoub; Lavender, Curt A.; Paxton, Dean M.

2015-06-15

Pacific Northwest National Laboratory (PNNL) has been investigating manufacturing processes for the uranium-10% molybdenum alloy plate-type fuel for high-performance research reactors in the United States. This work supports the U.S. Department of Energy National Nuclear Security Administration’s Office of Material Management and Minimization Reactor Conversion Program. This report documents modeling results of PNNL’s efforts to perform finite-element simulations to predict roll-separating forces for various rolling mill geometries for PNNL, Babcock & Wilcox Co., Y-12 National Security Complex, Los Alamos National Laboratory, and Idaho National Laboratory. The model developed and presented in a previous report has been subjected to further validationmore » study using new sets of experimental data generated from a rolling mill at PNNL. Simulation results of both hot rolling and cold rolling of uranium-10% molybdenum coupons have been compared with experimental results. The model was used to predict roll-separating forces at different temperatures and reductions for five rolling mills within the National Nuclear Security Administration Fuel Fabrication Capability project. This report also presents initial results of a finite-element model microstructure-based approach to study the surface roughness at the interface between zirconium and uranium-10% molybdenum.« less

Modeling of thermomechanical and metallurgical phenomena in steel strip during hot direct rolling and runout table cooling of thin-cast slabs

NASA Astrophysics Data System (ADS)

Muojekwu, Cornelius Anaedu

The present research was directed at adequate prediction of the temperature, deformation behavior (roll force, flow stress, strain and strain rate) and microstructural evolution (recovery, recrystallization, grain growth, austenite and ferrite grain sizes) during rolling in the Compact Strip Production (CSP) process, as well as the final mechanical properties of the hot rolled strips. This was accomplished with the aid of integrated process modeling, involving mathematical simulation, laboratory experiments and industrial campaigns. The study covered two conventional plain carbon steel grades, the A36 (AISI 1018, 0.17C-0.74Mn) and DQSK (AISI 1005, 0.038C-0.3Mn), and a range of plain carbon steel grades (0.06-0.09 C, 0.16-0.9 Mn) produced at HYLSA's CSP mill at Monterrey, Mexico. In the laboratory, compression tests (both single and double-hits) were carried out on the Gleeble 1500 thermomechanical simulator in order to elucidate the effect of coarse austenite grain size on the flow stress and recrystallization behavior of the plain carbon steels. It was found that coarse grain size not only decreased the flow stress at a given strain but also substantially reduced the tendency toward dynamic recrystallization. An increase in grain size from 244 to 1110 mum which is typical of the first stands of a conventional finishing mill and CSP hot-strip mill respectively, resulted in up to a 30 MPa decrease in the flow stress of both A36 and DQSK steel grades at similar operating conditions of temperature, strain and strain rate. In order to validate the model and laboratory results with mill measurements from an operating CSP plant, an industrial trial was carried out at HYLSA's CSP mill in Monterrey, Mexico. During the industrial campaign, intermediate temperature measurements were made, CSP slab and coil samples were acquired, and all measured and recorded mill data and practices were obtained. Comprehensive mathematical modeling of the rolling process was carried out employing finite difference and finite element analysis. The CSP mill measurements were utilized to validate model predictions of temperature, roll force, grain size and mechanical properties. Good agreement was obtained between prediction and measurement in most of the cases. An estimate of the heat extraction from the various mill sub-units was conducted from the validated calculations. It was found that heat loss by radiation accounted for 48-51 percent of the total heat loss, the work rolls accounted for 41-44 percent, the descaling unit accounted for 4-6 percent and the interstand sprays accounted for the remaining 3-4 percent. It was found that the uniform strain model consistently predicts lower temperatures than the target exit temperature for thin gauges due to a low estimate of deformation heat. Model results captured the details of heat transfer, deformation, recrystallization and austenite decomposition in the CSP mill. The effect of various mill parameters were elucidated, and the similarities and differences between conventional cold-charge rolling and CSP rolling were highlighted. (Abstract shortened by UMI.)

Effect of graphite addition into mill scale waste as a potential bipolar plates material of proton exchange membrane fuel cells

NASA Astrophysics Data System (ADS)

Khaerudini, D. S.; Prakoso, G. B.; Insiyanda, D. R.; Widodo, H.; Destyorini, F.; Indayaningsih, N.

2018-03-01

Bipolar plates (BPP) is a vital component of proton exchange membrane fuel cells (PEMFC), which supplies fuel and oxidant to reactive sites, remove reaction products, collects produced current and provide mechanical support for the cells in the stack. This work concerns the utilization of mill scale, a by-product of iron and steel formed during the hot rolling of steel, as a potential material for use as BPP in PEMFC. On the other hand, mill scale is considered a very rich in iron source having characteristic required such as for current collector in BPP and would significantly contribute to lower the overall cost of PEMFC based fuel cell systems. In this study, the iron reach source of mill scale powder, after sieving of 150 mesh, was mechanically alloyed with the carbon source containing 5, 10, and 15 wt.% graphite using a shaker mill for 3 h. The mixed powders were then pressed at 300 MPa and sintered at 900 °C for 1 h under inert gas atmosphere. The structural changes of powder particles during mechanical alloying and after sintering were studied by X-ray diffractometry, optical microscopy, scanning electron microscopy, and microhardness measurement. The details of the presence of iron, carbon, and iron carbide (Fe-C) as the products of reactions as well as sufficient mechanical strength of the sintered materials were presented in this report.

Investigation of Phosphate-Containing Salt Melts as High-Temperature Inorganic Lubricants for Metallurgical Processes,

DTIC Science & Technology

The data obtained from the results of oscillographic investigations of the use of saline inorganic lubricants in the pilger mill rolling of steel...for experimental testing as lubricants in pilger mill pipe rolling. It is shown that with the use of the above developed compositions as high

Optimization of the Technological Synthesis of Refractory Compounds

NASA Astrophysics Data System (ADS)

Gaidar, S. M.; Karelina, M. Yu.; Prikhod'ko, V. M.; Volkov, A. A.

2017-12-01

The results of experimental studies, which are related to the regulation of the fractional composition of refractory compounds by roll milling in using controlled roll opening and unbalanced peripheral speeds of rollers, are reported. The content of prepared fine, middle, and coarse fractions is within 50-80%; in this case, the milling time of synthesis products is less than the time of ball milling by an order of magnitude. The application of roll milling for refining the products of self-propagating high-temperature synthesis can be most efficient in using together with heat-generating reactor to solve the main problem of self-propagating synthesis (SHS), which is a problem for recent several decades (the problem is the creation of intense automated production of refractory compounds in using continuous manufacturing cycle within a energotechnological system with the recovery of a great quantity of heat released during SHS).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joshi, Vineet V.; Paxton, Dean M.; Lavender, Curt A.

Over the past several years Pacific Northwest National Laboratory (PNNL) has been actively involved in supporting the U.S. Department of Energy National Nuclear Security Administration Office of Material Management and Minimization (formerly Global Threat Reduction Initiative). The U.S. High- Power Research Reactor (USHPRR) project is developing alternatives to existing highly enriched uranium alloy fuel to reduce the proliferation threat. One option for a high-density metal fuel is uranium alloyed with 10 wt% molybdenum (U-10Mo). Forming the U-10Mo fuel plates/foils via rolling is an effective technique and is actively being pursued as part of the baseline manufacturing process. The processing ofmore » these fuel plates requires systematic investigation/understanding of the pre- and post-rolling microstructure, end-state mechanical properties, residual stresses, and defects, their effect on the mill during processing, and eventually, their in-reactor performance. In the work documented herein, studies were conducted to determine the effect of cold and hot rolling the as-cast and homogenized U-10Mo on its microstructure and hardness. The samples were homogenized at 900°C for 48 h, then later annealed for several durations and temperatures to investigate the effect on the material’s microstructure and hardness. The rolling of the as-cast plate, both hot and cold, was observed to form a molybdenum-rich and -lean banded structure. The cold rolling was ineffective, and in some cases exacerbated the as-cast defects. The grains elongated along the rolling direction and formed a pancake shape, while the carbides fractured perpendicularly to the rolling direction and left porosity between fractured particles of UC. The subsequent annealing of these samples at sub-eutectoid temperatures led to rapid precipitation of the ' lamellar phase, mainly in the molybdenum-lean regions. Annealing the samples above the eutectoid temperature did not refine the grain size or the banded microstructure. However, annealing the samples led to quick recovery in hardness as evidenced by a drop in Vickers hardness of 20%. Hot rolling was performed at 650 and 800°C. The hot-rolling mill loads (load separation force) were approximately 40 to 50% less than the cold-rolling for the same reduction and thickness. It was observed that hot rolling the samples with 50% or more reduction in thickness were responsible for dynamic recrystallization in the hot-rolled samples and led to grain refinement. Unlike the cold-rolled samples, the hot-rolled samples did not fracture the carbides and appeared to heal the casting defects. The recovery phenomenon was similar to the cold-rolled samples above the eutectoid temperatures, but owing to the refined grain size, the precipitation of the lamellar phase was far more rapid in these samples and the hardness increased more rapidly than in the cold rolled sample when heated below the eutectoid temperature. The data generated from these rolling efforts has been used to make the process modeling efforts more robust and applicable to all USHPRR partner rolling mills. The flow stress for cold rolling the samples was determined to be between 170-190 ksi, with frictional forces between 0.2 and 0.4 for the PNNL mill. The measured roll separation forces and those simulated using finite element methods for hot and cold rolling for the PNNL rolling mill were in good agreement.« less

Milling dynamics. I - Attritor dynamics: Results of a cinematographic study

NASA Technical Reports Server (NTRS)

Rydin, R. W.; Maurice, D.; Courtney, T. H.

1993-01-01

The motions of grinding media and powder in an attritor canister were studied by means of filming the agitated charge and frame-by-frame scrutiny of the footage. In conjunction with auxiliary experiments, this permitted semiquantitative analysis of the milling action. In particular, the mill can be divided into several regions characterized by different balances between direct impacts and rolling/sliding of the grinding media. Simple calculations suggest that impacts are more capable of effecting mechanical alloying (MA) than are rolling or sliding events in an attritor. Powder circulation within an operating mill was also investigated. Based on the results and the accompanying analysis, concepts for improved attritor design are presented.

A static model of a Sendzimir mill for use in shape control

NASA Astrophysics Data System (ADS)

Gunawardene, G. W. D. M.

The design of shape control systems is an area of current interest in the steel industry. Shape is defined as the internal stress distribution resulting from a transverse variation in the reduction of the strip thickness. The object of shape control is to adjust the mill so that the rolled strip is free from internal stresses. Both static and dynamic models of the mill are required for the control system design.The subject of this thesis is the static model of the Sendzimir cold rolling mill, which is a 1-2-3-4 type cluster mill. The static model derived enables shape profiles to be calculated for a given set of actuator positions, and is used to generate the steady state mill gains. The method of calculation of these shape profiles is discussed. The shape profiles obtained for different mill schedules are plotted against the distance across the strip. The corresponding mill gains are calculated and these relate the shape changes to the actuator changes. These mill gains are presented in the form of a square matrix, obtained by measuring shape at eight points across the strip.

1. Front view of steam engine and mill, looking NE, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Front view of steam engine and mill, looking NE, showing (l to r) 6-column beam engine, flywheel, reduction gears and 3-roll cane mill. - Hacienda Azucarera La Esperanza, Steam Engine & Mill, 2.65 Mi. N of PR Rt. 2 Bridge over Manati River, Manati, Manati Municipio, PR

31. RW Meyer Sugar Mill: 18761889. Threeroll sugar mill: oneton ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

31. RW Meyer Sugar Mill: 1876-1889. Three-roll sugar mill: one-ton daily processing capacity. Manufactured by Edwin Maw, Liverpool, England, ca. 1855-1870. View: View down at the mill from top of the mill's circular masonry enclosure. Mill animals circling above the mill, on top of the enclosure, dragged booms radiating from the drive shaft to power the mill. The drive-shaft is no longer in its upright positon but is lying next to the mill in the foreground. - R. W. Meyer Sugar Mill, State Route 47, Kualapuu, Maui County, HI

29 CFR 1910.216 - Mills and calenders in the rubber and plastics industries.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 5 2010-07-01 2010-07-01 false Mills and calenders in the rubber and plastics industries... Guarding § 1910.216 Mills and calenders in the rubber and plastics industries. (a) General requirements— (1... installed in accordance with this section and Subpart S of this part. (4) Mill roll heights. All new mill...

EAST ELEVATION, LTV STEEL (FORMERLY REPUBLIC STEEL), 8" BAR MILL, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

EAST ELEVATION, LTV STEEL (FORMERLY REPUBLIC STEEL), 8" BAR MILL, BUFFALO PLANT. VIEW LOOKING SOUTHWEST FROM ROLL SHOP. 8" BAR MILL DESIGNED AND BUILT BY DONNER STEEL CO. (PREDECESSOR OF REPUBLIC), 1919-1920. FOR DESCRIPTION OF ORIGINAL MILL SEE "IRON AGE", 116\\4 (23 JULY 1925): 201-204. - LTV Steel, 8-inch Bar Mill, Buffalo Plant, Buffalo, Erie County, NY

1. RW Meyer Sugar Mill: 18761889. Threeroll sugar mill: oneton ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. RW Meyer Sugar Mill: 1876-1889. Three-roll sugar mill: one-ton daily processing capacity. Manufactured by Edwin Maw, Liverpool, England, ca. 1855-1870. View: Historical view, 1934, from T.T. Waterman collection, Hawaiian Sugar Planters' Association. Large rectangular piece lying in front of the mill is the top of the mill frame appearing in its proper place in 1928 views. - R. W. Meyer Sugar Mill, State Route 47, Kualapuu, Maui County, HI

CONTROL FOR ROLLING MILL

DOEpatents

Shuck, A.B.; Shaw, W.C.

1961-06-20

A plutonium-rolling apparatus is patented that has two sets of feed rolls, shaping rolls between the feed rolls, and grippers beyond the feed rolls, which ready a workpiece for a new pass through the shaping rolls by angularly shifting the workpiece about its axis or transversely moving it on a line parallel to the axes of the shaping rolls. Actuation of each gripper for gripping or releasing the workpiece is produced by the relative positions assumed by the feed rolls adjacent to the gripper as the workpiece enters or leaves the feed rolls.

40 CFR 420.101 - Specialized definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... AND STANDARDS IRON AND STEEL MANUFACTURING POINT SOURCE CATEGORY Cold Forming Subcategory § 420.101 Specialized definitions. (a) The term recirculation means those cold rolling operations which include recirculation of rolling solutions at all mill stands. (b) The term combination means those cold rolling...

40 CFR 420.101 - Specialized definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... AND STANDARDS IRON AND STEEL MANUFACTURING POINT SOURCE CATEGORY Cold Forming Subcategory § 420.101 Specialized definitions. (a) The term recirculation means those cold rolling operations which include recirculation of rolling solutions at all mill stands. (b) The term combination means those cold rolling...

40 CFR 420.101 - Specialized definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... AND STANDARDS IRON AND STEEL MANUFACTURING POINT SOURCE CATEGORY Cold Forming Subcategory § 420.101 Specialized definitions. (a) The term recirculation means those cold rolling operations which include recirculation of rolling solutions at all mill stands. (b) The term combination means those cold rolling...

40 CFR 420.101 - Specialized definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... AND STANDARDS IRON AND STEEL MANUFACTURING POINT SOURCE CATEGORY Cold Forming Subcategory § 420.101 Specialized definitions. (a) The term recirculation means those cold rolling operations which include recirculation of rolling solutions at all mill stands. (b) The term combination means those cold rolling...

Anisotropy of mechanical and thermal properties of AZ31 sheets prepared using the ARB technique

NASA Astrophysics Data System (ADS)

Halmešová, K.; Trojanová, Z.; Džugan, J.; Drozd, Z.; Minárik, P.; Knapek, M.

2017-07-01

In the accumulative roll bonding (ARB) technique, repeated stacking of material followed by conventional roll-bonding is carried out. For this process the surfaces are cleaned with ethanol and then joined together by rolling. The rolled material is then cut into two halves, again surface treated and roll-bonded. This process may be repeated several times. For the magnesium alloy AZ31 (Mg-3Al-1Zn) rolling at an elevated temperature of 400 °C is necessary for ARB because of the low plasticity of hexagonal magnesium alloys at lower temperatures. Samples for this study were prepared using 1 to 3 ARB passes through the rolling mill. It was found that the ARB substantially refined the grain size of sheets to the micrometer scale. The microstructure and texture of the deformed samples were studied by light and electron microscopy. The mechanical properties of the ARB samples were explored using tensile test-pieces cut from the sheets with the tensile axis taken either parallel or perpendicular to the rolling direction, where a significant anisotropy in both mechanical properties and Young’s modulus was found. Anisotropy is explained on the basis of the specific microstructure and texture formed during the ARB process.

Neponset River Basin Massachusetts, Flood Plain Management Study.

DTIC Science & Technology

1982-03-01

extensive water power. There are in the southern village, two rolling mills, for the manufacture of copper bolts and sheathing, on a large scale; two...furnaces for refining copper , and casting bells and brass cannon (operated by Paul Revere): forges and furnaces for the manufacture of iron wheels and...Dedha Granodiorite, Westwood Granite, Sharon Syenite, and Blue Rills Granite Porphyry . Crushed Stone. The Mattapan Volcanic Complex and Westwood

30. RW Meyer Sugar Mill: 18761889. Threeroll sugar mill: oneton ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

30. RW Meyer Sugar Mill: 1876-1889. Three-roll sugar mill: one-ton daily processing capacity. Manufactured by Edwin Maw, Liverpool, England, ca. 1885-1870. View: Masonry-lined passage-way leading to the mill at the center of its circular masonry enclosure. The passageway permitted cane to be carried to the mill and cane trash (bagasse) to be carried away. Bridges over the passageways, no longer in place, permitted the mill animals to circle and power the mill from above. - R. W. Meyer Sugar Mill, State Route 47, Kualapuu, Maui County, HI

Rolling Mill Hill, Nashville, TN

EPA Pesticide Factsheets

Rolling Mill Hill was the home to Nashville General Hospital from 1890 to the 1990s and encompassed several buildings and structures. These existing buildings of historical significance were re-used in the form of apartments. The original Trolley Barns on the site are now artists’ lofts and are home to several companies and non-profit offices. Nance Place, which entails additional buildings built on-site, is a Tax Credit Workforce Housing Development and is Platinum LEED certified.

Recycle of valuable products from oily cold rolling mill sludge

NASA Astrophysics Data System (ADS)

Liu, Bo; Zhang, Shen-gen; Tian, Jian-jun; Pan, De-an; Liu, Yang; Volinsky, Alex A.

2013-10-01

Oily cold rolling mill (CRM) sludge contains lots of iron and alloying elements along with plenty of hazardous organic components, which makes it as an attractive secondary source and an environmental contaminant at the same time. The compound methods of "vacuum distillation + oxidizing roasting" and "vacuum distillation + hydrogen reduction" were employed for the recycle of oily cold rolling mill sludge. First, the sludge was dynamically vacuum distilled in a rotating furnace at 50 r/min and 600°C for 3 h, which removed almost hazardous organic components, obtaining 89.2wt% ferrous resultant. Then, high purity ferric oxide powders (99.2wt%) and reduced iron powders (98.9wt%) were obtained when the distillation residues were oxidized and reduced, respectively. The distillation oil can be used for fuel or chemical feedstock, and the distillation gases can be collected and reused as a fuel.

Assessment of a miniature four-roll mill and a cross-slot microchannel for high-strain-rate stagnation point flows

NASA Astrophysics Data System (ADS)

Akbaridoust, Farzan; Philip, Jimmy; Marusic, Ivan

2018-04-01

Stagnation point flows have been widely used to study the deformation and break-up of objects in two-dimensional pure straining flows. Here, we report a systematic study of the characterisation of stagnation point flows in two devices, a miniature Taylor’s four-roll mill and a cross-slot microchannel. The aim of the study is to find the best platform suitable for investigating the effect of strain rate on the mechanical properties of waterborne microorganisms. Using micro-PIV, the velocity field and the strain rates in both devices were measured at different flow rates and compared with an ideal hyperbolic stagnation point flow. The cross-slot microchannel was found to be a better experimental device than the miniature four-roll mill for the purpose of confining micron-sized objects in a controlled stagnation point flow. This is mainly due to the difficulty of maintaining a fixed location for the stagnation point within one micron in the miniature four-roll mill and achieving high strain rates beyond 10 s-1 . However, with no moving parts, the cross-slot microchannel was found to maintain a steady flow, with the stagnation point varying less than one micron at a cross-junction of 400× 400~μm2 , and was able to reach uniform strain rates up to 140 s-1 .

Detection of internally infested popcorn using electrically conductive roller mills

USDA-ARS?s Scientific Manuscript database

To detect popcorn kernels infested by the internal feeding stored-product insect pest Sitophilus zeamais, maize weevil, a laboratory roller mill was modified so that the electrical conductivity of the grain is measured while the kernels are milled between the rolls. When a kernel with a S. zeamais l...

Using CCT Diagrams to Optimize the Composition of an As-Rolled Dual-Phase Steel

NASA Astrophysics Data System (ADS)

Coldren, A. Phillip; Eldis, George T.

1980-03-01

A continuous-cooling transformation (CCT) diagram study was conducted for the purpose of optimizing the composition of a Mn-Si-Cr-Mo as-rolled dual-phase (ARDP) steel. The individual effects of chromium, molybdenum, and silicon on the allowable cooling rates were determined. On the basis of the CCT diagram study and other available information, an optimum composition was selected. Data from recent mill trials at three steel companies, involving steels with compositions in or near the newly recommended range, are presented and compared with earlier mill trial data. The comparison shows that the optimized composition is highly effective in making the steel's properties more uniform and reproducible in the as-rolled condition.

The Role of Nano-TiO2 Lubricating Fluid on the Hot Rolled Surface and Metallographic Structure of SS41 Steel

PubMed Central

Meng, Yanan; Sun, Jianlin; Wu, Ping; Dong, Chang; Yan, Xudong

2018-01-01

In this paper, nano-TiO2lubricating fluid was chosen as an advanced rolling lubricant to investigate its effect on the hot rolled surface and metallographic structure of SS41 steel strips. The tribological performances of nano-TiO2 lubricating fluid were measured by a four-ball tribotester. The hot rolling experiments under different lubrication conditions were carried out by a four-high rolling mill. The surface morphology, oxide scales and metallographic structure after hot rolling were observed using a confocal laser scanning microscope and scanning electron microscope (SEM), respectively. The composition of surface attachments was analyzed with X-ray photoelectron spectroscopy (XPS). The results indicate that the nano-TiO2 lubricating fluid has a better tribological performance. The surface defects on the hot rolled surface could be decreased. The phase composition of the surface still appears as a mixture of ferrite and pearlite. The surface of steel strips is not micro-alloyed with titanium as predicted. Additionally, the grain size of rolled steel strips which were lubricated with the nano-TiO2lubricating fluid decreased by nearly 50%, compared with traditional lubricating fluid. Furthermore, it was found that the thickness of the oxide layers on the surface reduced, whilst the Rockwell hardness of the oxide layers was enhanced as nano-TiO2 lubricating fluid was applied. PMID:29462937

The Role of Nano-TiO2 Lubricating Fluid on the Hot Rolled Surface and Metallographic Structure of SS41 Steel.

PubMed

Meng, Yanan; Sun, Jianlin; Wu, Ping; Dong, Chang; Yan, Xudong

2018-02-16

In this paper, nano-TiO2lubricating fluid was chosen as an advanced rolling lubricant to investigate its effect on the hot rolled surface and metallographic structure of SS41 steel strips. The tribological performances of nano-TiO2 lubricating fluid were measured by a four-ball tribotester. The hot rolling experiments under different lubrication conditions were carried out by a four-high rolling mill. The surface morphology, oxide scales and metallographic structure after hot rolling were observed using a confocal laser scanning microscope and scanning electron microscope (SEM), respectively. The composition of surface attachments was analyzed with X-ray photoelectron spectroscopy (XPS). The results indicate that the nano-TiO2 lubricating fluid has a better tribological performance. The surface defects on the hot rolled surface could be decreased. The phase composition of the surface still appears as a mixture of ferrite and pearlite. The surface of steel strips is not micro-alloyed with titanium as predicted. Additionally, the grain size of rolled steel strips which were lubricated with the nano-TiO2lubricating fluid decreased by nearly 50%, compared with traditional lubricating fluid. Furthermore, it was found that the thickness of the oxide layers on the surface reduced, whilst the Rockwell hardness of the oxide layers was enhanced as nano-TiO2 lubricating fluid was applied.

Interactions Forces and the Flow-Induced Coalescence of Drops and Bubbles

NASA Technical Reports Server (NTRS)

Leal, L. Gary; Israelachvili, J.

2004-01-01

In order to accomplish the proposed macroscale experimental goals, we designed and built a pair of miniaturized computer-controlled four-roll mills, similar but much smaller than the 4-roll mill that had been develop earlier in Prof. Leal's group for studies of drop deformation and breakup. This unique experimental facility allows for controlled experiments on the breakup and coalescence of very small drops in the size range of 20-200 micrometers in diameter for a wide variety of flows and under a wide range of flow conditions including time-dependent flows, etc. The small size of this device is necessary for coalescence studies, since coalescence occurs in viscous fluids at capillary numbers that are large enough to be experimentally accessible only for drops that are smaller than approximately 100_m in diameter. Using these miniaturized 4-roll mills, we have obtained the first quantitative data (so far as we are aware) on the flow-induced coalescence process.

A model for prediction of profile and flatness of hot and cold rolled flat products in four-high mills

NASA Astrophysics Data System (ADS)

Overhagen, Christian; Mauk, Paul Josef

2018-05-01

For flat rolled products, the thickness profile in the transversal direction is one of the most important product properties. For further processing, a defined crown of the product is necessary. In the rolling process, several mechanical and thermal influences interact with each other to form the strip shape at the roll gap exit. In the present analysis, a process model for rolling of strip and sheet is presented. The core feature of the process model is a two-dimensional stress distribution model based on von Karman's differential equation. Sub models for the mechanical influences of work roll flattening as well as work and backup roll deflection and the thermal influence of work roll expansion have been developed or extended. The two-dimensional stress distribution serves as an input parameter for the roll deformation models. For work roll flattening, a three-dimensional model based on the Boussinesq problem is adopted, while the work and backup roll deflection, including contact flattening is calculated by means of finite beam elements. The thermal work roll crown is calculated with help of an axisymmetric numerical solution of the heat equation for the work roll, considering azimuthal averaging for the boundary conditions at the work roll surface. Results are presented for hot rolling of a strip in a seven-stand finishing train of a hot strip mill, showing the calculated evolution of the strip profile. A variation of the strip profile from the first to the 20th rolled strip is shown. This variation is addressed to the progressive increase of work roll temperature during the first 20 strips. It is shown that a CVC® system can lead to improvements in strip profile and therefore flatness.

Recycle of mixed automotive plastics: A model study

NASA Astrophysics Data System (ADS)

Woramongconchai, Somsak

This research investigated blends of virgin automotive plastics which were identified through market analysis. The intent was that this study could be used as a basis for further research in blends of automotive plastics recyclate. The effects of temperature, shear, time, and degree of mixing in a two-roll mill, a single-screw extruder, and a twin-screw extruder were investigated. Properties were evaluated in terms of melt flow, rigidity, strength, impact, heat resistance, electrical resistivity, color, and resistance to water and gasoline. Torque rheometry, dynamic mechanical analysis (DMA), optical and scanning electron microscopy were used to characterize the processability and morphology of major components of the blends. The two-roll mill was operated at high temperature, short time, and low roll speed to avoid discolored and degraded materials. The single-screw extruder and twin-screw extruder were operated at medium and high temperature and high screw speed, respectively, for optimizing head pressure, residence time, shear and degree of mixing of the materials. Melt index increased with extrusion temperature. Flexural modulus increased with the processing temperatures in milling or twin-screw extrusion, but decreased with the increasing single-screw extrusion temperature. Tensile modulus was also enhanced by increasing processing temperature. The tensile strengths for each process were similar and relatively low. The impact strength increased with temperature and roll speed in two-roll milling, was unaffected by the single-screw extrusion temperature and decreased with increasing twin-screw extrusion temperature. Heat resistance was always reduced by higher processing temperature. The volume resistivity increased, water absorption was unaffected and gasoline absorption altered by increased processing temperature. The latter increased somewhat with mill temperature, roll speed (two-roll mill) and higher extrusion temperature (single-screw extruder), but decreased with increased twin-screw extrusion temperature. The flexural modulus of the recycled mixed automotive plastics expected in 2003 was higher than the 1980s and 1990 recycle. Flexural strength effects were not large enough for serious consideration, but were more dominant when compared to those in the 1980s and 1990s. Impact strengths at 20-30 J/m were the lowest value compared to the 1980s and 1990s mixed automotive recycle. Torque rheometry, dynamic mechanical analysis and optical and electron microscopy agreed with each other on the characterization of the processability and morphology of the blends. LLDPE and HDPE were miscible while PP was partially miscible with polyethylene. ABS and nylon-6 were immiscible with the polyolefins, but partially miscible with each other. As expected, the polyurethane foam was immiscible with the other components. The minor components of the model recycle of mixed automotive materials were probably partially miscible with ABS/nylon-6, but there were multiple and unresolved phases in the major blends.

75 FR 1031 - Certain Hot-Rolled Carbon Steel Flat Products from India: Notice of Preliminary Results of...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-08

... measuring at least 10 times the thickness. Universal mill plate (i.e., flat-rolled products rolled on four... determinations. If the Department chooses as facts available a calculated dumping margin from the investigation... questionnaire. See Certain Cut-to-Length Carbon-Quality Steel Plate Products from the Republic of Korea: Final...

Microstructure-Property Correlation in Magnesium-based Hydrogen Storage Systems: The Case for Ball-milled Magnesium Hydride Powder and Magnesium-based Multilayered Composites

NASA Astrophysics Data System (ADS)

Danaie, Mohsen

The main focus of this thesis is the characterization of defects and microstructure in high-energy ball milled magnesium hydride powder and magnesium-based multilayered composites. Enhancement in kinetics of hydrogen cycling in magnesium can be achieved by applying severe plastic deformation. A literature survey reveals that, due to extreme instability of alpha-MgH 2 in transmission electron microscope (TEM), the physical parameters that researchers have studied are limited to particle size and grain size. By utilizing a cryogenic TEM sample holder, we extended the stability time of the hydride phase during TEM characterization. Milling for only 30 minutes resulted in a significant enhancement in desorption kinetics. A subsequent annealing cycle under pressurized hydrogen reverted the kinetics to its initial sluggish state. Cryo-TEM analysis of the milled hydride revealed that mechanical milling induces deformation twinning in the hydride microstructure. Milling did not alter the thermodynamics of desorption. Twins can enhance the kinetics by acting as preferential locations for the heterogeneous nucleation of metallic magnesium. We also looked at the phase transformation characteristics of desorption in MgH2. By using energy-filtered TEM, we investigated the morphology of the phases in a partially desorbed state. Our observations prove that desorption phase transformation in MgH2 is of "nucleation and growth" type, with a substantial energy barrier for nucleation. This is contrary to the generally assumed "core-shell" structure in most of the simulation models for this system. We also tested the hydrogen storage cycling behavior of bulk centimeter-scale Mg-Ti and Mg-SS multilayer composites synthesized by accumulative roll-bonding. Addition of either phase (Ti or SS) allows the reversible hydrogen sorption at 350°C, whereas identically roll-bonded pure magnesium cannot be absorbed. In the composites the first cycle of absorption (also called "activation") kinetics improve with increased number of fold and roll (FR) operations. With increasing FR operations the distribution of the Ti phase is progressively refined, and the shape of the absorption curve no longer remains sigmoidal. Up to a point, increasing the loading amount of the second phase also accelerates the kinetics. Microscopy analysis performed on 1--2 wt.% hydrogen absorbed composites demonstrates that MgH 2 formed exclusively on various heterogeneous nucleation sites. During activation, MgH2 nucleation occurred at the Mg-hard phase interfaces. On the subsequent absorption cycles, heterogeneous nucleation primarily occurred in the vicinity of "internal" free surfaces such as cracks.

Senseless demolition in progress, showing destruction of perfectly decent and ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Senseless demolition in progress, showing destruction of perfectly decent and recyclable mill building. Problem exacerbated by high value of scrap iron. - Phoenix Iron Company, Rolling Mill, North of French Creek, west of Fairview Avenue, Phoenixville, Chester County, PA

29 CFR 570.59 - Occupations involved in the operation of power-driven metal forming, punching, and shearing...

Code of Federal Regulations, 2011 CFR

2011-07-01

... beading, straightening, corrugating, flanging, or bending rolls; and hot or cold rolling mills. (ii) All... area between the dies; power presses; and plate punches. (iii) All bending machines, such as apron...

Mathematical-Artificial Neural Network Hybrid Model to Predict Roll Force during Hot Rolling of Steel

NASA Astrophysics Data System (ADS)

Rath, S.; Sengupta, P. P.; Singh, A. P.; Marik, A. K.; Talukdar, P.

2013-07-01

Accurate prediction of roll force during hot strip rolling is essential for model based operation of hot strip mills. Traditionally, mathematical models based on theory of plastic deformation have been used for prediction of roll force. In the last decade, data driven models like artificial neural network have been tried for prediction of roll force. Pure mathematical models have accuracy limitations whereas data driven models have difficulty in convergence when applied to industrial conditions. Hybrid models by integrating the traditional mathematical formulations and data driven methods are being developed in different parts of world. This paper discusses the methodology of development of an innovative hybrid mathematical-artificial neural network model. In mathematical model, the most important factor influencing accuracy is flow stress of steel. Coefficients of standard flow stress equation, calculated by parameter estimation technique, have been used in the model. The hybrid model has been trained and validated with input and output data collected from finishing stands of Hot Strip Mill, Bokaro Steel Plant, India. It has been found that the model accuracy has been improved with use of hybrid model, over the traditional mathematical model.

12. RW Meyer Sugar Mill: 18761889. Threeroll sugar mill: oneton ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. RW Meyer Sugar Mill: 1876-1889. Three-roll sugar mill: one-ton daily processing capacity. Manufactured by Edwin Maw, Liverpool, England, ca. 1855-1870. View: Historical view, 1934, T.T. Waterman Collection, Hawaiian Sugar Planters' Association, Oahu, Hawaii. Masonry-lined passageway leading to the mill at the center of its circular masonry enclosure. The passageway permitted cane to be carried to the mill and cane trash (bagasse) to be carried away after milling. Bridges over the passageways, not in place, permitted the mill animals to circle and power the mill from above. View shows area prior to substantial overgrowth existing in 1978 views of the area. - R. W. Meyer Sugar Mill, State Route 47, Kualapuu, Maui County, HI

Properties of dispersion-strengthened chromium - 4-volume-percent-thoria alloys produced by ball milling in hydrogen iodide

NASA Technical Reports Server (NTRS)

Arias, A.

1974-01-01

The effects of processing variables on the tensile properties and ductile-to-brittle transition temperature (DBTT) of Cr + 4 vol. %ThO2 alloys and of pure Cr produced by ball milling in hydrogen iodide were investigated. Hot rolled Cr + ThO2 was stronger than either hot pressed Cr + ThO2 or pure Cr at temperatures up to 1537 C. Hot pressed Cr + ThO2 had a DBTT of 501 C as compared with minus 8 to 24 C for the hot rolled Cr + ThO2 and with 139 C for pure Cr. It is postulated that the dispersoid in the hot rolled alloys lowers the DBTT by inhibiting recovery and recrystallization of the strained structure.

Radiochronological Age of a Uranium Metal Sample from an Abandoned Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meyers, L A; Williams, R W; Glover, S E

2012-03-16

A piece of scrap uranium metal bar buried in the dirt floor of an old, abandoned metal rolling mill was analyzed using multi-collector inductively coupled plasma mass spectroscopy (MC-ICP-MS). The mill rolled uranium rods in the 1940s and 1950s. Samples of the contaminated dirt in which the bar was buried were also analyzed. The isotopic composition of uranium in the bar and dirt samples were both the same as natural uranium, though a few samples of dirt also contained recycled uranium; likely a result of contamination with other material rolled at the mill. The time elapsed since the uranium metalmore » bar was last purified can be determined by the in-growth of the isotope {sup 230}Th from the decay of {sup 234}U, assuming that only uranium isotopes were present in the bar after purification. The age of the metal bar was determined to be 61 years at the time of this analysis and corresponds to a purification date of July 1950 {+-} 1.5 years.« less

29 CFR 570.59 - Occupations involved in the operations of power-driven metal forming, punching, and shearing...

Code of Federal Regulations, 2010 CFR

2010-07-01

..., or bending rolls; and hot or cold rolling mills. (ii) All pressing or punching machines, such as... presses; and plate punches. (iii) All bending machines, such as apron brakes and press brakes. (iv) All...

Modeling of Surface Geometric Structure State After Integratedformed Milling and Finish Burnishing

NASA Astrophysics Data System (ADS)

Berczyński, Stefan; Grochała, Daniel; Grządziel, Zenon

2017-06-01

The article deals with computer-based modeling of burnishing a surface previously milled with a spherical cutter. This method of milling leaves traces, mainly asperities caused by the cutting crossfeed and cutter diameter. The burnishing process - surface plastic treatment - is accompanied by phenomena that take place right in the burnishing ball-milled surface contact zone. The authors present the method for preparing a finite element model and the methodology of tests for the assessment of height parameters of a surface geometrical structure (SGS). In the physical model the workpieces had a cuboidal shape and these dimensions: (width × height × length) 2×1×4.5 mm. As in the process of burnishing a cuboidal workpiece is affected by plastic deformations, the nonlinearities of the milled item were taken into account. The physical model of the process assumed that the burnishing ball would be rolled perpendicularly to milling cutter linear traces. The model tests included the application of three different burnishing forces: 250 N, 500 N and 1000 N. The process modeling featured the contact and pressing of a ball into the workpiece surface till the desired force was attained, then the burnishing ball was rolled along the surface section of 2 mm, and the burnishing force was gradually reduced till the ball left the contact zone. While rolling, the burnishing ball turned by a 23° angle. The cumulative diagrams depict plastic deformations of the modeled surfaces after milling and burnishing with defined force values. The roughness of idealized milled surface was calculated for the physical model under consideration, i.e. in an elementary section between profile peaks spaced at intervals of crossfeed passes, where the milling feed fwm = 0.5 mm. Also, asperities after burnishing were calculated for the same section. The differences of the obtained values fall below 20% of mean values recorded during empirical experiments. The adopted simplification in after-milling SGS modeling enables substantial acceleration of the computing process. There is a visible reduction of the Ra parameter value for milled and burnished surfaces as the burnishing force rises. The tests determined an optimal burnishing force at a level of 500 N (lowest Ra = 0.24 μm). Further increase in the value of burnishing force turned out not to affect the surface roughness, which is consistent with the results obtained from experimental studies.

27. The AssortingRoom in the paper mill. After the paper ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

27. The Assorting-Room in the paper mill. After the paper has been calendered, the big rolls are put into a cutting-machine that cuts the continuous roll into sheets of the desired size. These are then examined, sheet by sheet, by the women shown in the picture. All perfect shoes are put into one pile and the imperfect ones are placed in another pile. The perfect sheets are then ready, after trimming, for the presses of the National Geographic. (p.241.) - Champion-International Paper Company, West bank of Spicket River at Canal Street, Lawrence, Essex County, MA

3. VIEW OF INTERIOR, EAST SIDE (SIDE A) OF BUILDING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. VIEW OF INTERIOR, EAST SIDE (SIDE A) OF BUILDING 883. INSTALLATION OF EQUIPMENT FOR THE MOLTEN SALT BATHS AND ROLLING MILLS PROCESSES. (4/25/57) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

Experience of Application of Liquid Lubricating Materials during Wide Strip Hot Rolling

NASA Astrophysics Data System (ADS)

Platov, S. I.; Dema, R. R.; Kharchenko, M. V.; Amirov, R. N.

2017-12-01

The paper presents the results of the scientific and practical research of roller systems operation at feed of liquid lubricating materials through the example of the wide strip hot rolling Mill-2000 at PAO MMK. The experiments proved that application of lubricating materials leads to decrease of energy-power parameters of the process by 12 to 15 %, and reduction of work roll wear by 10 to 12%. The practical results of the study are developed recommendations on determination of consumption-volumetric parameters of the supplied lubricating material depending on rheological and geometrical parameters of the rolled strip and current wear of work rolls.

Spread prediction model of continuous steel tube based on BP neural network

NASA Astrophysics Data System (ADS)

Zhai, Jian-wei; Yu, Hui; Zou, Hai-bei; Wang, San-zhong; Liu, Li-gang

2017-07-01

According to the geometric pass of roll and technological parameters of three-roller continuous mandrel rolling mill in a factory, a finite element model is established to simulate the continuous rolling process of seamless steel tube, and the reliability of finite element model is verified by comparing with the simulation results and actual results of rolling force, wall thickness and outer diameter of the tube. The effect of roller reduction, roller rotation speed and blooming temperature on the spread rule is studied. Based on BP(Back Propagation) neural network technology, a spread prediction model of continuous rolling tube is established for training wall thickness coefficient and spread coefficient of the continuous rolling tube, and the rapid and accurate prediction of continuous rolling tube size is realized.

Research on the rolling moment in the symmetrical and asymmetrical rolling process

NASA Astrophysics Data System (ADS)

Alexa, V.; Raţiu, S. A.; Kiss, I.; Cioată, C. G.

2017-01-01

Research distribution the rolling moments symmetrical and asymmetrical report presents great importance both in theory and to introduce clarifications to the calculation of rolling resistance line assemblies. Clarifying individuals of metallic material deformation between the rolls single cylinder diameters act of any difference of work and analysis of advance and delay phenomena. Torque drive value for each of the rolling cylinders was done by reducing the thickness of the laminate samples, an experimental facility located in the laboratory of plastic deformation of the Faculty of Engineering Hunedoara. The analysis of research results show that in terms of power consumption for deformation and safety equipment in operation is rational for mills which require such a difference between the work rolls to execute about one cylinder operated.

Roll-to-Roll production of carbon nanotubes based supercapacitors

NASA Astrophysics Data System (ADS)

Zhu, Jingyi; Childress, Anthony; Karakaya, Mehmet; Roberts, Mark; Arcilla-Velez, Margarita; Podila, Ramakrishna; Rao, Apparao

2014-03-01

Carbon nanomaterials provide an excellent platform for electrochemical double layer capacitors (EDLCs). However, current industrial methods for producing carbon nanotubes are expensive and thereby increase the costs of energy storage to more than 10 Wh/kg. In this regard, we developed a facile roll-to-roll production technology for scalable manufacturing of multi-walled carbon nanotubes (MWNTs) with variable density on run-of-the-mill kitchen Al foils. Our method produces MWNTs with diameter (heights) between 50-100 nm (10-100 μm), and a specific capacitance as high as ~ 100 F/g in non-aqueous electrolytes. In this talk, the fundamental challenges involved in EDLC-suitable MWNT growth, roll-to-roll production, and device manufacturing will be discussed along with electrochemical characteristics of roll-to-roll MWNTs. Research supported by NSF CMMI Grant1246800.

Influence of Accumulative Roll Bonding on the Texture and Tensile Properties of an AZ31 Magnesium Alloy Sheets

PubMed Central

Džugan, Ján; Németh, Gergely; Lukáč, Pavel; Bohlen, Jan

2018-01-01

Deformation behaviour of rolled AZ31 sheets that were subjected to the accumulative roll bonding was investigated. Substantially refined microstructure of samples was achieved after the first and second pass through the rolling mill. Sheets texture was investigated using an X-ray diffractometer. Samples for tensile tests were cut either parallel or perpendicular to the rolling direction. Tensile tests were performed at temperatures ranging from room temperature up to 300 °C. Tensile plastic anisotropy, different from the anisotropy observed in AZ31 sheets by other authors, was observed. This anisotropy decreases with an increasing number of rolling passes and increasing deformation temperature. Grain refinement and texture are the crucial factors influencing the deformation behaviour. PMID:29303975

16. 3RD FLOOR, J.M. LEHMANN CO. FIVEROLL TOILET SOAP MILL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. 3RD FLOOR, J.M. LEHMANN CO. FIVE-ROLL TOILET SOAP MILL INSTALLED 1950, TO WEST; BUCKET CONVEYOR AT RIGHT MOVED WASTE FROM 2ND FLOOR SOAP PRESSES TO 5TH FLOOR RE-MANUFACTURE - Colgate & Company Jersey City Plant, Building No. B-14, 54-58 Grand Street, Jersey City, Hudson County, NJ

Report on Northwestern's Air-cooled, Copper Precipitation Hardened, High Strength, Weldable Steel Cast and Hot Rolled at Oregon Steel Mills

DOT National Transportation Integrated Search

1996-09-27

This research has shown that a Grade 70 construction steel of 1/2- to 1-inch plate thicknesses can be produced without a quench and temper or accelerated cooling from hot-rolling if the Cu content in the steel is sufficiently high. Coherent very fine...

41. 44INCH SOAKING PITS. A MORGAN CRANE LOWERS THE STEEL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

41. 44-INCH SOAKING PITS. A MORGAN CRANE LOWERS THE STEEL INGOT INTO A 'SOAKING PIT,' WHERE IT IS HEATED TO A UNIFORM TEMPERATURE PRIOR TO ROLLING. THE INGOT RECEIVES ITS FIRST ROLLING ON THE 44-INCH BLOOMING MILL. - Corrigan, McKinney Steel Company, 3100 East Forty-fifth Street, Cleveland, Cuyahoga County, OH

Increased compactibility of acetames after roll compaction.

PubMed

Kuntz, Theresia; Schubert, Martin A; Kleinebudde, Peter

2011-01-01

A common technique for manufacturing granules in a continuous way is the combination of roll compaction and subsequent milling. Roll compaction can considerably impact tableting performance of a material. The purpose of this study was to investigate the influence of roll compaction/dry granulation on the compaction behavior of acetames, a class of active pharmaceutical substances, which are mainly used for the treatment of central nervous diseases. Some representatives of acetames were roll compacted and then compressed into tablets. Compactibility of granules was compared with the compaction behavior of the directly compressed drug powders. In contrast to many other materials, the roll compaction step induced an increase in compactibility for all investigated acetames. Specific surface areas of the untreated and the roll compacted drugs were determined by nitrogen adsorption. The raise in compactibility observed was accompanied by an increase in specific surface area during roll compaction. Copyright © 2010 Elsevier B.V. All rights reserved.

Low-Carbon Metallurgical Concepts for Seamless Octg Pipe

NASA Astrophysics Data System (ADS)

Mohrbacher, Hardy

Seamless pipes are available with wall gages of up to 100 mm and outer diameters up to around 700 mm. Such pipes are typically used for oil country tubular goods as well as for structural applications. Due to market requirements the demand for high strength grade seamless pipes is increasing. Many applications need high toughness in addition to high strength. The different rolling processes applied in production depend on wall gage and pipe diameter. The continuous mandrel mill process is used to produce smaller gages and diameters; plug mill processing covers medium gages and diameters; Pilger mill processing allows producing larger diameters and heavy wall gage. In all these processes only a limited degree of thermo-mechanical rolling can be achieved. Therefore strengthening and toughening by severe grain refinement employing a conventional niobium-based microalloying concept is not easily achievable. Accordingly, high strength and toughness seamless pipe is typically produced via a quench and tempering process route. This route however is costly and above that often constitutes a capacity bottleneck in the mill. Innovative low-carbon alloy concepts however do allow producing strength up to grade X70 at very high toughness directly off the rolling plant, i.e., without quench and tempering treatment. Due to the low carbon content also welding is much facilitated. The paper reveals the metallurgical principles, which are based on appropriate niobium and molybdenum alloying. Additionally the paper demonstrates how heavy gaged seamless pipes up to 70 mm wall thickness can be produced based on a low-carbon Nb-Mo approach using quench and temper treatment.

Investigation of the influence of the chemical composition of HSLA steel grades on the microstructure homogeneity during hot rolling in continuous rolling mills using a fast layer model

NASA Astrophysics Data System (ADS)

Schmidtchen, M.; Rimnac, A.; Warczok, P.; Kozeschnik, E.; Bernhard, C.; Bragin, S.; Kawalla, R.; Linzer, B.

2016-03-01

The newly developed LaySiMS simulation tool provides new insight for inhomogeneous material flow and microstructure evolution in an endless strip production (ESP) plant. A deepened understanding of the influence of inhomogeneities in initial material state, temperature profile and material flow and their impact on the finished product can be reached e.g. by allowing for variable layer thickness distributions in the roll gap. Coupling temperature, deformation work and work hardening/recrystallization phenomena accounts for covering important effects in the roll gap. The underlying concept of the LaySiMS approach will be outlined and new insight gained regarding microstructural evolution, shear and inhomogeneous stress and strain states in the roll gap as well as local residual stresses will be presented. For the case of thin slab casting and direct rolling (TSDR) the interrelation of inhomogeneous initial state, micro structure evolution and dissolution state of micro alloying elements within the roughing section of an ESP line will be discussed. Special emphasis is put on the influence of the local chemical composition arising from direct charging on throughthickness homogeneity of the final product. It is concluded that, due to the specific combination of large reductions in the high reduction mills (HRM) and the highly inhomogeneous inverse temperature profile, the ESP-concept provides great opportunities for homogenizing the microstructure across the strip thickness.

Fault Diagnosis for Centre Wear Fault of Roll Grinder Based on a Resonance Demodulation Scheme

NASA Astrophysics Data System (ADS)

Wang, Liming; Shao, Yimin; Yin, Lei; Yuan, Yilin; Liu, Jing

2017-05-01

Roll grinder is one of the important parts in the rolling machinery, and the grinding precision of roll surface has direct influence on the surface quality of steel strip. However, during the grinding process, the centre bears the gravity of the roll and alternating stress. Therefore, wear or spalling faults are easily observed on the centre, which will lead to an anomalous vibration of the roll grinder. In this study, a resonance demodulation scheme is proposed to detect the centre wear fault of roll grinder. Firstly, fast kurtogram method is employed to help select the sub-band filter parameters for optimal resonance demodulation. Further, the envelope spectrum are derived based on the filtered signal. Finally, two health indicators are designed to conduct the fault diagnosis for centre wear fault. The proposed scheme is assessed by analysing experimental data from a roll grinder of twenty-high rolling mill. The results show that the proposed scheme can effectively detect the centre wear fault of the roll grinder.

Design of preventive maintenance system using the reliability engineering and maintenance value stream mapping methods in PT. XYZ

NASA Astrophysics Data System (ADS)

Sembiring, N.; Panjaitan, N.; Angelita, S.

2018-02-01

PT. XYZ is a company owned by non-governmental organizations engaged in the field of production of rubber processing becoming crumb rubber. Part of the production is supported by some of machines and interacting equipment to achieve optimal productivity. Types of the machine that are used in the production process are Conveyor Breaker, Breaker, Rolling Pin, Hammer Mill, Mill Roll, Conveyor, Shredder Crumb, and Dryer. Maintenance system in PT. XYZ is corrective maintenance i.e. repairing or replacing the engine components after the crash on the machine. Replacement of engine components on corrective maintenance causes the machine to stop operating during the production process is in progress. The result is in the loss of production time due to the operator must replace the damaged engine components. The loss of production time can impact on the production targets which were not reached and lead to high loss costs. The cost for all components is Rp. 4.088.514.505. This cost is really high just for maintaining a Mill Roll Machine. Therefore PT. XYZ is needed to do preventive maintenance i.e. scheduling engine components and improving maintenance efficiency. The used methods are Reliability Engineering and Maintenance Value Stream Mapping (MVSM). The needed data in this research are the interval of time damage to engine components, opportunity cost, labor cost, component cost, corrective repair time, preventive repair time, Mean Time To Opportunity (MTTO), Mean Time To Repair (MTTR), and Mean Time To Yield (MTTY). In this research, the critical components of Mill Roll machine are Spier, Bushing, Bearing, Coupling and Roll. Determination of damage distribution, reliability, MTTF, cost of failure, cost of preventive, current state map, and future state map are done so that the replacement time for each critical component with the lowest maintenance cost and preparation of Standard Operation Procedure (SOP) are developed. For the critical component that has been determined, the Spier component replacement time interval is 228 days with a reliability value of 0,503171, Bushing component is 240 days with reliability value of 0.36861, Bearing component is 202 days with reliability value of 0,503058, Coupling component is 247 days with reliability value of 0,50108 and Roll component is 301 days with reliability value of 0,373525. The results show that the cost decreases from Rp 300,688,114 to Rp 244,384,371 obtained from corrective maintenance to preventive maintenance. While maintenance efficiency increases with the application of preventive maintenance i.e. for Spier component from 54,0540541% to 74,07407%, Bushing component from 52,3809524% to 68,75%, Bearing component from 40% to 52,63158%, Coupling component from 60.9756098% to 71.42857%, and Roll components from 64.516129% to 74.7663551%.

41 CFR 50-204.5 - Machine guarding.

Code of Federal Regulations, 2011 CFR

2011-07-01

... usually require point of operation guarding: Guillotine cutters. Shears. Alligator shears. Power presses. Milling machines. Power saws. Jointers. Portable power tools. Forming rolls and calenders. (d) Revolving...

17. VIEW OF THE FINAL STEP AT THE NO. 31 ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

17. VIEW OF THE FINAL STEP AT THE NO. 31 MILL; THE BRASS BARS ARE WOUND ONTO SPOOLS; THE AVERAGE OUTPUT PER HOUSE SHIFT WAS 200 TO 250 BARS. MOST OF THIS MATERIAL IS USED IN THE ELECTRICAL MANUFACTURING INDUSTRY FOR FUSES, BUS FARES, ELECTRICAL RELAYS, AND OTHER SUCH PRODUCTS. - American Brass Company, Kenosha Works, Hot Roll Mill, Kenosha, Kenosha County, WI

10. VIEW OF THE ADDITION TO BUILDING 883, REFERRED TO ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. VIEW OF THE ADDITION TO BUILDING 883, REFERRED TO AS SIDE C. ARMOR PLATE MADE WITH DEPLETED URANIUM WAS HEATED IN A MOLTEN SALT BATH, THEN PROCESSED THROUGH THE ROLLING MILL TO FORM LARGE SHEETS. (9/16/85) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

Discrete element method based scale-up model for material synthesis using ball milling

NASA Astrophysics Data System (ADS)

Santhanam, Priya Radhi

Mechanical milling is a widely used technique for powder processing in various areas. In this work, a scale-up model for describing this ball milling process is developed. The thesis is a combination of experimental and modeling efforts. Initially, Discrete Element Model (DEM) is used to describe energy transfer from milling tools to the milled powder for shaker, planetary, and attritor mills. The rolling and static friction coefficients are determined experimentally. Computations predict a quasisteady rate of energy dissipation, E d, for each experimental configuration. It is proposed that the milling dose defined as a product of Ed and milling time, t, divided by the mass of milled powder, mp characterizes the milling progress independently of the milling device or milling conditions used. Once the milling dose is determined for one experimental configuration, it can be used to predict the milling time required to prepare the same material in any milling configuration, for which Ed is calculated. The concept is validated experimentally for DEM describing planetary and shaker mills. For attritor, the predicted Ed includes substantial contribution from milling tool interaction events with abnormally high forces (>103 N). The energy in such events is likely dissipated to heat or plastically deform milling tools rather than refine material. Indeed, DEM predictions for the attritor correlate with experiments when such events are ignored in the analysis. With an objective of obtaining real-time indicators of milling progress, power, torque, and rotation speed of the impeller of an attritor mill are measured during preparation of metal matrix composite powders in the subsequent portion of this thesis. Two material systems are selected and comparisons made between in-situ parameters and experimental milling progress indicators. It is established that real-time measurements can certainly be used to describe milling progress. However, they need to be interpreted carefully depending on hardness of brittle component relative to milling media. To improve the DEM model of the attritor mill, it is desired to avoid the removal of unrealistic, high-force events using an approach that would not predict such events in the first place. It is observed that during experiments in attritor, balls may jam causing an increased resistance to the impeller's rotation. The impeller may instantaneously slow down, quickly returning to its pre-set rotation rate. Previous DEM models did not account for such rapid changes in the impeller's rotation. In this work, this relationship between impeller's torque and rotation rate is obtained experimentally and introduced in DEM. As a result, predicted Ed, are shown to correlate well with the experimental data. Finally, a methodology is proposed combining an experiment and its DEM description enabling one to identify the appropriate interaction parameters for powder systems. The experiment uses a miniature vibrating hopper and can be applied to characterize the powder flow for variety of materials. The hopper is designed to hold up to 20,000 particles of 50-mum diameter, which can be directly described in DEM. Based on comparison of discharge rate from experiments and model, all 6 interaction parameters were analyzed and the ideal conditions identified for Zirconia beads. The values of these parameters for powders are generally not the same as those established for macroscopic bodies. In addition, effects of some other experimental parameters such as particle size distribution and amplitude of vibration are also investigated.

STANDBY TOP AND BOTTOM ROTARY MILLING CUTTERS FOR TORIN LINE. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

STANDBY TOP AND BOTTOM ROTARY MILLING CUTTERS FOR TORIN LINE. SOME PRODUCT FROM THE #43 HOT ROLL IS PROCESSED ON THE TORIN LINE TO REMOVE OXIDIZED SURFACE MATERIAL. IN PRACTICE 15-20/1000 IS CUT FROM THE UPPER AND LOWER SURFACES OF THE STRIP AND RECYCLED TO THE CASTING SHOP. TORIN LINE ADDED AS PART OF 1981 EXPANSION PROGRAM. - American Brass Foundry, 70 Sayre Street, Buffalo, Erie County, NY

Application Of Numerical Modelling To Ribbed Wire Rod Dimensions Precision Increase

NASA Astrophysics Data System (ADS)

Szota, Piotr; Mróz, Sebastian; Stefanik, Andrzej

2007-05-01

The paper presents the results of theoretical and experimental investigations of the process of rolling square ribbed wire rod designed for concrete reinforcement. Numerical modelling of the process of rolling in the finishing and pre-finishing grooves was carried out using the Forge2005® software. In the investigation, particular consideration was given to the analysis of the effect of pre-finished band shape on the formation of ribs on the finished wire rod in the finishing groove. The results of theoretical studies were verified in experimental tests, which were carried out in a wire rolling mill.

29 CFR 1910.212 - General requirements for all machines.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Alligator shears. (d) Power presses. (e) Milling machines. (f) Power saws. (g) Jointers. (h) Portable power tools. (i) Forming rolls and calenders. (4) Barrels, containers, and drums. Revolving drums, barrels...

Nanostructured Mg 2Ni materials prepared by cold rolling and used as negative electrode for Ni-MH batteries

NASA Astrophysics Data System (ADS)

Pedneault, Sylvain; Huot, Jacques; Roué, Lionel

In the present work, cold rolling has been investigated as a new means of producing Mg-based metal hydrides for nickel-metal hydride (Ni-MH) batteries. Structure and electrochemical evolution of 2Mg-Ni cold-rolled samples were investigated as a function of the number of rolling passes as well as heat treatment. It was found that nanocrystalline Mg 2Ni alloy can be obtained by an appropriate three step process involving rolling, heat treatment and rolling again. It was shown that the number of primary and secondary rolling passes must be carefully optimized in order to favour the complete formation of Mg 2Ni alloy having a nanocrystalline structure (∼10 nm in crystallite size) without excessive sample oxidation. Actually, the best result was obtained by first rolling 90 times, followed by a heat treatment at 400 °C for 4 h and roll again 20 times. The resulting material displayed an initial discharge capacity of 205 mAh g -1, which is quite similar to that obtained with ball-milled Mg 2Ni alloy.

Microstructure Engineering in Hot Strip Mills, Part 1 of 2: Integrated mathematical Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

J.K. Brimacombe; I.V. Samaraseker; E.B. Hawbolt

1998-09-30

This report describes the work of developing an integrated model used to predict the thermal history, deformation, roll forces, microstructural evaluation and mechanical properties of steel strip in a hot-strip mill. This achievement results from a join research effort that is part of the American Iron and Steel Institute's (AISI) Advanced Process Control Program, a collaboration between the U.S. DOE and fifteen North American steel makers.

2. VIEW OF INTERIOR, EAST SIDE (SIDE A) OF BUILDING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. VIEW OF INTERIOR, EAST SIDE (SIDE A) OF BUILDING 883. INSTALLATION OF ROLLING MILLS AND MOLTEN SALT BATH EQUIPMENT FOR DEPLETED URANIUM FABRICATION. THE CRANE NEAR THE CEILING WAS USED TO INSTALL THE EQUIPMENT. BOXES ON THE FLOOR CONTAINED EQUIPMENT TO BE INSTALLED. (1/23/57) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

Defining rolled metal performance for cold bolt upsetting (bolt head)

NASA Astrophysics Data System (ADS)

Pachurin, G. V.; Shevchenko, S. M.; Filippov, A. A.; Mukhina, M. V.; Kuzmin, N. A.

2018-03-01

Hardware items are one of the products for mass consumption. Rolled metal for cold forging shall have the required ductility, uniform mechanical characteristics along the mill length, corresponding chemical composition and shall be free from internal or superficial defects. Standard mechanical characteristics have been reviewed in this document and fracture criteria of calibrated rolled steel 40X have been calculated after its isothermal treatment at different temperatures in nitre bath and subsequent drawing with different deformation degrees. Comparison of synergy fracture criteria showed that rolled stock, treated as per the proposed conditions: bath patenting at the temperature of 400°C and drawing with reduction rate of 5% and 10%, are more preferable, comparing to processing conditions, existing in the industry.

Neural and Neural Gray-Box Modeling for Entry Temperature Prediction in a Hot Strip Mill

NASA Astrophysics Data System (ADS)

Barrios, José Angel; Torres-Alvarado, Miguel; Cavazos, Alberto; Leduc, Luis

2011-10-01

In hot strip mills, initial controller set points have to be calculated before the steel bar enters the mill. Calculations rely on the good knowledge of rolling variables. Measurements are available only after the bar has entered the mill, and therefore they have to be estimated. Estimation of process variables, particularly that of temperature, is of crucial importance for the bar front section to fulfill quality requirements, and the same must be performed in the shortest possible time to preserve heat. Currently, temperature estimation is performed by physical modeling; however, it is highly affected by measurement uncertainties, variations in the incoming bar conditions, and final product changes. In order to overcome these problems, artificial intelligence techniques such as artificial neural networks and fuzzy logic have been proposed. In this article, neural network-based systems, including neural-based Gray-Box models, are applied to estimate scale breaker entry temperature, given its importance, and their performance is compared to that of the physical model used in plant. Several neural systems and several neural-based Gray-Box models are designed and tested with real data. Taking advantage of the flexibility of neural networks for input incorporation, several factors which are believed to have influence on the process are also tested. The systems proposed in this study were proven to have better performance indexes and hence better prediction capabilities than the physical models currently used in plant.

Production Engineering Program to Develop Improved Mass-Production Process for M42/M46 Grenade Bodies

DTIC Science & Technology

1978-03-01

J16 Photograph 3 Knurling Tool Installed in Machine . . ....... 16 Photograph 4 Shrapnel Pattern Being Knurled Into M42 Grenade Cylinder...body Fenn mill embossing rolls. Roehlen was awarded a cuxiu**L am’i labricated a knurling tool for use in the modified Tesker thread-rolling machine ...automatic grinding machine . IKratz-Wilde was not successful in developing tooling to produce domes to the inertia-welded assembly design. (See Figure

7. GENERAL VIEW OF PLANER AND SHIPPING COMPLEX FROM EAST ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. GENERAL VIEW OF PLANER AND SHIPPING COMPLEX FROM EAST END OF MAIN MILL BUILDING. NOTE TIMBER ROLL CASE AND BEAM HOIST IN FOREGROUND. - Hull-Oakes Lumber Company, 23837 Dawson Road, Monroe, Benton County, OR

Parametric Techniques for Multichannel Signal Processing.

DTIC Science & Technology

1985-10-01

AD-A165 649 PARAMETRIC TECHNIQUES FOR MULTICHANNEL SIGNAL PROCESSING(U) SYSTEM CONTROL TECHNOLOGY INC PALO RLTO CA B FRIEDLANDER OCT 85 5498-87 RRO...CONTRACT NO. DAAG29-83-C-0027 SYSTEMS CONTROL TECHNOLOGY, INC. DT1I? q4 1801 PAGE MILL ROAD ELI PALO ALTO, CALIFORNIA 94304EL C MAR 193 £4 APPROVED FOR...PROJECT, TASK Systems Control Technology, Inc. AREA & WORK UNIT NUMBERS 1801 Page Mill Road Palo Alto, CA 94304 II :ON?’ROLLING OFFICE NAME AND

LOOKING WEST FROM THE TOP OF THE WATER TOWER AT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

LOOKING WEST FROM THE TOP OF THE WATER TOWER AT ROOFTOPS OF INDUSTRIAL SHEDS. BUILDINGS IN THE FOREGROUND INCLUDE THE SHIPPING BAYS OF THE STRUCTURAL MILL AND MAIN ROLL SHOP. BUILDINGS IN THE MIDDLE GROUND INCLUDE PRESS SHOP NO. 2, CHIPPING YARD, BLACKSMITH SHOP, AND MACHINE SHOP NO. 1. THE TALLEST STRUCTURE IS THE VERTICAL FURNACE BUILDING, AND OPEN HEARTH NO. 5 IS IN THE EXTREME BACKGROUND. - U.S. Steel Homestead Works, Structural Mill, Along Monongahela River, Homestead, Allegheny County, PA

AISI/DOE Advanced Process Control Program Vol. 3 of 6 Microstructure Engineering in Hot Strip Mills, Part 1 of 2: Integrated Mathematical Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

J.K. Brimacombe; I.V. Samarasekera; E.B. Hawbolt

1999-07-31

This report describes the work of developing an integrated model used to predict the thermal history, deformation, roll forces, microstructural evolution and mechanical properties of steel strip in a hot-strip mill. This achievement results from a joint research effort that is part of the American Iron and Steel Institute's (AIS) Advanced Process Control Program, a collaboration between the U.S. DOE and fifteen North American Steelmakers.

View looking southwest at rollup ports of no. 1 billet ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View looking southwest at roll-up ports of no. 1 billet heating furnace for no. 1 seamless line. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

13. William E. Barrett, Photographer, August 1975. INTERIOR OF SAWMILL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. William E. Barrett, Photographer, August 1975. INTERIOR OF SAWMILL LOOKING EAST. LOGS FOR CENTER MILL ROLLED RIGHT TO CONVEYOR WHICH CARRIED THEM TO SECOND SLOPING DECK. - Meadow River Lumber Company, Highway 60, Rainelle, Greenbrier County, WV

An advanced dissymmetric rolling model for online regulation

NASA Astrophysics Data System (ADS)

Cao, Trong-Son

2017-10-01

Roll-bite model is employed to predict the rolling force, torque as well as to estimate the forward slip for preset or online regulation at industrial rolling mills. The rolling process is often dissymmetric in terms of work-rolls rotation speeds and diameters as well as the friction conditions at upper and lower contact surfaces between work-rolls and the strip. The roll-bite model thus must be able to account for these dissymmetries and in the same time has to be accurate and fast enough for online applications. In the present study, a new method, namely Adapted Discretization Slab Method (ADSM) is proposed to obtain a robust roll-bite model, which can take into account the aforementioned dissymmetries and has a very short response time, lower than one millisecond. This model is based on the slab method, with an adaptive discretization and a global Newton-Raphson procedure to improve the convergence speed. The model was validated by comparing with other dissymmetric models proposed in the literature, as well as Finite Element simulations and industrial pilot trials. Furthermore, back-calculation tool was also constructed for friction management for both offline and online applications. With very short CPU time, the ADSM-based model is thus attractive for all online applications, both for cold and hot rolling.

Accumulative Roll Bonding for Bladesmithing: From Book to Burrito to Blade

NASA Astrophysics Data System (ADS)

Hawgood, Mary; Hasier, John; Ho, Kathy

2016-12-01

A bladesmithing program was undertaken with the aim of producing superior decorative steel from dissimilar starting metals using severe plastic deformation. Accumulative roll bonding using an antiquated rolling mill was performed on 1095, CPM S30V, and 15N20 Hi-Contrast steel. Original attempts using the CPM S30V and the 1095 were unsuccessful, while later attempts using the 1095 and 15N20 Hi-Contrast steels produced a more desirable ingot. Characterization and testing, consisting of both optical and scanning electron microscopy, of the starting and wrought materials as well as the challenges in producing knife steel via synthesis of modern and traditional forging techniques, are discussed and failures analyzed.

Production, microstructure and mechanical properties of two different austenitic ODS steels

NASA Astrophysics Data System (ADS)

Gräning, T.; Rieth, M.; Hoffmann, J.; Möslang, A.

2017-04-01

This article is to summarize and examine processing parameters of novel developed austenitic oxide dispersed strengthened (ODS) steels. Comparing hot-rolled and extruded conditions after the same degree of deformation after and before annealing, are just some examples to give insights into the complex processing of austenitic ODS steels. One of the major drawbacks of the material is the more sophisticated production process. Due to a ductile matrix material with an increased stickiness during milling, a two-step milling procedure with the use of ZrO2 milling balls was applied to raise the production yield and to use the abrasion of the ZrO2 as an additional element to facilitate the formation of nano-sized precipitates. To get a better understanding how the different powder particle sizes after milling affect final properties, sieving was applied and revealed a serious effect in terms of precipitate size, distribution and mechanical properties. Grain sizes in relation to the precipitate size, annealing time and processing parameters were determined and compared to the mechanical properties. Hardness and tensile test have pointed out, that the precipitate size and number are more important in respect to the ultimate tensile strength than the grain size and that in this study hot-rolled material exhibited the better properties. The investigation of the microstructure illustrated the stability of precipitates during annealing at 1100 °C for 40 h. These heat treatments also led to a consistent grain size, due to the pinning effect of the grain boundaries, caused by precipitates.

Multi-stage FE simulation of hot ring rolling

NASA Astrophysics Data System (ADS)

Wang, C.; Geijselaers, H. J. M.; van den Boogaard, A. H.

2013-05-01

As a unique and important member of the metal forming family, ring rolling provides a cost effective process route to manufacture seamless rings. Applications of ring rolling cover a wide range of products in aerospace, automotive and civil engineering industries [1]. Above the recrystallization temperature of the material, hot ring rolling begins with the upsetting of the billet cut from raw stock. Next a punch pierces the hot upset billet to form a hole through the billet. This billet, referred to as preform, is then rolled by the ring rolling mill. For an accurate simulation of hot ring rolling, it is crucial to include the deformations, stresses and strains from the upsetting and piercing process as initial conditions for the rolling stage. In this work, multi-stage FE simulations of hot ring rolling process were performed by mapping the local deformation state of the workpiece from one step to the next one. The simulations of upsetting and piercing stages were carried out by 2D axisymmetric models using adaptive remeshing and element erosion. The workpiece for the ring rolling stage was subsequently obtained after performing a 2D to 3D mapping. The commercial FE package LS-DYNA was used for the study and user defined subroutines were implemented to complete the control algorithm. The simulation results were analyzed and also compared with those from the single-stage FE model of hot ring rolling.

17. Jet Lowe, Photographer, June 1978. FIVEROLL RUB DELIVERY ON ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

17. Jet Lowe, Photographer, June 1978. FIVE-ROLL RUB DELIVERY ON A. JENKS & SON FINISHER CARD; THE DELIVERY IS CONSISTENT WITH MANUFACTURE C. 1845-1855; FROM RIGHT FRONT OF OSCILLATING MECHANISM. - Watkins Mill, County Highway MM, Lawson, Ray County, MO

Roof structural system, similar in design to peaked roofs of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Roof structural system, similar in design to peaked roofs of rolling mill, yet note abandonment of phoenix columns for compression members. - Phoenix Iron Company, Girder Shop No. 6, North of French Creek, west of Gay Street, Phoenixville, Chester County, PA

Linking Grain Boundary Microstructure to Stress Corrosion Cracking of Cold Rolled Alloy 690 in PWR Primary Water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bruemmer, Stephen M.; Olszta, Matthew J.; Toloczko, Mychailo B.

2012-10-01

Grain boundary microstructures and microchemistries are examined in cold-rolled alloy 690 tubing and plate materials and comparisons are made to intergranular stress corrosion cracking (IGSCC) behavior in PWR primary water. Chromium carbide precipitation is found to be a key aspect for materials in both the mill annealed and thermally treated conditions. Cold rolling to high levels of reduction was discovered to produce small IG voids and cracked carbides in alloys with a high density of grain boundary carbides. The degree of permanent grain boundary damage from cold rolling was found to depend directly on the initial IG carbide distribution. Formore » the same degree of cold rolling, alloys with few IG precipitates exhibited much less permanent damage. Although this difference in grain boundary damage appears to correlate with measured SCC growth rates, crack tip examinations reveal that cracked carbides appeared to blunt propagation of IGSCC cracks in many cases. Preliminary results suggest that the localized grain boundary strains and stresses produced during cold rolling promote IGSCC susceptibility and not the cracked carbides and voids.« less

2. LOOKING WEST FROM THE TOP OF THE WATER TOWER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. LOOKING WEST FROM THE TOP OF THE WATER TOWER AT ROOFTOPS OF INDUSTRIAL SHEDS. BUILDINGS IN THE FOREGROUND INCLUDE THE SHIPPING BAYS OF THE STRUCTURAL MILL AND MAIN ROLL SHOP. BUILDINGS IN THE MIDDLE GROUND INCLUDE PRESS SHOP No. 2, CHIPPING YARD, BLACKSMITH SHOP, AND MACHINE SHOP No. 1. THE TALLEST STRUCTURE IS THE VERTICAL FURNACE BUILDING, AND OPEN HEARTH No. 5 IS IN THE EXTREME BACKGROUND. Jet Lowe, Photographer, 1989. - U.S. Steel Homestead Works, Structural Mill, Along Monongahela River, Homestead, Allegheny County, PA

Lipoid pneumonia caused by oil mist exposure from a steel rolling tandem mill

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cullen, M.R.; Balmes, J.R.; Robins, J.M.

1981-01-01

Five of nine active tandem mill operators exposed at work to aerosolized hydrocarbon mist were referred for evaluation of respiratory complaints. The worker with the longest exposure had reduced lung volumes; he was admitted to the hospital for detailed study. Exercise studies revealed work load limited by ventilation and arterial oxygen desaturation. Flexible fiberoptic bronchoscopy with bronchoalveolar lavage and transbronchial biopsy revealed evidence of lipoid pneumonia. Assessment of the mill revealed levels of respirable oil mist by personal samplers throughout the area far below the currently accepted standard of 5 mg/M3. These findings confirm a 20-year-old hypothesis of J.G. Jonesmore » regarding the hazard of oil mist in this industrial setting.« less

Experimental Comparison of Face-Milled and Face-Hobbed Spiral Bevel Gears

NASA Technical Reports Server (NTRS)

Handschuh, Robert F.; Nanlawala, Michael; Hawkins, John M.; Mahan, Danny

2001-01-01

An experimental comparison of face-milled and face-hobbed spiral bevel gears was accomplished. The two differently manufactured spiral bevel gear types were tested in a closed-loop facility at NASA Glenn Research Center. Strain, vibration, and noise testing were completed at various levels of rotational speed and load. Tests were conducted from static (slow-roll) to 12600 rpm and up to 269 N-m (2380 in.-lb) pinion speed and load conditions. The tests indicated that the maximum stress recorded at the root locations had nearly the same values, however the stress distribution was different from the toe to the heel. Also, the alternating stress measured was higher for the face-milled pinion than that attained for the face-hobbed pinion (larger minimum stress). The noise and vibration results indicated that the levels measured for the face-hobbed components were less than those attained for the face-milled gears tested.

Characterization of particle exposure in ferrochromium and stainless steel production.

PubMed

Järvelä, Merja; Huvinen, Markku; Viitanen, Anna-Kaisa; Kanerva, Tomi; Vanhala, Esa; Uitti, Jukka; Koivisto, Antti J; Junttila, Sakari; Luukkonen, Ritva; Tuomi, Timo

2016-07-01

This study describes workers' exposure to fine and ultrafine particles in the production chain of ferrochromium and stainless steel during sintering, ferrochromium smelting, stainless steel melting, and hot and cold rolling operations. Workers' personal exposure to inhalable dust was assessed using IOM sampler with a cellulose acetate filter (AAWP, diameter 25 mm; Millipore, Bedford, MA). Filter sampling methods were used to measure particle mass concentrations in fixed locations. Particle number concentrations and size distributions were examined using an SMPS+C sequential mobile particle sizer and counter (series 5.400, Grimm Aerosol Technik, Ainring, Germany), and a hand-held condensation particle counter (CPC, model 3007, TSI Incorporated, MN). The structure and elemental composition of particles were analyzed using TEM-EDXA (TEM: JEM-1220, JEOL, Tokyo, Japan; EDXA: Noran System Six, Thermo Fisher Scientific Inc., Madison,WI). Workers' personal exposure to inhalable dust averaged 1.87, 1.40, 2.34, 0.30, and 0.17 mg m(-3) in sintering plant, ferrochromium smelter, stainless steel melting shop, hot rolling mill, and the cold rolling mill, respectively. Particle number concentrations measured using SMPS+C varied from 58 × 10(3) to 662 × 10(3) cm(-3) in the production areas, whereas concentrations measured using SMPS+C and CPC3007 in control rooms ranged from 24 × 10(3) to 243 × 10(3) cm(-3) and 5.1 × 10(3) to 97 × 10(3) cm(-3), respectively. The elemental composition and the structure of particles in different production phases varied. In the cold-rolling mill non-process particles were abundant. In other sites, chromium and iron originating from ore and recycled steel scrap were the most common elements in the particles studied. Particle mass concentrations were at the same level as that reported earlier. However, particle number measurements showed a high amount of ultrafine particles, especially in sintering, alloy smelting and melting, and tapping operations. Particle number concentration and size distribution measurements provide important information regarding exposure to ultrafine particles, which cannot be seen in particle mass measurements.

Investigate feasibility of using ground penetrating radar in QC/QA of rubblization projects : executive summary report.

DOT National Transportation Integrated Search

2011-07-01

Rubblization and Roll (R/R) is an activity routinely practiced by the state DOTs for the rehabilitation of in-service composite pavements. The AC layer is milled and the exposed concrete pavement is broken (rubblized) into small fragments using heavy...

Space fabrication demonstration system

NASA Technical Reports Server (NTRS)

1978-01-01

The lower right aluminum beam cap roll forming mill was delivered and installed in the beam builder. The beam was brought to full operational status and beams of one to six bay lengths were produced to demonstrate full system capability. Although the cap flange waviness problem persists, work is progressing within cost and schedule.

West Europe Report, No. 2223.

DTIC Science & Technology

1983-10-24

to rolling mill No 28 would report to the new jobs assigned to them by the management. Following this meeting the minister of industry himself...municipal borders. As a matter of fact, it was not so much a predominantly political-military interest which motivated his zeal, but prima- rily the new jobs with

Assessment of flat rolling theories for the use in a model-based controller for high-precision rolling applications

NASA Astrophysics Data System (ADS)

Stockert, Sven; Wehr, Matthias; Lohmar, Johannes; Abel, Dirk; Hirt, Gerhard

2017-10-01

In the electrical and medical industries the trend towards further miniaturization of devices is accompanied by the demand for smaller manufacturing tolerances. Such industries use a plentitude of small and narrow cold rolled metal strips with high thickness accuracy. Conventional rolling mills can hardly achieve further improvement of these tolerances. However, a model-based controller in combination with an additional piezoelectric actuator for high dynamic roll adjustment is expected to enable the production of the required metal strips with a thickness tolerance of +/-1 µm. The model-based controller has to be based on a rolling theory which can describe the rolling process very accurately. Additionally, the required computing time has to be low in order to predict the rolling process in real-time. In this work, four rolling theories from literature with different levels of complexity are tested for their suitability for the predictive controller. Rolling theories of von Kármán, Siebel, Bland & Ford and Alexander are implemented in Matlab and afterwards transferred to the real-time computer used for the controller. The prediction accuracy of these theories is validated using rolling trials with different thickness reduction and a comparison to the calculated results. Furthermore, the required computing time on the real-time computer is measured. Adequate results according the prediction accuracy can be achieved with the rolling theories developed by Bland & Ford and Alexander. A comparison of the computing time of those two theories reveals that Alexander's theory exceeds the sample rate of 1 kHz of the real-time computer.

Enhancing wear resistance of working bodies of grinder through lining crushed material

NASA Astrophysics Data System (ADS)

Romanovich, A. A.; Annenko, D. M.; Romanovich, M. A.; Apukhtina, I. V.

2018-03-01

The article presents the analysis of directions of increasing wear resistance of working surfaces of rolls. A technical solution developed at the level of the invention is proposed, which is simple to implement in production conditions and which makes it possible to protect the roll surface from heavy wear due to surfacing of wear-resistant mesh material, cells of which are filling with grinding material in the process of work. Retaining them enables one to protect the roll surface from wear. The paper dwells on conditions of pressing materials in cells of eccentric rolls on the working surface with a grid of rectangular shape. The paper presents an equation for calculation of the cell dimension that provides the lining of the working surface by a mill material with respect to its properties. The article presents results of comparative studies on the grinding process of a press roller grinder (PRG) between rolls with and without a fusion-bonded mesh. It is clarified that the lining of rolls working surface slightly reduces the quality of the grinding, since the material thickness in the cell is small and has a finely divided and compacted structure with high strength.

Nanoporous Al sandwich foils using size effect of Al layer thickness during Cu/Al/Cu laminate rolling

NASA Astrophysics Data System (ADS)

Yu, Hailiang; Lu, Cheng; Tieu, A. Kiet; Li, Huijun; Godbole, Ajit; Kong, Charlie

2018-06-01

The roll bonding technique is one of the most widely used methods to produce metal laminate sheets. Such sheets offer interesting research opportunities for both scientists and engineers. In this paper, we report on an experimental investigation of the 'thickness effect' during laminate rolling for the first time. Using a four-high multifunction rolling mill, Cu/Al/Cu laminate sheets were fabricated with a range of thicknesses (16, 40, 70 and 130 μm) of the Al layer. The thickness of the Cu sheets was a constant 300 μm. After rolling, TEM images show good bonding quality between the Cu and Al layers. However, there are many nanoscale pores in the Al layer. The fraction of nanoscale pores in the Al layer increases with a reduction in the Al layer thickness. The finite element method was used to simulate the Cu/Al/Cu rolling process. The simulation results reveal the effect of the Al layer thickness on the deformation characteristics of the Cu/Al/Cu laminate. Finally, we propose that the size effect of the Al layer thickness during Cu/Al/Cu laminate rolling may offer a method to fabricate 'nanoporous' Al sandwich laminate foils. Such foils can be used in electromagnetic shielding of electrical devices and noisy shielding of building.

Microstructure and Mechanical Properties in Hot-Rolled Extra High-Yield-Strength Steel Plates for Offshore Structure and Shipbuilding

NASA Astrophysics Data System (ADS)

Liu, Dongsheng; Li, Qingliang; Emi, Toshihiko

2011-05-01

Key parameters for a thermomechanically controlled processing and accelerated cooling process (TMCP-AcC) were determined for integrated mass production to produce extra high-yield-strength microalloyed low carbon SiMnCrNiCu steel plates for offshore structure and bulk shipbuilding. Confocal scanning microscopy was used to make in-situ observations on the austenite grain growth during reheating. A Gleeble 3800 thermomechanical simulator was employed to investigate the flow stress behavior, static recrystallization (SRX) of austenite, and decomposition behavior of the TMCP conditioned austenite during continuous cooling. The Kocks-Mecking model was employed to describe the constitutive behavior, while the Johnson-Mehl-Avrami-Kolmogorov (JMAK) approach was used to predict the SRX kinetics. The effects of hot rolling schedule and AcC on microstructure and properties were investigated by test-scale rolling trials. The bridging between the laboratory observations and the process parameter determination to optimize the mass production was made by integrated industrial production trials on a set of a 5-m heavy plate mill equipped with an accelerated cooling system. Successful production of 60- and 50-mm-thick plates with yield strength in excess of 460 MPa and excellent toughness at low temperature (213 K (-60 °C)) in the parent metal and the simulated coarse-grained heat affected zone (CGHAZ) provides a useful integrated database for developing advanced high-strength steel plates via TMCP-AcC.

A KPI-based process monitoring and fault detection framework for large-scale processes.

PubMed

Zhang, Kai; Shardt, Yuri A W; Chen, Zhiwen; Yang, Xu; Ding, Steven X; Peng, Kaixiang

2017-05-01

Large-scale processes, consisting of multiple interconnected subprocesses, are commonly encountered in industrial systems, whose performance needs to be determined. A common approach to this problem is to use a key performance indicator (KPI)-based approach. However, the different KPI-based approaches are not developed with a coherent and consistent framework. Thus, this paper proposes a framework for KPI-based process monitoring and fault detection (PM-FD) for large-scale industrial processes, which considers the static and dynamic relationships between process and KPI variables. For the static case, a least squares-based approach is developed that provides an explicit link with least-squares regression, which gives better performance than partial least squares. For the dynamic case, using the kernel representation of each subprocess, an instrument variable is used to reduce the dynamic case to the static case. This framework is applied to the TE benchmark process and the hot strip mill rolling process. The results show that the proposed method can detect faults better than previous methods. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Determination of rational parameters for process of grinding materials pre-crushed by pressure in ball mill

NASA Astrophysics Data System (ADS)

Romanovich, A. A.; Romanovich, L. G.; Chekhovskoy, E. I.

2018-03-01

The article presents the results of experimental studies on the grinding process of a clinker preliminarily ground in press roller mills in a ball mill equipped with energy exchange devices. The authors studied the influence of the coefficients of loading for grinding bodies of the first and second mill chambers, their lengths, angles of inclination, and the mutual location of energy exchange devices (the ellipse segment and the double-acting blade) on the output parameters of the grinding process (productivity, drive power consumption and specific energy consumption). It is clarified that the best results of the disaggregation and grinding process, judging by the minimum specific energy consumption in the grinding of clinker with an anisotropic texture after force deformation between the rolls of a press roller shredder, are achieved at a certain angle of ellipse segment inclination; the length of the first chamber and the coefficients of loading the chambers with grinding bodies.

Solid-phase fermentation and juice expression systems for sweet sorghum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bryan, W.L.; Monroe, G.E.; Caussariel, P.M.

1985-01-01

Two systems to recover fermented juice from variety M 81E sweet sorghum stalks that contained about 11% fermentable sugar were compared. (a) Stalks with leaves and tops removed were chopped and inoculated with 0.2% yeast in a forage harvester, stored under anaerobic conditions for 75 hours in insulated fermentors and pressed in a screw press to recover fermented juice (5-6% ethanol). (b) Mechanically harvested sweet sorghum billets (30 cm length) without leaves or seed heads were shredded and milled in a 3-roll mill; and bagasse was inoculated with 0.2% yeast, fermented for 100 h and pressed to recover fermented juicemore » (4 to 5% ethanol). Potential ethanol yields were 75% of theoretical for the forage harvest system and 78% for the shredder mill system, based on 95% of theoretical ethanol yield from juice expressed during milling and no loss of ethanol during fermentation, handling and pressing in the screw press. 20 references.« less

Study on anaerobic treatment of hazardous steel-mill waste rolling oil (SmWRO) for multi-benefit disposal route.

PubMed

Ma, Huanhuan; Li, Zifu; Yin, Fubin; Kao, William; Yin, Yi; Bai, Xiaofeng

2014-01-01

Steel-mill waste rolling oil (SmWRO) is considered as hazardous substance with high treatment and disposal fees. Anaerobic process could not only transform the hazardous substance into activated sludge, but also generate valuable biogas. This study aimed at studying the biochemical methane potential of SmWRO under inoculum to substrate VS ratios (ISRs) of 0.25, 0.5, 1, 1.5, 2 and 3 using septic tank sludge as inoculum in mesophilic and thermophilic conditions, with blank tests for control. Specific biogas yield (mL/g VS(added)), net biogas yield (mL/g VS(removed)) and VS removal were analyzed. The ANOVA results indicated great influence of ISR and temperature on studied parameters. ISR of 1.5 at 55°C and ISR of 1.5 and 2 at 35°C were suggested with the highest specific biogas yield (262-265 and 303mL/g VS(added)). Kinetic analysis showed that Gompertz model fit the experimental data best with the least RMSE and largest R(2). Copyright © 2013 Elsevier Ltd. All rights reserved.

Testing of Face-milled Spiral Bevel Gears at High-speed and Load

NASA Technical Reports Server (NTRS)

Handschuh, Robert F.

2001-01-01

Spiral bevel gears are an important drive system components of rotorcraft (helicopters) currently in use. In this application the spiral bevel gears are required to transmit very high torque at high rotational speed. Available experimental data on the operational characteristics for thermal and structural behavior is relatively small in comparison to that found for parallel axis gears. An ongoing test program has been in place at NASA Glenn Research Center over the last ten years to investigate their operational behavior at operating conditions found in aerospace applications. This paper will summarize the results of the tests conducted on face-milled spiral bevel gears. The data from the pinion member (temperature and stress) were taken at conditions from slow-roll to 14400 rpm and up to 537 kW (720 hp). The results have shown that operating temperature is affected by the location of the lubricating jet with respect to the point it is injected and the operating conditions that are imposed. Also the stress measured from slow-roll to very high rotational speed, at various torque levels, indicated little dynamic affect over the rotational speeds tested.

Rolling element fatigue testing of gear materials

NASA Technical Reports Server (NTRS)

Nahm, A. H.

1978-01-01

Rolling element fatigue lives of nine alloys were evaluated in Rolling Contact (RC) rigs. Test conditions included a Hertzian stress at 4,826 MPa (700 ksi), a rolling speed of 6.23 m/sec (245 in/sec.). Tests were run with a Type I oil (MIL-L-7808G) at room temperature. B-10 lives (10% failure rate) of alloys were compared versus reference alloys, VIM-VAR AISI M-50 and VAR AISI 9310. Six case carburizing alloys (AISI 9310, CBS600, CBS1000M, EX00014, Vasco X-2 and EX00053) and three through-hardening alloys (AISI M-50, VascoMax 350 and Vasco Matrix 2 evaluated, showed RCF performance inferior or equivalent to that of AISI 9310 and AISI M-50. It was also found that the effects of vacuum melting processes, different tempering temperatures, freezing cycle during heat treating, shot peening, gold plating and chrome plating employed in the present investigation did not significantly affect RCF life.

The MillSOT-A Spiral Orbit Tribometer on a Milling Machine

NASA Technical Reports Server (NTRS)

Pepper, Stephen V.

2014-01-01

A spiral orbit tribometer (SOT) intended to characterize friction and wear phenomena has been constructed on a milling machine. The instrument, essentially a retainerless thrust bearing with one ball and flat races, is exceedingly simple and inexpensive to construct. The capabilities of the tribometer to measure both the coefficient of friction and contact electrical resistance are demonstrated with clean specimens as well as with well known lubricants such as molybdenum disulphide and Krytox oil. Operation in a purged environment of inert gas is also demonstrated. The results with these lubricants are quite close to what is obtained by other methods. Suggestions for extending the capabilities of the tribometer are given. This arrangement may find use in university mechanical engineering laboratories to introduce and study rolling contact motion as well as for research in contact mechanics and tribology.

Research and Development of Heavy Gauge X80 Pipeline Plate Utilizing Optimized Rolling and Cooling Process

NASA Astrophysics Data System (ADS)

Li, Shaopo; Li, Jiading; Ding, Wenhua; Zhang, Hai

This paper reports on the experience with the production of 27/33 mm X80 heavy wall thicknesses, large OD (48") in Shouqin Steel Co., Ltd. (SQS). Considering the technology capability of the plate mill in SQS, a optimized rolling and cooling process was developed to achieve stable heavy gauge X80 mechanical properties. The importance of the slab reheating process and rolling schedule will be discussed in the paper. In addition, the per pass reductions logic used during recrystallized rough rolling, and special emphasis on the reduction of the final roughing pass prior to the intermediate holding resulting in a fine uniform prior austenite microstructure will be discussed. The optimized cooling process application after finish rolling guarantees the steady control of the final bainitic microstructure with optimum M/A phase for heavy gauge X80 plates. The plates produced by this process achieved good flatness and excellent mechanical properties. SQS has produced 10000 tons 27mm X80 for the Middle Asia C Line Project and 1000 tons 33mm X80 for the 3rd West-to-East Natural Gas Transmission Pipeline Project in 2013-2014. The products utilizing optimized rolling and cooling process showed extremely excellent low temperature toughness.

Replacement Packing for 37MM Antitank Gun Recoil

DTIC Science & Technology

2008-04-01

Parts Per Hundred Rubber (PPHR) NBR -07-GRS-01 Paracril AJ Nitrile Rubber 100.00 Zinc Oxide 5.00 Stearic Acid 1.00 AC) 617 Polyethylene 2.00 (DQ...3 Figure 4. Nitrile rubber compound being produced on rolling mill. ..............................................5 Figure 5. The two...9 List of Tables Table 1. Composition and properties of Nitrile rubber ...................................................................4

The reaction of boric acid with wood in a polystyrene matrix

Treesearch

Yanxin Wang; John Simonsen; Carlos Pascoal Neto; Joao Rocha; Timothy G. Rials; Eric Hart

1996-01-01

The reaction of boric acid with wood fibers in a polymer melt was examined using 13C-nuclear magnetic resonance (NMR), 11B-NMR. differential scanning calorimetry, dynamic mechanical analysis, and component extraction and by the determination of material properties. Samples were blended at 350 and 380°F in a roll mill. The...

70. DETAIL OF TRACTION CABLE ENGAGEMENT DEVICE. SMALL, KNOBBED LEVER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

70. DETAIL OF TRACTION CABLE ENGAGEMENT DEVICE. SMALL, KNOBBED LEVER ON BUCKET HANGER WAS PULLED DOWN BY A CAMEL (FIXED CAM RAIL AT CENTER) AS BUCKET ROLLED PAST IT, CAUSING A CLAMP TO CLOSE AGAINST TRACTION CABLE. A SIMILAR CAMEL (NO LONGER EXTANT) DISENGAGED CLAMP ON RECEIVING SIDE. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

Effect of Solution Annealing on Susceptibility to Intercrystalline Corrosion of Stainless Steel with 20% Cr and 8% Ni

NASA Astrophysics Data System (ADS)

Taiwade, R. V.; Patil, A. P.; Patre, S. J.; Dayal, R. K.

2013-06-01

In general, as-received (AR) austenitic stainless steels (ASSs) contain complex carbide precipitates due to manufacturing operations, subsequent annealing treatment, or due to the fabrication processes such as welding. The presence of pre-existing carbides leads to cumulative sensitization and make the steel susceptible to intercrystalline corrosion (ICC)/intergranular corrosion (IGC) which causes premature failure during service. Solution annealing (SA) is one of the ways to deal with such situations. In this present investigation, the AR (hot rolled and mill annealed) chromium-nickel (Cr-Ni) ASS is compared with SA Cr-Ni ASS. The extent of ICC/IGC was evaluated qualitatively and quantitatively by various electrochemical tests including ASTM standard A-262 Practice A and Practice E, double loop electrochemical potentiokinetic reactivation and electrochemical impedance spectroscopy. The degree of sensitization for hot rolled mill annealed AR condition is found to be substantially higher (51.55%) than that of SA condition (26.9%) for thermally aged samples (at 700 °C). The chemical composition across the grain boundary was measured using electron probe micro-analyzer for both (AR and SA) conditions and confirms that the pre-sensitization effect was completely removed after SA treatment.

Rolling-element fatigue life with two synthetic cycloaliphatic traction fluids

NASA Technical Reports Server (NTRS)

Loewenthal, S. H.; Parker, R. J.

1976-01-01

The life potential of two synthetic cycloaliphatic hydrocarbon traction fluids in rolling element fatigue was evaluated in a five ball fatigue tester. Life comparisons with a MIL-L-23699 qualified tetraester oil showed that the traction test oils had good fatigue life performance, comparable to that of the tetraester oil. No statistically significant life differences between the traction fluids and the tetraester oil were exhibited under the accelerated fatigue test conditions. Erratic operating behavior was occasionally encountered during tests with the antiwear additive containing traction fluid for reasons thought to be related to excessive chemical activity under high contact pressure. This behavior occasionally resulted in premature test termination due to excessive surface distress and overheating.

Scale-up of organic reactions in ball mills: process intensification with regard to energy efficiency and economy of scale.

PubMed

Stolle, Achim; Schmidt, Robert; Jacob, Katharina

2014-01-01

The scale-up of the Knoevenagel-condensation between vanillin and barbituric acid carried out in planetary ball mills is investigated from an engineering perspective. Generally, the reaction proceeded in the solid state without intermediate melting and afforded selectively only one product. The reaction has been used as a model to analyze the influence and relationship of different parameters related to operation in planetary ball mills. From the viewpoint of technological parameters the milling ball diameter, dMB, the filling degree with respect to the milling balls' packing, ΦMB,packing, and the filling degree of the substrates with respect to the void volume of the milling balls' packing, ΦGS, have been investigated at different reaction scales. It was found that milling balls with small dMB lead to higher yields within shorter reaction time, treaction, or lower rotation frequency, rpm. Thus, the lower limit is set considering the technology which is available for the separation of the milling balls from the product after the reaction. Regarding ΦMB,packing, results indicate that the optimal value is roughly 50% of the total milling beakers' volume, VB,total, independent of the reaction scale or reaction conditions. Thus, 30% of VB,total are taken by the milling balls. Increase of the initial batch sizes changes ΦGS significantly. However, within the investigated parameter range no negative influence on the yield was observed. Up to 50% of VB,total can be taken over by the substrates in addition to 30% for the total milling ball volume. Scale-up factors of 15 and 11 were realized considering the amount of substrates and the reactor volume, respectively. Beside technological parameters, variables which influence the process itself, treaction and rpm, were investigated also. Variation of those allowed to fine-tune the reaction conditions in order to maximize the yield and minimize the energy intensity.

Rolling-Element Fatigue Testing and Data Analysis - A Tutorial

NASA Technical Reports Server (NTRS)

Vlcek, Brian L.; Zaretsky, Erwin V.

2011-01-01

In order to rank bearing materials, lubricants and other design variables using rolling-element bench type fatigue testing of bearing components and full-scale rolling-element bearing tests, the investigator needs to be cognizant of the variables that affect rolling-element fatigue life and be able to maintain and control them within an acceptable experimental tolerance. Once these variables are controlled, the number of tests and the test conditions must be specified to assure reasonable statistical certainty of the final results. There is a reasonable correlation between the results from elemental test rigs with those results obtained with full-scale bearings. Using the statistical methods of W. Weibull and L. Johnson, the minimum number of tests required can be determined. This paper brings together and discusses the technical aspects of rolling-element fatigue testing and data analysis as well as making recommendations to assure quality and reliable testing of rolling-element specimens and full-scale rolling-element bearings.

A model for investigating the influence of road surface texture and tyre tread pattern on rolling resistance

NASA Astrophysics Data System (ADS)

Hoever, Carsten; Kropp, Wolfgang

2015-09-01

The reduction of rolling resistance is essential for a more environmentally friendly road transportation sector. Both tyre and road design can be utilised to reduce rolling resistance. In both cases a reliable simulation tool is needed which is able to quantify the influence of design parameters on the rolling resistance of a tyre rolling on a specific road surface. In this work a previously developed tyre/road interaction model is extended to account for different tread patterns and for losses due to small-scale tread deformation. Calculated contact forces and tyre vibrations for tyre/road interaction under steady-state rolling are used to predict rolling losses in the tyre. Rolling resistance is calculated for a series of different tyre/road combinations. Results are compared with rolling resistance measurements. The agreement between simulations and measurements is generally very good. It is found that both the tyre structure and small-scale tread deformations contribute to the rolling losses. The small-scale contribution depends mainly on the road roughness profile. The mean profile depth of the road surface is identified to correlate very well with the rolling resistance. Additional calculations are performed for non-traditional rubberised road surfaces, however, with mixed results. This possibly indicates the existence of additional loss mechanisms for these surfaces.

JPRS Report, Soviet Union, Kommunist, No. 7, May 1987

DTIC Science & Technology

1987-08-13

to the Editors Party Work and Education (V. Shirshov) 50 Scientific Research Institute or Design Bureau? (Yu. Belyayev) 52 The Artist and... research institutes are actual design or technological bureaus judging by the nature of their work and the qualifications of their personnel. In...bureaus while rolling mills or construction machinery are designed by scientific research institutes? This lowers the responsibility of the

High-rate, roll-to-roll nanomanufacturing of flexible systems

NASA Astrophysics Data System (ADS)

Cooper, Khershed P.; Wachter, Ralph F.

2012-10-01

Since the National Nanotechnology Initiative was first announced in 2000, nanotechnology has developed an impressive catalog of nano-scale structures with building-blocks such as nanoparticles, nanotubes, nanorods, nanopillars, and quantum dots. Similarly, there are accompanying materials processes such as, atomic layer deposition, pulsed layer deposition, nanoprinting, nanoimprinting, transfer printing, nanolithography and nanopatterning. One of the challenges of nanomanufacturing is scaling up these processes reliably and affordably. Roll-to-roll manufacturing is a means for scaling up, for increasing throughput. It is high-speed production using a continuous, moving platform such as a web or a flexible substrate. The adoption of roll-to-roll to nanomanufacturing is novel. The goal is to build structures and devices with nano-scale features and specific functionality. The substrate could be a polymer, metal foil, silk, cloth or paper. The materials to build the structures and multi-level devices could be organic, inorganic or biological. Processing could be solution-based, e.g., ink-jet printing, or vacuum-based, e.g., chemical vapor deposition. Products could be electronics, optoelectronics, membranes, catalysts, microfluidics, lab-on-film, filters, etc. By this means, processing of large and conformal areas is achievable. High-throughput translates into low cost, which is the attraction of roll-to-roll nanomanufacturing. There are technical challenges requiring fundamental scientific advances in materials and process development and in manufacturing and system-integration where achieving nano-scale feature size, resolution and accuracy at high speeds can be major hurdles. We will give an overview of roll-to-roll nanomanufacturing with emphasis on the need to understand the material, process and system complexities, the need for instrumentation, measurement, and process control and describe the concept of cyber-enabled nanomanufacturing for reliable and predictable production.

Crystallization of high-strength nano-scale leucite glass-ceramics.

PubMed

Theocharopoulos, A; Chen, X; Wilson, R M; Hill, R; Cattell, M J

2013-11-01

Fine-grained, high strength, translucent leucite dental glass-ceramics are synthesized via controlled crystallization of finely milled glass powders. The objectives of this study were to utilize high speed planetary milling of an aluminosilicate glass for controlled surface crystallization of nano-scale leucite glass-ceramics and to test the biaxial flexural strength. An aluminosilicate glass was synthesized, attritor or planetary milled and heat-treated. Glasses and glass-ceramics were characterized using particle size analysis, X-ray diffraction and scanning electron microscopy. Experimental (fine and nanoscale) and commercial (Ceramco-3, IPS Empress Esthetic) leucite glass-ceramics were tested using the biaxial flexural strength (BFS) test. Gaussian and Weibull statistics were applied. Experimental planetary milled glass-ceramics showed an increased leucite crystal number and nano-scale median crystal sizes (0.048-0.055 μm(2)) as a result of glass particle size reduction and heat treatments. Experimental materials had significantly (p<0.05) higher mean BFS and characteristic strength values than the commercial materials. Attritor milled and planetary milled (2h) materials showed no significant (p>0.05) strength difference. All other groups' mean BFS and characteristic strengths were found to be significantly different (p<0.05) to each other. The mean (SD) MPa strengths measured were: Attritor milled: 252.4 (38.7), Planetary milled: 225.4 (41.8) [4h milling] 255.0 (35.0) [2h milling], Ceramco-3: 75.7 (6.8) and IPS Empress: 165.5 (30.6). Planetary milling enabled synthesis of nano-scale leucite glass-ceramics with high flexural strength. These materials may help to reduce problems associated with brittle fracture of all-ceramic restorations and give reduced enamel wear. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Study on the deterioration origin of thermomechanical contact fatigue

NASA Astrophysics Data System (ADS)

Tudose-Sandu-Ville, O. F.

2016-08-01

Thermomechanical wear is a complex phenomenon present in a number of industrial domains, such as rolling bearings, gears, friction wheels, rolling mill rollers. In this type of surface tribological deterioration, both fundamental and some peculiar wears are combined (abrasive, adhesive, corrosive wear and contact fatigue), with mechanical ant thermal causes. The present paper takes into account the contact fatigue type of deterioration, with both causes in mechanical variable load and the thermal tide action on the contact surface. There are some theories synthetically presented regarding the location of critical stresses in rolling contact fatigue. The Jacq thermal effect is briefly presented with some considerations concerning the temperature gradient in the metallic wall. The connection between the Jacq thermal anomaly and the thermomechanical contact fatigue is considered to be a new approach. Also, the same location for both mechanical and thermal critical stresses gives a strong support for the thermomechanical contact fatigue primary deterioration, according to the results obtained during the author's PhD research.

Early Fault Diagnosis of Bearings Using an Improved Spectral Kurtosis by Maximum Correlated Kurtosis Deconvolution

PubMed Central

Jia, Feng; Lei, Yaguo; Shan, Hongkai; Lin, Jing

2015-01-01

The early fault characteristics of rolling element bearings carried by vibration signals are quite weak because the signals are generally masked by heavy background noise. To extract the weak fault characteristics of bearings from the signals, an improved spectral kurtosis (SK) method is proposed based on maximum correlated kurtosis deconvolution (MCKD). The proposed method combines the ability of MCKD in indicating the periodic fault transients and the ability of SK in locating these transients in the frequency domain. A simulation signal overwhelmed by heavy noise is used to demonstrate the effectiveness of the proposed method. The results show that MCKD is beneficial to clarify the periodic impulse components of the bearing signals, and the method is able to detect the resonant frequency band of the signal and extract its fault characteristic frequency. Through analyzing actual vibration signals collected from wind turbines and hot strip rolling mills, we confirm that by using the proposed method, it is possible to extract fault characteristics and diagnose early faults of rolling element bearings. Based on the comparisons with the SK method, it is verified that the proposed method is more suitable to diagnose early faults of rolling element bearings. PMID:26610501

Rolling element bearing defect diagnosis under variable speed operation through angle synchronous averaging of wavelet de-noised estimate

NASA Astrophysics Data System (ADS)

Mishra, C.; Samantaray, A. K.; Chakraborty, G.

2016-05-01

Rolling element bearings are widely used in rotating machines and their faults can lead to excessive vibration levels and/or complete seizure of the machine. Under special operating conditions such as non-uniform or low speed shaft rotation, the available fault diagnosis methods cannot be applied for bearing fault diagnosis with full confidence. Fault symptoms in such operating conditions cannot be easily extracted through usual measurement and signal processing techniques. A typical example is a bearing in heavy rolling mill with variable load and disturbance from other sources. In extremely slow speed operation, variation in speed due to speed controller transients or external disturbances (e.g., varying load) can be relatively high. To account for speed variation, instantaneous angular position instead of time is used as the base variable of signals for signal processing purposes. Even with time synchronous averaging (TSA) and well-established methods like envelope order analysis, rolling element faults in rolling element bearings cannot be easily identified during such operating conditions. In this article we propose to use order tracking on the envelope of the wavelet de-noised estimate of the short-duration angle synchronous averaged signal to diagnose faults in rolling element bearing operating under the stated special conditions. The proposed four-stage sequential signal processing method eliminates uncorrelated content, avoids signal smearing and exposes only the fault frequencies and its harmonics in the spectrum. We use experimental data1

Space Fabrication Demonstration System

NASA Technical Reports Server (NTRS)

1978-01-01

Progress in the mechanical/structural assembly of the beam builder is reported. The following structures were investigated: cross brace magazine/dispenser subsystem; and rolling mill supply reel, guide, and drive. The fabrication facility design and a detail design of all major subsystem components are discussed. The number of spot welds per structural joint were reduced which enables the doubling of length of truss which can be produced within known electrode life limits.

Mathematical Modeling of the Effect of Roll Diameter on the Thermo-Mechanical Behavior of Twin Roll Cast AZ31 Magnesium Alloy Strips

NASA Astrophysics Data System (ADS)

Hadadzadeh, Amir; Wells, Mary

Although the Twin Roll Casting (TRC) process has been used in the aluminum sheet production industry for more than 60 years, the usage of this process to fabricate magnesium sheets is still at its early stages. Similar to other manufacturing processes, the development of the TRC process for magnesium alloys has followed a typical route of preliminary studies using a laboratory-scale facility, followed by pilot-scale testing and most recently attempting to use an industrial-scale twin roll caster. A powerful tool to understand and quantify the trends of the processing conditions and effects of scaling up from a laboratory size TRC machine to an industrial scale one is develop a mathematical model of the process. This can elucidate the coupled fluid-thermo-mechanical behavior of the cast strip during the solidification and then deformation stages of the process. In the present study a Thermal-Fluid-Stress model has been developed for TRC of AZ31 magnesium alloy for three roll diameters by employing the FEM commercial package ALSIM. The roll diameters were chosen as 355mm, 600mm and 1150mm. The effect of casting speed for each diameter was studied in terms of fluid flow, thermal history and stress-strain evolution in the cast strip in the roll bite region.

Multilength Scale Patterning of Functional Layers by Roll-to-Roll Ultraviolet-Light-Assisted Nanoimprint Lithography.

PubMed

Leitgeb, Markus; Nees, Dieter; Ruttloff, Stephan; Palfinger, Ursula; Götz, Johannes; Liska, Robert; Belegratis, Maria R; Stadlober, Barbara

2016-05-24

Top-down fabrication of nanostructures with high throughput is still a challenge. We demonstrate the fast (>10 m/min) and continuous fabrication of multilength scale structures by roll-to-roll UV-nanoimprint lithography on a 250 mm wide web. The large-area nanopatterning is enabled by a multicomponent UV-curable resist system (JRcure) with viscous, mechanical, and surface properties that are tunable over a wide range to either allow for usage as polymer stamp material or as imprint resist. The adjustable elasticity and surface chemistry of the resist system enable multistep self-replication of structured resist layers. Decisive for defect-free UV-nanoimprinting in roll-to-roll is the minimization of the surface energies of stamp and resist, and the stepwise reduction of the stiffness from one layer to the next is essential for optimizing the reproduction fidelity especially for nanoscale features. Accordingly, we demonstrate the continuous replication of 3D nanostructures and the high-throughput fabrication of multilength scale resist structures resulting in flexible polyethylenetherephtalate film rolls with superhydrophobic properties. Moreover, a water-soluble UV-imprint resist (JRlift) is introduced that enables residue-free nanoimprinting in roll-to-roll. Thereby we could demonstrate high-throughput fabrication of metallic patterns with only 200 nm line width.

On-Line Flatness Measurement in the Steelmaking Industry

PubMed Central

Molleda, Julio; Usamentiaga, Rubén; Garcίa, Daniel F.

2013-01-01

Shape is a key characteristic to determine the quality of outgoing flat-rolled products in the steel industry. It is greatly influenced by flatness, a feature to describe how the surface of a rolled product approaches a plane. Flatness is of the utmost importance in steelmaking, since it is used by most downstream processes and customers for the acceptance or rejection of rolled products. Flatness sensors compute flatness measurements based on comparing the length of several longitudinal fibers of the surface of the product under inspection. Two main different approaches are commonly used. On the one hand, most mechanical sensors measure the tensile stress across the width of the rolled product, while manufacturing and estimating the fiber lengths from this stress. On the other hand, optical sensors measure the length of the fibers by means of light patterns projected onto the product surface. In this paper, we review the techniques and the main sensors used in the steelmaking industry to measure and quantify flatness defects in steel plates, sheets and strips. Most of these techniques and sensors can be used in other industries involving rolling mills or continuous production lines, such as aluminum, copper and paper, to name a few. Encompassed in the special issue, State-of-the-Art Sensors Technology in Spain 2013, this paper also reviews the most important flatness sensors designed and developed for the steelmaking industry in Spain. PMID:23939583

On-line flatness measurement in the steelmaking industry.

PubMed

Molleda, Julio; Usamentiaga, Rubén; García, Daniel F

2013-08-09

Shape is a key characteristic to determine the quality of outgoing flat-rolled products in the steel industry. It is greatly influenced by flatness, a feature to describe how the surface of a rolled product approaches a plane. Flatness is of the utmost importance in steelmaking, since it is used by most downstream processes and customers for the acceptance or rejection of rolled products. Flatness sensors compute flatness measurements based on comparing the length of several longitudinal fibers of the surface of the product under inspection. Two main different approaches are commonly used. On the one hand, most mechanical sensors measure the tensile stress across the width of the rolled product, while manufacturing and estimating the fiber lengths from this stress. On the other hand, optical sensors measure the length of the fibers by means of light patterns projected onto the product surface. In this paper, we review the techniques and the main sensors used in the steelmaking industry to measure and quantify flatness defects in steel plates, sheets and strips. Most of these techniques and sensors can be used in other industries involving rolling mills or continuous production lines, such as aluminum, copper and paper, to name a few. Encompassed in the special issue, State-of-the-Art Sensors Technology in Spain 2013, this paper also reviews the most important flatness sensors designed and developed for the steelmaking industry in Spain.

Influence of mill scale and rust layer on the corrosion resistance of low-alloy steel in simulated concrete pore solution

NASA Astrophysics Data System (ADS)

Shi, Jin-jie; Ming, Jing

2017-01-01

Electrochemical impedance spectroscopy, cyclic potentiodynamic polarization measurements, and scanning electron microscopy in conjunction with energy-dispersive X-ray spectroscopy were used to investigate the influence of mill scale and rust layer on the passivation capability and chloride-induced corrosion behaviors of conventional low-carbon (LC) steel and low-alloy (LA) steel in simulated concrete pore solution. The results show that mill scale exerts different influences on the corrosion resistance of both steels at various electrochemical stages. We propose that the high long-term corrosion resistance of LA steel is mainly achieved through the synergistic effect of a gradually formed compact, adherent and well-distributed Cr-enriched inner rust layer and the physical barrier protection effect of mill scale.

24. The DryingRoom in the coating mill at Lawrence, Mass. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

24. The Drying-Room in the coating mill at Lawrence, Mass. After the paper has received its coating from the coating-machine shown in the previous picture, it passes in a continuous web to the drying-room. Blasts of hot air coming out of galvanized ducts beneath support it for a distance of 100 feet, until it reaches the drying-chamber in the rear of the room. Here it hangs in festoons much like those of cotton cloth shown on page 219. In the picture the paper is passing from right to left. After leaving the drying-room it is wound on rolls, as shown in the next picture. (p.238.) - Champion-International Paper Company, West bank of Spicket River at Canal Street, Lawrence, Essex County, MA

Temperature Evolution During Plane Strain Compression Of Tertiary Oxide Scale On Steel

NASA Astrophysics Data System (ADS)

Suarez, L.; Vanden Eynde, X.; Lamberigts, M.; Houbaert, Y.

2007-04-01

An oxide scale layer always forms at the steel surface during hot rolling. This scale layer separates the work roll from the metal substrate. Understanding the deformation behaviour and mechanical properties of the scale is of great interest because it affects the frictional conditions during hot rolling and the heat-transfer behaviour at the strip-roll interface. A thin wustite scale layer (<20 μm) was created under controlled conditions in an original laboratory device adequately positioned in a compression testing machine to investigate plane strain compression. Oxidation tests were performed on an ULC steel grade. After the oxide growth at 1050°C, plane strain compression (PSC) was performed immediately to simulate the hot rolling process. PSC experiments were performed at a deformation temperature of 1050°C, with reduction ratios from 5 to 70%, and strain rates of 10s-1 under controlled gas atmospheres. Results show that for wustite, ductility is obvious at 1050°C. Even after deformation oxide layers exhibit good adhesion to the substrate and homogeneity over the thickness. The tool/sample temperature difference seems to be the reason for the unexpected ductile behaviour of the scale layer.

High-Throughput Printing Process for Flexible Electronics

NASA Astrophysics Data System (ADS)

Hyun, Woo Jin

Printed electronics is an emerging field for manufacturing electronic devices with low cost and minimal material waste for a variety of applications including displays, distributed sensing, smart packaging, and energy management. Moreover, its compatibility with roll-to-roll production formats and flexible substrates is desirable for continuous, high-throughput production of flexible electronics. Despite the promise, however, the roll-to-roll production of printed electronics is quite challenging due to web movement hindering accurate ink registration and high-fidelity printing. In this talk, I will present a promising strategy for roll-to-roll production using a novel printing process that we term SCALE (Self-aligned Capillarity-Assisted Lithography for Electronics). By utilizing capillarity of liquid inks on nano/micro-structured substrates, the SCALE process facilitates high-resolution and self-aligned patterning of electrically functional inks with greatly improved printing tolerance. I will show the fabrication of key building blocks (e.g. transistor, resistor, capacitor) for electronic circuits using the SCALE process on plastics.

Effect of roll compaction on granule size distribution of microcrystalline cellulose–mannitol mixtures: computational intelligence modeling and parametric analysis

PubMed Central

Kazemi, Pezhman; Khalid, Mohammad Hassan; Pérez Gago, Ana; Kleinebudde, Peter; Jachowicz, Renata; Szlęk, Jakub; Mendyk, Aleksander

2017-01-01

Dry granulation using roll compaction is a typical unit operation for producing solid dosage forms in the pharmaceutical industry. Dry granulation is commonly used if the powder mixture is sensitive to heat and moisture and has poor flow properties. The output of roll compaction is compacted ribbons that exhibit different properties based on the adjusted process parameters. These ribbons are then milled into granules and finally compressed into tablets. The properties of the ribbons directly affect the granule size distribution (GSD) and the quality of final products; thus, it is imperative to study the effect of roll compaction process parameters on GSD. The understanding of how the roll compactor process parameters and material properties interact with each other will allow accurate control of the process, leading to the implementation of quality by design practices. Computational intelligence (CI) methods have a great potential for being used within the scope of quality by design approach. The main objective of this study was to show how the computational intelligence techniques can be useful to predict the GSD by using different process conditions of roll compaction and material properties. Different techniques such as multiple linear regression, artificial neural networks, random forest, Cubist and k-nearest neighbors algorithm assisted by sevenfold cross-validation were used to present generalized models for the prediction of GSD based on roll compaction process setting and material properties. The normalized root-mean-squared error and the coefficient of determination (R2) were used for model assessment. The best fit was obtained by Cubist model (normalized root-mean-squared error =3.22%, R2=0.95). Based on the results, it was confirmed that the material properties (true density) followed by compaction force have the most significant effect on GSD. PMID:28176905

Effect of roll compaction on granule size distribution of microcrystalline cellulose-mannitol mixtures: computational intelligence modeling and parametric analysis.

PubMed

Kazemi, Pezhman; Khalid, Mohammad Hassan; Pérez Gago, Ana; Kleinebudde, Peter; Jachowicz, Renata; Szlęk, Jakub; Mendyk, Aleksander

2017-01-01

Dry granulation using roll compaction is a typical unit operation for producing solid dosage forms in the pharmaceutical industry. Dry granulation is commonly used if the powder mixture is sensitive to heat and moisture and has poor flow properties. The output of roll compaction is compacted ribbons that exhibit different properties based on the adjusted process parameters. These ribbons are then milled into granules and finally compressed into tablets. The properties of the ribbons directly affect the granule size distribution (GSD) and the quality of final products; thus, it is imperative to study the effect of roll compaction process parameters on GSD. The understanding of how the roll compactor process parameters and material properties interact with each other will allow accurate control of the process, leading to the implementation of quality by design practices. Computational intelligence (CI) methods have a great potential for being used within the scope of quality by design approach. The main objective of this study was to show how the computational intelligence techniques can be useful to predict the GSD by using different process conditions of roll compaction and material properties. Different techniques such as multiple linear regression, artificial neural networks, random forest, Cubist and k-nearest neighbors algorithm assisted by sevenfold cross-validation were used to present generalized models for the prediction of GSD based on roll compaction process setting and material properties. The normalized root-mean-squared error and the coefficient of determination ( R 2 ) were used for model assessment. The best fit was obtained by Cubist model (normalized root-mean-squared error =3.22%, R 2 =0.95). Based on the results, it was confirmed that the material properties (true density) followed by compaction force have the most significant effect on GSD.

Ring rolling process simulation for geometry optimization

NASA Astrophysics Data System (ADS)

Franchi, Rodolfo; Del Prete, Antonio; Donatiello, Iolanda; Calabrese, Maurizio

2017-10-01

Ring Rolling is a complex hot forming process where different rolls are involved in the production of seamless rings. Since each roll must be independently controlled, different speed laws must be set; usually, in the industrial environment, a milling curve is introduced to monitor the shape of the workpiece during the deformation in order to ensure the correct ring production. In the present paper a ring rolling process has been studied and optimized in order to obtain anular components to be used in aerospace applications. In particular, the influence of process input parameters (feed rate of the mandrel and angular speed of main roll) on geometrical features of the final ring has been evaluated. For this purpose, a three-dimensional finite element model for HRR (Hot Ring Rolling) has been implemented in SFTC DEFORM V11. The FEM model has been used to formulate a proper optimization problem. The optimization procedure has been implemented in the commercial software DS ISight in order to find the combination of process parameters which allows to minimize the percentage error of each obtained dimension with respect to its nominal value. The software allows to find the relationship between input and output parameters applying Response Surface Methodology (RSM), by using the exact values of output parameters in the control points of the design space explored through FEM simulation. Once this relationship is known, the values of the output parameters can be calculated for each combination of the input parameters. After the calculation of the response surfaces for the selected output parameters, an optimization procedure based on Genetic Algorithms has been applied. At the end, the error between each obtained dimension and its nominal value has been minimized. The constraints imposed were the maximum values of standard deviations of the dimensions obtained for the final ring.

Towards roll-to-roll fabrication of electronics, optics, and optoelectronics for smart and intelligent packaging

NASA Astrophysics Data System (ADS)

Kololuoma, Terho K.; Tuomikoski, Markus; Makela, Tapio; Heilmann, Jali; Haring, Tomi; Kallioinen, Jani; Hagberg, Juha; Kettunen, Ilkka; Kopola, Harri K.

2004-06-01

Embedding of optoelectrical, optical, and electrical functionalities into low-cost products like packages and printed matter can be used to increase their information content. These functionalities make also possible the realization of new type of entertaining, impressive or guiding effects on the product packages and printed matter. For these purposes, components like displays, photodetectors, light sources, solar cells, battery elements, diffractive optical elements, lightguides, electrical conductors, resistors, transistors, switching elements etc. and their integration to functional modules are required. Additionally, the price of the components for low-end products has to be in cent scale or preferably below that. Therefore, new, cost-effective, and volume scale capable manufacturing techniques are required. Recent developments of liquid-phase processable electrical and optical polymeric, inorganic, and hybrid materials - inks - have made it possible to fabricate functional electrical, optical and optoelectrical components by conventional roll-to-roll techniques such as gravure printing, embossing, digital printing, offset, and screen printing on flexible paper and plastic like substrates. In this paper, we show our current achievements in the field of roll-to-roll fabricated, optics, electronics and optoelectronics. With few examples, we also demonstrate the printing and hot-embossing capabilities of table scale printing machines and VTT Electronic's 'PICO' roll-to-roll pilot production facility.

Evaluation of rice husk ash as filler in tread compounds

NASA Astrophysics Data System (ADS)

Fernandes, M. R. S.; Furtado, C. R. G.; de Sousa, A. M. F.

2014-05-01

Rice which is one of the largest agriculture crops produces around 22% of rice rusk during its milling process. This material is mainly used as fuel for energy generation, which results in an ash, which disposal represents an environmental issue. The rice husk ash (RHA) contains over than 70% of silica in an amorphous form and a lot of applications is being developed for it all over the world. The use of silica as a filler in the tire industry is growing since it contributes significantly to the reduction of fuel consumption of the automobiles, allowing at the same time better traction (safety). This paper presents an evaluation of the use of RHA as filler in rubber tread compounds prepared in lab scale and compares its performance with compounds prepared with commercial silica and carbon black, the fillers normally used in tire industry. Mechanical and rheological properties are evaluated, with emphasis for tan delta as an indicator of tread performance related with rolling resistance (fuel consumption) and wet grip/traction (safety).

Discrete Element Method Simulations of the Inter-Particle Contact Parameters for the Mono-Sized Iron Ore Particles.

PubMed

Li, Tongqing; Peng, Yuxing; Zhu, Zhencai; Zou, Shengyong; Yin, Zixin

2017-05-11

Aiming at predicting what happens in reality inside mills, the contact parameters of iron ore particles for discrete element method (DEM) simulations should be determined accurately. To allow the irregular shape to be accurately determined, the sphere clump method was employed in modelling the particle shape. The inter-particle contact parameters were systematically altered whilst the contact parameters between the particle and wall were arbitrarily assumed, in order to purely assess its impact on the angle of repose for the mono-sized iron ore particles. Results show that varying the restitution coefficient over the range considered does not lead to any obvious difference in the angle of repose, but the angle of repose has strong sensitivity to the rolling/static friction coefficient. The impacts of the rolling/static friction coefficient on the angle of repose are interrelated, and increasing the inter-particle rolling/static friction coefficient can evidently increase the angle of repose. However, the impact of the static friction coefficient is more profound than that of the rolling friction coefficient. Finally, a predictive equation is established and a very close agreement between the predicted and simulated angle of repose is attained. This predictive equation can enormously shorten the inter-particle contact parameters calibration time that can help in the implementation of DEM simulations.

Tensor to scalar ratio and large scale power suppression from pre-slow roll initial conditions

NASA Astrophysics Data System (ADS)

Lello, Louis; Boyanovsky, Daniel

2014-05-01

We study the corrections to the power spectra of curvature and tensor perturbations and the tensor-to-scalar ratio r in single field slow roll inflation with standard kinetic term due to initial conditions imprinted by a ``fast-roll'' stage prior to slow roll. For a wide range of initial inflaton kinetic energy, this stage lasts only a few e-folds and merges smoothly with slow-roll thereby leading to non-Bunch-Davies initial conditions for modes that exit the Hubble radius during slow roll. We describe a program that yields the dynamics in the fast-roll stage while matching to the slow roll stage in a manner that is independent of the inflationary potentials. Corrections to the power spectra are encoded in a ``transfer function'' for initial conditions Script Tα(k), Script Pα(k) = PBDα(k)Script Tα(k), implying a modification of the ``consistency condition'' for the tensor to scalar ratio at a pivot scale k0: r(k0) = -8nT(k0) [Script TT(k0)/Script TScript R(k0)]. We obtain Script Tα(k) to leading order in a Born approximation valid for modes of observational relevance today. A fit yields Script Tα(k) = 1+Aαk-pcos [2πωk/Hsr+varphiα], with 1.5lesssimplesssim2, ω simeq 1 and Hsr the Hubble scale during slow roll inflation, where curvature and tensor perturbations feature the same p,ω for a wide range of initial conditions. These corrections lead to both a suppression of the quadrupole and oscillatory features in both PR(k) and r(k0) with a period of the order of the Hubble scale during slow roll inflation. The results are quite general and independent of the specific inflationary potentials, depending solely on the ratio of kinetic to potential energy κ and the slow roll parameters epsilonV, ηV to leading order in slow roll. For a wide range of κ and the values of epsilonV ηV corresponding to the upper bounds from Planck, we find that the low quadrupole is consistent with the results from Planck, and the oscillations in r(k0) as a function of k0 could be observable if the modes corresponding to the quadrupole and the pivot scale crossed the Hubble radius very few (2-3) e-folds after the onset of slow roll. We comment on possible impact on the recent BICEP2 results.

Effect of the Leveling Conditions on Residual Stress Evolution of Hot Rolled High Strength Steels for Cold Forming

NASA Astrophysics Data System (ADS)

Park, Keecheol; Oh, Kyungsuk

2017-09-01

In order to investigate the effect of leveling conditions on residual stress evolution during the leveling process of hot rolled high strength steels, the in-plane residual stresses of sheet processed under controlled conditions at skin-pass mill and levelers were measured by cutting method. The residual stress was localized near the edge of sheet. As the thickness of sheet was increased, the residual stress occurred region was expanded. The magnitude of residual stress within the sheet was reduced as increasing the deformation occurred during the leveling process. But the residual stress itself was not removed completely. The magnitude of camber occurred at cut plate was able to be predicted by the residual stress distribution. A numerical algorithm was developed for analysing the effect of leveling conditions on residual stress. It was able to implement the effect of plastic deformation in leveling, tension, work roll bending, and initial state of sheet (residual stress and curl distribution). The validity of simulated results was verified from comparison with the experimentally measured residual stress and curl in a sheet.

Effect of Temperature on the Storage Life of Polysulfide Sealants

DTIC Science & Technology

1989-01-01

University of Adelaide, South Australia. After two and a half years of experience in Rubber Technology with the Olympic Tyre and Rubber Company, Melbourne...he joined the rubber section of MRL in November 1970. Since 1975 he has been involved in R & D work in the sealant section as an Experimental Officer...repeatedly passing the mixture through a triple roll mill. One set of the calcium carbonate-solvent series was enclosed in a heat sealed wrapping of

Getting the Policies Right: The Prioritization and Sequencing of Policies in Post-Conflict Countries

DTIC Science & Technology

2007-01-01

be recapitulated again using public money. Similarly, liberalization of cashew nuts , which was imposed by the World Bank and the IMF, did not go...reduced from 105 % to 35 % in 1996 and to 30 percent in 1999; however liberalization of cashew nuts didn’t go well. Mixed success Infrastructure and...owned enterprises. Although many of the enterprises were small, the three cement plants, two breweries, the steel rolling mill, the cashew

Approximation of Viscoelastic Stresses from Newtonian Turbulent Kinematics

DTIC Science & Technology

1988-09-01

birefringence of polyethylene oxide solutions in a four roll mill. J.Poly.Sci.:Poly.Phys.Ed. 14, 1111-1119. Dandridge, A., Meeten , G.H., Layec-Raphalen, M.N...flows. Poly. Comm. 25, 144-146. Metzner, A.B., & Astarita, G . 1967 External flow of viscoelastic materials: fluid property restrictions on the use of...dumbbell model for dilute solutions. Rheol.Acta 23, 151-162. Philippoff, W. 1956 Flow-birefringence and stress. Nature 178 , 811-812. Ryskin, G . 1987a

Just enough inflation: power spectrum modifications at large scales

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cicoli, Michele; Downes, Sean; Dutta, Bhaskar

2014-12-01

We show that models of 'just enough' inflation, where the slow-roll evolution lasted only 50- 60 e-foldings, feature modifications of the CMB power spectrum at large angular scales. We perform a systematic analytic analysis in the limit of a sudden transition between any possible non-slow-roll background evolution and the final stage of slow-roll inflation. We find a high degree of universality since most common backgrounds like fast-roll evolution, matter or radiation-dominance give rise to a power loss at large angular scales and a peak together with an oscillatory behaviour at scales around the value of the Hubble parameter at themore » beginning of slow-roll inflation. Depending on the value of the equation of state parameter, different pre-inflationary epochs lead instead to an enhancement of power at low ℓ, and so seem disfavoured by recent observational hints for a lack of CMB power at ℓ∼< 40. We also comment on the importance of initial conditions and the possibility to have multiple pre-inflationary stages.« less

Processing of oats and the impact of processing operations on nutrition and health benefits.

PubMed

Decker, Eric A; Rose, Devin J; Stewart, Derek

2014-10-01

Oats are a uniquely nutritious food as they contain an excellent lipid profile and high amounts of soluble fibre. However, an oat kernel is largely non-digestible and thus must be utilised in milled form to reap its nutritional benefits. Milling is made up of numerous steps, the most important being dehulling to expose the digestible groat, heat processing to inactivate enzymes that cause rancidity, and cutting, rolling or grinding to convert the groat into a product that can be used directly in oatmeal or can be used as a food ingredient in products such as bread, ready-to-eat breakfast cereals and snack bars. Oats can also be processed into oat bran and fibre to obtain high-fibre-containing fractions that can be used in a variety of food products.

Large Scale Triboelectric Nanogenerator and Self-Powered Pressure Sensor Array Using Low Cost Roll-to-Roll UV Embossing

PubMed Central

Dhakar, Lokesh; Gudla, Sudeep; Shan, Xuechuan; Wang, Zhiping; Tay, Francis Eng Hock; Heng, Chun-Huat; Lee, Chengkuo

2016-01-01

Triboelectric nanogenerators (TENGs) have emerged as a potential solution for mechanical energy harvesting over conventional mechanisms such as piezoelectric and electromagnetic, due to easy fabrication, high efficiency and wider choice of materials. Traditional fabrication techniques used to realize TENGs involve plasma etching, soft lithography and nanoparticle deposition for higher performance. But lack of truly scalable fabrication processes still remains a critical challenge and bottleneck in the path of bringing TENGs to commercial production. In this paper, we demonstrate fabrication of large scale triboelectric nanogenerator (LS-TENG) using roll-to-roll ultraviolet embossing to pattern polyethylene terephthalate sheets. These LS-TENGs can be used to harvest energy from human motion and vehicle motion from embedded devices in floors and roads, respectively. LS-TENG generated a power density of 62.5 mW m−2. Using roll-to-roll processing technique, we also demonstrate a large scale triboelectric pressure sensor array with pressure detection sensitivity of 1.33 V kPa−1. The large scale pressure sensor array has applications in self-powered motion tracking, posture monitoring and electronic skin applications. This work demonstrates scalable fabrication of TENGs and self-powered pressure sensor arrays, which will lead to extremely low cost and bring them closer to commercial production. PMID:26905285

Tube manufacturing and characterization of oxide dispersion strengthened ferritic steels

NASA Astrophysics Data System (ADS)

Ukai, Shigeharu; Mizuta, Shunji; Yoshitake, Tunemitsu; Okuda, Takanari; Fujiwara, Masayuki; Hagi, Shigeki; Kobayashi, Toshimi

2000-12-01

Oxide dispersion strengthened (ODS) ferritic steels have an advantage in radiation resistance and superior creep rupture strength at elevated temperature due to finely distributed Y2O3 particles in the ferritic matrix. Using a basic composition of low activation ferritic steel (Fe-12Cr-2W-0.05C), cladding tube manufacturing by means of pilger mill rolling and subsequent recrystallization heat-treatment was conducted while varying titanium and yttria contents. The recrystallization heat-treatment, to soften the tubes hardened due to cold-rolling and to subsequently improve the degraded mechanical properties, was demonstrated to be effective in the course of tube manufacturing. For a titanium content of 0.3 wt% and yttria of 0.25 wt%, improvement of the creep rupture strength can be attained for the manufactured cladding tubes. The ductility is also adequately maintained.

Sharp inflaton potentials and bi-spectra: effects of smoothening the discontinuity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martin, Jérôme; Sriramkumar, L.; Hazra, Dhiraj Kumar, E-mail: jmartin@iap.fr, E-mail: sriram@physics.iitm.ac.in, E-mail: dhiraj@apctp.org

Sharp shapes in the inflaton potentials often lead to short departures from slow roll which, in turn, result in deviations from scale invariance in the scalar power spectrum. Typically, in such situations, the scalar power spectrum exhibits a burst of features associated with modes that leave the Hubble radius either immediately before or during the epoch of fast roll. Moreover, one also finds that the power spectrum turns scale invariant at smaller scales corresponding to modes that leave the Hubble radius at later stages, when slow roll has been restored. In other words, the imprints of brief departures from slowmore » roll, arising out of sharp shapes in the inflaton potential, are usually of a finite width in the scalar power spectrum. Intuitively, one may imagine that the scalar bi-spectrum too may exhibit a similar behavior, i.e. a restoration of scale invariance at small scales, when slow roll has been reestablished. However, in the case of the Starobinsky model (viz. the model described by a linear inflaton potential with a sudden change in its slope) involving the canonical scalar field, it has been found that, a rather sharp, though short, departure from slow roll can leave a lasting and significant imprint on the bi-spectrum. The bi-spectrum in this case is found to grow linearly with the wavenumber at small scales, a behavior which is clearly unphysical. In this work, we study the effects of smoothening the discontinuity in the Starobinsky model on the scalar bi-spectrum. Focusing on the equilateral limit, we analytically show that, for smoother potentials, the bi-spectrum indeed turns scale invariant at suitably large wavenumbers. We also confirm the analytical results numerically using our newly developed code BINGO. We conclude with a few comments on certain related points.« less

Implementation and verification of a four-probe motion error measurement system for a large-scale roll lathe used in hybrid manufacturing

NASA Astrophysics Data System (ADS)

Chen, Yuan-Liu; Niu, Zengyuan; Matsuura, Daiki; Lee, Jung Chul; Shimizu, Yuki; Gao, Wei; Oh, Jeong Seok; Park, Chun Hong

2017-10-01

In this paper, a four-probe measurement system is implemented and verified for the carriage slide motion error measurement of a large-scale roll lathe used in hybrid manufacturing where a laser machining probe and a diamond cutting tool are placed on two sides of a roll workpiece for manufacturing. The motion error of the carriage slide of the roll lathe is composed of two straightness motion error components and two parallelism motion error components in the vertical and horizontal planes. Four displacement measurement probes, which are mounted on the carriage slide with respect to four opposing sides of the roll workpiece, are employed for the measurement. Firstly, based on the reversal technique, the four probes are moved by the carriage slide to scan the roll workpiece before and after a 180-degree rotation of the roll workpiece. Taking into consideration the fact that the machining accuracy of the lathe is influenced by not only the carriage slide motion error but also the gravity deformation of the large-scale roll workpiece due to its heavy weight, the vertical motion error is thus characterized relating to the deformed axis of the roll workpiece. The horizontal straightness motion error can also be synchronously obtained based on the reversal technique. In addition, based on an error separation algorithm, the vertical and horizontal parallelism motion error components are identified by scanning the rotating roll workpiece at the start and the end positions of the carriage slide, respectively. The feasibility and reliability of the proposed motion error measurement system are demonstrated by the experimental results and the measurement uncertainty analysis.

Engineer Design of a Mono-Mooring System.

DTIC Science & Technology

1966-01-01

swivels . When asked whether the bogie rails were machined by a large radius boring mill , Mr. Coombe indicated that these rails are rolled then V welded...lifted aboard the transp ort vessel , the disposi- tion of the various system compo- nents shall be as follows: 1. Buoy shall be complete , with...tugboat , equipped with towing winch or pow9r capstan , LOA 110 ’ — 120’, twin screw; BHP-l000 minimum . 7. It has been assumed that weld- ing machines

Characterization of Used MIL-L-7808 Lubricants.

DTIC Science & Technology

1985-05-01

Gravimetric Finish 20 2.3.3 Separation of Mineral Oil by means of Sulphuric Acid 21 2.3.4 Rolls-Royce Method 1032 26 2.3.5 Conclusion 26 3 Minimum...and STM No. 1 i Application of Sulphuric Acid Method for MOC to:- IV Standards based upon ATL.9100 23 V Standards based upon ATL.9101 24 VI Standards...total acid numbers of the standards before, and after application of each technique. Considering firstly the volatile contaminant contents obtained by STM

Simulation of the bimetal cast in the case of milling rolls

NASA Astrophysics Data System (ADS)

Mihut, G.; Popa, E.

2015-06-01

In the paper it is proposed, in main, to obtain of a model of numerical simulation, valid general and applicable the whole peculiars cases of bimetal casting, model with which help can be studied through the computer, the optimization possibility of flowing working condition of liquid alloy of the distribution of temperatures field, of the liquid phase and contraction during the solidification, with the minimum price (necessary reimbursement of the software and calculus equipment) in very short time etc.

Production of ultra-thin nano-scaled graphene platelets from meso-carbon micro-beads

DOEpatents

Zhamu, Aruna; Guo, Jiusheng; Jang, Bor Z

2014-11-11

A method of producing nano-scaled graphene platelets (NGPs) having an average thickness no greater than 50 nm, typically less than 2 nm, and, in many cases, no greater than 1 nm. The method comprises (a) intercalating a supply of meso-carbon microbeads (MCMBs) to produce intercalated MCMBs; and (b) exfoliating the intercalated MCMBs at a temperature and a pressure for a sufficient period of time to produce the desired NGPs. Optionally, the exfoliated product may be subjected to a mechanical shearing treatment, such as air milling, air jet milling, ball milling, pressurized fluid milling, rotating-blade grinding, or ultrasonicating. The NGPs are excellent reinforcement fillers for a range of matrix materials to produce nanocomposites. Nano-scaled graphene platelets are much lower-cost alternatives to carbon nano-tubes or carbon nano-fibers.

Removal of millimeter-scale rolled edges using bevel-cut-like tool influence function in magnetorheological jet polishing.

PubMed

Yang, Hao; Cheng, Haobo; Feng, Yunpeng; Jing, Xiaoli

2018-05-01

Subaperture polishing techniques usually produce rolled edges due to edge effect. The rolled edges, especially those in millimeter scale on small components, are difficult to eliminate using conventional polishing methods. Magnetorheological jet polishing (MJP) offers the possibility of the removal of these structures, owing to its small tool influence function (TIF) size. Hence, we investigate the removal characters of inclined MJP jetting models by means of computational fluid dynamics (CFD) simulations and polishing experiments. A discrete phase model (DPM) is introduced in the simulation to get the influence of abrasive particle concentration on the removal mechanism. Therefore, a more accurate model for MJP removal mechanisms is built. With several critical problems solved, a small bevel-cut-like TIF (B-TIF), which has fine acentric and unimodal characteristics, is obtained through inclined jetting. The B-TIF proves to have little edge effect and is applied in surface polishing of thin rolled edges. Finally, the RMS of the experimental section profile converges from 10.5 nm to 1.4 nm, and the rolled edges are successfully suppressed. Consequently, it is validated that the B-TIF has remarkable ability in the removal of millimeter-scale rolled edges.

Impact of vertical wind shear on roll structure in idealized hurricane boundary layers

NASA Astrophysics Data System (ADS)

Wang, Shouping; Jiang, Qingfang

2017-03-01

Quasi-two-dimensional roll vortices are frequently observed in hurricane boundary layers. It is believed that this highly coherent structure, likely caused by the inflection-point instability, plays an important role in organizing turbulent transport. Large-eddy simulations are conducted to investigate the impact of wind shear characteristics, such as the shear strength and inflection-point level, on the roll structure in terms of its spectral characteristics and turbulence organization. A mean wind nudging approach is used in the simulations to maintain the specified mean wind shear without directly affecting turbulent motions. Enhancing the radial wind shear expands the roll horizontal scale and strengthens the roll's kinetic energy. Increasing the inflection-point level tends to produce a narrow and sharp peak in the power spectrum at the wavelength consistent with the roll spacing indicated by the instantaneous turbulent fields. The spectral tangential momentum flux, in particular, reaches a strong peak value at the roll wavelength. In contrast, the spectral radial momentum flux obtains its maximum at the wavelength that is usually shorter than the roll's, suggesting that the roll radial momentum transport is less efficient than the tangential because of the quasi-two-dimensionality of the roll structure. The most robust rolls are produced in a simulation with the highest inflection-point level and relatively strong radial wind shear. Based on the spectral analysis, the roll-scale contribution to the turbulent momentum flux can reach 40 % in the middle of the boundary layer.

Product Recovery From Hemlock "Pulpwood" From Alaska.

Treesearch

Thomas D. Fahey

1983-01-01

A total of 363 western hemlock (Tsuga heterophylla (Raf.) Sarg.) logs from Alaska were sawn to compare recovery at a stud mill and at a dimension mill. Recovery at both mills varied by log diameters and by log scaling system. Lumber grade recovery was primarily in Stud grade at the stud mill and in Standard and Construction grade at the dimension...

The effects of processing techniques on magnesium-based composite

NASA Astrophysics Data System (ADS)

Rodzi, Siti Nur Hazwani Mohamad; Zuhailawati, Hussain

2016-12-01

The aim of this study is to investigate the effect of processing techniques on the densification, hardness and compressive strength of Mg alloy and Mg-based composite for biomaterial application. The control sample (pure Mg) and Mg-based composite (Mg-Zn/HAp) were fabricated through mechanical alloying process using high energy planetary mill, whilst another Mg-Zn/HAp composite was fabricated through double step processing (the matrix Mg-Zn alloy was fabricated by planetary mill, subsequently HAp was dispersed by roll mill). As-milled powder was then consolidated by cold press into 10 mm diameter pellet under 400 MPa compaction pressure before being sintered at 300 °C for 1 hour under the flow of argon. The densification of the sintered pellets were then determined by Archimedes principle. Mechanical properties of the sintered pellets were characterized by microhardness and compression test. The results show that the density of the pellets was significantly increased by addition of HAp, but the most optimum density was observed when the sample was fabricated through double step processing (1.8046 g/cm3). Slight increment in hardness and ultimate compressive strength were observed for Mg-Zn/HAp composite that was fabricated through double step processing (58.09 HV, 132.19 MPa), as compared to Mg-Zn/HAp produced through single step processing (47.18 HV, 122.49 MPa).

The record of iceberg roll generated waves from sediments and seismics

NASA Astrophysics Data System (ADS)

Rosser, N. J.; Szczucinski, W.; Strzelecki, M.; Long, A. J.; Norman, E. C.; Dunning, S.; Drewniak, M.

2013-12-01

Iceberg-roll tsunamis in coastal settings have been observed to generate significant local waves, that hold potential to be recorded in coastal depositional records. Capturing the past magnitude and frequency of such events remains challenging, hindered by a lack of a good understanding of the nature, recurrence and scale of iceberg rolls, and more specifically those rolls that generate waves. Here we consider the sedimentary evidence for iceberg rolls in West Central Greenland, based upon survey of depositional environments in a range of open and confined coastal environments. We examine both an open 80 km fjord setting, and a series of confined ice-marginal beaches. We combine a detailed interpretation of sediment deposits from shore-normal transects with wider-scale high-resolution terrestrial laser scanning of sediments. Our sites - Vaigat, which separates Disko Island from the Nussuaq Peninsular, and the northern shore of Icefjord - both have a recent history of tsunamis, triggered variously by large rock avalanches, landslides and iceberg rolls. Icebergs in Vaigat and Icefjord are observed to undergo frequent failure and roll, generating - where circumstances permit - nearshore waves of meter-scale. To obtain a more detailed understanding of the likely recurrence of such iceberg roll waves and to consider their influence upon the preserved sedimentary record, we undertook an intensive 2-month monitoring campaign during sea-ice free conditions in summer 2013 to determine the patterns in the location, magnitude, frequency and timing of iceberg roll waves. Innovatively, using microseismic monitoring combined with time-lapse photography and weather monitoring, we derive a first-order model of the occurrence of iceberg roll waves. We then use this to inform our interpretation of deposits in these two environments, and consider the presence and absence of records of iceberg roll deposits in such settings. The study was funded by Polish National Science Centre grant No. 2011/01/B/ST10/01553.

Discrete Element Method Simulations of the Inter-Particle Contact Parameters for the Mono-Sized Iron Ore Particles

PubMed Central

Li, Tongqing; Peng, Yuxing; Zhu, Zhencai; Zou, Shengyong; Yin, Zixin

2017-01-01

Aiming at predicting what happens in reality inside mills, the contact parameters of iron ore particles for discrete element method (DEM) simulations should be determined accurately. To allow the irregular shape to be accurately determined, the sphere clump method was employed in modelling the particle shape. The inter-particle contact parameters were systematically altered whilst the contact parameters between the particle and wall were arbitrarily assumed, in order to purely assess its impact on the angle of repose for the mono-sized iron ore particles. Results show that varying the restitution coefficient over the range considered does not lead to any obvious difference in the angle of repose, but the angle of repose has strong sensitivity to the rolling/static friction coefficient. The impacts of the rolling/static friction coefficient on the angle of repose are interrelated, and increasing the inter-particle rolling/static friction coefficient can evidently increase the angle of repose. However, the impact of the static friction coefficient is more profound than that of the rolling friction coefficient. Finally, a predictive equation is established and a very close agreement between the predicted and simulated angle of repose is attained. This predictive equation can enormously shorten the inter-particle contact parameters calibration time that can help in the implementation of DEM simulations. PMID:28772880

Elevated-temperature flow strength, creep resistance and diffusion welding characteristics of Ti-gAl-2Nb-1Ta-0.8Mo

NASA Technical Reports Server (NTRS)

Whittenberger, J. D.; Moore, T. J.

1977-01-01

A study of the flow strength, creep resistance and diffusion welding characteristics of the titanium alloy Ti-6Al-2Nb-1Ta-0.8Mo was conducted. Two mill-processed forms of this alloy were examined. The forged material was essentially processed above the beta transus while the rolled form was subjected to considerable work below the beta transus. Between 1150 and 1250 K, the forged material was stronger and more creep resistant than the rolled alloy. Both forms exhibit superplastic characteristics in this temperature range. Strain measurements during diffusion welding experiments at 1200 K reveal that weld interfaces have no measurable effect on the overall creep deformation. Significant deformation appears to be necessary to produce a quality diffusion weld between superplastic materials. A 'soft' interlayer inserted between faying surfaces would seemingly allow manufacture of quality diffusion welds with little overall deformation.

New Nomenclatures for Heat Treatments of Additively Manufactured Titanium Alloys

NASA Astrophysics Data System (ADS)

Baker, Andrew H.; Collins, Peter C.; Williams, James C.

2017-07-01

The heat-treatment designations and microstructure nomenclatures for many structural metallic alloys were established for traditional metals processing, such as casting, hot rolling or forging. These terms do not necessarily apply for additively manufactured (i.e., three-dimensionally printed or "3D printed") metallic structures. The heat-treatment terminology for titanium alloys generally implies the heat-treatment temperatures and their sequence relative to a thermomechanical processing step (e.g., forging, rolling). These designations include: β-processing, α + β-processing, β-annealing, duplex annealing and mill annealing. Owing to the absence of a thermomechanical processing step, these traditional designations can pose a problem when titanium alloys are first produced via additive manufacturing, and then heat-treated. This communication proposes new nomenclatures for heat treatments of additively manufactured titanium alloys, and uses the distinct microstructural features to provide a correlation between traditional nomenclature and the proposed nomenclature.

Structure of large-scale flows and their oscillation in the thermal convection of liquid gallium.

PubMed

Yanagisawa, Takatoshi; Yamagishi, Yasuko; Hamano, Yozo; Tasaka, Yuji; Yoshida, Masataka; Yano, Kanako; Takeda, Yasushi

2010-07-01

This investigation observed large-scale flows in liquid gallium and the oscillation with Rayleigh-Bénard convection. An ultrasonic velocity profiling method was used to visualize the spatiotemporal flow pattern of the liquid gallium in a horizontally long rectangular vessel. Measuring the horizontal component of the flow velocity at several lines, an organized roll-like structure with four cells was observed in the 1×10(4)-2×10(5) range of Rayleigh numbers, and the rolls show clear oscillatory behavior. The long-term fluctuations in temperature observed in point measurements correspond to the oscillations of the organized roll structure. This flow structure can be interpreted as the continuous development of the oscillatory instability of two-dimensional roll convection that is theoretically investigated around the critical Rayleigh number. Both the velocity of the large-scale flows and the frequency of the oscillation increase proportional to the square root of the Rayleigh number. This indicates that the oscillation is closely related to the circulation of large-scale flow.

Children's behavioral pain reactions during local anesthetic injection using cotton-roll vibration method compared with routine topical anesthesia: A randomized controlled trial.

PubMed

Bagherian, Ali; Sheikhfathollahi, Mahmood

2016-01-01

Topical anesthesia has been widely advocated as an important component of atraumatic administration of intraoral local anesthesia. The aim of this study was to use direct observation of children's behavioral pain reactions during local anesthetic injection using cotton-roll vibration method compared with routine topical anesthesia. Forty-eight children participated in this randomized controlled clinical trial. They received two separate inferior alveolar nerve block or primary maxillary molar infiltration injections on contralateral sides of the jaws by both cotton-roll vibration (a combination of topical anesthesia gel, cotton roll, and vibration for physical distraction) and control (routine topical anesthesia) methods. Behavioral pain reactions of children were measured according to the author-developed face, head, foot, hand, trunk, and cry (FHFHTC) scale, resulting in total scores between 0 and 18. The total scores on the FHFHTC scale ranged between 0-5 and 0-10 in the cotton-roll vibration and control methods, respectively. The mean ± standard deviation values of total scores on FHFHTC scale were lower in the cotton-roll vibration method (1.21 ± 1.38) than in control method (2.44 ± 2.18), and this was statistically significant (P < 0.001). It may be concluded that the cotton-roll vibration method can be more helpful than the routine topical anesthesia in reducing behavioral pain reactions in children during local anesthesia administration.

A rolling-sliding bench test for investigating rear axle lubrication

DOE PAGES

Stump, Benjamin C.; Zhou, Yan; Viola, Michael B.; ...

2018-02-07

An automotive rear axle is composed of a set of hypoid gears, whose contact surfaces experience a complex combination of rolling contact fatigue damage and sliding wear. Full-scale rear axle dynamometer tests are used in the industry for efficiency and durability assessment. Here, this study developed a bench-scale rolling-sliding test protocol by simulating the contact pressure, oil temperature, and lubrication regime experienced in a dynamometer duty cycle test. Initial bench results have demonstrated the ability of generating both rolling contact-induced micropitting and sliding wear and the feasibility of investigating the impact of slide-to-roll ratio, surface roughness, test duration, and oilmore » temperature on the friction behavior, vibration noise, and surface damage. Finally, this bench test will allow studying candidate rear axle lubricants and materials under relevant conditions.« less

A rolling-sliding bench test for investigating rear axle lubrication

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stump, Benjamin C.; Zhou, Yan; Viola, Michael B.

An automotive rear axle is composed of a set of hypoid gears, whose contact surfaces experience a complex combination of rolling contact fatigue damage and sliding wear. Full-scale rear axle dynamometer tests are used in the industry for efficiency and durability assessment. Here, this study developed a bench-scale rolling-sliding test protocol by simulating the contact pressure, oil temperature, and lubrication regime experienced in a dynamometer duty cycle test. Initial bench results have demonstrated the ability of generating both rolling contact-induced micropitting and sliding wear and the feasibility of investigating the impact of slide-to-roll ratio, surface roughness, test duration, and oilmore » temperature on the friction behavior, vibration noise, and surface damage. Finally, this bench test will allow studying candidate rear axle lubricants and materials under relevant conditions.« less

Online detecting system of roller wear based on laser-linear array CCD technology

NASA Astrophysics Data System (ADS)

Guo, Yuan

2010-10-01

Roller is an important metallurgy tool in the rolling mill. And the surface of a roller affects the quantity of the rolling product directly. After using a period of time, roller must be repaired or replaced. Examining the profile of a working roller between the intervals of rolling is called online detecting for roller wear. The study of online detecting roller wear is very important for selecting the grinding time in reason, reducing the exchanging times of rollers, improving the quality of the product and realizing online grinding rollers. By applying the laser-linear array CCD detective technology, a method for online non-touch detecting roller wear was brought forward. The principle, composition and the operation process of the linear array CCD detecting system were expatiated. And an error compensation algorithm is exactly calculated to offset the shift of the roller axis in this measurement system. So the stability and the accuracy were improved remarkably. The experiment proves that the accuracy of the detecting system reaches to the demand of practical production process. It can provide a new method of high speed and high accuracy online detecting for roller wear.

Development of Fine-Grained, Low-Carbon Bainitic Steels with High Strength and Toughness Produced Through the Conventional Hot-Rolling and Air-Cooling

NASA Astrophysics Data System (ADS)

Dhua, Sanjay Kumar; Sarkar, Partha Pratim; Saxena, Atul; Jha, Bimal Kumar

2016-12-01

Low-carbon bainitic steels have created enormous interest among scientists across the world in the past few decades because of their high strength, toughness, and weldability replacing the conventional quenched and tempered medium-carbon steels. Three experimental steels with varying alloy additions were made in a 100-kg laboratory induction furnace and cast into 100-mm-diameter cylindrical ingots. These ingots were hot-rolled and air-cooled to 6-mm plates in an experimental rolling mill with selected thermomechanical parameters. Steels processed through this process provided an ultrafine low-carbon bainitic microstructure with maximum yield strength (YS) and ultimate tensile strength (UTS) 575 and 705 MPa, respectively. The Charpy impact toughness of the experimental steels was excellent, and at 253 K (-20 °C), it varied from 114 to 170 Joules. Cu-B-added steel was found to give an optimum combination of strength, YS-575 MPa, and toughness, 114 J at 253 K (-20 °C). Thus, fine-grained, low-carbon bainitic steels could be developed with a proper combination of alloying elements and thermomechanical parameters even by air-cooling.

Rolling bearing fault detection and diagnosis based on composite multiscale fuzzy entropy and ensemble support vector machines

NASA Astrophysics Data System (ADS)

Zheng, Jinde; Pan, Haiyang; Cheng, Junsheng

2017-02-01

To timely detect the incipient failure of rolling bearing and find out the accurate fault location, a novel rolling bearing fault diagnosis method is proposed based on the composite multiscale fuzzy entropy (CMFE) and ensemble support vector machines (ESVMs). Fuzzy entropy (FuzzyEn), as an improvement of sample entropy (SampEn), is a new nonlinear method for measuring the complexity of time series. Since FuzzyEn (or SampEn) in single scale can not reflect the complexity effectively, multiscale fuzzy entropy (MFE) is developed by defining the FuzzyEns of coarse-grained time series, which represents the system dynamics in different scales. However, the MFE values will be affected by the data length, especially when the data are not long enough. By combining information of multiple coarse-grained time series in the same scale, the CMFE algorithm is proposed in this paper to enhance MFE, as well as FuzzyEn. Compared with MFE, with the increasing of scale factor, CMFE obtains much more stable and consistent values for a short-term time series. In this paper CMFE is employed to measure the complexity of vibration signals of rolling bearings and is applied to extract the nonlinear features hidden in the vibration signals. Also the physically meanings of CMFE being suitable for rolling bearing fault diagnosis are explored. Based on these, to fulfill an automatic fault diagnosis, the ensemble SVMs based multi-classifier is constructed for the intelligent classification of fault features. Finally, the proposed fault diagnosis method of rolling bearing is applied to experimental data analysis and the results indicate that the proposed method could effectively distinguish different fault categories and severities of rolling bearings.

Control law parameterization for an aeroelastic wind-tunnel model equipped with an active roll control system and comparison with experiment

NASA Technical Reports Server (NTRS)

Perry, Boyd, III; Dunn, H. J.; Sandford, Maynard C.

1988-01-01

Nominal roll control laws were designed, implemented, and tested on an aeroelastically-scaled free-to-roll wind-tunnel model of an advanced fighter configuration. The tests were performed in the NASA Langley Transonic Dynamics Tunnel. A parametric study of the nominal roll control system was conducted. This parametric study determined possible control system gain variations which yielded identical closed-loop stability (roll mode pole location) and identical roll response but different maximum control-surface deflections. Comparison of analytical predictions with wind-tunnel results was generally very good.

Surficial geologic map of the Elizabethtown 30' x 60' quadrangle, North Carolina

USGS Publications Warehouse

Weems, Robert E.; Lewis, William C.; Crider, E. Allen

2011-01-01

The Elizabethtown 30' x 60' quadrangle is located in southeastern North Carolina between Fayetteville and Wilmington. Most of the area is flat to gently rolling, although steep slopes occur locally along some of the larger streams. Total relief in the area is slightly over 210 feet (ft), with elevations ranging from slightly less than 10 ft above sea level along the Black River (east of Rowan in the southeastern corner of the map) to slightly over 220 ft in the northwestern corner northeast of Hope Mills. The principal streams in the area are the Cape Fear, Black, South, and Lumber Rivers, which on average flow from northwest to southeast across the map area. The principal north-south roads are Interstate Route 95, Interstate Route 40, U.S. Route 117, U.S. Route 301, U.S. Route 421, and U.S. Route 701, and the principal east-west roads are N.C. State Route 241 and N.C. State Route 41. This part of North Carolina is primarily rural and agricultural. The largest communities in and adjacent to the area are Elizabethtown, Hope Mills, Clinton, Warsaw, and Lumberton. The map lies entirely within the Atlantic Coastal Plain physiographic province. Outstanding features of this area are the large number of sand-rimmed Carolina bays, five of which contain enough water to constitute natural lakes: Bay Tree Lake, Salter Lake, Little Singletary Lake, Singletary Lake, and White Lake. These are associated with widespread windblown sand deposits on which are grown abundant crops of blueberries. The extent and distribution of these deposits have been estimated based on a combination of augerhole, outcrop, and light-detection and ranging (LIDAR) data. The geology of the Elizabethtown 30' x 60' quadrangle was originally mapped on 32 7.5-minute quadrangles at 1:24,000 scale and then compiled on this 1:100,000-scale base. The base-map topographic contours on this compilation are shown in meters; the cross sections, structure contours, and well and corehole basement elevations have been carried over unconverted from the 1:24,000-scale maps and are shown in feet.

Bearing fatigue investigation 3

NASA Technical Reports Server (NTRS)

Nahm, A. H.; Bamberger, E. N.; Signer, H. R.

1982-01-01

The operating characteristics of large diameter rolling-element bearings in the ultra high speed regimes expected in advanced turbine engines for high performance aircraft were investigated. A high temperature lubricant, DuPont Krytox 143 AC, was evaluated at bearing speeds to 3 million DN. Compared to the results of earlier, similar tests using a MIL-L-23699 (Type II) lubricant, bearings lubricated with the high density Krytox fluid showed significantly higher power requirements. Additionally, short bearing lives were observed when this fluid was used with AISI M50 bearings in an air atmosphere. The primary mode of failure was corrosion initiated surface distress (fatigue) on the raceways. The potential of a case-carburized bearing to sustain a combination of high-tangential and hertzian stresses without experiencing race fracture was also investigated. Limited full scale bearing tests of a 120 mm bore ball bearing at a speed of 25,000 rpm (3 million DN) indicated that a carburized material could sustain spalling fatigue without subsequent propagation to fracture. Planned life tests of the carburized material had to be aborted, however, because of apparent processing-induced material defects.

Evaluation of rice husk ash as filler in tread compounds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fernandes, M. R. S., E-mail: monica.fernandes@lanxess.com; Furtado, C. R. G., E-mail: russi@globo.com, E-mail: ana.furtado.sousa@gmail.com; Sousa, A. M. F. de, E-mail: russi@globo.com, E-mail: ana.furtado.sousa@gmail.com

Rice which is one of the largest agriculture crops produces around 22% of rice rusk during its milling process. This material is mainly used as fuel for energy generation, which results in an ash, which disposal represents an environmental issue. The rice husk ash (RHA) contains over than 70% of silica in an amorphous form and a lot of applications is being developed for it all over the world. The use of silica as a filler in the tire industry is growing since it contributes significantly to the reduction of fuel consumption of the automobiles, allowing at the same timemore » better traction (safety). This paper presents an evaluation of the use of RHA as filler in rubber tread compounds prepared in lab scale and compares its performance with compounds prepared with commercial silica and carbon black, the fillers normally used in tire industry. Mechanical and rheological properties are evaluated, with emphasis for tan delta as an indicator of tread performance related with rolling resistance (fuel consumption) and wet grip/traction (safety)« less

Research Toward Developing an Understanding of Crystallographic Texture on Mechanical Properties of Titanium Alloys

DTIC Science & Technology

1977-01-01

S~g mechanisms are offered to rationalize the several mechanical pro - perty improvements noted in this work. Crack growth velocities induced by...plate is random. Commercial mill rolled plate pro - "duct is more often than not produced with a random array of basal poles (i.e., mechanical property...EU - ~co Li.aC 1/4" thick plate. Table V descr.bas each of these pro - cedures in some detail. As one can note from Table V, three distinct types of

An Aluminum Rolling Mill is not a Secondary Metal Production Plant Under 40 CFR 52.21

EPA Pesticide Factsheets

This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

Polyimide Boosts High-Temperature Performance

NASA Technical Reports Server (NTRS)

2008-01-01

Maverick Corporation, of Blue Ash, Ohio, licensed DMBZ-15 polyimide technology from Glenn Research Center. This ultrahigh-temperature material provides substantial weight savings and reduced machining costs compared to the same component made with more traditional metallic materials. DMBZ-15 has a wide range of applications from aerospace (aircraft engine and airframe components, space transportation systems, and missiles) to non-aerospace (oil drilling, rolling mill), and is particularly well-suited to use as face sheets with honey cones or thermal protection systems for reusable launch vehicles, which encounter elevated temperatures during launch and re-entry.

Investigation at Low Speeds of the Effect of Aspect Ratio and Sweep on Rolling Stability Derivatives of Untapered Wings

NASA Technical Reports Server (NTRS)

Goodman, Alex; Fisher, Lewis R

1950-01-01

A low-scale wind-tunnel investigation was conducted in rolling flow to determine the effects of aspect ratio and sweep (when varied independently) on the rolling stability derivatives for a series of untapered wings. The rolling-flow equipment of the Langley stability tunnel was used for the tests. The data of the investigation have been used to develop a method of accounting for the effects of the drag on the yawing moment due to rolling throughout the lift range.

Continuous roll-to-roll growth of graphene films by chemical vapor deposition

NASA Astrophysics Data System (ADS)

Hesjedal, Thorsten

2011-03-01

Few-layer graphene is obtained in atmospheric chemical vapor deposition on polycrystalline copper in a roll-to-roll process. Raman and x-ray photoelectron spectroscopy were employed to confirm the few-layer nature of the graphene film, to map the inhomogeneities, and to study and optimize the growth process. This continuous growth process can be easily scaled up and enables the low-cost fabrication of graphene films for industrial applications.

Researchers' Bibliography for Raven's Progressive Matrices and Mill Hill Vocabulary Scales.

ERIC Educational Resources Information Center

Court, J. H., Comp.

This annotated bibliography enables researchers who are using Raven's Progressive Matrices or the Mill Hill Vocabulary Scales to become familiar with other work that used these tests. The bibliography derives from Raven's own collection of sources, updated to the end of 1971. The major division of material is by tests rather than subject areas;…

Research and Development Trend of Shape Control for Cold Rolling Strip

NASA Astrophysics Data System (ADS)

Wang, Dong-Cheng; Liu, Hong-Min; Liu, Jun

2017-09-01

Shape is an important quality index of cold rolling strip. Up to now, many problems in the shape control domain have not been solved satisfactorily, and a review on the research progress in the shape control domain can help to seek new breakthrough directions. In the past 10 years, researches and applications of shape control models, shape control means, shape detection technology, and shape control system have achieved significant progress. In the aspect of shape control models, the researches in the past improve the accuracy, speed and robustness of the models. The intelligentization of shape control models should be strengthened in the future. In the aspect of the shape control means, the researches in the past focus on the roll optimization, mill type selection, process optimization, local strip shape control, edge drop control, and so on. In the future, more attention should be paid to the coordination control of both strip shape and other quality indexes, and the refinement of control objective should be strengthened. In the aspects of shape detection technology and shape control system, some new types of shape detection meters and shape control systems are developed and have successfully industrial applications. In the future, the standardization of shape detection technology and shape control system should be promoted to solve the problem of compatibility. In general, the four expected development trends of shape control for cold rolling strip in the future are intelligentization, coordination, refinement, and standardization. The proposed research provides new breakthrough directions for improving shape quality.

Development of Low Carbon Niobium Bearing High Strength F-B Dual Phase Steel with High Hole Expansion Property

NASA Astrophysics Data System (ADS)

Zhang, Lin; Xia, Ming-sheng; Xiong, Zi-liu; Du, Yan-bing; Qiao, Zhi-ming; Zhang, Hong-bo

In the study a low carbon niobium bearing high strength F-B dual phase automobile steel with high hole expansion property has been investigated. Steels of different chemical composition have been investigated by simulation experiments of controlled rolling and cooling process to study the influences of chemical elements, especially for C,Nb and Ti, and cooling pattern on the mechanical properties, flangeability and microstructure of strips. So-called 3-stages cooling pattern was adopted in simulation experiments, combining ultra fast cooling in first stage, air cooling in middle stage and fast cooling in the last stage, and at the end of run-out table the temperature of rolled pieces drop to below Bs point. Optical microstructure and SEM morphology have been observed. Results indicate that it is possible to obtain dual phase microstructure of polygonal ferrite plus bainite in adopting 3-stages cooling pattern. The low temperature coiling method using 3-step controlled cooling pattern after hot rolling is effective to produce low carbon Nb bearing steel with high balance of strength-ductility-flangeability, in addition, higher carbon content of steel tend to be detrimental to flangeability of steel, due to much carbide precipitation at ferrite boundary. Based on the results of simulation experiments mill trial has been carried out and hot rolled high strength steel with tensile strength higher as 600Mpa and hole expansion ratio higher as 100% has been developed successfully.

Roll-to-Roll printed large-area all-polymer solar cells with 5% efficiency based on a low crystallinity conjugated polymer blend

NASA Astrophysics Data System (ADS)

Gu, Xiaodan; Zhou, Yan; Gu, Kevin; Kurosawa, Tadanori; Yan, Hongping; Wang, Cheng; Toney, Micheal; Bao, Zhenan

The challenge of continuous printing in high efficiency large-area organic solar cells is a key limiting factor for their widespread adoption. We present a materials design concept for achieving large-area, solution coated all-polymer bulk heterojunction (BHJ) solar cells with stable phase separation morphology between the donor and acceptor. The key concept lies in inhibiting strong crystallization of donor and acceptor polymers, thus forming intermixed, low crystallinity and mostly amorphous blends. Based on experiments using donors and acceptors with different degree of crystallinity, our results showed that microphase separated donor and acceptor domain sizes are inversely proportional to the crystallinity of the conjugated polymers. This methodology of using low crystallinity donors and acceptors has the added benefit of forming a consistent and robust morphology that is insensitive to different processing conditions, allowing one to easily scale up the printing process from a small scale solution shearing coater to a large-scale continuous roll-to-roll (R2R) printer. We were able to continuously roll-to-roll slot die print large area all-polymer solar cells with power conversion efficiencies of 5%, with combined cell area up to 10 cm2. This is among the highest efficiencies realized with R2R coated active layer organic materials on flexible substrate. DOE BRIDGE sunshot program. Office of Naval Research.

Roll-to-Roll Printed Large-Area All-Polymer Solar Cells with 5% Efficiency Based on a Low Crystallinity Conjugated Polymer Blend

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gu, Xiaodan; Zhou, Yan; Gu, Kevin

The challenge of continuous printing in high-efficiency large-area organic solar cells is a key limiting factor for their widespread adoption. We present a materials design concept for achieving large-area, solution-coated all-polymer bulk heterojunction solar cells with stable phase separation morphology between the donor and acceptor. The key concept lies in inhibiting strong crystallization of donor and acceptor polymers, thus forming intermixed, low crystallinity, and mostly amorphous blends. Based on experiments using donors and acceptors with different degree of crystallinity, the results show that microphase separated donor and acceptor domain sizes are inversely proportional to the crystallinity of the conjugated polymers.more » This particular methodology of using low crystallinity donors and acceptors has the added benefit of forming a consistent and robust morphology that is insensitive to different processing conditions, allowing one to easily scale up the printing process from a small-scale solution shearing coater to a large-scale continuous roll-to-roll (R2R) printer. Large-area all-polymer solar cells are continuously roll-to-roll slot die printed with power conversion efficiencies of 5%, with combined cell area up to 10 cm 2. This is among the highest efficiencies realized with R2R-coated active layer organic materials on flexible substrate.« less

Roll-to-Roll Printed Large-Area All-Polymer Solar Cells with 5% Efficiency Based on a Low Crystallinity Conjugated Polymer Blend

DOE PAGES

Gu, Xiaodan; Zhou, Yan; Gu, Kevin; ...

2017-03-07

The challenge of continuous printing in high-efficiency large-area organic solar cells is a key limiting factor for their widespread adoption. We present a materials design concept for achieving large-area, solution-coated all-polymer bulk heterojunction solar cells with stable phase separation morphology between the donor and acceptor. The key concept lies in inhibiting strong crystallization of donor and acceptor polymers, thus forming intermixed, low crystallinity, and mostly amorphous blends. Based on experiments using donors and acceptors with different degree of crystallinity, the results show that microphase separated donor and acceptor domain sizes are inversely proportional to the crystallinity of the conjugated polymers.more » This particular methodology of using low crystallinity donors and acceptors has the added benefit of forming a consistent and robust morphology that is insensitive to different processing conditions, allowing one to easily scale up the printing process from a small-scale solution shearing coater to a large-scale continuous roll-to-roll (R2R) printer. Large-area all-polymer solar cells are continuously roll-to-roll slot die printed with power conversion efficiencies of 5%, with combined cell area up to 10 cm 2. This is among the highest efficiencies realized with R2R-coated active layer organic materials on flexible substrate.« less

On the impact of forced roll convection on vertical turbulent transport in cold air outbreaks

NASA Astrophysics Data System (ADS)

Gryschka, Micha; Fricke, Jens; Raasch, Siegfried

2014-11-01

We investigated the impact of roll convection on the convective boundary layer and vertical transports in different cold air outbreak (CAO) scenarios using large eddy simulations (LES). The organization of convection into rolls was triggered by upstream heterogeneities in the surface temperature, representing ice and water. By changing the sea ice distribution in our LES, we were able to simulate a roll and a nonroll case for each scenario. Furthermore, the roll wavelength was varied by changing the scale of the heterogeneity. The characteristics of the simulated rolls and cloud streets, such as aspect ratios, orientation of the roll axes, and downstream extensions of single rolls agreed closely with observations in CAO situations. The vertical turbulent fluxes, calculated for each simulation, were decomposed into contributions from rolls and from unorganized turbulence. Even though our results confirmed that rolls triggered by upstream heterogeneities can substantially contribute to vertical turbulent fluxes, the total fluxes were not affected by the rolls.

Coupled thermal-fluid-mechanics analysis of twin roll casting of A7075 aluminum alloy

NASA Astrophysics Data System (ADS)

Lee, Yun-Soo; Kim, Hyoung-Wook; Cho, Jae-Hyung; Chun, Se-Hwan

2017-09-01

Better understanding of temperature distribution and roll separation force during twin roll casting of aluminum alloys is critical to successfully fabricate good quality of aluminum strips. Therefore, the simulation techniques are widely applied to understand the twin roll casting process in a comprehensive way and to reduce the experimental time and cost of trial and error. However, most of the conventional approaches are considered thermally coupled flow, or thermally coupled mechanical behaviors. In this study, a fully coupled thermal-fluid-mechanical analysis of twin roll casting of A7075 aluminum strips was carried out using the finite element method. Temperature profile, liquid fraction and metal flow of aluminum strips with different thickness were predicted. Roll separation force and roll temperatures were experimentally obtained from a pilot-scale twin roll caster, and those results were compared with model predictions. Coupling the fluid of the liquid melt to the thermal and mechanical modeling reasonably predicted roll temperature distribution and roll separation force during twin roll casting.

Fault diagnosis of rolling element bearing using a new optimal scale morphology analysis method.

PubMed

Yan, Xiaoan; Jia, Minping; Zhang, Wan; Zhu, Lin

2018-02-01

Periodic transient impulses are key indicators of rolling element bearing defects. Efficient acquisition of impact impulses concerned with the defects is of much concern to the precise detection of bearing defects. However, transient features of rolling element bearing are generally immersed in stochastic noise and harmonic interference. Therefore, in this paper, a new optimal scale morphology analysis method, named adaptive multiscale combination morphological filter-hat transform (AMCMFH), is proposed for rolling element bearing fault diagnosis, which can both reduce stochastic noise and reserve signal details. In this method, firstly, an adaptive selection strategy based on the feature energy factor (FEF) is introduced to determine the optimal structuring element (SE) scale of multiscale combination morphological filter-hat transform (MCMFH). Subsequently, MCMFH containing the optimal SE scale is applied to obtain the impulse components from the bearing vibration signal. Finally, fault types of bearing are confirmed by extracting the defective frequency from envelope spectrum of the impulse components. The validity of the proposed method is verified through the simulated analysis and bearing vibration data derived from the laboratory bench. Results indicate that the proposed method has a good capability to recognize localized faults appeared on rolling element bearing from vibration signal. The study supplies a novel technique for the detection of faulty bearing. Copyright © 2018. Published by Elsevier Ltd.

The study on deformation characterization in micro rolling for ultra-thin strip

NASA Astrophysics Data System (ADS)

Xie, H. B.; Manabe, K.; Furushima, T.; Jiang, Z. Y.

2013-12-01

The demand for miniaturized parts and miniaturized semi-finished products is increasing. Metal forming processes cannot be simply scaled down to produce miniaturized micro parts and microforming processes have the capability of improving mass production and minimizing material waste. In this study, experimental and theoretical investigations on the micro rolling process have proven that the micro rolling deformation of thin strip is influenced by size effects from specimen sizeon flow stress and friction coefficient. The analytical and finite element (FE) models for describing the size effect related phenomena for SUS 304 stainless steel, such as the change of flow stress, friction and deformation behaviour, are proposed. The material surface constraint and the material deformation mode are critical in determination of material flow stress curve. The identified deformation and mechanics behaviours provide a basis for further exploration of the material deformation behaviour in plastic deformation of micro scale and the development of micro scale products via micro rolling.

A co-production of sugars, lignosulfonates, cellulose, and cellulose nanocrystals from ball-milled woods

Treesearch

Lanxing Du; Jinwu Wang; Yang Zhang; Chusheng Qi; Michael P. Wolcott; Zhiming Yu

2017-01-01

This study demonstrated the technical potential for the large-scale co-production of sugars, lignosulfonates, cellulose, and cellulose nanocrystals. Ball-milled woods with two particle sizes were prepared by ball milling for 80 min or 120 min (BMW80, BMW120) and then enzymatically hydrolyzed. 78.3% cellulose conversion of...

Computational Fluid Dynamics Modeling of Macrosegregation and Shrinkage in Large-Diameter Steel Roll Castings

NASA Astrophysics Data System (ADS)

Nastac, Laurentiu

2011-12-01

Minimizing macrosegregation and shrinkage in large cast steel mill rolls challenges the limits of commercial foundry technology. Processing improvements have been achieved by balancing the total heat input of casting with the rate of heat extraction from the surface of the roll in the mold. A submerged entry nozzle (SEN) technique that injects a dilute alloy addition through a nozzle into the partially solidified net-shaped roll ingot can mitigate both centerline segregation and midradius channel segregate conditions. The objective of this study is to optimize the melt chemistry, solidification, and SEN conditions to minimize centerline and midradius segregation, and then to improve the quality of the transition region between the outer shell and the diluted interior region. To accomplish this objective, a multiphase, multicomponent computational fluid dynamics (CFD) code was developed for studying the macrosegregation and shrinkage under various casting conditions for a 65-ton, 1.6-m-diameter steel roll. The developed CFD framework consists of solving for the volume fraction of phases (air and steel mixture), temperature, flow, and solute balance in multicomponent alloy systems. Thermal boundary conditions were determined by measuring the temperature in the mold at several radial depths and height locations. The thermophysical properties including viscosity of steel alloy used in the simulations are functions of temperature. The steel mixture in the species-transfer model consists of the following elements: Fe, Mn, Si, S, P, C, Cr, Mo, and V. Density and liquidus temperature of the steel mixture are locally affected by the segregation of these elements. The model predictions were validated against macrosegregation measured from pieces cut from the 65-ton roll. The effect of key processing parameters such as melt composition and superheat of both the shell and the dilute interior alloy are addressed. The influence of mold type and thickness on macrosegregation and shrinkage also are discussed.

Estimating sawmill processing capacity for tongass timber: 2007 and 2008 update

Treesearch

Susan J. Alexander; Daniel J. Parrent

2010-01-01

In spring and summer of 2008 and 2009, sawmill production capacity and utilization information was collected from major wood manufacturers in southeast Alaska. The estimated mill capacity in southeast Alaska for calendar year 2007 was 292,350 thousand board feet (mbf) (log scale), and for calendar year 2008 was 282,350 mbf (log scale). Mill production in calendar year...

Estimating sawmill processing capacity for Tongass timber: 2009 and 2010 Update

Treesearch

Susan J. Alexander; Daniel J. Parrent

2012-01-01

In spring and summer of 2010 and 2011, sawmill production capacity and wood utilization information was collected from major wood manufacturers in southeast Alaska. The estimated mill capacity in southeast Alaska for calendar year (CY) 2009 was 249,350 thousand board feet (mbf) (log scale), and for CY 2010 was 155,850 mbf (log scale), including idle sawmills. Mill...

Needle terpenoid composition of Pinus halepensis (Mill.) Trees infested by the scale insect Marchalina hellenica (Genn.) in Greece

Treesearch

Athanassios Gallis; Carlos Arrabal; Aristotle C. Papageorgiou; Maria C. Garcia-Vallejo

2012-01-01

Needle terpenoid composition was determined by using GLC-MS in Pinus halepensis (Mill.) trees that were infested and not infested by the scale insect Marchalina hellenica. The study area was within the Forest National Park of the Cape Sounion, southern Attica region, Greece. A total of 43 compounds, 32 of which were identified...

New technology and energy-saving equipment for production of composite materials

NASA Astrophysics Data System (ADS)

Romanovich, A. A.; Glagolev, S. N.; Babaevsky, A. N.

2018-03-01

The article considers industrial technology and energy-saving equipment for cement and composite binder production with a reduction in energy intensity of the process up to 50% due to the synergetic effect during mechanic activation of the raw mix with the replacement of part of the clinker component with the mineral hydro-active additive. The technological process is based on the sequential introduction of components in dispersed phases into the feed mixture in the grinding path and at the stage of product separation with certain dispersed characteristics. The increase in the energy efficiency of the line is achieved by the joint operation of the press roller aggregate, which is the development of BSTU named after V.G. Shoukhov, and rotor-vortex mills of a very fine grinding of a new design. The experienced design of the aggregate with the device for deagglomeration of the pressed tape allows combining the processes of grinding and disaggregation of the pressed material, thereby reducing the operating costs and increasing the efficiency of using the grinding unit. Comparative tests of cement samples obtained in energy-saving aggregates (PRA + RVM) are given which allowed establishing that their beam strength for compression and bending is higher by 15-20% than the traditional method obtained in a ball mill. An analytical expression is also given that allows one to determine the power consumed for the deagglomeration of crushed and pressed material between the main rolls, taking into account the geometric dimensions of the rolls and the physico-mechanical characteristics of the material.

Small-Molecule Organic Photovoltaic Modules Fabricated via Halogen-Free Solvent System with Roll-to-Roll Compatible Scalable Printing Method.

PubMed

Heo, Youn-Jung; Jung, Yen-Sook; Hwang, Kyeongil; Kim, Jueng-Eun; Yeo, Jun-Seok; Lee, Sehyun; Jeon, Ye-Jin; Lee, Donmin; Kim, Dong-Yu

2017-11-15

For the first time, the photovoltaic modules composed of small molecule were successfully fabricated by using roll-to-roll compatible printing techniques. In this study, blend films of small molecules, BTR and PC 71 BM were slot-die coated using a halogen-free solvent system. As a result, high efficiencies of 7.46% and 6.56% were achieved from time-consuming solvent vapor annealing (SVA) treatment and roll-to-roll compatible solvent additive approaches, respectively. After successful verification of our roll-to-roll compatible method on small-area devices, we further fabricated large-area photovoltaic modules with a total active area of 10 cm 2 , achieving a power conversion efficiency (PCE) of 4.83%. This demonstration of large-area photovoltaic modules through roll-to-roll compatible printing methods, even based on a halogen-free solvent, suggests the great potential for the industrial-scale production of organic solar cells (OSCs).

Free-Spinning-Tunnel Investigation to Determine the Effect of Spin-Recovery Rockets and Thrust Simulation on the Recovery Characteristics of a 1/21-Scale Model of the Chance Vought F7U-3 Airplane, TED No. NACA AD 3103

NASA Technical Reports Server (NTRS)

Burk, Sanger H., Jr.; Healy, Frederick M.

1955-01-01

An investigation of a l/21-scale model of the Chance Vought F7U-3 airplane in the co&at-load- condition has been conducted in the Langley 20-foot free-spinning tunnel, The recovery characteristics of the model were determined by use of spin-recovery rockets for the erect and inverted spinning condition. The rockets were so placed as to provide either a yawing or rolling moment about the model center of gravity. Also included in the investigation were tests to determine the effect of simulated engine thrust on the recovery characteristics of the model. On the basis of model tests, recoveries from erect and inverted spins were satisfactory when a yawing moment of 22,200 foot-pounds (full scale) was provided against the spin by rockets attached to the wing tips; the anti-spin yawing moment was applied for approximately 9 seconds, (full scale). Satisfactory recoveries were obtained from erect spins when a rolling moment of 22,200 foot-pounds (full scale) was provided with the spin (rolls right wing down in right spin). Although the inverted spin was satisfactorily terminated when a rolling moment of equal magnitude was provided, a roll rocket was not considered to be an optimum spin-recovery device to effect recoveries from inverted spins for this airplane because of resulting gyrations during spin recovery. Simulation of engine thrust had no apparent effect on the spin recovery characteristics.

Health-hazard evaluation determination report No. 75-91-489, Alcoa Aluminum Company, Warrick Operations, Newburgh, Indiana

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1978-05-01

A health-hazard evaluation, including mortality and follow-up environmental studies of worker exposure to oil mists, coal tar pitch volatiles (CTPV), and carbon monoxide in the rolling mills of the Alcoa Aluminum Company Warrick Operations, Newburgh, Indiana was conducted. The mortality study was inconclusive due to the small number of expected deaths and inaccurate medical histories. It was impossible to determine if Alcoa employees who died from cancer or ischemic heart disease did so as a result of their work exposure. Results of sampling indicate that employees working in the anode block fabrication and kiln area were exposed to hazardous levelsmore » of CTPV as cyclohexane solubles. Fifteen of 17 extracts contained benzo(a)pyrene. Employees were not exposed to hazardous levels of carbon monoxide and those in the hot mill area and cold mill oil houses were not exposed to oil mist at concentrations which would be expected to result in long-term adverse health effects. Recommendations included: pre-employment and periodic physical examination; environmental monitoring, effective engineering, and administrative controls to reduce exposure to CTPV to the lowest extent possible; disposable protective clothes for workers exposed to CTPV; and prompt decontamination of skin exposed to CTPV.« less

Precipitation Strengthening by Induction Treatment in High Strength Low Carbon Microalloyed Hot-Rolled Plates

NASA Astrophysics Data System (ADS)

Larzabal, G.; Isasti, N.; Rodriguez-Ibabe, J. M.; Uranga, P.

2018-03-01

The use of microalloyed steels in the production of thick plates is expanding due to the possibility of achieving attractive combinations of strength and toughness. As market requirements for high strength plates are increasing and new applications require reduced weight and innovative designs, novel approaches to attaining cost-effective grades are being developed. The mechanism of precipitation strengthening has been widely used in thin strip products, since the optimization of the coiling strategy offers interesting combinations in terms of final properties and microalloying additions. Precipitation strengthening in thick plates, however, is less widespread due to the limitation of interphase precipitation during continuous cooling after hot rolling. With the main objective of exploring the limits of this strengthening mechanism, laboratory thermomechanical simulations that reproduced plate hot rolling mill conditions were performed using low carbon steels microalloyed with Nb, NbMo, and TiMo additions. After continuous cooling to room temperature, a set of heat treatments using fast heating rates were applied simulating the conditions of induction heat treatments. An important increase of both yield and tensile strengths was measured after induction treatment without any important impairment in toughness properties. A significant precipitation hardening is observed in Mo-containing grades under specific heat treatment parameters.

Elevated temperature flow strength, creep resistance and diffusion welding characteristics of Ti-6Al-2Nb-1Ta-0.8Mo

NASA Technical Reports Server (NTRS)

Whittenberger, J. D.; Moore, T. J.

1979-01-01

A study of the flow strength, creep resistance and diffusion welding characteristics of the titanium alloy Ti-6Al-2Nb-1Ta-0.8Mo has been conducted. Two mill-processed forms of this alloy were examined. The forged material had been processed above the beta transus (approximately 1275 K) while the rolled form had been subjected to work below the beta transus. Between 1150 and 1250 K, the forged material was stronger and more creep resistant than the rolled alloy. Both forms exhibit superplastic characteristics in this temperature range. Strain measurements during diffusion welding experiments at 1200 K reveal that weld interfaces have no measurable effect on the overall creep deformation. Significant deformation appears to be necessary to produce a quality diffusion weld between superplastic materials. A 'soft' interlayer inserted between faying surfaces would seemingly allow manufacture of quality diffusion welds with little overall deformation.

Glancing-incidence focussed ion beam milling: A coherent X-ray diffraction study of 3D nano-scale lattice strains and crystal defects

DOE PAGES

Hofmann, Felix; Harder, Ross J.; Liu, Wenjun; ...

2018-05-11

Here, this study presents a detailed examination of the lattice distortions introduced by glancing incidence Focussed Ion Beam (FIB) milling. Using non-destructive multi-reflection Bragg coherent X-ray diffraction we probe damage formation in an initially pristine gold micro-crystal following several stages of FIB milling. These experiments allow access to the full lattice strain tensor in the micro-crystal with ~25 nm 3D spatial resolution, enabling a nano-scale analysis of residual lattice strains and defects formed. Our results show that 30 keV glancing incidence milling produces fewer large defects than normal incidence milling at the same energy. However the resulting residual lattice strainsmore » have similar magnitude and extend up to ~50 nm into the sample. At the edges of the milled surface, where the ion-beam tails impact the sample at near-normal incidence, large dislocation loops with a range of Burgers vectors are formed. Further glancing incidence FIB polishing with 5 keV ion energy removes these dislocation loops and reduces the lattice strains caused by higher energy FIB milling. However, even at the lower ion energy, damage-induced lattice strains are present within a ~20 nm thick surface layer. These results highlight the need for careful consideration and management of FIB damage. They also show that low-energy FIB-milling is an effective tool for removing FIB-milling induced lattice strains. This is important for the preparation of micro-mechanical test specimens and strain microscopy samples.« less

Glancing-incidence focussed ion beam milling: A coherent X-ray diffraction study of 3D nano-scale lattice strains and crystal defects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hofmann, Felix; Harder, Ross J.; Liu, Wenjun

Here, this study presents a detailed examination of the lattice distortions introduced by glancing incidence Focussed Ion Beam (FIB) milling. Using non-destructive multi-reflection Bragg coherent X-ray diffraction we probe damage formation in an initially pristine gold micro-crystal following several stages of FIB milling. These experiments allow access to the full lattice strain tensor in the micro-crystal with ~25 nm 3D spatial resolution, enabling a nano-scale analysis of residual lattice strains and defects formed. Our results show that 30 keV glancing incidence milling produces fewer large defects than normal incidence milling at the same energy. However the resulting residual lattice strainsmore » have similar magnitude and extend up to ~50 nm into the sample. At the edges of the milled surface, where the ion-beam tails impact the sample at near-normal incidence, large dislocation loops with a range of Burgers vectors are formed. Further glancing incidence FIB polishing with 5 keV ion energy removes these dislocation loops and reduces the lattice strains caused by higher energy FIB milling. However, even at the lower ion energy, damage-induced lattice strains are present within a ~20 nm thick surface layer. These results highlight the need for careful consideration and management of FIB damage. They also show that low-energy FIB-milling is an effective tool for removing FIB-milling induced lattice strains. This is important for the preparation of micro-mechanical test specimens and strain microscopy samples.« less

A study of energy-size relationship and wear rate in a lab-scale high pressure grinding rolls unit

NASA Astrophysics Data System (ADS)

Rashidi Dashtbayaz, Samira

This study is focused on two independent topics of energy-size relationship and wear-rate measurements on a lab-scale high pressure grinding rolls (HPGR). The first part of this study has been aimed to investigate the influence of the operating parameters and the feed characteristics on the particle-bed breakage using four different ore samples in a 200 mm x 100 mm lab-scale HPGR. Additionally, multistage grinding, scale-up from a lab-scale HPGR, and prediction of the particle size distributions have been studied in detail. The results obtained from energy-size relationship studies help with better understanding of the factors contributing to more energy-efficient grinding. It will be shown that the energy efficiency of the two configurations of locked-cycle and open multipass is completely dependent on the ore properties. A test procedure to produce the scale-up data is presented. The comparison of the scale-up factors between the data obtained on the University of Utah lab-scale HPGR and the industrial machine at the Newmont Boddington plant confirmed the applicability of lab-scale machines for trade-off studies. The population balance model for the simulation of product size distributions has shown to work well with the breakage function estimated through tests performed on the HPGR at high rotational speed. Selection function has been estimated by back calculation of population balance model with the help of the experimental data. This is considered to be a major step towards advancing current research on the simulation of particle size distribution by using the HPGR machine for determining the breakage function. Developing a technique/setup to measure the wear rate of the HPGR rolls' surface is the objective of the second topic of this dissertation. A mockup was initially designed to assess the application of the linear displacement sensors for measuring the rolls' weight loss. Upon the analysis of that technique and considering the corresponding sources of errors, the application of the 2D distance measurement sensors was studied to directly determine the wear rate on the lab-sale HPGR roll. Results obtained from various grinding tests revealed that the operating variations were beyond the expected wear rate. Based on the valuable outcomes from the two mentioned experimental designs, a cup-disc arrangement similar to piston-die apparatus was developed to indirectly measure the wear rate on the HPGR roll. The preliminary outputs proved to be promising for further investigation into the development of this method in order to relate the measured data on the cup-disc apparatus to the actual wear rate on the HPGR rolls.

Direct and precise measurement of displacement and velocity of flexible web in roll-to-roll manufacturing systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kang, Dongwoo; Lee, Eonseok; Choi, Young-Man

Interest in the production of printed electronics using a roll-to-roll system has gradually increased due to its low mass-production costs and compatibility with flexible substrate. To improve the accuracy of roll-to-roll manufacturing systems, the movement of the web needs to be measured precisely in advance. In this paper, a novel measurement method is developed to measure the displacement and velocity of the web precisely and directly. The proposed algorithm is based on the traditional single field encoder principle, and the scale grating has been replaced with a printed grating on the web. Because a printed grating cannot be as accuratemore » as a scale grating in a traditional encoder, there will inevitably be variations in pitch and line-width, and the motion of the web should be measured even though there are variations in pitch and line-width in the printed grating patterns. For this reason, the developed algorithm includes a precise method of estimating the variations in pitch. In addtion, a method of correcting the Lissajous curve is presented for precision phase interpolation to improve measurement accuracy by correcting Lissajous circle to unit circle. The performance of the developed method is evaluated by simulation and experiment. In the experiment, the displacement error was less than 2.5 μm and the velocity error of 1σ was about 0.25%, while the grating scale moved 30 mm.« less

Direct and precise measurement of displacement and velocity of flexible web in roll-to-roll manufacturing systems

NASA Astrophysics Data System (ADS)

Kang, Dongwoo; duk Kim, Young; Lee, Eonseok; Choi, Young-Man; Lee, Taik-Min; Kim, Dongmin

2013-12-01

Interest in the production of printed electronics using a roll-to-roll system has gradually increased due to its low mass-production costs and compatibility with flexible substrate. To improve the accuracy of roll-to-roll manufacturing systems, the movement of the web needs to be measured precisely in advance. In this paper, a novel measurement method is developed to measure the displacement and velocity of the web precisely and directly. The proposed algorithm is based on the traditional single field encoder principle, and the scale grating has been replaced with a printed grating on the web. Because a printed grating cannot be as accurate as a scale grating in a traditional encoder, there will inevitably be variations in pitch and line-width, and the motion of the web should be measured even though there are variations in pitch and line-width in the printed grating patterns. For this reason, the developed algorithm includes a precise method of estimating the variations in pitch. In addtion, a method of correcting the Lissajous curve is presented for precision phase interpolation to improve measurement accuracy by correcting Lissajous circle to unit circle. The performance of the developed method is evaluated by simulation and experiment. In the experiment, the displacement error was less than 2.5 μm and the velocity error of 1σ was about 0.25%, while the grating scale moved 30 mm.

Analytic Solution to the Problem of Aircraft Electric Field Mill Calibration

NASA Technical Reports Server (NTRS)

Koshak, William

2003-01-01

It is by no means a simple task to retrieve storm electric fields from an aircraft instrumented with electric field mill sensors. The presence of the aircraft distorts the ambient field in a complicated way. Before retrievals of the storm field can be made, the field mill measurement system must be "calibrated". In other words, a relationship between impressed (i.e., ambient) electric field and mill output must be established. If this relationship can be determined, it is mathematically inverted so that ambient field can be inferred from the mill outputs. Previous studies have primarily focused on linear theories where the relationship between ambient field and mill output is described by a "calibration matrix" M. Each element of the matrix describes how a particular component of the ambient field is enhanced by the aircraft. For example the product M(sub ix), E(sub x), is the contribution of the E(sub x) field to the i(th) mill output. Similarly, net aircraft charge (described by a "charge field component" E(sub q)) contributes an amount M(sub iq)E(sub q) to the output of the i(th) sensor. The central difficulty in obtaining M stems from the fact that the impressed field (E(sub x), E(sub y), E(sub z), E(sub q) is not known but is instead estimated. Typically, the aircraft is flown through a series of roll and pitch maneuvers in fair weather, and the values of the fair weather field and aircraft charge are estimated at each point along the aircraft trajectory. These initial estimates are often highly inadequate, but several investigators have improved the estimates by implementing various (ad hoc) iterative methods. Unfortunately, none of the iterative methods guarantee absolute convergence to correct values (i.e., absolute convergence to correct values has not been rigorously proven). In this work, the mathematical problem is solved directly by analytic means. For m mills installed on an arbitrary aircraft, it is shown that it is possible to solve for a single 2m-vector that provides all other needed variables (i.e., the unknown fair weather field, the unknown aircraft charge, and the unknown matrix M). Numerical tests of the solution, effects of measurement errors, and studies of solution non-uniqueness are ongoing as of this writing.

Mineral scale management Part III, Nonprocess elements in the paper industry

Treesearch

Alan W. Rudie; Peter W. Hart

2006-01-01

Efforts to comply with effluent standards have led to a situation where mills have little leeway in managing trace metals without developing mineral scale deposits. In most cases, the trace metals can be managed with minor process changes and siitable levels of process control. The principal tools available to the mill are pH and good washing in the first chorine...

Evaluation of residual uranium contamination in the dirt floor of an abandoned metal rolling mill.

PubMed

Glassford, Eric; Spitz, Henry; Lobaugh, Megan; Spitler, Grant; Succop, Paul; Rice, Carol

2013-02-01

A single, large, bulk sample of uranium-contaminated material from the dirt floor of an abandoned metal rolling mill was separated into different types and sizes of aliquots to simulate samples that would be collected during site remediation. The facility rolled approximately 11,000 tons of hot-forged ingots of uranium metal approximately 60 y ago, and it has not been used since that time. Thirty small mass (≈ 0.7 g) and 15 large mass (≈ 70 g) samples were prepared from the heterogeneously contaminated bulk material to determine how measurements of the uranium contamination vary with sample size. Aliquots of bulk material were also resuspended in an exposure chamber to produce six samples of respirable particles that were obtained using a cascade impactor. Samples of removable surface contamination were collected by wiping 100 cm of the interior surfaces of the exposure chamber with 47-mm-diameter fiber filters. Uranium contamination in each of the samples was measured directly using high-resolution gamma ray spectrometry. As expected, results for isotopic uranium (i.e., U and U) measured with the large-mass and small-mass samples are significantly different (p < 0.001), and the coefficient of variation (COV) for the small-mass samples was greater than for the large-mass samples. The uranium isotopic concentrations measured in the air and on the wipe samples were not significantly different and were also not significantly different (p > 0.05) from results for the large- or small-mass samples. Large-mass samples are more reliable for characterizing heterogeneously distributed radiological contamination than small-mass samples since they exhibit the least variation compared to the mean. Thus, samples should be sufficiently large in mass to insure that the results are truly representative of the heterogeneously distributed uranium contamination present at the facility. Monitoring exposure of workers and the public as a result of uranium contamination resuspended during site remediation should be evaluated using samples of sufficient size and type to accommodate the heterogeneous distribution of uranium in the bulk material.

Texture control of zircaloy tubing during tube reduction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nagai, N.; Kakuma, T.; Fujita, K.

1982-01-01

Seven batches of Zircaloy-2 nuclear fuel cladding tubes with different textures were processed from tube shells of the same size, by different reduction routes, using pilger and 3-roll mills. Based on the texture data of these tubes, the texture control of Zircaloy tubing, the texture gradient across the wall, and the texture change during annealing were studied. The deformation texture of Zicaloy-2 tubing was dependent on the tool's curvature and was independent of the dimensions of the mother tubes. The different slopes of texture gradients were observed between the tubing of higher strain ration and that of lower strain ratio.

Kinetic study of ferronickel slag grinding at variation of ball filling and ratio of feed to grinding balls

NASA Astrophysics Data System (ADS)

Sanwani, Edy; Ikhwanto, Muhammad

2017-01-01

The objective of this paper is to investigate the effect of ball filling and ratio of feed to grinding balls on the kinetic of grinding of ferronickel slag in a laboratory scale ball mill. The experiments were started by crushing the ferronickel slag samples using a roll crusher to produce -3 mesh (-6.7 mm) product. This product, after sampling and sample dividing processes, was then used as feed for grinding process. The grinding was performed with variations of ball filling and ratio of feed to grinding balls for 150 minutes. At every certain time interval, particle size analysis was carried out on the grinding product. The results of the experiments were also used to develop linear regression model of the effect of grinding variables on the P80 of the product. Based on this study, it was shown that P80 values of the grinding products declined sharply until 70 minutes of grinding time due to the dominant mechanism of impact breakage and then decreased slowly after 70 minutes until 150 minutes of grinding time due to dominant mechanism of attrition breakage. Kinetics study of the grinding process on variations of grinding ball filling showed that the optimum rate of formation of fine particles for 20%, 30%, 40% and 50% mill volume was achieved at a particle size of 400 µm in which the best initial rate of formation occurred at 50% volume of mill. At the variations of ratio of feed to grinding balls it was shown that the optimum rate of grinding for the ratio of 1:10, 1: 8 and 1: 6 was achieved at a particle size of 400 µm and for the ratio of 1: 4 was at 841 µm in which the best initial rate of formation occurred at a 1:10 ratio. In this study, it was also produced two regression models that can predict the P80 value of the grinding product as a function of the variables of grinding time, ball filling and the ratio of the feed to grinding balls.

Application of Roll-Isolated Inertial Measurement Units to the Instrumentation of Spinning Vehicles

DOE Office of Scientific and Technical Information (OSTI.GOV)

BEADER,MARK E.

Roll-isolated inertial measurement units are developed at Sandia for use in the instrumentation, guidance, and control of rapidly spinning vehicles. Roll-isolation is accomplished by supporting the inertial instrument cluster (gyros and accelerometers) on a single gimbal, the axis of which is parallel to the vehicle's spin axis. A rotary motor on the gimbal is driven by a servo loop to null the roll gyro output, thus inertially stabilizing the gimbal and instrument cluster while the vehicle spins around it. Roll-isolation prevents saturation of the roll gyro by the high vehicle spin rate, and vastly reduces measurement errors arising from gyromore » scale factor and alignment uncertainties. Nine versions of Sandia-developed roll-isolated inertial measurement units have been flown on a total of 27 flight tests since 1972.« less

AUTOMOTIVE REPAIR SHOP, DETAIL OF MILLS COAL BOILER WITH SCREWFEED ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

AUTOMOTIVE REPAIR SHOP, DETAIL OF MILLS COAL BOILER WITH SCREW-FEED COAL HOPPER ON RIGHT SIDE, WITH SCALE. - Cedar City Automotive Repair Shop, Automotive Repair Shop, 820 North Main Street, Cedar City, Iron County, UT

Recommended Practices to Improve Nurse Tank Safety: Phase II

DOT National Transportation Integrated Search

2013-12-01

This project addressed four topics: Pinhole leaks in nurse tanks were studied by radiography, serial milling, and side-angle ultrasound. These measurements indicated that welding surfaces contaminated by water, mill scale, rust, or other contamin...

User's manual for tooth contact analysis of face-milled spiral bevel gears with given machine-tool settings

NASA Technical Reports Server (NTRS)

Litvin, Faydor L.; Zhang, YI; Chen, Jui-Sheng

1991-01-01

Research was performed to develop a computer program that will: (1) simulate the meshing and bearing contact for face milled spiral beval gears with given machine tool settings; and (2) to obtain the output, some of the data is required for hydrodynamic analysis. It is assumed that the machine tool settings and the blank data will be taken from the Gleason summaries. The theoretical aspects of the program are based on 'Local Synthesis and Tooth Contact Analysis of Face Mill Milled Spiral Bevel Gears'. The difference between the computer programs developed herein and the other one is as follows: (1) the mean contact point of tooth surfaces for gears with given machine tool settings must be determined iteratively, while parameters (H and V) are changed (H represents displacement along the pinion axis, V represents the gear displacement that is perpendicular to the plane drawn through the axes of the pinion and the gear of their initial positions), this means that when V differs from zero, the axis of the pionion and the gear are crossed but not intersected; (2) in addition to the regular output data (transmission errors and bearing contact), the new computer program provides information about the contacting force for each contact point and the sliding and the so-called rolling velocity. The following topics are covered: (1) instructions for the users as to how to insert the input data; (2) explanations regarding the output data; (3) numerical example; and (4) listing of the program.

Flexure-based Roll-to-roll Platform: A Practical Solution for Realizing Large-area Microcontact Printing

PubMed Central

Zhou, Xi; Xu, Huihua; Cheng, Jiyi; Zhao, Ni; Chen, Shih-Chi

2015-01-01

A continuous roll-to-roll microcontact printing (MCP) platform promises large-area nanoscale patterning with significantly improved throughput and a great variety of applications, e.g. precision patterning of metals, bio-molecules, colloidal nanocrystals, etc. Compared with nanoimprint lithography, MCP does not require a thermal imprinting step (which limits the speed and material choices), but instead, extreme precision with multi-axis positioning and misalignment correction capabilities for large area adaptation. In this work, we exploit a flexure-based mechanism that enables continuous MCP with 500 nm precision and 0.05 N force control. The fully automated roll-to-roll platform is coupled with a new backfilling MCP chemistry optimized for high-speed patterning of gold and silver. Gratings of 300, 400, 600 nm line-width at various locations on a 4-inch plastic substrate are fabricated at a speed of 60 cm/min. Our work represents the first example of roll-to-roll MCP with high reproducibility, wafer scale production capability at nanometer resolution. The precision roll-to-roll platform can be readily applied to other material systems. PMID:26037147

Computational and Experimental Study of the Transient Transport Phenomena in a Full-Scale Twin-Roll Continuous Casting Machine

NASA Astrophysics Data System (ADS)

Xu, Mianguang; Li, Zhongyang; Wang, Zhaohui; Zhu, Miaoyong

2017-02-01

To gain a fundamental understanding of the transient fluid flow in twin-roll continuous casting, the current paper applies both large eddy simulation (LES) and full-scale water modeling experiments to investigate the characteristics of the top free surface, stirring effect of the roll rotation, boundary layer fluctuations, and backflow stability. The results show that, the characteristics of the top free surface and the flow field in the wedge-shaped pool region are quite different with/without the consideration of the roll rotation. The roll rotation decreases the instantaneous fluctuation range of the top free surface, but increases its horizontal velocity. The stirring effect of the roll rotating makes the flow field more homogenous and there exists clear shear flow on the rotating roll surface. The vortex shedding induced by the Kármán Vortex Street from the submerged entry nozzle (SEN) causes the "velocity magnitude wave" and strongly influences the boundary layer stability and the backflow stability. The boundary layer fluctuations or the "velocity magnitude wave" induced by the vortex shedding could give rise to the internal porosity. In strip continuous casting process, the vortex shedding phenomenon indicates that the laminar flow can give rise to instability and that it should be made important in the design of the feeding system and the setting of the operating parameters.

Fabrication of micro-lens array on convex surface by meaning of micro-milling

NASA Astrophysics Data System (ADS)

Zhang, Peng; Du, Yunlong; Wang, Bo; Shan, Debin

2014-08-01

In order to develop the application of the micro-milling technology, and to fabricate ultra-precision optical surface with complex microstructure, in this paper, the primary experimental research on micro-milling complex microstructure array is carried out. A complex microstructure array surface with vary parameters is designed, and the mathematic model of the surface is set up and simulated. For the fabrication of the designed microstructure array surface, a micro three-axis ultra-precision milling machine tool is developed, aerostatic guideway drove directly by linear motor is adopted in order to guarantee the enough stiffness of the machine, and novel numerical control strategy with linear encoders of 5nm resolution used as the feedback of the control system is employed to ensure the extremely high motion control accuracy. With the help of CAD/CAM technology, convex micro lens array on convex spherical surface with different scales on material of polyvinyl chloride (PVC) and pure copper is fabricated using micro tungsten carbide ball end milling tool based on the ultra-precision micro-milling machine. Excellent nanometer-level micro-movement performance of the axis is proved by motion control experiment. The fabrication is nearly as the same as the design, the characteristic scale of the microstructure is less than 200μm and the accuracy is better than 1μm. It prove that ultra-precision micro-milling technology based on micro ultra-precision machine tool is a suitable and optional method for micro manufacture of microstructure array surface on different kinds of materials, and with the development of micro milling cutter, ultraprecision micro-milling complex microstructure surface will be achieved in future.

Impact of Wind Shear Characteristics on Roll Structure in Idealized Hurricane Boundary Layers

NASA Astrophysics Data System (ADS)

Wang, S.; Jiang, Q.

2016-12-01

The hurricane boundary layer (HBL) is well known for its critical role in evolutions of tropical cyclones (TCs) as the air-sea interaction represents both the most important source and sink of the moist available energy and the kinetic energy, respectively. One of the frequently occurring features in the HBL is horizontal roll vortices, which have quasi-two dimensional coherent and banded structure extending from the surface to the top of the HBL. It is believed that this highly coherent structure, caused by the inflection point instability in the basic wind profiles, plays an important role in organizing turbulent transport. To understand this role, large-eddy simulations are conducted to investigate how the wind shear characteristics such as the shear strength and inflection-point level can impact the roll structure in terms of its spectral characteristics and turbulence organization. A mean wind profile nudging approach is used in the simulations to maintain the required mean wind shear without directly affecting turbulent motions. Enhancing the radial wind shear expands the roll horizontal scale and strengthens the roll's kinetic energy. Increasing the inflection-point level tends to produce a narrow and sharp peak in the power spectrum at the wavelength consistent with the roll spacing indicated by the instantaneous turbulent fields. The spectral tangential momentum flux, in particular, reaches a strong peak value at the roll wavelength. In contrast, the spectral radial momentum flux obtains its maximum at the wavelength that is usually shorter than the roll's, suggesting that the roll radial momentum transport is less efficient than the tangential. The most robust rolls are produced in a simulation with the highest inflection-point level and strong radial wind shear. Based on the spectral analysis, the roll-scale contribution to the turbulent momentum flux can reach 40% in the middle of the boundary layer.

HYM-flation: Yang-Mills cosmology with Horndeski coupling

NASA Astrophysics Data System (ADS)

Davydov, E.; Gal'tsov, D.

2016-02-01

We propose new mechanism for inflation using classical SU (2) Yang-Mills (YM) homogeneous and isotropic field non-minimally coupled to gravity via Horndeski prescription. This is the unique generally and gauge covariant ghost-free YM theory with the curvature-dependent action leading to second-order gravity and Yang-Mills field equations. We show that its solution space contains de Sitter boundary to which the trajectories are attracted for some finite time, ensuring the robust inflation with a graceful exit. The theory can be generalized to include the Higgs field leading to two-steps inflationary scenario, in which the Planck-scale YM-generated inflation naturally prepares the desired initial conditions for the GUT-scale Higgs inflation.

Northwest view of steel plate "cans" in bay 7 of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Northwest view of steel plate "cans" in bay 7 of the main pipe mill building. Historian for scale. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

13. VIEW OF FIRST FLOOR, LOOKING NORTHWEST. AT LEFT IS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. VIEW OF FIRST FLOOR, LOOKING NORTHWEST. AT LEFT IS A 'EUREKA O.K.' BAGGING SCALE (S. Howe Co., Silver Creek, New York). THE SUSPENSION-TYPE HOPPER SCALE WEIGHS BULK FEED AS IT DESCENDS INTO A BAG SECURED BY THE RING AT THE BASE OF THE SCALE. AT RIGHT, FINISHED PRODUCTS ARE READY FOR SALE. AT CENTER REAR IS ONE OF THE MILL'S TWO VERTICAL TWIN-SPIRAL MIXERS. Photographer: Jet T. Lowe, 1985 - Alexander's Grist Mill, Lock 37 on Ohio & Erie Canal, South of Cleveland, Valley View, Cuyahoga County, OH

Large Scale Evaluation fo Nickel Aluminide Rolls

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2005-09-01

This completed project was a joint effort between Oak Ridge National Laboratory and Bethlehem Steel (now Mittal Steel) to demonstrate the effectiveness of using nickel aluminide intermetallic alloy rolls as part of an updated, energy-efficient, commercial annealing furnace system.

Ultrashort-pulsed laser processing and solution based coating in roll-to-roll manufacturing of organic photovoltaics

NASA Astrophysics Data System (ADS)

Hördemann, C.; Hirschfelder, K.; Schaefer, M.; Gillner, A.

2015-09-01

The breakthrough of flexible organic electronics and especially organic photovoltaics is highly dependent on cost-efficient production technologies. Roll-2-Roll processes show potential for a promising solution in terms of high throughput and low-cost production of thin film organic components. Solution based material deposition and integrated laser patterning processes offer new possibilities for versatile production lines. The use of flexible polymeric substrates brings along challenges in laser patterning which have to be overcome. One main challenge when patterning transparent conductive layers on polymeric substrates are material bulges at the edges of the ablated area. Bulges can lead to short circuits in the layer system leading to device failure. Therefore following layers have to have a sufficient thickness to cover and smooth the ridge. In order to minimize the bulging height, a study has been carried out on transparent conductive ITO layers on flexible PET substrates. Ablation results using different beam shapes, such as Gaussian beam, Top-Hat beam and Donut-shaped beam, as well as multi-pass scribing and double-pulsed ablation are compared. Furthermore, lab scale methods for cleaning the patterned layer and eliminating bulges are contrasted to the use of additional water based sacrificial layers in order to obtain an alternative procedure suitable for large scale Roll-2-Roll manufacturing. Besides progress in research, ongoing transfer of laser processes into a Roll-2-Roll demonstrator is illustrated. By using fixed optical elements in combination with a galvanometric scanner, scribing, variable patterning and edge deletion can be performed individually.

Tensile deformation and fracture properties of a 14YWT nanostructured ferritic alloy

DOE PAGES

Alam, M. Ershadul; Pal, Soupitak; Fields, Kirk; ...

2016-08-13

Here, a new larger heat of a 14YWT nanostructured ferritic alloy (NFA), FCRD NFA-1, was synthesized by ball milling FeO and argon atomized Fe-14Cr-3W-0.4Ti-0.2Y (wt%) powders, followed by hot extrusion, annealing and cross rolling to produce an ≈10 mm-thick plate. NFA-1 contains a bimodal size distribution of pancake-shaped, mostly very fine scale, grains. The as-processed plate also contains a large population of microcracks running parallel to its broad surfaces. The small grains and large concentration of Y–Ti–O nano-oxides (NOs) result in high strength up to 800 °C. The uniform and total elongations range from ≈1–8%, and ≈10–24%, respectively. The strengthmore » decreases more rapidly above ≈400 °C and deformation transitions to largely viscoplastic creep by ≈600 °C. While the local fracture mechanism is generally ductile-dimple microvoid nucleation, growth and coalescence, perhaps the most notable feature of tensile deformation behavior of NFA-1 is the occurrence of periodic delamination, manifested as fissures on the fracture surfaces.« less

Micromechanical characterization of single-walled carbon nanotube reinforced ethylidene norbornene nanocomposites for self-healing applications

NASA Astrophysics Data System (ADS)

Aïssa, B.; Haddad, E.; Jamroz, W.; Hassani, S.; Farahani, R. D.; Merle, P. G.; Therriault, D.

2012-10-01

We report on the fabrication of self-healing nanocomposite materials, consisting of single-walled carbon nanotube (SWCNT) reinforced 5-ethylidene-2-norbornene (5E2N) healing agent—reacted with ruthenium Grubbs catalyst—by means of ultrasonication, followed by a three-roll mixing mill process. The kinetics of the 5E2N ring opening metathesis polymerization (ROMP) was studied as a function of the reaction temperature and the SWCNT loads. Our results demonstrated that the ROMP reaction was still effective in a large temperature domain ( - 15-45 °C), occurring at very short time scales (less than 1 min at 40 °C). On the other hand, the micro-indentation analysis performed on the SWCNT/5E2N nanocomposite material after its ROMP polymerization showed a clear increase in both the hardness and the Young modulus—up to nine times higher than that of the virgin polymer—when SWCNT loads range only from 0.1 to 2 wt%. The approach demonstrated here opens new prospects for using carbon nanotube and healing agent nanocomposite materials for self-repair functionality, especially in a space environment.

Process engineering with planetary ball mills.

PubMed

Burmeister, Christine Friederike; Kwade, Arno

2013-09-21

Planetary ball mills are well known and used for particle size reduction on laboratory and pilot scales for decades while during the last few years the application of planetary ball mills has extended to mechanochemical approaches. Processes inside planetary ball mills are complex and strongly depend on the processed material and synthesis and, thus, the optimum milling conditions have to be assessed for each individual system. The present review focuses on the insight into several parameters like properties of grinding balls, the filling ratio or revolution speed. It gives examples of the aspects of grinding and illustrates some general guidelines to follow for modelling processes in planetary ball mills in terms of refinement, synthesis' yield and contamination from wear. The amount of energy transferred from the milling tools to the powder is significant and hardly measurable for processes in planetary ball mills. Thus numerical simulations based on a discrete-element-method are used to describe the energy transfer to give an adequate description of the process by correlation with experiments. The simulations illustrate the effect of the geometry of planetary ball mills on the energy entry. In addition the imaging of motion patterns inside a planetary ball mill from simulations and video recordings is shown.

Digitalization in roll forming manufacturing

NASA Astrophysics Data System (ADS)

Sedlmaier, A.; Dietl, T.; Ferreira, P.

2017-09-01

Roll formed profiles are used in automotive chassis production as building blocks for the body-in-white. The ability to produce profiles with discontinuous cross sections, both in width and in depth, allows weight savings in the final automotive chassis through the use of load optimized cross sections. This has been the target of the 3D Roll Forming process. A machine concept is presented where a new forming concept for roll formed parts in combination with advanced robotics allowing freely positioned roll forming tooling in 3D space enables the production of complex shapes by roll forming. This is a step forward into the digitalization of roll forming manufacturing by making the process flexible and capable of rapid prototyping and production of small series of parts. Moreover, data collection in a large scale through the control system and integrated sensors lead to an increased understanding of the process and provide the basis to develop self-optimizing roll forming machines, increasing the productivity, quality and predictability of the roll-forming process. The first parts successfully manufactured with this new forming concept are presented.

Inflation with a smooth constant-roll to constant-roll era transition

NASA Astrophysics Data System (ADS)

Odintsov, S. D.; Oikonomou, V. K.

2017-07-01

In this paper, we study canonical scalar field models, with a varying second slow-roll parameter, that allow transitions between constant-roll eras. In the models with two constant-roll eras, it is possible to avoid fine-tunings in the initial conditions of the scalar field. We mainly focus on the stability of the resulting solutions, and we also investigate if these solutions are attractors of the cosmological system. We shall calculate the resulting scalar potential and, by using a numerical approach, we examine the stability and attractor properties of the solutions. As we show, the first constant-roll era is dynamically unstable towards linear perturbations, and the cosmological system is driven by the attractor solution to the final constant-roll era. As we demonstrate, it is possible to have a nearly scale-invariant power spectrum of primordial curvature perturbations in some cases; however, this is strongly model dependent and depends on the rate of the final constant-roll era. Finally, we present, in brief, the essential features of a model that allows oscillations between constant-roll eras.

Field-scale investigation of pulverized coal mill power consumption

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ganguli, R.; Bandopadhyay, S.

2008-08-15

Twenty field-scale tests were conducted in a 28 MW pulverized coal power plant in Healy, Alaska, to examine mill power consumption in relation to coal grind size. The intent in this field-scale study was to verify if grind size truly impacted power consumption by a detectable amount. The regression model developed from the data indicates that grind size does impact mill power consumption, with finer grinds consuming significantly more power than coarser grinds. However, other factors such as coal hardness (i.e. the lower the Hardgrove Grindability Index, or the harder the coal, the higher the power consumption) and mill throughputmore » (i.e., the higher the throughput, the higher the power consumption) had to be included before the impact of grind size could be isolated. It was also observed that combining amperage and flow rate into a single parameter, i.e., specific amperage, hurt modeling. Cost analysis based on the regression model indicate a power savings of $19,972 per year if the coal were ground to 50% passing 76 {mu}m rather than the industry standard of 70% passing 76 {mu}m. The study also demonstrated that size reduction constituted a significant portion of the power consumption.« less

Visual/motion cue mismatch in a coordinated roll maneuver

NASA Technical Reports Server (NTRS)

Shirachi, D. K.; Shirley, R. S.

1981-01-01

The effects of bandwidth differences between visual and motion cueing systems on pilot performance for a coordinated roll task were investigated. Visual and motion cue configurations which were acceptable and the effects of reduced motion cue scaling on pilot performance were studied to determine the scale reduction threshold for which pilot performance was significantly different from full scale pilot performance. It is concluded that: (1) the presence or absence of high frequency error information in the visual and/or motion display systems significantly affects pilot performance; and (2) the attenuation of motion scaling while maintaining other display dynamic characteristics constant, affects pilot performance.

Mimicking the Interfacial Dynamics of Flowing White Blood Cells

NASA Astrophysics Data System (ADS)

Santore, Maria

2015-03-01

The rolling of particles on surfaces, facilitated by hydrodynamic forces combined with localized surface interactions of the appropriate strengths, spatial arrangements, and ranges, is a technologically useful means of transporting and manipulating particles. One's intuition for the rolling of a marble or a car tire cannot be extrapolated down to microparticle length scales because the microparticle interactions are dominated by electrostatic, van der Waals, and hydrogen bonding interactions rather than a friction that depends on an imposed normal force. Indeed, our microparticle rolling systems are inspired by the rolling of white blood cells on the inner walls of venules as part of the innate immune response: Selectin molecules engage with their counterparts on the opposing surfaces to slow cell motion relative to that for freely flowing cells. In the resulting rolling signature, ligand-receptor binding and crack closing on the front of the cell are balanced with molecular dis-bonding and crack opening at the rear. The contact region is relatively static, allowing other interactions (for instance signaling) to occur for a finite duration. Thus, achieving particle rolling in synthetic systems is important because it facilitates particle-surface interactions in a continuous nonfouling fashion where the contact surface is continually renewed. In developing a synthetic model for this system, we employ polymers to modify flowing particles and /or planar collectors, producing heterogeneous interfaces which can support rolling or produce other motion signatures such as skipping, arrest, or free flow. We identify, in the synthetic system, combinations of variables that produce rolling and demonstrate how the distinction between rolling and arrest is not a simple matter of the adhesion strength between the particles and the collector. Rolling is a cooperative process and the coordination of binding in one location with dis-bonding in another requires appropriate length scales in the design of the interface and in the processing parameters as well.

Scale-model charge-transfer technique for measuring enhancement factors

NASA Technical Reports Server (NTRS)

Kositsky, J.; Nanevicz, J. E.

1991-01-01

Determination of aircraft electric field enhancement factors is crucial when using airborne field mill (ABFM) systems to accurately measure electric fields aloft. SRI used the scale model charge transfer technique to determine enhancement factors of several canonical shapes and a scale model Learjet 36A. The measured values for the canonical shapes agreed with known analytic solutions within about 6 percent. The laboratory determined enhancement factors for the aircraft were compared with those derived from in-flight data gathered by a Learjet 36A outfitted with eight field mills. The values agreed to within experimental error (approx. 15 percent).

Preparation and physicochemical properties of whole-bean soymilk.

PubMed

Kuo, Hsin-Yu; Chen, Shih-Hsin; Yeh, An-I

2014-01-22

Whole-bean soymilk has been prepared by using media-milling. Some characteristics of media-milled soymilk have been determined and compared with filtered soymilk (similar to commercial ones) and whole-bean soymilk prepared by blending. There existed particles in the nano/submicrometer scale in both media-milled and filtered soymilk. The particles in blended soymilk were greater than 1 μm. Media-milled soymilk was the most stable among three samples, even after autoclaving. Solid recovery (98.44 ± 0.16%), viscosity (160.59 ± 4.26 cps), dietary fiber (22.68 ± 0.97% on dry basis), total polyphenol recovery (95.15 ± 7.09%), and isoflavone content (4.42 ± 0.03 mg/g dry solid) of media-milled samples were greater than those of filtered ones. Aglycones, the most bioactive form of isoflavone, in autoclaved media-milled soymilk were more than 2-fold those in autoclaved filtered soymilk. With almost no okara generated, the media-milled soymilk retained fiber in soybeans which would be beneficial to human health.

Preparation, characterization and conductivity study of nitro-mercurated styrene butadiene rubber/silver doped zinc oxide nanocomposites

NASA Astrophysics Data System (ADS)

Anilkumar, T.; Naik, Adarsh Ajith; Ramesan, M. T.

2017-06-01

Here we report the preparation of nitromercurated styrene butadiene rubber (NMSBR)/silver doped zinc oxide nanocomposite by inexpensive and ecofriendly two roll mill mixing. The composites were characterized by UV, FTIR, XRD, SEM, TGA and conductivity measurements. UV and FTIR spectrum indicated the interfacial interaction between the polymer and nanoparticles.XRD and SEM images showed the uniform arrangement of nanoparticles within the macromolecular chain. TGA study indicated the better thermal resistance of the composite. The dielectric properties and AC conductivity ofnanocomposites were much greater than nitromercurated SBR and they may be used as multifunctional materials for nanoelectronic devices.

Synthesis and characterization of hematite pigment obtained from a steel waste industry.

PubMed

Prim, S R; Folgueras, M V; de Lima, M A; Hotza, D

2011-09-15

Pigments that meet environmental and technology requirements are the focus of the research in the ceramic sector. This study focuses on the synthesis of ceramic pigment by encapsulation of hematite in crystalline and amorphous silica matrix. Iron oxide from a metal sheet rolling process was used as chromophore. A different content of hematite and silica was homogenized by conventional and high energy milling. The powders obtained after calcinations between 1050 and 1200 °C for 2h were characterized by X-ray diffraction and SEM analysis. The pigments were applied to ceramic enamel and porcelain body. The effect of pigment was measured by comparing L*a*b* values of the heated samples. Results showed that the color developed is influenced by variables such as oxide content employed, conditions of milling and processing temperature. The results showed that the use of pigment developed does not interfere in microstructural characteristics of pigmented material. The best hue was obtained from samples with 15 wt% of chromophore, heated at 1200 °C in amorphous silica matrix. Copyright © 2011 Elsevier B.V. All rights reserved.

Combination process of diamond machining and roll-to-roll UV-replication for thin film micro- and nanostructures

NASA Astrophysics Data System (ADS)

Väyrynen, J.; Mönkkönen, K.; Siitonen, S.

2016-09-01

Roll-to-roll (R2R) ultraviolet (UV) curable embossing replication process is a highly accurate and cost effective way to replicate large quantities of thin film polymer parts. These structures can be used for microfluidics, LED-optics, light guides, displays, cameras, diffusers, decorative, laser sensing and measuring devices. In the R2R UV-process, plastic thin film coated with UV-curable lacquer, passes through an imprinting embossing drum and is then hardened by an UV-lamp. One key element for mastering this process is the ability to manufacture a rotating drum containing micro- and nanostructures. Depending on the pattern shapes, the drum can be directly machined by diamond machining or it can be done through wafer level lithographical process. Due to the shrinkage of UV-curable lacquer, the R2R drum pattern process needs to be prototyped few times, in order to get the desired performance and shape from the R2R produced part. To speed up the prototyping and overall process we have developed a combination process where planar diamond machining patterns are being turned into a drum roller. Initially diamond machined patterns from a planar surface are replicated on a polymer sheet using UV-replication. Secondly, a nickel stamper shim is grown form the polymer sheet and at the end the stamper is turned into a roller and used in the R2R process. This process allows various micro milled, turned, grooved and ruled structures to be made at thin film products through the R2R process. In this paper, the process flow and examples of fabricating R2R embossed UVcurable thin film micro- and nanostructures from planar diamond machined patterns, is reported.

CRN5EXP: Expert system for statistical quality control

NASA Technical Reports Server (NTRS)

Hentea, Mariana

1991-01-01

The purpose of the Expert System CRN5EXP is to assist in checking the quality of the coils at two very important mills: Hot Rolling and Cold Rolling in a steel plant. The system interprets the statistical quality control charts, diagnoses and predicts the quality of the steel. Measurements of process control variables are recorded in a database and sample statistics such as the mean and the range are computed and plotted on a control chart. The chart is analyzed through patterns using the C Language Integrated Production System (CLIPS) and a forward chaining technique to reach a conclusion about the causes of defects and to take management measures for the improvement of the quality control techniques. The Expert System combines the certainty factors associated with the process control variables to predict the quality of the steel. The paper presents the approach to extract data from the database, the reason to combine certainty factors, the architecture and the use of the Expert System. However, the interpretation of control charts patterns requires the human expert's knowledge and lends to Expert Systems rules.

Aerosol insecticide distribution inside a flour mill: Assessment using droplet measurements and bioassays

USDA-ARS?s Scientific Manuscript database

The distribution of aerosol applications of pyrethrin+methoprene, generated from a mechanical fogger, and pyrethrin+pyriproxyfen, dispensed from a pressurized cylinder, were characterized inside a pilot-scale flour mill using measurements of particle size and concentration and effects on adult confu...

Atomic scale study of ball milled Ni-Fe{sub 2}O{sub 3} using Mössbauer spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yadav, Ravi Kumar; Govindaraj, R., E-mail: govind@igcar.gov.in; Vinod, K.

Evolution of hyperfine fields at Fe atoms has been studied in a detailed manner in a mixture of Ni and α-Fe{sub 2}O{sub 3} subjected to high energy ball milling using Mossbauer spectroscopy. Mossbauer results indicate the dispersion of α-Fe{sub 2}O{sub 3} particles in Ni matrix in the as ball milled condition. Evolution of α-Fe{sub 2}O{sub 3} due to ball milling, reduction of the valence of associated Fe and possible interaction between the oxide particles with Ni in the matrix due to annealing treatments has been elucidated in the present study.

Minimisation of costs by using disintegration at a full-scale anaerobic digestion plant.

PubMed

Winter, A

2002-01-01

Various half-scale and lab-scale investigations have already shown that the disintegration of excess sludge is a possible pre-treatment to optimise anaerobic digestion. To control these results different methods of disintegration were investigated at a full-scale plant. Two stirred ball mills and a plant for oxidation with ozone were applied. A positive influence of disintegration on the anaerobic biodegradability can be established with application of a stirred ball mill. Biogas production as well as the degree of degradation were increased by about 20%. Laboratory investigations also validate that disintegration increases the polymer demand and leads to a lower solid content after dewatering. A higher pollution level of process water after dewatering even with ammonia and COD corroborates the results of the anaerobic degradation. Capital costs for the stirred ball mill, costs for energy, manpower and maintenance can be covered if the specific costs for disposal are high. If the development of costs in future and the current discussion about sludge disposal are taken into account sewage sludge disintegration can be a suitable technique to minimise costs at waste water treatment plants.

Stochastic inflation in phase space: is slow roll a stochastic attractor?

NASA Astrophysics Data System (ADS)

Grain, Julien; Vennin, Vincent

2017-05-01

An appealing feature of inflationary cosmology is the presence of a phase-space attractor, ``slow roll'', which washes out the dependence on initial field velocities. We investigate the robustness of this property under backreaction from quantum fluctuations using the stochastic inflation formalism in the phase-space approach. A Hamiltonian formulation of stochastic inflation is presented, where it is shown that the coarse-graining procedure—where wavelengths smaller than the Hubble radius are integrated out—preserves the canonical structure of free fields. This means that different sets of canonical variables give rise to the same probability distribution which clarifies the literature with respect to this issue. The role played by the quantum-to-classical transition is also analysed and is shown to constrain the coarse-graining scale. In the case of free fields, we find that quantum diffusion is aligned in phase space with the slow-roll direction. This implies that the classical slow-roll attractor is immune to stochastic effects and thus generalises to a stochastic attractor regardless of initial conditions, with a relaxation time at least as short as in the classical system. For non-test fields or for test fields with non-linear self interactions however, quantum diffusion and the classical slow-roll flow are misaligned. We derive a condition on the coarse-graining scale so that observational corrections from this misalignment are negligible at leading order in slow roll.

Rapid Prototyping of Slot Die Devices for Roll to Roll Production of EL Fibers

PubMed Central

Bellingham, Alyssa; Bromhead, Nicholas; Fontecchio, Adam

2017-01-01

There is a growing interest in fibers supporting optoelectrical properties for textile and wearable display applications. Solution-processed electroluminescent (EL) material systems can be continuously deposited onto fiber or yarn substrates in a roll-to-roll process, making it easy to scale manufacturing. It is important to have precise control over layer deposition to achieve uniform and reliable light emission from these EL fibers. Slot-die coating offers this control and increases the rate of EL fiber production. Here, we report a highly adaptable, cost-effective 3D printing model for developing slot dies used in automatic coating systems. The resulting slot-die coating system enables rapid, reliable production of alternating current powder-based EL (ACPEL) fibers and can be adapted for many material systems. The benefits of this system over dip-coating for roll-to-roll production of EL fibers are demonstrated in this work. PMID:28772954

Rapid Prototyping of Slot Die Devices for Roll to Roll Production of EL Fibers.

PubMed

Bellingham, Alyssa; Bromhead, Nicholas; Fontecchio, Adam

2017-05-29

There is a growing interest in fibers supporting optoelectrical properties for textile and wearable display applications. Solution-processed electroluminescent (EL) material systems can be continuously deposited onto fiber or yarn substrates in a roll-to-roll process, making it easy to scale manufacturing. It is important to have precise control over layer deposition to achieve uniform and reliable light emission from these EL fibers. Slot-die coating offers this control and increases the rate of EL fiber production. Here, we report a highly adaptable, cost-effective 3D printing model for developing slot dies used in automatic coating systems. The resulting slot-die coating system enables rapid, reliable production of alternating current powder-based EL (ACPEL) fibers and can be adapted for many material systems. The benefits of this system over dip-coating for roll-to-roll production of EL fibers are demonstrated in this work.

Effect of ball milling time on thermoelectric properties of bismuth telluride nanomaterials

NASA Astrophysics Data System (ADS)

Khade, Poonam; Bagwaiya, Toshi; Bhattacharaya, Shovit; Singh, Ajay; Jha, Purushottam; Shelke, Vilas

2018-04-01

The effect of different milling time on thermoelectric properties of bismuth telluride (Bi2Te3) was investigated. The nanomaterial was prepared by varying the ball milling time and followed by hot press sintering. The crystal structure and phase formation were verified by X-ray diffraction and Raman Spectroscopy. The experimental results show that electrical conductivity increases whereas thermal conductivity decreases with increasing milling time. The negative sign of seebeck coefficient indicate the n-type nature with majority charge carriers of electrons. A maximum figure of merit about 0.55 is achieved for l5hr ball milled Bi2Te3 sample. The present study demonstrates the simple and cost-effective method for synthesis of Bi2Te3 thermoelectric material at large scale thermoelectric applications.

Reconciling tensor and scalar observables in G-inflation

NASA Astrophysics Data System (ADS)

Ramírez, Héctor; Passaglia, Samuel; Motohashi, Hayato; Hu, Wayne; Mena, Olga

2018-04-01

The simple m2phi2 potential as an inflationary model is coming under increasing tension with limits on the tensor-to-scalar ratio r and measurements of the scalar spectral index ns. Cubic Galileon interactions in the context of the Horndeski action can potentially reconcile the observables. However, we show that this cannot be achieved with only a constant Galileon mass scale because the interactions turn off too slowly, leading also to gradient instabilities after inflation ends. Allowing for a more rapid transition can reconcile the observables but moderately breaks the slow-roll approximation leading to a relatively large and negative running of the tilt αs that can be of order ns‑1. We show that the observables on CMB and large scale structure scales can be predicted accurately using the optimized slow-roll approach instead of the traditional slow-roll expansion. Upper limits on |αs| place a lower bound of rgtrsim 0.005 and, conversely, a given r places a lower bound on |αs|, both of which are potentially observable with next generation CMB and large scale structure surveys.

Continuum strong-coupling expansion of Yang-Mills theory: quark confinement and infra-red slavery

NASA Astrophysics Data System (ADS)

Mansfield, Paul

1994-04-01

We solve Schrödinger's equation for the ground-state of four-dimensional Yang-Mills theory as an expansion in inverse powers of the coupling. Expectation values computed with the leading-order approximation are reduced to a calculation in two-dimensional Yang-Mills theory which is known to confine. Consequently the Wilson loop in the four-dimensional theory obeys an area law to leading order and the coupling becomes infinite as the mass scale goes to zero.

CMB quadrupole depression produced by early fast-roll inflation: Monte Carlo Markov chains analysis of WMAP and SDSS data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Destri, C.; Vega, H. J. de; Observatoire de Paris, LERMA, Laboratoire Associe au CNRS UMR 8112, 61, Avenue de l'Observatoire, 75014 Paris

Generically, the classical evolution of the inflaton has a brief fast-roll stage that precedes the slow-roll regime. The fast-roll stage leads to a purely attractive potential in the wave equations of curvature and tensor perturbations (while the potential is purely repulsive in the slow-roll stage). This attractive potential leads to a depression of the CMB quadrupole moment for the curvature and B-mode angular power spectra. A single new parameter emerges in this way in the early universe model: the comoving wave number k{sub 1} characteristic scale of this attractive potential. This mode k{sub 1} happens to exit the horizon preciselymore » at the transition from the fast-roll to the slow-roll stage. The fast-roll stage dynamically modifies the initial power spectrum by a transfer function D(k). We compute D(k) by solving the inflaton evolution equations. D(k) effectively suppresses the primordial power for k

Reactivity of Aluminum-Based Mixtures with Early Transition Metals

DTIC Science & Technology

2014-08-01

particles are no longer equiaxed but lenticular and lammelar. Dimensions of the heavily deformed Ti particles are considerably finer (30 µm in length by...same. The Hf particles look coarse under light milling and attain a more lenticular appearance with heavy milling. There is large-scale mixing in this

Systematics of constant roll inflation

NASA Astrophysics Data System (ADS)

Anguelova, Lilia; Suranyi, Peter; Wijewardhana, L. C. R.

2018-02-01

We study constant roll inflation systematically. This is a regime, in which the slow roll approximation can be violated. It has long been thought that this approximation is necessary for agreement with observations. However, recently it was understood that there can be inflationary models with a constant, and not necessarily small, rate of roll that are both stable and compatible with the observational constraint ns ≈ 1. We investigate systematically the condition for such a constant-roll regime. In the process, we find a whole new class of inflationary models, in addition to the known solutions. We show that the new models are stable under scalar perturbations. Finally, we find a part of their parameter space, in which they produce a nearly scale-invariant scalar power spectrum, as needed for observational viability.

Influence of rheology on realignment of mantle convective structure with plate motion after a plate reorganization

NASA Astrophysics Data System (ADS)

van Hunen, J.; Zhong, S.

2006-08-01

Small-scale convection (SSC) rolls below the oceanic lithosphere have the tendency to align with the large-scale shearing direction and thus with the plate motion direction relative to the deep mantle. Understanding the timescales of and processes responsible for realignment would contribute significantly to our understanding of the unresolved phenomena in the Pacific such as gravity lineations, small-scale seismic velocity variations, and intraplate volcanism that cannot be explained by hot spots. In this study we examine the evolution of those convection rolls when this relative plate motion direction is suddenly changed, as suggested by the kink in the Hawaii-Emperor seamount chain. Using three-dimensional numerical flow models, we investigate the realignment of SSC rolls after a change in plate motion direction. From the nature of the SSC, it is expected that rheological parameters dominate the characteristics of this realignment. Our results show that this is indeed the case. We find that (1) using constraints from onset timing of SSC, realignment of rolls can occur as fast as within 20 Ma, but might also take much longer, dependent on the rheology; (2) the realignment period is strongly correlated to the sum of large-scale shear stress induced by plate motion and small-scale shear stress from the SSC itself; (3) in a mantle deforming by dislocation creep, realignment occurs faster than by diffusion creep, because dislocation creep SSC is more vigorous; and (4) activation energy has little influence on the realignment time. Possible evidence for the realignment period might come from precise age determination of intraplate volcanism or azimuthal seismic anisotropy.

Controls on sublithospheric small-scale convection on Curie depths

NASA Astrophysics Data System (ADS)

Likerman, Jeremias; Zlotnik, Sergio; Chun-Feng, Li

2017-04-01

As the ocean lithosphere cools and thickens, its bottom layer goes unstable leading to sub-lithospheric small-scale convection (SSC). Since SSC was originally proposed, there have been considerable efforts regarding the understanding of the physics that rules the thermal instabilities of the SSC (e.g. Dumoulin et al, 1999; Solomatov and Moresi, 2000). Over the last several years, it is understood that the interaction between the plate movement and the SSC tends to form longitudinal (LRs or also called 'Richter rolls') and transverse rolls (TRs), of which the axis is parallel and perpendicular to the plate motion, respectively. The geometry of these rolls have been been recently inferred by Li et al (2013) using Curie depths from the North Atlantic as proxies for plates temperatures. They showed that Curie depths have a large oscillating and heterogeneous patterns that could be related to SSC. In the North Atlantic transverse rolls seem predominant. In this work we analyze, by means of 3D dynamical numerical simulations, the influence of SSC on the Curie depths patterns observed in the North Atlantic and Pacific plates. We investigate the behaviour of the Curie isotherms trying to determine if SSC is able to reproduce the observed data, and the influence of several poorly constrained rheological parameters. Our numerical simulations show that: a) using realistic laboratory-constrained rheologies and temperature it is possible to modify temperatures as low as those at Curie depths; b) transverse rolls are generated as well as longitudinal rolls on those isotherms; c) the spreading rate is a first order control on the developing of transverse rolls. References Dumoulin, C., Doin, M. P., & Fleitout, L. (1999). Heat transport in stagnant lid convection with temperature-and pressure-dependent Newtonian or non-Newtonian rheology. Journal of Geophysical Research: Solid Earth, 104(B6), 12759-12777. Li, C. F., Wang, J., Lin, J., & Wang, T. (2013). Thermal evolution of the North Atlantic lithosphere: new constraints from magnetic anomaly inversion with a fractal magnetization model. Geochemistry, Geophysics, Geosystems, 14(12), 5078-5105. Solomatov, V. S., & Moresi, L. N. (2000). Scaling of time-dependent stagnant lid convection: Application to small-scale convection on Earth and other terrestrial planets. Journal of Geophysical Research: Solid Earth, 105(B9), 21795-21817.

Dynamic correlations at different time-scales with empirical mode decomposition

NASA Astrophysics Data System (ADS)

Nava, Noemi; Di Matteo, T.; Aste, Tomaso

2018-07-01

We introduce a simple approach which combines Empirical Mode Decomposition (EMD) and Pearson's cross-correlations over rolling windows to quantify dynamic dependency at different time scales. The EMD is a tool to separate time series into implicit components which oscillate at different time-scales. We apply this decomposition to intraday time series of the following three financial indices: the S&P 500 (USA), the IPC (Mexico) and the VIX (volatility index USA), obtaining time-varying multidimensional cross-correlations at different time-scales. The correlations computed over a rolling window are compared across the three indices, across the components at different time-scales and across different time lags. We uncover a rich heterogeneity of interactions, which depends on the time-scale and has important lead-lag relations that could have practical use for portfolio management, risk estimation and investment decisions.

Comparison of high pressure homogenization and stirred bead milling for the production of nano-crystalline suspensions.

PubMed

Nakach, Mostafa; Authelin, Jean-René; Perrin, Marc-Antoine; Lakkireddy, Harivardhan Reddy

2018-05-19

Currently, the two technologies primarily used for the manufacturing of nano-crystalline suspensions using top down process (i.e. wet milling) are high pressure homogenization (HPH) and stirred bead milling (SBM). These two technologies are based upon different mechanisms, i.e., cavitation forces for HPH and shear forces for stirred bead milling. In this article, the HPH and SBM technologies are compared in terms of the impact of the suspension composition the process parameters and the technological configuration on milling performances and physical quality of the suspensions produced. The data suggested that both HPH and SBM are suitable for producing nano-crystalline suspensions, although SBM appeared more efficient than HPH, since the limit of milling (d 50 ) for SBM was found to be lower than that obtained with HPH (100 nm vs 200 nm). For both these technologies, regardless of the process parameters used for milling and the scale of manufacturing, the relationship of d 90 versus d 50 could be described by a unique master curve (technology signature of milling pathway) outlining that the HPH leads to more uniform particle size distribution as compared to SBM. Copyright © 2018 Elsevier B.V. All rights reserved.

X-15A-2 is rolled out of the paint shop after having the full scale ablative applied

NASA Image and Video Library

1967-06-23

X-15A-2 is rolled out of the paint shop after having the full scale ablative applied. In June 1967, the X-15A-2 rocket-powered research aircraft received a full-scale ablative coating to protect the craft from the high temperatures associated with hypersonic flight (above Mach 5). This pink eraser-like substance, applied to the X-15A-2 aircraft (56-6671), was then covered with a white sealant coat before flight. This coating would help the #2 aircraft reach the record speed of 4,520 mph (Mach 6.7).

Advanced bulk processing of lightweight materials for utilization in the transportation sector

NASA Astrophysics Data System (ADS)

Milner, Justin L.

The overall objective of this research is to develop the microstructure of metallic lightweight materials via multiple advanced processing techniques with potentials for industrial utilization on a large scale to meet the demands of the aerospace and automotive sectors. This work focused on (i) refining the grain structure to increase the strength, (ii) controlling the texture to increase formability and (iii) directly reducing processing/production cost of lightweight material components. Advanced processing is conducted on a bulk scale by several severe plastic deformation techniques including: accumulative roll bonding, isolated shear rolling and friction stir processing to achieve the multiple targets of this research. Development and validation of the processing techniques is achieved through wide-ranging experiments along with detailed mechanical and microstructural examination of the processed material. On a broad level, this research will make advancements in processing of bulk lightweight materials facilitating industrial-scale implementation. Where accumulative roll bonding and isolated shear rolling, currently feasible on an industrial scale, processes bulk sheet materials capable of replacing more expensive grades of alloys and enabling low-temperature and high-strain-rate formability. Furthermore, friction stir processing to manufacture lightweight tubes, made from magnesium alloys, has the potential to increase the utilization of these materials in the automotive and aerospace sectors for high strength - high formability applications. With the increased utilization of these advanced processing techniques will significantly reduce the cost associated with lightweight materials for many applications in the transportation sectors.

Impact Load Behavior between Different Charge and Lifter in a Laboratory-Scale Mill

PubMed Central

Yin, Zixin; Zhu, Zhencai; Yu, Zhangfa; Li, Tongqing

2017-01-01

The impact behavior between the charge and lifter has significant effect to address the mill processing, and is affected by various factors including mill speed, mill filling, lifter height and media shape. To investigate the multi-body impact load behavior, a series of experiments and Discrete Element Method (DEM) simulations were performed on a laboratory-scale mill, in order to improve the grinding efficiency and prolong the life of the lifter. DEM simulation hitherto has been extensively applied as a leading tool to describe diverse issues in granular processes. The research results shown as follows: The semi-empirical power draw of Bond model in this paper does not apply very satisfactorily for the ball mills, while the power draw determined by DEM simulation show a good approximation for the measured power draw. Besides, the impact force on the lifter was affected by mill speed, grinding media filling, lifter height and iron ore particle. The maximum percent of the impact force between 600 and 1400 N is at 70–80% of critical speed. The impact force can be only above 1400 N at the grinding media filling of 20%, and the maximum percent of impact force between 200 and 1400 N is obtained at the grinding media filling of 20%. The percent of impact force ranging from 0 to 200 N decreases with the increase of lifter height. However, this perfect will increase above 200 N. The impact force will decrease when the iron ore particles are added. Additionally, for the 80% of critical speed, the measured power draw has a maximum value. Increasing the grinding media filling increases the power draw and increasing the lifter height does not lead to any variation in power draw. PMID:28773243

Impact Load Behavior between Different Charge and Lifter in a Laboratory-Scale Mill.

PubMed

Yin, Zixin; Peng, Yuxing; Zhu, Zhencai; Yu, Zhangfa; Li, Tongqing

2017-07-31

The impact behavior between the charge and lifter has significant effect to address the mill processing, and is affected by various factors including mill speed, mill filling, lifter height and media shape. To investigate the multi-body impact load behavior, a series of experiments and Discrete Element Method (DEM) simulations were performed on a laboratory-scale mill, in order to improve the grinding efficiency and prolong the life of the lifter. DEM simulation hitherto has been extensively applied as a leading tool to describe diverse issues in granular processes. The research results shown as follows: The semi-empirical power draw of Bond model in this paper does not apply very satisfactorily for the ball mills, while the power draw determined by DEM simulation show a good approximation for the measured power draw. Besides, the impact force on the lifter was affected by mill speed, grinding media filling, lifter height and iron ore particle. The maximum percent of the impact force between 600 and 1400 N is at 70-80% of critical speed. The impact force can be only above 1400 N at the grinding media filling of 20%, and the maximum percent of impact force between 200 and 1400 N is obtained at the grinding media filling of 20%. The percent of impact force ranging from 0 to 200 N decreases with the increase of lifter height. However, this perfect will increase above 200 N. The impact force will decrease when the iron ore particles are added. Additionally, for the 80% of critical speed, the measured power draw has a maximum value. Increasing the grinding media filling increases the power draw and increasing the lifter height does not lead to any variation in power draw.

Application of fundamental principles to mineral scale reduction : case studies

Treesearch

Peter W. Hart; Alan W. Rudie

2005-01-01

This paper will present several successful case studies where scale has been eliminated in mills including calcium carbonate scale in a white liquor strainer, calcium oxalate scale in the D0 stage, enzymatic treatment of brown stock to eliminate oxalate scale, and control of barium sulfate scale.

Stochastic inflation in phase space: is slow roll a stochastic attractor?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grain, Julien; Vennin, Vincent, E-mail: julien.grain@ias.u-psud.fr, E-mail: vincent.vennin@port.ac.uk

An appealing feature of inflationary cosmology is the presence of a phase-space attractor, ''slow roll'', which washes out the dependence on initial field velocities. We investigate the robustness of this property under backreaction from quantum fluctuations using the stochastic inflation formalism in the phase-space approach. A Hamiltonian formulation of stochastic inflation is presented, where it is shown that the coarse-graining procedure—where wavelengths smaller than the Hubble radius are integrated out—preserves the canonical structure of free fields. This means that different sets of canonical variables give rise to the same probability distribution which clarifies the literature with respect to this issue.more » The role played by the quantum-to-classical transition is also analysed and is shown to constrain the coarse-graining scale. In the case of free fields, we find that quantum diffusion is aligned in phase space with the slow-roll direction. This implies that the classical slow-roll attractor is immune to stochastic effects and thus generalises to a stochastic attractor regardless of initial conditions, with a relaxation time at least as short as in the classical system. For non-test fields or for test fields with non-linear self interactions however, quantum diffusion and the classical slow-roll flow are misaligned. We derive a condition on the coarse-graining scale so that observational corrections from this misalignment are negligible at leading order in slow roll.« less

Abrasive rolling effects on material removal and surface finish in chemical mechanical polishing analyzed by molecular dynamics simulation

NASA Astrophysics Data System (ADS)

Si, Lina; Guo, Dan; Luo, Jianbin; Lu, Xinchun; Xie, Guoxin

2011-04-01

In an abrasive chemical mechanical polishing (CMP) process, materials were considered to be removed by abrasive sliding and rolling. Abrasive sliding has been investigated by many molecular dynamics (MD) studies; while abrasive rolling was usually considered to be negligible and therefore was rarely investigated. In this paper, an MD simulation was used to study the effects of abrasive rolling on material removal and surface finish in the CMP process. As the silica particle rolled across the silicon substrate, some atoms of the substrate were dragged out from their original positions and adhered to the silica particle, leaving some atomic vacancies on the substrate surface. Meanwhile, a high quality surface could be obtained. During the abrasive rolling process, the influencing factors of material removal, e.g., external down force and driving force, were also discussed. Finally, MD simulations were carried out to examine the effects of abrasive sliding on material removal under the same external down force as abrasive rolling. The results showed that the ability of abrasive rolling to remove material on the atomic scale was not notably inferior to that of abrasive sliding. Therefore, it can be proposed that both abrasive sliding and rolling play important roles in material removal in the abrasive CMP of the silicon substrate.

Nano-sized crystalline drug production by milling technology.

PubMed

Moribe, Kunikazu; Ueda, Keisuke; Limwikrant, Waree; Higashi, Kenjirou; Yamamoto, Keiji

2013-01-01

Nano-formulation of poorly water-soluble drugs has been developed to enhance drug dissolution. In this review, we introduce nano-milling technology described in recently published papers. Factors affecting the size of drug crystals are compared based on the preparation methods and drug and excipient types. A top-down approach using the comminution process is a method conventionally used to prepare crystalline drug nanoparticles. Wet milling using media is well studied and several wet-milled drug formulations are now on the market. Several trials on drug nanosuspension preparation using different apparatuses, materials, and conditions have been reported. Wet milling using a high-pressure homogenizer is another alternative to preparing production-scale drug nanosuspensions. Dry milling is a simple method of preparing a solid-state drug nano-formulation. The effect of size on the dissolution of a drug from nanoparticles is an area of fundamental research, but it is sometimes incorrectly evaluated. Here, we discuss evaluation procedures and the associated problems. Lastly, the importance of quality control, process optimization, and physicochemical characterization are briefly discussed.

Future of the Particle Replication in Nonwetting Templates (PRINT) Technology

PubMed Central

Xu, Jing; Wong, Dominica H. C.; Byrne, James D.; Chen, Kai; Bowerman, Charles

2014-01-01

Particle replication in nonwetting templates (PRINT) is a continuous, roll-to-roll, high-resolution molding technology which allows the design and synthesis of precisely defined micro- and nanoparticles. This technology adapts the lithographic techniques from the microelectronics industry and marries these with the roll-to-roll processes from the photographic film industry to enable researchers to have unprecedented control over particle size, shape, chemical composition, cargo, modulus, and surface properties. In addition, PRINT is a GMP-compliant (GMP = good manufacturing practice) platform amenable for particle fabrication on a large scale. Herein, we describe some of our most recent work involving the PRINT technology for application in the biomedical and material sciences. PMID:23670869

Net Shape Spin Formed Cryogenic Aluminum Lithium Cryogenic Tank Domes for Lower Cost Higher Performance Launch Vehicles

NASA Technical Reports Server (NTRS)

Curreri, Peter A.; Hoffman, Eric; Domack, Marcia; Brewster, Jeb; Russell, Carolyn

2013-01-01

With the goal of lower cost (simplified manufacturing and lower part count) and higher performance (higher strength to weight alloys) the NASA Technical Maturation Program in 2006 funded a proposal to investigate spin forming of space launch vehicle cryogenic tank domes. The project funding continued under the NASA Exploration Technology Development Program through completion in FY12. The first phase of the project involved spin forming of eight, 1 meter diameter "path finder" domes. Half of these were processed using a concave spin form process (MT Aerospace, Augsburg Germany) and the other half using a convex process (Spincraft, Boston MA). The convex process has been used to produce the Ares Common Bulkhead and the concave process has been used to produce dome caps for the Space Shuttle light weight external tank and domes for the NASDA H2. Aluminum Lithium material was chosen because of its higher strength to weight ratio than the Aluminum 2219 baseline. Aluminum lithium, in order to obtain the desired temper (T8), requires a cold stretch after the solution heat treatment and quench. This requirement favors the concave spin form process which was selected for scale up. This paper describes the results of processing four, 5.5 meter diameter (upper stage scale) net shaped spin formed Aluminum Lithium domes. In order to allow scalability beyond the limits of foundry and rolling mills (about 12 foot width) the circular blank contained one friction stir weld (heavy lifter scales require a flat blank containing two welds). Mechanical properties data (tensile, fracture toughness, stress corrosion, and simulated service testing) for the parent metal and weld will also be discussed.

Roll-To-Roll Printing of Meter-Scale Composite Transparent Electrodes with Optimized Mechanical and Optical Properties for Photoelectronics.

PubMed

Meng, Xiangchuan; Hu, Xiaotian; Yang, Xia; Yin, Jingping; Wang, Qingxia; Huang, Liqiang; Yu, Zoukangning; Hu, Ting; Tan, Licheng; Zhou, Weihua; Chen, Yiwang

2018-03-14

Flexible transparent electrodes are an indispensable component for flexible optoelectronic devices. In this work, the meter-scale composite transparent electrodes (CTEs) composed of poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) and Ag grid/polyethylene terephthalate (PET) with optimized mechanical and optical properties are demonstrated by slot-die roll-to-roll technique with solution printing method under a low cost ($15-20 per square meter), via control of the viscosity and surface energy of PEDOT:PSS ink as well as the printing parameters. The CTEs show excellent flexibility remaining 98% of the pristine value after bending 2000 times under various bending situations, and the square resistance ( R s ) of CTEs can be reduced to 4.5-5.0 Ω/sq with an appropriate transmittance. Moreover, the optical performances, such as haze, extinction coefficient, and refractive index, are investigated, as compared with indium tin oxide/PET, which are potential for the inexpensive optoelectronic flexible devices. The CTEs could be successfully employed in polymer solar cells with different areas, showing a maximal power conversion efficiency of 8.08%.

Shock compression response of cold-rolled Ni/Al multilayer composites

DOE PAGES

Specht, Paul E.; Weihs, Timothy P.; Thadhani, Naresh N.

2017-01-06

Uniaxial strain, plate-on-plate impact experiments were performed on cold-rolled Ni/Al multilayer composites and the resulting Hugoniot was determined through time-resolved measurements combined with impedance matching. The experimental Hugoniot agreed with that previously predicted by two dimensional (2D) meso-scale calculations. Additional 2D meso-scale simulations were performed using the same computational method as the prior study to reproduce the experimentally measured free surface velocities and stress profiles. Finally, these simulations accurately replicated the experimental profiles, providing additional validation for the previous computational work.

Modified dispersion relations, inflation, and scale invariance

NASA Astrophysics Data System (ADS)

Bianco, Stefano; Friedhoff, Victor Nicolai; Wilson-Ewing, Edward

2018-02-01

For a certain type of modified dispersion relations, the vacuum quantum state for very short wavelength cosmological perturbations is scale-invariant and it has been suggested that this may be the source of the scale-invariance observed in the temperature anisotropies in the cosmic microwave background. We point out that for this scenario to be possible, it is necessary to redshift these short wavelength modes to cosmological scales in such a way that the scale-invariance is not lost. This requires nontrivial background dynamics before the onset of standard radiation-dominated cosmology; we demonstrate that one possible solution is inflation with a sufficiently large Hubble rate, for this slow roll is not necessary. In addition, we also show that if the slow-roll condition is added to inflation with a large Hubble rate, then for any power law modified dispersion relation quantum vacuum fluctuations become nearly scale-invariant when they exit the Hubble radius.

In Situ Exfoliation of Graphene in Epoxy Resins: A Facile Strategy to Efficient and Large Scale Graphene Nanocomposites.

PubMed

Li, Yan; Zhang, Han; Crespo, Maria; Porwal, Harshit; Picot, Olivier; Santagiuliana, Giovanni; Huang, Zhaohui; Barbieri, Ettore; Pugno, Nicola M; Peijs, Ton; Bilotti, Emiliano

2016-09-14

Any industrial application aiming at exploiting the exceptional properties of graphene in composites or coatings is currently limited by finding viable production methods for large volumes of good quality and high aspect ratio graphene, few layer graphene (FLG) or graphite nanoplatelets (GNP). Final properties of the resulting composites are inherently related to those of the initial graphitic nanoparticles, which typically depend on time-consuming, resource-demanding and/or low yield liquid exfoliation processes. In addition, efficient dispersion of these nanofillers in polymer matrices, and their interaction, is of paramount importance. Here we show that it is possible to produce graphene/epoxy nanocomposites in situ and with high conversion of graphite to FLG/GNP through the process of three-roll milling (TRM), without the need of any additives, solvents, compatibilisers or chemical treatments. This readily scalable production method allows for more than 5 wt % of natural graphite (NG) to be directly exfoliated into FLG/GNP and dispersed in an epoxy resin. The in situ exfoliated graphitic nanoplatelets, with average aspect ratios of 300-1000 and thicknesses of 5-17 nm, were demonstrated to conferee exceptional enhancements in mechanical and electrical properties to the epoxy resin. The above conclusions are discussed and interpreted in terms of simple analytical models.

Adaptive attenuation of aliased ground roll using the shearlet transform

NASA Astrophysics Data System (ADS)

Hosseini, Seyed Abolfazl; Javaherian, Abdolrahim; Hassani, Hossien; Torabi, Siyavash; Sadri, Maryam

2015-01-01

Attenuation of ground roll is an essential step in seismic data processing. Spatial aliasing of the ground roll may cause the overlap of the ground roll with reflections in the f-k domain. The shearlet transform is a directional and multidimensional transform that separates the events with different dips and generates subimages in different scales and directions. In this study, the shearlet transform was used adaptively to attenuate aliased and non-aliased ground roll. After defining a filtering zone, an input shot record is divided into segments. Each segment overlaps adjacent segments. To apply the shearlet transform on each segment, the subimages containing aliased and non-aliased ground roll, the locations of these events on each subimage are selected adaptively. Based on these locations, mute is applied on the selected subimages. The filtered segments are merged together, using the Hanning function, after applying the inverse shearlet transform. This adaptive process of ground roll attenuation was tested on synthetic data, and field shot records from west of Iran. Analysis of the results using the f-k spectra revealed that the non-aliased and most of the aliased ground roll were attenuated using the proposed adaptive attenuation procedure. Also, we applied this method on shot records of a 2D land survey, and the data sets before and after ground roll attenuation were stacked and compared. The stacked section after ground roll attenuation contained less linear ground roll noise and more continuous reflections in comparison with the stacked section before the ground roll attenuation. The proposed method has some drawbacks such as more run time in comparison with traditional methods such as f-k filtering and reduced performance when the dip and frequency content of aliased ground roll are the same as those of the reflections.

Development of USPS Laboratory and pilot-scale testing protocols

Treesearch

Carl Houtman; Nancy Ross Sutherland; David Bormett; Donald Donermeyer

2000-01-01

The ultimate goal of the US Postal Service (USPS) Environmentally Benign Stamp Program is to develop stamp adhesives that can be removed by unit operations found in recycling mills. The maintenance of final product quality specifications for a recycling mill while loading the feedstock with a significant quantity of adhesive is the criterion for success of this program...

Fluid mechanics of slurry flow through the grinding media in ball mills

DOE Office of Scientific and Technical Information (OSTI.GOV)

Songfack, P.K.; Rajamani, R.K.

1995-12-31

The slurry transport within the ball mill greatly influences the mill holdup, residence time, breakage rate, and hence the power draw and the particle size distribution of the mill product. However, residence-time distribution and holdup in industrial mills could not be predicted a priori. Indeed, it is impossible to determine the slurry loading in continuously operating mills by direct measurement, especially in industrial mills. In this paper, the slurry transport problem is solved using the principles of fluid mechanics. First, the motion of the ball charge and its expansion are predicted by a technique called discrete element method. Then themore » slurry flow through the porous ball charge is tackled with a fluid-flow technique called the marker and cell method. This may be the only numerical technique capable of tracking the slurry free surface as it fluctuates with the motion of the ball charge. The result is a prediction of the slurry profile in both the radial and axial directions. Hence, it leads to the detailed description of slurry mass and ball charge within the mill. The model predictions are verified with pilot-scale experimental work. This novel approach based on the physics of fluid flow is devoid of any empiricism. It is shown that the holdup of industrial mills at a given feed percent solids can be predicted successfully.« less

Rayleigh convective instability in a cloud medium

NASA Astrophysics Data System (ADS)

Shmerlin, B. Ya.; Shmerlin, M. B.

2017-09-01

The problem of convective instability of an atmospheric layer containing a horizontally finite region filled with a cloud medium is considered. Solutions exponentially growing with time, i.e., solitary cloud rolls or spatially localized systems of cloud rolls, have been constructed. In the case of axial symmetry, their analogs are convective vortices with both ascending and descending motions on the axis and cloud clusters with ring-shaped convective structures. Depending on the anisotropy of turbulent exchange, the scale of vortices changes from the tornado scale to the scale of tropical cyclones. The solutions with descending motions on the axis can correspond to the formation of a tornado funnel or a hurricane eye in tropical cyclones.

Roll-to-Roll Gravure Printed Electrochemical Sensors for Wearable and Medical Devices.

PubMed

Bariya, Mallika; Shahpar, Ziba; Park, Hyejin; Sun, Junfeng; Jung, Younsu; Gao, Wei; Nyein, Hnin Yin Yin; Liaw, Tiffany Sun; Tai, Li-Chia; Ngo, Quynh P; Chao, Minghan; Zhao, Yingbo; Hettick, Mark; Cho, Gyoujin; Javey, Ali

2018-06-25

As recent developments in noninvasive biosensors spearhead the thrust toward personalized health and fitness monitoring, there is a need for high throughput, cost-effective fabrication of flexible sensing components. Toward this goal, we present roll-to-roll (R2R) gravure printed electrodes that are robust under a range of electrochemical sensing applications. We use inks and electrode morphologies designed for electrochemical and mechanical stability, achieving devices with uniform redox kinetics printed on 150 m flexible substrate rolls. We show that these electrodes can be functionalized into consistently high performing sensors for detecting ions, metabolites, heavy metals, and other small molecules in noninvasively accessed biofluids, including sensors for real-time, in situ perspiration monitoring during exercise. This development of robust and versatile R2R gravure printed electrodes represents a key translational step in enabling large-scale, low-cost fabrication of disposable wearable sensors for personalized health monitoring applications.

Industrial wastewater re-use: closure of water cycle in the main water consuming industries--the example of paper mills.

PubMed

Mauchauffee, S; Denieul, M-P; Coste, M

2012-01-01

Paper mill, chemistry, textile and food processing industries are high water consumers. Within the framework of the European project Aquafit4Use, the possibility to close the on-site water loop is studied. The aim is to find new technologies or innovative treatment trains to produce water that is 'fit for use' in the industrial process; an example of a paper mill is given. Laboratory-scale tests on nine technologies were carried out to determine the best suitable treatment train: anaerobic process (already on site) --> aerobic process (already on site) --> Flexible Fibre Filter Module --> softening --> nanofiltration --> evapoconcentration or ozonation on nanofiltration (NF) concentrate. This treatment train is currently compared on site at pilot scale to another treatment train including some modifications on the existing on-site biological treatment: anaerobic process --> softening --> membrane bioreactor --> nanofiltration --> evapoconcentration or ozonation of NF concentrate.

Calculation of a vacuum system of the installation for cleaning the surface of metal rolling by a cathode spot of a vacuum arc

NASA Astrophysics Data System (ADS)

Kuznetsov, V. G.; Kurbanov, T. A.; Kostrin, D. K.

2017-07-01

In this work are presented the installations for cleaning the surface of rolled products (wire and ribbon) from scale and technological lubricant with gateway systems of open type. The calculation of gateway devices and the optimal selection of pumping systems are shown.

A pilot-scale nonwoven roll goods manufacturing process reduces microbial burden to pharmacopeia acceptance levels for nonsterile hygiene applications

USDA-ARS?s Scientific Manuscript database

A total of seven source fiber types were selected for use in the manufacturing of nonwoven roll goods: polyester; polypropylene; rayon; greige cotton from two sources; mechanically cleaned greige cotton; and scoured and bleached cotton. The microbial burden of each source fiber was measured as a pr...

Future of the particle replication in nonwetting templates (PRINT) technology.

PubMed

Xu, Jing; Wong, Dominica H C; Byrne, James D; Chen, Kai; Bowerman, Charles; DeSimone, Joseph M

2013-06-24

Particle replication in nonwetting templates (PRINT) is a continuous, roll-to-roll, high-resolution molding technology which allows the design and synthesis of precisely defined micro- and nanoparticles. This technology adapts the lithographic techniques from the microelectronics industry and marries these with the roll-to-roll processes from the photographic film industry to enable researchers to have unprecedented control over particle size, shape, chemical composition, cargo, modulus, and surface properties. In addition, PRINT is a GMP-compliant (GMP=good manufacturing practice) platform amenable for particle fabrication on a large scale. Herein, we describe some of our most recent work involving the PRINT technology for application in the biomedical and material sciences. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fabrication of flexible oriented magnetic thin films with large in-plane uniaxial anisotropy by roll-to-roll nanoimprint lithography

NASA Astrophysics Data System (ADS)

Thantirige, Rukshan M.; John, Jacob; Pradhan, Nihar R.; Carter, Kenneth R.; Tuominen, Mark T.

2016-06-01

Here, we report wafer scale fabrication of densely packed Fe nanostripe-based magnetic thin films on a flexible substrate and their magnetic anisotropy properties. We find that Fe nanostripes exhibit large in-plane uniaxial anisotropy and nearly square hysteresis loops with energy products (BHmax) exceeding 3 MGOe at room temperature. High density Fe nanostripes were fabricated on 70 nm flexible polyethylene terephthalate (PET) gratings, which were made by a roll-to-roll (R2R) UV nanoimprint lithography technique. We observed large in-plane uniaxial anisotropies along the long dimension of nanostripes that can be attributed to the shape. Temperature dependent hysteresis measurements confirm that the magnetization reversal is driven by non-coherent rotation reversal processes.

Effect of black rice husk ash on the physical and rheological properties of bitumen

NASA Astrophysics Data System (ADS)

Romastarika, Raissa; Jaya, Ramadhansyah Putra; Yaacob, Haryati; Nazri, Fadzli Mohamed; Agussabti, Ichwana, Jayanti, Dewi Sri

2017-08-01

Black rice husk ash (BRHA) waste product is inexpensive and can be obtained from rice mills. Reuse of waste product is ideal to reduce pollution, because disposal is decreased or eliminated. The commercial value of BRHA has increased, and it is suitable for use in road construction. In this study, BRHA waste was ground using a grinding ball mill for 120 min to form fine powder. BRHA was then sieved to less than 75 µm. At the laboratory, BRHA was mixed with bitumen to replace 2%, 4%, and 6% of the total weight, whereas 0% represented the control sample. The penetration, softening point, dynamic shear rheometer (DSR) and rolling thin film oven (RTFO) were investigated in this study. Results showed that bitumen became harder, whereas the rate of penetration decreased when the replacement amount of BRHA increased. Softening point test of bitumen also revealed an increase. The short-term aging test revealed that modification of bitumen could relieve the effect of aging. BRHA waste added into bitumen improved the performance of bitumen. Therefore, the usage of BRHA could help improve the performance of road pavement and reduce the rutting effect.

Capability of Rolling Efficiency for 100M High-Speed Rails

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Howard

2014-03-22

OG Technologies, Inc. (OGT), along with its academic and industrial partners, proposes this CORE project for the Capability of Rolling Efficiency for 100m high-speed rails. The goal is to establish the competitive advantage, and thus the sustainability of the US-based rail manufacturers by greatly enhanced efficiency through innovative in-line metrology technology, in-depth process knowledge, and advanced process control to overcome detrimental factors such as higher labor costs that are saddling the US manufacturing sector. This Phase I project was carried out by an industrial-academia team over 9 months. The R&D team successfully completed all technical tasks and accomplished the objectivesmore » for the Phase I. In addition to the technical efforts, the introductory information of this project as well as anticipated progress was disseminated to steel mills interested in the project. The Phase I project has established the technical and commercial basis for additional development. There are needs to further completing the in-line sensing capability, deepening the capability of metamodeling, and supporting the process monitoring and control. The R&D team plans to submit a Phase II proposal based on the findings.« less

Efficient anti-corrosive coating of cold-rolled steel in a seawater environment using an oil-based graphene oxide ink.

PubMed

Singhbabu, Y N; Sivakumar, B; Singh, J K; Bapari, H; Pramanick, A K; Sahu, Ranjan K

2015-05-07

We report the production of an efficient anti-corrosive coating of cold-rolled (CR) steel in a seawater environment (∼3.5 wt% NaCl aqueous solution) using an oil-based graphene oxide ink. The graphene oxide was produced by heating Aeschynomene aspera plant as a carbon source at 1600 °C in an argon atmosphere. The ink was prepared by cup-milling the mixture of graphene oxide and sunflower oil for 10 min. The coating of ink on the CR steel was made using the dip-coating method, followed by curing at 350 °C for 10 min in air atmosphere. The results of the potentiodynamic polarization show that the corrosion rate of bare CR steel decreases nearly 10,000-fold by the ink coating. Furthermore, the salt spray test results show that the red rusting in the ink-coated CR steel is initiated after 100 h, in contrast to 24 h and 6 h in the case of oil-coated and bare CR steel, respectively. The significant decrease in the corrosion rate by the ink-coating is discussed based on the impermeability of graphene oxide to the corrosive ions.

Infant rolling abilities--the same or different 20 years after the back to sleep campaign?

PubMed

Darrah, Johanna; Bartlett, Doreen J

2013-05-01

To compare the order and age of emergence of rolling prone to supine and supine to prone before the introduction of back to sleep guidelines and 20 years after their introduction. The original normative data for the Alberta Infant Motor Scale (AIMS) were collected just prior to the introduction of back to sleep guidelines in 1992. Currently these norms are being re-evaluated. Data of rolling patterns of infants 36 weeks of age or younger from the original sample (n=1114) and the contemporary sample (n=351) were evaluated to compare the sequence of appearance of prone to supine and supine to prone rolls (proportion of infants passing each roll) and the ages of emergence (estimated age when 50% of infants passed each roll). The sequence of emergence and estimated age of appearance of both rolling directions were similar between the two time periods. The introduction of the supine sleep position to reduce the prevalence of Sudden Infant Death Syndrome (SIDS) has not altered the timing or sequence of infant rolling abilities. This information is valuable to health care providers involved in the surveillance of infants' development. Original normative age estimates for these two motor abilities are still appropriate. Copyright © 2012 Elsevier Ltd. All rights reserved.

On global gravity anomalies and two-scale mantle convection

NASA Technical Reports Server (NTRS)

Marsh, B. D.; Marsh, J. G.

1976-01-01

The two-scale model of mantle convection developed by Richter and Parsons (1975) predicts that if the depth of the convective layer is about 600 km, then for a plate moving at 10 cm/yr, longitudinal convective rolls will be produced in about 50 million years, and the strike of these rolls indicates the direction of motion of the plate relative to the upper mantle. The paper tests these predictions by examining a new global free air gravity model complete to the 30th degree and order. The free air gravity map developed shows a series of linear positive and negative anomalies (with transverse wavelengths of about 2000 km) spanning the Pacific Ocean, crossing the Pacific rise and striking parallel to the Hawaiian seamounts. It is suggested that the pattern of these anomalies may indicate the presence of longitudinal convective rolls beneath the Pacific plates, a result which tends to support the predictions of Richter and Parsons.

Comparison Between Different Processing Schedules for the Development of Ultrafine-Grained Dual-Phase Steel

NASA Astrophysics Data System (ADS)

Karmakar, Anish; Sivaprasad, S.; Nath, S. K.; Misra, R. D. K.; Chakrabarti, Debalay

2014-05-01

A comparative study was carried out on the development of ultrafine-grained dual-phase (DP) (ferrite-martensite) structures in a low-carbon microalloyed steel processed using two thermomechanical processing routes, (i) intercritical deformation and (ii) warm-deformation and intercritical annealing. The samples were deformed using Gleeble3500® simulator, maintaining a constant total strain ( ɛ = 1) and strain rate ( = 1/s). Evolution of microstructure and micro-texture was investigated by SEM, TEM, and EBSD. Ultrafine-grained DP structures could be formed by careful selection of deformation temperature, T def (for intercritical deformation) or annealing temperature, T anneal (for warm-deformation and annealing). Overall, the ferrite grain sizes ranged from 1.5 to 4.0 μm, and the sizes and fractions of the uniformly distributed fine-martensitic islands ranged from 1.5 to 3.0 μm and 15 to 45 pct, respectively. Dynamic strain-induced austenite-to-ferrite transformation followed by continuous (dynamic) recrystallization of the ferrite dictated the grain refinement during intercritical deformation, while, continuous (static) recrystallization by pronounced recovery dictated the grain refinement during the warm-deformation and the annealing. Regarding intercritical deformation, the samples cooled to T def indicated finer grain size compared with the samples heated to T def, which are explained in terms of the effects of strain partitioning on the ferrite and the heating during deformation. Alpha-fiber components dominated the texture in all the samples, and the fraction of high-angle boundaries (with >15 deg misorientation) increased with the increasing T def or T anneal, depending on the processing schedule. Fine carbide particles, microalloyed precipitates and austenitic islands played important roles in defining the mechanism of grain refinement that involved retarding conventional ferrite recrystallization and ferrite grain growth. With regard to the intercritical deformation, warm-deformation followed by annealing is a simpler process to control in the rolling mill; however, the need for high-power rolling mill and controlled annealing facility imposes industrial challenges.

Cartan gravity, matter fields, and the gauge principle

NASA Astrophysics Data System (ADS)

Westman, Hans F.; Zlosnik, Tom G.

2013-07-01

Gravity is commonly thought of as one of the four force fields in nature. However, in standard formulations its mathematical structure is rather different from the Yang-Mills fields of particle physics that govern the electromagnetic, weak, and strong interactions. This paper explores this dissonance with particular focus on how gravity couples to matter from the perspective of the Cartan-geometric formulation of gravity. There the gravitational field is represented by a pair of variables: (1) a 'contact vector' VA which is geometrically visualized as the contact point between the spacetime manifold and a model spacetime being 'rolled' on top of it, and (2) a gauge connection AμAB, here taken to be valued in the Lie algebra of SO(2,3) or SO(1,4), which mathematically determines how much the model spacetime is rotated when rolled. By insisting on two principles, the gauge principle and polynomial simplicity, we shall show how one can reformulate matter field actions in a way that is harmonious with Cartan's geometric construction. This yields a formulation of all matter fields in terms of first order partial differential equations. We show in detail how the standard second order formulation can be recovered. In particular, the Hodge dual, which characterizes the structure of bosonic field equations, pops up automatically. Furthermore, the energy-momentum and spin-density three-forms are naturally combined into a single object here denoted the spin-energy-momentum three-form. Finally, we highlight a peculiarity in the mathematical structure of our first-order formulation of Yang-Mills fields. This suggests a way to unify a U(1) gauge field with gravity into a SO(1,5)-valued gauge field using a natural generalization of Cartan geometry in which the larger symmetry group is spontaneously broken down to SO(1,3)×U(1). The coupling of this unified theory to matter fields and possible extensions to non-Abelian gauge fields are left as open questions.

Survey and comparison of sleep quality among fixed and changing shift staff in a steel factory in Tehran, Iran.

PubMed

Mohammadian, Farugh; Abbasinia, Marzieh; Rahmani, Abdolrasoul; Monazzam, Mohammad Reza; Asghari, Mehdi; Ahmadnezhad, Iman; Asadi, Ali

2013-01-01

Given the hazardous nature of the work in steel factories and that the staff has to deal with hazardous equipment and machines, improper sleep quality and drowsiness among the works tackles performance and boosts rate of job accidents. This study is aimed to survey the quality of sleep and sleepiness status and the pertinent factors among the workers in a rolling mill and a steel production company in Tehran, Iran. In a Cross-Sectional study 2011, 180 workers were selected randomly from a rolling mill and a steel production company in Tehran. A questionnaire was designed to collect demographic data and variables of work condition. Pitersborg's sleep quality questionnaire was used to survey quality and problems of Participants' sleep. Epworth Sleepiness questionnaire was used to deals with sleepiness during work, studying, watching TV, or during time spent in public. Average score of sleep quality for the fixed shift staff and changing shift staff were 7.5±2.82 and 8.49±2.95 respectively. Surveys of sleep quality for the two groups of the participants based on T-test showed a significant difference between the two groups so that the changing shift staff group suffered poorer sleep quality (p=0.03). Comparison of average drowsiness scores between the two groups of participants based on Mann-Whitney test showed no significant difference (p>0.005). Chi square test showed a significant difference between severity of drowsiness and type of working shift (p =0.028 and 0.009). Staff in revolving shifts suffers poor sleep quality comparing with staff with fixed working shift. Moreover, type of working shift greatly affects severity of drowsiness as staff at different work shift experienced different level of sleepiness. It is essential to survey sleep disorder of the staff in the industry and pay more emphasis on sleep disorder epidemic in other fields of industry.

Mineral scale management. Part 1, Case studies

Treesearch

Peter W. Hart; Alan W. Rudie

2006-01-01

Mineral scale increases operating costs, extends downtime, and increases maintenance requirements. This paper presents several successful case studies detailing how mills have eliminated scale. Cases presented include calcium carbonate scale in a white liquor strainer, calcium oxalate scale in the D0 stage of the bleach plant, enzymatic treatment of brown stock to...

Tree species associations of Pinus echinata mill. over a large-scale sampling regime on the interior highlands of Arkansas

Treesearch

James F., Jr. Rosson

2007-01-01

The Interior Highlands physiographic province of Arkansas is considered the ecological center of the geographic distribution of shortleaf pine (Pinus echinata Mill.). I used data from the U.S. Forest Service, Forest Inventory and Analysis (FIA) program to identify the major tree species associates of P. echinata across this 66,700-...

Systematic comparison of mechanical and thermal sludge disintegration technologies.

PubMed

Wett, B; Phothilangka, P; Eladawy, A

2010-06-01

This study presents a systematic comparison and evaluation of sewage sludge pre-treatment by mechanical and thermal techniques. Waste activated sludge (WAS) was pre-treated by separate full scale Thermo-Pressure-Hydrolysis (TDH) and ball milling facilities. Then the sludge was processed in pilot-scale digestion experiments. The results indicated that a significant increase in soluble organic matter could be achieved. TDH and ball milling pre-treatment could offer a feasible treatment method to efficiently disintegrate sludge and enhance biogas yield of digestion. The TDH increased biogas production by ca. 75% whereas ball milling allowed for an approximately 41% increase. The mechanisms of pre-treatment were investigated by numerical modeling based on Anaerobic Digestion Model No. 1 (ADM1) in the MatLab/SIMBA environment. TDH process induced advanced COD-solubilisation (COD(soluble)/COD(total)=43%) and specifically complete destruction of cell mass which is hardly degradable in conventional digestion. While the ball mill technique achieved a lower solubilisation rate (COD(soluble)/COD(total)=28%) and only a partial destruction of microbial decay products. From a whole-plant prospective relevant release of ammonia and formation of soluble inerts have been observed especially from thermal hydrolysis. Copyright 2009 Elsevier Ltd. All rights reserved.

Preparation of autogenous bone grafts in two different bone mills.

PubMed

Erpenstein, H; Diedrich, P; Borchard, R

2001-12-01

The purpose of this study was to evaluate the performance of two bone mills (R Quetin Bone Mill and Micro Knochenmühle, Aesculap) for the grinding of autogenous bone (intraoral, cortical) according to the following criteria: (1) loss of bone during the grinding process, (2) particle size of the chips, (3) variability in chip size, (4) technical handling, and (5) cost-benefit ratio. The amount of material loss was determined by harvesting 30 bone cores from the mandibular symphysis of a pig. Each specimen was weighed before and after the grinding procedure on scales with an accuracy of 0.1 mg. The size and variability of the bone particles were determined histomorphometrically. Twenty-seven bone specimens from different patients were analyzed. Eight were ground with the Aesculap and 12 with the Quetin mill. Seven specimens harvested with a Brånemark implant bur served as controls. A histologic section was prepared from each specimen, and 10 bone particles per section were subjected to histomorphometric analysis. The Quetin mill was superior in all points to the Aesculap mill for the requirements of a periodontal practice.

Comparison of characteristics of hydroxyapatite powders synthesized from cuttlefish bone via precipitation and ball milling techniques

NASA Astrophysics Data System (ADS)

Faksawat, K.; Kaewwiset, W.; Limsuwan, P.; Naemchanthara, K.

2017-09-01

The aim of this work was to compare characteristics of hydroxyapatite synthesized by precipitation and ball milling techniques. The cuttlefish bone powder was a precursor in calcium source and the di ammonium hydrogen orthophosphate powders was a precursor in phosphate source. The hydroxyapatite was synthesized by the both techniques such as precipitation and ball milling techniques. The phase formation, chemical structure and morphology of the both hydroxyapatite powders have been examined by X-ray diffractometer (XRD), Fourier transform infrared spectroscope (FTIR) and field emission scanning electron microscope (FESEM), respectively. The results show that the hydroxyapatite synthesized by precipitation technique formed hydroxyapatite phase slower than the hydroxyapatite synthesized by ball milling technique. The FTIR results show the chemical structures of sample in both techniques are similar. The morphology of the hydroxyapatite from the both techniques were sphere like shapes and particle size was about in nano scale. The average particle size of the hydroxyapatite by ball milling technique was less than those synthesized by precipitation technique. This experiment indicated that the ball milling technique take time less than the precipitation technique in hydroxyapatite synthesis.

Scalable fabrication of perovskite solar cells

DOE PAGES

Li, Zhen; Klein, Talysa R.; Kim, Dong Hoe; ...

2018-03-27

Perovskite materials use earth-abundant elements, have low formation energies for deposition and are compatible with roll-to-roll and other high-volume manufacturing techniques. These features make perovskite solar cells (PSCs) suitable for terawatt-scale energy production with low production costs and low capital expenditure. Demonstrations of performance comparable to that of other thin-film photovoltaics (PVs) and improvements in laboratory-scale cell stability have recently made scale up of this PV technology an intense area of research focus. Here, we review recent progress and challenges in scaling up PSCs and related efforts to enable the terawatt-scale manufacturing and deployment of this PV technology. We discussmore » common device and module architectures, scalable deposition methods and progress in the scalable deposition of perovskite and charge-transport layers. We also provide an overview of device and module stability, module-level characterization techniques and techno-economic analyses of perovskite PV modules.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Zhen; Klein, Talysa R.; Kim, Dong Hoe

Perovskite materials use earth-abundant elements, have low formation energies for deposition and are compatible with roll-to-roll and other high-volume manufacturing techniques. These features make perovskite solar cells (PSCs) suitable for terawatt-scale energy production with low production costs and low capital expenditure. Demonstrations of performance comparable to that of other thin-film photovoltaics (PVs) and improvements in laboratory-scale cell stability have recently made scale up of this PV technology an intense area of research focus. Here, we review recent progress and challenges in scaling up PSCs and related efforts to enable the terawatt-scale manufacturing and deployment of this PV technology. We discussmore » common device and module architectures, scalable deposition methods and progress in the scalable deposition of perovskite and charge-transport layers. We also provide an overview of device and module stability, module-level characterization techniques and techno-economic analyses of perovskite PV modules.« less

Experimental and analytical studies of advanced air cushion landing systems

NASA Technical Reports Server (NTRS)

Lee, E. G. S.; Boghani, A. B.; Captain, K. M.; Rutishauser, H. J.; Farley, H. L.; Fish, R. B.; Jeffcoat, R. L.

1981-01-01

Several concepts are developed for air cushion landing systems (ACLS) which have the potential for improving performance characteristics (roll stiffness, heave damping, and trunk flutter), and reducing fabrication cost and complexity. After an initial screening, the following five concepts were evaluated in detail: damped trunk, filled trunk, compartmented trunk, segmented trunk, and roll feedback control. The evaluation was based on tests performed on scale models. An ACLS dynamic simulation developed earlier is updated so that it can be used to predict the performance of full-scale ACLS incorporating these refinements. The simulation was validated through scale-model tests. A full-scale ACLS based on the segmented trunk concept was fabricated and installed on the NASA ACLS test vehicle, where it is used to support advanced system development. A geometrically-scaled model (one third full scale) of the NASA test vehicle was fabricated and tested. This model, evaluated by means of a series of static and dynamic tests, is used to investigate scaling relationships between reduced and full-scale models. The analytical model developed earlier is applied to simulate both the one third scale and the full scale response.

Shock compression response of cold-rolled Ni/Al multilayer composites

NASA Astrophysics Data System (ADS)

Specht, Paul E.; Weihs, Timothy P.; Thadhani, Naresh N.

2017-01-01

Uniaxial strain, plate-on-plate impact experiments were performed on cold-rolled Ni/Al multilayer composites and the resulting Hugoniot was determined through time-resolved measurements combined with impedance matching. The experimental Hugoniot agreed with that previously predicted by two dimensional (2D) meso-scale calculations [Specht et al., J. Appl. Phys. 111, 073527 (2012)]. Additional 2D meso-scale simulations were performed using the same computational method as the prior study to reproduce the experimentally measured free surface velocities and stress profiles. These simulations accurately replicated the experimental profiles, providing additional validation for the previous computational work.

Scaling the Geologic Past

ERIC Educational Resources Information Center

Gerritts, Mary

1975-01-01

Describes construction of a Geologic Time Scale on a 100 foot roll of paper and suggests activities concerning its use. Includes information about fossils and suggestions for conducting a fossil field trip with students. (BR)

Aerodynamic Characteristics of a 0.5-Scale Model of the Fairchild XSAM-N-2 Lark Missile at High Subsonic Speeds

NASA Technical Reports Server (NTRS)

Martin, Andrew; Hunter, Harlo A.

1949-01-01

An investigation was conducted to determine the longitudinal- and lateral-stability characteristics of a 0.5-scale moue1 of the Fairchild Lark missile, The model was tested with 0 deg and with 22.5 deg of roll. Three horizontal wings having NACA 16-009, 16-209, and 64A-209 sections were tested. Pressures were measured on both pointed and blunt noses. The wind-tunnel-test data indicate that rolling the missile 22.5 deg. had no serious effect on the static longitudinal stability. The desired maneuvering acceleration could not be attained with any of the horizontal wings tested, even with the horizontal wing flaps deflected 50 deg. The flaps on the 64A-209 wing (with small trailing-edge angles and flat sides) were effective at all flap deflections, while the flaps on the 16-series wings (with large trailing-edge angles) lost effectiveness at small flap deflections. The data showed that rolling moment existed when the vertical wing flaps were deflected with the model at other than zero angle of attack. A similar rolling moment probably would be found . with the horizontal wing flaps deflected and the model yawed.

Rolling viscous drops on a non-wettable surface containing both micro- and macro-scale roughness

NASA Astrophysics Data System (ADS)

Abolghasemibizaki, Mehran; Robertson, Connor J.; Fergusson, Christian P.; McMasters, Robert L.; Mohammadi, Reza

2018-02-01

It has previously been shown that when a liquid drop of high viscosity is placed on a non-wettable inclined surface, it rolls down at a constant descent velocity determined by the balance between viscous dissipation and the reduction rate of its gravitational potential energy. Since increasing the roughness of the surface boosts its non-wetting property, the drop should move faster on a surface structured with macrotextures (ribbed surface). Such a surface was obtained from a superhydrophobic soot coating on a solid specimen printed with an extruder-type 3D printer. The sample became superoleophobic after a functionalization process. The descent velocity of glycerol drops of different radii was then measured on the prepared surface for varied tilting angles. Our data show that the drops roll down on the ribbed surface approximately 27% faster (along the ridges) than on the macroscopically smooth counterpart. This faster velocity demonstrates that ribbed surfaces can be promising candidates for drag-reduction and self-cleaning applications. Moreover, we came up with a modified scaling model to predict the descent velocity of viscous rolling drops more accurately than what has previously been reported in the literature.

A fault diagnosis scheme for rolling bearing based on local mean decomposition and improved multiscale fuzzy entropy

NASA Astrophysics Data System (ADS)

Li, Yongbo; Xu, Minqiang; Wang, Rixin; Huang, Wenhu

2016-01-01

This paper presents a new rolling bearing fault diagnosis method based on local mean decomposition (LMD), improved multiscale fuzzy entropy (IMFE), Laplacian score (LS) and improved support vector machine based binary tree (ISVM-BT). When the fault occurs in rolling bearings, the measured vibration signal is a multi-component amplitude-modulated and frequency-modulated (AM-FM) signal. LMD, a new self-adaptive time-frequency analysis method can decompose any complicated signal into a series of product functions (PFs), each of which is exactly a mono-component AM-FM signal. Hence, LMD is introduced to preprocess the vibration signal. Furthermore, IMFE that is designed to avoid the inaccurate estimation of fuzzy entropy can be utilized to quantify the complexity and self-similarity of time series for a range of scales based on fuzzy entropy. Besides, the LS approach is introduced to refine the fault features by sorting the scale factors. Subsequently, the obtained features are fed into the multi-fault classifier ISVM-BT to automatically fulfill the fault pattern identifications. The experimental results validate the effectiveness of the methodology and demonstrate that proposed algorithm can be applied to recognize the different categories and severities of rolling bearings.

Dynamic stability test results on an 0.024 scale B-1 air vehicle

NASA Technical Reports Server (NTRS)

Beeman, R. R.

1972-01-01

Dynamic longitudinal and lateral-directional stability characteristics of the B-1 air vehicle were investigated in three wind tunnels at the Langley Research Center. The main rotary derivatives were obtained for an angle of attack range of -3 degrees to +16 degrees for a Mach number range of 0.2 to 2.16. Damping in roll data could not be obtained at the supersonic Mach numbers. The Langley 7 x 10 foot high speed tunnel, the 8 foot transonic pressure tunnel, and the 4 foot Unitary Plan wind tunnel were the test sites. An 0.024 scale light-weight model was used on a forced oscillation type balance. Test Reynolds number varied from 474,000/ft to 1,550,000/ft. through the Mach number range tested. The results showed that the dynamic stability characteristics of the model in pitch and roll were generally satisfactory up to an angle attack of about +6 degrees. In the wing sweep range from 15 to 25 degrees the positive damping levels in roll deteriorated rapidly above +2 degrees angle of attack. This reduction in roll damping is believed to be due to the onset of separation over the wing as stall is approached.

Use of agar agar stabilized milled zero-valent iron particles for in situ groundwater remediation

NASA Astrophysics Data System (ADS)

Schmid, Doris; Velimirović, Milica; Wagner, Stephan; Micić Batka, Vesna; von der Kammer, Frank; Hofmann, Thilo

2015-04-01

A major obstacle for use of nanoscale zero-valent iron (nZVI) particles as a nontoxic material for effective in situ degradation of chlorinated aliphatic hydrocarbons (CAHs) is the high production cost. For that reason, submicro-scale milled zero-valent iron particles were recently developed (milled ZVI, UVR-FIA, Germany) by grinding macroscopic raw materials of elementary iron as a cheaper alternative to products produced by solid-state reduction. However, milled ZVI particles tend to aggregate and due to the rather large particle size (d50= 11.9 µm) also rapidly sediment. To prevent aggregation and consequently sedimentation of milled ZVI particles and therefore improve the mobility after in situ application, the use of a stabilizer is considered in literature as a most promising option. In this study, milled ZVI particles (1 g L-1 of particle concentration) were stabilized by environmentally friendly polymer agar agar (>0.5 g L-1), which had a positive impact on the milled ZVI stability. Sedimentation rate was significantly decreased by increasing the suspension viscosity. Column transport experiments were performed for bare and agar agar stabilized milled ZVI particles in commercially available fine grained quartz sand (DORSILIT® Nr.8, Gebrüder Dorfner GmbH Co, Germany) and different porous media collected from brownfields. The experiments were carried out under field relevant injection conditions of 100 m d-1. The maximal travel distance (LT) of less than 10 cm was determined for non-stabilized suspension in fine grained quartz sand, while agar agar (1 g L-1) stabilized milled ZVI suspension revealed LT of 12 m. Similar results were observed for porous media from brownfields showing that mobility of agar agar stabilized particle suspensions was significantly improved compared to bare particles. Based on the mobility data, agar agar stabilized milled zero-valent iron particles could be used for in situ application. Finally, lab-scale batch degradation experiments were performed to determine the impact of agar agar on the reactivity of milled ZVI and investigate the apparent corrosion rate of particles by quantifying the hydrogen gas generated by anaerobic corrosion of milled ZVI. The results indicate that agar agar had a positive impact on the milled ZVI stability and mobility, however adverse impact on the reactivity towards trichloroethene (TCE) was observed compared to the non-stabilized material. On the other hand, this study shows that the apparent corrosion rate of non-stabilized and agar agar stabilized milled ZVI particles is in the same order of magnitude. These data indicate that the dechlorination pathway of TCE by agar agar stabilized milled ZVI particles is possibly impacted by blocking of the reactive sites and not hydrogen revealed during particles corrosion. Finally, calculated longevity of the particles based on the apparent corrosion rate is significantly prolonged compared to the longevity of the nZVI particles reported in previous studies. This research receives funding from the European Union's Seventh Framework Programme FP7/2007-2013 under grant agreement n°309517.

Investigation of pattern transfer to piezoelectric jetted polymer using roll-to-roll nanoimprint lithography

NASA Astrophysics Data System (ADS)

Menezes, Shannon John

Nanoimprint Lithography (NIL) has existed since the mid 1990s as a proven concept of creating micro- and nanostructures using direct mechanical pattern transfer. Initially seen as a viable option to replace conventional lithography methods, the lack of technology to support large-scale manufacturing using NIL has motivated researchers to explore the application of NIL to create a better, more cost-efficient process with the ability to integrate NIL into a mass manufacturing system. One such method is the roll-to-roll process, similar to that used in printing presses of newspapers and plastics. This thesis is an investigation to characterize polymer deposition using a piezoelectric jetting head and attempt to create micro- and nanostructures on the polymer using R2RNIL technique.

Low-temperature roll-to-roll coating procedure of dye-sensitized solar cell photoelectrodes on flexible polymer-based substrates

NASA Astrophysics Data System (ADS)

Tinguely, Jean-Claude; Solarska, Renata; Braun, Artur; Graule, Thomas

2011-04-01

A new approach for the large-scale production of flexible photoelectrodes for dye-sensitized solar cells (DSSCs) is presented by roll-to-roll coating of a titanium dioxide nanodispersion containing the block copolymer 'Pluronic®' (PEOx-PPOy-PEOx, PEO: poly(ethylene oxide), PPO: poly(propylene oxide)). Functional DSSCs were assembled and the different coating procedures compared with respect to their solar power conversion efficiency. It is shown that the binder 'Pluronic' can be removed at processing temperatures as low as 140 °C, thus aiding achievement of sufficient adhesion to the ITO-PET support, higher porosity of the TiO2 layer and decreased crack appearance. Further optimization of this method is particularly promising when combined with other known low-temperature methods.

''Cloud in Cell'' technique applied to the roll up of vortex sheets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baker, G.R.

The problem of the roll up of a two dimensional vortex sheet generated by a wing in an ideal fluid is phrased in terms of the streamfunction and the vortex sheet strength. A numerical method is used to calculate the time evolution of the vortex sheet by adapting the ''Cloud In Cell'' technique introduced in solving many particle simulations in plasma physics (see J. P. Christiansen, J. Computational Physics 13 (1973)). Two cases are considered for the initial distribution of circulation, one corresponding to an elliptically loaded wing and the other simulating the wing with a flap deployed. Results indicatemore » that small scale behaviour plays an important part in the roll up. Typically, small scale perturbations result in small structures which evolve into ever increasing larger structures by vortex amalgamation. Conclusions are given from a number of tests exploring the validity of the method. Briefly, small scale perturbations are introduced artificially by the grid; but once the process of vortex amalgamation is well underway, the emerging large scale behaviour is relatively insensitive to the precise details of the initial perturbations. Since clearly defined structures result from the application of this method, it promises to aid considerably in understanding the behaviour of vortex wakes.« less

Morphology and thermal stability of nano titanium dioxide filled natural rubber prepared by latex mixing method

NASA Astrophysics Data System (ADS)

Hayeemasae, N.; Surya, I.; Ismail, H.

2018-02-01

This paper deals with the morphology and thermal stability of nano Titanium Dioxide (TiO2) filled natural rubber composites. This study also suggests a new method of incorporating TiO2. Aqueous dispersions of nano TiO2at the loadings of 0, 2, 4, 6 and 8 phr were dispersed in natural rubber latex, the resulting compounds were then dried prior to mixing it with other ingredients on a two-roll mill. By applying this technique, the homogeneity of the compound is significantly improved. This can be clearly seen from the morphology observed. Adding TiO2 results in shifting the decomposition temperature and char residue irrespective of the loadings of nano TiO2.

Substrate milling pretreatment as a key parameter for Solid-State Anaerobic Digestion optimization.

PubMed

Motte, J-C; Escudié, R; Hamelin, J; Steyer, J-P; Bernet, N; Delgenes, J-P; Dumas, C

2014-12-01

The effect of milling pretreatment on performances of Solid-State Anaerobic Digestion (SS-AD) of raw lignocellulosic residue is still controverted. Three batch reactors treating different straw particle sizes (milled 0.25 mm, 1 mm and 10 mm) were followed during 62 days (6 sampling dates). Although a fine milling improves substrate accessibility and conversion rate (up to 30% compared to coarse milling), it also increases the risk of media acidification because of rapid and high acids production during fermentation of the substrate soluble fraction. Meanwhile, a gradual adaptation of microbial communities, were observed according to both reaction progress and methanogenic performances. The study concluded that particle size reduction affected strongly the performances of the reaction due to an increase of substrate bioaccessibility. An optimization of SS-AD processes thanks to particle size reduction could therefore be applied at farm or industrial scale only if a specific management of the soluble compounds is established. Copyright © 2014 Elsevier Ltd. All rights reserved.

Processing mill scale study data on a type 650 electronic machine.

Treesearch

Floyd A. Johnson

1956-01-01

During April 1956, about 20,000 boards from 210 white fir and 290 western hemlock logs were measured at a lumber mill in western Washington. A magnetic drum, data-processing machine (type 650) was then used to calculate board-feet volumes by lumber grade for each log, and average board-foot volumes by lumber grade for each log diameter-class within log grades and...

Ponderosa pine lumber recovery in Lakeview, Oregon area.

Treesearch

E.E. Matson

1955-01-01

During January 1955, a study was made at the American Forest Products Corporation mill in Lakeview, Oregon, to determine the grades of lumber that can be expected from ponderosa pine timber grown in the Lakeview area of Oregon. All logs cut for a full week at this mill were scaled and graded and all the lumber produced was graded and tallied on the green chain by...

The early mills, railroads, and logging camps of the Crossett Lumber Company

Treesearch

O.H. Doogie Darling; Don C. Bragg

2008-01-01

Form the earliest small-scale logging and milling operations to the multinational conglomerates of today, the timber industry has long shaped the social and economic history of the southern United States. Nowhere is this more true than in Crossett, Arkansas. Born of the axe and saw, oxen and steam engines, and nurtured by the railroad during its infancy, Crossett was...

Investigation at low speeds of the effect of aspect ratio and sweep on rolling stability derivatives of untapered wings

NASA Technical Reports Server (NTRS)

Goodman, Alex; Fisher, Lewis R.

1949-01-01

A low scale wind tunnel investigation was conducted in rolling flow to determine the effects of aspect ratio and sweep (when varied independently) on the rolling stability derivatives for a series of untapered wings. Test results indicate that when the aspect ratio was held constant, an increase in the sweepback angle caused a significant reduction in the damping in roll at low lift coefficients for only the higher aspect ratios that were tested. This result was in agreement with available swept wing theory which indicated no effect of sweep for aspect ratios near zero. The result of the linear theory that the damping in roll is independent of lift coefficient and that the yawing moment and lateral force due to rolling are directly proportional to the lift coefficient was found to be valid for only a very limited lift coefficient range when the wings were highly swept. For such wings, the damping was found to increase in magnitude and the yawing moment due to rolling, to change from negative to positive at moderate lift coefficients. The effect of wing tip suction, not acounted for by present theory, was found to be very important with regard to the yawing moment due to rolling, particularly for low aspect ratio swept wings. An empirical means of correcting present theory for the effect of tip suction is suggested.

Manufacturing Demonstration Facility: Roll-to-Roll Processing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Datskos, Panos G; Joshi, Pooran C; List III, Frederick Alyious

This Manufacturing Demonstration Facility (MDF)e roll-to-roll processing effort described in this report provided an excellent opportunity to investigate a number of advanced manufacturing approaches to achieve a path for low cost devices and sensors. Critical to this effort is the ability to deposit thin films at low temperatures using nanomaterials derived from nanofermentation. The overarching goal of this project was to develop roll-to-roll manufacturing processes of thin film deposition on low-cost flexible substrates for electronics and sensor applications. This project utilized ORNL s unique Pulse Thermal Processing (PTP) technologies coupled with non-vacuum low temperature deposition techniques, ORNL s clean roommore » facility, slot dye coating, drop casting, spin coating, screen printing and several other equipment including a Dimatix ink jet printer and a large-scale Kyocera ink jet printer. The roll-to-roll processing project had three main tasks: 1) develop and demonstrate zinc-Zn based opto-electronic sensors using low cost nanoparticulate structures manufactured in a related MDF Project using nanofermentation techniques, 2) evaluate the use of silver based conductive inks developed by project partner NovaCentrix for electronic device fabrication, and 3) demonstrate a suite of low cost printed sensors developed using non-vacuum deposition techniques which involved the integration of metal and semiconductor layers to establish a diverse sensor platform technology.« less

Engineering nanoscale surface features to sustain microparticle rolling in flow.

PubMed

Kalasin, Surachate; Santore, Maria M

2015-05-26

Nanoscopic features of channel walls are often engineered to facilitate microfluidic transport, for instance when surface charge enables electro-osmosis or when grooves drive mixing. The dynamic or rolling adhesion of flowing microparticles on a channel wall holds potential to accomplish particle sorting or to selectively transfer reactive species or signals between the wall and flowing particles. Inspired by cell rolling under the direction of adhesion molecules called selectins, we present an engineered platform in which the rolling of flowing microparticles is sustained through the incorporation of entirely synthetic, discrete, nanoscale, attractive features into the nonadhesive (electrostatically repulsive) surface of a flow channel. Focusing on one example or type of nanoscale feature and probing the impact of broad systematic variations in surface feature loading and processing parameters, this study demonstrates how relatively flat, weakly adhesive nanoscale features, positioned with average spacings on the order of tens of nanometers, can produce sustained microparticle rolling. We further demonstrate how the rolling velocity and travel distance depend on flow and surface design. We identify classes of related surfaces that fail to support rolling and present a state space that identifies combinations of surface and processing variables corresponding to transitions between rolling, free particle motion, and arrest. Finally we identify combinations of parameters (surface length scales, particle size, flow rates) where particles can be manipulated with size-selectivity.

Roll-to-Roll Nanoforming of Metals Using Laser-Induced Superplasticity.

PubMed

Goswami, Debkalpa; Munera, Juan C; Pal, Aniket; Sadri, Behnam; Scarpetti, Caio Lui P G; Martinez, Ramses V

2018-05-24

This Letter describes a low-cost, scalable nanomanufacturing process that enables the continuous forming of thin metallic layers with nanoscale accuracy using roll-to-roll, laser-induced superplasticity (R2RLIS). R2RLIS uses a laser shock to induce the ultrahigh-strain-rate deformation of metallic films at room temperature into low-cost polymeric nanomolds, independently of the original grain size of the metal. This simple and inexpensive nanoforming method does not require access to cleanrooms and associated facilities, and can be easily implemented on conventional CO 2 lasers, enabling laser systems commonly used for rapid prototyping or industrial cutting and engraving to fabricate uniform and three-dimensional crystalline metallic nanostructures over large areas. Tuning the laser power during the R2RLIS process enables the control of the aspect ratio and the mechanical and optical properties of the fabricated nanostructures. This roll-to-roll technique successfully fabricates mechanically strengthened gold plasmonic nanostructures with aspect ratios as high as 5 that exhibit high oxidation resistance and strong optical field enhancements. The CO 2 laser used in R2RLIS can also integrate the fabricated nanostructures on transparent flexible substrates with robust interfacial contact. The ability to fabricate ultrasmooth metallic nanostructures using roll-to-roll manufacturing enables the large scale production, at a relatively low-cost, of flexible plasmonic devices toward emerging applications.

Self-rolling up micro 3D structures using temperature-responsive hydrogel sheet

NASA Astrophysics Data System (ADS)

Iwata, Y.; Miyashita, S.; Iwase, E.

2017-12-01

This paper proposes a micro self-folding using a self-rolling up deformation. In the fabrication method at micro scale, self-folding is an especially useful method of easily fabricating complex three-dimensional (3D) structures from engineered two-dimensional (2D) sheets. However, most self-folded structures are limited to 3D structures with a hollow region. Therefore, we made 3D structures with a small hollow region by self-rolling up a 2D sheet consisting of SU-8 and a temperature-responsive hybrid hydrogel of poly(N-isopropylacrylamide-co-acrylic acid) (pNIPAM-AAc). The temperature-responsive hydrogel can provide repetitive deformation, which is a good feature for micro soft robots or actuators, using hydrogel shrinking and swelling. Our micro self-rolling up method is a self-folding method for a 3D structure performed by rolling up a 2D flat sheet, like making a croissant, through continuous self-folding. We used our method to fabricate 3D structures with a small hollow region, such as cylindrical, conical, and croissant-like ellipsoidal structures, and 3D structures with a hollow region, such as spiral shapes. All the structures showed repetitive deformation, forward rolling up in 20 °C cold water and backward rolling up in 40 °C hot water. The results demonstrate that self-rolling up deformation can be useful in the field of micro soft devices.

Lead Pipe Scale Analysis Using Broad-Beam Argon Ion Milling to Elucidate Drinking Water Corrosion

EPA Science Inventory

Herein, we compared the characterization of lead pipe scale removed from a drinking water distribution system using two different cross section methods (conventional polishing and argon ion beam etching). The pipe scale solids were analyzed using scanning electron microscopy (SEM...

NASA five-ball fatigue tester: Over 20 years of research

NASA Technical Reports Server (NTRS)

Zaretsky, E. V.; Parker, R. J.; Anderson, W. J.

1981-01-01

Studies were conducted to determine the effect on rolling-element fatigue life of contact angle, material hardness, chemistry, heat treatment and processing, lubricant type and chemistry, elastohydrodynamic film thickness, deformation and wear, vacuum, and temperature as well as Hertzian and residual stresses. Correlation was established between the results obtained using the five-ball tester and those obtained with full scale rolling-element bearings.

A new solution method for wheel/rail rolling contact.

PubMed

Yang, Jian; Song, Hua; Fu, Lihua; Wang, Meng; Li, Wei

2016-01-01

To solve the problem of wheel/rail rolling contact of nonlinear steady-state curving, a three-dimensional transient finite element (FE) model is developed by the explicit software ANSYS/LS-DYNA. To improve the solving speed and efficiency, an explicit-explicit order solution method is put forward based on analysis of the features of implicit and explicit algorithm. The solution method was first applied to calculate the pre-loading of wheel/rail rolling contact with explicit algorithm, and then the results became the initial conditions in solving the dynamic process of wheel/rail rolling contact with explicit algorithm as well. Simultaneously, the common implicit-explicit order solution method is used to solve the FE model. Results show that the explicit-explicit order solution method has faster operation speed and higher efficiency than the implicit-explicit order solution method while the solution accuracy is almost the same. Hence, the explicit-explicit order solution method is more suitable for the wheel/rail rolling contact model with large scale and high nonlinearity.

Analysis of Ward identities in supersymmetric Yang-Mills theory

NASA Astrophysics Data System (ADS)

Ali, Sajid; Bergner, Georg; Gerber, Henning; Montvay, Istvan; Münster, Gernot; Piemonte, Stefano; Scior, Philipp

2018-05-01

In numerical investigations of supersymmetric Yang-Mills theory on a lattice, the supersymmetric Ward identities are valuable for finding the critical value of the hopping parameter and for examining the size of supersymmetry breaking by the lattice discretisation. In this article we present an improved method for the numerical analysis of supersymmetric Ward identities, which takes into account the correlations between the various observables involved. We present the first complete analysis of supersymmetric Ward identities in N=1 supersymmetric Yang-Mills theory with gauge group SU(3). The results indicate that lattice artefacts scale to zero as O(a^2) towards the continuum limit in agreement with theoretical expectations.

Mobilization of radionuclides from uranium mill tailings and related waste materials in anaerobic environments

USGS Publications Warehouse

Landa, E.R.

2003-01-01

Specific extraction studies in our laboratory have shown that iron and manganese oxide- and alkaline earth sulfate minerals are important hosts of radium in uranium mill tailings. Iron- and sulfate-reducing bacteria may enhance the release of radium (and its analog barium) from uranium mill tailings, oil field pipe scale [a major technologically enhanced naturally occurring radioactive material (TENORM) waste], and jarosite (a common mineral in sulfuric acid processed-tailings). These research findings are reviewed and discussed in the context of nuclear waste forms (such as barium sulfate matrices), radioactive waste management practices, and geochemical environments in the Earth's surficial and shallow subsurface regions.

Enzymatic corn wet milling: engineering process and cost model

PubMed Central

Ramírez, Edna C; Johnston, David B; McAloon, Andrew J; Singh, Vijay

2009-01-01

Background Enzymatic corn wet milling (E-milling) is a process derived from conventional wet milling for the recovery and purification of starch and co-products using proteases to eliminate the need for sulfites and decrease the steeping time. In 2006, the total starch production in USA by conventional wet milling equaled 23 billion kilograms, including modified starches and starches used for sweeteners and ethanol production [1]. Process engineering and cost models for an E-milling process have been developed for a processing plant with a capacity of 2.54 million kg of corn per day (100,000 bu/day). These models are based on the previously published models for a traditional wet milling plant with the same capacity. The E-milling process includes grain cleaning, pretreatment, enzymatic treatment, germ separation and recovery, fiber separation and recovery, gluten separation and recovery and starch separation. Information for the development of the conventional models was obtained from a variety of technical sources including commercial wet milling companies, industry experts and equipment suppliers. Additional information for the present models was obtained from our own experience with the development of the E-milling process and trials in the laboratory and at the pilot plant scale. The models were developed using process and cost simulation software (SuperPro Designer®) and include processing information such as composition and flow rates of the various process streams, descriptions of the various unit operations and detailed breakdowns of the operating and capital cost of the facility. Results Based on the information from the model, we can estimate the cost of production per kilogram of starch using the input prices for corn, enzyme and other wet milling co-products. The work presented here describes the E-milling process and compares the process, the operation and costs with the conventional process. Conclusion The E-milling process was found to be cost competitive with the conventional process during periods of high corn feedstock costs since the enzymatic process enhances the yields of the products in a corn wet milling process. This model is available upon request from the authors for educational, research and non-commercial uses. PMID:19154623

Intense sub-kilometer-scale boundary layer rolls observed in hurricane fran

PubMed

Wurman; Winslow

1998-04-24

High-resolution observations obtained with the Doppler On Wheels (DOW) mobile weather radar near the point of landfall of hurricane Fran (1996) revealed the existence of intense, sub-kilometer-scale, boundary layer rolls that strongly modulated the near-surface wind speed. It is proposed that these structures are one cause of geographically varying surface damage patterns that have been observed after some landfalling hurricanes and that they cause much of the observed gustiness, bringing high-velocity air from aloft to the lowest observable levels. High-resolution DOW radar observations are contrasted with lower-resolution observations obtained with an operational weather radar, which underestimated peak low-level wind speeds.

Non-gaussian signatures of general inflationary trajectories

NASA Astrophysics Data System (ADS)

Horner, Jonathan S.; Contaldi, Carlo R.

2014-09-01

We carry out a numerical calculation of the bispectrum in generalised trajectories of canonical, single-field inflation. The trajectories are generated in the Hamilton-Jacobi (HJ) formalism based on Hubble Slow Roll (HSR) parameters. The calculation allows generally shape and scale dependent bispectra, or dimensionless fNL, in the out-of-slow-roll regime. The distributions of fNL for various shapes and HSR proposals are shown as an example of how this procedure can be used within the context of Monte Carlo exploration of inflationary trajectories. We also show how allowing out-of-slow-roll behaviour can lead to a bispectrum that is relatively large for equilateral shapes.

STS-79 Rolls over from OPF to VAB

NASA Technical Reports Server (NTRS)

1996-01-01

A vantage point high atop the Vehicle Assembly Building (VAB) shrinks the size and scale of the orbiter Atlantis as it is rolled from the Orbiter Processing Facility to the VAB. During the five working days it spends inside the huge building, Atlantis will be mated to the external tank/twin solid rocket booster assembly, and then rolled out to Launch Pad 39A. Here, the SPACEHAB Double Module will be installed in the orbiter's payload bay and final launch preparations will get underway. Atlantis is scheduled for liftoff on Mission STS-79 , the fourth docking with the Russian Space Station Mir, scheduled for July 31.

The new large-scale sweet sorghum industry in the USA

USDA-ARS?s Scientific Manuscript database

Sweet sorghum (Sorghum bicolor) has been widely recognized as a promising sugar feedstock crop for the large-scale manufacture of food-grade and non food-grade bioproducts in the USA. Heckemeyer Mill, located in Sikeston, Missouri, has built and equipped the largest, commercial-scale sweet sorghum ...

Role of intensive milling in the processing of barium ferrite/magnetite/iron hybrid magnetic nano-composites via partial reduction of barium ferrite

DOE Office of Scientific and Technical Information (OSTI.GOV)

Molaei, M.J., E-mail: mj.molaee@merc.ac.ir; Delft Chem Tech, Faculty of Applied Sciences, Delft University of Technology, Julianalaan 136, 2628 BL Delft; Ataie, A.

2015-03-15

In this research a mixture of barium ferrite and graphite was milled for different periods of time and then heat treated at different temperatures. The effects of milling time and heat treatment temperature on the phase composition, thermal behavior, morphology and magnetic properties of the samples have been investigated using X-ray diffraction, differential thermal analysis, high resolution transmission electron microscopy and vibrating sample magnetometer techniques, respectively. X-ray diffraction results revealed that BaFe{sub 12}O{sub 19}/Fe{sub 3}O{sub 4} nanocomposites form after a 20 h milling due to the partial reduction of BaFe{sub 12}O{sub 19}. High resolution transmission electron microscope images of amore » 40 h milled sample showed agglomerated structure consisting of nanoparticles with a mean particle size of 30 nm. Thermal analysis of the samples via differential thermal analysis indicated that for un-milled samples, heat treatment up to 900 °C did not result in α-Fe formation, while for a 20 h milled sample heat treatment at 700 °C resulted in reduction process progress to the formation of α-Fe. Wustite was disappeared in an X-ray diffraction pattern of a heat treated sample at 850 °C, by increasing the milling time from 20 to 40 h. By increasing the milling time, the structure of heat treated samples becomes magnetically softer due to an increase in saturation magnetization and a decrease in coercivity. Saturation magnetization and coercivity of a sample milled for 20 h and heat treated at 850 °C were 126.3 emu/g and 149.5 Oe which by increasing the milling time to 40 h, alter to 169.1 emu/g and 24.3 Oe, respectively. High coercivity values of milled and heat treated samples were attributed to the nano-scale formed iron particles. - Graphical abstract: Display Omitted - Highlights: • Barium ferrite and graphite were treated mechano-thermally. • Increasing milling time increases reduction progress after heat treatment. • Composites including iron nano-crystals forms by milling and heat treatment. • Shorter milling time results in higher H{sub C} of the milled and heat treated samples.« less

Impact Ignition of Low Density Mechanically Activated and Multilayer Foil Ni/Al

NASA Astrophysics Data System (ADS)

Beason, Matthew; Mason, B.; Son, Steven; Groven, Lori

2013-06-01

Mechanical activation (MA) via milling of reactive materials provides a means of lowering the ignition threshold of shock initiated reactions. This treatment provides a finely mixed microstructure with wide variation in the resulting scales of the intraparticle microstructure that makes model validation difficult. In this work we consider nanofoils produced through vapor deposition with well defined periodicity and a similar degree of fine scale mixing. This allows experiments that may be easier to compare with computational models. To achieve this, both equimolar Ni/Al powder that has undergone MA using high energy ball milling and nanofoils milled into a powder using low energy ball milling were used. The Asay Shear impact experiment was conducted on both MA Ni/Al and Ni/Al nanofoil-based powders at low densities (<60%) to examine their impact response and reaction behavior. Scanning electron microscopy and energy-dispersive x-ray spectroscopy were used to verify the microstructure of the materials. The materials' mechanical properties were evaluated using nano-indentation. Onset temperatures were evaluated using differential thermal analysis/differential scanning calorimetry. Impact ignition thresholds, burning rates, temperature field, and ignition delays are reported. Funding from the Defense Threat Reduction Agency (DTRA) Grant Number HDTRA1-10-1-0119. Counter-WMD basic research program, Dr. Suhithi M. Peiris, program director is gratefully acknowledged.

iROLL: does 3-D radioguided occult lesion localization improve surgical management in early-stage breast cancer?

PubMed

Bluemel, Christina; Cramer, Andreas; Grossmann, Christoph; Kajdi, Georg W; Malzahn, Uwe; Lamp, Nora; Langen, Heinz-Jakob; Schmid, Jan; Buck, Andreas K; Grimminger, Hanns-Jörg; Herrmann, Ken

2015-10-01

To prospectively evaluate the feasibility of 3-D radioguided occult lesion localization (iROLL) and to compare iROLL with wire-guided localization (WGL) in patients with early-stage breast cancer undergoing breast-conserving surgery and sentinel lymph node biopsy (SLNB). WGL (standard procedure) and iROLL in combination with SLNB were performed in 31 women (mean age 65.1 ± 11.2 years) with early-stage breast cancer and clinically negative axillae. Patient comfort in respect of both methods was assessed using a ten point scale. SLNB and iROLL were guided by freehand SPECT (fhSPECT). The results of the novel 3-D image-based method were compared with those of WGL, ultrasound-based lesion localization, and histopathology. iROLL successfully detected the malignant primary and at least one sentinel lymph node in 97% of patients. In a single patient (3%), only iROLL, and not WGL, enabled lesion localization. The variability between fhSPECT and ultrasound-based depth localization of breast lesions was low (1.2 ± 1.4 mm). Clear margins were achieved in 81% of the patients; however, precise prediction of clear histopathological surgical margins was not feasible using iROLL. Patients rated iROLL as less painful than WGL with a pain score 0.8 ± 1.2 points (p < 0.01) lower than the score for iROLL. iROLL is a well-tolerated and feasible technique for localizing early-stage breast cancer in the course of breast-conserving surgery, and is a suitable replacement for WGL. As a single image-based procedure for localization of breast lesions and sentinel nodes, iROLL may improve the entire surgical procedure. However, no advantages of the image-guided procedure were found with regard to prediction of complete tumour resection.

Shearlet transform in aliased ground roll attenuation and its comparison with f-k filtering and curvelet transform

NASA Astrophysics Data System (ADS)

Abolfazl Hosseini, Seyed; Javaherian, Abdolrahim; Hassani, Hossien; Torabi, Siyavash; Sadri, Maryam

2015-06-01

Ground roll, which is a Rayleigh surface wave that exists in land seismic data, may mask reflections. Sometimes ground roll is spatially aliased. Attenuation of aliased ground roll is of importance in seismic data processing. Different methods have been developed to attenuate ground roll. The shearlet transform is a directional and multidimensional transform that generates subimages of an input image in different directions and scales. Events with different dips are separated in these subimages. In this study, the shearlet transform is used to attenuate the aliased ground roll. To do this, a shot record is divided into several segments, and the appropriate mute zone is defined for all segments. The shearlet transform is applied to each segment. The subimages related to the non-aliased and aliased ground roll are identified by plotting the energy distributions of subimages with visual checking. Then, muting filters are used on selected subimages. The inverse shearlet transform is applied to the filtered segment. This procedure is repeated for all segments. Finally, all filtered segments are merged using the Hanning window. This method of aliased ground roll attenuation was tested on a synthetic dataset and a field shot record from the west of Iran. The synthetic shot record included strong aliased ground roll, whereas the field shot record did not. To produce the strong aliased ground roll on the field shot record, the data were resampled in the offset direction from 30 to 60 m. To show the performance of the shearlet transform in attenuating the aliased ground roll, we compared the shearlet transform with the f-k filtering and curvelet transform. We showed that the performance of the shearlet transform in the aliased ground roll attenuation is better than that of the f-k filtering and curvelet transform in both the synthetic and field shot records. However, when the dip and frequency content of the aliased ground roll are the same as the reflections, ability of the shearlet transform is limited in attenuating the aliased ground roll.

Some observations on the mechanism of aircraft wing rock

NASA Technical Reports Server (NTRS)

Hwang, C.; Pi, W. S.

1979-01-01

A scale model of the Northrop F-5A was tested in NASA Ames Research Center Eleven-Foot Transonic Tunnel to simulate the wing rock oscillations in a transonic maneuver. For this purpose, a flexible model support device was designed and fabricated, which allowed the model to oscillate in roll at the scaled wing rock frequency. Two tunnel entries were performed to acquire the pressure (steady state and fluctuating) and response data when the model was held fixed and when it was excited by flow to oscillate in roll. Based on these data, a limit cycle mechanism was identified, which supplied energy to the aircraft model and caused the Dutch roll type oscillations, commonly called wing rock. The major origin of the fluctuating pressures that contributed to the limit cycle was traced to the wing surface leading edge stall and the subsequent lift recovery. For typical wing rock oscillations, the energy balance between the pressure work input and the energy consumed by the model's aerodynamic and mechanical damping was formulated and numerical data presented.

Some observations on the mechanism of aircraft wing rock

NASA Technical Reports Server (NTRS)

Hwang, C.; Pi, W. S.

1978-01-01

A pressure scale model of Northrop F-5A was tested in NASA Ames Research Center Eleven-Foot Transonic Tunnel to simulate the wing rock oscillations in a transonic maneuver. For this purpose, a flexible model support device was designed and fabricated which allowed the model to oscillate in roll at the scaled wing rock frequency. Two tunnel entries were performed to acquire the pressure (steady state and fluctuating) and response data when the model was held fixed and when it was excited by flow to oscillate in roll. Based on these data, a limit cycle mechanism was identified which supplied energy to the aircraft model and caused the Dutch roll type oscillations, commonly called wing rock. The major origin of the fluctuating pressures which contributed to the limit cycle was traced to the wing surface leading edge stall and the subsequent lift recovery. For typical wing rock oscillations, the energy balance between the pressure work input and the energy consumed by the model aerodynamic and mechanical damping was formulated and numerical data presented.

EVAPORATOR FLOOR, CLARIFIERS TO THE LEFT, SCALES TO THE RIGHT, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

EVAPORATOR FLOOR, CLARIFIERS TO THE LEFT, SCALES TO THE RIGHT, EVAPORATOR CELLS ONE, TWO AND THREE IN THE BACKGROUND. VIEW FROM NORTHWEST FROM LIME VATS - Lihue Plantation Company, Sugar Mill Building, Haleko Road, Lihue, Kauai County, HI

Study of microforging of metallic nanoflakes in relation to electronic applications

NASA Astrophysics Data System (ADS)

Kang, Wooseung

This dissertation reports the first systematic study of cold microforging; the conversion of micron scale metal powders to thin flakes by a series of plastically deforming impacts in a ball mill at low temperature. The research focused on processing Fe and Cu flakes with submicron thicknesses (nanoflakes) which are expected to find significant applications in electronics. The principal objectives were to develop a detailed understanding of the underlying materials science of the process, and to characterize the material and processing parameters that maximize the rate at which nanoflakes with a specific aspect ratio (diameter/thickness) can be microforged. A model for microforging was developed using Hertzian impact theory to establish the compressive impact energy (Emf) imparted to a spherical powder particle in a ball-powder-ball impact, and the Coffin-Manson relation for cyclical fatigue to determine the number of plastically deforming impacts it could sustain before fracturing. The rate of microforging in the ball mill was obtained from the product of the impact frequency (f) and the statistical probability of impact (p). Both f and p depend on the number of balls and powders, and the collision velocity (v) and the milling vial volume (V). The parameters Emf, p, v and V are specific to the mill and used to develop scaling laws for transferring the process from small vibratory research mills to large commercial equipment. The empirical parameters required by these models were determined by microforging a few grams of powders in small research mills. The validity of the model was assessed by comparing the time required to microforge several hundred grams of a particular powder in a much larger mill, with that determined by scaling the model equations to account for change in mill parameters. The good agreement obtained provided strong support for the microforging model. SEM microphotos and sieving fractions were used to show that the minimum thicknesses, and maximum aspect ratios of the Fe and Cu nanoflakes that could be produced before fracture, are in the ~0.3 μm-0.5 μm range, and agreed well with those calculated from volume conserving sphere-flake transformations. X-ray diffraction measurements showed that the grain sizes of these powders were ~0.1x their thicknesses, and were little changed by microforging. The magnetic hysteresis and permeabilities of the Fe nanoflakes were in good agreement with those computed from the nanoflake geometries. The results indicate that the model of microforging as a statistical random sequence of plastic deformations can be used to develop a commercial process to support the development of their application potential in electronics.

Directional genetic selection by pulp mill effluent on multiple natural populations of three-spined stickleback (Gasterosteus aculeatus).

PubMed

Lind, Emma E; Grahn, Mats

2011-05-01

Contamination can cause a rapid environmental change which may require populations to respond with evolutionary changes. To evaluate the effects of pulp mill effluents on population genetics, we sampled three-spined sticklebacks (Gasterosteus aculeatus) near four pulp mills and four adjacent reference sites and analyzed Amplified Fragment Length Polymorphism (AFLP) to compare genetic variability. A fine scale genetic structure was detected and samples from polluted sites separated from reference sites in multidimensional scaling plots (P<0.005, 1000 permutations) and locus-by-locus Analysis of Molecular Variance (AMOVA) further confirmed that habitats are significantly separated (F(ST)=0.021, P<0.01, 1023 permutations). The amount of genetic variation between populations did not differ between habitats, and populations from both habitats had similar levels of heterozygosity (polluted sites Nei's Hs=0.11, reference sites Nei's Hs=0.11). Still, pairwise F(ST): s between three, out of four, pairs of polluted-reference sites were significant. A F(ST)-outlier analysis showed that 21 (8.4%) loci were statistically different from a neutral distribution at the P<0.05 level and therefore indicated to be under divergent selection. When removing 13 F(ST)-outlier loci, significant at the P<0.01 level, differentiation between habitats disappeared in a multidimensional scaling plot. In conclusion, pulp mill effluence has acted as a selective agent on natural populations of G. aculeatus, causing a convergence in genotype composition change at multiple sites in an open environment. © The Author(s) 2011. This article is published with open access at Springerlink.com

Roll-to-roll fabrication of large scale and regular arrays of three-dimensional nanospikes for high efficiency and flexible photovoltaics

PubMed Central

Leung, Siu-Fung; Gu, Leilei; Zhang, Qianpeng; Tsui, Kwong-Hoi; Shieh, Jia-Min; Shen, Chang-Hong; Hsiao, Tzu-Hsuan; Hsu, Chin-Hung; Lu, Linfeng; Li, Dongdong; Lin, Qingfeng; Fan, Zhiyong

2014-01-01

Three-dimensional (3-D) nanostructures have demonstrated enticing potency to boost performance of photovoltaic devices primarily owning to the improved photon capturing capability. Nevertheless, cost-effective and scalable fabrication of regular 3-D nanostructures with decent robustness and flexibility still remains as a challenging task. Meanwhile, establishing rational design guidelines for 3-D nanostructured solar cells with the balanced electrical and optical performance are of paramount importance and in urgent need. Herein, regular arrays of 3-D nanospikes (NSPs) were fabricated on flexible aluminum foil with a roll-to-roll compatible process. The NSPs have precisely controlled geometry and periodicity which allow systematic investigation on geometry dependent optical and electrical performance of the devices with experiments and modeling. Intriguingly, it has been discovered that the efficiency of an amorphous-Si (a-Si) photovoltaic device fabricated on NSPs can be improved by 43%, as compared to its planar counterpart, in an optimal case. Furthermore, large scale flexible NSP solar cell devices have been fabricated and demonstrated. These results not only have shed light on the design rules of high performance nanostructured solar cells, but also demonstrated a highly practical process to fabricate efficient solar panels with 3-D nanostructures, thus may have immediate impact on thin film photovoltaic industry. PMID:24603964

Roll-to-roll fabrication of large scale and regular arrays of three-dimensional nanospikes for high efficiency and flexible photovoltaics.

PubMed

Leung, Siu-Fung; Gu, Leilei; Zhang, Qianpeng; Tsui, Kwong-Hoi; Shieh, Jia-Min; Shen, Chang-Hong; Hsiao, Tzu-Hsuan; Hsu, Chin-Hung; Lu, Linfeng; Li, Dongdong; Lin, Qingfeng; Fan, Zhiyong

2014-03-07

Three-dimensional (3-D) nanostructures have demonstrated enticing potency to boost performance of photovoltaic devices primarily owning to the improved photon capturing capability. Nevertheless, cost-effective and scalable fabrication of regular 3-D nanostructures with decent robustness and flexibility still remains as a challenging task. Meanwhile, establishing rational design guidelines for 3-D nanostructured solar cells with the balanced electrical and optical performance are of paramount importance and in urgent need. Herein, regular arrays of 3-D nanospikes (NSPs) were fabricated on flexible aluminum foil with a roll-to-roll compatible process. The NSPs have precisely controlled geometry and periodicity which allow systematic investigation on geometry dependent optical and electrical performance of the devices with experiments and modeling. Intriguingly, it has been discovered that the efficiency of an amorphous-Si (a-Si) photovoltaic device fabricated on NSPs can be improved by 43%, as compared to its planar counterpart, in an optimal case. Furthermore, large scale flexible NSP solar cell devices have been fabricated and demonstrated. These results not only have shed light on the design rules of high performance nanostructured solar cells, but also demonstrated a highly practical process to fabricate efficient solar panels with 3-D nanostructures, thus may have immediate impact on thin film photovoltaic industry.

Scaling Flight Tests of Unmanned Air Vehicles

DTIC Science & Technology

2006-09-01

Figure Page Figure 1. Scaled Vehicle used to test Roll over propensity of automobiles . .................. 22 Figure 2. “Davicar...propensity of automobiles . In other research carried out at the University of Delft, Netherlands, the project DAVINCI was developed for

Multi-Scale Stochastic Resonance Spectrogram for fault diagnosis of rolling element bearings

NASA Astrophysics Data System (ADS)

He, Qingbo; Wu, Enhao; Pan, Yuanyuan

2018-04-01

It is not easy to identify incipient defect of a rolling element bearing by analyzing the vibration data because of the disturbance of background noise. The weak and unrecognizable transient fault signal of a mechanical system can be enhanced by the stochastic resonance (SR) technique that utilizes the noise in the system. However, it is challenging for the SR technique to identify sensitive fault information in non-stationary signals. This paper proposes a new method called multi-scale SR spectrogram (MSSRS) for bearing defect diagnosis. The new method considers the non-stationary property of the defective bearing vibration signals, and treats every scale of the time-frequency distribution (TFD) as a modulation system. Then the SR technique is utilized on each modulation system according to each frequencies in the TFD. The SR results are sensitive to the defect information because the energy of transient vibration is distributed in a limited frequency band in the TFD. Collecting the spectra of the SR outputs at all frequency scales then generates the MSSRS. The proposed MSSRS is able to well deal with the non-stationary transient signal, and can highlight the defect-induced frequency component corresponding to the impulse information. Experimental results with practical defective bearing vibration data have shown that the proposed method outperforms the former SR methods and exhibits a good application prospect in rolling element bearing fault diagnosis.

Strengthening behavior of chopped multi-walled carbon nanotube reinforced aluminum matrix composites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shin, S.E.; Bae, D.H., E-mail: donghyun@yonsei.ac.kr

2013-09-15

Strengthening behavior of the aluminum composites reinforced with chopped multi-walled carbon nanotubes (MWCNTs) or aluminum carbide formed during annealing at 500 °C has been investigated. The composites were fabricated by hot-rolling the powders which were ball-milled under various conditions. During the early annealing process, aluminum atoms can cluster inside the tube due to the diffusional flow of aluminum atoms into the tube, providing an increase of the strength of the composite. Further annealing induces the formation of the aluminum carbide phase, leading to an overall drop in the strength of the composites. While the strength of the composites can bemore » evaluated according to the rule of mixture, a particle spacing effect can be additionally imparted on the strength of the composites reinforced with the chopped MWCNTs or the corresponding carbides since the reinforcing agents are smaller than the submicron matrix grains. - Highlights: • Strengthening behavior of chopped CNT reinforced Al-based composites is investigated. • Chopped CNTs have influenced the strength and microstructures of the composites. • Chopped CNTs are created under Ar- 3% H2 atmosphere during mechanical milling. • Strength can be evaluated by the rule of the mixture and a particle spacing effect.« less

Non-Abelian S-term dark energy and inflation

NASA Astrophysics Data System (ADS)

Rodríguez, Yeinzon; Navarro, Andrés A.

2018-03-01

We study the role that a cosmic triad in the generalized SU(2) Proca theory, specifically in one of the pieces of the Lagrangian that involves the symmetric version Sμν of the gauge field strength tensor Fμν, has on dark energy and primordial inflation. Regarding dark energy, the triad behaves asymptotically as a couple of radiation perfect fluids whose energy densities are negative for the S term but positive for the Yang-Mills term. This leads to an interesting dynamical fine-tuning mechanism that gives rise to a combined equation of state parameter ω ≃ - 1 and, therefore, to an eternal period of accelerated isotropic expansion for an ample spectrum of initial conditions. Regarding primordial inflation, one of the critical points of the associated dynamical system can describe a prolonged period of isotropic slow-roll inflation sustained by the S term. This period ends up when the Yang-Mills term dominates the energy density leading to the radiation dominated epoch. Unfortunately, in contrast to the dark energy case, the primordial inflation scenario is strongly sensitive to the coupling constants and initial conditions. The whole model, including the other pieces of the Lagrangian that involve Sμν, might evade the recent strong constraints coming from the gravitational wave signal GW170817 and its electromagnetic counterpart GRB 170817A.

Twin-belt continuous caster with containment and cooling of the exiting cast product for enabling high-speed casting of molten-center product

DOEpatents

Dykes, Charles D.; Daniel, Sabah S.; Wood, J. F. Barry

1990-02-20

In continuously casting molten metal into cast product by a twin-belt machine, it is desirable to achieve dramatic increases in speed (linear feet per minute) at which cast product exits the machine, particularly in installations where steel cast product is intended to feed a downstream regular rolling mill (as distinct from a planetary mill) operating in tandem with the twin-belt caster. Such high-speed casting produces product with a relatively thin shell and molten interior, and the shell tends to bulge outwardly due to metallostatic head pressure of the molten center. A number of cooperative features enable high-speed, twin-belt casting: (1) Each casting belt is slidably supported adjacent to the caster exit pulley for bulge control and enhanced cooling of cast product. (2) Lateral skew steering of each belt provides an effective increase in moving mold length plus a continuity of heat transfer not obtained with prior art belt steering apparatus. (3) The exiting slab is contained and supported downstream from the casting machine to prevent bulging of the shell of the cast product, and (4) spray cooling is incorporated in the exit containment apparatus for secondary cooling of cast product.

Simultaneous Comparison of Two Roller Compaction Techniques and Two Particle Size Analysis Methods.

PubMed

Saarinen, Tuomas; Antikainen, Osmo; Yliruusi, Jouko

2017-11-01

A new dry granulation technique, gas-assisted roller compaction (GARC), was compared with conventional roller compaction (CRC) by manufacturing 34 granulation batches. The process variables studied were roll pressure, roll speed, and sieve size of the conical mill. The main quality attributes measured were granule size and flow characteristics. Within granulations also the real applicability of two particle size analysis techniques, sieve analysis (SA) and fast imaging technique (Flashsizer, FS), was tested. All granules obtained were acceptable. In general, the particle size of GARC granules was slightly larger than that of CRC granules. In addition, the GARC granules had better flowability. For example, the tablet weight variation of GARC granules was close to 2%, indicating good flowing and packing characteristics. The comparison of the two particle size analysis techniques showed that SA was more accurate in determining wide and bimodal size distributions while FS showed narrower and mono-modal distributions. However, both techniques gave good estimates for mean granule sizes. Overall, SA was a time-consuming but accurate technique that provided reliable information for the entire granule size distribution. By contrast, FS oversimplified the shape of the size distribution, but nevertheless yielded acceptable estimates for mean particle size. In general, FS was two to three orders of magnitude faster than SA.

Step scaling and the Yang-Mills gradient flow

NASA Astrophysics Data System (ADS)

Lüscher, Martin

2014-06-01

The use of the Yang-Mills gradient flow in step-scaling studies of lattice QCD is expected to lead to results of unprecedented precision. Step scaling is usually based on the Schrödinger functional, where time ranges over an interval [0 , T] and all fields satisfy Dirichlet boundary conditions at time 0 and T. In these calculations, potentially important sources of systematic errors are boundary lattice effects and the infamous topology-freezing problem. The latter is here shown to be absent if Neumann instead of Dirichlet boundary conditions are imposed on the gauge field at time 0. Moreover, the expectation values of gauge-invariant local fields at positive flow time (and of other well localized observables) that reside in the center of the space-time volume are found to be largely insensitive to the boundary lattice effects.

Effect of Variation of Chord and Span of Ailerons on Rolling and Yawing Moments in Level Flight

NASA Technical Reports Server (NTRS)

Heald, R H; Strother, D H

1929-01-01

This report presents the results of an investigation of the rolling and yawing moments due to ailerons of various chords and spans on two airfoils having the Clark Y and U. S. A. 27 wing sections. Some attention is devoted to a study of the effect of scale on rolling and yawing moments and to the effect of slightly rounding the wing tips. The results apply to level flight with the wing chord set at an angle of attack of +4 degrees and to conditions of zero pitch, zero yaw, and zero roll of the airplane. It is planned later to extend the investigation to other attitudes for monoplane and biplane combinations. The work was conducted in the 10 foot wind tunnel of the Bureau of Standards on models of 60-inch span and 10-inch chord. (author)

Incipient fault feature extraction of rolling bearings based on the MVMD and Teager energy operator.

PubMed

Ma, Jun; Wu, Jiande; Wang, Xiaodong

2018-06-04

Aiming at the problems that the incipient fault of rolling bearings is difficult to recognize and the number of intrinsic mode functions (IMFs) decomposed by variational mode decomposition (VMD) must be set in advance and can not be adaptively selected, taking full advantages of the adaptive segmentation of scale spectrum and Teager energy operator (TEO) demodulation, a new method for early fault feature extraction of rolling bearings based on the modified VMD and Teager energy operator (MVMD-TEO) is proposed. Firstly, the vibration signal of rolling bearings is analyzed by adaptive scale space spectrum segmentation to obtain the spectrum segmentation support boundary, and then the number K of IMFs decomposed by VMD is adaptively determined. Secondly, the original vibration signal is adaptively decomposed into K IMFs, and the effective IMF components are extracted based on the correlation coefficient criterion. Finally, the Teager energy spectrum of the reconstructed signal of the effective IMF components is calculated by the TEO, and then the early fault features of rolling bearings are extracted to realize the fault identification and location. Comparative experiments of the proposed method and the existing fault feature extraction method based on Local Mean Decomposition and Teager energy operator (LMD-TEO) have been implemented using experimental data-sets and a measured data-set. The results of comparative experiments in three application cases show that the presented method can achieve a fairly or slightly better performance than LMD-TEO method, and the validity and feasibility of the proposed method are proved. Copyright © 2018. Published by Elsevier Ltd.

Whole grain for whom and why?

PubMed Central

Frølich, Wenche; Åman, Per

2010-01-01

A definition of whole grain is a critical first step in investigating health claims for whole grain and its products. Today, there is no internationally accepted definition of whole grain. Some existing definitions are broad and commodity-based, including grains with similar end uses, while others are more restricted. Scientific knowledge must be the basis for inclusion of certain grains. It is better to start with a restricted list of grains (a precautionary principle) and extend this as more knowledge becomes available. An exact definition of the raw materials (milled, cracked, crushed, rolled, or flaked) and knowledge of the components providing health effects would appear to be crucial issues for the European authorities when approving health claims. It is important that health claims are evidence-based, sustainable, and officially validated. PMID:20300475

Heat transfer coefficient distribution over the inconel plate cooled from high temperature by the array of water jets

NASA Astrophysics Data System (ADS)

Malinowski, Z.; Telejko, T.; Cebo-Rudnicka, A.; Szajding, A.; Rywotycki, M.; Hadała, B.

2016-09-01

The industrial rolling mills are equipped with systems for controlled water cooling of hot steel products. A cooling rate affects the final mechanical properties of steel which are strongly dependent on microstructure evolution processes. In case of water jets cooling the heat transfer boundary condition can be defined by the heat transfer coefficient. In the present study one and three dimensional heat conduction models have been employed in the inverse solution to heat transfer coefficient. The inconel plate has been heated to about 900oC and then cooled by one, two and six water jets. The plate temperature has been measured by 30 thermocouples. The heat transfer coefficient distributions at plate surface have been determined in time of cooling.

A numerical resolution study of high order essentially non-oscillatory schemes applied to incompressible flow

NASA Technical Reports Server (NTRS)

Weinan, E.; Shu, Chi-Wang

1994-01-01

High order essentially non-oscillatory (ENO) schemes, originally designed for compressible flow and in general for hyperbolic conservation laws, are applied to incompressible Euler and Navier-Stokes equations with periodic boundary conditions. The projection to divergence-free velocity fields is achieved by fourth-order central differences through fast Fourier transforms (FFT) and a mild high-order filtering. The objective of this work is to assess the resolution of ENO schemes for large scale features of the flow when a coarse grid is used and small scale features of the flow, such as shears and roll-ups, are not fully resolved. It is found that high-order ENO schemes remain stable under such situations and quantities related to large scale features, such as the total circulation around the roll-up region, are adequately resolved.

A numerical resolution study of high order essentially non-oscillatory schemes applied to incompressible flow

NASA Technical Reports Server (NTRS)

Weinan, E.; Shu, Chi-Wang

1992-01-01

High order essentially non-oscillatory (ENO) schemes, originally designed for compressible flow and in general for hyperbolic conservation laws, are applied to incompressible Euler and Navier-Stokes equations with periodic boundary conditions. The projection to divergence-free velocity fields is achieved by fourth order central differences through Fast Fourier Transforms (FFT) and a mild high-order filtering. The objective of this work is to assess the resolution of ENO schemes for large scale features of the flow when a coarse grid is used and small scale features of the flow, such as shears and roll-ups, are not fully resolved. It is found that high-order ENO schemes remain stable under such situations and quantities related to large-scale features, such as the total circulation around the roll-up region, are adequately resolved.

The development, design and test of a 66 W/kg (30-W/lb) roll-up solar array

NASA Technical Reports Server (NTRS)

Hasbach, W. A.; Ross, R. G., Jr.

1972-01-01

A program to develop a 250 square foot roll-up solar array with a power-to-weight ratio exceeding 30 watts per pound is described. The system design and fabrication of a full scale engineering development model are discussed. The system and development test program results are presented. Special test equipment and test procedures are included, together with comparisons of experimental and analytical results.

Numerical simulation of small-scale thermal convection in the atmosphere

NASA Technical Reports Server (NTRS)

Somerville, R. C. J.

1973-01-01

A Boussinesq system is integrated numerically in three dimensions and time in a study of nonhydrostatic convection in the atmosphere. Simulation of cloud convection is achieved by the inclusion of parametrized effects of latent heat and small-scale turbulence. The results are compared with the cell structure observed in Rayleigh-Benard laboratory conversion experiments in air. At a Rayleigh number of 4000, the numerical model adequately simulates the experimentally observed evolution, including some prominent transients of a flow from a randomly perturbed initial conductive state into the final state of steady large-amplitude two-dimensional rolls. At Rayleigh number 9000, the model reproduces the experimentally observed unsteady equilibrium of vertically coherent oscillatory waves superimposed on rolls.

Leptogenesis from Left-Handed Neutrino Production during Axion Inflation.

PubMed

Adshead, Peter; Sfakianakis, Evangelos I

2016-03-04

We propose that the observed matter-antimatter asymmetry can be naturally produced as a by-product of axion-driven slow-roll inflation by coupling the axion to standard model neutrinos. We assume that grand unified theory scale right-handed neutrinos are responsible for the masses of the standard model neutrinos and that the Higgs field is light during inflation and develops a Hubble-scale root-mean-square value. In this setup, the rolling axion generates a helicity asymmetry in standard model neutrinos. Following inflation, this helicity asymmetry becomes equal to a net lepton number as the Higgs condensate decays and is partially reprocessed by the SU(2)_{L} sphaleron into a net baryon number.

Effect of Sintering Temperature to Physical, Magnetic Properties and Crystal Structure on Permanent Magnet BaFe12O19 Prepared From Mill Scale

NASA Astrophysics Data System (ADS)

Ramlan; Muljadi; Sardjono, Priyo; Gulo, Fakhili; Setiabudidaya, Dedi

2017-07-01

Permanent magnet of Barium hexa Ferrite with formula BaFe12O19 has been made by metallurgy powder method from raw materials : Barium carbonate (BaCO3 E-merck) and Iron Oxide (Fe2O3 from mill scale). Both of raw materials have been mixed with stoichiometry composition by using a ball mill for 24 hours. The fine powder obtained from milling process was formed by using a hydraulic press at pressure 50 MPa and continued with sintering process. The sintering temperature was varied : 1150°C, 1200°C, 1250°C and 1300°C with holding time for 1 hour. The sintered samples were characterized such as : physical properties (bulk density, porosity and shrinkage), magnetic properties (flux density, remanence, coercivity and magnetic saturation) by using VSM and crystal structure by using XRD. According characterization results show that the crystal structure of BaFe12O19 does not change after sintering process, but the grain size tends to increase. The optimum condition is achieved at temperature 1250°C, and at this condition, the sample has characterization such as : bulk density = 4.35 g/cm3, porosity = 1.03% and firing shrinkage = 11.63%, flux density = 681.1 Gauss, remanence (σr) = 20.78 emu/g, coercivity (Hc) = 2058 Oe and magnetic saturation (σs) 45.16 emu/g.

Enhancing power generation of floating wave power generators by utilization of nonlinear roll-pitch coupling

NASA Astrophysics Data System (ADS)

Yerrapragada, Karthik; Ansari, M. H.; Karami, M. Amin

2017-09-01

We propose utilization of the nonlinear coupling between the roll and pitch motions of wave energy harvesting vessels to increase their power generation by orders of magnitude. Unlike linear vessels that exhibit unidirectional motion, our vessel undergoes both pitch and roll motions in response to frontal waves. This significantly magnifies the motion of the vessel and thus improves the power production by several orders of magnitude. The ocean waves result in roll and pitch motions of the vessel, which in turn causes rotation of an onboard pendulum. The pendulum is connected to an electric generator to produce power. The coupled electro-mechanical system is modeled using energy methods. This paper investigates the power generation of the vessel when the ratio between pitch and roll natural frequencies is about 2 to 1. In that case, a nonlinear energy transfer occurs between the roll and pitch motions, causing the vessel to perform coupled pitch and roll motion even though it is only excited in the pitch direction. It is shown that co-existence of pitch and roll motions significantly enhances the pendulum rotation and power generation. A method for tuning the natural frequencies of the vessel is proposed to make the energy generator robust to variations of the frequency of the incident waves. It is shown that the proposed method enhances the power output of the floating wave power generators by multiple orders of magnitude. A small-scale prototype is developed for the proof of concept. The nonlinear energy transfer and the full rotation of the pendulum in the prototype are observed in the experimental tests.

Multiscale structural changes of atomic order in severely deformed industrial aluminum

NASA Astrophysics Data System (ADS)

Samoilenko, Z. A.; Ivakhnenko, N. N.; Pushenko, E. I.; Pashinskaya, E. G.; Varyukhin, V. N.

2016-02-01

The regularities of multiscale structural changes in the atomic order of the aluminum alloy AD-1 after a severe cold plastic deformation by conventional rolling in smooth rolls or in rolls with relief recesses favorable for shear deformation have been investigated. It has been found that there are four types of structural fractions that differ in scale and perfection of atomic order: crystallographic planes with a long-range order; nanoscale fragments of the planes ( D = 100-300 Å) with an incipient long-range order; smaller groups of atoms ( D = 20-30 Å) of amorphized structure; and the least ordered structural fraction of intercluster medium, keeping only a short-range atomic order (2-3 interatomic distances, 10 Å). The presence of diffuse halo bands in the region of intense Debye lines indicates phase transitions of the order → disorder type with the formation of one to three groups of amorphous clusters with the dominance, in the nanometer scale, of the atomic order characteristic of the family of planes (111), (220), and (311) of crystalline aluminum. We have found a dynamic phase transition with the changing crystallographic order of aluminum, with the matrix structure of a face-centered cubic (FCC) lattice, in the form of nanosized local groups of atoms, that is, the deformation clusters of aluminum with a simple cubic K6 lattice. In the case of conventional rolling, the development of large clusters 50-500 Å in size is observed; however, in the use of rolls with relief recesses, the difference in the sizes of the clusters is one half as much: 50-250 Å. Based on the analysis of the integrated intensity of incoherent X-ray scattering by the samples, we have elucidated the nature of the lowest measured density for the sample subjected to conventional rolling, which consists in the volume concentration of disorderly arranged atoms, the highest of the compared structures, which indicates the formation therein of the greatest amount of fluctuation "voids."

Infection levels of the eyeworm Oxyspirura petrowi and caecal worm Aulonocephalus pennula in the northern bobwhite and scaled quail from the Rolling Plains of Texas.

PubMed

Dunham, N R; Peper, S T; Downing, C; Brake, E; Rollins, D; Kendall, R J

2017-09-01

Northern bobwhite (Colinus virginianus) and scaled quail (Callipepla squamata) have experienced chronic declines within the Rolling Plains ecoregion of Texas. Parasitic infection, which has long been dismissed as a problem in quail, has not been studied thoroughly until recently. A total of 219 northern bobwhite and 101 scaled quail from Mitchell County, Texas were captured and donated from 2014 to 2015, and examined for eyeworm (Oxyspirura petrowi) and caecal worm (Aulonocephalus pennula) infections. In 2014, bobwhites averaged 19.6 ± 1.8 eyeworms and 98.6 ± 8.2 caecal worms, and 23.5 ± 2.1 eyeworms and 129.9 ± 10.7 caecal worms in 2015. Scaled quail averaged 4.8 ± 1.0 eyeworms and 50 ± 6.8 caecal worms in 2014, and 5.7 ± 1.3 eyeworms and 38.1 ± 7.1 caecal worms in 2015. This study expands the knowledge of parasitic infection in quail inhabiting the Rolling Plains of Texas. A significant difference was documented in O. petrowi infection between species but there was no significant difference in A. pennula between quail species. No significant difference was detected in parasite infection between the sexes of both northern bobwhite and scaled quail. This study also documented the highest reported O. petrowi infection in both species of quail. Additional research is needed on the life history and infection dynamics of O. petrowi and A. pennula infections to determine if there are individual- and/or population-level implications due to parasitic infection.

On the formation and stability of nanometer scale precipitates in ferritic alloys during processing and high temperature service

NASA Astrophysics Data System (ADS)

Alinger, Matthew J.

Iron powders containing ≈14wt%Cr and smaller amounts of W and Ti were mechanically alloyed (MA) by ball milling with Y2O3 and subsequently either hot consolidated by hot extrusion or isostatic pressing, or powder annealed, producing very high densities of nm-scale coherent transition phase precipitates, or Y-Ti-O nano-clusters (NCs), along with fine-scale grains. These so-called nanostructured ferritic alloys (NFAs) manifest very high strength (static and creep) and corrosion-oxidation resistance up to temperatures in excess of 800°C. We used a carefully designed matrix of model MA powders and consolidated alloys to systematically assess the NC evolutions during each processing step, and to explore the combined effects of alloy composition and a number of processing variables, including the milling energy, consolidation method and the time and temperature of annealing of the as-milled powders. The stability of the NCs was also characterized during high-temperate post-consolidation annealing of a commercial NFA, MA957. The micro-nanostructural evolutions, and their effects on the alloy strength, were characterized by a combination of techniques, including XRD, TEM, atom-probe tomography (APT) and positron annihilation spectroscopy (PAS). However, small angle neutron scattering (SANS) was the primary tool used to characterize the nm-scale precipitates. The effect of the micro-nanostructure on the alloy strength was assessed by microhardness measurements. The studies revealed the critical sequence-of-events in forming the NCs, involves dissolution of Y, Ti and O during ball milling. The supersaturated solutes then precipitate during hot consolidation or powder annealing. The precipitate volume fraction increases with both the milling energy and Ti additions at lower consolidation and annealing temperatures (850°C), and at higher processing temperatures (1150°C) both are needed to produce NCs. The non-equilibrium kinetics of NC formation are nucleation controlled and independent of time with an effective activation energy of ≈60 kJ/mole. High temperature precipitate coarsening and transformations to oxide phases show a high effective activation energy (≈880 kJ/mole) and have a time dependence characteristic of a dislocation pipe diffusion mechanism. The NCs act as weak to moderately strong (alpha = 0.1 to 0.5) obstacles that can be sheared by dislocations, where the obstacle strength increases with alpha ≈0.37log(r/2b).

VIEW OF SHEAR (ELECTRIC POWERED), SCALE HOUSE TO LEFT. BARS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF SHEAR (ELECTRIC POWERED), SCALE HOUSE TO LEFT. BARS ARE PLACED ON WEIGHING SCALE SHOWN LOWER LEFT. 15-TON CLEVELAND CRANE HANDLES BARS FOR FINAL LOADING INTO RAILROAD CARS (12" BAY) AND FOR MOVING FROM TABLE TO SHEAR TABLE. - Cambria Iron Company, Gautier Works, 12" Mill, Clinton Street & Little Conemaugh River, Johnstown, Cambria County, PA

Single Layer Broadband Anti-Reflective Coatings for Plastic Substrates Produced by Full Wafer and Roll-to-Roll Step-and-Flash Nano-Imprint Lithography

PubMed Central

Burghoorn, Marieke; Roosen-Melsen, Dorrit; de Riet, Joris; Sabik, Sami; Vroon, Zeger; Yakimets, Iryna; Buskens, Pascal

2013-01-01

Anti-reflective coatings (ARCs) are used to lower the reflection of light on the surface of a substrate. Here, we demonstrate that the two main drawbacks of moth eye-structured ARCs—i.e., the lack of suitable coating materials and a process for large area, high volume applications—can be largely eliminated, paving the way for cost-efficient and large-scale production of durable moth eye-structured ARCs on polymer substrates. We prepared moth eye coatings on polymethylmethacrylate (PMMA) and polycarbonate using wafer-by-wafer step-and-flash nano-imprint lithography (NIL). The reduction in reflection in the visible field achieved with these coatings was 3.5% and 4.0%, respectively. The adhesion of the coating to both substrates was good. The moth eye coating on PMMA demonstrated good performance in three prototypical accelerated ageing tests. The pencil hardness of the moth eye coatings on both substrates was <4B, which is less than required for most applications and needs further optimization. Additionally, we developed a roll-to-roll UV NIL pilot scale process and produced moth eye coatings on polyethylene terephthalate (PET) at line speeds up to two meters per minute. The resulting coatings showed a good replication of the moth eye structures and, consequently, a lowering in reflection of the coated PET of 3.0%. PMID:28788301

Developing a "Semi-Systematic" Approach to Using Large-Scale Data-Sets for Small-Scale Interventions: The "Baby Matterz" Initiative as a Case Study

ERIC Educational Resources Information Center

O'Brien, Mark

2011-01-01

The appropriateness of using statistical data to inform the design of any given service development or initiative often depends upon judgements regarding scale. Large-scale data sets, perhaps national in scope, whilst potentially important in informing the design, implementation and roll-out of experimental initiatives, will often remain unused…

Microstructural and Material Quality Effects on Rolling Contact Fatigue of Highly Elastic Intermetallic Ball Bearings

NASA Technical Reports Server (NTRS)

DellaCorte, Christopher; Howard, S. Adam; Thomas, Fransua; Stanford, Malcolm K.

2016-01-01

Rolling element bearings made from highly-elastic intermetallic materials (HIM)s, such as 60NiTi, are under development for applications that require superior corrosion and shock resistance. Compared to steel, intermetallics have been shown to have much lower rolling contact fatigue (RCF) stress capability in simplified 3-ball on rod (ASTM STP 771) fatigue tests. In the 3-ball tests, poor material quality and microstructural flaws negatively affect fatigue life but such relationships have not been established for full-scale 60NiTi bearings. In this paper, 3-ball-on-rod fatigue behavior of two quality grades of 60NiTi are compared to the fatigue life of full-scale 50mm bore ball bearings made from the same materials. 60NiTi RCF rods with material or microstructural flaws suffered from infant mortality failures at all tested stress levels while high quality 60NiTi rods exhibited no failures at lower stress levels. Similarly, tests of full-scale bearings made from flawed materials exhibited early surface fatigue and through crack type failures while bearings made from high quality material did not fail even in long-term tests. Though the full-scale bearing test data is yet preliminary, the results suggest that the simplified RCF test is a good qualitative predictor of bearing performance. These results provide guidance for materials development and to establish minimum quality levels required for successful bearing operation and life.

Microstructural and Material Quality Effects on Rolling Contact Fatigue of Highly Elastic Intermetallic NiTi Ball Bearings

NASA Technical Reports Server (NTRS)

Dellacorte, Christopher; Howard, S. Adam; Thomas, Fransua; Stanford, Malcolm K.

2017-01-01

Rolling element bearings made from highly-elastic intermetallic materials (HIM)s, such as 60NiTi, are under development for applications that require superior corrosion and shock resistance. Compared to steel, intermetallics have been shown to have much lower rolling contact fatigue (RCF) stress capability in simplified 3-ball on rod (ASTM STP 771) fatigue tests. In the 3-ball tests, poor material quality and microstructural flaws negatively affect fatigue life but such relationships have not been established for full-scale 60NiTi bearings. In this paper, 3-ball-on-rod fatigue behavior of two quality grades of 60NiTi are compared to the fatigue life of full-scale 50mm bore ball bearings made from the same materials. 60NiTi RCF rods with material or microstructural flaws suffered from infant mortality failures at all tested stress levels while high quality 60NiTi rods exhibited no failures at lower stress levels. Similarly, tests of full-scale bearings made from flawed materials exhibited early surface fatigue and through crack type failures while bearings made from high quality material did not fail even in long-term tests. Though the full-scale bearing test data is yet preliminary, the results suggest that the simplified RCF test is a good qualitative predictor of bearing performance. These results provide guidance for materials development and to establish minimum quality levels required for successful bearing operation and life.

Scalable alignment of CdS nanowires based on efficient roll-on transfer technique.

PubMed

Yan, Shancheng; Shi, Yi; Xiao, Zhongdang; Wang, Junzhuan; Hu, Dong; Xul, Xin; Lu, Tao; Liu, Aili; Gao, Fan

2013-06-01

A roll-on transfer strategy is developed to enable large-scale and uniform assembly of CdS nanowires on various rigid and flexible substrate materials. In this method, the CdS nanowires were synthesized by the hydrothermal method. The dispersed CdS NWs could be firstly aligned and selectively deposited at the micro/nanochannels between aligned nanofibers on the surface of the donor roller as a result of evaporation-induced flow and capillary action, and then the directional and aligned transfer of the CdS NWs from the donor roller to a receiver substrate via roll-on transfer technique. Finally, a device structures consisting of the nanowire channel and two metal electrodes was fabricated. The electrical property of this device was observed.

Curvature perturbations in the early universe: Theoretical models and observational tests

NASA Astrophysics Data System (ADS)

Vallinotto, Alberto

A very general prediction of inflation is that the power spectrum of density perturbations is characterized by a spectral index ns which is scale independent and approximately equal to unity. Drawing from the potential reconstruction method and adopting the slow-roll parameter expansion technique, we derive all possible single field inflationary potentials that would lead to a scale invariant density spectral index, consistent with current observations. In the process, a new method to determine the functional form of the inflationary potential in the slow roll approximation is devised, based on the reparametrization of the field dynamics with respect to the slow roll parameter epsilon which also allowed to show that under the assumptions made the investigation proved to be exhaustive and that no other solutions are available. Next, we focus on the fact that there exist a large class of inflationary models currently ruled out because the predicted production of curvature perturbations during the slow-roll stage results exponentially suppressed. We investigate whether an alternative mechanism for the generation of curvature perturbations can be devised for such a class of models. In the process, it is shown that it is sufficient for the inflationary potential to exhibit a broken symmetry to successfully convert isocurvature perturbations, which are excited during the slow-roll stage, into curvature perturbations thanks to an inhomogeneous decay stage. This conclusion is general, requiring as a sufficient condition only the fact that the inflation potential is characterized by a broken symmetry. Finally, we show that the perturbations thus produced are generally characterized by a non-negligible degree of non-gaussianity, which then provides a clear experimental signature for experimental detection or rejection.

Up-scaling perovskite solar cell manufacturing from sheet-to-sheet to roll-to-roll: challenges and solutions

NASA Astrophysics Data System (ADS)

Di Giacomo, Francesco; Galagan, Yulia; Shanmugam, Santhosh; Gorter, Harrie; van den Bruele, Fieke; Kirchner, Gerwin; de Vries, Ike; Fledderus, Henri; Lifka, Herbert; Veenstra, Sjoerd; Aernouts, Tom; Groen, Pim; Andrissen, Ronn

2017-08-01

Organometallic halide perovskite solar cells (PSCs) are extremely promising novel materials for thin-film photovoltaics, exhibiting efficiencies over 22% on glass and over 17% on foil 1, 2 . First, a sheet-to-sheet (S2S) production of PSCs and modules on 152x152 mm2 substrates was established, using a combination of sputtering, e-beam evaporation, slot die coating and thermal evaporation (average PCE of 14.6 +/- 1.3 % over 64 devices, more than 10% initial PCE on modules). Later the steps towards a roll-to-roll production will be investigated, starting from the optimization of the stack to make it compatible with a faster production at low temperature. A water based SnOx nanoparticles dispersion was used as solution processable ETL, and the deposition process was scaled-up from spin coating to R2R slot die coating on a 300 mm wide roll of PET/ITO. R2R production is often carried out in ambient atmosphere and involve the use of large volumes of materials, thus a first point is the development of a green solvent and precursor system for the perovskite layer to prevent the emission of toxic compound in the environment. The first results on device fabrication are encouraging, which allow partial R2R manufacturing of flexible PSC (R2R coating of SnOx and perovskite, S2S for Spiro-OMeTAD and gold) with stabilized PCE of 12.6%, a remarkable value for these novel devices. This result can be considered an important milestone towards the production of efficient, low cost, lightweight, flexible PSC on large area.

Current Challenges and Prospective Research for Upscaling Hybrid Perovskite Photovoltaics

DOE PAGES

Williams, Spencer T.; Rajagopal, Adharsh; Chueh, Chu-Chen; ...

2016-02-11

Organic-inorganic hybrid perovskite photovoltaics (PSCs) are poised to push toward technology translation, but significant challenges complicating commercialization remain. Though J-V hysteresis and ecotoxicity are uniquely imposing issues at scale, CH 3NH 3PbI 3 degradation is by far the sharpest limitation to the technology’s potential market contribution. Herein, we offer a perspective on the practical market potential of PSCs, the nature of fundamental PSC challenges at scale, and an outline of prospective solutions for achieving module scale PSC production tailored to intrinsic advantages of CH 3NH 3PbI 3. Although integrating PSCs into the energy grid is complicated by CH 3NH 3PbImore » 3 degradation, the ability of PSCs to contribute to consumer electronics and other niche markets like those organic photovoltaics have sought footing in rests primarily upon the technology’s price point. Thus, slot die, roll-to-roll processing has the greatest potential to enable PSC scale-up, and herein, we present a perspective on the research necessary to realize fully printable PSCs at scale.« less

Effect of Milling Time on the Blocking Temperature of Nanoparticles of Magnetocaloric Gd5Si4

NASA Astrophysics Data System (ADS)

Hadimani, Ravi; Gupta, Shalbh; Harstad, Shane; Pecharsky, Vitalij; Jiles, David; David C Jiles Team; Vitalij Pecharsky Collaboration

Extensive research has been done on giant magnetocaloric material Gd5(SixGe1-x)4 to improve adiabatic temperature/isothermal entropy change. However, there have been only a few reports on fabrication of nanostructure/nanoparticles that can be used to tune various properties by changing the length scale. Recently we have reported fabrication of room temperature ferromagnetic nanoparticles of Gd5Si4 using high energy ball milling. These nanoparticles have potential applications in biomedical engineering such as better T2 MRI contrast agents and in hypothermia. Here we report the effect of milling time on the blocking temperature, micro-structure, crystal structure, and magnetic properties of these nanoparticles. Magnetization vs. temperature at an applied field of 100 Oe is measured for all the ball milled samples. Bulk Gd5Si4 has a transition temperature of ~340 K. There are two phase transitions observed in the nanoparticles, one near 300 K corresponding to the Gd5Si4 phase and another between 75-150 K corresponding to Gd5Si3. Zero Field Cooling (ZFC) and Field Cooling (FC) were measured. The blocking temperatures for the nanoparticles increase with decrease in milling time.

Interpretation of F106B and CV580 in-flight lightning data and form factor determination

NASA Technical Reports Server (NTRS)

Rudolph, T.; Horembala, J.; Eriksen, F. J.; Weigel, H. S.; Elliott, J. R.; Parker, S. L.; Perala, R. A.

1989-01-01

Two topics of in-flight aircraft/lightning interaction are addressed. The first is the analysis of measured data from the NASA F106B Thunderstorm Research Aircraft and the CV580 research program run by the FAA and Wright-Patterson Air Force Base. The CV580 data was investigated in a mostly qualitative sense, while the F106B data was subjected to both statistical and quantitative analysis using linear triggered lightning finite difference models. The second main topic is the analysis of field mill data and the calibration of the field mill systems. The calibration of the F106B field mill system was investigated using an improved finite difference model of the aircraft having a spatial resolution of one-quarter meter. The calibration was applied to measured field mill data acquired during the 1985 thunderstorm season. The experimental determination of form factors useful for field mill calibration was also investigated both experimentally and analytically. The experimental effort involved the use of conducting scale models and an electrolytic tank. An analytic technique was developed to aid in the understanding of the experimental results.

Effects of grinding processes on enzymatic degradation of wheat straw.

PubMed

Silva, Gabriela Ghizzi D; Couturier, Marie; Berrin, Jean-Guy; Buléon, Alain; Rouau, Xavier

2012-01-01

The effectiveness of wheat straw fine to ultra-fine grindings at pilot scale was studied. The produced powders were characterised by their particle-size distribution (laser diffraction), crystallinity (WAXS) and enzymatic degradability (Trichoderma reesei enzymatic cocktail). A large range of wheat-straw powders was produced: from coarse (median particle size ∼800 μm) to fine particles (∼50 μm) using sieve-based grindings, then ultra-fine particles ∼20 μm by jet milling and ∼10 μm by ball milling. The wheat straw degradability was enhanced by the decrease of particle size until a limit: ∼100 μm, up to 36% total carbohydrate and 40% glucose hydrolysis yields. Ball milling samples overcame this limit up to 46% total carbohydrate and 72% glucose yields as a consequence of cellulose crystallinity reduction (from 22% to 13%). Ball milling appeared to be an effective pretreatment with similar glucose yield and superior carbohydrate yield compared to steam explosion pretreatment. Copyright © 2011 Elsevier Ltd. All rights reserved.

Improving Energy Efficiency Via Optimized Charge Motion and Slurry Flow in Plant Scale Sag Mills

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raj K. Rajamani

2006-07-21

A research team from the University of Utah is working to make inroads into saving energy in these SAG mills. In 2003, Industries of the Future Program of the Department of Energy tasked the University of Utah team to build a partnership between the University and the mining industry for the specific purpose of reducing energy consumption in SAG mills. A partnership was formed with Cortez Gold Mines, Outokumpu Technology, Kennecott Utah Copper Corporation, and Process Engineering Resources Inc. At Cortez Gold Operations the shell and pulp lifters of the semiautogenous grinding mill was redesigned. The redesigned shell lifter hasmore » been in operation for over three years and the redesigned pulp lifter has been in operation for over nine months now. This report summarizes the dramatic reductions in energy consumption. Even though the energy reductions are very large, it is safe to say that a 20% minimum reduction would be achieved in any future installations of this technology.« less

Energy efficient bead milling of microalgae: Effect of bead size on disintegration and release of proteins and carbohydrates.

PubMed

Postma, P R; Suarez-Garcia, E; Safi, C; Yonathan, K; Olivieri, G; Barbosa, M J; Wijffels, R H; Eppink, M H M

2017-01-01

The disintegration of three industry relevant algae (Chlorella vulgaris, Neochloris oleoabundans and Tetraselmis suecica) was studied in a lab scale bead mill at different bead sizes (0.3-1mm). Cell disintegration, proteins and carbohydrates released into the water phase followed a first order kinetics. The process is selective towards proteins over carbohydrates during early stages of milling. In general, smaller beads led to higher kinetic rates, with a minimum specific energy consumption of ⩽0.47kWhkg DW -1 for 0.3mm beads. After analysis of the stress parameters (stress number and stress intensity), it appears that optimal disintegration and energy usage for all strains occurs in the 0.3-0.4mm range. During the course of bead milling, the native structure of the marker protein Rubisco was retained, confirming the mildness of the disruption process. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Mesophilic co-digestion of palm oil mill effluent and empty fruit bunches.

PubMed

Kim, Sang-Hyoun; Choi, Seon-Mi; Ju, Hyun-Jun; Jung, Jin-Young

2013-01-01

The palm oil mill industry generates palm oil mill effluent (POME) and empty fruit bunches (EFB) as by-products. This study reports the mesophilic co-digestion of POME with EFB. The biochemical methane potential (BMP) of POME and EFB was 0.397 L CH4/g volatile solids (VS) and 0.264 L CH4/g VS, respectively. In a series of batch tests at various EFB to POME ratios, the maximum methane production rate was achieved at an EFB:POME ratio of 0.25-0.31:1. Performance data from lab-scale digesters confirmed the positive synergism by the addition of EFB to POME, which was attributed to the balanced chemical composition, for example the chemical oxygen demand (COD) to total Kjeldahl nitrogen (TKN) ratio. The EFB addition enhanced the acceptable organic loading rate, methane production, COD removal, and microbial activity. The mesophilic co-digestion of POME and EFB promises to be a viable recycling method to alleviate pollution problems and recover renewable energy in the palm oil mill industry.

Commercialization of biopulping: an energy-saving and environmentally-friendly technology for the paper industry

Treesearch

Ross Swaney; Masood Akhtar; Eric Horn; Michael Lentz; Carl Houtman; John Klungness

2003-01-01

The biopulping process for treating wood chips prior to mechanical pulping has been scaled up through an extensive development program and has been demonstrated at 50 ton semicommercial scale. Detailed engineering analyses and design studies have been performed for full production-scale mill implementation, and the technology is ready for commercial use. This paper...

Introducing close-range photogrammetry for characterizing forest understory plant diversity and surface fuel structure at fine scales

Treesearch

Benjamin C. Bright; E. Louise Loudermilk; Scott M. Pokswinski; Andrew T. Hudak; Joseph J. O' Brien

2016-01-01

Methods characterizing fine-scale fuels and plant diversity can advance understanding of plant-fire interactions across scales and help in efforts to monitor important ecosystems such as longleaf pine (Pinus palustris Mill.) forests of the southeastern United States. Here, we evaluate the utility of close-range photogrammetry for measuring fuels and plant...

How nonperturbative is the infrared regime of Landau gauge Yang-Mills correlators?

NASA Astrophysics Data System (ADS)

Reinosa, U.; Serreau, J.; Tissier, M.; Wschebor, N.

2017-07-01

We study the Landau gauge correlators of Yang-Mills fields for infrared Euclidean momenta in the context of a massive extension of the Faddeev-Popov Lagrangian which, we argue, underlies a variety of continuum approaches. Standard (perturbative) renormalization group techniques with a specific, infrared-safe renormalization scheme produce so-called decoupling and scaling solutions for the ghost and gluon propagators, which correspond to nontrivial infrared fixed points. The decoupling fixed point is infrared stable and weakly coupled, while the scaling fixed point is unstable and generically strongly coupled except for low dimensions d →2 . Under the assumption that such a scaling fixed point exists beyond one-loop order, we find that the corresponding ghost and gluon scaling exponents are, respectively, 2 αF=2 -d and 2 αG=d at all orders of perturbation theory in the present renormalization scheme. We discuss the relation between the ghost wave function renormalization, the gluon screening mass, the scale of spectral positivity violation, and the gluon mass parameter. We also show that this scaling solution does not realize the standard Becchi-Rouet-Stora-Tyutin symmetry of the Faddeev-Popov Lagrangian. Finally, we discuss our findings in relation to the results of nonperturbative continuum methods.

Tachyon constant-roll inflation

NASA Astrophysics Data System (ADS)

Mohammadi, A.; Saaidi, Kh.; Golanbari, T.

2018-04-01

The constant-roll inflation is studied where the inflaton is taken as a tachyon field. Based on this approach, the second slow-roll parameter is taken as a constant which leads to a differential equation for the Hubble parameter. Finding an exact solution for the Hubble parameter is difficult and leads us to a numerical solution for the Hubble parameter. On the other hand, since in this formalism the slow-roll parameter η is constant and could not be assumed to be necessarily small, the perturbation parameters should be reconsidered again which, in turn, results in new terms appearing in the amplitude of scalar perturbations and the scalar spectral index. Utilizing the numerical solution for the Hubble parameter, we estimate the perturbation parameter at the horizon exit time and compare it with observational data. The results show that, for specific values of the constant parameter η , we could have an almost scale-invariant amplitude of scalar perturbations. Finally, the attractor behavior for the solution of the model is presented, and we determine that the feature could be properly satisfied.

Evidence of a rolling motion of a microparticle on a silicon wafer in a liquid environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schiwek, Simon; Stark, Robert W., E-mail: stark@csi.tu-darmstadt.de, E-mail: dietz@csi.tu-darmstadt.de; Dietz, Christian, E-mail: stark@csi.tu-darmstadt.de, E-mail: dietz@csi.tu-darmstadt.de

2016-05-21

The interaction of micro- and nanometer-sized particles with surfaces plays a crucial role when small-scale structures are built in a bottom-up approach or structured surfaces are cleaned in the semiconductor industry. For a reliable quantification of the interaction between individual particles and a specific surface, however, the motion type of the particle must be known. We developed an approach to unambiguously distinguish between sliding and rolling particles. To this end, fluorescent particles were partially bleached in a confocal laser scanning microscope to tailor an optical inhomogeneity, which allowed for the identification of the characteristic motion pattern. For the manipulation, themore » water flow generated by a fast moving cantilever-tip of an atomic force microscope enabled the contactless pushing of the particle. We thus experimentally evidenced a rolling motion of a micrometer-sized particle directly with a fluorescence microscope. A similar approach could help to discriminate between rolling and sliding particles in liquid flows of microfluidic systems.« less

Roll-to-Roll Laser-Printed Graphene-Graphitic Carbon Electrodes for High-Performance Supercapacitors.

PubMed

Kang, Sangmin; Lim, Kyungmi; Park, Hyeokjun; Park, Jong Bo; Park, Seong Chae; Cho, Sung-Pyo; Kang, Kisuk; Hong, Byung Hee

2018-01-10

Carbon electrodes including graphene and thin graphite films have been utilized for various energy and sensor applications, where the patterning of electrodes is essentially included. Laser scribing in a DVD writer and inkjet printing were used to pattern the graphene-like materials, but the size and speed of fabrication has been limited for practical applications. In this work, we devise a simple strategy to use conventional laser-printer toner materials as precursors for graphitic carbon electrodes. The toner was laser-printed on metal foils, followed by thermal annealing in hydrogen environment, finally resulting in the patterned thin graphitic carbon or graphene electrodes for supercapacitors. The electrochemical cells made of the graphene-graphitic carbon electrodes show remarkably higher energy and power performance compared to conventional supercapacitors. Furthermore, considering the simplicity and scalability of roll-to-roll (R2R) electrode patterning processes, the proposed method would enable cheaper and larger-scale synthesis and patterning of graphene-graphitic carbon electrodes for various energy applications in the future.

Flies compensate for unilateral wing damage through modular adjustments of wing and body kinematics

PubMed Central

Iwasaki, Nicole A.; Elzinga, Michael J.; Melis, Johan M.; Dickinson, Michael H.

2017-01-01

Using high-speed videography, we investigated how fruit flies compensate for unilateral wing damage, in which loss of area on one wing compromises both weight support and roll torque equilibrium. Our results show that flies control for unilateral damage by rolling their body towards the damaged wing and by adjusting the kinematics of both the intact and damaged wings. To compensate for the reduction in vertical lift force due to damage, flies elevate wingbeat frequency. Because this rise in frequency increases the flapping velocity of both wings, it has the undesired consequence of further increasing roll torque. To compensate for this effect, flies increase the stroke amplitude and advance the timing of pronation and supination of the damaged wing, while making the opposite adjustments on the intact wing. The resulting increase in force on the damaged wing and decrease in force on the intact wing function to maintain zero net roll torque. However, the bilaterally asymmetrical pattern of wing motion generates a finite lateral force, which flies balance by maintaining a constant body roll angle. Based on these results and additional experiments using a dynamically scaled robotic fly, we propose a simple bioinspired control algorithm for asymmetric wing damage. PMID:28163885

Flies compensate for unilateral wing damage through modular adjustments of wing and body kinematics.

PubMed

Muijres, Florian T; Iwasaki, Nicole A; Elzinga, Michael J; Melis, Johan M; Dickinson, Michael H

2017-02-06

Using high-speed videography, we investigated how fruit flies compensate for unilateral wing damage, in which loss of area on one wing compromises both weight support and roll torque equilibrium. Our results show that flies control for unilateral damage by rolling their body towards the damaged wing and by adjusting the kinematics of both the intact and damaged wings. To compensate for the reduction in vertical lift force due to damage, flies elevate wingbeat frequency. Because this rise in frequency increases the flapping velocity of both wings, it has the undesired consequence of further increasing roll torque. To compensate for this effect, flies increase the stroke amplitude and advance the timing of pronation and supination of the damaged wing, while making the opposite adjustments on the intact wing. The resulting increase in force on the damaged wing and decrease in force on the intact wing function to maintain zero net roll torque. However, the bilaterally asymmetrical pattern of wing motion generates a finite lateral force, which flies balance by maintaining a constant body roll angle. Based on these results and additional experiments using a dynamically scaled robotic fly, we propose a simple bioinspired control algorithm for asymmetric wing damage.

Collision-based energetic comparison of rolling and hopping over obstacles

PubMed Central

Iida, Fumiya

2018-01-01

Locomotion of machines and robots operating in rough terrain is strongly influenced by the mechanics of the ground-machine interactions. A rolling wheel in terrain with obstacles is subject to collisional energy losses, which is governed by mechanics comparable to hopping or walking locomotion. Here we investigate the energetic cost associated with overcoming an obstacle for rolling and hopping locomotion, using a simple mechanics model. The model considers collision-based interactions with the ground and the obstacle, without frictional losses, and we quantify, analyse, and compare the sources of energetic costs for three locomotion strategies. Our results show that the energetic advantages of the locomotion strategies are uniquely defined given the moment of inertia and the Froude number associated with the system. We find that hopping outperforms rolling at larger Froude numbers and vice versa. The analysis is further extended for a comparative study with animals. By applying size and inertial properties through an allometric scaling law of hopping and trotting animals to our models, we found that the conditions at which hopping becomes energetically advantageous to rolling roughly corresponds to animals’ preferred gait transition speeds. The energetic collision losses as predicted by the model are largely verified experimentally. PMID:29538459

Aluminum-based one- and two-dimensional micro fin array structures: high-throughput fabrication and heat transfer testing

NASA Astrophysics Data System (ADS)

Primeaux, Philip A.; Zhang, Bin; Zhang, Xiaoman; Miller, Jacob; Meng, W. J.; KC, Pratik; Moore, Arden L.

2017-02-01

Microscale fin array structures were replicated onto surfaces of aluminum 1100 and aluminum 6061 alloy (Al1100/Al6061) sheet metals through room-temperature instrumented roll molding. Aluminum-based micro fin arrays were replicated at room temperature, and the fabrication process is one with high throughput and low cost. One-dimensional (1D) micro fin arrays were made through one-pass rolling, while two-dimensional (2D) micro fin arrays were made by sequential 90° cross rolling with the same roller sleeve. For roll molding of 1D micro fins, fin heights greater than 600 µm were achieved and were shown to be proportional to the normal load force per feature width. At a given normal load force, the fin height was further shown to scale inversely with the hardness of the sheet metal. For sequential 90° cross rolling, morphologies of roll molded 2D micro fin arrays were examined, which provided clues to understand how plastic deformation occurred under cross rolling conditions. A series of pool boiling experiments on low profile Al micro fin array structures were performed within Novec 7100, a widely used commercial dielectric coolant. Results for both horizontal and vertical surface orientations show that roll molded Al micro fin arrays can increase heat flux at fixed surface temperature as compared to un-patterned Al sheet. The present results further suggest that many factors beyond just increased surface area can influence heat transfer performance, including surface finish and the important multiphase transport mechanisms in and around the fin geometry. These factors must also be considered when designing and optimizing micro fin array structures for heat transfer applications.

Transient rolling friction model for discrete element simulations of sphere assemblies

NASA Astrophysics Data System (ADS)

Kuhn, Matthew R.

2014-03-01

The rolling resistance between a pair of contacting particles can be modeled with two mechanisms. The first mechanism, already widely addressed in the DEM literature, involves a contact moment between the particles. The second mechanism involves a reduction of the tangential contact force, but without a contact moment. This type of rotational resistance, termed creep-friction, is the subject of the paper. Within the creep-friction literature, the term “creep” does not mean a viscous mechanism, but rather connotes a slight slip that accompanies rolling. Two extremes of particle motions bound the range of creep-friction behaviors: a pure tangential translation is modeled as a Cattaneo-Mindlin interaction, whereas prolonged steady-state rolling corresponds to the traditional wheel-rail problem described by Carter, Poritsky, and others. DEM simulations, however, are dominated by the transient creep-friction rolling conditions that lie between these two extremes. A simplified model is proposed for the three-dimensional transient creep-friction rolling of two spheres. The model is an extension of the work of Dahlberg and Alfredsson, who studied the two-dimensional interactions of disks. The proposed model is applied to two different systems: a pair of spheres and a large dense assembly of spheres. Although creep-friction can reduce the tangential contact force that would otherwise be predicted with Cattaneo-Mindlin theory, a significant force reduction occurs only when the rate of rolling is much greater than the rate of translational sliding and only after a sustained period of rolling. When applied to the deviatoric loading of an assembly of spheres, the proposed creep-friction model has minimal effect on macroscopic strength or stiffness. At the micro-scale of individual contacts, creep-friction does have a modest influence on the incremental contact behavior, although the aggregate effect on the assembly's behavior is minimal.

Indomethacin nanocrystals prepared by different laboratory scale methods: effect on crystalline form and dissolution behavior

NASA Astrophysics Data System (ADS)

Martena, Valentina; Censi, Roberta; Hoti, Ela; Malaj, Ledjan; Di Martino, Piera

2012-12-01

The objective of this study is to select very simple and well-known laboratory scale methods able to reduce particle size of indomethacin until the nanometric scale. The effect on the crystalline form and the dissolution behavior of the different samples was deliberately evaluated in absence of any surfactants as stabilizers. Nanocrystals of indomethacin (native crystals are in the γ form) (IDM) were obtained by three laboratory scale methods: A (Batch A: crystallization by solvent evaporation in a nano-spray dryer), B (Batch B-15 and B-30: wet milling and lyophilization), and C (Batch C-20-N and C-40-N: Cryo-milling in the presence of liquid nitrogen). Nanocrystals obtained by the method A (Batch A) crystallized into a mixture of α and γ polymorphic forms. IDM obtained by the two other methods remained in the γ form and a different attitude to the crystallinity decrease were observed, with a more considerable decrease in crystalline degree for IDM milled for 40 min in the presence of liquid nitrogen. The intrinsic dissolution rate (IDR) revealed a higher dissolution rate for Batches A and C-40-N, due to the higher IDR of α form than γ form for the Batch A, and the lower crystallinity degree for both the Batches A and C-40-N. These factors, as well as the decrease in particle size, influenced the IDM dissolution rate from the particle samples. Modifications in the solid physical state that may occur using different particle size reduction treatments have to be taken into consideration during the scale up and industrial development of new solid dosage forms.

Hardness and swelling behaviour of epoxidized natural rubber/recycled acrylonitrile-butadiene rubber (ENR 50/NBRr) blends

NASA Astrophysics Data System (ADS)

Ahmad, Hazwani Syaza; Ismail, Hanafi; Rashid, Azura A.

2017-07-01

This recent work is to investigate the hardness and swelling behaviour of epoxidized natural rubber/recycled acrylonitrile-butadiene rubber (ENR 50/NBRr) blends. ENR 50/NBRr blends were prepared by two-roll mills with five different loading of NBRr from 5 to 35 phr. Results indicated that the hardness of ENR 50/NBRr blends increased as recycled NBR increased due to the improvement in crosslink density of the blends. Increasing NBRr content gives ENR 50/NBRr blends better resistance towards swelling. Higher degree of crosslinking will increase the swelling resistance and reduce the penetration of toluene into the blends. The presence of polar group in ENR 50 and NBRr give better hardness properties and swelling behaviour of the ENR 50/NBRr blends compared to the NR/NBRr blends.

Spray forming -- Aluminum: Third annual report (Phase 2). Technical progress -- Summary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kozarek, R.L.

1998-04-20

Commercial production of aluminum sheet and plate by spray atomization and deposition is a potentially attractive manufacturing alternative to conventional ingot metallurgy/hot-milling and to continuous casting processes because of reduced energy requirements and reduced cost. To realize the full potential of the technology, the Aluminum Company of America (Alcoa), under contract by the US Department of Energy, is investigating currently available state-of-the-art atomization devices to develop nozzle design concepts whose spray characteristics are tailored for continuous sheet production. This third technical progress report will summarize research and development work conducted during the period 1997 October through 1998 March. Included aremore » the latest optimization work on the Alcoa III nozzle, results of spray forming runs with 6111 aluminum alloy and preliminary rolling trials of 6111 deposits.« less

How decoherence affects the probability of slow-roll eternal inflation

NASA Astrophysics Data System (ADS)

Boddy, Kimberly K.; Carroll, Sean M.; Pollack, Jason

2017-07-01

Slow-roll inflation can become eternal if the quantum variance of the inflaton field around its slowly rolling classical trajectory is converted into a distribution of classical spacetimes inflating at different rates, and if the variance is large enough compared to the rate of classical rolling that the probability of an increased rate of expansion is sufficiently high. Both of these criteria depend sensitively on whether and how perturbation modes of the inflaton interact and decohere. Decoherence is inevitable as a result of gravitationally sourced interactions whose strength are proportional to the slow-roll parameters. However, the weakness of these interactions means that decoherence is typically delayed until several Hubble times after modes grow beyond the Hubble scale. We present perturbative evidence that decoherence of long-wavelength inflaton modes indeed leads to an ensemble of classical spacetimes with differing cosmological evolutions. We introduce the notion of per-branch observables—expectation values with respect to the different decohered branches of the wave function—and show that the evolution of modes on individual branches varies from branch to branch. Thus, single-field slow-roll inflation fulfills the quantum-mechanical criteria required for the validity of the standard picture of eternal inflation. For a given potential, the delayed decoherence can lead to slight quantitative adjustments to the regime in which the inflaton undergoes eternal inflation.

Modifications of Graphite and Multiwall Carbon Nanotubes in the Presence of Urea

NASA Astrophysics Data System (ADS)

Duraia, El-Shazly M.; Fahami, Abbas; Beall, Gary W.

2018-02-01

The effect of high-energy ball milling on two carbon allotropes, graphite and multiwall carbon nanotubes (MWCNT) in the presence of urea has been studied. Samples were investigated using Raman spectroscopy, x-ray diffraction, scanning electron microscope (SEM) and x-ray photoelectron spectroscopy (XPS). Nitrogen-doped graphene has been successfully synthesized via a simple scalable mechanochemistry method using urea and graphite powder precursors. XPS results revealed the existence of the different nitrogen atoms configurations including pyridine, pyrrodic and graphitic N. SEM observations showed that the graphene nanosheets morphology become more wrinkles folded and crumbled as the milling time increased. The ID/IG ratio also increased as the milling time rose. The presence of both D' and G + D bands at 1621 cm-1 and 2940 cm-1, respectively, demonstrated the nitrogen incorporation in the graphene lattice Two factors contribute to the used urea: first it helps to exfoliate graphite into graphene, and second it preserves the graphitic structure from damage during the milling process as well as acting as a solid-state nitrogen source. Based on the phase analysis, the d-spacing of MWCNT samples in the presence of urea decreased due to the mechanical force in the milling process as the milling time increased. On the other hand, in the graphite case, due to its open flat surface, the graphite (002) peak shifts toward lower two theta as the milling time increase. Such findings are important and could be used for large-scale production of N-doped graphene, diminishing the use of either dangerous chemicals or sophisticated equipment.

Maintenance measures for preservation and recovery of permeable pavement surface infiltration rate--The effects of street sweeping, vacuum cleaning, high pressure washing, and milling.

PubMed

Winston, Ryan J; Al-Rubaei, Ahmed M; Blecken, Godecke T; Viklander, Maria; Hunt, William F

2016-03-15

The surface infiltration rates (SIR) of permeable pavements decline with time as sediment and debris clog pore spaces. Effective maintenance techniques are needed to ensure the hydraulic functionality and water quality benefits of this stormwater control. Eight different small-scale and full-scale maintenance techniques aimed at recovering pavement permeability were evaluated at ten different permeable pavement sites in the USA and Sweden. Maintenance techniques included manual removal of the upper 2 cm of fill material, mechanical street sweeping, regenerative-air street sweeping, vacuum street sweeping, hand-held vacuuming, high pressure washing, and milling of porous asphalt. The removal of the upper 2 cm of clogging material did not significantly improve the SIR of concrete grid paves (CGP) and permeable interlocking concrete pavers (PICP) due to the inclusion of fines in the joint and bedding stone during construction, suggesting routine maintenance cannot overcome improper construction. For porous asphalt maintenance, industrial hand-held vacuum cleaning, pressure washing, and milling were increasingly successful at recovering the SIR. Milling to a depth of 2.5 cm nearly restored the SIR for a 21-year old porous asphalt pavement to like-new conditions. For PICP, street sweepers employing suction were shown to be preferable to mechanical sweepers; additionally, maintenance efforts may become more intensive over time to maintain a threshold SIR, as maintenance was not 100% effective at removing clogging material. Copyright © 2015 Elsevier Ltd. All rights reserved.

Microstructure Evolution During Creep of Cold Worked Austenitic Stainless Steel

NASA Astrophysics Data System (ADS)

Krishan Yadav, Hari; Ballal, A. R.; Thawre, M. M.; Vijayanand, V. D.

2018-04-01

The 14Cr–15Ni austenitic stainless steel (SS) with additions of Ti, Si, and P has been developed for their superior creep strength and better resistance to void swelling during service as nuclear fuel clad and wrapper material. Cold working induces defects such as dislocations that interact with point defects generated by neutron irradiation and facilitates recombination to make the material more resistant to void swelling. In present investigation, creep properties of the SS in mill annealed condition (CW0) and 40 % cold worked (CW4) condition were studied. D9I stainless steel was solution treated at 1333 K for 30 minutes followed by cold rolling. Uniaxial creep tests were performed at 973 K for various stress levels ranging from 175-225 MPa. CW4 samples exhibited better creep resistance as compared to CW0 samples. During creep exposure, cold worked material exhibited phenomena of recovery and recrystallization wherein new strain free grains were observed with lesser dislocation network. In contrast CW0 samples showed no signs of recovery and recrystallization after creep exposure. Partial recrystallization on creep exposure led to higher drop in hardness in cold worked sample as compared to that in mill annealed sample. Accelerated precipitation of carbides at the grain boundaries was observed during creep exposure and this phenomenon was more pronounced in cold worked sample.

Uncovering the true nature of deformation microstructures using 3D analysis methods

NASA Astrophysics Data System (ADS)

Ferry, M.; Quadir, M. Z.; Afrin, N.; Xu, W.; Loeb, A.; Soe, B.; McMahon, C.; George, C.; Bassman, L.

2015-08-01

Three-dimensional electron backscatter diffraction (3D EBSD) has emerged as a powerful technique for generating 3D crystallographic information in reasonably large volumes of a microstructure. The technique uses a focused ion beam (FIB) as a high precision serial sectioning device for generating consecutive ion milled surfaces of a material, with each milled surface subsequently mapped by EBSD. The successive EBSD maps are combined using a suitable post-processing method to generate a crystallographic volume of the microstructure. The first part of this paper shows the usefulness of 3D EBSD for understanding the origin of various structural features associated with the plastic deformation of metals. The second part describes a new method for automatically identifying the various types of low and high angle boundaries found in deformed and annealed metals, particularly those associated with grains exhibiting subtle and gradual variations in orientation. We have adapted a 2D image segmentation technique, fast multiscale clustering, to 3D EBSD data using a novel variance function to accommodate quaternion data. This adaptation is capable of segmenting based on subtle and gradual variation as well as on sharp boundaries within the data. We demonstrate the excellent capabilities of this technique with application to 3D EBSD data sets generated from a range of cold rolled and annealed metals described in the paper.

Impact of functionalized particle structure on roll compaction/dry granulation and tableting of calcium carbonate.

PubMed

Grote, Simon; Kleinebudde, Peter

2018-06-10

The influence of a functionalized raw material particle structure on the granulation behavior and tabletabilty of calcium carbonate (CaCO 3 ) was investigated. Therefore, a milled grade of CaCO 3 was compared to different binary mixtures of milled and functionalized CaCO 3 . Relevant properties of raw materials, ribbons and granules were measured. The starting materials and two fractions of dry granules were compressed to tablets. The tabletability of granules was compared to that of the powders and the influence of specific compaction force and granule size on tablet tensile strength was evaluated. Adding functionalized particles drastically influenced the granulation and tableting behavior of CaCO 3 . Increasing proportions increased the ribbon porosity and granule size. Tensile strength of tablets from powder mixtures and granules was increased as well. Nevertheless, adding functionalized CaCO 3 led to a loss in tabletability induced by a previous compaction step to an extent depending on its proportion in the formulation. A clear influence of the particle morphology on granulation and tableting behavior was demonstrated by the study. The functionalized structure showed aspects of a more plastic deformation behavior. Adding functionalized CaCO 3 to a mixture, even in small amounts, seemed to be beneficial to increase granule size and tablet strength. Copyright © 2018 Elsevier B.V. All rights reserved.

Bound on largest r ∼< 0.1 from sub-Planckian excursions of inflaton

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chatterjee, Arindam; Mazumdar, Anupam, E-mail: arindam@hri.res.in, E-mail: a.mazumdar@lancaster.ac.uk

2015-01-01

In this paper we will discuss the range of large tensor to scalar ratio, r, obtainable from a sub-Planckian excursion of a single, slow roll driven inflaton field. In order to obtain a large r for such a scenario one has to depart from a monotonic evolution of the slow roll parameters in such a way that one still satisfies all the current constraints of \\texttt(Planck), such as the scalar amplitude, the tilt in the scalar power spectrum, running and running of the tilt close to the pivot scale. Since the slow roll parameters evolve non-monotonically, we will also considermore » the evolution of the power spectrum on the smallest scales, i.e. at P{sub s}(k ∼ 10{sup 16} Mpc{sup −1})∼< 10{sup −2}, to make sure that the amplitude does not become too large. All these constraints tend to keep the tensor to scalar ratio, r ∼< 0.1. We scan three different kinds of potential for supersymmetric flat directions and obtain the benchmark points which satisfy all the constraints. We also show that it is possible to go beyond r ∼> 0.1 provided we relax the upper bound on the power spectrum on the smallest scales.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, Daqiang, E-mail: dq80jiang@126.com; Cui, Lishan; Jiang, Jiang

Graphical abstract: - Highlights: • In situ NiTi/Nb(Ti) composites were fabricated. • The transformation temperature was affected by the mixing Ti:Ni atomic ratios. • The NiTi component became micron-scale lamella after forging and rolling. • The composite exhibited high strength and high damping capacity. - Abstract: This paper reports on the creation of a series of in situ NiTi/Nb(Ti) composites with controllable transformation temperatures based on the pseudo-binary hypereutectic transformation of NiTi–Nb system. The composite constituent morphology was controlled by forging and rolling. It is found that the thickness of the NiTi lamella in the composite reached micron level aftermore » the hot-forging and cold-rolling. The NiTi/Nb(Ti) composite exhibited high damping capacity as well as high yield strength.« less

Preliminary flight-test results of an advanced technology light twin-engine airplane /ATLIT/

NASA Technical Reports Server (NTRS)

Holmes, B. J.; Kohlman, D. L.; Crane, H. L.

1976-01-01

The present status and flight-test results are presented for the ATLIT airplane. The ATLIT is a Piper PA-34 Seneca I modified by the installation of new wings incorporating the GA(W)-1 (Whitcomb) airfoil, reduced wing area, roll-control spoilers, and full-span Fowler flaps. Flight-test results on stall and spoiler roll characteristics show good agreement with wind-tunnel data. Maximum power-off lift coefficients are greater than 3.0 with flaps deflected 37 deg. With flaps down, spoiler deflections can produce roll helix angles in excess of 0.11 rad. Flight testing is planned to document climb and cruise performance, and supercritical propeller performance and noise characteristics. The airplane is scheduled for testing in the NASA-Langley Research Center Full-Scale Tunnel.

Convection patterns in a liquid metal under an imposed horizontal magnetic field.

PubMed

Yanagisawa, Takatoshi; Hamano, Yozo; Miyagoshi, Takehiro; Yamagishi, Yasuko; Tasaka, Yuji; Takeda, Yasushi

2013-12-01

We performed laboratory experiments of Rayleigh-Bénard convection with liquid gallium under various intensities of a uniform imposed horizontal magnetic field. An ultrasonic velocity profiling method was used to visualize the spatiotemporal structure of the flows with simultaneous monitoring of the temperature fluctuations in the liquid gallium layer. The explored Rayleigh numbers Ra range from the critical value for onset of convection to 10(5); the Chandrasekhar number Q covers values up to 1100. A regime diagram of the convection patterns was established in relation to the Ra and Q values for a square vessel with aspect ratio 5. We identified five flow regimes: (I) a fluctuating large-scale pattern without rolls, (II) weakly constrained rolls with fluctuations, (III) a continuous oscillation of rolls, (IV) repeated roll number transitions with random reversals of the flow direction, and (V) steady two-dimensional (2D) rolls. These flow regimes are classified by the Ra/Q values, the ratio of the buoyancy to the Lorentz force. Power spectra from the temperature time series indicate that regimes I and II have the features of developed turbulence, while the other regimes do not. The region of steady 2D rolls (Busse balloon) extends to high Ra values in the present setting by a horizontal magnetic field and regime V is located inside the Busse balloon. Concerning the instabilities of the steady 2D rolls, regime III is the traveling wave convection developed from the oscillatory instability. Regime IV can be regarded as a state of phase turbulence, which is induced by intermittent occurrences of the skewed-varicose instability.

Experimental Investigation of Minimum Quantity Lubrication in Meso-scale Milling with Varying Tool Diameter

NASA Astrophysics Data System (ADS)

Yusof, M. Q. M.; Harun, H. N. S. B.; Bahar, R.

2018-01-01

Minimum quantity lubrication (MQL) is a method that uses a very small amount of liquid to reduce friction between cutting tool and work piece during machining. The implementation of MQL machining has become a viable alternative to flood cooling machining and dry machining. The overall performance has been evaluated during meso-scale milling of mild steel using different diameter milling cutters. Experiments have been conducted under two different lubrication condition: dry and MQL with variable cutting parameters. The tool wear and its surface roughness, machined surfaces microstructure and surface roughness were observed for both conditions. It was found from the results that MQL produced better results compared to dry machining. The 0.5 mm tool has been selected as the most optimum tool diameter to be used with the lowest surface roughness as well as the least flank wear generation. For the workpiece, it was observed that the cutting temperature possesses crucial effect on the microstructure and the surface roughness of the machined surface and bigger diameter tool actually resulted in higher surface roughness. The poor conductivity of the cutting tool may be one of reasons behind.

Dual-Doppler lidar observation of horizontal convective rolls and near-surface streaks

NASA Astrophysics Data System (ADS)

Iwai, Hironori; Ishii, Shoken; Tsunematsu, Nobumitsu; Mizutani, Kohei; Murayama, Yasuhiro; Itabe, Toshikazu; Yamada, Izumi; Matayoshi, Naoki; Matsushima, Dai; Weiming, Sha; Yamazaki, Takeshi; Iwasaki, Toshiki

2008-07-01

Dual-Doppler lidar and heliborne sensors were used to investigate the three-dimensional (3D) structure of the wind field over Sendai Airport in June 2007. The 3D structures of several-hundred-meter-scale horizontal convective rolls (HCRs) in the sea-breeze layer were observed by the dual-Doppler lidar. The scale of the HCRs determined by the heliborne sensors roughly agreed with that determined by the dual-Doppler lidar. Analysis of the dual-Doppler lidar data showed that the region of upward flow in the HCRs originated in near-surface low-speed streaks. This structure is consistent with the results of large-eddy simulations of the atmospheric boundary layer. The aspect ratios of the HCRs were close to those predicted by linear theories.

The Hydrophobicity and Adhesion of Heterogeneous Surfaces of Dual Nanometer and Micron Scale Structures

DTIC Science & Technology

2011-04-11

scale post geometry. superhydrophobic , surface modification, adhesion, contact angle, Cassie, Wenzel, PDMS, CYTOP, Teflon AF, roll-off angle U U U U SAR...width > 1, the micro-scale features dominated the wetting state regardless of the nano-scale post geometry., KEYWORDS superhydrophobic , surface... superhydrophobicity can be routinely found in nature. Fo~ example, many plant leaves1.2, bird feathers3, insect wings and insect legs4 take advantage of

Atomic-scale thermocapillary flow in focused ion beam milling

NASA Astrophysics Data System (ADS)

Das, Kallol; Johnson, Harley; Freund, Jonathan

2016-11-01

Focused ion beams (FIB) offer an attractive tool for nanometer-scale manufacturing and material processing, particularly because they can be focused to a few nanometer diameter spot. This motivates their use for many applications, such as sample preparation for transmission electron microscopy (TEM), forming nanometer scale pores in thin films for DNA sequencing. Despite its widespread use, the specific mechanisms of FIB milling, especially at high ion fluxes for which significant phase change might occur, remains incompletely understood. Here we investigate the process of nanopore fabrication in thin Si films using molecular dynamics simulation where Ga+ ions are used as the focused ions. For a range of ion intensities in a realistic configuration, a recirculating melt region develops, which is seen to flow with a symmetrical pattern, counter to how it would flow were it is driven by the ion momentum flux. Such flow is potentially important for the shape and composition of the formed structures. Relevant stress scales and estimated physical properties of silicon under these extreme conditions support the importance thermocapillary effects. A continuum flow model with Marangoni forcing reproduces the flow.

Replicating Impact of a Primary School HIV Prevention Programme: Primary School Action for Better Health, Kenya

ERIC Educational Resources Information Center

Maticka-Tyndale, E.; Mungwete, R.; Jayeoba, O.

2014-01-01

School-based programmes to combat the spread of HIV have been demonstrated to be effective over the short-term when delivered on a small scale. The question addressed here is whether results obtained with small-scale delivery are replicable in large-scale roll-out. Primary School Action for Better Health (PSABH), a programme to train teachers to…

Stable isotope analyses of the peralkaline volcanics Gregory Rift Valley, Kenya

NASA Technical Reports Server (NTRS)

Black, S.; Macdonald, R.; Fallick, A. E.; Kelly, M.

1993-01-01

Delta O-18 analyses of the Naivasha rhyolites, basalts, Menengai trachytes and the Yatta phonolite are presented together with D/H analyses of the Naivasha rhyolites. Delta O-18 results vary from 5.7 to 8.9 per mill which is within the reported range of delta O-18 analyses for continental volcanics. Closure temperatures calulated from the basalts and rhyolites show equilibration to be at magmatic temperatures. D/H values range from -40 to -148 per mill indicating that the rhyolites have undergone large scale degasssing.

Primordial non-Gaussianity and power asymmetry with quantum gravitational effects in loop quantum cosmology

NASA Astrophysics Data System (ADS)

Zhu, Tao; Wang, Anzhong; Kirsten, Klaus; Cleaver, Gerald; Sheng, Qin

2018-02-01

Loop quantum cosmology provides a resolution of the classical big bang singularity in the deep Planck era. The evolution, prior to the usual slow-roll inflation, naturally generates excited states at the onset of the slow-roll inflation. It is expected that these quantum gravitational effects could leave its fingerprints on the primordial perturbation spectrum and non-Gaussianity, and lead to some observational evidences in the cosmic microwave background. While the impact of the quantum effects on the primordial perturbation spectrum has been already studied and constrained by current data, in this paper we continue to study such effects but now on the non-Gaussianity of the primordial curvature perturbations. We present detailed and analytical calculations of the non-Gaussianity and show explicitly that the corrections due to the quantum effects are at the same magnitude of the slow-roll parameters in the observable scales and thus are well within current observational constraints. Despite this, we show that the non-Gaussianity in the squeezed limit can be enhanced at superhorizon scales and it is these effects that can yield a large statistical anisotropy on the power spectrum through the Erickcek-Kamionkowski-Carroll mechanism.

Three Collaborative Models for Scaling Up Evidence-Based Practices

PubMed Central

Roberts, Rosemarie; Jones, Helen; Marsenich, Lynne; Sosna, Todd; Price, Joseph M.

2015-01-01

The current paper describes three models of research-practice collaboration to scale-up evidence-based practices (EBP): (1) the Rolling Cohort model in England, (2) the Cascading Dissemination model in San Diego County, and (3) the Community Development Team model in 53 California and Ohio counties. Multidimensional Treatment Foster Care (MTFC) and KEEP are the focal evidence-based practices that are designed to improve outcomes for children and families in the child welfare, juvenile justice, and mental health systems. The three scale-up models each originated from collaboration between community partners and researchers with the shared goal of wide-spread implementation and sustainability of MTFC/KEEP. The three models were implemented in a variety of contexts; Rolling Cohort was implemented nationally, Cascading Dissemination was implemented within one county, and Community Development Team was targeted at the state level. The current paper presents an overview of the development of each model, the policy frameworks in which they are embedded, system challenges encountered during scale-up, and lessons learned. Common elements of successful scale-up efforts, barriers to success, factors relating to enduring practice relationships, and future research directions are discussed. PMID:21484449

Roll plane analysis of on-aircraft antennas

NASA Technical Reports Server (NTRS)

Burnside, W. D.; Marhefka, R. J.; Byu, C. L.

1974-01-01

Roll plane radiation patterns of on-aircraft antennas are analyzed using high frequency solutions. Aircraft-antenna pattern performance in which the aircraft is modelled in its most basic form is presented. The fuselage is assumed to be a perfectly conducting elliptic cylinder with the antennas mounted near the top or bottom. The wings are simulated by arbitrarily many sided flat plates and the engines by circular cylinders. The patterns in each case are verified by measured results taken on simple models as well as scale models of actual aircraft.

[Air stripping-UASB process for the treatment of evaporator condensate from a Kraft pulp mill].

PubMed

Zhou, Wei-li; Qin, Xiao-peng; Yu, Jun; Imai, Tsuyoshi; Ukita, Masao

2006-04-01

Evaporator condensate from a kraft pulp mill is characterized by high temperature, high strength, poor nutrition, and some odor and inhibitive materials. In this study, air stripping-UASB process was developed to treat the wastewater from a kraft pulp mill. The lab scale study demonstrated that air stripping process removed 70%-80% of the volatile organic sulfur compounds. After that, the UASB reactor showed high efficiency, at the organic loading rate (COD) of 30 kg x (m3 x d)(-1), COD removal was retained about 95%. On the other hand, the inoculated granules were broken in the new surroundings and were replaced with the newly formed granules The scanning electronic microscope (SEM) observation showed wide difference of the predominant anaerobic microorganisms in the seed and newly formed granules.

Assessment of a New Silicon Carbide Tubular Honeycomb Membrane for Treatment of Olive Mill Wastewaters

PubMed Central

Fraga, Maria C.; Sanches, Sandra; Crespo, João G.; Pereira, Vanessa J.

2017-01-01

Extremely high removals of total suspended solids and oil and grease were obtained when olive mill wastewaters were filtered using new silicon carbide tubular membranes. These new membranes were used at constant permeate flux to treat real olive mill wastewaters at pilot scale. The filtration conditions were evaluated and optimized in terms of the selection of the permeate flux and flux maintenance strategies employed—backpulsing and backwashing—in order to reduce fouling formation. The results obtained reveal that the combination of backpulses and backwashes helps to maintain the permeate flux, avoids transmembrane pressure increase and decreases the cake resistance. Moreover, membrane cleaning procedures were compared and the main agents responsible for fouling formation identified. Results also show that, under total recirculation, despite an increased concentration of pollutants in the feed stream, the quality of the permeate is maintained. Membrane filtration using silicon carbide membranes is an effective alternative to dissolved air flotation and can be applied efficiently to remove total suspended solids and oil and grease from olive mill wastewaters. PMID:28264453

Assessment of a New Silicon Carbide Tubular Honeycomb Membrane for Treatment of Olive Mill Wastewaters.

PubMed

Fraga, Maria C; Sanches, Sandra; Crespo, João G; Pereira, Vanessa J

2017-02-27

Extremely high removals of total suspended solids and oil and grease were obtained when olive mill wastewaters were filtered using new silicon carbide tubular membranes. These new membranes were used at constant permeate flux to treat real olive mill wastewaters at pilot scale. The filtration conditions were evaluated and optimized in terms of the selection of the permeate flux and flux maintenance strategies employed-backpulsing and backwashing-in order to reduce fouling formation. The results obtained reveal that the combination of backpulses and backwashes helps to maintain the permeate flux, avoids transmembrane pressure increase and decreases the cake resistance. Moreover, membrane cleaning procedures were compared and the main agents responsible for fouling formation identified. Results also show that, under total recirculation, despite an increased concentration of pollutants in the feed stream, the quality of the permeate is maintained. Membrane filtration using silicon carbide membranes is an effective alternative to dissolved air flotation and can be applied efficiently to remove total suspended solids and oil and grease from olive mill wastewaters.

Experimental evaluation of tool run-out in micro milling

NASA Astrophysics Data System (ADS)

Attanasio, Aldo; Ceretti, Elisabetta

2018-05-01

This paper deals with micro milling cutting process focusing the attention on tool run-out measurement. In fact, among the effects of the scale reduction from macro to micro (i.e., size effects) tool run-out plays an important role. This research is aimed at developing an easy and reliable method to measure tool run-out in micro milling based on experimental tests and an analytical model. From an Industry 4.0 perspective this measuring strategy can be integrated into an adaptive system for controlling cutting forces, with the objective of improving the production quality, the process stability, reducing at the same time the tool wear and the machining costs. The proposed procedure estimates the tool run-out parameters from the tool diameter, the channel width, and the phase angle between the cutting edges. The cutting edge phase measurement is based on the force signal analysis. The developed procedure has been tested on data coming from micro milling experimental tests performed on a Ti6Al4V sample. The results showed that the developed procedure can be successfully used for tool run-out estimation.

The Effect of Milling Time on the Microstructural Characteristics and Strengthening Mechanisms of NiMo-SiC Alloys Prepared via Powder Metallurgy.

PubMed

Yang, Chao; Muránsky, Ondrej; Zhu, Hanliang; Thorogood, Gordon J; Avdeev, Maxim; Huang, Hefei; Zhou, Xingtai

2017-04-06

A new generation of alloys, which rely on a combination of various strengthening mechanisms, has been developed for application in molten salt nuclear reactors. In the current study, a battery of dispersion and precipitation-strengthened (DPS) NiMo-based alloys containing varying amounts of SiC (0.5-2.5 wt %) were prepared from Ni-Mo-SiC powder mixture via a mechanical alloying (MA) route followed by spark plasma sintering (SPS) and rapid cooling. Neutron Powder Diffraction (NPD), Electron Back Scattering Diffraction (EBSD), and Transmission Electron Microscopy (TEM) were employed in the characterization of the microstructural properties of these in-house prepared NiMo-SiC DPS alloys. The study showed that uniformly-dispersed SiC particles provide dispersion strengthening, the precipitation of nano-scale Ni₃Si particles provides precipitation strengthening, and the solid-solution of Mo in the Ni matrix provides solid-solution strengthening. It was further shown that the milling time has significant effects on the microstructural characteristics of these alloys. Increased milling time seems to limit the grain growth of the NiMo matrix by producing well-dispersed Mo₂C particles during sintering. The amount of grain boundaries greatly increases the Hall-Petch strengthening, resulting in significantly higher strength in the case of 48-h-milled NiMo-SiC DPS alloys compared with the 8-h-milled alloys. However, it was also shown that the total elongation is considerably reduced in the 48-h-milled NiMo-SiC DPS alloy due to high porosity. The porosity is a result of cold welding of the powder mixture during the extended milling process.

The Effect of Milling Time on the Microstructural Characteristics and Strengthening Mechanisms of NiMo-SiC Alloys Prepared via Powder Metallurgy

PubMed Central

Yang, Chao; Muránsky, Ondrej; Zhu, Hanliang; Thorogood, Gordon J.; Avdeev, Maxim; Huang, Hefei; Zhou, Xingtai

2017-01-01

A new generation of alloys, which rely on a combination of various strengthening mechanisms, has been developed for application in molten salt nuclear reactors. In the current study, a battery of dispersion and precipitation-strengthened (DPS) NiMo-based alloys containing varying amounts of SiC (0.5–2.5 wt %) were prepared from Ni-Mo-SiC powder mixture via a mechanical alloying (MA) route followed by spark plasma sintering (SPS) and rapid cooling. Neutron Powder Diffraction (NPD), Electron Back Scattering Diffraction (EBSD), and Transmission Electron Microscopy (TEM) were employed in the characterization of the microstructural properties of these in-house prepared NiMo-SiC DPS alloys. The study showed that uniformly-dispersed SiC particles provide dispersion strengthening, the precipitation of nano-scale Ni3Si particles provides precipitation strengthening, and the solid-solution of Mo in the Ni matrix provides solid-solution strengthening. It was further shown that the milling time has significant effects on the microstructural characteristics of these alloys. Increased milling time seems to limit the grain growth of the NiMo matrix by producing well-dispersed Mo2C particles during sintering. The amount of grain boundaries greatly increases the Hall–Petch strengthening, resulting in significantly higher strength in the case of 48-h-milled NiMo-SiC DPS alloys compared with the 8-h-milled alloys. However, it was also shown that the total elongation is considerably reduced in the 48-h-milled NiMo-SiC DPS alloy due to high porosity. The porosity is a result of cold welding of the powder mixture during the extended milling process. PMID:28772747

Nanomanufacturing : nano-structured materials made layer-by-layer.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cox, James V.; Cheng, Shengfeng; Grest, Gary Stephen

Large-scale, high-throughput production of nano-structured materials (i.e. nanomanufacturing) is a strategic area in manufacturing, with markets projected to exceed $1T by 2015. Nanomanufacturing is still in its infancy; process/product developments are costly and only touch on potential opportunities enabled by growing nanoscience discoveries. The greatest promise for high-volume manufacturing lies in age-old coating and imprinting operations. For materials with tailored nm-scale structure, imprinting/embossing must be achieved at high speeds (roll-to-roll) and/or over large areas (batch operation) with feature sizes less than 100 nm. Dispersion coatings with nanoparticles can also tailor structure through self- or directed-assembly. Layering films structured with thesemore » processes have tremendous potential for efficient manufacturing of microelectronics, photovoltaics and other topical nano-structured devices. This project is designed to perform the requisite R and D to bring Sandia's technology base in computational mechanics to bear on this scale-up problem. Project focus is enforced by addressing a promising imprinting process currently being commercialized.« less

Fault Diagnosis for Rolling Bearings under Variable Conditions Based on Visual Cognition

PubMed Central

Cheng, Yujie; Zhou, Bo; Lu, Chen; Yang, Chao

2017-01-01

Fault diagnosis for rolling bearings has attracted increasing attention in recent years. However, few studies have focused on fault diagnosis for rolling bearings under variable conditions. This paper introduces a fault diagnosis method for rolling bearings under variable conditions based on visual cognition. The proposed method includes the following steps. First, the vibration signal data are transformed into a recurrence plot (RP), which is a two-dimensional image. Then, inspired by the visual invariance characteristic of the human visual system (HVS), we utilize speed up robust feature to extract fault features from the two-dimensional RP and generate a 64-dimensional feature vector, which is invariant to image translation, rotation, scaling variation, etc. Third, based on the manifold perception characteristic of HVS, isometric mapping, a manifold learning method that can reflect the intrinsic manifold embedded in the high-dimensional space, is employed to obtain a low-dimensional feature vector. Finally, a classical classification method, support vector machine, is utilized to realize fault diagnosis. Verification data were collected from Case Western Reserve University Bearing Data Center, and the experimental result indicates that the proposed fault diagnosis method based on visual cognition is highly effective for rolling bearings under variable conditions, thus providing a promising approach from the cognitive computing field. PMID:28772943

A Hybrid Generalized Hidden Markov Model-Based Condition Monitoring Approach for Rolling Bearings

PubMed Central

Liu, Jie; Hu, Youmin; Wu, Bo; Wang, Yan; Xie, Fengyun

2017-01-01

The operating condition of rolling bearings affects productivity and quality in the rotating machine process. Developing an effective rolling bearing condition monitoring approach is critical to accurately identify the operating condition. In this paper, a hybrid generalized hidden Markov model-based condition monitoring approach for rolling bearings is proposed, where interval valued features are used to efficiently recognize and classify machine states in the machine process. In the proposed method, vibration signals are decomposed into multiple modes with variational mode decomposition (VMD). Parameters of the VMD, in the form of generalized intervals, provide a concise representation for aleatory and epistemic uncertainty and improve the robustness of identification. The multi-scale permutation entropy method is applied to extract state features from the decomposed signals in different operating conditions. Traditional principal component analysis is adopted to reduce feature size and computational cost. With the extracted features’ information, the generalized hidden Markov model, based on generalized interval probability, is used to recognize and classify the fault types and fault severity levels. Finally, the experiment results show that the proposed method is effective at recognizing and classifying the fault types and fault severity levels of rolling bearings. This monitoring method is also efficient enough to quantify the two uncertainty components. PMID:28524088

Rolling and aging in temperature-ramp soft adhesion

NASA Astrophysics Data System (ADS)

Boniello, Giuseppe; Tribet, Christophe; Marie, Emmanuelle; Croquette, Vincent; Zanchi, Dražen

2018-01-01

Immediately before adsorption to a horizontal substrate, sinking polymer-coated colloids can undergo a complex sequence of landing, jumping, crawling, and rolling events. Using video tracking, we studied the soft adhesion to a horizontal flat plate of micron-size colloids coated by a controlled molar fraction f of the poly(lysine)-grafted-poly(N-isopropylacrylamide) (PLL-g-PNIPAM) which is a temperature-sensitive polymer. We ramp the temperature from below to above Tc=32 ±1∘C , at which the PNIPAM polymer undergoes a transition, triggering attractive interaction between microparticles and surface. The adsorption rate, the effective in-plane (x -y ) diffusion constant, and the average residence time distribution over z were extracted from the Brownian motion records during last seconds before immobilization. Experimental data are understood within a rate-equations-based model that includes aging effects and includes three populations: the untethered, the rolling, and the arrested colloids. We show that preadsorption dynamics casts a characteristic scaling function α (f ) proportional to the number of available PNIPAM patches met by soft contact during Brownian rolling. In particular, the increase of in-plane diffusivity with increasing f is understood: The stickiest particles have the shortest rolling regime prior to arrest, so that their motion is dominated by the untethered phase.

Roll-to-roll Slot-die Printed Polymer Solar Cell by Self-Assembly.

PubMed

Yang, Junyu; Lin, Yuanbao; Zheng, Wenhao; Liu, Alei; Cai, Wanzhu; Yu, Xiaomin; Zhang, Fengling; Liang, Quanbin; Wu, Hongbin; Qin, Donghuan; Hou, Lintao

2018-06-12

Extremely simplified one-step roll-to-roll slot-die printed flexible ITO-free polymer solar cells (PSCs) are demonstrated based on ternary blends of electron-donor polymer thieno [3,4-b]thiophene/benzodithiophene (PTB7), electron-acceptor fullerene [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) and electron extracting polymer poly [(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) at room temperature (RT) in ambient air. The flexible ITO-free PSC exhibits a comparable power conversion efficiency (PCE) with the device employing complicated two-step slot-die printing (5.29% vs 5.41%), which indicates that PFN molecules can migrate from the ternary nanocomposite towards Ag cathode via vertical self-assembly during the one-step slot-die printing process in air. To confirm the migration of PFN, the morphology and elemental analysis as well as charge transport of different active layers are investigated with in-situ transient film drying process, transmission electron microscopy, atomic force microscopy, contact angle and surface energy, X-ray photoelectron spectroscopy, scanning electron microscope, impedance spectroscopy, transient photovoltage and transient photocurrent as well as laser beam induced current. Moreover, the good air and mechanical stability of the flexible device with a decent PCE achieved in 1 cm2 PSCs at RT in air suggests the feasibility of energy-saving and time-saving one-step slot-die printing to large-scale roll-to-roll manufacture in the future.

Use of Industrial Waste (Al-Dross, Red Mud, Mill Scale) as Fluxing Agents in the Sulfurization of Fe-Ni-Cu-Co Alloy by Carbothermic Reduction of Calcium Sulfate

NASA Astrophysics Data System (ADS)

Heo, Jung Ho; Jeong, Eui Hyuk; Nam, Chul Woo; Park, Kyung Ho; Park, Joo Hyun

2018-06-01

The use of industrial waste [mill scale (MS), red mud (RM), Al-dross (AD)] as fluxing agents in the sulfurization of Fe-Ni-Cu-Co alloy to matte (Fe-Ni-Cu-Co-S) by carbothermic reduction of CaSO4 was investigated at 1673 K (1400 °C). The sulfurization efficiency (SE) was 76 (± 2) pct at RM or AD single fluxing. However, SE drastically increased to approximately 89 pct at a `5AD + 5MS' combination, which was equivalent to reagent-grade chemical `5Al2O3 + 5Fe2O3' fluxing (SE = 88 pct). The present results can be used to improve the cost-effective recovery of rare metals (Ni and Co) from deep sea manganese nodules.

Use of Industrial Waste (Al-Dross, Red Mud, Mill Scale) as Fluxing Agents in the Sulfurization of Fe-Ni-Cu-Co Alloy by Carbothermic Reduction of Calcium Sulfate

NASA Astrophysics Data System (ADS)

Heo, Jung Ho; Jeong, Eui Hyuk; Nam, Chul Woo; Park, Kyung Ho; Park, Joo Hyun

2018-03-01

The use of industrial waste [mill scale (MS), red mud (RM), Al-dross (AD)] as fluxing agents in the sulfurization of Fe-Ni-Cu-Co alloy to matte (Fe-Ni-Cu-Co-S) by carbothermic reduction of CaSO4 was investigated at 1673 K (1400 °C). The sulfurization efficiency (SE) was 76 (± 2) pct at RM or AD single fluxing. However, SE drastically increased to approximately 89 pct at a `5AD + 5MS' combination, which was equivalent to reagent-grade chemical `5Al2O3 + 5Fe2O3' fluxing (SE = 88 pct). The present results can be used to improve the cost-effective recovery of rare metals (Ni and Co) from deep sea manganese nodules.

Unsteady Aerodynamic Modeling in Roll for the NASA Generic Transport Model

NASA Technical Reports Server (NTRS)

Murphy, Patrick C.; Klein, Vladislav; Frink, Neal T.

2012-01-01

Reducing the impact of loss-of-control conditions on commercial transport aircraft is a primary goal of the NASA Aviation Safety Program. One aspect in developing the supporting technologies is to improve the aerodynamic models that represent these adverse conditions. Aerodynamic models appropriate for loss of control conditions require a more general mathematical representation to predict nonlinear unsteady behaviors. In this paper, a more general mathematical model is proposed for the subscale NASA Generic Transport Model (GTM) that covers both low and high angles of attack. Particular attention is devoted to the stall region where full-scale transports have demonstrated a tendency for roll instability. The complete aerodynamic model was estimated from dynamic wind-tunnel data. Advanced computational methods are used to improve understanding and visualize the flow physics within the region where roll instability is a factor.

Performance Modeling and Cost Analysis of a Pilot-Scale Reverse Osmosis Process for the Final Purification of Olive Mill Wastewater

PubMed Central

Ochando-Pulido, Javier Miguel; Hodaifa, Gassan; Victor-Ortega, Maria Dolores; Martinez-Ferez, Antonio

2013-01-01

A secondary treatment for olive mill wastewater coming from factories working with the two-phase olive oil production process (OMW-2) has been set-up on an industrial scale in an olive oil mill in the premises of Jaén (Spain). The secondary treatment comprises Fenton-like oxidation followed by flocculation-sedimentation and filtration through olive stones. In this work, performance modelization and preliminary cost analysis of a final reverse osmosis (RO) process was examined on pilot scale for ulterior purification of OMW-2 with the goal of closing the loop of the industrial production process. Reduction of concentration polarization on the RO membrane equal to 26.3% was provided upon increment of the turbulence over the membrane to values of Reynolds number equal to 2.6 × 104. Medium operating pressure (25 bar) should be chosen to achieve significant steady state permeate flux (21.1 L h−1 m−2) and minimize membrane fouling, ensuring less than 14.7% flux drop and up to 90% feed recovery. Under these conditions, irreversible fouling below 0.08 L h−2 m−2 bar−1 helped increase the longevity of the membrane and reduce the costs of the treatment. For 10 m3 day−1 OMW-2 on average, 47.4 m2 required membrane area and 0.87 € m−3 total costs for the RO process were estimated. PMID:24957058

Low-Cost Opportunity for Small-Scale Manufacture of Hardwood Blanks

Treesearch

Bruce G. Hansen; Philip A. Araman

1985-01-01

We analyzed the manufacture of standard-size hardwood blanks from lumber on a relatively small scale by conventional processing. Requiring an investment of just over $200,000, the conventional mill can process 500 M bf (thousand board feet) of kiln-dried lumber annually. The study focused on the economics associated with manufacture of blanks from four species -...

Managing calcium oxalate scale in the bleach plant

Treesearch

Alan Rudie; Peter Hart

2005-01-01

To comply with the U.S. Environmental Protection Agency's "Cluster Rule," most U.S. mills have switched from the use of chlorine to chlorine dioxide as the oxidant in the first stage of bleaching. This process change has a downside. it increases the formation of mineral scale in bleach plants. Typically, calcium oxalate forms in the chlorine dioxide...

Chapter 7:Mineral Scale Management

Treesearch

Alan W. Rudie; Peter W. Hart

2012-01-01

Mineral scale problems are not new to pulp mills and bleach plants. The liquor recovery system ensures that white liquor is saturated in calcium carbonate, and this mineral will precipitate when heated to cooking temperatures in the digester [1,2]. The original single-vessel continuous digesters sold by Kamyr had an extra liquor heater as standard equipment to enable...

Time frequency analysis of sound from a maneuvering rotorcraft

NASA Astrophysics Data System (ADS)

Stephenson, James H.; Tinney, Charles E.; Greenwood, Eric; Watts, Michael E.

2014-10-01

The acoustic signatures produced by a full-scale, Bell 430 helicopter during steady-level-flight and transient roll-right maneuvers are analyzed by way of time-frequency analysis. The roll-right maneuvers comprise both a medium and a fast roll rate. Data are acquired using a single ground based microphone that are analyzed by way of the Morlet wavelet transform to extract the spectral properties and sound pressure levels as functions of time. The findings show that during maneuvering operations of the helicopter, both the overall sound pressure level and the blade-vortex interaction sound pressure level are greatest when the roll rate of the vehicle is at its maximum. The reduced inflow in the region of the rotor disk where blade-vortex interaction noise originates is determined to be the cause of the increase in noise. A local decrease in inflow reduces the miss distance of the tip vortex and thereby increases the BVI noise signature. Blade loading and advance ratios are also investigated as possible mechanisms for increased sound production, but are shown to be fairly constant throughout the maneuvers.

Improved electroacoustic dewatering (EAD) belt press for food products. Phase 3, Technical progress report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1994-02-01

Battelle`s electroacoustic dewatering (EAD) process improves the performance of mechanical dewatering processes for several food products (such as corn fiber) by superimposing electric and ultrasonic fields. EAD has the potential to save 0.027 to 0.035 quad/yr energy by 1995 in the food processing industry, which consumed 0.15 to 0.18 quad in 1986. This report covers Phase III for demonstrating the EAD prototype on corn wet milling products (corn fiber and gluten); only Task 1 (prototype preparation and planning) was completed. EAD performance was examined in the laboratory; availability of a test site was examined. The single-roll, postdewatering EAD belt pressmore » prototype can accept material predewatered by a screw press, centrifuge, or any other mechanical dewatering device. The two-belt system, utilizing a copper-polymer cathode belt, performed as well as the three-belt system used in Phase II.« less

New technology for recyclingmaterials from oily cold rollingmill sludge

NASA Astrophysics Data System (ADS)

Liu, Bo; Zhang, Shen-gen; Tian, Jian-jun; Pan, De-an; Meng, Ling; Liu, Yang

2013-12-01

Oily cold rolling mill (CRM) sludge is one of metallurgical industry solid wastes. The recycle of these wastes can not only protect the environment but also permit their reutilization. In this research, a new process of "hydrometallurgical treatment + hydrothermal synthesis" was investigated for the combined recovery of iron and organic materials from oily CRM sludge. Hydrometallurgical treatment, mainly including acid leaching, centrifugal separation, neutralization reaction, oxidizing, and preparation of hydrothermal reaction precursor, was first utilized for processing the sludge. Then, micaceous iron oxide (MIO) pigment powders were prepared through hydrothermal reaction of the obtained precursor in alkaline media. The separated organic materials can be used for fuel or chemical feedstock. The quality of the prepared MIO pigments is in accordance with the standards of MIO pigments for paints (ISO 10601-2007). This clean, effective, and economical technology offers a new way to recycle oily CRM sludge.

Mechanical and thermal properties of short-coirfiber-reinforced natural rubber/polyethylene composites

NASA Astrophysics Data System (ADS)

Xu, Zh. H.; Kong, Zh. N.

2014-07-01

Natural rubber (NR) and polyethylene (PE) composites were compounded with chemically treated coir fibers by using a heated two-roll mill. Two chemical treatments of the fibers — by silane and sodium hydroxide — were carried out to improve the interfacial adhesion between them and the polyethylene matrix. The mechanical properties of the composites obtained were evaluated and compared with those made from a neat polymer and untreated fibers. The mechanical properties of the composites, such as the tensile strength, Young's modulus, and the elongation at break, were examined, and their shrinkage and flame retardant characteristics were measured. From these experiments, the effect of plasma treatment on the mechanical-physical behavior of coconut-fiberreinforced NR/PE composites was identified. In addition, their thermal characteristics were evaluated, and the results showed a slight decrease in them with increasing content of coir fibers.

Structural optimisation of cage induction motors using finite element analysis

NASA Astrophysics Data System (ADS)

Palko, S.

The current trend in motor design is to have highly efficient, low noise, low cost, and modular motors with a high power factor. High torque motors are useful in applications like servo motors, lifts, cranes, and rolling mills. This report contains a detailed review of different optimization methods applicable in various design problems. Special attention is given to the performance of different methods, when they are used with finite element analysis (FEA) as an objective function, and accuracy problems arising from the numerical simulations. Also an effective method for designing high starting torque and high efficiency motors is presented. The method described in this work utilizes FEA combined with algorithms for the optimization of the slot geometry. The optimization algorithm modifies the position of the nodal points in the element mesh. The number of independent variables ranges from 14 to 140 in this work.

Tensile, swelling and morphological properties of bentonite-filled acrylonitrile butadiene rubber composites

NASA Astrophysics Data System (ADS)

Lotfi, Muhamad Nadhli Amin; Ismail, Hanafi; Othman, Nadras

2017-10-01

Tensile, swelling and morphological properties of bentonite filled acrylonitrile butadiene rubber (NBR/Bt) composites were studied. The experiments were conducted at room temperature by using two rolled mill, universal testing machine (INSTRON), and American Standard Testing Method (ASTM) D471 for compounding, tensile testing, and swelling test, respectively. Results obtained indicated that a better tensile strength, elongation at break and tensile modulus were recorded as compared to the pure NBR particularly up to 90 phr of Bt loading. However, swelling (%) exhibited the opposite trend where the liquid uptake by the composites was indirectly proportional with the increasing of Bt loading. Scanning electron microscopy (SEM) used on the tensile fractured surface of the NBR/Bt composites have shown that the fillers were well embedded in the NBR matrix, for Bt loading up to 90 phr. The agglomeration of fillers occurred for Bt loading exceeding 90 phr.

Effect of carbon black composition with sludge palm oil on the curing characteristic and mechanical properties of natural rubber/styrene butadiene rubber compound

NASA Astrophysics Data System (ADS)

Mohamed, R.; Nurazzi, N. Mohd; Huzaifah, M.

2017-07-01

This study was conducted to investigate the possibility of utilizing sludge palm oil (SPO) as processing oil, with various amount of carbon black as its reinforcing filler, and its effects on the curing characteristics and mechanical properties of natural rubber/styrene butadiene rubber (NR/SBR) compound. Rubber compound with fixed 15 pphr of SPO loading, and different carbon black loading from 20 to 50 pphr, was prepared using two roll mills. The cure characteristics and mechanical tests that have been conducted are the scorch and cure time analysis, tensile strength and tear strength. Scorch time (ts5) and cure time (t90) of the compound increases with the increasing carbon black loading. The mechanical properties of NR/SBR compound viz. the tensile strength, modulus at 300% strain and tear strength were also improved by the increasing carbon black loading.

Ultralow percolation threshold of single walled carbon nanotube-epoxy composites synthesized via an ionic liquid dispersant/initiator

NASA Astrophysics Data System (ADS)

Watters, Arianna L.; Palmese, Giuseppe R.

2014-09-01

Uniform dispersion of single walled carbon nanotubes (SWNTs) in an epoxy was achieved by a streamlined mechano-chemical processing method. SWNT-epoxy composites were synthesized using a room temperature ionic liquid (IL) with an imidazolium cation and dicyanamide anion. The novel approach of using ionic liquid that behaves as a dispersant for SWNTs and initiator for epoxy polymerization greatly simplifies nanocomposite synthesis. The material was processed using simple and scalable three roll milling. The SWNT dispersion of the resultant composite was evaluated by electron microscopy and electrical conductivity measurements in conjunction with percolation theory. Processing conditions were optimized to achieve the lowest possible percolation threshold, 4.29 × 10-5 volume fraction SWNTs. This percolation threshold is among the best reported in literature yet it was obtained using a streamlined method that greatly simplifies processing.

Morphological and mechanical properties of styrene butadiene rubber/nano copper nanocomposites

NASA Astrophysics Data System (ADS)

Harandi, Maryam Hadizadeh; Alimoradi, Fakhrodin; Rowshan, Gholamhussein; Faghihi, Morteza; Keivani, Maryam; Abadyan, Mohamadreza

In this research, rubber based nanocomposites with presence of nanoparticle has been studied. Styrene butadiene rubber (SBR)/nanocopper (NC) composites were prepared using two-roll mill method. Transmission electron microscope (TEM) and scanning electron microscope (SEM) images showed proper dispersion of NC in the SBR matrix without substantial agglomeration of nanoparticles. To evaluate the curing properties of nanocomposite samples, swelling and cure rheometric tests were conducted. Moreover, the rheological studies were carried out over a range of shear rates. The effect of NC particles was examined on the thermal behavior of the SBR using thermal gravimetric analysis (TGA). Furthermore, tensile tests were employed to investigate the capability of nanoparticles to enhance mechanical behavior of the compounds. The results showed enhancement in tensile properties with incorporation of NC to SBR matrix. Moreover, addition of NC increased shear viscosity and curing time of SBR composites.

Integrated process for the removal of emulsified oils from effluents in the steel industry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benito, J.M.; Rios, G.; Gutierrez, B.

1999-11-01

Emulsified oils contained in aqueous effluents from cold-rolling mills of the steel industry can be effectively removed via an integrated process consisting of a coagulation/flocculation stage followed by ultrafiltration of the resulting aqueous phase. The effects of CaCl{sub 2}, NaOH, and lime on the stability of different industrial effluents were studied in the coagulation experiments. The flocculants tested were inorganic prehydrolyzed aluminum salts and quaternary polyamines. Ultrafiltration of the aqueous phase from the coagulation/flocculation stage was carried out in a stirred cell using Amicon PM30 and XM300 organic membranes. Permeate fluxes were measured for industrial effluents to which the indicatedmore » coagulants and flocculants had been added. Oil concentrations in the permeate were 75% lower than the limits established by all European Union countries. Complete regeneration of the membrane was accomplished with an aqueous solution of a commercial detergent.« less

Varicose Veins in Women Cotton Workers. An Epidemiological Study in England and Egypt*

PubMed Central

Mekky, Siza; Schilling, R. S. F.; Walford, Joan

1969-01-01

The prevalence of varicose veins was studied in 504 women cotton workers in England and 467 in Egypt, by a standardized questionary and a specially developed method of examination. The English mill population showed a much higher prevalence of varicose veins than the Egyptian, probably owing to environmental rather than ethnic reasons. Among the European women the prevalence of varicose veins was significantly related to age, parity, body weight, type of corsetry, and occupation—that is, whether or not they stood at their work. After standardizing for the other variables there was a statistically significant excess of varicose veins in women wearing corsets and roll-ons compared with those wearing less-constrictive garments. After a similar standardization a significant excess was found in women who stood at their work compared with those whose jobs entailed walking or sitting. Imagesp593-a PMID:5798468

The scale invariant power spectrum of the primordial curvature perturbations from the coupled scalar tachyon bounce cosmos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Changhong; Cheung, Yeuk-Kwan E., E-mail: chellifegood@gmail.com, E-mail: cheung@nju.edu.cn

2014-07-01

We investigate the spectrum of cosmological perturbations in a bounce cosmos modeled by a scalar field coupled to the string tachyon field (CSTB cosmos). By explicit computation of its primordial spectral index we show the power spectrum of curvature perturbations, generated during the tachyon matter dominated contraction phase, to be nearly scale invariant. We propose a unified parameter space for a systematic study of inflationary and bounce cosmologies. The CSTB cosmos is dual-in Wands's sense-to slow-roll inflation as can be visualized with the aid of this parameter space. Guaranteed by the dynamical attractor behavior of the CSTB Cosmos, the scalemore » invariance of its power spectrum is free of the fine-tuning problem, in contrast to the slow-roll inflation model.« less

Wind-Tunnel Investigation at Low Speed of the Rolling Stability Derivatives of a 1/9-Scale Powered Model of the Convair XFY-1 Vertically Rising Airplane, TED No. NACA DE 373

NASA Technical Reports Server (NTRS)

Queijo, M. J.; Wolhart, Walter D.; Fletcher, H. S.

1953-01-01

An experimental investigation has been conducted in the Langley stability tunnel at low speed to determine the rolling stability derivatives of a 1/9-scale powered model of the Convair XFY-1 vertically rising airplane. Effects of thrust coefficient were investigated for the complete model and for certain components of the model. Effects of control deflections and of propeller blade angle were investigated for the complete model. Most of the tests were made through an angle-of-attack range from about -4deg to 29deg, and the thrust coefficient range was from 0 to 0.7. In order to expedite distribution of these data, no analysis of the data has been prepared for this paper.

Development of ODS FeCrAl alloys for accident-tolerant fuel cladding

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dryepondt, Sebastien N.; Hoelzer, David T.; Pint, Bruce A.

2015-09-18

FeCrAl alloys are prime candidates for accident-tolerant fuel cladding due to their excellent oxidation resistance up to 1400 C and good mechanical properties at intermediate temperature. Former commercial oxide dispersion strengthened (ODS) FeCrAl alloys such as PM2000 exhibit significantly better tensile strength than wrought FeCrAl alloys, which would alloy for the fabrication of a very thin (~250 m) ODS FeCrAl cladding and limit the neutronic penalty from the replacement of Zr-based alloys by Fe-based alloys. Several Fe-12-Cr-5Al ODS alloys where therefore fabricated by ball milling FeCrAl powders with Y2O3 and additional oxides such as TiO 2 or ZrO 2. Themore » new Fe-12Cr-5Al ODS alloys showed excellent tensile strength up to 800 C but limited ductility. Good oxidation resistance in steam at 1200 and 1400 C was observed except for one ODS FeCrAl alloy containing Ti. Rolling trials were conducted at 300, 600 C and 800 C to simulate the fabrication of thin tube cladding and a plate thickness of ~0.6mm was reached before the formation of multiple edge cracks. Hardness measurements at different stages of the rolling process, before and after annealing for 1h at 1000 C, showed that a thinner plate thickness could likely be achieved by using a multi-step approach combining warm rolling and high temperature annealing. Finally, new Fe-10-12Cr-5.5-6Al-Z gas atomized powders have been purchased to fabricate the second generation of low-Cr ODS FeCrAl alloys. The main goals are to assess the effect of O, C, N and Zr contents on the ODS FeCrAl microstructure and mechanical properties, and to optimize the fabrication process to improve the ductility of the 2nd gen ODS FeCrAl while maintaining good mechanical strength and oxidation resistance.« less

Axionic D3-D7 inflation

NASA Astrophysics Data System (ADS)

Burgess, C. P.; Cline, J. M.; Postma, M.

2009-03-01

We study the motion of a D3 brane moving within a Type IIB string vacuum compactified to 4D on K3 × T2/Z2 in the presence of D7 and O7 planes. We work within the effective 4D supergravity describing how the mobile D3 interacts with the lightest bulk moduli of the compactification, including the effects of modulus-stabilizing fluxes. We seek inflationary solutions to the resulting equations, performing our search numerically in order to avoid resorting to approximate parameterizations of the low-energy potential. We consider uplifting from D-terms and from the supersymmetry-breaking effects of anti-D3 branes. We find examples of slow-roll inflation (with anti-brane uplifting) with the mobile D3 moving along the toroidal directions, falling towards a D7-O7 stack starting from the antipodal point. The inflaton turns out to be a linear combination of the brane position and the axionic partner of the K3 volume modulus, and the similarity of the potential along the inflaton direction with that of racetrack inflation leads to the prediction ns <= 0.95 for the spectral index. The slow roll is insensitive to most of the features of the effective superpotential, and requires a one-in-104 tuning to ensure that the torus is close to square in shape. We also consider D-term inflation with the D3 close to the attractive D7, but find that for a broad (but not exhaustive) class of parameters the conditions for slow roll tend to destabilize the bulk moduli. In contrast to the axionic case, the best inflationary example of this kind requires the delicate adjustment of potential parameters (much more than the part-per-mille level), and gives inflation only at an inflection point of the potential (and so suffers from additional fine-tuning of initial conditions to avoid an overshoot problem).

Application of RNAMlet to surface defect identification of steels

NASA Astrophysics Data System (ADS)

Xu, Ke; Xu, Yang; Zhou, Peng; Wang, Lei

2018-06-01

As three main production lines of steels, continuous casting slabs, hot rolled steel plates and cold rolled steel strips have different surface appearances and are produced at different speeds of their production lines. Therefore, the algorithms for the surface defect identifications of the three steel products have different requirements for real-time and anti-interference. The existing algorithms cannot be adaptively applied to surface defect identification of the three steel products. A new method of adaptive multi-scale geometric analysis named RNAMlet was proposed. The idea of RNAMlet came from the non-symmetry anti-packing pattern representation model (NAM). The image is decomposed into a set of rectangular blocks asymmetrically according to gray value changes of image pixels. Then two-dimensional Haar wavelet transform is applied to all blocks. If the image background is complex, the number of blocks is large, and more details of the image are utilized. If the image background is simple, the number of blocks is small, and less computation time is needed. RNAMlet was tested with image samples of the three steel products, and compared with three classical methods of multi-scale geometric analysis, including Contourlet, Shearlet and Tetrolet. For the image samples with complicated backgrounds, such as continuous casting slabs and hot rolled steel plates, the defect identification rate obtained by RNAMlet was 1% higher than other three methods. For the image samples with simple backgrounds, such as cold rolled steel strips, the computation time of RNAMlet was one-tenth of the other three MGA methods, while the defect identification rates obtained by RNAMlet were higher than the other three methods.

Correlation of Microstructure and Texture in a Two-Phase High-Mn Twinning-Induced Plasticity Steel During Cold Rolling

NASA Astrophysics Data System (ADS)

Ashiq, Mohammad; Dhekne, Pushkar; Hamada, Atef Saad; Sahu, Puspendu; Mahato, B.; Minz, R. K.; Ghosh Chowdhury, Sandip; Pentti Karjalainen, L.

2017-10-01

The evolution of microstructure and texture of a two-phase austenite-ferrite twinning-induced plasticity steel during cold rolling was investigated and different deformation mechanisms were found to become active with increasing thickness reductions. Optical microscopy showed the formation of brass-type shear bands across several austenite grains at reductions greater than 50 pct. TEM observations reveal the presence of deformation twinning in austenite. The austenite phase initially shows the Cu-type texture, i.e., Cu {1 1 2}〈1 1 1〉, Goss {0 1 1}〈1 0 0〉 with a spread toward Brass {1 1 0}〈1 1 2〉. With continued cold rolling, the Cu {1 1 2}〈1 1 1〉 component moves toward CuT component {552}〈115〉 and the other two components increase in intensity. There is also emergence of {111} fiber after 90 pct cold rolling. The ferrite phase exhibits the evolution of ND-rotated Cube component {001}〈110〉 along with 〈110〉 fiber at lower as well as at higher rolling reductions. An exception is at 75 pct reduction, when the ferrite texture contains {111} fiber in place of 〈110〉 fiber with a weak rotated-Cube component. Phase fraction analysis by X-ray diffraction indicates a decrease in the austenite fraction up to 75 pct reduction followed by an increase at 90 pct reduction. After 90 pct cold rolling, the phase fraction is similar to that of the "as-received" state. Elongated grains of ferrite phase in finer dimensions after 90 pct cold rolling indicate softening within that phase; at similar stage, there are finer scale austenite grains mostly at the grain boundaries. The above has been suggested to be related with the adiabatic heating during cold rolling due to the high strain hardening of the austenite phase.

40 CFR 420.20 - Applicability; description of the sintering subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... resulting from sintering operations conducted by the heating of iron bearing wastes (mill scale and dust from blast furnaces and steelmaking furnaces) together with fine iron ore, limestone, and coke fines in...

40 CFR 420.20 - Applicability; description of the sintering subcategory.

Code of Federal Regulations, 2012 CFR

2012-07-01

... resulting from sintering operations conducted by the heating of iron bearing wastes (mill scale and dust from blast furnaces and steelmaking furnaces) together with fine iron ore, limestone, and coke fines in...

40 CFR 420.20 - Applicability; description of the sintering subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... resulting from sintering operations conducted by the heating of iron bearing wastes (mill scale and dust from blast furnaces and steelmaking furnaces) together with fine iron ore, limestone, and coke fines in...

40 CFR 420.20 - Applicability; description of the sintering subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... resulting from sintering operations conducted by the heating of iron bearing wastes (mill scale and dust from blast furnaces and steelmaking furnaces) together with fine iron ore, limestone, and coke fines in...

40 CFR 420.20 - Applicability; description of the sintering subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... resulting from sintering operations conducted by the heating of iron bearing wastes (mill scale and dust from blast furnaces and steelmaking furnaces) together with fine iron ore, limestone, and coke fines in...

Influence of crystallographic texture in X70 pipeline steels on toughness anisotropy and delamination

NASA Astrophysics Data System (ADS)

Al-Jabr, Haytham M.

The effects of microstructure and crystallographic texture in four commercially-produced API X70 pipeline steels and their relation to planar anisotropy of toughness and delamination were evaluated. The experimental steels were processed through either a hot strip mill, a Steckel mill, or a compact strip mill. Different processing routes were selected to obtain plates with potential variations in the microstructure and anisotropic characteristics. Tensile and Charpy impact testing were used to evaluate the mechanical properties in three orientations: longitudinal (L), transverse (T) and diagonal (D) with respect to the rolling direction to evaluate mechanical property anisotropy. The yield and tensile strengths were higher in the T orientation and toughness was lower in the D orientation for all plates. Delamination was observed in some of the ductile fracture surfaces of the impact samples. To further study the splitting behavior and effects on impact toughness, a modified impact test (MCVN) specimen with side grooves was designed to intensify induced stresses parallel to the notch root and thus facilitate evaluation of delamination. Scanning electron microscopy combined with electron backscattered diffraction (EBSD) were used to evaluate the grain size, microstructural constituents, and crystallographic texture to determine the factors leading to delamination and the anisotropy in toughness. The ferrite grain size is mainly responsible for the differences in DBTTs between the L and T orientations. The higher DBTT in the D orientation observed in pipeline steels is attributed to crystallographic texture. The higher DBTT in the D direction is due to the higher volume fraction of grains having their {100} planes parallel or close to the primary fracture plane for the D orientation. An equation based on a new "brittleness parameter," based on an assessment of grain orientations based on EBSD data, was developed to predict the changes in DBTTs with respect to sample orientation based on grain size and texture. The calculated DBTTs correlated well with the experimental values. The {001} and {113} components are the main preferred orientations that cause brittleness in the D direction, since their {001} planes make an angle less than 20° with the primary fracture plane of the samples oriented in the D direction. It was also concluded that delamination occurs due to banded bainite regions that were oriented such that their {001} planes make a small angle with the rolling plane leading to degradation in crack arrestability. The texture of the banded regions consisted of {001}, {113} or {111} orientations. It was concluded that the {001} and {113} orientations promote splitting because their fracture strengths in the normal direction are low. The {111} orientation has a calculated fracture strength more than twice the {001} and {113} orientations and therefore banded regions with the {111} texture are more susceptible to cleavage fracture perpendicular to the normal direction.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Odette, G Robert; Cunningham, Nicholas J., Wu, Yuan; Etienne, Auriane

The broad objective of this NEUP was to further develop a class of 12-15Cr ferritic alloys that are dispersion strengthened and made radiation tolerant by an ultrahigh density of Y-Ti-O nanofeatures (NFs) in the size range of less than 5 nm. We call these potentially transformable materials nanostructured ferritic alloys (NFAs). NFAs are typically processed by ball milling pre-alloyed rapidly solidified powders and yttria (Y2O3) powders. Proper milling effectively dissolves the Ti, Y and O solutes that precipitate as NFs during hot consolidation. The tasks in the present study included examining alternative processing paths, characterizing and optimizing the NFs andmore » investigating solid state joining. Alternative processing paths involved rapid solidification by gas atomization of Fe, 14% Cr, 3% W, and 0.4% Ti powders that are also pre-alloyed with 0.2% Y (14YWT), where the compositions are in wt.%. The focus is on exploring the possibility of minimizing, or even eliminating, the milling time, as well as producing alloys with more homogeneous distributions of NFs and a more uniform, fine grain size. Three atomization environments were explored: Ar, Ar plus O (Ar/O) and He. The characterization of powders and alloys occurred through each processing step: powder production by gas atomization; powder milling; and powder annealing or hot consolidation by hot isostatic pressing (HIPing) or hot extrusion. The characterization studies of the materials described here include various combinations of: a) bulk chemistry; b) electron probe microanalysis (EPMA); c) atom probe tomography (APT); d) small angle neutron scattering (SANS); e) various types of scanning and transmission electron microscopy (SEM and TEM); and f) microhardness testing. The bulk chemistry measurements show that preliminary batches of gas-atomized powders could be produced within specified composition ranges. However, EPMA and TEM showed that the Y is heterogeneously distributed and phase separated, but TEM, SANS and APT show that attritor milling for 20 to 40 h sufficiently mixes the Y. TEM, SANS and APT showed that subsequent powder annealing treatments result in the precipitation of a high density of NFs. All the annealed powder variants and HIP consolidated alloys had a bimodal distribution of grain sizes; however, APT and TEM show the presence of NFs in both large and small grains. Alloys extruded at 850°C contain a unimodal distribution of fine grains. The initial milling procedures in this study added a significant quantity of O as well as contaminant N to the powders. An improved milling procedure effectively eliminated the contamination resulting in lower O content that was insufficient to produce Y-Ti-O NFs in the size range below 3 nm. TEM showed that the low O resulted in fewer and larger oxide phases that are more highly enriched in Y, resulting in low Vicker's hardness values 250 kg/mm^2 compared to 443 kg/mm^2 in an alloy consolidated from the preliminary powders with higher O content. In order to overcome the problem of O deficiency, FeO additions during 40 h attritor milling were made to increase the O content to a nominal value of 0.135%. The annealed powder and corresponding 1150°C HIP and 850°C extrusion consolidated alloy showed a very uniform distribution of fine scale NFs. The HIP consolidated alloy had promising high temperature creep strength, but low toughness and a high ductile to brittle transition temperature (DBTT). An extruded and cross-rolled alloy processed at 850ºC, however, exhibited a lower DBTT. Also investigated were the effects of Ti and Y content on the NFs in alloys produced from conventionally milled powders that varied Y2O3 from 0.2 to 0.5 wt.% while maintaining Ti/Y atom ratios of 1.6, 2.4, and 3.1. SANS showed the volume fraction and number density of the NFs increases with Y and to a lesser extent Ti. Notably, the NF size and composition are relatively independent of the alloy Y and Ti content, except at the lowest Y2O3 concentration of 0.2 wt.%. An APT characterization of MA957 joined by friction stir welding (FSW) showed that this solid sate joining procedure had only a modest effect on the NF number density (N) and average diameter () compared to an as extruded sample. FSW appears to rearrange the NFs, which become highly aligned with sub-boundary and dislocation structures to an extent that are not observed in the as extruded case. The aligned NF structures are less apparent, but seem to persist after post weld annealing at 1150ºC for 3 h following which reduces N, consistent with a significant reduction in hardness. Lastly, several NFA materials, including MA957 and various 14YWT alloys, have been included in irradiation experiments performed at the Advanced Test Reactor, the JOYO sodium cooled fast reactor, the High Flux Isotope Reactor, and the SINQ spallation neut« less

From SL(5, ℝ) Yang-Mills theory to induced gravity

NASA Astrophysics Data System (ADS)

Assimos, T. S.; Pereira, A. D.; Santos, T. R. S.; Sobreiro, R. F.; Tomaz, A. A.; Otoya, V. J. Vasquez

From pure Yang-Mills action for the SL(5, ℝ) group in four Euclidean dimensions we obtain a gravity theory in the first order formalism. Besides the Einstein-Hilbert term, the effective gravity has a cosmological constant term, a curvature squared term, a torsion squared term and a matter sector. To obtain such geometrodynamical theory, asymptotic freedom and the Gribov parameter (soft BRST symmetry breaking) are crucial. Particularly, Newton and cosmological constant are related to these parameters and they also run as functions of the energy scale. One-loop computations are performed and the results are interpreted.

Engineered particles demonstrate improved flow properties at elevated drug loadings for direct compression manufacturing.

PubMed

Trementozzi, Andrea N; Leung, Cheuk-Yui; Osei-Yeboah, Frederick; Irdam, Erwin; Lin, Yiqing; MacPhee, J Michael; Boulas, Pierre; Karki, Shyam B; Zawaneh, Peter N

2017-05-15

Optimizing powder flow and compaction properties are critical for ensuring a robust tablet manufacturing process. The impact of flow and compaction properties of the active pharmaceutical ingredient (API) becomes progressively significant for higher drug load formulations, and for scaling up manufacturing processes. This study demonstrated that flow properties of a powder blend can be improved through API particle engineering, without critically impacting blend tabletability at elevated drug loadings. In studying a jet milled API (D 50 =24μm) and particle engineered wet milled API (D 50 =70μm and 90μm), flow functions of all API lots were similarly poor despite the vast difference in average particle size (ff c <4). This finding strays from the common notion that powder flow properties are directly correlated to particle size distribution. Upon adding excipients, however, clear trends in flow functions based on API particle size were observed. Wet milled API blends had a much improved flow function (ff c >10) compared with the jet milled API blends. Investigation of the compaction properties of both wet and jet milled powder blends also revealed that both jet and wet milled material produced robust tablets at the drug loadings used. The ability to practically demonstrate this uncommon observation that similarly poor flowing APIs can lead to a marked difference upon blending is important for pharmaceutical development. It is especially important in early phase development during API selection, and is advantageous particularly when material-sparing techniques are utilized. Copyright © 2017 Elsevier B.V. All rights reserved.

Pilot-scale comparison of thermophilic aerobic suspended carrier biofilm process and activated sludge process in pulp and paper mill effluent treatment.

PubMed

Suvilampi, J E; Rintala, J A

2004-01-01

Thermophilic aerobic treatment of settled pulp and paper mill effluent was studied under mill premises with two comparative pilot processes; suspended carrier biofilm process (SCBP) and activated sludge process (ASP). Full-scale mesophilic activated sludge process was a reference treatment. During the runs (61 days) hydraulic retention times (HRTs) were kept 13+/-5 h and 16+/-6 h for SCBP and ASP, respectively. Corresponding volumetric loadings rates (VLR) were 2.7+/-0.9 and 2.2+/-1.0 kg CODfilt m(-3)d(-1). Temperatures varied between 46 to 60 degrees C in both processes. Mesophilic ASP was operated with HRT of 36 h, corresponding VLR of 0.7 kg CODfilt m(-3)d(-1). Both SCBP and ASP achieved CODfilt (GF/A filtered) removals up to 85%, while the mesophilic ASP removal was 89+/-2%. NTU values were markedly higher (100-300) in thermophilic effluents than in mesophilic effluent (30). Effluent turbidity was highly dependent on temperature; in batch experiment mesophilic effluent sample had NTU values of 30 and 60 at 35 degrees C and 55 degrees C, respectively. As a conclusion, both thermophilic treatments gave high CODfilt removals, which were close to mesophilic process removal and were achieved with less than half of HRT.

3D lattice distortions and defect structures in ion-implanted nano-crystals

PubMed Central

Hofmann, Felix; Tarleton, Edmund; Harder, Ross J.; Phillips, Nicholas W.; Ma, Pui-Wai; Clark, Jesse N.; Robinson, Ian K.; Abbey, Brian; Liu, Wenjun; Beck, Christian E.

2017-01-01

Focussed Ion Beam (FIB) milling is a mainstay of nano-scale machining. By manipulating a tightly focussed beam of energetic ions, often gallium (Ga+), FIB can sculpt nanostructures via localised sputtering. This ability to cut solid matter on the nano-scale revolutionised sample preparation across the life, earth and materials sciences. Despite its widespread usage, detailed understanding of the FIB-induced structural damage, intrinsic to the technique, remains elusive. Here we examine the defects caused by FIB in initially pristine objects. Using Bragg Coherent X-ray Diffraction Imaging (BCDI), we are able to spatially-resolve the full lattice strain tensor in FIB-milled gold nano-crystals. We find that every use of FIB causes large lattice distortions. Even very low ion doses, typical of FIB imaging and previously thought negligible, have a dramatic effect. Our results are consistent with a damage microstructure dominated by vacancies, highlighting the importance of free-surfaces in determining which defects are retained. At larger ion fluences, used during FIB-milling, we observe an extended dislocation network that causes stresses far beyond the bulk tensile strength of gold. These observations provide new fundamental insight into the nature of the damage created and the defects that lead to a surprisingly inhomogeneous morphology. PMID:28383028

3D lattice distortions and defect structures in ion-implanted nano-crystals.

PubMed

Hofmann, Felix; Tarleton, Edmund; Harder, Ross J; Phillips, Nicholas W; Ma, Pui-Wai; Clark, Jesse N; Robinson, Ian K; Abbey, Brian; Liu, Wenjun; Beck, Christian E

2017-04-06

Focussed Ion Beam (FIB) milling is a mainstay of nano-scale machining. By manipulating a tightly focussed beam of energetic ions, often gallium (Ga + ), FIB can sculpt nanostructures via localised sputtering. This ability to cut solid matter on the nano-scale revolutionised sample preparation across the life, earth and materials sciences. Despite its widespread usage, detailed understanding of the FIB-induced structural damage, intrinsic to the technique, remains elusive. Here we examine the defects caused by FIB in initially pristine objects. Using Bragg Coherent X-ray Diffraction Imaging (BCDI), we are able to spatially-resolve the full lattice strain tensor in FIB-milled gold nano-crystals. We find that every use of FIB causes large lattice distortions. Even very low ion doses, typical of FIB imaging and previously thought negligible, have a dramatic effect. Our results are consistent with a damage microstructure dominated by vacancies, highlighting the importance of free-surfaces in determining which defects are retained. At larger ion fluences, used during FIB-milling, we observe an extended dislocation network that causes stresses far beyond the bulk tensile strength of gold. These observations provide new fundamental insight into the nature of the damage created and the defects that lead to a surprisingly inhomogeneous morphology.

Development of a nanosuspension for iv administration: From miniscale screening to a freeze dried formulation.

PubMed

Frank, Kerstin J; Boeck, Georg

2016-05-25

The aim was to develop a nanosuspension of the poorly soluble BI XX. The nanosuspension is intended for intravenous (iv) administration in preclinical studies and should not cause any unwanted side effects. Thus, only stabilizers that are accepted for iv application should be used and isotonicity, euhydria and the absence of living microorganisms were targeted. Suspensions were prepared in a ball-mill (mixing mill MM 400 from Retsch). There were various vials used as containers; HPLC-vials were used for the small scale screening of stabilizers and injection vials for preparation of larger quantities of the nanosuspensions. Particle size distribution was analyzed by laser diffraction measurement (Mastersizer 2000). Lyophilization was used for processing of the suspensions (Christ freeze dryer). Stable nanosuspensions (d90 remained <1μm up to 7days) were prepared with several FDA-accepted stabilizers. Freeze drying was evaluated for one formulation containing 2% of the API, 0.5% of arginine and 4% of mannitol. The particle size distribution before freeze drying and after re-dispersion was comparable. After milling for 2h, no living microorganisms were detected in the nanosuspension. Various FDA accepted excipients were identified which resulted in stable nanosuspensions of BI XX. The most stable formulation was successfully freeze dried. It was proven that milling in the ball-mill decreases the presence of living microorganisms. Copyright © 2016. Published by Elsevier B.V.

Development of flocculent Saccharomyces cerevisiae strain GYK-10 for the selective fermentation of glucose/fructose in sugar mills.

PubMed

Kato, Taku; Ohara, Satoshi; Fukushima, Yasuhiro; Sugimoto, Akira; Masuda, Takayuki; Yasuhara, Takaomi; Yamagishi, Hiromi

2016-07-01

Advances in glucose/fructose-selective ethanol production have successfully enhanced raw sugar extraction from sugarcane juice by converting inhibitory substances (i.e., glucose/fructose) into ethanol, which is removed by subsequent operations in cane sugar mills. However, the commercial implementation of this breakthrough process in existing cane sugar mills requires a yeast strain that (i) can be used in food production processes, (ii) exhibits stable saccharometabolic selectivity, and (iii) can be easily separated from the saccharide solution. In this study, we developed a suitable saccharometabolism-selective and flocculent strain, Saccharomyces cerevisiae GYK-10. We obtained a suitable yeast strain for selective fermentation in cane sugar mills using a yeast mating system. First, we crossed a haploid strain defective in sucrose utilization with a flocculent haploid strain. Next, we performed tetrad dissection of the resultant hybrid diploid strain and selected GYK-10 from various segregants by investigating the sucrose assimilation and flocculation capacity phenotypes. Ten consecutive fermentation tests of the GYK-10 strain using a bench-scale fermentor confirmed its suitability for the implementation of practical selective fermentation in a commercial sugar mill. The strain exhibited complete saccharometabolic selectivity and sustained flocculation, where it maintained a high ethanol yield and conversion rate throughout the test. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Estimating sawmill processing capacity for Tongass timber.

Treesearch

Kenneth A. Kilborn; Daniel J. Parrent; Robert D. Housley

2004-01-01

In spring 2001 and 2003, sawmill capacity and utilization information was collected directly from 20 producers (usually the largest and most active) in southeast Alaska. The estimated mill capacity in southeast Alaska for calendar year (CY) 2000 was 501,850 thousand board feet (MBF) (log scale) and for CY 2002 was 453,850 MBF (log scale). The actual production by these...

Note: Development of a small maglev-type antirolling system.

PubMed

Park, Cheol Hoon; Park, Hee Chang; Cho, Han Wook; Moon, Seok Jun; Chung, Tae Young

2010-05-01

Various passive and/or active antirolling devices have been used for suppressing the rolling motion of ships in the ocean. In this study, a maglev-type active mass driver (AMD) is developed for controlling the rolling motion of a shiplike structure. No friction is generated during the motion of this maglev-type AMD, as the moving mass is floated by the magnetic levitation force and displaced by the propulsion force generated by the linear motor. For verifying the feasibility of the proposed method, a small AMD having a moving mass of approximately 4.0 kg is constructed and used in a small-scale model of a catamaran. This paper presents the detailed design procedures and obtained experimental results. Our results show that the developed maglev-type AMD has the potential for use in controlling the rolling motion of ships and other oceanographic vessels.

Inflationary magnetogenesis with added helicity: constraints from non-Gaussianities

NASA Astrophysics Data System (ADS)

Caprini, Chiara; Chiara Guzzetti, Maria; Sorbo, Lorenzo

2018-06-01

In previous work (Caprini and Sorbo 2014 J. Cosmol. Astropart. Phys. JCAP10(2014)056), two of us have proposed a model of inflationary magnetogenesis based on a rolling auxiliary field able both to account for the magnetic fields inferred by the (non) observation of gamma-rays from blazars, and to start the galactic dynamo, without incurring in any strong coupling or strong backreaction regime. Here we evaluate the correction to the scalar spectrum and bispectrum with respect to single-field slow-roll inflation generated in that scenario. The strongest constraints on the model originate from the non-observation of a scalar bispectrum. Nevertheless, even when those constraints are taken into consideration, the scenario can successfully account for the observed magnetic fields as long as the energy scale of inflation is smaller than GeV, under some conditions on the slow roll of the auxiliary scalar field.

Flight Control System Analysis and Design for a Remotely Piloted Vehicle with Thrust Vectoring Unit.

DTIC Science & Technology

1980-12-01

about the X-axis (slug-ft 2) Ixz Product of inertia (slug-ft 2 ) ly Moi,;ent of inertia about Y-axis (slug-ft 2) Iz Moment of inertia about Z-axis (slug...domain n Load factor (g’s) P Roll rate (rad/sec) xi p Perturbation roll rate (rad/sec) Q Pitch rate (rad/sec) q Perturbation pitch rate (rad/sec...was decided to employ a scale factor of 1.75 in increasing the vertical tail area. This choice was somewhat aruitrary since no documentation could be

Roll Compaction/Dry Granulation of Dibasic Calcium Phosphate Anhydrous-Does the Morphology of the Raw Material Influence the Tabletability of Dry Granules?

PubMed

Grote, Simon; Kleinebudde, Peter

2018-04-01

The influence of raw material particle morphology on the tabletabilty of dry granules was investigated. Therefore, dibasic calcium phosphate anhydrous was used as a model material. One milled grade, 2 agglomerated grades with different porosities, and a functionalized structure, that is, an agglomerate formed by very small primary particles, were included. Particle size, density, and specific surface area of raw materials were measured. The starting materials and 2 fractions of dry granules were compressed to tablets. The tabletability of granules was compared to that of the powders and the influence of specific compaction force, granule size, and lubrication on tablet tensile strength was evaluated. All materials showed a loss in tabletability induced by a previous compaction step but to a varying extent. Only in case of the functionalized calcium phosphate morphology, this effect depended on the specific compaction force. In contrast to the other materials, the tabletability of functionalized calcium phosphate was influenced by the granule size. This effect was not related to an overlubrication as internal and external lubrication resulted in similar tensile strengths. A clear influence of the particle morphology on tablet strength was demonstrated by the study. The functionalized structure showed aspects of a more plastic deformation behavior. The functionalized dibasic calcium phosphate and the more porous agglomerate performed as potential filler/binder in the field of roll compaction/dry granulation. Copyright © 2018 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Roll-to-Roll Continuous Manufacturing Multifunctional Nanocomposites by Electric-Field-Assisted "Z" Direction Alignment of Graphite Flakes in Poly(dimethylsiloxane).

PubMed

Guo, Yuanhao; Chen, Yuwei; Wang, Enmin; Cakmak, Miko

2017-01-11

A roll-to-roll continuous process was developed to manufacture large-scale multifunctional poly(dimethylsiloxane) (PDMS) films embedded with thickness direction ("Z" direction) aligned graphite nanoparticles by application of electric field. The kinetics of particle "Z" alignment and chain formation was studied by tracking the real-time change of optical light transmission through film thickness direction. Benefiting from the anisotropic structure of aligned particle chains, the electrical and thermal properties of the nanocomposites were dramatically enhanced through the thickness direction as compared to those of the nanocomposites containing the same particle loading without electrical field alignment. With 5 vol % graphite loading, 250 times higher electrical conductivity, 43 times higher dielectric permittivity, and 1.5 times higher thermal conductivity was achieved in the film thickness direction after the particles were aligned under electrical field. Moreover, the aligned nanocomposites with merely 2 vol % graphite particles exhibit even higher electric conductivity and dielectric permittivity than those of the nonaligned nanocomposites at random percolation threshold (10 vol % particles), as the "electric-field-directed" percolation threshold concentration is substantially decreased using this process. As the graphite loading increases to 20 vol %, the aligned nanocomposites exhibit thermal conductivity as high as 6.05 W/m·K, which is 35 times the thermal conductivity of pure matrix. This roll-to-roll electric field continuous process provides a simple, low-cost, and commercially viable method to manufacture multifunctional nanocomposites for applications as embedded capacitor, electromagnetic (EM) shielding, and thermal interface materials.

Sparsity-optimized separation of body waves and ground-roll by constructing dictionaries using tunable Q-factor wavelet transforms with different Q-factors

NASA Astrophysics Data System (ADS)

Chen, Xin; Chen, Wenchao; Wang, Xiaokai; Wang, Wei

2017-10-01

Low-frequency oscillatory ground-roll is regarded as one of the main regular interference waves, which obscures primary reflections in land seismic data. Suppressing the ground-roll can reasonably improve the signal-to-noise ratio of seismic data. Conventional suppression methods, such as high-pass and various f-k filtering, usually cause waveform distortions and loss of body wave information because of their simple cut-off operation. In this study, a sparsity-optimized separation of body waves and ground-roll, which is based on morphological component analysis theory, is realized by constructing dictionaries using tunable Q-factor wavelet transforms with different Q-factors. Our separation model is grounded on the fact that the input seismic data are composed of low-oscillatory body waves and high-oscillatory ground-roll. Two different waveform dictionaries using a low Q-factor and a high Q-factor, respectively, are confirmed as able to sparsely represent each component based on their diverse morphologies. Thus, seismic data including body waves and ground-roll can be nonlinearly decomposed into low-oscillatory and high-oscillatory components. This is a new noise attenuation approach according to the oscillatory behaviour of the signal rather than the scale or frequency. We illustrate the method using both synthetic and field shot data. Compared with results from conventional high-pass and f-k filtering, the results of the proposed method prove this method to be effective and advantageous in preserving the waveform and bandwidth of reflections.

Conjugated Polymers Via Direct Arylation Polymerization in Continuous Flow: Minimizing the Cost and Batch-to-Batch Variations for High-Throughput Energy Conversion.

PubMed

Gobalasingham, Nemal S; Carlé, Jon E; Krebs, Frederik C; Thompson, Barry C; Bundgaard, Eva; Helgesen, Martin

2017-11-01

Continuous flow methods are utilized in conjunction with direct arylation polymerization (DArP) for the scaled synthesis of the roll-to-roll compatible polymer, poly[(2,5-bis(2-hexyldecyloxy)phenylene)-alt-(4,7-di(thiophen-2-yl)-benzo[c][1,2,5]thiadiazole)] (PPDTBT). PPDTBT is based on simple, inexpensive, and scalable monomers using thienyl-flanked benzothiadiazole as the acceptor, which is the first β-unprotected substrate to be used in continuous flow via DArP, enabling critical evaluation of the suitability of this emerging synthetic method for minimizing defects and for the scaled synthesis of high-performance materials. To demonstrate the usefulness of the method, DArP-prepared PPDTBT via continuous flow synthesis is employed for the preparation of indium tin oxide (ITO)-free and flexible roll-coated solar cells to achieve a power conversion efficiency of 3.5% for 1 cm 2 devices, which is comparable to the performance of PPDTBT polymerized through Stille cross coupling. These efforts demonstrate the distinct advantages of the continuous flow protocol with DArP avoiding use of toxic tin chemicals, reducing the associated costs of polymer upscaling, and minimizing batch-to-batch variations for high-quality material. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Inflation with Whip-Shaped Suppressed Scalar Power Spectra

NASA Astrophysics Data System (ADS)

Hazra, Dhiraj Kumar; Shafieloo, Arman; Smoot, George F.; Starobinsky, Alexei A.

2014-08-01

Motivated by the idea that inflation occurs at the grand unified theory symmetry breaking scale, in this Letter we construct a new class of large field inflaton potentials where the inflaton starts with a power law potential; after an initial period of relatively fast roll that lasts until after a few e folds inside the horizon it transits to the attractor of the slow roll part of the potential with a lower power. Because of the initial fast roll stages of inflation, we find a suppression in scalar primordial power at large scales and at the same time the choice of the potential can provide us a tensor primordial spectrum with a high amplitude. This suppression in scalar power with a large tensor-to-scalar ratio helps us to reconcile the Planck and BICEP2 data in a single framework. We find that a transition from a cubic to quadratic form of inflaton potential generates an appropriate suppression in the power of the scalar primordial spectrum that provides a significant improvement in fit compared to the power law model when compared with Planck and BICEP2 data together. We calculate the extent of non-Gaussianity, specifically, the bispectrum for the best fit potential, and show that it is consistent with Planck bispectrum constraints.

Low-Speed Flight Dynamic Tests and Analysis of the Orion Crew Module Drogue Parachute System

NASA Technical Reports Server (NTRS)

Hahne, David E.; Fremaux, C. Michael

2008-01-01

A test of a dynamically scaled model of the NASA Orion Crew Module (CM) with drogue parachutes was conducted in the NASA-Langley 20-Foot Vertical Spin Tunnel. The primary test objective was to assess the ability of the Orion Crew Module drogue parachute system to adequately stabilize the CM and reduce angular rates at low subsonic Mach numbers. Two attachment locations were tested: the current design nominal and an alternate. Experimental results indicated that the alternate attachment location showed a somewhat greater tendency to attenuate initial roll rate and reduce roll rate oscillations than the nominal location. Comparison of the experimental data to a Program To Optimize Simulated Trajectories (POST II) simulation of the experiment yielded results for the nominal attachment point that indicate differences between the low-speed pitch and yaw damping derivatives in the aerodynamic database and the physical model. Comparisons for the alternate attachment location indicate that riser twist plays a significant role in determining roll rate attenuation characteristics. Reevaluating the impact of the alternate attachment points using a simulation modified to account for these results showed significantly reduced roll rate attenuation tendencies when compared to the original simulation. Based on this modified simulation the alternate attachment point does not appear to offer a significant increase in allowable roll rate over the nominal configuration.

Rolling up of Large-scale Laminar Vortex Ring from Synthetic Jet Impinging onto a Wall

NASA Astrophysics Data System (ADS)

Xu, Yang; Pan, Chong; Wang, Jinjun; Flow Control Lab Team

2015-11-01

Vortex ring impinging onto a wall exhibits a wide range of interesting behaviors. The present work devotes to an experimental investigation of a series of small-scale vortex rings impinging onto a wall. These laminar vortex rings were generated by a piston-cylinder driven synthetic jet in a water tank. Laser Induced Fluorescence (LIF) and Particle Image Velocimetry (PIV) were used for flow visualization/quantification. A special scenario of vortical dynamic was found for the first time: a large-scale laminar vortex ring is formed above the wall, on the outboard side of the jet. This large-scale structure is stable in topology pattern, and continuously grows in strength and size along time, thus dominating dynamics of near wall flow. To quantify its spatial/temporal characteristics, Finite-Time Lyapunov Exponent (FTLE) fields were calculated from PIV velocity fields. It is shown that the flow pattern revealed by FTLE fields is similar to the visualization. The size of this large-scale vortex ring can be up to one-order larger than the jet vortices, and its rolling-up speed and entrainment strength was correlated to constant vorticity flux issued from the jet. This work was supported by the National Natural Science Foundation of China (Grants No.11202015 and 11327202).

Cosmological perturbations and noncommutative tachyon inflation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu Daojun; Li Xinzhou

2004-12-15

The motivation for studying the rolling tachyon and noncommutative inflation comes from string theory. In the tachyon inflation scenario, metric perturbations are created by tachyon field fluctuations during inflation. We drive the exact mode equation for scalar perturbations of the metric and investigate the cosmological perturbations in the commutative and noncommutative inflationary spacetime driven by the tachyon field which have a Born-Infeld Lagrangian. Although at lowest order the predictions of tachyon inflation are no different than those from standard slow-roll inflation, due to the modified inflationary dynamics there exists modifications to the power spectra of fluctuations generated during inflation. Inmore » the noncommutative tachyon inflation scenario, the stringy noncommutativity of spacetime results in corrections to the primordial power spectrum that lead to a spectral index that is greater than 1 on large scales and less than 1 on small scales as the first-year results of the Wilkinson Microwave Anisotropy Probe indicate.« less

Dynamic response characteristics of two transport models tested in the National Transonic Facility

NASA Technical Reports Server (NTRS)

Young, Clarence P., Jr.

1993-01-01

This paper documents recent experiences with measuring the dynamic response characteristics of a commercial transport and a military transport model during full scale Reynolds number tests in the National Transonic Facility. Both models were limited in angle of attack while testing at full scale Reynolds number and cruise Mach number due to pitch or stall buffet response. Roll buffet (wing buzz) was observed for both models at certain Mach numbers while testing at high Reynolds number. Roll buffet was more severe and more repeatable for the military transport model at cruise Mach number. Miniature strain-gage type accelerometers were used for the first time for obtaining dynamic data as a part of the continuing development of miniature dynamic measurements instrumentation for cryogenic applications. This paper presents the results of vibration measurements obtained for both the commercial and military transport models and documents the experience gained in the use of miniature strain gage type accelerometers.

Full-scale semi-span tests of an advanced NLF business jet wing

NASA Technical Reports Server (NTRS)

Hahne, David E.; Jordan, Frank L., Jr.; Davis, Patrick J.; Muchmore, C. Byram

1987-01-01

An investigation has been conducted in the NASA Langley Research Center's 30- by 60-Foot Wind Tunnel on a full-scale semispan model to evaluate and document the low-speed, high-lift characteristics of a business-jet class wing utilizing the HSNLF(1)-0213 airfoil section and a single slotted flap system. In addition to the high-lift studies, evaluations of boundary layer transition effects, the effectiveness of a segmented leading-edge droop for improved stall/spin resistance, and roll control effectiveness with and without flap deflection were made. The wind-tunnel investigation showed that deployment of a single-slotted trailing-edge flap provided substantial increments in lift. Fixed transition studies indicated no adverse effects on lift and pitching-moment characteristics for either the cruise or landing configuration. Subscale roll damping tests also indicated that stall/spin resistance could be enhanced through the use of a properly designed leading-edge droop.

Utilizing hydrologic, statistical, and geochemical tools to assess uranium mobility in surface and near-surface environments

NASA Astrophysics Data System (ADS)

Naftz, D. L.; Walton-Day, K. E.; Fuller, C.; Dam, W. L.; Briggs, M. A.; Snyder, T.

2015-12-01

Legacy uranium (U) mining and processing activities have resulted in soil and water contamination on Federal, state, and tribal lands in the western United States. Sites include legacy mill sites associated with U extraction now managed by the Department of Energy and thousands of waste dumps associated with U exploration, mining, and processing. Recently (2012), over 400,000 hectares of federally managed land in northern Arizona was withdrawn from consideration of mining for a 20-year period to protect the Grand Canyon watershed from potentially adverse effects of U mineral exploration and development. Ore from active and recently active U mines in the Colorado Plateau, the Henry Mountains Complex, and the Arizona Strip is transported to the only currently (2015) active conventional mill site in the western United States, located in Utah. Previous and ongoing U.S. Geological Survey assessments to examine U mobility at a variety of legacy and active sites associated with ore exploration, extraction, and processing will be presented as field-scale examples. Topics associated with site investigations will include: (1) offsite migration of radionuclides associated with the operation of the White Mesa U mill; (2) long-term contaminant transport from legacy U waste dumps on Bureau of Land Management regulated land in Utah; (3) application of incremental soil sampling techniques to determine pre- and post-mining radionuclide levels associated with planned and operating U mines in northern Arizona; (4) application of fiber optic digital temperature sensing equipment to identify areas where shallow groundwater containing elevated U levels may be discharging to a river adjacent to a reclaimed mill site in central Wyoming; and (5) field-scale manipulation of groundwater chemistry to limit U migration from a legacy upgrader site in southeastern Utah.

The application of advanced oxidation technologies to the treatment of effluents from the pulp and paper industry: a review.

PubMed

Hermosilla, Daphne; Merayo, Noemí; Gascó, Antonio; Blanco, Ángeles

2015-01-01

The paper industry is adopting zero liquid effluent technologies to reduce freshwater use and meet environmental regulations, which implies closure of water circuits and the progressive accumulation of pollutants that must be removed before water reuse and final wastewater discharge. The traditional water treatment technologies that are used in paper mills (such as dissolved air flotation or biological treatment) are not able to remove recalcitrant contaminants. Therefore, advanced water treatment technologies, such as advanced oxidation processes (AOPs), are being included in industrial wastewater treatment chains aiming to either improve water biodegradability or its final quality. A comprehensive review of the current state of the art regarding the use of AOPs for the treatment of the organic load of effluents from the paper industry is herein addressed considering mature and emerging treatments for a sustainable water use in this sector. Wastewater composition, which is highly dependent on the raw materials being used in the mills, the selected AOP itself, and its combination with other technologies, will determine the viability of the treatment. In general, all AOPs have been reported to achieve good organic removal efficiencies (COD removal >40%, and about an extra 20% if AOPs are combined with biological stages). Particularly, ozonation has been the most extensively reported and successfully implemented AOP at an industrial scale for effluent treatment or reuse within pulp and paper mills, although Fenton processes (photo-Fenton particularly) have actually addressed better oxidative results (COD removal ≈ 65-75%) at a lab scale, but still need further development at a large scale.

Infrared singularities in Landau gauge Yang-Mills theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alkofer, Reinhard; Huber, Markus Q.; Schwenzer, Kai

2010-05-15

We present a more detailed picture of the infrared regime of Landau-gauge Yang-Mills theory. This is done within a novel framework that allows one to take into account the influence of finite scales within an infrared power counting analysis. We find that there are two qualitatively different infrared fixed points of the full system of Dyson-Schwinger equations. The first extends the known scaling solution, where the ghost dynamics is dominant and gluon propagation is strongly suppressed. It features in addition to the strong divergences of gluonic vertex functions in the previously considered uniform scaling limit, when all external momenta tendmore » to zero, also weaker kinematic divergences, when only some of the external momenta vanish. The second solution represents the recently proposed decoupling scenario where the gluons become massive and the ghosts remain bare. In this case we find that none of the vertex functions is enhanced, so that the infrared dynamics is entirely suppressed. Our analysis also provides a strict argument why the Landau-gauge gluon dressing function cannot be infrared divergent.« less

Roll-to-roll-compatible, flexible, transparent electrodes based on self-nanoembedded Cu nanowires using intense pulsed light irradiation

NASA Astrophysics Data System (ADS)

Zhong, Zhaoyang; Woo, Kyoohee; Kim, Inhyuk; Hwang, Hyewon; Kwon, Sin; Choi, Young-Man; Lee, Youngu; Lee, Taik-Min; Kim, Kwangyoung; Moon, Jooho

2016-04-01

Copper nanowire (Cu NW)-based flexible transparent conductive electrodes (FTCEs) have been investigated in detail for use in various applications such as flexible touch screens, organic photovoltaics and organic light-emitting diodes. In this study, hexadecylamine (HDA) adsorbed onto the surface of NWs is changed into polyvinylpyrrolidone (PVP) via a ligand exchange process; the high-molecular-weight PVP enables high dispersion stability. Intense pulsed light (IPL) irradiation is used to remove organic species present on the surface of the NWs and to form direct connections between the NWs rapidly without any atmospheric control. NWs are self-nanoembedded into a plastic substrate after IPL irradiation, which results in a smooth surface, strong NW/substrate adhesion, excellent mechanical flexibility and enhanced oxidation stability. Moreover, Cu NW FTCEs with high uniformities are successfully fabricated on a large area (150 mm × 200 mm) via successive IPL irradiation that is synchronized with the motion of the sample stage. This study demonstrates the possibility of roll-to-roll-based, large-scale production of low-cost, high-performance Cu NW-based FTCEs.Copper nanowire (Cu NW)-based flexible transparent conductive electrodes (FTCEs) have been investigated in detail for use in various applications such as flexible touch screens, organic photovoltaics and organic light-emitting diodes. In this study, hexadecylamine (HDA) adsorbed onto the surface of NWs is changed into polyvinylpyrrolidone (PVP) via a ligand exchange process; the high-molecular-weight PVP enables high dispersion stability. Intense pulsed light (IPL) irradiation is used to remove organic species present on the surface of the NWs and to form direct connections between the NWs rapidly without any atmospheric control. NWs are self-nanoembedded into a plastic substrate after IPL irradiation, which results in a smooth surface, strong NW/substrate adhesion, excellent mechanical flexibility and enhanced oxidation stability. Moreover, Cu NW FTCEs with high uniformities are successfully fabricated on a large area (150 mm × 200 mm) via successive IPL irradiation that is synchronized with the motion of the sample stage. This study demonstrates the possibility of roll-to-roll-based, large-scale production of low-cost, high-performance Cu NW-based FTCEs. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr00444j

Characterization of printed planar electromagnetic coils using digital extrusion and roll-to-roll flexographic processes

NASA Astrophysics Data System (ADS)

Rickard, Scott

Electromagnets are a crucial component in a wide range of more complex electrical devices due to their ability to turn electrical energy into mechanical energy and vice versa. The trend for electronics becoming smaller and lighter has led to increased interest in using flat, planar electromagnetic coils, which have been shown to perform better at scaled down sizes. The two-dimensional geometry of a planar electromagnetic coil yields itself to be produced by a roll-to-roll additive manufacturing process. The emergence of the printed electronics field, which uses traditional printing processes to pattern functional inks, has led to new methods of mass-producing basic electrical components. The ability to print a planar electromagnetic coil using printed electronics could rival the traditional subtractive and semi-subtractive PCB process of manufacturing. The ability to print lightweight planar electromagnetic coils on flexible substrates could lead to their inclusion into intelligent packaging applications and could have specific use in actuating devices, transformers, and electromagnetic induction applications such as energy harvesting or wireless charging. In attempts to better understand the limitations of printing planar electromagnetic coils, the effect that the design parameters of the planar coils have on the achievable magnetic field strength were researched. A comparison between prototyping methods of digital extrusion and manufacturing scale flexographic printing are presented, discussing consistency in the printed coils and their performance in generating magnetic fields. A method to predict the performance of these planar coils is introduced to allow for design within required needs of an application. Results from the research include a demonstration of a printed coil being used in a flat speaker design, working off of actuating principles.

Large-area, lightweight and thick biomimetic composites with superior material properties via fast, economic, and green pathways.

PubMed

Walther, Andreas; Bjurhager, Ingela; Malho, Jani-Markus; Pere, Jaakko; Ruokolainen, Janne; Berglund, Lars A; Ikkala, Olli

2010-08-11

Although remarkable success has been achieved to mimic the mechanically excellent structure of nacre in laboratory-scale models, it remains difficult to foresee mainstream applications due to time-consuming sequential depositions or energy-intensive processes. Here, we introduce a surprisingly simple and rapid methodology for large-area, lightweight, and thick nacre-mimetic films and laminates with superior material properties. Nanoclay sheets with soft polymer coatings are used as ideal building blocks with intrinsic hard/soft character. They are forced to rapidly self-assemble into aligned nacre-mimetic films via paper-making, doctor-blading or simple painting, giving rise to strong and thick films with tensile modulus of 45 GPa and strength of 250 MPa, that is, partly exceeding nacre. The concepts are environmentally friendly, energy-efficient, and economic and are ready for scale-up via continuous roll-to-roll processes. Excellent gas barrier properties, optical translucency, and extraordinary shape-persistent fire-resistance are demonstrated. We foresee advanced large-scale biomimetic materials, relevant for lightweight sustainable construction and energy-efficient transportation.

Students' Pilot Laboratory for Homogeneous Chemical Reactor Analysis and Design in Olive Mill Wastewater Treatment

ERIC Educational Resources Information Center

Ochando-Pulido, J. M.

2017-01-01

The Chemical Engineering Department at the University of Granada have endeavored to make a number of high quality experiments to familiarize our students with our latest research and also scale-up of processes. A pilot-scale wastewater treatment plant was set-up to give students a close practical view of the treatments of effluents by-produced in…

Sodium Ion Dynamics in the Magnetospheric Flanks of Mercury

NASA Astrophysics Data System (ADS)

Aizawa, S.; Delcourt, D.; Terada, N.

2018-05-01

We examine the particle transport via the Kelvin-Helmholtz instability by using simulation. The heavy ions of planetary origin such as Na+ may experience prominent nonadiabatic energization as they ExB drift across large-scale rolled up vortices.

Comparison of roll-to-roll replication approaches for microfluidic and optical functions in lab-on-a-chip diagnostic devices

NASA Astrophysics Data System (ADS)

Brecher, Christian; Baum, Christoph; Bastuck, Thomas

2015-03-01

Economically advantageous microfabrication technologies for lab-on-a-chip diagnostic devices substituting commonly used glass etching or injection molding processes are one of the key enablers for the emerging market of microfluidic devices. On-site detection in fields of life sciences, point of care diagnostics and environmental analysis requires compact, disposable and highly functionalized systems. Roll-to-roll production as a high volume process has become the emerging fabrication technology for integrated, complex high technology products within recent years (e.g. fuel cells). Differently functionalized polymer films enable researchers to create a new generation of lab-on-a-chip devices by combining electronic, microfluidic and optical functions in multilayer architecture. For replication of microfluidic and optical functions via roll-to-roll production process competitive approaches are available. One of them is to imprint fluidic channels and optical structures of micro- or nanometer scale from embossing rollers into ultraviolet (UV) curable lacquers on polymer substrates. Depending on dimension, shape and quantity of those structures there are alternative manufacturing technologies for the embossing roller. Ultra-precise diamond turning, electroforming or casting polymer materials are used either for direct structuring or manufacturing of roller sleeves. Mastering methods are selected for application considering replication quality required and structure complexity. Criteria for the replication quality are surface roughness and contour accuracy. Structure complexity is evaluated by shapes producible (e.g. linear, circular) and aspect ratio. Costs for the mastering process and structure lifetime are major cost factors. The alternative replication approaches are introduced and analyzed corresponding to the criteria presented. Advantages and drawbacks of each technology are discussed and exemplary applications are presented.

Preliminary metallographic studies of ball fatigue under rolling-contact conditions

NASA Technical Reports Server (NTRS)

Bear, H Robert; Butler, Robert H

1957-01-01

The metallurgical results produced on balls tested in the rolling-contact fatigue spin rig were studied by metallographic examination. Origin and progression of fatigue failures were observed. These evaluations were made on SAE 52100 and AISI M-1 balls fatigue tested at room temperature (80 F) and 200 to 250 F. Most failures originated subsurface in shear; inclusions, structure changes, and directionalism adversely affected ball fatigue life. Structures in the maximum-shear-stress region of the balls of both materials were stable at room temperature and unstable at 200 to 250 F. Failures were of the same type as those found in full-scale bearings.

ELECTROCHEMICAL ARSENIC REMEDIATION IN RURAL BANGLADESH

EPA Science Inventory

In Year 1, we built a bench-scale continuous flow prototype (dubbed “Sushi” for its sushi-like electrode roll) and completed preliminary field trials in Bangladesh. We were also able to leverage additional funding to complete preliminary field trials in arsenic-...

Achieving zero waste of municipal incinerator fly ash by melting in electric arc furnaces while steelmaking.

PubMed

Yang, Gordon C C; Chuang, Tsun-Nan; Huang, Chien-Wen

2017-04-01

The main objective of this work was to promote zero waste of municipal incinerator fly ash (MIFA) by full-scale melting in electric arc furnaces (EAFs) of steel mini mills around the world. MIFA, generally, is considered as a hazardous waste. Like in many countries, MIFA in Taiwan is first solidified/stabilized and then landfilled. Due to the scarcity of landfill space, the cost of landfilling increases markedly year by year in Taiwan. This paper presents satisfactory results of treating several hundred tons of MIFA in a full-scale steel mini mill using the approach of "melting MIFA while EAF steelmaking", which is somewhat similar to "molten salt oxidation" process. It was found that this practice yielded many advantages such as (1) about 18wt% of quicklime requirement in EAF steelmaking can be substituted by the lime materials contained in MIFA; (2) MIFA would totally end up as a material in fractions of recyclable EAF dust, oxidized slag and reduced slag; (3) no waste is needed for landfilling; and (4) a capital cost saving through the employment of existing EAFs in steel mini mills instead of building new melting plants for the treatment of MIFA. Thus, it is technically feasible to achieve zero waste of MIFA by the practice of this innovative melting technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

Trend and current practices of palm oil mill effluent polishing: Application of advanced oxidation processes and their future perspectives.

PubMed

Bello, Mustapha Mohammed; Abdul Raman, Abdul Aziz

2017-08-01

Palm oil processing is a multi-stage operation which generates large amount of effluent. On average, palm oil mill effluent (POME) may contain up to 51, 000 mg/L COD, 25,000 mg/L BOD, 40,000 TS and 6000 mg/L oil and grease. Due to its potential to cause environmental pollution, palm oil mills are required to treat the effluent prior to discharge. Biological treatments using open ponding system are widely used for POME treatment. Although these processes are capable of reducing the pollutant concentrations, they require long hydraulic retention time and large space, with the effluent frequently failing to satisfy the discharge regulation. Due to more stringent environmental regulations, research interest has recently shifted to the development of polishing technologies for the biologically-treated POME. Various technologies such as advanced oxidation processes, membrane technology, adsorption and coagulation have been investigated. Among these, advanced oxidation processes have shown potentials as polishing technologies for POME. This paper offers an overview on the POME polishing technologies, with particularly emphasis on advanced oxidation processes and their prospects for large scale applications. Although there are some challenges in large scale applications of these technologies, this review offers some perspectives that could help in overcoming these challenges. Copyright © 2017 Elsevier Ltd. All rights reserved.

The development of compact electroactive polymer actuators suitable for use in full page Braille displays

NASA Astrophysics Data System (ADS)

Gorny, Lee J.; Zellers, Brian C.; Lin, Minren; Liu, Sheng; Zhang, Qiming M.

2010-04-01

Piezoceramic actuators, presently used in commercial Braille displays, are limited by the material's relatively small strain and brittle nature. For this reason, it is a challenge to develop full page, compact, graphic Braille displays that are affordable. A newly developed material composed of P(VDF-TrFE-CFE) terpolymer blended with 5% P(VDF-CTFE) electrostrictive actuators exhibits large strains (~5% at 150V/μm), fast actuation (>5 mm/s), and has a relatively high elastic modulus (1.2 GPa). This material exhibits more than double the elastic energy density and a 50% higher modulus of the original electrostrictive terpolymer. Hence, the potential for viable actuators in compact, full page Braille displays is greater than ever, provided actuators can be manufactured reliably in quantity. This talk presents recent work in scaling production of such rolled actuators. Actuators extend .5 mm, are confined to the 2.5 mm grid spacing of conventional Braille text, generate >0.5 N force and operate at less than 200V, thus meeting the primary requirements for a commercialized Braille display. To manufacture these actuators, cast films are stretched using a roll-to-roll zone drawing machine that is capable of producing quantities of 2 μm thick film with high quality. What follows is a discussion of this machine, the roll-to-roll film stretching process and an assessment of the resulting stretched film for use as linear strain actuators, like those used in our Braille cell.