The use of fabric reinforced overlays to control reflection cracking of composite pavements.

DOT National Transportation Integrated Search

1973-01-01

Fabric reinforcement was used in an attempt to prevent reflection cracking of two bituminous concrete layers overlying an 8-inch plain (unreinforced, unjointed) concrete base that was underlain by a portland cement stabilized subbase material. On the...

Pervious concrete physical characteristics and effectiveness in stormwater pollution reduction : tech transfer summaries.

DOT National Transportation Integrated Search

2016-04-01

Pervious concrete is an environmentally friendly and sustainable : material that allows rainfall to be drained and to percolate through : the concrete to the subbase/subgrade. Depending on the design of the : pervious concrete system, the pavement an...

User's guide: estimation of key PCC, base, subbase, and pavement engineering properties from routine tests and physical characteristics

DOT National Transportation Integrated Search

2012-08-01

Material characterization is a critical component of modern day pavement analysis, design, construction, quality : control/quality assurance, management, and rehabilitation. At each stage during the life of a project, the influence of : several funda...

Patients with Dry Eye Disease and Low Subbasal Nerve Density are at High Risk for an Accelerated Corneal Endothelial Cell Loss

PubMed Central

Kheirkhah, Ahmad; Satitpitakul, Vannarut; Hamrah, Pedram; Dana, Reza

2016-01-01

Purpose To evaluate the changes in corneal endothelial cell density (CECD) over time in patients with dry eye disease (DED) and to correlate the endothelial cell loss with corneal subbasal nerve density. Methods This retrospective study included 40 eyes of 20 patients with DED. Laser in vivo confocal microscopy had been performed in the central cornea of both eyes at an initial visit and repeated after a mean follow-up of 33.2 ± 10.2 months. The densities of corneal endothelial cells and subbasal nerves were measured in both visits and compared with 13 eyes of 13 normal age-matched controls. Results At the initial visit, the DED group had lower densities of corneal endothelial cells (2620 ± 386 cells/mm2) and subbasal nerves (17.8 ± 7.5 mm/mm2) compared with the control group (2861 ± 292 cells/mm2 and 22.8 ± 3.0 mm/mm2, with P=0.08 and P=0.01, respectively). At the end of follow-up, although there was no significant change in subbasal nerve density (16.7 ± 7.2 mm/mm2, P=0.43), the mean CECD significantly decreased to 2465 ± 391 cells/mm2 (P=0.01), with a mean corneal endothelial cell loss of 2.1 ± 3.6% per year. The endothelial cell loss showed a statistically significant negative correlation with the initial subbasal nerve density (Rs= −0.55, P=0.02). Conclusion Patients with DED have an accelerated corneal endothelial cell loss which is more than what has been reported in the literature for normal aging. Those with lower subbasal nerve density, in particular, are at a higher risk for endothelial cell loss over time. PMID:28060067

Finite element simulation of structural performance on flexible pavements with stabilized base/treated sub-base materials under accelerated loading : research project capsule.

DOT National Transportation Integrated Search

2008-12-01

PROBLEM: The full-scale accelerated pavement testing (APT) provides a unique tool for pavement : engineers to directly collect pavement performance and failure data under heavy : wheel loading. However, running a full-scale APT experiment is very exp...

Finite element simulation of structural performance on flexible pavements with stabilized base/treated subbase materials under accelerated loading : tech summary.

DOT National Transportation Integrated Search

2011-12-01

Accelerated pavement testing (APT) has been increasingly used by state highway agencies in recent years for evaluating pavement : design and performance through applying a simulative heavy vehicular load to the pavement section under controlled fi el...

Effect of fly ash on properties of crushed brick and reclaimed asphalt in pavement base/subbase applications.

PubMed

Mohammadinia, Alireza; Arulrajah, Arul; Horpibulsuk, Suksun; Chinkulkijniwat, Avirut

2017-01-05

Fly Ash (FA), an abundant by-product with no carbon footprint, is a potential stabilizer for enhancing the physical and geotechnical properties of pavement aggregates. In this research, FA was used in different ratios to stabilize crushed brick (CB) and reclaimed asphalt pavement (RAP) for pavement base/subbase applications. The FA stabilization of CB and RAP was targeted to improve the strength and durability of these recycled materials for pavement base/subbase applications. The Unconfined Compressive Strength (UCS) and resilient modulus (M R ) development of the stabilized CB and RAP aggregates was studied under room temperature and at an elevated temperatures of 40°C, and results compared with unbound CB and RAP. Analysis of atomic silica content showed that when the amount of silica and alumina crystalline was increased, the soil structure matrix deteriorated, resulting in strength reduction. The results of UCS and M R testing of FA stabilized CB and RAP aggregates indicated that FA was a viable binder for the stabilization of recycled CB and RAP. CB and RAP stabilized with 15% FA showed the highest UCS results at both room temperature and at 40°C. Higher temperature curing was also found to result in higher strengths. Copyright © 2016 Elsevier B.V. All rights reserved.

Partial Denervation of Subbasal Axons Persists Following Debridement Wounds to the Mouse Cornea

PubMed Central

Pajoohesh-Ganji, Ahdeah; Pal-Ghosh, Sonali; Tadvalkar, Gauri; Kyne, Briana M.; Saban, Daniel R.; Stepp, Mary Ann

2015-01-01

Although sensory reinnervation occurs after injury in the PNS, poor reinnervation in the elderly and those with diabetes often leads to pathology. Here we quantify subbasal axon density in the central and peripheral mouse cornea over time after three different types of injury. The mouse cornea is highly innervated with a dense array of subbasal nerves that form a spiral called the vortex at the corneal center or apex; these nerves are readily detected within flat mounted corneas. After anesthesia, corneal epithelial cells were removed using either a dulled blade or a rotating burr within an area demarcated centrally with a 1.5 mm trephine. A third wound type, superficial trephination, involved demarcating the area with the 1.5 mm trephine but not removing cells. By 7d after superficial trephination, subbasal axon density returns to control levels; by 28d the vortex reforms. Although axon density is similar to control 14d after dulled blade and rotating burr wounding, defects in axon morphology at the corneal apex remain. After 14d, axons retract from the center leaving the subbasal axon density reduced by 37.2% and 36.8% at 28d after dulled blade and rotating burr wounding, respectively, compared to control. Assessment of inflammation using flow cytometry shows that persistent inflammation is not a factor in the incomplete reinnervation. Expression of mRNAs encoding 22 regeneration associated genes (RAGs) involved in axon targeting assessed by QPCR reveals that netrin-1 and ephrin signaling are altered after wounding. Subpopulations of corneal epithelial basal cells at the corneal apex stop expressing ki67 as early as 7d after injury and by 14d and 28d after wounding, many of these basal cells undergo apoptosis and die. While subbasal axons are restored to their normal density and morphology after superficial trephination, subbasal axon recovery is partial after debridement wounds. The increase in corneal epithelial basal cell apoptosis at the apex observed at 14d after corneal debridement may destabilize newly reinnervated subbasal axons and lead to their retraction towards the periphery. PMID:26280222

Partial denervation of sub-basal axons persists following debridement wounds to the mouse cornea.

PubMed

Pajoohesh-Ganji, Ahdeah; Pal-Ghosh, Sonali; Tadvalkar, Gauri; Kyne, Briana M; Saban, Daniel R; Stepp, Mary Ann

2015-11-01

Although sensory reinnervation occurs after injury in the peripheral nervous system, poor reinnervation in the elderly and those with diabetes often leads to pathology. Here we quantify sub-basal axon density in the central and peripheral mouse cornea over time after three different types of injury. The mouse cornea is highly innervated with a dense array of sub-basal nerves that form a spiral called the vortex at the corneal center or apex; these nerves are readily detected within flat mounted corneas. After anesthesia, corneal epithelial cells were removed using either a dulled blade or a rotating burr within an area demarcated centrally with a 1.5 mm trephine. A third wound type, superficial trephination, involved demarcating the area with the 1.5 mm trephine but not removing cells. By 7 days after superficial trephination, sub-basal axon density returns to control levels; by 28 days the vortex reforms. Although axon density is similar to control 14 days after dulled blade and rotating burr wounding, defects in axon morphology at the corneal apex remain. After 14 days, axons retract from the center leaving the sub-basal axon density reduced by 37.2 and 36.8% at 28 days after dulled blade and rotating burr wounding, respectively, compared with control. Assessment of inflammation using flow cytometry shows that persistent inflammation is not a factor in the incomplete reinnervation. Expression of mRNAs encoding 22 regeneration-associated genes involved in axon targeting assessed by QPCR reveals that netrin-1 and ephrin signaling are altered after wounding. Subpopulations of corneal epithelial basal cells at the corneal apex stop expressing ki67 as early as 7 days after injury and by 14 and 28 days after wounding, many of these basal cells undergo apoptosis and die. Although sub-basal axons are restored to their normal density and morphology after superficial trephination, sub-basal axon recovery is partial after debridement wounds. The increase in corneal epithelial basal cell apoptosis at the apex observed at 14 days after corneal debridement may destabilize newly reinnervated sub-basal axons and lead to their retraction toward the periphery.

Leaching of different elements from subbase layers of alternative aggregates in pavement constructions.

PubMed

Flyhammar, P; Bendz, D

2006-09-01

The objective of this study was to analyze the accumulated effects of leaching in two test roads were municipal solid waste incineration (MSWI) bottom ash and aggregate from a railway embankment, respectively, were used as subbase aggregates. Solid samples from the subbase and the subgrade were collected in trenches, which were excavated perpendicular to the road extension. The samples were analyzed with respect to pH, water content, electrical conductivity and extractable fractions of macro and trace constituents. To conclude, spatial distribution patterns of different constituents in subbase and subgrade layers confirms the existence of two major transport processes in a road with permeable shoulders: diffusion underneath surface asphalt layers driven by a concentration gradient directed horizontally towards the shoulder of the road where the dissolved elements are carried away by advection.

Confocal Comparison of Corneal Reinnervation after Small Incision Lenticule Extraction (SMILE) and Femtosecond Laser In Situ Keratomileusis (FS-LASIK)

PubMed Central

Qin, Bing; Zhou, Zimei; Ni, Katherine; Le, Qihua; Xiang, Jun; Wei, Anji; Ma, Weiping; Zhou, Xingtao

2013-01-01

Purpose To evaluate corneal reinnervation, and the corresponding corneal sensitivity and keratocyte density after small incision lenticule extraction (SMILE) and femtosecond laser in situ keratomileusis (FS-LASIK). Methods In this prospective, non-randomized observational study, 18 patients (32 eyes) received SMILE surgery, and 22 patients (42 eyes) received FS-LASIK surgery to correct myopia. The corneal subbasal nerve density and microscopic morphological changes in corneal architecture were evaluated by confocal microscopy prior to surgery and at 1 week, 1 month, 3 months, and 6 months after surgery. A correlation analysis was performed between subbasal corneal nerve density and the corresponding keratocyte density and corneal sensitivity. Results The decrease in subbasal nerve density was less severe in SMILE-treated eyes than in FS-LASIK-treated eyes at 1 week (P = 0.0147), 1 month (P = 0.0243), and 3 months (P = 0.0498), but no difference was detected at the 6-month visit (P = 0.5277). The subbasal nerve density correlated positively with central corneal sensitivity in both groups (r = 0.416, P<0.0001, and r = 0.2567, P = 0.0038 for SMILE group and FS-LASIK group, respectively). The SMILE-treated eyes have a lower risk of developing peripheral empty space with epithelial cells filling in (P = 0.0005). Conclusions The decrease in subbasal nerve fiber density was less severe in the SMILE group than the FS-LASIK group in the first 3 months following the surgeries. The subbasal nerve density was correlated with central corneal sensitivity. PMID:24349069

Confocal comparison of corneal reinnervation after small incision lenticule extraction (SMILE) and femtosecond laser in situ keratomileusis (FS-LASIK).

PubMed

Li, Meiyan; Niu, Lingling; Qin, Bing; Zhou, Zimei; Ni, Katherine; Le, Qihua; Xiang, Jun; Wei, Anji; Ma, Weiping; Zhou, Xingtao

2013-01-01

To evaluate corneal reinnervation, and the corresponding corneal sensitivity and keratocyte density after small incision lenticule extraction (SMILE) and femtosecond laser in situ keratomileusis (FS-LASIK). In this prospective, non-randomized observational study, 18 patients (32 eyes) received SMILE surgery, and 22 patients (42 eyes) received FS-LASIK surgery to correct myopia. The corneal subbasal nerve density and microscopic morphological changes in corneal architecture were evaluated by confocal microscopy prior to surgery and at 1 week, 1 month, 3 months, and 6 months after surgery. A correlation analysis was performed between subbasal corneal nerve density and the corresponding keratocyte density and corneal sensitivity. The decrease in subbasal nerve density was less severe in SMILE-treated eyes than in FS-LASIK-treated eyes at 1 week (P = 0.0147), 1 month (P = 0.0243), and 3 months (P = 0.0498), but no difference was detected at the 6-month visit (P = 0.5277). The subbasal nerve density correlated positively with central corneal sensitivity in both groups (r = 0.416, P<0.0001, and r = 0.2567, P = 0.0038 for SMILE group and FS-LASIK group, respectively). The SMILE-treated eyes have a lower risk of developing peripheral empty space with epithelial cells filling in (P = 0.0005). The decrease in subbasal nerve fiber density was less severe in the SMILE group than the FS-LASIK group in the first 3 months following the surgeries. The subbasal nerve density was correlated with central corneal sensitivity.

Early corneal nerve damage and recovery following small incision lenticule extraction (SMILE) and laser in situ keratomileusis (LASIK).

PubMed

Mohamed-Noriega, Karim; Riau, Andri K; Lwin, Nyein C; Chaurasia, Shyam S; Tan, Donald T; Mehta, Jodhbir S

2014-03-25

We compared early corneal nerve changes after small incision lenticule extraction (SMILE) and laser in situ keratomileusis (LASIK). A total of 12 rabbits underwent LASIK in one eye and SMILE in the fellow eye. Baseline and follow-up evaluations at 1, 2, and 4 weeks postoperatively were performed with in vivo confocal microscopy to evaluate 5 different areas within the treated zone: center, superior, inferior, nasal, and temporal. Cryosections of the corneas and whole mount of the extracted SMILE lenticules were analyzed with immunostaining of βIII-tubulin. One week after SMILE and LASIK, a decrease in nerve length and density was observed in all evaluated areas. A trend toward greater subbasal nerve length and density (SLD), more eyes with subbasal nerves (ESN), more eyes with subbasal nerves longer than 200 μm (SNL), and higher mean number of subbasal nerves by frame (NSN) in SMILE than in LASIK groups was observed at subsequent follow-up time points. Only the SMILE group showed a recovery of SLD, ESN, and NSN by week 4 (P > 0.05). A trend toward more eyes with sprouting subbasal nerves and greater mean number of sprouting nerves was observed in LASIK than in SMILE, indicating that more subbasal nerves were disrupted and undergoing regeneration after LASIK. Immunostaining at postoperative week 4 revealed a faster stromal nerve recovery in post-SMILE eyes compared to post-LASIK eyes. Our findings suggest that SMILE results in less nerve damage and faster nerve recovery than LASIK.

Implementation of curing, texturing, subbase, and compaction measurement alternatives for continuously reinforced concrete pavement.

DOT National Transportation Integrated Search

2014-04-01

This report evaluates four different subbase types, two different concrete mix designs (a standard Texas : Department of Transportation gradation and an optimized gradation), three different curing compounds, and : four different surface textures tha...

Subbase and subgrade performance investigation for concrete pavement.

DOT National Transportation Integrated Search

2009-05-01

Recently, TxDOT has become increasingly aware of the rising cost associated with the use of asphalt : concrete bond breakers to meet the FHWA requirement of using a permanently stabilized, nonerodable : subbase layer below the concrete slab. The main...

Recycled Coarse Aggregate Produced by Pulsed Discharge in Water

NASA Astrophysics Data System (ADS)

Namihira, Takao; Shigeishi, Mitsuhiro; Nakashima, Kazuyuki; Murakami, Akira; Kuroki, Kaori; Kiyan, Tsuyoshi; Tomoda, Yuichi; Sakugawa, Takashi; Katsuki, Sunao; Akiyama, Hidenori; Ohtsu, Masayasu

In Japan, the recycling ratio of concrete scraps has been kept over 98 % after the Law for the Recycling of Construction Materials was enforced in 2000. In the present, most of concrete scraps were recycled as the Lower Subbase Course Material. On the other hand, it is predicted to be difficult to keep this higher recycling ratio in the near future because concrete scraps increase rapidly and would reach to over 3 times of present situation in 2010. In addition, the demand of concrete scraps as the Lower Subbase Course Material has been decreased. Therefore, new way to reuse concrete scraps must be developed. Concrete scraps normally consist of 70 % of coarse aggregate, 19 % of water and 11 % of cement. To obtain the higher recycling ratio, the higher recycling ratio of coarse aggregate is desired. In this paper, a new method for recycling coarse aggregate from concrete scraps has been developed and demonstrated. The system includes a Marx generator and a point to hemisphere mesh electrode immersed in water. In the demonstration, the test piece of concrete scrap was located between the electrodes and was treated by the pulsed discharge. After discharge treatment of test piece, the recycling coarse aggregates were evaluated under JIS and TS and had enough quality for utilization as the coarse aggregate.

Frost Susceptibility of Soil, Review of Index Tests,

DTIC Science & Technology

1981-12-01

contained in the CAA ( 1948 ) speci- used for both subgrade and base/subbase materi- fications for the construction of airports. Ac- als. An additional...Texas. Details of the Texas method for deter- t Percentage of portion smaller than mining FS were reported by Carothers ( 1948 ) and 20mm were taken...material. pies are frozen from the bottom up at a constant rate of heat flow, similar to the method sug- Switzerland gested by Penner and Ueda (1978

Optimizing pavement base, subbase, and subgrade layers for cost and performance of local roads : [tech transfer summary].

DOT National Transportation Integrated Search

2014-12-01

It is common for local street and road pavements to be constructed using : portland cement concrete (PCC) directly supported on natural subgrade : without considering subgrade treatment or structural support layers such : as granular subbase. In orde...

A case study : early cracking of unreinforced concrete pavement.

DOT National Transportation Integrated Search

1973-01-01

A study of cores from both the concrete and subbase of the cracked pavement, along with an examination of the in-place subgrade and subbase, suggested that there was no structural damage to the pavement except for the cracking. The situation was aggr...

[Quantitative analysis of the corneal subbasal nerves in different degrees of dry eye with AutoCAD].

PubMed

Cheng, Y; Wu, J; Zhu, H F; Cheng, Y; Zhu, X P

2016-03-01

To evaluate the practical value of AutoCAD in quantitative analysis of corneal subbasal epithelial nerves with different degrees of dry eye. Ninety patients were divided into groups of mild, moderate, and severe dry eye, 30 patients (60 eyes) in each group. And 30 healthy volunteers were recruited as the normal control group. Confocal microscopy was used to observe the length of the subbasal epithelial nerve plexus. The images were analyzed by AutoCAD software to determine the density (mm/mm(2)), the number of branches, and the curvature score of the subbasal epithelial nerves. These data of patients with dry eye and the controls were statistically compared, by analysis of variance(ANOV). By AutoCAD software, quantitative analysis of the corneal subbasal epithelial nerves was successfully performed. The nerve density in the patients with mild dry eye[(16.70±3.43) mm/mm(2)] was not significantly different from the controls[(15.87 ± 2.75) mm/mm(2)] (P=0.880), but the number of nerval branches 13.43±2.46 and the curvature 3.10±0.80 increased significantly (P<0.001). The nerve density in the patients with moderate and severe dry eye was significantly different from that in the normal control group (F=114.739, P<0.001). The neural density was significantly lower in the patients with severe dry eye than the controls, but there was no significant difference in the curvature scores between the two groups (P= 0.557). AutoCAD software is useful in the quantitative analysis of corneal nerve images under a confocal microscope. The corneal subbasal epithelial nerve density, the number of branches, and the curvature of the nerves are related to the degree of dry eye, and may be used as clinical indicators.

Pilot-scale road subbase made with granular material formulated with MSWI bottom ash and stabilized APC fly ash: environmental impact assessment.

PubMed

del Valle-Zermeño, R; Formosa, J; Prieto, M; Nadal, R; Niubó, M; Chimenos, J M

2014-02-15

A granular material (GM) to be used as road sub-base was formulated using 80% of weathered bottom ash (WBA) and 20% of mortar. The mortar was prepared separately and consisted in 50% APC and 50% of Portland cement. A pilot-scale study was carried on by constructing three roads in order to environmentally evaluate the performance of GM in a real scenario. By comparing the field results with those of the column experiments, the overestimations observed at laboratory scale can be explained by the potential mechanisms in which water enters into the road body and the pH of the media. An exception was observed in the case of Cu, whose concentration release at the test road was higher. The long-time of exposure at atmospheric conditions might have favoured oxidation of organic matter and therefore the leaching of this element. The results obtained showed that immobilization of all heavy metals and metalloids from APC is achieved by the pozzolanic effect of the cement mortar. This is, to the knowledge of the authors, the only pilot scale study that is considering reutilization of APC as a safe way to disposal. Copyright © 2013 Elsevier B.V. All rights reserved.

LPT. Shield test facility (TAN645 and 646). Basement and subbasement ...

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

LPT. Shield test facility (TAN-645 and -646). Basement and sub-basement plan. Stairway plans and details. Ralph M. Parsons 1229-17 ANP/GE-6-645-A-2. April 1957. Approved by INEEL Classification Office for public release. INEEL index code no. 037-0645/0646-00-693-107348 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

Design Constructibility Reviews.

DTIC Science & Technology

1987-01-01

specifications for base and sub-base courses, and wearing course.I Item 21 - Has provision been made in the specifications for positive control of the temperature...of the bituminous material? Item 22 - Test results on samples of asphalt , aggregate, sand and mix should be obtained from the plant prior to placing...in the * drawings. Item 3 - Make sure that stud types, sizes and pacinqs are spelled out in the plans and sc-i catr-. Item 4 - All welders that will

Discharge characteristics of four highway drainage systems in Ohio

USGS Publications Warehouse

Straub, D.E.

1995-01-01

Excessive water in the subbase of high-way combined with large traffic volumes and heavy loads is a major cause of road deterioration. Prompt removal of any excess water in a subbase will decrease the road deterioration and extend the effective life of a highway. This study presents discharge characteristics of four highway subbase drainage systems. These systems consisted of shallow, longitudal trenches with geocomposite drain materials (edge drains made from a polyethylene core surrounded by a geotextile filter fabric) that underline the joint between the shoulder and the traffic lane of State Route 16, approximately 1.0 mile southeast of Granville, Ohio. For selected rainfall-runoff events the maximum discharge, discharge characteristics from April 1991 through November 1993 were computed for three geocomposite products- a post type, an oblong-pipe type, and a cusp type-and a conventional perforated pipe edge drain. In general, the discharge characteristics of the conventional edge drain and that of the oblong-pipe edge drain were similar for most of the rainfall-runoff event characteristics. Both produced most of the highest maximum discharges and largest discharge volumes among the four longitudal edge drains. The post edge drain produced smaller maximum discharge and volumes than the conventional and oblong-pipe edge drains, but it had the shortest lag times for most of the event characteristics. The cusp edge drain produced small maximum discharges and small volumes similar to those from the post edge drain, but it had the longest lag times of all the edge drains for most of the event characteristics. The cusp edge drain may have also had some problems during installation which could have affected the discharge characteristics.

Long-term leaching from recycled concrete aggregates applied as sub-base material in road construction.

PubMed

Engelsen, Christian J; van der Sloot, Hans A; Petkovic, Gordana

2017-06-01

In the present study, the metal leaching from recycled concrete aggregates (RCA) used in road sub-base is presented after >10years of exposure. The released levels of inorganic constituents, the effect of small variation of pH and the use of de-icing salt during winter season were studied. In addition, speciation modelling for the major elements has been provided. The pH varied from 7.5 to 8.5 for the sub-base constructed with RCA whereas the pH of around 8 was obtained for the test section not affected by the traffic and de-icing salts. Despite a small variation in pH, the leachability of Al, Ca and Mg was found to be strongly dependent on pH and fair agreement between the measured and predicted concentrations was obtained. The speciation modelling indicated that gibbsite, calcite and magnesite controlled the solubility of Al, Ca and Mg, respectively, which was in agreement with the expected carbonation products. Due to the larger pH fluctuations in the test sections exposed to the road traffic, increased concentrations were observed for the oxyanions. The same effect was not seen for the trace metal cations Cd, Cu, Ni, Pb and Zn. The distinct pH dependent leaching profile (solubility maximum in the mildly basic pH region) for vanadium could be seen after 10years of exposure. The simplified risk assessment showed that the released quantities did not exceed the chosen acceptance criteria for groundwater and fresh water. The results obtained for the test section not influenced by road dust and de-icing salts, complied with these criteria even without considering any dilution effects caused by the mixing of pore water with groundwater. Copyright © 2017 Elsevier B.V. All rights reserved.

Development of an evaporation-optimized and water-permeable pavement

NASA Astrophysics Data System (ADS)

Starke, P.; Göbel, P.; Coldewey, W. G.

2009-04-01

During recent decades, urban areas have been threatened more frequently by flood events. Furthermore, the potential for damage from these events has increased on average. The construction of houses, streets and parking lots has caused this trend by sealing the ground surface, i.e. these water-impermeable areas reduce the natural infiltration and evaporation-rates, and in some cases it is even completely stopped. The consequence is the so called "urban water cycle". Water from precipitation cannot be stored anywhere and so there is an immediate and very high surface run-off effect. Especially after intense rain events, canalisations and sewage-treatment plants are overloaded and this leads to higher costs for water treatment and to environmental damage. A practical solution to this problem is the use of water-permeable pavements. Here higher infiltration rates lead to a groundwater recharge that is greater than that of natural soils. The consequences from using these surfaces are already noticeable in many places through increasing groundwater levels. These increases cause damage to buildings. A second difference from a natural-soil water-balance is a lower evapotranspiration rate. Up to now the evaporation rates for water-permeable pavements has not been established accurately. The aim of the applied research project at the University of Muenster, which is sponsored by the DBU (The German Federal Environmental Foundation), is to gain knowledge of urban evaporation rates and of water-permeable surfaces, especially water-permeable pavements. Water-permeable pavements consist of the paving stone surface and the two sub-base layers below. Pre-investigations show that evaporation can be influenced by the complete sub-base. Therefore, the first step was to investigate which materials are used for sub-base construction. All in all, 27 materials were collected from throughout Germany and these materials were then tested (in terms of physical and hydraulic attributes) in the soil-mechanics laboratory of the University of Muenster. For their street construction useability, and having regard to evaporation, a selection of appropriate materials were built into a test field. The test field consisted of seven hexagonal areas each about 10 m2 large, which are placed in a honeycomb manner. The evaporation measurements are carried out with a WERNER tunnel-evaporation gauge (TUV) which is able to detect the actual evaporation rate. Its functional principle also allows a direct comparison between the middle reference area and one outer area of the test field. Every measuring period lasts one week and after that the TUV is moved to between the next outer area and the reference area. So the TUV rotates over the whole test field and every measuring area is covered by a measurement. In addition, a Hellman rain-gauge near the test field enables the measurement of a direct precipitation-evaporation ratio. Since the start of the measurements in July 2008, the first results collected showed that measureable differences in evaporation rates could be detected after a few measuring periods, i.e. the differences are up to 32% between the reference area and one outer area. In July 2009, the six outer measuring areas of the test field will be replaced and, based on the actual results collected, the sub-base layers will be replaced by an evaporation-optimized sub-base. The new outer measuring areas will only differ in terms of a different paving-stone surface. These paving stones are actually under developement and under laboratory testing (i.e. permeability, porosity, capillary water and evaporationrates), and so they will be evaporation-opimized. The open-air test in the test field is to assure and compare the evaporation rates. As a final result, the evaporation-optimized and water-permeable pavement and the knowledge of its exact drainage ratio will allow city planners or architects to build water-permeable streets with due regard to the respective area-specific conditions. This new developed pavement is an approximation to the water balance of a natural soil. In this way, the danger of flooding can be further reduced in urban areas.

Rapid, automated mosaicking of the human corneal subbasal nerve plexus.

PubMed

Vaishnav, Yash J; Rucker, Stuart A; Saharia, Keshav; McNamara, Nancy A

2017-11-27

Corneal confocal microscopy (CCM) is an in vivo technique used to study corneal nerve morphology. The largest proportion of nerves innervating the cornea lie within the subbasal nerve plexus, where their morphology is altered by refractive surgery, diabetes and dry eye. The main limitations to clinical use of CCM as a diagnostic tool are the small field of view of CCM images and the lengthy time needed to quantify nerves in collected images. Here, we present a novel, rapid, fully automated technique to mosaic individual CCM images into wide-field maps of corneal nerves. We implemented an OpenCV image stitcher that accounts for corneal deformation and uses feature detection to stitch CCM images into a montage. The method takes 3-5 min to process and stitch 40-100 frames on an Amazon EC2 Micro instance. The speed, automation and ease of use conferred by this technique is the first step toward point of care evaluation of wide-field subbasal plexus (SBP) maps in a clinical setting.

Stormwater infiltration and surface runoff pollution reduction performance of permeable pavement layers.

PubMed

Niu, Zhi-Guang; Lv, Zhi-Wei; Zhang, Ying; Cui, Zhen-Zhen

2016-02-01

In this paper, the laboratory-scale permeable pavement layers, including a surface permeable brick layer, coarse sand bedding layers (thicknesses = 2, 3.5, and 5 cm), and single-graded gravel sub-base layers (thicknesses = 15, 20, 25, and 30 cm), were built to evaluate stormwater infiltration and surface runoff pollution reduction performance. And, the infiltration rate (I) and concentrations of suspended solids (SS), total phosphorus (TP), chemical oxygen demand (COD), ammonia nitrogen, and total nitrogen (TN) were measured under the simulated rainfall intensity of 72.4 mm/h over duration of 60 min. The results indicate that the thickness factor primarily influences the infiltration rate and pollutant removal rate. The highest steady infiltration rate was for surface brick layer 51.0 mm/h, for 5-cm sand bedding layer 32.3 mm/h, and for 30-cm gravel sub-base layer 42.3 mm/h, respectively. The SS average removal rate was relative higher (79.8 ∼ 98.6 %) for all layers due to the interception and filtration. The average removal rates of TP and COD were for surface layer 71.2 and 24.1 %, for 5-cm bedding layer 54.8 and 9.0 %, and for 20-cm sub-base layer 72.2 and 26.1 %. Ammonia nitrogen and TN cannot steadily be removed by layers according to the experiment results. The optimal thickness of bedding sands was 5 cm, and that of sub-base gravels was 20 ∼ 30 cm.

APC fly ashes stabilized with Portland cement for further development of road sub-base aggregates

NASA Astrophysics Data System (ADS)

Formosa, J.; Giro-Paloma, J.; Maldonado-Alameda, A.; Huete-Hernández, S.; Chimenos, J. M.

2017-10-01

Although waste-to-energy plants allow reducing the mass and volume of municipal solid waste (MSW) incinerated, an average around 30 % of the total content remains as bottom ash (BA) and air pollution control (APC) ashes at the end of combustion process. While weathered bottom ash (WBA) is considered a non-hazardous residue that can be revalorized as a secondary aggregate, APC fly ashes generated during the flue gas treatment are classified as hazardous waste and are handled in landfill disposal after stabilization, usually with Portland cement (OPC). However, taking into account the amount of APC residues produced and the disposing cost in landfill, their revalorization is an important issue that could be effectively addressed. As MSW can be incinerated producing bottom ashes (BA) or air pollutant control (APC) residues, the development of a mortar formulated with APC fly ash as secondary building material is a significant risk to the environment for their content of heavy metals. In this way, Design of Experiment (DoE) was used for the improvement of granular material (GM) formulation composed by APC and OPC for further uses as road sub-base aggregate. DoE analysis was successful in the modelling and optimization the formulation as function of the mechanical properties and APC amount. Consequently, an optimal mortar formulation (OMF) of around 50 wt.% APC and 50 wt.% OPC was considered. The OMF leachates and abrasion resistance have been analyzed. These results have demonstrated the viability of OMF as non-hazardous material feasible to be used as secondary aggregate. Moreover, it would be possible to consider the environmental assessment of a GM composed by ≈20 wt.% of OMF and ≈80 wt.% of WBA in order to improve mechanical properties and heavy metals stabilization.

Effects on evaporation rates from different water-permeable pavement designs.

PubMed

Starke, P; Göbel, P; Coldewey, W G

2011-01-01

The urban water balance can be attenuated to the natural by water-permeable pavements (WPPs). Furthermore, WPPs have a 16% higher evaporation rate than impermeable pavements, which can lead to a better urban climate. Evaporation rates from pavements are influenced by the pavement surface and by the deeper layers. By a compared evaporation measurement between different WPP designs, the grain size distribution of the sub-base shows no influence on the evaporation rates in a significant way. On the contrary, a sub-base made of a twin-layer decreases the evaporation by 16% compared to a homogeneous sub-base. By a change in the colour of the paving stone, 19% higher evaporation rates could be achieved. A further comparison shows that the transpiration-effect of the grass in grass pavers increases the evaporation rates more than threefold to pervious concrete pavements. These high evapotranspiration rates can not be achieved with a pervious concrete paving stone. In spite of this, the broad field of application of the pervious concrete paving stone increases the importance in regard to the urban climate.

Strength and deformation characteristics of pavements

NASA Astrophysics Data System (ADS)

Shook, J. F.; Kallas, B. F.; McCullough, B. F.; Taute, A.; Rada, G.; Witczak, M. W.; Heisey, J. S.; Stokoe, K. H.; Meyer, A. H.; Huffman, M. S.

The Colorado experimental base project was a full-scale field experment constructed with various thicknesses of two full depth hot mix sand asphalt beans, one full depth asphalt concrete base, and one thickness of a standard design with untreated base and subbase layers. Relative thicknesses of one asphalt concrete base, two hot mix sand asphalt bases, and one standard design with untreated base and subbase required to give an equal level of pavement performance were determined. Certain measured properties of the pavement and the pavement components were related to observed levels of performance by using both empirical and theoretical models for pavement behavior.

A risk-based approach for assessing the recycling potential of an alkaline waste material as road sub-base filler material.

PubMed

Di Gianfilippo, Martina; Verginelli, Iason; Costa, Giulia; Spagnuolo, Riccardo; Gavasci, Renato; Lombardi, Francesco

2018-01-01

In this work we present an integrated risk-based approach that can be used to evaluate the recycling potential of an alkaline waste material such as incineration bottom ash (BA) as unbound material for road sub-base construction. This approach, which is aimed at assessing potential risks to the groundwater resource (in terms of drinking water quality) and human health associated to the leaching of contaminants from the BA, couples the results of leaching tests for the estimation of source concentrations with the fate and transport models usually adopted in risk assessment procedures. The effects of weathering and of the type of leaching test employed to evaluate eluate concentrations were assessed by carrying out different simulations using the results of laboratory leaching tests. Specifically, pH-dependence and column percolation leaching tests were performed on freshly collected and 1-year naturally weathered BA samples produced from a grate-fired incineration plant treating Refuse Derived Fuel (RDF). To evaluate a broad span of possible scenario conditions, a Monte Carlo analysis was performed running 5000 simulations, randomly varying the input parameters within the ranges expected in the field. In nearly all the simulated conditions, the concentrations of contaminants in the groundwater for the specific type of BA tested in this work were well below EU and WHO drinking water quality criteria. Nevertheless, some caution should be paid in the case of the establishment of acidic conditions in the field since in this case the concentration of some elements (i.e. Al, Pb and Zn) is expected to exceed threshold values. In terms of risks to human health, for the considered utilization scenario the probability of exceeding the acceptable reference dose for water ingestion was usually less than 1% (except for Cr and Pb for which the probability was lower than 3.5% and 7%, respectively). Copyright © 2017 Elsevier Ltd. All rights reserved.

Local Variability of Parameters for Characterization of the Corneal Subbasal Nerve Plexus.

PubMed

Winter, Karsten; Scheibe, Patrick; Köhler, Bernd; Allgeier, Stephan; Guthoff, Rudolf F; Stachs, Oliver

2016-01-01

The corneal subbasal nerve plexus (SNP) offers high potential for early diagnosis of diabetic peripheral neuropathy. Changes in subbasal nerve fibers can be assessed in vivo by confocal laser scanning microscopy (CLSM) and quantified using specific parameters. While current study results agree regarding parameter tendency, there are considerable differences in terms of absolute values. The present study set out to identify factors that might account for this high parameter variability. In three healthy subjects, we used a novel method of software-based large-scale reconstruction that provided SNP images of the central cornea, decomposed the image areas into all possible image sections corresponding to the size of a single conventional CLSM image (0.16 mm2), and calculated a set of parameters for each image section. In order to carry out a large number of virtual examinations within the reconstructed image areas, an extensive simulation procedure (10,000 runs per image) was implemented. The three analyzed images ranged in size from 3.75 mm2 to 4.27 mm2. The spatial configuration of the subbasal nerve fiber networks varied greatly across the cornea and thus caused heavily location-dependent results as well as wide value ranges for the parameters assessed. Distributions of SNP parameter values varied greatly between the three images and showed significant differences between all images for every parameter calculated (p < 0.001 in each case). The relatively small size of the conventionally evaluated SNP area is a contributory factor in high SNP parameter variability. Averaging of parameter values based on multiple CLSM frames does not necessarily result in good approximations of the respective reference values of the whole image area. This illustrates the potential for examiner bias when selecting SNP images in the central corneal area.

Influence of femtosecond lenticule extraction and small incision lenticule extraction on corneal nerve density and ocular surface: a 1-year prospective, confocal, microscopic study.

PubMed

Ishii, Rie; Shimizu, Kimiya; Igarashi, Akihito; Kobashi, Hidenaga; Kamiya, Kazutaka

2015-01-01

To compare the influence of femtosecond lenticule extraction (FLEx) and small incision lenticule extraction (SMILE) on corneal nerve density and the ocular surface for equivalent degrees of correction of myopia. Sixty eyes of 30 patients (8 males and 22 females, mean age: 31.0 ± 6.0 years) were included in the study. The patients underwent FLEx in 1 eye and SMILE in the other eye by random assignment. Subbasal nerve density was measured using confocal microscopy preoperatively and at 1 week, 1 and 3 months, and 1 year postoperatively. Ocular surface parameters such as Schirmer's test results, tear film break-up time, and corneal sensation were performed preoperatively and at 1 and 3 months postoperatively. In the FLEx group, subbasal nerve density was 18,390 ± 6,090 µm/mm(2) preoperatively and 5,770 ± 3,490 µm/mm(2) at 1 year postoperatively (P < .001, Dunnett's test). In the SMILE group, subbasal nerve density was 16,810 ± 6,220 µm/mm(2) preoperatively and 11,870 ± 8,200 µm/mm(2) at 1 year postoperatively (P = .21). The decrease in corneal nerve density was significantly less after SMILE than after FLEx at all postoperative visits (Mann-Whitney U test, P < .05). FLEx resulted in a significant decrease in Schirmer's test results, tear film break-up time, and corneal sensation at all postoperative visits, whereas SMILE induced no significant changes in these parameters (P > .05). There was less damage to the sub-basal nerve plexus of the cornea and less effect on the ocular surface parameters after SMILE than after FLEx. Copyright 2015, SLACK Incorporated.

Femtosecond laser cutting of human corneas for the subbasal nerve plexus evaluation.

PubMed

Kowtharapu, B S; Marfurt, C; Hovakimyan, M; Will, F; Richter, H; Wree, A; Stachs, O; Guthoff, R F

2017-01-01

Assessment of various morphological parameters of the corneal subbasal nerve plexus is a valuable method of documenting the structural and presumably functional integrity of the corneal innervation in health and disease. The aim of this work is to establish a rapid, reliable and reproducible method for visualization of the human corneal SBP using femtosecond laser cut corneal tissue sections. Trephined healthy corneal buttons were fixed and processed using TissueSurgeon-a femtosecond laser based microtome, to obtain thick tissue sections of the corneal epithelium and anterior stroma cut parallel to the ocular surface within approximately 15 min. A near infrared femtosecond laser was focused on to the cornea approximately 70-90 μm from the anterior surface to induce material separation using TissueSurgeon. The obtained corneal sections were stained following standard immunohistochemical procedures with anti-neuronal β-III tubulin antibody for visualization of the corneal nerves. Sections that contained the epithelium and approximately 20-30 μm of anterior stroma yielded excellent visualisation of the SBP with minimal optical interference from underlying stromal nerves. In conclusion, the results of this study have demonstrated that femtosecond laser cutting of the human cornea offers greater speed, ease and reliability than standard tissue preparation methods for obtaining high quality thick sections of the anterior cornea cut parallel to the ocular surface. © 2016 The Authors Journal of Microscopy © 2016 Royal Microscopical Society.

Influence of the Mechanical Properties of Third-Generation Artificial Turf Systems on Soccer Players’ Physiological and Physical Performance and Their Perceptions

PubMed Central

Sánchez-Sánchez, Javier; García-Unanue, Jorge; Jiménez-Reyes, Pedro; Gallardo, Ana; Burillo, Pablo; Felipe, José Luis; Gallardo, Leonor

2014-01-01

The aim of this research was to evaluate the influence of the mechanical properties of artificial turf systems on soccer players’ performance. A battery of perceptive physiological and physical tests were developed on four different structural systems of artificial turf (System 1: Compacted gravel sub-base without elastic layer; System 2: Compacted gravel sub-base with elastic layer; System 3: Asphalt sub-base without elastic layer; System 4: Asphalt sub-base with elastic layer). The sample was composed of 18 soccer players (22.44±1.72 years) who typically train and compete on artificial turf. The artificial turf system with less rotational traction (S3) showed higher total time in the Repeated Sprint Ability test in comparison to the systems with intermediate values (49.46±1.75 s vs 47.55±1.82 s (S1) and 47.85±1.59 s (S2); p<0.001). The performance in jumping tests (countermovement jump and squat jump) and ball kicking to goal decreased after the RSA test in all surfaces assessed (p<0.05), since the artificial turf system did not affect performance deterioration (p>0.05). The physiological load was similar in all four artificial turf systems. However, players felt more comfortable on the harder and more rigid system (S4; visual analogue scale = 70.83±14.28) than on the softer artificial turf system (S2; visual analogue scale = 54.24±19.63). The lineal regression analysis revealed a significant influence of the mechanical properties of the surface of 16.5%, 15.8% and 7.1% on the mean time of the sprint, the best sprint time and the maximum mean speed in the RSA test respectively. Results suggest a mechanical heterogeneity between the systems of artificial turf which generate differences in the physical performance and in the soccer players’ perceptions. PMID:25354188

Long term safety and tolerability of Tafluprost 0.0015% vs Timolol 0.1% preservative-free in ocular hypertensive and in primary open-angle glaucoma patients: a cross sectional study.

PubMed

Rolle, Teresa; Spinetta, Roberta; Nuzzi, Raffaele

2017-08-03

The effects of preservatives of antiglaucoma medications on corneal surface and tear function have been widely shown in literature; it's not the same as regards the active compounds themselves. The purpose of our study was to compare Ocular Surface Disease (OSD) signs and symptoms of Tafluprost 0.0015% versus preservative free (PF) Timolol 0.1% eyedrops in ocular hypertensive (OH) and in primary open-angle glaucoma (POAG) patients. A cross-sectional study included patients in monotherapy for at least 36 months with Tafluprost 0.0015% (27) or PF Timolol 0.1% (24) and 20 healthy age and sex-matched volunteers. All subjects underwent clinical tests (Schirmer I and break-up time), in vivo confocal microscopy (IVCM) and were surveyed using Ocular Surface Disease Index (OSDI) and Glaucoma Symptoms Scale (GSS) questionnaires. The groups were compared with ANOVA, Kruskal-Wallis test, t-test, Mann-Whitney test and Bonferroni's adjustment of p-values. No significant differences were found in questionnaires scores, clinical tests, IVCM variables between therapy groups. Tafluprost 0.0015% group showed significantly higher OSDI score, basal epithelial cells density, stromal reflectivity, sub-basal nerves tortuosity (p = 0.0000, 0.037, 0.006, 0.0000) and less GSS score, number of sub-basal nerves (p = 0.0000, 0.037) than controls but similar clinical tests results (p > 0.05). PF Timolol group had significantly higher OSDI score, basal epithelial cells density, stromal reflectivity and sub-basal nerve tortuosity (p = 0.000, 0.014, 0.008, 0.002), less GSS score, BUT and number of sub-basal nerves (p = 0.0000, 0.026, 0.003) than controls. Compared to PF Timolol 0.1%, Tafluprost 0.0015% showed similar safety with regards to tear function and corneal status and a similar tolerability profile. Both therapy groups show some alterations in corneal microstructure but no side effects on tear function except for an increased tear instability in PF Timolol 0.1% group. Ophtalmologists should be aware that even PF formulations may lead to a mild ocular surface impairment.

Deformation Behavior of Recycled Concrete Aggregate during Cyclic and Dynamic Loading Laboratory Tests

PubMed Central

Sas, Wojciech; Głuchowski, Andrzej; Gabryś, Katarzyna; Soból, Emil; Szymański, Alojzy

2016-01-01

Recycled concrete aggregate (RCA) is a relatively new construction material, whose applications can replace natural aggregates. To do so, extensive studies on its mechanical behavior and deformation characteristics are still necessary. RCA is currently used as a subbase material in the construction of roads, which are subject to high settlements due to traffic loading. The deformation characteristics of RCA must, therefore, be established to find the possible fatigue and damage behavior for this new material. In this article, a series of triaxial cyclic loading and resonant column tests is used to characterize fatigue in RCA as a function of applied deviator stress after long-term cyclic loading. A description of the shakedown phenomenon occurring in the RCA and calculations of its resilient modulus (Mr) as a function of fatigue are also presented. Test result analysis with the stress-life method on the Wohler S-N diagram shows the RCA behavior in accordance with the Basquin law. PMID:28773905

Bowman Break and Subbasal Nerve Plexus Changes in a Patient With Dry Eye Presenting With Chronic Ocular Pain and Vitamin D Deficiency.

PubMed

Shetty, Rohit; Deshpande, Kalyani; Deshmukh, Rashmi; Jayadev, Chaitra; Shroff, Rushad

2016-05-01

To report the case of a 40-year-old patient with persistent bilateral ocular pain and discomfort for 2 years in whom conventional management of dry eye had failed. Detailed ocular examination, meibography, and tear film evaluation were suggestive of bilateral meibomian gland dysfunction and evaporative dry eye. Topical medication failed to alleviate the patient's symptoms. To identify the cause of pain, imaging was performed with in vivo confocal microscopy and anterior segment spectral domain optical coherence tomography. Systemic evaluation revealed severe vitamin D deficiency with a value of 5.86 ng/mL. Case report. In vivo confocal microscopy showed abnormal subbasal nerve plexus morphology, increased dendritic cell density, and enlarged terminal nerve sprouts. A breach in the Bowman layer was detected in both eyes on spectral domain optical coherence tomography. Conventional management having failed, LipiFlow treatment (TearScience, Morrisville, NC) was performed and topical therapy with cyclosporine 0.05%, steroids, and lubricating eye drops was initiated with incomplete symptomatic relief. However, with parenteral therapy for vitamin D deficiency, there was a dramatic improvement in the patient's symptoms. Inflammation aggravated by vitamin D deficiency results in an altered epithelial profile, Bowman layer damage, recruitment of dendritic cells, and altered subbasal nerve plexus features in patients with chronic dry eye disease. These can serve as potential imaging markers for studying the underlying mechanisms in patients with dry eye disease with persisting symptoms despite aggressive conventional treatment.

Accelerated loading evaluation of subbase layers in pavement performance.

DOT National Transportation Integrated Search

2010-04-01

This report documents the research efforts conducted at the Louisiana Transportation Research Center (LTRC) regarding chemical stabilization of the naturally wet and problematic clayey soils typically found as subgrade in south Louisiana and provides...

VIEW OF TWO HEAVY WATER STORAGE TANKS (BEHIND SUPPORT COLUMNS ...

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

VIEW OF TWO HEAVY WATER STORAGE TANKS (BEHIND SUPPORT COLUMNS AND STEEL BEAMS), SUB-BASEMENT LEVEL -27’, LOOKING SOUTHWEST - Physics Assembly Laboratory, Area A/M, Savannah River Site, Aiken, Aiken County, SC

Cold in-place recycled bituminous pavement Dorset-Danby, VT.

DOT National Transportation Integrated Search

2015-01-01

The report documents the long-term performance and cost effectiveness of four rehabilitation : treatments in a mostly homogenous environment. The underlying subbase and subgrade soils, traffic : volume, existing pavement structure and ambient conditi...

Soil stabilization field trial : interim report II.

DOT National Transportation Integrated Search

2002-02-01

Shrinkage cracks in cement-stabilized bases/subbase can be alleviated by specifying the right cement dosage, or by other additives/procedures that suppress crack susceptibility. A field trial of six 1000 ft sections to investigate several alternative...

Soil stabilization field trial : interim report.

DOT National Transportation Integrated Search

2001-04-01

Shrinkage cracks in cement-stabilized bases/subbase can be alleviated by specifying : the right cement dosage, or by other additives/procedures that suppress crack susceptibility. A field : trial of six 1000 ft test sections to investigate several al...

Soil stabilization field trial : interim report I.

DOT National Transportation Integrated Search

2001-04-01

Shrinkage cracks in cement-stabilized bases/subbase can be alleviated by specifying the right cement dosage, or by other additives/procedures that suppress crack susceptibility. A field trial of six 1000 ft test sections to investigate several altern...

Soil stabilization field trial : interim report III.

DOT National Transportation Integrated Search

2003-11-01

Shrinkage cracks in cement-stabilized bases/subbase can be alleviated by specifying the right cement dosage, or by other additives/procedures that suppress crack susceptibility. A field trial of six 1000 ft test sections to investigate several altern...

Designing Base and Subbase to Resist Environmental Effects on Pavements

DOT National Transportation Integrated Search

2018-02-02

MnDOTs current pavement thickness design procedures do not characterize the effects of subgrade soil frost susceptibility. Previous research indicates frost action is the most severe environmental factor on pavement performance. The most accepted ...

A fully-automatic fast segmentation of the sub-basal layer nerves in corneal images.

PubMed

Guimarães, Pedro; Wigdahl, Jeff; Poletti, Enea; Ruggeri, Alfredo

2014-01-01

Corneal nerves changes have been linked to damage caused by surgical interventions or prolonged contact lens wear. Furthermore nerve tortuosity has been shown to correlate with the severity of diabetic neuropathy. For these reasons there has been an increasing interest on the analysis of these structures. In this work we propose a novel, robust, and fast fully automatic algorithm capable of tracing the sub-basal plexus nerves from human corneal confocal images. We resort to logGabor filters and support vector machines to trace the corneal nerves. The proposed algorithm traced most of the corneal nerves correctly (sensitivity of 0.88 ± 0.06 and false discovery rate of 0.08 ± 0.06). The displayed performance is comparable to a human grader. We believe that the achieved processing time (0.661 ± 0.07 s) and tracing quality are major advantages for the daily clinical practice.

Environmental and Geotechnical Assessment of the Steel Slags as a Material for Road Structure.

PubMed

Sas, Wojciech; Głuchowski, Andrzej; Radziemska, Maja; Dzięcioł, Justyna; Szymański, Alojzy

2015-07-30

Slags are the final solid wastes from the steel industry. Their production from waste and associated materials is a proper implementation of the basic objectives and principles of the waste management. This study aims to investigate the chemical and selected significant geotechnical parameters of steel slag as the alternative materials used in road construction. These investigations are strongly desired for successful application in engineering. Young's modules E , and resilient modules M r showed that their values corresponding with requirements for subbase (principal or auxiliary) and riding surface as well. Tested mechanical properties were conducted in soaked and un-soaked (optimal moisture content) conditions. The designated high content of chromium and zinc are strongly associated with the internal crystal structure of steel slag. The results do not lead to threats when they are applied in roads' structures. Mechanical characterization was obtained by performing California bearing ratio (CBR) tests for steel slag in fixed compaction and moisture content conditions. Moreover, cyclic loading of steel slag was conducted with the application of cyclic California bearing ratio (cCBR) apparatus to characterization of this material as a controlled low-strength material. Finally, field studies that consist of static load plate VSS tests were presented.

A rapid method for soil cement design : Louisiana slope value method.

DOT National Transportation Integrated Search

1964-03-01

The current procedure used by the Louisiana Department of Highways for laboratory design of cement stabilized soil base and subbase courses is taken from standard AASHO test methods, patterned after Portland Cement Association criteria. These methods...

Ocular surface alterations and in vivo confocal microscopic characteristics of corneas in patients with myasthenia gravis.

PubMed

Erkan Turan, Kadriye; Kocabeyoglu, Sibel; Bekircan-Kurt, Can Ebru; Bezci, Figen; Erdem-Ozdamar, Sevim; Irkec, Murat

2018-03-01

To evaluate ocular surface alterations and characteristics of corneal basal epithelium and subbasal nerves in patients with myasthenia gravis. Myasthenia gravis patients (n = 21) and healthy controls (n = 20) were enrolled. All participants underwent ocular surface testing in the following order: tear break-up time, lissamine green staining, Schirmer I test with anesthesia, and Ocular Surface Disease Index questionnaire. The Cochet-Bonnet esthesiometer was used to measure corneal sensitivity. Basal epithelial cells and subbasal nerves were evaluated using in vivo confocal microscopy. Myasthenia gravis patients had higher Ocular Surface Disease Index score (13.9 ± 15.0 vs 1.4 ± 2.2, p < 0.001) and lissamine green staining score (0.6 ± 0.4 vs 0.2 ± 0.4, p = 0.007). Break-up time score (9.3 ± 3.0 vs 9.9 ± 1.9, p = 0.481) and Schirmer I test score (16.5 ± 9.2 vs 19.3 ± 8.4, p = 0.323) did not differ significantly. Corneal sensation was 0.4 g/mm 2 in all eyes. Patients with myasthenia gravis had lower basal epithelial cell density (3775.7 ± 938.1 vs 4983.1 ± 608.5, p < 0.001) and total nerve density (1956.1 ± 373.3 vs 2277.9 ± 405.0, p = 0.012) and higher subbasal nerve tortuosity (1.9 ± 0.8 vs 1.6 ± 0.7, p = 0.007) than controls. A significant increase in Ocular Surface Disease Index scores was found with decreasing basal epithelial cell density (rho = -0.518, p = 0.001). There was a significantly moderate negative correlation between the duration of myasthenia gravis and the number of corneal nerves (rho = -0.497, p = 0.022). Significant alterations of basal epithelial cells and subbasal nerves were demonstrated in myasthenia gravis patients although there was no difference of corneal sensitivity between myasthenia gravis patients and healthy controls. Thus, it should be borne in mind that myasthenia gravis patients deserve further evaluation with regard to ocular surface disease.

Accelerated loading evaluation of subbase layers in pavement performance : tech summary.

DOT National Transportation Integrated Search

2009-04-01

The mighty Mississippi River formed and sculpted most of south Louisiana, creating large areas of alluvial : deposits consisting of soft, wet, and unconsolidated soil layers. Many Louisiana pavements were built in : these areas of naturally low shear...

Full-depth reclamation : new test procedures and recommended updates to specifications.

DOT National Transportation Integrated Search

2012-07-01

Rehabilitating an old pavement by pulverizing and stabilizing the existing pavement is a process referred to : as Full Depth Reclamation (FDR). The stabilized layer becomes either the base or sub-base of the new : pavement structure. This process has...

Field performance evaluations of Illinois aggregates for subgrade replacement and subbase : phase II.

DOT National Transportation Integrated Search

2013-04-01

The project objective was to validate the results from ICT Project R27-1, which characterized in the : laboratory the strength, stiffness, and deformation behaviors of three different aggregate types : commonly used in Illinois for subgrade replaceme...

Corneal Re-innervation and Sensation Recovery in Patients with Herpes Zoster Ophthalmicus: An In Vivo and Ex Vivo Study of Corneal Nerves

PubMed Central

Cruzat, Andrea; Hamrah, Pedram; Cavalcanti, Bernardo M.; Zheng, Lixin; Colby, Kathryn; Pavan-Langston, Deborah

2016-01-01

Purpose To study corneal reinnervation and sensation recovery in Herpes zoster Ophthalmicus (HZO). Methods Two patients with HZO were studied over time with serial corneal esthesiometry and laser in vivo confocal microscopy (IVCM). A Boston keratoprosthesis (B-KPro) type 1 was implanted and the explanted corneal tissues were examined by immunofluorescence histochemistry for βIII-tubulin to stain for corneal nerves. Results The initial central corneal IVCM performed in each patient, showed a complete lack of the subbasal nerve plexus, which was in accordance with severe loss of sensation (0 of 6 cm) measured by esthesiometry. When IVCM was repeated 2 years later prior to undergoing surgery, Case 1 showed a persistent lack of central subbasal nerves and sensation (0 of 6). In contrast, Case 2 showed regeneration of the central subbasal nerves (4,786 µm/mm2) with partial recovery of corneal sensation (2.5 of 6 cm). Immunostaining of the explanted corneal button in Case 1 showed no corneal nerves while Case 2, showed central and peripheral corneal nerves. Eight months after surgery, IVCM was again repeated in the donor tissue around the B-KPro in both patients, to study innervation of the corneal transplant. Case 1 showed no nerves, while Case 2 showed new nerves growing from the periphery into the corneal graft. Conclusions We demonstrate that regaining corneal innervation and function is possible in patients with HZO as shown by corneal sensation, IVCM, and ex-vivo immunostaining, indicating zoster neural damage is not always permanent and it may recover over an extended period of time. PMID:26989956

Leaching behavior of coal combustion products and the environmental implication in road construction

DOT National Transportation Integrated Search

2008-02-01

The use of coal fly ash in road base and sub-base applications can provide better properties and performance, and is superior to it being otherwise disposed and becoming a possible environmental liability. Understanding the metal leaching behavior fo...

Guidance for improving foundation layers to increase pavement performance on local roads.

DOT National Transportation Integrated Search

2014-11-01

This document is the second of two deliverables for the project Optimizing Pavement Base, Subbase, and Subgrade Layers : for Cost and Performance on Local Roads (TR-640). The first deliverable is the 454-page Final Field Data Report. The field : data...

Environmental and Geotechnical Assessment of the Steel Slags as a Material for Road Structure

PubMed Central

Sas, Wojciech; Głuchowski, Andrzej; Radziemska, Maja; Dzięcioł, Justyna; Szymański, Alojzy

2015-01-01

Slags are the final solid wastes from the steel industry. Their production from waste and associated materials is a proper implementation of the basic objectives and principles of the waste management. This study aims to investigate the chemical and selected significant geotechnical parameters of steel slag as the alternative materials used in road construction. These investigations are strongly desired for successful application in engineering. Young’s modules E, and resilient modules Mr showed that their values corresponding with requirements for subbase (principal or auxiliary) and riding surface as well. Tested mechanical properties were conducted in soaked and un-soaked (optimal moisture content) conditions. The designated high content of chromium and zinc are strongly associated with the internal crystal structure of steel slag. The results do not lead to threats when they are applied in roads’ structures. Mechanical characterization was obtained by performing California bearing ratio (CBR) tests for steel slag in fixed compaction and moisture content conditions. Moreover, cyclic loading of steel slag was conducted with the application of cyclic California bearing ratio (cCBR) apparatus to characterization of this material as a controlled low-strength material. Finally, field studies that consist of static load plate VSS tests were presented. PMID:28793477

Leaching behavior of coal combustion products and the environmental implication in road construction : project progress report.

DOT National Transportation Integrated Search

2009-01-01

The use of coal fly ash in road base and sub-base applications can provide better properties and performance, and is superior to it being otherwise disposed and becoming a possible environmental liability. Understanding the metal leaching behavior fo...

Magnitude assessment of free and hydrated limes present in RPCC aggregates : research implementation plan.

DOT National Transportation Integrated Search

2005-10-11

Aggregates obtained from recycled reinforced Portland cement concrete (RPCC) pavement used as base or : subbase may produce tufa in the underdrain outlet pipes. The most likely source of the tufa is related to the : fine aggregate and cement paste. I...

Development of models to estimate the subgrade and subbase layers' resilient modulus from in situ devices test results for construction control.

DOT National Transportation Integrated Search

2008-04-01

The objective of this study was to develop resilient modulus prediction models for possible application in the quality control/quality assurance (QC/QA) procedures during and after the construction of pavement layers. Field and laboratory testing pro...

IL-17 and VEGF are necessary for efficient corneal nerve regeneration

USDA-ARS?s Scientific Manuscript database

The contribution of acute inflammation to sensory nerve regeneration was investigated in the murine cornea using a model of corneal abrasion that removes the stratified epithelium and subbasal nerve plexus. Abrasion induced accumulation of IL-17(+) CCR6(+) yo T cells, neutrophils, and platelets in t...

Leaching behaviour of copper slag, construction and demolition waste and crushed rock used in a full-scale road construction.

PubMed

Lidelöw, Sofia; Mácsik, Josef; Carabante, Ivan; Kumpiene, Jurate

2017-12-15

The leaching behaviour of a road construction with fayalitic copper slag, recycled concrete and crushed rock as sub-base materials was monitored over ten years. All studied materials used in the road construction, including crushed rock, contained concentrations of several elements exceeding the guideline values recommended by the Swedish EPA for total element concentrations for waste materials used in constructions. Despite that, leaching from the road construction under field conditions in general was relatively low. The leachates from the recycled materials contained higher concentrations of several constituents than the leachates from the reference section with crushed rock. The leaching of the elements of interest (Cr, Mo, Ni, Zn) reached peak concentrations during the second and fourth (Cu) years and decreased over the observation period to levels below the Swedish recommended values. Carbonation of the concrete aggregates caused a substantial but short-term increase in the leaching of oxyanions such as chromate. The environmental risks related to element leaching are highest at the beginning of the road life. Ageing of materials or pre-treatment through leaching is needed prior to their use in construction to avoid peak concentrations. Also, the design of road constructions should be adjusted so that recycled materials are covered with low-permeability covers, which would minimize the exposure to atmospheric precipitation and weathering. Copyright © 2017 Elsevier Ltd. All rights reserved.

Greenhouse Gas Emissions from Asphalt Pavement Construction: A Case Study in China

PubMed Central

Ma, Feng; Sha, Aimin; Lin, Ruiyu; Huang, Yue; Wang, Chao

2016-01-01

In China, the construction of asphalt pavement has a significant impact on the environment, and energy use and greenhouse gas (GHG) emissions from asphalt pavement construction have been receiving increasing attention in recent years. At present, there is no universal criterion for the evaluation of GHG emissions in asphalt pavement construction. This paper proposes to define the system boundaries for GHG emissions from asphalt pavement by using a process-based life cycle assessment method. A method for evaluating GHG emissions from asphalt pavement construction is suggested. The paper reports a case study of GHG emissions from a typical asphalt pavement construction project in China. The results show that the greenhouse gas emissions from the mixture mixing phase are the highest, and account for about 54% of the total amount. The second highest GHG emission phase is the production of raw materials. For GHG emissions of cement stabilized base/subbase, the production of raw materials emits the most, about 98%. The GHG emission for cement production alone is about 92%. The results indicate that any measures to reduce GHG emissions from asphalt pavement construction should be focused on the raw materials manufacturing stage. If the raw materials production phase is excluded, the measures to reduce GHG emissions should be aimed at the mixture mixing phase. PMID:27011196

Greenhouse Gas Emissions from Asphalt Pavement Construction: A Case Study in China.

PubMed

Ma, Feng; Sha, Aimin; Lin, Ruiyu; Huang, Yue; Wang, Chao

2016-03-22

In China, the construction of asphalt pavement has a significant impact on the environment, and energy use and greenhouse gas (GHG) emissions from asphalt pavement construction have been receiving increasing attention in recent years. At present, there is no universal criterion for the evaluation of GHG emissions in asphalt pavement construction. This paper proposes to define the system boundaries for GHG emissions from asphalt pavement by using a process-based life cycle assessment method. A method for evaluating GHG emissions from asphalt pavement construction is suggested. The paper reports a case study of GHG emissions from a typical asphalt pavement construction project in China. The results show that the greenhouse gas emissions from the mixture mixing phase are the highest, and account for about 54% of the total amount. The second highest GHG emission phase is the production of raw materials. For GHG emissions of cement stabilized base/subbase, the production of raw materials emits the most, about 98%. The GHG emission for cement production alone is about 92%. The results indicate that any measures to reduce GHG emissions from asphalt pavement construction should be focused on the raw materials manufacturing stage. If the raw materials production phase is excluded, the measures to reduce GHG emissions should be aimed at the mixture mixing phase.

Development of models to estimate the subgrade and subbase layers' resilient modulus from in-situ devices test results for construction control.

DOT National Transportation Integrated Search

2009-05-01

The primary objective of this research was to develop models that predict the resilient modulus of cohesive and granular soils from the test results of various in-situ test devices for possible application in QA/QC during construction of pavement str...

Small fiber neuropathy in women with fibromyalgia. An in vivo assessment using corneal confocal bio-microscopy.

PubMed

Ramírez, Manuel; Martínez-Martínez, Laura-Aline; Hernández-Quintela, Everardo; Velazco-Casapía, Jorge; Vargas, Angélica; Martínez-Lavín, Manuel

2015-10-01

A consistent line of investigation suggests that fibromyalgia is a neuropathic pain syndrome. This outlook has been recently reinforced by several controlled studies that describe decreased small nerve fiber density in skin biopsies of patients with fibromyalgia. The cornea receives the densest small fiber innervation of the body. Corneal confocal bio-microscopy is a new noninvasive method to evaluate small nerve fiber morphology. Our objective was to assess corneal small nerve fiber morphology in patients with fibromyalgia, and to associate corneal nerve microscopic features with neuropathic pain descriptors and other fibromyalgia symptoms. We studied 17 female patients with fibromyalgia and 17 age-matched healthy control subjects. All the participants completed different questionnaires regarding the symptoms of fibromyalgia, including a neuropathic pain survey. A central corneal thickness scan was obtained with a confocal microscope. Nerve measurements were made by a single ophthalmologist without knowledge of the clinical diagnosis. Stromal nerve thickness was defined as the mean value between the widest and the narrowest portion of each analyzed stromal nerve. Corneal sub-basal plexus nerve density was also assessed. Patients with fibromyalgia had stromal nerve thickness of 5.0 ± 1.0 µm (mean ± standard deviation) significantly different from that of control's values (6.1 ± 1.3) p = 0.01. Patients also had decreased sub-basal plexus nerve density per square millimeter (85 ± 29) vs. 107 ± 26 of controls p = 0.02. When controls and patients were grouped together, there was an association between stromal nerve slenderness and neuropathic pain descriptors (Fisher's exact test p = 0.007). Women suffering from fibromyalgia have thinner corneal stromal nerves and diminished sub-basal plexus nerve density when compared to healthy controls. Nerve scarcity is associated with neuropathic pain descriptors. Small fiber neuropathy may play a role in the pathogenesis of fibromyalgia pain. Corneal confocal microscopy could become a useful test in the study of patients with fibromyalgia. Copyright © 2015. Published by Elsevier Inc.

In vivo confocal microscopy indicates an inverse relationship between the sub-basal corneal plexus and the conjunctivalisation in patients with limbal stem cell deficiency.

PubMed

Caro-Magdaleno, Manuel; Alfaro-Juárez, Asunción; Montero-Iruzubieta, Jesús; Fernández-Palacín, Ana; Muñoz-Morales, Ana; Castilla-Martino, Manuel Alberto; Spínola-Muñoz, Consuelo; Rodríguez-de-la-Rúa, Enrique

2018-05-18

Limbal stem cell deficiency (LSCD) is characterised by a marked decrease in limbal stem cells. It is classified primarily using subjective slit-lamp observations. In vivo confocal microscopy (IVCM) can non-invasively provide objective information on the condition of the limbal niche, the corneal epithelial basal cell density and the corneal sub-basal nerve plexus density (SND). We here used IVCM to evaluate changes in SND to improve LSCD classification. We evaluated and classified 38 patients (76 eyes, 44 with LSC and 32 control eyes) using the Rama, López-García and Deng (clinical and confocal) classifications and evaluated the concordance of the confocal and clinical classifications. We constructed a logistic regression model using multivariate analysis to correlate different degrees of conjunctivalisation with IVCM parameters and used receiver operating characteristic (ROC) curve analysis to establish the SND cut-off value with maximum diagnostic sensitivity and specificity. The classification systems correlated moderately at best (kappa, 0.449). The corneal SND of cases (6469±6295 µm/mm 2 ) was less (p<0.001) than in controls (20911±4142 µm/mm 2 ). The SND, but not basal cell density, played a protective role against conjunctivalisation (OR, 0.069; 95% CI 0.008-0.619; p=0.01). An SND cut-off value of 17 215 µm/mm 2 yielded a sensitivity and specificity of 95.5% and 90.6%, respectively, for LSCD diagnosis. The density of the corneal sub-basal nerve plexus was inversely related to conjunctivalisation in LSCD. Further studies are needed to verify this and to elucidate the directionality between these factors. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

An example problem illustrating the application of the national lime association mixture design and testing protocol (MDTP) to ascertain engineering properties of lime-treated subgrades for mechanistic pavement design/analysis.

DOT National Transportation Integrated Search

2001-09-01

This document presents an example of mechanistic design and analysis using a mix design and : testing protocol. More specifically, it addresses the structural properties of lime-treated subgrade, : subbase, and base layers through mechanistic design ...

MX Siting Investigation. Geotechnical Evaluation. Verification Study - Lake Valley, Nevada. Volume I. Synthesis.

DTIC Science & Technology

1981-07-31

attitudes, topo- graphic slopes, evidence of erosional features such as pedi - ments, and the presence or absence of young volcanic rocks. 1 jb. Depth...subgrade, subbase, or 4’ EIM mom ! E-TR-27-LV-J A-34 base. Parameters used to make these qualitative assessments were characteristics related to CBR, frost

Nature based solutions to mitigate soil sealing in urban areas: Results from a 4-year study comparing permeable, porous, and impermeable pavements.

PubMed

Fini, A; Frangi, P; Mori, J; Donzelli, D; Ferrini, F

2017-07-01

Soil sealing is one of the most pervasive forms of soil degradation that follows urbanization and, despite innovative pavements (i.e. pervious) are being installed in urban areas to mitigate it, there is little research on the effects of pervious pavements on soil water and carbon cycle and on the physiology of urban trees. The aim of this 4-year experiment was to assess the effects of three pavements, differing in permeability to water and gases, on some soil physical parameters, and on growth and physiology of newly planted Celtis australis and Fraxinus ornus. Treatments were: 1) impermeable pavement (asphalt on concrete sub-base); 2) permeable pavement (pavers on crushed rock sub-base); 3) porous design (porous pavement on crushed rock sub-base); 4) control (unpaved soil, kept free of weed by chemical control). Soil (temperature, moisture, oxygen content and CO 2 efflux) and plant (above- and below-ground growth, leaf gas exchange, chlorophyll fluorescence, water relations) parameters were measured. All types of pavements altered the water cycle compared to unpaved soil plots, but this disturbance was less intense in porous pavements than in other soil cover types. Porous pavements allowed both higher infiltration and evaporation of water than both pavers and asphalt. Reduction of evaporative cooling from soil paved with permeable and impermeable pavements contributed to significant soil warming: at 20cm depth, soils under concrete pavers and asphalt were 4 and 5°C warmer than soil covered by porous pavements and unpaved soils, respectively. Thus, enhancing evaporation from paved soil by the use of porous pavements may contribute to mitigating urban heat islands. CO 2 greatly accumulated under impermeable and permeable pavements, but not under porous pavements, which showed CO 2 efflux rates similar to control. Soil oxygen slightly decreased only beneath asphalt. Growth of newly planted C. australis and F. ornus was little affected by pavement type. Tree transpiration rapidly depleted soil moisture compared to the not-planted scenario, but soil moisture did not fall below wilting point (particularly in the deeper soil layers, i.e. 40-50cm) in any treatment. While C. australis showed similar leaf gas exchange and water relations in all treatments, F. ornus showed a depression in CO 2 assimilation and slight signs of stress of the photosynthetic apparatus when planted in soil covered with impermeable pavement. The effects of soil cover with different materials on tree growth and physiology were little, because newly planted trees have most of their roots still confined in the unpaved planting pit. Still, the reduction of soil sealing around the planting pit triggered the establishment of sensitive species such as ash. Further research is needed to assess the effects of different pavement types on established, larger trees. Copyright © 2017 Elsevier Inc. All rights reserved.

Crushed aggregates for roads and their properties for frost protection

NASA Astrophysics Data System (ADS)

Kuznetsova, Elena; Willy Danielsen, Svein

2015-04-01

Crushed aggregates for roads and their properties for frost protection Elena Kuznetsova, NTNU and Svein Willy Danielsen, SINTEF With natural (fluvial, glaciofluvial) sand/gravel resources being rapidly depleted in many countries, the last decade has seen a significant trend towards using more alternative materials for construction purpose. In Norway the development and implementation of crushed aggregate technology has been the most important way to get around the problem with increased resource scarcity. Today Norway is one the European countries with the highest percentage of crushed/manufactured aggregates. A crushed product will reveal a different particle size distribution, a sharper, more angular particle shape, and not least - a significantly different mineral composition. The latter may often be characterised by more polymineral composition, and it will also much more depend on the local bedrock. When handled with care and knowledge, these differences can give the user a lot of new opportunities relating to materials design. Norwegian road construction practice has changed significantly during the last 40 years due to the replacement of gravel by crushed rock materials in the granular layers of the pavements. The use of non-processed rock materials from blasting was allowed in the subbase layer until 2012. This was a reason for a lot of problems with frost heaving due to inhomogeneity of this material, and in practice it was difficult to control the size of large stones. Since 2012 there is a requirement that rock materials for use in the subbase layer shall be crushed (Handbook N200, 2014). During the spring 2014 The Norwegian Public Roads Administration introduced a new handbook with requirements for roads construction in Norway, including new specifications for the frost protection layer. When pavements are constructed over moist and/or frost susceptible soils in cold and humid environments, the frost protection layer also becomes a very important part of the road system. According to new specification; the size of large stones for this layer should be maximum 0.5 m (longest edge) or ½ layer thickness. And minimum 30% of stones should be less than 90 mm. Fines content (<0.063 mm) should be maximum 15% of the material less than 22.4 mm. Analysing these new requirements, several questions are arising. First of all how this materials size will affect heat exchange in the layer, secondly - if the allowable fines content will make the materials frost susceptible. For calculations of frost protection layer thickness the knowledge of thermal conductivity of the aggregate layers is required. Handbook for geotechnical investigations of the soils provides this data for natural gravel which is limited by 0.7 - 1.3 W/mK. But when it comes to the crushed rocks, it can be significantly increased due to the higher conductivity of minerals (especially if they contain high amount of quartz), as well as due to higher effective conductivity. In rock-fill materials, i.e. materials with large particles and low degree of saturation, convection and radiation are the predominant heat transfer mechanisms. Convection and radiation can increase the effective conductivity by factor 2-10. Lebeau and Konrad (2007) showed that convection heat transfer could lead to the formation of undesirable permafrost conditions in toe drains of embankment dams located in Northern Quebec, i.e. in areas where there are no naturally occurring permafrost soils. In a frost design method the required parameter values of crushed rock aggregates are thermal conductivity, density and water content. The heat transfer during the freezing of natural soils is assumed proportional to thermal conductivity of the material. In a coarse-grained material with abundant pore space, convective heat transfer and radiation may be a considerable factor, sometimes even more significant than conduction. Specifications used by pavement engineers in most countries are solely based on grain size distribution and allowable fines content. The presence of fines in these layers can modify their frost susceptibility and cause severe degradation, especially with recent trends in climate change leading to more freeze-thaw cycle events during the winter season (Konrad & Lemieux, 2005). A higher content of fines due to sub-base wear will increase moisture in the structure and the risk of subsequent frost heave. Guthrie and Hermansson (2003) showed by laboratory tests in a closed drainage system that retained water in a soil sample was sufficient to feed the frost heave. Even though the most severe frost heave in real pavements occurs when the material is in contact with free water (open drainage system) we wanted to study freezing behaviour in aggregate materials having initial water contents (closed drainage system). The study presented here is part of a larger research program to investigate the properties of crushed rock materials in relation to frost heaving in the frost protection layer. An important issue will be the resistivity for frost penetration due to presence of water and fine particles. Due to new requirements for allowed fines content, it's essential to investigate if increased amount of stones <0.063 mm together with increasing of water content in the frost protection layer, will not lead to more frost heave problems. The objective of the present study was to investigate the influence of fines on the freezing characteristics of well-graded crushed aggregate in a closed drainage system. The reason for it is the understanding of the behaviour of the aggregate material when there is no access for any other water resources besides existing in the pavement (ex., from rain-fall). At the same time we did some estimation of thermal conductivity and frost penetration depth for all tested material using different aggregate density and water content. Experiments were made by using greenstones (methamorphic basaltic lava), collected in Vassfjellet, area of Sor-Trondelag, Norway. This material is commonly used for base, subbase and subgrade layers in roads and railways in the area. The material is of average strength (in Norway) and represents a typical material for this purpose. The influence of fines on the frost susceptibility of crushed rock aggregates in a closed drainage system was established by laboratory frost heave tests. A total of 10 samples with fines contents of 5%, 10% and 15% respectively were subjected to freezing in constant temperature. Also we made calculations for thermal conductivity by using Johansen's (1975) model. The study led to the following results: 1. Even for a closed system, without access of water, frost heave can occur just from redistributing water if the following conditions are met: a) Fines content exceeds 10%, b) Water content is around 7% 2. As to frost susceptibility classification, the crushed rock aggregates with 5% and 10% of fine material, fraction less than 0.063 mm, show negligible and/or low frost susceptibility. Those with 15% show medium frost susceptibility 3. Dry thermal conductivity for crushed rock samples, estimated by using Johansen's model, showed that an increase of dry density of 15% led to an increase of thermal conductivity of 75%. 4. Latent heat of fusion for all samples shows significant dependence on the water content, and less on the density 5. Highest calculated frost penetration depth was observed for dry samples. For other samples no big variation was found between 4% and 7% water content.

Soil Stabilization for Roadways and Airfields

DTIC Science & Technology

1987-07-01

the possibility of accidents and minimize health hazards. Al 1 Occupational Safety and Health Act requirements shall be observed. 8. Method of...v ELS Section Title Page G. Selection of Asphalt Type and Asphalt Content ........ . ... .. 86 H. Safety Precautions, Limitations of Use and...for Lime Fly Ash-Aggregate Base/Subbase Courses ...... ............. ?16 SECTION III - Typical Specification for Road - Mixed Asphalt fyr BasP and

Assessment of dynamic surface leaching of monolithic surface road materials.

PubMed

Paulus, Hélène; Schick, Joachim; Poirier, Jean-Eric

2016-07-01

Construction materials have to satisfy, among others, health and environment requirements. To check the environmental compatibility of road construction materials, release of hazardous substances into water must be assessed. Literature mostly describes the leaching behaviour of recycled aggregates for potential use in base or sub-base layers of roads. But little is known about the release of soluble substances by materials mixed with binders and compacted for intended use on road surface. In the present study, we thus performed a diffusion test with sequential renewal of water during a 64 day period according to CEN/TS 16637-2 specifications, on asphalt concretes and hydraulically bound monoliths, two common surface road materials. It is shown that release of dangerous substances is limited in these hydrodynamic conditions. It was particularly true for asphalt concrete leachates where no metallic trace element, sulphate, chloride or fluoride ion could be quantified. This is because of the low hydraulic conductivity and the low polarity of the petroleum hydrocarbon binder of these specimens. For hydraulically bound materials around 20,000 mg/m(2) of sulphate diffused from the monoliths. It is one order of magnitude higher than chloride diffusion and two orders of magnitude higher than fluoride release. No metallic trace element, except small quantities of copper in the last eluate could be quantified. No adverse effect is to be expected for human and environmental health from the leachates of these compacted surface road construction materials, because all the measured parameters were below EU (Council Directive 98/83/EC) or WHO guidelines for drinking water standards. Copyright © 2016 Elsevier Ltd. All rights reserved.

MX Siting Investigation. Geotechnical Evaluation. Volume I. Arizona Verification Studies, FY 79, and Geotechnical Data, La Posa CDP, Arizona.

DTIC Science & Technology

1979-11-15

COMPACTION 7-12 [2] 9 SUITABILITY AS ROAD SUBGRADE (’) poor to fair lair to go SUITABILITY AS ROAD SUBBASE OR BASE (1) poor poor to fai aJ 2.1-10.9 1.1...wave velocity of 9350 fps (2850 mps). These variable seismic wave velocities indicate nonuniformity in subsoil density and cementation. Electrical

Development and Application of a Three-Dimensional Finite Element Vapor Intrusion Model

PubMed Central

Pennell, Kelly G.; Bozkurt, Ozgur; Suuberg, Eric M.

2010-01-01

Details of a three-dimensional finite element model of soil vapor intrusion, including the overall modeling process and the stepwise approach, are provided. The model is a quantitative modeling tool that can help guide vapor intrusion characterization efforts. It solves the soil gas continuity equation coupled with the chemical transport equation, allowing for both advective and diffusive transport. Three-dimensional pressure, velocity, and chemical concentration fields are produced from the model. Results from simulations involving common site features, such as impervious surfaces, porous foundation sub-base material, and adjacent structures are summarized herein. The results suggest that site-specific features are important to consider when characterizing vapor intrusion risks. More importantly, the results suggest that soil gas or subslab gas samples taken without proper regard for particular site features may not be suitable for evaluating vapor intrusion risks; rather, careful attention needs to be given to the many factors that affect chemical transport into and around buildings. PMID:19418819

The Effect of Autologous Platelet Lysate Eye Drops: An In Vivo Confocal Microscopy Study

PubMed Central

Fea, Antonio M.; Testa, Valeria; Machetta, Federica; Parisi, Simone; D'Antico, Sergio; Spinetta, Roberta; Fusaro, Enrico; Grignolo, Federico M.

2016-01-01

Purpose. To determine the effectiveness of autologous platelet lysate (APL) eye drops in patients with primary Sjögren syndrome (SS) dry eye, refractory to standard therapy, in comparison with patients treated with artificial tears. We focused on the effect of APL on cornea morphology with the in vivo confocal microscopy (IVCM). Methods. Patients were assigned to two groups: group A used autologous platelet lysate QID, and group B used preservative-free artificial tears QID, for 90 days. Ophthalmological assessments included ocular surface disease index (OSDI), best corrected visual acuity (BCVA), Schirmer test, fluorescein score, and breakup time (BUT). A subgroup of patients in group A underwent IVCM: corneal basal epithelium, subbasal nerves, Langerhans cells, anterior stroma activated keratocytes, and reflectivity were evaluated. Results. 60 eyes of 30 patients were enrolled; in group A (n = 20 patients) mean OSDI, fluorescein score, and BUT showed significant improvement compared with group B (n = 10 patients). The IVCM showed a significant increase in basal epithelium cells density and subbasal nerve plexus density and number and a decrease in Langerhans cells density (p < 0.05). Conclusion. APL was found effective in the treatment of SS dry eye. IVCM seems to be a useful tool to visualize cornea morphologic modifications. PMID:27200376

The Effect of Autologous Platelet Lysate Eye Drops: An In Vivo Confocal Microscopy Study.

PubMed

Fea, Antonio M; Aragno, Vittoria; Testa, Valeria; Machetta, Federica; Parisi, Simone; D'Antico, Sergio; Spinetta, Roberta; Fusaro, Enrico; Grignolo, Federico M

2016-01-01

Purpose. To determine the effectiveness of autologous platelet lysate (APL) eye drops in patients with primary Sjögren syndrome (SS) dry eye, refractory to standard therapy, in comparison with patients treated with artificial tears. We focused on the effect of APL on cornea morphology with the in vivo confocal microscopy (IVCM). Methods. Patients were assigned to two groups: group A used autologous platelet lysate QID, and group B used preservative-free artificial tears QID, for 90 days. Ophthalmological assessments included ocular surface disease index (OSDI), best corrected visual acuity (BCVA), Schirmer test, fluorescein score, and breakup time (BUT). A subgroup of patients in group A underwent IVCM: corneal basal epithelium, subbasal nerves, Langerhans cells, anterior stroma activated keratocytes, and reflectivity were evaluated. Results. 60 eyes of 30 patients were enrolled; in group A (n = 20 patients) mean OSDI, fluorescein score, and BUT showed significant improvement compared with group B (n = 10 patients). The IVCM showed a significant increase in basal epithelium cells density and subbasal nerve plexus density and number and a decrease in Langerhans cells density (p < 0.05). Conclusion. APL was found effective in the treatment of SS dry eye. IVCM seems to be a useful tool to visualize cornea morphologic modifications.

Exploring the techno-economic feasibility of mine rock waste utilisation in road works: The case of a mining deposit in Ghana.

PubMed

Agyeman, Stephen; Ampadu, Samuel I K

2016-02-01

Mine rock waste, which is the rock material removed in order to access and mine ore, is free from gold processing chemical contaminants but presents a significant environmental challenge owing to the large volumes involved. One way of mitigating the environmental and safety challenges posed by the large volume of mine rock waste stockpiled in mining communities is to find uses of this material as a substitute for rock aggregates in construction. This article reports on a study conducted to evaluate the engineering properties of such a mine deposit to determine its suitability for use as road pavement material. Samples of mine rock waste, derived from the granitic and granodioritic intrusive units overlying the gold-bearing metavolcanic rock and volcano-clastic sediments of a gold mining area in Ghana, were obtained from three mine rock waste disposal facilities and subjected to a battery of laboratory tests to determine their physical, mechanical, geotechnical, geometrical and durability properties. The overall conclusion was that the mine rock waste met all the requirements of the Ghana Ministry of Transportation specification for use as aggregates for crushed rock subbase, base and surface dressing chippings for road pavements. The recommendation is to process it into the required sizes for the various applications. © The Author(s) 2015.

A New Aedes (Finlaya) of the Niveus-Subgroup (Diptera: Culicidae)

DTIC Science & Technology

1987-01-01

Cobbold ) (Gould et al. 1982), was described by Knight (1978) as Aedes (Finlaya) harinasutai. The second one, their Sp. 1, is described here. METHODS...detail, other than setal orientation, marking the joint border of these two areas. At least some setae are present along the entire length of each of...beyond middle or even to apex, this marking broadest from basally or subbasally to middle and narrowing distally from thereafter; hindfemur with

Geopolymers based on the valorization of Municipal Solid Waste Incineration residues

NASA Astrophysics Data System (ADS)

Giro-Paloma, J.; Maldonado-Alameda, A.; Formosa, J.; Barbieri, L.; Chimenos, J. M.; Lancellotti, I.

2017-10-01

The proper management of Municipal Solid Waste (MSW) has become one of the main environmental commitments for developed countries due to the uncontrolled growth of waste caused by the consumption patterns of modern societies. Nowadays, municipal solid waste incineration (MSWI) is one of the most feasible solutions and it is estimated to increase in Europe where the accessibility of landfill is restricted. Bottom ash (BA) is the most significant by-product from MSWI as it accounts for 85 - 95 % of the solid product resulting from combustion, which is classified as a non-hazardous residue that can be revalorized as a secondary aggregate in road sub-base, bulk lightweight filler in construction. In this way, revalorization of weathered BA (WBA) for the production of geopolymers may be a good alternative to common reuse as secondary aggregate material; however, the chemical process to obtain these materials involves several challenges that could disturb the stability of the material, mainly from the environmental point of view. Accordingly, it is necessary that geopolymers are able to stabilize heavy metals contained in the WBA in order to be classified as non-hazardous materials. In this regard, the SiO2/Al2O3 ratio plays an important role for the encapsulation of heavy metals and other toxic elements. The aim of this research is to formulate geopolymers starting from the 0 - 2 mm particle size fraction of WBA, as a unique raw material used as aluminumsilicate precursor. Likewise, leaching tests of the geopolymers formulated were performed to assess their environmental impact. The findings show that it is possible to formulate geopolymers using 100 % WBA as precursor, although more investigations are needed to sustain that geopolymer obtained can be considered as non-hazardous materials.

Reproducing ten years of road ageing--accelerated carbonation and leaching of EAF steel slag.

PubMed

Suer, Pascal; Lindqvist, Jan-Erik; Arm, Maria; Frogner-Kockum, Paul

2009-09-01

Reuse of industrial aggregates is still hindered by concern for their long-term properties. This paper proposes a laboratory method for accelerated ageing of steel slag, to predict environmental and technical properties, starting from fresh slag. Ageing processes in a 10-year old asphalt road with steel slag of electric arc furnace (EAF) type in the subbase were identified by scanning electron microscopy (SEM) and leaching tests. Samples from the road centre and the pavement edge were compared with each other and with samples of fresh slag. It was found that slag from the pavement edge showed traces of carbonation and leaching processes, whereas the road centre material was nearly identical to fresh slag, in spite of an accessible particle structure. Batches of moisturized road centre material exposed to oxygen, nitrogen or carbon dioxide (CO2) were used for accelerated ageing. Time (7-14 days), temperature (20-40 degrees C) and initial slag moisture content (8-20%) were varied to achieve the carbonation (decrease in pH) and leaching that was observed in the pavement edge material. After ageing, water was added to assess leaching of metals and macroelements. 12% moisture, CO2 and seven days at 40 degrees C gave the lowest pH value. This also reproduced the observed ageing effect for Ca, Cu, Ba, Fe, Mn, Pb, Ca (decreased leaching) and for V, Si, and Al (increased leaching). However, ageing effects on SO4, DOC and Cr were not reproduced.

2005 Tri-Service Infrastructure Systems Conference and Exhibition. Volume 8, Track 8 Continued

DTIC Science & Technology

2005-08-04

Dennis Mekkers and Daniel M. Katz Current Research in Fate Current Research in Fate & Transport of Chemical and Biological Contaminants in Water...past boil activity, FSg = 1 • Minor boil or heavy seepage, FSg = 1.25 • Major boil activity, FSg = 1.5 The ratio 1:1.5 approximates (Critical State...prolonging life of road – SSB performed best under heavy traffic – If heavy traffic is possible, road should include a subbase Summary • Maintenance

Basic Aspects of Deep Soil Mixing Technology Control

NASA Astrophysics Data System (ADS)

Egorova, Alexandra A.; Rybak, Jarosław; Stefaniuk, Damian; Zajączkowski, Przemysław

2017-10-01

Improving a soil is a process of increasing its physical/mechanical properties without changing its natural structure. Improvement of soil subbase is reached by means of the knitted materials, or other methods when strong connection between soil particles is established. The method of DSM (Deep Soil Mixing) columns has been invented in Japan in 1970s. The main reason of designing cement-soil columns is to improve properties of local soils (such as strength and stiffness) by mixing them with various cementing materials. Cement and calcium are the most commonly used binders. However new research undertaken worldwide proves that apart from these materials, also gypsum or fly ashes can also be successfully implemented. As the Deep Soil Mixing is still being under development, anticipating mechanical properties of columns in particular soils and the usage of cementing materials in formed columns is very difficult and often inappropriate to predict. That is why a research is carried out in order to find out what binders and mixing technology should be used. The paper presents several remarks on the testing procedures related to quality and capacity control of Deep Soil Mixing columns. Soil improvement methods, their advantages and limitations are briefly described. The authors analyse the suitability of selected testing methods on subsequent stages of design and execution of special foundations works. Chosen examples from engineering practice form the basis for recommendations for the control procedures. Presented case studies concerning testing the on capacity field samples and laboratory procedures on various categories of soil-cement samples were picked from R&D and consulting works offered by Wroclaw University of Science and Technology. Special emphasis is paid to climate conditions which may affect the availability of performing and controlling of DSM techniques in polar zones, with a special regard to sample curing.

Mechanistic design concepts for conventional flexible pavements

NASA Astrophysics Data System (ADS)

Elliott, R. P.; Thompson, M. R.

1985-02-01

Mechanical design concepts for convetional flexible pavement (asphalt concrete (AC) surface plus granular base/subbase) for highways are proposed and validated. The procedure is based on ILLI-PAVE, a stress dependent finite element computer program, coupled with appropriate transfer functions. Two design criteria are considered: AC flexural fatigue cracking and subgrade rutting. Algorithms were developed relating pavement response parameters (stresses, strains, deflections) to AC thickness, AC moduli, granular layer thickness, and subgrade moduli. Extensive analyses of the AASHO Road Test flexible pavement data are presented supporting the validity of the proposed concepts.

Geotechnical and mineralogical characteristics of marl deposits in Jordan

NASA Astrophysics Data System (ADS)

Shaqour, Fathi M.; Jarrar, Ghaleb; Hencher, Steve; Kuisi, Mostafa

2008-10-01

Marls and marly limestone deposits cover most of Northern Jordan, where Amman City and its suburbs are located. These deposits serve as foundations for most buildings and roads as well as fill material for structural back filling, especially road bases and sub-bases. The present study aims at investigating the geotechnical characteristics and mineral composition of the marl units of these deposits through field investigations and laboratory testing. Using X-ray diffraction technique along with chemical analysis, representative samples of marl horizons were tested for mineral composition, and for a set of index and geotechnical properties including: specific gravity, grain size, Atterberg limits, Proctor compaction and shear strength properties. The test results show a positive linear relationship as expected between the clay content and both liquid and plastic limits. The tests results also show an inverse linear relationship between the clay content and the maximum dry density in both standard and modified compaction. This is attributed to the adsorption of water by the clay minerals. The relationship is more prominent in the case of modified compaction test. The results also indicate a similar relationship for the angle of internal friction. No clear correlation between cohesion and clay content was apparent.

Study on Flexible Pavement Failures in Soft Soil Tropical Regions

NASA Astrophysics Data System (ADS)

Jayakumar, M.; Chee Soon, Lee

2015-04-01

Road network system experienced rapid upgrowth since ages ago and it started developing in Malaysia during the colonization of British due to its significant impacts in transportation field. Flexible pavement, the major road network in Malaysia, has been deteriorating by various types of distresses which cause descending serviceability of the pavement structure. This paper discusses the pavement condition assessment carried out in Sarawak and Sabah, Malaysia to have design solutions for flexible pavement failures. Field tests were conducted to examine the subgrade strength of existing roads in Sarawak at various failure locations, to assess the impact of subgrade strength on pavement failures. Research outcomes from field condition assessment and subgrade testing showed that the critical causes of pavement failures are inadequate design and maintenance of drainage system and shoulder cross fall, along with inadequate pavement thickness provided by may be assuming the conservative value of soil strength at optimum moisture content, whereas the exiting and expected subgrade strengths at equilibrium moisture content are far below. Our further research shows that stabilized existing recycled asphalt and base materials to use as a sub-base along with bitumen stabilized open graded base in the pavement composition may be a viable solution for pavement failures.

In vivo morphology of the limbal palisades of vogt correlates with progressive stem cell deficiency in aniridia-related keratopathy.

PubMed

Lagali, Neil; Edén, Ulla; Utheim, Tor Paaske; Chen, Xiangjun; Riise, Ruth; Dellby, Anette; Fagerholm, Per

2013-08-07

To investigate morphologic alterations in the limbal palisades of Vogt in a progressive form of limbal stem cell deficiency. Twenty Norwegian subjects (40 eyes) with congenital aniridia and 9 healthy family members (18 eyes) without aniridia were examined. Clinical grade of aniridia-related keratopathy (ARK) was assessed by slit-lamp biomicroscopy, and tear production and quality, corneal thickness, and sensitivity were additionally measured. The superior and inferior limbal palisades of Vogt and central cornea were examined by laser scanning in vivo confocal microscopy (IVCM). In an aniridia patient with grade 0 ARK, a transparent cornea and normal limbal palisade morphology were found. In grade 1 ARK, 5 of 12 eyes had degraded palisade structures. In the remaining grade 1 eyes and in all 20 eyes with stage 2, 3, and 4 ARK, palisade structures were absent by IVCM. Increasing ARK grade significantly correlated with reduced visual acuity and corneal sensitivity, increased corneal thickness, degree of degradation of superior and inferior palisade structures, reduced peripheral nerves, increased inflammatory cell invasion, and reduced density of basal epithelial cells and central subbasal nerves. Moreover, limbal basal epithelial cell density and central corneal subbasal nerve density were both significantly reduced in aniridia compared to healthy corneas (P = 0.002 and 0.003, respectively). Progression of limbal stem cell deficiency in aniridia correlates with degradation of palisade structures, gradual transformation of epithelial phenotype, onset of inflammation, and a corneal nerve deficit. IVCM can be useful in monitoring early- to late-stage degenerative changes in stem cell-deficient patients.

Changes in rabbit corneal innervation induced by the topical application of benzalkonium chloride.

PubMed

Chen, Wensheng; Zhang, Zhenhao; Hu, Jiaoyue; Xie, Hui; Pan, Juxin; Dong, Nuo; Liu, Zuguo

2013-12-01

To investigate the effect of benzalkonium chloride (BAK) on corneal nerves. Fifty-four adult New Zealand Albino rabbits were randomly divided into 3 groups. BAK at concentrations of 0.005%, 0.01%, or 0.02% was applied once daily to 1 eye of each rabbit for 9 days. The contralateral untreated eyes were used as controls. Corneal mechanical sensitivity, aqueous tear production, tear break-up time (BUT), fluorescein, and Rose Bengal staining scores were compared with those of control values on days 3, 6, and 9. Corneal whole mounts were immunostained with a specific antitubulin βIII antibody to label nerve fibers. Epithelial superficial nerve terminal, subbasal, and stromal nerve fiber densities were quantified. The structure of the central cornea was examined by means of in vivo confocal microscopy on day 9. The topical application of BAK resulted in lower corneal sensitivity and higher Rose Bengal staining scores on day 3, whereas there were no significant changes in the BUT, Schirmer, and corneal fluorescein scores. Decreased nerve densities in superficial and subbasal layers were observed in BAK-treated eyes on days 3 and 6, respectively. The eyes treated with 0.02% BAK exhibited significantly reduced Schirmer scores, BUT, and stromal nerve fiber density, and increased fluorescein staining scores on day 9. Corneal superficial epithelial cell size was significantly larger in all BAK-treated eyes compared with that in control eyes. The topical application of BAK can quickly cause corneal hypoesthesia without tear deficiency. Changes in corneal innervation significantly correlate with BAK-induced ocular surface changes.

Evaluation of corneal changes after conventional versus accelerated corneal cross-linking: a randomized controlled trial.

PubMed

Hashemian, Hesam; Jabbarvand, Mahmoud; Khodaparast, Mehdi; Ameli, Kambiz

2014-12-01

To evaluate the outcome of accelerated and conventional corneal cross-linking (CXL) procedures regarding their effect on morphological and optical properties of the cornea. One hundred fifty-three eyes of 153 patients were evaluated before and during a 15-month follow-up period after CXL (76 eyes in the conventional group and 77 eyes in the accelerated group). Measured variables include corrected distance visual acuity (CDVA), uncorrected distance visual acuity (UDVA), refraction, maximum keratometry, endothelial cell density, anterior and posterior stromal keratocyte density, and subbasal nerve density. All variables were compared between the two study groups. Cylindrical and spherical components of refraction improved significantly during 15 months of follow-up. No difference was observed between the two study groups. UDVA and CDVA improved in the same manner, with no intergroup differences. Endothelial cell density did not change significantly during the follow-up period in either group. K-max increased slightly in the first month of the follow-up, but started to decrease at postoperative visits without any significant difference in the two groups. Anterior stromal keratocyte density and subbasal nerve density decreased significantly in both groups 1 month postoperatively. Both variables had a more significant decrease in the conventional group at all visits before the 1-year visit. At the final 15-month visit, there were no significant differences in any value between the two groups. Accelerated and conventional CXL seem to have a comparable and acceptable effect on keratoconus in the short-term follow-up period. Copyright 2014, SLACK Incorporated.

Instability improvement of the subgrade soils by lime addition at Borg El-Arab, Alexandria, Egypt

NASA Astrophysics Data System (ADS)

El Shinawi, A.

2017-06-01

Subgrade soils can affect the stability of any construction elsewhere, instability problems were found at Borg El-Arab, Alexandria, Egypt. This paper investigates geoengineering properties of lime treated subgrade soils at Borg El-Arab. Basic laboratory tests, such as water content, wet and dry density, grain size, specific gravity and Atterberg limits, were performed for twenty-five samples. Moisture-density (compaction); California Bearing Ratio (CBR) and Unconfined Compression Strength (UCS) were conducted on treated and natural soils. The measured geotechnical parameters of the treated soil shows that 6% lime is good enough to stabilize the subgrade soils. It was found that by adding lime, samples shifted to coarser side, Atterberg limits values of the treated soil samples decreased and this will improve the soil to be more stable. On the other hand, Subgrade soils improved as a result of the bonding fine particles, cemented together to form larger size and reduce the plastiCity index which increase soils strength. The environmental scanning electron microscope (ESEM) is point to the presence of innovative aggregated cement materials which reduce the porosity and increase the strength as a long-term curing. Consequently, the mixture of soil with the lime has acceptable mechanical characteristics where, it composed of a high strength base or sub-base materials and this mixture considered as subgrade soil for stabilizations and mitigation the instability problems that found at Borg Al-Arab, Egypt.

Utilize Cementitious High Carbon Fly Ash (CHCFA) to Stabilize Cold In-Place Recycled (CIR) Asphalt Pavement as Base Coarse

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

Wen, Haifang; Li, Xiaojun; Edil, Tuncer

The purpose of this study was to evaluate the performance of cementitious high carbon fly ash (CHCFA) stabilized recycled asphalt pavement as a base course material in a real world setting. Three test road cells were built at MnROAD facility in Minnesota. These cells have the same asphalt surface layers, subbases, and subgrades, but three different base courses: conventional crushed aggregates, untreated recycled pavement materials (RPM), and CHCFA stabilized RPM materials. During and after the construction of the three cells, laboratory and field tests were carried out to characterize the material properties. The test results were used in the mechanistic-empiricalmore » pavement design guide (MEPDG) to predict the pavement performance. Based on the performance prediction, the life cycle analyses of cost, energy consumption, and greenhouse gasses were performed. The leaching impacts of these three types of base materials were compared. The laboratory and field tests showed that fly ash stabilized RPM had higher modulus than crushed aggregate and RPM did. Based on the MEPDG performance prediction, the service life of the Cell 79 containing fly ash stabilized RPM, is 23.5 years, which is about twice the service life (11 years) of the Cell 77 with RPM base, and about three times the service life (7.5 years) of the Cell 78 with crushed aggregate base. The life cycle analysis indicated that the usage of the fly ash stabilized RPM as the base of the flexible pavement can significantly reduce the life cycle cost, the energy consumption, the greenhouse gases emission. Concentrations of many trace elements, particularly those with relatively low water quality standards, diminish over time as water flows through the pavement profile. For many elements, concentrations below US water drinking water quality standards are attained at the bottom of the pavement profile within 2-4 pore volumes of flow.« less

The Application of Optimum Value Engineering Design and Construction Techniques to the United States Navy’s Housing Construction Contract Request for Proposal.

DTIC Science & Technology

1988-05-01

thick asphalt pavement and a unit cost of $10/sy for subbase, binder and wearing courses (22), the following costs can be considered: Road Width Cofts...on exposed surfaces, whereas concrete and asphalt absorb and then transmit heat. This is the same rationale used in selecting a white roof over a...Surfaces Item Avg±L !9PRe± M! Trees 80 Grass Lawn i11 Wall Surface 130 ... Asphalt 160 (From Energy Efficient Site Desgn) What constitutes a good site

Omega-3 supplementation is neuroprotective to corneal nerves in dry eye disease: a pilot study.

PubMed

Chinnery, Holly R; Naranjo Golborne, Cecilia; Downie, Laura E

2017-07-01

To investigate whether oral, long-chain omega-3 (ω-3) essential fatty acid (EFA) supplementation, for 3 months, induces changes to the central corneal sub-basal nerve plexus in dry eye disease and whether nerve alterations correlate with clinical findings. This prospective, comparative study involved the final 12 participants enrolled in a randomised, double-masked, placebo-controlled clinical trial of 60 participants with moderate dry eye disease. Participants received either placebo (olive oil 1500 mg/day; n = 4) or ω-3 EFA supplements (~1000 mg/day eicosapentaenoic acid + ~500 mg/day docosahexaenoic acid; n = 8) for 90 days. The main outcome measure was the mean change in central corneal sub-basal plexus nerve parameters between days one and 90, quantified using in vivo confocal microscopy. Secondary outcomes included mean change in tear osmolarity, corneal dendritic cell density and basal epithelial cell density. Compared with baseline, the reduction in OSDI score and tear osmolarity at day 90 were greater in the ω-3 EFA group than the placebo group (OSDI: ω-3 EFA, mean ± SEM: -15.6 ± 2.8 vs placebo: -2.8 ± 4.1 units, t 5 = 2.6, p = 0.04; tearosmolarity: ω-3 EFA: -22.63 ± 5.7 vs placebo: -8 ± 2.7 mOsmol/L, t 9 = 2.3, p = 0.04). At day 90, corneal total nerve branch density (CTBD: 91.1 ± 8.6 vs 45.1 ± 13.4 branches/mm 2 , F 1,10 = 14, p = 0.004) and corneal nerve branch density on the main fibre (CNBD: 63.4 ± 6.5 vs 27.9 ± 11.5 branches/mm 2 , F 1,10 = 6, p = 0.03) were higher in the ω-3 EFA group compared with placebo. Relative to day 1, CNBD (branches/mm 2 ) increased at day 90 in the ω-3 EFA group (+20.0 ± 9.2, t 8 = 3.2 p = 0.01) compared with placebo (-10.8 ± 3.2). Similar changes were evident for corneal nerve fibre length (CNFL, mm/mm 2 ), which increased from baseline at day 90 in the omega-3 EFA group (+2.9 ± 1.6, t 8 = 3.4 p = 0.01) compared with placebo (-2.7 ± 0.5). There was a negative correlation between CTBD and tear osmolarity (r 10 = -0.70, p = 0.01). No significant changes were observed for basal epithelial cell or corneal dendritic cell density. These pilot study findings suggest that ω-3 EFA supplementation imparts neuroprotective effects in the corneal sub-basal plexus that correlate with the extent of tear osmolarity normalisation. © 2017 The Authors Ophthalmic & Physiological Optics © 2017 The College of Optometrists.

Strength and microstructure characteristics of the recycled rubber tire-sand mixtures as lightweight backfill.

PubMed

Zhang, Tao; Cai, Guojun; Duan, Weihong

2018-02-01

The disposal of scrap rubber tires has induced critical environmental issue worldwide due to the rapid increase in the number of vehicles. Recycled scrap tires as a construction material in civil engineering have significant environmental benefits from a waste management perspective. A systematic study that deals with strength and microstructure characteristics of the rubber-sand mixtures is initiated, and mechanical response of the mixtures is discussed in this investigation. Experiments were conducted to evaluate the effects of rubber fraction on the basic properties including mass density (ρ), stress-strain characteristics, shear strength, and unconfined compression strength (q u ) of the rubber-sand mixtures. Additionally, scanning electron microscopy (SEM) was carried out to reveal the microstructure characteristics of the mixtures with various rubber fractions. A discussion on the micromechanics of the mixtures also was conducted. This study demonstrates that the ρ, friction angle, and q u decrease linearly with an increase in rubber fraction, whereas shear strain at peak increases. The stress-strain characteristics of the rubber-sand mixtures shift from brittle to ductile as the rubber fraction increase. These changes are attributed to remarkably lower stiffness and higher compressibility of the rubber particle compared with those of the conventional mineral aggregates. With an increase in the rubber fraction, the mechanical response of rubber-sand mixtures exhibits two types: sand-like material and rubber-like material. Rubber particle possesses the capacity to prevent the contacted sand particles from sliding at lower rubber fraction, whereas it transmits the applied loadings as the rubber fraction increased. This outcome reinforces the practicability of using recycled rubber tire-sand mixtures as a lightweight backfill in subbase/base applications.

In vivo laser confocal microscopy of Bowman's layer of the cornea.

PubMed

Kobayashi, Akira; Yokogawa, Hideaki; Sugiyama, Kazuhisa

2006-12-01

To investigate in vivo microstructures of Bowman's layer in normal human subjects using a cornea-specific in vivo laser scanning confocal microscope (Heidelberg Retina Tomograph 2 Rostock Cornea Module, HRT2-RCM). Single-center, prospective, observational case series. Nineteen normal volunteers (10 male, 9 female; mean age, 46.2+/-21.7 years [range, 18-77]). The central and peripheral cornea, specifically the epithelium, Bowman's layer, and its subjacent stroma, were examined using the HRT2-RCM. Selected images of the corneal layers were evaluated qualitatively for the shape and degree of light reflection of the microstructures. In all subjects, normal epithelial (superficial, wing, basal) cells, subbasal nerve plexus, Bowman's layer, and its subjacent stoma were observed clearly. However, in all subjects, polymorphic structures composed of fibrillar materials with less reflectivity than corneal nerves were observed beneath Bowman's layer. After application of pressure by a Tomo-cap, we observed numerous ridges that protruded into the epithelial basal and wing cell layers. Superficial stromal striae were also observed. These ridges and striae corresponded exactly to the orientation of the fibrous structures located beneath the epithelial cells. We report for the first time, the presence of polymorphic structures composed of fibrillar materials (K-structures) beneath Bowman's layer in normal human subjects, detected by HRT2-RCM. We surmise that these microstructures may correspond to the modified and condensed anterior stromal collagen fibers/lamellae that merge into Bowman's layer and that these fibrillar materials may be responsible for the formation of the anterior corneal mosaic. Further investigation of these microstructures in diseased eyes may provide insights into their pathophysiologic role in Bowman's layer.

Corneal confocal microscopy and dry eye findings in contact lens discomfort patients.

PubMed

Dogan, Aysun Sanal; Gurdal, Canan; Arslan, Nese

2018-02-01

To evaluate the corneal confocal microscopy and dry eye findings in patients with contact lens discomfort. The study included 3 groups of participants: Contact lens wearers using silicone hydrogel soft contact lenses who are symptomatic (CLD, n=15) or asymptomatic (ACL, n=11) and non-wearers as controls (n=14). Duration of contact lens wear, Ocular Surface Disease Index (OSDI) questionnaire responses, fluorescein tear break-uptime (FBUT), and corneal confocal microscopy findings were recorded. Mean age was 25.7±8.2 years and male/female ratio was 7/33. Demographic findings were similar regarding the groups. CLD patients had a longer lens use history than ACL (median 5 vs 2 years, p<0.001). OSDI scores were higher in CLD group than ACL or controls (p<0.001, p=0.002). FBUT was significantly lowest in CLD group, compared to controls and ACL (p<0.001, p=0.039). FBUT was also lower in ACL patients compared to controls (p=0.036). There was no difference between basal epithelium cell counts between all 3 groups. Anterior stromal activated keratocyte numbers were similar between contact lens using groups but was lower in controls (p=0.005). However, dendritiform cells in the sub-basal nerve layer were higher in CLD group compared to controls but similar to ACL (p<0.001, p=0.058). Graded sub-basal nerve tortuosity was more prominent in CLD group than the ACL (p=0.014). Patients with CLD had been wearing contact lenses for longer than those without symptoms. OSDI and FBUT scores were worse in CLD patients. In contact lens discomfort patients, there were increased dendritiform cells, indicating intensified inflammatory status of the cornea. Copyright © 2017 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Metaherpetic corneal disease in a dog associated with partial limbal stem cell deficiency and neurotrophic keratitis.

PubMed

Ledbetter, Eric C; Marfurt, Carl F; Dubielzig, Richard R

2013-07-01

To describe clinical, in vivo confocal microscopic, histopathologic, and immunohistochemical features of a dog with metaherpetic corneal disease that developed subsequent to a protracted episode of canine herpesvirus-1 (CHV-1) dendritic ulcerative keratitis. A 7-year-old, spayed-female, Miniature Schnauzer was treated for bilateral CHV-1 dendritic ulcerative keratitis. Following resolution of ulcerative keratitis, sectoral peripheral superficial corneal gray opacification, vascularization, and pigmentation slowly migrated centripetally to the axial cornea of both eyes. Corneal sensitivity measured with a Cochet-Bonnet esthesiometer was dramatically and persistently reduced. In vivo corneal confocal microscopic examination revealed regions of epithelium with a conjunctival phenotype. In these areas, the surface epithelium was thin, disorganized, and composed of hyper-reflective epithelial cells. Goblet cells and Langerhans cells were frequent, and the subbasal nerve plexus was completely absent or markedly diminished. Histopathologic abnormalities in the globes were restricted to the superficial cornea and included sectoral corneal conjunctivalization, increased anterior stromal spindle cells, and vascularization. Immunohistochemical evaluation of the corneas with anti-neurotublin antibody demonstrated attenuation of the epithelial and subbasal nerve plexuses with marked stromal hyperinnervation and increased numbers of morphologically abnormal neurites. Similar to herpes simplex virus keratitis in humans, CHV-1 ulcerative keratitis may be associated with the development of chronic degenerative corneal disease in dogs. In the described dog, this chronic corneal disease included progressive corneal opacification because of partial limbal stem cell deficiency and neurotrophic keratitis. Long-term monitoring of dogs following resolution of active CHV-1 keratitis may be indicated, particularly when ulcerations persist for an extended period. © 2012 American College of Veterinary Ophthalmologists.

Recovery of the sub-basal nerve plexus and superficial nerve terminals after corneal epithelial injury in mice.

PubMed

Downie, Laura E; Naranjo Golborne, Cecilia; Chen, Merry; Ho, Ngoc; Hoac, Cam; Liyanapathirana, Dasun; Luo, Carol; Wu, Ruo Bing; Chinnery, Holly R

2018-06-01

Our aim was to compare regeneration of the sub-basal nerve plexus (SBNP) and superficial nerve terminals (SNT) following corneal epithelial injury. We also sought to compare agreement when quantifying nerve parameters using different image analysis techniques. Anesthetized, female C57BL/6 mice received central 1-mm corneal epithelial abrasions. Four-weeks post-injury, eyes were enucleated and processed for PGP9.5 to visualize the corneal nerves using wholemount immunofluorescence staining and confocal microscopy. The percentage area of the SBNP and SNT were quantified using: ImageJ automated thresholds, ImageJ manual thresholds and manual tracings in NeuronJ. Nerve sum length was quantified using NeuronJ and Imaris. Agreement between methods was considered with Bland-Altman analyses. Four-weeks post-injury, the sum length of nerve fibers in the SBNP, but not the SNT, was reduced compared with naïve eyes. In the periphery, but not central cornea, of both naïve and injured eyes, nerve fiber lengths in the SBNP and SNT were strongly correlated. For quantifying SBNP nerve axon area, all image analysis methods were highly correlated. In the SNT, there was poor correlation between manual methods and auto-thresholding, with a trend towards underestimating nerve fiber area using auto-thresholding when higher proportions of nerve fibers were present. In conclusion, four weeks after superficial corneal injury, there is differential recovery of epithelial nerve axons; SBNP sum length is reduced, however the sum length of SNTs is similar to naïve eyes. Care should be taken when selecting image analysis methods to compare nerve parameters in different depths of the corneal epithelium due to differences in background autofluorescence. Copyright © 2018 Elsevier Ltd. All rights reserved.

Comparative quantitative assessment of the human corneal sub-basal nerve plexus by in vivo confocal microscopy and histological staining.

PubMed

Kowtharapu, B S; Winter, K; Marfurt, C; Allgeier, S; Köhler, B; Hovakimyan, M; Stahnke, T; Wree, A; Stachs, O; Guthoff, R F

2017-03-01

PurposeThis study was designed to compare and contrast quantitative data of the human corneal sub-basal nerve plexus (SBP) evaluated by two different methods: in vivo confocal microscopy (IVCM), and immunohistochemical staining of ex vivo donor corneas.MethodsSeven parameters of the SBP in large-scale IVCM mosaicking images from healthy subjects were compared with the identical parameters in ex vivo donor corneas stained by β-III-tubulin immunohistochemistry. Corneal nerve fiber length (CNFL), corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD), average weighted corneal nerve fiber tortuosity (CNFTo), corneal nerve connection points (CNCP), average corneal nerve single-fiber length (CNSFL), and average weighted corneal nerve fiber thickness (CNFTh) were calculated using a dedicated, published algorithm and compared.ResultsOur experiments showed significantly higher values for CNFL (50.2 vs 21.4 mm/mm 2 ), CNFD (1358.8 vs 277.3 nerve fibers/mm 2 ), CNBD (847.6 vs 163.5 branches/mm 2 ), CNFTo (0.095 vs 0.081 μm -1 ), and CNCP (49.4 vs 21.6 connections/mm 2 ) in histologically staining specimens compared with IVCM images. In contrast, CNSFL values were higher in IVCM images than in histological specimens (32.1 vs 74.1 μm). No significant difference was observed in CNFTh (2.22 vs 2.20 μm) between the two groups.ConclusionsThe results of this study have shown that IVCM has an inherently lower resolution compared with ex vivo immunohistochemical staining of the corneal SBP and that this limitation leads to a systematic underestimation of several SBP parameters. Despite this shortcoming, IVCM is a vital clinical tool for in vivo characterization, quantitative clinical imaging, and evaluation of the human corneal SBP.

Corneal wound healing after photorefractive keratectomy: a 3-year confocal microscopy study.

PubMed Central

Erie, Jay C

2003-01-01

PURPOSE: To perform a sequential quantitative analysis of corneal wound healing after photorefractive keratectomy (PRK) by using confocal microscopy in vivo. METHODS: In a prospective, nonrandomized, comparative trial performed in an institutional setting, 24 eyes of 14 patients received PRK to correct refractive errors between -1.25 and -5.75 D. Central corneas were examined preoperatively and at 1 day, 5 days, and 1, 3, 6, 12, 24, and 36 months after PRK by using confocal microscopy. A masked observer randomly examined 3 to 6 confocal scans per eye per visit to determine epithelial and stromal thickness, keratocyte density in 5 anterior-posterior stromal layers, corneal nerve density in the subbasal region and the stroma, and corneal light backscattering (corneal haze). RESULTS: Epithelial thickness increased 21% (P < .001) by 12 months after PRK and thereafter remained unchanged to 36 months after PRK. There was no change in stromal thickness between 1 and 36 months after PRK (P = .35). The dense keratocyte population in the preoperative anterior 10% of the stroma (32,380 +/- 5,848 cells/mm3) that was partially or completely removed during photoablation was not reconstituted at 36 months in the anterior 10% of the post-PRK stroma (17,720 +/- 4,308 cells/mm3, P < .001). Subbasal nerve fiber bundle density was decreased 60% at 12 months after PRK (P < .001) before returning to densities at 24 and 36 months after PRK that were not significantly different from preoperative values (P = 1.0). Activated keratocytes and corneal haze peaked at 3 months after PRK. CONCLUSIONS: Wounding of the cornea by PRK alters the normal structure, cellularity, and innervation of the cornea for up to 36 months. PMID:14971584

Corneal Subbasal Nerve Density and Sensitivity After Pars Plana Vitrectomy Using Contact or Noncontact Wide-Angle Viewing Systems.

PubMed

Tosi, Gian Marco; Bacci, Tommaso; Tarantello, Antonio; Martone, Gianluca; Traversi, Claudio; Marigliani, Davide; Cevenini, Gabriele; Virgili, Gianni

2018-06-07

To assess corneal subbasal nerve density (SBND) and corneal sensitivity (CS) after pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD) without intraoperative 360-degree laser treatment using contact or noncontact panoramic viewing systems. This is a prospective study of 34 eyes affected by RRD, which underwent PPV using contact (18 eyes) and noncontact (16 eyes) panoramic viewing systems; 12 eyes which underwent scleral buckling, and 17 eyes which underwent cataract surgery. SBND and CS were assessed before surgery and 3 and 6 months postoperatively by in vivo confocal microscopy and Cochet-Bonnet esthesiometry. Compared with baseline values, at 6 months, SBND and CS decreased in both contact PPV (SBND preoperative value: 19.1 ± 3.7 mm/mm; SBND postoperative value: 3.5 ± 1.3 mm/mm; CS preoperative value: 5.1 ± 0.5 cm; CS postoperative value: 1.5 ± 0.4 cm) and in noncontact PPV groups (SBND preoperative value: 19.5 ± 3.8 mm/mm; SBND postoperative value: 8.7 ± 2.3 mm/mm; CS preoperative value: 5.3 ± 0.5 cm; CS postoperative value: 2.5 ± 0.7 cm) (P < 0.001 for all comparisons). SBND reduction was greater in the contact PPV group than in the noncontact PPV group (P < 0.001). By contrast, the scleral buckling and cataract surgery group values were unchanged (P > 0.1 for all comparisons). In multivariate analysis, no significant effect was found for cataract surgery associated with PPV, pseudophakia, surgical time, intraocular pressure, or for laser in horizontal sectors for PPV groups. SBND was highly correlated with CS (r = 0.93). A contact viewing system reduces SBND after PPV more than a noncontact system does.

Corneal Nerve Morphology and Tear Film Substance P in Diabetes.

PubMed

Markoulli, Maria; You, Jingjing; Kim, Juno; Duong, Carmen L; Tolentino, Jonathan B; Karras, Joshua; Lum, Edward

2017-07-01

This work aims to characterize the relationship between tear film neuropeptide substance P and the structural integrity of the sub-basal nerve plexus in diabetes. Seventeen healthy control participants and nine participants with diabetes were recruited in this cross-sectional study. Total protein content and substance P concentrations were determined in the flush tears of participants. Corneal nerve morphology was assessed by capturing the corneal sub-basal nerve plexus using the Heidelberg Retinal Tomograph II with the Rostock Corneal Module (Heidelberg Engineering GmbH, Heidelberg, Germany) in the central cornea. Corneal nerve fiber density (CNFD) was measured using ACCMetrics (M.A. Dabbah, Imaging Science and Biomedical Engineering, Manchester, UK) on eight captured images. Comparisons between groups were made using independent samples t-tests. Correlations between parameters were analyzed using Pearson's correlations. Substance P concentrations were significantly higher in the tears of the control group compared to participants with diabetes (4150 ± 4752 and 1473 ± 1671 pg/mL, respectively, P = .047). There was no significant difference in total protein content between the groups (3.4 ± 1.8 and 2.6 ± 1.7 mg/mL in the control and diabetes groups, respectively, P = .262). CNFD was significantly lower in the participants with diabetes compared to the control group (16.1 ± 5.7 and 21.5 ± 7.0 mm/mm, respectively, P = .041). There was a moderate correlation between substance P and CNFD (r = 0.48, P = .01). Substance P is expressed at a significantly lower level in the tears of people with diabetes compared with healthy controls. The positive correlation between substance P and corneal nerve density indicates that substance P may be a potential biomarker for corneal nerve health.

A new species of Simulium (Simulium) (Diptera: Simuliidae) from Genting Highlands, Malaysia.

PubMed

Ya'cob, Zubaidah; Takaoka, Hiroyuki; Low, Van Lun; Sofian-Azirun, Mohd

2018-06-01

Simulium (Simulium) rasuli sp. nov. is described from two females collected by a Malaise trap in Genting Highlands, Peninsular Malaysia. This new species is placed in the Simulium christophersi species-group of the subgenus Simulium. The female of this new specie is characterized by the scutum with three longitudinal vittae, dark legs, claw with a small subbasal tooth, and ovipositor valve triangular with its inner margin nearly straight. This new species is distinguished in the female from all the six named species of the species-group by the entirely brownish-black femora and tibiae. Copyright © 2018 Elsevier B.V. All rights reserved.

[Morphological characteristics of cornea in patients with vernal keratoconjunctivitis by in vivo laser scanning confocal microscopy].

PubMed

Le, Qi-hua; Hong, Jia-xu; Zhu, Wen-qing; Sun, Xing-huai; Xu, Jian-jiang

2011-05-01

To explore the morphological characteristics on cornea in patients with vernal keratoconjunctivitis (VKC) by the application of in vivo laser scanning confocal microscopy (LSCM). The experimental design was retrospective observation case series (case control study). Twenty-six patients, each diagnosed as bilateral VKC, were enrolled in the study, among which 13 were tarsal form, 5 were bulbar form and the rest were mixed form. Nine patients had the clinical course less than one year, eight subjects longer than three years, and the rest between them. Another twenty-six healthy volunteers with matching age and gender were selected as normal control. All participants had their right eyes examined with the in vivo confocal microscopy (HRT II/RCM). Central cornea and superior peripheral cornea were chosen as the examination points. The images were recorded automatically and cellular density of each layer was analyzed by installed software. Software ImageJ was utilized to analyze the density, diameter, branch number and tortuosity of subbasal nerve fiber in VKC patients. Independent t test was performed to assess the differences on cellular density between VKC patients and normal control, as well as those between central and peripheral cornea in VKC patients. Fisher chi-square test was used to compare the infiltration rate of Langerhans cells in corneal epithelium between VKC patients and controls. ANOVA was applied to assess the differences in cellular density among three subtypes, as well as among different duration of VKC. Independent t-test and chi-square test were applied to analyze the parameters of subbasal nerve fiber. The morphological changes in cornea included the absence of superficial hyperreflective polygonal epithelial cells, infiltration of Langerhans cells in and(or) underneath corneal epithelium and activation of keratocytes in anterior stroma. Corneal epithelium conjunctivalization and stromal neovascularization could be identified in patients with corneal neovascular epithelium. Longitudinal or oblique dark striae could be found in the posterior stroma in patients with complicated keratoconus. The density of epithelial cells at central and peripheral cornea in healthy controls were (6033.1 ± 998.7) cells/mm(2) and (6098.4 ± 298.3) cells/mm(2), while that in VKC patients were (5972.2 ± 1148.2) cells/mm(2) and (6178.5 ± 318.9) cells/mm(2) respectively, the differences being no statistical significant between them (t = 1.191, 1.011; P = 0.238, 0.318). However, it's found in VKC patients that cellular density at peripheral cornea was significantly higher than that at central area (t = 2.249, P = 0.03). The density of anterior stromal cells at central and peripheral cornea in healthy controls was (1001.4 ± 125.3) cells/mm(2) and (924.6 ± 201.4) cells/mm(2), while that in VKC patients was (1184.5 ± 115.3) cells/mm(2) and (1101.4 ± 151.1) cells/mm(2), the difference bearing no statistical significance (t = 6.617, 3.439; P = 0.001). The density of posterior stromal cells in normal subjects and VKC patients was (537.7 ± 42.6) cells/mm(2) and (548.7 ± 79.8) cells/mm(2), that of endothelial cells was (2985.7 ± 401.2) cells/mm(2) and (3021.5 ± 383.3) cells/mm(2), respectively, neither difference had statistical significance (t = 0.174, 1.112; P = 0.864, 0.282). Langerhans cell infiltration could be identified in 61.5% (16 cases) VKC patients, which was significantly higher than normal control (2 cases, 7.7%) (χ(2) = 12.49, P = 0.001). Furthermore, much intense Langerhans cells infiltration was found in bulbar form and mix form than tarsal form. (t = 6.617, P = 0.001). The density and diameter of subbasal nerve fiber in VKC patients decreased significantly than those in normal subjects, whereas the tortuosity increased significantly. The morphological changes of cornea in VKC patients mainly involve corneal epithelium, subbasal nerve fiber and anterior stroma. In vivo LSCM is helpful in discriminating the subtypes of VKC.

The contribution of hydrothermally altered ocean crust to the mantle halogen and noble gas cycles

NASA Astrophysics Data System (ADS)

Chavrit, Déborah; Burgess, Ray; Sumino, Hirochika; Teagle, Damon A. H.; Droop, Giles; Shimizu, Aya; Ballentine, Chris J.

2016-06-01

Recent studies suggest that seawater-derived noble gases and halogens are recycled into the deep mantle by the subduction of oceanic crust. To understand the processes controlling the availability of halogens and noble gases for subduction, we determined the noble gas elemental and isotopic ratios and halogen (Cl, Br, I) concentrations in 28 igneous samples from the altered oceanic crust (AOC) from 5 ODP sites in the Eastern and Western Pacific Ocean. Crushing followed by heating experiments enabled determination of noble gases and halogens in fluid inclusions and mineral phases respectively. Except for He and Ar, Ne, Kr and Xe isotopic ratios were all air-like suggesting that primary MORB signatures have been completely overprinted by air and/or seawater interaction. In contrast, 3He/4He ratios obtained by crushing indicate that a mantle helium component is still preserved, and 40Ar/36Ar values are affected by radiogenic decay in the mineral phases. The 130Xe/36Ar and 84Kr/36Ar ratios are respectively up to 15 times and 5 times higher than those of seawater and the highest ratios are found in samples affected by low temperature alteration (shallower than 800-900 m sub-basement). We consider three possible processes: (i) adsorption onto the clays present in the samples; (ii) fluid inclusions with a marine pore fluid composition; and (iii) fractionation of seawater through phase separation caused by boiling. Ninety percent of the Cl, Br and I were released during the heating experiments, showing that halogens are dominantly held in mineral phases prior to subduction. I/Cl ratios vary by 4 orders of magnitude, from 3 × 10-6 to 2 × 10-2. The mean Br/Cl ratio is 30% lower than in MORB and seawater. I/Cl ratios lower than MORB values are attributed to Cl-rich amphibole formation caused by hydrothermal alteration at depths greater than 800-900 m sub-basement together with different extents of I loss during low and high temperature alteration. At shallower depths, I/Cl ratios higher than MORB values can be explained by the addition of organic-rich sediments or the presence of organic detritus, both known to efficiently sequester I. Concentrations of 36Ar of the pre-subducting materials are sufficient to account for the 36Ar and composition of the mantle in the context of existing subduction-flux models. We find the Cl subduction flux of the oceanic crust to be about three times higher than the previous estimates and that sufficient Cl and Br can potentially be delivered by subduction over the last 3 Ga to account for mantle source compositions.

Autologous Serum Tears for Treatment of Photoallodynia in Patients with Corneal Neuropathy: Efficacy and Evaluation with In Vivo Confocal Microscopy.

PubMed

Aggarwal, Shruti; Kheirkhah, Ahmad; Cavalcanti, Bernardo M; Cruzat, Andrea; Colon, Clara; Brown, Emma; Borsook, David; Prüss, Harald; Hamrah, Pedram

2015-07-01

Patients suffering from corneal neuropathy may present with photoallodynia; i.e., increased light sensitivity, frequently with a normal slit-lamp examination. This study aimed to evaluate the efficacy of autologous serum tears (AST) for treatment of severe photoallodynia in corneal neuropathy and to correlate clinical findings with corneal subbasal nerve alterations by in vivo confocal microscopy (IVCM). Retrospective case control study with 16 patients with neuropathy-induced severe photoallodynia compared to 16 normal controls. Symptom severity, clinical examination and bilateral corneal IVCM scans were recorded. All patients suffered from extreme photoallodynia (8.8±1.1) with no concurrent ocular surface disease. Subbasal nerves were significantly decreased at baseline in patients compared to controls; total nerve length (9208±1264 vs 24714±1056 μm/mm(2); P<.0001) and total nerve number (9.6±1.4 vs 28.6±2.0; P<.0001), respectively. Morphologically, significantly increased reflectivity (2.9±0.2 vs 1.8±0.1; P<.0001), beading (in 93.7%), and neuromas (in 62.5%) were seen. AST (3.6±2.1 months) resulted in significantly decreased symptom severity (1.6±1.7; P=.02). IVCM demonstrated significantly improved nerve parameters (P<.005), total nerve length (15451±1595 μm/mm(2)), number (13.9±2.1), and reflectivity (1.9±0.1). Beading and neuromas were seen in only 56.2% and 7.6% of patients. Patients with corneal neuropathy-induced photoallodynia show profound alterations in corneal nerves. AST restores nerve topography through nerve regeneration, and this correlated with improvement in patient-reported photoallodynia. The data support the notion that corneal nerve damage results in alterations in afferent trigeminal pathways to produce photoallodynia. Copyright © 2015 Elsevier Inc. All rights reserved.

Description of Alloretochus sigillatus new species with comments and new distributional records for Alloretochus peruanicus (Ephemeroptera, Caenidae, Brachycercinae).

PubMed

Molineri, C

2014-06-19

Alloretochus sigillatus sp. nov. is described from adults of both sexes and eggs from Bolivia and Ecuador. Diagnostic characters of this species include: large body size, ratio pedicel/scape 1.75, presence of posteromedian projection on metanotum, characteristic blackish marks on abdominal terga, presence of vestiges of posterolateral projections on abdomen segments IV-VI, male subgenital plate broadly emarginated posteriorly, ratios forceps length/subbasal width 8.9, female sternum IX produced distally reaching apex of segment X, tapering distally with rounded apex, egg with 4 costae in lateral half. Additional characters for all stages and SEM photographs of eggs are provided for Alloretochus peruanicus, with new records of its presence in Argentina, Bolivia, Peru and Colombia.

In vivo high resolution human corneal imaging using full-field optical coherence tomography.

PubMed

Mazlin, Viacheslav; Xiao, Peng; Dalimier, Eugénie; Grieve, Kate; Irsch, Kristina; Sahel, José-Alain; Fink, Mathias; Boccara, A Claude

2018-02-01

We present the first full-field optical coherence tomography (FFOCT) device capable of in vivo imaging of the human cornea. We obtained images of the epithelial structures, Bowman's layer, sub-basal nerve plexus (SNP), anterior and posterior stromal keratocytes, stromal nerves, Descemet's membrane and endothelial cells with visible nuclei. Images were acquired with a high lateral resolution of 1.7 µm and relatively large field-of-view of 1.26 mm x 1.26 mm - a combination, which, to the best of our knowledge, has not been possible with other in vivo human eye imaging methods. The latter together with a contactless operation, make FFOCT a promising candidate for becoming a new tool in ophthalmic diagnostics.

Geochemical characterization and leaching behavior of slags: by-product materials from an old lead smelter in Chihuahua, Mexico

NASA Astrophysics Data System (ADS)

Espejel-Garcia, D.; Wenglas-Lara, G.; Villalobos-Aragon, A.; Espejel-Garcia, V. V.

2012-12-01

Steel slags are stored in piles or stocks around or near the smelter site. Currently, there is an increasing interest in the use of waste materials, especially in the construction industry, to replace natural aggregates, help the environment and reduce the costs. Slags are being used widely as road ballast, road base or sub-base material, sandblasting agents or cement additives, but normally contain high concentrations of potentially toxic metals. Although these metals are associated with glass, silicate and oxide minerals, with slow solubilities in water, a characterization of the leaching behavior is essential in environmental evaluation for reuse scenarios. The state of Chihuahua is located in northern Mexico, and mining has been an important economic activity since the 18th century. In the early 1900's, a lead smelter operated in Avalos, Chihuahua (in the southern surroundings of Chihuahua city), and left considerable slag piles after their closure in the 1980's. In this study, this material has been geochemically analyzed to identify the metals contained in it, and used in "tank tests" experiments, to assess its leaching behavior. The slags from Chihuahua contain Pb (0.5 - 4 wt.%), Zn (15-35 wt.%) and As (0.6 wt.%) in different minerals such as hardystonite (Ca2ZnSi2O7), melanotekite (Pb2Fe3+3O2Si2O7), kentrolite (Pb2Mn2Si2O9) and sphalerite (ZnS) or trapped in the glass. Major elements are present in phases such as monticellite (CaMgSiO4), kirschsteinite (CaFe2+SiO4), hedenbergite (CaFeSi2O6), babingtonite (Fe2Si3O9), magnetite (Fe3O4), and calcite (CaCO3). The leaching experiments were performed for 6, 24, 168 and 360 hours in mixtures of 30 and 50% of slags with natural road base material using distilled water at a pH 5 and 8 to recreate acidic and alkaline waters. The amounts of leached Pb ranges from 0.1 to 0.5 ppm, Zn from 0.1 to 0.6 ppm, As from 0 to 0.09 ppm, and Ca from 40 to 180 ppm, being the acidic experiments the ones that leached out the highest amounts of metals. Based on the results of analyses and experiments, it is recommended to use the waste material (slags) as aggregates in road construction, but only as minor constituent (<30%) in base materials.

Inflammation and the nervous system: the connection in the cornea in patients with infectious keratitis.

PubMed

Cruzat, Andrea; Witkin, Deborah; Baniasadi, Neda; Zheng, Lixin; Ciolino, Joseph B; Jurkunas, Ula V; Chodosh, James; Pavan-Langston, Deborah; Dana, Reza; Hamrah, Pedram

2011-07-11

To study the density and morphologic characteristics of epithelial dendritic cells, as correlated to subbasal corneal nerve alterations in acute infectious keratitis (IK) by in vivo confocal microscopy (IVCM). IVCM of the central cornea was performed prospectively in 53 eyes with acute bacterial (n = 23), fungal (n = 13), and Acanthamoeba (n = 17) keratitis, and in 20 normal eyes, by using laser in vivo confocal microscopy. Density and morphology of dendritic-shaped cells (DCs) of the central cornea, corneal nerve density, nerve numbers, branching, and tortuosity were assessed and correlated. It should be noted that due to the "in vivo" nature of the study, the exact identity of these DCs cannot be specified, as they could be monocytes or tissue macrophages, but most likely dendritic cells. IVCM revealed the presence of central corneal DCs in all patients and controls. The mean DC density was significantly higher in patients with bacterial (441.1 ± 320.5 cells/mm(2); P < 0.0001), fungal (608.9 ± 812.5 cells/mm(2); P < 0.0001), and Acanthamoeba keratitis (1000.2 ± 1090.3 cells/mm(2); P < 0.0001) compared with controls (49.3 ± 39.6 cells/mm(2)). DCs had an increased size and dendrites in patients with IK. Corneal nerves were significantly reduced in eyes with IK compared with controls across all subgroups, including nerve density (674.2 ± 976.1 vs. 3913.9 ± 507.4 μm/frame), total nerve numbers (2.7 ± 3.9 vs. 20.2 ± 3.3), main trunks (1.5 ± 2.2 vs. 6.9 ± 1.1), and branching (1.2 ± 2.0 vs. 13.5 ± 3.1; P < 0.0001). A strong association between the diminishment of corneal nerves and the increase of DC density was observed (r = -0.44; P < 0.0005). IVCM reveals an increased density and morphologic changes of central epithelial DCs in infectious keratitis. There is a strong and significant correlation between the increase in DC numbers and the decreased subbasal corneal nerves, suggesting a potential interaction between the immune and nervous system in the cornea.

Diabetic Foot Syndrome and Corneal Subbasal Nerve Plexus Changes in Congolese Patients with Type 2 Diabetes

PubMed Central

Schober, Hans-Christof; Stachs, Oliver; Baltrusch, Simone; Bambi, Marie Therese; Kilangalanga, Janvier; Winter, Karsten; Kundt, Guenther; Guthoff, Rudolf F.

2015-01-01

Background To study the severity of diabetic neuropathy, diabetic retinopathy and grades of diabetic foot syndrome for correlations with corneal subbasal nerve plexus (SBP) changes in Congolese patients with type 2 diabetes. Methodology/Principal Findings Twenty-eight type 2 diabetes patients with diabetes-related foot ulceration were recruited in a diabetic care unit in Kinshasa, Democratic Republic of Congo. Corneal SBP was investigated by confocal laser-scanning microscopy to analyse nerve fibre density (NFD) [µm/ µm²], number of branches [n] and number of connectivity points [n]. Foot ulceration was graded using the Wagner ulcer classification. Corneal sensitivity (Cochet-Bonnet), Neuropathy Symptom Score (NSS), Neuropathy Disability Score (NDS), ankle-brachial index (ABI) and ophthalmological status were evaluated. Foot ulceration was ranked as mild (Wagner 0-1: 13 patients/46.4%), moderate (Wagner 2-3: 10 patients/35.7%) and severe (Wagner 4-5: 5 patients/17.9%). The correlation between Wagner Score and NFD (p=0.017, r = - 0,454), NDS and NFD (p=0,039, r = - 0.400) as well as Wagner Score and HbA1c (p=0,007, r = - 0.477) was stated. Significant differences in confocal SBP parameters were observed between Wagner 0-1 and Wagner 4 5 (number of branches (p=0.012), number of connectivity points (p=0.001), nerve fibre density (p=0.033)) and ABI (p=0.030), and between Wagner 2-3 and Wagner 4-5 (number of branches (p=0.003), number of connectivity points (p=0.005) and nerve fibre density (p=0.014)). Differences in NDS (p=0.001) and corneal sensation (p=0.032) were significant between Wagner 0-1 and Wagner 2-3. Patients with diabetic retinopathy had significantly longer diabetes duration (p=0.03) and higher NDS (p=0.01), but showed no differences in SBP morphology or corneal sensation. Conclusions/Significance While confirming the diabetic aetiology of foot ulceration due to medial arterial calcification, this study indicates that the grade of diabetic foot syndrome correlates with corneal SBP changes and corneal sensation in patients in sub-Saharan Africa. PMID:25811186

Feasibility of Using Unbound Mixed Recycled Aggregates from CDW over Expansive Clay Subgrade in Unpaved Rural Roads

PubMed Central

Del Rey, Isaac; Ayuso, Jesús; Galvín, Adela P.; Jiménez, José R.; Barbudo, Auxi

2016-01-01

Social awareness aims to increase practical skills, such as sustainable development, which seeks to increase the use of different types of waste in construction activities. Although insufficient attention is sometimes given to these actions, it is essential to spread information regarding new studies in the field of waste recycling, which encourages and promotes waste use. Reusing and recycling construction waste in the creation of buildings and infrastructure are fundamental strategies to achieving sustainability in the construction and engineering sectors. In this context, the concept of waste would no longer exist, as waste would become a material resource. Therefore, this study analyses the behaviours of two unbound mixed recycled aggregates (MRA) in the structural layers of an unpaved rural road with low traffic (category T43). The sections were built on inappropriate soil (A-7-6) with a high degree of free swelling. The experimental road consisted of three sections: the first was made with natural aggregates (NA) that were used as a control, the second was composed of MRA in the subbase and NA in the base, and the third section was completely composed of MRA. The materials were characterised in the laboratory. The behaviours of the structural layers in the experimental road were determined by controlling compaction (“in situ” density and moisture) and measuring the deflections and load capacity (deflectometer) during the 18 months after construction. The results show that the sections made with recycled aggregates meet the technical specifications required by General Technical Specifications for Road and Bridge Works (PG-3). Therefore, the water-soluble sulphate content and Los Angeles abrasion coefficient limits can be increased for recycled aggregates without compromising the quality of this type of road with low traffic. To the best of our knowledge, this is the first study regarding the use of unbound MRA made from construction and demolition waste (CDW) in the construction of an unpaved rural road with low traffic on an expansive clay subgrade. PMID:28774053

A Review of Centrifugal Testing of Gasoline Contamination and Remediation

PubMed Central

Meegoda, Jay N.; Hu, Liming

2011-01-01

Leaking underground storage tanks (USTs) containing gasoline represent a significant public health hazard. Virtually undetectable to the UST owner, gasoline leaks can contaminate groundwater supplies. In order to develop remediation plans one must know the extent of gasoline contamination. Centrifugal simulations showed that in silty and sandy soils gasoline moved due to the physical process of advection and was retained as a pool of free products above the water table. However, in clayey soils there was a limited leak with lateral spreading and without pooling of free products above the water table. Amount leaked depends on both the type of soil underneath the USTs and the amount of corrosion. The soil vapor extraction (SVE) technology seems to be an effective method to remove contaminants from above the water table in contaminated sites. In-situ air sparging (IAS) is a groundwater remediation technology for contamination below the water table, which involves the injection of air under pressure into a well installed into the saturated zone. However, current state of the art is not adequate to develop a design guide for site implementation. New information is being currently generated by both centrifugal tests as well as theoretical models to develop a design guide for IAS. The petroleum contaminated soils excavated from leaking UST sites can be used for construction of highway pavements, specifically as sub-base material or blended and used as hot or cold mix asphalt concrete. Cost analysis shows that 5% petroleum contaminated soils is included in hot or cold mix asphalt concrete can save US$5.00 production cost per ton of asphalt produced. PMID:21909320

A review of centrifugal testing of gasoline contamination and remediation.

PubMed

Meegoda, Jay N; Hu, Liming

2011-08-01

Leaking underground storage tanks (USTs) containing gasoline represent a significant public health hazard. Virtually undetectable to the UST owner, gasoline leaks can contaminate groundwater supplies. In order to develop remediation plans one must know the extent of gasoline contamination. Centrifugal simulations showed that in silty and sandy soils gasoline moved due to the physical process of advection and was retained as a pool of free products above the water table. However, in clayey soils there was a limited leak with lateral spreading and without pooling of free products above the water table. Amount leaked depends on both the type of soil underneath the USTs and the amount of corrosion. The soil vapor extraction (SVE) technology seems to be an effective method to remove contaminants from above the water table in contaminated sites. In-situ air sparging (IAS) is a groundwater remediation technology for contamination below the water table, which involves the injection of air under pressure into a well installed into the saturated zone. However, current state of the art is not adequate to develop a design guide for site implementation. New information is being currently generated by both centrifugal tests as well as theoretical models to develop a design guide for IAS. The petroleum contaminated soils excavated from leaking UST sites can be used for construction of highway pavements, specifically as sub-base material or blended and used as hot or cold mix asphalt concrete. Cost analysis shows that 5% petroleum contaminated soils is included in hot or cold mix asphalt concrete can save US$5.00 production cost per ton of asphalt produced.

Inflammation and the Nervous System: The Connection in the Cornea in Patients with Infectious Keratitis

PubMed Central

Cruzat, Andrea; Witkin, Deborah; Baniasadi, Neda; Zheng, Lixin; Ciolino, Joseph B.; Jurkunas, Ula V.; Chodosh, James; Pavan-Langston, Deborah; Dana, Reza

2011-01-01

Purpose. To study the density and morphologic characteristics of epithelial dendritic cells, as correlated to subbasal corneal nerve alterations in acute infectious keratitis (IK) by in vivo confocal microscopy (IVCM). Methods. IVCM of the central cornea was performed prospectively in 53 eyes with acute bacterial (n = 23), fungal (n = 13), and Acanthamoeba (n = 17) keratitis, and in 20 normal eyes, by using laser in vivo confocal microscopy. Density and morphology of dendritic-shaped cells (DCs) of the central cornea, corneal nerve density, nerve numbers, branching, and tortuosity were assessed and correlated. It should be noted that due to the “in vivo” nature of the study, the exact identity of these DCs cannot be specified, as they could be monocytes or tissue macrophages, but most likely dendritic cells. Results. IVCM revealed the presence of central corneal DCs in all patients and controls. The mean DC density was significantly higher in patients with bacterial (441.1 ± 320.5 cells/mm2; P < 0.0001), fungal (608.9 ± 812.5 cells/mm2; P < 0.0001), and Acanthamoeba keratitis (1000.2 ± 1090.3 cells/mm2; P < 0.0001) compared with controls (49.3 ± 39.6 cells/mm2). DCs had an increased size and dendrites in patients with IK. Corneal nerves were significantly reduced in eyes with IK compared with controls across all subgroups, including nerve density (674.2 ± 976.1 vs. 3913.9 ± 507.4 μm/frame), total nerve numbers (2.7 ± 3.9 vs. 20.2 ± 3.3), main trunks (1.5 ± 2.2 vs. 6.9 ± 1.1), and branching (1.2 ± 2.0 vs. 13.5 ± 3.1; P < 0.0001). A strong association between the diminishment of corneal nerves and the increase of DC density was observed (r = −0.44; P < 0.0005). Conclusions. IVCM reveals an increased density and morphologic changes of central epithelial DCs in infectious keratitis. There is a strong and significant correlation between the increase in DC numbers and the decreased subbasal corneal nerves, suggesting a potential interaction between the immune and nervous system in the cornea. PMID:21460259

A comprehensive numerical analysis of the hydraulic behavior of a permeable pavement

NASA Astrophysics Data System (ADS)

Brunetti, Giuseppe; Šimůnek, Jiří; Piro, Patrizia

2016-09-01

The increasing frequency of flooding events in urban catchments related to an increase in impervious surfaces highlights the inadequacy of traditional urban drainage systems. Low Impact Development (LID) techniques have proven to be a viable and effective alternative by reducing stormwater runoff and increasing the infiltration and evapotranspiration capacity of urban areas. However, the lack of adequate modeling tools represents a barrier in designing and constructing such systems. This paper investigates the suitability of a mechanistic model, HYDRUS-1D, to correctly describe the hydraulic behavior of permeable pavement installed at the University of Calabria. Two different scenarios of describing the hydraulic behavior of the permeable pavement system were analyzed: the first one uses a single-porosity model for all layers of the permeable pavement; the second one uses a dual-porosity model for the base and sub-base layers. Measured and modeled month-long hydrographs were compared using the Nash-Sutcliffe efficiency (NSE) index. A Global Sensitivity Analysis (GSA) followed by a Monte Carlo filtering highlighted the influence of the wear layer on the hydraulic behavior of the pavement and identified the ranges of parameters generating behavioral solutions. Reduced ranges were then used in the calibration procedure conducted with the metaheuristic Particle swarm optimization (PSO) algorithm for the estimation of hydraulic parameters. The best fit value for the first scenario was NSE = 0.43; for the second scenario, it was NSE = 0.81, indicating that the dual-porosity approach is more appropriate for describing the variably-saturated flow in the base and sub-base layers. Estimated parameters were validated using an independent, month-long set of measurements, resulting in NSE values of 0.43 and 0.86 for the first and second scenarios, respectively. The improvement in correspondence between measured and modeled hydrographs confirmed the reliability of the combination of GSA and PSO in dealing with highly dimensional optimization problems. Obtained results have demonstrated that PSO, due to its easiness of implementation and effectiveness, can represent a new and viable alternative to traditional optimization algorithms for the inverse estimation of unsaturated hydraulic properties. Finally, the results confirmed the suitability and the accuracy of HYDRUS-1D in correctly describing the hydraulic behavior of permeable pavements.

Organic Matter and δ 13C Throughout a Sub-Basement Red Soil Unit in Hole 1206A Cored During Ocean Drilling Program Leg 197 (Koko Seamount): First Results

NASA Astrophysics Data System (ADS)

Bonaccorsi, R.

2002-12-01

Although the discovery of deep red-brown paleosols during Deep Sea Drilling Project (DSDP) and Ocean Drilling Program (ODP) legs dates back to the 80's [1-3], the potential for preservation of organic matter in these igneous-derived silty-claystone units has been overlooked, and depositional settings have been inferred from only petrologic observations. This work aims to present the first geochemical (TOC, N total) and carbon isotope (δ 13C) data of a metre-thick paleosol Unit (Core 197-1206A-40R-1, 101 cm, to 40R-3, 77 cm; Subunits 18A and 18B, 307.5 to 309.9 mbsf) cored at Site 1206 (Koko Seamount) during ODP Leg 197 (Emperor Seamounts, north Pacific transect)[4-5]. Study of the sources and variation with depth of organic matter in sub-basement Fe-oxide-rich paleosol units from Leg 197 contributes to understanding the palaeoenvironmental history of the Emperor Seamounts prior to, during and after their burial and subsidence (ca. >48 to 56 Ma). Furthermore, preserved organic traces in such an isolated deep Earth system make them a useful test bed for future deep Earth's biosphere-relevant investigations [5-6]. Throughout Core 197-1206A-40R soil unit, Corg (TOC = 0.03-0.07%; 0.049 \\pm 0.011, n=7) and total nitrogen (Ntot = 0.00-0.06 %) are within the range (TOC = 0.05% to 0.12%, n=38) measured for the sub-basement paleosoil/rock units found at Site 1205 [4-5]. The δ 13C (bulk organic matter) values for the paleosol regularly decrease downcore from -25.3 \\permil (Sample 197-1206-40R-1, 103-104, at 307.54 mbsf) to -26.2 \\permil (Sample 197-1206A-40R-2, 130-131; at 308.92 mbsf) in contrast to an exposed Hawaiian oxisol sample (e.g., Ohau-2, 100-105 cm-depth with δ 13C = -23.0 \\permil). Typical uncertainties for these measurements were <\\pm 0.1\\permil to <\\pm 0.3\\permil. It is proposed that δ 13C org values of ca. -25 \\permil to ca. -26 \\permil support a terrestrial, rather than marine source [e.g., 7-8] of organics preserved in the paleosol interbed from Core 197-1206A-40R. Thus, providing additional evidence for red claystone units as soil horizons subaerially formed on the top of Koko and Nintoku Seamounts, and buried by erupted lava flowing in a nearshore environment [1,3-4]. Also, since some bacterial-induced changes in the pristine (?humic) organic compounds may have occurred over time [5], the δ 13C org values could reflect mixing between primary terrestrial/lacustrine and/or primary/secondary (bacterial) organic matter. However, δ 13C alone is inadequate at distinguishing among different carbon sources (i.e., lacustrine algae and C3 land plants, [e.g., 8)]; further use of Isotope Ratio Mass Spectrometry (EA-IRMS) for measuring δ 15N tot in these interesting paleosols is underway. {References: [1] Karpoff, A.M., 1980. Init. Repts. DSDP, 55: Washington, 707-711; [2]Shipboard Scientific Party, 1993a Site 871, Proc. ODP, Init. Repts. 144, 41-103; [3] Holmes, M.A., 1995. Proc. ODP, Scientific Results, v. 144: 381-398; [4] Shipboard Scientific Party, 2002, Proc. ODP, Init. Repts. 197: College Station, TX; [5] Bonaccorsi, R., et al. 2002, Abstract, IAU 2002 Bioastronomy Symposium; [6] Furnes, H., et al., 2001, Abstract, GSA 2001 Annual Meeting; [7] Meyers, P.A., 1994. Chemical Geology, 144, 289-302; [8] Meyers, P.A., 1997. Org. Geochem., 27, 5/6:213-259

Leaching behaviour of incineration bottom ash in a reuse scenario: 12years-field data vs. lab test results.

PubMed

Di Gianfilippo, Martina; Hyks, Jiri; Verginelli, Iason; Costa, Giulia; Hjelmar, Ole; Lombardi, Francesco

2018-03-01

Several types of standardized laboratory leaching tests have been developed during the past few decades to evaluate the leaching behaviour of waste materials as a function of different parameters, such as the pH of the eluate and the liquid to solid ratio. However, the link between the results of these tests and leaching data collected from the field (e.g. in disposal or reuse scenarios) is not always straightforward. In this work, we compare data obtained from an on-going large scale field trial, in which municipal solid waste incineration bottom ash is being tested as road sub-base material, with the results obtained from percolation column and pH-dependence laboratory leaching tests carried out on the bottom ash at the beginning of the test. The comparisons reported in this paper show that for soluble substances (e.g. Cl, K and SO 4 ), percolation column tests can provide a good indication of the release expected in the field with deviations usually within a factor of 3. For metals characterized by a solubility-controlled release, i.e. that depends more on eluate pH than the liquid to solid ratio applied, the results of pH-dependence tests describe more accurately the eluate concentration trends observed in the field with deviations that in most cases (around 80%) are within one order of magnitude (see e.g. Al and Cd). The differences between field and lab-scale data might be in part ascribed to the occurrence in the field of weathering reactions (e.g. carbonation) but also to microbial decomposition of organic matter that modifying leachate pH affect the solubility of several constituents (e.g. Ca, Ba and Cr). Besides, weathering reactions can result in enhanced adsorption of fulvic acids to iron/aluminum (hydr)oxides, leading to a decrease in the leaching of fulvic acids and hence of elements such as Cu, Ni and Pb that strongly depend on DOC leaching. Overall, this comparison shows that percolation column tests and pH-dependence tests can represent a reliable screening tool to derive data that could be employed in risk-based analysis or life cycle assessment (LCA) frameworks for evaluating potential environmental impacts deriving from specific disposal/reuse options for waste materials. Copyright © 2017 Elsevier Ltd. All rights reserved.

Unsaturated hydraulic behaviour of a permeable pavement: Laboratory investigation and numerical analysis by using the HYDRUS-2D model

NASA Astrophysics Data System (ADS)

Turco, Michele; Kodešová, Radka; Brunetti, Giuseppe; Nikodem, Antonín; Fér, Miroslav; Piro, Patrizia

2017-11-01

An adequate hydrological description of water flow in permeable pavement systems relies heavily on the knowledge of the unsaturated hydraulic properties of the construction materials. Although several modeling tools and many laboratory methods already exist in the literature to determine the hydraulic properties of soils, the importance of an accurate materials hydraulic description of the permeable pavement system, is increasingly recognized in the fields of urban hydrology. Thus, the aim of this study is to propose techniques/procedures on how to interpret water flow through the construction system using the HYDRUS model. The overall analysis includes experimental and mathematical procedures for model calibration and validation to assess the suitability of the HYDRUS-2D model to interpret the hydraulic behaviour of a lab-scale permeable pavement system. The system consists of three porous materials: a wear layer of porous concrete blocks, a bedding layers of fine gravel, and a sub-base layer of coarse gravel. The water regime in this system, i.e. outflow at the bottom and water contents in the middle of the bedding layer, was monitored during ten irrigation events of various durations and intensities. The hydraulic properties of porous concrete blocks and fine gravel described by the van Genuchten functions were measured using the clay tank and the multistep outflow experiments, respectively. Coarse gravel properties were set at literature values. In addition, some of the parameters (Ks of the concrete blocks layer, and α, n and Ks of the bedding layer) were optimized with the HYDRUS-2D model from water fluxes and soil water contents measured during irrigation events. The measured and modeled hydrographs were compared using the Nash-Sutcliffe efficiency (NSE) index (varied between 0.95 and 0.99) while the coefficient of determination R2 was used to assess the measured water content versus the modelled water content in the bedding layer (R2 = 0.81 ÷ 0.87) . The parameters were validated using the remaining sets of measurements resulting in NSE values greater than 0.90 (0.91 ÷ 0.99) and R2 between 0.63 and 0.91. Results have confirmed the applicability of HYDRUS-2D to describe correctly the hydraulic behaviour of the lab-scale system.

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

Alan E. Bland

Montana-Dakota Utilities (MDU) and Western Research Institute (WRI) have been developing flowable fill materials formulated using ash from the Montana-Dakota Utilities R. M. Heskett Station in Mandan, North Dakota. MDU and WRI have partnered with the U.S. Department of Energy (DOE) and the North Dakota Industrial Commission (NDIC) to further the development of these materials for lignite-fired fluidized-bed combustion (FBC) facilities. The MDU controlled density fill (CDF) appears to be a viable engineering material and environmentally safe. WRI is pursuing the commercialization of the technology under the trademark Ready-Fill{trademark}. The project objectives were to: (1) assess the market in themore » Bismarck-Mandan area; (2) evaluate the geotechnical properties and environmental compatibility; and (3) construct and monitor demonstrations of the various grades of flowable fill products in full-scale demonstrations. The scope of initial phase of work entailed the following: Task I--Assess Market for MDU Flowable Fill Products; Task II--Assess Geotechnical and Environmental Properties of MDU Flowable Fill Products; and Task III--Demonstrate and Monitor MDU Flowable Fill Products in Field-Scale Demonstrations. The results of these testing and demonstration activities proved the following: (1) The market assessment indicated that a market exists in the Bismarck-Mandan area for structural construction applications, such as sub-bases for residential and commercial businesses, and excavatable fill applications, such as gas line and utility trench filling. (2) The cost of the MDU flowable fill product must be lower than the current $35-$45/cubic yard price if it is to become a common construction material. Formulations using MDU ash and lower-cost sand alternatives offer that opportunity. An estimated market of 10,000 cubic yards of MDU flowable fill products could be realized if prices could be made competitive. (3) The geotechnical properties of the MDU ash-based flowable fill can be modified to meet the needs of a range of applications from structural fill applications to excavatable applications, such as utility trench fill. (4) Environmental assessments using standard testing indicate that the environmental properties of the fill materials are compatible with numerous construction applications and do not pose a threat to either adjacent groundwater or soils. (5) WRI developed an Environmental Field Simulator (EFS) method for assessing the impact of flowable fill materials on adjacent soils and found that the zone of impact is less than a couple of inches, thereby posing no threat to adjacent soils. (6) Field-scale demonstrations of the MDU flowable fill were constructed and were successful for structural, as well as excavatable applications. Monitoring has demonstrated the geotechnical performance, environmental performance, and compatibility with common embed materials with the MDU flowable fill products. Technical and economic issues were identified that may hinder the commercial acceptance of MDU flowable fill materials, including: (1) the ability to produce a consistent product; (2) the ability to provide a product year round (cold weather retards strength development); and (3) the ability to evaluate and produce commercial quantities of MDU flowable fill using inexpensive materials.« less

Morphology and diversity of the forcipules in Strigamia centipedes (Chilopoda, Geophilomorpha).

PubMed

Maruzzo, Diego; Bonato, Lucio

2014-01-01

The morphology of the venomous limbs (forcipules) of 13 species of Strigamia and of six other geophilomorphs was studied with light microscopy, scanning electron microscopy, and, for a subsample, with confocal laser scanning microscopy. In all Strigamia species a well-distinct denticle is present invariantly on the inner side of the terminal article (tarsungulum), in sub-basal position, just proximal to a faint transverse sulcus and a cuticular introflexion that corresponds to the insertion point of a tendon. Strigamia species differ mainly in size and shape of the denticle and thickness of the distal part of the tarsungulum, suggesting some functional diversity in piercing and handling prey. Anatomical evidence supports the hypothesis that the tarsungulum corresponds to two ancestral articles and a denticle at the basis of the tarsungulum originated multiple times within geophilomorphs, however in different positions corresponding to either the ancestral sub-terminal article (in Strigamia, other Geophiloidea and some Schendylidae) or the ancestral terminal article (in the himantariid Thracophilus). Copyright © 2013 Elsevier Ltd. All rights reserved.

Mexiare gen. nov., a new Doryctinae genus (Hymenoptera: Braconidae) from Mexico with fused first and second metasomal tergites.

PubMed

Belokobylskij, Sergey A; Samaca-Sáenz, Ernesto; Zaldívar-Riverón, Alejandro

2015-01-27

A new braconid genus from the subfamily Doryctinae, Mexiare gen. nov. (type species M. toledoi sp. nov.) is described from the state of Morelos in Central Mexico. The described species of this genus is characterised by having immovably fused first and second metasomal tergites, a feature also present in species of two Oriental (Arhaconotus Belokobylskij and Mimipodoryctes Belokobylskij) and one Neotropical (Iare Barbalho et Penteado-Dias) genera. The new genus, however, can be distinguished from the Neotropical Iare by the presence of a semi-oval basal area on the second metasomal tergite, distinctly short submedial (subbasal) cell of hind wing, more than three hamuli, considerably short second radiomedial (submarginal) cell, narrow radial (marginal) cell of fore wing and mostly smooth mesoscutum. A phylogenetic analysis among doryctine genera based on two gene markers (28S and COI) placed Mexiare gen. nov. within a previously recovered major South American clade, though its relationships with other taxa remain unclear. 

Diabetic peripheral neuropathy assessment through texture based analysis of corneal nerve images

NASA Astrophysics Data System (ADS)

Silva, Susana F.; Gouveia, Sofia; Gomes, Leonor; Negrão, Luís; João Quadrado, Maria; Domingues, José Paulo; Morgado, António Miguel

2015-05-01

Diabetic peripheral neuropathy (DPN) is one common complication of diabetes. Early diagnosis of DPN often fails due to the non-availability of a simple, reliable, non-invasive method. Several published studies show that corneal confocal microscopy (CCM) can identify small nerve fibre damage and quantify the severity of DPN, using nerve morphometric parameters. Here, we used image texture features, extracted from corneal sub-basal nerve plexus images, obtained in vivo by CCM, to identify DPN patients, using classification techniques. A SVM classifier using image texture features was used to identify (DPN vs. No DPN) DPN patients. The accuracies were 80.6%, when excluding diabetic patients without neuropathy, and 73.5%, when including diabetic patients without diabetic neuropathy jointly with healthy controls. The results suggest that texture analysis might be used as a complementing technique for DPN diagnosis, without requiring nerve segmentation in CCM images. The results also suggest that this technique has enough sensitivity to detect early disorders in the corneal nerves of diabetic patients.

Degeneration and Regeneration of Subbasal Corneal Nerves after Infectious Keratitis: A Longitudinal In Vivo Confocal Microscopy Study.

PubMed

Müller, Rodrigo T; Abedi, Farshad; Cruzat, Andrea; Witkin, Deborah; Baniasadi, Neda; Cavalcanti, Bernardo M; Jamali, Arsia; Chodosh, James; Dana, Reza; Pavan-Langston, Deborah; Hamrah, Pedram

2015-11-01

To investigate the longitudinal alterations of subbasal corneal nerves in patients with infectious keratitis (IK) during the acute phase, cessation of treatment, and the recovery phase by in vivo confocal microscopy (IVCM). Prospective, longitudinal, case-control, single-center study. Fifty-six eyes of 56 patients with the diagnosis of bacterial (n=28), fungal (n=15), or Acanthamoeba (n=13) keratitis were included in the study. Thirty eyes of 30 normal volunteers constituted the control group. Corneal sensation and serial IVCM of the central cornea were performed prospectively using the Heidelberg Retina Tomograph 3/Rostock Cornea Module (Heidelberg Engineering, Heidelberg, Germany). The IVCM images were assessed at 3 time points: at the acute phase (first visit to the cornea service), at cessation of antimicrobial treatment, and up to 6 months after the resolution of infection. Total nerve number and length, main nerve trunks, branching, and corneal sensation were assessed during the follow-up period. Corneal nerves were reduced significantly during the acute phase in eyes with IK compared with controls across all subgroups, with total nerve length of 5.47±0.69 mm/mm2 versus 20.59±1.06 mm/mm2 (P<0.0001). At the cessation of treatment, corneal nerves in patients with IK had regenerated, including total nerve length (8.49±0.94 mm/mm2; P=0.02) and nerve branch length (4.80±0.37 mm/mm2; P=0.005). During the recovery phase, after resolution of infection, corneal nerves regenerated further, including total nerve length (12.13±1.97 mm/mm2; P=0.005), main nerve trunk length (5.80±1.00 mm/mm2; P=0.01), and nerve branch length (6.33±0.76 mm/mm2; P=0.003) as compared with the acute phase, but were still significantly lower when compared with controls (P<0.05 for all parameters). Corneal degeneration and regeneration correlated with corneal sensation (r=0.47; P=0.0009). Patients with IK who sustain profound loss of corneal nerves during the acute phase of infection demonstrate increased corneal nerve density during the first 6 months after the resolution of infection. However, despite significant nerve regeneration, corneal nerve density does not recover fully and remains low compared to controls. By providing an objective methodology to monitor corneal re-innervation, IVCM adds potentially important findings that may have implications for clinical management and surgical planning. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

The synergy of permeable pavements and geothermal heat pumps for stormwater treatment and reuse.

PubMed

Tota-Maharaj, K; Scholz, M; Ahmed, T; French, C; Pagaling, E

2010-12-14

The use of permeable pavement systems with integrated geothermal heat pumps for the treatment and recycling of urban runoff is novel and timely. This study assesses the efficiency of the combined technology for controlled indoor and uncontrolled outdoor experimental rigs. Water quality parameters such as biochemical oxygen demand, nutrients, total viable heterotrophic bacteria and total coliforms were tested before and after treatment in both rigs. The water borne bacterial community genomic deoxyribonucleic acid (DNA) was analyzed by polymerase chain reaction (PCR) amplification followed by denaturing gradient gel electrophoresis (DGGE) and was further confirmed by DNA sequencing techniques. Despite the relatively high temperatures in the indirectly heated sub-base of the pavement, potentially pathogenic organisms such as Salmonella spp., Escherichia coli, faecal Streptococci and Legionella were not detected. Moreover, mean removal rates of 99% for biochemical oxygen demand, 97% for ammonia-nitrogen and 95% for orthophosphate-phosphates were recorded. This research also supports decision-makers in assessing public health risks based on qualitative molecular microbiological data associated with the recycling of treated urban runoff.

Histologic Findings of Severe/Therapy-Resistant Asthma From Video-assisted Thoracoscopic Surgery Biopsies.

PubMed

Trejo Bittar, Humberto E; Doberer, Daniel; Mehrad, Mitra; Strollo, Diane C; Leader, Joseph K; Wenzel, Sally; Yousem, Samuel A

2017-02-01

The histologic changes occurring in severe/therapy-resistant asthma (SA) as defined by the European Respiratory Society/American Thoracic Society guidelines, particularly at the level of the distal airways are unknown. This study describes the clinical, radiologic, and histologic characteristics of 29 SA patients who underwent video-assisted thoracoscopic surgery lung biopsy. Pathologic observations were correlated with clinical features, especially the presence of autoimmune disease (AID) (15/29, 51.7%). Ten biopsies (10/29, 34.5%) showed only small airway manifestations of asthma, whereas in 19 (65.5%) asthmatic granulomatosis, manifested by asthmatic bronchiolitis supplemented by an alveolar septal mononuclear infiltrates with non-necrotizing granulomas, was present. SA patients without asthmatic granulomatosis showed more striking small airway injury, subbasement membrane thickening, and neutrophilic infiltrates. Cases with concurrent AID had a tendency to more parenchymal eosinophilic inflammation, more bronchiolocentric granulomas, and a suggestion of increased responsivity to nonsteroidal immunosuppressive therapy. Histologic examination of video-assisted thoracoscopic surgery lung biopsies in SA demonstrates diverse pathologies including cases associated with granulomatous inflammation in addition to eosinophilic infiltrates. This spectrum of histologies may link to a high incidence of AID.

Effect of Autologous Serum Eye Drops in Patients with Sjögren Syndrome-related Dry Eye: Clinical and In Vivo Confocal Microscopy Evaluation of the Ocular Surface.

PubMed

Semeraro, Francesco; Forbice, Eliana; Nascimbeni, Giuseppe; Taglietti, Marco; Romano, Vito; Guerra, Germano; Costagliola, Ciro

To evaluate in vivo changes after therapy using autologous serum (AS) eye drops in Sjögren's syndrome (SS)-related dry eyes by confocal microscopy. In this study, 24 patients with SS-related dry eyes [12 in AS eye drop therapy and 12 in artificial tear (AT) therapy] and 24 healthy volunteers were recruited. Ocular Surface Disease Index (OSDI), central corneal thickness, tear film, break-up time, corneal and conjunctival staining, Schirmer's test and corneal confocal microscopy were investigated. Tear production, tear stability, corneal staining, inflammation, and central corneal thickness, Langherans cells, activated keratocytes, intermediate epithelial cell density, nerve tortuosity, number of sub-basal nerve branches, and number of bead-like formations differed between patients and controls (p<0.0001). The AT and AS groups differed in the OSDI, number of branches, and number of beadings (p<0.0001). AS eye drops improve symptoms and confocal microscopy findings in SS-related dry eyes. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

In vivo laser confocal microscopic analysis of murine cornea and lens microstructures.

PubMed

Yuasa, Masashi; Kobayashi, Akira; Yokogawa, Hideaki; Sugiyama, Kazuhisa

2008-01-01

The purpose of the current study is to investigate in vivo microstructures of anterior segments of normal murine eyes by new-generation in vivo laser confocal microscopy. Twenty-six corneas and lenses from 13 mice were analyzed by in vivo laser confocal microscopy. Murine corneal superficial cells formed a polygonal cell pattern, with a mean cell density of 577 +/- 115 cells/mm2 (mean +/- standard deviation). Corneal basal epithelial cells had dark cytoplasm and were closely organized (9,312 +/- 1,777 cells/mm2). Sub-basal nerve fiber bundles were arranged in a whorl pattern, with both clockwise and counter-clockwise patterns. In the stroma, keratocytes were observed as numerous reflective stellate structures. The endothelial cells were organized in a honeycomb pattern (2,463 +/- 292 cells/mm2). Deeper inside the eye, murine lens epithelial cells were organized in a regular pattern (4,168 +/- 636 cells/mm2) and numerous lens fibers were observed. In vivo laser confocal microscopy can provide high-resolution images of all corneal layers and lens structures of mice without sacrificing animals or tissue preparation.

Recycling of waste spent catalyst in road construction and masonry blocks.

PubMed

Taha, Ramzi; Al-Kamyani, Zahran; Al-Jabri, Khalifa; Baawain, Mahad; Al-Shamsi, Khalid

2012-08-30

Waste spent catalyst is generated in Oman as a result of the cracking process of petroleum oil in the Mina Al-Fahl and Sohar Refineries. The disposal of spent catalyst is of a major concern to oil refineries. Stabilized spent catalyst was evaluated for use in road construction as a whole replacement for crushed aggregates in the sub-base and base layers and as a partial replacement for Portland cement in masonry blocks manufacturing. Stabilization is necessary as the waste spent catalyst exists in a powder form and binders are needed to attain the necessary strength required to qualify its use in road construction. Raw spent catalyst was also blended with other virgin aggregates, as a sand or filler replacement, for use in road construction. Compaction, unconfined compressive strength and leaching tests were performed on the stabilized mixtures. For its use in masonry construction, blocks were tested for unconfined compressive strength at various curing periods. Results indicate that the spent catalyst has a promising potential for use in road construction and masonry blocks without causing any negative environmental impacts. Copyright © 2012 Elsevier B.V. All rights reserved.

The corneal nerve density in the sub-basal plexus decreases with increasing myopia: a pilot study.

PubMed

Harrison, Wendy W; Putnam, Nicole M; Shukis, Christine; Nguyen, Evelyn; Reinard, Kristen; Hundelt, Elizabeth; Vardanyan, Galina; Gabai, Celine; Yevseyenkov, Vladimir

2017-07-01

Myopia can cause many changes in the health of the eye. As it becomes more prevalent worldwide, more patients seek correction in the form of glasses, contact lenses and refractive surgery. In this study we explore the impact that high myopia has on central corneal nerve density by comparing sub basal nerve plexus density measured by confocal microscopy in a variety of refractive errors. Seventy healthy adult subjects between the ages of 21-50 years participated in this study. The study took place in two phases with no overlapping subjects (n = 30 phase 1 and n = 40 phase 2). In both phases an autorefraction, keratometry reading, corneal thickness measure and confocal corneal scan of the sub basal nerve plexus were performed for both eyes. There were 11 hyperopes (+0.50 to +3.50DS), six emmetropes (-0.25 to +0.50DS), 30 low myopes (-5.50 to -0.50DS), and 23 high myopes (-5.50DS and above). In the second phase of the study additional tests were performed including an axial length, additional corneal scans, and a questionnaire that asked about age of first refractive correction and contact lens wear. Corneal nerves were imaged over the central cornea with a Nidek CS4 confocal microscope (460 × 345 μm field). Nerves were evaluated using the NeuronJ program for density calculation. One eye was selected for inclusion based on image quality and higher refractive error (more myopic or hyperopic). As myopia increased, nerve density decreased (t 1  = 3.86, p < 0.001). We also note a decrease in data scatter above -7 D. The relationship between axial length values and nerve density was also significant and the slope was not as robust as refractive error (t 1  = 2.4, p < 0.04). As expected there was a significant difference between the four groups in axial length (F 3  = 19.9, p < 0.001) and age of first refractive correction of the myopic groups (14.9 vs 11.5 years; t 46  = 2.99 p < 0.01). There was no difference in keratometry readings or corneal thickness between the groups (F 3  = 0.6, p = 0.66 and F 3  = 1.2, p = 0.33 respectively). Corneal nerve density in the sub-basal plexus decreased with increasing myopia. This could have implications for corneal surgery and contact lens wear in this patient population. © 2017 The Authors Ophthalmic & Physiological Optics © 2017 The College of Optometrists.

Resilient modulus of freeze-thaw affected granular soils for pavement design and evaluation. Part 4: Field validation tests at Albany County Airport

NASA Astrophysics Data System (ADS)

Johnson, T. C.; Crowe, A.; Erickson, M.; Cole, D. M.

1986-10-01

Stress-deformation data for unbound base, subbase, and silty sand subgrade soils in two airfield pavements were obtained from in situ tests and laboratory tests. Surface deflections were measured in the in situ tests, with a falling-weight deflectometer, when the soils were frozen, thawed, and at various stages of recovery from thaw weakening. The measured deflections were used to judge the validity of procedures developed for laboratory triaxial tests to determine nonlinear resilient moduli of specimens in the frozen, thawed and recovering states. The validity of the nonlinear resilient moduli, expressed as functions of externally applied stress and moisture tension, was confirmed by using the expressions to calculate surface deflections that were found to compare well with deflections measured in the in situ tests. The tests on specimens at various stages of recovery are especially significant because they show a strong dependence of the resilient modulus on moisture tension, leading to the conclusion that predictions or in situ measurements of moisture tension can be used to evaluate expected seasonal variation in the resilient modulus of granular soils.

Chronic migraine is associated with reduced corneal nerve fiber density and symptoms of dry eye.

PubMed

Kinard, Krista I; Smith, A Gordon; Singleton, J Robinson; Lessard, Margaret K; Katz, Bradley J; Warner, Judith E A; Crum, Alison V; Mifflin, Mark D; Brennan, Kevin C; Digre, Kathleen B

2015-04-01

We used in vivo corneal confocal microscopy to investigate structural differences in the sub-basal corneal nerve plexus in chronic migraine patients and a normal population. We used a validated questionnaire and tests of lacrimal function to determine the prevalence of dry eye in the same group of chronic migraine patients. Activation of the trigeminal system is involved in migraine. Corneal nociceptive sensation is mediated by trigeminal axons that synapse in the gasserian ganglion and the brainstem, and serve nociceptive, protective, and trophic functions. Noninvasive imaging of the corneal sub-basal nerve plexus is possible with in vivo corneal confocal microscopy. For this case-control study, we recruited chronic migraine patients and compared them with a sex- and age-similar group of control subjects. Patients with peripheral neuropathy, a disease known to be associated with a peripheral neuropathy, or prior corneal or intraocular surgery were excluded. Participants underwent in vivo corneal confocal microscopy using a Heidelberg Retinal Tomography III confocal microscope with a Rostock Cornea Module. Nerve fiber length, nerve branch density, nerve fiber density, and tortuosity coefficient were measured using established methodologies. Migraine participants underwent testing of basal tear production with proparacaine, corneal sensitivity assessment with a cotton-tip applicator, measurement of tear break-up time, and completion of a validated dry eye questionnaire. A total of 19 chronic migraine patients and 30 control participants completed the study. There were no significant differences in age or sex. Nerve fiber density was significantly lower in migraine patients compared with controls (48.4 ± 23.5 vs. 71.0 ± 15.0 fibers/mm2 , P < .001). Nerve fiber length was decreased in the chronic migraine group compared with the control group, but this difference was not statistically significant (21.5 ± 11.8 vs. 26.8 ± 5.9 mm/mm2, P < .084). Nerve branch density was similar in the two groups (114.0 ± 92.4 vs. 118.1 ± 55.9 branches/mm2 , P < .864). Tortuosity coefficient and log tortuosity coefficient also were similar in the chronic migraine and control groups. All migraine subjects had symptoms consistent with a diagnosis of dry eye syndrome. We found that in the sample used in this study, the presence of structural changes in nociceptive corneal axons lends further support to the hypothesis that the trigeminal system plays a critical role in the pathogenesis of migraine. In vivo corneal confocal microscopy holds promise as a biomarker for future migraine research as well as for studies examining alterations of corneal innervation. Dry eye symptoms appear to be extremely prevalent in this population. The interrelationships between migraine, corneal nerve architecture, and dry eye will be the subject of future investigations. © 2015 American Headache Society.

Life cycle assessment of disposal of residues from municipal solid waste incineration: recycling of bottom ash in road construction or landfilling in Denmark evaluated in the ROAD-RES model.

PubMed

Birgisdóttir, H; Bhander, G; Hauschild, M Z; Christensen, T H

2007-01-01

Two disposal methods for MSWI bottom ash were assessed in a new life cycle assessment (LCA) model for road construction and disposal of residues. The two scenarios evaluated in the model were: (i) landfilling of bottom ash in a coastal landfill in Denmark and (ii) recycling of bottom ash as subbase layer in an asphalted secondary road. The LCA included resource and energy consumption, and emissions associated with upgrading of bottom ash, transport, landfilling processes, incorporation of bottom ash in road, substitution of natural gravel as road construction material and leaching of heavy metals and salts from bottom ash in road as well as in landfill. Environmental impacts associated with emissions to air, fresh surface water, marine surface water, groundwater and soil were aggregated into 12 environmental impact categories: Global Warming, Photochemical Ozone Formation, Nutrient Enrichment, Acidification, Stratospheric Ozone Depletion, Human Toxicity via air/water/soil, Ecotoxicity in water/soil, and a new impact category, Stored Ecotoxicity to water/soil that accounts for the presence of heavy metals and very persistent organic compounds that in the long-term might leach. Leaching of heavy metals and salts from bottom ash was estimated from a series of laboratory leaching tests. For both scenarios, Ecotoxicity(water) was, when evaluated for the first 100 yr, the most important among the twelve impact categories involved in the assessment. Human Toxicity(soil) was also important, especially for the Road scenario. When the long-term leaching of heavy metals from bottom ash was evaluated, based on the total content of heavy metals in bottom ash, all impact categories became negligible compared to the potential Stored Ecotoxicity, which was two orders of magnitudes greater than Ecotoxicity(water). Copper was the constituent that gave the strongest contributions to the ecotoxicities. The most important resources consumed were clay as liner in landfill and the groundwater resource which was potentially spoiled due to leaching of salts from bottom ash in road. The difference in environmental impacts between landfilling and utilization of bottom ash in road was marginal when these alternatives were assessed in a life cycle perspective.

Translational Immunoimaging and Neuroimaging Demonstrate Corneal Neuroimmune Crosstalk.

PubMed

Hamrah, Pedram; Seyed-Razavi, Yashar; Yamaguchi, Takefumi

2016-11-01

Corneal immunoimaging and neuroimaging approaches facilitate in vivo analyses of the cornea, including high-resolution imaging of corneal immune cells and nerves. This approach facilitates the analyses of underlying immune and nerve alterations not detected by clinical slit-lamp examination alone. In this review, we describe recent work performed in our translational ocular immunology center with a focus on "bench-to-bedside" and "bedside-to-bench" research. The ability to visualize dendritiform immune cells (DCs) in patients with laser in vivo confocal microscopy (IVCM), recently discovered in the central murine cornea, has allowed us to demonstrate their utility as a potential surrogate biomarker for inflammatory ocular surface diseases. This biomarker for inflammation allows the measurement of therapeutic efficacy of anti-inflammatory drugs and its utility as an endpoint in clinical trials with high interobserver agreement. IVCM image analyses from our studies has demonstrated a significant increase in DC density and size in ocular disease, a positive correlation between DC density and clinical signs and symptoms of disease and pro-inflammatory tear cytokines, and a strong negative correlation between DC density and subbasal nerve density. In conjunction with preclinical research investigating the inflammatory state in a partial or fully denervated cornea, our results indicated that corneal nerves are directly involved in the regulation of homeostasis and immune privilege in the cornea.

In Vivo Confocal Microscopy of Corneal Nerves in Health and Disease

PubMed Central

Cruzat, Andrea; Qazi, Yureeda; Hamrah, Pedram

2016-01-01

In vivo confocal microscopy (IVCM) is becoming an indispensable tool for studying corneal physiology and disease. Enabling the dissection of corneal architecture at a cellular level, this technique offers fast and noninvasive in vivo imaging of the cornea with images comparable to that of ex vivo histochemical techniques. Corneal nerves bear substantial relevance to clinicians and scientists alike, given their pivotal roles in regulation of corneal sensation, maintenance of epithelial integrity, and proliferation and promotion of wound healing. Thus, IVCM offers a unique method to study corneal nerve alterations in a myriad of conditions, such as ocular and systemic diseases and following corneal surgery, without altering the tissue microenvironment. Of particular interest has been the correlation of corneal subbasal nerves to their function, which has been studied in normal eyes, contact lens wearers, and patients with keratoconus, infectious keratitis, corneal dystrophies, and neurotrophic keratopathy. Longitudinal studies have applied IVCM to investigate the effects of corneal surgery on nerves, demonstrating their regenerative capacity. IVCM is increasingly important in the diagnosis and management of systemic conditions such as peripheral diabetic neuropathy and, more recently, in ocular diseases. In this review, we outline the principles and applications of IVCM in the study of corneal nerves in various ocular and systemic diseases. PMID:27771327

[Corneal subbasal nerve density changes after laser in situ keratomileusis with mechanical microkeratome and femtosecond laser].

PubMed

Hu, Liang; Xie, Wenjia; Tang, Lei; Chen, Jia; Zhang, Dong; Yu, Peng; Qu, Jia

2015-01-01

To compare the corneal subbasal nerve density (SND) changes after laser in situ keratomileusis (LASIK) with a microkeratome and a femtosecond laser. Prospective clinical study. Sixty eyes of thirty myopes were included. Fifteen patients (30 eyes) underwent LASIK with the Moria II microkeratome, and the other 15 patients (30 eyes) with the 60 k Hz IntraLase femtosecond laser. Central, temporal and nasal corneal SNDs were measured by confocal microscopy and compared before surgery, 1 month, and 3 months after surgery. Analysis of variance and t test were used for comparing the differences between different time points and two groups. Preoperatively and 1 month, 3 months postoperatively, the SNDs were (16 728.30 ± 4 300.30), (1 875.42 ± 300.50) and (1 701.55 ± 194.11) µm/mm(2) in the central cornea, (11 379.70 ± 1 833.92), (1 341.20 ± 288.68) and (1 860.87 ± 147.60) µm/mm(2) in the temporal cornea, and (8 506.79 ± 662.83), (7 428.96 ± 712.99) and (8 044.32 ± 1 077.54) µm/mm(2) in the nasal cornea, respectively, in the microkeratome group, and (16 351.59 ± 3 503.88), (1 859.38 ± 452.93) and (2 043.67 ± 377.76) in the central cornea, (12 328.22 ± 2 007.43), (1 483.85 ± 371.28) and (2 126.31 ± 279.87) µm/mm(2) in the temporal cornea, and (8 347.91 ± 789.44), (1 475.53 ± 293.98) and (2 022.10 ± 282.89) µm/mm(2) in the nasal cornea, respectively, in the femtosecond laser group. The SNDs at three positions all decreased significantly at each time point postoperatively compared to the baseline values in both groups (1 and 3 months in the microkeratome group: central t = 18.981 and 18.912, temporal t = 30.121 and 27.921, and nasal t = 6.456 and 2.126; in the femtosecond laser group: central t = 22.667 and 22.379, temporal t = 29.000 and 28.376, and nasal t = 46.329 and 41.751; all P < 0.01, except 3 months at the nasal in the microkeratome group, P = 0.042). The nasal SND increased significantly from month 1 to month 3 (t = -3.921, P < 0.01) in the microkeratome group, and the temporal and nasal SNDs both increased significantly from month 1 to month 3 (t = -9.629 and -6.645, both P < 0.01) in the femtosecond group. There were no significant differences in the central SND between the two groups (F = 0.002, P = 0.96). Significant differences were found in the nasal SND between the groups at 1 month and 3 months (t = 42.281 and 29.608, both P < 0.01), and in the temporal SND at 3 months after surgery (t = -4.595, P < 0.01). Peripheral corneal nerve recovery occurred at 1 month after LASIK surgery. Patients with a femtosecond laser showed better corneal regeneration than those with a microkeratome.

Translational Immuno- and Neuro-imaging Demonstrate Corneal Neuro-immune Crosstalk

PubMed Central

Hamrah, Pedram; Seyed-Razavi, Yashar; Yamaguchi, Takefumi

2017-01-01

Corneal immuno- and neuro-imaging approaches facilitate in vivo analyses of the cornea, including high-resolution imaging of corneal immune cells and nerves. This approach facilitates the analyses of underlying immune and nerve alterations not detected by clinical slit-lamp examination alone. In this review, we describe recent work performed in our translational ocular immunology center with a focus on ‘bench-to-bedside’ and ‘bedside-to-bench’ research. The ability to visualize dendritiform immune cells (DCs) in patients with laser in vivo confocal microscopy (IVCM), recently discovered in the central murine cornea, has allowed us to demonstrated their utility as a potential surrogate biomarker for inflammatory ocular surface diseases. This biomarker for inflammation allows the measurement of therapeutic efficacy of anti-inflammatory drugs and its utility as an endpoint in clinical trials with high inter-observer agreement. IVCM image analyses from our studies demonstrated a significant increase in DC density and size in ocular disease, a positive correlation between DC density and clinical signs and symptoms of disease and pro-inflammatory tear cytokines, and a strong negative correlation between DC density and subbasal nerve density. In conjunction with pre-clinical research investigating the inflammatory state in a partial or fully denervated cornea, our results indicated that corneal nerves are directly involved in the regulation of homeostasis and immune privilege in the cornea. PMID:27631352

Corneal Structural Changes in Nonneoplastic and Neoplastic Monoclonal Gammopathies.

PubMed

Aragona, Pasquale; Allegra, Alessandro; Postorino, Elisa Imelde; Rania, Laura; Innao, Vanessa; Wylegala, Edward; Nowinska, Anna; Ieni, Antonio; Pisani, Antonina; Musolino, Caterina; Puzzolo, Domenico; Micali, Antonio

2016-05-01

To investigate corneal confocal microscopic changes in nonneoplastic and neoplastic monoclonal gammopathies. Three groups of subjects were considered: group 1, twenty normal subjects; group 2, fifteen patients with monoclonal gammopathy of undetermined significance (MGUS); group 3, eight patients with smoldering multiple myeloma and eight patients with untreated multiple myeloma. After hematologic diagnosis, patients underwent ophthalmologic exam and in vivo confocal microscopic study. The statistical analysis was performed using ANOVA and Student-Newman-Keuls tests and receiver operating characteristic (ROC) curve analysis. Epithelial cells of gammopathic patients showed significantly higher reflectivity than controls, demonstrated by optical density (P < 0.001). Subbasal nerve density, branching, and beading were significantly altered in gammopathic patients (P = 0.01, P = 0.02, P = 0.02, respectively). The number of keratocytes was significantly reduced in neoplastic patients (P < 0.001 versus both normal and MGUS) in the anterior, medium, and posterior stroma. The ROC curve analysis showed good sensitivity and specificity for this parameter. Group 2 and 3 keratocytes showed higher nuclear and cytoplasmatic reflectivity in the medium and posterior stroma. Endothelial cells were not affected. Patients with neoplastic gammopathies showed peculiar alterations of the keratocyte number, which appeared significantly reduced. A follow-up with corneal confocal microscopy of patients with MGUS is suggested as a useful tool to identify peripheral tissue alterations linked to possible neoplastic disease development.

Effects of Interlocking and Supporting Conditions on Concrete Block Pavements

NASA Astrophysics Data System (ADS)

Mahapatra, Geetimukta; Kalita, Kuldeep

2018-02-01

Concrete Block Paving (CBP) is widely used as wearing course in flexible pavements, preferably under light and medium vehicular loadings. Construction of CBP at site is quick and easy in quality control. Usually, flexible pavement design philosophy is followed in CBP construction, though it is structurally different in terms of small block elements with high strength concrete and their interlocking aspects, frequent joints and discontinuity, restrained edge etc. Analytical solution for such group action of concrete blocks under loading in a three dimensional multilayer structure is complex and thus, the need of conducting experimental studies is necessitated for extensive understanding of the load—deformation characteristics and behavior of concrete blocks in pavement. The present paper focuses on the experimental studies for load transfer characteristics of CBP under different interlocking and supporting conditions. It is observed that both interlocking and supporting conditions affect significantly on the load transfer behavior in CBP structures. Coro-lock block exhibits better performance in terms of load carrying capacity and distortion behavior under static loads. Plate load tests are performed over subgrade, granular sub-base (GSB), CBP with and without GSB using different block shapes. For an example case, the comparison of CBP with conventional flexible pavement section is also presented and it is found that CBP provides considerable benefit in terms of construction cost of the road structure.

Improvement in engineering properties of soft-soil using cement and lime additives: A case study of southern Vietnam

NASA Astrophysics Data System (ADS)

To-Anh Phan, Vu; Ngoc-Anh Pham, Kha

2018-04-01

This paper presents the experimental results of using two additives to improve natural soft soil properties in southern Vietnam (i.g., cement and cement-lime mixture). The specimens were prepared by compacting method. Firstly, the natural soil was mixed with cement or cement-lime to determine the optimum water contents of various additive contents. Then, optimum water content was used to produce samples to test some engineering properties such as unconfined compressive strength, splitting tensile strength, and Young’s modulus. The specimens were tested by various curing duration of 7, 14, and 28 days. Results indicated that using cement additive is suitable for improvement of soft soil in the local area and cement-soil stabilization can be replaced as the subbase layer of the flexible pavement according to current Vietnamese standard. In addition, a higher cement content has a greater compressive strength as well as tensile strength. Besides, the Young’ modulus has significantly increased with a long-term curing age and more cement content. No evidences of increasing in strength and modulus are found with the cement-lime-soil stabilization. Finally, the best-fit power function is established by the relationships between unconfined compressive strength and splitting tensile strength as well unconfined compressive strength and Young’s Modulus, with the coefficient of determination, R2>0.999.

In vivo imaging through the entire thickness of human cornea by full-field optical coherence tomography

NASA Astrophysics Data System (ADS)

Mazlin, Viacheslav; Xiao, Peng; Dalimier, Eugénie; Grieve, Kate; Irsch, Kristina; Sahel, José; Fink, Mathias; Boccara, Claude

2018-02-01

Despite obvious improvements in visualization of the in vivo cornea through the faster imaging speeds and higher axial resolutions, cellular imaging stays unresolvable task for OCT, as en face viewing with a high lateral resolution is required. The latter is possible with FFOCT, a method that relies on a camera, moderate numerical aperture (NA) objectives and an incoherent light source to provide en face images with a micrometer-level resolution. Recently, we for the first time demonstrated the ability of FFOCT to capture images from the in vivo human cornea1. In the current paper we present an extensive study of appearance of healthy in vivo human corneas under FFOCT examination. En face corneal images with a micrometer-level resolution were obtained from the three healthy subjects. For each subject it was possible to acquire images through the entire corneal depth and visualize the epithelium structures, Bowman's layer, sub-basal nerve plexus (SNP) fibers, anterior, middle and posterior stroma, endothelial cells with nuclei. Dimensions and densities of the structures visible with FFOCT, are in agreement with those seen by other cornea imaging methods. Cellular-level details in the images obtained together with the relatively large field-of-view (FOV) and contactless way of imaging make this device a promising candidate for becoming a new tool in ophthalmological diagnostics.

Corneal confocal microscopy following conventional, transepithelial, and accelerated corneal collagen cross-linking procedures for keratoconus.

PubMed

Touboul, David; Efron, Nathan; Smadja, David; Praud, Delphine; Malet, Florence; Colin, Joseph

2012-11-01

To compare early corneal healing following conventional, transepithelial, and accelerated corneal collagen cross-linking (CXL) protocols. Twenty-four patients with progressive keratoconus were divided into three groups to receive conventional, transepithelial, or accelerated CXL. In vivo corneal confocal microscopy was performed on each patient preoperatively and at 1, 3, and 6 months postoperatively. Closure of the epithelial wound was complete 3 days following conventional and accelerated CXL. The subbasal nerve plexus was essentially obliterated immediately following conventional and accelerated CXL, and virtually no nerve fibers had regenerated by 6 months. The anterior stroma showed significant changes 1 month following conventional CXL; these changes were similar but more pronounced following accelerated CXL. Observed stromal changes included complete obliteration of keratocytes, increased tissue reflectivity, a honeycomb-like appearance, and circular lacunae. Some recovery of keratocyte density was noted after 6 months. These changes were less pronounced in the mid-stroma, and there were no apparent changes to the posterior stroma or endothelium. The cornea appeared to be unaltered following transepithelial CXL. In vivo corneal confocal microscopy analysis of the postoperative impact of CXL on the cornea revealed clear differences among conventional, accelerated, and transepithelial CXL protocols. Accelerated CXL had a greater impact than conventional CXL on the anterior cornea, whereas transepithelial CXL did not appear to alter corneal morphology. Copyright 2012, SLACK Incorporated.

Assessment of highway pavements using GPR

NASA Astrophysics Data System (ADS)

Plati, Christina; Loizos, Andreas

2015-04-01

Highway infrastructure is a prerequisite for a functioning economy and social life. Highways, often prone to congestion and disruption, are one of the aspects of a modern transport network that require maximum efficiency if an integrated transport network, and sustainable mobility, is to be achieved. Assessing the condition of highway structures, to plan subsequent maintenance, is essential to allow the long-term functioning of a road network. Optimizing the methods used for such assessment will lead to better information being obtained about the road and underlying ground conditions. The condition of highway structures will be affected by a number of factors, including the properties of the highway pavement, the supporting sub-base and the subgrade (natural ground), and the ability to obtain good information about the entire road structure, from pavement to subgrade, allows appropriate maintenance programs to be planned. The maintenance of highway pavements causes considerable cost and in many cases obstruction to traffic flow. In this situation, methods that provide information on the present condition of pavement structure non-destructively and economically are of great interest. It has been shown that Ground-Penetrating-Radar (GPR), which is a Non Destructive Technique (NDT), can deliver information that is useful for the planning of pavement maintenance activities. More specifically GPR is used by pavement engineers in order to determine physical properties and characteristics of the pavement structure, information that is valuable for the assessment of pavement condition. This work gives an overview on the practical application of GPR using examples from highway asphalt pavements monitoring. The presented individual applications of GPR pavement diagnostics concern structure homogeneity, thickness of pavement layers, dielectric properties of asphalt materials etc. It is worthwhile mentioning that a number of applications are standard procedures, either separately or in combination with other NDT methods, but even for them there is still a room for improvement and there is still need to set stricter regulations Comparisons between radar results and ground truth data produce evidence in support of the statement that the accuracy and reliability of radar results is sufficient for facing many issues related to the evaluation of asphalt pavements. Thus, benefits and limits of this method are shown and recommendations for GPR inspections are presented. Acknowledgments: This work benefited from networking activities carried out within the EU funded COST Action TU1208 "Civil Engineering Applications of Ground Penetrating Radar."

USE AND KNOWLEDGE ON THE INFORMATION TECHNOLOGIES IN MEDICAL EDUCATION -BOSNIAN AND HERZEGOVINIAN EXPERIENCE

PubMed Central

Masic, Izet; Begic, Edin; Begic, Nedim

2016-01-01

Introduction: Information technologies (IT) are becoming a tool without which further education of both medical students and doctors would not be possible. Aim: The aim of this paper was to analyze the use of IT in the prism of two systems, the old system and the Bologna system. Material and methods: Answers from questionnaires from total of 459 students (2012/13–2015/16 generation) were analyzed. Results: The presence of large number of female students, in both systems is significant (p <0.05). About 92% of students of the old system and 98% of students of the Bologna system use computer in everyday work (only 36% of old system and 47% of the Bologna system are using “faculties” computers). The computer is used for entertainment, education, information (via Internet) and for communication (e-mail, chat, social networks) (68.5% of the old system and 84% of students of the Bologna system have chosen all 4 offered answers). MS Word and MS Power Point are significantly more used compared to the use of MS Excel in both systems (p <0.05). The knowledge necessary to use their computers student of both systems have acquired through individual work. Students feel that they need to improve knowledge of the treatment of sub-base (76% of students of the old system and 62% of students of the Bologna system). Having analyzed the generation of 2015/16, 84.5% of students of the Bologna system and 75% of students of the old system used smartphones or tablets. The purpose of using a smartphone is, in most cases for accessing the social networks. 77.4% of smartphone users of the Bologna system, or 73.3% of the users of the old system have installed an application from the medical field. We analyzed the opinions of the availability of online course content and the degree of computerization of the study process and the possibility of electronic access to the literature - the results are not at the appropriate level. Conclusion: Education in software solutions that are connected to databases processing, must be imperative in reform of the teaching process. IT can only improve the teaching process, the organization of the education system in most eminent universities is undeniably linked to information technologies. PMID:27147910

In vivo confocal microscopy of the cornea: New developments in image acquisition, reconstruction and analysis using the HRT-Rostock Corneal Module

PubMed Central

Petroll, W. Matthew; Robertson, Danielle M.

2015-01-01

The optical sectioning ability of confocal microscopy allows high magnification images to be obtained from different depths within a thick tissue specimen, and is thus ideally suited to the study of intact tissue in living subjects. In vivo confocal microscopy has been used in a variety of corneal research and clinical applications since its development over 25 years ago. In this article we review the latest developments in quantitative corneal imaging with the Heidelberg Retinal Tomograph with Rostock Corneal Module (HRT-RCM). We provide an overview of the unique strengths and weaknesses of the HRT-RCM. We discuss techniques for performing 3-D imaging with the HRT-RCM, including hardware and software modifications that allow full thickness confocal microscopy through focusing (CMTF) of the cornea, which can provide quantitative measurements of corneal sublayer thicknesses, stromal cell and extracellular matrix backscatter, and depth dependent changes in corneal keratocyte density. We also review current approaches for quantitative imaging of the subbasal nerve plexus, which require a combination of advanced image acquisition and analysis procedures, including wide field mapping and 3-D reconstruction of nerve structures. The development of new hardware, software, and acquisition techniques continues to expand the number of applications of the HRT-RCM for quantitative in vivo corneal imaging at the cellular level. Knowledge of these rapidly evolving strategies should benefit corneal clinicians and basic scientists alike. PMID:25998608

GPR measurements and estimation for road subgrade damage caused by neighboring train vibration load

NASA Astrophysics Data System (ADS)

Zhao, Yonghui; Lu, Gang; Ge, Shuangcheng

2015-04-01

Generally, road can be simplified as a three-layer structure, including subgrade, subbase and pavement. Subgrade is the native material underneath a constructed road. It is commonly compacted before the road construction, and sometimes stabilized by the addition of asphalt, lime or other modifiers. As the mainly supporting structure, subgrade damage would lead in pavement settlement, displacement and crack. Assessment and monitoring of the subgrade condition currently involves trial pitting and subgrade sampling. However there is a practical limit on spatial density at which trail pits and cores can be taken. Ground penetrating radar (GPR) has been widely used to characterize highway pavement profiling, concrete structure inspection and railroad track ballast estimation. GPR can improve the economics of road maintenance. Long-term train vibration load might seriously influence the stability of the subgrade of neighboring road. Pavement settlement and obvious cracks have been found at a municipal road cross-under a railway with culvert box method. GPR test was conducted to estimate the subgrade and soil within 2.0 m depth for the further road maintenance. Two survey lines were designed in each lane, and total 12 GPR sections have been implemented. Considering both the penetrating range and the resolution, a antenna with a 500 MHz central frequency was chosen for on-site GPR data collection. For data acquisition, we used the default operating environment and scanning parameters for the RAMAC system: 60kHz transmission rate, 50 ns time window, 1024 samples per scan and 0.1 m step-size. Continuous operation was used; the antenna was placed on the road surface and slowly moved along the road. The strong surrounding disturbance related to railroad and attachments, might decrease the reliability of interpretation results. Some routine process methods (including the background removing, filtering) have been applied to suppress the background noise. Additionally, attribute analysis is an important tool that focused on the multi-properties of the signal. Here, cross-correlation attribute analysis has been applied for GPR profile interpretation. It compares one trace with surrounding traces to determine degrees of similar, and improves the difference between the reflected wave from detection target and its surrounding mediums, which makes it easy to detect the anomaly that couldn't be found in original GPR time profile. It's possible to identify sections of subgrade in good or worse condition, which may require specific maintenance or trail pitting investigation.

In Vivo Confocal Microscopic Evaluation of Corneal Langerhans Cells in Dry Eye Patients§

PubMed Central

Machetta, Federica; Fea, Antonio M; Actis, Alessandro G; de Sanctis, Ugo; Dalmasso, Paola; Grignolo, Federico M

2014-01-01

Purpose. To assess inflammatory involvement of cornea in dry eye by means of confocal microscopy, evaluating the presence and distribution of Langherans cells (LCs). Methods: 98 eyes of 49 subjects were enrolled: 18 subjects affected by Sjögren Syndrome Dry Eye (SSDE), 17 with Non-Sjögren Syndrome Dry Eye (NSSDE), 14 healthy volunteeers. Dry eye symptoms, tear film, ocular surface damage and corneal confocal microscopy were analized. Results: A significant increase of LCs density was observed at sub-basal nerve plexus (SSDE = 79 cells/mm2 andNDE = 22 cells/mm2; p = 0,0031) and sub-epithelial nerve plexus (SSDE = 38 cells/mm2 and NDE = 3 cells/mm2; p = 0,0169) in central cornea of SSDE group. An increased number of LCs from the center to the periphery of the cornea was observed, significant only in healthy volunteers group. In dry eye patients there was an increase in LCs density in both peripheral and central cornea with a significant difference between NDE (14,66 cells/mm2) and SSDE (56,66 cells/mm2) only in central cornea (p = 0,0028). In SSDE group, mean density of LCs in central cornea results also superior to NSSDE group (29,33 cells/mm2). There was no correlation between LCs density and dry eye symptoms, tear film deficiency and ocular surface damage. Conclusion: This study demonstrates the activation of an inflammatory and immunological reaction in cornea of NSSDE and SSDE patients. Confocal microscopy can be an important diagnostic tool in evaluation and follow-up of dry eye disease. PMID:25317216

Clogging evaluation of porous asphalt concrete cores in conjunction with medical x-ray computed tomography

NASA Astrophysics Data System (ADS)

Su, Yu-Min; Hsu, Chen-Yu; Lin, Jyh-Dong

2014-03-01

This study was to assess the porosity of Porous Asphalt Concrete (PAC) in conjunction with a medical X-ray computed tomography (CT) facility. The PAC was designed as the surface course to achieve the target porosity 18%. There were graded aggregates, soils blended with 50% of coarse sand, and crushed gravel wrapped with geotextile compacted and served as the base, subbase, and infiltration layers underneath the PAC. The test site constructed in 2004 is located in Northern of Taiwan in which the daily traffic has been light and limited. The porosity of the test track was investigated. The permeability coefficient of PAC was found severely degraded from 2.2×10-1 to 1.2×10-3 -cm/sec, after nine-year service, while the permeability below the surface course remained intact. Several field PAC cores were drilled and brought to evaluate the distribution of air voids by a medical X-ray CT nondestructively. The helical mode was set to administrate the X-ray CT scan and two cross-sectional virtual slices were exported in seconds for analyzing air voids distribution. It shows that the clogging of voids occurred merely 20mm below the surface and the porosity can reduce as much about 3%. It was also found that the roller compaction can decrease the porosity by 4%. The permeability reduction in this test site can attribute to the voids of PAC that were compacted by roller during the construction and filled by the dusts on the surface during the service.

Hyperosmolar Tears Induce Functional and Structural Alterations of Corneal Nerves: Electrophysiological and Anatomical Evidence Toward Neurotoxicity

PubMed Central

Hirata, Harumitsu; Mizerska, Kamila; Marfurt, Carl F.; Rosenblatt, Mark I.

2015-01-01

Purpose In an effort to elucidate possible neural mechanisms underlying diminished tearing in dry eye disease, this study sought to determine if hyperosmolar tears, a ubiquitous sign of dry eye disease, produce functional changes in corneal nerve responses to drying of the cornea and if these changes correlate with alterations in corneal nerve morphology. Methods In vivo extracellular electrophysiological recordings were performed in rat trigeminal ganglion neurons that innervated the cornea before, and up to 3 hours after, the ocular application of continuous hyperosmolar tears or artificial tears. In corollary experiments, immunohistochemical staining was performed to compare corneal nerve morphology in control and in eyes treated with hyperosmolar solutions. Results Our previous studies identified a population of corneal afferents, dry-sensitive neurons that are strongly excited by corneal dessication (“dry response”), a response thought to trigger the lacrimation reflex. In the present study, we found that the dry responses of corneal dry-sensitive neurons were depressed or even completely abolished by hyperosmolar tears in a time- (30 minutes to 3 hours) and dose (450- to 1000-mOsm solutions)-dependent manner. Furthermore, eyes treated with hyperosmolar tears for 3 hours contained large numbers of morphologically abnormal (granular, fragmented, or prominently beaded) subbasal nerves that appeared to be undergoing degeneration. Conclusions These results demonstrate that tear hyperosmolarity, considered to be a “core” mechanism of dry eye disease, significantly decreases physiological sensitivity and morphologic integrity of the corneal nerves important in tear production. These alterations might contribute to the diminished tearing seen clinically in dry eye patients. PMID:26720465

Hyperosmolar Tears Induce Functional and Structural Alterations of Corneal Nerves: Electrophysiological and Anatomical Evidence Toward Neurotoxicity.

PubMed

Hirata, Harumitsu; Mizerska, Kamila; Marfurt, Carl F; Rosenblatt, Mark I

2015-12-01

In an effort to elucidate possible neural mechanisms underlying diminished tearing in dry eye disease, this study sought to determine if hyperosmolar tears, a ubiquitous sign of dry eye disease, produce functional changes in corneal nerve responses to drying of the cornea and if these changes correlate with alterations in corneal nerve morphology. In vivo extracellular electrophysiological recordings were performed in rat trigeminal ganglion neurons that innervated the cornea before, and up to 3 hours after, the ocular application of continuous hyperosmolar tears or artificial tears. In corollary experiments, immunohistochemical staining was performed to compare corneal nerve morphology in control and in eyes treated with hyperosmolar solutions. Our previous studies identified a population of corneal afferents, dry-sensitive neurons that are strongly excited by corneal dessication ("dry response"), a response thought to trigger the lacrimation reflex. In the present study, we found that the dry responses of corneal dry-sensitive neurons were depressed or even completely abolished by hyperosmolar tears in a time- (30 minutes to 3 hours) and dose (450- to 1000-mOsm solutions)-dependent manner. Furthermore, eyes treated with hyperosmolar tears for 3 hours contained large numbers of morphologically abnormal (granular, fragmented, or prominently beaded) subbasal nerves that appeared to be undergoing degeneration. These results demonstrate that tear hyperosmolarity, considered to be a "core" mechanism of dry eye disease, significantly decreases physiological sensitivity and morphologic integrity of the corneal nerves important in tear production. These alterations might contribute to the diminished tearing seen clinically in dry eye patients.

Early Corneal Cellular and Nerve Fiber Pathology in Young Patients With Type 1 Diabetes Mellitus Identified Using Corneal Confocal Microscopy.

PubMed

Szalai, Eszter; Deák, Eszter; Módis, László; Németh, Gábor; Berta, András; Nagy, Annamária; Felszeghy, Eniko; Káposzta, Rita; Malik, Rayaz A; Csutak, Adrienne

2016-03-01

The aim of this study was to quantify epithelial, stromal, and endothelial cell density, and subbasal nerve morphology in young patients with type 1 diabetes mellitus with and without diabetic retinopathy. A total of 28 young patients (mean age, 22.86 ± 9.05 years) with type 1 diabetes, with (n = 18) and without (n = 10) retinopathy, and 17 age-matched healthy control subjects (mean age, 26.53 ± 2.43 years) underwent corneal confocal microscopy (CCM). We found significantly lower epithelial (P < 0.0001) and endothelial (P = 0.001) cell densities and higher keratocyte cell density (P = 0.024) in patients with type 1 diabetes compared to controls. Significantly lower corneal nerve fiber density (P = 0.004), nerve branch density (P = 0.004), total nerve branch density (P = 0.04), and nerve fiber length (P = 0.001), and greater nerve fiber width (P = 0.04) were observed in patients with type 1 diabetes compared to control subjects. Significantly lower epithelial (P < 0.001) and endothelial (P = 0.02) cell densities, nerve branch density (P = 0.02), and nerve fiber length (P = 0.04), and significantly higher keratocyte cell density (P = 0.02) were found in patients with type 1 diabetes without retinopathy compared to control subjects. Corneal confocal microscopy identifies corneal cellular and small nerve fiber pathology in young patients with type 1 diabetes without retinopathy, which increases in severity in those with retinopathy. Corneal confocal microscopy appears to have considerable use as an imaging biomarker for early subclinical pathology in young patients with type 1 diabetes mellitus.

Kindia (Pavetteae, Rubiaceae), a new cliff-dwelling genus with chemically profiled colleter exudate from Mt Gangan, Republic of Guinea

PubMed Central

Cheek, Martin; Magassouba, Sékou; Howes, Melanie-Jayne R.; Doré, Tokpa; Doumbouya, Saïdou; Molmou, Denise; Grall, Aurélie; Couch, Charlotte

2018-01-01

A new genus Kindia (Pavetteae, Rubiaceae) is described with a single species, Kindia gangan, based on collections made in 2016 during botanical exploration of Mt Gangan, Kindia, Republic of Guinea in West Africa. The Mt Gangan area is known for its many endemic species including the only native non-neotropical Bromeliaceae Pitcairnia feliciana. Kindia is the fourth endemic vascular plant genus to be described from Guinea. Based on chloroplast sequence data, the genus is part of Clade II of tribe Pavetteae. In this clade, it is sister to Leptactina sensu lato (including Coleactina and Dictyandra). K. gangan is distinguished from Leptactina s.l. by the combination of the following characters: its epilithic habit; several-flowered axillary inflorescences; distinct calyx tube as long as the lobes; a infundibular-campanulate corolla tube with narrow proximal section widening abruptly to the broad distal section; presence of a dense hair band near base of the corolla tube; anthers and style deeply included, reaching about mid-height of the corolla tube; anthers lacking connective appendages and with sub-basal insertion; pollen type 1; pollen presenter (style head) winged and glabrous (smooth and usually hairy in Leptactina); orange colleters producing a vivid red exudate, which encircle the hypanthium, and occur inside the calyx and stipules. Kindia is a subshrub that appears restricted to bare, vertical rock faces of sandstone. Fruit dispersal and pollination by bats is postulated. Here, it is assessed as Endangered EN D1 using the 2012 IUCN standard. High resolution LC-MS/MS analysis revealed over 40 triterpenoid compounds in the colleter exudate, including those assigned to the cycloartane class. Triterpenoids are of interest for their diverse chemical structures, varied biological activities, and potential therapeutic value. PMID:29692954

Stormwater harvesting for irrigation purposes: an investigation of chemical quality of water recycled in pervious pavement system.

PubMed

Nnadi, Ernest O; Newman, Alan P; Coupe, Stephen J; Mbanaso, Fredrick U

2015-01-01

Most available water resources in the world are used for agricultural irrigation. Whilst this level of water use is expected to increase due to rising world population and land use, available water resources are expected to become limited due to climate change and uneven rainfall distribution. Recycled stormwater has the potential to be used as an alternative source of irrigation water and part of sustainable water management strategy. This paper reports on a study to investigate whether a sustainable urban drainage system (SUDS) technique, known as the pervious pavements system (PPS) has the capability to recycle water that meets irrigation water quality standard. Furthermore, the experiment provided information on the impact of hydrocarbon (which was applied to simulate oil dripping from parked vehicles onto PPS), leaching of nutrients from different layers of the PPS and effects of nutrients (applied to enhance bioremediation) on the stormwater recycling efficiency of the PPS. A weekly dose of 6.23 × 10(-3) L of lubricating oil and single dose of 17.06 g of polymer coated controlled-release fertilizer granules were applied to the series of 710 mm × 360 mm model pervious pavement structure except the controls. Rainfall intensity of 7.4 mm/h was applied to the test models at the rate of 3 events per week. Analysis of the recycled water showed that PPS has the capability to recycle stormwater to a quality that meets the chemical standards for use in agricultural irrigation irrespective of the type of sub-base used. There is a potential benefit of nutrient availability in recycled water for plants, but care should be taken not to dispose of this water in natural water courses as it might result in eutrophication problems. Copyright © 2014 Elsevier Ltd. All rights reserved.

Ca2+-Activated K+ Channel–3.1 Blocker TRAM-34 Attenuates Airway Remodeling and Eosinophilia in a Murine Asthma Model

PubMed Central

Girodet, Pierre-Olivier; Ozier, Annaig; Carvalho, Gabrielle; Ilina, Olga; Ousova, Olga; Gadeau, Alain-Pierre; Begueret, Hugues; Wulff, Heike; Marthan, Roger; Bradding, Peter

2013-01-01

Key features of asthma include bronchial hyperresponsiveness (BHR), eosinophilic airway inflammation, and bronchial remodeling, characterized by subepithelial collagen deposition, airway fibrosis, and increased bronchial smooth muscle (BSM) mass. The calcium-activated K+ channel KCa3.1 is expressed by many cells implicated in the pathogenesis of asthma, and is involved in both inflammatory and remodeling responses in a number of tissues. The specific KCa3.1 blocker 5-[(2-chlorophenyl)(diphenyl)methyl]-1H-pyrazole (TRAM-34) attenuates BSM cell proliferation, and both mast cell and fibrocyte recruitment in vitro. We aimed to examine the effects of KCa3.1 blockade on BSM remodeling, airway inflammation, and BHR in a murine model of chronic asthma. BALB/c mice were sensitized with intraperitoneal ovalbumin (OVA) on Days 0 and 14, and then challenged with intranasal OVA during Days 14–75. OVA-sensitized/challenged mice received TRAM-34 (120 mg/kg/day, subcutaneous) from Days −7 to 75 (combined treatment), Days −7 to 20 (preventive treatment), or Days 21 to 75 (curative treatment). Untreated mice received daily injections of vehicle (n = 8 per group). Bronchial remodeling was assessed by histological and immunohistochemical analyses. Inflammation was evaluated using bronchoalveolar lavage and flow cytometry. We also determined BHR in both conscious and anesthetized mice via plethysmography. We demonstrated that curative treatment with TRAM-34 abolishes BSM remodeling and subbasement collagen deposition, and attenuates airway eosinophilia. Although curative treatment alone did not significantly reduce BHR, the combined treatment attenuated nonspecific BHR to methacholine. This study indicates that KCa3.1 blockade could provide a new therapeutic strategy in asthma. PMID:23204391

Using corneal confocal microscopy to track changes in the corneal layers of dry eye patients after autologous serum treatment.

PubMed

Mahelkova, Gabriela; Jirsova, Katerina; Seidler Stangova, Petra; Palos, Michalis; Vesela, Viera; Fales, Ivan; Jiraskova, Nada; Dotrelova, Dagmar

2017-05-01

In vivo corneal confocal microscopy allows the examination of each layer of the cornea in detail and the identification of pathological changes at the cellular level. The purpose of this study was to identify the possible effects of a three-month treatment with autologous serum eye-drops in different corneal layers of patients with severe dry eye disease using corneal confocal microscopy. Twenty-six patients with dry eye disease were included in the study. Corneal fluorescein staining was performed. The corneas of the right eyes were examined using in vivo corneal confocal microscopy before and after a three-month treatment with autologous serum drops. The densities of superficial and basal epithelial cells, Langerhans cells, the keratocytes and activated keratocytes, the density of endothelial cells and the status of the sub-basal nerve plexus fibres were evaluated. A significant decrease in corneal fluorescein staining was found after the three-month autologous serum treatment (p = 0.0006). The basal epithelial cell density decreased significantly (p = 0.001), while the density of superficial epithelial cells did not change significantly (p = 0.473) nor did the number of Langerhans cells or activated keratocytes (p = 0.223; p = 0.307, respectively). There were no differences in the other corneal cell layers or in the status of the nerve fibres. The results demonstrate the ability of corneal confocal microscopy to evaluate an improvement in the basal epithelial cell layer of the cornea after autologous serum treatment in patients with dry eye disease. More studies with longer follow-up periods are needed to elucidate the suitability of corneal confocal microscopy to follow the effect of autologous serum treatment on nerve fibres or other corneal layers in dry eye disease patients. © 2016 Optometry Australia.

Effect of combination therapy consisting of enalapril, α-lipoic acid, and menhaden oil on diabetic neuropathy in a high fat/low dose streptozotocin treated rat.

PubMed

Davidson, Eric P; Holmes, Amey; Coppey, Lawrence J; Yorek, Mark A

2015-10-15

We have previously demonstrated that treating diabetic rats with enalapril, an angiotensin converting enzyme (ACE) inhibitor, α-lipoic acid, an antioxidant, or menhaden oil, a natural source of omega-3 fatty acids can partially improve diabetic peripheral neuropathy. In this study we sought to determine the efficacy of combining these three treatments on vascular and neural complications in a high fat fed low dose streptozotocin treated rat, a model of type 2 diabetes. Rats were fed a high fat diet for 8 weeks followed by a 30 mg/kg dose of streptozotocin. Eight weeks after the onset of hyperglycemia diabetic rats were treated with a combination of enalapril, α-lipoic acid and menhaden oil. Diabetic rats not receiving treatment were continued on the high fat diet. Glucose clearance was impaired in diabetic rats and significantly improved with treatment. Diabetes caused steatosis, elevated serum lipid levels, slowing of motor and sensory nerve conduction, thermal hypoalgesia, reduction in intraepidermal nerve fiber profiles, decrease in cornea sub-basal nerve fiber length and corneal sensitivity and impairment in vascular relaxation to acetylcholine and calcitonin gene-related peptide in epineurial arterioles of the sciatic nerve. Treating diabetic rats with the combination of enalapril, α-lipoic acid and menhaden oil reversed all these deficits to near control levels except for motor nerve conduction velocity which was also significantly improved compared to diabetic rats but remained significantly decreased compared to control rats. These studies suggest that a combination therapeutic approach may be most effective for treating vascular and neural complications of type 2 diabetes. Published by Elsevier B.V.

In Vivo Confocal Microscopy of the Ocular Surface: From Bench to Bedside

PubMed Central

Villani, Edoardo; Baudouin, Christophe; Efron, Nathan; Hamrah, Pedram; Kojima, Takashi; Patel, Sanjay V.; Pflugfelder, Stephen C.; Zhivov, Andrey; Dogru, Murat

2014-01-01

In vivo confocal microscopy (IVCM) is an emerging technology that provides minimally invasive, high resolution, steady-state assessment of the ocular surface at the cellular level. Several challenges still remain but, at present, IVCM may be considered a promising technique for clinical diagnosis and management. This mini-review summarizes some key findings in IVCM of the ocular surface, focusing on recent and promising attempts to move “from bench to bedside”. IVCM allows prompt diagnosis, disease course follow-up, and management of potentially blinding atypical forms of infectious processes, such as acanthamoeba and fungal keratitis. This technology has improved our knowledge of corneal alterations and some of the processes that affect the visual outcome after lamellar keratoplasty and excimer keratorefractive surgery. In dry eye disease, IVCM has provided new information on the whole-ocular surface morphofunctional unit. It has also improved understanding of pathophysiologic mechanisms and helped in the assessment of prognosis and treatment. IVCM is particularly useful in the study of corneal nerves, enabling description of the morphology, density, and disease- or surgically induced alterations of nerves, particularly the subbasal nerve plexus. In glaucoma, IVCM constitutes an important aid to evaluate filtering blebs, to better understand the conjunctival wound healing process, and to assess corneal changes induced by topical antiglaucoma medications and their preservatives. IVCM has significantly enhanced our understanding of the ocular response to contact lens wear. It has provided new perspectives at a cellular level on a wide range of contact lens complications, revealing findings that were not previously possible to image in the living human eye. The final section of this mini-review provides a focus on advances in confocal microscopy imaging. These include 2D wide-field mapping, 3D reconstruction of the cornea and automated image analysis. PMID:24215436

Ca(2+)-activated K(+) channel-3.1 blocker TRAM-34 attenuates airway remodeling and eosinophilia in a murine asthma model.

PubMed

Girodet, Pierre-Olivier; Ozier, Annaig; Carvalho, Gabrielle; Ilina, Olga; Ousova, Olga; Gadeau, Alain-Pierre; Begueret, Hugues; Wulff, Heike; Marthan, Roger; Bradding, Peter; Berger, Patrick

2013-02-01

Key features of asthma include bronchial hyperresponsiveness (BHR), eosinophilic airway inflammation, and bronchial remodeling, characterized by subepithelial collagen deposition, airway fibrosis, and increased bronchial smooth muscle (BSM) mass. The calcium-activated K(+) channel K(Ca)3.1 is expressed by many cells implicated in the pathogenesis of asthma, and is involved in both inflammatory and remodeling responses in a number of tissues. The specific K(Ca)3.1 blocker 5-[(2-chlorophenyl)(diphenyl)methyl]-1H-pyrazole (TRAM-34) attenuates BSM cell proliferation, and both mast cell and fibrocyte recruitment in vitro. We aimed to examine the effects of K(Ca)3.1 blockade on BSM remodeling, airway inflammation, and BHR in a murine model of chronic asthma. BALB/c mice were sensitized with intraperitoneal ovalbumin (OVA) on Days 0 and 14, and then challenged with intranasal OVA during Days 14-75. OVA-sensitized/challenged mice received TRAM-34 (120 mg/kg/day, subcutaneous) from Days -7 to 75 (combined treatment), Days -7 to 20 (preventive treatment), or Days 21 to 75 (curative treatment). Untreated mice received daily injections of vehicle (n = 8 per group). Bronchial remodeling was assessed by histological and immunohistochemical analyses. Inflammation was evaluated using bronchoalveolar lavage and flow cytometry. We also determined BHR in both conscious and anesthetized mice via plethysmography. We demonstrated that curative treatment with TRAM-34 abolishes BSM remodeling and subbasement collagen deposition, and attenuates airway eosinophilia. Although curative treatment alone did not significantly reduce BHR, the combined treatment attenuated nonspecific BHR to methacholine. This study indicates that K(Ca)3.1 blockade could provide a new therapeutic strategy in asthma.

In vivo confocal microscopic investigation of the cornea after autologous implantation of lenticules obtained through small incision lenticule extraction for treatment of hyperopia.

PubMed

Li, Meiyan; Li, Meng; Sun, Ling; Han, Tian; Ding, Lan; Xiang, Jun; Zhou, Xingtao

2018-01-01

To investigate re-innervation in the implanted lenticule, as well as changes to the cornea, after correcting hyperopia with an autologous implantation of a lenticule obtained through small incision lenticule extraction (SMILE). This study retrospectively analysed re-innervation in the implanted lenticule, as well as microscopic morphological changes in the corneal architecture of the recipient cornea in five patients (with myopia in one eye and hyperopia in the contralateral eye) who received SMILE in the myopic eye and femtosecond laser in situ keratomileusis (FS-LASIK) combined with lenticule implantation in the contralateral hyperopic eye. Re-innervation in the implanted lenticule, as well as microscopic morphological changes in corneal architecture, were evaluated by in vivo confocal microscopy. One patient was examined at postoperative week six, two were examined at postoperative month two, one was examined at postoperative month nine, and one was examined at postoperative month 12. Partial subbasal nerve fibre regeneration was detected in two patients (Case 4 who was examined at postoperative month nine and Case 5 who was examined at postoperative month 12). Regenerated and branched nerve fibres were detected in the implanted lenticule in Case 5 who was examined at postoperative month 12. Both the anterior and posterior interfaces showed an absence or decrease of keratocytes and the presence of small particles of various brightnesses. Keratocytes in the implanted lenticule presented abnormal morphology in size and shape after surgery in all treated eyes, but showed partial morphological recovery in two patients (Case 4 who was examined at postoperative month nine and Case 5 who was examined at postoperative month 12). These preliminary findings suggest that nerve fibres will regenerate into the implanted lenticule after autologous lenticule implantation. Keratocytes in lenticules demonstrated a gradual return to a normal morphology. © 2017 Optometry Australia.

Carl Jung's interpretation of Wolfgang Pauli's dreams: The Bailey Island, Maine, and New York City seminars of 1936 and 1937

NASA Astrophysics Data System (ADS)

Brown, Richard Paul

This dissertation reviewed the development of Jung's dream theory and addresses the question as to whether or not Jung was influenced by the dreams of the Nobel Prize winning physicist, Wolfgang Pauli. Jung provided an extensive analysis of Pauli's dreams, which are contained in the lightly edited, unpublished transcripts of lectures delivered in 1936 and 1937. An archival and hermeneutic analysis of the texts reveals a staged process of individuation that Jung related to in many ways because of the parallels to his own personal journey toward individuation. A chronological history of the development of Jung's dream theory is presented, followed by a picture of the relationship between Jung and Pauli. Thereafter, a detailed summary of the seminar transcripts, one given on Bailey Island, Maine, and the other in New York City the following year, is offered with hermeneutic commentary. An analysis of the seminars found that Pauli's dreams did, in part, support Jung's theory. Specifically, while Jung was unable to meet the scientific demands for clear empirical evidence of his dream theory, he did offer his professional and non-professional audiences with a slightly less rigorous example of his dream theory in action, demonstrating that the process shared similarities across peoples, time, and cultures. Additionally, in Pauli he found a superior mind that had gone through the process of individuation in accordance with his theory and his own experience. During the course of research, reference to a document was found in the correspondence in the Jungian Archives in Zurich. This document entitled, "FAREWELL SPEECH, Given by Dr. C. G. Jung on the Occasion of a Dinner Given in His Honor by the Analytical Psychology Club of New York City October 26, 1937" and other related documents were subsequently uncovered in the sub-basement of the Kristine Mann Library in New York City. A synopsis of the discovery and description of the papers contained in the file are discussed in the Conclusion.

Mono-static GPR without transmitting anything for pavement damage inspection: interferometry by auto-correlation applied to mobile phone signals

NASA Astrophysics Data System (ADS)

Feld, R.; Slob, E. C.; Thorbecke, J.

2015-12-01

Creating virtual sources at locations where physical receivers have measured a response is known as seismic interferometry. A much appreciated benefit of interferometry is its independence of the actual source locations. The use of ambient noise as actual source is therefore not uncommon in this field. Ambient noise can be commercial noise, like for example mobile phone signals. For GPR this can be useful in cases where it is not possible to place a source, for instance when it is prohibited by laws and regulations. A mono-static GPR antenna can measure ambient noise. Interferometry by auto-correlation (AC) places a virtual source on this antenna's position, without actually transmitting anything. This can be used for pavement damage inspection. Earlier work showed very promising results with 2D numerical models of damaged pavement. 1D and 2D heterogeneities were compared, both modelled in a 2D pavement world. In a 1D heterogeneous model energy leaks away to the sides, whereas in a 2D heterogeneous model rays can reflect and therefore still add to the signal reconstruction (see illustration). In the first case the amount of stationary points is strictly limited, while in the other case the amount of stationary points is very large. We extend these models to a 3D world and optimise an experimental configuration. The illustration originates from the journal article under submission 'Non-destructive pavement damage inspection by mono-static GPR without transmitting anything' by R. Feld, E.C. Slob, and J.W. Thorbecke. (a) 2D heterogeneous pavement model with three irregular-shaped misalignments between the base and subbase layer (marked by arrows). Mono-antenna B-scan positions are shown schematically. (b) Ideal output: a real source at the receiver's position. The difference w.r.t. the trace found in the middle is shown. (c) AC output: a virtual source at the receiver's position. There is a clear overlap with the ideal output.

Evaluation of clay content in soils for pavement engineering applications using GPR

NASA Astrophysics Data System (ADS)

Tosti, Fabio; Patriarca, Claudio; Benedetto, Andrea; Slob, Evert C.; Lambot, Sébastien

2013-04-01

Clay content significantly influences the mechanical behavior of soils, thereby playing an important role in many fields of applications such as civil engineering, geology and agriculture. In the area of pavement engineering, clay content in structural bearing courses of pavement frequently causes damages and defects, such as transversal and longitudinal cracks, or other faults. The main consequence is a lowering of both the road safety and operability, with the number of expected accidents increasing. In this study, ground-penetrating radar (GPR) laboratory tests were carried out to predict the clay amount in pavement structural layers under different clay and moisture conditions. GPR data processing is performed using two different methods. The first method is based on the Fresnel theory and focuses on the Rayleigh scattering of the radar waves. The approach is based on a different scattering of the various components of the frequency spectrum, mostly depending on both the soil texture and variation in soil moisture content. For the application of this method, we used a pulse radar with ground-coupled, 500 MHz centre-frequency antennas in a common offset, bistatic configuration. The transmitter and receiver were linked by optic fiber electronic modules. The second method is based on full-waveform inversion of the ultra wideband radar data. In particular, a specific radar-antenna electromagnetic model is used to filter out antenna effects and antenna-medium interactions from the raw radar data and retrieve the response of the soil only, expressed in terms of a layered medium Green's function. To estimate the medium geometrical and electrical values, an optimization inverse problem is formulated. For the application of that second method, we used a vector network analyzer (VNA) as continuous-wave stepped-frequency radar system to acquire data in the 500-3000 MHz frequency range. A doubled-ridged broadband horn antenna operating in far-field conditions was used as transmitter and receiver, and was connected to the radar using a high-quality coaxial cable. Typical road materials for subgrade and sub-base courses were used. In particular, three types of soils classified, respectively, as A1,A2,A3 by AASHTO were used and adequately compacted in electrically and hydraulically isolated boxes. A copper sheet was laid at the bottom of the experimental boxes to control the bottom boundary conditions in the electromagnetic model. Basically, two significant cases were considered for each soil type, taking into account the 0% and the 25% by weight of bentonite clay, respectively. Water was gradually added and GPR measurements were carried out for all moisture steps until the maximum saturation level was reached. Concerning the Rayleigh scattering method, analyses show a high consistency of the results with respect to our expectations. A negative correlation between the shift of the frequency spectrum peaks and the clay amount was demonstrated, by virtue of its strong hygroscopic properties. Similarly, the full-waveform inversion technique allowed to measure reliable electric parameters. Generally, different responses (e.g. electric conductivity and permittivity) of the 0% clay-member cases compared to those of the analogous clayey soil samples highlight the large potentiality of both methods for the detection of clay.

Neuregulin 1 Type II-ErbB Signaling Promotes Cell Divisions Generating Neurons from Neural Progenitor Cells in the Developing Zebrafish Brain.

PubMed

Sato, Tomomi; Sato, Fuminori; Kamezaki, Aosa; Sakaguchi, Kazuya; Tanigome, Ryoma; Kawakami, Koichi; Sehara-Fujisawa, Atsuko

2015-01-01

Post-mitotic neurons are generated from neural progenitor cells (NPCs) at the expense of their proliferation. Molecular and cellular mechanisms that regulate neuron production temporally and spatially should impact on the size and shape of the brain. While transcription factors such as neurogenin1 (neurog1) and neurod govern progression of neurogenesis as cell-intrinsic mechanisms, recent studies show regulatory roles of several cell-extrinsic or intercellular signaling molecules including Notch, FGF and Wnt in production of neurons/neural progenitor cells from neural stem cells/radial glial cells (NSCs/RGCs) in the ventricular zone (VZ). However, it remains elusive how production of post-mitotic neurons from neural progenitor cells is regulated in the sub-ventricular zone (SVZ). Here we show that newborn neurons accumulate in the basal-to-apical direction in the optic tectum (OT) of zebrafish embryos. While neural progenitor cells are amplified by mitoses in the apical ventricular zone, neurons are exclusively produced through mitoses of neural progenitor cells in the sub-basal zone, later in the sub-ventricular zone, and accumulate apically onto older neurons. This neurogenesis depends on Neuregulin 1 type II (NRG1-II)-ErbB signaling. Treatment with an ErbB inhibitor, AG1478 impairs mitoses in the sub-ventricular zone of the optic tectum. Removal of AG1478 resumes sub-ventricular mitoses without precedent mitoses in the apical ventricular zone prior to basal-to-apical accumulation of neurons, suggesting critical roles of ErbB signaling in mitoses for post-mitotic neuron production. Knockdown of NRG1-II impairs both mitoses in the sub-basal/sub-ventricular zone and the ventricular zone. Injection of soluble human NRG1 into the developing brain ameliorates neurogenesis of NRG1-II-knockdown embryos, suggesting a conserved role of NRG1 as a cell-extrinsic signal. From these results, we propose that NRG1-ErbB signaling stimulates cell divisions generating neurons from neural progenitor cells in the developing vertebrate brain.

Indirect diagnosis of pavement structural damages using surface GPR reflection techniques

NASA Astrophysics Data System (ADS)

Benedetto, A.; Pensa, S.

2007-06-01

The safety and operability of road networks is, in part, dependent on the quality of the pavement. It is known that pavements suffer from many different structural problems which can lead to damage to the pavement surface. To minimize the effect of these problems programmed policies for pavement management are required. Additionally a given local anomaly on the road surface can affect the safety of the road to various degrees according to the category of the road, so it is possible to set up different programmes of repair according to the different standards of road. Programmed policies for pavement management are required because of the wide structural damage which occurs to pavements during their normal operating life. This has consequences for the safety and operability of road networks. During the last decade, road networks suffered from great structural damage. The damage occurs for different reasons, such as the increasing traffic or the lack of means for routine maintenance. Many forms of damage, originating in the bottom layers are invisible until the pavement cracks. They depend on the infiltration of water and the presence of cohesive soil greatly reduces the bearing capacity of the sub-asphalt layers and underlying soils. On the basis of an in-depth literature review, an experimental survey with Ground Penetrating Radar (GPR) was carried out to calibrate the geophysical parameters and to validate the reliability of an indirect diagnostic method of pavement damage. The experiments were set on a pavement under which water was injected over a period of several hours. GPR travel time data were used to estimate the dielectric constant and the water content in the unbound aggregate layer, the variations in water content with time and particular areas where rate of infiltration decreases. A new methodology has been proposed to extract the hydraulic permittivity fields in sub-asphalt structural layers and soils from the moisture maps observed with GPR. It is effective at diagnosing the presence of clay or cohesive soil that compromises the bearing capacity of sub-base and induces damage.

Microstructures and Crystallographic Misorientation in Experimentally Deformed Natural Quartz Single Crystals

NASA Astrophysics Data System (ADS)

Thust, Anja; Heilbronner, Renée.; Stünitz, Holger

2010-05-01

Samples of natural milky quartz were deformed in a Griggs deformation apparatus at different confining pressures (700 MPa, 1000 MPa, 1500 MPa), with constant displacement rates of 1 * 10-6s-1, axial strains of 3 - 19%, and at a temperature of 900° C. The single crystal starting material contains a large number of H2O-rich fluid inclusions. Directly adjacent to the fluid inclusions the crystal is essentially dry (50-150H/106Si, determined by FTIR). The samples were cored from a narrow zone of constant 'milkyness' (i.e. same density of fluid inclusions) in a large single crystal in two different orientations (1) normal to one of the prism planes (⊥{m} orientation) and (2) 45° to and to (O+ orientation).During attaining of the experimental P and T conditions, numerous fluid inclusions decrepitate by cracking. Rapid crack healing produces regions of very small fluid inclusions ('wet' quartz domains). Only these regions are subsequently deformed by dislocation glide, dry quartz domains without cracking and decrepitation of fluid inclusions remain undeformed. Sample strain is not sufficient to cause recrystallization, so that deformation is restricted to dislocation glide. In experiments at lower temperatures (800, 700° C) or at lower strain rate (10-5s-1) there is abundant cracking and semi-brittle deformation, indicating that 900° C, (10-6s-1) represents the lower temperature end of crystal plastic deformation in these single crystals. Peak strengths (at 900° C) range between 150 and 250 MPa for most samples of both orientations. There is a trend of decreasing strength with increasing confining pressure, as described by Kronenberg and Tullis (1984) for quartzites, but the large variation in strength due to inhomogeneous sample strain precludes a definite analysis of the strength/pressure dependence in our single crystals. In the deformed samples, we can distinguish a number of microstructures and inferred different slip systems. In both orientations, deformation lamellae with a high optical relief appear in the usual sub-basal orientation; often they are associated with 'fluid inclusions trails', cracks or en echelon arrays. In ⊥{m} orientation, conjugate misorientation bands sub-parallel to the prism planes can be observed. The barreled shape of the samples can be explained by prism glide. Unfortunately, since prism glide does not affect the c-axis orientation it cannot be recognized on a c-axis orientation image. Nevertheless, changes in the c-axis orientation are observed locally, indicating either the activity of an additional slip system or a different deformation process (not specified yet). In O+ orientation, we observe the formation of internally kinked shear bands. They are up to 100 μm wide and oriented at α 90° w/r to the host c-axis, slightly oblique to the sense of shear. The width of the kinked domains is 20-40 μm and the average misorientation (β) is 5° . The dispersion of c-axis orientation with synthetic rotation of the c-axis is evidence of basal glide. References: Kronenberg, A.K. & Tullis, J. (1984): Flow strength of quartz aggregates: grain size and pressure effects due to hydrolytic weakening. JGR Vol. 89, 4281-4281.

Engineering geology studies in the National Petroleum Reserve, Alaska

USGS Publications Warehouse

Kachadoorian, Reuben; Crory, F.E.

1984-01-01

Engineering geology studies were conducted in direct support of the exploration program in the National Petroleum Reserve, Alaska. The studies included laboratory and field tests and observations to address design and construction problems of airfields, roads, drill pads and foundations, and to evaluate their actual performance. Permafrost containing large amounts of near surface ground ice as wedges, masses, and intergranular ice, required that all construction activity not disturb the thermal regime of the ground surface, which could lead to thaw of permafrost and ground subsidence. Summer activity, therefore was not allowable, yet the winter climate was so harsh that winter work was slow and inefficient. To allow summer operations at well sites planned for all year activity, it was necessary to adapt existing techniques for arctic construction and to devise new ones. The design and construction of facilities at the deep exploration wells at Inigok, Tunalik, and Lisburne posed the greatest challenge. These sites, requiring a year or more to drill, could only be attempted if continuous access to drilling and logistic supplies could be assured throughout the year, including the possibility of bringing in another drill rig, in the event of a blowout. Thus all-seasons airstrips were required at these wells. Sufficient quantities of local gravel were not readily available at the Inigok and Tunalik sites to construct the airstrips with the required 6 feet or more of gravel to prevent the underlying permafrost from thawing. Therefore, insulation was used to maintain the subbase of local sands in a continuously frozen state, which in turn was overlain by 15 inches of gravel or sandy gravel. Tests at the U.S. Army Waterways Experimental Station defined the minimum thickness of gravel required above the insulation to provide the desired bearing capacity for the C-130 type aircraft without crushing the insulation. Field testing also included the evaluation of another design option, using military landing mat underlain by insulation. Temperature recording devices were installed beneath the landing mat test sections, insulated runways, roads, drill pads, and reserve pits, to monitor the actual conditions and confirm the design assumptions. Investigations of thaw-settlement, erosion, and revegetation of all areas affected by construction were also conducted in anticipation of abandoning the sites, or, upgrading the facilities in the event the design life was extended.

Dry eye disease after refractive surgery: comparative outcomes of small incision lenticule extraction versus LASIK.

PubMed

Denoyer, Alexandre; Landman, Elise; Trinh, Liem; Faure, Jean-François; Auclin, François; Baudouin, Christophe

2015-04-01

To compare small incision lenticule extraction (SMILE) versus LASIK for post-refractive dry eye disease. Prospective, comparative, nonrandomized clinical study. Thirty patients scheduled for bilateral myopic SMILE and 30 age-, sex-, and refraction-matched patients scheduled for bilateral myopic LASIK were enrolled and followed for 6 months after the surgery. Complete evaluation of dry eye disease was performed at 1 and 6 months postoperatively, which included vision-related quality of life (Ocular Surface Disease Index [OSDI]), clinical examinations (tear film breakup time [TBUT], Schirmer I test, corneal staining), and tear osmolarity measurements, together with an overall severity score. Function and morphology of the corneal innervation were evaluated by corneal esthesiometry and subbasal nerve imaging using in vivo confocal microscopy (IVCM). Overall analysis of dry eye disease and corneal innervation. High incidence of mild to moderate dry eye disease was observed in both groups 1 month postoperatively, which remained significantly higher in the LASIK group than in the SMILE group 6 months after surgery (overall severity score [0-4]: 1.2±1.1 vs. 0.2±0.4, respectively, P < 0.01), leading to more frequent use of tear substitutes over the long term. Corneal sensitivity was better in SMILE than in LASIK eyes 1 month postoperatively (3.5±1.79 vs. 2.45±2.48, respectively, P < 0.01) and then recovered to statistically similar values at 6 months. Corneal nerve density, number of long fibers, and branchings as assessed by IVCM were significantly higher in the SMILE group compared with the LASIK group 1 and 6 months after surgery. Corneal sensitivity was negatively correlated with dry eye-related corneal damage (R² = 0.48, P < 0.01), and the long fiber nerve density was independently correlated with the OSDI score (R² = 0.50, P < 0.01) and the Schirmer test (R² = 0.21, P < 0.01) 6 months postoperatively. The SMILE procedure has a less pronounced impact on the ocular surface and corneal innervation compared with LASIK, further reducing the incidence of dry eye disease and subsequent degradation in quality of life after refractive surgery. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

USE AND KNOWLEDGE ON THE INFORMATION TECHNOLOGIES IN MEDICAL EDUCATION -BOSNIAN AND HERZEGOVINIAN EXPERIENCE.

PubMed

Masic, Izet; Begic, Edin; Begic, Nedim

2016-04-01

Information technologies (IT) are becoming a tool without which further education of both medical students and doctors would not be possible. The aim of this paper was to analyze the use of IT in the prism of two systems, the old system and the Bologna system. Answers from questionnaires from total of 459 students (2012/13-2015/16 generation) were analyzed. The presence of large number of female students, in both systems is significant (p <0.05). About 92% of students of the old system and 98% of students of the Bologna system use computer in everyday work (only 36% of old system and 47% of the Bologna system are using "faculties" computers). The computer is used for entertainment, education, information (via Internet) and for communication (e-mail, chat, social networks) (68.5% of the old system and 84% of students of the Bologna system have chosen all 4 offered answers). MS Word and MS Power Point are significantly more used compared to the use of MS Excel in both systems (p <0.05). The knowledge necessary to use their computers student of both systems have acquired through individual work. Students feel that they need to improve knowledge of the treatment of sub-base (76% of students of the old system and 62% of students of the Bologna system). Having analyzed the generation of 2015/16, 84.5% of students of the Bologna system and 75% of students of the old system used smartphones or tablets. The purpose of using a smartphone is, in most cases for accessing the social networks. 77.4% of smartphone users of the Bologna system, or 73.3% of the users of the old system have installed an application from the medical field. We analyzed the opinions of the availability of online course content and the degree of computerization of the study process and the possibility of electronic access to the literature - the results are not at the appropriate level. Education in software solutions that are connected to databases processing, must be imperative in reform of the teaching process. IT can only improve the teaching process, the organization of the education system in most eminent universities is undeniably linked to information technologies.

Control of tick infestations and pathogen prevalence in cattle and sheep farms vaccinated with the recombinant Subolesin-Major Surface Protein 1a chimeric antigen

PubMed Central

2014-01-01

Background Despite the use of chemical acaricides, tick infestations continue to affect animal health and production worldwide. Tick vaccines have been proposed as a cost-effective and environmentally friendly alternative for tick control. Vaccination with the candidate tick protective antigen, Subolesin (SUB), has been shown experimentally to be effective in controlling vector infestations and pathogen infection. Furthermore, Escherichia coli membranes containing the chimeric antigen composed of SUB fused to Anaplasma marginale Major Surface Protein 1a (MSP1a) (SUB-MSP1a) were produced using a simple low-cost process and proved to be effective for the control of cattle tick, Rhipicephalus (Boophilus) microplus and R. annulatus infestations in pen trials. In this research, field trials were conducted to characterize the effect of vaccination with SUB-MSP1a on tick infestations and the prevalence of tick-borne pathogens in a randomized controlled prospective study. Methods Two cattle and two sheep farms with similar geographical locations and production characteristics were randomly assigned to control and vaccinated groups. Ticks were collected, counted, weighed and classified and the prevalence of tick-borne pathogens at the DNA and serological levels were followed for one year prior to and 9 months after vaccination. Results Both cattle and sheep developed antibodies against SUB in response to vaccination. The main effect of the vaccine in cattle was the 8-fold reduction in the percent of infested animals while vaccination in sheep reduced tick infestations by 63%. Female tick weight was 32-55% lower in ticks collected from both vaccinated cattle and sheep when compared to controls. The seroprevalence of Babesia bigemina was lower by 30% in vaccinated cattle, suggesting a possible role for the vaccine in decreasing the prevalence of this tick-borne pathogen. The effect of the vaccine in reducing the frequency of one A. marginale msp4 genotype probably reflected the reduction in the prevalence of a tick-transmitted strain as a result of the reduction in the percent of tick-infested cattle. Conclusions These data provide evidence of the dual effect of a SUB-based vaccine for controlling tick infestations and pathogen infection/transmission and provide additional support for the use of the SUB-MSP1a vaccine for tick control in cattle and sheep. PMID:24398155

Control of tick infestations and pathogen prevalence in cattle and sheep farms vaccinated with the recombinant Subolesin-Major Surface Protein 1a chimeric antigen.

PubMed

Torina, Alessandra; Moreno-Cid, Juan A; Blanda, Valeria; Fernández de Mera, Isabel G; de la Lastra, José M Pérez; Scimeca, Salvatore; Blanda, Marcellocalogero; Scariano, Maria Elena; Briganò, Salvatore; Disclafani, Rosaria; Piazza, Antonio; Vicente, Joaquín; Gortázar, Christian; Caracappa, Santo; Lelli, Rossella Colomba; de la Fuente, José

2014-01-08

Despite the use of chemical acaricides, tick infestations continue to affect animal health and production worldwide. Tick vaccines have been proposed as a cost-effective and environmentally friendly alternative for tick control. Vaccination with the candidate tick protective antigen, Subolesin (SUB), has been shown experimentally to be effective in controlling vector infestations and pathogen infection. Furthermore, Escherichia coli membranes containing the chimeric antigen composed of SUB fused to Anaplasma marginale Major Surface Protein 1a (MSP1a) (SUB-MSP1a) were produced using a simple low-cost process and proved to be effective for the control of cattle tick, Rhipicephalus (Boophilus) microplus and R. annulatus infestations in pen trials. In this research, field trials were conducted to characterize the effect of vaccination with SUB-MSP1a on tick infestations and the prevalence of tick-borne pathogens in a randomized controlled prospective study. Two cattle and two sheep farms with similar geographical locations and production characteristics were randomly assigned to control and vaccinated groups. Ticks were collected, counted, weighed and classified and the prevalence of tick-borne pathogens at the DNA and serological levels were followed for one year prior to and 9 months after vaccination. Both cattle and sheep developed antibodies against SUB in response to vaccination. The main effect of the vaccine in cattle was the 8-fold reduction in the percent of infested animals while vaccination in sheep reduced tick infestations by 63%. Female tick weight was 32-55% lower in ticks collected from both vaccinated cattle and sheep when compared to controls. The seroprevalence of Babesia bigemina was lower by 30% in vaccinated cattle, suggesting a possible role for the vaccine in decreasing the prevalence of this tick-borne pathogen. The effect of the vaccine in reducing the frequency of one A. marginale msp4 genotype probably reflected the reduction in the prevalence of a tick-transmitted strain as a result of the reduction in the percent of tick-infested cattle. These data provide evidence of the dual effect of a SUB-based vaccine for controlling tick infestations and pathogen infection/transmission and provide additional support for the use of the SUB-MSP1a vaccine for tick control in cattle and sheep.

Window into the Caledonian orogen: Structure of the crust beneath the East Shetland platform, United Kingdom

USGS Publications Warehouse

McBride, J.H.; England, R.W.

1999-01-01

Reprocessing and interpretation of commercial and deep seismic reflection data across the East Shetland platform and its North Sea margin provide a new view of crustal subbasement structure beneath a poorly known region of the British Caledonian orogen. The East Shetland platform, east of the Great Glen strike-slip fault system, is one of the few areas of the offshore British Caledonides that remained relatively insulated from the Mesozoic and later rifting that involved much of the area around the British Isles, thus providing an "acoustic window" into the deep structure of the orogen. Interpretation of the reflection data suggests that the crust beneath the platform retains a significant amount of its original Caledonian and older architecture. The upper to middle crust is typically poorly reflective except for individual prominent dipping reflectors with complex orientations that decrease in dip with depth and merge with a lower crustal layer of high reflectivity. The three-dimensional structural orientation of the reflectors beneath the East Shetland platform is at variance with Caledonian reflector trends observed elsewhere in the Caledonian orogen (e.g., north of the Scottish mainland), emphasizing the unique tectonic character of this part of the orogen. Upper to middle crustal reflectors are interpreted as Caledonian or older thrust surfaces that were possibly reactivated by Devonian extension associated with post-Caledonian orogenic collapse. The appearance of two levels of uneven and diffractive (i.e., corrugated) reflectivity in the lower crust, best developed on east-west-oriented profiles, is characteristic of the East Shetland platform. However, a north-south-oriented profile reveals an interpreted south-vergent folded and imbricated thrust structure in the lower crust that appears to be tied to the two levels of corrugated reflectivity on the east-west profiles. A thrust-belt origin for lower crustal reflectivity would explain its corrugated appearance. Regional seismic velocity models derived from refraction data suggest that this reflectivity correlates with a continuous lower crustal layer that has an intermediate seismic velocity. The lower crustal reflectivity is determined to be older than Mesozoic age by the bending down and truncation of the two reflectivity levels at the western margin of the North Sea Viking graben by a major mantle reflector inferred to be associated with Mesozoic rifting. The results of this study are thus in contrast with orthodox interpretations of the reflective layered lower crust as being caused by mantle-derived igneous intrusion or by deformation fabrics associated with stretching in response to continental rifting.

The Search for Organics (δ 13C and δ 15N) Throughout a Sub Basement Fossil Soil (Ocean Drilling Program, Leg 197): Implications for Earth/Mars deep subsurface

NASA Astrophysics Data System (ADS)

Bonaccorsi, R.

2003-12-01

Detecting organics buried deep beneath the surface of a planet is a fundamental step to constrain the presence and evolution of life on a planet. This is especially true for Mars with barren-life surface owing to extreme settings (UV flux, P atm and T). However, organics and/or viable microbes could still preserved at some deeper locations on Mars [e.g.,1]. This work presents the first nitrogen isotope (δ 15N) data for deeply buried Early Tertiary fossil soil Unit (Core 197-1206A-40R; 307.5-309.9 mbsf). They were RCB-cored from the volcanic basement at Site 1206 (Koko Seamount, ~34° 56' N; ~172° 9' E) during the ODP Leg 197 (Emperor Seamounts, north Pacific). These Fe-rich, palagonite-bearing soils were formed on the top of subsiding atolls and subsequently buried by lava flows in a near shore environment {[2]}. Burial rates higher than average subsidence rates ensured the isolation of these fossil soils in a present-day sub-basement setting and their decoupling from the ocean and the atmosphere for likely >54 Ma. Leg 197 soils contain very low, but reliable amounts of total organic carbon (TOC=0.01-0.12 %wt, +/- 0.02%, N=36; {[2-3]}). The single fossil soil unit has stable isotope values more negative (i.e., δ 13C-org. = -25.3 ‰ to -26.2‰ ;{[4]}) and δ 15N-tot = -9.5‰ to +2.5‰ than those of exposed Hawaiian counterparts (i.e., δ 15N-tot = >=0‰ to +8.5‰ ). This isotopically lighter Ntot could be interpreted as bacterial fractionation throughout the N-cycle either occurred in the past (Early Eocene/Late Paleocene) and changing organic source (C-3, C-4-plants, bacterial) and N-cycle associated processes. However the existing data-set {[2-4]} need to be compared with microbiological data to establish the potential for these soils to serve as a suitable analog for a possible Mars near-surface/deep biosphere. {[1]}Mancinelli, R.L, 2000. Planet. Space Sci., 48:1035-1043; {[2]} Shipboard Scientific Party, 2002, Proc. ODP, Init. Repts. 197: College Station, TX; {[3]} Bonaccorsi, R., 2002. EOS Trans AGU, 83(47), Fall Meet. Suppl. Abstract;{[4]}Meyers, P.A., 1997. Org. Geochem., 27, 5/6:213-259.

Study of a rehabilitated road using GPR and FWD

NASA Astrophysics Data System (ADS)

Marecos, Vania; Fontul, Simona; de Lurdes Antunes, Maria; Solla, Mercedes; Pajewski, Lara

2017-04-01

This work focus on the structural evaluation of a rehabilitated road after the conclusion of the first phase of the improvement works. The activities developed in the study comprised the characterization of the pavement layers condition (before the application of the asphalt surface layer) and the prediction of the pavement bearing capacity (taking into account the contribution of the wearing course, to be placed in accordance with the project specifications). For this study two non-destructive tests (NDT) were combined: Falling Weight Deflectometer (FWD) and Ground Penetrating Radar (GPR). The original pavement was essentially composed by a granular layer treated with a bituminous emulsion. The main objectives of the rehabilitation works were the enlargement of the road platform in selected locations, with the construction of a new pavement, and also the reinforcement of the existing pavement to increase its bearing capacity. The FWD tests were performed to assess the bearing capacity of the pavement and were conducted along the outer wheel path, in both directions. The spacing between measurement points was 75 m and the applied impulse load was 50 kN. The results showed a great variability of the deflections measured along the section under study. A preliminary zonation of the pavement was carried out, and was latter adjusted based on the results of the GPR. To determine the thickness of the pavement layers a GPR survey was carried out using a 1.8 GHz antenna and a radar control unit SIR-20, both from GSSI. The GPR tests were performed continuously along the same line as the FWD tests. The GPR tests allowed for the identification of the different structures of the pavement, corresponding to the zones with the new pavement and the existing pavement with reinforcement. Some cores were extracted to calibrate the thickness of the GPR bituminous layers, to verify the conditions of adhesion between layers and also to perform laboratory tests to characterize the bituminous mixtures. Test pits were also carried out to calibrate the GPR thickness for the granular layers. It was concluded that the areas with higher deflections coincided with the new pavement areas. The GPR results showed that in the existing reinforced pavement zones the total thickness of the reinforcement layers were higher than design values. On the other hand, for the new pavement zones, it was observed lower thicknesses for the base and sub-base layers and also for the binder layer, in comparison with the design values. The results of the laboratory tests carried out on samples of the bituminous mixtures showed that, in general, those mixtures had percentages of bitumen and porosities above the expected values. Based on the tests carried out, pavement response models were established and their predictable load capacity was estimated. This abstract is a contribution to COST Action TU1208 Civil Engineering Applications of Ground Penetrating Radar.

Anatomy of a deep sub-surface ridge flank aquifer: The "Red Brick" Horizon in ODP Hole 1256D

NASA Astrophysics Data System (ADS)

Teagle, D. A.; Smith-Duque, C. E.; Harris, M.; Rutter, J.; Coggon, R. M.; Tominaga, M.; Alt, J.; Murphy, B.; Banerjee, N.

2012-12-01

Long-lived conductive heat flow deficits, near isothermal basement temperatures, and sedimentary pore water profiles from mid-ocean ridge flanks provide compelling arguments for the substantial lateral movement of seawater-derived fluids within the upper oceanic crust. However, there are few descriptions of zones within the oceanic basement for which there is strong evidence for sustained low temperature hydrothermal fluid flow and alteration. This paper describes a distinctive horizon of intense low temperature alteration encountered in ODP Hole 1256D. Hole 1256D, located on 15 million-year-old East Pacific Rise crust formed at a superfast spreading rate (>200 mm/yr) provides a reference section for fast spreading ocean crust and is the only well to sample a complete section of lavas, sheeted dikes, and into the upper most gabbros. The volcanic sequences at Hole 1256D are >800 m thick. The Red Brick horizon occurs at ~400 m sub-basement (msb) in massive and sheet flows that overly a ~30 m-thick zone of massive flows. These flows probably crystallized at the base of the ridge axial slope within a few 1000 meters of the ridge axis (Tominaga and Umino, 2010). The Red Brick horizon comprises a 50 cm-thick zone of massive, sparsely olivine-phyric microcrystalline basalt that is very strongly (80 to 90%) hydrothermally altered. Olivine, clinopyroxene, and plagioclase are replaced by beidellite, celadonite, K feldspar and iron oxyhydroxide, imparting blue-green and brick red colors to the rock. These secondary minerals plus quartz and carbonate also fill vugs and pore space. Compared to surrounding basalts that exhibit only background levels of low temperature alteration, the rocks of the Red Brick zone are strongly oxidized (Fe3+/FeTot >0.7), hydrated (>4 wt.%), and have highly elevated concentrations of alkali metals (K, Rb, Cs) and Mg. There are strong reductions in Si, Ca, Mn, Zn and Cu. Bulk rock oxygen isotope (δ18O ~8.5 to 9 per mil) indicate hydrothermal alteration at about 70 °C for a seawater-like fluid. 87Sr/86Sr is significantly elevated (0.7033 to 0.7045) compared to primary igneous values but still rock-dominated. The near complete mineral recrystallization should mean that Sr isotope ratios record the signature of the parent hydrothermal fluid. Intriguingly this range is much less radiogenic than our estimate for Site 1256 paleo-black smoker fluids (0.7051 to 0.7053) indicating that the altering fluids are not seawater-diluted black smoker fluids. The core pieces of the Red Brick zone can be confidently identified in the wireline geophysical measurements by integrating formation micro-scanner and gamma ray logs. The occurrence of intense alteration at the Red Brick horizon appears to result from the occurrence of an impermeable unit of massive basalt with few fractures directly below, that may have acted as a long term channel for the lateral flow of ridge flank hydrothermal fluids.

On-site inspections of pavement damages evolution using GPR

NASA Astrophysics Data System (ADS)

Tosti, Fabio; D'Amico, Fabrizio; Calvi, Alessandro; Benedetto, Andrea

2014-05-01

Ground-penetrating radar (GPR) is being increasingly used for pavements maintenance due to the wide range of applications spanning from physical to geometrical inspections, thereby allowing for a reliable diagnosis of the main causes of road structural damages. In this work, an off-ground GPR system was used to investigate a large-scale rural road network. Two sets of surveys were carried out in different time periods, with the main goals to i) localize the most critical sections; ii) monitor the evolution of previous damages and localize newborn deep faults, although not revealed at the pavement surface level; iii) analyze the causes of both evolution and emergence of faults by considering environmental and human factors. A 1-GHz GPR air-launched antenna was linked to an instrumented van for collecting data at traffic speed. Other support techniques (e.g. GPS data logger, odometer, HD video camera) were used for cross-checking,. Such centre frequency of investigation along with a 25-ns time window allow for a signal penetration of 900 mm, consistent with the deepest layer interfaces. The bottom of the array was 400 mm over the surface, with a minimum distance of 1200 mm from the van body. Scan length of maximum 10 km were provided for avoiding heavy computational loads. The rural road network was located in the District of Rieti, 100 km north from Rome, Italy, and mostly develops in a hilly and mountainous landscape. In most of the investigated roads, the carriageway consists in two lanes of 3.75 meters wide and two shoulders of 0.50 meters wide. A typical road section includes a HMA layer (65 mm average thickness), a base layer (100 mm average thickness), and a subbase layer (300 mm average thickness), as described by pavement design charts. The first set of surveys was carried out in two days at the beginning of spring in moderately dry conditions. Overall, 320-km-long inspections were performed in both travel directions, thereby showing a productivity of approximately 160 km/day at 40 km/h speed, on the average. After processing and first-checking, GPR profiles were divided into homogeneous sections according to the combination of different parameters (e.g. route analyzed, long distance conditions of regularity/irregularity in layers arrangement). In such context, a high consistency between surface damages, mismatches from the GPR scans, and boundary environmental conditions was demonstrated. In addition, deep mismatches were detected even for early-stage or unrevealed faults. The second set of surveys was carried out in autumn in high humidity conditions, due to recent rainfalls. 160 km of relevant routes from the same road network were investigated. Results showed a high consistency with those collected during the first-stage of surveys. Minor changes were found in those sections with low traffic loads (e.g. farther away from the biggest town of Rieti), whereas major mismatches were detected in wetlands (e.g. close to rivers), work zones, and nearby those sections already deeply damaged in the past. This work benefited from networking activities carried out within the EU funded COST Action TU1208 'Civil Engineering Applications of Ground Penetrating Radar'.

Method for forming materials

DOEpatents

Tolle, Charles R [Idaho Falls, ID; Clark, Denis E [Idaho Falls, ID; Smartt, Herschel B [Idaho Falls, ID; Miller, Karen S [Idaho Falls, ID

2009-10-06

A material-forming tool and a method for forming a material are described including a shank portion; a shoulder portion that releasably engages the shank portion; a pin that releasably engages the shoulder portion, wherein the pin defines a passageway; and a source of a material coupled in material flowing relation relative to the pin and wherein the material-forming tool is utilized in methodology that includes providing a first material; providing a second material, and placing the second material into contact with the first material; and locally plastically deforming the first material with the material-forming tool so as mix the first material and second material together to form a resulting material having characteristics different from the respective first and second materials.

Rare earth-doped materials with enhanced thermoelectric figure of merit

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

Venkatasubramanian, Rama; Cook, Bruce Allen; Levin, Evgenii M.

A thermoelectric material and a thermoelectric converter using this material. The thermoelectric material has a first component including a semiconductor material and a second component including a rare earth material included in the first component to thereby increase a figure of merit of a composite of the semiconductor material and the rare earth material relative to a figure of merit of the semiconductor material. The thermoelectric converter has a p-type thermoelectric material and a n-type thermoelectric material. At least one of the p-type thermoelectric material and the n-type thermoelectric material includes a rare earth material in at least one ofmore » the p-type thermoelectric material or the n-type thermoelectric material.« less

Microwave impregnation of porous materials with thermal energy storage materials

DOEpatents

Benson, David K.; Burrows, Richard W.

1993-01-01

A method for impregnating a porous, non-metallic construction material with a solid phase-change material is described. The phase-change material in finely divided form is spread onto the surface of the porous material, after which the porous material is exposed to microwave energy for a time sufficient to melt the phase-change material. The melted material is spontaneously absorbed into the pores of the porous material. A sealing chemical may also be included with the phase-change material (or applied subsequent to the phase-change material) to seal the surface of the porous material. Fire retardant chemicals may also be included with the phase-change materials. The treated construction materials are better able to absorb thermal energy and exhibit increased heat storage capacity.

Microwave impregnation of porous materials with thermal energy storage materials

DOEpatents

Benson, D.K.; Burrows, R.W.

1993-04-13

A method for impregnating a porous, non-metallic construction material with a solid phase-change material is described. The phase-change material in finely divided form is spread onto the surface of the porous material, after which the porous material is exposed to microwave energy for a time sufficient to melt the phase-change material. The melted material is spontaneously absorbed into the pores of the porous material. A sealing chemical may also be included with the phase-change material (or applied subsequent to the phase-change material) to seal the surface of the porous material. Fire retardant chemicals may also be included with the phase-change materials. The treated construction materials are better able to absorb thermal energy and exhibit increased heat storage capacity.

Method and apparatus for biological material separation

DOEpatents

Robinson, Donna L.

2005-05-10

There has been invented an apparatus comprising a separation barrier for excluding denser cell materials from less dense cell materials after centrifuging of the cells so that selected materials can be withdrawn from the less dense cell materials without inclusion of the denser cell materials or clogging of sampling equipment with denser cell materials. Cells from which selected material is to be withdrawn are centrifuged, either as cells or cells in media. Once the denser cell materials are isolated in a layer by centrifugal force, an invention screen or seive is submerged in the less dense cell material to a level above the layer of denser cell materials to isolate the denser cell materials from the less dense cell materials, preventing mixing of the denser cell materials back into the less dense cell materials when the cells or the cells in media are no longer being centrifuged and to prevent clogging of sampling equipment with denser cell materials. In a particularly useful application of the invention method and apparatus, plasmid DNA can be withdrawn from less dense cell materials without contamination or interference with denser cell materials.

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

Tooker, Angela C.; Felix, Sarah H.; Pannu, Satinderpall S.

A neural interface includes a first dielectric material having at least one first opening for a first electrical conducting material, a first electrical conducting material in the first opening, and at least one first interconnection trace electrical conducting material connected to the first electrical conducting material. A stiffening shank material is located adjacent the first dielectric material, the first electrical conducting material, and the first interconnection trace electrical conducting material.

Space Materials Handbook. 3rd; ed.

NASA Technical Reports Server (NTRS)

Rittenhouse, John B.; Singletary, John B.

1969-01-01

This edition is the result of an extensive revision and reworking of the second edition of the Space Materials Handbook along with the incorporation of entirely new subject matter coverage and new materials data. All of the most significant material, phenomena, properties, and principles covered in the original Handbook are presented and expanded in this revised and updated version. However, treatment of theoretical aspects has been condensed in order that more emphasis could be placed on the extensive new materials knowledge and data obtained from the design and successful launching of a wide variety of space systems. The handbook is organized into four parts, namely: space environment, effect of space environment on materials, materials in space, and biological interaction with spacecraft materials. Information on mechanical, physical, and chemical properties and characteristics is given for a wide variety of metallic and nonmetallic materials. The effects of natural and induced environments on materials are appraised. Materials categories include coverage of thermal control materials, optical materials, adhesives, organic structural materials, inorganic structural materials, electronic components and materials, materials for sealing applications, and lubrication materials. In addition, a comprehensive multiple citation index is incorporated which gives ready access to information on specific subject areas with regard to their locations within the Handbook.

Nuclear reactor target assemblies, nuclear reactor configurations, and methods for producing isotopes, modifying materials within target material, and/or characterizing material within a target material

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

Toth, James J.; Wall, Donald; Wittman, Richard S.

Target assemblies are provided that can include a uranium-comprising annulus. The assemblies can include target material consisting essentially of non-uranium material within the volume of the annulus. Reactors are disclosed that can include one or more discrete zones configured to receive target material. At least one uranium-comprising annulus can be within one or more of the zones. Methods for producing isotopes within target material are also disclosed, with the methods including providing neutrons to target material within a uranium-comprising annulus. Methods for modifying materials within target material are disclosed as well as are methods for characterizing material within a targetmore » material.« less

EDITORIAL: Adaptive and Active Materials: Selected Papers from the ASME 2008 Conference on Smart Materials, Adaptive Structures and Intelligent Systems (SMASIS 08) (Maryland, USA, 28-30 October 2008) Adaptive and Active Materials: Selected Papers from the ASME 2008 Conference on Smart Materials, Adaptive Structures and Intelligent Systems (SMASIS 08) (Maryland, USA, 28-30 October 2008)

NASA Astrophysics Data System (ADS)

Lynch, Christopher

2009-10-01

The rapid development of the field of Smart Materials, Adaptive Structures, and Materials Systems led the Aerospace Division ASMS TC to launch the new annual SMASIS conference in 2008. The conference focuses on the multi-disciplinary challenges of developing new multifunctional materials and implementing them in advanced systems. The research spans length scales from nano-structured materials to civil, air, and space structures. The first conference consisted of six symposia, each focusing on a different research area. This special issue of Smart Materials and Structures summarizes some of the top research presented at the 2008 SMASIS conference in the materials-focused symposia. These symposia focused on the behavior and mechanics of active materials, on multifunctional materials, and on bio-inspired materials. The behavior and mechanics of active materials is an approach that combines observed material behavior with mechanism-based models that not only give insight into the observed behavior, but guide the development of new materials. This approach has been applied to shape memory metals and polymers, ferroelectrics, ferromagnetics, and recently to multiferroic materials, and has led to considerable improvements in our understanding of multi-field phenomena. Multifunctional materials are the next generation of active materials. These materials include structural, sensing, and actuation components integrated into a material system. A natural extension of multifunctional materials is a new class of bio-inspired materials. Bio-inspired materials range from detailed bio-mimicry of sensing and self healing materials to nano and microstructures that take advantage of features observed in biological systems. The Editors would like to express their sincere thanks to all of the authors for their contributions to this special issue on 'Adaptive and Active Materials' for Smart Materials and Structures. We convey our gratitude to all of the reviewers for their time and dedication. We thank IOP Publishing for their support and encouragement of this special issue and the staff for their special attention and timely response.

Processing of insulators and semiconductors

DOEpatents

Quick, Nathaniel R.; Joshi, Pooran C.; Duty, Chad Edward; Jellison, Jr., Gerald Earle; Angelini, Joseph Attilio

2015-06-16

A method is disclosed for processing an insulator material or a semiconductor material. The method includes pulsing a plasma lamp onto the material to diffuse a doping substance into the material, to activate the doping substance in the material or to metallize a large area region of the material. The method may further include pulsing a laser onto a selected region of the material to diffuse a doping substance into the material, to activate the doping substance in the material or to metallize a selected region of the material.

Methods and system for controlled laser-driven explosive bonding

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

Rubenchik, Alexander M.; Farmer, Joseph C.; Hackel, Lloyd

A technique for bonding two dissimilar materials includes positioning a second material over a first material at an oblique angle and applying a tamping layer over the second martial. A laser beam is directed at the second material that generates a plasma at the location of impact on the second material. The plasma generates pressure that accelerates a portion of the second material to a very high velocity and towards the first material. The second material impacts the first material causing bonding of the two materials.

Modeling of materials supply, demand and prices

NASA Technical Reports Server (NTRS)

1982-01-01

The societal, economic, and policy tradeoffs associated with materials processing and utilization, are discussed. The materials system provides the materials engineer with the system analysis required for formulate sound materials processing, utilization, and resource development policies and strategies. Materials system simulation and modeling research program including assessments of materials substitution dynamics, public policy implications, and materials process economics was expanded. This effort includes several collaborative programs with materials engineers, economists, and policy analysts. The technical and socioeconomic issues of materials recycling, input-output analysis, and technological change and productivity are examined. The major thrust areas in materials systems research are outlined.

Transporting particulate material

DOEpatents

Aldred, Derek Leslie [North Hollywood, CA; Rader, Jeffrey A [North Hollywood, CA; Saunders, Timothy W [North Hollywood, CA

2011-08-30

A material transporting system comprises a material transporting apparatus (100) including a material transporting apparatus hopper structure (200, 202), which comprises at least one rotary transporting apparatus; a stationary hub structure (900) constraining and assisting the at least one rotary transporting apparatus; an outlet duct configuration (700) configured to permit material to exit therefrom and comprising at least one diverging portion (702, 702'); an outlet abutment configuration (800) configured to direct material to the outlet duct configuration; an outlet valve assembly from the material transporting system venting the material transporting system; and a moving wall configuration in the material transporting apparatus capable of assisting the material transporting apparatus in transporting material in the material transporting system. Material can be moved from the material transporting apparatus hopper structure to the outlet duct configuration through the at least one rotary transporting apparatus, the outlet abutment configuration, and the outlet valve assembly.

Screening combinatorial arrays of inorganic materials with spectroscopy or microscopy

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

2004-02-03

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial synthesis of novel materials

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

1999-01-01

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial sythesis of organometallic materials

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

2002-07-16

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Polymer arrays from the combinatorial synthesis of novel materials

DOEpatents

Schultz, Peter G.; Xiang, Xiao-Dong; Goldwasser, Isy; Briceno, Gabriel; Sun, Xiao-Dong

2004-09-21

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial synthesis of novel materials

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

2002-02-12

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Preparation and screening of crystalline inorganic materials

DOEpatents

Schultz, Peter G [La Jolla, CA; Xiang, Xiaodong [Danville, CA; Goldwasser, Isy [Palo Alto, CA; Brice{hacek over }o, Gabriel; Sun, Xiao-Dong [Fremont, CA; Wang, Kai-An [Cupertino, CA

2008-10-28

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial synthesis of novel materials

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

1999-12-21

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial synthesis of novel materials

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

2001-01-01

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial screening of inorganic and organometallic materials

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

2002-01-01

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Preparation and screening of crystalline zeolite and hydrothermally-synthesized materials

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy; Briceno, Gabriel; Sun, Xiao-Dong; Wang, Kai-An

2005-03-08

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial synthesis of inorganic or composite materials

DOEpatents

Goldwasser, Isy; Ross, Debra A.; Schultz, Peter G.; Xiang, Xiao-Dong; Briceno, Gabriel; Sun, Xian-Dong; Wang, Kai-An

2010-08-03

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials or, alternatively, allowing the components to interact to form at least two different materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, nonbiological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Ceramic/metal and A15/metal superconducting composite materials exploiting the superconducting proximity effect and method of making the same

DOEpatents

Holcomb, Matthew J.

1999-01-01

A composite superconducting material made of coated particles of ceramic superconducting material and a metal matrix material. The metal matrix material fills the regions between the coated particles. The coating material is a material that is chemically nonreactive with the ceramic. Preferably, it is silver. The coating serves to chemically insulate the ceramic from the metal matrix material. The metal matrix material is a metal that is susceptible to the superconducting proximity effect. Preferably, it is a NbTi alloy. The metal matrix material is induced to become superconducting by the superconducting proximity effect when the temperature of the material goes below the critical temperature of the ceramic. The material has the improved mechanical properties of the metal matrix material. Preferably, the material consists of approximately 10% NbTi, 90% coated ceramic particles (by volume). Certain aspects of the material and method will depend upon the particular ceramic superconductor employed. An alternative embodiment of the invention utilizes A15 compound superconducting particles in a metal matrix material which is preferably a NbTi alloy.

Flexible neural interfaces with integrated stiffening shank

DOEpatents

Tooker, Angela C.; Felix, Sarah H.; Pannu, Satinderpall S.; Shah, Kedar G.; Sheth, Heeral; Tolosa, Vanessa

2016-07-26

A neural interface includes a first dielectric material having at least one first opening for a first electrical conducting material, a first electrical conducting material in the first opening, and at least one first interconnection trace electrical conducting material connected to the first electrical conducting material. A stiffening shank material is located adjacent the first dielectric material, the first electrical conducting material, and the first interconnection trace electrical conducting material.

Phase-change materials handbook

NASA Technical Reports Server (NTRS)

Hale, D. V.; Hoover, M. J.; Oneill, M. J.

1972-01-01

Handbook describes relationship between phase-change materials and more conventional thermal control techniques and discusses materials' space and terrestrial applications. Material properties of most promising phase-change materials and purposes and uses of metallic filler materials in phase-change material composites are provided.

49 CFR 173.459 - Mixing of fissile material packages with non-fissile or fissile-excepted material packages.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 2 2012-10-01 2012-10-01 false Mixing of fissile material packages with non... (Radioactive) Materials § 173.459 Mixing of fissile material packages with non-fissile or fissile-excepted material packages. Mixing of fissile material packages with other types of Class 7 (radioactive) materials...

49 CFR 173.459 - Mixing of fissile material packages with non-fissile or fissile-excepted material packages.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 2 2013-10-01 2013-10-01 false Mixing of fissile material packages with non... (Radioactive) Materials § 173.459 Mixing of fissile material packages with non-fissile or fissile-excepted material packages. Mixing of fissile material packages with other types of Class 7 (radioactive) materials...

49 CFR 173.459 - Mixing of fissile material packages with non-fissile or fissile-excepted material packages.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 2 2011-10-01 2011-10-01 false Mixing of fissile material packages with non... (Radioactive) Materials § 173.459 Mixing of fissile material packages with non-fissile or fissile-excepted material packages. Mixing of fissile material packages with other types of Class 7 (radioactive) materials...

49 CFR 173.459 - Mixing of fissile material packages with non-fissile or fissile-excepted material packages.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Mixing of fissile material packages with non... (Radioactive) Materials § 173.459 Mixing of fissile material packages with non-fissile or fissile-excepted material packages. Mixing of fissile material packages with other types of Class 7 (radioactive) materials...

49 CFR 173.459 - Mixing of fissile material packages with non-fissile or fissile-excepted material packages.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 2 2014-10-01 2014-10-01 false Mixing of fissile material packages with non... (Radioactive) Materials § 173.459 Mixing of fissile material packages with non-fissile or fissile-excepted material packages. Mixing of fissile material packages with other types of Class 7 (radioactive) materials...

10 CFR 35.1000 - Other medical uses of byproduct material or radiation from byproduct material.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false Other medical uses of byproduct material or radiation from... MATERIAL Other Medical Uses of Byproduct Material or Radiation From Byproduct Material § 35.1000 Other medical uses of byproduct material or radiation from byproduct material. A licensee may use byproduct...

10 CFR 35.1000 - Other medical uses of byproduct material or radiation from byproduct material.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Other medical uses of byproduct material or radiation from... MATERIAL Other Medical Uses of Byproduct Material or Radiation From Byproduct Material § 35.1000 Other medical uses of byproduct material or radiation from byproduct material. A licensee may use byproduct...

10 CFR 35.1000 - Other medical uses of byproduct material or radiation from byproduct material.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false Other medical uses of byproduct material or radiation from... MATERIAL Other Medical Uses of Byproduct Material or Radiation From Byproduct Material § 35.1000 Other medical uses of byproduct material or radiation from byproduct material. A licensee may use byproduct...

10 CFR 35.1000 - Other medical uses of byproduct material or radiation from byproduct material.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Other medical uses of byproduct material or radiation from... MATERIAL Other Medical Uses of Byproduct Material or Radiation From Byproduct Material § 35.1000 Other medical uses of byproduct material or radiation from byproduct material. A licensee may use byproduct...

10 CFR 35.1000 - Other medical uses of byproduct material or radiation from byproduct material.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Other medical uses of byproduct material or radiation from... MATERIAL Other Medical Uses of Byproduct Material or Radiation From Byproduct Material § 35.1000 Other medical uses of byproduct material or radiation from byproduct material. A licensee may use byproduct...

Commentary: The Materials Project: A materials genome approach to accelerating materials innovation

NASA Astrophysics Data System (ADS)

Jain, Anubhav; Ong, Shyue Ping; Hautier, Geoffroy; Chen, Wei; Richards, William Davidson; Dacek, Stephen; Cholia, Shreyas; Gunter, Dan; Skinner, David; Ceder, Gerbrand; Persson, Kristin A.

2013-07-01

Accelerating the discovery of advanced materials is essential for human welfare and sustainable, clean energy. In this paper, we introduce the Materials Project (www.materialsproject.org), a core program of the Materials Genome Initiative that uses high-throughput computing to uncover the properties of all known inorganic materials. This open dataset can be accessed through multiple channels for both interactive exploration and data mining. The Materials Project also seeks to create open-source platforms for developing robust, sophisticated materials analyses. Future efforts will enable users to perform ``rapid-prototyping'' of new materials in silico, and provide researchers with new avenues for cost-effective, data-driven materials design.

Materials @ LANL: Solutions for National Security Challenges

NASA Astrophysics Data System (ADS)

Teter, David

2012-10-01

Materials science activities impact many programmatic missions at LANL including nuclear weapons, nuclear energy, renewable energy, global security and nonproliferation. An overview of the LANL materials science strategy and examples of materials science programs will be presented. Major materials leadership areas are in materials dynamics, actinides and correlated electron materials, materials in radiation extremes, energetic materials, integrated nanomaterials and complex functional materials. Los Alamos is also planning a large-scale, signature science facility called MaRIE (Matter Radiation Interactions in Extremes) to address in-situ characterization of materials in dynamic and radiation environments using multiple high energy probes. An overview of this facility will also be presented.

Advanced Materials for Exploration Task Research Results

NASA Technical Reports Server (NTRS)

Cook, M. B. (Compiler); Murphy, K. L.; Schneider, T.

2008-01-01

The Advanced Materials for Exploration (AME) Activity in Marshall Space Flight Center s (MSFC s) Exploration Science and Technology Directorate coordinated activities from 2001 to 2006 to support in-space propulsion technologies for future missions. Working together, materials scientists and mission planners identified materials shortfalls that are limiting the performance of long-term missions. The goal of the AME project was to deliver improved materials in targeted areas to meet technology development milestones of NASA s exploration-dedicated activities. Materials research tasks were targeted in five areas: (1) Thermal management materials, (2) propulsion materials, (3) materials characterization, (4) vehicle health monitoring materials, and (5) structural materials. Selected tasks were scheduled for completion such that these new materials could be incorporated into customer development plans.

Armor systems including coated core materials

DOEpatents

Chu, Henry S [Idaho Falls, ID; Lillo, Thomas M [Idaho Falls, ID; McHugh, Kevin M [Idaho Falls, ID

2012-07-31

An armor system and method involves providing a core material and a stream of atomized coating material that comprises a liquid fraction and a solid fraction. An initial layer is deposited on the core material by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is less than the liquid fraction of the stream of atomized coating material on a weight basis. An outer layer is then deposited on the initial layer by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is greater than the liquid fraction of the stream of atomized coating material on a weight basis.

Armor systems including coated core materials

DOEpatents

Chu, Henry S; Lillo, Thomas M; McHugh, Kevin M

2013-10-08

An armor system and method involves providing a core material and a stream of atomized coating material that comprises a liquid fraction and a solid fraction. An initial layer is deposited on the core material by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is less than the liquid fraction of the stream of atomized coating material on a weight basis. An outer layer is then deposited on the initial layer by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is greater than the liquid fraction of the stream of atomized coating material on a weight basis.

Catalyst material and method of making

DOEpatents

Matson, Dean W.; Fulton, John L.; Linehan, John C.; Bean, Roger M.; Brewer, Thomas D.; Werpy, Todd A.; Darab, John G.

1997-01-01

The material of the present invention is a mixture of catalytically active material and carrier materials, which may be catalytically active themselves. Hence, the material of the present invention provides a catalyst particle that has catalytically active material throughout its bulk volume as well as on its surface. The presence of the catalytically active material throughout the bulk volume is achieved by chemical combination of catalytically active materials with carrier materials prior to or simultaneously with crystallite formation.

Catalyst material and method of making

DOEpatents

Matson, D.W.; Fulton, J.L.; Linehan, J.C.; Bean, R.M.; Brewer, T.D.; Werpy, T.A.; Darab, J.G.

1997-07-29

The material of the present invention is a mixture of catalytically active material and carrier materials, which may be catalytically active themselves. Hence, the material of the present invention provides a catalyst particle that has catalytically active material throughout its bulk volume as well as on its surface. The presence of the catalytically active material throughout the bulk volume is achieved by chemical combination of catalytically active materials with carrier materials prior to or simultaneously with crystallite formation. 7 figs.

Material efficiency in a multi-material world.

PubMed

Lifset, Reid; Eckelman, Matthew

2013-03-13

Material efficiency--using less of a material to make a product or supply a service--is gaining attention as a means for accomplishing important environmental goals. The ultimate goal of material efficiency is not to use less physical material but to reduce the impacts associated with its use. This article examines the concept and definition of material efficiency and argues that for it to be an effective strategy it must confront the challenges of operating in a multi-material world, providing guidance when materials are used together and when they compete. A series of conceptions of material efficiency are described, starting with mass-based formulations and expanding to consider multiple resources in the supply chain of a single material, and then to multiple resources in the supply chains of multiple materials used together, and further to multiple environmental impacts. The conception of material efficiency is further broadened by considering material choice, exploring the technical and economic effects both of using less material and of materials competition. Finally, this entire materials-based techno-economic system is considered with respect to the impact of complex policies and political forces. The overall goal here is to show how the concept of material efficiency when faced with more expansive--and yet directly relevant--definitional boundaries is forced to confront analytical challenges that are both familiar and difficult in life cycle assessment and product-based approaches.

Diagnostic system for profiling micro-beams

DOEpatents

Elmer, John W.; Palmer, Todd A.; Teruya, Alan T.; Walton, Chris C.

2007-10-30

An apparatus for characterization of a micro beam comprising a micro modified Faraday cup assembly including a first layer of material, a second layer of material operatively connected to the first layer of material, a third layer of material operatively connected to the second layer of material, and a fourth layer of material operatively connected to the third layer of material. The first layer of material comprises an electrical conducting material and has at least one first layer radial slit extending through the first layer. An electrical ground is connected to the first layer. The second layer of material comprises an insulating material and has at least one second layer radial slit corresponding to the first layer radial slit in the first layer of material. The second layer radial slit extends through the second layer. The third layer of material comprises a conducting material and has at least one third layer radial slit corresponding to the second layer radial slit in the second layer of material. The third layer radial slit extends through the third layer. The fourth layer of material comprises an electrical conducting material but does not have slits. An electrical measuring device is connected to the fourth layer. The micro modified Faraday cup assembly is positioned to be swept by the micro beam.

Lightweight Combat Vehicle S and T Campaign

DTIC Science & Technology

2014-10-06

research in nano-materials, self - healing /diagnosing materials, multi-functional materials, and environmentally acceptable materials. The application...research includes nano-materials, self - healing /diagnosing materials, multi-functional materials, and environmentally acceptable materials.5 The 2003...hubs must be led by a not-for-profit organization, provide 50% cost share match, and are expected to become self -sufficient in 5 years. So far, all

NASA LaRC Hazardous Material Pharmacy

NASA Technical Reports Server (NTRS)

Esquenet, Remy

1995-01-01

In 1993-1994 the Office of Environmental Engineering contracted SAIC to develop NASA Langley's Pollution Prevention (P2) Program. One of the priority projects identified in this contract was the development of a hazardous waste minimization (HAZMIN)/hazardous materials reutilization (HAZMART) program in the form of a Hazardous Materials Pharmacy. A hazardous materials pharmacy is designed to reduce hazardous material procurement costs and hazardous waste disposal costs. This is accomplished through the collection and reissue of excess hazardous material. Currently, a rarely used hazardous material may be stored in a shop area, unused, until it passes its expiration date. The material is then usually disposed of as a hazardous waste, often at a greater expense than the original cost of the material. While this material was on the shelf expiring, other shop areas may have ordered new supplies of the same material. The hazardous material pharmacy would act as a clearinghouse for such materials. Material that is not going to be used would be turned in to the pharmacy. Other users could then be issued this material free of charge, thereby reducing procurement costs. The use of this material by another shop prevents it from expiring, thereby reducing hazardous waste disposal costs.

49 CFR 178.345-2 - Material and material thickness.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Material and material thickness. 178.345-2 Section... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.345-2 Material and material...

48 CFR 52.211-5 - Material Requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 48 Federal Acquisition Regulations System 2 2012-10-01 2012-10-01 false Material Requirements. 52....211-5 Material Requirements. As prescribed in 11.304, insert the following clause: Material... components, whether manufactured from virgin material, recovered material in the form of raw material, or...

48 CFR 52.211-5 - Material Requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 48 Federal Acquisition Regulations System 2 2014-10-01 2014-10-01 false Material Requirements. 52....211-5 Material Requirements. As prescribed in 11.304, insert the following clause: Material... components, whether manufactured from virgin material, recovered material in the form of raw material, or...

49 CFR 178.345-2 - Material and material thickness.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Material and material thickness. 178.345-2 Section... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.345-2 Material and material...

49 CFR 178.345-2 - Material and material thickness.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Material and material thickness. 178.345-2 Section... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.345-2 Material and material...

49 CFR 178.345-2 - Material and material thickness.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Material and material thickness. 178.345-2 Section... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.345-2 Material and material...

Combinatorial synthesis and screening of non-biological polymers

DOEpatents

Schultz, Peter G.; Xiang, Xiao-Dong; Goldwasser, Isy; Briceno, Gabriel; Sun, Xiao-Dong; Wang, Kai-An

2006-04-25

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Giant magnetoresistive cobalt oxide compounds

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

1998-01-01

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Giant magnetoresistive cobalt oxide compounds

DOEpatents

Schultz, P.G.; Xiang, X.; Goldwasser, I.

1998-07-07

Methods and apparatus are disclosed for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties. 58 figs.

Synthesis and screening combinatorial arrays of zeolites

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

2003-11-18

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial and high-throughput screening of materials libraries: review of state of the art.

PubMed

Potyrailo, Radislav; Rajan, Krishna; Stoewe, Klaus; Takeuchi, Ichiro; Chisholm, Bret; Lam, Hubert

2011-11-14

Rational materials design based on prior knowledge is attractive because it promises to avoid time-consuming synthesis and testing of numerous materials candidates. However with the increase of complexity of materials, the scientific ability for the rational materials design becomes progressively limited. As a result of this complexity, combinatorial and high-throughput (CHT) experimentation in materials science has been recognized as a new scientific approach to generate new knowledge. This review demonstrates the broad applicability of CHT experimentation technologies in discovery and optimization of new materials. We discuss general principles of CHT materials screening, followed by the detailed discussion of high-throughput materials characterization approaches, advances in data analysis/mining, and new materials developments facilitated by CHT experimentation. We critically analyze results of materials development in the areas most impacted by the CHT approaches, such as catalysis, electronic and functional materials, polymer-based industrial coatings, sensing materials, and biomaterials.

Systems and methods for treating material

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

Scheele, Randall D; McNamara, Bruce K

Systems for treating material are provided that can include a vessel defining a volume, at least one conduit coupled to the vessel and in fluid communication with the vessel, material within the vessel, and NF.sub.3 material within the conduit. Methods for fluorinating material are provided that can include exposing the material to NF.sub.3 to fluorinate at least a portion of the material. Methods for separating components of material are also provided that can include exposing the material to NF.sub.3 to at least partially fluorinate a portion of the material, and separating at least one fluorinated component of the fluorinated portionmore » from the material. The materials exposed to the NF.sub.3 material can include but are not limited to one or more of U, Ru, Rh, Mo, Tc, Np, Pu, Sb, Ag, Am, Sn, Zr, Cs, Th, and/or Rb.« less

Methods of using structures including catalytic materials disposed within porous zeolite materials to synthesize hydrocarbons

DOEpatents

Rollins, Harry W [Idaho Falls, ID; Petkovic, Lucia M [Idaho Falls, ID; Ginosar, Daniel M [Idaho Falls, ID

2011-02-01

Catalytic structures include a catalytic material disposed within a zeolite material. The catalytic material may be capable of catalyzing a formation of methanol from carbon monoxide and/or carbon dioxide, and the zeolite material may be capable of catalyzing a formation of hydrocarbon molecules from methanol. The catalytic material may include copper and zinc oxide. The zeolite material may include a first plurality of pores substantially defined by a crystal structure of the zeolite material and a second plurality of pores dispersed throughout the zeolite material. Systems for synthesizing hydrocarbon molecules also include catalytic structures. Methods for synthesizing hydrocarbon molecules include contacting hydrogen and at least one of carbon monoxide and carbon dioxide with such catalytic structures. Catalytic structures are fabricated by forming a zeolite material at least partially around a template structure, removing the template structure, and introducing a catalytic material into the zeolite material.

Stratigraphy of the Perrine and Nun Sulci quadrangles (Jg-2 and Jg-5), Ganymede

NASA Technical Reports Server (NTRS)

Mcgill, George E.; Squyres, Steven W.

1991-01-01

Dark and light terrain materials in the Perrine and Nun Sulci quadrangles are divided into nine map units, four dark, and five light. These are placed in time-stratigraphic sequence primarily by means of embayment and cross-cutting relationships. Dark terrain is generally more heavily cratered and thus older that light terrain but, at least in these quadrangles, crater densities are not reliable indicators of relative ages among the four dark material units. The four mapped material units within dark terrain are: cratered dark materials (dc), grooved dark materials (dg), transitional dark materials (di), and dark materials, undivided (d). The five mapped units within light terrain are: intermediate light materials (li), grooved light materials (lg), irregularly grooved light materials (lgl), smooth light materials (ls), and light materials, undivided.

Polymeric membrane materials for artificial organs.

PubMed

Kawakami, Hiroyoshi

2008-01-01

Many polymeric materials have already been used in the field of artificial organs. However, the materials used in artificial organs are not necessarily created with the best material selectivity and materials design; therefore, the development of synthesized polymeric membrane materials for artificial organs based on well-defined designs is required. The approaches to the development of biocompatible polymeric materials fall into three categories: (1) control of physicochemical characteristics on material surfaces, (2) modification of material surfaces using biomolecules, and (3) construction of biomimetic membrane surfaces. This review will describe current issues regarding polymeric membrane materials for use in artificial organs.

Approximate static condensation algorithm for solving multi-material diffusion problems on meshes non-aligned with material interfaces

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

Kikinzon, Evgeny; Kuznetsov, Yuri; Lipnikov, Konstatin

In this study, we describe a new algorithm for solving multi-material diffusion problem when material interfaces are not aligned with the mesh. In this case interface reconstruction methods are used to construct approximate representation of interfaces between materials. They produce so-called multi-material cells, in which materials are represented by material polygons that contain only one material. The reconstructed interface is not continuous between cells. Finally, we suggest the new method for solving multi-material diffusion problems on such meshes and compare its performance with known homogenization methods.

Approximate static condensation algorithm for solving multi-material diffusion problems on meshes non-aligned with material interfaces

DOE PAGES

Kikinzon, Evgeny; Kuznetsov, Yuri; Lipnikov, Konstatin; ...

2017-07-08

In this study, we describe a new algorithm for solving multi-material diffusion problem when material interfaces are not aligned with the mesh. In this case interface reconstruction methods are used to construct approximate representation of interfaces between materials. They produce so-called multi-material cells, in which materials are represented by material polygons that contain only one material. The reconstructed interface is not continuous between cells. Finally, we suggest the new method for solving multi-material diffusion problems on such meshes and compare its performance with known homogenization methods.

Space Exploration: Oh, the Materials You'll Need!

NASA Technical Reports Server (NTRS)

Johnson, Sylvia M.

2016-01-01

Space exploration has many challenges and materials are critical for many of the systems required to enable robotic or human space exploration. This talk will highlight challenges for materials with an emphasis on thermal protection materials and systems. Solving the materials issues will require thinking about materials in the systems and environments where are they to be used. In many cases the materials must be designed for the application, and the system needs to be designed with the materials in mind. The talk will conclude with some thoughts on the skills needed for materials scientists and engineers working on materials for space.

10 CFR 962.3 - Byproduct material.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 4 2010-01-01 2010-01-01 false Byproduct material. 962.3 Section 962.3 Energy DEPARTMENT OF ENERGY BYPRODUCT MATERIAL § 962.3 Byproduct material. (a) For purposes of this part, the term byproduct material means any radioactive material (except special nuclear material) yielded in or made...

10 CFR 962.3 - Byproduct material.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 4 2011-01-01 2011-01-01 false Byproduct material. 962.3 Section 962.3 Energy DEPARTMENT OF ENERGY BYPRODUCT MATERIAL § 962.3 Byproduct material. (a) For purposes of this part, the term byproduct material means any radioactive material (except special nuclear material) yielded in or made...

Method of making nanostructured glass-ceramic waste forms

DOEpatents

Gao, Huizhen; Wang, Yifeng; Rodriguez, Mark A.; Bencoe, Denise N.

2012-12-18

A method of rendering hazardous materials less dangerous comprising trapping the hazardous material in nanopores of a nanoporous composite material, reacting the trapped hazardous material to render it less volatile/soluble, sealing the trapped hazardous material, and vitrifying the nanoporous material containing the less volatile/soluble hazardous material.

10 CFR 962.3 - Byproduct material.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 4 2013-01-01 2013-01-01 false Byproduct material. 962.3 Section 962.3 Energy DEPARTMENT OF ENERGY BYPRODUCT MATERIAL § 962.3 Byproduct material. (a) For purposes of this part, the term byproduct material means any radioactive material (except special nuclear material) yielded in or made...

10 CFR 962.3 - Byproduct material.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 4 2012-01-01 2012-01-01 false Byproduct material. 962.3 Section 962.3 Energy DEPARTMENT OF ENERGY BYPRODUCT MATERIAL § 962.3 Byproduct material. (a) For purposes of this part, the term byproduct material means any radioactive material (except special nuclear material) yielded in or made...

29 CFR 1910.1096 - Ionizing radiation.

Code of Federal Regulations, 2012 CFR

2012-07-01

... material, as defined in the Atomic Energy Act of 1954, as amended, under a license issued by the Nuclear... material, byproduct material, or special nuclear material, as defined in the Atomic Energy Act of 1954, as... source material, byproduct material, or special nuclear material, as defined in the Atomic Energy Act of...

29 CFR 1910.1096 - Ionizing radiation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... material, as defined in the Atomic Energy Act of 1954, as amended, under a license issued by the Nuclear... material, byproduct material, or special nuclear material, as defined in the Atomic Energy Act of 1954, as... source material, byproduct material, or special nuclear material, as defined in the Atomic Energy Act of...

29 CFR 1910.1096 - Ionizing radiation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... material, as defined in the Atomic Energy Act of 1954, as amended, under a license issued by the Nuclear... material, byproduct material, or special nuclear material, as defined in the Atomic Energy Act of 1954, as... source material, byproduct material, or special nuclear material, as defined in the Atomic Energy Act of...

The Physics and Chemistry of Materials

NASA Astrophysics Data System (ADS)

Gersten, Joel I.; Smith, Frederick W.

2001-06-01

A comprehensive introduction to the structure, properties, and applications of materials This title provides the first unified treatment for the broad subject of materials. Authors Gersten and Smith use a fundamental approach to define the structure and properties of a wide range of solids on the basis of the local chemical bonding and atomic order present in the material. Emphasizing the physical and chemical origins of material properties, the book focuses on the most technologically important materials being utilized and developed by scientists and engineers. Appropriate for use in advanced materials courses, The Physics and Chemistry of Materials provides the background information necessary to assimilate the current academic and patent literature on materials and their applications. Problem sets, illustrations, and helpful tables complete this well-rounded new treatment. Five sections cover these important topics: * Structure of materials, including crystal structure, bonding in solids, diffraction and the reciprocal lattice, and order and disorder in solids * Physical properties of materials, including electrical, thermal, optical, magnetic, and mechanical properties * Classes of materials, including semiconductors, superconductors, magnetic materials, and optical materials in addition to metals, ceramics, polymers, dielectrics, and ferroelectrics * A section on surfaces, thin films, interfaces, and multilayers discusses the effects of spatial discontinuities in the physical and chemical structure of materials * A section on synthesis and processing examines the effects of synthesis on the structure and properties of various materials This book is enhanced by a Web-based supplement that offers advanced material together with an entire electronic chapter on the characterization of materials. The Physics and Chemistry of Materials is a complete introduction to the structure and properties of materials for students and an excellent reference for scientists and engineers.

Developing Novel Protein-based Materials using Ultrabithorax: Production, Characterization, and Functionalization

NASA Astrophysics Data System (ADS)

Huang, Zhao

2011-12-01

Compared to 'conventional' materials made from metal, glass, or ceramics, protein-based materials have unique mechanical properties. Furthermore, the morphology, mechanical properties, and functionality of protein-based materials may be optimized via sequence engineering for use in a variety of applications, including textile materials, biosensors, and tissue engineering scaffolds. The development of recombinant DNA technology has enabled the production and engineering of protein-based materials ex vivo. However, harsh production conditions can compromise the mechanical properties of protein-based materials and diminish their ability to incorporate functional proteins. Developing a new generation of protein-based materials is crucial to (i) improve materials assembly conditions, (ii) create novel mechanical properties, and (iii) expand the capacity to carry functional protein/peptide sequences. This thesis describes development of novel protein-based materials using Ultrabithorax, a member of the Hox family of proteins that regulate developmental pathways in Drosophila melanogaster. The experiments presented (i) establish the conditions required for the assembly of Ubx-based materials, (ii) generate a wide range of Ubx morphologies, (iii) examine the mechanical properties of Ubx fibers, (iv) incorporate protein functions to Ubx-based materials via gene fusion, (v) pattern protein functions within the Ubx materials, and (vi) examine the biocompatibility of Ubx materials in vitro. Ubx-based materials assemble at mild conditions compatible with protein folding and activity, which enables Ubx chimeric materials to retain the function of appended proteins in spatial patterns determined by materials assembly. Ubx-based materials also display mechanical properties comparable to existing protein-based materials and demonstrate good biocompatibility with living cells in vitro. Taken together, this research demonstrates the unique features and future potential of novel Ubx-based materials.

Non-thermal plasma conversion of hydrocarbons

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

Strohm, James J.; Skoptsov, George L.; Musselman, Evan T.

A non-thermal plasma is generated to selectively convert a precursor to a product. More specifically, plasma forming material and a precursor material are provided to a reaction zone of a vessel. The reaction zone is exposed to microwave radiation, including exposing the plasma forming material and the precursor material to the microwave radiation. The exposure of the plasma forming material to the microwave radiation selectively converts the plasma forming material to a non-thermal plasma including formation of one or more streamers. The precursor material is mixed with the plasma forming material and the precursor material is exposed to the non-thermalmore » plasma including exposing the precursor material to the one or more streamers. The exposure of the precursor material to the streamers and the microwave radiation selectively converts the precursor material to a product.« less

Hydrogen gettering packing material, and process for making same

DOEpatents

LeMay, James D.; Thompson, Lisa M.; Smith, Henry Michael; Schicker, James R.

2001-01-01

A hydrogen gettering system for a sealed container is disclosed comprising packing material for use within the sealed container, and a coating film containing hydrogen gettering material on at least a portion of the surface of such packing material. The coating film containing the hydrogen gettering material comprises a mixture of one or more organic materials capable of reacting with hydrogen and one or more catalysts capable of catalyzing the reaction of hydrogen with such one or more organic materials. The mixture of one or more organic materials capable of reacting with hydrogen and the one or more catalysts is dispersed in a suitable carrier which preferably is a curable film-forming material. In a preferred embodiment, the packing material comprises a foam material which is compatible with the coating film containing hydrogen gettering material thereon.

Buffer layers for coated conductors

DOEpatents

Stan, Liliana [Los Alamos, NM; Jia, Quanxi [Los Alamos, NM; Foltyn, Stephen R [Los Alamos, NM

2011-08-23

A composite structure is provided including a base substrate, an IBAD oriented material upon the base substrate, and a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates upon the IBAD oriented material. Additionally, an article is provided including a base substrate, an IBAD oriented material upon the base substrate, a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates upon the IBAD oriented material, and a thick film upon the cubic metal oxide material. Finally, a superconducting article is provided including a base substrate, an IBAD oriented material upon the base substrate, a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates upon the IBAD oriented material, and an yttrium barium copper oxide material upon the cubic metal oxide material.

Composite materials formed with anchored nanostructures

DOEpatents

Seals, Roland D; Menchhofer, Paul A; Howe, Jane Y; Wang, Wei

2015-03-10

A method of forming nano-structure composite materials that have a binder material and a nanostructure fiber material is described. A precursor material may be formed using a mixture of at least one metal powder and anchored nanostructure materials. The metal powder mixture may be (a) Ni powder and (b) NiAl powder. The anchored nanostructure materials may comprise (i) NiAl powder as a support material and (ii) carbon nanotubes attached to nanoparticles adjacent to a surface of the support material. The process of forming nano-structure composite materials typically involves sintering the mixture under vacuum in a die. When Ni and NiAl are used in the metal powder mixture Ni.sub.3Al may form as the binder material after sintering. The mixture is sintered until it consolidates to form the nano-structure composite material.

Green materials for sustainable development

NASA Astrophysics Data System (ADS)

Purwasasmita, B. S.

2017-03-01

Sustainable development is an integrity of multidiscipline concept combining ecological, social and economic aspects to construct a liveable human living system. The sustainable development can be support through the development of green materials. Green materials offers a unique characteristic and properties including abundant in nature, less toxic, economically affordable and versatility in term of physical and chemical properties. Green materials can be applied for a numerous field in science and technology applications including for energy, building, construction and infrastructures, materials science and engineering applications and pollution management and technology. For instance, green materials can be developed as a source for energy production. Green materials including biomass-based source can be developed as a source for biodiesel and bioethanol production. Biomass-based materials also can be transformed into advanced functionalized materials for advanced bio-applications such as the transformation of chitin into chitosan which further used for biomedicine, biomaterials and tissue engineering applications. Recently, cellulose-based material and lignocellulose-based materials as a source for the developing functional materials attracted the potential prospect for biomaterials, reinforcing materials and nanotechnology. Furthermore, the development of pigment materials has gaining interest by using the green materials as a source due to their unique properties. Eventually, Indonesia as a large country with a large biodiversity can enhance the development of green material to strengthen our nation competitiveness and develop the materials technology for the future.

Coated armor system and process for making the same

DOEpatents

Chu, Henry S.; Lillo, Thomas M.; McHugh, Kevin M.

2010-11-23

An armor system and method involves providing a core material and a stream of atomized coating material that comprises a liquid fraction and a solid fraction. An initial layer is deposited on the core material by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is less than the liquid fraction of the stream of atomized coating material on a weight basis. An outer layer is then deposited on the initial layer by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is greater than the liquid fraction of the stream of atomized coating material on a weight basis.

Systems and methods for forming defects on graphitic materials and curing radiation-damaged graphitic materials

DOEpatents

Ryu, Sunmin; Brus, Louis E.; Steigerwald, Michael L.; Liu, Haitao

2012-09-25

Systems and methods are disclosed herein for forming defects on graphitic materials. The methods for forming defects include applying a radiation reactive material on a graphitic material, irradiating the applied radiation reactive material to produce a reactive species, and permitting the reactive species to react with the graphitic material to form defects. Additionally, disclosed are methods for removing defects on graphitic materials.

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

Mccall, Scott K.; Kuntz, Joshua D.

A method of making a bulk exchange spring magnet by providing a magnetically soft material, providing a hard magnetic material, and producing a composite of said magnetically soft material and said hard magnetic material to make the bulk exchange spring magnet. The step of producing a composite of magnetically soft material and hard magnetic material is accomplished by electrophoretic deposition of the magnetically soft material and the hard magnetic material to make the bulk exchange spring magnet.

Municipal waste processing apparatus

DOEpatents

Mayberry, John L.

1988-01-01

Municipal waste materials are processed by crushing the materials so that pieces of noncombustible material are smaller than a selected size and pieces of combustible material are larger than the selected size. The crushed materials are placed on a vibrating mesh screen conveyor belt having openings which pass the smaller, noncombustible pieces of material, but do not pass the larger, combustible pieces of material. Pieces of material which become lodged in the openings of the conveyor belt may be removed by cylindrical deraggers or pressurized air. The crushed materials may be fed onto the conveyor belt by a vibrating feed plate which shakes the materials so that they tend to lie flat.

Dopant type and/or concentration selective dry photochemical etching of semiconductor materials

DOEpatents

Ashby, Carol I. H.; Dishman, James L.

1987-01-01

A method of selectively photochemically dry etching a first semiconductor material of a given composition in the presence of a second semiconductor material which is of a composition different from said first material, said second material substantially not being etched during said method, comprises subjecting both materials to the same photon flux of an energy greater than their respective direct bandgaps and to the same gaseous chemical etchant under conditions where said etchant would be ineffective for chemical etching of either material were the photons not present, said conditions also being such that the resultant electronic structure of the first semiconductor material under said photon flux is sufficient for the first material to undergo substantial photochemical etching under said conditions and being such that the resultant electronic structure of the second semiconductor material under said photon flux is not sufficient for the second material to undergo substantial photochemical etching under said conditions. In a preferred mode, the materials are subjected to a bias voltage which suppresses etching in n- or p- type material but not in p- or n-type material, respectively; or suppresses etching in the more heavily doped of two n-type or two p-type materials.

Dopant type and/or concentration selective dry photochemical etching of semiconductor materials

DOEpatents

Ashby, C.R.H.; Dishman, J.L.

1985-10-11

Disclosed is a method of selectively photochemically dry etching a first semiconductor material of a given composition in the presence of a second semiconductor material which is of a composition different from said first material, said second material substantially not being etched during said method. The method comprises subjecting both materials to the same photon flux of an energy greater than their respective direct bandgaps and to the same gaseous chemical etchant under conditions where said etchant would be ineffective for chemical etching of either material were the photons not present, said conditions also being such that the resultant electronic structure of the first semiconductor material under said photon flux is sufficient for the first material to undergo substantial photochemical etching under said conditions and being such that the resultant electronic structure of the second semiconductor material under said photon flux is not sufficient for the second material to undergo substantial photochemical etching under said conditions. In a preferred mode, the materials are subjected to a bias voltage which suppresses etching in n- or p-type material but not in p- or n-type material, respectively; or suppresses etching in the more heavily doped of two n-type or two p-type materials.

Critical Materials Institute

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

King, Alex

2013-01-09

Ames Laboratory Director Alex King talks about the goals of the Critical Materials Institute in diversifying the supply of critical materials, developing substitute materials, developing tools and techniques for recycling critical materials, and forecasting materials needs to avoid future shortages.

Critical Materials Institute

ScienceCinema

King, Alex

2017-12-22

Ames Laboratory Director Alex King talks about the goals of the Critical Materials Institute in diversifying the supply of critical materials, developing substitute materials, developing tools and techniques for recycling critical materials, and forecasting materials needs to avoid future shortages.

Composite material dosimeters

DOEpatents

Miller, Steven D.

1996-01-01

The present invention is a composite material containing a mix of dosimeter material powder and a polymer powder wherein the polymer is transparent to the photon emission of the dosimeter material powder. By mixing dosimeter material powder with polymer powder, less dosimeter material is needed compared to a monolithic dosimeter material chip. Interrogation is done with excitation by visible light.

Computational Text Analysis: A More Comprehensive Approach to Determine Readability of Reading Materials

ERIC Educational Resources Information Center

Aziz, Anealka; Fook, Chan Yuen; Alsree, Zubaida

2010-01-01

Reading materials are considered having high readability if readers are interested to read the materials, understand the content of the materials and able to read the materials fluently. In contrast, reading materials with low readability discourage readers from reading the materials, create difficulties for readers to understand the content of…

10 CFR 74.41 - Nuclear material control and accounting for special nuclear material of moderate strategic...

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 2 2011-01-01 2011-01-01 false Nuclear material control and accounting for special nuclear material of moderate strategic significance. 74.41 Section 74.41 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Special Nuclear Material...

10 CFR 74.31 - Nuclear material control and accounting for special nuclear material of low strategic significance.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 2 2014-01-01 2014-01-01 false Nuclear material control and accounting for special nuclear material of low strategic significance. 74.31 Section 74.31 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Special Nuclear Material of Low...

10 CFR 74.41 - Nuclear material control and accounting for special nuclear material of moderate strategic...

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 2 2013-01-01 2013-01-01 false Nuclear material control and accounting for special nuclear material of moderate strategic significance. 74.41 Section 74.41 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Special Nuclear Material...

10 CFR 74.41 - Nuclear material control and accounting for special nuclear material of moderate strategic...

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 2 2014-01-01 2014-01-01 false Nuclear material control and accounting for special nuclear material of moderate strategic significance. 74.41 Section 74.41 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Special Nuclear Material...

10 CFR 74.41 - Nuclear material control and accounting for special nuclear material of moderate strategic...

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 2 2012-01-01 2012-01-01 false Nuclear material control and accounting for special nuclear material of moderate strategic significance. 74.41 Section 74.41 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Special Nuclear Material...

10 CFR 74.31 - Nuclear material control and accounting for special nuclear material of low strategic significance.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 2 2012-01-01 2012-01-01 false Nuclear material control and accounting for special nuclear material of low strategic significance. 74.31 Section 74.31 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Special Nuclear Material of Low...

10 CFR 74.41 - Nuclear material control and accounting for special nuclear material of moderate strategic...

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Nuclear material control and accounting for special nuclear material of moderate strategic significance. 74.41 Section 74.41 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Special Nuclear Material...

10 CFR 74.31 - Nuclear material control and accounting for special nuclear material of low strategic significance.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 2 2011-01-01 2011-01-01 false Nuclear material control and accounting for special nuclear material of low strategic significance. 74.31 Section 74.31 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Special Nuclear Material of Low...

10 CFR 74.31 - Nuclear material control and accounting for special nuclear material of low strategic significance.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 2 2013-01-01 2013-01-01 false Nuclear material control and accounting for special nuclear material of low strategic significance. 74.31 Section 74.31 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Special Nuclear Material of Low...

Theoretical backgrounds of non-tempered materials production based on new raw materials

NASA Astrophysics Data System (ADS)

Lesovik, V. S.; Volodchenko, A. A.; Glagolev, E. S.; Chernysheva, N. V.; Lashina, I. V.; Feduk, R. S.

2018-03-01

One of the trends in construction material science is development and implementation of highly effective finish materials which improve architectural exterior of cities. Silicate materials widely-used in the construction today have rather low decorative properties. Different coloring agents are used in order to produce competitive materials, but due to the peculiarities of the production, process very strict specifications are applied to them. The use of industrial wastes or variety of rock materials as coloring agents is of great interest nowadays. The article shows that clay rock can be used as raw material in production of finish materials of non-autoclaved solidification. This raw material due to its material composition actively interacts with cementing component in steam treatment at 90–95 °C with formation of cementing joints that form a firm coagulative-cristalized and crystallization structure of material providing high physic-mechanical properties of silicate goods. It is determined that energy-saving, colored finish materials with compression strength up to 16 MPa can be produced from clay rocks.

Materials science and architecture

NASA Astrophysics Data System (ADS)

Bechthold, Martin; Weaver, James C.

2017-12-01

Materiality — the use of various materials in architecture — has been fundamental to the design and construction of buildings, and materials science has traditionally responded to needs formulated by design, engineering and construction professionals. Material properties and processes are shaping buildings and influencing how they perform. The advent of technologies such as digital fabrication, robotics and 3D printing have not only accelerated the development of new construction solutions, but have also led to a renewed interest in materials as a catalyst for novel architectural design. In parallel, materials science has transformed from a field that explains materials to one that designs materials from the bottom up. The conflation of these two trends is giving rise to materials-based design research in which architects, engineers and materials scientists work as partners in the conception of new materials systems and their applications. This Review surveys this development for different material classes (wood, ceramics, metals, concrete, glass, synthetic composites and polymers), with an emphasis on recent trends and innovations.

Organic hybrid planar-nanocrystalline bulk heterojunctions

DOEpatents

Forrest, Stephen R [Ann Arbor, MI; Yang, Fan [Piscataway, NJ

2011-03-01

A photosensitive optoelectronic device having an improved hybrid planar bulk heterojunction includes a plurality of photoconductive materials disposed between the anode and the cathode. The photoconductive materials include a first continuous layer of donor material and a second continuous layer of acceptor material. A first network of donor material or materials extends from the first continuous layer toward the second continuous layer, providing continuous pathways for conduction of holes to the first continuous layer. A second network of acceptor material or materials extends from the second continuous layer toward the first continuous layer, providing continuous pathways for conduction of electrons to the second continuous layer. The first network and the second network are interlaced with each other. At least one other photoconductive material is interspersed between the interlaced networks. This other photoconductive material or materials has an absorption spectra different from the donor and acceptor materials.

Organic hybrid planar-nanocrystalline bulk heterojunctions

DOEpatents

Forrest, Stephen R.; Yang, Fan

2013-04-09

A photosensitive optoelectronic device having an improved hybrid planar bulk heterojunction includes a plurality of photoconductive materials disposed between the anode and the cathode. The photoconductive materials include a first continuous layer of donor material and a second continuous layer of acceptor material. A first network of donor material or materials extends from the first continuous layer toward the second continuous layer, providing continuous pathways for conduction of holes to the first continuous layer. A second network of acceptor material or materials extends from the second continuous layer toward the first continuous layer, providing continuous pathways for conduction of electrons to the second continuous layer. The first network and the second network are interlaced with each other. At least one other photoconductive material is interspersed between the interlaced networks. This other photoconductive material or materials has an absorption spectra different from the donor and acceptor materials.

Process for producing dispersed particulate composite materials

DOEpatents

Henager, Jr., Charles H.; Hirth, John P.

1995-01-01

This invention is directed to a process for forming noninterwoven dispersed particulate composite products. In one case a composite multi-layer film product comprises a substantially noninterwoven multi-layer film having a plurality of discrete layers. This noninterwoven film comprises at least one discrete layer of a first material and at least one discrete layer of a second material. In another case the first and second materials are blended together with each other. In either case, the first material comprises a metalloid and the second material a metal compound. At least one component of a first material in one discrete layer undergoes a solid state displacement reaction with at least one component of a second material thereby producing the requisite noninterwoven composite film product. Preferably, the first material comprises silicon, the second material comprises Mo.sub.2 C, the third material comprises SiC and the fourth material comprises MoSi.sub.2.

Systems including catalysts in porous zeolite materials within a reactor for use in synthesizing hydrocarbons

DOEpatents

Rolllins, Harry W [Idaho Falls, ID; Petkovic, Lucia M [Idaho Falls, ID; Ginosar, Daniel M [Idaho Falls, ID

2012-07-24

Catalytic structures include a catalytic material disposed within a zeolite material. The catalytic material may be capable of catalyzing a formation of methanol from carbon monoxide and/or carbon dioxide, and the zeolite material may be capable of catalyzing a formation of hydrocarbon molecules from methanol. The catalytic material may include copper and zinc oxide. The zeolite material may include a first plurality of pores substantially defined by a crystal structure of the zeolite material and a second plurality of pores dispersed throughout the zeolite material. Systems for synthesizing hydrocarbon molecules also include catalytic structures. Methods for synthesizing hydrocarbon molecules include contacting hydrogen and at least one of carbon monoxide and carbon dioxide with such catalytic structures. Catalytic structures are fabricated by forming a zeolite material at least partially around a template structure, removing the template structure, and introducing a catalytic material into the zeolite material.

All 2D, high mobility, flexible, transparent thin film transistor

DOEpatents

Das, Saptarshi; Sumant, Anirudha V.; Roelofs, Andreas

2017-01-17

A two-dimensional thin film transistor and a method for manufacturing a two-dimensional thin film transistor includes layering a semiconducting channel material on a substrate, providing a first electrode material on top of the semiconducting channel material, patterning a source metal electrode and a drain metal electrode at opposite ends of the semiconducting channel material from the first electrode material, opening a window between the source metal electrode and the drain metal electrode, removing the first electrode material from the window located above the semiconducting channel material providing a gate dielectric above the semiconducting channel material, and providing a top gate above the gate dielectric, the top gate formed from a second electrode material. The semiconducting channel material is made of tungsten diselenide, the first electrode material and the second electrode material are made of graphene, and the gate dielectric is made of hexagonal boron nitride.

Development of aircraft brake materials. [evaluation of metal and ceramic materials in sliding tests simulation of aircraft braking

NASA Technical Reports Server (NTRS)

Ho, T. L.; Peterson, M. B.

1974-01-01

The requirements of brake materials were outlined and a survey made to select materials to meet the needs of high temperature brakes. A number of metals and ceramic materials were selected and evaluated in sliding tests which simulated aircraft braking. Nickel, molybdenum tungsten, Zr02, high temperature cements and carbons were tested. Additives were then incorporated into these materials to optimize their wear or strength behavior with particular emphasis on nickel and molybdenum base materials and a high temperature potassium silicate cement. Optimum materials were developed which improved wear behavior over conventional brake materials in the simulated test. The best materials are a nickel, aluminum oxide, lead tungstate composition containing graphite or molybdenum disulphite; a molybdenum base material containing LPA100 (an intermetallic compound of cobalt, molybdenum, and silicon); and a carbon material (P5).

Thermoelectric skutterudite compositions and methods for producing the same

DOEpatents

Ren, Zhifeng; Yang, Jian; Yan, Xiao; He, Qinyu; Chen, Gang; Hao, Qing

2014-11-11

Compositions related to skutterudite-based thermoelectric materials are disclosed. Such compositions can result in materials that have enhanced ZT values relative to one or more bulk materials from which the compositions are derived. Thermoelectric materials such as n-type and p-type skutterudites with high thermoelectric figures-of-merit can include materials with filler atoms and/or materials formed by compacting particles (e.g., nanoparticles) into a material with a plurality of grains each having a portion having a skutterudite-based structure. Methods of forming thermoelectric skutterudites, which can include the use of hot press processes to consolidate particles, are also disclosed. The particles to be consolidated can be derived from (e.g., grinded from), skutterudite-based bulk materials, elemental materials, other non-Skutterudite-based materials, or combinations of such materials.

Visible scintillation photodetector device incorporating chalcopyrite semiconductor crystals

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

Stowe, Ashley C.; Burger, Arnold

2017-04-04

A photodetector device, including: a scintillator material operable for receiving incident radiation and emitting photons in response; a photodetector material coupled to the scintillator material operable for receiving the photons emitted by the scintillator material and generating a current in response, wherein the photodetector material includes a chalcopyrite semiconductor crystal; and a circuit coupled to the photodetector material operable for characterizing the incident radiation based on the current generated by the photodetector material. Optionally, the scintillator material includes a gamma scintillator material and the incident radiation received includes gamma rays. Optionally, the photodetector material is further operable for receiving thermalmore » neutrons and generating a current in response. The circuit is further operable for characterizing the thermal neutrons based on the current generated by the photodetector material.« less

Methods of producing armor systems, and armor systems produced using such methods

DOEpatents

Chu, Henry S; Lillo, Thomas M; McHugh, Kevin M

2013-02-19

An armor system and method involves providing a core material and a stream of atomized coating material that comprises a liquid fraction and a solid fraction. An initial layer is deposited on the core material by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is less than the liquid fraction of the stream of atomized coating material on a weight basis. An outer layer is then deposited on the initial layer by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is greater than the liquid fraction of the stream of atomized coating material on a weight basis.

Thermoelectric Skutterudite Compositions and Methods for Producing the Same

NASA Technical Reports Server (NTRS)

Yang, Jian (Inventor); Yan, Xiao (Inventor); Ren, Zhifeng (Inventor); Hao, Qing (Inventor); He, Qinyu (Inventor); Chen, Gang (Inventor)

2014-01-01

Compositions related to skutterudite-based thermoelectric materials are disclosed. Such compositions can result in materials that have enhanced ZT values relative to one or more bulk materials from which the compositions are derived. Thermoelectric materials such as n-type and p-type skutterudites with high thermoelectric figures-of-merit can include materials with filler atoms and/or materials formed by compacting particles (e.g., nanoparticles) into a material with a plurality of grains each having a portion having a skutterudite-based structure. Methods of forming thermoelectric skutterudites, which can include the use of hot press processes to consolidate particles, are also disclosed. The particles to be consolidated can be derived from (e.g., grinded from), skutterudite-based bulk materials, elemental materials, other non-Skutterudite-based materials, or combinations of such materials.

Encapsulation of thermal energy storage media

DOEpatents

Dhau, Jaspreet; Goswami, Dharendra; Jotshi, Chand K.; Stefanakos, Elias K.

2017-09-19

In one embodiment, a phase change material is encapsulated by forming a phase change material pellet, coating the pellet with flexible material, heating the coated pellet to melt the phase change material, wherein the phase change materials expands and air within the pellet diffuses out through the flexible material, and cooling the coated pellet to solidify the phase change material.

75 FR 30863 - Nixon Presidential Historical Materials: Opening of Materials

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-02

... NATIONAL ARCHIVES AND RECORDS ADMINISTRATION Nixon Presidential Historical Materials: Opening of Materials AGENCY: National Archives and Records Administration. ACTION: Notice of opening of additional materials. SUMMARY: This notice announces the opening of additional Nixon Presidential Historical Materials...

Inert electrode connection

DOEpatents

Weyand, J.D.; Woods, R.W.; DeYoung, D.H.; Ray, S.P.

1985-02-19

An inert electrode connection is disclosed wherein a layer of inert electrode material is bonded to a layer of conductive material by providing at least one intermediate layer of material therebetween comprising a predetermined ratio of inert material to conductive material. In a preferred embodiment, the connection is formed by placing in a die a layer of powdered inert material, at least one layer of a mixture of powdered inert material and conductive material, and a layer of powdered conductive material. The connection is then formed by pressing the material at 15,000--20,000 psi to form a powder compact and then densifying the powder compact in an inert or reducing atmosphere at a temperature of 1,200--1,500 C. 5 figs.

Martian surface materials

NASA Technical Reports Server (NTRS)

Moore, H. J.

1991-01-01

A semiquantitative appreciation for the physical properties of the Mars surface materials and their global variations can be gained from the Viking Lander and remote sensing observations. Analyses of Lander data yields estimates of the mechanical properties of the soil-like surface materials and best guess estimates can be made for the remote sensing signatures of the soil-like materials at the landing sites. Results show that significant thickness of powderlike surface materials with physical properties similar to drift material are present on Mars and probably pervasive in the Tharsis region. It also appears likely that soil-like materials similar to crusty to cloddy material are typical for Mars, and that soil-like material similar to blocky material are common on Mars.

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

Seo, Dong-Kyun; Medpelli, Dinesh; Ladd, Danielle

A product formed from a first material including a geopolymer resin material, a geopolymer material, or a combination thereof by contacting the first material with a fluid and removing at least some of the fluid to yield a product. The first material may be formed by heating and/or aging an initial geopolymer resin material to yield the first material before contacting the first material with the fluid. In some cases, contacting the first material with the fluid breaks up or disintegrates the first material (e.g., in response to contact with the fluid and in the absence of external mechanical stress),more » thereby forming particles having an external dimension in a range between 1 nm and 2 cm.« less

Orbital foamed material extruder

NASA Technical Reports Server (NTRS)

Tucker, Dennis S. (Inventor)

2009-01-01

This invention is a process for producing foamed material in space comprising the steps of: rotating the material to simulate the force of gravity; heating the rotating material until it is molten; extruding the rotating, molten material; injecting gas into the extruded, rotating, molten material to produce molten foamed material; allowing the molten foamed material to cool to below melting temperature to produce the foamed material. The surface of the extruded foam may be heated to above melting temperature and allowed to cool to below melting temperature. The extruded foam may also be cut to predetermined length. The starting material may be metal or glass. Heating may be accomplished by electrical heating elements or by solar heating.

Municipal waste processing apparatus

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

Mayberry, J L

1987-01-15

Municipal waste materials are processed by crushing the materials so that pieces of noncombustible material are smaller than a selected size and pieces of combustible material are larger than the selected size. The crushed materials are placed on a vibrating mesh screen conveyor belt having openings which pass the smaller, noncombustible pieces of material, but do not pass the larger, combustible pieces of material. Pieces of material which become lodged in the openings of the conveyor belt may be removed by cylindrical deraggers or pressurized air. The crushed materials may be fed onto the conveyor belt by a vibrating feedmore » plate which shakes the materials so that they tend to lie flat.« less

Method for manufacturing lightning strike mitigation composites

NASA Technical Reports Server (NTRS)

Vaidyanathan, K. Ranji (Inventor); Campbell, Jeffrey (Inventor)

2012-01-01

A method for manufacturing a composite material utilizes a tooling material having a desired shape. The surface of the tooling material is coated with a composite film that includes a conductive filler material. A composite composition is introduced into contact with the surface of the tooling material to form a desired shape. The composite composition is processed to produce the composite material, and the composite material has a conductive composite surface layer that includes the conductive filler material.

Developing Maritime Thematic Expressions on English Reading Materials Used In Indonesia: Junior High School Context

NASA Astrophysics Data System (ADS)

Syahdan; Lusandi, Budi

2018-05-01

Indonesia is a maritime country with the largest islands in the world covering more than seventeen thousands islands. This wealth should be wisely explored for all their advantages. Also, all parties should take responsibility to inherit values embedded in the wealth. This study is a Research and Development focusing at developing English worksheet materials in the theme of Maritime Thematic Expressions. Specifically, it aimed at identifying initial contents of the English worksheet, describing the development of worksheet materials and justifying contents of worksheet materials in facilitating the students’ needs in reading English materials. The flow of this R&D refers to Sugiono’s model that includes analyzing data, collecting data, designing materials, validating material, revising the material, piloting products, revising the material, piloting materials, revising the material and material development. The development of this material adjusted to the needs of syllabus and national strategic issues in maritime that were coined with students of Junior High School Terbuka Pekanbaru. The worsksheet development has been revised and validated by some experts of curriculum and linguistics. This material has also been piloted by the English teacher to determine of the students’ ability in comprehending the materials. Based on the results of this development, it can be concluded that the materials development were relevant with the standard competence and basic competence in syllabus of the students’ reading skill in Junior High School Terbuka Pekanbaru.

Toughened and corrosion- and wear-resistant composite structures and fabrication methods thereof

DOEpatents

Seals, Roland D; Ripley, Edward B; Hallman, Russell L

2014-04-08

Composite structures having a reinforced material interjoined with a substrate and methods of creating a composite material interjoined with a substrate. In some embodiments the composite structure may be a line or a spot or formed by reinforced material interjoined with the substrate. The methods typically include disposing a precursor material comprising titanium diboride and/or titanium monoboride on at least a portion of the substrate and heating the precursor material and the at least a portion of the substrate in the presence of an oxidation preventative until at least a portion of the precursor material forms reinforced material interjoined with the substrate. The precursor material may be disposed on the substrate as a sheet or a tape or a slurry or a paste. Localized surface heating may be used to heat the precursor material. The reinforced material typically comprises a titanium boron compound, such as titanium monoboride, and preferably comprises .beta.-titanium. The substrate is typically titanium-bearing, iron-bearing, or aluminum-bearing. A welding rod is provided as an embodiment. The welding rod includes a metal electrode and a precursor material is disposed adjacent at least a portion of the metal electrode. A material for use in forming a composite structure is provided. The material typically includes a precursor material that includes one or more materials selected from the following group: titanium diboride and titanium monoboride. The material also typically includes a flux.

Materials with structural hierarchy

NASA Technical Reports Server (NTRS)

Lakes, Roderic

1993-01-01

The role of structural hierarchy in determining bulk material properties is examined. Dense hierarchical materials are discussed, including composites and polycrystals, polymers, and biological materials. Hierarchical cellular materials are considered, including cellular solids and the prediction of strength and stiffness in hierarchical cellular materials.

42 CFR 423.2260 - Definitions concerning marketing materials.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 3 2011-10-01 2011-10-01 false Definitions concerning marketing materials. 423... Marketing Requirements § 423.2260 Definitions concerning marketing materials. As used in this subpart— Marketing materials. Marketing Materials include any informational materials targeted to Medicare...

42 CFR 422.2260 - Definitions concerning marketing materials.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 3 2012-10-01 2012-10-01 false Definitions concerning marketing materials. 422... Marketing Requirements § 422.2260 Definitions concerning marketing materials. As used in this subpart— Marketing materials. Marketing materials include any informational materials targeted to Medicare...

42 CFR 422.2260 - Definitions concerning marketing materials.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 3 2014-10-01 2014-10-01 false Definitions concerning marketing materials. 422... Marketing Requirements § 422.2260 Definitions concerning marketing materials. As used in this subpart— Marketing materials. Marketing materials include any informational materials targeted to Medicare...

42 CFR 422.2260 - Definitions concerning marketing materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 3 2013-10-01 2013-10-01 false Definitions concerning marketing materials. 422... Marketing Requirements § 422.2260 Definitions concerning marketing materials. As used in this subpart— Marketing materials. Marketing materials include any informational materials targeted to Medicare...

Multifunctional materials and composites

DOEpatents

Seo, Dong-Kyun; Jeon, Ki-Wan

2017-08-22

Forming multifunctional materials and composites thereof includes contacting a first material having a plurality of oxygen-containing functional groups with a chalcogenide compound, and initiating a chemical reaction between the first material and the chalcogenide compound, thereby replacing oxygen in some of the oxygen-containing functional groups with chalcogen from the chalcogen-containing compound to yield a second material having chalcogen-containing functional groups and oxygen-containing functional groups. The first material is a carbonaceous material or a macromolecular material. A product including the second material is collected and may be processed further to yield a modified product or a composite.

Substrate Structures For Growth Of Highly Oriented And/Or Epitaxial Layers Thereon

DOEpatents

Arendt, Paul N.; Foltyn, Stephen R.; Groves, James R.; Jia, Quanxi

2005-07-26

A composite substrate structure including a substrate, a layer of a crystalline metal oxide or crystalline metal oxynitride material upon the substrate, a layer of an oriented cubic oxide material having a rock-salt-like structure upon the crystalline metal oxide or crystalline metal oxynitride material layer is provided together with additional layers such as one or more layers of a buffer material upon the oriented cubic oxide material layer. Jc's of 2.3×106 A/cm2 have been demonstrated with projected Ic's of 320 Amperes across a sample 1 cm wide for a superconducting article including a flexible polycrystalline metallic substrate, an inert oxide material layer upon the surface of the flexible polycrystalline metallic substrate, a layer of a crystalline metal oxide or crystalline metal oxynitride material upon the layer of the inert oxide material, a layer of an oriented cubic oxide material having a rock-salt-like structure upon the crystalline metal oxide or crystalline metal oxynitride material layer, a layer of a buffer material upon the oriented cubic oxide material layer, and, a top-layer of a high temperature superconducting material upon the layer of a buffer material.

Comparative study on stiffness properties of WOODCAST and conventional casting materials.

PubMed

Pirhonen, Eija; Pärssinen, Antti; Pelto, Mika

2013-08-01

Plaster-of-Paris and synthetic materials (e.g. fibreglass) have been in clinical use as casting materials for decades. An innovative casting material, WOODCAST, brings interesting alternatives to the traditional materials. The aim of this study was to compare the stiffness properties of the WOODCAST material to traditional casting materials. In immobilization by casting, materials with variable stiffness properties are required. Ring stiffness of cylindrical samples correlates well with cast rigidity. For load-bearing structures, the use of the WOODCAST Splint is recommended as equally high stiffness was obtained with the WOODCAST Splint as was with fibreglass. The WOODCAST 2 mm product is optimal for structures where some elasticity is required, and WOODCAST Ribbon can be used in any WOODCAST structure where further reinforcement is needed. The results show that WOODCAST material can be used in replacing traditional casting materials used in extremity immobilization. The mechanical properties of casting material play an important role in safe and effective fracture immobilization. Stiffness properties of the WOODCAST casting material and conventional materials - fibreglass and plaster-of-Paris - were analysed in this study. The WOODCAST Splint appears to compare favorably with traditional materials such as Scotchcast.

Materiomics: biological protein materials, from nano to macro.

PubMed

Cranford, Steven; Buehler, Markus J

2010-11-12

Materiomics is an emerging field of science that provides a basis for multiscale material system characterization, inspired in part by natural, for example, protein-based materials. Here we outline the scope and explain the motivation of the field of materiomics, as well as demonstrate the benefits of a materiomic approach in the understanding of biological and natural materials as well as in the design of de novo materials. We discuss recent studies that exemplify the impact of materiomics - discovering Nature's complexity through a materials science approach that merges concepts of material and structure throughout all scales and incorporates feedback loops that facilitate sensing and resulting structural changes at multiple scales. The development and application of materiomics is illustrated for the specific case of protein-based materials, which constitute the building blocks of a variety of biological systems such as tendon, bone, skin, spider silk, cells, and tissue, as well as natural composite material systems (a combination of protein-based and inorganic constituents) such as nacre and mollusk shells, and other natural multiscale systems such as cellulose-based plant and wood materials. An important trait of these materials is that they display distinctive hierarchical structures across multiple scales, where molecular details are exhibited in macroscale mechanical responses. Protein materials are intriguing examples of materials that balance multiple tasks, representing some of the most sustainable material solutions that integrate structure and function despite severe limitations in the quality and quantity of material building blocks. However, up until now, our attempts to analyze and replicate Nature's materials have been hindered by our lack of fundamental understanding of these materials' intricate hierarchical structures, scale-bridging mechanisms, and complex material components that bestow protein-based materials their unique properties. Recent advances in analytical tools and experimental methods allow a holistic view of such a hierarchical biological material system. The integration of these approaches and amalgamation of material properties at all scale levels to develop a complete description of a material system falls within the emerging field of materiomics. Materiomics is the result of the convergence of engineering and materials science with experimental and computational biology in the context of natural and synthetic materials. Through materiomics, fundamental advances in our understanding of structure-property-process relations of biological systems contribute to the mechanistic understanding of certain diseases and facilitate the development of novel biological, biologically inspired, and completely synthetic materials for applications in medicine (biomaterials), nanotechnology, and engineering.

Biological materials by design.

PubMed

Qin, Zhao; Dimas, Leon; Adler, David; Bratzel, Graham; Buehler, Markus J

2014-02-19

In this topical review we discuss recent advances in the use of physical insight into the way biological materials function, to design novel engineered materials 'from scratch', or from the level of fundamental building blocks upwards and by using computational multiscale methods that link chemistry to material function. We present studies that connect advances in multiscale hierarchical material structuring with material synthesis and testing, review case studies of wood and other biological materials, and illustrate how engineered fiber composites and bulk materials are designed, modeled, and then synthesized and tested experimentally. The integration of experiment and simulation in multiscale design opens new avenues to explore the physics of materials from a fundamental perspective, and using complementary strengths from models and empirical techniques. Recent developments in this field illustrate a new paradigm by which complex material functionality is achieved through hierarchical structuring in spite of simple material constituents.

Doped Chiral Polymer Metamaterials

NASA Technical Reports Server (NTRS)

Kang, Jin Ho (Inventor); Gordon, Keith L. (Inventor); Sauti, Godfrey (Inventor); Bryant, Robert G. (Inventor); Park, Cheol (Inventor); Lowther, Sharon E. (Inventor)

2017-01-01

Some implementations provide a composite material that includes a first material and a second material. In some implementations, the composite material is a metamaterial. The first material includes a chiral polymer (e.g., crystalline chiral helical polymer, poly-.gamma.-benzyl-L-glutamate (PBLG), poly-L-lactic acid (PLA), polypeptide, and/or polyacetylene). The second material is within the chiral polymer. The first material and the second material are configured to provide an effective index of refraction value for the composite material of 1 or less. In some implementations, the effective index of refraction value for the composite material is negative. In some implementations, the effective index of refraction value for the composite material of 1 or less is at least in a wavelength of one of at least a visible spectrum, an infrared spectrum, a microwave spectrum, and/or an ultraviolet spectrum.

System and method for producing metallic iron

DOEpatents

Englund, David J.; Schlichting, Mark; Meehan, John; Crouch, Jeremiah; Wilson, Logan

2014-07-29

A method of production of metallic iron nodules comprises assembling a hearth furnace having a moveable hearth comprising refractory material and having a conversion zone and a fusion zone, providing a hearth material layer comprising carbonaceous material on the refractory material, providing a layer of reducible material comprising and iron bearing material arranged in discrete portions over at least a portion of the hearth material layer, delivering oxygen gas into the hearth furnace to a ratio of at least 0.8:1 ponds of oxygen to pounds of iron in the reducible material to heat the conversion zone to a temperature sufficient to at least partially reduce the reducible material and to heat the fusion zone to a temperature sufficient to at least partially reduce the reducible material, and heating the reducible material to form one or more metallic iron nodules and slag.

77 FR 60935 - Hazardous Materials: Minor Editorial Corrections and Clarifications (RRR)

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-05

... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration 49 CFR Parts... Materials: Minor Editorial Corrections and Clarifications (RRR) AGENCY: Pipeline and Hazardous Materials... material. (a) * * * (3) * * * Source and name of material 49 CFR reference * * * * * * * ISO 9809-1: Gas...

42 CFR 423.2260 - Definitions concerning marketing materials.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 3 2012-10-01 2012-10-01 false Definitions concerning marketing materials. 423... Part D Marketing Requirements § 423.2260 Definitions concerning marketing materials. As used in this subpart— Marketing materials. Marketing Materials include any informational materials targeted to Medicare...

42 CFR 423.2260 - Definitions concerning marketing materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 3 2013-10-01 2013-10-01 false Definitions concerning marketing materials. 423... Part D Marketing Requirements § 423.2260 Definitions concerning marketing materials. As used in this subpart— Marketing materials. Marketing Materials include any informational materials targeted to Medicare...

42 CFR 423.2260 - Definitions concerning marketing materials.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 3 2014-10-01 2014-10-01 false Definitions concerning marketing materials. 423... Part D Marketing Requirements § 423.2260 Definitions concerning marketing materials. As used in this subpart— Marketing materials. Marketing Materials include any informational materials targeted to Medicare...

Municipal waste processing apparatus

DOEpatents

Mayberry, John L.

1989-01-01

Municipal waste materials are processed by crushing the materials so that pieces of noncombustible material are smaller than a selected size and pieces of combustible material are larger than the selected size. The crushed materials are placed on a vibrating mesh screen conveyor belt having openings which pass the smaller, noncombustible pieces of material, but do not pass the larger, combustible pieces of material. Consecutive conveyors may be connected by an intermediate vibratory plate. An air knife can be used to further separate materials based on weight.

Damascene fabrication of nonplanar microcoils

DOEpatents

Adams, David P.; Vasile, Michael J.

2003-06-17

A process for fabricating coils using a Damascene process uses a curved substrate having a surface extending along and about an axis made of a first material. A groove is formed in the curved surface along and around said axis, and the groove is filled with a second material that is different from the first material to form a coil of second material in said first material. Excess second material is then removed from the surface of the first material, leaving the coil of second material in the groove.

Gas storage materials, including hydrogen storage materials

DOEpatents

Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

2013-02-19

A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

Gas storage materials, including hydrogen storage materials

DOEpatents

Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

2014-11-25

A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material, such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

Article and process for producing an article

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

Lacy, Benjamin Paul; Jacala, Ariel Caesar Prepena; Kottilingam, Srikanth Chandrudu

An article and a process of producing an article are provided. The article includes a base material, a cooling feature arrangement positioned on the base material, the cooling feature arrangement including an additive-structured material, and a cover material. The cooling feature arrangement is between the base material and the cover material. The process of producing the article includes manufacturing a cooling feature arrangement by an additive manufacturing technique, and then positioning the cooling feature arrangement between a base material and a cover material.

Materials Requirements for Advanced Propulsion Systems

NASA Technical Reports Server (NTRS)

Whitaker, Ann F.; Cook, Mary Beth; Clinton, R. G., Jr.

2005-01-01

NASA's mission to "reach the Moon and Mars" will be obtained only if research begins now to develop materials with expanded capabilities to reduce mass, cost and risk to the program. Current materials cannot function satisfactorily in the deep space environments and do not meet the requirements of long term space propulsion concepts for manned missions. Directed research is needed to better understand materials behavior for optimizing their processing. This research, generating a deeper understanding of material behavior, can lead to enhanced implementation of materials for future exploration vehicles. materials providing new approaches for manufacture and new options for In response to this need for more robust materials, NASA's Exploration Systems Mission Directorate (ESMD) has established a strategic research initiative dedicated to materials development supporting NASA's space propulsion needs. The Advanced Materials for Exploration (AME) element directs basic and applied research to understand material behavior and develop improved materials allowing propulsion systems to operate beyond their current limitations. This paper will discuss the approach used to direct the path of strategic research for advanced materials to ensure that the research is indeed supportive of NASA's future missions to the moon, Mars, and beyond.

Materials Informatics: Statistical Modeling in Material Science.

PubMed

Yosipof, Abraham; Shimanovich, Klimentiy; Senderowitz, Hanoch

2016-12-01

Material informatics is engaged with the application of informatic principles to materials science in order to assist in the discovery and development of new materials. Central to the field is the application of data mining techniques and in particular machine learning approaches, often referred to as Quantitative Structure Activity Relationship (QSAR) modeling, to derive predictive models for a variety of materials-related "activities". Such models can accelerate the development of new materials with favorable properties and provide insight into the factors governing these properties. Here we provide a comparison between medicinal chemistry/drug design and materials-related QSAR modeling and highlight the importance of developing new, materials-specific descriptors. We survey some of the most recent QSAR models developed in materials science with focus on energetic materials and on solar cells. Finally we present new examples of material-informatic analyses of solar cells libraries produced from metal oxides using combinatorial material synthesis. Different analyses lead to interesting physical insights as well as to the design of new cells with potentially improved photovoltaic parameters. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Magnetorheological materials, method for making, and applications thereof

DOEpatents

Shen, Rui; Yang, Hong; Shafrir, Shai N.; Miao, Chunlin; Wang, Mimi; Mici, Joni; Lambropoulos, John C.; Jacobs, Stephen D.

2014-08-19

A magnetorheological material comprises a magnetic particle and a ceramic material, wherein the magnetorheological material is in a dried form and further wherein a portion of the ceramic material is in the form of a nanocrystalline coating over the entire exterior surface of the magnetic particle and another portion of the ceramic material is in the form of a free nanocrystal. A magnetorheological material comprises a magnetic particle having a ceramic material coating over an external surface thereof as a result of a coating process, and a free nanocrystal of the ceramic material in the form of a residual by-product of the coating process. A sol-gel process for making a magnetorheological product comprises providing a sol of a desired ceramic coating material; combining a desired quantity of carbonyl iron (CI) particles with the sol to coat the CI particles with the ceramic coating material; creating a resulting quantity of nanocrystalline ceramic material-coated CI particles and a quantity of free nanocrystals of the ceramic material; and, drying the resulting quantity of coated CI particles and free nanocrystals to a moisture content equal to or less than 2 wt %.

Hazardous Material Packaging and Transportation

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

Hypes, Philip A.

2016-02-04

This is a student training course. Some course objectives are to: recognize and use standard international and US customary units to describe activities and exposure rates associated with radioactive material; determine whether a quantity of a single radionuclide meets the definition of a class 7 (radioactive) material; determine, for a given single radionuclide, the shipping quantity activity limits per 49 Code of Federal Regulations (CFR) 173.435; determine the appropriate radioactive material hazard class proper shipping name for a given material; determine when a single radionuclide meets the DOT definition of a hazardous substance; determine the appropriate packaging required for amore » given radioactive material; identify the markings to be placed on a package of radioactive material; determine the label(s) to apply to a given radioactive material package; identify the entry requirements for radioactive material labels; determine the proper placement for radioactive material label(s); identify the shipping paper entry requirements for radioactive material; select the appropriate placards for a given radioactive material shipment or vehicle load; and identify allowable transport limits and unacceptable transport conditions for radioactive material.« less

Molecular level studies on interfacial hydration of zwitterionic and other antifouling polymers in situ.

PubMed

Leng, Chuan; Sun, Shuwen; Zhang, Kexin; Jiang, Shaoyi; Chen, Zhan

2016-08-01

Antifouling polymers have wide applications in biomedical engineering and marine industry. Recently, zwitterionic materials have been reported as promising candidates for antifouling applications, while strong hydration is believed to be the key antifouling mechanism. Zwitterionic materials can be designed with various molecular structures, which affect their hydration and antifouling performance. Although strong hydration has been proposed to occur at the material surfaces, probing the solid material/water interfaces is challenging with traditional analytical techniques. Here in this review, we will review our studies on surface hydration of zwitterionic materials and other antifouling materials by using sum frequency generation (SFG) vibrational spectroscopy, which provides molecular understanding of the water structures at various material surfaces. The materials studied include zwitterionic polymer brushes with different molecular structures, amphiphilic polymers with zwitterionic groups, uncharged hydrophilic polymer brushes, amphiphilic polypeptoids, and widely used antifouling material poly(ethylene glycol). We will compare the differences among zwitterionic materials with various molecular structures as well as the differences between antifouling materials and fouling surfaces of control samples. We will also discuss the effects of pH and biological molecules like proteins on the surface hydration of the zwitterionic materials. Using SFG spectroscopy, we have measured the hydration layers of antifouling materials and found that strong hydrogen bonds are key to the formation of strong hydration layers preventing protein fouling at the polymer interfaces. Antifouling polymers have wide applications in biomedical engineering and marine industry. Recently, zwitterionic materials have been reported as promising candidates for antifouling applications, while strong hydration is believed to be the key antifouling mechanism. However, zwitterionic materials can be designed with various molecular structures, which affect their hydration and antifouling performance. Moreover, although strong hydration has been proposed to occur at the material surfaces, probing the solid material/water interfaces is challenging with traditional analytical techniques. Here in this manuscript, we will review our studies on surface hydration of zwitterionic materials and other antifouling materials by using sum frequency generation (SFG) vibrational spectroscopy, which provides molecular understanding of the water structures at various material surfaces. The materials studied include zwitterionic polymer brushes with different molecular structures, amphiphilic polymers with zwitterionic groups, uncharged hydrophilic polymer brushes, amphiphilic polypeptoids, and widely used antifouling material poly(ethylene glycol). We will compare the differences among zwitterionic materials with various molecular structures as well as the differences between antifouling materials and fouling surfaces of control samples. We will also discuss the effects of pH and biological molecules like proteins on the surface hydration of the zwitterionic materials. All the SFG results indicate that strongly hydrogen-bonded water at the materials' surfaces (strong surface hydration) is closely correlated to the good antifouling properties of the materials. This review will be widely interested by readers of Acta Biomaterialia and will impact many different research fields in chemistry, materials, engineering, and beyond. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Cybermaterials: materials by design and accelerated insertion of materials

NASA Astrophysics Data System (ADS)

Xiong, Wei; Olson, Gregory B.

2016-02-01

Cybermaterials innovation entails an integration of Materials by Design and accelerated insertion of materials (AIM), which transfers studio ideation into industrial manufacturing. By assembling a hierarchical architecture of integrated computational materials design (ICMD) based on materials genomic fundamental databases, the ICMD mechanistic design models accelerate innovation. We here review progress in the development of linkage models of the process-structure-property-performance paradigm, as well as related design accelerating tools. Extending the materials development capability based on phase-level structural control requires more fundamental investment at the level of the Materials Genome, with focus on improving applicable parametric design models and constructing high-quality databases. Future opportunities in materials genomic research serving both Materials by Design and AIM are addressed.

2004 research briefs :Materials and Process Sciences Center.

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

Cieslak, Michael J.

2004-01-01

This report is the latest in a continuing series that highlights the recent technical accomplishments associated with the work being performed within the Materials and Process Sciences Center. Our research and development activities primarily address the materials-engineering needs of Sandia's Nuclear-Weapons (NW) program. In addition, we have significant efforts that support programs managed by the other laboratory business units. Our wide range of activities occurs within six thematic areas: Materials Aging and Reliability, Scientifically Engineered Materials, Materials Processing, Materials Characterization, Materials for Microsystems, and Materials Modeling and Simulation. We believe these highlights collectively demonstrate the importance that a strong materials-sciencemore » base has on the ultimate success of the NW program and the overall DOE technology portfolio.« less

Pressure induced swelling in microporous materials

DOEpatents

Vogt, Thomas; Hriljac, Joseph A.; Lee, Yongjae

2006-07-11

A method for capturing specified materials which includes contacting a microporous material with a hydrostatic fluid having at least one specified material carried therein, under pressure which structurally distorts the lattice sufficiently to permit entry of the at least one specified material. The microporous material is capable of undergoing a temporary structural distortion which alters resting lattice dimensions under increased ambient pressure and at least partially returning to rest lattice dimensions when returned to ambient pressure. The pressure of the fluid is then reduced to permit return to at least partial resting lattice dimension while the at least one specified material is therein. By this method, at least one specified material is captured in the microporous material to form a modified microporous material.

Electrode materials

DOEpatents

Amine, Khalil; Abouimrane, Ali; Belharouak, Ilias

2017-01-31

A process for forming a surface-treatment layer on an electroactive material includes heating the electroactive material and exposing the electroactive material to a reducing gas to form a surface-treatment layer on the electroactive material, where the surface-treatment layer is a layer of partial reduction of the electroactive material.

14 CFR 25.856 - Thermal/Acoustic insulation materials.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Thermal/Acoustic insulation materials. 25....856 Thermal/Acoustic insulation materials. (a) Thermal/acoustic insulation material installed in the.../acoustic insulation materials (including the means of fastening the materials to the fuselage) installed in...

THE EFFECT OF VENTILATION ON EMISSION RATES OF WOOD FINISHING MATERIALS

EPA Science Inventory

The rate of emission of organic compounds from building materials varies according to: type of material, material loading (area of material/volume of room), compound emitted, temperature, humidity, and ventilation rate. For some compounds and materials (e.g., formaldehyde from pa...

48 CFR 52.211-5 - Material Requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... materials and by-products generated from, and reused within, an original manufacturing process; provided... readjustments and material replacement. Recovered material means waste materials and by-products recovered or diverted from solid waste, but the term does not include those materials and by-products generated from...

Composite solid-state scintillators for neutron detection

DOEpatents

Dai, Sheng; Im, Hee-Jung; Pawel, Michelle D.

2006-09-12

Applicant's present invention is a composite scintillator for neutron detection comprising a matrix material fabricated from an inorganic sol-gel precursor solution homogeneously doped with a liquid scintillating material and a neutron absorbing material. The neutron absorbing material yields at least one of an electron, a proton, a triton, an alpha particle or a fission fragment when the neutron absorbing material absorbs a neutron. The composite scintillator further comprises a liquid scintillating material in a self-assembled micelle formation homogeneously doped in the matrix material through the formation of surfactant-silica composites. The scintillating material is provided to scintillate when traversed by at least one of an electron, a proton, a triton, an alpha particle or a fission fragment. The scintillating material is configured such that the matrix material surrounds the micelle formation of the scintillating material. The composite scintillator is fabricated and applied as a thin film on substrate surfaces, a coating on optical fibers or as a glass material.

Antithrombotic Protein Filter Composed of Hybrid Tissue-Fabric Material has a Long Lifetime.

PubMed

Inoue, Yusuke; Yokota, Tomoyuki; Sekitani, Tsuyoshi; Kaneko, Akiko; Woo, Taeseong; Kobayashi, Shingo; Shibuya, Tomokazu; Tanaka, Masaru; Kosukegawa, Hiroyuki; Saito, Itsuro; Isoyama, Takashi; Abe, Yusuke; Yambe, Tomoyuki; Someya, Takao; Sekino, Masaki

2017-05-01

There are recent reports of hybrid tissue-fabric materials with good performance-high biocompatibility and high mechanical strength. In this study, we demonstrate the capability of a hybrid material as a long-term filter for blood proteins. Polyester fabrics were implanted into rats to fabricate hybrid tissue-fabric material sheets. The hybrid materials comprised biological tissue grown on the fabric. The materials were extracted from the rat's body, approximately 100 days post-implantation. The tissues were decellularized to prevent immunological rejection. An antithrombogenicity test was performed by dropping blood onto the hybrid material surface. The hybrid material showed lesser blood coagulation than polysulfone and cellulose. Blood plasma was filtered using the hybrid material to evaluate the protein removal percentage and the lifetime of the hybrid material in vitro. The hybrid material showed a comparable performance to conventional filters for protein removal. Moreover, the hybrid material could work as a protein filter for 1 month, which is six times the lifetime of polysulfone.

Combinatorial materials approach to accelerate materials discovery for transportation (Conference Presentation)

NASA Astrophysics Data System (ADS)

Tong, Wei

2017-04-01

Combinatorial material research offers fast and efficient solutions to identify promising and advanced materials. It has revolutionized the pharmaceutical industry and now is being applied to accelerate the discovery of other new compounds, e.g. superconductors, luminescent materials, catalysts etc. Differing from the traditional trial-and-error process, this approach allows for the synthesis of a large number of compositionally diverse compounds by varying the combinations of the components and adjusting the ratios. It largely reduces the cost of single-sample synthesis/characterization, along with the turnaround time in the material discovery process, therefore, could dramatically change the existing paradigm for discovering and commercializing new materials. This talk outlines the use of combinatorial materials approach in the material discovery in transportation sector. It covers the general introduction to the combinatorial material concept, state of art for its application in energy-related research. At the end, LBNL capabilities in combinatorial materials synthesis and high throughput characterization that are applicable for material discovery research will be highlighted.

Technology assessment of solar-energy systems. Materials resource and hazardous materials impacts of solar deployment

NASA Astrophysics Data System (ADS)

Schiffman, Y. M.; Tahami, J. E.

1982-04-01

The materials-resource and hazardous-materials impacts were determined by examining the type and quantity of materials used in the manufacture, construction, installation, operation and maintenance of solar systems. The materials requirements were compared with US materials supply and demand data to determine if potential problems exist in terms of future availability of domestic supply and increased dependence on foreign sources of supply. Hazardous materials were evaluated in terms of public and occupational health hazards and explosive and fire hazards. It is concluded that: although large amounts of materials would be required, the US had sufficient industrial capacity to produce those materials; (2) postulated growth in solar technology deployment during the period 1995-2000 could cause some production shortfalls in the steel and copper industry; the U.S. could increase its import reliance for certain materials such as silver, iron ore, and copper; however, shifts to other materials such as aluminum and polyvinylchloride could alleviate some of these problems.

Low resistance thin film organic solar cell electrodes

DOEpatents

Forrest, Stephen [Princeton, NJ; Xue, Jiangeng [Piscataway, NJ

2008-01-01

A method which lower the series resistance of photosensitive devices includes providing a transparent film of a first electrically conductive material arranged on a transparent substrate; depositing and patterning a mask over the first electrically conductive material, such that openings in the mask have sloping sides which narrow approaching the substrate; depositing a second electrically conductive material directly onto the first electrically conductive material exposed in the openings of the mask, at least partially filling the openings; stripping the mask, leaving behind reentrant structures of the second electrically conductive material which were formed by the deposits in the openings of the mask; after stripping the mask, depositing a first organic material onto the first electrically conductive material in between the reentrant structures; and directionally depositing a third electrically conductive material over the first organic material deposited in between the reentrant structures, edges of the reentrant structures aligning deposition so that the third electrically conductive material does not directly contact the first electrically conductive material, and does not directly contact the second electrically conductive material.

Purification of metal-organic framework materials

DOEpatents

Farha, Omar K.; Hupp, Joseph T.

2012-12-04

A method of purification of a solid mixture of a metal-organic framework (MOF) material and an unwanted second material by disposing the solid mixture in a liquid separation medium having a density that lies between those of the wanted MOF material and the unwanted material, whereby the solid mixture separates by density differences into a fraction of wanted MOF material and another fraction of unwanted material.

Magnetic Field-Induced Phase Transformation in Magnetic Shape Memory Alloys with High Actuation Stress and Work Output

DTIC Science & Technology

2010-05-03

Mechanisms for Advanced Properties in Phase Transforming Materials , Materials Science & Technology 2009 Conference, October 25-29, 2009, Pittsburgh, PA...Advanced Properties in Phase Transforming Materials , Materials Science & Technology 2009 Conference, October 25-29, 2009, Pittsburgh, PA, 2009. 11...observed materials behavior. Indeed, measured materials properties were found not to be the exact indication of the materials real response

Purification of metal-organic framework materials

DOEpatents

Farha, Omar K.; Hupp, Joseph T.

2015-06-30

A method of purification of a solid mixture of a metal-organic framework (MOF) material and an unwanted second material by disposing the solid mixture in a liquid separation medium having a density that lies between those of the wanted MOF material and the unwanted material, whereby the solid mixture separates by density differences into a fraction of wanted MOF material and another fraction of unwanted material.

Types of architectural structures and the use of smart materials

NASA Astrophysics Data System (ADS)

Tavşan, Cengiz; Sipahi, Serkan

2017-07-01

The developments in technology following the industrial revolution had their share of impact on both construction techniques, and material technologies. The change in the materials used by the construction industry brought along numerous innovations, which, in turn, took on an autonomous trend of development given the rise of nano-tech materials. Today, nano-tech materials are used extensively in numerous construction categories. Nano-tech materials, in general, are characterized by their reactionary nature, with the intent of repeating the reactions again and again under certain conditions. That is why nano-tech materials are often called smart materials. In construction industry, smart materials are categorized under 4 major perspectives: Shape-shifting smart materials, power generating smart materials, self-maintenance smart materials, and smart materials providing a high level of insulation. In architecture, various categories of construction often tend to exhibit their own approaches to design, materials, and construction techniques. This is a direct consequence of the need for different solutions for different functions. In this context, the use of technological materials should lead to the use of a set of smart materials for a given category of structures, while another category utilizes yet another set. In the present study, the smart materials used in specific categories of structures were reviewed with reference to nano-tech practices implemented in Europe, with a view to try and reveal the changes in the use of smart materials with reference to categories of structures. The study entails a discussion to test the hypothesis that nano-tech materials vary with reference to structure categories, on the basis of 18 examples from various structure categories, built by the construction firms with the highest level of potential in terms of doing business in Europe. The study comprises 3 major sections: The first section reiterates what the literature has to say about smart materials; the second discusses the types and characteristics of smart materials over the tables detailing their utilization and functions in the structures included in the set of examples. The final section of the study, on the other hand, elaborates on the findings, discussing them with reference to the types of structures.

Sorting it out: bedding particle size and nesting material processing method affect nest complexity.

PubMed

Robinson-Junker, Amy; Morin, Amelia; Pritchett-Corning, Kathleen; Gaskill, Brianna N

2017-04-01

As part of routine husbandry, an increasing number of laboratory mice receive nesting material in addition to standard bedding material in their cages. Nesting material improves health outcomes and physiological performance in mice that receive it. Providing usable nesting material uniformly and efficiently to various strains of mice remains a challenge. The aim of this study was to determine how bedding particle size, method of nesting material delivery, and processing of the nesting material before delivery affected nest building in mice of strong (BALB/cAnNCrl) and weak (C3H/HeNCrl) gathering abilities. Our data suggest that processing nesting material through a grinder in conjunction with bedding material, although convenient for provision of bedding with nesting material 'built-in', negatively affects the integrity of the nesting material and subsequent nest-building outcomes. We also found that C3H mice, previously thought to be poor nest builders, built similarly scored nests to those of BALB/c mice when provided with unprocessed nesting material. This was true even when nesting material was mixed into the bedding substrate. We also observed that when nesting material was mixed into the bedding substrate, mice of both strains would sort their bedding by particle size more often than if it were not mixed in. Our findings support the utility of the practice of distributing nesting material mixed in with bedding substrate, but not that of processing the nesting material with the bedding in order to mix them.

Method of making AlInSb by metal-organic chemical vapor deposition

DOEpatents

Biefeld, Robert M.; Allerman, Andrew A.; Baucom, Kevin C.

2000-01-01

A method for producing aluminum-indium-antimony materials by metal-organic chemical vapor deposition (MOCVD). This invention provides a method of producing Al.sub.X In.sub.1-x Sb crystalline materials by MOCVD wherein an Al source material, an In source material and an Sb source material are supplied as a gas to a heated substrate in a chamber, said Al source material, In source material, and Sb source material decomposing at least partially below 525.degree. C. to produce Al.sub.x In.sub.1-x Sb crystalline materials wherein x is greater than 0.002 and less than one.

Low-mass materials and vertex detector systems

DOE PAGES

Cooper, William E.

2014-01-01

Physics requirements set the material budget and the precision and stability necessary in low-mass vertex detector systems. Operational considerations, along with physics requirements, set the operating environment to be provided and determine the heat to be removed. Representative materials for fulfilling those requirements are described and properties of the materials are tabulated. A figure of merit is proposed to aid in material selection. Multi-layer structures are examined as a method to allow material to be used effectively, thereby reducing material contributions. Lastly, comments are made on future directions to be considered in using present materials effectively and in developing newmore » materials.« less

Augmented shock wave fracture/severance of materials

NASA Technical Reports Server (NTRS)

Schimmel, Morry L. (Inventor); Bement, Laurence J. (Inventor)

1995-01-01

The present invention related generally to severing materials, and more particularly to severing or weakening materials through explosively induced, augmented shock waves. Explosive cords are placed in grooves on the upper surface of the material to be severed or weakened. The explosive cords are initiated simultaneously to introduce explosive shock waves into the material. These shock waves progress toward the centerline between the explosive cords and the lower surface of the material. Intersecting and reflected waves produce a rarefaction zone on the centerline to fail the material in tension. A groove may also be cut in the lower surface of the material to aid in severing or weakening the material.

Rheology of Coating Materials and Their Coating Characteristics

NASA Astrophysics Data System (ADS)

Grabsch, C.; Grüner, S.; Otto, F.; Sommer, K.

2008-07-01

Lots of particles used in the pharmaceutical and the food industry are coated to protect the core material. But almost no investigations about the coating material behavior do exist. In this study the focus was on the rheological material properties of fat based coating materials. Rotational shear experiments to determine the viscosity of a material were compared to oscillatory shear tests to get information about the vicoelastic behavior of the coating materials. At the liquid state the viscosity and the viscoelastic properties showed a good analogy. The viscoelastic properties of the solid coating materials yielded differences between materials that have the same properties at the liquid state.

Embedded arrays of vertically aligned carbon nanotube carpets and methods for making them

DOEpatents

Kim, Myung Jong; Nicholas, Nolan Walker; Kittrell, W. Carter; Schmidt, Howard K.

2015-06-30

According to some embodiments, the present invention provides a system and method for supporting a carbon nanotube array that involve an entangled carbon nanotube mat integral with the array, where the mat is embedded in an embedding material. The embedding material may be depositable on a carbon nanotube. A depositable material may be metallic or nonmetallic. The embedding material may be an adhesive material. The adhesive material may optionally be mixed with a metal powder. The embedding material may be supported by a substrate or self-supportive. The embedding material may be conductive or nonconductive. The system and method provide superior mechanical and, when applicable, electrical, contact between the carbon nanotubes in the array and the embedding material. The optional use of a conductive material for the embedding material provides a mechanism useful for integration of carbon nanotube arrays into electronic devices.

Coincident site lattice-matched growth of semiconductors on substrates using compliant buffer layers

DOEpatents

Norman, Andrew

2016-08-23

A method of producing semiconductor materials and devices that incorporate the semiconductor materials are provided. In particular, a method is provided of producing a semiconductor material, such as a III-V semiconductor, on a silicon substrate using a compliant buffer layer, and devices such as photovoltaic cells that incorporate the semiconductor materials. The compliant buffer material and semiconductor materials may be deposited using coincident site lattice-matching epitaxy, resulting in a close degree of lattice matching between the substrate material and deposited material for a wide variety of material compositions. The coincident site lattice matching epitaxial process, as well as the use of a ductile buffer material, reduce the internal stresses and associated crystal defects within the deposited semiconductor materials fabricated using the disclosed method. As a result, the semiconductor devices provided herein possess enhanced performance characteristics due to a relatively low density of crystal defects.

The Materials Commons: A Collaboration Platform and Information Repository for the Global Materials Community

NASA Astrophysics Data System (ADS)

Puchala, Brian; Tarcea, Glenn; Marquis, Emmanuelle. A.; Hedstrom, Margaret; Jagadish, H. V.; Allison, John E.

2016-08-01

Accelerating the pace of materials discovery and development requires new approaches and means of collaborating and sharing information. To address this need, we are developing the Materials Commons, a collaboration platform and information repository for use by the structural materials community. The Materials Commons has been designed to be a continuous, seamless part of the scientific workflow process. Researchers upload the results of experiments and computations as they are performed, automatically where possible, along with the provenance information describing the experimental and computational processes. The Materials Commons website provides an easy-to-use interface for uploading and downloading data and data provenance, as well as for searching and sharing data. This paper provides an overview of the Materials Commons. Concepts are also outlined for integrating the Materials Commons with the broader Materials Information Infrastructure that is evolving to support the Materials Genome Initiative.

Strain-Detecting Composite Materials

NASA Technical Reports Server (NTRS)

Wallace, Terryl A. (Inventor); Smith, Stephen W. (Inventor); Piascik, Robert S. (Inventor); Horne, Michael R. (Inventor); Messick, Peter L. (Inventor); Alexa, Joel A. (Inventor); Glaessgen, Edward H. (Inventor); Hailer, Benjamin T. (Inventor)

2016-01-01

A composite material includes a structural material and a shape-memory alloy embedded in the structural material. The shape-memory alloy changes crystallographic phase from austenite to martensite in response to a predefined critical macroscopic average strain of the composite material. In a second embodiment, the composite material includes a plurality of particles of a ferromagnetic shape-memory alloy embedded in the structural material. The ferromagnetic shape-memory alloy changes crystallographic phase from austenite to martensite and changes magnetic phase in response to the predefined critical macroscopic average strain of the composite material. A method of forming a composite material for sensing the predefined critical macroscopic average strain includes providing the shape-memory alloy having an austenite crystallographic phase, changing a size and shape of the shape-memory alloy to thereby form a plurality of particles, and combining the structural material and the particles at a temperature of from about 100-700.degree. C. to form the composite material.

Preparation and characterization of phase transition/graphite foam composite materials.

PubMed

Yu, Jia; Tang, ChenLong; Yu, ZhiChao

2016-07-04

Phase transition/graphite foam (PCM/GF) composite materials are a kind of composite materials that fill graphite foam with phase change materials. In this paper, graphite foam was prepared firstly by the soft template method, the heat conductivity of which at room temperature is 5.44 W/(m∙K). Then, four phase change materials including eicosane, acetamide, xylitol, and erythritol were chosen for filling into the prepared graphite foam to obtain PCM/GF composite materials. Among the four kinds of materials, erythritol composite material has the highest melting point (118.5°C) and the highest enthalpy of fusion (266.3J/g), weight loss ratios of xylitol composite material after ten cycles is the lowest (2.1%), the compressive strength of xylitol composite material is the highest (9.08 MPa) and that of eicosane composite material is the lowest (3.32 MPa).

Local doping of two-dimensional materials

DOEpatents

Wong, Dillon; Velasco, Jr, Jairo; Ju, Long; Kahn, Salman; Lee, Juwon; Germany, Chad E.; Zettl, Alexander K.; Wang, Feng; Crommie, Michael F.

2016-09-20

This disclosure provides systems, methods, and apparatus related to locally doping two-dimensional (2D) materials. In one aspect, an assembly including a substrate, a first insulator disposed on the substrate, a second insulator disposed on the first insulator, and a 2D material disposed on the second insulator is formed. A first voltage is applied between the 2D material and the substrate. With the first voltage applied between the 2D material and the substrate, a second voltage is applied between the 2D material and a probe positioned proximate the 2D material. The second voltage between the 2D material and the probe is removed. The first voltage between the 2D material and the substrate is removed. A portion of the 2D material proximate the probe when the second voltage was applied has a different electron density compared to a remainder of the 2D material.

Passive absolute age and temperature history sensor

DOEpatents

Robinson, Alex; Vianco, Paul T.

2015-11-10

A passive sensor for historic age and temperature sensing, including a first member formed of a first material, the first material being either a metal or a semiconductor material and a second member formed of a second material, the second material being either a metal or a semiconductor material. A surface of the second member is in contact with a surface of the first member such that, over time, the second material of the second member diffuses into the first material of the first member. The rate of diffusion for the second material to diffuse into the first material depends on a temperature of the passive sensor. One of the electrical conductance, the electrical capacitance, the electrical inductance, the optical transmission, the optical reflectance, or the crystalline structure of the passive sensor depends on the amount of the second material that has diffused into the first member.

Electrochromic projection and writing device

DOEpatents

Branz, Howard M.; Benson, David K.

2002-01-01

A display and projection apparatus includes an electrochromic material and a photoconductive material deposited in tandem used in conjunction with a light filtering means for filtering light transmitted through the electrochromic material. When an electric field is applied across the electrochromic material and the photoconductive material, light that is incident onto the photoconductive material through the surface of the projection apparatus causes the photoconductive material to conduct current locally in proportion to the amount of light incident on the photoconductive material. The flow of current causes the underlying portions of the electrochromic material to switch from an opaque state to a clear or transmissive state, thereby allowing back-light to propagate through the electrochromic material to create a visible image on the surface of the projection apparatus. Reversal of the electric field causes the electrochromic material to revert back to its opaque state, thereby blocking the transmission of back-light and effectively erasing the image from the surface of the projection apparatus.

Hybrid vapor phase-solution phase growth techniques for improved CZT(S,Se) photovoltaic device performance

DOEpatents

Chang, Liang-Yi; Gershon, Talia S.; Haight, Richard A.; Lee, Yun Seog

2016-12-27

A hybrid vapor phase-solution phase CZT(S,Se) growth technique is provided. In one aspect, a method of forming a kesterite absorber material on a substrate includes the steps of: depositing a layer of a first kesterite material on the substrate using a vapor phase deposition process, wherein the first kesterite material includes Cu, Zn, Sn, and at least one of S and Se; annealing the first kesterite material to crystallize the first kesterite material; and depositing a layer of a second kesterite material on a side of the first kesterite material opposite the substrate using a solution phase deposition process, wherein the second kesterite material includes Cu, Zn, Sn, and at least one of S and Se, wherein the first kesterite material and the second kesterite material form a multi-layer stack of the absorber material on the substrate. A photovoltaic device and method of formation thereof are also provided.

Materials discovery through crystal growth

NASA Astrophysics Data System (ADS)

zur Loye, Hans-Conrad

2016-04-01

The discovery of new materials and associated desirable properties has been a driving force behind chemical innovation for centuries. When we look at some of the many recent technological advances, and how widespread and significant their impact has been, we appreciate how much they have relied on new materials. The increase in hard drive storage capacity due to new giant magneto-resistive materials, the ever-shrinking cell phone due to improved microwave dielectric materials, the enhancement in lithium battery storage capacity due to new intercalation materials, or the improved capacitor due to new ferroelectric materials are all excellent examples. How were these materials discovered? While there is no single answer, in all cases there was a First-Material, the archetype in which the phenomenon was first observed, the one that led to further investigations and the subsequent preparation of improved 2nd or 3rd generation materials. It is this First-Material, the archetype, that was discovered - often via crystal growth.

Electrochemical catalyst recovery method

DOEpatents

Silva, L.J.; Bray, L.A.

1995-05-30

A method of recovering catalyst material from latent catalyst material solids includes: (a) combining latent catalyst material solids with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form a mixture; (b) electrochemically oxidizing the redox material within the mixture into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the latent catalyst material; (c) reacting the oxidant with the latent catalyst material to oxidize the latent catalyst material into at least one oxidized catalyst species which is soluble within the mixture and to reduce the oxidant back into dissolved redox material; and (d) recovering catalyst material from the oxidized catalyst species of the mixture. The invention is expected to be particularly useful in recovering spent catalyst material from petroleum hydroprocessing reaction waste products having adhered sulfides, carbon, hydrocarbons, and undesired metals, and as well as in other industrial applications. 3 figs.

Electrochemical catalyst recovery method

DOEpatents

Silva, Laura J.; Bray, Lane A.

1995-01-01

A method of recovering catalyst material from latent catalyst material solids includes: a) combining latent catalyst material solids with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form a mixture; b) electrochemically oxidizing the redox material within the mixture into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the latent catalyst material; c) reacting the oxidant with the latent catalyst material to oxidize the latent catalyst material into at least one oxidized catalyst species which is soluble within the mixture and to reduce the oxidant back into dissolved redox material; and d) recovering catalyst material from the oxidized catalyst species of the mixture. The invention is expected to be particularly useful in recovering spent catalyst material from petroleum hydroprocessing reaction waste products having adhered sulfides, carbon, hydrocarbons, and undesired metals, and as well as in other industrial applications.

46 CFR 148.300 - Radioactive materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 5 2013-10-01 2013-10-01 false Radioactive materials. 148.300 Section 148.300 Shipping... MATERIALS THAT REQUIRE SPECIAL HANDLING Special Requirements for Certain Materials § 148.300 Radioactive materials. (a) Radioactive materials that may be stowed or transported in bulk are limited to those...

48 CFR 31.205-26 - Material costs.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Material costs. 31.205-26....205-26 Material costs. (a) Material costs include the costs of such items as raw materials, parts... material costs, the contractor shall consider reasonable overruns, spoilage, or defective work (unless...

48 CFR 31.205-26 - Material costs.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Material costs. 31.205-26....205-26 Material costs. (a) Material costs include the costs of such items as raw materials, parts... material costs, the contractor shall consider reasonable overruns, spoilage, or defective work (unless...

48 CFR 52.211-5 - Material Requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... readjustments and material replacement. Recovered material means waste materials and by-products recovered or diverted from solid waste, but the term does not include those materials and by-products generated from... is, or with new technology will become, a source of raw materials. (b) Unless this contract otherwise...

48 CFR 252.223-7001 - Hazard warning labels.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Hazardous Material Identification and Material Safety Data clause of this contract. (b) The Contractor shall label the item package (unit container) of any hazardous material to be delivered under this contract in... which hazardous material listed in the Hazardous Material Identification and Material Safety Data clause...

48 CFR 252.223-7001 - Hazard warning labels.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Hazardous Material Identification and Material Safety Data clause of this contract. (b) The Contractor shall label the item package (unit container) of any hazardous material to be delivered under this contract in... which hazardous material listed in the Hazardous Material Identification and Material Safety Data clause...

48 CFR 252.223-7001 - Hazard warning labels.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Hazardous Material Identification and Material Safety Data clause of this contract. (b) The Contractor shall label the item package (unit container) of any hazardous material to be delivered under this contract in... which hazardous material listed in the Hazardous Material Identification and Material Safety Data clause...

48 CFR 252.223-7001 - Hazard warning labels.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Hazardous Material Identification and Material Safety Data clause of this contract. (b) The Contractor shall label the item package (unit container) of any hazardous material to be delivered under this contract in... which hazardous material listed in the Hazardous Material Identification and Material Safety Data clause...

48 CFR 252.223-7001 - Hazard warning labels.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Hazardous Material Identification and Material Safety Data clause of this contract. (b) The Contractor shall label the item package (unit container) of any hazardous material to be delivered under this contract in... which hazardous material listed in the Hazardous Material Identification and Material Safety Data clause...

Materiomics: biological protein materials, from nano to macro

PubMed Central

Cranford, Steven; Buehler, Markus J

2010-01-01

Materiomics is an emerging field of science that provides a basis for multiscale material system characterization, inspired in part by natural, for example, protein-based materials. Here we outline the scope and explain the motivation of the field of materiomics, as well as demonstrate the benefits of a materiomic approach in the understanding of biological and natural materials as well as in the design of de novo materials. We discuss recent studies that exemplify the impact of materiomics – discovering Nature’s complexity through a materials science approach that merges concepts of material and structure throughout all scales and incorporates feedback loops that facilitate sensing and resulting structural changes at multiple scales. The development and application of materiomics is illustrated for the specific case of protein-based materials, which constitute the building blocks of a variety of biological systems such as tendon, bone, skin, spider silk, cells, and tissue, as well as natural composite material systems (a combination of protein-based and inorganic constituents) such as nacre and mollusk shells, and other natural multiscale systems such as cellulose-based plant and wood materials. An important trait of these materials is that they display distinctive hierarchical structures across multiple scales, where molecular details are exhibited in macroscale mechanical responses. Protein materials are intriguing examples of materials that balance multiple tasks, representing some of the most sustainable material solutions that integrate structure and function despite severe limitations in the quality and quantity of material building blocks. However, up until now, our attempts to analyze and replicate Nature’s materials have been hindered by our lack of fundamental understanding of these materials’ intricate hierarchical structures, scale-bridging mechanisms, and complex material components that bestow protein-based materials their unique properties. Recent advances in analytical tools and experimental methods allow a holistic view of such a hierarchical biological material system. The integration of these approaches and amalgamation of material properties at all scale levels to develop a complete description of a material system falls within the emerging field of materiomics. Materiomics is the result of the convergence of engineering and materials science with experimental and computational biology in the context of natural and synthetic materials. Through materiomics, fundamental advances in our understanding of structure–property–process relations of biological systems contribute to the mechanistic understanding of certain diseases and facilitate the development of novel biological, biologically inspired, and completely synthetic materials for applications in medicine (biomaterials), nanotechnology, and engineering. PMID:24198478

Phase change based cooling for high burst mode heat loads with temperature regulation above the phase change temperature

DOEpatents

The United States of America as represented by the United States Department of Energy

2009-12-15

An apparatus and method for transferring thermal energy from a heat load is disclosed. In particular, use of a phase change material and specific flow designs enables cooling with temperature regulation well above the fusion temperature of the phase change material for medium and high heat loads from devices operated intermittently (in burst mode). Exemplary heat loads include burst mode lasers and laser diodes, flight avionics, and high power space instruments. Thermal energy is transferred from the heat load to liquid phase change material from a phase change material reservoir. The liquid phase change material is split into two flows. Thermal energy is transferred from the first flow via a phase change material heat sink. The second flow bypasses the phase change material heat sink and joins with liquid phase change material exiting from the phase change material heat sink. The combined liquid phase change material is returned to the liquid phase change material reservoir. The ratio of bypass flow to flow into the phase change material heat sink can be varied to adjust the temperature of the liquid phase change material returned to the liquid phase change material reservoir. Varying the flowrate and temperature of the liquid phase change material presented to the heat load determines the magnitude of thermal energy transferred from the heat load.

Development of advanced high heat flux and plasma-facing materials

NASA Astrophysics Data System (ADS)

Linsmeier, Ch.; Rieth, M.; Aktaa, J.; Chikada, T.; Hoffmann, A.; Hoffmann, J.; Houben, A.; Kurishita, H.; Jin, X.; Li, M.; Litnovsky, A.; Matsuo, S.; von Müller, A.; Nikolic, V.; Palacios, T.; Pippan, R.; Qu, D.; Reiser, J.; Riesch, J.; Shikama, T.; Stieglitz, R.; Weber, T.; Wurster, S.; You, J.-H.; Zhou, Z.

2017-09-01

Plasma-facing materials and components in a fusion reactor are the interface between the plasma and the material part. The operational conditions in this environment are probably the most challenging parameters for any material: high power loads and large particle and neutron fluxes are simultaneously impinging at their surfaces. To realize fusion in a tokamak or stellarator reactor, given the proven geometries and technological solutions, requires an improvement of the thermo-mechanical capabilities of currently available materials. In its first part this article describes the requirements and needs for new, advanced materials for the plasma-facing components. Starting points are capabilities and limitations of tungsten-based alloys and structurally stabilized materials. Furthermore, material requirements from the fusion-specific loading scenarios of a divertor in a water-cooled configuration are described, defining directions for the material development. Finally, safety requirements for a fusion reactor with its specific accident scenarios and their potential environmental impact lead to the definition of inherently passive materials, avoiding release of radioactive material through intrinsic material properties. The second part of this article demonstrates current material development lines answering the fusion-specific requirements for high heat flux materials. New composite materials, in particular fiber-reinforced and laminated structures, as well as mechanically alloyed tungsten materials, allow the extension of the thermo-mechanical operation space towards regions of extreme steady-state and transient loads. Self-passivating tungsten alloys, demonstrating favorable tungsten-like plasma-wall interaction behavior under normal operation conditions, are an intrinsic solution to otherwise catastrophic consequences of loss-of-coolant and air ingress events in a fusion reactor. Permeation barrier layers avoid the escape of tritium into structural and cooling materials, thereby minimizing the release of tritium under normal operation conditions. Finally, solutions for the unique bonding requirements of dissimilar material used in a fusion reactor are demonstrated by describing the current status and prospects of functionally graded materials.

PREFACE 2nd International Conference on Materials Physics and Applications (JIPMA 2009/MATERIAUX 2009)

NASA Astrophysics Data System (ADS)

Cheikhrouhou, Abdelwaheb

2010-11-01

The 'Tunisian Materials Research Society: Tu-MRS' organized the International Days on Materials Physics and Applications 'JIPMA 2009' and the National Conference on Materials 'MATERIAUX 2009' in Gafsa (Tunisia) During the period 20-24 December 2009. The first International Days on Materials Physics and Applications 'JIPMA 2007' were organized in Annaba (Algeria) in November 2007 while the first National Conference on Materials 'MATERIAUX 2006' was organized in Douz (Tunisia) in December 2006. The 'JIPMA' conference series together with the 'MATERIAUX' intend to provide an excellent opportunity for international, Maghreb and Tunisian researchers to make their own works on materials known to a wider audience and to have discussions with other participants. This conference will also be an opportunity to exchange experiences, create and consolidate cooperation between different research structures in the Maghreb countries. This conference will equally promote research development, contribute to collaboration between universities and the socio-economical milieu. More than 300 senior researchers, Professors, PhD and Master students attended this conference from Tunisia, Algeria, Morocco, France, and Spain. Several researchers, engineers and managers from industrial firms also attended this scientific meeting. The conference consists of plenary and semi-plenary talks, oral contributions and poster presentations. The topics of the conference are: Nano-materials, nano-systems, thin films, surfaces and interfaces Multifonctional Materials, Magnetic Materials, Dielectric Materials, Superconducting Materials, Applications, ... Materials for Electronics, Informatics and Communications (Semi-conducting Materials, Electronic devices, Spintronic, ... Optoelectronic Materials, Sensors Ceramics, Glasses, Polymers, ... Natural Materials: Phosphates, Clay, ... Metallic Materials, alloys, ... Materials and Environment Materials and Energy Biomaterials Elaborating Methods and Characterization Techniques I want to thank the organizing committee and everyone else who participated in the organization of this meeting for their invaluable efforts to guarantee the full success of this conference. I want also to thank very warmly all the Scientific committee and all other reviewers for their hard work reviewing the submitted papers. Professor Abdelwaheb CHEIKHROUHOU Chairman of the Conference

76 FR 4276 - Hazardous Materials: Improving the Safety of Railroad Transportation of Hazardous Materials

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-25

...-0004] Hazardous Materials: Improving the Safety of Railroad Transportation of Hazardous Materials... hazardous materials program. DATES: The public meeting will be held on Tuesday, February 22, 2011, starting...--Hazardous Materials, FRA Office of Safety Assurance and Compliance, at least 4 business days before the date...

49 CFR 172.101 - Purpose and use of hazardous materials table.

Code of Federal Regulations, 2010 CFR

2010-10-01

... paragraph (c)(11): For the transportation of samples of self-reactive materials, organic peroxides... hazard class, the material is not a hazardous material. (13) Self-reactive materials and organic peroxides. A generic proper shipping name for a self-reactive material or an organic peroxide, as listed in...

Composites comprising biologically-synthesized nanomaterials

DOEpatents

Curran, Seamus; Dias, Sampath; Blau, Werner; Wang, Jun; Oremland, Ronald S; Baesman, Shaun

2013-04-30

The present disclosure describes composite materials containing a polymer material and a nanoscale material dispersed in the polymer material. The nanoscale materials may be biologically synthesized, such as tellurium nanorods synthesized by Bacillus selenitireducens. Composite materials of the present disclosure may have optical limiting properties and find use in optical limiting devices.

A Guide to Selecting Learning Resource Materials and Equipment.

ERIC Educational Resources Information Center

Dequin, Henry C.

The process is discussed and helpful publications are reviewed for the selection of materials in three areas--learning resource materials for library media programs, materials for special education, and equipment. In the first section, such factors as the need for suitable materials, the abundance of materials available, and financial limitations…

46 CFR 151.56-1 - Prohibited materials.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Prohibited materials. 151.56-1 Section 151.56-1 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Prohibited Materials of Construction § 151.56-1 Prohibited materials. When one of the following paragraphs of this section is referenced in table 151.05, the materials...

46 CFR 151.03-30 - Hazardous material.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Hazardous material. 151.03-30 Section 151.03-30 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Definitions § 151.03-30 Hazardous material. In this part hazardous material means a liquid material or substance that is— (a) Flammable or combustible; (b...

28 CFR 55.19 - Written materials.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Written materials. 55.19 Section 55.19... RIGHTS ACT REGARDING LANGUAGE MINORITY GROUPS Minority Language Materials and Assistance § 55.19 Written materials. (a) Types of materials. It is the obligation of the jurisdiction to decide what materials must be...

46 CFR 151.56-1 - Prohibited materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 5 2013-10-01 2013-10-01 false Prohibited materials. 151.56-1 Section 151.56-1 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Prohibited Materials of Construction § 151.56-1 Prohibited materials. When one of the following paragraphs of this section is referenced in table 151.05, the materials...

28 CFR 55.19 - Written materials.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Written materials. 55.19 Section 55.19... RIGHTS ACT REGARDING LANGUAGE MINORITY GROUPS Minority Language Materials and Assistance § 55.19 Written materials. (a) Types of materials. It is the obligation of the jurisdiction to decide what materials must be...

46 CFR 151.03-30 - Hazardous material.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 5 2012-10-01 2012-10-01 false Hazardous material. 151.03-30 Section 151.03-30 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Definitions § 151.03-30 Hazardous material. In this part hazardous material means a liquid material or substance that is— (a) Flammable or combustible; (b...

46 CFR 151.56-1 - Prohibited materials.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 5 2012-10-01 2012-10-01 false Prohibited materials. 151.56-1 Section 151.56-1 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Prohibited Materials of Construction § 151.56-1 Prohibited materials. When one of the following paragraphs of this section is referenced in table 151.05, the materials...

46 CFR 151.03-30 - Hazardous material.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 5 2013-10-01 2013-10-01 false Hazardous material. 151.03-30 Section 151.03-30 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Definitions § 151.03-30 Hazardous material. In this part hazardous material means a liquid material or substance that is— (a) Flammable or combustible; (b...

Aerogel/polymer composite materials

NASA Technical Reports Server (NTRS)

Williams, Martha K. (Inventor); Smith, Trent M. (Inventor); Fesmire, James E. (Inventor); Roberson, Luke B. (Inventor); Clayton, LaNetra M. (Inventor)

2010-01-01

The invention provides new composite materials containing aerogels blended with thermoplastic polymer materials at a weight ratio of aerogel to thermoplastic polymer of less than 20:100. The composite materials have improved thermal insulation ability. The composite materials also have better flexibility and less brittleness at low temperatures than the parent thermoplastic polymer materials.

Aerogel / Polymer Composite Materials

NASA Technical Reports Server (NTRS)

Smith, Trent M. (Inventor); Clayton, LaNetra M. (Inventor); Fesmire, James E. (Inventor); Williams, Martha K. (Inventor); Roberson, Luke B. (Inventor)

2017-01-01

The invention provides new composite materials containing aerogels blended with thermoplastic polymer materials at a weight ratio of aerogel to thermoplastic polymer of less than 20:100. The composite materials have improved thermal insulation ability. The composite materials also have better flexibility and less brittleness at low temperatures than the parent thermoplastic polymer materials.

10 CFR 74.51 - Nuclear material control and accounting for strategic special nuclear material.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 2 2012-01-01 2012-01-01 false Nuclear material control and accounting for strategic special nuclear material. 74.51 Section 74.51 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Formula Quantities of Strategic Special Nuclear...

10 CFR 74.51 - Nuclear material control and accounting for strategic special nuclear material.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Nuclear material control and accounting for strategic special nuclear material. 74.51 Section 74.51 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Formula Quantities of Strategic Special Nuclear...

10 CFR 74.51 - Nuclear material control and accounting for strategic special nuclear material.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 2 2013-01-01 2013-01-01 false Nuclear material control and accounting for strategic special nuclear material. 74.51 Section 74.51 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Formula Quantities of Strategic Special Nuclear...

10 CFR 74.51 - Nuclear material control and accounting for strategic special nuclear material.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 2 2011-01-01 2011-01-01 false Nuclear material control and accounting for strategic special nuclear material. 74.51 Section 74.51 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Formula Quantities of Strategic Special Nuclear...

10 CFR 74.51 - Nuclear material control and accounting for strategic special nuclear material.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 2 2014-01-01 2014-01-01 false Nuclear material control and accounting for strategic special nuclear material. 74.51 Section 74.51 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Formula Quantities of Strategic Special Nuclear...

Method of making nanostructured glass-ceramic waste forms

DOEpatents

Gao, Huizhen; Wang, Yifeng; Rodriguez, Mark A.; Bencoe, Denise N.

2014-07-08

A waste form for and a method of rendering hazardous materials less dangerous is disclosed that includes fixing the hazardous material in nanopores of a nanoporous material, reacting the trapped hazardous material to render it less volatile/soluble, and vitrifying the nanoporous material containing the less volatile/soluble hazardous material.

High Performance High Temperature Thermoelectric Composites with Metallic Inclusions

NASA Technical Reports Server (NTRS)

Firdosy, Samad A. (Inventor); Kaner, Richard B. (Inventor); Ma, James M. (Inventor); Fleurial, Jean-Pierre (Inventor); Star, Kurt (Inventor); Bux, Sabah K. (Inventor); Ravi, Vilupanur A. (Inventor)

2017-01-01

The present invention provides a composite thermoelectric material. The composite thermoelectric material can include a semiconductor material comprising a rare earth metal. The atomic percent of the rare earth metal in the semiconductor material can be at least about 20%. The composite thermoelectric material can further include a metal forming metallic inclusions distributed throughout the semiconductor material. The present invention also provides a method of forming this composite thermoelectric material.

Plastic Recycling Experiments in Materials Education

NASA Technical Reports Server (NTRS)

Liu, Ping; Waskom, Tommy L.

1996-01-01

The objective of this project was to introduce a series of plastic recycling experiments to students in materials-related courses such as materials science, material technology and materials testing. With the plastic recycling experiments, students not only can learn the fundamentals of plastic processing and properties as in conventional materials courses, but also can be exposed to the issue of materials life cycle and the impact on society and environment.

Material Demand Studies: Materials Sorption of Vaporized Hydrogen Peroxide

DTIC Science & Technology

2010-06-01

SORPTION OF VAPORIZED HYDROGEN PEROXIDE Lawrence R. Procell Zoe A. Hess David G. Gehring Joseph T. Lynn Philip W. Bartram Teri Lalain RESEARCH AND...2010 2. REPORT TYPE Final 3. DATES COVERED (From - To) Nov 2003 - Jul 2005 4. TITLE AND SUBTITLE Material Demand Studies: Materials Sorption of...of office surfaces 33 \\i MATERIAL DEMAND STUDIES: MATERIALS SORPTION OF VAPORIZED HYDROGEN PEROXIDE 1. BACKGROUND The Material Demand effort was

Atomic Oxygen Exposure of Power System and other Spacecraft Materials: Results of the EOIM-3 Experiment

NASA Technical Reports Server (NTRS)

Morton, Thomas L.; Ferguson, Dale C.

1997-01-01

In order to test their reactivity with Atomic Oxygen, twenty five materials were flown on the EOIM-3 (Evaluation of Oxygen Interactions with Materials) portion of the STS-46 Mission. These materials include refractory metals, candidate insulation materials, candidate radiator coatings, and a selection of miscellaneous materials. This report documents the results of the pre- and post-flight analysis of these materials.

Chemical reactor and method for chemically converting a first material into a second material

DOEpatents

Kong, Peter C.

2008-04-08

A chemical reactor and method for converting a first material into a second material is disclosed and wherein the chemical reactor is provided with a feed stream of a first material which is to be converted into a second material; and wherein the first material is combusted in the chemical reactor to produce a combustion flame, and a resulting gas; and an electrical arc is provided which is passed through or superimposed upon the combustion flame and the resulting gas to facilitate the production of the second material.

Reclaiming metallic material from an article comprising a non-metallic friable substrate

DOEpatents

Bohland, John Raphael; Anisimov, Igor Ivanovich; Dapkus, Todd James; Sasala, Richard Anthony; Smigielski, Ken Alan; Kamm, Kristin Danielle

2000-01-01

A method for reclaiming a metallic material from a article including a non-metallic friable substrate. The method comprising crushing the article into a plurality of pieces. An acidic solution capable of dissolving the metallic material is provided dissolving the metallic material in the acidic material to form an etchant effluent. The etchant effluent is separated from the friable substrate. A precipitation agent, capable of precipitating the metallic material, is added to the etchant effluent to precipitate out the metallic material from the etchant effluent. The metallic material is then recovered.

Free-standing oxide superconducting articles

DOEpatents

Wu, X.D.; Muenchausen, R.E.

1993-12-14

A substrate-free, free-standing epitaxially oriented superconductive film including a layer of a template material and a layer of a ceramic superconducting material is provided together with a method of making such a substrate-free ceramic superconductive film by coating an etchable material with a template layer, coating the template layer with a layer of a ceramic superconductive material, coating the layer of ceramic superconductive material with a protective material, removing the etchable material by an appropriate means so that the etchable material is separated from a composite structure including the template layer.

Electroless atomic layer deposition

DOEpatents

Robinson, David Bruce; Cappillino, Patrick J.; Sheridan, Leah B.; Stickney, John L.; Benson, David M.

2017-10-31

A method of electroless atomic layer deposition is described. The method electrolessly generates a layer of sacrificial material on a surface of a first material. The method adds doses of a solution of a second material to the substrate. The method performs a galvanic exchange reaction to oxidize away the layer of the sacrificial material and deposit a layer of the second material on the surface of the first material. The method can be repeated for a plurality of iterations in order to deposit a desired thickness of the second material on the surface of the first material.

Chemical reactor for converting a first material into a second material

DOEpatents

Kong, Peter C

2012-10-16

A chemical reactor and method for converting a first material into a second material is disclosed and wherein the chemical reactor is provided with a feed stream of a first material which is to be converted into a second material; and wherein the first material is combusted in the chemical reactor to produce a combustion flame, and a resulting gas; and an electrical arc is provided which is passed through or superimposed upon the combustion flame and the resulting gas to facilitate the production of the second material.

Materials, critical materials and clean-energy technologies

NASA Astrophysics Data System (ADS)

Eggert, R.

2017-07-01

Modern engineered materials, components and systems depend on raw materials whose properties provide essential functionality to these technologies. Some of these raw materials are subject to supply-chain risks, and such materials are known as critical materials. This paper reviews corporate, national and world perspectives on material criticality. It then narrows its focus to studies that assess "what is critical" to clean-energy technologies. The focus on supply-chain risks is not meant to be alarmist but rather to encourage attention to monitoring these risks and pursuing technological innovation to mitigate the risks.

Nuclear reactor for breeding U.sup.233

DOEpatents

Bohanan, Charles S.; Jones, David H.; Raab, Jr., Harry F.; Radkowsky, Alvin

1976-01-01

A light-water-cooled nuclear reactor capable of breeding U.sup.233 for use in a light-water breeder reactor includes physically separated regions containing U.sup.235 fissile material and U.sup.238 fertile material and Th.sup.232 fertile material and Pu.sup.239 fissile material, if available. Preferably the U.sup.235 fissile material and U.sup.238 fertile material are contained in longitudinally movable seed regions and the Pu.sup.239 fissile material and Th.sup.232 fertile material are contained in blanket regions surrounding the seed regions.

Materials technology assessment for a 1050 K Stirling space engine design

NASA Technical Reports Server (NTRS)

Scheuermann, Coulson M.; Dreshfield, Robert L.; Gaydosh, Darrell J.; Kiser, James D.; Mackay, Rebecca A.; Mcdaniels, David L.; Petrasek, Donald W.; Vannucci, Raymond D.; Bowles, Kenneth J.; Watson, Gordon K.

1988-01-01

An assessment of materials technology and proposed materials selection was made for the 1050 K (superalloy) Stirling Space Engine design. The objectives of this assessment were to evaluate previously proposed materials selections, evaluate the current state-of-the-art materials, propose potential alternate materials selections and identify research and development efforts needed to provide materials that can meet the stringent system requirements. This assessment generally reaffirmed the choices made by the contractor. However, in many cases alternative choices were described and suggestions for needed materials and fabrication research and development were made.

Method for distributing chemicals through a fibrous material using low-headspace dielectric heating

DOEpatents

Banerjee, Sujit; Malcolm, Earl

2002-01-01

System and method for diffusing chemicals rapidly and evenly into and through fibrous material, such as wood. Chemicals are introduced into the fibrous material by applying the chemicals to the fibrous material. After treating the fibrous material with the chemicals, the fibrous material is maintained under low-headspace conditions. Thermal energy or dielectric heating, such as microwave or radio frequency energy, is applied to the fibrous material. As a result, the chemicals are able to distribute evenly and quickly throughout the fibrous material.

Fracture/Severance of Materials

NASA Technical Reports Server (NTRS)

Schimmel, Morry L. (Inventor); Bement, Laurence J. (Inventor); DuBrucq, Glenn F., Jr. (Inventor); Klein, Edward A. (Inventor)

1998-01-01

A method for severing or weakening materials is discussed. Explosive cords are placed in grooves on the upper surface of the material to be severed or weakened. The explosive cords are initiated simultaneously to introduce explosive shock waves into the material. These shock waves progress toward the centerline between the explosive cords and the lower surface of the material. Intersecting and reflected waves produce a rarefaction zone on the centerline to fail the material in tension. A groove may also be cut in the lower surface of the material to aid in severing or weakening the material.

Biological issues in materials science and engineering: Interdisciplinarity and the bio-materials paradigm

NASA Astrophysics Data System (ADS)

Murr, L. E.

2006-07-01

Biological systems and processes have had, and continue to have, important implications and applications in materials extraction, processing, and performance. This paper illustrates some interdisciplinary, biological issues in materials science and engineering. These include metal extraction involving bacterial catalysis, galvanic couples, bacterial-assisted corrosion and degradation of materials, biosorption and bioremediation of toxic and other heavy metals, metal and material implants and prostheses and related dental and medical biomaterials developments and applications, nanomaterials health benefits and toxicity issue, and biomimetics and biologically inspired materials developments. These and other examples provide compelling evidence and arguments for emphasizing biological sicences in materials science and engineering curricula and the implementation of a bio-materials paradigm to facilitate the emergence of innovative interdisciplinarity involving the biological sciences and materials sciences and engineering.

Application of materials database (MAT.DB.) to materials education

NASA Technical Reports Server (NTRS)

Liu, Ping; Waskom, Tommy L.

1994-01-01

Finding the right material for the job is an important aspect of engineering. Sometimes the choice is as fundamental as selecting between steel and aluminum. Other times, the choice may be between different compositions in an alloy. Discovering and compiling materials data is a demanding task, but it leads to accurate models for analysis and successful materials application. Mat. DB. is a database management system designed for maintaining information on the properties and processing of engineered materials, including metals, plastics, composites, and ceramics. It was developed by the Center for Materials Data of American Society for Metals (ASM) International. The ASM Center for Materials Data collects and reviews material property data for publication in books, reports, and electronic database. Mat. DB was developed to aid the data management and material applications.

Materials Frontiers to Empower Quantum Computing

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

Taylor, Antoinette Jane; Sarrao, John Louis; Richardson, Christopher

This is an exciting time at the nexus of quantum computing and materials research. The materials frontiers described in this report represent a significant advance in electronic materials and our understanding of the interactions between the local material and a manufactured quantum state. Simultaneously, directed efforts to solve materials issues related to quantum computing provide an opportunity to control and probe the fundamental arrangement of matter that will impact all electronic materials. An opportunity exists to extend our understanding of materials functionality from electronic-grade to quantum-grade by achieving a predictive understanding of noise and decoherence in qubits and their originsmore » in materials defects and environmental coupling. Realizing this vision systematically and predictively will be transformative for quantum computing and will represent a qualitative step forward in materials prediction and control.« less

Advanced numerical models and material characterisation techniques for composite materials subject to impact and shock wave loading

NASA Astrophysics Data System (ADS)

Clegg, R. A.; White, D. M.; Hayhurst, C.; Ridel, W.; Harwick, W.; Hiermaier, S.

2003-09-01

The development and validation of an advanced material model for orthotropic materials, such as fibre reinforced composites, is described. The model is specifically designed to facilitate the numerical simulation of impact and shock wave propagation through orthotropic materials and the prediction of subsequent material damage. Initial development of the model concentrated on correctly representing shock wave propagation in composite materials under high and hypervelocity impact conditions [1]. This work has now been extended to further concentrate on the development of improved numerical models and material characterisation techniques for the prediction of damage, including residual strength, in fibre reinforced composite materials. The work is focussed on Kevlar-epoxy however materials such as CFRP are also being considered. The paper describes our most recent activities in relation to the implementation of advanced material modelling options in this area. These enable refined non-liner directional characteristics of composite materials to be modelled, in addition to the correct thermodynamic response under shock wave loading. The numerical work is backed by an extensive experimental programme covering a wide range of static and dynamic tests to facilitate derivation of model input data and to validate the predicted material response. Finally, the capability of the developing composite material model is discussed in relation to a hypervelocity impact problem.

Near single-crystalline, high-carrier-mobility silicon thin film on a polycrystalline/amorphous substrate

DOEpatents

Findikoglu, Alp T [Los Alamos, NM; Jia, Quanxi [Los Alamos, NM; Arendt, Paul N [Los Alamos, NM; Matias, Vladimir [Santa Fe, NM; Choi, Woong [Los Alamos, NM

2009-10-27

A template article including a base substrate including: (i) a base material selected from the group consisting of polycrystalline substrates and amorphous substrates, and (ii) at least one layer of a differing material upon the surface of the base material; and, a buffer material layer upon the base substrate, the buffer material layer characterized by: (a) low chemical reactivity with the base substrate, (b) stability at temperatures up to at least about 800.degree. C. under low vacuum conditions, and (c) a lattice crystal structure adapted for subsequent deposition of a semiconductor material; is provided, together with a semiconductor article including a base substrate including: (i) a base material selected from the group consisting of polycrystalline substrates and amorphous substrates, and (ii) at least one layer of a differing material upon the surface of the base material; and, a buffer material layer upon the base substrate, the buffer material layer characterized by: (a) low chemical reactivity with the base substrate, (b) stability at temperatures up to at least about 800.degree. C. under low vacuum conditions, and (c) a lattice crystal structure adapted for subsequent deposition of a semiconductor material, and, a top-layer of semiconductor material upon the buffer material layer.

3D Viscoelastic Traction Force Microscopy

PubMed Central

Toyjanova, Jennet; Hannen, Erin; Bar-Kochba, Eyal; Darling, Eric M.; Henann, David L.; Franck, Christian

2014-01-01

Native cell-material interactions occur on materials differing in their structural composition, chemistry, and physical compliance. While the last two decades have shown the importance of traction forces during cell-material interactions, they have been almost exclusively presented on purely elastic in-vitro materials. Yet, most bodily tissue materials exhibit some level of viscoelasticity, which could play an important role in how cells sense and transduce tractions. To expand the realm of cell traction measurements and to encompass all materials from elastic to viscoelastic, this paper presents a general, and comprehensive approach for quantifying 3D cell tractions in viscoelastic materials. This methodology includes the experimental characterization of the time-dependent material properties for any viscoelastic material with the subsequent mathematical implementation of the determined material model into a 3D traction force microscopy (3D TFM) framework. Utilizing this new 3D viscoelastic TFM (3D VTFM) approach, we quantify the influence of viscosity on the overall material traction calculations and quantify the error associated with omitting time-dependent material effects, as is the case for all other TFM formulations. We anticipate that the 3D VTFM technique will open up new avenues of cell-material investigations on even more physiologically relevant time-dependent materials including collagen and fibrin gels. PMID:25170569

Preparation of calibration materials for microanalysis of Ti minerals by direct fusion of synthetic and natural materials: experience with LA-ICP-MS analysis of some important minor and trace elements in ilmenite and rutile.

PubMed

Odegård, M; Mansfeld, J; Dundas, S H

2001-08-01

Calibration materials for microanalysis of Ti minerals have been prepared by direct fusion of synthetic and natural materials by resistance heating in high-purity graphite electrodes. Synthetic materials were FeTiO3 and TiO2 reagents doped with minor and trace elements; CRMs for ilmenite, rutile, and a Ti-rich magnetite were used as natural materials. Problems occurred during fusion of Fe2O3-rich materials, because at atmospheric pressure Fe2O3 decomposes into Fe3O4 and O2 at 1462 degrees C. An alternative fusion technique under pressure was tested, but the resulting materials were characterized by extensive segregation and development of separate phases. Fe2O3-rich materials were therefore fused below this temperature, resulting in a form of sintering, without conversion of the materials into amorphous glasses. The fused materials were studied by optical microscopy and EPMA, and tested as calibration materials by inductively coupled plasma mass spectrometry, equipped with laser ablation for sample introduction (LA-ICP-MS). It was demonstrated that calibration curves based on materials of rutile composition, within normal analytical uncertainty, generally coincide with calibration curves based on materials of ilmenite composition. It is, therefore, concluded that LA-ICP-MS analysis of Ti minerals can with advantage be based exclusively on calibration materials prepared for rutile, thereby avoiding the special fusion problems related to oxide mixtures of ilmenite composition. It is documented that sintered materials were in good overall agreement with homogeneous glass materials, an observation that indicates that in other situations also sintered mineral concentrates might be a useful alternative for instrument calibration, e.g. as alternative to pressed powders.

Compaction of Confining Materials in Pillar Blast Tests

NASA Astrophysics Data System (ADS)

Petropoulos, N.; Wimmer, M.; Johansson, D.; Nordlund, E.

2018-06-01

Two confined pillar tests were conducted at the Kiirunavaara mine to investigate the degree of compaction of three materials, i.e., 0-32-mm backfilled material, a blend of ore and waste material and caved material. Two blastholes were drilled parallel to each pillar wall, and several measurement holes were drilled in between the blastholes through each pillar. Both the measurement holes and backfilled materials, except the caved material, were instrumented. Two types of measurements were taken: dynamic measurements with accelerometers, and static measurements which considered the location of the instrumentation pre- and post-blast. Dynamic measurements involved the burden movement and the confining material behavior, and static measurements contained the final location of sensors inside and the angle of repose of the confining material. The results showed that the size distribution of the confining material affects its behavior under dynamic loading. The backfilled materials showed an apparent cohesion forming an agglomeration on the surface of the blasted burden. The burden moved as one slab due to simultaneous detonation. A gap was formed between the blasted burden and the new face. This gap was partially filled with burden erosion material which was finer fragmented than the blasted burden material.

Permeability analysis of Asbuton material used as core layers of water resistance in the body of dam

NASA Astrophysics Data System (ADS)

Rahim, H.; Tjaronge, M. W.; Thaha, A.; Djamaluddin, R.

2017-11-01

In order to increase consumption of the local materials and national products, large reserves of Asbuton material about 662.960 million tons in the Buton Islands became an alternative as a waterproof core layer in the body of dam. The Asbuton material was used in this research is Lawele Granular Asphalt (LGA). This study was an experimental study conducted in the laboratory by conducting density testing (content weight) and permeability on Asbuton material. Testing of the Asbuton material used Falling Head method to find out the permeability value of Asbuton material. The data of test result to be analyzed are the relation between compaction energy and density value also relation between density value and permeability value of Asbuton material. The result shows that increases the number of blow apply to the Asbuton material at each layer will increase the density of the Asbuton material. The density value of Asbuton material that satisfies the requirements for use as an impermeable core layer in the dam body is 1.53 grams/cm3. The increase the density value (the weight of the contents) of the Asbuton material will reduce its permeability value of the Asbuton material.

Apparatus and Method for Increasing the Diameter of Metal Alloy Wires Within a Molten Metal Pool

DOEpatents

Hartman, Alan D.; Argetsinger, Edward R.; Hansen, Jeffrey S.; Paige, Jack I.; King, Paul E.; Turner, Paul C.

2002-01-29

In a dip forming process the core material to be coated is introduced directly into a source block of coating material eliminating the need for a bushing entrance component. The process containment vessel or crucible is heated so that only a portion of the coating material becomes molten, leaving a solid portion of material as the entrance port of, and seal around, the core material. The crucible can contain molten and solid metals and is especially useful when coating core material with reactive metals. The source block of coating material has been machined to include a close tolerance hole of a size and shape to closely fit the core material. The core material moves first through the solid portion of the source block of coating material where the close tolerance hole has been machined, then through a solid/molten interface, and finally through the molten phase where the diameter of the core material is increased. The crucible may or may not require water-cooling depending upon the type of material used in crucible construction. The system may operate under vacuum, partial vacuum, atmospheric pressure, or positive pressure depending upon the type of source material being used.

Metal-organic frameworks and their derived materials for electrochemical energy storage and conversion: Promises and challenges.

PubMed

Wu, Hao Bin; Lou, Xiong Wen David

2017-12-01

In addition to their conventional uses, metal-organic frameworks (MOFs) have recently emerged as an interesting class of functional materials and precursors of inorganic materials for electrochemical energy storage and conversion technologies. This class of MOF-related materials can be broadly categorized into two groups: pristine MOF-based materials and MOF-derived functional materials. Although the diversity in composition and structure leads to diverse and tunable functionalities of MOF-based materials, it appears that much more effort in this emerging field is devoted to synthesizing MOF-derived materials for electrochemical applications. This is in view of two main drawbacks of MOF-based materials: the low conductivity nature and the stability issue. On the contrary, MOF-derived synthesis strategies have substantial advantages in controlling the composition and structure of MOF-derived materials. From this perspective, we review some emerging applications of both groups of MOF-related materials as electrode materials for rechargeable batteries and electrochemical capacitors, efficient electrocatalysts, and even electrolytes for electrochemical devices. By highlighting the advantages and challenges of each class of materials for different applications, we hope to shed some light on the future development of this highly exciting area.

A new classification system for all-ceramic and ceramic-like restorative materials.

PubMed

Gracis, Stefano; Thompson, Van P; Ferencz, Jonathan L; Silva, Nelson R F A; Bonfante, Estevam A

2015-01-01

Classification systems for all-ceramic materials are useful for communication and educational purposes and warrant continuous revisions and updates to incorporate new materials. This article proposes a classification system for ceramic and ceramic-like restorative materials in an attempt to systematize and include a new class of materials. This new classification system categorizes ceramic restorative materials into three families: (1) glass-matrix ceramics, (2) polycrystalline ceramics, and (3) resin-matrix ceramics. Subfamilies are described in each group along with their composition, allowing for newly developed materials to be placed into the already existing main families. The criteria used to differentiate ceramic materials are based on the phase or phases present in their chemical composition. Thus, an all-ceramic material is classified according to whether a glass-matrix phase is present (glass-matrix ceramics) or absent (polycrystalline ceramics) or whether the material contains an organic matrix highly filled with ceramic particles (resin-matrix ceramics). Also presented are the manufacturers' clinical indications for the different materials and an overview of the different fabrication methods and whether they are used as framework materials or monolithic solutions. Current developments in ceramic materials not yet available to the dental market are discussed.

Metal-organic frameworks and their derived materials for electrochemical energy storage and conversion: Promises and challenges

PubMed Central

Wu, Hao Bin; Lou, Xiong Wen (David)

2017-01-01

In addition to their conventional uses, metal-organic frameworks (MOFs) have recently emerged as an interesting class of functional materials and precursors of inorganic materials for electrochemical energy storage and conversion technologies. This class of MOF-related materials can be broadly categorized into two groups: pristine MOF-based materials and MOF-derived functional materials. Although the diversity in composition and structure leads to diverse and tunable functionalities of MOF-based materials, it appears that much more effort in this emerging field is devoted to synthesizing MOF-derived materials for electrochemical applications. This is in view of two main drawbacks of MOF-based materials: the low conductivity nature and the stability issue. On the contrary, MOF-derived synthesis strategies have substantial advantages in controlling the composition and structure of MOF-derived materials. From this perspective, we review some emerging applications of both groups of MOF-related materials as electrode materials for rechargeable batteries and electrochemical capacitors, efficient electrocatalysts, and even electrolytes for electrochemical devices. By highlighting the advantages and challenges of each class of materials for different applications, we hope to shed some light on the future development of this highly exciting area. PMID:29214220

Apparatus and method for increasing the diameter of metal alloy wires within a molten metal pool

DOEpatents

Hartman, Alan D.; Argetsinger, Edward R.; Hansen, Jeffrey S.; Paige, Jack I.; King, Paul E.; Turner, Paul C.

2002-01-29

In a dip forming process the core material to be coated is introduced directly into a source block of coating material eliminating the need for a bushing entrance component. The process containment vessel or crucible is heated so that only a portion of the coating material becomes molten, leaving a solid portion of material as the entrance port of, and seal around, the core material. The crucible can contain molten and solid metals and is especially useful when coating core material with reactive metals. The source block of coating material has been machined to include a close tolerance hole of a size and shape to closely fit the core material. The core material moves first through the solid portion of the source block of coating material where the close tolerance hole has been machined, then through a solid/molten interface, and finally through the molten phase where the diameter of the core material is increased. The crucible may or may not require water-cooling depending upon the type of material used in crucible construction. The system may operate under vacuum, partial vacuum, atmospheric pressure, or positive pressure depending upon the type of source material being used.

Behavioural response of Phytoseiulus persimilisin inert materials for technical application.

PubMed

Wendorf, Dennis; Sermann, Helga; Katz, Peter; Lerche, Sandra; Büttner, Carmen

2009-01-01

A large scale application of the predatory mite Phytoseiulus persimilis Athias-Henriot for use in the biological control of spider mites in the field requires testing the behaviour of Phytoseiulus persimilis in inert materials, like millet pelts and Vermiculite (1-3 mm). In laboratory studies, the distribution of the individuals in such materials, the time of remaining in the material were proved. To examine the abiotic influences on the time of remaining in the material, the dampness of the materials was varied (0%, 5% and 10%). Moreover, the influence of attitude of materials was tested. The time of emigration from the material was noted for each individual. Emigration from all dry materials was completed 15 minutes at the latest after set up of the mites. The increase of dampness had an obvious effect on the time of remaining in the material. In this respect the material millet pelts showed the most favourable effect with 10% dampness. Increasing attitude of material the mobility of predatory mites will be influenced negatively above 75 cm. Up to 50 cm, mites have not a problem to move in the material and the time of remaining can be prolonged considerably.

Computational prediction of new auxetic materials.

PubMed

Dagdelen, John; Montoya, Joseph; de Jong, Maarten; Persson, Kristin

2017-08-22

Auxetics comprise a rare family of materials that manifest negative Poisson's ratio, which causes an expansion instead of contraction under tension. Most known homogeneously auxetic materials are porous foams or artificial macrostructures and there are few examples of inorganic materials that exhibit this behavior as polycrystalline solids. It is now possible to accelerate the discovery of materials with target properties, such as auxetics, using high-throughput computations, open databases, and efficient search algorithms. Candidates exhibiting features correlating with auxetic behavior were chosen from the set of more than 67 000 materials in the Materials Project database. Poisson's ratios were derived from the calculated elastic tensor of each material in this reduced set of compounds. We report that this strategy results in the prediction of three previously unidentified homogeneously auxetic materials as well as a number of compounds with a near-zero homogeneous Poisson's ratio, which are here denoted "anepirretic materials".There are very few inorganic materials with auxetic homogenous Poisson's ratio in polycrystalline form. Here authors develop an approach to screening materials databases for target properties such as negative Poisson's ratio by using stability and structural motifs to predict new instances of homogenous auxetic behavior as well as a number of materials with near-zero Poisson's ratio.

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

Seo, Dong-Kyun; Medpelli, Dinesh; Ladd, Danielle

A product formed from a first material including a geopolymer resin material, a geopolymer resin, or a combination thereof by contacting the first material with a fluid and removing at least some of the fluid to yield a product. The first material may be formed by heating and/or aging an initial geopolymer resin material to yield the first material before contacting the first material with the fluid. In some cases, contacting the first material with the fluid breaks up or disintegrates the first material (e.g., in response to contact with the fluid and in the absence of external mechanical stress),more » thereby forming particles having an external dimension in a range between 1 nm and 2 cm.« less

Renewable smart materials

NASA Astrophysics Data System (ADS)

Kim, Hyun Chan; Mun, Seongcheol; Ko, Hyun-U.; Zhai, Lindong; Kafy, Abdullahil; Kim, Jaehwan

2016-07-01

The use of renewable materials is essential in future technologies to harmonize with our living environment. Renewable materials can maintain our resources from the environment so as to overcome degradation of natural environmental services and diminished productivity. This paper reviews recent advancement of renewable materials for smart material applications, including wood, cellulose, chitin, lignin, and their sensors, actuators and energy storage applications. To further improve functionality of renewable materials, hybrid composites of inorganic functional materials are introduced by incorporating carbon nanotubes, titanium dioxide and tin oxide conducting polymers and ionic liquids. Since renewable materials have many advantages of biocompatible, sustainable, biodegradable, high mechanical strength and versatile modification behaviors, more research efforts need to be focused on the development of renewable smart materials.

Microfabrication of hierarchical structures for engineered mechanical materials

NASA Astrophysics Data System (ADS)

Vera Canudas, Marc

Materials found in nature present, in some cases, unique properties from their constituents that are of great interest in engineered materials for applications ranging from structural materials for the construction of bridges, canals and buildings to the fabrication of new lightweight composites for airplane and automotive bodies, to protective thin film coatings, amongst other fields. Research in the growing field of biomimetic materials indicates that the micro-architectures present in natural materials are critical to their macroscopic mechanical properties. A better understanding of the effect that structure and hierarchy across scales have on the material properties will enable engineered materials with enhanced properties. At the moment, very few theoretical models predict mechanical properties of simple materials based on their microstructures. Moreover these models are based on observations from complex biological systems. One way to overcome this challenge is through the use of microfabrication techniques to design and fabricate simple materials, more appropriate for the study of hierarchical organizations and microstructured materials. Arrays of structures with controlled geometry and dimension can be designed and fabricated at different length scales, ranging from a few hundred nanometers to centimeters, in order to mimic similar systems found in nature. In this thesis, materials have been fabricated in order to gain fundamental insight into the complex hierarchical materials found in nature and to engineer novel materials with enhanced mechanical properties. The materials fabricated here were mechanically characterized and compared to simple mechanics models to describe their behavior with the goal of applying the knowledge acquired to the design and synthesis of future engineered materials with novel properties.

Comparison of wear between occlusal splint materials and resin composite materials.

PubMed

Reyes-Sevilla, M; Kuijs, R H; Werner, A; Kleverlaan, C J; Lobbezoo, F

2018-07-01

Tooth wear in bruxing patients often results in a need for treatment with composite restorations. In some cases, bruxing patients receive an occlusal splint as a protective means as well. However, the wear between these opposing materials has not been investigated yet. The aim of this in vitro study was to assess the wear of different splint materials against resin composite materials. A two-body wear test was conducted using the ACTA wear machine. The materials selected for this study were three composites used for direct restorations (Filtek Z250, CLEARFIL AP-X, and Filtek Supreme XT) and four occlusal splints materials, viz. a polyamide resin (ThermoSens) an conventional (hand-processed), milled and printed polymethylmethacrylate (PMMA). As antagonistic materials, stainless steel, Filtek Supreme XT and CLEARFIL AP-X were used. The wear rate of the seven materials was determined after 200 000 cycles, using a profilometry. The rates were analysed using two-way ANOVA and post hoc Tukey's tests. The wear rates were significantly higher for the conventional and milled PMMA materials than for all other materials (P < .001). The wear rates of printed PMMA and the polyamide resin were comparable to composite wear rates. The antagonist materials have minor or no influence on the amount of wear of the various splint materials (P < .001). In conclusion, different splint materials yielded different wear rates for all antagonist materials tested. Keeping in mind that this study is an experimental in vitro study, this finding enables practitioners to choose the splint material necessary according to their patients' needs. © 2018 John Wiley & Sons Ltd.

Materials in the economy; material flows, scarcity, and the environment

USGS Publications Warehouse

Wagner, Lorie A.

2002-01-01

The importance of materials to the economy of the United States is described, including the levels of consumption and uses of materials. The paths (or flows) that materials take from extraction, through processing, to consumer products, and then final disposition are illustrated. Scarcity and environmental issues as they relate to the flow of materials are discussed. Examples for the three main themes of the report (material flows, scarcity, and the environment) are presented.

Low transient thermal stress turbine engine components

DOEpatents

Shi, Jun [Glastonbury, CT; Schmidt, Wayde R [Pomfret Center, CT

2011-06-28

A turbine vane includes a platform; and at least one airfoil mounted to the platform and having a trailing edge and a leading edge, wherein the vane is composed of a functionally graded material having a first material and a second material, wherein the trailing edge includes a greater amount of the first material than the second material, and the leading edge includes a greater amount of the second material than the first material.

Coaxial test fixture

DOEpatents

Praeg, W.F.

1984-03-30

This invention pertains to arrangements for performing electrical tests on contact material samples, and in particular for testing contact material test samples in an evacuated environment under high current loads. Frequently, it is desirable in developing high-current separable contact material, to have at least a preliminary analysis of selected candidate conductor materials. Testing of material samples will hopefully identify materials unsuitable for high current electrical contact without requiring incorporation of the materials into a completed and oftentimes complex structure.

Thermoelectric materials and methods for synthesis thereof

DOEpatents

Ren, Zhifeng; Zhang, Qinyong; Zhang, Qian; Chen, Gang

2015-08-04

Materials having improved thermoelectric properties are disclosed. In some embodiments, lead telluride/selenide based materials with improved figure of merit and mechanical properties are disclosed. In some embodiments, the lead telluride/selenide based materials of the present disclosure are p-type thermoelectric materials formed by adding sodium (Na), silicon (Si) or both to thallium doped lead telluride materials. In some embodiments, the lead telluride/selenide based materials are formed by doping lead telluride/selenides with potassium.

Nanocrystalline ceramic materials

DOEpatents

Siegel, Richard W.; Nieman, G. William; Weertman, Julia R.

1994-01-01

A method for preparing a treated nanocrystalline metallic material. The method of preparation includes providing a starting nanocrystalline metallic material with a grain size less than about 35 nm, compacting the starting nanocrystalline metallic material in an inert atmosphere and annealing the compacted metallic material at a temperature less than about one-half the melting point of the metallic material.

46 CFR 151.58-1 - Required materials.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Required materials. 151.58-1 Section 151.58-1 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Required Materials of Construction § 151.58-1 Required materials... materials listed in that paragraph may be used in components that contact the cargo or its vapor: (a...

46 CFR 151.58-1 - Required materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 5 2013-10-01 2013-10-01 false Required materials. 151.58-1 Section 151.58-1 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Required Materials of Construction § 151.58-1 Required materials... materials listed in that paragraph may be used in components that contact the cargo or its vapor: (a...

46 CFR 151.58-1 - Required materials.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 5 2012-10-01 2012-10-01 false Required materials. 151.58-1 Section 151.58-1 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Required Materials of Construction § 151.58-1 Required materials... materials listed in that paragraph may be used in components that contact the cargo or its vapor: (a...

Obtaining NASA Approval for use of Non-Metallic Materials in Manned Space Flight

NASA Technical Reports Server (NTRS)

Davis, Samuel E.; Wise, Harry L.

2003-01-01

Material manufacturers and suppliers are often surprised when a material commonly provided to industry is not approved for use on manned spacecraft. Often the reason is a lack of test data in environments that simulate those encountered in space applications, especially oxygen-enriched conditions, which significantly increase both the likelihood of material combustion and the propagation of a fire. This paper introduces the requirements for flight approval of non-metallic materials, focusing on material testing for human-rated space flight programs; it reviews the history of flight materials requirements and provides the rationale for such and introduces specific requirements related to testing and to good material engineering and design practices. After describing the procedure for submitting materials to be tested, the paper outlines options available if a material fails testing. In addition, this treatise introduces the National Aeronautics and Space Administration's (NASA's) Materials and Processes Technical Information System (MAPTIS), a database housing all test data produced in accordance with NASA-STD-6001, Flammability, Odor, Offgassing, and Compatibility Requirements and Test Procedures for Materials in Environments that Support Combustion.

Energy Conversion Alternatives Study (ECAS), Westinghouse phase 1. Volume 2: Materials considerations. [materials used in boilers and heat exchangers of energy conversion systems for electric power plants using coal

NASA Technical Reports Server (NTRS)

Thomas, D. E.

1976-01-01

Extensive studies are presented which were carried out on materials behavior in nine advanced energy conversion systems employing coal and coal-derived fuels. The areas of materials behavior receiving particular attention in this regard are: (1) fireside corrosion and erosion in boiler and heat exchanger materials, (2) oxidation and hot corrosion of gas turbine materials, (3) liquid metal corrosion and mass transport, (4) high temperature steam corrosion, (5) compatability of materials with coal slag and MHD seed, (6) reaction of materials with impure helium, (7) allowable stresses for boiler and heat exchanger materials, (8) environmental effects on mechanical properties, and (9) liquid metal purity control and instrumentation. Such information was then utilized in recommending materials for use in the critical components of the power systems, and at the same time to identify materials problem areas and to evaluate qualitatively the difficulty of solving those problems. Specific materials recommendations for critical components of the nine advanced systems under study are contained in summary tables.

Method of Fabricating Protective Coating for a Crucible with the Coating Having Channels Formed Therein

NASA Technical Reports Server (NTRS)

Grugel, Richard N. (Inventor)

2004-01-01

A method is provided for the fabrication of a protective coating for a crucible with channels being formed in the coating. A material is adhered to the outer wall of the crucible to form a pattern thereon. The outer wall of the crucible along with the pattern of material adhered thereto is next coated with another material. The material used to form the pattern should extend through the outer material coating to define at least one port therein. Next, the crucible with its pattern of material and outer coating material is heated to a temperature of transformation at which the pattern of material is transformed to a fluidic state while the crucible and outer coating material maintain their solid integrity. Such transformation could also be accomplished by using a solvent that causes the pattern of material to dissolve. Finally, the material in its fluidic state is removed via the at least one port formed in the outer material coating thereby leaving channels defined in the coating adjacent the outer wall of the crucible.

The Next Generation Thermoelectric Materials

NASA Astrophysics Data System (ADS)

Tritt, Terry M.

1999-11-01

Recently there been renewed interest in materials for thermoelectric refrigeration and power generation applications.^1, 2 Many new materials and new classes of materials are being investigated for potential thermoelectric applications. An introduction to thermoelectric refrigeration and power generation, the advantages and disadvantages and potential applications will be discussed. An overview of some of the current thermoelectric materials under investigation and the criteria for selection of new materials will be given. To be promising as a thermoelectric material, a material must have a high Seebeck coefficient, α, high electrical conductivity, σ, and a low thermal conductivity, λ. These parameters go into the material's dimensionless figure of merit ZT = α ^2σT/λ. Our research at Clemson is focused on a number of new materials, quasicrystals and pentatelluride materials, which show promise for thermoelectrics and these systems will be briefly discussed. Demonstrations of thermoelectric devices will be shown and discussed. 1.) Thermoelectric Materials: New Directions and Approaches, MRS Volumes 478 and 545, edited by Terry M. Tritt et. al. 2.) G. Mahan, B. Sales and J. Sharp, Physics Today, March 50, 42, 1997

Thermal effects on transducer material for heat assisted magnetic recording application

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

Ji, Rong, E-mail: Ji-Rong@dsi.a-star.edu.sg; Xu, Baoxi; Cen, Zhanhong

2015-05-07

Heat Assisted Magnetic Recording (HAMR) is a promising technology for next generation hard disk drives with significantly increased data recording capacities. In HAMR, an optical near-field transducer (NFT) is used to concentrate laser energy on a magnetic recording medium to fulfill the heat assist function. The key components of a NFT are transducer material, cladding material, and adhesion material between the cladding and the transducer materials. Since transducer materials and cladding materials have been widely reported, this paper focuses on the adhesion materials between the Au transducer and the Al{sub 2}O{sub 3} cladding material. A comparative study for two kindsmore » of adhesion material, Ta and Cr, has been conducted. We found that Ta provides better thermal stability to the whole transducer than Cr. This is because after thermal annealing, chromium forms oxide material at interfaces and chromium atoms diffuse remarkably into the Au layer and react with Au to form Au alloy. This study also provides insights on the selection of adhesion material for HAMR transducer.« less

A multifluid model extended for strong temperature nonequilibrium

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

Chang, Chong

2016-08-08

We present a multifluid model in which the material temperature is strongly affected by the degree of segregation of each material. In order to track temperatures of segregated form and mixed form of the same material, they are defined as different materials with their own energy. This extension makes it necessary to extend multifluid models to the case in which each form is defined as a separate material. Statistical variations associated with the morphology of the mixture have to be simplified. Simplifications introduced include combining all molecularly mixed species into a single composite material, which is treated as another segregatedmore » material. Relative motion within the composite material, diffusion, is represented by material velocity of each component in the composite material. Compression work, momentum and energy exchange, virtual mass forces, and dissipation of the unresolved kinetic energy have been generalized to the heterogeneous mixture in temperature nonequilibrium. The present model can be further simplified by combining all mixed forms of materials into a composite material. Molecular diffusion in this case is modeled by the Stefan-Maxwell equations.« less

Joining of dissimilar materials

DOEpatents

Tucker, Michael C; Lau, Grace Y; Jacobson, Craig P

2012-10-16

A method of joining dissimilar materials having different ductility, involves two principal steps: Decoration of the more ductile material's surface with particles of a less ductile material to produce a composite; and, sinter-bonding the composite produced to a joining member of a less ductile material. The joining method is suitable for joining dissimilar materials that are chemically inert towards each other (e.g., metal and ceramic), while resulting in a strong bond with a sharp interface between the two materials. The joining materials may differ greatly in form or particle size. The method is applicable to various types of materials including ceramic, metal, glass, glass-ceramic, polymer, cermet, semiconductor, etc., and the materials can be in various geometrical forms, such as powders, fibers, or bulk bodies (foil, wire, plate, etc.). Composites and devices with a decorated/sintered interface are also provided.

Insulation Materials Comprising Fibers Having a Partially Cured Polymer Coating Thereon, Articles Including Such Insulation Materials, and Methods of Forming Such Materials and Articles

NASA Technical Reports Server (NTRS)

Morgan, Richard E. (Inventor); Meeks, Craig L. (Inventor)

2017-01-01

Insulation materials have a coating of a partially cured polymer on a plurality of fibers, and the plurality of coated fibers in a cross-linked polymeric matrix. Insulation may be formed by applying a preceramic polymer to a plurality of fibers, heating the preceramic polymer to form a partially cured polymer over at least portions of the plurality of fibers, disposing the plurality of fibers in a polymeric material, and curing the polymeric material. A rocket motor may be formed by disposing a plurality of coated fibers in an insulation precursor, curing the insulation precursor to form an insulation material without sintering the partially cured polymer, and providing an energetic material over the polymeric material. An article includes an insulation material over at least one surface.

Superconducting thermoelectric generator

DOEpatents

Metzger, J.D.; El-Genk, M.S.

1998-05-05

An apparatus and method for producing electricity from heat is disclosed. The present invention is a thermoelectric generator that uses materials with substantially no electrical resistance, often called superconductors, to efficiently convert heat into electrical energy without resistive losses. Preferably, an array of superconducting elements is encased within a second material with a high thermal conductivity. The second material is preferably a semiconductor. Alternatively, the superconducting material can be doped on a base semiconducting material, or the superconducting material and the semiconducting material can exist as alternating, interleaved layers of waferlike materials. A temperature gradient imposed across the boundary of the two materials establishes an electrical potential related to the magnitude of the temperature gradient. The superconducting material carries the resulting electrical current at zero resistivity, thereby eliminating resistive losses. The elimination of resistive losses significantly increases the conversion efficiency of the thermoelectric device. 4 figs.

Superconducting thermoelectric generator

DOEpatents

Metzger, J.D.; El-Genk, M.S.

1996-01-01

An apparatus and method for producing electricity from heat. The present invention is a thermoelectric generator that uses materials with substantially no electrical resistance, often called superconductors, to efficiently convert heat into electrical energy without resistive losses. Preferably, an array of superconducting elements is encased within a second material with a high thermal conductivity. The second material is preferably a semiconductor. Alternatively, the superconducting material can be doped on a base semiconducting material, or the superconducting material and the semiconducting material can exist as alternating, interleaved layers of waferlike materials. A temperature gradient imposed across the boundary of the two materials establishes an electrical potential related to the magnitude of the temperature gradient. The superconducting material carries the resulting electrical current at zero resistivity, thereby eliminating resistive losses. The elimination of resistive losses significantly increases the conversion efficiency of the thermoelectric device.

Superconducting thermoelectric generator

DOEpatents

Metzger, John D.; El-Genk, Mohamed S.

1998-01-01

An apparatus and method for producing electricity from heat. The present invention is a thermoelectric generator that uses materials with substantially no electrical resistance, often called superconductors, to efficiently convert heat into electrical energy without resistive losses. Preferably, an array of superconducting elements is encased within a second material with a high thermal conductivity. The second material is preferably a semiconductor. Alternatively, the superconducting material can be doped on a base semiconducting material, or the superconducting material and the semiconducting material can exist as alternating, interleaved layers of waferlike materials. A temperature gradient imposed across the boundary of the two materials establishes an electrical potential related to the magnitude of the temperature gradient. The superconducting material carries the resulting electrical current at zero resistivity, thereby eliminating resistive losses. The elimination of resistive losses significantly increases the conversion efficiency of the thermoelectric device.

Multi-component assembly casting

DOEpatents

James, Allister W.

2015-10-13

Multi-component vane segment and method for forming the same. Assembly includes: positioning a pre-formed airfoil component (12) and a preformed shroud heat resistant material (18) in a mold, wherein the airfoil component (12) and the shroud heat resistant material (18) each comprises an interlocking feature (24); preheating the mold; introducing molten structural material (46) into the mold; and solidifying the molten structural material such that it interlocks the pre-formed airfoil component (12) with respect to the preformed shroud heat resistant material (18) and is effective to provide structural support for the shroud heat resistant material (18). Surfaces between the airfoil component (12) and the structural material (46), between the airfoil component (12) and the shroud heat resistant material (18), and between the shroud heat resistant material (18) and the structural material (46) are free of metallurgical bonds.

Termination of Safeguards for Accountable Nuclear Materials at the Idaho National Laboratory

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

Michael Holzemer; Alan Carvo

2012-04-01

Termination of safeguards ends requirements of Nuclear Material Control and Accountability (MC&A) and thereby removes the safeguards basis for applying physical protection requirements for theft and diversion of nuclear material, providing termination requirements are met as described. Department of Energy (DOE) M 470.4 6 (Nuclear Material Control and Accountability [8/26/05]) stipulates: 1. Section A, Chapter I (1)( q) (1): Safeguards can be terminated on nuclear materials provided the following conditions are met: (a) 'If the material is special nuclear material (SNM) or protected as SNM, it must be attractiveness level E and have a measured value.' (b) 'The material hasmore » been determined by DOE line management to be of no programmatic value to DOE.' (c) 'The material is transferred to the control of a waste management organization where the material is accounted for and protected in accordance with waste management regulations. The material must not be collocated with other accountable nuclear materials.' Requirements for safeguards termination depend on the safeguards attractiveness levels of the material. For attractiveness level E, approval has been granted from the DOE Idaho Operations Office (DOE ID) to Battelle Energy Alliance, LLC (BEA) Safeguards and Security (S&S). In some cases, it may be necessary to dispose of nuclear materials of attractiveness level D or higher. Termination of safeguards for such materials must be approved by the Departmental Element (this is the DOE Headquarters Office of Nuclear Energy) after consultation with the Office of Security.« less

High Throughput Assay for Bacterial Adhesion on Acellular Dermal Matrices and Synthetic Surgical Materials

PubMed Central

Nyame, Theodore T.; Lemon, Katherine P.; Kolter, Roberto; Liao, Eric C.

2013-01-01

Background There has been increasing use of various synthetic and biologically derived materials in surgery. Biologic surgical materials are used in many plastic surgery procedures, ranging from breast reconstruction to hernia repairs. In particular, acellular dermal matrix (ADM) material has gained popularity in these applications. There is a paucity of data on how ADM compares to other surgical materials as a substrate for bacterial adhesion, the first step in formation biofilm, which occurs in prosthetic wound infections. We have designed a high throughput assay to evaluate Staphylococcus aureus adherence on various synthetic and biologically derived materials. Methods Clinical isolates of Staphylococcus aureus (strains SC-1 and UAMS-1) were cultured with different materials and bacterial adherence was measured using a resazurin cell vitality reporter microtiter assay. Four materials that are commonly utilized in reconstructive procedures were evaluated: prolene mesh, vicryl mesh, and two different ADM preparations (AlloDerm®, FlexHD®). We were able to develop a high throughput and reliable assay for quantifying bacterial adhesion on synthetic and biologically derived materials. Results The resazurin vitality assay can be reliably used to quantify bacterial adherence to acellular dermal matrix material, as well as synthetic material. S. aureus strains SC-1 and UAMS-1 both adhered better to ADM materials (AlloDerm® vs. FlexHD®) than to the synthetic material prolene. S. aureus also adhered better to vicryl than to prolene. Strain UAMS-1 adhered better to vicryl and ADM materials than did strain SC-1. Conclusion Our results suggest that S. aureus adheres more readily to ADM material than to synthetic material. We have developed an assay to rapidly test bacterial formation on surgical materials, using two S. aureus bacterial strains. This provides a standard method to evaluate existing and new materials with regard to bacterial adherence and potential propensity for infection. This assay is particularly important in the clinical context of the severe sequelae of post-operative infection. PMID:22030489

What LDEF means for development and testing of materials

NASA Technical Reports Server (NTRS)

Whitaker, Ann F.; Stuckey, Wayne K.; Stein, Bland A.

1993-01-01

The Long Duration Exposure Facility (LDEF) served as the ultimate laboratory to provide combined space environmental effects on materials. The LDEF structure and its 57 experiments contained an estimated 12,000 to 14,000 specimens of materials and materials processes. It not only provided information about the resistance of these materials to the space environment but gives us direction into future needs for spacecraft materials development and testing. This paper provides an overview of the materials effects observed on the satellite and suggests recommendations for the future work in space-qualified materials development and space environmental simulation.

Improved method and composition for immobilization of waste in cement-based material

DOEpatents

Tallent, O.K.; Dodson, K.E.; McDaniel, E.W.

1987-10-01

A composition and method for fixation or immobilization of aqueous hazardous waste material in cement-based materials (grout) is disclosed. The amount of drainable water in the cured grout is reduced by the addition of an ionic aluminum compound to either the waste material or the mixture of waste material and dry-solid cement- based material. This reduction in drainable water in the cured grout obviates the need for large, expensive amounts of gelling clays in grout materials and also results in improved consistency and properties of these cement-based waste disposal materials.

Electrochromic device

DOEpatents

Schwendemanm, Irina G [Wexford, PA; Polcyn, Adam D [Pittsburgh, PA; Finley, James J [Pittsburgh, PA; Boykin, Cheri M [Kingsport, TN; Knowles, Julianna M [Apollo, PA

2011-03-15

An electrochromic device includes a first substrate spaced from a second substrate. A first conductive member is formed over at least a portion of the first substrate. A first electrochromic material is formed over at least a portion of the first conductive member. The first electrochromic material includes an organic material. A second conductive member is formed over at least a portion of the second substrate. A second electrochromic material is formed over at least a portion of the second conductive member. The second electrochromic material includes an inorganic material. An ionic liquid is positioned between the first electrochromic material and the second electrochromic material.

Half-heusler alloys with enhanced figure of merit and methods of making

DOEpatents

Ren, Zhifeng; Yan, Xiao; Joshi, Giri; Chen, Shuo; Chen, Gang; Poudel, Bed; Caylor, James Christopher

2015-06-02

Thermoelectric materials and methods of making thermoelectric materials having a nanometer mean grain size less than 1 micron. The method includes combining and arc melting constituent elements of the thermoelectric material to form a liquid alloy of the thermoelectric material and casting the liquid alloy of the thermoelectric material to form a solid casting of the thermoelectric material. The method also includes ball milling the solid casting of the thermoelectric material into nanometer mean size particles and sintering the nanometer size particles to form the thermoelectric material having nanometer scale mean grain size.

Total materials consumption; an estimation methodology and example using lead; a materials flow analysis

USGS Publications Warehouse

Biviano, Marilyn B.; Wagner, Lorie A.; Sullivan, Daniel E.

1999-01-01

Materials consumption estimates, such as apparent consumption of raw materials, can be important indicators of sustainability. Apparent consumption of raw materials does not account for material contained in manufactured products that are imported or exported and may thus under- or over-estimate total consumption of materials in the domestic economy. This report demonstrates a methodology to measure the amount of materials contained in net imports (imports minus exports), using lead as an example. The analysis presents illustrations of differences between apparent and total consumption of lead and distributes these differences into individual lead-consuming sectors.

Nonterrestrial material processing and manufacturing of large space systems

NASA Technical Reports Server (NTRS)

Von Tiesenhausen, G.

1979-01-01

Nonterrestrial processing of materials and manufacturing of large space system components from preprocessed lunar materials at a manufacturing site in space is described. Lunar materials mined and preprocessed at the lunar resource complex will be flown to the space manufacturing facility (SMF), where together with supplementary terrestrial materials, they will be final processed and fabricated into space communication systems, solar cell blankets, radio frequency generators, and electrical equipment. Satellite Power System (SPS) material requirements and lunar material availability and utilization are detailed, and the SMF processing, refining, fabricating facilities, material flow and manpower requirements are described.

Laser detection of material thickness

DOEpatents

Early, James W.

2002-01-01

There is provided a method for measuring material thickness comprising: (a) contacting a surface of a material to be measured with a high intensity short duration laser pulse at a light wavelength which heats the area of contact with the material, thereby creating an acoustical pulse within the material: (b) timing the intervals between deflections in the contacted surface caused by the reverberation of acoustical pulses between the contacted surface and the opposite surface of the material: and (c) determining the thickness of the material by calculating the proportion of the thickness of the material to the measured time intervals between deflections of the contacted surface.

Methods of producing free-standing semiconductors using sacrificial buffer layers and recyclable substrates

DOEpatents

Ptak, Aaron Joseph; Lin, Yong; Norman, Andrew; Alberi, Kirstin

2015-05-26

A method of producing semiconductor materials and devices that incorporate the semiconductor materials are provided. In particular, a method is provided of producing a semiconductor material, such as a III-V semiconductor, on a spinel substrate using a sacrificial buffer layer, and devices such as photovoltaic cells that incorporate the semiconductor materials. The sacrificial buffer material and semiconductor materials may be deposited using lattice-matching epitaxy or coincident site lattice-matching epitaxy, resulting in a close degree of lattice matching between the substrate material and deposited material for a wide variety of material compositions. The sacrificial buffer layer may be dissolved using an epitaxial liftoff technique in order to separate the semiconductor device from the spinel substrate, and the spinel substrate may be reused in the subsequent fabrication of other semiconductor devices. The low-defect density semiconductor materials produced using this method result in the enhanced performance of the semiconductor devices that incorporate the semiconductor materials.

Inductively-Charged High-Temperature Superconductors And Methods Of Use

DOEpatents

Bromberg, Leslie

2003-09-16

The invention provides methods of charging superconducting materials and, in particular, methods of charging high-temperature superconducting materials. The methods generally involve cooling a superconducting material to a temperature below its critical temperature. Then, an external magnetic field is applied to charge the material at a nearly constant temperature. The external magnetic field first drives the superconducting material to a critical state and then penetrates into the material. When in the critical state, the superconducting material loses all the pinning ability and therefore is in the flux-flow regime. In some embodiments, a first magnetic field may be used to drive the superconducting material to the critical state and then a second magnetic field may be used to penetrate the superconducting material. When the external field or combination of external fields are removed, the magnetic field that has penetrated into the material remains trapped. The charged superconducting material may be used as solenoidal magnets, dipole magnets, or other higher order multipole magnets in many applications.

Universal Fragment Descriptors for Predicting Electronic and Mechanical Properties of Inorganic Crystals

NASA Astrophysics Data System (ADS)

Oses, Corey; Isayev, Olexandr; Toher, Cormac; Curtarolo, Stefano; Tropsha, Alexander

Historically, materials discovery is driven by a laborious trial-and-error process. The growth of materials databases and emerging informatics approaches finally offer the opportunity to transform this practice into data- and knowledge-driven rational design-accelerating discovery of novel materials exhibiting desired properties. By using data from the AFLOW repository for high-throughput, ab-initio calculations, we have generated Quantitative Materials Structure-Property Relationship (QMSPR) models to predict critical materials properties, including the metal/insulator classification, band gap energy, and bulk modulus. The prediction accuracy obtained with these QMSPR models approaches training data for virtually any stoichiometric inorganic crystalline material. We attribute the success and universality of these models to the construction of new materials descriptors-referred to as the universal Property-Labeled Material Fragments (PLMF). This representation affords straightforward model interpretation in terms of simple heuristic design rules that could guide rational materials design. This proof-of-concept study demonstrates the power of materials informatics to dramatically accelerate the search for new materials.

Fusion materials semiannual progress report for the period ending December 31, 1996

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

NONE

1997-04-01

This is the twenty-first in a series of semiannual technical progress reports on fusion materials. This report combines the full spectrum of research and development activities on both metallic and non-metallic materials with primary emphasis on the effects of the neutronic and chemical environment on the properties and performance of materials for in-vessel components. This effort forms one element of the materials program being conducted in support of the Fusion Energy Sciences Program of the US Department of Energy. The other major element of the program is concerned with the interactions between reactor materials and the plasma and is reportedmore » separately. The report covers the following topics: vanadium alloys; silicon carbide composite materials; ferritic/martensitic steels; copper alloys and high heat flux materials; austenitic stainless steels; insulating ceramics and optical materials; solid breeding materials; radiation effects, mechanistic studies and experimental methods; dosimetry, damage parameters, and activation calculations; materials engineering and design requirements; and irradiation facilities, test matrices, and experimental methods.« less

Automatically producing tailored web materials for public administration

NASA Astrophysics Data System (ADS)

Colineau, Nathalie; Paris, Cécile; Vander Linden, Keith

2013-06-01

Public administration organizations commonly produce citizen-focused, informational materials describing public programs and the conditions under which citizens or citizen groups are eligible for these programs. The organizations write these materials for generic audiences because of the excessive human resource costs that would be required to produce personalized materials for everyone. Unfortunately, generic materials tend to be longer and harder to understand than materials tailored for particular citizens. Our work explores the feasibility and effectiveness of automatically producing tailored materials. We have developed an adaptive hypermedia application system that automatically produces tailored informational materials and have evaluated it in a series of studies. The studies demonstrate that: (1) subjects prefer tailored materials over generic materials, even if the tailoring requires answering a set of demographic questions first; (2) tailored materials are more effective at supporting subjects in their task of learning about public programs; and (3) the time required to specify the demographic information on which the tailoring is based does not significantly slow down the subjects in their information seeking task.

Suitability of prostate cancer education materials: applying a standardized assessment tool to currently available materials.

PubMed

Weintraub, Debra; Maliski, Sally L; Fink, Arlene; Choe, Sarah; Litwin, Mark S

2004-11-01

Written educational materials serve as important teaching instruments for prostate cancer patients and their families. However, they must be understandable for their intended audiences. We examined prostate cancer brochures and pamphlets using the Suitability Assessment of Materials (SAM) instrument for the materials' overall suitability, readability, and cultural appropriateness. These factors are crucial to ensure that patients are able to understand and relate to the information. Our evaluation of 29 materials demonstrated that the majority, 22 (75.8%), scored "adequate" for their overall suitability. However, 26 materials (90%) scored "not suitable" for their reading grade level, while 55% of the materials could not be rated on cultural appropriateness because of lack of cues about the intended audience. Also, many of the materials scored poorly on content, graphics, self-efficacy, and learning motivation and stimulation. Most of the materials did well with typography and layout. Overall, the findings point to the need to carefully assess written materials used for multicultural audiences with low reading ability.

Recent developments in the field of environmental reference materials at the JRC Ispra.

PubMed

Muntau, H

2001-06-01

The production of reference materials for environmental analysis started in the Joint Research Centre at Ispra/Italy in 1972 with the objective of later certification by the BCR, but for obvious budget reasons only a fraction of the total production achieved at Ispra ever reached certification level, although all materials were produced according to the severe quality requirements requested for certified reference materials. Therefore, the materials not destinated to certification are in growing demand as inter-laboratory test materials and as laboratory reference materials, for internal quality control, e.g., by control charts. The history of reference material production within the Joint Research Centre is briefly reviewed and the latest additions described. New developments such as micro-scale reference materials intended for analytical methods requiring sample intakes at milligram or sub-milligram level and therefor not finding supply on the reference material market, and "wet" environmental reference materials, which meet more precisely the "real-world" environmental analysis conditions, are presented and the state-of-the-art discussed.

Thermal protection materials: Thermophysical property data

NASA Technical Reports Server (NTRS)

Williams, S. D.; Curry, Donald M.

1992-01-01

This publication presents a thermophysical property survey on materials that could potentially be used for future spacecraft thermal protection systems (TPS). This includes data that was reported in the 1960's as well as more current information reported through the 1980's. An attempt was made to cite the manufacturers as well as the data source in the bibliography. This volume represents an attempt to provide in a single source a complete set of thermophysical data on a large variety of materials used in spacecraft TPS analysis. The property data is divided into two categories: ablative and reusable. The ablative materials have been compiled into twelve categories that are descriptive of the material composition. An attempt was made to define the Arrhenius equation for each material although this data may not be available for some materials. In a similar manner, char data may not be available for some of the ablative materials. The reusable materials have been divided into three basic categories: thermal protection materials (such as insulators), adhesives, and structural materials.

Cladding material, tube including such cladding material and methods of forming the same

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

Garnier, John E.; Griffith, George W.

A multi-layered cladding material including a ceramic matrix composite and a metallic material, and a tube formed from the cladding material. The metallic material forms an inner liner of the tube and enables hermetic sealing of thereof. The metallic material at ends of the tube may be exposed and have an increased thickness enabling end cap welding. The metallic material may, optionally, be formed to infiltrate voids in the ceramic matrix composite, the ceramic matrix composite encapsulated by the metallic material. The ceramic matrix composite includes a fiber reinforcement and provides increased mechanical strength, stiffness, thermal shock resistance and highmore » temperature load capacity to the metallic material of the inner liner. The tube may be used as a containment vessel for nuclear fuel used in a nuclear power plant or other reactor. Methods for forming the tube comprising the ceramic matrix composite and the metallic material are also disclosed.« less

Collagen/hydroxyapatite composite materials with desired ceramic properties.

PubMed

Andronescu, Ecaterina; Voicu, Georgeta; Ficai, Maria; Mohora, Ioana Anita; Trusca, Roxana; Ficai, Anton

2011-01-01

Our purpose was to obtain and characterize some collagen/hydroxyapatite (COLL/HA) hybrid composite materials with desired ceramic properties. The ceramic properties of these materials were achieved by combining two drying methods: controlled air drying at 30°C followed by freeze-drying. Through the function of the air drying times, the materials morphology varies from porous materials (when the materials are freeze-dried) up to dense materials (when the materials are air-dried), while the combined drying allows us to obtain an intermediary morphology. The composite materials intended to be used as bone grafts and in a drug delivery system were characterized by XRD, FTIR, SEM, and also by determining the ceramic properties by using the Arthur method. The ceramic properties of these COLL/HA composite materials vary in large range, for instance the density of the materials varies from 0.06 up to 1.5 g/cm(3) while the porosity varies from 96.5% down to 27.5%.

Preparation and Characterization of Biomass-Derived Advanced Carbon Materials for Lithium-Ion Battery Applications

NASA Astrophysics Data System (ADS)

Hardiansyah, Andri; Chaldun, Elsy Rahimi; Nuryadin, Bebeh Wahid; Fikriyyah, Anti Khoerul; Subhan, Achmad; Ghozali, Muhammad; Purwasasmita, Bambang Sunendar

2018-04-01

In this study, carbon-based advanced materials for lithium-ion battery applications were prepared by using soybean waste-based biomass material, through a straightforward process of heat treatment followed by chemical modification processes. Various types of carbon-based advanced materials were developed. Physicochemical characteristics and electrochemical performance of the resultant materials were characterized systematically. Scanning electron microscopy observation revealed that the activated carbon and graphene exhibits wrinkles structures and porous morphology. Electrochemical impedance spectroscopy (EIS) revealed that both activated carbon and graphene-based material exhibited a good conductivity. For instance, the graphene-based material exhibited equivalent series resistance value of 25.9 Ω as measured by EIS. The graphene-based material also exhibited good reversibility and cyclic performance. Eventually, it would be anticipated that the utilization of soybean waste-based biomass material, which is conforming to the principles of green materials, could revolutionize the development of advanced material for high-performance energy storage applications, especially for lithium-ion batteries application.

Causes of shortage and delay in material supply: a preliminary study

NASA Astrophysics Data System (ADS)

Rahman, M. M.; Yap, Y. H.; Ramli, N. R.; Dullah, M. A.; Shamsuddin, M. S. W.

2017-11-01

Shortage and delay in materials supply is argued to be one of the most important factors that lead to delay in construction project delivery globally. However, the relevant underlying reasons vary from country to country. As such, this paper summarises the outcomes of a study that targeted identifying causes of shortage and delay in materials supply in Brunei Darussalam. The study was conducted through fifteen semi-structured interviews of contractors and materials suppliers in Brunei. The study identified six causes of shortageof materials and nine causes of delay in materials supply in Brunei. The most importantcausefor shortage of materials relates to the origin or availability of construction materials. On the other hand, the most influential cause of delay in material supply was found to be poor materials procurement and inventory management system, which has other underlying reasons such as late identification of the type of materials needed. The observations are expected to help in formulating or reviewing relevant policies, in order to ensure on-time project delivery.

Preparation and Characterization of Biomass-Derived Advanced Carbon Materials for Lithium-Ion Battery Applications

NASA Astrophysics Data System (ADS)

Hardiansyah, Andri; Chaldun, Elsy Rahimi; Nuryadin, Bebeh Wahid; Fikriyyah, Anti Khoerul; Subhan, Achmad; Ghozali, Muhammad; Purwasasmita, Bambang Sunendar

2018-07-01

In this study, carbon-based advanced materials for lithium-ion battery applications were prepared by using soybean waste-based biomass material, through a straightforward process of heat treatment followed by chemical modification processes. Various types of carbon-based advanced materials were developed. Physicochemical characteristics and electrochemical performance of the resultant materials were characterized systematically. Scanning electron microscopy observation revealed that the activated carbon and graphene exhibits wrinkles structures and porous morphology. Electrochemical impedance spectroscopy (EIS) revealed that both activated carbon and graphene-based material exhibited a good conductivity. For instance, the graphene-based material exhibited equivalent series resistance value of 25.9 Ω as measured by EIS. The graphene-based material also exhibited good reversibility and cyclic performance. Eventually, it would be anticipated that the utilization of soybean waste-based biomass material, which is conforming to the principles of green materials, could revolutionize the development of advanced material for high-performance energy storage applications, especially for lithium-ion batteries application.

Organic light emitting device architecture for reducing the number of organic materials

DOEpatents

D'Andrade, Brian [Westampton, NJ; Esler, James [Levittown, PA

2011-10-18

An organic light emitting device is provided. The device includes an anode and a cathode. A first emissive layer is disposed between the anode and the cathode. The first emissive layer includes a first non-emitting organic material, which is an organometallic material present in the first emissive layer in a concentration of at least 50 wt %. The first emissive layer also includes a first emitting organic material. A second emissive layer is disposed between the first emissive layer and the cathode, preferably, in direct contact with the first emissive layer. The second emissive material includes a second non-emitting organic material and a second emitting organic material. The first and second non-emitting materials, and the first and second emitting materials, are all different materials. A first non-emissive layer is disposed between the first emissive layer and the anode, and in direct contact with the first emissive layer. The first non- emissive layer comprises the first non-emissive organic material.

Materials discovery at high pressures

NASA Astrophysics Data System (ADS)

Zhang, Lijun; Wang, Yanchao; Lv, Jian; Ma, Yanming

2017-02-01

Pressure is a fundamental thermodynamic variable that can be used to control the properties of materials, because it reduces interatomic distances and profoundly modifies electronic orbitals and bonding patterns. It is thus a versatile tool for the creation of exotic materials not accessible at ambient conditions. Recently developed static and dynamic high-pressure experimental techniques have led to the synthesis of many functional materials with excellent performance: for example, superconductors, superhard materials and high-energy-density materials. Some of these advances have been aided and accelerated by first-principles crystal-structure searching simulations. In this Review, we discuss recent progress in high-pressure materials discovery, placing particular emphasis on the record high-temperature superconductivity in hydrogen sulfide and on nanotwinned cubic boron nitride and diamond, the hardest known materials. Energy materials and exotic chemical materials obtained under high pressures are also discussed. The main drawback of high-pressure materials is their destabilization after pressure release; this problem and its possible solutions are surveyed in the conclusions, which also provide an outlook on the future developments in the field.

Study of materials performance model for aircraft interiors

NASA Technical Reports Server (NTRS)

Leary, K.; Skratt, J.

1980-01-01

A demonstration version of an aircraft interior materials computer data library was developed and contains information on selected materials applicable to aircraft seats and wall panels, including materials for the following: panel face sheets, bond plies, honeycomb, foam, decorative film systems, seat cushions, adhesives, cushion reinforcements, fire blocking layers, slipcovers, decorative fabrics and thermoplastic parts. The information obtained for each material pertains to the material's performance in a fire scenario, selected material properties and several measures of processability.

Effect of Material Ion Exchanges on the Mechanical Stiffness Properties and Shear Deformation of Hydrated Cement Material Chemistry Structure C-S-H Jennit - A Computational Modeling Study

DTIC Science & Technology

2014-01-01

Study Material properties and performance are governed by material molecular chemistry structures and molecular level interactions. Methods to...understand relationships between the material properties and performance and their correlation to the molecular level chemistry and morphology, and thus...find ways of manipulating and adjusting matters at the atomistic level in order to improve material performance are required. A computational material

Materials Requirements for Advanced Energy Systems - New Fuels. Volume 3: Materials Research Needs in Advanced Energy Systems Using New Fuels

DTIC Science & Technology

1974-07-01

elec- Materials se: trode materials and associ- operational ated conductors. 2.5.1 General. H" (02) Materials resources Technoeconomic analysis - None...Advanced Energy Systems Using New Fnels VIII Correlation and Analysis of Materials Requirements IX Research Recommendations and Priorities The authois...of government and industrial organizal ions who gave us the benefit of their knowledge and experience. iv VIII CORRELATION ANU ANALYSIS OF MATERIALS

Design of adaptive load mitigating materials usingnonlinear stress wave tailoring

DTIC Science & Technology

2016-02-24

for granular material use). 3 • Prof. Trudy Kriven (UIUC, Materials Science) is an expert in ceramic and geopolymer fabrication. • Prof. John...Figure A5.1: Schematic diagram showing the 1D chain of spherical elements in contact with (a) a uniform linear medium and (b) a composite linear...each material point to consisting of one of the given material constituents, we allow each material point to be assigned a composite material that is

The geomechanical strength of carbonate rock in Kinta valley, Ipoh, Perak Malaysia

NASA Astrophysics Data System (ADS)

Mazlan, Nur Amanina; Lai, Goh Thian; Razib, Ainul Mardhiyah Mohd; Rafek, Abdul Ghani; Serasa, Ailie Sofyiana; Simon, Norbert; Surip, Noraini; Ern, Lee Khai; Mohamed, Tuan Rusli

2018-04-01

The stability of both cut rocks and underground openings were influenced by the geomechanical strength of rock materials, while the strength characteristics are influenced by both material characteristics and the condition of weathering. This paper present a systematic approach to quantify the rock material strength characteristics for material failure and material & discontinuities failure by using uniaxial compressive strength, point load strength index and Brazilian tensile strength for carbonate rocks. Statistical analysis of the results at 95 percent confidence level showed that the mean value of compressive strength, point load strength index and Brazilian tensile strength for with material failure and material & discontinuities failure were 76.8 ± 4.5 and 41.2 ± 4.1 MPa with standard deviation of 15.2 and 6.5 MPa, respectively. The point load strength index for material failure and material & discontinuities failure were 3.1 ± 0.2 MPa and 1.8 ± 0.3 MPa with standard deviation of 0.9 and 0.6 MPa, respectively. The Brazilian tensile strength with material failure and material & discontinuities failure were 7.1 ± 0.3 MPa and 4.1 ± 0.3 MPa with standard deviation of 1.4 and 0.6 MPa, respectively. The results of this research revealed that the geomechanical strengths of rock material of carbonate rocks for material & discontinuities failure deteriorates approximately ½ from material failure.

78 FR 42998 - Hazardous Materials: Improving the Safety of Railroad Transportation of Hazardous Materials

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-18

... Materials: Improving the Safety of Railroad Transportation of Hazardous Materials AGENCY: Pipeline and... that affect the safety of the transportation of hazardous materials by rail and are seeking input from... authority to FRA. 49 CFR 1.89(a) through (q). The Federal hazardous materials transportation laws, 49 U.S.C...

Coated electroactive materials

DOEpatents

Amine, Khalil; Abouimrane, Ali

2016-08-30

A process includes suspending an electroactive material in a solvent, suspending or dissolving a carbon precursor in the solvent; and depositing the carbon precursor on the electroactive material to form a carbon-coated electroactive material. Compositions include a graphene-coated electroactive material prepared from a solution phase mixture or suspension of an electroactive material and graphene, graphene oxide, or a mixture thereof.

Meeting EFL Learners Halfway by Using Locally Relevant Authentic Materials

ERIC Educational Resources Information Center

Thomas, Catherine

2014-01-01

The author defines and describes authentic materials and discusses their benefits--citing the Input Hypothesis and the Output Principle in support of such materials--as well as some challenges of using authentic materials. Five categories of authentic materials are presented, and sources for materials and ways to use them in the EFL classroom are…

Nanocrystalline ceramic materials

DOEpatents

Siegel, R.W.; Nieman, G.W.; Weertman, J.R.

1994-06-14

A method is disclosed for preparing a treated nanocrystalline metallic material. The method of preparation includes providing a starting nanocrystalline metallic material with a grain size less than about 35 nm, compacting the starting nanocrystalline metallic material in an inert atmosphere and annealing the compacted metallic material at a temperature less than about one-half the melting point of the metallic material. 19 figs.

Near-Resonant Thermomechanics of Energetic and Mock Energetic Composite Materials

DTIC Science & Technology

2016-11-01

munition design . 15. SUBJECT TERMS Energetic Materials; Explosives; Mechanical Vibration; Thermomechanics; Damping; Plasticity 16. SECURITY...preliminary computational modeling tools, which can be used to predict material response during energetic material formulation and munition design . Key...which can be used to predict material response during energetic material formulation and munition design . More specifically, Task Order 0001

The Art Recipe Book, Volume One: 60 Non-toxic Art Materials from Readily Available Materials.

ERIC Educational Resources Information Center

Janeczko, Donna

This collection of recipes is intended for art teachers to provide low-cost, non-toxic materials for classroom use. The materials needed are readily available and can be purchased in quantity to help the budget conscious teacher. Recipes included are for modeling materials, edible modeling materials, paints and inks, adhesives, fixatives, and…

Full-scale aircraft cabin flammability tests of improved fire-resistant materials, test series 2

NASA Technical Reports Server (NTRS)

Stuckey, R. N.; Bricker, R. W.; Kuminecz, J. F.; Supkis, D. E.

1976-01-01

Full-scale aircraft flammability tests in which the effectiveness of new fire-resistant materials was evaluated by comparing their burning characteristics with those of other fire-resistant aircraft materials were described. New-fire-resistant materials that are more economical and better suited for aircraft use than the previously tested fire-resistant materials were tested. The fuel ignition source for one test was JP-4; a smokeless fuel was used for the other test. Test objectives, methods, materials, and results are presented and discussed. The results indicate that, similar to the fire-resistant materials tested previously, the new materials decompose rather than ignite and do not support fire propagation. Furthermore, the new materials did not produce a flash fire.